Eventos - Artigos: Recent submissions

  • IPEN-DOC 27457

    BASSO, LUANA S.; GATTI, LUCIANA V. ; MARANI, LUCIANO; DOMINGUES, LUCAS G. ; CRISPIM, STEPHANE P.; NEVES, RAIANE A.L.. Determinação das concentrações de CH4 na Amazônia Brasileira utilizando perfis verticais de avião. In: ENCONTRO ACADÊMICO DA ENGENHARIA AMBIENTAL DA EEL-USP, 3., 3-4 de junho, 2019, Lorena, SP. Anais... Lorena, SP: Escola de Engenharia de Lorena - USP, 2019.

    Palavras-Chave: methane; climatic change; greenhouse gases; ecological concentration; amazon river

    Como referenciar este item
    Icon

  • IPEN-DOC 27456

    SANTIAGO, A.G.; CAMPOS, C.S.; MACEDO, M.M.G.; DAGUANO, J.K.M.B.; DERNOWSEK, J.A. ; RODAS, A.C.D.. Exploring different Convolutional Neural Networks architectures to identify cells in spheroids. In: BRAZILIAN CONGRESS IN BIOMEDICAL ENGINEERING, 27th, October 26-30, 2020, Vitória, ES. Proceedings... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2020. p. 2256-2260.

    Abstract: The cultivation of cells in 3D has gained more interest in research once 3D architecture can be closer to full cell physiological functionality. The cultivation of the cells in a spheroid format has shown very promising results, further for bioprinting developing so fast during the last decade. The interaction of spheroids and the matrix, or bioink, have proportionate new structures to be analyzed, specially if one would like to follow the whole system (spheroid and bioink) without fluorescent dyes. Trying to solve this image limitation, the aim of this paper is to present a study on different Convolutional Neural Networks (CNN) architectures employed to identify different structures in fibroblast NIH-3T3 spheroids. Three different architectures were considered: GoogleNet, ResNet18 and AlexNet, all implemented in Python 3.7 using the PyTorch Application Interface Programming (API). Given a spheroid image taken in a light microscope, four structures can be identified: the cell, the dead cell, the impurity/contamination and the background consisting of a gel in which the spheroid is immersed. All four CNN architectures were trained and evaluated with a dataset consisting of over 370 samples, split into a training set (≈ 70%), a test set (≈ 20%) and a validation set (≈ 10%). Since our dataset has unbalanced classes, a data augmentation was applied in order to provide a comparable number of samples for all classes being considered.

    Palavras-Chave: animal cells; spheroids; neural networks; cell cultures; fibroblasts; image processing

    Como referenciar este item
    Icon

  • IPEN-DOC 27455

    PIERETTI, EURICO F. ; NEVES, MAURICIO D.M. das ; ANTUNES, RENATO A.. Corrosion analysis of a marked biomaterial. In: BRAZILIAN CONGRESS IN BIOMEDICAL ENGINEERING, 27th, October 26-30, 2020, Vitória, ES. Proceedings... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2020. p. 1968-1973.

    Abstract: Marking is one of the last steps of manufacturing an implantable biomaterial. The marks on its surface constitute a permanent set of information in order to provide identification and traceability of the biomedical device. These markings become stress concentrators and regions with probability for the occurrence of failures that can lead to fracture; besides damaging the passive layer, naturally formed on stainless steels surfaces, favoring the beginning of several forms of degradation. This work presents the effect of two metal implant marking techniques on the corrosion resistance of ISO 5832-1 austenitic stainless steel, one of the most used surgical biomaterials used in Brazil. Engraving was carried out with mechanical and laser beam marking techniques were prepared. The electrochemical behavior was characterized by cyclic potentiodynamic polarization curves and indicate that the laser marking technique is the one that most affects the passive layer of the material when compared to the mechanical engraving.

    Palavras-Chave: medical supplies; corrosion; chemical reactions; lasers; reliability; prostheses

    Como referenciar este item
    Icon

  • IPEN-DOC 27454

    NAMBA, A.F.; DEL-VALLE, M. ; DAGHASTANLI, N.A.; ANA, P.A.. In vitro study of the microstructural effects of photodynamic therapy in medical supplies when used for disinfection. In: BRAZILIAN CONGRESS IN BIOMEDICAL ENGINEERING, 27th, October 26-30, 2020, Vitória, ES. Proceedings... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2020. p. 1705-1710.

    Abstract: Cleaning and disinfecting surfaces and materials in health services are primary elements in infection control measures. For thermosensitive materials, the chemical agents used have disadvantages such as the odor of the products, which can cause allergic reactions to patients and the nursing staff. Photodynamic therapy (PDT) has been shown to be an effective technique in the treatment of infections caused by different microorganisms; however, nothing is known about the effects of this technique on the microstructure of hospital supplies. This in vitro study aimed to evaluate the effects of 0.2% peracetic acid, 1% sodium hypochlorite and PDT with 0.01% methylene blue on the composition and color changes of hospital masks and extensions. For this purpose, 100 mask samples and 100 extension samples were randomly distributed in 20 experimental groups (n = 10, 10 groups for each material), in which the applied substance was varied (sodium hypochlorite, peracetic acid and PDT) and the number of applications (without application, 1, 2 or 3 applications). The compositional analysis was performed by Fourier transform infrared spectroscopy, while the color changes were evaluated using image analysis by CIElab method evaluating the parameters L*, a*, b* and ∆E. The statistical analysis was performed at 5% significance level. It was observed that all agents altered the composition of the materials in a similar way. Although all agents promoted changes in different parameters evaluated, peracetic acid and methylene blue alone altered the final color perceived only in extensions. It was concluded that 0.2% peracetic acid, 1% sodium hypochlorite and PDT alter the chemical composition of both masks and extensions, and that such changes have a positive relationship with the number of treatments performed. These compositional changes may be related to the color changes promoted in both materials by all agents tested.

    Palavras-Chave: photodynamic therapy; sterilization; medical supplies; lasers

    Como referenciar este item
    Icon

  • IPEN-DOC 27453

    FORJAZ, C.R.H.; ZEZELL, D.M. ; ANA, P.A.. Temperature generation and transmission in root dentin during Nd:YAG laser irradiation for preventive purposes. In: BRAZILIAN CONGRESS IN BIOMEDICAL ENGINEERING, 27th, October 26-30, 2020, Vitória, ES. Proceedings... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2020. p. 1031-1035.

    Abstract: High-intensity lasers are widely used in dental procedures and the heating produced on the surface is necessary to ensure protective activity against the development of caries and erosion lesions. However, caution should be exercised regarding the spread of heat to the pulp, periodontal tissue and alveolar bone, which can cause harm to these tissues. This study sought to evaluate the generation and transmission of heat in the root dentin and adjacent tissues during irradiation with Nd:YAG laser for preventive activity. For that, 15 lower incisor human teeth had an area of 9 mm2 of root dentin irradiated with Nd:YAG laser (λ=1.064 μm, 10 Hz, 60 mJ/pulse, 84.9 J/cm2) for 30s. During irradiations, pulpal temperature was evaluated by fast-response thermocouples, while surface temperature and heat distribution on surrounding tissues were measured by infrared thermography. It was observed a mean surface temperature increase of 293.48±30.6° C in root dentin surface, and 15.85 ± 39.6° C below the irradiated area, 11.72 ± 8.7° C above the irradiated area, 19.77 ± 4.9° C at 1 cm laterally and 7.03 ± 2.7° C at 2 cm laterally to the irradiated area. The mean pulpal temperature augment registered was 6.5±1.4° C. It can be concluded that Nd:YAG laser irradiation promoted surface temperature rises that suggest chemical changes on dentin; however, the temperature increases generated in the adjacent tissues (region of periodontal ligament) and in the pulp chamber may be dangerous in future clinical application considering the irradiation time of 30 s made in this study. Therefore, this laser protocol can be used as long as the irradiation time is reduced in future studies.

    Palavras-Chave: dentistry; dentin; neodymium lasers; yttrium compounds; teeth; caries

    Como referenciar este item
    Icon

  • IPEN-DOC 27452

    CARVALHO, C.M.S.; MARINELI, A.G.F.; SANTOS, L. dos; FREITAS, A.Z. de ; AMARAL, M.M.. Evaluation of the Heart Rate Variability with Laser Speckle Imaging. In: BRAZILIAN CONGRESS IN BIOMEDICAL ENGINEERING, 27th, October 26-30, 2020, Vitória, ES. Proceedings... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2020. p. 430-433.

    Abstract: The Autonomic Nervous System (ANS) is responsible for regulating various physiological processes in the human body. The Heart Rate Variability (HRV) represents a measurement used in evaluating the modulation of the ANS in different physiological conditions such as stress, physical activity, sleep, metabolic alterations, and, also, pathological conditions. Physical activity results in important changes in the cardiovascular system, such as an increase in blood flow and a decrease of the peripheral vascular resistance. Monitoring the peripheral microcirculation represents an important aid in evaluating the general conditions of an individual. The Laser Speckle Contrast Analysis (LASCA) is a non-invasive optical resource developed that uses nonionizing radiation in the region of the infrared and is important in the diagnosis of problems regarding the peripheral microcirculation. This work aimed to implement a method to obtain the HRV through the peripheral microcirculation utilizing the Laser Speckle Contrast Analysis (LASCA) technique. A commercial LASCA equipment was used to obtain a face-video. A custom software was implemented to process the LASCA videos and obtain the HRV. A heart rate monitor (HRM) was also utilized to measure the HRV and the values were compared against the ones obtained with LASCA. The method had consistent results in obtaining both the pulsation and the HRV, making it possible for future studies to use such a technique.

    Palavras-Chave: lasers; images; cardiovascular system; heart; blood circulation; image processing

    Como referenciar este item
    Icon

  • IPEN-DOC 27348

    LEMOS, F.L. ; BIANCHI, P.H. . A systemic approach to information and cyber security. In: INTERNATIONAL CONFERENCE ON NUCLEAR SECURITY, February 10-14, 2020, Vienna, Austria. Proceedings... 2020. p. 1-6.

    Abstract: Design Based Threat, or DBT, is a common principle for physical and cyber protection, which is based on threat assessments. The protection, cyber or physical, will be planned based on the type of the identified threat. While we acknowledge the importance of the DBT, we argue that following this line of reasoning may limit our ability to grasp other vulnerabilities the system may have due to the following assumptions: a) The system will behave according to the way we think it should, based on a predetermined fashion. b) If each component of the system is reliable, then the system will be reliable. Systems theory assumes that accidents are a result of systemic factors, and does not have a single root-cause, generally a failure, that starts a chain of events leading to the accident. Moreover, systems theory assumes that security and safety are emergent properties of a system that result from the interactions between the components of that system. Therefore, accidents are a problem of control of the interactions between the components of the system rather than a problem of failures of components. In the systemic approach a cyber security system is treated as part of the whole socio-technical complex system, where humans are components of the system and interact with the computerized controls. The organizational culture permeates the entire system affecting decisions and, consequently, the interactions between the components. Weak safety and security cultures will eventually contribute for the system to migrate to hazardous states leading to losses or accidents. The paper analyzes the roles of organizational, safety and security cultures, as underlying factors that can lead to the deterioration of the hierarchical control structure, which is supposed to keep the interactions between the components of the system within desirable constraints.

    Palavras-Chave: cybernetics; security; risk assessment; information systems; organizational models; management

    Como referenciar este item
    Icon

  • IPEN-DOC 27339

    TESSARO, ANA P.G. ; ROLINDO, NATALIE C. ; MARUMO, JULIO T. ; VICENTE, ROBERTO ; LAS CASAS, ALEXANDRE . Use of ionizing radiation for treatment and extraction of organic compounds from petroleum sludge. In: ANNUAL WASTE MANAGEMENT CONFERENCE, 45th, March 3-7, 2019, Phoenix, Arizona, USA. Proceedings... Tempe, Arizona, USA: Waste Management Symposia, 2019. p. 1-7.

    Abstract: This paper presents preliminary results of a technical feasibility study of the use of an electron beam accelerator for the treatment of petroleum sludge and the degradation of organic and inorganic compounds. After analyzing the results of previous studies, the doses of the pilot study were defined.

    Palavras-Chave: chemical radiation effects; electron beams; feasibility studies; inorganic compounds; ionizing radiations; organic compounds; petroleum; radiation doses; sludges

    Como referenciar este item
    Icon

  • IPEN-DOC 27338

    ROLINDO, NATALIE C. ; TESSARO, ANA P.G. ; SMITH, RICARDO B. ; CAMPOS, CESAR ; SAID, YASSER ; MARUMO, JULIO T. ; VICENTE, ROBERTO . Inventory and characterization of categories 3-5 disused sealed radioactive sources. In: ANNUAL WASTE MANAGEMENT CONFERENCE, 45th, March 3-7, 2019, Phoenix, Arizona, USA. Proceedings... Tempe, Arizona, USA: Waste Management Symposia, 2019. p. 1-10.

    Abstract: Brazil has one of the biggest inventories of SRS in the world, not only because of the large industrial park, the well-developed health care infrastructure and the numerous mining operations, but also by the use of radioactive sources in consumer products, such as smoke detectors, lightning arresters, surge protectors and even cardiac pacemakers. Presently, the inventory of DSRS at the WML is of more than 10,000; if the sources from lightning arresters, smoke detectors and Ir-192 with activities above the clearance levels are included, the estimate is over 150,000. The Waste Management Laboratory (WML) of the Nuclear and Energy Research Institute (IPEN/CNEN-SP) is responsible for the management and treatment of these sources. An important aspect to consider is that Brazil does not have a defined strategy or a protocol for screening and inventorying these sources, whose management was limited only to storage. The WML started the development of methods and operational work, to characterize and reduce the total volume of this inventory for the borehole-type final disposal facility yet to be constructed, where the DSRS will be disposed of. The information available from these sources is in a database created in 1980, when the sources began to be received. Several records on the FRSD that were checked are incomplete or simply incorrect, since there is no correspondence between the dates of entry of these sources in the storage and their physical characteristics. Some reasons can be listed to try to understand the divergences: the inspection when receiving the sources was not possible, no inspection procedure was defined, there were technical difficulties to open the packages. The objective of this work is to organize the inventory in a standardized way, control access, traceability, reduction of the necessary time to locate and characterize the sources upon reception, and of the repetitive work in the operational routine, and finally release of space in the storage.

    Palavras-Chave: boreholes; inspection; iridium 192; lightning arresters; radiation sources; radioactive waste storage; smoke detectors

    Como referenciar este item
    Icon

  • IPEN-DOC 27337

    SMITH, RICARDO B. ; TESSARO, ANA P.G. ; ROLINDO, NATALIE C. ; VICENTE, ROBERTO . Further analyses of the unburied Goiania Accident packages. In: ANNUAL WASTE MANAGEMENT CONFERENCE, 45th, March 3-7, 2019, Phoenix, Arizona, USA. Proceedings... Tempe, Arizona, USA: Waste Management Symposia, 2019. p. 1-7.

    Abstract: In 1987, in the city of Goiania, Brazil, a derelict teletherapy machine was disassembled by scavengers and Cs-137 was released in the environment, unleashing the biggest radiological accident in Brazil. During the 15 days before the accident was acknowledged, some contaminated materials were sold and delivered to recycling factories in a few cities in the state of Sao Paulo, Brazil, in the form of metal scrap and recycled paper bales. The contaminated material was then collected, the metal scrap was conditioned in forty-three 200-liter drums, and the paper bales were stored in fifty 1.6 cubic meter steel boxes at the interim storage of the Nuclear and Energy Research Institute (IPEN), in the city of Sao Paulo, and there remained ever since. In 2017, 30 years later, initial analyses were performed at a sample of these boxes, checking for their activity, weight, and incongruences between the original values recorded at the time of collection and the measurement results 30 years later. The results indicated that none of the boxes checked were close to the clearance limit and that, without any sort of treatment, this radioactive waste should be stored for at least 150 years more. Visual inspection could not be performed at that time. Nowadays, some of the boxes were opened and samples from the contaminated material inside were taken for analysis. The main objective of this work is to report the results from the evaluation of the physical state of this material. After these analyses, the treatment options for volume reduction that were previously proposed were reviewed, and the method that best suits the current characteristics of the waste was chosen.

    Palavras-Chave: cesium 137; environment; radiation accidents; radiation hazards; radiation protection; radioactive waste storage; radioactive wastes; radiotherapy; recycling; scrap metals; steels; urban areas

    Como referenciar este item
    Icon

  • IPEN-DOC 27336

    SILVA, SIDNEY L. da; PRADO, FELIPE M.; TOFFOLI, DANIEL J.; WETTER, NIKLAUS U. . Measuring photoelastic dispersion coefficients in material samples with digital holography. In: BJELKHAGEN, HANS I. (Ed.) SPIE PHOTONICS WEST; SPIE OPTO, February 1-6, 2020, San Francisco, USA. Proceedings... Washington, USA: SPIE, 2020. p. 113060P-1 - 113060P-7. (Proceedings SPIE 11306, Practical Holography XXXIV: Displays, Materials, and Applications). DOI: 10.1117/12.2544874

    Abstract: Polarized Digital Holography (PHD) is a fast and efficient tool for analyzing mechanical effects in materials. Especially when the task requires non-invasive techniques that do not damage the material in study, the use of PHD has great perspectives. The most common methods of digital reconstruction use the convolution theory to discretize the Huygens- Fresnel integral. When external stresses are applied to photoelastic materials, the relationship between these stresses and phase differences observed by polarization holography is an intrinsic characteristic of the material called the photoelastic dispersion coefficient. In photoelasticity, this coefficient depends on the wavelength. By using PHD the authors show in the present paper that the photoelastic dispersion coefficient also depends on the wavelength in Holography. A Mach- Zehnder interferometer, modified with the inclusion of linear polarizers, was built to verify this effect in a sample of photoelastic material. In this set-up, two coherent light sources with different wavelengths were used. For the analysis, a digital method was created that correlated the mean stresses differences on the photoelastic material sample and the mean phases differences at each distinct wavelength.

    Palavras-Chave: interferometry; holography; stresses; polarization; photoelasticity

    Como referenciar este item
    Icon

  • IPEN-DOC 27335

    FREITAS, ANDERSON Z. de ; RIBEIRO, LUCAS A. de S. ; NEGRINI NETO, OSVALDO ; SARKIS, JORGE E.S. ; SIQUEIRA, ANDRESSA N. . Optical-coherence-tomography-based algorithm for handwriting forensic analysis. In: JALALI, BAHRAM (Ed.); KITAYAMA, KEN-ICHI (Ed.) SPIE PHOTONICS WEST; SPIE OPTO, February 1-6, 2020, San Francisco, USA. Proceedings... Washington, USA: SPIE, 2020. p. 112990P-1 - 112990P-8. (Proceedings SPIE 11299, AI and Optical Data Sciences). DOI: 10.1117/12.2543356

    Abstract: This work describes a new method for handwriting forensic analysis using optical coherence tomography (OCT) images. The region of interest (ROI) in documents signature to be analyzed were pre-selected with a traditional optical analyzer (Docucenter 2000 – Projectina®) equipped with different wavelengths light sources and bandpass filters coupled detector. The ROI where then submitted to OCT to 3D imaging (OCP930SR, Thorlabs Inc.) with optical resolution of 6.0 microns. One original and 5 falsified signatures were produced by 5 different individuals, using a block of 5 sheets of white sulfite paper A4 size and weight of 75 g/m^2, using the same blue ballpoint pen and in the same surface. For pressure pen calibration, were developed a system computer controlled to maintain the pressure constant during writing linear traces, 15 different pressure configuration were applied to each linear trace, resulting in a relation between deformation and applied pressure. An autonomous algorithm was developed to make surface detection, across OCT tomographic images, correct the paper surface curvature, detect and measure deformation on paper due to pen pressure, generating a new image in false color from differential pressure, based in previous calibration. This new image can be considered as a “fingerprint pressure” signature. This methodology may assist the forensic expert in correctly determining the authorship of a signature.

    Palavras-Chave: coherent radiation; tomography; crime detection; nuclear forensics; pressure measurement; hands

    Como referenciar este item
    Icon

  • IPEN-DOC 27334

    DIPOLD, JESSICA ; SILVA, DANILO A.A. da ; BERECZKI, ALLAN ; JIMENEZ-VILLAR, E. ; WETTER, NIKLAUS U. . Polydispersed Nd3+:YVO4+SiO2 powders for highly efficient random lasers. In: JIANG, SHIBIN (Ed.); DIGONNET, MICHEL J.F. (Ed.) SPIE PHOTONICS WEST; SPIE OPTO, February 1-6, 2020, San Francisco, USA. Proceedings... Washington, USA: SPIE, 2020. p. 112760N-1 - 112760N-8. (Proceedings SPIE 11276, Optical Components andMaterials XVII). DOI: 10.1117/12.2545028

    Abstract: Random lasers are cheap and easy to fabricate, having several different applications such as early cancer detection, encryption and Speckle-free imaging. However, few fabricated random lasers present high efficiency, which limits their possible applications. In a recent work, our group achieved a record efficiency by developing random lasers that use compacted, polydispersed yttrium vanadate doped with neodymium (Nd3+:YVO4 ) powders to create separate regions for gain and light diffusion. Large particles are responsible for the light diffusion, while the small particles that occupy the spaces between them create gain pockets, absorbing the pumped light. In this work, this strategy is refined by using passive particles (SiO2) for light diffusion, restricting the laser active particles to the gain pockets. The first attempt with this strategy used 30% of Nd3+:YVO4 small powders and 70% of large SiO2 particles. Without any further optimization, the result achieved is already 40% of the highest obtained efficiency in the previously studied Nd3+:YVO4 polydisperse sample, showing a promising result to further improve this new strategy and reach even larger efficiencies with less laser active material.

    Palavras-Chave: randomness; lasers; optical pumping; gain; absorption

    Como referenciar este item
    Icon

  • IPEN-DOC 27333

    WETTER, NIKLAUS U. ; SILVA, DIEGO S. da ; KASSAB, LUCIANA R.P.; ROSSI, WAGNER de . Double line Neodymium doped GeO2-PbO waveguide amplifier for the second telecom window. In: JIANG, SHIBIN (Ed.); DIGONNET, MICHEL J.F. (Ed.) SPIE PHOTONICS WEST; SPIE OPTO, February 1-6, 2020, San Francisco, USA. Proceedings... Washington, USA: SPIE, 2020. p. 112760M-1 - 112760M-7. (Proceedings SPIE 11276, Optical Components and Materials XVII). DOI: 10.1117/12.2544291

    Abstract: We report the production of active double waveguides in germanate glasses, GeO2-PbO doped with Nd3+, by direct femtosecond laser writing. The glasses were produced using the melt-quenching technique and the active waveguides were written using 30 fs laser pulses at 800 nm with different parameters of writing speeds and pulse energies depending on the rare earth elements used for doping. The photo-induced refractive index change was 5.2x10-3. The Nd doped sample exhibited a relative gain of 3.6 dB/cm for 1.6 mW of 805 nm pump power. The results obtained in present work demonstrate that Nd3+ doped GeO2-PbO glasses are promising materials for the fabrication of integrated amplifiers, lossless components and lasers based on germanate glasses.

    Palavras-Chave: optical systems; spectroscopy; amorphous state; doped materials; metallic glasses; neodymium; germanium oxides; lead oxides

    Como referenciar este item
    Icon

  • IPEN-DOC 27332

    BERECZKI, A. ; PAES, JOAO P.F. ; WETTER, NIKLAUS U. . Three-level Nd:YLF Raman laser directly pumped by a beam shaped diode bar. In: KUDRYASHOV, ALEXIS V. (Ed.); PAXTON, ALAN H. (Ed.); ILCHENKO, VLADIMIR S. (Ed.); ARMANI, ANDREA M. (Ed.) SPIE PHOTONICS WEST; SPIE LASE, February 1-6, 2020, San Francisco, USA. Proceedings... Washington, USA: SPIE, 2020. p. 1126614-1 - 1126614-8. (Proceedings SPIE 11266, Laser Resonators, Microresonators, and Beam Control XXII). DOI: 10.1117/12.2544844

    Abstract: Low heat generation can be obtained when pumping Nd:YLF at wavelengths of 872 nm and 880 nm and emitting at the three-level transition of 908 nm. These transitions show very low quantum defect with efficiencies of 0.96 and 0.97, respectively. However, the low average absorption cross-section at these wavelengths makes efficient absorption even for longitudinal pump setups difficult. Using a beam-shaped pump diode instead of a fiber-coupled diode bar may be an effective means of increasing absorption because it can provide for π-polarized radiation which shows higher absorption cross section. In this work, a Nd:YLF was pumped at 872 nm by a diode bar using beam-shaping. Results were compared to pumping at 872 and 880 nm with non-polarized fiber-coupled diodes. Stimulated Raman scattering was also obtained with a KGW crystal generating first Stokes emissions at 990 nm and 976 nm.

    Palavras-Chave: laser radiation; raman spectra; neodymium lasers; yttrium; lithium; beam shaping; energy levels

    Como referenciar este item
    Icon

  • IPEN-DOC 27331

    BERECZKI, A. ; WETTER, NIKLAUS U. . Dynamically stable lasers from commercial Nd:YAG modules with high beam quality and single-frequency: the correct choice of the fundamental waist size at the rod. In: KUDRYASHOV, ALEXIS V. (Ed.); PAXTON, ALAN H. (Ed.); ILCHENKO, VLADIMIR S. (Ed.); ARMANI, ANDREA M. (Ed.) SPIE PHOTONICS WEST; SPIE LASE, February 1-6, 2020, San Francisco, USA. Proceedings... Washington, USA: SPIE, 2020. p. 1126617-1 - 1126617-10. (Proceedings SPIE 11266, Laser Resonators, Microresonators, and Beam Control XXII). DOI: 10.1117/12.2545005

    Abstract: Diode-side pump Nd:YAG rod modules are widely available, reliable and commercially very attractive for building continuous-wave solid-state lasers in the 10-1000 W range. Newer technologies such as fiber or thin disk lasers are generally much more expensive but have the benefit of better beam quality and higher output powers if necessary. By using well-known techniques for designing dynamically stable resonators (DSRs), lasers with high extraction efficiency and high beam quality (fundamental mode, TEM00) can be obtained also with diode side-pumped modules. However, a successful project for a dynamic stable laser depends critically on the correct choice of the fundamental mode diameter within the rod. DSR design rules are based on the beam waist, w3, at the rod principal planes by considering the rod as a thin thermal lens, which differs significantly from real resonators. Here we give guidelines and criteria on how to establish the correct diameter in each case. Using off-the-shelf 75 W Nd:YAG modules it was possible to obtain linearly polarized TEM00-mode output of 30 W with M2=1.08 from a single module, M2=1.2 and 76.5 W of output power using two modules and 100.5 W of polarized, continuous output with M2=1.8. A single-frequency ring laser was also built, using two modules, generating 51.6 W of fundamental wave single-frequency output.

    Palavras-Chave: neodymium lasers; yttrium compounds; resonators; diode-pumped solid state lasers

    Como referenciar este item
    Icon

  • IPEN-DOC 27330

    FERREIRA, MERILYN S. ; PASK, HELEN M.; WETTER, NIKLAUS U. . Nd:YLF/KGW intracavity Raman laser in DBMC configuration at 1147 and 1163 nm in TEM00. In: CLARKSON, W. ANDREW (Ed.); SHORI, RAMESH K. (Ed.) SPIE PHOTONICS WEST; SPIE LASE, February 1-6, 2020, San Francisco, USA. Proceedings... Washington, USA: SPIE, 2020. p. 112590K-1 - 112590K-7. (Proceedings SPIE 11259, Solid State Lasers XXIX: Technology and Devices). DOI: 10.1117/12.2545092

    Abstract: A Nd:YLF / KGW intracavity Raman laser in DBMC (double-beam-mode-controlling) configuration has been investigated in this work. The fundamental wavelength laser was generated using a Nd:YLF crystal pumped in DBMC configuration generating an emission wavelength of 1053 nm in σ-polarization. A VBG (volume-Bragg-grating) equipped diode emitting at 797 nm was used as pump source. The KGW crystal has two strong Raman lines, 768 cm-1 and 901 cm-1, generating two Raman wavelengths at 1147 nm and 1163 nm, respectively. The DBMC technique allows to produce TEM00 stable output in a side-pumped configuration with no requirement to introduce any additional mode selection technique, thus achieving high efficiency for fundamental TEM00 operation. The high power density of the fundamental laser combined with intracavity Stokes conversion produces an efficient Raman laser. Allying both techniques, the Nd:YLF in DBMC configuration and the intracavity Raman generation, it was possible to generate an output power at 1163 nm of 3.2 W corresponding to a diode-to-Raman conversion efficiency of 8% with slope efficiency of 8.8 %. For the emission at 1147 nm, 3.5 W of output power was achieved with a diode-to-Raman conversion efficiency of 11% and slope efficiency of 9%. The beam quality was M2 =1.9 and 1.1 in the horizontal and vertical direction, respectively. This is, to our knowledge, the first report of a side-pumped Nd:YLF/KGW intracavity Raman laser in DBMC configuration.

    Palavras-Chave: raman spectra; raman effect; optical pumping; diode-pumped solid state lasers

    Como referenciar este item
    Icon

  • IPEN-DOC 27321

    MAZIERO, J.S. ; ROGERO, S.O. ; DAMASCENO, K.C. ; ORMENIO, M.B. ; CAVALCANTE, A.K. ; MARTINI, G.A. ; BATISTA, J.G.S. ; KATTI, K.V.; LUGAO, A.B. ; ROGERO, J.R. . Avaliação da toxicidade de nanopartículas de prata estabilizadas com goma arábica. In: WORKSHOP DE BIOMATERIAIS, ENGENHARIA DE TECIDOS E ORGÃOS ARTIFICIAIS, 6th, October 29-31, 2019, São Paulo, SP. Proceedings... 2019. p. 403-413.

    Abstract: As nanopartículas de prata (NPAg), devido a seus diversos atributos (formato variado, elevada área superficial e alto poder bactericida), vem sendo amplamente utilizadas em diversos setores da indústria. Esta utilização abrangente, tem provocado grande preocupação, quanto aos impactos e riscos potenciais que as NPAg podem causar ao meio ambiente e à saúde humana. Este trabalho teve como objetivo verificar a toxicidade de uma amostra de NPAg estabilizada com Goma Arábica e reduzida com Tri-Alanina, utilizando ensaios in vitro e in vivo. O teste in vitro de citotoxicidade, foi realizado seguindo a norma ISO 10993 - 5, em células da linhagem NCTC-L929; os ensaios in vivo de ecotoxicidade aguda, de acordo com a norma brasileira ABNT NBR 12713, utilizando como organismo teste a Daphnia similis; e embriotoxicidade aguda de acordo com o protocolo da OECD 236, utilizando como organismo teste o Danio rerio. Os resultados obtidos foram: IC50 de 2,61 mg L-1, CE50 de 6,55 μg L-1 e CL50 de 673 μg L-1. Os organismos aquáticos apresentaram maior sensibilidade às NPAg do que as células em cultura, elevando a importância de se realizar mais estudos em várias espécies de interesse biológico. Além disso, mostra-se necessário verificar o descarte apropriado dessas nanopartículas, visto que no Brasil ainda não há legislações que quantifiquem os limites permissíveis para esse descarte.

    Palavras-Chave: fishes; seafood; gum acacia; daphnia; silver; nanoparticles; toxicity

    Como referenciar este item
    Icon

  • IPEN-DOC 27107

    PEREIRA, VIVIAM S.M.; ANTUNES, RENATO A.; OLIVEIRA, MARA C.L. de; CORREA, OLANDIR V. . Efeito de tratamentos de envelhecimento sobre a resistência à corrosão da liga de magnésio AZ91D / Ageing heat treatments effect on the corrosion resistance of the AZ91D magnesium alloy. In: CONGRESSO INTERNACIONAL ANUAL DA ABM, 67th, July 31 - August 7, 2012, Rio de Janeiro, RJ. Proceedings... 2012. p. 192-202.

    Abstract: O efeito de tratamentos térmicos de envelhecimento (T6) sobre a resistência à corrosão da liga de magnésio AZ91D foi estudado. Amostras solubilizadas a 445°C por 24 h foram envelhecidas a 200 °C por tempos de 8 h, 16 h e 24 h. Todos os tratamentos foram realizados em forno mufla, sob atmosfera inerte (argônio), seguidos de resfriamento em água. Para observação das alterações microestruturais, utilizaram-se as técnicas de microscopia óptica e de MEV. O comportamento eletroquímico foi avaliado por ensaios de espectroscopia de impedância eletroquímica e de polarização potenciodinâmica, utilizando-se solução de Hanks, a 37 °C como eletrólito. O período de imersão foi de 7 dias. Com o tratamento de solubilização, ocorreu a dissolução do constituinte eutético, restando somente a matriz (fase α-Mg) saturada com alumínio, juntamente de resquícios de β- Mg17Al12. Com o tratamento de envelhecimento foram observados precipitados ricos em alumínio (β-Mg17Al12) sobre a matriz. A amostra envelhecida por 8 h foi a que mostrou menor valor de resistência à corrosão; as amostras tratadas por 16 h e 24 h apresentaram valores de impedância semelhantes, sendo que a amostra envelhecida por 16 h apresentou o melhor desempenho.

    Palavras-Chave: corrosion resistance; heat treatments; magnesium alloys; compatibility; medical supplies; surgical materials

    Como referenciar este item
    Icon

  • IPEN-DOC 27083

    MARTINS, E.W. ; CARDOSO, J.V.; POTIENS, M.P.A. . Determination of computed tomography quantities using a new pediatric phantom. In: INTERNATIONAL CONFERENCE ON RADIATION PROTECTION IN MEDICINE: ACHIEVING CHANGE IN PRACTICE, December 11-15, 2017, Vienna, Austria. Proceedings... Vienna, Austria: International Atomic Energy Agency, 2018. p. 1-5.

    Abstract: A computed tomography pediatric head phantom that uses special materials to simulate the cortical and the cancellous bone was developed. This paper shows its behavior to determine the specific computed tomography radiation quantities at two calibration laboratory, the LCI-IPEN, Brazil and LMRI-IST, Portugal. The specific quantities measured were: air kerma index(Ca,100), weighted air kerma index (Cw), average volumetric air kerma index (Cvol) and the air kerma- lenght product (PKL). The reference radiation qualities used in both laboratories were the radiation qualities recommended by the norm IEC 61267 (RQT8, RQT9 e RQT10) to computed tomography dosimetry measurements. The calculated values of CW show attenuation of 11%, 13% and 10% for the qualities RQT 8, RQT 9 and RQT 10, respectively, from cortical to cancellous bone.

    Palavras-Chave: phantoms; pediatrics; computerized tomography; kerma

    Como referenciar este item
    Icon

  • IPEN-DOC 27080

    GERALDO, BIANCA ; VICENTE, ROBERTO ; FERREIRA, ROBSON J. ; MADUAR, MARCELO F. ; GOES, MARCOS M. ; MARUMO, JULIO T. . Radiochemical method for characterization of the filter cartridges from the IEA-R1 reactor. In: ANNUAL WASTE MANAGEMENT CONFERENCE, March 6-10, 2016, Phoenix, Arizona, USA. Proceedings... Tempe, Arizona, USA: Waste Management Symposia, 2016. p. 1-5.

    Abstract: The filter cartridges used in water purification system of the IEA-R1 research reactor become radioactive waste after the end of their useful life. The characterization of this waste is one step in their management, which aims at identifying and quantifying the radionuclides present, including those known as "difficult to measure" (DTM) radionuclides. Wastes from nuclear reactors contain fission and activation products and transuranic elements, only few of them emitting gamma radiation measurable by simple gamma spectrometry methods. In routine waste management activities, the concentrations of the DTM can only be estimated by indirect methods such as scaling factors. The method of the scaling factors uses empirically determined proportions between the concentrations of DTM radionuclides and that of easily measurable gamma emitters called key nuclides (KN), to calculate DTM concentrations. Determining the scaling factors for the filter cartridges is a hard task when the number of samples is large, not only because the preparation of samples is difficult but also because the number of radionuclides to analyze is large. If it can be demonstrated that DTM and KN are both distributed evenly in the filters, less samples from each filter are necessary, reducing lab work. The aim of this paper is to present the results of the assessment of homogeneity along the filter cartridges by gamma spectrometry of chemically reduced samples. Five thin slices of five filters were burnt and the ashes quantitatively dissolved and the activity concentration of the solutions determined by gamma spectrometry.

    Palavras-Chave: concentration ratio; filters; purification; radioactive waste management; radiochemistry; radioisotopes; research reactors; service life; water treatment

    Como referenciar este item
    Icon

  • IPEN-DOC 27079

    FERREIRA, EDUARDO ; VICENTE, ROBERTO ; TURRILLAS, XABIER; YOKAICHIYA, FABIANO; FRANCO, MARGARETH ; MARTINEZ, LUIS G. ; CARVALHO, ALEXANDRE; MARUMO, JULIO T. . Effects of gamma radiation on cementitious materials in repository environment. In: ANNUAL WASTE MANAGEMENT CONFERENCE, March 6-10, 2016, Phoenix, Arizona, USA. Proceedings... Tempe, Arizona, USA: Waste Management Symposia, 2016. p. 1-10.

    Abstract: Cementitious materials are widely used in the management of radioactive waste and have to perform as required for the period of service life of the installation. In order to assess the long term durability of cement paste in a deep borehole for radioactive wastes, specimens were casted in laboratory and exposed to a gamma radiation field. The effects of the radiation in the specimens were evaluated by X-Ray Diffraction, as changes observed in the mineralogy and microstructure of the material after irradiation doses varying between 0 (without radiation) and 10 MGy. It was observed that the specimens exposed to higher doses of gamma radiation (up to 3MGy) presented differences between surface and core, when compared with the samples with no radiation or exposed to low doses. These results are important to model the behavior of cementitious materials under the conditions expected in a borehole repository and to provide data for the safety assessment of the installation.

    Palavras-Chave: boreholes; cements; comparative evaluations; gamma radiation; microstructure; nuclear materials management; radiation doses; radioactive wastes; risk assessment; service life; wear resistance; x-ray diffraction

    Como referenciar este item
    Icon

  • IPEN-DOC 27071

    FERREIRA, E.S.; BENETTI, C.; ZEZELL, D.M. ; KATO, I.T.; ANA, P.A.. Efeitos da irradiação com laser de Er,Cr:YSGG na temperatura pulpar e superficial da dentina radicular. In: VIEIRA NETO, HUGO (Ed.); SOARES, ALCIMAR B. (Ed.); FÉLIX, RODRIGO P.B. da C. (Ed.); VIEIRA NETO, HUGO (Org.); MAIA, JOAQUIM M. (Org.); PICHORIM, SÉRGIO F. (Org.); GAMBA, HUMBERTO R. (Org.); COSTA, EDUARDO T. (Org.) CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 25., 17-20 de outubro, 2016, Foz do Iguaçu, PR. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2016. p. 1937-1940.

    Abstract: Tendo em vista o envelhecimento da população e a permanência dos dentes na cavidade oral, observou-se um aumento da incidência da cárie radicular em idosos. Os lasers de érbio podem ser usados para prevenção de cárie; contudo, ainda não são estabelecidos parâmetros de irradiação que sejam seguros para os tecidos pulpares e periodontais e que sejam efetivos para ocasionar alterações químicas na superfície da dentina. Este estudo avaliou os efeitos da irradiação da dentina radicular com laserde Er,Cr:YSGG na temperatura pulpar e superficial da dentina, buscando-se determinar parâmetros de irradiação seguros e efetivos para futura aplicação clínica. Para tal, foi realizado um estudo in vitro randomizado com duas fases experimentais. Na primeira fase, 30 blocos de dentina radicular bovina foram empregados para avaliar a temperatura superficial ocasionada por um único pulso laser empregando-se termografia no infravermelho, enquanto que, na segunda fase experimental, 30 dentes incisivos inferiores humanos foram empregados para avaliação da temperatura pulpar durante as irradiações por 10 segundos empregando-se termopares de resposta rápida. As irradiações foram efetuadas com laser de Er,Cr:YSGG,  = 2,78 μm, 20 Hz, sem refrigeração, com potências médias de 0,1 W, 0,25 W e 0,5 W, o que resultou em densidades de energia de 2,4 J/cm2, 6 J/cm2 e 12 J/cm2, respectivamente. Observou-se variações de temperatura superficial de 61  26 oC, 75  34 oC e 172  36 oC para os grupos irradiados com potência média de 0,1 W, 0,25 W e 0,5 W, respectivamente. Foram registradas elevações médias de temperatura pulpar de 0,81 ± 0,4 oC, 1,76 ± 0,7 oC e 2,95 ± 1,33 oC, para os grupos irradiados com potência média de 0,1 W, 0,25 W e 0,50 W, respectivamente. Concluiu-se que o laser de Er,Cr:YSGG promove elevações de temperatura superficiais que indicam a ocorrência de transformações químicas na superfície da dentina radicular; contudo, dos parâmetros testados, se considerarmos as elevações de temperatura pulpar, a potência média de 0,25 W é a que se apresenta mais promissora para futuro uso para prevenção da cárie radicular.

    Palavras-Chave: dentistry; dentin; lasers; radiation effects; temperature dependence

    Como referenciar este item
    Icon

  • IPEN-DOC 27070

    GONÇALVES, KARINA de O.; SILVA, MONICA N. da; COURROL, LILIA C. . Síntese de nanopartículas de ouro funcionalizadas com ácido aminolevulínico e laser de pulsos ultracurtos. In: VIEIRA NETO, HUGO (Ed.); SOARES, ALCIMAR B. (Ed.); FÉLIX, RODRIGO P.B. da C. (Ed.); VIEIRA NETO, HUGO (Org.); MAIA, JOAQUIM M. (Org.); PICHORIM, SÉRGIO F. (Org.); GAMBA, HUMBERTO R. (Org.); COSTA, EDUARDO T. (Org.) CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 25., 17-20 de outubro, 2016, Foz do Iguaçu, PR. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2016. p. 1913-1916.

    Abstract: As nanopartículas de ouro apresentam inúmeras aplicações na medicina. As diferenças de tamanho, forma e propriedades de superfície, fazem com que suas aplicações se tornem versáteis, como por exemplo, a terapia fototérmica e o rastreamento de tumores (biomarcadores). Foi recentemente demonstrado na literatura que a incorporação de nanopartículas de ouro na estrutura do ácido 5-aminolevulínco (5-ALA) melhora as propriedades fotodinâmicas do fármaco. O estudo com laser ocorreu visando à possibilidade de modificação no formato das nanopartículas, de esféricas para outras formas, entre elas bastões e prismas que resultam em bandas de plasmons de comprimentos de onda maiores, uma vez que nanopartículas com formato mais cilíndrico apresentam uma janela na região da janela óptica do tecido biológico e desta forma a luz aplicada em PDT teria maior profundidade de penetração no tecido. Assim propomos neste estudo, sintetizar nanopartículas de ouro com 5-ALA, para realizar o diagnóstico e a terapia (Teranóstica) de doenças com crescimento não controlável, de uma forma mais simples, menos invasiva e mais barata.

    Palavras-Chave: gold; nanoparticles; arteriosclerosis; phototherapy; biological markers

    Como referenciar este item
    Icon

  • IPEN-DOC 27069

    PROVASI, C.; CASSIMIRO-SILVA, P.F.; ANA, P.A. da; ZEZELL, D.M. ; GOMES, A.S.L.; LINS, E.C.. Estudo da espectroscopia de reflexão com radiações visíveis e infravermelhas para discriminação de tecidos pulpares humanos sadios e patológicos. In: VIEIRA NETO, HUGO (Ed.); SOARES, ALCIMAR B. (Ed.); FÉLIX, RODRIGO P.B. da C. (Ed.); VIEIRA NETO, HUGO (Org.); MAIA, JOAQUIM M. (Org.); PICHORIM, SÉRGIO F. (Org.); GAMBA, HUMBERTO R. (Org.); COSTA, EDUARDO T. (Org.) CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 25., 17-20 de outubro, 2016, Foz do Iguaçu, PR. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2016. p. 1909-1912.

    Abstract: A polpa dental é o tecido mais interno do dente. Sua principal função é garantir a dentinogênese e a sensibilidade dental, e por essa razão a informação clínica sobre a saúde da polpa é relevante. Polpas diagnosticadas como não-vitais são encaminhadas para um tratamento endodôntico agressivo, baseado na remoção de todo tecido degradado. Por esse motivo, deve-se haver um esforço em minimizar o número de falsos diagnósticos clínicos da vitalidade pulpar, na intenção de preservar a integridade do paciente. Esse estudo propõe a espectroscopia no visível e no infravermelho como método de melhorar a precisão no diagnóstico do status pulpar. Ele é baseado em confrontar a reflexão óptica dos tecidos no espectro do visível (VIS) e do infravermelho próximo (NIR) (350nm a 1.700nm) no intuito de discriminar polpas humanas vitais de outras polpas sintomáticas de pulpite. A Análise dos Componentes Principais (PCA) sobre os espectros de reflexão ainda propôs modelos matemáticos de diferenciação dos grupos. Os resultados revelaram que a reflexão óptica pode discriminar o status da vitalidade de polpas humanas vivas; e a análise estatística da PCA revelou precisão de acerto de 100% para radiações NIR e 95% para radiações VIS.

    Palavras-Chave: dentistry; teeth; visible radiation; infrared radiation; spectroscopy

    Como referenciar este item
    Icon

  • IPEN-DOC 27068

    PEREIRA, D.L. ; FREITAS, A.Z. ; ZEZELL, D.M. ; ANA, P.A.. Uso da tomografia por coerência óptica no monitoramento de lesões de erosão e abrasão em dentina. In: VIEIRA NETO, HUGO (Ed.); SOARES, ALCIMAR B. (Ed.); FÉLIX, RODRIGO P.B. da C. (Ed.); VIEIRA NETO, HUGO (Org.); MAIA, JOAQUIM M. (Org.); PICHORIM, SÉRGIO F. (Org.); GAMBA, HUMBERTO R. (Org.); COSTA, EDUARDO T. (Org.) CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 25., 17-20 de outubro, 2016, Foz do Iguaçu, PR. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2016. p. 1861-1864.

    Abstract: O objetivo deste trabalho foi avaliar o potencial da tomografia por coerência óptica (OCT) para o diagnóstico precoce e monitoramento de lesões de erosão e abrasão em dentina. Para isso, foi realizado um estudo in vitro com 192 blocos de dentina radicular bovina de 8 mm2, distribuídos aleatoriamente em quatro grupos experimentais (n = 48): G1- sem tratamento; G2- tratamento com flúor fosfato acidulado (FFA, 1,23% F-, pH = 3,3–3,9); G3- irradiação com laser de Nd:YAG (1064nm, 0,6W, 10Hz, 84,9J/cm2); G4- aplicação de FFA, seguida de irradiação com laser de Nd:YAG. Após os tratamentos, as amostras foram submetidas a um desafio de erosão e abrasão por escovação (Sprite Zero, pH=2,6, 90s, 4x/dia) e remineralização (saliva artificial, pH=7) durante 15 dias, sendo avaliadas por OCT em 5 momentos distintos: antes e após os tratamentos, e após 5, 10 e 15 dias de desafio. Foi possível observar o desenvolvimento e evolução das lesões de erosão/abrasão e também foi possível relacionar a desmineralização do tecido decorrente do processo de erosão/abrasão com o coeficiente de atenuação óptica.

    Palavras-Chave: dentistry; teeth; dentin; abrasion; diagnosis; coherent radiation; tomography

    Como referenciar este item
    Icon

  • IPEN-DOC 27067

    OLIVEIRA, L.Z.; WATANABE, T.E.; GOUVEIA, D.S. ; BRESSIANI, A.H.A. ; RIBEIRO, C.. Estudo da síntese para obtenção de hidroxiapatita em meio de colágeno. In: VIEIRA NETO, HUGO (Ed.); SOARES, ALCIMAR B. (Ed.); FÉLIX, RODRIGO P.B. da C. (Ed.); VIEIRA NETO, HUGO (Org.); MAIA, JOAQUIM M. (Org.); PICHORIM, SÉRGIO F. (Org.); GAMBA, HUMBERTO R. (Org.); COSTA, EDUARDO T. (Org.) CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 25., 17-20 de outubro, 2016, Foz do Iguaçu, PR. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Engenharia Biomédica, 2016. p. 251-254.

    Abstract: A obtenção da hidroxiapatita - HA nanoestruturada pode exigir modificações nas técnicas convencionais de síntese a fim de mimetizar estruturalmente as bioapatitas. A técnica de neutralização já vem sendo explorada em função de sua simplicidade e versatilidade, mas sua reprodutibilidade nem sempre é garantida, sugerindo a formação de fases intermediárias precursoras da HA, e algumas vezes outras fases, como o óxido de cálcio, além do alto estado de aglomeração de suas partículas. Com intuito de obter pós nanométricos de natureza dispersa e garantir a estabilidade da HA foi adicionado colágeno hidrolisado (4% em massa) ao meio de precipitação, variável ainda pouco explorada em processos de síntese. Os pós obtidos foram caracterizados por DRX, sendo observada a presença da fase pura e aumento da cristalinidade após calcinação a 800oC/3h, ainda verificou-se maior perda de massa para esta HA quando comparada a técnica clássica de precipitação (sem colágeno). Os resultados obtidos indicaram a viabilidade da metodologia para obtenção da HA, confirmando a natureza nanométrica dos pós e estabilidade da fase, logo após a síntese, e também após calcinação. A HA sintetizada apresentou cerca de 95% de densificação, microestrutura que pôde ser comprovada por MEV, além de manter sua estrutura cristalina, sem a formação de fase secundária, conforme observado por DRX, após sinterização a 1100oC/1h. A metodologia de síntese, em meio de colágeno, proporcionou a obtenção de pós de HA nanométrica de adequada sinterabilidade e estabilidade, podendo gerar microestruturas densas, mantendo fase única.

    Palavras-Chave: synthesis; apatites; calcium phosphates; collagen

    Como referenciar este item
    Icon

  • IPEN-DOC 27061

    TERADA, M.; QUEIROZ, F.M.; COSTENARO, H.; OLIVIER, M.G.; COSTA, I. ; MELO, H.G. de. Effect of cerium (III) on the corrosion protection properties of the film formed on the AA2524-T3 alloy by hydrothermal treatments. In: EUROPEAN CORROSION CONGRESS, September 11-15, 2016, Montpellier, France. Proceedings... Frankfurt, Germany: European Federation of Corrosion, 2016. p. 1-9.

    Abstract: Many industries use chromium-based anodizing processes with a subsequent sealing post-treatment containing hexavalent chromium ions to protect Al alloys. However, this method of protection causes large environmental and health related problems. This has encouraged the search for new surface treatments for metals with the requirements of effective protection against corrosion and generation of non-toxic residues to the environment. Recent studies are pointing towards chromium free anodizing processes, specifically the tartaric-sulfuric acid (TSA) one, as a viable alternative. Besides, sealing treatments of the Al anodic layer in chromate solutions are another source of toxic residues and their replacement for environmentally friendly alternatives are also of great interest. Surface treatments with cerium ions are being largely studied for the corrosion protection of Al alloys due to their good anticorrosion properties associated to the lack of toxic residues generated. In this investigation, a hydrothermal treatment in aqueous solution with cerium ions has been proposed as a post-treatment for TSA anodizing, and its effects on the AA2524-T3 alloy corrosion resistance investigated. This alloy presents a chemical composition similar to the AA2024 but with lower and more controlled amounts of alloying elements. The sealing treatment was carried out by immersion in aqueous solutions with cerium ions at the boiling temperature. The effect of Ce on the characteristics of the surface film formed, such as morphology and corrosion resistance, was investigated by SEM and electrochemical impedance spectroscopy. The results were compared to those of sealing in boiling water. The results showed that the sealing treatment in solution with Ce(III) ions presented a less stable behavior than the sealing with only boiling water. However, the results of the EIS experiments showed recovery of the protective properties of the system, indicating that some self-healing properties must be imparted to the system.

    Palavras-Chave: aluminium alloys; cerium ions; sealing materials; surface treatments; sol-gel process; sulfuric acid

    Como referenciar este item
    Icon

  • IPEN-DOC 27051

    LOPES, HENRIQUE D.; NUNES, EDUARDO; COLOSIO, MARCO; ROSSI, JESUALDO . PM conversion study for a transmission component: scuffing wear ranking of nitrided Astaloy CrA and reference CQT 16MnCrS5 Rollers. In: WORLD PM2016 CONGRESS AND EXHIBITION, October 9-13, 2016, Hamburg, Germany. Proceedings... Chantilly, France: European Powder Metallurgy Association, 2016. p. 1-7.

    Abstract: Net shape manufacturing advantages and its cost effectiveness is well known for sintered structural parts for many automotive applications. Combined with cost effective material solutions, plus smart secondary processes, and finally leading to higher product performance, PM technology can add even more value to customer processes and end user applications. This paper describes the conversion study of a manual transmission component from wrought to pm steel, while presenting the results of comparing the wear performance when subjected to moderate forces and high sliding velocities. The authors analyzed the behavior of PM based Cr plus nitriding (gas or plasma) specimens in comparison with a wrought steel plus carburizing. The component lifetime and reliability was evaluated according to the IRG-diagram. The final conclusion is that the PM material has better wear performance than the current wrought steel component.

    Palavras-Chave: testing; nitrides; microhardness; automotive industry; wear resistance

    Como referenciar este item
    Icon

  • IPEN-DOC 27048

    CARDOZO, NELSON X. ; OMI, NELSON M. ; AMBIEL, JOSE J. ; FEHER, ANSELMO ; NAPOLITANO, CELIA M. ; SOMESSARI, SAMIR L. ; CALVO, WILSON A.P. . Development of an irradiation system for radioisotope production applied to industrial process tomography. In: WORLD CONGRESS ON INDUSTRIAL PROCESS TOMOGRAPHY, 8th, September 26-29, 2016, Foz do Iguaçu, PR. Proceedings... International Society for Industrial Process Tomography, 2016.

    Abstract: Among the various applications of radioisotopes, the use of radiotracers is considered the most important in diagnosing operation and troubleshooting of industrial process plants in chemical and petrochemical companies. The radiotracers are used in analytical procedures to obtain qualitative and quantitative data systems, in physical and physicochemical studies transfers. In the production of gaseous radioisotopes used as tracers in industrial process measurements, argon-41 (41Ar) and krypton-79 (79Kr) have low reactivity with other chemical elements. 41Ar is a transmitter range with high-energy (1.29MeV) and a high percentage of this energy transformation (99.1%), resulting in relatively small quantities required in relation to the other, for an efficient detection, even in large thicknesses components. Nowadays, the production of gaseous radioisotopes in nuclear research reactors is performed in small quantities (batches), through quartz ampoules containing natural gas 40Ar or 78Kr. In this sense, the aim of this study is to develop an irradiation system for gaseous radioisotope production in continuous scale, applied in industrial applications of emission tomography and flow measurement. The irradiation system may produce 41Ar with activity of 7.4x1011Bq (20Ci) per irradiation cycle, through the Reactor IEA-R1 with 4.5MW and average thermal neutron flux of 4.71x1013 ncm-2s-1 to meet an existing demand in NDT and inspections companies, and even needed by the Radiation Technology Centre, at IPEN/CNEN-SP. The irradiation system consists of an aluminium irradiation capsule, transfer lines, needle valves, stripy connections, quick connectors, manometer, vacuum system, dewar, lead shielding, storage and transport cylinders, among other components. The irradiation system was approved in the leakage and stability tests (bubble test, pressurization, evacuation and with leak detector equipment SPECTRON 600 T). In the experimental production, alanine dosimeters were distributed into various components of the irradiation system, obtaining 1.07x1011Bq (2.9Ci) of 41Ar. In addition, exposure rates were determined in the lead shielding wall, in which the liquefied radioactive gas was concentrated, and in the storage and transport cylinders after 41Ar was transferred, by the portable radiation meter Teletector ® Probe 6150 AD-t/H.

    Palavras-Chave: radioisotopes; production; processing; argon 41; irradiation devices

    Como referenciar este item
    Icon

  • IPEN-DOC 27044

    KIM, HAE Y.; HARAGUCHI, M.I.; CALVO, W.A.P. . Comparison of industrial tomography algorithms for gamma scanning 2-D reconstruction. In: WORLD CONGRESS ON INDUSTRIAL PROCESS TOMOGRAPHY, 8th, September 26-29, 2016, Foz do Iguaçu, PR. Proceedings... International Society for Industrial Process Tomography, 2016. p. 1-7.

    Abstract: In this paper, we compare different industrial tomography algorithms to present the result of gamma scanning as a two-dimensional image of density distribution. In two-dimensional gamma scanning, an unconventional irradiation geometry is used and consequently many classic image reconstruction algorithms cannot be used. We tested two iterative reconstruction methods: ART (Algebraic Reconstruction Technique) and MART (Multiplicative Algebraic Reconstruction Technique). The iteration steps of both methods were intercalated with various filters: mean filter, median filter, anisotropic diffusion and total variation. The use of these filters greatly improves the quality of reconstruction. We report the obtained results.

    Palavras-Chave: tomography; algorithms; algebra; gamma sources

    Como referenciar este item
    Icon

  • IPEN-DOC 27049

    SANTOS, RENATA S. da S.; SILVA, MARCOS P. de A.; HOELZEMANN, JUDITH J.; SILVA, CLAUDIO M.S. e; LANDULFO, EDUARDO ; LOPES, FABIO J. da S. . Study of cirrus clouds physical properties using the Lidar-DUSTER system and radiosounding data at Natal/RN- Brazil. In: ALBUQUERQUE, TACIANA T.A. (Ed.); ANDRADE, MARIA DE F. (Ed.); SANTOS, JANE M. (Ed.) AIR POLLUTION CONFERENCE BRAZIL; COMMUNITY MODELING AND ANALYSIS SYSTEM SOUTH AMERICA, 4th, July 22-24, 2019, Belo Horizonte, MG. Proceedings... Belo Horizonte, MG: SEAD, Treinamentos e Coaching, 2019. p. 355-360.

    Abstract: Cirrus clouds are classified as the highest clouds in the atmosphere occurring generally from 7 to 18 km, depending on the global region of appearance, and have necessarily ice crystals in their composition. They still have an uncertain influence role in climate, therefore are seen as important atmospheric elements to be studied. Lidar systems (LIght Detecting and Ranging) have shown efficiency in the collection of cirrus characteristics which can help in its better parameterization in climatic and atmospheric models. In this work a collection of physical characteristics of cirrus was carried out, for January and February of 2017 and 2018, at Natal’s atmosphere using Lidar DUSTER’s data (5.84 S 35.20 W), a partnership UFRN/IPEN-SP. Morphological patterns of that clouds have been observed according to its heights as well as variations. Clouds with thinner depths and tenuous are observed at the top regions of troposphere, around 16.0 km. Otherwise, clouds with bigger vertical extensions are found around 12.0 km. The height of occurrence of cirrus in Natal, for the considered period vary from a minimum height of 7.0 km to a maximum of 16.0 km. Cirrus clouds most frequently occurred at a medium height of 12.0 km, considering both years. Those clouds had a considerable representativeness over the city atmosphere corresponding to 67% of total Lidar measured days. Besides the Lidar system was also used data from radiosounding technique. The behavior of the meteorological variables such as relative humidity was analyzed for the regions in which were found cirrus by the Lidar DUSTER. Within the region limits was verified a significant increase of relative humidity values. This behavior is not observed in lower regions where there is not any clouds presence as well in a day without cirrus appearance. In addition, future analyzes of the potential equivalent temperature profile will be studied in order to verify the effect of the cirrus clouds occurring in the temperature and humidity profile in a combined manner. Also, is expected to evaluate the possible impacts of cold air intrusion of the stratosphere in layers of cirrus clouds. In conclusion, Lidar DUSTER data demonstrates to be efficient in the identification of cirrus clouds over Natal’s atmosphere contributing to a better comprehension of its behavior and role in the region of study.

    Palavras-Chave: optical radar; clouds; air pollution

    Como referenciar este item
    Icon

  • IPEN-DOC 27047

    RAE, CRISTINA T.S.; HOELZEMANN, JUDITH J.; OLIVEIRA, DANIEL C.F.S.; SILVA, MARCOS P.A.; LOPES, FABIO J.S. ; LANDULFO, EDUARDO . Atmospheric aerosol behavior study in Natal city through LIDAR backscatter profiles and random errors propagation analysis by Monte Carlo method. In: ALBUQUERQUE, TACIANA T.A. (Ed.); ANDRADE, MARIA DE F. (Ed.); SANTOS, JANE M. (Ed.) AIR POLLUTION CONFERENCE BRAZIL; COMMUNITY MODELING AND ANALYSIS SYSTEM SOUTH AMERICA, 4th, July 22-24, 2019, Belo Horizonte, MG. Proceedings... Belo Horizonte, MG: SEAD, Treinamentos e Coaching, 2019. p. 328-330.

    Abstract: The physical and optical interaction of aerosols in atmospheric processes are complex and have high temporal and spatial variability, representing uncertainties as, for example, the aerosol particles influence on the atmosphere energetic balance. The Duster is a LIDAR system (Light Detection and Ranging) located in Natal / RN, capable of working with four detection channels (355 nm, 532 nm p, 532 nm s and 1064 nm). Duster sends pulses of laser light to the atmosphere and detects the return signal that results from the interaction of light with aerosol particles in the atmosphere. The signal detected by the system is represented by the LIDAR equation, which describes the optical properties and the system geometric parameters. The solution for this equation is obtained by the Klett-Fernald-Sasano Inversion Method (KFS), which extracts the inverted optical properties as backscattering (β) and extinction (α) profiles. The present work brings the result of analysis in backscatter profiles of the LIDAR signal in channel 532 nm during the aerosol Monitoring Campaign Long-Range Transportation Over Natal II (MOLOTOV II) that occurred from November 2017 to February 2018. We applied the Monte Carlo method for the analysis of the error in DUSTER measurements, which employs random numbers sequences. Two days of signal measurements were selected, to deal with four groups files, within approximately 30 min each group (frequency acquisition every 10 seconds). N synthetic profiles, as height function, with a random number generator, were created. Algorithms were performed, which removed the measurements clouds, the dark profiles, the background noise and generated the Range Corrected Signal (RCS). The KFS was applied to the synthetic profiles to obtain a set of N solutions (backscatter and extinction coefficient profiles). The results show that the N optical property profiles presented a considerable variability, characterized by their standard deviation. This variability, calculated as the height function, is the random error estimate of the LIDAR signal associated with the inversion procedure. The observed aerosols, according to information from the Hysplit trajectory model, were originated from the Sahara desert.

    Palavras-Chave: optical radar; backscattering; errors; monte carlo method

    Como referenciar este item
    Icon

  • IPEN-DOC 27046

    OLIVEIRA, DANIEL C.F. dos S.; HOELZEMANN, JUDITH J.; LANDULFO, EDUARDO ; ALADOS-ARBOLEDAS, LUCAS; GUERRERO-RASCADO, JUAN L.. Aerosol optical properties in the atmosphere of Natal/Brazil by an AERONET network Sun-photometer. In: ALBUQUERQUE, TACIANA T.A. (Ed.); ANDRADE, MARIA DE F. (Ed.); SANTOS, JANE M. (Ed.) AIR POLLUTION CONFERENCE BRAZIL; COMMUNITY MODELING AND ANALYSIS SYSTEM SOUTH AMERICA, 4th, July 22-24, 2019, Belo Horizonte, MG. Proceedings... Belo Horizonte, MG: SEAD, Treinamentos e Coaching, 2019. p. 319-324.

    Abstract: The study of atmospheric aerosols contributes to the understanding of radiative forcing and global warming. In addition, aerosols may influence atmospheric chemistry, visibility, precipitation and human health. Since 2016, Natal (capital of Rio Grande do Norte, Brazil) has a Sun-photometer (CIMEL) of the RIMA-AERONET network that can identify the presence of biomass burning aerosols and desert dust from Africa. For this identification, it is aimed to characterize the optical properties of these aerosols present in the atmosphere of Natal. The level 1.5 data (version 3) provided by AERONET provide information on some aerosol characteristics such as Aerosol Optical Depth (AOD), Ångström Exponent (α), Single Scattering Albedo (SSA), Asymmetry Factor (g), Complex Refractive Index (N) and Volume Size Distribution (VSD). The analysis period was from August 2017 to March 2018. Aerosols were classified according to global climatologies and their optical properties were described. In addition, backward trajectories were modeled using the HYSPLIT model (version 4.8) to identify the predominant air masses origins. Aerosols present in the atmospheric column of Natal showed monthly mean AOD (500 nm)in the range of 0.10 to 0.(representing ~40%), monthly means of α (440-670 nm)between 0.6 and 0.8 (representing 30%), bimodal VSD with dominant coarse mode, SSA (440 nm) about 0.80, real part around 1.500, imaginary part ranging from 0.0125 to 0.0437 and g above 0.74. The classification showed mixed (60.4%), marine (30.7%) and mineral dust (8.9%) aerosols. The backward trajectories identified that, in about 51% of the cases, are originated from Africa.

    Palavras-Chave: satellite atmospheres; photometers; optical radar; atmospheres; optical properties; dusts; environment; environmental impacts; biomass; climatic change

    Como referenciar este item
    Icon

  • IPEN-DOC 27042

    GRANDISOLI, C.L.; ANA, P.A. da; COSTA, M.M.; ZEZELL, D.M. ; LINS, E.C.. Viabilidade da transiluminação dental como técnica de imageamento das estruturas internas do dente. In: CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 24., 13-17 de outubro, 2014, Uberlândia, MG. Anais... Bauru, SP: Canal 6, 2014. p. 2070-2073.

    Abstract: A Transiluminação Dental (TD) é uma técnica utilizada para obtenção de imagens das estruturas dos dentes que funciona através da detecção da radiação infravermelha transmitida através dos mesmos. Este trabalho visa apresentar a TD como técnica de imageamento das estruturas anatômicas internas do dente. Amostras de 16 dentes humanos foram divididas em grupos com espessuras entre 0.5 e 2.5 mm. Para captação das imagens foi utilizada uma câmera FPA InGaAs (900- 1700 nm; Xenics, Inc., Bélgica) e uma fonte de lâmpada halógena no infravermelho próximo (Ocean Optics, Inc., USA); além de filtros ópticos de 1000±10nm, 1100±10nm, 1200±10nm e 1300±50nm. Imagens foram capturadas para diferentes tempos de exposição do sensor da câmera. Os melhores resultados revelam a viabilidade de imageamento de estruturas de espessura de até 2,5 mm sem a utilização de filtros. Após a obtenção destes resultados, um experimento piloto foi realizado em mais 4 amostras de dentes íntegros a fim de detector a câmara pulpar dos dentes. Os resultados provaram a viabilidade da TD no imageamento dental.

    Palavras-Chave: dentistry; teeth; infrared radiation; dentin

    Como referenciar este item
    Icon

  • IPEN-DOC 27039

    GONÇALVES, KARINA de O.; SILVA, MONICA N. da; SICCHIERI, LETICIA B. ; SILVA, FLAVIA R. de O. ; COURROL, LILIA C. . Síntese verde de nanopartículas de ouro e aplicações no diagnóstico e terapia de aterosclerose. In: CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 24., 13-17 de outubro, 2014, Uberlândia, MG. Anais... Bauru, SP: Canal 6, 2014. p. 1874-1877.

    Abstract: As nanopartículas de ouro apresentam inúmeras aplicações na medicina, como por exemplo, a terapia fototérmica e o rastreamento de tumores (biomarcadores). Elas também podem ser utilizadas no transporte de drogas (drug delivery), genes e DNA. Foi recentemente demonstrada na literatura que a incorporação de nanopartículas de ouro na estrutura do ácido δ - aminolevulínco (ALA) melhora as propriedades fotodinâmicas da terapia. Neste estudo propomos estabelecer correlações entre alterações nas fluorescências da protoporfirina IX extraídas do sangue e o crescimento da placa de ateroma. Este estudo implica em determinar se as nanopartículas de ouro sintetizadas com ALA podem fornecer informações adicionais e permitir prever quais pacientes correm maiores riscos de doença cardíaca no futuro de forma não invasiva e de baixo custo.

    Palavras-Chave: nanoparticles; fluorescence; arteriosclerosis; protoporphyrins

    Como referenciar este item
    Icon

  • IPEN-DOC 27038

    SILVA, MONICA N. da; SICCHIERI, LETICIA B. ; SILVA, FLAVIA R. de O. ; GONÇALVES, KARINA de O.; ANDRADE, MAIRA F. de ; LANZONI, VALERIA P.; COURROL, LILIA C. . A análise da fluorescência do sangue de coelhos submetidos à dieta hipercolesterolêmica. In: CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 24., 13-17 de outubro, 2014, Uberlândia, MG. Anais... Bauru, SP: Canal 6, 2014. p. 1632-1635.

    Abstract: A aterosclerose é uma doença degenerativa crônica caracterizada pela presença de lesões com aspectos de placas ou ateromas em artérias de médio e grande calibre. É a causa primária de doenças cardiovasculares e infarto, que por sua vez representam a principal causa de morte por doença no mundo. Este estudo busca um potencial marcador de aterosclerose o que pode viabilizar um método diagnóstico minimamente invasivo e de baixo custo. Neste estudo coelhos da raça New Zeland foram submetidos à dieta hipercolesterolêmica. Em um primeiro estudo foram realizadas extrações do sangue e das artérias. Foi realizado o perfil metabólico dos coelhos após 20, 40 e 60 dias do início da dieta. As artérias excisadas foram analisadas por microscopia para verificação da instalação do processo aterosclerótico nos coelhos. No segundo experimento realizou-se a coleta de fezes semanalmente. Nosso objetivo foi à verificação das variações da quantidade de PPIX (protoporfirina IX) no sangue e nas fezes com o estadiamento da aterosclerose. Com as fezes obteve-se uma curva de calibração para a determinação da melhor quantidade de massa fecal para o melhor volume de acetona, para a extração da PPIX. O melhor resultado foi obtido com os valores 0,10 g de massa fecal para 400 microlitros de acetona. O estudo da extração da PPIX tanto no sangue e nas fezes mostrou o aumento da emissão de fluorescência da PPIX no grupo da indução hipercolesterolêmica, acompanhando o aumento dos valores de LDL (lipoproteína de baixa densidade). Este estudo identificou um potencial marcador de aterosclerose.

    Palavras-Chave: protoporphyrins; biological markers; arteriosclerosis; fluorescence

    Como referenciar este item
    Icon

  • IPEN-DOC 27026

    PEREIRA, T.M. ; DIEM, M.; BIRD, B.; MILJKOVIC, M.; ANA, P.A.; BACHMANN, L.; ZEZELL, D.M. . Caracterização por espectroscopia no infravermelho de colóides tireoidianos sadios e hiperplásicos. In: CONGRESSO BRASILEIRO DE ENGENHARIA BIOMÉDICA, 24., 13-17 de outubro, 2014, Uberlândia, MG. Anais... Bauru, SP: Canal 6, 2014. p. 1115-1118.

    Abstract: O presente trabalho mostra a caracterização da Tiroglobulina contidos nos colóides tireoidianos por espectroscopia no infravermelho. A produção da tiroglobulina é alterada em pacientes com Bócio Nodular. Assim, as informações bioquímicas desta glicoiodoproteina podem ser utilizada como indicador desta disfunção. Os resultados utilizando espectroscopia no infravermelho revela diferenças bioquímicas nas conformação da proteína, hormônios e carboidratos.

    Palavras-Chave: endocrine glands; thyroid; proteins; infrared spectrometers; diagnosis

    Como referenciar este item
    Icon

  • IPEN-DOC 27036

    PEREZ, CLARICE F.A.; SAHYUN, ADELIA ; FREITAS, KENIA A.M.. Study on the protection planning actions and response to nuclear or radiological emergency. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 1783-1787.

    Abstract: Nuclear or Radiological emergencies can have as a consequence the rise of Deterministic effects, in the population involved, and/or Stochastic effects due to their doses. In these situations, protective actions need to be done in order to keep the doses in the affected population below the levels of deterministic effects and protective actions that might reduce the risk of stochastic effects should be adopted, minimizing the doses to reasonably achievable levels. This work presents a comparative study between the publication of IAEA Safety Series 109 and the document of the International Atomic Energy Agency GSG-2 "Criteria for Use in Preparedness and Response for a Nuclear or Radiological Emergency" regarding the effective dose value system to be used as a basis to trigger protection actions in the Planning and Response to Nuclear or Radiological Emergencies that can reduce the risk of stochastic effects.

    Palavras-Chave: radiation protection; emergency plans; administrative procedures; radiation doses

    Como referenciar este item
    Icon

  • IPEN-DOC 23677

    CARNEIRO, J.C.G.G. ; ALVES, A.S. ; SANCHES, M.P. ; RODRIGUES, D.L. ; LEVY, D.S. ; SORDI, G.M.A.A. . Basic characterization of a radioactive facility and evaluation of risk agents. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 892-899.

    Abstract: This is an exploratory and descriptive study with qualitative and quantitative approaches to investigate the basic characterization of a Brazilian radioisotope production facility through ample knowledge of the workplace, workforce, task performed and identification of present risk agents in labor environment. The studied sample was composed by 102 workers distributed in eight work processes. Data were collected from April 2013 to July 2014 by applying questionnaire forms and complemented by interviews and observations. The descriptive statistical analysis included ANOVA test and non-parametric tests, among others. For the purpose of this study, there was adopted a significance level of 5% (p<0.05). The analysis of socio-demographic variables demonstrated that male gender predominated in total sample (74.5%) and the mean age of the workers was (51.8 ± 1.7) years. The largest percentage of the responders (70.6%) was technician-level workers. Regarding task-related exposure, there was considered that all groups presented the same exposure profile. At the workplace, there were identified 17 risk agents, including physical, chemical, biological, ergonomic and accident risks. The workforce was categorized into 3 risk groups according to relative frequency distribution of the occupational risks. Among the sixteen qualitative variables studied at the workplace, only three of them did not demonstrate relative frequency. The only variable that showed association with the three risk groups was the possibility of the contact with ionizing radiation. The study provided an overview of the perception of occupational risk at the facility. According to the results obtained by statistical analysis, most of the qualitative variables presented statistically significant association (p<0.001) related to the occurrence of occupational risks. Even though the workers may be potentially exposed to different risk agents, the ionizing radiation was the main physical risk factor observed in this facility.

    Palavras-Chave: nuclear facilities; occupational exposure; risk assessment; human factors; radioactive materials; radiations

    Como referenciar este item
    Icon

  • IPEN-DOC 27063

    SORDI, GIAN M. . Comments on the General IAEA Safety Requirements - Part 3 - and suggestions for the next publications. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 381-383.

    Abstract: The international recommendations in question are described 52 requirements specified from chapter 2 to 5. The first chapter states that the number of fundamental safety principles has been increased form 3 to 10. To implement these requirments, the IAEA mentions 14 main parties but it is not clear which party is responsible for each of the fundamental safety principles. Chapter 2 presents 5 general requirements for protection and safety and makes it clear the responsibilities and competence of the government and regulatory body. ; but the responsibilities and competence of the other 12 principal parties reported in requeriment 4 are not clear. Chapter 3, which includes 37 requirements, is the most extensive and deals with planned exposure situations. Due to its extension, chapter 3 is left for a future paper, in case my comments are considered of some value by the principal parties involved. Chapter 4, with 4 requirements, deals with emergency exposure situations; and in chapter 5, the 6 requirements are about existing exposure situations. As to the requirements exposed in chapters 1, 2, 4 and 5 I have verified that the responsibilities and competence of the government and the regulatory body are clearly specified, which is not true for the other 12 principal parties. It is concerning this specific matter that I have made comments and suggestions. I also discuss the matters that are not under the responsibility of the radiological protection services but of other parties. Could the radiation protection service as a whole or in part be delegated to others, including the attributions of registrants or licensees?

    Palavras-Chave: recommendations; radiation protection; reporting requirements; nuclear medicine

    Como referenciar este item
    Icon

  • IPEN-DOC 27062

    SORDI, GIAN M. . Comments on the General IAEA Safety Requirements - Part 3 - and suggestions for the next publications. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 298-303.

    Abstract: The international recommendations in question are described 52 requirements specified from chapter 2 to 5. The first chapter states that the number of fundamental safety principles has been increased form 3 to 10. To implement these requirments, the IAEA mentions 14 main parties but it is not clear which party is responsible for each of the fundamental safety principles. Chapter 2 presents 5 general requirements for protection and safety and makes it clear the responsibilities and competence of the government and regulatory body. ; but the responsibilities and competence of the other 12 principal parties reported in requeriment 4 are not clear. Chapter 3, which includes 37 requirements, is the most extensive and deals with planned exposure situations. Due to its extension, chapter 3 is left for a future paper, in case my comments are considered of some value by the principal parties involved. Chapter 4, with 4 requirements, deals with emergency exposure situations; and in chapter 5, the 6 requirements are about existing exposure situations. As to the requirements exposed in chapters 1, 2, 4 and 5 I have verified that the responsibilities and competence of the government and the regulatory body are clearly specified, which is not true for the other 12 principal parties. It is concerning this specific matter that I have made comments and suggestions. I also discuss the matters that are not under the responsibility of the radiological protection services but of other parties. Could the radiation protection service as a whole or in part be delegated to others, including the attributions of registrants or licensees?

    Palavras-Chave: recommendations; radiation protection; reporting requirements; safety reports

    Como referenciar este item
    Icon

  • IPEN-DOC 23678

    LEVY, DENISE S. ; SORDI, GIAN M.A.A. ; RODRIGUES, DEMERVAL L. ; CARNEIRO, JANETE C.G. . Enhancing communication on Radiological Protection throughout Brazil. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 284-290.

    Abstract: This paper focus on the potential value of Information and Communication Technologies (ICTs) to enhance communication on Radiological Protection throughout Brazil. The servers processing power added to the technology of relational databases allow to integrate information from different sources, enabling complex queries with reduced response time. It is our objective to provide radioactive facilities a complete repository for research, consultation and information on radiological protection in an integrated and efficient way. This webbased project works informatization of Radiological Protection Programs according to the positive tree published by AIEA in its Safety Series No. 102, the most generic and complete tree for an appropriate and effective radiation protection program. Up to this moment, the website counts on concepts, definitions and theory about optimization and monitoring procedures, interrelating information, currently scattered in various publications, in order to meet both Brazilian and international recommendations. The project involves not only the collection and interrelationship of existing information in the several publications, but also new approaches from some recommendations, such as potential exposures. Only few publications develop expressively the issue and, even though they provide fundamental theory, there is still lack of knowledge of failure probabilities, which currently constitutes a broad research field in radiological protection. This research proposes the development of fault trees and the analysis of different scenarios, suggesting paths to quantify probabilistically the occurrence of potential exposures, as well as probabilities to reach a certain level of dose. It is our target to complete the system in a near future, including other relevant issues, such as safe transport of radioactive materials, emergency response, radioactive waste management and decommissioning, among others. We believe the use of information technology for the radiological protection programs shall contribute greatly to provide information to Brazilian radioactive facilities throughout the country, spreading information to as many people as possible, minimizing geographic distances and stimulating communication and development.

    Palavras-Chave: radiation protection; communications; computer codes; nuclear facilities; information dissemination; radiation protection; alara

    Como referenciar este item
    Icon

  • IPEN-DOC 27060

    SAHYUN, ADELIA ; GHOBRIL, CARLOS N.; PEREZ, CLARICE F.; SORDI, GIAN M. . Some suggestions to adequate the IAEA Safety Standards Series No. 49 according to the General Safety Requirements Part 3 from IAEA. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 224-227.

    Abstract: At that time of publication SSR49 two exposure situations were considered, namely: practices and interventions, with Naturally Occuring Radioactive Material (NORM) being considered as intervention exposures but acknowledging that some natural sources can have exposures resulting from practices. In the Ba sic Safety Standards (BSS) the exposure situations have been categorised as planned, emergency and existing. These three situations necessitate an update of SSR No.49 since NORM fits in the existing situation, i.e one in which the doses already exist and should be reduced. To reduce the doses will create radioactive waste that must be either treated or stored. This scenario raises a problem of defining the dividing line between existing and planned situations. The point of transistion from one situation to the other needs to be clarified in order to establish the necessary controls for an existing situation whilst providing the necessary controls needed for the planned situation. For the latter planned situation several questions arise as to whether certain requirements can be exempted and under what circumstances. This paper will examine what the authors consider most important in more detail with some suggestions made for further consideration.

    Palavras-Chave: radioactive materials; natural occurrence; mining

    Como referenciar este item
    Icon

  • IPEN-DOC 27050

    ARAUJO, ELAINE C. ; ANDRADE, IZABEL da S. ; MACEDO, FERNANDA de M. ; CORREA, THAIS ; SALANI, MARIA H.G. de A. ; COSTA, RENATA F. da; RAMOS, SERGIANA dos P.; MARQUES, MARCIA T.A. ; LOPES, DANIEL S.; GUARDANI, MARIA L.G.; LANDULFO, EDUARDO ; GUARDANI, ROBERTO. Correlation study between air quality data and the Lidar system in Cubatao, Sao Paulo. In: SANTOS, JANE M. (Ed.); ANDRADE, MARIA de F. (Ed.); ALBUQUERQUE, TACIANA T.A. (Ed.) COMMUNITY MODELING AND ANALYSIS SYSTEM SOUTH AMERICA CONFERENCE, 3rd; AIR QUALITY CONFERENCE BRAZIL, August 28-31, 2017, Vitória, ES. Proceedings... Vitória, ES: Fundação Espírito-santense de Tecnologia, 2017. p. 175-177.

    Abstract: We present here the results of two methods with a scanning multiwavelength elastic lidar system and Beta Ray method (CETESB) realized in an industrial area. The objective is a comparer of these two methods to identify fixed sources of aerosol and to monitor plume dispersion. The results of the two aligned techniques indicate that can provide information on the concentration, spatial and temporal distribution of aerosol.

    Palavras-Chave: optical radar; remote sensing; pollutants; aerosols; air quality

    Como referenciar este item
    Icon

  • IPEN-DOC 27009

    SANTOS, I.P. ; LEVY, D.S. . Produção de energia elétrica a partir de fontes nucleares: uma abordagem para estudantes do ensino médio. In: SIMPOSIO INTERNACIONAL SOBRE EDUCACIÓN, CAPACITACIÓN Y GESTIÓN DEL CONOCIMIENTO EN ENERGÍA NUCLEAR Y SUS APLICACIONES, November 22-26, 2015, Cusco, Peru. Proceedings... 2015.

    Abstract: This study reports a pedagogical experiment in high school classes, in a private school in São Paulo. The purpose of this experiment was to put students in touch with topics related to electric power generation from radioactive sources This project was developed with emphasis on the content available in an educational online portal, the site www.radioatividades.com.br. The site has been created in order to disseminate knowledge to children, adolescents, parents and teachers about the peaceful use of nuclear energy. The portal content is free to access and use for educational purposes. The project had three stages: initial dynamics on the subject with students, working with research groups, conducting short courses in the portal "radioatividades" and a final evaluation, which consisted in seminars prepared by students themselves. The first stage aimed to verify the previous knowledge that students had on nuclear energy, raising common prejudices that usually appear. The second phase of the project aimed to demystify some concepts, such as the insecurity linked to the use of atomic energy. For this research there were used reliable sources, as the site of the National Nuclear Energy Commission (CNEN), Institute of Radiation Protection and Dosimetry (IRD) and International Atomic Energy Agency (IAEA), as well as short courses offered by the portal "Radioatividades". To finish the project, the students formed groups and presented seminars for their classmates, with split topics, illustrative slides and post presentation time to answer questions. There were highly satisfactory results at the end of the project, performances with good theoretical foundation and valuable clarifications on nuclear energy.

    Palavras-Chave: electric power; power generation; education; educational tools; adolescents; nuclear energy; training

    Como referenciar este item
    Icon

  • IPEN-DOC 27006

    GOULART, F. ; ICHIKAWA, R.U. ; TURRILLAS, X.; MARTINEZ, L.G. . Study on the microstructure of UNS S32304 duplex steel submitted to heat-treatments. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 45-48. DOI: 10.5151/phypro-viii-efa-12

    Abstract: Duplex stainless steels are characterized by a good combination of mechanical properties and corrosion resistance. Due to the metastable equilibrium between the ferritic (α) and austenitic (γ) phases, significant changes in the microstructure of these steels may occur when subjected to temperatures higher than the ambient, degrading their properties. In this work, it was investigated the influence of heat treatments on the microstructure and mechanical properties of a duplex stainless steel UNS-S32304. The heat-treatments were performed at four temperatures (300°C, 600°C, 900°C and 1000°C) with two treatment times (1 h and 6 h) and two processes of cooling down (in air and water). The samples were studied by X-ray diffraction using Pawley method to determine the lattice parameters, mean crystallite sizes and microstrain for the two phases and compared to Vickers microhardness results.

    Palavras-Chave: microstructure; stainless steels; microhardness; vickers hardness

    Como referenciar este item
    Icon

  • IPEN-DOC 27005

    REIS, L.A.M. ; ALENCAR, M. ; GOMES, M.P. ; PEREIRA, L.A.T. ; MUCSI, C.S. ; ROSSI, J.L. . Study of recycling process viability of zirconium alloys chips for melting in VAR furnace. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 65-67. DOI: 10.5151/phypro-viii-efa-16

    Abstract: Cavacos de ligas de zircônio (M5, Zirlo, Zircaloy) são gerados em elevadas quantidades na confecção de tubos e tampões das varetas que compõem o elemento combustível de reatores de potência refrigerados a água pressurizada (PWR). Essas são ligas importadas e por isso é mostrado interesse pela indústria de reciclagem na sua reutilização. Este trabalho apresenta os estudos de um processo de reciclagem e a obtenção de eletrodos prensados para serem fundidos em um forno VAR (Vacuum Arc Remelting). O processo se inicia com uma separação magnética, lavagem do fluido de corte que é solúvel em água, utilização de um desengraxante industrial, seguido por um enxágue com fluxo contínuo de água em alta pressão e secagem por fluxo de ar quente. Para a obtenção de eletrodos, os cavacos foram prensados em uma matriz de seção quadrada 40x40 mm² com 500 mm de comprimento, resultando num eletrodo com 20% da densidade aparente da liga. A fusão foi feita um forno VAR de laboratório no CCTM-IPEN, gerando um lingote maciço de 0,8 kg. A fusão dos cavacos é possível e viável em um forno VAR o que reduz em até 40 vezes o volume de armazenamento desse material.

    Palavras-Chave: zirconium alloys; recycling; vacuum melting

    Como referenciar este item
    Icon

  • IPEN-DOC 27004

    ABBADE, L. ; LARA, J.A.C. ; COUTO, C.P. ; GONSALEZ, B. ; COLOSIO, M.A.; ROSSI, J.L. . Resistance spot welding characterization of press hardened steel. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 10-13. DOI: 10.5151/phypro-viii-efa-03

    Abstract: In the automotive industry the resistance spot welding (RSW) is one of the most used processes for joining steel sheets, being of fundamental importance the quality assurance of this process. In this work, 22MnB5 steel sheets for the hot stamping process, also known as PHS (Press Hardening Steel), were joined by the technique of resistance spot welding, so that the welding parameters were changed 16 times for the evaluation of the influence of these parameters on the mechanical properties. By conducting ultrasonic, tensile and hardness test, followed by metallography, it was possible to identify the characteristics of the spot weld effect on the material. The results of the tests performed in this work confirmed the difference in mechanical strength of the thermal zone (ZTA) in relation to the molten zone (ZF). For a certain set of the parameters it was shown a decrease in the strength of the ZTA and increasing to the weld point, which is demonstrated in the microstructural analysis and thus justifies the detachment of the weld button of the base material during tensile testing, i.e., there was a higher strength in the welded area.

    Palavras-Chave: resistance welding; spot welding; steels; hardening

    Como referenciar este item
    Icon

  • IPEN-DOC 27003

    NASCIMENTO, J.O. do; PEREIRA, H.B.B.; MORET, M.A.; BARBOSA, L.P. ; TAKIISHI, H. . Redes semânticas em Ciências dos Materiais: uma aplicação da Teoria de Redes. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 116-121. DOI: 10.5151/phypro-viii-efa-27

    Abstract: Uma possibilidade de estudos em sistemas complexos corresponde a utilização da Teoria de redes sociais e complexas. Este artigo tem como objetivo descrever e analisar as redes semânticas baseadas nas palavras-chave dos artigos publicados nos anais do Congresso Brasileiro de Engenharia e Ciências dos Materiais (CBECiMat) referente ao ano de 2010. Alicerçamo-nos nas métricas de estatística básica pertencente às redes complexas, ao índice de centralidade de grau pertencente as redes sociais e apresentamos o método de construção das redes semânticas. As análises indicaram quais as palavras-chave se destacaram (por meio do número de suas conexões) e as topologias verificadas, sugerem redes livre de escala e mundo pequeno. Estes resultados auxiliam na escolha e observância de palavras-chave em futuros trabalhos nas áreas de ciências dos materiais e do evento (materiais cerâmicos, materiais compósitos, materiais metálicos, materiais poliméricos e ensino de materiais), bem como arguir sobre estratégias em mecanismos de busca de trabalhos científicos, tendo como descritores as palavras-chave.

    Palavras-Chave: network analysis; information systems; neural networks; materials

    Como referenciar este item
    Icon

  • IPEN-DOC 27002

    GOMES, M.P. ; SANTOS, I.P. ; COUTO, C.P. ; BETINI, E.G. ; COLOSIO, M.A.; ROSSI, J.L. . Microstructural characterization of air quenched valve seat inserts obtained with AISI D2 tool steel. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 42-44. DOI: 10.5151/phypro-viii-efa-11

    Abstract: The obtention of valve seat insert (VSI) by powder metallurgy using a mixture of iron powder and tool steel is fulfilling the requirements for substitution of cobalt and lead in commercial parts, aiming cost reduction and avoid the lead toxicity. The aim of this work consisted of evaluate the influence of heat treatment on VSI obtained with AISI D2 tool steel powder. The AISI D2 tool steel powder was mixed with iron powder and additives such as manganese sulphide, zinc stearate, graphite and carbides. The heat treatment of the VSI consisted of air quenching followed by double tempering it at 500 °C. The microstructural characterization was performed using scanning electron microscopy and energy dispersive spectroscopy.

    Palavras-Chave: powder metallurgy; air; quenching; valves; steels; tools

    Como referenciar este item
    Icon

  • IPEN-DOC 27001

    GOMES, M.P. ; SANTOS, I.P. ; REIS, L.A.M. ; CIONE, F.C. ; COLOSIO, M.A.; ROSSI, J.L. . Influence of air quenching on apparent hardness of valve seat inserts obtained with AISI M2 high-speed steel powder. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 39-41. DOI: 10.5151/phypro-viii-efa-10

    Abstract: The aim of this work consisted of evaluate the influence of heat treatment on sintered valve seat inserts (VSI) obtained with the AISI M2 high-speed steel powder. The AISI M2 high-speed steel powder was mixed with iron powder and additives such as manganese sulphide, zinc stearate, graphite and carbides. The heat treatment of the VSI consisted of air quenching followed by double tempering it in seven different equidistant temperatures, from 100 °C until 700 °C. The mechanical property was measured regarding the VSI apparent hardness. The results indicated that the VSI obtained with the AISI M2 high-speed steel powders mixtures showed the best results regarding its apparent hardness after air quenching and double tempering it at 600 °C.

    Palavras-Chave: powder metallurgy; air; quenching; valves; steels

    Como referenciar este item
    Icon

  • IPEN-DOC 27000

    BETINI, E.G. ; GOMES, M.P. ; REIS, L.A. ; MUCSI, C.S. ; ALENCAR, M.C. ; ORLANDO, M.T.D.; LUZ, T.S.; AVETTAND-FENOEL, M-N.; ROSSI, J.L. . Effect of the cooling rates on heat-affected zone of UNS S32304 duplex stainless steel welded by pulsed GTAW process. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 14-18. DOI: 10.5151/phypro-viii-efa-04

    Abstract: Two thin plates of UNS 32304 of duplex stainless steel were joined by pulsed gas tungsten arc welding (GTAW) using a mixture 98% of argon plus 2% of nitrogen as shielding gas or pure argon as purging gas at the bottom of the plate without filler metal. The temperature profile close and away from the weld pool was measured using K type (Ni-Cr) thermocouples, connected to a digital data acquisition system. The thermal cycles was recorded in the heat-affected zone (HAZ) at a distance in between 1 and 3 mm from the joint line. The cooling rate and holding time were studied with respect to the used purging gas. Experimental thermal profiles are in good agreement with literature values. The joints welded without any purging gas revealed high peak temperature and cooling rates. The present investigation showed that temperature peaks are comprised in the phase transformation temperature ranges for the welded duplex stainless steel.

    Palavras-Chave: gas tungsten-arc welding; stainless steels; cooling; thermal cycling

    Como referenciar este item
    Icon

  • IPEN-DOC 26999

    PASCOATO, R. ; ARANHA, L.C. ; MUCSI, C.S. ; ROSSI, J.L. . Desenvolvimento de um torquimetro para medição dinâmica de microtorque. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 62-64. DOI: 10.5151/phypro-viii-efa-15

    Abstract: Foi desenvolvido um dispositivo protótipo de um torquímetro para ensaio de medição dinâmica de micro torques. Este dispositivo foi usado para a avaliação de implantes ortodônticos. O ensaio consistiu na inserção e retirada de pilares protéticos em implantes odontológicos, com torques menores que 100 Ncm. O principal componente desse protótipo foi a barra de torque, nesta, foi aplicado um extensômetro tipo strain gage. As deformações sofridas por este componente, não descriminavam entre deformações devido a tensões de flexão e tensões de torção. Com o propósito de diminuir esta sensibilidade a deformação por flexão e aumentar a sensibilidade da torção, foi proposta uma nova geometria para a barra de torque. Após ser estudada analiticamente, esta nova geometria mostrou- se bastante favorável quanto ao aumento da sensibilidade à torção do componente e a diminuição da interferência devido ao seu peso próprio.

    Palavras-Chave: dentistry; implants; surgical materials; medical supplies; extensometers; torque; stability

    Como referenciar este item
    Icon

  • IPEN-DOC 26998

    SOUZA, A.C.; SILVA, A.C.; ROSSI, J.L. ; CIONE, F.C. . Analysis thermogravimetric of tungsten composite for gama radiaction shielding. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 36-38. DOI: 10.5151/phypro-viii-efa-09

    Abstract: The generation of Mo-99mTc generators for hospitals requires the transport of the Mo-99m material in containers with physicochemical properties for especially the shielding of gamma radiation [4, 5]. The application of tungsten alloys has been developed with the objective of minimizing the effects of radiation, being used in the manufacture of devices for the transport of radioactive material, considering its properties of specific mass (60% dense than lead), resistance corrosion, excellent absorption of high energy radiation and high mechanical strength [16,17]. The kraft lignin, a natural polymer obtained from the Kraft process of cellulosic pulp extraction, considered a residue of the cellulosic industry, can be used as a high adhesive material. The objective of this work was to perform the Thermogravimetric (TG), Differential Exploration Calorimetry (DSC) and X-ray diffraction (XRD) analyses of a new composite of tungsten and kraft lignin. The results showed the thermal and crystallographic properties of the composite, which could contribute to obtain a new material with ability to attenuate gamma radiation.

    Palavras-Chave: composite materials; tungsten; thermal gravimetric analysis; molybdenum 99

    Como referenciar este item
    Icon

  • IPEN-DOC 26997

    SOUZA, A.C.; ROSSI, J.L. ; FERNANDES, H.B.; GOUVEA, A.F.G.. Analysis of the microstructural evolution of composite of Tungsten with lignin kraft. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 76-78. DOI: 10.5151/phypro-viii-efa-19

    Abstract: In materials science and engineering, there is a demand in new materials for radiation shielding in the transport of radiopharmaceuticals used in the diagnosis and therapy of cancer, justifying the interest in developing this work. The obtained lignin kraft and tungsten form the precursors used for metal-organic composite. Tungsten metal has diverse applications in the nuclear sector presents an enormous mechanical strength and an excellent cross section with thermal neutrons. The aim of this study is to analyse the microstructural evolution of metal-organic composite using the kraft lignin and tungsten, using analysis of scanning electron microscopy (SEM), microhardness test and x-ray diffraction (XRD). Microscopic analysis showed the granulometry of the precursors separate and composite morphology, observing the formation of alpha (α) and beta (β) phases and absence of oxidation process for different heat treatment temperatures. The spectra of x-ray diffraction identified the structures of each phase formed and micro hardness measures showed an increase of mechanical resistance with temperature. The results of the microstructural characterization of metal-organic composite, will contribute in the next steps of attenuation measurements of gamma radiation.

    Palavras-Chave: composite materials; tungsten; lignin; microstructure

    Como referenciar este item
    Icon

  • IPEN-DOC 26996

    COSTA, P.D.O.L. ; COSTA, I. ; COUTO, C.P. ; ROSSI, J.L. . Análise gravimétrica do revestimento de zinco-níquel de um aço 22MNB5 e zinco puro. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 29-31. DOI: 10.5151/phypro-viii-efa-07

    Abstract: O aço de alta resistência 22MnB5 é utilizado com revestimento de alumínio-silício com o objetivo de melhorar a resistência a corrosão e desgaste em peças expostas em meios molhados que favorecem o fenômeno corrosivo. Sua principal aplicação é no setor automobilístico englobando peças que integram a estrutura principal do veículo. Uma alternativa para a substituição do revestimento alumínio-silício é uma composição química do revestimento utilizando zinco-níquel. Neste trabalho foi estudado a evolução do processo de perda de massa em diferentes meios corrosivos (ácido, neutro e alcalino) identificando o comportamento do material revestido do aço 22MnB5 e comparando com zinco puro. Foram utilizados três variáveis: revestimento zinco-níquel como recebido, revestimento zinco-níquel estampado e zinco puro. Foi constatado que em meios ácidos (pH de 0 a 1) o processo de corrosão foi muito intenso para todos os materiais, do pH 3 ao pH 13 a perda de massa foi insignificante, mesmo sendo imersa durante dias, havendo a proteção do material pela camada passiva formada de óxido. O revestimento estampado se mostrou com maior tendência a perda de massa, por possuir mais defeitos em sua superfície facilitando o processo corrosivo enquanto que o revestimento como recebido se mostrou bem resistente.

    Palavras-Chave: nickel; zinc; silicon; aluminium; steels; gravimetric analysis; surface coating; mass loss

    Como referenciar este item
    Icon

  • IPEN-DOC 26995

    RAMANATHAN, L.V. ; FERNANDES, S.M.C. ; CORREA, O.V. ; SOUZA, J.A. de ; ANTUNES, R.A.; OLIVEIRA, M.C.L. de. Coatings for safe long term wet storage of spent Al-clad research reactor fuels. In: INTERNATIONAL CONFERENCE ON RESEARCH REACTORS: SAFE MANAGEMENT AND EFFECTIVE UTILIZATION, November 16-20, 2015, Vienna, Austria. Proceedings... Vienna, Austria: International Atomic Energy Agency, 2015. p. 1-8.

    Abstract: Pitting corrosion of the aluminium cladding of spent research reactor (RR) fuels in wet storage has been observed and the use of conversion coatings to protect the cladding was proposed. A coating prepared by conventional chemical processing as opposed to electrochemical processing is the only option due to constraints related to the shape of the fuel and its high radioactivity. Hence, hydrotalcite (HTC) and boehmite were considered. This paper presents: (a) preparation of hydrotalcite (HTC) coatings from different baths followed by post-coating treatments; (b) corrosion behavior of HTC coated AA 6061 alloy; (c) results of field studies in which uncoated and HTC coated AA 6061 alloy coupons and plates, the latter assembled as a dummy fuel element, were exposed to the IEA-R1 reactor spent fuel basin for extended periods. The laboratory and field tests revealed marked improvements in the corrosion resistance of HTC coated specimens, coupons and plates. The mechanism of corrosion protection is presented.

    Palavras-Chave: cladding; coatings; corrosion protection; corrosion resistance; iear-1 reactor; pitting corrosion; spent fuels; wet storage

    Como referenciar este item
    Icon

  • IPEN-DOC 26994

    GOMES, M.P.; SANTANA, M.S.; ROSSI, J.L. ; POLITANO, R. . Estudo da energia mecânica necessária para a geração de pulsos mecânicos em uma barra de Kolsky. In: CONGRESSO CIENTÍFICO DA SEMANA NACIONAL DE CIÊNCIA E TECNOLOGIA NO IFSP, 6., 20-23 de outubro, 2015, Bragança Paulista, SP. Anais... Bragança Paulista, SP: Instituto Federal de São Paulo - Bragança Paulista, 2015.

    Abstract: A análise da resposta a pulsos mecânicos em materiais a serem utilizados em sistemas para transporte de substâncias radioativas é uma das condições para a sua respectiva seleção e dimensionamento. Para que se faça a caracterização da resposta dos materiais candidatos a este tipo de solicitação é necessária a construção de aparatos experimentais, sendo que neles é aplicado um pulso mecânico de forma controlada e com parâmetros conhecidos, possibilitando assim a obtenção das características mecânicas do corpo-de-provas - aparato este conhecido como barra de Kolsky. Uma parte crítica do aparato, é o alinhamento de todo o conjunto, pois o ensaio a ser realizado é considerado unidimensional. O menor desalinhamento irá causar distorções na onda mecânica de compressão, então os dados obtidos pela extensometria na superfície das barras não serão condizentes com a realidade. Portanto, o propósito deste projeto foi o de produzir um mancal que possibilitasse o alinhamento com uma maior precisão dos eixos x, y do aparato. Tal alinhamento será inicialmente feito manualmente, porém no dimensionamento e concepção do mancal foi reservado um espaço para o acoplamento de um servomotor, que futuramente irá ser utilizado para o ajuste preciso e automático do aparato.

    Palavras-Chave: pulse generators; mechanical efficiency; mechanical properties; compression; bearings; radioactive materials

    Como referenciar este item
    Icon

  • IPEN-DOC 26992

    FERREIRA, ALLANA C.P.; SANTOS, ELINALDO N. dos; MESQUITA, ARIMATEA P. de P.; ARAUJO, EDVAL G. de; GONZALEZ, CEZAR H.; AMBROZIO FILHO, FRANCISCO ; ARAUJO FILHO, OSCAR O. de. Endurecimento secundário do aço rápido AISI M3:2 nome comercial Sinter 23 produzido por uma técnica de metalurgia do pó / Secondary hardening of an AISI M3:2 high speed steel named Sinter 23 produced through powder metallurgy techniques. In: ABM WEEK; CONGRESSO ANUAL DA ABM, 70.; ENCONTRO NACIONAL DE ESTUDANTES DE ENGENHARIA METALÚRGICA, DE MATERIAIS E DE MINAS,15., 17-21 de agosto, 2015, Rio de Janeiro, RJ. Proceedings... São Paulo, SP: Blucher Proceedings, 2015. p. 1755-1762.

    Abstract: O endurecimento secundário de aço rápido AISI M3:2 nome comercial Sinter 23 obtido por uma técnica de metalurgia do pó de sinterização por compactação isostática a quente é objeto desse trabalho de pesquisa. O aço rápido em questão foi austenitizado em banho de sal a 1.140°C, 1.160°C, 1.180°C e 1.200C, temperado ao ar e revenimento a 540°C, 560°C e 580C. Amostras do aço rápido foram fabricadas e submetidas ao tratamento térmico acima descrito e submetida a ensaios de dureza Vickers e Rockwell C para a determinação das suas respostas ao tratamento térmico de endurecimento e avaliação do pico de endurecimento secundário através dos resultados de dureza.

    Palavras-Chave: steels; hardening; sintering; rockwell hardness; vickers hardness

    Como referenciar este item
    Icon

  • IPEN-DOC 26991

    DEL BUSSO, NICOLANGELO; MONTEIRO, WALDEMAR A. . Caracterização microestrutural e mecânica de aço API-5L-X70 após soldagem pelo método de arco submerso / Mechanical and microstructural characterization in API 5L X70 steel after submerged arc welding process. In: ABM WEEK; CONGRESSO ANUAL DA ABM, 70.; ENCONTRO NACIONAL DE ESTUDANTES DE ENGENHARIA METALÚRGICA, DE MATERIAIS E DE MINAS,15., 17-21 de agosto, 2015, Rio de Janeiro, RJ. Proceedings... São Paulo, SP: Blucher Proceedings, 2015. p. 1665-1674.

    Abstract: A soldagem é um processo industrial empregado na indústria do petróleo e em minerodutos devido ao sua excelente resistência mecânica. Os seus parâmetros provocam alterações metalúrgicas significativas no metal de solda. Neste trabalho foi estudado o aço microligado da classe API-5L-X70 em termos de microestrutura (metalografia e fratografia por microscopia óptica e eletrônica) e propriedades mecânicas (ensaio de tração a temperatura ambiente, dureza, dobramento e ensaio de impacto Charpy a – 20o C e a 0o C) após soldagem em arco submerso, nas regiões da zona fundida (ZF), zona termicamente afetada (ZTA) e metal de base (MB). O exame metalográfico apresentou microestrutura bandeada consistindo de ferrita poligonal, perlita e bainita, com pequeno tamanho de grão. Os resultados mostram o aumento da resistência mecânica influenciada pela presença de ferrita acicular. Análise fratografica apos ensaios mecânicos revelam comportamento dúctilfrágil.

    Palavras-Chave: submerged arc welding; microstructure; mechanical properties; fractography

    Como referenciar este item
    Icon

  • IPEN-DOC 26988

    GUERRERO-RASCADO, J.L.; ALADOS-ARBOLEDAS, L.; BENAVENT-OLTRA, J.A.; CAZORLA, A.; CHAMIZO, S.; FOYO, I.; GRANADOS-MUNOZ, M.J.; KOWALSKI, A.S.; OLMO, F.J.; PEREZ-RAMIREZ, D.; SERRANO-ORTIZ, P.; TITOS, G.; CASQUERO-VERA, J.A.; ORTIZ-AMEZCUA, P.; COSTA, M.J.; LOPES, F.J.S. ; LYAMANI, H.; PEREZ-PRIEGO, O.; PREISSLER, J.; MARTIN-TRIGO, O.. E-learning in the teaching-learning process at postgraduate level: application to geomet subjects. In: GOMEZ CHOVA, L. (Ed.); LOPEZ MARTINEZ, A. (Ed.); CANDEL TORRES, I. (Ed.) INTERNATIONAL CONFERENCE ON EDUCATION AND NEW LEARNING TECHNOLOGIES, 9th, July 3-5, 2017, Barcelona, Spain. Proceedings... Valencia, Spain: IATED Academy, 2017. p. 2699-2704. DOI: 10.21125/edulearn.2017.1561

    Abstract: This teaching innovation project arises from experience previously gained with other innovation projects encompassing several degrees with the aim of improving the academic performance of the students and the quality of teaching in several subjects of the Master’s program in Geophysics and Meteorology (GEOMET) at the University of Granada (Spain). Among other novelties, through this project resources have been developed for students to carry out an online self-assessment of their knowledge regarding contents of the different subjects through the Moodle platform, checking the level of skills acquired. In addition, the project includes a system of exchange of teaching, electronic resources between teachers and students (guides of subjects, viewgraphs, practical documents, among others). This platform has increased the coordination between the lecturers who teach the subjects.

    Palavras-Chave: e-learning; training; meteorology; computer codes

    Como referenciar este item
    Icon

  • IPEN-DOC 26987

    MOREIRA, TATIANA M. ; SEO, EMILIA S.M. . Caracterização e utilização das fibras da casca da laranja como biossorvente na recuperação de corpos hídricos contaminados por derramamento de derivados do petróleo. In: CONGRESSO DA ASSOCIAÇÃO BRASILEIRA DE ENGENHARIA SANITÁRIA E AMBIENTAL; FEIRA NACIONAL DE SANEAMENTO E MEIO AMBIENTE, 2-6 de outubro, 2017, São Paulo, SP. Proceedings... Rio de Janeiro, RJ: Associação Brasileira de Engenharia Sanitária e Ambiental, 2017. p. 1-10.

    Abstract: Com base no desenvolvimento sustentável, este trabalho, visou buscar materiais tecnológicos com enfoque na reciclagem, onde se destacam as fibras vegetais, como as da laranja, que possuem baixo custo e impacto ao meio ambiente, com boa eficiência quando utilizadas para o processo de biossorção. Este método vem sendo utilizado como um recurso para redução de problemas ambientais causados por contaminação em corpos hídricos, como córregos e rios urbanos, por derramamento de substâncias tóxicas, minimizando assim os impactos dos ecossistemas aquáticos, bem como a contaminação do solo. A preparação destas fibras foi feita por meio de tratamentos físicos e químicos, tais como: lavagem, secagem, moagem, mercerização (tratamento químico com agente alcalino que ataca a superfície da fibra, melhorando suas características de sorção), classificação granulométrica e caracterização. Esses procedimentos geraram um material que pôde ser empregado como um biossorvente. Como contaminantes, foram utilizados derivados do petróleo, tais como a gasolina e o óleo diesel. Na caracterização foram utilizadas técnicas de: Picnometria, Termogravimetria, Análise Elementar, Microscopia Eletrônica, Fluorescência de Raios X, Teor de Umidade e Cinzas, Retenção de água, Hidrofobicidade e Flutuabilidade. Para os ensaios práticos foram mensuradas a sorção de contaminantes tanto em sistema seco, onde os contaminantes estão em contato direto com os biossorventes, quanto aquoso, simulando um derramamento de óleo diesel e gasolina em um corpo hídrico. Os resultados demonstraram que o biossorvente testado possui boa capacidade sortiva nos dois sistemas testados. Portanto, dada a sua origem renovável e de baixo custo, este material se mostrou eficiente para a finalidade proposta.

    Palavras-Chave: bioadsorbents; water resources; fibers; fruits; oranges

    Como referenciar este item
    Icon

  • IPEN-DOC 26986

    MILAGRE, MARIANA X. ; MACHADO, CARULINE S.C. ; ARAUJO, JOAO V. ; ASTARITA, ANTONELLO; PEBERE, NADINE; VIVIER, VINCENT; COSTA, ISOLDA . Intergranular corrosion susceptibility of Al-Cu-Li alloys. In: EUROPEAN CORROSION CONGRESS; INTERNATIONAL CORROSION CONGRESS, 20th; PROCESS SAFETY CONGRESS, September 3-7, 2017, Prague, Czech Republic. Proceedings... Frankfurt, Germany: European Federation of Corrosion, 2017.

    Abstract: In the present study, the intergranular corrosion (IGC) susceptibility of commercial Al-Cu-Li alloys of the third generation (AA2098-T351, AA2198-T3 and AA2198-T851) was compared with that of the AA2024-T3 alloy according to ASTM G110 test. In addition, anodic and cathodic polarization curves were carried out in the ASTM G110 test solution at room temperature. The cross-section of the samples after the ASTM G110 test was observed by scanning electron microscopy (SEM) to evaluate the extension of the corrosion attack. The susceptibility to intergranular attack of the tested alloys was ranked according to the attack by IGC and from the anodic and cathodic polarization curves. The results showed that the AA2024-T3 and the AA2198-T3 alloys presented higher susceptibility to intergranular corrosion comparatively to the other alloys tested (AA2098-T351 and AA2198-T851). The AA2098-T351 alloy was associated to the highest resistance to intergranular attack among the alloys evaluated. A correlation was seemingly established between the stress relief treatment of the alloy and its corresponding susceptibility to intergranular or intragranular corrosion.

    Palavras-Chave: intergranular corrosion; aluminium alloys; lithium alloys; polarization

    Como referenciar este item
    Icon

  • IPEN-DOC 26984

    ABREU, C.P. ; MELO, H.G. de; PEBERE, N.; MOGILI, N.V.V.; COSTA, I. ; VIVIER, V.. Corrosion resistance evaluation of the different zones on the AA2024-T3 and AA7475-T651 alloys welded by FSW. In: EUROPEAN CORROSION CONGRESS; INTERNATIONAL CORROSION CONGRESS, 20th; PROCESS SAFETY CONGRESS, September 3-7, 2017, Prague, Czech Republic. Proceedings... Frankfurt, Germany: European Federation of Corrosion, 2017. p. 1-14.

    Abstract: The aeronautic industry has a great interest in joining dissimilar aluminium alloys used in different parts of an aircraft. The Friction Stir Welding (FSW) process has been considered an effective alternative to conventional techniques for the welding of high strength alumin-ium alloys. However, this procedure results in zones with different microstructures due to thermal and thermomechanical effects involved during the joining process, leading to the formation of the thermomechanically affected zone (TMAZ), the heat affected zone (HAZ), the stir zone (nugget), and the unaffected base metal (BM). As the corrosion resistance of materials depends on their microstructures, the aim of this study was to investigate the intrin-sic corrosion resistance of the different zones of the AA2024-T3 and AA7475-T761 alloys welded by FSW, without considering the coupling effects between the different zones. This was achieved by evaluating the corrosion resistance of each individual zone in 0.1 M Na2SO4 + 1 mM NaCl solution by electrochemical techniques, such as open circuit potential meas-urements, polarization curves, and electrochemical impedance spectroscopy, using an elec-trochemical cell with an exposed area of 0.78 mm2. The electrochemical results showed that the lowest corrosion resistance was associated to the nugget zone, on which a galvanic cou-pling between the 2024 and 7475 alloys takes place. The corrosion resistance was also low-ered on the TMAZ of both alloys. This behaviour was associated to the enhanced precipita-tion of the η phase (MgZn2) at the grain boundaries in the 7475 alloy and to the coarsening of S phase (AlCuMg) precipitates in the 2024 alloy, both processes favoured by the thermome-chanical effects in these specific zones as demonstrated by TEM analysis.

    Palavras-Chave: aluminium alloys; corrosion resistance; friction; welding; microstructure

    Como referenciar este item
    Icon

  • IPEN-DOC 26982

    FERREIRA, E.G. ; MARUMO, J.T. ; VICENTE, R. ; LANGTON, C.A.; DUNCAN, A.J.; WILLIAMS, M.R.. Test methods for cementitious seal materials for borehole disposal. In: ANNUAL WASTE MANAGEMENT CONFERENCE, 43rd, March 5-9, 2017, Phoenix, Arizona, USA. Proceedings... Tempe, Arizona, USA: Waste Management Symposia, 2017. p. 1-13.

    Abstract: The Nuclear and Energy Research Institute (IPEN-CNEN/SP) in Sao Paulo-Brazil, is considering borehole disposal of disused sealed radioactive sources (DSRS), which were used in smoke detectors, lightning arrestors, radiotherapy, industrial gauges, irradiators, and other applications. The current IPEN concept of borehole is a modified BOSS system developed by the International Atomic Energy Agency (IAEA). It differs from the IAEA’s design in that the disposal zone is below 300 m, and the DSRS are placed directly in the disposal packages constituted of stainless steel containers with 1.5 L capacity. A borehole drilled through sediment and granite, stabilized with stainless steel casing and cement grout is proposed for the conceptual model. Standard cement-material test methods and performance specific test methods, including accelerated aging methods, are needed for modeling the performance of the candidate cementitious grouts. A cross-disciplinary team from the USA Savannah River National laboratory is providing technical assistance to IPEN in this performance assessment.

    Palavras-Chave: boreholes; cements; granites; radiation sources; radioactive waste disposal; stainless steels; underground disposal

    Como referenciar este item
    Icon

  • IPEN-DOC 26967

    SANTOS, VINICIUS T. dos; SANTOS, GIVANILDO A. dos; NAKAMOTO, FRANCISCO Y.; SILVA, MARCIO R. da; FRANCO, ANTONIO T.R.; COUTO, ANTONIO A. . Influência das variáveis térmicas de solidificação na microestrutura e dureza da liga bronze alumínio níquel CuAl10Ni5Fe5 / Influence of thermal variables of solidification on the microstructure and hardness of nickel aluminum bronze alloy CuAl10Ni5Fe5. In: CONGRESSO BRASILEIRO DE ENGENHARIA DE FABRICAÇÃO, 9., 26-29 de junho, 2017, Joinville, SC. Anais... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas, 2017.

    Abstract: O objetivo deste trabalho é obter correlações entre a microestrutura e dureza da liga Bronze Alumínio Níquel CuAl10Ni5Fe5 em função das variáveis térmicas de solidificação. Estas variáveis são responsáveis pela formação das fases e intermetálicos presentes no Bronze Alumínio Níquel, os quais interferem diretamente nas propriedades mecânicas do material. A liga CuAl10Ni5Fe5 foi solidificada em um dispositivo com sistema ascendente sob condições não-estacionárias de fluxo de calor. O calor foi extraído direcionalmente através de uma base de aço ABNT 1020 refrigerada a água. No que diz respeito à análise da microestrutura, utilizou-se microscopia eletrônica de varredura, permitindo a verificação das morfologias das fases e intermetálicos. As variáveis térmicas de solidificação geram resultados referentes à velocidade de deslocamento da isoterma liquidus e à taxa de resfriamento. A propriedade mecânica foi avaliada por meio de ensaio de dureza em toda extensão longitudinal da peça solidificada, a qual apresenta a formação das fases e intermetálicos formados por meio das condições de solidificação impostas pelo sistema metal/molde. A microestrutura e dureza são correlacionadas com as variáveis térmicas de solidificação, enfatizando a importância das taxas de resfriamento na formação das fases e intermetálicos da liga CuAl10Ni5Fe5. O resultado deste trabalho demonstra que, quanto maior a taxa de resfriamento, maior é o resultado obtido de dureza.

    Palavras-Chave: bronze; aluminium; nickel; solidification; hardness

    Como referenciar este item
    Icon

  • IPEN-DOC 26961

    SANTOS, CAMILA F.R.T.T. ; SILVA, TATIANE B. de S.C. da ; COTRIM, MARYCEL E.B. ; PIRES, MARIA A.F. . Fatores de emissão atmosférica e análise de significância aplicada na gestão da qualidade do ar no campus do IPEN/CNEN-SP / Atmospheric emission factors and significance analysis applied to the air quality management in the IPEN / CNEN-SP campus. In: ENCONTRO INTERNACIONAL SOBRE GESTÃO EMPRESARIAL E MEIO AMBIENTE, 18., 5-6 de dezembro, 2016, São Paulo, SP. Anais... São Paulo, SP: Faculdade de Economia, Administração e Contabilidade da Universidade de São Paulo - FEA USP, 2016.

    Abstract: Devido ao compromisso com a melhoria do meio ambiente, aliado às crescentes exigências dos órgãos ambientais, e a necessidade de identificar a contribuição de cada atividade/processo desenvolvido em institutos de pesquisas, quanto ao impacto destes à qualidade do ar, este trabalho tem a finalidade de desenvolver um modelo de inventário e aplicar uma metodologia de cálculo, que permita estimar a emissão de poluentes atmosféricos, decorrentes das atividades dos centros de pesquisa e desenvolvimento do Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP). O estudo foi motivado pela ausência de metodologias de cálculo de emissões atmosféricas específicas para fontes fixas como capelas de exaustão. Para a elaboração dos cálculos foram adotados os fatores de emissão e a equação descrita na AP-42 da EPAEnvironmental Protetion Agency. Foram utilizadas como abordagens de cálculo de emissões: a) Mensuração direta (por meio do inventário de emissões atmosféricas); e b) Estimativa de emissões (utilizando estimativa da taxa de emissão calculada a partir do fator de emissão apropriado). Como produto final obteve-se um inventário de emissões atmosféricas de fontes fixas da instituição e estimou-se a emissão atmosférica do Centro de Química e Meio Ambiente (CQMA) a fim de estabelecer de forma efetiva o Programa de Monitoramento e Controle de Emissões Atmosféricas (PMEA – IPEN), servindo de base para outras instituições de Pesquisa, Desenvolvimento & Inovação.

    Palavras-Chave: atmospheric circulation; emission; environment; pollution regulations; inventories

    Como referenciar este item
    Icon

  • IPEN-DOC 26954

    GONÇALES, LETICIA dos R.; FERRAZ, LUCAS C. de C.; CORREA, OLANDIR V. ; ANTUNES, RENATO A.. Estudo da influência do tamanho de grão sobre o comportamento de corrosão da liga de magnésio AZ91D / Study of grain size influence on the corrosion behavior of AZ91D magnesium alloy. In: ABM WEEK; CONGRESSO ANUAL DA ABM, 71.; ENCONTRO NACIONAL DE ESTUDANTES DE ENGENHARIA METALURGICA, DE MATERIAIS E DE MINAS, 16., 26-30 de setembro, 2016, Rio de Janeiro, RJ. Anais... São Paulo, SP: Associação Brasileira de Metalurgia, Materiais e Mineração, 2016. p. 1326-1334.

    Abstract: A liga AZ91D apresenta 9%pAl e 1%pZn e pode ser submetida a tratamento térmico de solubilização seguido de envelhecimento para melhoria de propriedades mecânicas por meio de precipitação da fase beta-Mg17Al12. Esta fase, porém, pode ter efeitos distintos sobre o comportamento de corrosão da liga. Buscando estudar a influência do tamanho de grão da matriz alfa e a presença de precipitados beta sobre a resistência à corrosão da liga AZ91D, este trabalho utilizou lingotes com estrutura bruta de fusão na obtenção de amostras solubilizadas, laminadas a frio e então envelhecidas, para subsequente análise microestrutural e do comportamento de corrosão. A solubilização ocorreu a 445ºC por 24h e foi efetiva em dissolver quase completamente a fase beta. A laminação levou a uma redução de 20% da espessura das amostras e de 400 para 130 μm o tamanho de grão médio, após envelhecimento. O envelhecimento feito a 200ºC em 2 e 24h permitiu a precipitação de fase beta em maior quantidade e melhor distribuição por contornos de grão em relação às amostras fundidas ou solubilizadas. Ensaios de imersão foram realizados, apontando uma leve queda na taxa média de corrosão quando se lamina a amostra, enquanto as amostras solubilizadas (sem fase beta) mostraram maior susceptibilidade à corrosão. Assim, é possível indicar que o refinamento de grãos é benéfico ao formar uma rede de proteção em ligas de magnésio AZ91D, apesar de introduzir defeitos gerados pela laminação.

    Palavras-Chave: magnesium alloys; corrosion resistant alloys; rolling; cold working

    Como referenciar este item
    Icon

  • IPEN-DOC 26953

    GOMES, MAURILIO P. ; SANTOS, IGOR P. dos ; REIS, LUIS A.M. dos ; COUTO, CAMILA P. ; MUCSI, CRISTIANO S. ; COLOSIO, MARCO A.; ROSSI, JESUALDO L. . Characterization of sintered valve seat inserts obtained with AISI M2 high-speed steel after air quenching / Caracterização de insertos para assentos de válvulas sinterizados obtidos com o aço rápido AISI M2 depois de temperados ao ar. In: ABM WEEK; CONGRESSO ANUAL DA ABM, 72.; ENCONTRO NACIONAL DE ESTUDANTES DE ENGENHARIA METALURGICA, DE MATERIAIS E DE MINAS, 17., 02-06 de outubro, 2017, São Paulo, SP. Anais... São Paulo, SP: Associação Brasileira de Metalurgia, Materiais e Mineração, 2017. p. 993-1000.

    Abstract: The aim of this work was to heat treat and characterize sintered valve seat inserts (VSI). The powder metallurgy route was the only way found to substitute cobalt and lead, used in the VSI original alloy, due to their high cost and toxicological effect, respectively. The studied VSI was obtained with AISI M2 high-speed steel powder mixed with iron powder and other additives such as manganese sulphide, graphite, zinc stearate, carbides and copper, which was added by metallic infiltration. All the VSI were air quenched and double tempered, for one hour each, at seven different equidistantly temperatures, ranging from 100 °C up to 700 °C. The physical and mechanical properties were evaluated by means of the VSI apparent density, apparent hardness and crush radial strength. The chemical composition was determined through gas analysis, for the light elements such as carbon and sulfur, and energy dispersive X-ray fluorescence spectrometry for other elements. Microstructural characterization was performed with the support of scanning electron microscopy and energy dispersive spectroscopy. Regarding the VSI final application, the best results were achieved with the inserts air quenched and double tempered at 600 °C.

    Palavras-Chave: heat treatments; powder metallurgy; steels; valves; air; quenching

    Como referenciar este item
    Icon

  • IPEN-DOC 26951

    SANTOS, ADIMIR dos ; SILVA, GRACIETE S. de A. e . The impact of the new nuclear data libraries on the isothermal reactivity coefficient determination. In: INTERNATIONAL CONFERENCE ON MATHEMATICS AND COMPUTATIONAL METHODS APPLIED TO NUCLEAR SCIENCE AND ENGINEERING, April 16-20, 2017, Jeju, Korea. Proceedings... Daejeon, Korea: Korean Nuclear Society, 2017.

    Abstract: The impact of the new released evaluations for 235U, 238U, 16O, and S(α,β) for hydrogen bound water, in the determination of the isothermal reactivity coefficient of thermal reactors fueled with slightly enriched uranium is addressed in this work. The experiment to serve as a benchmark for this kind of reactor response is the inversion point of the isothermal reactivity coefficient of the IPEN/MB-01 reactor which was recently approved to be included in the IRPhE handbook. The theoretical analyses have been performed employing the coupled NJOY/AMPX-II/TORT systems. The analyses reveal that the major impacts are due to new data of 235U and to those of S(α,β) for hydrogen bound in water. The (C-E)/E values when considering the new data from these libraries show an excellent progress in the theoretical determination of this very important reactor response. The new data for 238U and 16O show very little impact on the analysis. This work supports the developments recently adopted in the generation of the new nuclear data libraries for 235U and for the S(α,β) for hydrogen bound in water.

    Palavras-Chave: benchmarks; nuclear data collections; reactivity coefficients; slightly enriched uranium; thermal reactors; uranium 235; uranium 238

    Como referenciar este item
    Icon

  • IPEN-DOC 26946

    ANDRADE, GABRIEL M.; SILVA, LEONARDO G.A. ; REZENDE, MAIRA de L.. Efeito da radiação ionizante no Etileno Propileno Dieno (EPDM) / Effect of ionizing radiation in Ethylene Propylene Diene (EPDM). In: CONGRESSO BRASILEIRO DE POLIMEROS, 14., 22-26 de outubro, 2017, Águas de Lindóia, SP. Anais... 2017. p. 1917-1921.

    Abstract: A substituição do processo de vulcanização ou reticulação da borracha para a produção de artefatos de diversos segmentos torna-se interessante do ponto de vista ambiental e financeiro, pois evita o emprego de enxofre e de peróxidos. A radiação ionizante empregada em elastômeros pode ocasionar diversas alterações estruturais e, entre essas possibilidades destaca-se a reticulação. Este trabalho tem por objetivo avaliar as alterações provocadas no EPDM após aplicação de diferentes doses de radiação proveniente de feixes de elétrons, buscando verificar a possibilidade deste processo na substituição da vulcanização convencional aplicada em borrachas. Os efeitos da radiação foram investigados por meio de ensaios mecânicos e determinação da densidade de reticulação. Os resultados sugerem que houve cisão de cadeias, bem como a formação de novas ligações entre as macromoléculas, variando a intensidade conforme a dose aplicada, o que indica a possibilidade de os feixes de elétrons substituírem a vulcanização convencional.

    Palavras-Chave: cross-linking; cross-linking; density; ethylene propylene diene polymers; mechanical tests; radiation doses; radiation effects

    Como referenciar este item
    Icon

  • IPEN-DOC 26945

    LEVY, D. ; SORDI, G.M.A.A. ; VILLAVICENCIO, A.L.C.H. . Divulgación científica: un desafío y una necesidad para aproximar ciencia y sociedad. In: SIMPOSIO INTERNACIONAL SOBRE EDUCACION, CAPACITACION, EXTENSION Y GESTION DEL CONOCIMIENTO EN TECNOLOGIA NUCLEAR, 2., 13-17 de novembro, 2017, Buenos Aires, Argentina. Anais... 2017.

    Abstract: La Irradiación de alimentos trae grandes contribuciones a la seguridad alimentaria, además de los impactos en las esferas social y económica del país. En Brasil, sin embargo, aún es grande el desconocimiento: miedos y preconceptos infundados tiemblan la confianza del consumidor. Investigadores del IPEN emprendieron una investigación ante el público en general. Los mayores ejemplos de aplicaciones de la tecnología nuclear parecen ser, en el imaginario popular, armas de destrucción masiva y accidentes nucleares. Entre las mayores preocupaciones de los entrevistados, están la cuestión de la seguridad en relación a la salud, exposición a la radiación y contaminación del medio ambiente. En 2016 se inició una acción para la divulgación científica a gran escala. En la llamada Sociedad de la Información, la acción se centra en el desarrollo de cursos virtuales destinados al público en general. El proceso involucró una amplia investigación sobre las posibilidades de acceso a Internet en los domicilios brasileños y perspectivas futuras. Los cursos tienen como objetivo llevar al conocimiento del público cuestiones pertinentes a la irradiación de alimentos de la agricultura a la mesa del consumidor, entre las cuales, un mini curso completamente destinado a la comunicación de la protección radiológica, una vez que la investigación apunta entre las mayores preocupaciones de la población la Seguridad, contaminación y efectos maléficos de la radiación. Esta acción pretende proporcionar al público en general material confiable y de fácil comprensión para la diseminación del conocimiento en los más diversos sectores de la sociedad. La alimentación es una de las grandes cuestiones brasileñas y la irradiación de alimentos es una técnica segura y confiable para responder a esta demanda. Los consumidores hacen juicios intuitivos según su percepción de riesgo y el desconocimiento conduce a miedos infundados y conclusiones equivocadas. Se espera con esta iniciativa acercar la sociedad y la comunidad científica. Una acción ciudadana para promover la conciencia crítica llevando al ciudadano a cuestionar la realidad, interpretar las informaciones de la mídia y construir opiniones científicamente fundamentadas.

    Palavras-Chave: irradiation; nuclear energy; communications; information dissemination; scientific personnel; public information; public opinion

    Como referenciar este item
    Icon

  • IPEN-DOC 26904

    GIOVEDI, C.; MARTINS, M.R.; ABE, A. ; MUNIZ, R.O.R. ; GOMES, D.S. ; SILVA, A.T. . Fuel performance assessment of enhanced accident tolerant fuel using iron-based alloys as cladding. In: TOPFUEL, 30 September - 04 October, 2018, Prague, Czech Republic. Proceedings... Brussels, Belgium: European Nuclear Society, 2018.

    Abstract: In the framework of the Enhanced Accident Tolerant Fuel (EATF) program, one important tool to assess the behaviour of new materials under irradiation is the use of fuel performance codes. For this, it is necessary to modify conventional fuel performance codes to introduce the properties of the materials to be studied. The aim of this paper is to present some preliminary results obtained using modified versions of the FRAPCON code adapted to evaluate the performance as cladding of two different types of iron-based alloys as cladding: stainless steel (AISI 348), and FeCrAl alloy, including a preliminary sensitivity analysis. The results obtained using the modified versions of the codes were compared to those obtained for zirconium-based alloys using the original code version. The results have shown and confirmed that iron-based alloys are one of the promising candidates to be used as EATF cladding in PWR.

    Palavras-Chave: iron base alloys; accident-tolerant nuclear fuels; fuel-cladding interactions

    Como referenciar este item
    Icon

  • IPEN-DOC 26903

    LEVY, D.S. ; RAMOS, F.C. ; SORDI, G.M.A.A. . The impact of wrong mass media communication on citizens' perception of radiation risks. In: CONGRESO REGIONAL DE SEGURIDAD RADIÓLOGICA Y NUCLEAR, 11th, April 16-20, 2018, La Habana, Cuba. Proceedings... 2018.

    Abstract: In Knowledge Society, Internet and mass media contribute to build an inclusive informed society, providing information about all fields of knowledge. Nevertheless, nuclear sciences remain a mystery for a great fraction of the Brazilian population. Controversies on the biological effects of radiation distort and confuse public's perceptions of radiation risks and benefits. Internet reports that the exposure to indoor radon is a risk factor for lung cancer. Internet reports that the radioactive monazitic sand brings health benefits. It is not easy for the general public to understand contradictions and to identify reliable sources. Scientific community is expected to communicate about the impacts of ionizing radiation in daily life. Nevertheless, the public does not read highly specialized papers. There seem to be a gap between society and the scientific community. On the other hand, anti-nuclear information seems to be easily understood. This paper discusses wrong mass media information delivered all over the country, for kids and adults, in very simple language, through cartoons, comics books, newspapers and educational sites, among others. The article brings examples of newspapers errors due to misinformation, anti-nuclear didactic material plenty of omissions and wrong information delivered to children. People fear what they do not understand. People fear the harmful effects of ionizing radiation to human health and the environment. Risk perception and risk acceptance are a matter of education and properly communication. It is a must to invest in properly scientific divulgation about the risks and benefits of nuclear sciences that impact in citizens´ everyday life, such as medical applications, industrial applications and nuclear power generation.

    Palavras-Chave: nuclear power; public information; knowledge base; public opinion; radiation protection

    Como referenciar este item
    Icon

  • IPEN-DOC 26902

    COUTO, CAMILA P. ; COSTA, ISOLDA ; PANOSSIAN, ZEHBOUR; COLOSIO, MARCO A.; CAMPOS, LUIZ G.F.P. de; ROSSI, JESUALDO L. . Corrosion resistance and adhesion evaluation of press hardened steel 22MnB5 coated with AlSi and ZnNi in cyclic corrosion testing. In: CONGRESSO BRASILEIRO DE CORROSÃO, 38.; INTERNATIONAL CORROSION MEETING, 7th; CONBRASCORR PARA INSPETORES DE PINTURA, 2.; CONCURSO DE FOTOGRAFIA DE CORROSÃO E DEGRADAÇÃO DE MATERIAIS, 21.; EXPOSIÇÃO DE TECNOLOGIAS PARA PREVENÇÃO E CONTROLE DA CORROSÃO, 37., 14-18 de maio, 2018, São Paulo, SP. Proceedings... Rio de Janeiro, RJ: Associação Brasileira de Corrosão, 2018. p. 1-6.

    Abstract: AlSi coating has been the most applied on press hardening steels - PHS. However, alternative coatings such as Zn-based alloys are under investigation. This paper has the objective of evaluating the corrosion resistance of the 22MnB5 steel, coated either with hot-dip AlSi or electroplated ZnNi, by means of cyclic corrosion test. Automotive parts of ZnNi coated PHS steel were tested in two different conditions: after hot stamping, and after hot stamping plus sandblasting. Other parts coated with AlSi were evaluated just in the after hot stamping condition. The cyclic corrosion test results showed that all metallic coated samples had excellent corrosion performance. However, the ZnNi coated in the as hot stamped condition, presented the best corrosion performance during testing. Surface coating cracks were found in all parts. Moreover, the adhesion was evaluated after 28 and 68 cycles in creepback area and the results showed that there was no loss of adhesion after the cyclic corrosion tests. The corrosion resistance results pointed that the electroplated ZnNi is a potential alternative to AlSi coating.

    Palavras-Chave: corrosion resistance; adhesion; aluminium alloys; silicon alloys; steels

    Como referenciar este item
    Icon

  • IPEN-DOC 26901

    QUINI, J.G. ; MARINUCCI, G. . Evaluation of urethane adhesive-composite joints under different environmental conditions. In: EUROPEAN CONFERENCE ON COMPOSITE MATERIALS, 18th, June 24-28, 2018, Athens, Greece. Proceedings... Patras, Greece: European Society for Composite Materials, 2018. p. 1-6.

    Abstract: Structural adhesives technology has changed the concept of joints bonding different materials in a unique solid assembly and making them part of the structures. These joints not only increase strength and stiffness but also reduce weight, which is important, for instance, for vehicles and airplanes. The present study reports the results of applying urethane structural adhesives in automotive components. RTM, SMC, ABS thermoplastic and galvanised steel samples was evaluated under temperaturem time, humidity and destilled water. The results show very good adherence between the adhesive and the substrates under these conditions.

    Palavras-Chave: adhesives; urethane; shear; composite materials; joints

    Como referenciar este item
    Icon

  • IPEN-DOC 26900

    BELCHIOR JUNIOR, A. ; SANTOS, A.A.C. dos; FREITAS, R.L.; SOARES, H.V.; JUNQUEIRA, F.C. ; MANTECON, J.G. ; MATTAR NETO, M. ; MENZEL, S.C. ; TORRES, W.M. ; UMBEHAUN, P.E. . Analytical and experimental analysis on safety related aspects of the RMB research reactor. In: INTERNATIONAL CONFERENCE ON RESEARCH REACTORS: ADDRESSING CHALLENGES AND OPPORTUNITIES TO ENSURE EFFECTIVENESS AND SUSTAINABILITY, November 25-29, 2019, Buenos Aires, Argentina. Proceedings... Vienna, Austria: International Atomic Energy Agency, 2020.

    Abstract: This paper presents some numerical and experimental safety related activities developed at the Brazilian Multipurpose Reactor (RMB) project by CNEN research institutes. Brief comments on the models and results are presented with emphasis to their relation to the safe design and operation of the reactor. Thermal-hydraulic analysis for Siphon Breaker of the Core Cooling System (CCS); pools hot water layer; core chimney of CCS and spent fuel transport cask are presented, showing results, advantages, difficulties and drawbacks for each analyzed case. All are very distinct cases, involving phenomena that range from two-phase flow and thermal-stratification to lead melting. Beside the one-dimensional thermal hydraulic system Code RELAP5, Computational Fluid Dynamics (CFD) is shown to play an important role in the analysis being performed as it can detail the flow and temperature fields of complex components and phenomena, which are extremely difficult to model analytically or experimentally. Two experimental circuits designed to test RMB fuel elements performance are also presented.

    Palavras-Chave: computerized simulation; reactor design; reactor operation; reactor safety; rmb reactor; safety analysis; spent fuels; stratification; thermal hydraulics; two-phase flow

    Como referenciar este item
    Icon

  • IPEN-DOC 26899

    SANTAELLA, CESAR R.K. ; CORREA, OLANDIR V. ; COTINHO, SAMUEL P.; PILLIS, MARINA F. . Propriedades das camadas termodifundidas de boro e lantânio no aço AISI 1045. In: INTERNATIONAL FORGING CONFERENCE, 23rd; NATIONAL SHEET METAL FORMING CONFERENCE, 22nd; INTERNATIONAL SHEET METAL FORMING CONFERENCE, 9th; BRDDRG CONGRESS, 6th; INTERNATIONAL CONFERENCE ON MATERIALS AND PROCESSES FOR RENEWABLE ENERGIES, 9th; INTERNATIONAL CONFERENCE ON SURFACE ENGINEERING IN MATERIAL FORMING, 2nd, October 2-4, 2019, Porto Alegre, RS. Proceedings... 2019.

    Abstract: A boretação é um processo termoquímico de difusão de boro no estado sólido que tem por objetivo aumentar a resistência ao desgaste através da formação de uma camada dura de boretos de ferro na superfície do aço. As propriedades dessas camadas podem ser alteradas com a difusão combinada de boro com outros elementos químicos simultaneamente, como por exemplo o alumínio, para elevar a resistência à oxidação, ou o vanádio, para elevar a resistência ao desgaste superficial. Neste trabalho são apresentados os resultados obtidos com a difusão combinada de boro e lantânio.

    Palavras-Chave: lanthanum; boron; borides; steels

    Como referenciar este item
    Icon

  • IPEN-DOC 26898

    SABUNDJIAN, INGRID T. ; NEGRAO, BIANCA G. ; SÁ, ANA P.N. de ; VILLAVICENCIO, ANNA L.C.H. . Analise microbiológicas de fermento biológico seco processado por radiação gama. In: CONGRESSO BRASILEIRO DE CIÊNCIA E TECNOLOGIA DE ALIMENTOS, 26., 13-16 de agosto, 2018, Belém, PA. Anais... Belém, PA: Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2018. p. 6007-6014.

    Abstract: O objetivo do trabalho foi identificar se houve alteração no crescimento de UFC em placa e na viabilidade de leveduras e bactérias totais em fermento biológico seco tratado por diferentes doses de radiação gama e determinar a dose D10 para bactérias Totais e Leveduras a fim de analisar se o processamento promoveu algum benefício sem causar inviabilidade do mesmo. As diferentes amostras de fermento biológico foram irradiadas com doses de 0 (controle); 0,5; 1; 2 e 3kGy no Centro de Tecnologia das Radiações do (IPEN/CNEN – SP) em fonte de 60Co (Gammacell-220), com taxa de dose de 3,51kGy/h. O aumento da dose de radiação provocou uma diminuição na contagem de UFC de leveduras e de bactérias totais, bem como, na frequência de células viáveis de leveduras. A dose de radiação necessária para eliminar 90% da população leveduriforme ficou entre 1,10 e 2,23kGy e para a população bacteriana variou entre 2,31 e 2,95kGy. Nos resultados são demonstrados claramente os pontos negativos da aplicação de radiação ionizante em fermento biológico seco, pois o intervalo de D10 encontrado para bactérias totais é superior ao encontrado para leveduras. Sendo assim, torna-se inviável a utilização deste recurso para a melhora da qualidade do produto.

    Palavras-Chave: bacteria; yeasts; ionizing radiations; gamma radiation; fluorescence

    Como referenciar este item
    Icon

  • IPEN-DOC 26897

    NEGRAO, BIANCA G. ; VILLAVICENCIO, ANNA L.C.H. ; ARTHUR, VALTER. Ionizing radiation as a phytosanitary treatment in Zea mays L. var. everta. In: CONGRESSO BRASILEIRO DE CIÊNCIA E TECNOLOGIA DE ALIMENTOS, 26., 13-16 de agosto, 2018, Belém, PA. Anais... Belém, PA: Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2018. p. 6022-6028.

    Abstract: Quarantine treatment has been used to provide protection against pests by eliminating the stages evolutionary cycle that may be associated with the product. Popcorn is used in the food industry in the form of dry beans and is an economic option for producers and their sale generates foreign exchange worldwide. The aim of this work is to evaluate the effects of gamma radiation on seeds of popcorn (Zea mays L. var. everta). The seeds was be purchased in the retail trade of São Paulo city, later was be infested in the Laboratory of Food Irradiation at IPEN, then was be submitted to different doses of gamma radiation: 0, 25, 50, 75 and 100 Gy. A Gammacell-220 at 60Co source at a dose rate of 1.4 kGy / hr at the Technology Center of Radiation (CTR) IPEN-CNEN / SP. Each treatment was consisting of 3 replicates with 100 grams of popcorn kernels. Samples was be packed and stored at a temperature of 25 ± 2 ° C and relative humidity of 70 ± 5%. By the results, it can conclude that the dose of 75 Gy can be indicated to control insects Sitophilus zeamais in popcorn.

    Palavras-Chave: disinfestation; quarantine; therapy; storage; insects

    Como referenciar este item
    Icon

  • IPEN-DOC 26896

    KOIKE, AMANDA C.R. ; SÁ, ANA P.N. de ; ARAUJO, ELIAS da S.; ALMEIDA-MURADIAN, LIGIA B. de; VILLAVICENCIO, ANNA L.C.H. . Evaluation of carotenoids in edible flowers processed by radiation. In: CONGRESSO BRASILEIRO DE CIÊNCIA E TECNOLOGIA DE ALIMENTOS, 26., 13-16 de agosto, 2018, Belém, PA. Anais... Belém, PA: Sociedade Brasileira de Ciência e Tecnologia de Alimentos, 2018. p. 5518-5524.

    Abstract: The use of flowers in the gastronomy has been growing in recent years, the world market for edible flowers is in full expansion, this kind of flower ensure a special note in the taste and in the decoration, and improve the nutritional aspects when added in food products. Its beneficial properties in health maintenance are also recognized, requiring new approaches to improve its conservation and safety. Food irradiation is an economically viable technology both in quality and safety. The purpose of this study was to evaluate carotenoids in Rosa chinensis and Tagete patula flowers submitted to gamma irradiation and electron beam doses of 0.5, 0.8 and 1.0 kGy. High performance liquid chromatography (HPLC) was used to carotenoids determination. The most abundant carotenoids were α-carotene for both species of flowers studied. In general, gamma-irradiated samples presented higher amounts in carotenoids (lutein and alfa-carotene) independently of the applied dose. However, the interaction between irradiation and samples did not affect carotenoids present in edible flowers petals.

    Palavras-Chave: food processing; irradiation; chromatography; flowers

    Como referenciar este item
    Icon

  • IPEN-DOC 26860

    MESQUITA, ANDERSON S. ; ZAHARESCU, TRAIAN; SILVA, LEONARDO G.A. . Efeitos da radiação ionizante no processo de degradação da blenda de DGEBA/EPDM / Electron beam effect on the degradation process of DGEBA/EPDM blend. In: CONGRESSO BRASILEIRO DE POLÍMEROS, 15., 27-31 de outubro, 2019, Bento Gonçalves-RS. Anais... São Carlos, SP: Associação Brasileira de Polímeros, 2019.

    Abstract: A blenda de DGEBA/EPDM pode ser usada para revestir a superfície de outros materiais e protegê-los contra condições térmicas elevadas. O objetivo deste trabalho foi obter, caracterizar e irradiar a blenda de DGEBA/EPDM e estudar os efeitos da radiação ionizante e comparar suas propriedades com uma blenda de DGEBA/EPDM não irradiada. Os compostos possuem 0, 25 e 50% em massa da resina epóxi de DGEBA. O processo de irradiação dos compostos foi feito com doses de 30 e 60 kGy desde um acelerador de elétrons. Posteriormente, estas blendas foram caracterizadas por ensaios de quimiluminescência e espectroscopia de absorção por transformada de Fourier (FTIR). Concluiu-se que as blendas irradiadas de DGEBA/EPDM podem ser usadas em aplicações específicas de acordo com a temperatura de degradação das blendas. Suas propriedades foram satisfatórias para aplicações que necessitem desse tipo de material.

    Palavras-Chave: electron beams; epoxides; ethylene propylene diene polymers; fourier transformation; infrared spectra; ionizing radiations; luminescence; protective coatings; radiation dose units; resins

    Como referenciar este item
    Icon

  • IPEN-DOC 26859

    CHELIGA, PEDRO; MACHADO, ALISSON R.; ROSSI, WAGNER de . Efeito da microtexturização a laser em ferramentas de metal duro na temperatura de corte no torneamento do aço ABNT 1020 / Effect of laser microtexturization on cemented carbide tools in the cutting temperature in turning of ABNT 1020 steel. In: CONGRESO IBEROAMERICANO DE INGENIERÍA MECÁNICA, 14th, November 12-15, 2019, Cartagena de Indias, Colombia. Proceedings... 2019. p. 1-9.

    Abstract: A textura de uma superfície é formada por asperidades e depressões normalmente não ordenadas. Uma superfície organizada e ordenada altera as propriedades e o comportamento tribológico de uma peça ou ferramenta. Dentre as técnicas utilizadas para alterar uma superfície com precisão, se destaca a microtexturização a laser. Trata-se de uma técnica relativamente nova na fabricação de texturas precisas em superfícies quaisquer, podendo ser utilizada para diversas finalidades. Este trabalho tem como objetivo estudar o efeito da microtexturização a laser em ferramentas de corte de metal duro na temperatura da interface cavaco-ferramenta, no torneamento do aço ABNT 1020. Foram desenvolvidas texturas com laser de pulsos ultracurtos (femtosegundos - 10−15 s), numa área de 4 mm x 4 mm na superfície de saída de bits de metal duro, classe P30, com cunha retificada e aresta arredondada previamente. Foram utilizados quatro tipos diferentes de texturas, canais paralelos à aresta principal de corte, canais perpendiculares à aresta principal de corte, canais oblíquos (a 45º) à aresta principal de corte e do tipo “Chevron”. Estas ferramentas foram utilizadas em ensaios individuais para medição da temperatura da interface cavaco ferramenta, pelo método do termopar ferramenta-peça, no torneamento, variando-se a velocidade de corte e o avanço, tanto na condição a seco como usando MQL. Ferramentas sem texturas também foram utilizadas para comparação. Os resultados mostraram que as microtexturas auxiliam na redução da temperatura de corte, em especial para a ferramenta com microtextura paralela a aresta de corte.

    Palavras-Chave: machining; microstructure; texture; cutting; lasers

    Como referenciar este item
    Icon

  • IPEN-DOC 26858

    BERGAMASCHI, VITOR; CARNEIRO, MARCELO B.; ROSSI, WAGNER de ; NEVES, MAURICIO D.M. . Tratamento térmico de endurecimento por laser pulsado de Nd:YAG em aço-rápido / Hardening heat treatment by Nd:YAG pulsed laser in high-speed steel. In: CONGRESSO BRASILEIRO DE ENGENHARIA DE FABRICAÇÃO, 10., 5-7 de agosto, 2019, São Carlos, SP. Anais... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas, 2019.

    Abstract: O uso do laser no processamento de materiais é uma área de pesquisa em ascensão, sendo que o mesmo tem sido utilizado em processos avançados de fabricação e em tratamentos superficiais. Quanto aos tratamentos superficiais, destaca-se o de endurecimento seletivo, que provoca o aumento de dureza da superfície do material da peça, possibilitando a redução do desgaste e aumento no tempo de vida do componente. Nesse sentido, o objetivo do trabalho foi avaliar a influência de alguns parâmetros de aplicação do laser pulsado de Nd:YAG na alteração sub-superficial de uma amostra de aço-rápido sinterizado (HSS/PM). Para tanto, foi realizada a preparação metalográfica da seção transversal da amostra atacada pelo laser, para em seguida realizar as caracterizações por microscopia óptica e eletrônica de varredura, mecânica através do ensaio de microdureza Vickers e física para a identificação das fases formadas através da difração de raios-X (DRX). A análise dos resultados mostrou que os parâmetros do laser influenciaram significativamente na profundidade da alteração sub-superficial, da mesma forma que promoveram variação de dureza, provavelmente, devido a formação de martensita e carbonetos detectadas em DRX.

    Palavras-Chave: lasers; hardness; steels; microhardness

    Como referenciar este item
    Icon

  • IPEN-DOC 26857

    ALMEIDA, GUSTAVO S. de; COELHO, REGINALDO T.; CARNEIRO, MARCELO B.; BARBOSA, PATRICIA A.; ROSSI, WAGNER de ; SAMAD, RICARDO E. ; VIEIRA JUNIOR, NILSON D. ; MACHADO, ALISSON R.. Avaliação do desempenho de ferramenta de metal duro texturizada por laser de pulsos ultracurtos / Evaluation of cemented carbide tool texturized by ultrashort laser pulses. In: CONGRESSO BRASILEIRO DE ENGENHARIA DE FABRICAÇÃO, 10., 5-7 de agosto, 2019, São Carlos, SP. Anais... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas, 2019.

    Abstract: A texturização por laser de pulsos ultracurtos provoca uma ablação com mínimo dano térmico, preservando as características adjacentes do material ablacionado. Deste modo, torna-se possível gerar microtexturas na superfície de saída da ferramenta de usinagem, buscando melhoria de desempenho. Este trabalho realiza uma comparação entre duas ferramentas de corte de metal-duro, TPUN 160304, sendo uma texturizada e a outra de referência (nãotexturizada), durante o torneamento de um aço inoxidável austenítico (V304UF). Para isto, os parâmetros de corte foram mantidos constantes. Avaliou-se a força de usinagem, o desgaste de flanco da ferramenta, além da rugosidade produzida sobre a peça. Os resultados mostraram um melhor comportamento para ferramenta texturizada.

    Palavras-Chave: texture; machining; austenitic steels; stainless steels

    Como referenciar este item
    Icon

  • IPEN-DOC 26855

    GIOVEDI, C.; MARTINS, M.R.; ABE, A. ; REIS, R. ; SILVA, A.T. . Reactivity initiated accident assessment for ATF cladding materials. In: TECHNICAL MEETING ON MODELLING OF FUEL BEHAVIOUR IN DESIGN BASIS ACCIDENTS AND DESIGN EXTENSION CONDITIONS, May 13-16, 2019, Shenzhen, China. Proceedings... Vienna, Austria: International Atomic Energy Agency, 2020. p. 155-161. (IAEA-TECDOC-1913).

    Abstract: Following the experience that came from the Fukushima Daiichi accident, one possible way of reducing risk in a nuclear power plant operation would be the replacement of the existing fuel rod cladding material (based on zirconium alloys) by another materials which could fulfill the requirements of the accident tolerant fuel (ATF) concept. In this sense, ATF should be able to keep the current fuel system performance under normal operation conditions; moreover, it should present superior performance than the existing conventional fuel system (zirconium-based alloys and uranium dioxide) under accident conditions. The most challenging and bounding accident scenarios for nuclear fuel systems in Pressurized Water Reactors (PWR) are Loss of Coolant Accident (LOCA) and Reactivity Initiated Accident (RIA), which are postulated accidents. This work addresses the performance of ATF using iron-based alloys as cladding material under RIA conditions. The evaluation is carried out using modified versions of the coupled system FRAPCON/FRAPTRAN. These codes were modified to include the material properties (thermal, mechanical, and physics) of an iron-based alloy, specifically FeCrAl alloy. The analysis is performed using data available in the open literature related to experiments using conventional PWR fuel system (zirconium-based alloys and uranium dioxide). The results obtained using the modified code versions are compared to those of the actual existing fuel system based on zircaloy-4 cladding using the original versions of the fuel performance codes (FRAPCON/FRAPTRAN).

    Palavras-Chave: accident-tolerant nuclear fuels; charges; cladding; comparative evaluations; currents; fuel rods; fuel systems; fukushima daiichi nuclear power station; hazards; zircaloy 4; iron; loss of coolant; nuclear power plants; operation; performance; pwr type reactors; reactivity-initiated accidents; steady-state conditions; uranium dioxide

    Como referenciar este item
    Icon

  • IPEN-DOC 26854

    GOMES, D.S. ; ABE, A. ; SILVA, A.T. ; MUNIZ, R.O.R. ; GIOVEDI, C.; MARTINS, M.R.. Assessment of high conductivity ceramic fuel concept under normal and accident conditions. In: TECHNICAL MEETING ON MODELLING OF FUEL BEHAVIOUR IN DESIGN BASIS ACCIDENTS AND DESIGN EXTENSION CONDITIONS, May 13-16, 2019, Shenzhen, China. Proceedings... Vienna, Austria: International Atomic Energy Agency, 2020. p. 95-101. (IAEA-TECDOC-1913).

    Abstract: After the Fukushima Daiichi accident, the high conductivity ceramic concept fuel has been revisited. The thermal conductivity of uranium dioxide used as nuclear fuel is relatively low, as consequence fuel pellet centerline reaches high temperatures, high fission gas release rate, increase of fuel rod internal pressure reducing the safety thermal margin. Several investigations had been conducted in framework of ATF (Accident Tolerant Fuel) using different additives in ceramic fuel (UO2) in order to enhance thermal conductivity in uranium dioxide pellets. The increase of the thermal conductivity of fuel can reduce the pellet centerline temperature, consequently less fission gas releasing rate and the low risk of fuel melting, hence improving significantly fuel performance under accident conditions. The beryllium oxide (BeO) has high conductivity among other ceramics and is quite compatible with UO2up to 2200°C, at which temperature it forms a eutectic. Moreover, it is compatible with zircaloy cladding, does not react with water, has a good neutronic characteristics (low neutron absorption cross-section, neutron moderation). This work presents a preliminary assessment of high conductivity ceramic concept fuel considering UO2-BeO mixed oxide fuel containing 10 wt% of BeO. The FRAPCON and FRAPTRAN fuel performance codes were conveniently adapted to support the evaluation of UO2-BeO mixed oxide fuel. The thermal and mechanical properties were modified in the codes for a proper and representative simulation of the fuel performance. Theobtainedpreliminary results show lower fuel centerline temperatureswhen compared to standard UO2 fuel, consequently promoting enhancement of safety margins during the operational condition and under LOCA accident scenario.

    Palavras-Chave: accident-tolerant nuclear fuels; beryllium oxides; uranium dioxide; zircaloy; ceramics; cladding; cross sections; eutectics; fission product release; fission products; fuel cans; fuel pellets; fuel rods; fukushima daiichi nuclear power station; loss of coolant; mechanical properties; melting; mixed oxide fuels; performance; safety margins; simulation; thermal conductivity

    Como referenciar este item
    Icon

  • IPEN-DOC 26853

    TERAM, ROGERIO; SANTOS, GIVANILDO A. dos; NASCIMENTO, MAURICIO S.; COUTO, ANTONIO A. ; SANTOS, VINICIUS T. dos; SILVA, MARCIO R. da. Influência do espaçamento dendrítico secundário na dureza da liga Cu-14Al-5Ni-5Fe obtida por solidificação unidirecional / Influence of the secondary dendritic spacing on the hardness of the Cu-14Al-5Ni-5Fe alloy obtained by unidirectional solidification. In: CONGRESO IBEROAMERICANO DE INGENIERÍA MECÁNICA, 14th, November 12-15, 2019, Cartagena de Indias, Colombia. Proceedings... 2019. p. 1-6.

    Abstract: O objetivo deste trabalho é analisar a influência do espaçamento dendrítico secundário, na dureza da liga Cu-14Al- 5Ni-5Fe após a realização de processo de solidificação. A liga foi solidificada em um dispositivo de solidificação direcional ascendente sendo o calor extraído através de refrigeração à água em uma base de aço SAE 1020. As medições dos espaçamentos dendríticos secundários foram obtidas por meio de microscopia óptica e software acoplado. As variáveis térmicas de solidificação como velocidade de deslocamento da isoterma liquidus (VL) e taxa de resfriamento (TR) foram avaliadas em função da distância da superfície de extração de calor. A dureza e os espaçamentos dendríticos secundários foram correlacionados com as posições de termopares devidamente dispostos no lingote. Em função dos resultados obtidos, conclui-se que maiores taxas de resfriamento apresentam espaçamentos dendríticos secundários mais refinados que propiciam maiores valores de dureza.

    Palavras-Chave: alloys; copper; solidification; hardness; dendrites

    Como referenciar este item
    Icon

  • IPEN-DOC 26823

    MACHADO, CARULINE de S.C. ; SILVA, REJANE M. da ; ARAUJO, JOAO V. de S. ; DONATUS, UYIME ; MILAGRE, MARIANA X. ; KLUMPP, RAFAEL E. ; ROSSI, JESUALDO L. ; COSTA, ISOLDA . Effects of chloride ion concentration on the corrosion behavior of the AA2198-T8 alloy. In: EUROPEAN CORROSION CONGRESS, September 9-13, 2019, Seville, Spain. Proceedings... 2019.

    Abstract: In this work, the influence of chloride ions concentration on the corrosion behavior of the AA2198-T8 alloy was evaluated. Immersion test and electrochemical analyses were performed in sodium chloride solutions of three concentrations, 0.001 mol L-1, 0.005 mol L-1 and 0.01 mol L-1. The results showed that the AA2198-T8 alloy was susceptible to localized corrosion (LC) and to severe localized corrosion (SLC) in all conditions investigated. The electrochemical results obtained by open circuit potential measurements, cyclic voltammetry and potentiodynamic polarization curves were associated with the corroded microstructure of the alloy. Although electrochemical techniques allowed differentiating the corrosion resistance as a function of chloride concentration, the result was strongly influenced by the corroded/uncorroded area ratio related to the SLC.

    Palavras-Chave: aluminium alloys; corrosion; electrochemical corrosion; electrochemistry; chlorides

    Como referenciar este item
    Icon

  • IPEN-DOC 26801

    SANTANA, TATIANA D.; ROSSI, WAGNER de ; BARBOSA, PATRICIA A.; CARNEIRO, MARCELO B.. Caracterização por microscopia óptica 3D de ferramenta de corte texturizada por laser de femtossegundos. In: COLÓQUIO DE USINAGEM, 23., 12-13 de dezembro, 2019, Uberlândia, MG. Anais... Uberlândia, MG: Universidade Federal de Uberlândia, 2019.

    Abstract: As superfícies possuem características que podem impactar no coeficiente de atrito, na adesão de filmes e células, na retenção de fluidos lubrificantes, em aspectos ópticos, químicos e mecânicos. Dessa forma, muitos parâmetros foram criados com intuito de caracterizar as superfícies após um determinado processo de manufatura. Em geral, os equipamentos utilizados para realizar tal tarefa são categorizados em com e sem contato com as superfícies em avaliação. Nos processos de usinagem convencional, condições severas de atrito na interface cavaco ferramenta aumentam o desgaste da ferramenta e reduz o seu tempo de vida. A habilidade do fluido de corte penetrar na zona de corte pode ser melhorada pela texturização da superfície de saída da ferramenta. Neste trabalho, uma ferramenta de corte foi texturizada com o uso de um laser de femtossegundos, e caracterizada com o uso de um microscópio óptico 3D com tecnologia confocal que garante medições precisas da topografia, sem contato.

    Palavras-Chave: texture; lasers; cutting tools; topography

    Como referenciar este item
    Icon

  • IPEN-DOC 26540

    ARAUJO, LEANDRO G. de ; WATANABE, NAOMI ; SILVA, THALITA T. ; TEIXEIRA, ANTONIO C.S.C.; VELOSA, ADRIANA C. de; MARUMO, JULIO T. . Oxidative degradation of organic compounds from sludge by ozonation: study of process. In: ANNUAL WASTE MANAGEMENT CONFERENCE, 45th, March 3-7, 2019, Phoenix, Arizona, USA. Proceedings... Tempe, Arizona, USA: Waste Management Symposia, 2019. p. 1-6.

    Abstract: This study investigates the performance of the ozonation process in the treatment of petroleum sludge from an offshore production platform situated in Brazil. The effect of operating conditions is studied such as the phase to be treated and the sludge/water ratio. Total organic carbon content increased in O2 and O3 experiments, mainly because of the mixing factor. The decrease of sludge mass was observed in a situation of forced mixing and with only ozone flow. The liquid phase indicated a high TOC value, but very low radioactive activities, whereas the solid phase did not present detectable TOC amounts but significant values of radioactive activity. More experiments and analyzes will be carried out to obtain more relevant results for future discussion.

    Como referenciar este item
    Icon

  • IPEN-DOC 26791

    BEU, CASSIA M.L. ; LANDULFO, EDUARDO . Threshold wind speed and turbulence under LLJs events at Ipero - Brazil. In: COMERON, ADOLFO (Ed.); KASSIANOV, EVGUENI I. (Ed.); SCHAFER, KLAUS (Ed.); PICARD, RICHARD H. (Ed.); WEBER, KONRADIN (Ed.); SINGH, UPENDRA N. (Ed.) SPIE REMOTE SENSING, September 9-12, 2019, Strasbourg, France. Proceedings... Bellingham, WA, USA: SPIE, 2019. p. 1115212-1 - 1115212-10. (Proceedings of SPIE Vol. 11152, Remote Sensing of Clouds and the Atmosphere XXIV). DOI: 10.1117/12.2532281

    Abstract: The threshold wind speed is a useful criterion in determining whether strong turbulence is generated within the Stable Boundary Layer (SBL), the layer where all surface emissions remain con ned during the night. Con dence turbulence estimates are extremely important for atmospheric transport and dispersion simulations, although due to its complex dinamics many aspects of the SBL are neglected by numerical models that, in turn, are the inputs and boundary conditions for the transport and dispersion simulations. Turbulence is especially important during severe episodies like hazardous material accidental releases, for example. Turbulence intensity can a ect the dispersion speed, released material concentration, and its reach. For many decades, remote sensing has been an important tool in lling the gap of information and providing advances in the atmospheric sciences. The doppler lidar is increasingly being used for micrometeoroly and Planetary Boundary Layer (PBL) studies because of its autonomy and long range capability, in contrast with traditional techniques as radioprobes and captive balloons. After 1 year of continuous measurements with a doppler lidar, it was possible to determine the threshold wind speed for Ipero, Sao Paulo, Brazil. Besides threshold wind speed, it was observed that the SBL turbulence has a straight relationship with the Low-Level Jets (LLJs) that frequently occur over the region. The vertical turbulence distribution depends greatly on the LLJ characteristics, which in turn is highly variable during its life cycle. The strong turbulence regime is associated to the stronger LLJs, that presents a more de ned pattern. In contrast, weak LLJs (that generate weaker SBL turbulence) present more dispersive characteristics in respect to the entire dataset. These di erences are seen both for the LLJ height as for the turbulence vertical pro le. These results will contribute for the atmospheric modeling and dispersion simulations, as well for the environmental studies at Ipero.

    Palavras-Chave: wind; earth atmosphere; dispersions; jets; boundary layers

    Como referenciar este item
    Icon

  • IPEN-DOC 26790

    MACEDO, FERNANDA M. ; CORREA, THAIS ; ARAUJO, ELAINE ; ANDRADE, IZABEL ; ARLEQUES, ANTONIO G. ; MIRANDA, JULIANA T. de M. ; SILVA, JONATAN da ; GUARDANI, ROBERTO; VESELOVSKII, IGOR; LANDULFO, EDUARDO . Correlation between two different real time data acquisition systems: LIDAR Raman and Cavity Ringdown Laser Spectroscopy, for CH4 as a fugitive gas, in São Paulo Metropolitan Area. In: COMERON, ADOLFO (Ed.); KASSIANOV, EVGUENI I. (Ed.); SCHAFER, KLAUS (Ed.); PICARD, RICHARD H. (Ed.); WEBER, KONRADIN (Ed.); SINGH, UPENDRA N. (Ed.) SPIE REMOTE SENSING, September 9-12, 2019, Strasbourg, France. Proceedings... Bellingham, WA, USA: SPIE, 2019. p. 111521D-1 - 111521D-14. (Proceedings of SPIE Vol. 11152, Remote Sensing of Clouds and the Atmosphere XXIV). DOI: 10.1117/12.2533111

    Abstract: Fugitive emissions, defined as unintended or irregular leaks of gases and vapors, these are an important source of pollutants to the atmosphere, which is difficult to monitor and control. These sources are present in different sites, including megacities like São Paulo that are growing in size and economic activity. At the same time, there is a remarkable growth in concerns about the environmental issues associated with these activities. In a constantly changing world, with increasing concentrations of greenhouse gases (GHGs), among them methane (CH4) and volatile organic compounds (VOC), mitigation of atmospheric emission of these gases to contain global warming, make field campaigns in the metropolitan region of São Paulo very relevant. Optical remote sensing techniques as lidar can attend the need for real time and trustable information on fugitive emissions. The Cavity Ringdown Laser Spectroscopy (CRDS) technique was adopted because it is widely used in the detection of gas samples that absorb light at specific wavelengths and also for their ability to detect mole fractions up to the parts per trillion level. The Raman lidar system used includes a commercial laser pulsed Nd:YAG Quantel S.A., model CFR 200, with wavelengths of 355 nm, 353 nm and 396 nm, 120 mJ pulse power, with laser repetition rate of 20 Hz and pulse width of 20 s, with a spatial resolution of 7,5 m. The system includes an ethernet interface, used together with LabView software to control the measurement and readout of the acquired data. The mixing ratio of CH4 can be observed within the planetary boundary layer. The measured methane profiles correlate with the acquisitions made with the CRDS, however, an additional contribution of control data in which the Raman lines detect with high sensitivity.

    Palavras-Chave: methane; optical radar; biomass; biofuels; raman effect; rotational states

    Como referenciar este item
    Icon

  • IPEN-DOC 26789

    GEORGESCU, GABRIEL; NUNES, MARCOS E.C.; OLIVEIRA, PATRICIA da S.P. de ; WIELENBERG, ANDREAS; NIEMELA, ILKKA; DUPUY, PATRICIA. RISKAUDIT and CNEN cooperation on probabilistic safety analysis. In: INTERNATIONAL TOPICAL MEETING ON PROBABILISTIC SAFETY ASSESSMENT AND ANALYSIS, 16th, April 28 - May 3, 2019, Charleston, South Carolina, USA. Proceedings... Illinois, USA: American Nuclear Society, 2019. p. 781-784.

    Abstract: The Brazilian project BR3.01/12 financed by European Union through the “Instrument for Nuclear Safety Cooperation” (INSC) programme and accomplished by RISKAUDIT organization (IRSN, GRS and STUK) constituted a support for enhancing and strengthening Brazilian Safety Authority (CNEN) expertise in regulatory and licensing activities, including probabilistic safety analysis (PSA), deterministic analysis and ageing management. The objectives of the project PSA task were to provide support to CNEN on the enhancement of its regulatory capability related to PSA development, review and applications and to provide support to CNEN on the review of the documents related to parts of Level 1 and 2 PSAs submitted by the utility, Eletronuclear (ETN), for the Brazilian NPPs of the CNAAA, which is a nuclear station located in Angra dos Reis, Rio de Janeiro. The activities focused on the updating and enhancement of Brazilian regulatory requirements for development and use of PSA, development of the Brazilian guide on regulatory review of PSA, support CNEN on the preliminary review of the PSAs for Angra 2 NPP, support CNEN on the management of Level 1 PSA computer codes and training CNEN staff on PSA methods, PSA review and PSA applications. The project, which started in May 2015, successfully ended in May 2018.

    Palavras-Chave: international cooperation; safety reports; radiation protection; safety analysis

    Como referenciar este item
    Icon

  • IPEN-DOC 26788

    SILVA, N.F. ; SILVA, T.F.; CASTRO, M.C. ; LUZ, H.N. da; CALDAS, LINDA V.E. . Garfield++ simulation of a TH-GEM based detector for standard mammography beam dosimetry. In: CONGRESSO BRASILEIRO DE METROLOGIA, 10.; CONGRESSO INTERNACIONAL DE METROLOGIA ELÉTRICA, 13.; CONGRESSO INTERNACIONAL DE METROLOGIA MECÂNICA, 5.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 6.; WORKSHOP DA REDE DE METROLOGIA QUÍMICA DO INMETRO, 4.; CONGRESSO BRASILEIRO DE METROLOGIA ÓPTICA, 3., 24-27 de novembro, 2019, Florianópolis, SC. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2019.

    Abstract: The TH-GEM based detector is a robust, simple to manufacture, high-gain gaseous electron multiplier. Its operation is based on a standard printed circuit board (PCB) coated on both sides by metallic material, perforated in a millimeter pattern, and immersed in gas. In order to study the feasibility of using TH-GEM type detectors in dosimetric applications for standard mammography beams, a prototype with adequate dimensions and materials was produced. The present work encompasses the calculations of electric fields by the Gmsh and Elmer software packages and the avalanche simulation using Garfield++ library of a TH-GEM detector filled with Ar/CO2 (70:30) mixture at atmospheric pressure.

    Palavras-Chave: charge transport; computer calculations; computer codes; computerized simulation; dosimetry; mammary glands; radiation detectors; standards

    Como referenciar este item
    Icon

  • IPEN-DOC 26787

    POLO, IVON O. ; CALDAS, LINDA V.E. . Fading estimation of SOL-GEL α-Al2O3 detectors. In: CONGRESSO BRASILEIRO DE METROLOGIA, 10.; CONGRESSO INTERNACIONAL DE METROLOGIA ELÉTRICA, 13.; CONGRESSO INTERNACIONAL DE METROLOGIA MECÂNICA, 5.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 6.; WORKSHOP DA REDE DE METROLOGIA QUÍMICA DO INMETRO, 4.; CONGRESSO BRASILEIRO DE METROLOGIA ÓPTICA, 3., 24-27 de novembro, 2019, Florianópolis, SC. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2019.

    Abstract: The OSL and the TL techniques are used in several fields of radiation dosimetry. The dosimeters are affected by a signal loss in the time between the irradiation and readout (fading). This undesirable characteristic can cause an underestimation of the irradiation dose. The fading estimation of SOL-GEL α-Al2O3 with several different concentrations of impurities is reported. The thermal fading and the light-induced fading of the SOL-GEL α-Al2O3 detectors were estimated. Furthermore, the exponential equations used to interpolate the experimental results were presented.

    Palavras-Chave: aluminium nitrates; attenuation; dosemeters; dosimetry; energy losses; radiation quality; thermoluminescent dosimetry

    Como referenciar este item
    Icon

  • IPEN-DOC 26786

    SANTOS, WILLIAM S. ; SANTOS, CARLA J.; SILVA, ALINE F. da; SOUZA, SAMARA P.; NEVES, LUCIO P.; BELINATO, WALMIR; CALDAS, LINDA V.E. ; PERINI, ANA P.. Dose evaluation in breast brachytherapy using different 125I seeds: a Monte Carlo approach. In: CONGRESSO BRASILEIRO DE METROLOGIA, 10.; CONGRESSO INTERNACIONAL DE METROLOGIA ELÉTRICA, 13.; CONGRESSO INTERNACIONAL DE METROLOGIA MECÂNICA, 5.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 6.; WORKSHOP DA REDE DE METROLOGIA QUÍMICA DO INMETRO, 4.; CONGRESSO BRASILEIRO DE METROLOGIA ÓPTICA, 3., 24-27 de novembro, 2019, Florianópolis, SC. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2019.

    Abstract: A very common type of cancer among women is the breast cancer. The treatment choice depends, among several factors, on the clinical stage of the disease and the age. One way to treat breast cancer is the permanent breast seed implant, with Iodine-125 (125I). Since they present some advantages: possibility to treat solid tumors, near the tumor site, induction of little trauma and strong lethality to cancer cells. In Brazil, a new 125I seed was developed at the Instituto de Pesquisas Energéticas e Nucleares to be applied in brachytherapy. Given the large number of women diagnosed with breast cancer, in this work, the dose determination in organs and tissues was undertaken, considering this new seed and a commercial, Amersham 6711-Oncoseed®, employing the Monte Carlo method. Moreover, for a better understanding of the radiation doses delivered to different patients, the breast volumes were modified. For this purpose, the MCNPX Monte Carlo code was utilized coupled with female virtual anthropomorphic phantoms. The results pointed out the highest dose values for the breast and skin. Furthermore, the dose results for both types of seeds were very similar.

    Palavras-Chave: mammary glands; neoplasms; brachytherapy; monte carlo method; radiation doses

    Como referenciar este item
    Icon

  • IPEN-DOC 26785

    SANTOS, WILLIAM S. ; NEVES, LUCIO P.; PERINI, ANA P.; SANTOS, CARLA J.; BELINATO, WALMIR; SILVA, ROGERIO M.V.; SOARES, MARIA R.; VALERIANO, CAIO C.; CALDAS, LINDA V.E. . Computational modelling of cervix uterus radiation procedure using a virtual anthropomorphic phantom and the MCNPX code. In: CONGRESSO BRASILEIRO DE METROLOGIA, 10.; CONGRESSO INTERNACIONAL DE METROLOGIA ELÉTRICA, 13.; CONGRESSO INTERNACIONAL DE METROLOGIA MECÂNICA, 5.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 6.; WORKSHOP DA REDE DE METROLOGIA QUÍMICA DO INMETRO, 4.; CONGRESSO BRASILEIRO DE METROLOGIA ÓPTICA, 3., 24-27 de novembro, 2019, Florianópolis, SC. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2019.

    Abstract: There is a serious, and growing, concern about the increased risk of the emergence of a secondary cancer, radio-induced, associated with radiotherapy treatments. To assess the radiation doses to organs outside the target volume, in this work, several computational exposure scenarios were modelled, based on Monte Carlo simulation (MCNPX code). A Varian 2100c accelerator, and a female virtual anthropomorphic phantom were used, in a simulated treatment of cervical cancer. The determination of the dispersed dose would be important for assessing the risk in different organs or tissues. Four treatment fields were applied, varying the gantry angle. It was possible to observe that the conversion factors for equivalent dose were higher for the AP projection. For the RLAT and LLAT projections, the results were similar, fact that may be attributed to the symmetrical distributions of the organs in relation to the radiation source. The results presented in this work showed that the computational exposure scenario provides a versatile and accurate tool to estimate in a ready way the absorbed doses during a cervical treatment.

    Palavras-Chave: absorbed radiation doses; animal tissues; computerized simulation; dosimetry; monte carlo method; organs; phantoms; radiotherapy; uterus

    Como referenciar este item
    Icon

  • IPEN-DOC 26784

    LITVAC, DANIEL ; CALDAS, LINDA V.E. . Calibration of a clinical beta therapy applicator using the thermoluminescence samples: preliminary results. In: CONGRESSO BRASILEIRO DE METROLOGIA, 10.; CONGRESSO INTERNACIONAL DE METROLOGIA ELÉTRICA, 13.; CONGRESSO INTERNACIONAL DE METROLOGIA MECÂNICA, 5.; CONGRESSO BRASILEIRO DE METROLOGIA DAS RADIAÇÕES IONIZANTES, 6.; WORKSHOP DA REDE DE METROLOGIA QUÍMICA DO INMETRO, 4.; CONGRESSO BRASILEIRO DE METROLOGIA ÓPTICA, 3., 24-27 de novembro, 2019, Florianópolis, SC. Anais... Rio de Janeiro, RJ: Sociedade Brasileira de Metrologia, 2019.

    Abstract: In some parts of Brazil, 90Sr/90Y clinical applicators are still used for dermatological and ophthalmic treatments, even with the higher efficiency of linear accelerators because they are of lower cost and easier use. Calibration and periodic recalibration of these applicators to verify the absorbed dose rate is essential to ensure accuracy in clinical treatments. In this work the thermoluminescent response of BeO and μLiF pellets was evaluated, determining the reproducibility, linearity of response and their dose-response curves. This standard, for this type of calibration, recommends the use of small detectors such as μLiF. Therefore, the utility of μLiF and BeO in the calibration of clinical applicators was compared.

    Palavras-Chave: beryllium oxides; lithium fluorides; beta particles; calibration; comparative evaluations; dosimetry; radiation sources; therapy; thermoluminescence

    Como referenciar este item
    Icon

A pesquisa no RD utiliza os recursos de busca da maioria das bases de dados. No entanto algumas dicas podem auxiliar para obter um resultado mais pertinente.

✔ É possível efetuar a busca de um autor ou um termo em todo o RD, por meio do Buscar no Repositório , isto é, o termo solicitado será localizado em qualquer campo do RD. No entanto esse tipo de pesquisa não é recomendada a não ser que se deseje um resultado amplo e generalizado.

✔ A pesquisa apresentará melhor resultado selecionando um dos filtros disponíveis em Navegar

✔ Os filtros disponíveis em Navegar tais como: Coleções, Ano de publicação, Títulos, Assuntos, Autores, Revista, Tipo de publicação são autoexplicativos. O filtro, Autores IPEN apresenta uma relação com os autores vinculados ao IPEN; o ID Autor IPEN diz respeito ao número único de identificação de cada autor constante no RD e sob o qual estão agrupados todos os seus trabalhos independente das variáveis do seu nome; Tipo de acesso diz respeito à acessibilidade do documento, isto é , sujeito as leis de direitos autorais, ID RT apresenta a relação dos relatórios técnicos, restritos para consulta das comunidades indicadas.

A opção Busca avançada utiliza os conectores da lógica boleana, é o melhor recurso para combinar chaves de busca e obter documentos relevantes à sua pesquisa, utilize os filtros apresentados na caixa de seleção para refinar o resultado de busca. Pode-se adicionar vários filtros a uma mesma busca.

Exemplo:

Buscar os artigos apresentados em um evento internacional de 2015, sobre loss of coolant, do autor Maprelian.

Autor: Maprelian

Título: loss of coolant

Tipo de publicação: Texto completo de evento

Ano de publicação: 2015

✔ Para indexação dos documentos é utilizado o Thesaurus do INIS, especializado na área nuclear e utilizado em todos os países membros da International Atomic Energy Agency – IAEA , por esse motivo, utilize os termos de busca de assunto em inglês; isto não exclui a busca livre por palavras, apenas o resultado pode não ser tão relevante ou pertinente.

✔ 95% do RD apresenta o texto completo do documento com livre acesso, para aqueles que apresentam o significa que e o documento está sujeito as leis de direitos autorais, solicita-se nesses casos contatar a Biblioteca do IPEN, bibl@ipen.br .

✔ Ao efetuar a busca por um autor o RD apresentará uma relação de todos os trabalhos depositados no RD. No lado direito da tela são apresentados os coautores com o número de trabalhos produzidos em conjunto bem como os assuntos abordados e os respectivos anos de publicação agrupados.

✔ O RD disponibiliza um quadro estatístico de produtividade, onde é possível visualizar o número dos trabalhos agrupados por tipo de coleção, a medida que estão sendo depositados no RD.

✔ Na página inicial nas referências são sinalizados todos os autores IPEN, ao clicar nesse símbolo será aberta uma nova página correspondente à aquele autor – trata-se da página do pesquisador.

✔ Na página do pesquisador, é possível verificar, as variações do nome, a relação de todos os trabalhos com texto completo bem como um quadro resumo numérico; há links para o Currículo Lattes e o Google Acadêmico ( quando esse for informado).

ATENÇÃO!

ESTE TEXTO "AJUDA" ESTÁ SUJEITO A ATUALIZAÇÕES CONSTANTES, A MEDIDA QUE NOVAS FUNCIONALIDADES E RECURSOS DE BUSCA FOREM SENDO DESENVOLVIDOS PELAS EQUIPES DA BIBLIOTECA E DA INFORMÁTICA.

O gerenciamento do Repositório está a cargo da Biblioteca do IPEN. Constam neste RI, até o presente momento 20.950 itens que tanto podem ser artigos de periódicos ou de eventos nacionais e internacionais, dissertações e teses, livros, capítulo de livros e relatórios técnicos. Para participar do RI-IPEN é necessário que pelo menos um dos autores tenha vínculo acadêmico ou funcional com o Instituto. Nesta primeira etapa de funcionamento do RI, a coleta das publicações é realizada periodicamente pela equipe da Biblioteca do IPEN, extraindo os dados das bases internacionais tais como a Web of Science, Scopus, INIS, SciElo além de verificar o Currículo Lattes. O RI-IPEN apresenta também um aspecto inovador no seu funcionamento. Por meio de metadados específicos ele está vinculado ao sistema de gerenciamento das atividades do Plano Diretor anual do IPEN (SIGEPI). Com o objetivo de fornecer dados numéricos para a elaboração dos indicadores da Produção Cientifica Institucional, disponibiliza uma tabela estatística registrando em tempo real a inserção de novos itens. Foi criado um metadado que contém um número único para cada integrante da comunidade científica do IPEN. Esse metadado se transformou em um filtro que ao ser acionado apresenta todos os trabalhos de um determinado autor independente das variáveis na forma de citação do seu nome.

A elaboração do projeto do RI do IPEN foi iniciado em novembro de 2013, colocado em operação interna em julho de 2014 e disponibilizado na Internet em junho de 2015. Utiliza o software livre Dspace, desenvolvido pelo Massachusetts Institute of Technology (MIT). Para descrição dos metadados adota o padrão Dublin Core. É compatível com o Protocolo de Arquivos Abertos (OAI) permitindo interoperabilidade com repositórios de âmbito nacional e internacional.

1. Portaria IPEN-CNEN/SP nº 387, que estabeleceu os princípios que nortearam a criação do RDI, clique aqui.


2. A experiência do Instituto de Pesquisas Energéticas e Nucleares (IPEN-CNEN/SP) na criação de um Repositório Digital Institucional – RDI, clique aqui.

O Repositório Digital do IPEN é um equipamento institucional de acesso aberto, criado com o objetivo de reunir, preservar, disponibilizar e conferir maior visibilidade à Produção Científica publicada pelo Instituto, desde sua criação em 1956.

Operando, inicialmente como uma base de dados referencial o Repositório foi disponibilizado na atual plataforma, em junho de 2015. No Repositório está disponível o acesso ao conteúdo digital de artigos de periódicos, eventos, nacionais e internacionais, livros, capítulos, dissertações, teses e relatórios técnicos.

A elaboração do projeto do RI do IPEN foi iniciado em novembro de 2013, colocado em operação interna em julho de 2014 e disponibilizado na Internet em junho de 2015. Utiliza o software livre Dspace, desenvolvido pelo Massachusetts Institute of Technology (MIT). Para descrição dos metadados adota o padrão Dublin Core. É compatível com o Protocolo de Arquivos Abertos (OAI) permitindo interoperabilidade com repositórios de âmbito nacional e internacional.

O gerenciamento do Repositório está a cargo da Biblioteca do IPEN. Constam neste RI, até o presente momento 20.950 itens que tanto podem ser artigos de periódicos ou de eventos nacionais e internacionais, dissertações e teses, livros, capítulo de livros e relatórios técnicos. Para participar do RI-IPEN é necessário que pelo menos um dos autores tenha vínculo acadêmico ou funcional com o Instituto. Nesta primeira etapa de funcionamento do RI, a coleta das publicações é realizada periodicamente pela equipe da Biblioteca do IPEN, extraindo os dados das bases internacionais tais como a Web of Science, Scopus, INIS, SciElo além de verificar o Currículo Lattes. O RI-IPEN apresenta também um aspecto inovador no seu funcionamento. Por meio de metadados específicos ele está vinculado ao sistema de gerenciamento das atividades do Plano Diretor anual do IPEN (SIGEPI). Com o objetivo de fornecer dados numéricos para a elaboração dos indicadores da Produção Cientifica Institucional, disponibiliza uma tabela estatística registrando em tempo real a inserção de novos itens. Foi criado um metadado que contém um número único para cada integrante da comunidade científica do IPEN. Esse metadado se transformou em um filtro que ao ser acionado apresenta todos os trabalhos de um determinado autor independente das variáveis na forma de citação do seu nome.