Reposiório IPEN: Recent submissions

  • IPEN-DOC 29686

    PEDREIRA FILHO, W.R.; PASSOS, J.S.; RUSCINC, N.; SILVA, M.L. da; MONTEIRO, L.R. ; COSTA, S.K.P.. Chemical safety knowledge assessment of academic researchers from Brazil during Covid-19 pandemic. International Journal of Occupational Safety and Health, v. 13, n. 2, p. 146-154, 2023. DOI: 10.3126/ijosh.v13i2.48904

    Abstract: Introduction: Laboratories are inextricably dangerous work environments, as fatal incidents are reported in both academic and non-academic environments worldwide, where poor safety culture has been recognized as the major accident contributor. Workers can be exposed to chemical, biological, physical, or radioactive hazards, in addition to musculoskeletal stresses. In Brazil, hundreds of thousands of workers are employed in laboratories, either in private or public institutions. Although laboratory safety can be governed by local, state, or federal regulations, learning how to identify common laboratory hazards is the first step to preventing accidents in the lab environment. Methods: The study aimed to assess the degree level of safety culture in an academic population of research laboratories, located in the largest city in Brazil, and their compliance with occupational safety regulations during the COVID-19 outbreak. This study was carried out between October and November 2020. The results were obtained from the standardized questionnaire used to assess 98 researchers working in laboratories during the COVID-19 pandemic. Results: The majority of respondents (95%) reported being exposed to more than two risks, simultaneously. About two-thirds (66%) of them were not fully aware of the laboratory's risk map. About half of the researchers (50%) were lacking in safety culture, and 57%and 43% were preoccupied with chemical and non-chemical hazards, respectively. Personal protective equipment (PPE) during laboratory work was used by most researchers, but 75% of researchers claim that security awareness learning should be a high priority for admission to laboratories. About 39% of researchers agreed that awareness of security must be improved in their laboratories Conclusion: The survey proves the lack of information and attitudes about chemical safety, especially among less experienced researchers, even if they use personal protective equipment when necessary.

    Palavras-Chave: hazards; laboratories; safety analysis; risk assessment; health hazards; chemical composition; occupational exposure; viruses

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  • IPEN-DOC 29685

    GALLO, JULIANA M.A.S.; SANTOS, ELAINE M.; GONCALVES, MARCELA L.L.; SOBRAL, ANA P.T.; RAIMUNDO, DANIELE; NASCIMENTO, ALANA R.; BUSSADORI, SANDRA K.; AZEVEDO, MILTON R.; SABATO, SUSY F. . Avaliação sensorial e pH de molhos para saladas tratados por radiação gama / Sensory evaluation and pH of salad dressings treated by gamma radiation. Research, Society and Development, v. 12, n. 2, p. 1-8, 2023. DOI: 10.33448/rsd-v12i2.39157

    Abstract: Avaliou-se as medida de pH de molhos para salada pronto para consumo com o objetivo de verificar sua estabilidade diante dos diferentes tratamentos com doses de radiação gama. Análises sensoriais, de dois dos molhos estudados foram conduzidas com o objetivo de avaliar a aceitação por consumidores diante da irradiação. de molhos comerciais para salada, tratados pelo processo de irradiação por raios gama, nas doses: 3 kGy e 5 kGy. Realizou-se o protocolo de estudo em duas fases. Na fase 1, as análises foram conduzidas logo após as amostras terem sido irradiadas, as quais se encontravam próximas a suas datas de fabricação. Na fase 2 as amostras foram reavaliadas após um período de armazenamento, próximo a data de expiração de suas validades. A irradiação, nas doses absorvidas estudadas, não influenciou o pH e os resultados da análise sensorial indicaram boa aceitação dos molhos irradiados pelos provadores.

    Palavras-Chave: food processing; irradiation; food; organic wastes; gamma radiation; taste buds

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  • IPEN-DOC 29684

    SCURO, N.L. ; ANGELO, G.; ANGELO, E.; PIRO, M.H.A.; UMBEHAUN, P.E. ; TORRES, W.M. ; ANDRADE, D.A. . Computational fluid dynamics analysis of an open-pool nuclear research reactor core for fluid flow optimization using a channel box. Nuclear Science and Engineering, v. 197, n. 6, p. 1100-1116, 2023. DOI: 10.1080/00295639.2022.2142437

    Abstract: A channel box installation in the IEA-R1 research reactor core was numerically investigated to increase fluid flow in fuel assemblies (FAs) and side water channels (SWCs) between FAs by minimizing bypasses in specific regions of the reactor core, which is expected to reduce temperatures and oxidation effects in lateral fuel plates (LFPs). To achieve this objective, an isothermal three-dimensional computational fluid dynamics model was created using Ansys CFX to analyze fluid flow distribution in the Brazilian IEA-R1 research reactor core. All regions of the core and realistic boundary conditions were considered, and a detailed mesh convergence study is presented. Results comparing both scenarios are presented in the percentage of use of the primary circuit pump. It is indicated that 21.4% of fluid bypass to unnecessary regions can be avoided with the channel box installation, which leads to the total mass flow from the primary circuit for all FAs increasing from 68.9% (without a channel box) to 77.6% (with a channel box). For the SWCs, responsible for cooling LFPs, an increment from 9.7% to 22.4%, avoiding all nondesired cross three-dimensional effects, was observed, resulting in a more homogeneous fluid flow and vertical velocities. It was concluded that the installation of a channel box numerically indicates an expressive mass flow increase and homogeneous fluid flow distribution for flow dynamics in relevant regions. This gives greater confidence to believe that lower temperatures, and consequently oxidation effects in LFPs, can be expected with a channel box installation.

    Palavras-Chave: computer codes; fluid mechanics; reactor cores; distribution; fluid flow

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  • IPEN-DOC 29683

    ESQUIVEL-HERNANDEZ, GERMAIN; MATIATOS, IOANNIS; SANCHEZ-MURILLO, RICARDO; VYSTAVNA, YULIYA; BALESTRINI, RAFFAELLA; WELLS, NAOMI S.; MONTEIRO, LUCILENA R. ; CHANTARA, SOMPORN; WALTERS, WENDELL; WASSENAAR, LEONARD I.. Nitrate isotopes (δ15N, δ18O) in precipitation: best practices from an international coordinated research project. Isotopes in Environmental and Health Studies, v. 59, n. 2, p. 127-141, 2023. DOI: 10.1080/10256016.2023.2177649

    Abstract: Stable isotope ratios of nitrogen and oxygen (15N/14N and 18O/16O) of nitrate (NO3–) are excellent tracers for developing systematic understanding of sources, conversions, and deposition of reactive atmospheric nitrogen (Nr) in the environment. Despite recent analytical advances, standardized sampling of NO3–) isotopes in precipitation is still lacking. To advance atmospheric studies on Nr species, we propose best-practice guidelines for accurate and precise sampling and analysis of NO3– isotopes in precipitation based on the experience obtained from an international research project coordinated by the International Atomic Energy Agency (IAEA). The precipitation sampling and preservation strategies yielded a good agreement between the NO3– concentrations measured at the laboratories of 16 countries and at the IAEA. Compared to conventional methods (e.g., bacterial denitrification), we confirmed the accurate performance of the lower cost Ti(III) reduction method for isotope analyses (15N and 18O) of NO3– in precipitation samples. These isotopic data depict different origins and oxidation pathways of inorganic nitrogen. This work emphasized the capability of NO3– isotopes to assess the origin and atmospheric oxidation of Nr and outlined a pathway to improve laboratory capability and expertise at a global scale. The incorporation of other isotopes like 17O in Nr is recommended in future studies.

    Palavras-Chave: nitrates; isotopes; nitrogen 15; geochemistry; oxygen 18; precipitation; inorganic compounds; regulatory guides; calibration standards

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  • IPEN-DOC 29682

    SILVA, REJANE M.P. da ; MILAGRE, MARIANA X. ; ARAUJO, JOAO V. de S. ; RAMIREZ, OSCAR M.P.; MACHADO, CARULINE de S.C. ; ANTUNES, RENATO A.; COSTA, ISOLDA . Investigação da atividade eletroquímica de liga Al-Cu-Li após processo de soldagem por fricção e mistura / Investigation of the electrochemical activity of an Al-Cu-Li alloy after friction stir welding process. Quimica Nova, v. 46, n. 4, p. 307-318, 2023. DOI: 10.21577/0100-4042.20230014

    Abstract: In this work, the local electrochemical activity of the zones coupled by Friction Stir Welding (FSW) of an Al-Cu-Li alloy was studied and the results were correlated to the microstructural characteristics of each zone. Electrochemical studies were carried out in the zones affected by welding using cyclic voltammetry (CV) and scanning electrochemical techniques (namely, SECM - Scanning Electrochemical Microscopy and LEIS – Local electrochemical impedance spectroscopy). The results showed that the welding joint (WJ) is predominantly cathodic relatively to the heat affected zones (HAZ). The HAZ was always anodic and showed the highest electrochemical activities among the tested ones. The high electrochemical activity of the HAZ was associated with the effect of galvanic coupling between the cathodic region (WJ) and the anodic region (HAZ). In addition, the advancing side (AS) presented increased electrochemical activity compared to the retreating one (RS).

    Palavras-Chave: friction welding; aluminium alloys; copper alloys; lithium alloys; electrochemistry

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  • IPEN-DOC 29681

    PRADO, E.S.P.; MIRANDA, F.S.; ARAUJO, L.G. de ; FERNANDES, G.L.; PEREIRA, A.L.J.; GOMES, M.C.; SILVA SOBRINHO, A.S. da; BALDAN, M.R.; PETRACONI, G.. Physicochemical modifications and decolorization of textile wastewater by ozonation: performance evaluation of a batch system. Ozone: Science and Engineering, v. 45, n. 3, p. 276-290, 2023. DOI: 10.1080/01919512.2022.2088470

    Abstract: This is an experimental study on the decolorization efficiency and the degradation of organic compounds from textile wastewater by the ozonation process in a batch system. The effects of different sample volumes of textile wastewater over time were investigated. The experiments were performed in a 1 L glass reactor with a magnetic stirrer and a bubble diffuser at the bottom to feed the ozone. The applied cumulative ozone dosage varied at 120 gO3 L−1, 60 gO3 L−1, and 30 gO3 L−1, and the total interaction time for each test was 1 h. To investigate the physicochemical properties of the textile wastewater (solid and liquid phases) before and after the treatment, multiple analytical characterization methods were used: Thermal Gravimetric Analysis, Scanning Electron Microscopy coupled with Energy-Dispersive X-ray Spectroscopy, X-ray diffraction, Fourier Transform Infrared spectroscopy, and Spectrophotometer. The most perceptive change was observed in the color of the liquid medium, which turned from black to transparent, and a visual color number indicator known as DurchsichtFarbZahl (DFZ) was used for the evaluation of this process. Absorbance values decreased about 3.5 times after 5 min of treatment with a 0.15 L sample volume, and these values differed for tests with larger sample volumes. FTIR spectroscopy demonstrated that the bands’ intensities associated with the C − H, C − N, and C − O decrease during treatment. On the other hand, it was possible to conclude that combining treatment methods to improve the degradation of persistent compounds after the ozonation process is necessary. Finally, the ozonation of the textile wastewater proved to be effective at removing color due to its high reaction capacity.

    Palavras-Chave: textile industry; waste water; ozonization; dyes; removal

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  • IPEN-DOC 29680

    SILVA, ARACELI J. ; ZAMBIAZI, PRISCILLA J. ; GOMES, PAULO V.R. ; NANDENHA, JULIO ; GODOI, CAMILA M. ; SOUZA, RODRIGO F.B. de ; NETO, ALMIR O. ; AZEREDO, NATHALIA F.B. . Conversão de metano em metanol com co-geração de energia elétrica a partir de catalisadores de paládio suportados em carbono / Conversion of methane to methanol with co-generation of electricity from palladium catalysts supported in carbon. Revista Virtual de Química, v. 15, n. 2, p. 221-226, 2023. DOI: 10.21577/1984-6835.20220101

    Abstract: The application of solid electrolyte reactors for methane oxidation and energy co-generation is attractive, especially with the use of catalysts synthesized from noble metals such as palladium. In this work, we prepared three different compositions of palladium on carbon support to evaluate the composition that had the greatest potential for energy generation. Catalysts in the proportions of 5, 10 and 20% of Pd/C were tested for the conversion of greenhouse gases into organic molecules of higher added value using electrochemical fuel cell solid electrolyte reactors. The focus of this work was the conversion of methane into methanol, using the fuel cell as a reactor and the commercial Pd/C as electrocatalyst. The electrocatalysts were tested at the anode, analyzed by infrared (IR) spectroscopy and their activities verified by experiments with rotating ring disk electrode (RRDE). Higher levels of palladium (Pd/C 20%) favored obtaining electrical power, and the intermediate composition (Pd/C 10%) showed a greater production of less oxidized compounds, such as methanol, in addition to generating electricity.

    Palavras-Chave: methane; oxidation; palladium; catalysts; fuel cells

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  • IPEN-DOC 29679

    VILLARDI, BRUNO D.Q. ; FILHO, NIVALDO G.P. ; GOMES, PAULO V.R. ; NANDENHA, JULIO ; GODOI, CAMILA M. ; TAGOMORI, THAIS L. ; AZEREDO, NATHALIA ; SOUZA, RODRIGO F.B. de ; NETO, ALMIR O. ; ZAMBIAZI, PRISCILLA J. . Desempenho eletrocatalítico de Pd/C e Pt/C para geração de energia a partir do extrato de cana-de-açúcar em célula a combustível de líquido direto / Electrocatalytic performance of Pd/C and Pt/C for power generation from sugarcane extract in direct liquid fuel cell. Revista Virtual de Química, v. 15, n. 2, p. 241-247, 2023. DOI: 10.21577/1984-6835.20220140

    Abstract: The processing of biomass to obtain fuels such as ethanol results in generating waste and polluting the environment. However, to meet energy demand and simultaneously reduce environmental pollution, fuel cells are promising devices for converting chemical compounds into electricity. Fuel cells can be powered by various types of liquids, including the sugars available in sugarcane extract, with high energy potential. Fuel cells employ the use of noble metals as electrocatalysts, such as Pt or Pd, to carry out the oxidation of these fuels. In this sense, this work reports the study of the oxidation of sugarcane extract in these different noble metals. The platinum catalyst was shown to be more active for the oxidation of sugars, resulting in a power density 10 times greater than Pd/C using a 50% diluted sugarcane extract solution, resulting in promising fuel cell systems. To produce ecologically correct electrical energy for the industry in general.

    Palavras-Chave: biomass; sugar cane; renewable energy sources; electrocatalysts; fuel cells

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  • IPEN-DOC 29678

    GROSSI, DANIELLE; LAZAR, DOLORES R.R. ; DEL LAMA, ELIANE A.; USSUI, VALTER . Titania-silica composite with photocatalytic properties and its application on Brazilian granite and sandstone. International Journal of Architectural Heritage, v. 17, n. 5, p. 770-787, 2023. DOI: 10.1080/15583058.2021.1969483

    Abstract: The aim of the study described in this article was to evaluate a product containing titania (titanium dioxide, TiO2) applied on stones — particularly two types used at Brazilian stone-built heritage sites — that have been exposed to weathering and anthropogenic activities. This product was prepared by producing a suspension of TiO2 at two concentrations (1% and 4% w/v) with tetraethyl orthosilicate (TEOS) in the presence of n-octylamine as surfactant. The characteristics of the TiO2 were then observed by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) surface-area measurements, particle-size distribution analysis (CILAS) and X-ray diffraction. After applying the TiO2-TEOS composite, the stones were examined for contact angle, spectrophotometry, sorptivity, thermal shock resistance, and UV-radiation resistance. The product proved ineffective on Itararé sandstone, mainly due to its mineralogical components, as the product does not adhere to quartz. When applied on Itaquera granite, the 1% TiO2 (w/v) concentration proved to be an appropriate treatment, as it demonstrated better thermal shock resistance, photocatalytic activity, porosity maintenance, and global colour when compared to the 4% concentration.

    Palavras-Chave: architecture; cultural resources; photocatalysis; sandstones; composite materials; titanium oxides

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  • IPEN-DOC 29677

    MORALES, J.M.G.; TORTAMANO-NETO, P.; TODESCAN, F.F.; ANDRADE JUNIOR, J.C.S. de; MAROTTI, J.; ZEZELL, D.M. . Resonance frequency analysis of dental implants after laser therapy. Clinical Oral Implants Research, v. 21, n. 10, p. 1045-1045, 2010. DOI: 10.1111/j.1600-0501.2010.01994.x

    Abstract: Background: The importance of primary stability in implant placement for long-term success is well known in the literature. The resonance frequency analysis technique has extensively been used in experimental and clinical research for the last 10 years, for assessing primary stability. The benefits of low-level laser therapy in bone tissue are already consolidated in the literature, however, little is known about its benefits on improvement of stability of dental implants. Aim: The aim of this randomdouble blind clinical study was to investigate whether stability of titanium implants can be enhanced by low-level laser therapy during the osseointegration process when measured by means of resonance frequency analysis. Methods: Thirty implants (n¼30) were placed in the posterior region of partially edentulous mandible of eight adult patients, after following several inclusion criteria and were distributed bilaterally in agreement with the prosthetic requirement. The implants on the experimental side were randomly submitted to low-level laser therapy (830 nm, 86mW, 92.1 J/cm2, 2.57 J, 3 s/ point, at 20 points), and on the control side the laser irradiation was only simulated. The first irradiation was performed in the immediate postoperative period, and it was repeated every 48 h in the first 14 days. The initial implant stability quotient of the implants was measured by means of resonance frequency analyzer (Osstells). New implant stability quotient measurements were made after 10 days, 3, 6, 9 and 12 weeks. ANOVA for repeated measurements and Bonferroni test were used to assess statistically significant differences. Results: The initial implant stability quotient values ranged from 65 to 84, with a mean of 76. The irradiated side showed significant drop in stability from the 10th day until the sixth week only (P¼0.028), and presenting a gradual increase from the sixth to the 12th week. In the control side, the mean implant stability quotient increased up to the third week, decreased in the sixth week, and then began to grow again. The highest stability values were observed in the 10th day in the irradiated group, and the lowest in the sixth week in both groups. No statistical differences were detected among the ISQ means in the two groups for each of the six times observation. Conclusions and clinical implications: No evidence was found of any effect of low-level laser therapy on implants’ stability when measured by resonance frequency analysis. Because high primary stability and good bone quality are of major relevancy for a rigid bone–implant interface, additional low-level laser therapy under these conditions may have little impact macroscopically. Further researches under different bone conditions are necessary for a better understanding of the occurrences at bone/implant interface.

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  • IPEN-DOC 29676

    ANA, P.A. ; TABCHOURY, C.P.M.; CURY, J.A.; ZEZELL, D.M. . Effect of Er,Cr:YSGG laser and fluoride application on enamel demineralization. Caries Research, v. 41, n. 4, p. 325-326, 2007. DOI: 10.1159/000103637

    Abstract: This study evaluated the influence of sub-ablative Er,Cr:YSGG laser and topical fluoride application on incipient caries development in vitro. One hundred and sixty human enamel slabs were ramdomly divided into eight equal groups: (1) untreated (control); (2–4) irradiated with Er,Cr:YSGG laser at 0.25, 0.50 and 0.75 W, respectively; (5) treated with acidulated phosphate fluoride (APF; 1.23% F) for 4 min; (6–8) pre-irradiated with Er,Cr:YSGG laser at 0.25, 0.50 and 0.75 W, respectively and subjected to APF application. All groups were submitted to pH-cycling simulating a cariogenic challenge, and after 10 cycles mineral loss ( Δ Z) was measured in enamel. Calcium, inorganic phosphorus (P i ) and fluoride concentrations were also measured in the demineralizing and remineralizing pH-cycling solutions. Data were analyzed by ANOVA ( α = 0.05). No differences in Δ Z were found between laser irradiation at 0.25 W, 0.50 W and controls, while after laser irradiation at 0.75 W (Group 4) and application of APF (Group 5) there was a significant decrease in Δ Z. Laser irradiation at 0.50 and 0.75 W prior to APF application there was a significantly lower Δ Z than in other groups. A significant increase in Ca and P i concentrations was observed in demineralizing solutions compared to the initial concentrations, but no significant changes in Ca and P i concentrations were detected between any groups. A significant decrease in fluoride concentration was observed in pH-cycling solutions of control and 0.25 W laser groups, while the association of laser at 0.50 and 0.75 W with fluoride promoted an increase of fluoride content in remineralizing solutions. In conclusion, Er,Cr:YSGG laser irradiation at 0.50 and 0.75 W, associated with fluoride, seems to be a good alternative for reducing enamel demineralization.

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  • IPEN-DOC 29675

    ESTEVES-OLIVEIRA, M.; ZEZELL, D.M. ; VELLOSO, W.F.; MEISTER, J.; FRANZEN, R.; LAMPERT, F.; EDUARDO, C.P.; APEL, C.. Low fluence CO2 laser (10.6 μm) parameters for caries prevention. Caries Research, v. 41, n. 4, p. 325-325, 2007. DOI: 10.1159/000103637

    Abstract: Although CO 2 laser irradiation can decrease enamel demineralization, thermal damage to the surface is a common side effect. The occurrence of fissures and cracks may compromise in vivo application. Therefore, the aim of the present study was to find CO 2 laser (10.6 μm) parameters resulting in maximum caries- preventive effect with the lowest thermal damage. Five low fluences of 0.12, 0.29, 0.39, 0.50 and 0.60 J/cm 2 combined with high repetition rates of 500, 154, 167, 182, 187 Hz, respectively and 10 μs pulse duration were chosen for the experiments. 78 bovine enamel cubes were divided into 5 laser groups and one control. After treatment the samples were submitted to an 8-day pH-cycling regime. Demineralization was assessed by lesion depth measurements with a polarized-light microscope. The temperature rise at the enamel surface and the propagation into deeper layers were calculated using a finite element model. Surface morphology was evaluated by SEM. All laser groups resulted in statistically significant lower lesion depths than the control group (ANOVA; p < 0.05). Morphologically, the two lowest fluences resulted in no surface changes. The calculated temperature rise at 1.5 mm depth was less than 5 ° C in all groups. In the present in vitro study irradiation with 0.12 J/cm 2 , 500 Hz and 2500 pulses of CO 2 laser increased enamel caries resistance without causing undesirable surface damage or excessive temperature rise.

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  • IPEN-DOC 29674

    FREJLICH, JAIME; VIANNA, SANDRA; DAVIDOVICH, LUIZ; KHOURY, ANTONIO Z.; WETTER, NIKLAUS U. . Ótica e Fotônica. In: NOGUEIRA, SALVADOR (Org.); ROMERO, THIAGO (Org.). Física 2011: estado da arte, desafios e perspectivas para os próximos cinco anos. São Paulo, SP: Chris McHilliard Editora, 2011. p. 127-133,

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  • IPEN-DOC 29673

    BAFFA FILHO, OSWALDO; ZEZELL, DENISE M. ; COSTA, PAULO R.; SILVA, ANA M.M. da; FREITAS, MARCELO B. de. Física Médica. In: NOGUEIRA, SALVADOR (Org.); ROMERO, THIAGO (Org.). Física 2011: estado da arte, desafios e perspectivas para os próximos cinco anos. São Paulo, SP: Chris McHilliard Editora, 2011. p. 83-97,

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  • IPEN-DOC 29672

    EDUARDO, FERNANDA P.; MEHNERT, DOLORES U.; MONEZI, TELMA A.; ZEZELL, DENISE M. ; SCHUBERT, MARK M.; EDUARDO, CARLOS P.; MARQUES, MARCIA M.. In vitro effect of phototherapy with low intensity laser on HSV-1 and epithelial cells. In: HAMBLIN, MICHAEL R. (Ed.); WAYNANT, RONALD W. (Ed.); ANDERS, JUANITA (Ed.) SPIE BIOS, January 20-25, 2007, San Jose, CA, USA. Proceedings... Bellingham, WA, USA: SPIE, 2007. p. 642805-1 - 642805-10. (Proceedings SPIE 6428, Mechanisms for Low-Light Therapy II, 642805). DOI: 10.1117/12.700682

    Abstract: The effects of phototherapy on herpes lesions have been clinically demonstrated by either preventing the lesion formation or speeding their repair. The aim of this in vitro study was analyze the effect of phototherapy on epithelial cells and HSV-1 in culture. Cultures of HSV-1 and epithelial cells (Vero cell line) were used. The irradiations were done using a GaAlAs laser (660 e 780 nm, 4.0 mm2). One, two and three irradiations with 6 h-intervals were done. The experimental groups were: Control: non-irradiated; 660 nm and 3 J/cm2 (2.8 sec); 660 nm and 5 J/cm2 (3.8 sec); 780 nm and 3 J/cm2 (1.9 sec), and 780 nm and 5 J/cm2 (2.5 sec). The HSV-1 cytopatic effect and the cell viability of irradiated cultures and controls were analyzed in four different conditions: irradiation of non-infected epithelial cells; epithelial cells irradiated prior infection; virus irradiated prior infection; irradiation of HSV infected cells. The mitochondrial activity and cytopathic effects were assessed. The number of irradiations influenced the cell growth positively and proportionally, except for the 660 nm/ 3 J/cm2 group. Any variation in cytopathic effects was observed amongst the experimental groups. The viability of infected cells prior irradiation was significantly higher than that of non-irradiated cultures when 2 irradiations were done. Under the experimental conditions of this study we concluded that phototherapy is capable of enhancing epithelial cell growth and prolonging cell viability of HSV-1 infected cells. Positive benefits of phototherapy could be resultant from prolongation of infected cells viability, corroborating with host defenses.

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  • IPEN-DOC 29671

    MIYAKAWA, WALTER; MASSI, MARCOS; RABELO NETO, JOSE da S. ; ZEZELL, DENISE M. . Caracterização de hidroxiapatita sintética por microscopia de força atômica. In: ENCONTRO NACIONAL DE FISICA DA MATERIA CONDENSADA, 31., 5-9 de maio, 2008, Águas de Lindóia, SP. Resumo... 2008.

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  • IPEN-DOC 29670

    ARAUJO, R.E. de; MELO, L.S.A. de; FREITAS, A.Z. ; ZEZELL, D. ; VIEIRA JUNIOR, N.D. ; GOMES, A.S.L.. Applying optical coherence tomography in dental restoration. In: SBMO/IEEE MTT-S INTERNATIONAL MICROWAVE AND OPTOELECTRONIC CONFERENCE, July 25-28, 2005, Brasília, DF. Proceedings... Piscataway, NJ, USA: IEEE, 2005. p. 411-414. DOI: 10.1109/IMOC.2005.1580032

    Abstract: Optical coherence tomography was use to perform an evaluation of molar dental restorations. Imaging resolution of 10 /spl mu/m is achieved and dental cavities small as 50 /spl mu/m are measured. OCT images were compared with X-ray and optical microscopy pictures.

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  • IPEN-DOC 29669

    LOPEZ, MARCIO A.P.A. ; BERECZKI, ALLAN ; WETTER, NIKLAUS U. . Nd:YAG polarized laser with beam quality beyond the birefringence limit and its application in a Singly-Resonant Optical Parametric Oscillator. In: SÃO PAULO SCHOOL OF ADVANCED SCIENCE ON FRONTIERS IN LASERS AND THEIR APPLICATIONS; JORGE ANDRÉ SWIECA SCHOOL ON NON LINEAR AND QUANTUM OPTICS, 16th, July 16-27, 2018, São Paulo, SP. Poster... 2018.

    Abstract: We demonstrate a simple, reliable and cheap high output power, linearly polarized and high-quality beam @1064 nm laser source, based on a previous work [i], where a Nd:YAG Diode-pumped Solid-state Laser (DPSSL) based on standard, commercial laser modules was presented. This kind of laser source is interesting for a large number of applications, such as pump laser for an Optical Parametric Oscillator (OPO) and frequency conversion, maintaining near-diffraction-limited beam quality factor (M2~1).

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  • IPEN-DOC 29668

    WETTER, N.U. . Neodymium doped lithium yttrium fluoride (Nd:YLiF4) lasers. In: DENKER, B. (Ed.); SHKLOVSKY, E. (Ed.). Handbook of solid-state lasers: Materials, systems and applications. Cambridge, UK: Woodhead Publishing, 2013. p. 323-340, cap. 12. (Woodhead Publishing Series in Electronic and Optical Materials, 35). DOI: 10.1533/9780857097507.2.323

    Abstract: As a laser material, the neodymium doped lithium yttrium fluoride laser shows some very important and favorable characteristics when it comes to laser beam quality, efficient high-energy pulsed operation and parametric processes, amongst other applications. In this chapter we will discuss several approaches that have resulted in efficient, high-quality laser beams usually through decreasing the influence of the structural drawbacks of the YLF host whilst taking advantage of its favorable optical properties.

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  • IPEN-DOC 29667

    CAMARGO, F. ; ZANON-WILLETTE, T.; BADR, T.; WETTER, N.U. ; ZONDY, J.-J.. 620 mW single-frequency Nd:YVO4/BiB3O6 red laser. In: CONFERENCE ON LASERS AND ELECTRO-OPTICS; INTERNATIONAL QUANTUM ELECTRONICS CONFERENCE, June 2-4, 2009, Baltimore, MD, USA. Proceedings... Washington, DC, USA: Optical Society of America, 2009.

    Abstract: Using a type-I critically phase-matched bismuth borate crystal, a record 620 mW single-frequency red laser at 671 nm is achieved from intra-cavity SHG of a pi-polarized single-end pumped Nd:YVO 4 ring laser oscillating on the lambda~1342 nm transition.

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  • IPEN-DOC 29666

    CAMARGO, F. ; ZANON-WILLETTE, T.; SARROUF, R.; BADR, T.; WETTER, N.U. ; ZONDY, J.-J.. 1.3 Watt Single-Frequency Nd:YLF/ppKTP red laser. In: CONFERENCE ON LASERS AND ELECTRO-OPTICS; INTERNATIONAL QUANTUM ELECTRONICS CONFERENCE, June 2-4, 2009, Baltimore, MD, USA. Proceedings... Washington, DC, USA: Optical Society of America, 2009. DOI: 10.1364/CLEO.2009.CThZ7

    Abstract: Using a temperature-tuned ppKTP crystal, a record 1.3 W single-frequency red laser at 661 nm is achieved from intra-cavity second-harmonic generation of a Nd:YLiF 4 ring laser oscillating on the pi-polarized transition (lambda~1321 nm).

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  • IPEN-DOC 29665

    WETTER, NIKLAUS ; FREJLICH, JAIME. Editorial. Selected Papers from RIAO/OPTILAS 2007 (Campinas, São Paulo, Brazil, 21-26 October 2007). Journal of Optics A: Pure and Applied Optics, v. 10, n. 10, p. 1-1, 2008. DOI: 10.1088/1464-4258/10/10/100201

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  • IPEN-DOC 29664

    MATOS, P.S.F. de ; WETTER, N.U. . Optimization of a 2.3 µm Yb:Tm:YLF laser, pumped at 685 nm and 960 nm simultaneously. In: ENCONTRO NACIONAL DE FISICA DA MATERIA CONDENSADA, 29., 9-13 de maio, 2006, São Lourenço, MG. Anais... São Paulo, SP: Sociedade Brasileira de Física, 2006.

    Abstract: For the first time, a unique pumping scheme for the thulium 2.3 micrometer transition is proposed that is capable of enhancing the output power by almost a factor three when compared to the traditional pumping scheme at 960 nm. The best relation between 685 nm pump power and 960 nm pump power is shown. The achieved output power of 620 mW is the highest reported so far.

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  • IPEN-DOC 29663

    WETTER, NIKLAUS U. . Bandwidth narrowing and dual wavelength emission of a 20 W laser diode array. In: ENCONTRO NACIONAL DE FISICA DA MATERIA CONDENSADA, 29., 9-13 de maio, 2006, São Lourenço, MG. Anais... São Paulo, SP: Sociedade Brasileira de Física, 2006.

    Abstract: We report on the performance of a commercial, non-AR coated diode laser bar, consisting of 20 emitters, which uses an external cavity to achieve 16 W of bandwidth-narrowed output and 2.9 W of dual wavelength emission. These are the highest output powers reported so far for this type of cavity and diode laser array.

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  • IPEN-DOC 29662

    FRACASSO, PAULO T.; NADER, GILDER; JABARDO, PAULO J.S.; PEREIRA, MARCOS T.; CALY, JOSE P.; BRUNA, WAGNER C.; MARTINS, FLAVIUS P.R.; FERRARA, EDUARDO; MURAMATSU, MIKIYA; WETTER, NIKLAUS U. . Development of a PIV system using a laser-diode. In: INTERNATIONAL CONGRESS OF MECHANICAL ENGINEERING, 18th, November 6-11, 2005, Ouro Preto, MG. Proceedings... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas - ABCM, 2005.

    Abstract: A low cost PIV (Particle Image Velocimetry) was developed for characterization, visualization and quantification of a flow test section. Optical devices are common nowadays in metrology, in fluid-flow measurement and studies of flow around structural models or industrial facilities in wind tunnels. The advantages of the optic devices are high resolution, precision, fast response time and, most important, it is not intrusive. The PIV system developed is composed by a quasi-continuous laser-diode with nominal power up to 100 W, monochromatic at 800 nm wave length. An orthogonal lens set defines the width and thickness of the light screen in the test section. Image acquisition is made by a CCD camera. Acquisition and processing image software was developed in C++ and Matlab. The flow field velocities are determined by processing successive images using cross correlation. Analysis of fluid flow around 1 and 2 cylinders, in parallel, were conducted. The tests were conducted in water seeded with micro-spheres with 30 μm mean diameter. The analysis were conducted with velocities of the order of 0.15 m/s, the optical window dimensions was about 100 mm x 150 mm. The results show that the PIV prototype is working even though further development is necessary.

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  • IPEN-DOC 29661

    WETTER, NIKLAUS U. ; CAMARGO, FABIOLA de A. ; RANIERI, IZILDA M. ; BALDOCHI, SONIA L. ; LANDULFO, EDUARDO . Side-pumped, high beam-quality Nd:YLF amplifier for LIDAR applications. In: CONFERENCE ON LASERS AND ELECTRO-OPTICS EUROPE, June 12-17, 2005, Munich, Germany. Abstract... Piscataway, NJ, USA: IEEE, 2005. p. 53-53.

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  • IPEN-DOC 29660

    COURROL, LILIA C.; KASSAB, LUCIANA R.P.; DEL CACHO, VANESSA; WETTER, NIKLAUS U. ; GOMES, LAERCIO ; VIEIRA JUNIOR, NILSON D. ; MESSADDEQ, YOUNES; RIBEIRO, SIDNEY J.L.. Study of neodymium laser transition in glasses and influence of up-conversion processes under diode pumping. In: CONFERENCE ON LASERS AND ELECTRO-OPTICS EUROPE, June 22-27, 2003, Munich, Germany. Abstract... Piscataway, NJ, USA: IEEE, 2003. p. 406-407.

    Abstract: By solving the rate equations including upconversion for Nd glass hosts under continuous diode pumping, it was possible to calculate the nonlinear behavior of the pumping efficiency and threshold pump intensity as a function of exited-state population.

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  • IPEN-DOC 29659

    FUKUMOTO, MARCOS E.; WETTER, NIKLAUS U. ; KASSAB, LUCIANA R.P.; COURROL, LILIA C.. Optimum Yb3+ concentration in PbO-Bi2O3-Ga2O3 glasses for ultrashort laser applications. In: CONFERENCE ON LASERS AND ELECTRO-OPTICS EUROPE, June 22-27, 2003, Munich, Germany. Abstract... Piscataway, NJ, USA: IEEE, 2003. p. 404-405.

    Abstract: This study examines different Yb3+ doping levels in heavy metal oxide glasses showing interesting properties for laser applications at 1012 nm, mainly for short pulse generation under diode pumping.

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  • IPEN-DOC 29658

    AMANCIO, CARLOS T.; JAKUTIS NETO, JONAS ; WETTER, NIKLAUS U. ; BONFIM JÚNIOR, FRANCISCO A. ; KASSAB, LUCIANA R.P.. Estudo do mecanismo de conversão ascendente no visível em vidros de telureto codopados com Er3+ e Yb3+. Boletim Técnico da Faculdade de Tecnologia de São Paulo, v. 23, 2007.

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  • IPEN-DOC 29657

    ASSUMPCAO, THIAGO A.A. de; JAKUTIS NETO, JONAS ; WETTER, NIKLAUS U. ; KASSAB, LUCIANA R.P.. Emissão de luz azul em amostras de germanato dopadas com Tm:Yb e Tm:Yb:Nd. Boletim Técnico da Faculdade de Tecnologia de São Paulo, v. 21, 2006.

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  • IPEN-DOC 29656

    LIMA, B.L.S. de; COURROL, L.C.; KASSAB, L.R.P.; DEL CACHO, V.D.; GOMES, L. ; WETTER, N.U. . Estudo de processos de conversão ascendente em vidros dopados com Nd3+. Boletim Técnico da Faculdade de Tecnologia de São Paulo, v. 15, p. 51-51, 2003.

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  • IPEN-DOC 29655

    DEL CACHO, VANESSA D.; KASSAB, LUCIANA R.P.; COURROL, LILIA C.; WETTER, NIKLAUS U. . Propriedades espectroscópicas de vidros de fluorborato de chumbo dopados com Nd3+ para uso em laser de estado sólido. Boletim Técnico da Faculdade de Tecnologia de São Paulo, v. 13, p. 27-27, 2002.

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  • IPEN-DOC 29654

    COURROL, LILIA C.; KASSAB, LUCIANA R.P.; FUKUMOTO, MARCOS E.; GOMES, LAERCIO ; WETTER, NIKLAUS U. ; VIEIRA JUNIOR, NILSON D. ; CASSANJES, FABIA C.; MESSADDEQ, YOUNES; RIBEIRO, SIDNEY J.L.. Evaluation of the most suitable new glass laser medium to incorporate Ytterbium: Alkali Niobium Tellurite, Lead Fluorborate or Heavy Metal Oxide. Boletim Técnico da Faculdade de Tecnologia de São Paulo, v. 12, 2002.

    Abstract: The most important advantage of Ytterbium compared to others dopants such as Neodymium is its broadband emission nature, which is very suitable for both tunable and ultrafast lasers. In this paper we present the study and characterization of three different glass families: Alkali Niobium Tellurite, Lead Fluoroborate and of Heavy Metal Oxides, all prepared containing Ytterbium. The Ytterbium (Yb) emission spectrum in Tellurite glass samples was obtained by excitation into the absorption peak at 975 nm. The Yb peak emission cross-section was calculated using the fluorescence lineshape, the radiative lifetime (0.59 ms) and the refractive index 2.09. With these values we found the emission cross-section of Yb in Tellurite glass doped. Lead Fluorborate glasses have high refractive index of 2.2, and an absorption band centered at 968nm. The spontaneous emission probability was calculated and we determined that it decreases with the increase of Yb concentration. The same applies for the fluorescence lifetime and to the emission cross-section. We measured the fluorescence lifetime of 0.81ms, and an emission band at 1022nm with an effective emission linewidth of 60nm. Heavy metal oxide glass also has high refractive index (2.5) and transmission cutoff of about 8mm. In this glass the fluorescence effective linewidth was 86nm and radiative lifetime 300 ms. Calculations of the minimum pump intensity are also presented. A comparison of laser properties of these three different glasses and their importance is shown and analyzed.

    Palavras-Chave: ytterbium; glass; niobium tellurides; fluoroborates; heavy metals; oxides; fluorescence

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  • IPEN-DOC 29653

    MENZEL, SILVIO C. . Proposta de adequação das instalações de infraestrutura – Sala de Equipamentos de Informática do CPD/ SEGRS – alimentação para equalização dos no breaks de 20 KVA – critérios de instalação elétrica e infraestrutura definitiva – relatório final. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEENG, Abril, 2023. (IPEN-CEN-PSE-SEGRS-001-00-RELT-006-00). Restrito.

    Título do projeto: Prestação de Serviços Tecnológicos (Estruturação do Laboratório Multiusuário de Computação Científica do DIPEN)

    Abstract: Apresentar uma proposta de adequação das instalações de infraestrutura da sala de equipamentos de informática do setor de Gestão de Redes e Suporte Técnico, SEGRS, com o objetivo da implantação do Laboratório Multiusuário de Computação Científica, LMCC, dentro da área do Instituto de Pesquisas Energéticas e Nucleares, IPEN, localizado na Av. Professor Lineu Prestes, 2.242, Portaria Sul, Butantã, na Cidade Universitária "Armando de Salles Oliveira”, CEP 05508-000, Cidade de São Paulo – SP. Este será o último relatório, para fechamento da tarefa No IPEN-CEN-PSE-SEGRS-001-00, que abordará as adequações executadas e não executadas descritas nos 2 (dois) relatórios anteriores, denominados de RELT-001 e RELT 002, além de descrever as medidas necessárias para a equalização dos novos No Breaks de 20 kVA e apresentar os requisitos para a instalação elétrica e de infraestrutura definitiva.

    Palavras-Chave: equipment; laboratories; laboratory equipment; data analysis; electrical equipment

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  • IPEN-DOC 29652

    BITELLI, ULYSSES D. . Comissionamento: obtenção experimental da curva de calibração e da reatividade integral das barras de controle do reator IPEN/MB-01 – núcleo contendo elementos combustíveis tipo placa. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEENG, Abril, 2023. (IPEN-CEN-PSE-RMB-005-00-RELT-123-00). Restrito.

    Título do projeto: Prestação de Serviços Tecnológicos

    Abstract: Este relatório apresenta o procedimento experimental [1] e os resultados obtidos para calibração das quatro barras de controle do novo núcleo do Reator IPEN/MB-01 [2] contendo elementos combustíveis tipo placa, correlacionando reatividade com o trecho de barra retirado ou inserido no núcleo (reatividade diferencial) e, por conseguinte, obtendo a reatividade total inserida (valor integral das barras de controle), através do somatório dos valores diferenciais de reatividade. Os valores de reatividade integral das quatro barras de controle de háfnio do núcleo contendo elementos combustíveis tipo placa obtidos experimentalmente são dados a seguir. BC#1 = (3371,99 ± 34,38) pcm, BC#2 = (3780,89 ± 39,41) pcm, BC#3 = (3309,78 ± 32,18) pcm, BC#4 = (3771,08 ± 37,52) pcm. As curvas ajustadas de calibração das barras de controle podem ser vistas nos apêndices para as quatro barras de controle e foram obtidas através do ajuste [3] da equação de Boltzmann dada abaixo aos valores diferencias de reatividade obtidos para cada trecho de barra retirado/inserido. y=A2+(A1-A2)/(1+e^((x-x0)/dx)). Os coeficientes da Equação de Boltzmann são dados na Tabela 1.

    Palavras-Chave: commissioning; reactor commissioning; control elements; fuel plates; reactivity

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  • IPEN-DOC 29651

    TORRES, WALMIR M. . Adequação das unidades da Torre de Resfriamento A do IEA-R1 para aumento da capacidade de troca de calor. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEENG, Abril, 2023. (IPEN-CEN-PSE-IEAR1-146-00-INFT-001-00). Restrito.

    Título do projeto: Prestação de Serviços Tecnológicos

    Palavras-Chave: cooling towers; iear-1 reactor; heat exchangers; measuring instruments; anemometers; velocity

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  • IPEN-DOC 29650

    SHORTO, JULIAN M.B. ; CARLUCCIO, THIAGO . Estimativas dos fluxos de nêutrons e gamas e doses por radiação direta em acidentes de criticalidade no CECON do IPEN para subsidiar o posicionamento dos detetores do Sistema de Alarme de Acidente de Criticalidade. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEENG, Abril, 2023. (IPEN-CEN-PSE-CCN-011-00-RELT-001-00). Restrito.

    Título do projeto: Prestação de Serviços Tecnológicos (Sistema de Alarme de Acidente de Criticalidade – CECON)

    Abstract: Este trabalho visa estimar o fluxo de nêutrons, o fluxo de gamas e as doses absorvidas esperadas por radiação direta instantânea em acidentes de criticalidade no Centro do Combustível Nuclear (CECON/IPEN) de forma a subsidiar o posicionamento dos detetores do Sistema de Alarme de Acidente de Criticalidade. O CECON é responsável pela produção do combustível nuclear para a operação do reator de pesquisa IEA-R1, situado no IPEN.

    Palavras-Chave: criticality; radiation accidents; neutron flux; nuclear fuels; reactors; alarm systems

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  • IPEN-DOC 29649

    YAMAGUCHI, MITSUO . Análise de criticalidade do Cofre de Salvaguardas (Sala 36) do Prédio 97 do Centro do Combustível Nuclear (CECON). São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEENG, Abril, 2023. (IPEN-CEN-PSE-CCN-007-00-RELT-003-00). Restrito.

    Título do projeto: Prestação de Serviços Tecnológicos (Análise de Criticalidade do Cofre de Salvaguardas – CECON)

    Abstract: Este relatório apresenta a análise de criticalidade do cofre de salvaguardas (sala 36 do prédio 97) do Centro de Combustível Nuclear (CECON) para armazenamento de placas combustíveis e/ou elementos combustíveis do núcleo do Reator IEA-R1. A análise foi feita com o sistema SCALE4.4a.

    Palavras-Chave: criticality; nuclear fuels; safeguards; fuel elements

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  • IPEN-DOC 29648

    YAMAGUCHI, MITSUO . Análise de criticalidade do Cofre de Salvaguardas (Sala 22) do Prédio 96 do Centro do Combustível Nuclear. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEENG, Abril, 2023. (IPEN-CEN-PSE-CCN-007-00-RELT-002-00). Restrito.

    Título do projeto: Prestação de Serviços Tecnológicos (Análise de Criticalidade do Cofre de Salvaguardas – CECON)

    Abstract: Este relatório apresenta a análise de criticalidade do cofre de salvaguardas (sala 22 do prédio 96) do Centro de Combustível Nuclear (CECON). A análise foi feita com o sistema SCALE4.4a.

    Palavras-Chave: criticality; nuclear fuels; safeguards; fuel elements

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  • IPEN-DOC 29647

    TADDEI, MARIA H.T. ; TERREMOTO, LUIS A.A. . Resultados e proposição preliminar de fatores de escala ou funções de correlação do concentrado de evaporador de Angra 1. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEENG, Abril, 2023. (IPEN-CEN-P&D-ETN-218-01-RELT-006-00). Restrito.

    Título do projeto: Composição Isotópica dos Rejeitos Radioativos da CNAAA

    Abstract: Este documento tem como objetivo analisar os resultados das análises radioquímicas das amostras de concentrado de evaporador de Angra 1 obtidos até o momento e avaliar a existência de fatores de escala ou funções de correlação que possam ser usados na caracterização isotópica desta matriz de rejeitos. Apresentam-se os valores preliminares dos parâmetros associados. O presente relatório técnico foi elaborado em atendimento ao item 8.3.2 , “Determinação dos fatores de escala e/ou correlações quando possível, incluindo cálculo de fatores de escala existentes”) do Plano de trabalho anexo ao Acordo “Determinação da Composição Isotópica dos Rejeitos Radioativos da CNAAA (Fase B)”, do ACORDO DE PARCERIA TECNOLÓGICA firmado entre a ELETROBRÁS TERMONUCLEAR S.A., a CNEN - COMISSÃO NACIONAL DE ENERGIA NUCLEAR e a FUNDEP – Fundação de Desenvolvimento da Pesquisa.

    Palavras-Chave: radioactive wastes; evaporators; scale models; radioisotopes; radiochemical analysis

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  • IPEN-DOC 29646

    TADDEI, MARIA H.T. ; SILVA, PAULO S.C. da . Resultados atualizados das análises radioquímicas das amostras de concentrado de evaporador de Angra 1 e Angra 2 recebidas no IPEN em 2018 e 2019. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEENG, Abril, 2023. (IPEN-CEN-P&D-ETN-218-01-RELT-005-00). Restrito.

    Título do projeto: Composição Isotópica dos Rejeitos Radioativos da CNAAA

    Abstract: Este documento tem como objetivo apresentar as determinações de concentração de atividade dos radionuclídeos emissores de radiação gama, emissores alfa e emissores beta em amostras do Concentrado do Evaporador, das unidades de Angra 1 e Angra 2 da Eletronuclear. Essas determinações referem-se às amostras recebidas no SEGRR do IPEN-CNEN/SP em 2018, em continuidade ao relatório anteriormente encaminhado; IPEN-CEN-P&D-ETN-218-01-INFT-002- 00. “Resultados das análises radioquímicas das amostras de concentrado do evaporador e resinas de Angra I (referente às amostras existentes em 2017)” [1]. O presente relatório técnico foi elaborado em atendimento ao item 8.3.1, “Resultados atualizados das análises radioquímicas das amostras de rejeitos”, do Plano de trabalho anexo ao Acordo “Determinação da Composição Isotópica dos Rejeitos Radioativos da CNAAA (Fase B)”, do ACORDO DE PARCERIA TECNOLÓGICA firmado entre a ELETROBRÁS TERMONUCLEAR S.A., a CNEN - COMISSÃO NACIONAL DE ENERGIA NUCLEAR e a FUNDEP – Fundação de Desenvolvimento da Pesquisa.

    Palavras-Chave: radioactive wastes; sampling; evaporators; radiochemical analysis; radioisotopes

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  • IPEN-DOC 29645

    VICENTE, ROBERTO ; DELLAMANO, JOSE C. ; CABRERA, PALOMA S. . Proposição do plano de amostragem dos rejeitos históricos. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEENG, Abril, 2023. (IPEN-CEN-P&D-ETN-218-01-RELT-004-00). Restrito.

    Título do projeto: Composição Isotópica dos Rejeitos Radioativos da CNAAA

    Abstract: Este relatório técnico tem como objetivo propor um plano de amostragem para caracterização radioisotópica dos rejeitos radioativos históricos armazenados no Centro de Gerenciamento de Rejeitos (CGR) da Central Nuclear Almirante Álvaro Alberto (CNAAA) e foi elaborado em atendimento ao item 8.3.3 do Plano de trabalho anexo ao Acordo “Determinação da Composição Isotópica dos Rejeitos Radioativos da CNAAA (Fase B)”, do ACORDO DE PARCERIA TECNOLÓGICA firmado entre a ELETROBRÁS TERMONUCLEAR S.A., a CNEN - COMISSÃO NACIONAL DE ENERGIA NUCLEAR e a FUNDEP – Fundação de Desenvolvimento da Pesquisa.

    Palavras-Chave: radioactive wastes; waste storage; waste management; isotope ratio; radioisotopes

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  • IPEN-DOC 29644

    MEDEIROS, JOSE A.G. de ; SOUZA, FRANCISCO de A. ; GENEZINI, FREDERICO A. ; ZAHN, GUILHERME S. ; YORIYAZ, HELIO ; SILVA JUNIOR, IREMAR A. da ; MORALLES, MAURICIO . Procedimentos para espectroscopia gama dos Geradores de Vapor e da Tampa do Vaso do Reator depositados no DIGV. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEENG, Abril, 2023. (IPEN-CEN-P&D-ETN-218-01-RELT-003-00). Restrito.

    Título do projeto: Composição Isotópica dos Rejeitos Radioativos da CNAAA

    Abstract: Este documento tem como objetivo apresentar um conjunto de procedimentos para a realização das medidas de espectroscopia gama nos Geradores de Vapor (GVs) e da Tampa do Vaso do Reator (TVR), removidos de Angra 1 , respectivamente, em 2009 e 2013, e que se encontram no Depósito Inicial dos Geradores de Vapor (DIGV) no sítio da Central Nuclear Almirante Álvaro Alberto (CNAAA). As medidas de espectrometria gama visam possibilitar a avaliação do inventário dos radioisótopos gama emissores dessas estruturas. Esse inventário, associado aos dados de concentração de atividade dos radioisótopos presentes em amostras representativas dos GVs e da TVR, possibilitará a proposição de um inventário radioisotópico estendido dessas estruturas. Adicionalmente, este trabalho apresenta também a proposição das atividades de mapeamento dosimétrico dos GVs e da TVR, atividades que devem ser desempenhadas simultaneamente às atividades de espectrometria. A apresentação deste documento visa atender ao cumprimento da atividade 8.3.4. “Planejamento da espectroscopia gama dos Geradores de Vapor e da Tampa do Vaso do Reator” do plano de trabalho, anexo ao acordo de parceria tecnológica existente entre o IPEN, a Eletronuclear e a Fundep.

    Palavras-Chave: steam generators; reactor vessels; gamma spectroscopy; radioactive waste management; waste storage

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  • IPEN-DOC 29643

    BELCHIOR JUNIOR, ANTONIO ; BEZERRA, JABISON R. de A. ; RIBEIRO, MARIA A.M. . Módulo de entrada do programa CAREN. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEENG, Abril, 2023. (IPEN-CEN-P&D-ETN-218-01-RELT-002-00). Restrito.

    Título do projeto: Composição Isotópica dos Rejeitos Radioativos da CNAAA

    Abstract: Este trabalho tem como finalidade apresentar, em detalhes, o Módulo de Entrada do Sistema Computacional de Avaliação do Ativo Isotópico. O sistema computacional de Avaliação do Ativo Isotópico tem a função de avaliar o inventário isotópico dos embalados gerados da CNAAA (Central Nuclear Almirante Álvaro Alberto) no qual são armazenados rejeitos radioativos com atividades baixa e intermediária. E será responsável por estimar o inventário isotópico básico do depósito inicial da CNAAA a partir dos dados típicos de geração dos rejeitos radioativos das diferentes matrizes provenientes de cada uma das usinas nucleoelétricas em operação no âmbito da CNAAA, dados estes provenientes do RejAn. O módulo de entrada do programa, juntamente com outros dois módulos - Módulo de Cálculo e Módulo de Saída – constituem o Programa CAREN. O módulo de entrada apresenta diversas janelas que possibilitarão ao usuário ter acesso aos dados de entrada advindos tanto da importação de dados armazenados no RejAn quanto da tabela de Fatores de Escala (FE). Neste documento são apresentadas as especificações da interface como RejAn e também, o acoplamento com a tabela de Fatores de Escala (FE). Por fim, este documento traz dados sobre a especificação de teste de software. Este documento em conjunto com o documento “Cálculos que serão efetuados pelo sistema computacional para avaliação do Ativo Isotópico, incluindo fatores de escala e, correlações” [1], além dos documentos emitidos na Fase A do projeto “Especificação Funcional do sistema computacional para avaliação do ativo isotópico” [2], e “Cálculos que serão efetuados pelo sistema computacional para avaliação do Ativo Isotópico” [3] e “Estudo das cadeias de decaimento para uso no programa de avaliação do ativo isotópico” [4], define como será o sistema de entrada, o recebimento de dados provenientes do RejAn, a especificação do módulo de atualização da tabela dos fatores de escala e o teste do software. Este documento foi emitido para atender aos requisitos do acordo de P&D Ativo Isotópico Fase B, conforme item 8.3.6 do Plano de Trabalho, onde se lê:” Módulo de Entrada do Programa de Avaliação do Ativo Isotópico, incluindo especificações do módulo de entrada com interface com RejAn e acoplamento com Tabela de Fatores de Escala (FE); especificação do módulo de atualização da tabela de Fatores de Escala (FE) e especificação de teste de Software.”.

    Palavras-Chave: isotope ratio; computer codes; inventories; radioisotopes; systems analysis

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  • IPEN-DOC 29642

    RIBEIRO, MARIA A.M. ; BELCHIOR JUNIOR, ANTONIO ; BEZERRA, JABISON R. de A. . Cálculos que serão efetuados pelo sistema computacional para avaliação do ativo isotópico, incluindo fatores de escala e correlações. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEENG, Maio, 2023. (IPEN-CEN-P&D-ETN-218-01-RELT-001-00). Restrito.

    Título do projeto: Composição Isotópica dos Rejeitos Radioativos da CNAAA

    Abstract: O presente trabalho tem como finalidade desenvolver um sistema computacional para avaliação do inventário isotópico dos embalados que armazenam rejeitos radioativos de baixa e média atividades gerados pela CNAAA (Central Nuclear Almirante Álvaro Alberto). O sistema computacional será responsável por realizar cálculos para estimar o inventário isotópico básico para os embalados contidos no depósito inicial da CNAAA a partir dos dados típicos de geração dos rejeitos radioativos das diferentes matrizes provenientes de cada uma das usinas nucleoelétricas em operação no âmbito da CNAAA. Este documento apresenta a metodologia de cálculo que será utilizada no sistema computacional para avaliação deste ativo isotópico. Este documento em conjunto com os documentos emitidos na Fase A do projeto “Especificação Funcional do sistema computacional para avaliação do ativo isotópico” [1] , “Cálculos que serão efetuados pelo sistema computacional para avaliação do Ativo Isotópico” [2] e “Estudo das cadeias de decaimento para uso no programa de avaliação do ativo isotópico” [3], definem como será o sistema computacional para avaliação do ativo isotópico. Este documento foi emitido para complementar os requisitos do acordo de P&D Ativo Isotópico Fase B, conforme item 8.3.6 do Plano de Trabalho.

    Palavras-Chave: computer codes; systems analysis; isotopes; inventories; radioactive wastes

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  • IPEN-DOC 29641

    RIBEIRO, MARIA A.M. . Estudo das cadeias de decaimento para uso no programa de avaliação do ativo isotópico. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEENG, Abril, 2023. (IPEN-CEN-P&D-ETN-196-00-RELT-002-03). Restrito.

    Título do projeto: Composição Isotópica dos Rejeitos Radioativos da CNAAA

    Abstract: O presente trabalho visa resumir e fornecer todos os dados de meia vida dos radioisótopos que eventualmente estarão presentes nos rejeitos radiativos das usinas de Angra 1, 2 e 3. Os radioisótopos foram divididos entre: produtos de ativação, produtos de fissão, produtos de decaimento dos transurânicos, radionuclídeos que decaem por captura de elétron e radionuclídeos produtos de Ativação Beta Emissores Exclusivos. Os radionuclídeos de difícil medição (RDMs) estão marcados em verde nas tabelas.

    Palavras-Chave: radioisotopes; radioactive wastes; decay; angra-1 reactor; angra-2 reactor; angra-3 reactor

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  • IPEN-DOC 29640

    SILVA, DANIEL J. da; DURAN, ADRIANA; CABRAL, ALINE D.; FONSECA, FERNANDO L.A.; WANG, SHU H.; PARRA, DUCLERC F. ; BUENO, RODRIGO F.; PEREYRA, INES; ROSA, DERVAL S.. Bioinspired antimicrobial PLA with nanocones on the surface for rapid deactivation of Omicron SARS-CoV‑2. ACS Biomaterials Science and Engineering, v. 9, n. 4, p. 1891-1899, 2023. DOI: 10.1021/acsbiomaterials.2c01529

    Abstract: Bioinspired bactericidal surfaces are artificial surfaces that mimic the nanotopography of insect wings and are capable of inhibiting microbial growth by a physicomechanical mechanism. The scientific community has considered them an alternative method to design polymers with surfaces that inhibit bacterial biofilm formation, suitable for self-disinfectant medical devices. In this contribution, poly(lactic acid) (PLA) with nanocone patterns was successfully produced by a novel two-step procedure involving copper plasma deposition followed by argon plasma etching. According to reverse transcription-quantitative polymerase chain reaction tests, the bioinspired PLA nanostructures display antiviral performance to inactivate infectious Omicron severe acute respiratory syndrome coronavirus 2 particles, reducing the amount of the viral genome to less than 4% in just 15 min due to a possible combined effect of mechanical and oxidative stress. The bioinspired antiviral PLA can be suitable for designing personal protection equipment to prevent the transmission of contagious viral diseases, such as Coronavirus Disease 2019.

    Palavras-Chave: coronaviruses; topography; surfaces; copper; lactic acid; polymers; antimicrobial agents

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  • IPEN-DOC 29639

    SANTOS, SOFIA N. dos ; GUSHIKEN JUNIOR, DINO S. ; PEREIRA, JHONATAS P.M. ; IADOCICCO, NATALIA M. ; SILVA, ANDRE H. ; NASCIMENTO, TATIELLE do; DIAS, LUIS A.P. ; SILVA, FLAVIA R. de O. ; RICCI-JUNIOR, EDUARDO; SANTOS-OLIVEIRA, RALPH; BERNARDES, EMERSON S. . Development of glycan‑targeted nanoparticles as a novel therapeutic opportunity for gastric cancer treatment. Cancer Nanotechnology, v. 14, n. 1, p. 1-21, 2023. DOI: 10.1186/s12645-023-00161-2

    Abstract: Chemotherapy resistance remains a major cause of therapeutic failure in gastric cancer. The combination of genetic material such as interference RNAs (iRNAs) to silence cancer-associated genes with chemotherapeutics has become a novel approach for cancer treatment. However, finding the right target genes and developing non-toxic, highly selective nanocarrier systems remains a challenge. Here we developed a novel sialyl-Tn-targeted polylactic acid—didodecyldimethylammonium bromide nanoparticle (PLA-DDAB) nanoparticles (NPs) loaded with dsRNA targeting ST6GalNac-I and/or galectin-3 genes. Using single photon emission computed tomography (SPECT), we have demonstrated that 99mtechnetium radiolabeled sialyl-Tn-targeted nanoparticles can reach the tumor site and downregulate ST6GalNAc-I and galectin-3 RNA expression levels when injected intravenously. Furthermore, using an in vivo gastric tumor model, these nanoparticles increased the effectiveness of 5-FU in reducing tumor growth. Our findings indicate that cancer-associated glycan-targeted NPs loaded with dsRNA targeting ST6GalNAc-I and/or galectin-3 in combination with standard chemotherapy, have the potential to become a novel therapeutic tool for gastric cancer.

    Palavras-Chave: neoplasms; stomach; rna; antigens; chemotherapy

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  • IPEN-DOC 29638

    MIRANDA, RANULFO B. de P.; USSUI, VALTER ; LAZAR, DOLORES R.R. ; LIMA, NELSON B. de ; MARCHI, JULIANA; CESAR, PAULO F.. Characterization of 3Y-TZP/TiO2 hybrid experimental dental ceramics. Ceramics International, v. 49, n. 10, p. 15734-15740, 2023. DOI: 10.1016/j.ceramint.2023.01.167

    Abstract: The addition of titania to zirconia dental implants has been considered a promising choice to improve its bioactivity. This study aimed to evaluate the effect of different sintering conditions on the microstructure, density, optical properties and flexural strength of a 3Y-TZP/TiO2 dental ceramic based on zirconia with two different titania contents (7.5 mol% and 12.5 mol%). 3Y-TZP/TiO2 ceramic powders were synthesized by coprecipitation, uniaxially pressed and sintered at six different sintering conditions. Microstructural analysis of the sintered samples was performed by scanning electron microscopy and X-ray diffraction. Optical properties were measured using a spectrophotometer. The density was determined by Archimedes principle. Flexural strength was estimated by the biaxial flexure device. The microstructure and flexural strength of the 3Y-TZP/TiO2 dental ceramic with 7.5% and 12.5 mol% were affected by the sintering conditions. Sintering the specimens at 1460 °C for 2 h increased the grain size and significantly decreased the flexural strength of 3Y-TZP/TiO2 dental ceramic. The interaction (titania content x sintering conditions) affected the relative density and optical properties. A relative density greater than 98% was achieved for the T7.5 groups (sintered at 1260 °C/1 h, 1300 °C/1 h and 1300 °C/2 h) and for the T12.5 groups (sintered at 1260 °C/1 h, 1260 °C/4 h, 1300 °C/1 h and 1300 °C/2 h). The highest values of L*, a* and b* were respectively 87.2 (T7.5 group sintered at 1460 °C/2hs), 4.3 (T12.5 group sintered at 1300 °C/2hs) and 15.8 (T12.5 group sintered at 1300 °C/1 h). The material developed with 12.5 mol% of titania and sintered at 1300 °C/2 h showed high densification, flexural strength of 670 MPa and has good potential to be used in dentistry.

    Palavras-Chave: yttrium oxides; zirconium oxides; titanium oxides; dentistry; ceramics; implants; optical properties; flexural strength; sintering

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  • IPEN-DOC 29637

    YOSHIMURA, TANIA M. ; CABRAL, FERNANDA V. ; SELLERA, FABIO P.; POZZO, LORENA ; RIBEIRO, MARTHA S. . Could light-based technologies improve stem cell therapy for skin wounds?: A systematic review and meta-analysis of preclinical studies. Photochemistry and Photobiology, v. 99, n. 2, p. 519-528, 2023. DOI: 10.1111/php.13702

    Abstract: Several diseases or conditions cause dermatological disorders that hinder the process of skin repair. The search for novel technologies has inspired the combination of stem cell (SC) and light-based therapies to ameliorate skin wound repair. Herein, we systematically revised the impact of photobiomodulation therapy (PBM) combined with SCs in animal models of skin wounds and quantitatively evaluated this effect through a meta-analysis. For inclusion, SCs should be irradiated in vitro or in vivo, before or after being implanted in animals, respectively. The search resulted in nine eligible articles, which were assessed for risk of bias. For the meta-analysis, studies were included only when PBM was applied in vivo, five regarding wound closure, and three to wound strength. Overall, a positive influence of SC + PBM on wound closure (mean difference: 9.69; 95% CI: 5.78–13.61, P < 0.00001) and strength (standardized mean difference: 1.7, 95% CI: 0.68–2.72, P = 0.001) was detected, although studies have shown moderate to high heterogeneity and a lack of information regarding some bias domains. Altogether, PBM seems to be an enabling technology able to be applied postimplantation of SCs for cutaneous regeneration. Our findings may guide future laboratory and clinical studies in hopes of offering wound care patients a better quality of life.

    Palavras-Chave: skin diseases; therapy; stem cells; biological repair

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  • IPEN-DOC 29636

    SABINO, CAETANO P.; RIBEIRO, MARTHA S. ; WAINWRIGHT, MARK; ANJOS, CAROLINA dos; SELLERA, FABIO P.; DROPA, MILENA; NUNES, NATHALIA B.; BRANCINI, GUILHERME T.P.; BRAGA, GILBERTO U.L.; ARANA-CHAVEZ, VICTOR E.; FREITAS, RAUL O.; LINCOPAN, NILTON; BAPTISTA, MAURICIO S.. The biochemical mechanisms of antimicrobial photodynamic therapy. Photochemistry and Photobiology, v. 99, n. 2, p. 742-750, 2023. DOI: 10.1111/php.13685

    Abstract: The unbridled dissemination of multidrug-resistant pathogens is a major threat to global health and urgently demands novel therapeutic alternatives. Antimicrobial photodynamic therapy (aPDT) has been developed as a promising approach to treat localized infections regardless of drug resistance profile or taxonomy. Even though this technique has been known for more than a century, discussions and speculations regarding the biochemical mechanisms of microbial inactivation have never reached a consensus on what is the primary cause of cell death. Since photochemically generated oxidants promote ubiquitous reactions with various biomolecules, researchers simply assumed that all cellular structures are equally damaged. In this study, biochemical, molecular, biological and advanced microscopy techniques were employed to investigate whether protein, membrane or DNA damage correlates better with dose-dependent microbial inactivation kinetics. We showed that although mild membrane permeabilization and late DNA damage occur, no correlation with inactivation kinetics was found. On the other hand, protein degradation was analyzed by three different methods and showed a dose-dependent trend that matches microbial inactivation kinetics. Our results provide a deeper mechanistic understanding of aPDT that can guide the scientific community toward the development of optimized photosensitizing drugs and also rationally propose synergistic combinations with antimicrobial chemotherapy.

    Palavras-Chave: antimicrobial agents; photodynamic therapy; biochemical reaction kinetics; microbial drug resistance

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  • IPEN-DOC 29635

    TESSARO, ANA P.G. ; ARAUJO, LEANDRO G. de ; SILVA, THALITA T. ; COELHO, EDNEI; CORREA, BENEDITO; ROLINDO, NATALIE C. ; VICENTE, ROBERTO . Prospects for fungal bioremediation of unburied waste packages from the Goiânia radiological accident. Environmental Science and Pollution Research, v. 30, n. 14, p. 41045-41059, 2023. DOI: 10.1007/s11356-023-25247-7

    Abstract: Goiânia, the Goiás State capital, starred in 1987, where one of the largest radiological accidents in the world happened. A teletherapy machine was subtracted from a derelict radiotherapy clinic and disassembled by scavengers who distributed fragments of the 50 TBq 137CsCl source among relatives and acquaintances, enchanted by the blue shine of the substance. During the 15 days before the accident was acknowledged, contaminated recycling materials were delivered to recycling factories in four cities in the state of São Paulo, Brazil, in the form of recycling paper bales. The contaminated bales were spotted, collected, and stored in fifty 1.6 m3 steel boxes at the interim storage facility of the Nuclear and Energy Research Institute (IPEN). In 2017, a check of the content was performed in a few boxes and the presence of high moisture content was observed even though the bales were dry when conditioned and the packages were kept sealed since then. The main objective of this work was to report the fungi found in the radioactive waste after they evolved for 30 years in isolation inside the waste boxes and their role in the decay of the waste. Examination of the microbiome showed the presence of nematodes and fungal communities. The fungi species isolated were Aspergillus quadricinctus, Fusarium oxysporum, Lecanicillium coprophilumi, Scedosporium boydii, Scytalidium lignicola, Xenoacremonium recifei, and Pleurostoma richardsiae. These microorganisms showed a significant capacity to digest cellulose in our trials, which could be one of the ways they survive in such a harsh environment, reducing the volume of radioactive paper waste. These metabolic abilities give us a future perspective of using these fungi in biotechnology to remediate radioactively contaminated materials, particularly cellulose-based waste.

    Palavras-Chave: radiation accidents; cesium 137; waste management; fungi; radioactive wastes; brazil

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  • IPEN-DOC 29634

    MATIATOS, IOANNIS; ARAGUAS-ARAGUAS, LUIS; WASSENAAR, LEONARD I.; MONTEIRO, LUCILENA R. ; HARJUNG, ASTRID; DOUENCE, CEDRIC; KRALIK, MARTIN. Nitrate isotopes reveal N-cycled waters in a spring-fed agricultural catchment. Isotopes in Environmental and Health Studies, v. 59, n. 1, p. 27-47, 2023. DOI: 10.1080/10256016.2022.2157412

    Abstract: Nitrate stable isotopes provide information about nitrate contamination and cycling by microbial processes. The Fischa-Dagnitz (Austria) spring and river system in the agricultural catchment of the Vienna basin shows minor annual variance in nitrate concentrations. We measured nitrate isotopes (δ15N, δ18O) in the source spring and river up to the confluence with the Danube River (2019–2020) with chemical and water isotopes to assess mixing and nitrate transformation processes. The Fischa-Dagnitz spring showed almost stable nitrate concentration (3.3 ± 1.0 mg/l as NO3–-N) year-round but surprisingly variable δ15N, δ18O-NO3– values ranging from +5.5 to +11.1‰ and from +0.5 to +8.1‰, respectively. The higher nitrate isotope values in summer were attributed to release of older denitrified water from the spring whose isotope signal was dampened downstream by mixing. A mixing model suggested denitrified groundwater contributed > 50 % of spring discharge at baseflow conditions. The isotopic composition of NO3– in the gaining streams was partly controlled by nitrification during autumn and winter months and assimilation during the growing season resulting in low and high δ15N-NO3– values, respectively. NO3– isotope variation helped disentangle denitrified groundwater inputs and biochemical cycling processes despite minor variation of NO3– concentration.

    Palavras-Chave: agriculture; biogeochemistry; denitrification; ground water; mixing; hydrology; isotopes; nitrogen 15; nitrates; oxygen 18

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  • IPEN-DOC 29633

    RAMON, MAURO; RIBEIRO, ANDREZA P.; THEOPHILO, CAROLINA Y.S. ; MOREIRA, EDSON G. ; CAMARGO, PLINIO B. de; PEREIRA, CARLOS A. de B.; SARAIVA, ERLANDSON F.; TAVARES, ARMANDO dos R.; DIAS, ANTONIO G.; NOWAK, DAVID; FERREIRA, MAURICIO L.. Assessment of four urban forest as environmental indicator of air quality: a study in a brazilian megacity. Urban Ecosystems, v. 26, n. 1, p. 197-207, 2023. DOI: 10.1007/s11252-022-01296-7

    Abstract: Vehicular emissions comprise a main source of air pollutants, especially particulate matter (PM), which contains toxic compounds. Brazil has been restricting vehicular emissions for more than 30 years to minimize the impacts of fleet vehicles, but despite the restrictive legislation, several Brazilian cities still suffer from the effects of atmospheric pollution. The adoption of nature-based solutions (NbS) is being hailed as a sound alternative for improving urban air quality. In this sense, trees are a true reflection of the NbS concept since they can directly decrease PM levels by intercepting and resuspending particles, as well as altering pollution dispersion patterns. We wanted to understand the practical outcome of urban forest fragments as an NbS. Therefore, using litterfall in urban forest fragments, this study reported the role of green areas in reducing air pollution concentrations in 4 urban parks in Sao Paulo Megacity, Brazil. Air contaminants (Cd, Cu and Pb) varied from the edge to the core of urban forests. Multivariate analysis revealed that areas with different vehicle fleets influenced the input of air pollutants into these forest fragments. Our study further showed that trees serve as a natural barrier against PM. It can be concluded that this low-cost NbS alternative can reduce air pollution and has a potential to improve human health and well-being, and should be incorporated into municipal policies and programs, especially in critical locations of high human density. and poorly managed green areas.

    Palavras-Chave: urban areas; forests; environmental policy; planning

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  • IPEN-DOC 29632

    SOUZA, VIVIANE C. de; RAMOS, GABRIEL dos S.; LEITE, JULIANA L.; SANTOS, MAURICIO B. dos; OTUBO, LARISSA ; CAMARGO, ZAINE T.; VICTOR, MAURICIO M.. A new thioglycolic ester β-cyclodextrin/PdCl2 in water: an accessible catalyst for the Suzuki-Miyaura coupling reaction. Carbohydrate Polymers, v. 301, n. Part A, p. 1-10, 2023. DOI: 10.1016/j.carbpol.2022.120271

    Abstract: A novel, easily prepared and accessible water-soluble supramolecular catalyst for the Suzuki-Miyaura Csingle bondC coupling reaction was synthesized and characterized by FTIR, NMR, XRD, SEM, and HR-TEM. An inexpensive Pd(II) source added to the resulting aqueous solution of thioglycolic ester β-cyclodextrin (1-TGA-SH-β-CD/PdCl2) showed Pd nanoclusters and efficient catalytic activity for Suzuki-Miyaura Csingle bondC coupling reactions of aryl halides with aryl boronic acids, employing K2CO3 as base, in an environmentally benign aqueous solution prepared in open flasks. Organic aryl halides including chlorides can produce moderate to excellent yields with aryl boronic acids and a small catalytic amount (0.01 mol%) of 1-TGA-SH-β-CD/PdCl2. This hydro-soluble catalyst stock solution was stable for long periods (more than three months) and could be reused in two runs until showing loss of catalytic activity. Some experiments to understand the mechanism were performed, with the results suggesting incorporation of aryl halide in the catalytic cavity.

    Palavras-Chave: thiols; dextrin; catalysts; palladium complexes; halides; aqueous solutions; aqueous solutions

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  • IPEN-DOC 29631

    ANTUNES, PAULA C.G. ; SIQUEIRA, PAULO de T.D. ; SHORTO, JULIAN M.B. ; YORIYAZ, HELIO . A versatile physical phantom design and construction for I-125 dose measurements and dose-to-medium determination. Brachytherapy, v. 22, n. 1, p. 80-92, 2023. DOI: 10.1016/j.brachy.2022.10.005

    Abstract: PURPOSE: In this paper we present a phantom designed to provide conditions to generate set of “true” independent reference data as requested by TG-186, and mitigating the scarcity of experimental studies on brachytherapy validation. It was used to perform accurate experimental measurements of dose of 125I brachytherapy seeds using LiF dosimeters, with the objective of experimentally validating Monte Carlo (MC) calculations with model-based dose calculation algorithm (MBDCA). In addition, this work intends to evaluate a methodology to convert the experimental values from LiF into dose in the medium. METHODS AND MATERIALS: The proposed PMMA physical phantom features cavities to insert a LiF dosimeter and a 125I seed, adjusted in different configurations with variable thickness. Monte Carlo calculations performed with MCNP6.2 code were used to score the absorbed dose in the LiF and the dose conversion parameters. A sensitivity analysis was done to verify the source of possible uncertainties and quantify their impact on the results. RESULTS: The proposed phantom and experimental procedure developed in this work provided precise dose data within 5.68% uncertainty (k = 1). The achieved precision made it possible to convert the LiF responses into absorbed dose to medium and to validate the dose conversion factor methodology. CONCLUSIONS: The proposed phantom is simple both in design and as in its composition, thus achieving the demanded precision in dose evaluations due to its easy reproducibility of experimental setup. The results derived from the phantom measurements support the dose conversion methodology. The phantom and the experimental procedure developed here can be applied for other materials and radiation sources.

    Palavras-Chave: biological models; phantoms; brachytherapy; iodine 125; seeds; lithium fluorides; monte carlo method

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  • IPEN-DOC 29630

    JESUS, JULIANA M.S. de; ARGOLO, ALLAN dos S.; TOMINAGA, FLAVIO K. ; TAQUEDA, MARIA E.; BILA, DANIELE M.; BORRELY, SUELI I. ; TEIXEIRA, ANTONIO C.S.C.. Experimental design and bioassays as tools to investigate the impact of anodic oxidation on progestins degradation. Water, v. 15, n. 1, p. 1-18, 2023. DOI: 10.3390/w15010061

    Abstract: The present study investigated the degradation of levonorgestrel (LNG) and gestodene (GES) through an anodic oxidation process mediated by active chlorine species. The independent variables [LNG]0 and [GES]0, current density (mA cm−2), and [NaCl]0 (mol L−1) were optimized through a response surface methodology (RSM) based on a four-level central composite design (CCD). Specific energy consumption allowed CCD-RSM analysis and optimization. The decay of progestins was followed to verify the kinetics of the anodic degradation process. Chlorine monitoring showed that excess Cl− concentration did not mean high hormones removal, as well as the excess of current density. Central point conditions ([NaCl]0 = 0.07 mol L−1, j = 32.5 mA cm−2, [LNG]0, and [GES]0 1.0 mg L−1) proved to be the best operational option. The performance with real pharmaceutical wastewater confirmed model optimization (2.2 ± 0.2 kWh g−1, with removals of 83.1 ± 0.9% and 75.1 ± 2.8% for LNG and GES, respectively). The selected condition was used for estrogenic activity and acute toxicity assays. The first allowed the identification of the initial estrogenic activity for the mixture of LNG and GES (924 E2-EQ ng L−1). Additionally, the electrochemical process could decrease this environmental parameter by 74.6%. The progestin mixture was classified as acute toxicity to Daphnia similis, with a toxicity unit (TU) of 2.5 100/EC50%. After electrolysis, the hormone solutions reached a fourfold increase in TU value, classified as high acute toxicity.

    Palavras-Chave: composite materials; design; progesterone; waste water; drugs; estrogens; hormones; water pollution

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  • IPEN-DOC 29629

    MARCHIOLI, CARLOS A. ; ALMEIDA, GISELE F.C. ; GONCALVES, RODOLFO L.P.; XAVIER, MARCOS D.; SANTOS, GIVANILDO A. dos; COUTO, ANTONIO A. . Influência na microestrutura e propriedades mecânicas da liga de alumínio A380 fundida sob pressão pela variação nas velocidades de injeção / Influence in the microstructure and mechanical properties of the aluminum alloy A380 die casting by the injection speed steps. Tecnologia em Metalurgia, Materiais e Mineração, v. 20, p. 1-9, 2023. DOI: 10.4322/2176-1523.20222804

    Abstract: Na fundição sob pressão de ligas de alumínio, devido à alta velocidade de injeção do metal líquido no molde, obtém-se uma microestrutura com grãos refinados e possível ocorrência de defeitos como microporosidade e microrechupes. Esses defeitos podem ocorrer devido a deficiências no projeto do ferramental, na definição dos parâmetros de cálculo ou mesmo no controle dos parâmetros de injeção. O objetivo deste trabalho é analisar a influência das velocidades das fases de injeção (primeira e segunda fases) na microestrutura e propriedades mecânicas da liga de alumínio A380. Corpos de prova foram moldados sob pressão de matriz em uma máquina de injeção de câmara fria. A faixa de velocidade de injeção do processo foi de 0,10 m/s, 0,25 m/s e 0,50 m/s para a primeira fase, e 0,6 m/s, 1,5 m/s 3,0 m/s para a segunda fase. As propriedades mecânicas foram determinadas por meio de ensaios de tração e dureza e a caracterização microestrutural por microscopia óptica. Os resultados indicaram que a velocidade de injeção não influencia o limite de resistência tanto da primeira quanto da segunda fase de injeção. No entanto, o nível de porosidade e erros de execução mudaram em função das variações de velocidade, fatores que afetam o resultado do alongamento e limite de escoamento dos produtos de fundição sob pressão.

    Palavras-Chave: castings; hardness; tensile properties; aluminium alloys; microstructure

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  • IPEN-DOC 29628

    CAIXETA, DOUGLAS C.; LIMA, CASSIO ; XU, YUN; GUEVARA-VEGA, MARCO; ESPINDOLA, FOUED S.; GOODACRE, ROYSTON; ZEZELL, DENISE M. ; SABINO-SILVA, ROBINSON. Monitoring glucose levels in urine using FTIR spectroscopy combined with univariate and multivariate statistical methods. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, v. 290, p. 1-9, 2023. DOI: 10.1016/j.saa.2022.122259

    Abstract: The development of novel platforms for non-invasive continuous glucose monitoring applied in the screening and monitoring of diabetes is crucial to improve diabetes surveillance systems. Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy of urine can be an alternative as a sustainable, label-free, fast, non-invasive, and highly sensitive analysis to detect changes in urine promoted by diabetes and insulin treatment. In this study, we used ATR-FTIR to evaluate the urinary components of non-diabetic (ND), diabetic (D), and diabetic insulin-treated (D + I) rats. As expected, insulin treatment was capable to revert changes in glycemia, 24-h urine collection volume, urine creatinine, urea, and glucose excretion promoted by diabetes. Several differences in the urine spectra of ND, D, and D + I were observed, with urea, creatinine, and glucose analytes being related to these changes. Principal components analysis (PCA) scores plots allowed for the discrimination of ND and D + I from D with an accuracy of ∼ 99 %. The PCA loadings associated with PC1 confirmed the importance of urea and glucose vibrational modes for this discrimination. Univariate analysis of second derivative spectra showed a high correlation (r: 0.865, p < 0.0001) between the height of 1074 cm-1 vibrational mode with urinary glucose concentration. In order to estimate the amount of glucose present in the infrared spectra from urine, multivariate curve resolution-alternating least square (MCR-ALS) was applied and a higher predicted concentration of glucose in the urine was observed with a correlation of 78.9 % compared to urinary glucose concentration assessed using enzyme assays. In summary, ATR-FTIR combined with univariate and multivariate chemometric analyses provides an innovative, non-invasive, and sustainable approach to diabetes surveillance.

    Palavras-Chave: diabetes mellitus; fourier transform spectrometers; infrared spectra; urine; biological markers; quantitative chemical analysis; glucose

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  • IPEN-DOC 29627

    TOMINAGA, FLAVIO K. ; BOIANI, NATHALIA F. ; SILVA, THALITA T. ; SANTOS, JONAS G. dos; LEBRE, DANIEL T. ; LEO, PATRICIA; BORRELY, SUELI I. . Electron beam irradiation applied for the detoxification and degradation of single ciprofloxacin aqueous solution and multiclass pharmaceutical quaternary mixture. Separation and Purification Technology, v. 307, p. 1-9, 2023. DOI: 10.1016/j.seppur.2022.122818

    Abstract: The application of electron beam irradiation for detoxification and degradation of single antibiotic ciprofloxacin (CPF) and in a mixture with multiclass pharmaceuticals in aqueous solutions was carried out. Ecotoxicity assays indicated that the green algae were most sensitive to antibiotic and also that the presence of several pharmaceutical increased the toxicity. After the irradiation treatment, degradation results of single antibiotic indicated reduction of 95.86 % at 1.0 kGy. Total organic carbon decreased up to 38 % at 5.0 kGy. At lower doses (1.0 kGy), no effect in toxicity was evidenced, however, increase in toxicity for Vibrio fischeri was observed after 2.5 kGy. For Daphnia similis exposure, an increase in toxicity was noted for all applied doses. In contrast, for the green algae R. subcapitata toxicity reduction varied from 62.3 to 81.9 % at the evaluated doses. Toxicity assays to microbes E. coli and S. aureus reduced antibacterial activity of CPF after irradiation treatment. Regarding the irradiated quaternary mixture at 2.5 kGy, reduction up to 96 % was achieved for the ciprofloxacin, metformin and acetylsalicylic acid, and 81 % removal was achieved for fluoxetine. Acute assays with V. fischeri indicated no increase in toxicity, while some increase was noted for D. similis (acute effects). Nevertheless, chronic assays data indicated low toxicity reduction (14 %) with D. similis, and complete detoxification was shown for the green algae after the irradiation. In addition, decrease in antimicrobial activity was noted after the treatment. Furthermore, the in-silico model was not enough accurate for the prediction of CIP toxicity. These findings showed that electron beam irradiation can be applied for reducing the impacts of antibiotics in aquatic ecosystem. Measuring toxicity on living-organism from different trophic levels are useful tools to evaluate the interaction of mixtures and also to assess toxicity of the generated byproducts.

    Palavras-Chave: electron beams; antibiotics; toxicity; drugs; water pollution; water treatment; irradiation

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  • IPEN-DOC 29626

    XIAO, DA; WANG, NANCHAO; CHEN, SIJIE; WU, LINGYUN; MULLER, DETLEF; VESELOVSKII, IGOR; LI, CHENGCAI; LANDULFO, EDUARDO ; SIVAKUMAR, VENKATARAMAN; LI, JING; CHE, HUIZHENG; FANG, JING; ZHANG, KAI; WANG, BINYU; CHEN, FEITONG; HU, XIANZHE; LI, XIAOTAO; LI, WEIZE; TONG, YICHENG; KE, JU; WU, LAN; LIU, CHONG; LIU, DONG. Simultaneous profiling of dust aerosol mass concentration and optical properties with polarized high-spectral-resolution lidar. Science of the Total Environment, v. 872, p. 1-13, 2023. DOI: 10.1016/j.scitotenv.2023.162091

    Abstract: Dust particles originating from arid desert regions can be transported over long distances, presenting severe risks to climate, environment, social economics, and human health at the source and downwind regions. However, there has been a dearth of continuous diurnal observations of vertically resolved mass concentration and optical properties of dust aerosols, which hinders our understanding of aerosol mixing, stratification, aerosol-cloud interactions, and their impacts on the environment. To fill the gap of the insufficient observations, to the best of our knowledge, this work presents the first high-spectral-resolution lidar (HSRL) observation providing days of continuous profiles of the mass concentration, along with particle linear depolarization ratio (PLDR), backscattering coefficient, extinction coefficient and lidar ratio (LR), simultaneously. We present the results of two strong dust events observed by HSRL over Beijing in 2021. The maximum particle mass concentrations reached (1.52 ± 3.5) x103 μg/m3 and (19.48 ± 0.36) x103 μg/m3 for the two dust events, respectively. The retrieved particle mass concentrations and aerosol optical depth (AOD) agree well with the observation from the surface PM10 concentrations and sun photometer with correlation coefficients of 0.90 and 0.95, respectively. The intensive properties of PLDR and LR of the dust aerosols are 0.31 ± 0.02 and 39 ± 7 sr at 532 nm, respectively, which are generally close to those obtained from observations in the downwind areas. Moreover, inspired by the observations from HSRL, a universal analytical relationship is discovered to evaluate the proportion of dust aerosol backscattering, extinction, AOD, and mass concentration using PLDR. The universal analytical relationship reveals that PLDR can directly quantify dust aerosol contribution, which is expected to further expand the application of polarization technology in dust detection. These valuable observations and findings further our understanding of the contribution of dust aerosol to the environment and help supplement dust aerosol databases.

    Palavras-Chave: dusts; aerosols; particles; optical radar; environmental impacts

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  • IPEN-DOC 29625

    SPATAFORA, A.; CARBONE, D.; CAPPUZZELLO, F.; CAVALLARO, M.; ACOSTA, L.; AGODI, C.; AMADOR-VALENZUELA, P.; BORELLO-LEWIN, T.; BRISCHETTO, G.A.; CALABRESE, S.; CALVO, D.; CAPIROSSI, V.; CHAVEZ LOMELI, E.R.; CIRALDO, I.; DE GREGORIO, G.; DELAUNAY, F.; DJAPO, H.; EKE, C.; FINOCCHIARO, P.; FIRAT, S.; FISICHELLA, M.; FOTI, A.; GARGANO, A.; HACISALIHOGLU, A.; IAZZI, F.; LA FAUCI, L.; LINARES, R.; LUBIAN, J.; MEDINA, N. ; MORALLES, M. ; OLIVEIRA, J.R.B.; PAKOU, A.; PANDOLA, L.; PETRASCU, H.; PINNA, F.; RUSSO, G.; SGOUROS, O.; SILVEIRA, M.A.G. da; SOLAKCI, S.O.; SOUKERAS, V.; SOULIOTIS, G.; TORRESI, D.; TUDISCO, S.; YILDIRIM, A.; ZAGATTO, V.A.B.. Multichannel experimental and theoretical approach to the 12C(18O, 18F)12B single-charge-exchange reaction at 275 MeV: initial-state interaction and single-particle properties of nuclear wave functions. Physical Review C, v. 107, n. 2, p. 024605-1 - 024605-19, 2023. DOI: 10.1103/PhysRevC.107.024605

    Abstract: Background: Single-charge-exchange reactions are appropriate tools to study the nuclear response to one-particle/one-hole isospin probes, gaining additional interest from the connection to beta decay. This analogy has been recently extended to second order, connecting double-charge-exchange reactions and double beta decays. Nowadays, the availability of powerful experimental setups and advanced nuclear theories and models allows one to access precious information on key nuclear structure aspects embedded in the widely sought neutrinoless double beta decay. Purpose: We intend to bring to light the main nuclear structure and reaction features involved in the 18O+12C collision at 275 MeV incident energy. In this paper, the main focus is on the role of the initial- and final-state interactions in the overall reaction dynamics and on the single-particle nuclear structure properties accessed via the study of single-nucleon transfer reactions. Forthcoming articles will be devoted to go into the details of the response to one- and two-particle/hole isospin probes. Methods: Cross-section energy spectra and angular distributions were measured in a unique experimental setup for the 12C(18O, 18O)12C elastic and inelastic scattering, the 12C(18O, 17O)13C one-neutron stripping, the 12C(18O, 19F)11B one-proton pickup, and the 12C(18O, 18F)12B single-charge-exchange nuclear reactions. A unique comprehensive and coherent theoretical calculation, able to describe the whole network of direct reactions using state-of-the-art nuclear structure and reaction theories, was performed, and it is presented for the first time in this article. This holistic approach, applied both to the experimental and theoretical analysis, is the main feature and worth of the work here presented. Results: The energy and angular resolutions achieved in each reaction channel allowed us to isolate specific transitions and to map the diffraction patterns in the angular distributions. The cross-section calculations describe well the experimental data, both in terms of the absolute values and diffraction patterns. Although the distorted wave Born approximation (DWBA) calculations prove to be accurate in describing all the studied channels, better results are achieved when the couplings to inelastic transitions in both the incoming and outgoing partitions are introduced, as done in the coupled channels Born approximation (CCBA) calculations. Otherwise, no real improvement is found when the coupling effects among different partitions are explicitly taken into account in the coupled reaction channels (CRC) calculations. Conclusions: The multichannel approach proposed in this paper is a promising method for accurate investigations of direct reactions originating in heavy-ion collisions. This is quite appealing for the precise spectroscopy of heavy nuclei proposed in many areas of nuclear physics. An example is the NUMEN project with its challenging commitment to provide valuable information on neutrinoless double beta decay nuclear matrix elements from single- and double-charge-exchange cross-section measurements.

    Palavras-Chave: nuclear matrix; charge-exchange reactions; excitation; wave functions; multi-channel analyzers

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  • IPEN-DOC 29624

    ANDRADE, MAIRA F. ; SARDO, ARIANE V.N. ; BENETTI, CAROLINA ; SICCHIERI, LETICIA B. ; CORREA, LUCIANA; ZEZELL, DENISE M. . Comparison of two light wavelengths (λ = 660 nm and λ = 780 nm) in the repair process of oral mucositis induced by ionizing radiation: clinical and microscopic evaluations in rats. Photonics, v. 10, n. 1, p. 1-13, 2023. DOI: 10.3390/photonics10010016

    Abstract: Photobiomodulation (PBM) has been clinically used for the prevention and treatment of oral mucositis (OM). The effect of red and near-infrared wavelengths on OM repair is still misunderstood. The aim of this study was to compare the clinical effect and tissue changes caused by 660 nm and 780 nm exposure in an experimental model of OM. Rats were submitted to gamma irradiation for induction of OM lesions and treated with 660 nm or 780 nm lasers with the same dosimetry parameters (30 mW, 7.5 J/cm2, 10 s, spot size = 0.04 mm, irradiation every two days). Clinical assessment of OM severity and histopathological analyses was performed after 8, 14, and 20 days of the ionizing radiation. OM severity was reduced in the PBM groups, especially when the red laser was used. The histopathological pattern was similar between the PBM groups, showing advanced re-epithelization and more pronounced angiogenesis and collagen deposition compared to the control. The 660 nm group showed a greater collagen matrix area than the 780 nm group at 14 days. In conclusion, PBM at 660 nm and 780 nm improved the repair of ionizing radiation-induced OM. Both wavelengths activated the angiogenesis and collagen deposition, but these tissue effects were more pronounced when 660 nm was used.

    Palavras-Chave: oral cavity; mucous membranes; injuries; radiotherapy; lasers; ionizing radiations

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  • IPEN-DOC 29623

    NOVAES, G.A.; BLANK, M.H.; YOSHIMURA, T.M. ; RIBEIRO, M.S. ; PEREIRA, R.J.G.. Methylene blue-mediated antimicrobial photodynamic therapy on chicken semen. Photodiagnosis and Photodynamic Therapy, v. 41, p. 1-12, 2023. DOI: 10.1016/j.pdpdt.2023.103290

    Abstract: Background: Artificial insemination is widely employed in poultry, but high degrees of bacterial contamination are often observed in semen because of its passage through the cloaca. Consequently, most semen extenders for birds have antibiotics that could aggravate bacterial resistance. Methods: We evaluated the potential of antimicrobial photodynamic therapy (PDT) as an alternative to the use of antibiotics, and assessed whether changes in concentration and incubation time with methylene blue (MB), radiant exposure, and irradiance of light affect spermatozoa activity and bacteria in chicken semen. Results: Incubation with MB (< 25 µM) did not alter sperm motility, regardless of the pre-irradiation time (PIT, 1 or 5 min). Following 1 min of PIT with MB at 10 µM, samples were irradiated for 30, 60, 120, and 180 s at irradiances of 44, 29, and 17 mW/ cm² (660 nm LedBox). MB and light alone did not interfere with the analyzed parameters. However, when both factors were associated, increases in light dose led to greater reductions in sperm parameters, regardless of the irradiance used. Besides, PDT conditions that were less harmful to spermatozoa were not able to significantly reduce bacterial colonies in chicken semen. Conclusions: A failure in MB selectivity could explain unsuccessful bacterial reduction following PDT. Further research involving other photosensitizers or conjugating molecules to MB to target microbial cells is needed for PDT application in poultry breeders.

    Palavras-Chave: fowl; antibiotics; reproduction; microorganisms; chickens; photodynamic therapy

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  • IPEN-DOC 29622

    PACOMPIA, YOLANDA; SUPO-RAMOS, JUSTO G.; GONZALES-LORENZO, CARLOS D.; CALLO-ESCOBAR, DARWIN J.; ROCCA, RENE R.; PASTRANA, ELIZABETH C.; GOMES, MONISE B. ; SILVA-CARRERA, BETZABEL N. ; WATANABE, S.; AYCA-GALLEGOS, OSCAR; AYALA-ARENAS, JORGE S.. Luminescence dating and firing temperature determination of ancient ceramics fragments from the Tunata-hill site in the Churajon archaeological complex in Arequipa, Peru. Radiation Physics and Chemistry, v. 204, p. 1-11, 2023. DOI: 10.1016/j.radphyschem.2022.110725

    Abstract: Ancient pottery fragments from the Tunata-hill site in Churajon archaeological complex, Arequipa, Peru, were dated by means of luminescence techniques such as thermoluminescence (TL) and optically stimulated luminescence (OSL) in order to provide absolute chronology. For TL, additive and regenerative methods were performed. For OSL a regenerative method was carried out for IRSL dating. A rigorous description of the study area and its context has been made. The ages of the samples were found to be between 0.50 ± 0.06 ky and 0.49 ± 0.03 ky for TL methods, and 0.49 ± 0.02 ky for OSL methods. On average, the estimated age by TL and OSL techniques is 490 ± 70 yr (1600 AD and 1460 AD). This means that Churajon ceramics under study would belong to the Late periods which corresponds to the Inca region, and the North sub-region of the Late Churajon phase, and the beginning of European colonization in Peru. X-ray fluorescence technique (XRF) analysis has shown the main presence of Fe (39.5%), Si (30.0%), and Al (10.4%) in fine pottery powder. Furthermore, the electron paramagnetic resonance (EPR) technique was used to study the firing temperature using the iron signal (Fe3+) as a firing temperature reference. The firing temperature of ceramics was found to be around 550 ± 50 °C.

    Palavras-Chave: ceramics; archaeological sites; thermoluminescence; age estimation; temperature dependence; photoluminescence; x-ray fluorescence analysis; cultural objects

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  • IPEN-DOC 29621

    PRADO, FELIPE M. ; FRANCO, TOMAS J. ; WETTER, NIKLAUS U. . Sub-nanosecond, 41 mJ pulse energy, passively Q-switched Nd:YLF laser. Optics and Laser Technology, v. 162, p. 1-6, 2023. DOI: 10.1016/j.optlastec.2023.109257

    Abstract: A sub-nanosecond, diode-stack side-pumped, passively Q-switched Nd3+:YLF4/Cr4+:YAG Laser is reported in a compact cavity design, generating one pulse of 41 mJ with a pulse width of 894 ps, achieving a peak output power of 46 MW and beam quality M2 of 5.4 × 5.9 (HxV). The number of pulses in the pulse train could be adjusted from one pulse to ten pulses of 111 mJ total output energy and 23.7 % optical efficiency by adjusting the focus distance while maintaining sub-nanosecond pulse duration. This resonator can also be used for high-power simultaneous Q-switched laser emission at 1047 nm and 1053 nm.

    Palavras-Chave: q-switching; high energy physics; crystals; pumping

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  • IPEN-DOC 29620

    AVELAR, ALAN M.; CAMARGO, FABIO de; SILVA, VANESSA S.P. da; GIOVEDI, CLAUDIA ; ABE, ALFREDO ; MOURAO, MARCELO B.. Effectiveness of Ni-based and Fe-based cladding alloys in delaying hydrogen generation for small modular reactors with increased accident tolerance. Nuclear Engineering and Technology, v. 55, n. 1, p. 156-168, 2023. DOI: 10.1016/j.net.2022.09.002

    Abstract: This study investigates the high temperature oxidation behaviour of a Ni–20Cr-1.2Si (wt.%) alloy in steam from 1200 °C to 1350 °C by Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS) and X-ray Diffraction (XRD). The results demonstrate that exposed Ni-based alloy developed a thin oxide scale, consisted mainly of Cr2O3. The oxidation kinetics obtained from the experimental results was applied to evaluate the hydrogen generation considering a simplified reactor core model with different cladding alloys following an unmitigated Loss-Of-Coolant Accident (LOCA) scenario in a hypothetical Small Modular Reactor (SMR). Overall, experimental data and simulations results show that both Fe-based and Ni-based alloys may enhance cladding survivability, delaying its melting, as well as reducing hydrogen generation under accident conditions compared to Zr-based alloys. However, a substantial neutron absorption occurs when Ni-based alloys are used as cladding for current uranium-dioxide fuel systems, even when compared to Fe-based alloys.

    Palavras-Chave: fuel-cladding interactions; nickel alloys; stainless steels; oxidation; temperature range 0400-1000 k; cladding

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  • IPEN-DOC 29619

    BORDON, CAMILA D. da S.; DIPOLD, JESSICA ; WETTER, NIKLAUS U. ; ROSSI, WAGNER de ; FREITAS, ANDERSON Z. ; KASSAB, LUCIANA R.P.. Effect of silver nanoparticles on the optical properties of double line waveguides written by fs laser in Nd3+-doped GeO2-PbO glasses. Nanomaterials, v. 13, n. 4, p. 1-13, 2023. DOI: 10.3390/nano13040743

    Abstract: Nd3+-doped GeO2-PbO glass with silver (Ag) nanoparticles (NPs) are produced with double line waveguides through fs laser processing for photonic applications. A Ti:sapphire fs laser at 800 nm was used to write the waveguides directly into the glass 0.7 mm beneath the surface. This platform is based on pairs of parallel lines with spacing of 10 µm, each pair being formed by two identical written lines but in two different configurations of 4 or 8 separately processed lines, which are coincident. The results of optical microscopy, absorbance measurements, refractive index change, beam quality factor (at 632 and 1064 nm), photoluminescence, propagation losses, and relative gain at 1064 nm are presented. The structural changes in the glass due to the presence of Ag NPs were investigated by Raman spectroscopy. At 632 and 1064 nm, x,y-symmetrical guiding was observed, and for both kinds of overlapping pulses, a refractive index alteration of 10−3 was found in both directions. Photoluminescence growth of ~47% at 1064 nm was observed due to the plasmonic effect of Ag NPs. In dual waveguides containing Ag NPs, the relative gain obtained increased by 40% and 30% for four and eight overlapping lines, respectively, at 600 mW of 808 nm pump power, when compared to waveguides without those metallic NPs. We highlight the resultant positive internal gains of 5.11 and 7.12 dB/cm that showed a growth of ~40% and ~30%, respectively, with respect to the samples without Ag NPs. The increase in photoluminescence and relative gain were related to the local field growth produced by Ag NPs. The present results show that the addition of Ag NPs impacts positively on the optical performance at 1064 nm of double line waveguides processed by fs laser writing in Nd3+-doped GeO2-PbO glass, opening news perspectives for photonics.

    Palavras-Chave: lasers; pulses; germanates; waveguides; optical equipment; silver; nanoparticles

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  • IPEN-DOC 29618

    MACHADO, ARTHUR P. ; CARMINATI, SAULO A. ; JANUARIO, ELIANE R. ; FERREIRA, PATRICIA S. ; VAZ, JORGE M. ; SPINACE, ESTEVAM V. . Photocatalytic methane conversion over Pd/ZnO photocatalysts under mild conditions. Methane, v. 2, n. 1, p. 44-55, 2023. DOI: 10.3390/methane2010003

    Abstract: Here, Pd nanoparticles supported on ZnO were prepared by the alcohol-reduction and the borohydride-reduction methods, and their efficiency towards the photocatalytic conversion of methane under mild conditions were evaluated. The resulting Pd/ZnO photocatalysts were characterized by X-ray fluorescence, X-ray diffraction, X-ray photoelectron spectroscopy, UV–Vis, and transmission electron microscopy. The reactions were performed with the photocatalysts dispersed in water in a bubbling stream of methane under UV-light illumination. The products formed were identified and quantified by gas chromatography (GC-FID/TCD/MSD). The principal products formed were C2H6 and CO2 with minor quantities of C2H4 and CO. No H2 production was observed. The preparation methods influenced the size and dispersion of Pd nanoparticles on the ZnO, affecting the performance of the photocatalysts. The best performance was observed for the photocatalyst prepared by borohydride reduction with 0.5 wt% of Pd, reaching a C2H6 production rate of 686 µmol·h−1·g−1 and a C2H6 selectivity of 46%.

    Palavras-Chave: photocatalysis; methane; zinc oxides; palladium; nanoparticles

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  • IPEN-DOC 29617

    SILVA, DANIEL J. da; FERREIRA, GREICIELE S.; DURAN, ADRIANA; FONSECA, FERNANDO L.A.; PARRA, DUCLERC F. ; BUENO, RODRIGO F.; ROSA, DERVAL S.. Copper coatings on poly(lactic acid) via rapid magnetron sputtering: morphology, chemistry, and antimicrobial performance against bacteria and SARS-CoV-2. Materials Today Communications, v. 34, p. 1-13, 2023. DOI: 10.1016/j.mtcomm.2023.105440

    Abstract: Materials with antimicrobial properties are highly desirable for making food packaging and personal protective equipment due to their intrinsic ability to prevent the proliferation of pathogenic microorganisms and food contamination. Poly(lactic acid) (PLA) is a biodegradable, compostable, and recyclable polymer that presents interesting mechanical properties for such applications. However, this polymer does not show intrinsic antimicrobial activity. Herein, we applied Radio Frequency Magnetron Sputtering (RF-MS) to produce antimicrobial copper coatings on the PLA surface. The results indicate that the prolongation in the copper deposition time causes an increase in surface roughness. The PLA coating with copper using a short deposition time (5–20 s) was sufficient to guarantee a bactericidal effect against Escherichia coli and Bacillus subtilis, in addition to conferring antiviral activity against Omicron Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Nuclear magnetic resonance (NMR) and high-resolution x-ray photoelectron (XPS) spectroscopic studies indicate that occurs only localized degradation on the PLA surface via polymer chain scission. The RF-MS technique was suitable for rapidly manufacturing antimicrobial Cu-coated PLA and providing low copper consumption in the antimicrobial coating process.

    Palavras-Chave: coronaviruses; polymers; lactic acid; copper; plasma; coatings; antimicrobial agents

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  • IPEN-DOC 29616

    KIM, BIANCA S.M.; AMORIM, EDUARDO P. ; SILVA, PAULO S.C. ; FIGUEIRA, RUBENS, C.L.; BRAGA, ELISABETE S.; FAVARO, DEBORAH I.T. . Vintage analysis on superficial sediments to predict future trends in metal contamination of Santos and São Vicente Estuarine System. Journal of Trace Elements and Minerals, v. 3, p. 1-8, 2023. DOI: 10.1016/j.jtemin.2023.100049

    Abstract: Due to its economic, social, and environmental importance, Santos and São Vicente Estuarine System is largely studied for almost two decades. Although many studies have been conducted, none of them tried to relate past activities to actual ones. This study provides an evaluation of the contamination on vintage superficial sediment samples investigating sediment contamination patterns over the years to help to understand future trends in metal contamination in this area. Thus, this study aims to assess levels of trace elements and rare earth elements (REEs) on samples collected in two seasonal periods of 2005 and 2006 (summer and winter). In each campaign, 16 surface samples were collected onboard R/V Veliger II, and trace elements and REEs were analyzed by neutron activation analysis. Results of metals presented similar levels over the years and it was not related to the port's activities since the levels did now increase following the total movement of containers. In addition, the enrichment of light REEs could indicate anthropogenic activities from steel plants, phosphate fertilizers, and the phosphogypsum piles. The system undergoes through many human pressures and constant monitoring over time it is important to avoid overloading the resilience capacity of the estuarine system because the expansion of port, industry, and urbanization is inevitable. From the results obtained, it was possible to conclude that SSVES undergoes more likely anthropogenic pressures from industrial activities and domestic effluents rather than port activity.

    Palavras-Chave: economic analysis; estuaries; water pollution; sediments; trace amounts; elements

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  • IPEN-DOC 29615

    RIBEIRO, I.L.F.; CARVALHO, G.L.; DIB, L.F.G.; BARBOSA, E.A.; WETTER, N.U. . Vibration amplitude mapping by stroboscopic structured light projection. Optics Communications, v. 531, p. 1-9, 2023. DOI: 10.1016/j.optcom.2022.129219

    Abstract: In this work a method to evaluate the distribution of vibration amplitudes of objects was demonstrated, combining for the first time oblique structured light projection, stroboscopic illumination and fringe evaluation. The light pattern was formed by straight and parallel fringes produced by a slightly misaligned Twyman–Green interferometer illuminated by a 40-mW, 650-nm diode laser. Stroboscopic illumination was achieved by driving the laser with a PWM signal with the same frequency than that of the vibrating object. By evaluating the fringes with phase stepping and phase unwrapping procedures, the amplitude mapping of a formica bar and circular rubber membranes was performed. By averaging the fringe position over the light pulse duration a correction ratio between the actual phase and the measured phase was obtained as a function of the pulse duty cycle, and the dependence of the fringe visibility on the duty cycle was studied. The experiments showed that relatively large amplitudes in a range from tens of millimeters up to few millimeters can be measured.

    Palavras-Chave: optical equipment; evaluation; vibrational states; mechanical vibrations

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  • IPEN-DOC 29614

    MELO, A.D.; SILVA, J.P. da; NOBRE, F.X.; COSTA, S.; SALES JUNIOR, J.C.C.; ANGLADA-RIVERA, J.; GUERRERO, F.; PAULA, M.M. da S.; SOUZA, R.F.B. de ; PENA-GARCIA R.; AGUILERA, L.; LEYET, Y.. Synthesis microwave-assisted: fast method to obtain lithium-doped sodium titanate. Journal of Materials Science: Materials in Electronics, v. 34, n. 6, p. 1-10, 2023. DOI: 10.1007/s10854-023-09948-w

    Abstract: In this work, the variation in the structural and electrical properties of lithium-doped sodium titanate, obtained from an ultrafast (15 min) microwave-assisted synthesis has been reported. X-ray diffraction and Rietveld analysis have been done to identify the present phases, their composition, and lattice parameters. Na2Ti3O7 was identified as the major phase, while Na2Ti6O13 was obtained as a secondary phase in all samples. The phase composition usually varies depending on the content of the doping element. In the sample with 0.5% lithium ions, an additional phase corresponding to NaLiTi3O7 appeared. The microstructure of the ceramic samples showed an increase in the grains size and the appearance of small particles on the surface of the grains. This effect becomes more evident for the samples with 0.5% Li. Finally, the electrical properties of the ceramic samples studied were favored with an increase in doping and σdc values of 1.94 × 10− 5 S cm− 1, 2.51 × 10− 5 S cm− 1, and 4.00 × 10− 5 S cm− 1 were determined for Na2 − xLixTi3O7 with x = 0.0%, 0.1%, 0.5% of Li+.

    Palavras-Chave: sodium compounds; titanates; microwave radiation; lithium; doped materials

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  • IPEN-DOC 29613

    PACHECO, CAROLINE V.; PERES, RENATO M.; CARRIERI, GABRIELA; MINUSSI, GIULIA R.; ZAMBRANA, GUIDO P.; KANG, JESSICA S.H.; OLIVEIRA, RENE R. de ; LIMA, NELSON B. de ; BERNUSSI, AYRTON; WARZYWODA, JULIUSZ; MUNHOZ, ANTONIO H.. Cement-based composites incorporating pseudoboehmite nanomaterials. Journal of Materials in Civil Engineering, v. 35, n. 2, p. 04022413-1 - 04022413-11, 2023. DOI: 10.1061/(ASCE)MT.1943-5533.0004586

    Abstract: Pseudoboehmite is a hydrated aluminum oxyhydroxide obtained from inorganic precursors by the sol-gel process. It is used as a precursor to alumina and as a reinforcement in obtaining nanocomposites. Cement-reinforced composites with this nanomaterial were obtained in concrete and mortar. Pseudoboehmite with sodium polyacrylate was used to promote a deflocculation of pseudoboehmite particles, which tend to agglomerate in the material. The obtained material was added to the concrete to improve its workability and strength. The new concrete was characterized by slump tests and mechanical tests. Our results revealed that the incorporation of pseudoboehmite with sodium polyacrylate significantly increased the compressive strength and improved the workability of the concrete. Multiple experiments evaluated compressive strength, ultrasound speed, and nanomaterial characterization. Using the Weibull method in mortars, we verified that the pseudoboehmite brought visible benefits as the characteristic stress increased by 17.5%. This increase was observed with the addition of 3% by weight of pseudoboehmite.

    Palavras-Chave: nanomaterials; aluminium compounds; building materials; mortars; concretes; sodium; polyacrylates

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  • IPEN-DOC 29612

    CANO, NILO F.; AYNAYA-CAHUI, SANDRA C.; VILCA, ZAIDA V.; ROCCA, RENE R.; GUNDU RAO, T.K.; CARRERA, BETZABEL N.S. ; LOPEZ-GONZALES, ALEJANDRO H.; JAVIER-CCALLATA, HENRY S.; AYALA-ARENAS, JORGE S.. Preparation and study of the main dosimetric properties by TL of sintered lithium silicate pellets. Journal of Luminescence, v. 255, p. 1-7, 2023. DOI: 10.1016/j.jlumin.2022.119580

    Abstract: This work presents the structural characteristics and the dosimetric properties under ionizing radiation of the lithium silicate (LSO) (LSO) phosphor. The structure of the synthesized material was determined by X-ray diffraction (XRD) method and Rietveld refinement method. The dosimetric properties of LSOLSO in the form of pellets were studied by thermoluminescence (TL) under the effect of different doses of γ-irradiation. The phosphor exhibited a TL emission curve with four TL peaks centered at 100, 182, 250 and 290 °C, with a light emission band centered at 385 nm. The TL dose-dependent γ-radiation dose response of the TL peak at 182 °C was linear in the low-dose region, from the order of mGy to 50 Gy. In addition, the phosphor exhibits lower fading, good reproducibility, and sensitivity of the order of commercial TLD-100 dosimeters.

    Palavras-Chave: lithium silicates; thermoluminescence; synthesis; dosimetry

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  • IPEN-DOC 29611

    CASTANHEIRA, BRUNA; BROCHSZTAIN, SERGIO; OTUBO, LARISSA ; TEIXEIRA, ANTONIO C.S.C.. Periodic mesoporous organosilicas containing naphthalenediimides as organic sensitizers for sulfadiazine photodegradation. Journal of Hazardous Materials, v. 443, n. Part B, p. 1-9, 2023. DOI: 10.1016/j.jhazmat.2022.130224

    Abstract: In this work, periodic mesoporous organosilicas (PMO) functionalized with the organic sentisizer naphthalenediimide (NDI) were employed as heterogeneous catalysts for the photodegradation of the antibiotic sulfadiazine (SDZ), taken as a model for contaminants of emerging concern (CECs). The catalysts, designated as PMONDI, were prepared by surfactant-directed co-condensation of the precursor N,N′-bis(3-triethoxysilylpropyl)− 1,4,5,8-naphthalenediimide with tetraethoxysilane. The synthesized PMONDI were characterized using transmission electron microscopy, nitrogen adsorption isotherms and small and large angle x-ray scattering. The performance of PMONDI catalysts in the photodegradation of SDZ was compared to that of TiO2 nanoparticles impregnated into SBA-15 mesoporous silica (TiO2/SBA-15), under irradiation with a Hg lamp with a bandpass filter of 320–500 nm. Under optimal conditions, PMONDI degraded 100% of the SDZ in 45 min, while the total degradation of SDZ was achieved only after 150 min with TiO2/SBA-15. PMONDI also performed better than TiO2/SBA-15 in reuse tests. The mechanism of photodegradation with PMONDI involves the formation of excited triplet states of NDI (3NDI*) upon irradiation, which can then react with molecular oxygen to form reactive oxygen species, which degrade SDZ. Analysis of the SDZ degradation products indicated two main pathways: (1) hydroxylation of the aniline ring and (2) SO2 extrusion and rearrangement, followed by oxidation of the aniline ring to nitrobenzene. In conclusion, the great potential of the PMONDI materials as photocatalysts for CECs degradation was demonstrated in this work, encouraging further research on these materials for the degradation of pollutants.

    Palavras-Chave: sulfonamides; pyrimidines; photocatalysis; naphthalene

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  • IPEN-DOC 29610

    MOREIRA, RENAN P. ; FRANCISCO, LEONARDO H.C. ; COSTA, ISRAEL F.; BARBOSA, HELLIOMAR P.; TEOTONIO, ERCULES E.S.; FELINTO, MARIA C.F.C. ; MALTA, OSCAR L.; BRITO, HERMI F.. Luminescence properties of BaMO4:Eu3+ (M: Mo or W) phosphors derived from co-precipitation reaction. Journal of Alloys and Compounds, v. 937, p. 1-11, 2023. DOI: 10.1016/j.jallcom.2022.168408

    Abstract: Luminescent BaMO4:xmol%Eu3+ materials (M: Mo or W, and x: 0, 2, 4, 6, 8, and 10 mol%) were successfully obtained by a coprecipitation method at room temperature without additional thermal treatment, leading to highly crystalline materials with reduced reaction times and low manufacturing cost. Structural analyses by powder X-ray diffraction and vibrational Raman techniques of the [WO4]2- and [MoO4]2- groups confirm a characteristic scheelite-type structure. The results indicate an average crystallite size at around 30 nm, and a highly pure phase has been supported by Rietveld refinement. SEM-EDS data of BaMO4:xmol%Eu3+ materials identified polycrystalline particles with bipyramidal-like morphology and homogeneous europium ion distribution. Additionally, the band gap energy (Eg) of barium molybdate and tungstate materials were calculated from reflectance data by the single-constant Kubelka-Munk function. Furthermore, the emission intensity, lifetime, and intrinsic emission quantum yield (Q Eu3+/Eu3+) of the materials have been determined and discussed. The luminescent properties of these materials are significantly influenced by the LMCT excitation bands (O2- → Mo6+, W6+, and Eu3+) as well as their intense red emission bands assigned to Eu3+ transitions. The experimental intensity parameter values Ω2 and Ω4 were evaluated from the emission spectra, using the magnetic dipole 5D0 → 7F1 transition as the standard reference. It was observed that the Ω2 values are much higher than the Ω4 values. This result is related to the fact that the 5D0 → 7F2 transition presents a much higher intensity than 5D0 → 7F1 one suggesting a low local symmetry around the Eu3+ ion, which might be due to angular distortions in the local coordination geometry. The high Q Eu3+/Eu3+ values (60–79%) indicated an overall high emission intensity for the prepared phosphors. These are special photonic features of the Eu3+-doped molybdate and tungstate, suggesting they could be suitable for luminescent materials applications.

    Palavras-Chave: luminescence; europium; tungstates; molybdates; coprecipitation; phosphors

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  • IPEN-DOC 29609

    PANESI, A.R.Q. ; SILVA, R.P. ; SANTIAGO, E.I. . Numerical validation of direct ethanol fuel cell operating at high temperature. Ionics, v. 29, n. 3, p. 1039-1052, 2023. DOI: 10.1007/s11581-022-04852-5

    Abstract: In the present work, a three-dimensional steady-state model was developed to analyze the performance of high-temperature direct ethanol fuel cell (HT-DEFC) based on polybenzimidazole (PBI) electrolytes. A non-isothermal model of a HT-DEFC setup using a PBI/H3PO4 membrane was employed using computational fluid dynamics (CFD). This work is aiming at a validation of experimental data of HT-DEFC prototypes based on the simulation of polarization curves. The model predicts the mole concentration of H3PO4, heat and current density distributions, as well as mass fraction ethanol during operation at 180 °C. The heat transfer model was coupled to the electrochemical and mass transport, allowing that a particular heating configuration was investigated considering the temperature distribution on the PBI membrane. We have found that temperature and relative humidity (RH) are mostly related to PBI properties resulting from H3PO4 lixiviation and conductivity decreasing as well as ethanol crossover strongly interferes on the oxygen reduction reaction (ORR) rate, leading to poor HT-DEFC performance.

    Palavras-Chave: phosphoric acid; ethanol; direct ethanol fuel cells; temperature dependence; benzimidazoles; computer calculations; fluid mechanics

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  • IPEN-DOC 29608

    GENESI, BIANCA P.; BARBOSA, RAQUEL de M.; SEVERINO, PATRICIA; RODAS, ANDREA C.D.; YOSHIDA, CRISTIANA M.P.; MATHOR, MONICA B. ; LOPES, PATRICIA S.; VISERAS, CESAR; SOUTO, ELIANA B.; SILVA, CLASSIUS F. da. Aloe vera and copaiba oleoresin-loaded chitosan films for wound dressings: microbial permeation, cytotoxicity, and in vivo proof of concept. International Journal of Pharmaceutics, v. 634, p. 1-12, 2023. DOI: 10.1016/j.ijpharm.2023.122648

    Abstract: Chitosan films are commonly used for wound dressing, provided that this polymer has healing, mucoadhesiveness and antimicrobial properties. These properties can be further reinforced by the combination of chitosan with polysaccharides and glycoproteins present in aloe vera, together with copaiba oleoresin’s pharmacological activity attributed to sesquiterpenes. In this work, we developed chitosan films containing either aloe vera, copaiba oil or both, by casting technique, and evaluated their microbial permeation, antimicrobial activity, cytotoxicity, and in vivo healing potential in female adult rats. None of the developed chitosan films promoted microbial permeation, while the cytotoxicity in Balb/c 3 T3 clone A31 cell line revealed no toxicity of films produced with 2 % of chitosan and up to 1 % of aloe vera and copaiba oleoresin. Films obtained with either 0.5 % chitosan or 0.5 % copaiba oleoresin induced cell proliferation which anticipate their potential for closure of wound and for the healing process. The in vivo results confirmed that tested films (0.5 % copaiba-loaded chitosan film and 0.5 % aloe vera-loaded chitosan film) were superior to a commercial dressing film. For all tested groups, a fully formed epithelium was seen, while neoformation of vessels seemed to be greater in formulations-treated groups than those treated with the control. Our work confirms the added value of combining chitosan with aloe vera and copaiba oil in the healing process of wounds.

    Palavras-Chave: medicinal plants; trees; polysaccharides; glycoproteins; wounds; healing

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  • IPEN-DOC 29607

    MARTINS, LUCIANE; LESSA, LUIS G.F.; ALI, TACCYANNA M.; LAZAR, MONIZE; KIM, CHONG A.; KANTOVITZ, KAMILA R.; SANTAMARIA, MAURO P.; ARAUJO, CASSIA F.; RAMOS, CAROLINA J.; FOSTER, BRIAN L.; FRANCO, JOSE F.S. ; BERTOLA, DEBORA; NOCITI JUNIOR, FRANCISCO H.. Childhood hypophosphatasia associated with a novel biallelic ALPL variant at the TNSALP dimer interface. International Journal of Molecular Sciences, v. 24, n. 1, p. 1-10, 2023. DOI: 10.3390/ijms24010282

    Abstract: The goal of this study was to perform a clinical and molecular investigation in an eight-year-old female child diagnosed with hypophosphatasia (HPP). The proband and her family were evaluated by medical and dental histories, biochemical analyses, radiographic imaging, and genetic analysis of the tissue-nonspecific alkaline phosphatase (ALPL) gene. A bioinformatic analysis was performed to predict the structural and functional impact of the point mutations in the tissue-nonspecific alkaline phosphatase (TNSALP) molecule and to define their potential contribution to the phenotype. We identified a novel combination of heterozygous ALPL missense variants in the proband, p.Ala33Val and p.Asn47His, compatible with an autosomal recessive mode of inheritance and resulting in skeletal and dental phenotypes. Computational modeling showed that the affected Asn47 residue is located in the coil structure close to the N-terminal α-helix, whereas the affected Ala33 residue is localized in the N-terminal α-helix. Both affected residues are located close to the homodimer interface, suggesting they may impair TNSALP dimer formation and stability. Clinical and biochemical follow-up revealed improvements after six years of ERT. Reporting this novel combination of ALPL variants in childhood HPP provides new insights into genotype–phenotype associations for HPP and specific sites within the TNSALP molecule potentially related to a childhood-onset HPP and skeletal and dental manifestations. Beneficial effects of ERT are implicated in skeletal and dental tissues.

    Palavras-Chave: genotype; phenotype; alkaline phosphatase; hereditary diseases; dentistry; teeth; children; 3d printing

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  • IPEN-DOC 29606

    CAMANI, PAULO H.; MIDHUN DOMINIC, C.D.; PARRA, DUCLERC F. ; MALTEZ, HELOISA F.; ROSA, DERVAL S.. Divalent metal ion removal from simulated water using sustainable starch aerogels: effect of crosslinking agent concentration and sorption conditions. International Journal of Biological Macromolecules, v. 226, p. 628-645, 2023. DOI: 10.1016/j.ijbiomac.2022.11.308

    Abstract: This paper evaluates corn starch aerogels, studying different crosslinking agent (trisodium citrate) concentrations (1:1, 1:1.5, and 1:2) and sorption conditions (contact time, adsorbent weight, and initial concentration) regarding the potentially toxic elements (PTEs) [Cd(II) or Zn(II)] adsorption of the aqueous systems. Besides, other properties of aerogels, such as structural properties, specific surface area, and mechanical performance, were evaluated. For adsorption results, better values were observed in adsorption capacity and efficiency for the initial concentration of 100 ppm. In addition, an adsorption time of 12 h and an adsorbent weight of 3.0 g obtained better results due to the possible balance in this time and the high specific surface area available for Cd(II) adsorption. As for the type of adsorbent, the Aero 1:1.5 sample (intermediate crosslinking agent concentration) obtained better results, possibly due to the high porosity, smaller pore sizes, high pore density, and high specific surface area (198 m2·g−1). In addition, hydroxyl groups in the starch aerogel removed Cd(II) ions with 30 % adsorption efficiency. Lastly, Aero 1:1.5 obtained a high mechanical strength at compression and a satisfactory compressive modulus. In contrast, starch aerogels did not absorb the Zn(II) ion.

    Palavras-Chave: maize; starch; gels; adsorption; elements; toxic materials

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  • IPEN-DOC 29605

    MAIA, VICTORIA A. ; SANTOS, CAMILA M.G. ; AZEREDO, NATHALIA F.B. ; ZAMBIAZI, PRISCILLA J. ; ANTOLINI, ERMETE; NETO, ALMIR O. ; SOUZA, RODRIGO F.B. de . Conversion of nitrogen to ammonia using a Cu/C electrocatalyst in a polymeric electrolyte reactor. Electrochemistry Communications, v. 146, p. 1-4, 2023. DOI: 10.1016/j.elecom.2022.107421

    Abstract: The electrochemical conversion of N2 to NH3 using a polymeric electrolyte reactor is a promising method to accelerate the green production of hydrogen carriers. On this basis, we report the efficiency of ammonia production by the nitrogen reduction reaction using a Cu/C catalyst in a polymeric electrolyte membrane reactor. The Cu/C catalyst was prepared by the NaBH4 reduction method and characterized by X-ray diffraction, transmission electron microscopy, cyclic voltammetry, and conversion experiments performed in a polymer electrolyte membrane fuel cell type reactor. The X-ray diffraction results showed the presence of CuO2 and carbon phases, while the TEM images showed a high agglomeration of copper nanoparticles on carbon. The onset potential of nitrogen reduction was near to the Cu (I) to Cu0 reduction peak. Mass spectroscopy was used to observe the production of N2H2 and NH3 and the consumption of N2. Maximum ammonia production was detected at 0.0 V with a NH3 yield rate of 38.4 µg h−1 cm−2 and a faradaic efficiency of 42.57 %.

    Palavras-Chave: nitrogen; reduction; ammonia; electrolytic cells; nuclear fuels; fuel cells; copper; carbon; catalysts

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  • IPEN-DOC 29604

    GUIMARAES, VITORIA P.; NANDENHA, JULIO ; ORZARI, LUIZ O.; FATIBELLO-FILHO, ORLANDO; OLIVEIRA NETO, ALMIR ; JANEGITZ, BRUNO C.; VICENTINI, FERNANDO C.; ASSUMPCAO, MONICA H.M.T.. Effect of TiO2 and synthesis strategies on formate oxidation: electrochemical and fuel cell approaches. Electrocatalysis, v. 14, n. 2, p. 221-231, 2023. DOI: 10.1007/s12678-022-00789-5

    Abstract: Direct formate fuel cells have gained increasing attention since formate can be obtained by CO2 reduction, being shown as a renewable power source. This paper reports the use of Pd nanoparticles supported on physical mixtures of Vulcan carbon and TiO2 in different ratios and different Pd reduction methodologies. The materials were prepared using sodium borohydride as a reducing agent and analyzed toward formate oxidation in alkaline media. The prepared electrocatalysts showed peaks of Pd face-centered cubic and TiO2 anatase and rutile phases and an average particle size between 3.7 and 7.9 nm. Experiments considering formate electro-oxidation (voltammetry and chronoamperometry) showed that the presence of TiO2 is favorably using both synthesis methodologies while single cells revealed Pd nanoparticles supported on physical mixtures of carbon and TiO2, in the proportion of 75:25 as the most efficient, which was explained by the carbon high electrical conductivity and small quantities of TiO2 working as co-catalyst.

    Palavras-Chave: palladium; nanoparticles; titanium oxides; oxidation; formate fuel cells

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  • IPEN-DOC 29603

    FONSECA, E.B.; FATICHI, A.Z.; TERADA, M.; BUGARIN, A.F.S. ; RODRIGUEZ, J.; COSTA, ISOLDA ; RAMIREZ, A.J.. Quantitative analysis of susceptibility to intergranular corrosion in alloy 625 joined by friction stir welding. Corrosion Engineering, Science and Technology, v. 58, n. 2, p. 138-144, 2023. DOI: 10.1080/1478422X.2022.2152174

    Abstract: Alloy 625 is a Ni-based alloy used in aerospace, energy, chemical, oil and gas industries, mainly as cladding material due to its corrosion resistance, high strength and creep resistance at high temperature. In this study, microstructural evaluation and susceptibility to intergranular corrosion of base metal and friction stir welded Alloy 625 were investigated. Friction stir welded joints exhibited a lower corrosion rate and degree of sensitisation compared to the base metal. It is mainly due to grain refinement and lower cooling rate of the friction stir welding process. The stir zone of the present weld has a finer grain structure and lower density of twin boundaries than the base metal and it led to the improvement of the mechanical and corrosion properties.

    Palavras-Chave: inconel 625; nickel base alloys; intergranular corrosion; friction welding; microstructure; microhardness

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  • IPEN-DOC 29602

    LOPES, ISABELA S.; CASSAS, FERNANDO; VEIGA, THIAGO A.M.; SILVA, FLAVIA R. de O. ; COURROL, LILIA C.. Synthesis and characterization of Eugenia uniflora L. silver nanoparticles and L-cysteine sensor application. Chemistry and Biodiversity, v. 20, n. 1, p. 1-12, 2023. DOI: 10.1002/cbdv.202200787

    Abstract: L-Cysteine (Cys) is a non-essential sulfur-containing amino acid, crucial for protein synthesis, detoxification, and several metabolic functions. Cys is widely used in the agricultural, food, cosmetic, and pharmaceutical industries. So, a suitable sensitive and selective sensing approach is of great interest, and a low-cost sensor would be necessary. This article presents silver nanoparticles (EuAgNPs) synthesized by a green synthesis method using Eugenia uniflora L. extracts and photoreduction. The nanoparticles were characterized by UV/VIS, transmission electron microscopy, high-performance liquid chromatography (HPLC), FTIR, and Zeta potential. With the addition of Cys in the EuAgNPs solution, the terminal thiol part of L-cysteine binds on the surface of nanoparticles through Ag−S bond. The EuAgNPs and CysAgNPs coexist until flavonoids bound the amino group of Cys, enhancing the red color of solutions. The EuAgNPs provided selectivity to detect Cys among other amino acids, and its detection limit was found to be 3.8 nM. The sensor has the advantages of low-cost synthesis, fast response, high selectivity, and sensitivity.

    Palavras-Chave: trees; cysteine; amino acids; silver; nanoparticles; photochemistry; reduction

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  • IPEN-DOC 29601

    LIMA, ELIANA R. ; FREIRE, RENAN P. ; SUZUKI, MIRIAM F. ; OLIVEIRA, JOAO E. ; YOSIDAKI, VANESSA L. ; PERONI, CIBELE N. ; SEVILHANO, THAIS ; ZORZETO, MOISES; TORATI, LUCAS S.; SOARES, CARLOS R.J. ; LIMA, IGOR D. de M.; KRONENBERGER, THALES; MALTAROLLO, VINICIUS G.; BARTOLINI, PAOLO . Isolation and characterization of the Arapaima gigas growth hormone (ag-GH) cDNA and three-dimensional modeling of this hormone in comparison with the human hormone (hGH). Biomolecules, v. 13, n. 1, p. 1-17, 2023. DOI: 10.3390/biom13010158

    Abstract: In a previous work, the common gonadotrophic hormone α-subunit (ag-GTHα), the ag-FSH β- and ag-LH β-subunit cDNAs, were isolated and characterized by our research group from A. gigas pituitaries, while a preliminary synthesis of ag-FSH was also carried out in human embryonic kidney 293 (HEK293) cells. In the present work, the cDNA sequence encoding the ag-growth hormone (ag-GH) has also been isolated from the same giant Arapaimidae Amazonian fish. The ag-GH consists of 208 amino acids with a putative 23 amino acid signal peptide and a 185 amino acid mature peptide. The highest identity, based on the amino acid sequences, was found with the Elopiformes (82.0%), followed by Anguilliformes (79.7%) and Acipenseriformes (74.5%). The identity with the corresponding human GH (hGH) amino acid sequence is remarkable (44.8%), and the two disulfide bonds present in both sequences were perfectly conserved. Three-dimensional (3D) models of ag-GH, in comparison with hGH, were generated using the threading modeling method followed by molecular dynamics. Our simulations suggest that the two proteins have similar structural properties without major conformational changes under the simulated conditions, even though they are separated from each other by a >100 Myr evolutionary period (1 Myr = 1 million years). The sequence found will be used for the biotechnological synthesis of ag-GH while the ag-GH cDNA obtained will be utilized for preliminary Gene Therapy studies.

    Palavras-Chave: fishes; pituitary hormones; gonadotropins; molecules; cloning; dna sequencing

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  • IPEN-DOC 29600

    FREIRE, RENAN P. ; HERNANDEZ-GONZALEZ, JORGE E.; LIMA, ELIANA R. ; SUZUKI, MIRIAM F. ; OLIVEIRA, JOAO E. de ; TORATI, LUCAS S.; BARTOLINI, PAOLO ; SOARES, CARLOS R.J. . Molecular cloning and AlphaFold modeling of thyrotropin (ag-TSH) from the Amazonian fish Pirarucu (Arapaima gigas). Bioinformatics and Biology Insights, v. 17, p. 1-13, 2023. DOI: 10.1177/11779322231154148

    Abstract: Arapaima gigas, known as Pirarucu in Brazil, is one of the largest freshwater fish in the world. Some individuals could reach 3 m in length and weight up to 200 kg. Due to extinction risks and its economic value, the species has been a focus for preservation and reproduction studies. Thyrotropin (TSH) is a glycoprotein hormone formed by 2 subunits α and β whose main activity is related to the synthesis of thyroid hormones (THs)—T3 and T4. In this work, we present a combination of bioinformatics tools to identify Arapaima gigas βTSH (ag-βTSH), modeling its molecular structure and express the recombinant heterodimer form in mammalian cells. Using the combination of computational biology, based on genome-related information, in silico molecular cloning and modeling led to confirm results of the ag-βTSH sequence by reverse transcriptase-polymerase chain reaction (RT-PCR) and transient expression in human embryonic kidney (HEK293F) cells. Molecular cloning of ag-βTSH retrieved 146 amino acids with a signal peptide of 21 amino acid residues and 6 disulfide bonds. The sequence has a similarity to 39 fish species, ranging between 43.1% and 81.6%, whose domains are extremely conserved, such as cystine knot motif and N-glycosylation site. The Arapaima gigas thyrotropin (ag-TSH) model, solved by AlphaFold, was used in molecular dynamics simulations with Scleropages formosus receptor, providing similar values of free energy ΔGbind and ΔGPMF in comparison with Homo sapiens model. The recombinant expression in HEK293F cells reached a yield of 25 mg/L, characterized via chromatographic and physical-chemical techniques. This work shows that other Arapaima gigas proteins could be studied in a similar way, using the combination of these techniques, recovering more information from its genome and improving the reproduction and preservation of this prehistoric fish.

    Palavras-Chave: fishes; thyroid hormones; tsh; molecules; cloning; toxicity

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  • IPEN-DOC 29599

    NEGAHDARY, MASOUD; HIRATA, MARIO H.; SAKATA, SOLANGE K. ; CICONELLI, ROZANA M.; BASTOS, GISELE M.; BORGES, JESSICA B.; THUROW, HELENA S.; SILVEIRA JUNIOR, ALCEU T.; SAMPAIO, MARCELO F.; GUIMARAES, LARISSA B.; MAEDA, BRUNO S.; ANGNES, LUCIO. Sandwich-like electrochemical aptasensing of heat shock protein 70 kDa (HSP70): application in diagnosis/prognosis of coronavirus disease 2019 (COVID-19). Analytica Chimica Acta, v. 1242, p. 1-10, 2023. DOI: 10.1016/j.aca.2022.340716

    Abstract: In this research, by using aptamer-conjugated gold nanoparticles (aptamer-AuNPs) and a modified glassy carbon electrode (GCE) with reduced graphene oxide (rGO) and Acropora-like gold (ALG) nanostructure, a sandwich-like system provided for sensitive detection of heat shock protein 70 kDa (HSP70), which applied as a functional biomarker in diagnosis/prognosis of COVID-19. Initially, the surface of the GCE was improved with rGO and ALG nanostructures, respectively. Then, an aptamer sequence as the first part of the bioreceptor was covalently bound on the surface of the GCE/rGO/ALG nanostructures. After adding the analyte, the second part of the bioreceptor (aptamer-AuNPs) was immobilized on the electrode surface to improve the diagnostic performance. The designed aptasensor detected HSP70 in a wide linear range, from 5 pg mL−1 to 75 ng mL−1, with a limit of detection (LOD) of ∼2 pg mL−1. The aptasensor was stable for 3 weeks and applicable in detecting 40 real plasma samples of COVID-19 patients. The diagnostic sensitivity and specificity were 90% and 85%, respectively, compared with the reverse transcription-polymerase chain reaction (RT-PCR) method.

    Palavras-Chave: gold; nanomaterials; coronaviruses; electrochemistry; electrodes; graphene

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  • IPEN-DOC 29598

    AZEVEDO, JULIANA S.; BRAGA, ELISABETE S.; KUNIYOSHI, LEONARDO S.; FAVARO, DEBORAH I.T. . Seasonal arsenic in catfish (Siluriformes, Ariidae) and the hydrochemical conditions of two areas in a Ramsar site on the Brazilian coast. Anais da Academia Brasileira de Ciências, v. 95, n. 2, p. 1-11, 2023. DOI: 10.1590/0001-3765202320210033

    Abstract: The construction of a data bank concerning metal and metalloid content of bioindicator fish from coastal areas is very important as it can help environmental managers in decision making. In natural conditions, the concentration of elements can be influenced by abiotic parameters such as water salinity. In this study, catfish Cathorops spixii were evaluated concerning the total arsenic (As) concentration in the muscle tissues of individuals subjected to different abiotic conditions in the Cananéia-Iguape Estuarine-Lagoon Complex (CIELC), which was recently included on the Ramsar list of wetlands of international importance. Seventy-four catfish were seasonally caught in the northern and southern regions of the CIELC and their hydrochemical parameters were obtained. C. spixii from the southern, best preserved, area showed arsenic concentrations around ten times higher than the maximum limit established for fish intended for human consumption. However, these high concentrations of arsenic could be associated with the abiotic parameters of the water, such as salinity variations, in this area.

    Palavras-Chave: fishes; arsenic; estuaries; environmental protection; salinity

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  • IPEN-DOC 29597

    CARVALHO, SABRINA G.M. ; MUCCILLO, ELIANA N.S. ; MUCCILLO, REGINALDO . Design and validation of an experimental setup for evaluation of gas permeation in ceramic membranes. Membranes, v. 13, n. 2, p. 1-12, 2023. DOI: 10.3390/membranes13020246

    Abstract: An experimental setup for the evaluation of permeation of gaseous species with the possibility of simultaneously collecting electrochemical impedance spectroscopy data in disk-shaped ceramic membranes was designed and assembled. It consists of an alumina sample holder with thermocouple tips and platinum electrodes located close to both sides of the sample. Water-cooled inlet and outlet gas connections allowed for the insertion of the sample chamber into a programmable split tubular furnace. Gas permeation through a ceramic membrane can be monitored with mass flow controllers, a mass spectrometer, and an electrochemical impedance analyzer. For testing and data validation, ceramic composite membranes were prepared with the infiltration of molten eutectic compositions of alkali salts (lithium, sodium, and potassium carbonates) into porous gadolinia-doped ceria. Values of the alkali salt melting points and the permeation rates of carbon dioxide, in agreement with reported data, were successfully collected.

    Palavras-Chave: ceramics; membranes; carbon dioxide; permeability

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  • IPEN-DOC 29596

    SANTOS, PAULO R.S.; JESUS, ASHELY A.S.S. de; LIMA, WILLIAM B. de; COSTA, ISRAEL F.; FAUSTINO, WAGNER M.; FELINTO, MARIA C.F.C. ; TEOTONIO, ERCULES E.S.; BRITO, HERMI F.. Complex of luminescent europium containing bis(diphenylphosphine)oxide ligands. In: SILVA, FERNANDO de C. da (Org.) REUNIAO ANUAL DA SBQ, 45., 31 de maio - 3 de junho, 2022, Maceió, AL. Resumo... São Carlos, SP: Aptor Software, 2022. p. 380-380.

    Abstract: Trivalent lanthanide coordination compounds are characterized by their long luminescence lifetime of emitting level, narrow emission band and high color purity, which makes them fascinate for application in LCMDs, OLEDs, immunoassay, bioimaging probes, luminescent sensors and in telecommunications systems etc. Among this class of compounds, those ones in which β-diketonate ligands act as luminescence sensitizers have found a prominent position. However, most of these systems are obtained in the form of simple molecular entities. Recently, interest in new polynuclear systems containing diketonate ligands has been growing significantly. Therefore, this work reports on the synthesis, characterization, and photophysical properties of the lanthanide compounds of general formula [Ln2(β- dik)6(dppeO2)], where β-dik = tta, bzac, dbm, [Ln(β-dik)3(dppeO2)] where β-dik = btf and [Ln(β-dik)3(dppeO2)2]n where β-dik = fod, dppeO2 = 1,2-Bis(diphenylphosphino)ethane oxide, Ln = Eu3+ and Gd3+. These complexes were prepared by direct reaction among ethanolic solutions of the [Ln(β-dik)3(H2O)] complexes and dppeO2 ligands in the molar ratios [Ln(β-dik)3(H2O)]: dppeO2 of 2:1. The FT-IR spectra of complexes show red-shifted of 20–41 cm-1 for the band assigned to the ν(C=O) vibrational mode (Fig 1a), suggesting that β–diketonate ligands are coordinated to the Ln3+ ion in chelating mode. Diffuse reflectance spectra of the Eu3+-complexes show strong absorption bands in the range of 200–450 nm ascribed to the S0→Sn (ππ* or mixed nπ*) transitions from the diketonate ligands. The high relative intensities between excitation bands from ligand and 4f-4f transitions in the complexes with tta, btf and bzac indicates an efficient ligand-to-metal energy transfer process. On the other hand, for complexes with fod, dbm and bzac (Fig 1b) a lower intensity of the ligand bands is observed, suggesting that a luminescence suppression channel is operative. The emission spectra present the bands assigned to the 5D0→7FJ (J = 0–4) transitions of the europium ion (Fig 1c). The Ω2 and Ω4 intensity parameters, lifetime (τ) and luminescence intrinsic quantum yield ΦEu/Eu were calculated from the emission spectral data and luminescence decay curves of the compounds in solid state (Table 1). According with these data, the polymeric or dimeric investigated systems exhibit high luminescence intensities in the red region, which make them potential candidates for application as emitting layer in molecular light-converting devices.

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  • IPEN-DOC 29595

    SAULA, MATHEUS S.N.; FELINTO, MARIA C.F.C. ; NUNES, LUIZ A.O.; MALTA, OSCAR L.; BRITO, HERMI F.. Europium activator ion acting as an efficient luminescent probe to identify local symmetry in Li2ZnSn3O8:Eu3+ materials prepared by the MASS method. In: SILVA, FERNANDO de C. da (Org.) REUNIAO ANUAL DA SBQ, 45., 31 de maio - 3 de junho, 2022, Maceió, AL. Resumo... São Carlos, SP: Aptor Software, 2022. p. 390-390.

    Abstract: Luminescent materials doped with rare earth ions (RE) have been intensely applied in several areas in the new photonic technologies, such as emergency lights, radiation detectors, biological markers, and anti-counterfeiting products. Stannate-based host matrices have attracted significant attention, as they are relatively inexpensive and have a favorable bandgap to allow the persistence luminescence phenomenon. In this work, Li2ZnSn3O8:Eu3+ was synthesized by the microwave-assisted solid-state method (MASS) using a domestic microwave oven after gridding Li2CO3, ZnO, SnO2, Eu2O3 precursor oxides. Therefore, the as-prepared precursors were heated in a static air atmosphere at a preset configuration of 900W for 20 min. The material was characterized by powder X-ray diffraction (PXRD), scan electron microscopy (SEM), and diffused reflectance spectroscopy. The PXRD patterns indicate the formation of the desired Li2ZnSn3O8matrix phase when doped with different concentrations of the Eu3+ ion, showing a high crystallinity. The photoluminescence properties were determined based on the emission spectra of the Li2ZnSn3O8:mol%Eu3+ materials (Fig 1), showing intense yellowish-orange and reddish-orange emission colors under UV excitation at 282 and 336 nm, respectively. Moreover, both spectra show narrow emission bands characteristic of 5D0 →7F0-4 Eu3+ transitions. Sinceeuropium ions are powerful spectroscopic probes for the symmetry of the first coordination sphere of these ions in a lattice, and the spectral profiles change with the incident radiation wavelengths, which demonstrates the presence of more than one site of symmetry around the chemical environment of the Eu3+ion.Finally, it is noteworthy that these luminescent materials can be selectively excited in the UV range, leading to more than one specific emission spectral profile, which can be applied as efficient luminescent probes for anti-counterfeiting products.

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  • IPEN-DOC 29594

    COSTA, ISRAEL F.; BLOIS, LUCCA; SANTOS, PAULO R.; CARNEIRO NETO, ALBANO N.; MOURA JUNIOR, RENALDO T.; DEFLON, VICTOR M.; CARLOS, LUIS D.; FAUSTINO, WAGNER M.; FELINTO, MARIA C.F.C. ; LONGO, RICARDO L.; MALTA, OSCAR L.; TEOTONIO, ERCULES E.S.; BRITO, HERMI F.. Unexpected luminescent and thermal properties of novel tetrakis Eu3+- indandionate complex: experimental and theoretical studies. In: SILVA, FERNANDO de C. da (Org.) REUNIAO ANUAL DA SBQ, 45., 31 de maio - 3 de junho, 2022, Maceió, AL. Resumo... São Carlos, SP: Aptor Software, 2022. p. 437-437.

    Abstract: Luminescent coordination compounds based on trivalent europium ions (Eu3+) have found wide range of applications in new technologies, such as optoelectronics, molecular thermometers, and biomedical devices. Applications of this materials may be associated with narrow emission bands, which are arise from intra-configurational Laporte forbidden 4f – 4f transitions (5D0 → 7FJ). Furthermore, Eu3+ ion can act as a powerful spectroscopic probe and the 5D0 → 7F2 transition are strongly sensitive to small angular variations in the coordination polyhedron. However, the energy structures of the organic ligands in the complexes play the most important role on the Eu3+ luminescence sensitization process1. In this context, this work reports about theoretical, syntheses, characterization, and photoluminescence studies of a series of tetrakis complexes containing tetraethylammonium, Et4N+[Ln(L)4]– (Et4N+: tetraethylammonium cation, Ln: Gd and Eu, and L: 2-acyl-1,3-indandionate). The Judd–Ofelt intensity parameter (Ωλ), lifetime (τ), radiative (Arad) and non-radiative (Anrad) coefficients, and intrinsic quantum yield ΩEu/Eu) values were calculated for different temperatures (80 - 475 K) (Table 1). The Et4N+[Eu(isovind)4]– complex, where isovind: 2-isovaleryl-1,3-indandonate) shows an extraordinarily high value of the intensity parameter (Ω2 = 73.5×10-20 cm2, considering the index of refraction equal to 1.5) and radiative decay rate (Arad = 2.468×103 s-1) at 300 K. These optical results show an abnormally high emission intensity of the 5D0 → 7F2 transition (Figure 1), leading to the highest measured Ω2 value of the europium materials, to the best our knowledge, reported in the literature. In addition, this complex shows different solid phases at 367 and 460 K, leading significant changes in the band profile assigned to the 5D0 → 7F2 transition. The spectroscopic study of luminescent systems has shown very interesting and promising results for applications, such as OLED devices and luminescent thermometers based on Ln3+ ions.

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  • IPEN-DOC 29593

    FELINTO, MARIA C.F.C. ; SILVA, JAQUELINE A.P. ; FRANCISCO, LEONARDO C. ; COSTA, ISRAEL F.; TEOTONIO, ERCULES E.S.; MALTA, OSCAR M.L.; BRITO, HERMI F.. Preparation and photoluminescence properties of functionalized silica submicron-sphere materials decorated with Eu(tta)3•FX complex (FX= fluoxetin). In: SILVA, FERNANDO de C. da (Org.) REUNIAO ANUAL DA SBQ, 45., 31 de maio - 3 de junho, 2022, Maceió, AL. Resumo... São Carlos, SP: Aptor Software, 2022. p. 511.

    Abstract: The development of functionalized silica particles containing luminescent materials has received special attention because of their biological applications such as optical markers in vitro and in vivo, clinical diagnosis and drug delivery. The incorporation of Eu3+-complex into modified silica particles combines optical characteristics of Eu3+- complex and properties of inorganic oxides, resulting in organic-inorganic hybrid materials. In this work, we synthesize and characterize sub-microspheres of SiO2 decorated with a new complex of Eu3+ and fluoxetine, an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. The Eu-complex and the submicron-spheres (ϕ~500nm) were characterized optically and photo-physical characteristics of these materials were examined spectroscopically. In emission spectra of complex (Fig 1.a), four characteristic peaks of Eu3+ ion with the maximum at ~580 nm, ~595 nm, ~614 nm, and ~702 nm accredited to 5D0 → 7FJ (J = 0-4) transitions appeared upon excitation in UV region. The most intense peak at 614 nm is accountable for the bright red emission of the ternary complex. For the SiO2 nanospheres decorated with the complex these transitions are close to the complex but are identified the change in the symmetry around the Eu3+ ion when analyzing the spectra. Experimental intensity parameters (Ωλ), lifetime (τ), radiative (Arad) and non-radiative (Anrad) coefficients, and intrinsic quantum yield (Q Eu3+/Eu3+) values were determined. 3D emission spectra for the Eu(tta)3•FX complex in the VUV region (Fig. 1b) revealed a high emission band originated from (Eu3+) 5D0→7F2,4 transitions (centered around 614 and 702nm) under excitation at near bandgap energy. Color purity and CIE parameters also suggest the red luminous behavior of complex. Thermal and morphological behavior of the Eu-complex and submicron-spheres decorated with the Eu(tta)3•FX complex are also evaluated (Fig1c). Our investigation has revealed that the synthesized complex and inorganic hybrid materials could be used in preparing lighting systems, OLEDs, display devices and biological sensors owing to their luminescent characteristics

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  • IPEN-DOC 29592

    SANTOS, SIMEI T.S.; BRITO, HERMI F.; TEOTONIO, HERCULES E.S.; FELINTO, MARIA C.F.C. ; MALTA, OSCAR L.. Synthesis, modification surface and characterization of tungstate/molybdate of zinc, doped with lanthanide ions [ Zn1-xREx(WO4)y(MoO4)z] (y or z = 0, 0.5, 1). In: SILVA, FERNANDO de C. da (Org.) REUNIAO ANUAL DA SBQ, 45., 31 de maio - 3 de junho, 2022, Maceió, AL. Resumo... São Carlos, SP: Aptor Software, 2022. p. 535-535.

    Abstract: A class of materials with the general formulation of MIMIII(XO4)2 (MI=Alkali metal, MIII = trivalente metal and X = W or Mo) with structural importance and diferente properties exposed to the attention of researchers, especially when doped with rare earth ions, which give the material luminescent properties. These properties can make the material promisingly important for diverse applications, such as solar cells, light converting devices and sensors, depending only on the changes in its structure and surface. This work was synthesized using co-precipitation method from aqueous solutions tungstates and molybdates of zinc doped with rare earth íons (Scheme 1a [Zn0.95Eu0.05WO4],1b [Zn0.95Eu0.05(WO4)0.5(MoO4)0.5],1c [Zn0.95Eu0.025Tb0.025WO4]) and coated with a thin layer of sílica (scheme 1d) using the hydrolysis and condensation of tetraethoxysilane (TEOS). For the phenantroline ligand functionalization, 3- (chloropropyl)triethoxy-silane (CPES) was grafted onto the particle surfaces in their aqueous suspensions, and bound to modified phenanthroline. For the synthesis of doped tungstates and molybdates, equivalent amounts of zinc, terbium, and europium chlorides were added under stirring at 70 °C for 1h. After drying, the material was ground with TEOS, water, ethanol and remained (with catalyze acid) for 3h at 70 °C under constant agitation. The 1,10- Phenantroline (scheme 1e) has been nitrated (H2SO4/HNO3) (scheme 1f) and reduced (Sn/HCl) (scheme 1g and infrared) to then be coupled to the modified particle. The final product was characterized. We are currently improving and studying synthesis conditions and aplications.

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  • IPEN-DOC 29591

    RUSSO, DANIELA C.; AMARAL, KLEICY C. ; CALDAS, LHAIS A.; VIEIRA, DANIEL P. ; SARTORELLI, PATRICIA; RIBEIRO FILHO, WALDEMAR A.. Cytototic activity and chemical profile of methanolic extract obtained from Avelós stem (Euphorbia tirucalli L.) Euphorbiaceae. In: SILVA, FERNANDO de C. da (Org.) REUNIAO ANUAL DA SBQ, 45., 31 de maio - 3 de junho, 2022, Maceió, AL. Resumo... São Carlos, SP: Aptor Software, 2022. p. 712-712.

    Abstract: Avelós (Euphorbia tirucalli Linnaeus), a plant selected for this study, has been popularly used in the fight against tumors, arousing the interest of researchers in this area so that it can be used safely in the auxiliary treatment of different types of cancer.1 It belongs to the family Euphorbiaceae and to the genus Euphorbia, it is also the object of studies related to the treatment of a range of infectious and inflammatory diseases. Herbaceous much used by popular and traditional medicine, presents, a latex rich in molecules that confirm its high toxicity. The objective of this research was to verify the chemical profile of the methanolic extract obtained from the stem (modified leaves) of the plant in question and to determine the cytotoxicity of the crude extract by cytotoxic assay against the lineages of adenocarcinoma (MCF-7) and neoplastic cells of human melanoma (SK-MEL-37).2 For this, the plant was collected, and after drying and milling the material was extracted with methanol. Subsequently, the present compounds were separated by the thin-layer chromatography technique and the classes of substances found in the extract were identified by the technique of Nuclear Magnetic Resonance of Hydrogen and Carbon-13 (NMR).3 The combination of cyclohexane with Acetone and Hexane (5:3:2) provided a suitable polarity for the elution of the extract, which was revealed with ultraviolet detection and different reagents: sulfuric acid solutions; aluminum chloride; ferric chloride; 10% potassium hydroxide in ethanol; green bromocresol indicator solution; potassium permanganate, Dragendorff Reagent, vanillin and iodine vapors. The phytochemical study of the methanolic extract of Euphorbia tirucalli allowed to identify the presence of phenolic compounds, flavonoids and terpenes, a result confirmed by NMR spectra. The cytotoxic potential assays, although they are in low concentration thus altering the result, show that the methanolic extract of Euphorbia tirucalli shows activity against the tested cell lines. The observed activity may be related, according to information available in the literature, with the classes identified in the samples studied.

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  • IPEN-DOC 29590

    RAMOS, LUIZ D.; MANTOVANI, MARIANA C. ; SARTORI, ADRIANO; DUTRA, FERNANDO; STEVANI, CASSIUS V.; BECHARA, ETELVINO J.H. Aerobic co-oxidation of hemoglobin and aminoacetone. In: SILVA, FERNANDO de C. da (Org.) REUNIAO ANUAL DA SBQ, 45., 31 de maio - 3 de junho, 2022, Maceió, AL. Resumo... São Carlos, SP: Aptor Software, 2022. p. 164-164.

    Abstract: Aminoacetone (1-aminopropan-2-one), a putative minor biological source of methylglyoxal, reacts like other 􀄮-aminoketones such as 6-aminolevulinic acid (first heme precursor) yielding electrophilic 􀄮-oxoaldehydes, ammonium ion and reactive oxygen species by metal- and hemeprotein catalyzed aerobic oxidation 1,2. A wealth of reports implicates methylglyoxal in protein crosslinking and DNA addition, leading to age-related disorders, including diabetes 3,4. Importantly, methylglyoxal-treated hemoglobin adds four water-exposed arginine residues, which may compromise its physiological role and potentially serve as biomarkers for diabetes 5. In this work, we investigate the co-oxidation of aminoacetone and oxyhemoglobin in normally aerated phosphate buffer, leading to structural changes in hemoglobin, which might reportedly be attributed to the addition of aminoacetone-generated methylglyoxal to the protein. Hydroxyl radical-promoted chemical damage to hemoglobin may also occur in parallel, which is suggested by EPR-spin trapping studies with 5,5-dimethyl-1-pyrroline-N-oxide and ethanol. Concomitantly, oxyhemoglobin is oxidized to methemoglobin, as indicated by characteristic CD spectral changes in the absorption Soret and visible regions. Overall, these findings may contribute to elucidate the molecular mechanisms underlying human diseases associated with hemoglobin dysfunctions (e.g., diabetes) and with aminoacetone in metabolic alterations related to excess of glycine and threonine (e.g., threoninemia, cri-du-chat syndrome).

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  • IPEN-DOC 29589

    PAPAI, RODRIGO; ALMEIDA, GILMAR A. ; SILVEIRA, JOAO R.F.; SILVA, ANDRE L.N.; SANTOS, CELIA A.L.; NAGASIMA, THIAGO P.; JABES, EDUARDO G.; LANDGRAF, FERNANDO J.; LUZ, MACIEL S.. Proposal of an analytical method for Nd, Pr, Fe and B determination in super-magnet alloys by ICP OES. In: SILVA, FERNANDO de C. da (Org.) REUNIAO ANUAL DA SBQ, 45., 31 de maio - 3 de junho, 2022, Maceió, AL. Resumo... São Carlos, SP: Aptor Software, 2022. p. 132-132.

    Abstract: Present in motors, electric turbines and data storage devices (hard disk), magnets are indispensable in the manufacture of computers, televisions, cell phones, smart watches and several modern electronic devices. The chemical composition of the magnet directly influences its magnetic performance and consequently impacts the performance of the products with which it is associated. In this context, the knowledge of the majority chemical composition of these materials contributes to an efficient quality control in the act of production and helps the producers of the high-technology industry to select the magnets in order to maintain a uniformity of these materials. Although there are several types of magnets, those that use rare earth elements generally have strong magnetic activity, and are often called super-magnets. Among the rare earth elements, the mixture of neodymium and praseodymium (didymium) is widely used in metal alloys together with the elements iron and boron for its performance as a supermagnet. The (Nd,Pr)FeB alloy production consists, in summary, to obtain metallic didymium by electrolytic reduction of didymium oxide (mixture of neodymium and praseodymium oxides) followed by iron and boron elements incorporation. The chemical composition control is important to avoid undesirable phases, such alpha-iron, and to control the microstructure formation during the alloy manufacturing step. The chemical composition range must be optimized such that minimizes the use of rare earth elements (Nd and Pr). In this context, this work evaluated the best instrumental conditions for the determination of alloy elements by ICP OES. Interference studies were carried out and the developed method was validated through interlaboratory tests and addition and recovery tests.

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  • IPEN-DOC 29588

    JUNQUEIRA, FERNANDO de C. ; LIMA, JOSE R. de . Linha de feixe adicional para Ciclone 18. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEENG, Abril, 2022. (IPEN-CEN-PSE-CR-006-00-INFT-001-00). Restrito.

    Título do projeto: Prestação de Serviços Tecnológicos

    Palavras-Chave: cyclotrons; beams; accelerators; irradiation devices

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  • IPEN-DOC 29587

    JUNQUEIRA, FERNANDO de C. ; PRADO, ADELK de C. ; LIMA, ANA C. de S. ; ALVES JUNIOR, IREMAR ; DELLAMANO, JOSE C. ; LIMA, JOSE R. de ; RAELE, MARCUS P. . Projeto de protótipos de ferramentas para amostragem dos Geradores de Vapor e da Tampa do Vaso do Reator. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEENG, Novembro, 2022. (IPEN-CEN-P&D-ETN-218-01-INFT-009-00). Restrito.

    Título do projeto: Composição Isotópica dos Rejeitos Radioativos da CNAAA

    Abstract: A obtenção de amostras dos Geradores de Vapor e da Tampa do Vaso do Reator, removidos da unidade 1, e que se encontram depositados no DIGV da CNAAA, se faz necessária para a caracterização desses rejeitos. A Informação Técnica IPEN-CEN-P&D-ETN-218-01-INFT-007-00 apresenta algumas opções de procedimento de amostragem para cada uma destas estruturas. O presente documento tem por objetivo apresentar, em detalhes, a concepção dos projetos do protótipo das ferramentas que possibilitem a realização dos procedimentos de amostragem propostos na referida Informação Técnica. O presente relatório técnico foi elaborado em atendimento ao item 8.2.4 do Plano de trabalho anexo ao Acordo “Determinação da Composição Isotópica dos Rejeitos Radioativos da CNAAA (Fase B)”, do Acordo de Parceria Tecnológica firmado entre a Eletrobrás Termonuclear S.A., a CNEN - Comissão Nacional de Energia Nuclear e a FUNDEP – Fundação de Desenvolvimento da Pesquisa.

    Palavras-Chave: isotope ratio; radioactive wastes; steam generators; reactor vessels; waste storage

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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 .

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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.