IPEN

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  • IPEN-DOC 30179

    QUEIROZ, FERNANDA M.; RIBEIRO, GLEICY de L.X.; CASTRO, RENATO S. de; SANTOS, ROGERIO G. dos; VIEIRA, ALEXANDRE ; TERADA, MAYSA; BUGARIN, ALINE de F.S.; ROSSI, WAGNER de ; COSTA, ISOLDA . Study of the effect of nanosecond laser texturing on the corrosion behavior of Ti6Al4V and Ti6Al4V parts produced by powder bed fusion. Materials Performance and Characterization, v. 12, n. 3, p. 341-350, 2023. DOI: 10.1520/MPC20220109

    Abstract: Combining metallic additive manufacturing with laser texturing could be an alternative in obtaining parts with functional hydrophilic surfaces, which improves osteointegration. Careful study of the corrosion behavior of the surfaces obtained is necessary, because the evolution of this phenomenon can influence the osteointegration of the implant, causing the release of metal ions in the body and even the rejection of the component. This study compared the corrosion behavior of laser texturing Ti6Al4V components with components manufactured using laser power bed fusion of the same alloy followed by laser texturing. Their microstructure, roughness, wettability, and electrochemical behavior were analyzed, and different morphologies and microtopographies were observed comparing both samples. The electrochemical tests obtained indicate that Ti6Al4V showed higher corrosion resistance than L-PBF Ti6Al4V after laser texturing. The results suggest that laser texturing can encourage cell proliferation and osseointegration on the surface of Ti6Al4V biomedical implants.

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  • IPEN-DOC 30180

    SANTOS, JHONATHA R. dos ; BUENO, PATRICIA; JAKUTIS, JONAS; VICTOR, ALESSANDRO R.; BARRETA, LUIZ F.N.; SBAMPATO, MARIA E.; NERI, JOSE W.; SILVEIRA, CARLOS A.B.; RODRIGUES, NICOLAU A.S.; DESTRO, MARCELO G.. Dysprosium optogalvanic spectroscopy in a hollow cathode lamp. Journal of the Optical Society of America B, v. 40, n. 5, p. 1141-1147, 2023. DOI: 10.1364/JOSAB.482663

    Abstract: This work presents data obtained from optogalvanic spectroscopy (OGS) of dysprosium (Dy) using a commercial hollow cathode lamp. Combining laser beams from two tunable dye lasers, it was possible to identify 13 electronic transitions from excited states of the atom not observed or registered in published papers and the NIST database; these lines were observed between 555–575 nm and 585–615 nm. The study of 13 two-step transitions found in this work complement the available data for the Dy which may support other research or any work using this atom.

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  • IPEN-DOC 30178

    SILVA, BRUNO L. da; CARMINATI, SAULO A. ; SOUZA, MATHEUS B.C.; SOARES, LEONARDO C.; LONGO, CLAUDIA; FERNANDEZ, PABLO S.; NOGUEIRA, ANA F.. Photoelectrochemical conversion of glycerol aqueous solution to value-added chemicals using Bi2Fe4O9 as a photoanode. Sustainable Energy and Fuels, v. 7, n. 23, p. 5546-5556, 2023. DOI: 10.1039/d3se01045g

    Abstract: A low-cost, stable and non-toxic Bi2Fe4O9 (BFO) photoanode was used for the first time to promote glycerol aqueous solution photoelectrochemical conversion to hydrogen and value-added chemicals. Photoelectrochemical measurements were performed under AM1.5G irradiation using a three-electrode cell. The best performance was achieved in alkaline medium, where four distinct glycerol oxidation products were detected (glycerate, formate, glycolate and lactate). In neutral medium, no oxidation products were detected. In acidic medium, we observed an improved selectivity, with only glyceraldehyde and dihydroxyacetone as oxidation products. Our results show that the electron–hole recombination, which restricts the efficiency of glycerol conversion, is one of the main shortcomings of BFO. However, its high open circuit potential (OCP) value and several other desirable properties for a good photoelectrocatalyst make it a material worth further research.

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  • IPEN-DOC 30177

    MOLDONADO, EDISON P.; SAMAD, RICARDO E. ; ZUFFI, ARMANDO V.F. ; SANTOS, JHONATHA R. dos ; VIEIRA JUNIOR, NILSON D. . Impact of He+N2 concentration on self-modulated laser wakefield acceleration driven by pulses of a few TW. Journal of the Optical Society of America B, v. 40, n. 4, p. C141-C147, 2023. DOI: 10.1364/JOSAB.482305

    Abstract: Laser wakefield electron acceleration with ionization injection has rarely been studied in the low-power, selfmodulated case. We performed simulations of such regimes using a mixture of He and N2 gases and driven by laser pulses with peak powers around 1 TW. Analyses show the generation of electron bunches with an average energy of up to 70 MeV, an energy spread as low as 18%, and an emittance as good as a fraction of a mm mrad. The obtained electron beam parameters lead to several trade-offs as a function of N2 concentration, allowing for many different designs.

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  • IPEN-DOC 30197

    IGAMI, MERY P.Z. . Repositórios digitais institucionais: a experiência do IPEN/SP. In: MIRANDA, ANGELICA C.D. (Org.); OLIVEIRA, ADRIANA A. (Org.); QUEIROZ, CLAUDETE F. de (Org.); ARAUJO, LUCIANA D. de (Org.). Repositórios: visão e experiência. Rio de Janeiro, RJ: Fiocruz/Icict, 2023. p. 200-212, v. 1,

    Abstract: Descreve-se a experiência do IPEN, objetivando compartilhar conhecimento e contribuir para o avanço do papel que os Repositórios digitais institucionais podem alcançar. O Instituto de Pesquisas Energéticas e Nucleares - IPEN - é um instituto público federal localizado em São Paulo, cuja missão é produzir conhecimento e tecnologia relacionados com as aplicações das técnicas nucleares e das ciências relacionadas, dedicando-se também à formação de recursos humanos, mediante um programa de Pós-Graduação. O relato diz respeito ao processo de migração da base de dados referencial de produção científica institucional, construída na década de oitenta, para o atual Repositório Digital (RD). A citada base de dados referencial foi organizada segundo padrões internacionais, reunindo e atribuindo um tratamento diferenciado à produção científica da instituição, desde a sua criação. Descreve-se essa organização e os atributos que facilitaram o processo de migração e que se tornaram fatores decisivos para o sucesso da atividade. Para funcionamento do atual RD, foram desenvolvidas funções e acrescentados metadados, além dos tradicionais, os quais se constituem em filtros, a fim de favorecer o controle, o monitoramento, a extração de relatórios e principalmente a interoperabilidade com o Sistema Gerencial Institucional, o SIGEPI. O RD fornece dados em tempo real e em fluxo contínuo, apresenta estatísticas de produtividade para a elaboração de indicadores científicos e informações gerenciais para subsidiar os gestores do IPEN. O RD foi construído dentro dos pressupostos do movimento de Acesso Aberto e, por meio de ações de valor agregado atribuído, tornou-se um instrumento de gestão do capital intelectual institucional. Descreve-se também o planejamento para futuras atividades a serem desenvolvidas com o RD.

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  • IPEN-DOC 30176

    MACHADO, MARINA ; TABUTI, F. ; PIAZZOLLA, F. ; MORAES, T. ; ABE, R.; GUIMARAES, R.M.; MIURA, Y.; FUKUYAMA, Y.; FONSECA, F.C. . Steam reforming catalytic layer on anode-supported and metal-supported solid oxide fuel cells for direct ethanol operation. ECS Transactions, v. 111, n. 6, p. 301-311, 2023. DOI: 10.1149/11106.0301ecst

    Abstract: A catalyst based on lanthanum chromite with exsolved metallic ruthenium nanoparticles (LaCrO3-Ru) was applied as a catalytic layer for internal ethanol steam reforming of anode-supported and metal-supported solid oxide fuel cells. The metal support exhibits limited catalytic properties for the ethanol steam reforming reaction. Thus, the LaCrO3-Ru catalysts were optimized for operating temperatures in the 600-700 °C range to promote stable ethanol reforming. The catalytic layer had no significant impact on the electrochemical properties of the fuel cell, and samples with and without the catalytic layer exhibited similar performance in hydrogen. Initial durability tests with LaCrO3-Ru layer have shown that the catalytic layer plays a crucial role in the stability of the metal-supported fuel cell under ethanol.

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  • IPEN-DOC 30196

    SILVA, ANA C.K. de S. ; ZAMBONI, CIBELE B. ; SILVA, DALTON G.N. da . X-ray investigation of graphic art / Investigação de arte gráfica por raios X. In: SEVEN INTERNATIONAL MULTIDISCIPLINARY CONGRESS, 3rd, June 1-2, 2023, Online. Proceedings... São José dos Pinhais, PR: Home Publishing Brazil, 2023. DOI: 10.56238/sevenIIImulti2023-195

    Abstract: X-rays produced by electron ionization provide an analytical tool that can assist investigations in the field of Artistic and Cultural Heritage. In this study, the technique of Energy Dispersive X-ray Fluorescence (EDXF) was employed to investigate collections of postcards from the 1960s produced in Brazil, London and Uruguay. The collections belong to private collections and were made available for analysis at the Radiation Spectroscopy and Spectrometry Laboratory of the Institute for Nuclear and Energy Research (IPEN). This technique is non-destructive and allows the identification of chemical elements present in the different chemical formulations used in the printing industries of each country in the process of preparing postcards. This information allows tracing their origin and identifying copies/fakes, which enables their cataloging and registration for exhibition, as well as providing subsidies for conservators and restorers regarding the preservation and storage of these artistic materials.

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  • IPEN-DOC 30195

    SILVA, RUBENS C. da; MORAIS, PAULO J.D. de; CARVALHO, ANDRE; ROSSI, WAGNER de ; MOTTA, CLAUDIO C.. Thermophoretic efficiency in the MCVD process: a CFD modeling. In: INTERNATIONAL CONFERENCE ON OPTICAL MEMS AND NANOPHOTONICS; SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, July 31 - August 3, 2023, Campinas, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2023. DOI: 10.1109/OMN/SBFOTONIOPC58971.2023.10230917

    Abstract: The thermophoretic efficiency in the modified chemical vapour deposition (MCVD) process has been numerically determined under specified conditions of temperature and velocity field in the silica deposition tube. A CFD code was used to solve a steady-state numerical model of the MCVD process. The cumulative efficiency of SiO2 and GeO2 deposition was calculated along the tube length, yielding to a maximum value of 42% and 37 % respectivelly.

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  • IPEN-DOC 30194

    ZUFFI, ARMANDO V.F. ; SANTOS, JHONATHA R. dos ; SAMAD, RICARDO E. . Ionization model to estimate the density and temperature of fs-laser-induced plasmas in air. In: INTERNATIONAL CONFERENCE ON OPTICAL MEMS AND NANOPHOTONICS; SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, July 31 - August 3, 2023, Campinas, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2023. DOI: 10.1109/OMN/SBFOTONIOPC58971.2023.10230914

    Abstract: We present a simple ionization model to assess the density of plasmas created in air by ionization induced by the electric field of ultrashort laser pulses. It calculates the average ionization induced by the laser taking into account the known threshold intensities for each ionic state, the beam spatial profile and the atmospheric composition, estimating the plasma density. The model density predictions are compared to experimental results obtained by a time-resolved Mach-Zehnder-like interferometer, and are also used as entry parameters to evaluate the plasma temperature by the Saha equation.

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  • IPEN-DOC 30193

    WETTER, NIKLAUS U. ; VIEIRA, RENATO J.R. ; SILVA, DANILO M. da ; JORGE, KELLY C. ; JIMENEZ-VILLAR, ERNESTO ; GIEHL, JULIA M. ; MIRANDA, ADRIANA R. de ; DIPOLD, JESSICA . Random lasers: review of research activities at IPEN. In: INTERNATIONAL CONFERENCE ON OPTICAL MEMS AND NANOPHOTONICS; SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, July 31 - August 3, 2023, Campinas, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2023. DOI: 10.1109/OMN/SBFotonIOPC58971.2023.10230975

    Abstract: Random lasers offer advantages such as low-cost fabrication and robustness in harsh environments and have applications in sensing, imaging, communications, and security. Our current research focuses on advanced materials, active control techniques, integration with other photonic structures, and exploration of Anderson localization and polydisperse effects. Coherent feedback in cavity-enhanced random lasers is discussed as means to achieve specific emission characteristics, and emission at 1300 nm is shown for the first time.

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  • IPEN-DOC 30192

    FAROOQ, SAJID ; GERMANO, GLEICE ; STANCARI, KLEBER A. ; RAFFAELI, ROCIO; CROCE, MARIA V.; CROCE, ADELA E.; ZEZELL, DENISE M. . A 3D discriminant analysis for hyperspectral FTIR images. In: INTERNATIONAL CONFERENCE ON OPTICAL MEMS AND NANOPHOTONICS; SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, July 31 - August 3, 2023, Campinas, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2023. DOI: 10.1109/OMN/SBFOTONIOPC58971.2023.10230933

    Abstract: Here, we apply a 3D discriminant analysis approach to analyze FTIR hyperspectral images of normal vs malignant Melanoma (MM) samples for skin cancer diagnosis. For this porpose we used 2 samples, for Normal (49k) and for MM(90k). Our results evidence the outstanding performance with accuracy up to 81% for big data (> 100k).

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  • IPEN-DOC 30191

    ROMANO, FERNANDO C. ; WETTER, NIKLAUS U. . Transverse electromagnetic modes simulation and experimental measurement technique for a single stripe laser diode. In: INTERNATIONAL CONFERENCE ON OPTICAL MEMS AND NANOPHOTONICS; SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, July 31 - August 3, 2023, Campinas, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2023. DOI: 10.1109/OMN/SBFOTONIOPC58971.2023.10230954

    Abstract: A single stripe multimode laser diode software model has been developed. In addition, a method for measuring the transverse electromagnetic modes (TEM) in the RF spectrum through a frequency beating process was also developed. For supporting the TEM readings, a spectrum analyzer was applied and converted the temporal signals to the frequency domain using the fast Fourier transform (FFT) method.

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  • IPEN-DOC 30190

    PRADO, FELIPE M. ; SOUZA, PEDRO H.M. de; SILVA, SIDNEY L. da; WETTER, NIKLAUS U. . Photoelastic dispersion coefficient by holographic reconstruction with neural networks and the Fresnel method. In: INTERNATIONAL CONFERENCE ON OPTICAL MEMS AND NANOPHOTONICS; SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, July 31 - August 3, 2023, Campinas, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2023. DOI: 10.1109/OMN/SBFOTONIOPC58971.2023.10230956

    Abstract: Here we report the characterization of the photoelastic dispersion coefficient using digital holography with two distinct reconstruction methods: one based on the Fresnel method and the other utilizing convolutional neural networks (CNN). The CNN was trained with reconstruction from the Fresnel method and was able to provide reconstructions with an average Mean Squared Error of 0.006.

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  • IPEN-DOC 30189

    PRADO, FELIPE M. ; FRANCO, TOMAS J.; WETTER, NIKLAUS U. . Highly-efficient, dual-wavelength Nd:YLF laser emitting at 1314 nm and 1047 nm. In: INTERNATIONAL CONFERENCE ON OPTICAL MEMS AND NANOPHOTONICS; SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, July 31 - August 3, 2023, Campinas, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2023. DOI: 10.1109/OMN/SBFOTONIOPC58971.2023.10230922

    Abstract: We report a record optical-to-optical efficiency of 43% and a slope efficiency of 48% for a Nd: YLF laser emitting at 1314 nm. The crystal was side-pumped by a VBG-equipped diode emitting at 797 mn, with a peak power of 1545 W. We also report simultaneous dual-wavelength emission, at 1313 nm and 1047 nm.

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  • IPEN-DOC 30175

    MALDONADO, EDISON P.; SAMAD, RICARDO E. ; ZUFFI, ARMANDO V.F. ; VIEIRA JUNIOR, NILSON D. . Simulation of self-modulated laser wakefield acceleration using few TW in downramp injection and ionization injection regimes. Applied Optics, v. 62, n. 12, p. 3202-3207, 2023. DOI: 10.1364/AO.477401

    Abstract: Simulations of transitional self-modulated laser wakefield acceleration driven by laser pulses of a few terawatts are discussed, comparing a downramp-based injection regime with an ionization injection regime. We demonstrate that a configuration using an N2 gas target and a laser pulse of ∼75mJ with ∼2TW peak power is a good alternative as a high repetition rate system that produces electrons of many tens of MeV, pC charge, and emittance of the order of 1 mm mrad.

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  • IPEN-DOC 30188

    PERES, DANIELLA L. ; FAROOQ, SAJID ; RAFFAELI, ROCIO; CROCE, MARIA V.; CROCE, ADELA E.; ZEZELL, DENISE M. . Identification of basal cell carcinoma skin cancer using FTIR and Machine learning. In: INTERNATIONAL CONFERENCE ON OPTICAL MEMS AND NANOPHOTONICS; SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, July 31 - August 3, 2023, Campinas, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2023. DOI: 10.1109/OMN/SBFOTONIOPC58971.2023.10230945

    Abstract: Here we applied ATR-FTIR spectroscopy combined with computational modeling based on 3D-discriminant analysis (3D-PCA-QDA). Our results present an exceptional performance of 3D-discriminant algorithms to diagnose BCC skin cancer, indicating the accuracy up to 99%.

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  • IPEN-DOC 30187

    BRANDAO, VITORIA M.C. ; SAMAD, RICARDO E. . Development of an Imaging System for an Electron Spectrometer for laser-accelerated electrons. In: INTERNATIONAL CONFERENCE ON OPTICAL MEMS AND NANOPHOTONICS; SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, July 31 - August 3, 2023, Campinas, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2023. DOI: 10.1109/OMN/SBFotonIOPC58971.2023.10230979

    Abstract: We present the results of an electron spectrometer with an imaging system to determine the energy spectrum of laser accelerated electrons. The spectrometer is composed by a region with a constant magnetic field that deflects relativistic electrons according to their kinetic energy, and a luminescent screen into which the electrons impinge. The imaging system optimizes the collection of the screen luminescence, which is inside a vacuum chamber, and magnifies it, through a window, into a CCD in atmosphere that records the light pattern, from which the energy spectrum is recovered.

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  • IPEN-DOC 30186

    FAROOQ, SAJID ; PERES, DANIELLA L. ; CAIXETA, DOUGLAS C.; LIMA, CASSIO; SILVA, ROBINSON S. da; ZEZELL, DENISE M. . Monitoring changes in urine from diabetic rats using ATR-FTIR and Machine Learning. In: INTERNATIONAL CONFERENCE ON OPTICAL MEMS AND NANOPHOTONICS; SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, July 31 - August 3, 2023, Campinas, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2023. DOI: 10.1109/OMN/SBFOTONIOPC58971.2023.10230957

    Abstract: Here, we aim to better characterize diabetes mellitus (DM) by analyzing 149 urine spectral samples, comprising of diabetes versus healthy control groups employing ATR-FTIR spectroscopy, combined with a 3D discriminant analysis machine learning approach. Our results depict that the model is highly precise with accuracy close to 100%.

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  • IPEN-DOC 30174

    ZUFFI, ARMANDO V.F. ; SANTOS, JHONATHA R. dos ; MALDONADO, EDISON P.; VIEIRA JUNIOR, NILSON D. ; SAMAD, RICARDO E. . Femtosecond laser-plasma dynamics study by a time-resolved Mach–Zehnder-like interferometer. Applied Optics, v. 62, n. 8, p. C128-C134, 2023. DOI: 10.1364/AO.477395

    Abstract: Side-view density profiles of a laser-induced plasma were measured by a home-built, time-resolved, Mach–Zehnder-like interferometer. Due to the pump-probe femtosecond resolution of the measurements, the plasma dynamics was observed, along with the pump pulse propagation. The effects of impact ionization and recombination were evidenced during the plasma evolution up to hundreds of picoseconds. This measurement system will integrate our laboratory infrastructure as a key tool for diagnosing gas targets and laser-target interaction in laser wakefield acceleration experiments.

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  • IPEN-DOC 30185

    DIPOLD, JESSICA ; BORDON, CAMILA D.S.; MAGALHAES, EVELLYN S.; KASSAB, LUCIANA R.P.; JIMENEZ-VILLAR, ERNESTO; WETTER, NIKLAUS U. . Random laser emission in Nd3+ doped tellurite glass. In: INTERNATIONAL CONFERENCE ON OPTICAL MEMS AND NANOPHOTONICS; SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, July 31 - August 3, 2023, Campinas, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2023. DOI: 10.1109/OMN/SBFOTONIOPC58971.2023.10230929

    Abstract: Random lasers are easier and cheaper to manufacture than regular ones, being made of several materials such as polymers, powders or dyes. Glass random lasers have been rarely studied due to their inhomogeneous broadened emission and low damage threshold. Here, we study Nd 3 +doped Te0 2 -ZnO-Al 2 0 3 glasses with different concentrations of rare-earth doping (4 wt.%, 8 wt.% and 16 wt.%). Emission intensity per pump fluence and fluorescence decay time measurements showed the potential of these glasses for random laser applications in the near-infrared region.

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  • IPEN-DOC 30184

    CATARINA, MARCUS V. ; BERECZKI, ALLAN ; WETTER, NIKLAUS U. . Sub-nanosecond microchip oscillator for a MOPA system tailored for tattoo removal. In: INTERNATIONAL CONFERENCE ON OPTICAL MEMS AND NANOPHOTONICS; SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, July 31 - August 3, 2023, Campinas, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2023. DOI: 10.1109/OMN/SBFOTONIOPC58971.2023.10230921

    Abstract: In this work we study a microchip laser designed to function as an oscillator in a Master-Oscillator Power-Amplifier (MOPA) system targeted for laser tattoo removal. Different configurations of the Nd: YAG resonator were used by changing the output coupler mirror reflectivities and the initial transmission of the Q-switch. The quasi-CW resonator provided 55.4 W of output with 51.31% and 78.2% optical and slope efficiencies, respectively. For Q-switched operation, the best configuration resulted in a peak output power of 3.6 MW with 588 ps pulse width.

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  • IPEN-DOC 30183

    BERECZKI, ALLAN ; MENEZES, FELIPE C. de ; WETTER, NIKLAUS U. . Compact, high power CW ring laser resonator. In: INTERNATIONAL CONFERENCE ON OPTICAL MEMS AND NANOPHOTONICS; SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, July 31 - August 3, 2023, Campinas, SP. Proceedings... Piscataway, NJ, USA: IEEE, 2023. DOI: 10.1109/OMN/SBFotonIOPC58971.2023.10230968

    Abstract: We demonstrated the dynamically stable operation of aNd: YAG ring laser with 51.8 W of linearly polarized, continuous output power. The laser was based on laser modules side-pumped by diode bars. The resonator, aimed at single-frequency operation, is a design improvement from a previous work with the resonator length 4.3 times smaller than the previous design, thus resulting in a larger free spectral range, favoring for operation at single-frequency.

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  • IPEN-DOC 30173

    MOYA, MURILO T.M.; ARAUJO, LEANDRO G. de ; LOPES, FERNANDO S.; TEIXEIRA, ANTONIO C.S.C.. TiO2 P25 and Kronos vlp 7000 materials activated by simulated solar light for atrazine degradation. International Journal of Chemical Reactor Engineering, v. 21, n. 10, p. 1211-1223, 2023. DOI: 10.1515/ijcre-2022-0186

    Abstract: Photocatalysis-based technologies have been proposed for the treatment of wastewater containing atrazine (ATZ), a persistent and recalcitrant pollutant. This study aims to evaluate and compare the efficiency of TiO2 P25 and TiO2 modified with carbon (C–TiO2 Kronos vlp 7000) in the photocatalytic degradation of ATZ in aqueous systems. The experiments were performed in a tubular photochemical reactor equipped with a compound parabolic collector (CPC) irradiated by simulated solar light. The materials were characterized by X-ray diffraction, infrared spectroscopy, BET specific surface area, and diffuse reflectance spectroscopy. For TiO2 P25, ATZ removals varied in the range 86–100 % after 120 min of irradiation, although the total organic carbon (TOC) analyses indicated that no significant ATZ mineralization occurred (<20 %). C–TiO2 Kronos vlp 7000, on the other hand, was not able to completely remove ATZ after 120 min of irradiation. In this case, pesticide removals were 37–45 % over 120 min, while C–TiO2 performed better with regard to ATZ mineralization, with 38 % TOC removal. Given the low mineralization of atrazine, the intermediate compounds formed were identified for each photocatalytic material.

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  • IPEN-DOC 30172

    OLIVEIRA, ELOANA P.R. de ; VICENTE, JOSE G.; OLIVEIRA, RENE R. de ; COUTO, ANTONIO A. . Fatigue behavior effect of shot peening associated to plasma nitriding surface treatment in F138 stainless steel. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 418-418.

    Abstract: Analysis of shot peening associated to plasma nitriding surface layers on austenitic stainless steel are conduced to verify the influence of the surface treatment in fatigue behavior. Shot peening can be used to increase fatigue resistance, due to the surface residual stress induced. Additionally, shot peening can be used as a previous plasma nitriding treatment to improve nitrogen atoms diffusion, increasing the layer hardness, thickness and fatigue resistance [1]. Thus, the aim of the present work is to study the effect of previous shot peening surface treatment in plasma nitrided F138 stainless steel fatigue properties. Specimens treated with plasma nitriding and shot peening associated to plasma nitriding were analyzed in high cycle fatigue tests. Previous shot peening treatment to plasma nitriding promoted a failure in lower strength values than reference specimens, and its similar to plasma nitride specimens. The result can be associated to roughness increase due to shot peening and plasma nitriding treatments, which can influence fatigue behavior as other surficial morphological characteristics of the formed layer [2]. Fracture surface were analyzed by scanning electron microscopy (SEM) and ductile fracture surface was observed in all conditions. In higher load conditions cracks and microcraks were formed on the sides of the specimen.

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  • IPEN-DOC 30171

    GUARNIERI, GUILHERME de P.; NERY, JOSE G.; COSENTINO, IVANA C. . Converting waste materials into biomaterials: enriched calcium zeolites synthed from chicken eggshells for hemostatic applications. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 399-399.

    Abstract: Although there is a plethora of 245 different zeolites with different frameworks with unique and unusual topologies of channels and cavities with large applications in the field of industrial catalysis [1], few of them have found systematic biomedical applications, especially for the purpose of hemorrhage control. Hemostasis is a complex biochemical process in which the assembly of substrates, enzymes, protein cofactors and calcium ions on a phospholipid surface accelerates the rate of coagulation. Several inorganic solid matrices have been employed as topic hemostatic agents, and among them zeolites [2]. However, the synthesis of enriched calcium zeolites for the purpose of hemorrhage control and using as raw materials chicken eggshell biomass is an unexplored field of research. We report the data of the synthesis of four calcium zeolites using CaCO3 derivated from chicken eggshell. Thromboelastographic results using the pristine calcium enriched zeolites show that they were able to promote a faster clot formation and a higher maximum clot strength than those of the commercial topical hemostatic agent QuikClot.

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  • IPEN-DOC 30170

    SARTORI, MARIANA do N. ; CASTRO, DIONE P. de ; SILVA, LEONARDO G. de A. e . Reuse of textile waste with nano reinforcement for the development of materials incorporated with nanocomposites. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 1933-1933.

    Abstract: The use of plastics in Brazil and the world has shown a growing demand due to their qualities, ease of obtaining, and low cost, and, consequently, produces an increase of these plastics in solid urban waste. The destination of these materials, especially in Brazil, is summarized in sending to landfills, incineration and, mechanical and chemical recycling. This study evaluates the possibility of using polyamide textile waste with elastane discarded by the textile industry, as reinforcement for the development of a polymer-clay composite, on a nanometric scale, and develop a recycling route for these materials. In that, the nanocomposite technology adds value to this material. This work used polyamides from textile waste of the industry. These materials were first processed in a compacting machine. Afterward the composites with 1, 2, and 3% in mass of Verde Clara clay/polyamide were prepared in a double screw extruder. The composites were characterized by techniques of X-ray diffraction (XRD), tensile, flexural, impact tests and thermogravimetric analysis (TGA). Results obtained were compared with the properties of the standard samples. As a conclusion of this study, it can be stated that the polyamide textile scraps with elastane can be reused forming nanocomposites with Verde Clara clay. Verde Clara clay in the proportion of 1% already confers gains in the properties of these nanocomposites.

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  • IPEN-DOC 30169

    SILVA, CRYSTIAN W.C. da ; OTUBO, LARISSA ; SOUZA, KATIUSSE S. de ; CARBONARI, ARTUR W. ; CORREA, BRUNO S. ; FREITAS, RAFAEL S. de; PASCA, GABRIEL A.; COSTA, CLEIDILANE S.. Comparative local analysis of Ni/Ni3C nanoparticles synthed with oleylamine/oleic acid and oleylamine/palm kernel oil ligand pairs: structural and magnetic properties. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 1805-1805.

    Abstract: In recent decades, Ni/Ni3C nanoparticles have been a topic of interest, especially for their catalytic and magnetic properties, promising as electrocatalysis, for example [1]. These systems are usually obtained by chemical methods, in the presence of ligands responsible for controlling their structure and morphology [2]. In this work, we carried out a comparative study of the hyperfine interactions occurring in Ni/Ni3C nanoparticles, synthed by thermal decomposition in the presence of oleylamine/oleic acid and oleylamine/palm kernel oil ligand pairs, at 513 K, for 3 hours. The local analysis was performed using perturbed correlation spectroscopy (PAC) in the temperature range from 30K to 300K, using the 111Cd probe, implanted in the samples by diffusion, during the synthesis. The parameters of the hyperfine interactions were compared to the results obtained by XRD, TEM and magnetization, indicating the obtainment of Ni/Ni3c nanoparticles of the core-shell type, showing a higher Ni3C content, greater distribution and lower saturation magnetization for nanoparticles synthed with palm kernel oil compared to those obtained with oleic acid. In addition, the hyperfine parameters showed the existence of regions with a quadrupole frequency of 24 MHz and a magnetic hyperfine field of 1T in both samples, which may be indicative of carbon-deficient Ni3C regions, predicted in the literature [3].

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  • IPEN-DOC 30168

    QUEIROZ, FERNANDA M.; RIBEIRO, GLEICY de L.X.; CASTRO, RENATO S. de; SANTOS, ROGERIO G. dos; BUGARIN, ALINE de F.S. ; TERADA, MAYSA. Influence of the additive manufacturing parameters on the Ti6Al4V microstructure. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 1374-1374.

    Abstract: The 3D printing on an industrial scale describe the one more advanced techniques. In the manufacturing process technology the model is created by successively layering material from a digital 3D model. The 3D manufacturing process allows obtaining complex geometry, weight reduction, and customized components. A careful microstructure characterization of the produced components is necessary, since the parameters influence in surface roughness, microhardness and corrosion resistance. Samples of Ti6Al4V built with the same laser speed, hatch distance and layer thickness but different laser power were analyzed. The variation in laser power influenced the roughness and corrosion resistance of the samples.

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  • IPEN-DOC 30167

    BUGARIN, ALINE de F.S. ; RIBEIRO, GLEICY de L.X.; CASTRO, RENATO S. de; QUEIROZ, FERNANDA M.; SANTOS, ROGERIO G. dos; TERADA, MAYSA; COSTA, ISOLDA . Influence of texturing parameters on surface modification of UNS S32101 duplex steel. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 1373-1373.

    Abstract: The application of laser texturing aims to modify the surface without changing its chemical composition. These alterations can be evaluated through mechanical, physical or chemical tests. Texturing can be applied to improve efficiency in industrial processes, such as the flowability of materials, by applying laser texturing to the internal surfaces of components. This work aims to evaluate the influence of texturing parameters in the flow process of industrial batchers. UNS S32101 lean duplex stainless steel (LDSS) samples were used for the tests. For laser texturing of the surfaces, laser of Yb was used, with a wavelength of 1064 nm (infrared), using the scanning speed of 140 mm/s and pulse duration of 150 ns. Two sets of textured samples were produced: with a frequency of 50 kHz and 2 kHz. In both frequencys, the power(%) was set at 100, 60 and 20. The effect of texturing was analyzed through microstructural characterization with tests of contact angle, roughness and scanning electron microscopy.

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  • IPEN-DOC 30166

    BUGARIN, ALINE de F.S. ; VIVEIROS, BARBARA V.G. de ; TERADA, MAYSA; GUILHERME, LUIS H.; NEVES, MAURICIO D.M. das ; COSTA, ISOLDA . Syringe cell method to study the corrosion resistance of the UNS S32101 lean duplex stainless steel welded by the gas tungsten arc welding double fusion (GTAW-DF). In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 1178-1178.

    Abstract: This work aims to investigate the corrosion performance of the UNS S32101 lean duplex stainless steel (LDSS) welded by the gas tungsten arc welding double fusion (GTAW-DF). In the study, six welded samples were manufactured with different welding parameters. A Syringe cell was used to characterize the electrochemical behavior of the different welded zones by potentiodynamic polarization tests in NaCl 3,5 % (w.t.) and in a solution of citric acid with addiction of NaCl to simulate the food industry. The results showed that the welding parameters tested significantly affected the corrosion resistance of the LDSS UNS S32101. Besides, a correlation was stablished between microstructure and electrochemical behavior of fusion line (FL), heat affected zone (HAZ) and fusion zone (FZ).

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  • IPEN-DOC 30165

    BARROS, REGIS de M.C. de ; NEVES, MAURICIO . Study of residual stresses and fracture toughness in welded and repaired joints using A516 Gr70 steel. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 1168-1168.

    Abstract: The properties of welded joints subjected to cyclic loading is an important subject in several áreas[1]. In this scenario, aiming to study this subject, welded joints made of ASTM A 516 GR 70 steel plates, with a thickness of 30.5 mm, welded by the MAG – Metal Active Gas process (20% CO2) with the use of a K-bevel were analyzed. to allow full penetration due to the high thickness [2]. The joints were manufactured with seven welding passes on each side of the chamfer. After welding, one set was subjected to a repair pass, for remelting the surface of the bead using the TIG (Tungsten Inert Gas) process, while another set was subjected to two repair passes. This study aimed to analyze aspects of welded and repaired joints: dimensions (height and width) of the bead, behavior of the residual stress profile measured by X-ray diffraction, Vickers microhardness profile and fatigue crack nucleation with based on ASTM E466 and E606 standards. The results indicated that the greater number of repair passes decreased the compressive residual stress values in the transverse and longitudinal directions, from -350 MPa to 50 MPa. There was greater uniformity in hardness Vickers values (value between 200 and 210 HV) with the use of cord repairs. It was observed that the fracture toughness presented values of 1500 J/mm (without repair) and 900 J/mm (one pass and two repair passes), lower than that found in the material without welding (3500 J/mm). Therefore, as the repair passes were performed, the residual stresses in the weld bead tended to positive values, the hardness tended to stabilize with values of 200 HV due to the increase in the number of repair passes and the fracture toughness decreased in the welded material when compared to the values of the non-welded material. There was no significant difference in fracture toughness between repair passes.

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  • IPEN-DOC 30164

    SILVA FILHO, JORGE C.; SILVA, SUELANNY C. da; TAKIISHI, HIDETOSHI ; JANASI, SUZILENE R. ; MARTINEZ, L.G. ; REY, JOSE F.Q.; ESCOTE, MARCIA T.. Influence of reduced graphene oxide on the fabrication to neodymium-iron-boron magnets by mechanical milling. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 1131-1131.

    Abstract: The aim of this work was to prepare sintered Nd-Fe-B permanent magnets, following the traditional powder metallurgy route, using reduced graphene oxide (rGO) in the mechanical milling process. Also, it was to study the effect of rGO addition on the magnetic properties of the as-prepared materials. rGO acts as a lubricant and effective milling medium, preventing agglomeration, welding of the particles, and oxidation of the material. The structure and morphology of the composite powders were characterized by X-ray diffraction, Raman spectroscopy, and transmission electron microscopy. The magnetic properties of sintered magnets were characterized using a permeameter. The highest values of remanence (Br) and intrinsic coercivity (iHc) values were obtained for the sintered magnet using 0.02 wt% rGO addition, Br = 1.1 T, and iHc = 764.0 kAm-1.

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  • IPEN-DOC 30163

    CONCI, MAYCOLN D.; OLIVEIRA, RENE R. ; CENTENO, DANY M.A.; GOLDENSTEIN, HELIO; FARINA, PAULA F. da S.. Evolution of residual stress on AISI D2 tool steel short time tempering. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 1117-1117.

    Abstract: Some parameters are used in an attempt to estimate a relationship between time and tempering heat treatment temperature of steels, among which the Hollomon-Jaffe parameter stands out [1]. This work aimed to study the evolution of residual stresses in short-time tempering treatment of AISI D2 tool steel, compared to conventional heat treatment of tempering [2]. The samples were treated in dilatometry for a better control of the thermal processing variables. Microstructural images were generated using optical and scanning electron microscopy, including mapping using EDS. Vickers microhardness measurements were performed. And the measurements of variations in residual stresses in each of the treatment stages and at the end of the treatment cycles were performed by analyzing the X-ray diffraction data using the Sen2Ψ technique [3]. The cycles composed of tempering in short times carried out at 500 ºC or 600 ºC, for 10 seconds or 1 minute, exhibited residual stress states similar to the conventional cycle, with a tendency towards neutrality of the residual stress state and high hardness values. The final residual stresses acquired by the AISI D2 tool steel in the thermal cycles studied, more specifically in the tempering, can be attributed to the precipitation of tempering carbides, which when carried out up to 600 ºC, occurs coherently, or at least partially coherently, to the matrix, producing the neutrality of residual stresses, but when tempering is carried out at 700 ºC, it leads to incoherent precipitation of carbides and matrix recrystallization, leading to an increase in compressive residual stresses and a reduction in the hardness of the material, regardless of the heat treatment time of tempering.

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  • IPEN-DOC 30162

    TURCARELLI, TIAGO ; CAMARGO, FABIO de; NEVES, MAURICIO M. das . Effect of EBW process welding parameters on AISI 304L stainless steel bead geometry. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 1096-1096.

    Abstract: One important field in the welding researches is the study of the relationship between the welding bead geometry and welding machine parameters. In electron beam welding (EBW) process, the fine controlled parameters enable a detail understand of the weld profile. EBW provides a concentrated beam of energy which can result in a high ratio of weld depth to bead width, which can be called a keyhole. EBW is widely study because of its importance in nuclear and aerospace application, mainly as a result of keyhole bead geometry. The relationship between the welding bead geometry, width root and depth with welding machine parameters is presented in this work by setting beam current and beam deflection frequency. All experiments were carried out on samples of AISI 304L alloy with a thickness (t) = 10 mm, accelerating voltage U = 60 KV, beam current range I = 34 – 43 mA, welding speed v = 480 mm/min, vacuum p < 10-4 mbar, beam deflection width d = 1.2 mm and beam deflection frequency f = 400 / 600 Hz. The weld joint geometry has changed by varying of beam current and beam deflection frequency. The weld penetration was increased by increment of beam current and deflection frequency. Set the frequency at f = 600 Hz and changing the beam current from 34 mA to 39 mA, it was observed that penetration rise from 7.38 mm to 8.46 mm, respectively. On the other hand, when was modified deflection frequency from 400 Hz to 600 Hz, the average welding penetration surged 6.3%. Moreover, with deflection frequency kept in f = 400 Hz, a beam current increment from I = 37 mA to I = 43 mA led to grow the welding penetration from 7.56 to 8.63, respectively. The results of weld width root showed no variation due to an increase of beam current, however applying a change of electron beam deflection frequency from 600 Hz to 400 Hz was verified a slight increase in it. In conclusion, the welding bead geometry is directly affected by varying of current beam and deflection frequency parameters.

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  • IPEN-DOC 30161

    SILVA, ALEXIA O.; NUNES, MATHEUS C. dos S.; YOSHIMURA, ELISABETH M.; RODRIGUES JUNIOR, ORLANDO ; TRINDADE, NEILO M.. Thermoluminescence, fluorescence and electron paramagnetic resonance of natural alexandrite. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 1016-1016.

    Abstract: Recent studies have proposed the investigation of alexandrite mineral (BeAl2O4:Cr3+) as a potential luminescent dosimeter. Despite this, in-depth studies of defects and luminescent centers in alexandrite were not investigated. It is proposed to characterize the thermoluminescence (TL) emission spectra, fluorescence (FL) and electron paramagnetic resonance (EPR) of alexandrite. TL dosimeters, when stimulated by thermal energy, emit light proportional to the dose of ionizing radiation previously absorbed. The emitted wavelength can be measured through thermoluminescence emission spectra. On the other hand, EPR and FL provides additional information about mineral structure, enabling the study of the effects of ionizing radiation on the sample. For TL, the samples were irradiated with Xrays and measured by Lumi22 homemade system. EPR measurements were carried out using a Bruker EMXplus spectrometer operating in the X-band at room temperature, 2 mW microwave power, 100 kHz modulation frequency and 0.25 mT modulation amplitude. The FL spectra were measured using the Duetta spectrofluorometer, with a 75 W xenon arc lamp included. The data was collected by scanning excitation wavelengths in 360-480 nm and recording emission in the wavelength range of 670-740 nm. Preliminary results indicate that the TL emission spectra presented two peaks, at ~80°C and ~175°C, with emission centered between 600 nm – 700 nm, related to Fe3+ and Cr3+, also detected by EPR. The FL spectra showed two signals: an emission centered at 680 nm (Cr3+ in inversion center), and at 700 nm (Cr3+ in mirror symmetry). The results of all techniques used in this work suggest that emissions are correlated to Cr3+ and Fe3+ ions.

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  • IPEN-DOC 30160

    SILVA, BARBARA P.G. ; OTUBO, LARISSA . The influence of PVP molecular weight in the synthesis of silver nanowires using a salt-assisted polyol method. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 877-877.

    Abstract: In the last decades, the demand for new materials to be used in electronic devices has increased. Among the materials that can be used in transparent conductive films (TCFs), are the silver nanowires (AgNWs). This class of material, when supported in glass or PET, e.g., has good conductivity, thermal and mechanical properties and also high transparency. In this work, the AgNWs were synthesized using the polyol method assisted by a salt and the influence of molecular weight of the capping agent polyvinylpyrrolidone (PVP) in the morphology and structure of Ag crystals was investigated. Different molecular weight of PVP (40 K, 120 K, 360 K and 1300 K MW) was used in the synthesis. The surface morphology of the products was observed by scanning electron microscopy and atomic force microscopy. The phase composition and structure were analyzed by X-ray diffraction (XRD) and the XRD patterns diffraction peaks correspond with the face-centered-cubic (fcc) crystalline phase of silver. Transmission electron microscopy was used to analyze the crystal structure, and UV-visible spectroscopy was used to follow the formation of Ag structures. The results indicate that PVP and its chain length have an important role in the formation of silver nanocrystals due to the adsorption and steric effects [1] and as high is the molecular weight of PVP, longer and thinner are the AgNWs as observed by other authors [2]. Different morphologies were obtained when changing the size of PVP chain. For smaller MW of PVP, particles and short wires were formed. Increasing the MW, nanorods and pyramidal particles were formed, and finally, forming nanowires when using the highest MW PVP of the experiments.Improving the aspect ratio of silver nanowires is important to construct TCFs, since the conductivity and transparency properties are improved when they are thinner and longer.

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  • IPEN-DOC 30159

    BENTO, RODRIGO T. ; ABE, IGOR Y.; CORREA, OLANDIR V. ; PILLIS, MARINA F. . Raman spectroscopy applied on the structural characterization of TiO2/expanded graphite films. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 707-707.

    Abstract: Photocatalytic heterojunctions obtained from the use of titanium dioxide (TiO2) and carbon based materials are a promising way for the efficient water treatment [1]. The structural properties of the composite photocatalysts are an important characteristic that can influence their photocatalytic behavior [2]. Here, TiO2/expanded graphite (TiO2-EG) films were synthetized by sol-gel and deposited on borosilicate glass substrates by airbrush spray coating method at room temperature. Then, the hybrid films were heat treated at 350, 450 and 550 °C. Raman spectroscopy technique was applied to evaluate the effect of carbon amount and temperature on the structural properties of the films. The films heat treated at 350 °C exhibited a characteristic profile of amorphous material. Raman spectra of composite films heat treated at 450 and 550 °C showed well-defined peaks that can be attributed to anatase-TiO2phase. No peaks related to the rutile or other phases were observed. The investigation revealed that the G and 2D bands present a slight shift, as well as asymmetry, as the carbon content and heat treatment temperature increase – behavior that may be associated with the formation of the semiconductor-C heterojunction. Peaks deconvolution process demonstrated the presence of a second signal not found in the pure films. This effect may indicate a reduction of sp2 domains after the formation of semiconductor-C heterojunction, mainly due to the removal of oxygenated groups during heat treatment, and consequent Ti-C / Ti-O-C bonds formation [3]. The results suggested that the carbon amount and the temperature of heat treatment have great influence on the TiO2 -EG structural properties, which may contribute to the improvement of the photocatalytic activity of the composite films under visible light.

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  • IPEN-DOC 30158

    ROSERO, WILMMER A.A. ; BARBEZAN, ANGELICA B. ; RIGO, MARIA E.Z. ; RODRIGUES, PRISCILA S. ; TEODORO, LARA E.H. ; TALACIMON, CRISTHIAN F. ; ZEITUNI, CARLOS A. ; ROSTELATO, MARIA E.C.M. . Development of radioactive nanoparticles functionalized with gum arabic to be used in nanobrachytherapy. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 553-553.

    Abstract: The development of new materials emerges as an alternative to the treatment of cancer, from the combination of nanotechnology and brachytherapy a new area of research was born, Nanobrachytherapy, which through the properties of nanometric materials can achieve better results in the fight against cancer. The objective of this work is classified as radiotherapy, which consists of the use of ionizing radiation to destroy or inhibit the growth of abnormal cells that form a tumor. [1] The ability to integrate NPsAu into biological systems is due to the nanometric dimensions of NPsAu probes which facilitate their incorporation into biological systems, as well as their bioconjugation and non-cytotoxic potential. [2] Taking into account the previous objective, gold was selected as the base element for obtaining nanometric systems, which due to its chemical richness and especially due to the intrinsic properties of one of its radioisotopes, which would allow us in theory to meet the stated objective. . Initially, it was based on the knowledge of the literature, and non-radioactive nanometric systems were obtained, and after a series of stability, characterization and application tests, the radioactive nanometric systems were obtained. Working with radioactive systems posed a great challenge, and up to now it presents us with situations to solve, but we have managed to create a methodology for obtaining, characterizing and applying radioactive gold nanoparticles, and also obtaining positive results from their application.

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  • IPEN-DOC 30157

    TEODORO, LARA E.H. ; TALACIMON, CRISTHIAN F. ; RIGO, MARIA E.Z. ; RODRIGUES, PRISCILA S. ; NOGUEIRA, THUANY C. ; ROSERO, WILMMER A.A. ; VIEIRA, JOSE M. ; ZEITUNI, CARLOS A. ; ROSTELATO, MARIA E.C.M. . Possible molds for a new brachytherapy source for spinal and intracranial cancer. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 461-461.

    Abstract: Central Nervous System (CNS) cancer is the 18th most incident cancer in the world, according to the World Health Organization (WHO), and in 2020, in Brazil, it represented 2.5% of all new cancer deaths [1]. Brachytherapy is a type of radiotherapy that positions the radioactive source close to (or in contact with) the tumor. Thus, the targeted region receives most of the dose, protecting the healthy tissues adjacent to the tumor. A promising radioactive source for use in brachytherapy for the treatment of CNS cancer is phosphorus-32 in a polymeric substrate. This source has been prominent as a minimally invasive treatment for craniopharyngiomas and in the treatment of metastatic bone diseases in general [2]. To produce such a source, it is necessary to search for possible molds that can conform the polymeric material into the desired format. Several tests were carried out to determine the best mold for the radioactive source manufacture. Different materials were tested to observe if the mold material would react with the source's components, silicone rubber mixed with orthophosphoric acid. In order to be considered a possible mold, the mixture should cure; if the cure did not concretize, the mold would be descarted. It was concluded that polystyrene (PS) obtained the best result, due to the ease of unmold after the resin curing process.

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  • IPEN-DOC 30150

    CARVALHO, JOAO V.M.S. ; SILVA, ROGERIO M.V.; CALDAS, LINDA V.E. . Validation of a radiotherapy sector with an END-TO-END test in an anthropomorphic phantom for radiosurgery from a 3D printer. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 76.

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  • IPEN-DOC 30156

    GARCIA, JOAO I.M.M.; GOMES, ANDERSON M.; ZAMBUZZI, WILLIAN F.; ICHIKAWA, RODRIGO U. ; SAEKI, MARGARIDA J.. Influence of temperature on obtaining apatites by sol- gel method. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 434-434.

    Abstract: Calcium phosphate-based ceramics (apatites) are synthetic materials that have a chemical composition similar to bone tissue, which makes them interesting to use as biomaterials [1]. In this work, the apatite precursor sols at concentrations of 0.7 mol/L and 1.4 mol/L are prepared by dissolving calcium nitrate and phosphorus pentoxide in ethanol. The sols are kept at rest for 24 hours for hydrolysis (gelatinization) under room temperature and humidity. After hydrolysis, the resulting gels are dried at 80°C to remove the organic solvent and then calcined under different temperatures (from 500°C to 1200°C, with increments of 100°C) for 8h [2]. The X-ray diffraction analysis of the samples by the Rietveld method indicates that the samples are composed of monoclinic and hexagonal hydroxyapatite (HAp), the former being predominant, and calcium β-triphosphate (TCP)[3] . For the material started from the sol with a concentration of 0.7 mol/L, the hydroxyapatite fraction increases from 28.8% to 66.5% when the calcination temperature increases from 500°C to 800°C. Above this temperature, the fraction of this phase decreases. With a concentration of 1.4 mol/L, the hydroxyapatite fraction decreases from 88.2% to 19.5% progressively with increasing temperature from 500°C to 1200°C. The micrographs revealed the formation of particulate but porous materials that agglomerate without sintering up to a temperature of 900°C, from where the formation of sintered and dense agglomerates is observed. The results of the EDX analysis showed a Ca/P molar ratio of around 1.5 for all materials. The cytotoxicity assay, using pre-osteoblast cells (MC3T3-E1, Subclone 4) by non-direct contact of 24h, showed that cell viability and adhesion did not differ from those of the control. A decrease in viability and adhesion was observed for samples prepared at a concentration of 0.7 mol/L and calcined at temperatures above 900°C.

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  • IPEN-DOC 30155

    LOURENCO, LARISSA R.; BORGES, ROGER; CARASTAN, DANILO J.; MATHOR, MONICA B. ; MARCHI, JULIANA. Chitosan hydrogel containing bioactive glass aiming at 3D printing for tissue engineering. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 349-349.

    Abstract: 3D printing is a rising processing technique in tissue engineering due to high reproducibility and the possibility of complex or even patient-specific models. Chitosan is a promising biomaterial for both 3D printing and tissue engineering, because of its biocompatibility, rheological properties, biodegradability, and cost-effectiveness. Bioactive glasses can help the regeneration of different biological tissues and act as reinforcement for chitosan matrix. In this work, chitosan hydrogels were produced with different concentrations of 58S bioactive glass (0.5 up to 5%wt). For the rheological characterization, frequency, and recovery experiments were carried out. Printability and shape fidelity were evaluated during the 3D printing process. Indirect cytotoxicity assay using Balb/c 3T3 cells was performed to evaluate the biological properties of the scaffolds. The presence of the glass maintained the viscosity properties and increased the recovery percentage. All materials formed filaments and allowed printing with suitable form maintenance. Biological experiments showed high cell viability for all 3D scaffolds, even though a reduction was observed for higher glass concentrations. The results indicate that the studied materials are printable and potentially recommended for tissue engineering applications.

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  • IPEN-DOC 30154

    QUEIROZ, CARLOS A. da S. . Preparation of lanthanum acetate from a mixed rare earths concentrate. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 1153-1153.

    Abstract: A simple and economical chemical process to obtaining lanthanum acetate of high purity was studied. The raw material in the form of mixed rare earths carbonate 24% La2O3 comes from commercial Brazilian monazite. It is used the technique of strong cationic exchange resin, proper to water treatment to the lanthanum''s fractionation and it is achieved a purity of 99.9% La2O3 and yield greater than or equal 90%, with the elution of rare earths by EDTA solution at pH 4.0. The complex of EDTA-La is transformed in La2O3 , subsequently the lanthanum oxide is dissolved in acetic acid to obtain the cerium acetate. The solid salt then is characterized via chemical analysis, thermal analysis, X ray diffraction, infrared spectroscopy and mass spectrometry to certify the lanthanum acetate purity. The analytical data collected allowed to conclude that the stechiometric formula for the compound is La (CH3COO)3.1.5 H2O.

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  • IPEN-DOC 30153

    LOBO, RAQUEL de M. ; CASTAGNET, MARIANO ; MIRANDA, CARLOS A. de J. ; FALOPPA, ALTAIR A. ; LIMA, JOSE R. de ; MATTAR NETO, MIGUEL ; PEREIRA, LETICIA dos S. ; ANDRADE, ARNALDO H.P. de . Correlations of mechanical properties by SPT (Small Punch Test) and conventional tensile test for Al 6061 – T6. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 1084-1084.

    Abstract: The Small Punch Test (SPT) was development by nuclear industries to analyses mechanical properties of irradiated materials principally by small volume of the samples. This technique intend to evaluate the materials behavior during the time life of nuclear reactors, where yours properties changed by irradiation intensity and exposition time. It is considered an almost ¨non-destructive” method [2] due to small sample volume and its applications are spreading for use in situations where conventional methods do not apply. SPT consists of pressing a sphere, with a diameter equal to 2.5 mm, in a miniaturized sample of circular geometry (diameter d = 8 mm and thickness about 0.5 mm)[1], which has fixed edges, tested in conventional mechanical testing machines with the aid of a device developed for their achievement. In this work, mechanical properties of aluminum (Al 6061-T6) were abstained by two different methods: conventional tensile test and the small punch test (SPT). The SPT results depends on graph interpretations and discussions take place at now. Correlations of results guide us in choosing the most appropriated method for interpreting the force x displacement graph from SPT.

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  • IPEN-DOC 30149

    NOGUEIRA, THUANY ; TALACIMON, CRISTHIAN ; TEODORO, LARA ; RIGO, MARIA ; RODRIGUES, PRISCILA ; ANGELOCCI, LUCAS ; NOVAES, HAMONA ; ZEITUNI, CARLOS ; ROSTELATO, MARIA . Thermoluminescent dosimetry planning through MNCP. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 190.

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  • IPEN-DOC 30152

    PEREIRA, MARIA da C.C. ; MADI FILHO, TUFIC ; BERRETTA, JOSE R. ; ALVES, JOAO P. da S. . Response of CsI:Pb scintillator crystal to neutron radiation. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 1014-1014.

    Abstract: The helium-3 world crisis requires a development of new methods of neutron detection to replace commonly used 3He proportional counters. In the past decades, great effort was made to developed efficient and fast scintillators to detect radiation.[1] These detectors should, then, be carefully characterized both experimentally and by means of advanced simulation code. Ideally, the detector should have the capability to separate neutron and gamma induced events either by amplitude or through pulse shape differences. As neutron sources also generate gamma radiation, which can interfere with the measurement, it is necessary that the detector be able to discriminate the presence of such radiation. Considerable progress has been achieved to develop new inorganic scintillators, in particular increasing the light output and decreasing the decay time by optimized doping. Crystals may be found to suit neutron detection. In this report, we will present the results of the study of lead doped cesium iodide crystals (CsI:Pb) grown in our laboratory, using the vertical Bridgman technique. The concentration of the lead doping element (Pb) was studied in the range 5x10-4M to 10-2M. The crystals grown were subjected to annealing (heat treatment). In this procedure, vacuum of 10-6 mbar and continuous temperature of 350°C, for 24 hours, were employed. In response to neutron radiation, an AmBe source with energy range of 1 MeV to 12 MeV was used. The activity of the AmBe source was 1Ci Am. The fluency was 2.6 x 106 neutrons/second. The operating voltage of the photomultiplier tube was 1300 V; the accumulation time in the counting process was 600 s and 1800 s. The scintillator crystals used were cut with dimensions of 20 mm diameter and 10 mm height. The Monte Carlo method was used to determine the neutron flux arriving in the detector and the calculated values were obtained by means of MCNP code.

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  • IPEN-DOC 30151

    OLIVEIRA, RAPHAEL A.M.P. de; TRINDADE, FABIANE J.; FLORIO, DANIEL Z. de; FONSECA, FABIO C. ; ESPOSITO, VINCENZO; FERLAUTO, ANDRE S.. Effects of La content in ceria-lanthana thin films prepared by pulsed laser deposition. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 810-810.

    Abstract: Solid oxide electrochemical reactors are a promising alternative for challenging chemical reactions, such as oxidative coupling of methane (OCM)[1], which convert methane to C2+products. Cerium oxide is a commonly studied oxide membrane material for its high ionic conductivity in the temperature range ideal for conversion reactions (600-900°C), particularly when doped with rare earth cations like Gd, Sm, or La. Recent studies have shown La2Ce2O7as a promising OCM catalyst[2]. This study investigates the structural properties of LaxCe(1-x)O2(1-x/2)thin films, prepared using pulsed laser deposition, with varying stoichiometry. XRD results indicate textured film growth with preferential [100] orientation of cubic crystalline fluorite for low La content (x≤0.5), while x>0.5 had a random orientation. La doping expanded the fluorite structure, increasing lattice parameters from 5.42 Å for x=0 to 5.69 Å for x=0.7. UV-Raman spectroscopy showed that La content x=10 caused a more pronounced balance between Ce4+and Ce3+than pure ceria samples. Impedance revealed a direct relationship between La content and resistance, indicating lower resistance with lower La content. These findings could lead to using Ce-La oxides thin films as catalysts for OCM in electrochemical reactors based on ceria.

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  • IPEN-DOC 30130

    ANTONIO, PATRICIA L. ; SILVEIRA, IURY S. ; CALDAS, LINDA V.E. . Thermoluminescence and phototransferred thermoluminescence of radiation dosimeters:: analysis of the effect of UV light for transfer of charges from deep traps. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 123.

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  • IPEN-DOC 30129

    DIAS, F.S. ; GIOVANNI, D.N.S. ; POTIENS JUNIOR, A.J. ; RODRIGUES JUNIOR, O. ; POTIENS, M.P.A. ; ZAMBONI, C.B. . Study on the radiation exposure of Portable X-ray Fluorescence. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 107.

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  • IPEN-DOC 30148

    SA, MARCELO C. de ; CALVO, WILSON P. ; SOMESSARI, SAMIR L. . Regulatory requirements and economic feasibility for developing a mobile SPECT/CT unit with radiopharmacy facilities. In: INTERNATIONAL SYMPOSIUM ON TRENDS IN RADIOPHARMACEUTICALS, April 17-21, 2023, Vienna, Austria. Abstract... Vienna, Austria: International Atomic Energy Agency - IAEA, 2023. p. 168-168.

    Abstract: Brazil has been facing great challenges related to the public health care system, not being able to manage the high national demand for diagnostic imaging tests, therefore avoiding the possibility of an early diagnosis for oncological and cardiovascular diseases. An important medical specialty for providing an early and accurate diagnosis is Nuclear Medicine. Early diagnosis is crucial for health professionals to make decisions that enable more effective treatments and improve the chances of cure. Due to the irreversible damages caused to patient’s health resulting of delay in diagnosis, this research project carried out at Nuclear and Energy Research Institute (IPEN/CNEN), together private companies and associated institutions, focus on regulatory requirements and economic feasibility for developing a mobile unit with hybrid Single Photon Emission Computed Tomography/Computed Tomography (SPECT/CT) equipment and radiopharmaceuticals facilities for radiolabeling reagents kits with technetium-99m. A mobile SPECT/CT unit with adequate radiopharmacy facilities will be an excellent innovative solution to support Brazilian public hospitals to address the demand for diagnostic imaging tests. This mobile unit could provide health care in isolated areas or even big cities where there are shortage of health resources and high mortality rate for cancer and heart disease.

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  • IPEN-DOC 30147

    SANTOS, KATIA C. ; BERNARDES, EMERSON S. ; CALVO, WILSON P. . Production and application of 177Lu-PSMA and 225Ac-PSMA in the sustainable innovation model through Balanced Scorecard (BSC). In: INTERNATIONAL SYMPOSIUM ON TRENDS IN RADIOPHARMACEUTICALS, April 17-21, 2023, Vienna, Austria. Abstract... Vienna, Austria: International Atomic Energy Agency - IAEA, 2023. p. 173-173.

    Abstract: 177Lu-PSMA and 225Ac-PSMA appear in the theranostic concept, with astonishing results in prostate cancer patients, who did not respond to conventional therapies. In Europe, these treatments are used successfully. However, in Brazil, 30% of patients do not respond well to new radiopharmaceuticals, requiring broader studies. The "Multicenter program using PSMA radioligands for diagnosis and therapy of patients with prostate cancer", in which this research project is inserted, in partnership among the Nuclear and Energy Research Institute (IPEN-CNEN), a private company and associated institutions, aims to expand the therapeutic alternatives for patients with cancer unresponsive to the treatments available in the public health network in the State of São Paulo. IPEN-CNEN will produce the radiopharmaceuticals that will be distributed to Public Hospitals responsible for the selection, treatment and follow-up of patients with metastatic castrationresistant prostate cancer (mCPRC), and for the genetic and molecular characterization of patients unresponsive to treatment. The present research will study the technical and economic feasibility in the production and application of these radiopharmaceuticals, with clinical studies in patients with mCPRC, applying the Balanced Scorecard (BSC) management tool, measuring its performance by indicators aiming at a strategic and efficient management, with the possibility of theirs marketing.

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  • IPEN-DOC 30146

    ROSTELATO, MARIA E.C.M. ; FEHER, ANSELMO ; ZEITUNI, CARLOS A. ; ROSERO, WILMMER A.A. ; SOUZA, CARLA D. de ; MOURA, JOÃO A. . Nationalization of brachytherapy radioactive sources in Brazil and the importance of IAEA cooperation. In: INTERNATIONAL SYMPOSIUM ON TRENDS IN RADIOPHARMACEUTICALS, April 17-21, 2023, Vienna, Austria. Abstract... Vienna, Austria: International Atomic Energy Agency - IAEA, 2023. p. 23-23.

    Abstract: Brazil has a cancer incidence of about 625,000 cases a year. It is a public health problem, demanding constant efforts to deliver for patients the most efficient treatment modalities, improving their life expectancy and quality. Brachytherapy is a type of Radiotherapy where the radioactive source is placed close to or inside the tumor. The main advantage of the technique is to deliver the maximum dose in the target, saving healthy tissues. In Brazil, Our group had the objective of producing sources nationally, diminishing treatment costs, enabling the treatment to more patients. Some of our projects are developed in collaboration with the International Atomic Energy Agency-IAEA by technical cooperation projects. The IAEA participation is very important to provide technological transfer through scientific visits, expert missions, and contacts with more advanced centers. The financial support is also important, allowing us to buy the necessary equipment to make these cancer treatment sources production feasible in Brazil. Our team has received training through fellowships. We received some experts and organized several workshops to propagate the Brachytherapy technique at national and Latin American level. For producing new sources, five major areas must be considered: 1) source production: nuclear activation and/or radiochemical reaction; 2) welding; 3) quality control: leakage tests; 4) dosimetry and metrology; 5) operational procedures; 6) validation studies. To perform all steps, a multidisciplinary team works together to overcome difficulties. Our major projects are: Iridium-192 pellets: In Brazil there are 150 afterloading machines with pellets that replacement every 4 months (about 450 Iridium-192 sources a year). Our new production line, with the support of IAEA, is in progress, with the hot-cell being installed in a brand-new facility. Iridium-192 wires: In production since 1997, also supported by IAEA. The wire is activated at IPEN’s IEA-R1 reactor for 30 hours with 5x1013 n/cm-2.s-1 neutron flux resulting in 7.1 GBq (192 mCi) maximum activity. Iridium-192 seed: New seed for ophthalmic cancer treatment. The core presented 90% activity homogeneity. We are making the experimental dosimetry and Monte Carlo simulation. Iodine-125 seeds: Largely used in low dose brachytherapy. I-125 binding yield achieved with our new reaction was 90%; Laser welding presented 70% efficiency. Approved in all leakage tests. Our Iodine-125 seeds laboratory production is 90% ready. Other ongoing projects: polymeric Phosphorus-32 source for spinal cancer treatment, Gold-198 nanoparticles for prostate, breast, and liver cancer treatment, Iodine-125 seed as markers for non-palpable cancers, and dosimetry calculations for all new sources. All the projects are advancing, despite national funding difficulties. Withing those, several mSc, Phd, and Post-doc are getting their degrees. We will continue to develop new products hoping to help the Brazilian population fight against cancer. The support of IAEA has proven to be of the utmost importance for these projects not only in direct funding, but in providing knowledge to our team, the possibility to share information with the scientific community, and to form the next generation of scientists.

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  • IPEN-DOC 30128

    SAVI, M.; VILLANI, D. ; ANDRADE, M.A.B.; SOARES, F.A.P.; RODRIGUES JUNIOR, O. ; CAMPOS, L.L. ; POTIENS, M.P.A. . Step-by-step of 3D printing a head-and-neck phantom: proposal of a methodology using fused filament fabrication (FFF) technology. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 43.

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  • IPEN-DOC 30145

    ROSERO, WILMMER A.A. ; BARBEZAN, ANGELICA B. ; ROSTELATO, MARIA E.C.M. ; SOUZA, CARLA D. de ; NOGUEIRA, BEATRIZ R. ; ZEITUNI, CARLOS A. . Synthesis, activation and application testing of gold nanoparticles for nanobrachytherapy. In: INTERNATIONAL SYMPOSIUM ON TRENDS IN RADIOPHARMACEUTICALS, April 17-21, 2023, Vienna, Austria. Abstract... Vienna, Austria: International Atomic Energy Agency - IAEA, 2023. p. 24-24.

    Abstract: For more than 50 years, the Energy and Nuclear Research Institute IPEN, has been offering solutions to Brazil through nuclear technology. Thus, one of the main areas where IPEN has contributed assertively is medicine. Reaching the level of 32 radiopharmaceuticals and radioactive sources intended both for therapy and for the diagnosis of several pathologies, including cancer, which are obtained with the help of the two nuclear reactors and two cyclotrons present in the institution. The Institute has a team for the development, production and distribution of radioactive sources for brachytherapy, such as 192 Ir wires and 125 I seeds. Brachytherapy is a cancer treatment technique where the radioactive source is placed close to or in contact with the lesion. The great advantage of the technique is to save healthy tissues. Currently, we are working on obtaining nanometric materials that can be applied in the emerging nano brachytherapy, because of its properties and characteristics at the nanometric level, gold has been the subject of studies and tests. Elemental Au gold can be activated 198 Au inside a nuclear reactor, and has β- decay and a half-life of 2.7 days, which makes it ideal for short-term irradiations. In addition, gold in the form of nanoparticles has a completely different chemistry, with gold nanoparticles (AuNPs) being easily functionalized by a large part of molecular and polymeric binders, which may present favorable characteristics for the studies, and together with AuNPs they are able to work synergistically to achieve greater efficiencies. Currently, AuNPs have been successfully functionalized with gum arabic (GA), a coating widely used in the cosmetic and food industry, which is low cost and along with nanoparticles has shown biocompatibility with different cell groups and has been shown to be very stable over time. The project includes studies regarding the synthesis of nanoparticles, coating, cytotoxicity of AuNPs in vitro "cold" (non-radioactive) and the development of activation protocols in the nuclear reactor. In the next phase, after activation, in the reactor, "hot" tests will be performed in vitro and in vivo.

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  • IPEN-DOC 30144

    FERREIRA, ARYEL ; FREITAS, LUCAS F. de ; GAMARRA, LIONEL F.; MARQUES, FABIO N. ; LUGAO, ADEMAR . Preclinical validation of freeze-dried kit of albumin nanoparticles synthesized by a radiolytic method. In: INTERNATIONAL SYMPOSIUM ON TRENDS IN RADIOPHARMACEUTICALS, April 17-21, 2023, Vienna, Austria. Abstract... Vienna, Austria: International Atomic Energy Agency - IAEA, 2023. p. 195-195.

    Abstract: Radiopharmaceutical kits containing human serum albumin nanoparticles (HSA-NP), which after radiolabeling with Sodium Pertechnetate solution (99mTc) results in nanocolloids, are already commercialized by international companies. These kits are used to characterize the lymphatic system and, in particular, to detect sentinel lymph nodes in breast cancer and melanoma patients. Albumin has also recently been extensively utilized to form nanoparticles for drug delivery in cancer, i.e., Abraxane®, an FDA-approved nanomedicine consisting in paclitaxel encapsulated by albumin nanoparticles (130 nm), for metastatic breast cancer treatment (2005), lung cancer (2012), and metastatic pancreatic adenocarcinoma (2013). Well-established literature data, and experimental data obtained by our CRP research, demonstrate that albumin nanoparticles synthesized by gamma radiation have the potential to become a similar product to those available on the market. As the particle size distribution is well defined and parameters such as qualitative and quantitative composition are relevant and comparable to commercial ones. The albumin nanoparticles produced by radiation synthesis were lyophilized in a radiopharmaceutical kit containing HSA-NPs, Poloxamer 188, sodium phytate, tin chloride, glucose, and anhydrous disodium hydrogen phosphate. The OECD Guidelines for the Testing of Chemicals were performed to assure the safety of using the albumin nanoparticle freeze dried kits. The development of studies included: Genotoxicity tests (OEDC 471: Bacterial Reverse Mutation Test, OECD 474: Mammalian Erythrocyte Micronucleus Test), Carcinogenicity tests (OECD 453: Combined Chronic Toxicity/Carcinogenicity Studies) and Acute Toxicity (OEDC 420). In addition, biodistribution of 99mTc radiolabeled albumin nanoparticle was performed in healthy mice. The results show that HSA-NP was not able to induce chromosomal breaks and/or chromosomal gain or loss under experimental conditions, indicating no genotoxic effect. Furthermore, it was considered non-mutagenic, as it did not induce mutations by shifting the reading frame or substitution of base pairs in the genome of the strains used (TA97a, TA98, TA100, TA102 and TA1535). The treated rats had weight gain and the blood counts showed no abnormalities, in the same way normal biochemical parameters were found indicating the nontoxicity of the product. Furthermore, the ex-vivo biodistribution study in normal mice showed rapid blood clearance with high hepatobiliary and low renal excretion, which is in agreement with literature studies and commercial products leaflets.

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  • IPEN-DOC 30143

    FERREIRA, ARYEL . Heterodimer peptide based on RGD and NPY analog for breast tumor targeting. In: INTERNATIONAL SYMPOSIUM ON TRENDS IN RADIOPHARMACEUTICALS, April 17-21, 2023, Vienna, Austria. Abstract... Vienna, Austria: International Atomic Energy Agency - IAEA, 2023. p. 189-189.

    Abstract: Heterodimer peptides targeting more than one receptor target can be advantageous as tumors can simultaneously express more than one receptor type. The design of heterodimer peptides can significantly increase the avidity and specificity of the contrast agent due to simultaneous binding to more than one type of receptor or at least one receptor independently, compared to their corresponding monospecific counterparts. A heterodimer molecule consisting of cyclic RGD and NPY analog motifs in a single probe is an attractive approach, as both receptors are overexpressed simultaneously in breast cancer. We hypothesize that a peptide ligand recognizing both αvβ3 integrin and NPY receptors will be advantageous because of its dual-receptor-targeting ability, which could enable the determination of disease location, monitoring of pathological and molecular changes associated with payload delivery, as well as a comprehensive view of the material behavior in vivo that can be utilized to guide therapeutic and diagnostic interventions. The HYNIC-cRGDfk-NPY peptide was radiolabeled with 99mTc using tricine/EDDA as coligand. The cellular-specific binding of [99mTc]HYNIC-cRGDfk-NPY was evaluated on different cell lines as well as with a blocking experiment on MCF-7 and MDA-MB231 (human breast cancer cells). The proof-of-concept of tumor-targeting was performed through ex vivo biodistribution in normal mice, MCF-7 and MDA-MB231 tumor-bearing mice also in SPECT/CT images. By using tricine/EDDA as a coligand, labeling yield was more than 97%. The in vitro cell uptake test showed that this radiolabeled peptide had a good affinity to MDA-MB231 and MCF-7 cells. The in vivo results showed a tumor/muscle ratio of 5.65 ± 0.94 for MCF-7 model, and 7.78 ± 3.20 for MDAMB231 Also, tumor uptake was reduced significantly from 9.30% to 4.41% (MCF-7) and from 4.93 % to 2.3% (MDA-MB231) in blocking study whereas 500-fold molar excess of cold peptide was injected 30 min prior to the injection of related radioconjugated peptide suggesting the potencial of heterobivalent radioligand [99mTc]-HYNIC-cRDGfk-NPY to target breast tumors targeting.

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  • IPEN-DOC 30127

    TEODORO, LARA E.H. ; BURIN, ANA L. ; TALACIMON, CRISTHIAN F. ; MEDEIROS, ILCA M.M.A. ; RIGO, MARIA E.Z. ; TAVARES, PAULO V. dos S. ; RODRIGUES, PRISCILA S. ; NOGUEIRA, THUANY C. ; ROSERO, WILMMER A.A. ; RODRIGUES JUNIOR, ORLANDO ; VIEIRA, JOSE M. ; ZEITUNI, CARLOS A. ; ROSTELATO, MARIA E.C.M. . Using a Monte Carlo simulation to analyze the ideal activity for a phosphorus-32 polymeric brachytherapy source for paraspinal tumors. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 171.

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  • IPEN-DOC 30142

    FEHER, ANSELMO ; BAPTISTA, TATYANA S. ; ZEITUNI, CARLOS A. ; ROSTELATO, MARIA E.C.M. ; MOURA, JOÃO A. . Challenges in iodine-125 sources production for cancer treatment. In: INTERNATIONAL SYMPOSIUM ON TRENDS IN RADIOPHARMACEUTICALS, April 17-21, 2023, Vienna, Austria. Abstract... Vienna, Austria: International Atomic Energy Agency - IAEA, 2023. p. 25-25.

    Abstract: There is a great challenge the implantation on assurance quality system in the brachytherapy sources production. It involves tofulfill the Good Manufacturing Practices (GMPs) requirements, involving the process validation and of all supporting activities such as cleaning and sanitization. The purpose of this work was to execute a process validation in the iodine-125 seeds production on Radiation Technology Center located at IPEN- Brazil. Besides this, the sanitization was to evaluate the effectiveness of different surface cleaning products, determining the best to reduce radiological contamination to acceptable levels during the sources production, according to legislation. The fabrication process was performed three times for evaluation. The parameters evaluated in this study were: the source welding efficiency and the leakage tests results (immersion test). The welding efficiency doesn’t have an established parameter, since is visually evaluated by the operator, and the leakage detection has to be under 5 nCi / 185 Bq, accordingly with the ISO 9978. In the relation of sanitization, it was established a cleaning program for three production lots of iodine 125 seeds using three types of sanitizers: Lot 1 with extran 1/1 (v/v), Lot 2 with hydrogen peroxide 6% and Lot 3 with sodium hydroxide 1M. Each lots contained seven iodine 125 seeds and was immersed in the sanitizer for 1 hour and then two washes with distilled water. An activity detected in each lots does not exceed 0,2 kBq (˭5nCi). The observed values on process validation were: 75% welding efficiency and 32% leakage detection. Although established values for the global efficiency aren’t available in the literature, the results showed high consistency and acceptable percentages, especially when other similar manufacturing processes are used in comparison (average 85-70% found in the literature for other similar metallic structures). According to results of sanitization, the best choice for remove de surface contamination was peroxide hydrogen. Further testing should ensure the sanitizer's choice is based not only on the removal of surface contamination, but also this sanitizer does not leave residues requiring further rinsing with distilled water. Those values will be important data when drafting the validation document and to follow the Good Manufacturing Practices (GMPs).

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  • IPEN-DOC 30126

    ALMEIDA, S.B. ; CUNHA, A.P.V.; TAVARES, P.V.S. ; SAMPAIO, C.C.; MENEGUSSI, G.; CAMPOS, L.L. . Small field dosimetry employing the thermoluminescence technique using a 3D printed phantom. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 170.

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  • IPEN-DOC 30141

    DAL BELO, FELIPE ; BERNARDES, EMERSON ; NASCIMENTO, FERNANDO C. ; CALVO, WILSON A.P. . Application of Data Science and Artificial Intelligence in the productive efficiency of radiopharmaceuticals. In: INTERNATIONAL SYMPOSIUM ON TRENDS IN RADIOPHARMACEUTICALS, April 17-21, 2023, Vienna, Austria. Abstract... Vienna, Austria: International Atomic Energy Agency - IAEA, 2023. p. 220-220.

    Abstract: The present research addresses the application of Data Science and Artificial Intelligence in the production processes of injectable radiopharmaceuticals in the Radiopharmacy Center, at IPENCNEN. Center of greatest relevance and production scale in Latin America and one of the main international ones, which is currently undergoing technological adaptation of its production processes. Given the economic and therapeutic importance of the Nuclear Medicine market in global health systems, valued at USD 5,351.90 million in 2017, it is estimated that it will reach USD 9,981.30 million by 2026, growing at an annual rate. Average of 7.2% over the forecast period. As a main objective, the study proposes to develop and obtain an innovative operating model applying automation, Artificial Intelligence resources and Data Science techniques (analytics), to make the routine of processes and operational indicators safer, predictable, effective and efficient. This Doctoral study will provide the scientific community of medicine and nuclear technology with the benefits and returns of the application of artificial intelligence and data science in critical regulatory, diagnostic and therapeutic activities. And the results will lead to the Radiopharmacy Center, modernization, innovation and a differential in the practices of its core activities. Therefore, it is expected to implement through these technologies the improvement in the critical stages of its production processes, combined with the digital trends of efficiency and good manufacturing practices.

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  • IPEN-DOC 30140

    BALOGH, TATIANA S. ; MARQUES, FABIO N. ; KADLUBOWSKI, SLAWOMIR ; LUGAO, ADEMAR B. . Direct radiolabeling of PVP-nanogel from 99mTcO4: reaction. In: INTERNATIONAL SYMPOSIUM ON TRENDS IN RADIOPHARMACEUTICALS, April 17-21, 2023, Vienna, Austria. Abstract... Vienna, Austria: International Atomic Energy Agency - IAEA, 2023. p. 255-255.

    Abstract: Nanogels are considered promising drug delivery systems for different pathologies, mainly associated with neurological disease, by intranasal administration since drug transport occurs via the olfactory nerve, causing rapid delivery to the brain. The present work aimed to evaluate a protocol for 99mTc labeling of poly(N-vinylpyrrolidone) (PVP) nanogel synthesized by an electron beam for future in vivo biodistribution assays. 10 mM PVP K-90 solution saturated with N2O was irradiated by e-beam using a dose of 7 kGy and a dose rate of 5.35 kGy/s. Nanoparticles characteristic was evaluated by DLS technique to determine the Rh and SLS to determine the Mw and Rg. Rg/Rh and ρcoil were calculated. The sample was morphologically characterized using AFM. The same analyzes were performed with a non-irradiated PVP solution. Radiolabeling was performed by mixing 0.55 mg of SnCl2.2H2O in 50 μL of HCl 0.1 M with (A) 450 μL 0.2 M NaOAc buffer, pH 4.1; (B) 200 μL 0.2 M NaOAc buffer, pH 4.1 and 0.5 M NaHCO3 buffer, pH 7.26; (C) filtered solution B in a 0.22 μm syringe filter. To the solutions (A), (B), and (C) were added 200 μL of nanogel (8.9 mg of PVP K-90), 100 μL of 99mTcO4- (860-980 μCi), and the samples were stirred at 500 rpm for 90 minutes at room temperature. The reaction was assessed by W3MM paper/acetone chromatography at the end of the process. All solutions were filtered through a 0.22 μm filter to remove 99mTcO2, as a previously validated process, and the radioactivity in the filter and the solution was measured. Finally, the solutions were concentred in the Amicon® (10 kD), and the radioactivity of the filtered and retained solution were measured too. The solution remaining on the filter was diluted with 300 μl of purified water and the concentration process was repeated twice. Filter content and the sum of filtered solutions 1 and 2 had the radioactivity measured to check labeling efficiency. Nanogel was obtained with an average for Rh of 12.49 nm, Rg of 6.8 nm, Mw of 1.32 x 106 g/mol, ρcoil of 786.98, and Rg/Rh of 0.620. High relief spherical structures were observed in the AFM images instead of the low roughness film observed in the non-irradiated PVP solution. Chromatographic analysis of the sample prepared only with NaOAc buffer (final pH 3.8) and of the sample with the mixture of buffers without previous filtration (final pH 6.8) indicated, respectively, 99.89 and 99.68% associated with the formation of 99mTc-PVP nanogel or 9mTc-colloid. In contrast, the sample prepared with the mixture of buffers and previously filtered (final pH 6.8) showed 80.10% of nonreduced 99mTcO4. Filtration results at 0.22 μm showed that the 9mTccolloid remains 100% retained in the filter, while free 99mTcO4 and 99mTc-PVP nanogel are filtered. Amicon® filtration confirmed 95.75% and 92% of 99mTc-PVP nanogel formation in the samples with NaOAc buffer and a mixture of buffers without previous filtration, respectively. It was possible to synthesize nanogel by electron beam, obtaining an average Rh of 12.49 nm. The labeling process with 99mTcO4- showed a high radiochemical yield in samples prepared with NaOAc buffer and a mixture of buffers without previous filtration.

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  • IPEN-DOC 30125

    ANTONIO, PATRICIA L. ; SILVEIRA, IURY S. ; CALDAS, LINDA V.E. . OSL and PTOSL of dosimetric materials: observation of the luminescence after exposure to 90Sr+90Y source and LEDs in ultraviolet range. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 124.

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  • IPEN-DOC 30139

    ZAMBONI, CIBELE B. ; GIOVANNI, DALTON N.S. ; KOKA, ANA C. ; STANOJEV, MARCO . Young Scientist Project presents Neutron Life. In: ENCONTRO DE PRIMAVERA DA SOCIEDADE BRASILEIRA DE FÍSICA, 3.; REUNIÃO DE TRABALHO SOBRE FÍSICA NUCLEAR NO BRASIL, 45.; ENCONTRO NACIONAL DE FÍSICA DE PARTÍCULAS E CAMPOS, 42., 26-29 de setembro, 2023, Niterói, RJ. Resumo... São Paulo, SP: Sociedade Brasileira de Física, 2023.

    Abstract: The Young Scientist Project was created in 2019, by the team of the Spectroscopy and Spectrometry of Radiation Laboratory (LEER/IPEN), with the proposal to implement nuclear knowledge in academia and for the general public. The objective is to develop alternative proposals for knowledge, application and dissemination of nuclear physics using social networks. The website www.jovemcientista.com.br design involves four menus: REPORTS where researchers talk about their career and perspectives in the field; NUCLEAR MINUTE: where nuclear physics concepts are covered in one-minute videos; CURIOSITIES: a space where various themes are presented, including several nuclear applications; INTERVIEWS: conducted by students to discuss its work and a COMMUNICATION CHANNEL with the entire team. All activities involve the participation of students from scientific initiation to post-doc and the content produced is available on social networks YouTube (Jovem Cientista), Instagram (@jovemcientista.com.br) associated with a Facebook page Facebook (@jovemcientista.com.br), TikTok (@jovemcientista.com.br) and by LinkedIn and Twitter in the editors’; profile. Now, we are present a new menu NEUTRON LIFE whose content is produced mainly for graduate students. The idea is to present topics related to neutron physics in a relaxed way, through the elaboration of videos and comic strips. Since the implementation of the Young Scientist Project, interaction with students and the public has been positive, helping to demystify and disseminate nuclear physics.

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  • IPEN-DOC 30124

    FRANÇA, MARIA B.A.; ANTONIO, PATRICIA L. ; NASCIMENTO, ERIBERTO O.; CALDAS, LINDA V.E. ; OLIVEIRA, LUCAS N. de. Natural detector irradiated with blue LEDs for measurements in Photodynamic Therapy (PDT) via Spectroscopy (UV-Vis), Design of Experiments (DOE) and Multiple Linear Regression (MLR). In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 75.

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  • IPEN-DOC 30138

    ZAMBONI, CIBELE B. ; SILVA, DALTON G.N. da ; BOGNAR, MARTA L.; SILVA NETO, GALDINO V. da. Multi-analytical X-ray study of the honorary decoration of the Order of Christ. In: ENCONTRO DE PRIMAVERA DA SOCIEDADE BRASILEIRA DE FÍSICA, 3.; REUNIÃO DE TRABALHO SOBRE FÍSICA NUCLEAR NO BRASIL, 45.; ENCONTRO NACIONAL DE FÍSICA DE PARTÍCULAS E CAMPOS, 42., 26-29 de setembro, 2023, Niterói, RJ. Resumo... São Paulo, SP: Sociedade Brasileira de Física, 2023.

    Abstract: The analysis of cultural heritage objects can generate information about techniques of minting of the time, giving information not only on chronology but also regarding preparation methodology, and provenance. In this investigation, three honorable mentions (metal artifacts) of the order of Christ (cross, lady's and gentlemen's medal) were performed using Energy Dispersive X-ray Fluorescence (EDXRF) technique. This analysis were performed with a portable Amptek assemble of Si-drift XR-100SSD (25 mm2 × 500 μm) detector, equipped with a 12.5 μm Be entrance window, pre-amplifier and digital pulse multichannel processor and Ag target. Analytical parameters were 5 μA and 30 kV for 180 s at 2 mm distance to the target. Points distributed in distinct parts were analyzed in each of the metal artifact. The WinQxas software was employed for spectral analyses. These data provide to curators and historians knowledge for cataloging and subsidies for correct storage. In addition, they can be used to identify forgeries (heritage appreciation).

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  • IPEN-DOC 30137

    SILVA, DALTON G.N. da ; ZAMBONI, CIBELE B. ; PECEQUILO, BRIGITTE R.S. ; ESPOSITO, SELENE E.; PIMENTA, DANIEL C.; SIMONS, SIMONE M.. Multielemental characterization of the pollen produced by Scaptotrigona aff postica bee from Brazil using EDXRF technique. In: ENCONTRO DE PRIMAVERA DA SOCIEDADE BRASILEIRA DE FÍSICA, 3.; REUNIÃO DE TRABALHO SOBRE FÍSICA NUCLEAR NO BRASIL, 45.; ENCONTRO NACIONAL DE FÍSICA DE PARTÍCULAS E CAMPOS, 42., 26-29 de setembro, 2023, Niterói, RJ. Resumo... São Paulo, SP: Sociedade Brasileira de Física, 2023.

    Abstract: The objective of this investigation was to perform a multielemental characterization of the pollen produced by Scaptotrigona aff Postiça Bee (popularly known as “tubi”). In recent years, the demand for natural and healthy products has grown significantly and products from Meliponiculture (creation of stingless bees) have started to be consumed on a larger scale in Brazil. Specifically, pollen has gained prominence in the nutritional field for being a protein source and rich in carbohydrates, lipids, mineral trace elements, fibers, hormones and vitamins, but scientific research is still scarce, especially regarding studies of its specific composition. The aim of this investigation was to evaluate the content of inorganic elements (multielemental analysis) in pollen from “tubi” bees. Pollen samples were collected during a one year, in a meliponary of Barra do Corda city, in the state of Maranhão. The EDXRF analyzes were carried out using an X-Ray Fluorescence spectrometer (X-123SDD, Amptek), constituted by a Silicon detector coupled a mini X-ray tube (Ag). These data are the first estimates of mineral trace elements in this natural product and provide benefits to beekeepers regarding their characteristic specifications. In addition contributes with relevant data in the nutritional field.

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  • IPEN-DOC 30123

    TALACIMON, CRISTHIAN ; ILCA, MEDEIROS ; TEODORO, LARA ; RIGO, MARIA ; GESSERAME, MAYSA ; TAVARES, PAULO ; RODRIGUES, PRISCILA ; NOGUEIRA, THUANY ; ROSERO, WILMMER ; RODRIGUES JUNIOR, ORLANDO ; ZEITUNI, CARLOS ; ROSTELATO, MARIA . Investigating a dopant for mitigating the natural degradation of Fricke Xylenol Gel dosimeters. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ICDA, 2023. p. 64.

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  • IPEN-DOC 30136

    SILVA, ANA C.K. de S. ; ZAMBONI, CIBELE B. ; ALMEIDA, MATEUS R. de ; SILVA, DALTON G.N. da . Application of the X-ray fluorescence analysis to determine the elemental composition of Brazilian Olympic coins. In: ENCONTRO DE PRIMAVERA DA SOCIEDADE BRASILEIRA DE FÍSICA, 3.; REUNIÃO DE TRABALHO SOBRE FÍSICA NUCLEAR NO BRASIL, 45.; ENCONTRO NACIONAL DE FÍSICA DE PARTÍCULAS E CAMPOS, 42., 26-29 de setembro, 2023, Niterói, RJ. Resumo... São Paulo, SP: Sociedade Brasileira de Física, 2023.

    Abstract: In this investigation, the elemental composition of Brazilian Olympic coins was investigated using Energy Dispersive X-ray Fluorescence (EDXRF) analytic technique. From the release of Olympic albums (2014, 2015, and 2016) the demand for these coins has increased and some can be worth up to 7000% more than their normal value. The analysis was performed using a compact X-ray spectrometer model X-123 SDD with Ag target. The characteristic X-ray fluorescent intensity of Ka lines were measured with a Si Drift detector (25 mm² x 500 μm) with Be window (12.5 μm). For the spectrometer calibration, certified standard solutions from Z = 14 to Z = 51 were evaluated. The results were compared with coins in current circulation. All the spectral analysis was performed using WinQxas software. The spectral analysis of Olympic coins shows Cr, Mn, Fe and Cu as majorities and peaks of various elements as traces. The 2014 and 2015 Olympic coins groups exhibited similar surface compositions for majorities and trace elements (V, Ni, Mo, Ag, In, Sn, Ce, Nd, Ir and Pb), while the 2016 group coins exhibited Nb presence as a trace element. Some differences were also identified when the comparison was made with current coins. These data provide curators with information for cataloging as well as being used to identify forgeries (heritage appreciation), important for collectors.

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  • IPEN-DOC 30135

    OLIVEIRA, THALES Z. dos S. de ; ZAMBONI, CIBELE B. . Analysis of Ca and Fe in supplements by EDXRF technique. In: ENCONTRO DE PRIMAVERA DA SOCIEDADE BRASILEIRA DE FÍSICA, 3.; REUNIÃO DE TRABALHO SOBRE FÍSICA NUCLEAR NO BRASIL, 45.; ENCONTRO NACIONAL DE FÍSICA DE PARTÍCULAS E CAMPOS, 42., 26-29 de setembro, 2023, Niterói, RJ. Resumo... São Paulo, SP: Sociedade Brasileira de Física, 2023.

    Abstract: Measurements of the elemental composition of supplements is relevant in the nutritionalcontext for the consumer, as well as for the professional for the correct prescription, since thenational legislation still does not oblige the manufacturer to determine the content ofminerals, with the exception of sodium. According to Euromonitor (market research onconsumer products, commercial industries, demographics trends and consumer lifestyles inBrasil) the most consumed minerals were calcium (13%), followed by iron (4%). Anothermarket research carried out at the end of 2020 by “Associação Brasileira da Indústria deAlimentos para Fins Especiais e Congêneres” (Abiad) also emphases that consumption ofdietary supplements increased by 10% in the last five years in Brazil. In this study, the Ca andFe content in food supplements commercially available at São Paulo city were evaluatedusing the Energy Dispersion X-Ray Fluorescence (FRX-ED) technique. The data wereobtained using a compact X- Ray spectrometer (X-123 SDD, Amptek) constituted by a SDDdetector coupled a mini X-ray tube (Ag). Concentration results were compared with thoseprovided by the manufacturer.

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  • IPEN-DOC 30134

    GOES, MARIA P. de O. ; BENEDITO, MARIA G.M. ; CAMPOS, DANIEL de O. ; ZAMBONI, CIBELE B. . Establishment of zinc concentrations in blood of elite runners by NAA. In: ENCONTRO DE PRIMAVERA DA SOCIEDADE BRASILEIRA DE FÍSICA, 3.; REUNIÃO DE TRABALHO SOBRE FÍSICA NUCLEAR NO BRASIL, 45.; ENCONTRO NACIONAL DE FÍSICA DE PARTÍCULAS E CAMPOS, 42., 26-29 de setembro, 2023, Niterói, RJ. Resumo... São Paulo, SP: Sociedade Brasileira de Física, 2023.

    Abstract: The purpose of this study was to use Neutron Activation Analysis (NAA) to investigate Zn levels in blood of elite athletes (long-distance runners), and compared with a reference population. Zinc is a co-factor for numerous enzymes implicated in several physiological processes, DNA reproduction, cellular respiration, endocrine system, and immune response. High aerobic activity and dietary habits may result in the depletion of body zinc stores, which could decrease aerobic performance, increasing the risks of fatigue and immune disorders. In this study, samples were collected from 10 elite athletes (6 men and 4 women), in constant training for the last 6 years, and 58 healthy individuals (30 men and 28 women) of the same age but not involved in physical activities. The samples were irradiated in the IEA-R1 nuclear reactor (3.5-4.0 MW, pool type) at IPEN. The comparison for female groups (control and athletes) exhibited a decrease in Zn concentrations. Furthermore, the blood Zn concentrations in athletes are higher in men than in women. These data can be considered for the preparation of a balanced diet, for evaluating the performance of the athletes during the competitive period as well as, to present a new evaluation of clinical protocol using NAA technique.

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  • IPEN-DOC 30122

    MEDEIROS, ILCA M.A.M. ; SILVA, ANA C.K. de S. ; TALACIMON, CRISTHIAN F. ; MOURA, JOAO A. ; TEODORO, LARA E.H. ; RIGO, MARIA E.Z. ; RODRIGUES, PRISCILA S. ; ROSERO, WILMMER A.A. ; ROSTELATO, MARIA E.C.M. ; ZEITUNI, CARLOS A. . How to select a dosimeter?. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 217.

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  • IPEN-DOC 30121

    TALACIMON, CRISTHIAN ; MEDEIROS, ILCA ; TEODORO, LARA ; RIGO, MARIA ; GESSERAME, MAYSA ; TAVARES, PAULO ; RODRIGUES, PRISCILA ; NOGUEIRA, THUANY ; ROSERO, WILMMER ; RODRIGUES JUNIOR, ORLANDO ; ZEITUNI, CARLOS ; ROSTELATO, MARIA ELISA CHUERY MA . Feasibility study of fricke xylenol gel as a dosimeter for low dose rate brachytherapy sources. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 63.

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  • IPEN-DOC 30120

    GONCALVES, JOSEMARY A.C. ; MANGIAROTTI, ALESSIO; SOMESSARI, ELIZABETH S.R. ; NAPOLITANO, CELIA M. ; BUENO, CARMEN C. . Online electron beam monitoring with a diode-based dosimetry system in routine quality control. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 119.

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  • IPEN-DOC 30119

    SANTOS, S.C. ; RODRIGUES JUNIOR, O. ; CAMPOS, L.L. . EPR characterization of thulium-yttria micro rods. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 118.

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  • IPEN-DOC 30133

    PINTO, MAYARA S. ; ROSERO, WILMMER A.A. ; ROSTELATO, MARIA E.M.C. ; RIBEIRO, MARTHA S. . Photobiomodulation therapy combined with radioactive gold nanoparticles in breast cancer-bearing mice. In: ANNUAL MEETING OF THE BRAZILIAN BIOPHYSICAL SOCIETY, 47th, October 19-22, 2023, Campinas, SP. Abstract... Campinas, SP: Galoá, 2023.

    Abstract: Breast cancers are responsible for the highest number of worldwide deaths among women requiring new therapeutic strategies to promote better life’s quality and survival rates for patients. Nanobrachytherapy (NB) and photobiomodulation therapy (PBM) emerge in this context as less invasive approaches for breast cancer treatment. NB is a technique that might deliver high doses of ionizing radiation in a shorter time and in a localized way in comparison to conventional radiotherapy and PBM could enhance cell sensitivity when applied before NB. In this work, we aim to investigate the impact of PBM combined with NB involving radioactive gold nanoparticles (AuNPs) in the treatment of breast cancer in a murine model. Murine 4T1 cells were cultivated in RPMI medium and after injected into the lower-left mammary fat pad animals’ breast. When the tumor reached approximately 0.1 cm3, AuNPs (~284 microCi) were inoculated in the mouse breast. Thereafter, the tumor was irradiated with a red LED (660 nm, 40 mW, 150 s, 6 J) in a single application. Animals were monitored for 3 weeks until euthanasia. Our results demonstrated an arrestment in tumor growth for NB group in comparison to Control, PBM and PBM + NB groups. These data suggest that a single PBM session was not able to enhance the NB of breast cancer. The following steps will involve applying NB and PBM in two sessions. The first session will take place on the same day as NB application, and the second one after 6 days, corresponding to two half-lives of 198AuNPs.

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  • IPEN-DOC 30132

    SILVA, ABDENEGO R. ; CABRAL, FERNANDA V. ; SILVA, CAMILA R. ; SILVA, DANIELA F.T. ; FREITAS, ANDERSON Z. ; FONTES, ADRIANA; RIBEIRO, MARTHA S. . Photodynamic inactivation against the critical priority pathogen Candida auris. In: ANNUAL MEETING OF THE BRAZILIAN BIOPHYSICAL SOCIETY, 47th, October 19-22, 2023, Campinas, SP. Abstract... Campinas, SP: Galoá, 2023.

    Abstract: Fungal pathogens and their associated infections present a growing challenge to global public health. Among these pathogens, Candida auris has emerged as a highly hazardous hospital-acquired microorganism, included in the critical priority group by the World Health Organization. Methylene Blue (MB) is a widely acknowledged photosensitizer utilized in antifungal photodynamic inactivation (PDI) and holds significant clinical applications. The MB methylation results in the formation of a more lipophilic compound, the 1,9-dimethyl MB (DMMB), which can have an enhanced interaction with cell membranes. Nevertheless, PDI mediated by DMMB to combat fungi remains little explored. In this study, we assessed the impact and underlying mechanisms of PDI using MB (MB-PDI) or DMMB (DMMB-PDI) combined with a red LED against C. auris. PDI was conducted on the CBS 10913 strain of C. auris, utilizing different concentrations of MB (0 – 100 μM) or DMMB (0 – 3 μM) at light doses of 10 or 30 J/cm². To evaluate the PDI efficacy, we measured colony-forming units and monitored reactive oxygen species (ROS) production. Additionally, we assessed lipid peroxidation (LPO) and mitochondrial membrane potential (ΔΨm) to gain insights into the differences between MB and DMMB. Our findings revealed that DMMB-PDI successfully eradicated C. auris yeasts at 3 μM concentration, irrespective of the light dose, whereas MB (100 μM) only exhibited cell eradication at the highest light dose. ROS formation was more pronounced for DMMB than MB at 10 J/cm2. At 30 J/cm2, MB and DMMB produced similar ROS levels. In sublethal conditions, DMMB-PDI induced significantly higher LPO, and ΔΨm levels compared to MB-PDI. Furthermore, DMMB-PDI effectively inhibited biofilm formation and disrupted mature biofilms, with no observed toxicity in fibroblast cells. In conclusion, our study demonstrates the potential of DMMB-PDI as a promising weapon to combat the global priority pathogen C. auris. The enhanced PDI efficacy and biofilm eradication capacity of DMMB make it a valuable candidate for further exploration in the fight against this hazardous pathogen. As the incidence of drug-resistant fungal infections continues to rise, the development of innovative and effective therapeutic strategies like DMMB-PDI is crucial in safeguarding public health worldwide.

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  • IPEN-DOC 30131

    LIMA, GEYSE S. de; SOUZA, SUEDEN O. de; RAPOSO, BRUNO L.; SANTANA, GLEYCIANE S. de; SARMENTO-NETO, JOSE F.; SANTOS, BEATE S.; NEVES, REJANE P.; RIBEIRO, MARTHA S. ; REBOUCAS, JULIO S.; CABRAL FILHO, PAULO E.; FONTES, ADRIANA. Photodynamic inactivation of Candida glabrata boosted by association of silver nanoparticles with cationic ZnTE-2-PyP4+ porphyrin. In: ANNUAL MEETING OF THE BRAZILIAN BIOPHYSICAL SOCIETY, 47th, October 19-22, 2023, Campinas, SP. Abstract... Campinas, SP: Galoá, 2023.

    Abstract: Candida glabrata, a high priority fungal pathogen, presents alarming incidence and resistance potential to available antifungals. In this scenario, photodynamic inactivation (PDI) introduces a promising antifungal approach, especially in resistant cases. PDI occurs when a photosensitizer (PS) is excited by an appropriate light source, leading to production of reactive oxygen species (ROS). Zinc porphyrins (ZnPs) are attractive PSs for their efficient ROS generation and cellular uptake. The plasmonic effect of silver nanoparticles (AgNPs) can be explored to potentiate the action of PSs, such as ZnPs, in PDI. Therefore, this work aimed to study the association of AgNPs with ZnTE-2-PyP4+ (ZnP-ethyl) in PDI against C. glabrata. AgNPs were synthesized and characterized by absorption spectroscopy and electron microscopy. The association AgNP:ZnP-ethyl was evaluated by zeta potential (ζ) analyses as well as absorption and emission spectroscopies. The systems containing AgNP:ZnP-ethyl (at different proportions; v/v) and different ZnP-ethyl concentrations (0.5 – 1.5 µM) were prepared and incubated with a resistant isolate of C. glabrata, followed by illumination with a blue LED. The PDI effect was assessed by quantifying colony forming units. AgNPs presented spherical morphology and extinction maximum at ~410 nm, overlapping with the ZnP-ethyl absorption spectra. Variations in ζ confirmed the association between AgNPs and ZnP-ethyl, corroborated by subtle changes in the ZnP spectroscopic profile. The AgNP:ZnP-ethyl systems promoted complete fungal eradication at 0.6 µM, while at 0.5 µM they promoted yeast reduction of ca. 5.7 log10 (1:4; v/v) and 6.8 log10 (4:1; v/v). Illuminated AgNPs had no antimicrobial effect alone, and individual ZnP-ethyl (1.5 µM) promoted a 2 log10 reduction. These results show the benefit of AgNPs:ZnP-ethyl association to boost PDI efficiency against resistant C. glabrata isolates. This is a promising antifungal approach to treat resistant candidiasis.

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  • IPEN-DOC 30118

    RIGO, MARIA ; ANGELOCCI, LUCAS ; RODRIGUES, PRISCILA ; TALACIMON, CRISTHIAN ; MEDEIROS, ILCA ; TEODORO, LARA ; NOGUEIRA, THUANY ; ROSERO, WILMMER ; ZEITUNI, CARLOS ; ROSTELATO, MARIA . Dosimetric approach of Au-198 nanoparticles with radiochromic film. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 57.

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  • IPEN-DOC 30101

    CAMPOS, IVAN D. . Estudo de compósitos de poli (ácido lático) com celulose extraída da coroa do abacaxi / Study of poly (lactic acid) composites with cellulose extracted from the pineapple crown . 2022. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 71 p. Orientador: Duclerc Fernandes Parra. DOI: 10.11606/D.85.2022.tde-28122023-095246

    Abstract: A incessante busca pela redução de poluentes no mundo, principalmente os oriundos dos plásticos sintéticos, faz com que muitos pesquisadores recorram a pesquisas de materiais alternativos. Neste estudo, foram preparados 5 Compósitos de PLA contendo 0,5%, 1,0%, 1,5%, 5% e 10% de fibra de abacaxi. Foram ensaiadas a partir do PLA puro e PLA com adição de fibras, sem acréscimo de nenhum estabilizante ou qualquer outro material nas amostras com 0,5%, 1,0% e 1,5%, com foco na estratégia de verificação do comportamento do PLA com a fibra considerando como referência o PLA puro e as amostras com 5,0% e 10,0% foram adicionadas de compatibilizante Polybond. As fibras foram trituradas e incorporadas no PLA no estado fundido por meio de um moinho de facas e, em seguida, as formulações foram homogeneizadas em uma extrusora dupla rosca. Os corpos de prova foram obtidos em uma prensa a 180ºC e em seguida cortados com gabarito. A caracterização das amostras foi realizada por meio das técnicas de ensaios mecânicos, Calorimetria Diferencial Exploratória (DSC), Termogravimetria (TGA), Espectroscopia no Infravermelho por Transformada de Fourier (FT-IR) e Microscopia Eletrônica de Varredura (MEV). O comportamento do compósito trouxe uma alteração na dureza a partir da adição de fibras no PLA, em torno de 3,8% na amostra PLA + 0,5% Fibra; 8,9% na amostra PLA + 1,0% Fibra; 6,2% na amostra PLA + 1,5% Fibra;13,5% na amostra PLA + 5% Fibra e 6,5% na amostra PLA + 10% Fibra. Quanto ao impacto, o compósito PLA + fibra apresentou um ganho em sua resistência. A matriz com adição de fibras, apresentou uma melhora na resistência à tração. Quanto ao comportamento térmico, observa-se que os compósitos com fibra não apresentam alterações de estabilidade térmica, permanecendo assim, na mesma faixa de degradação do polímero puro e da fibra.

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  • IPEN-DOC 30117

    MARTINS, ELAINE W. ; POTIENS, MARIA P.A. . Performance evaluation of activity meters using the in-situ calibration methodology with 99mTc. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 56.

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  • IPEN-DOC 30100

    RIBEIRO, ROGÉRIO B. . Datação de sedimentos do terraço arenoso de São Vicente : correlação com a flutuação do mar no passado / Sediment dating of the sandy terrace of São Vicente: correlation with past sea-level fluctuation . 2022. Tese (Doutorado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 149 p. Orientador: Shigueo Watanabe. DOI: 10.11606/T.85.2022.tde-13112023-121735

    Abstract: O estudo das planícies costeiras dispõe de diversos métodos de datação. Entre esses métodos, destacam-se a ressonância paramagnética eletrônica (EPR) e a termoluminescência (TL). No entanto, esses métodos ainda apresentam problemas metodológicos, uma vez que são relativamente recentes e não estão perfeitamente calibrados em comparação com os métodos de radiocarbono (14C). Neste trabalho, foram utilizadas amostras de sedimentos coletadas na área continental do município de São Vicente, no estado de São Paulo. Os grãos foram extraídos do sedimento arenoso por meio de tratamento químico com H2O2 (20%), HF (10%) e HCl (15%). A caracterização dos grãos foi realizada por meio do método de EPR, que permitiu avaliar os centros paramagnéticos presentes no quartzo, como os de ferro [Fe]3+, vanádio [VO]2+, centro E'1 representados por [SiO3]+ e [SiO3]3-, titânio [TiO4]0, alumínio [AlO4]0 e peroxy [SiO5]-. Além disso, foram estimadas as idades por TL utilizando o método de múltiplas alíquotas e dose aditiva (MAAD). Os resultados obtidos pela caracterização indicam que os grãos extraídos do sedimento são compostos principalmente por quartzo (95.5%), seguido pela titanita (4.3%) e outros minerais (0.2%). Os centros paramagnéticos de titânio, ferro, vanádio, E'1 e peroxy foram identificados, no entanto, o centro de alumínio não foi identificado. A comparação das estimativas de idade por TL e (14C) valida a abordagem proposta, demonstrando a concordância do uso do sinal TL para datar grãos compostos predominantemente por quartzo e extraídos de sedimento arenoso não recozido. No entanto, é importante ressaltar que as idades obtidas por TL não coincidem completamente com as idades obtidas por 14C. Essa discrepância pode ser atribuída a diferenças nas características dos materiais datados por ambos os métodos, bem como às complexidades inerentes aos processos de datação.

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  • IPEN-DOC 30116

    GONCALVES, JOSEMARY A.C. ; MANGIAROTTI, ALESSIO; POTIENS, MARIA P.A. ; CALDAS, LINDA V.E. ; BUENO, CARMEN C. . Dosimetric parameters and radiation tolerance of epitaxial diodes for diagnostic radiology and computed tomography X-rays. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ICDA, 2023. p. 49.

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  • IPEN-DOC 30099

    ANTENOR, JOAO P.M. . Avaliação dos parâmetros de produção para otimização microestrutural de pastilhas de dióxido de urânio (UO2) / Evaluation of production parameters for microstructural optimization of uranium dioxide (UO2) pellets . 2023. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 105 p. Orientador: Humberto Gracher Riella. DOI: 10.11606/D.85.2023.tde-05102023-121220

    Abstract: O controle da porosidade e do tamanho de grão é necessário para melhorar o desempenho de pastilhas combustíveis, especificamente na capacidade de reter produtos de fissão. Com o objetivo de otimizar a microestrutura de combustível sem o uso de aditivos de sinterização, pastilhas de UO2 foram sinterizadas por 3 h e 4 h a 1500 ºC, 1600 ºC e 1700 ºC.. Não foram observadas variações significativas na porosidade. O maior tamanho de grão médio medido é observado na faixa de 1700 ºC por 4 h, estabelecendo essa condição como ótima. Tal condição foi empregada em pastilhas com razão O/U 2,15 e 2,26 e também em pastilhas oriundas de misturas de UO2 com pós de U3O8 obtidos pela oxidação do UO2 a 400ºC (U3O8 verde) e a 1300ºC (U3O8 queimado) ao ar. A finalidade é avaliar o efeito destas condições no desenvolvimento da microestrutura no processo de sinterização. A adição de U3O8 na proporção de 10% não resultou em incrementos no tamanho de grão. Essa observação foi aplicável tanto ao U3O8 verde quanto ao U3O8 queimado. Apesar da diferença significativa de superfície específica dos dois pós, essa diferença não se influiu no tamanho final dos grãos. Em ambas as misturas, foram obtidos tamanho médio de grão e distribuição de tamanhos de grão compatíveis. Os resultados indicam que a estequiometria afetou o desenvolvimento da microestrutura, promovendo o crescimento dos grãos mesmo em atmosfera redutora. Uma relação O/U de 2,26 resultou em um tamanho médio de grão de 12,4 μm, enquanto uma relação O/U de 2,15, levou a 8,0 μm. Portanto, a sinterização de UO2 com uma relação O/U de 2,26, possivelmente devido à disposição homogênea do U3O8 em sua estrutura e à hiperestequiometria, resultou no resultado experimental mais promissor obtido neste trabalho. O tamanho de grão alcançado foi superior ao valor mínimo aceitável em termos industriais para pastilhas de UO2 pura, sem a utilização de aditivos de sinterização.

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  • IPEN-DOC 30115

    VILLANI, DANIEL ; SAVI, M.; RODRIGUES JUNIOR, O. ; POTIENS, M.P.A. ; CAMPOS, L.L. . Computed Tomography Imaging analysis of a fused filament fabrication (FFF) 3D printed neck-thyroid phantom for multidisciplinary purposes. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 42.

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  • IPEN-DOC 30114

    GODELI NETO, JULIO; POLETTI, MARTIN E.; CUNHA, DIEGO M. da; POTIENS, MARIA da P.A. . Computational evaluation of the bucky components influence on the estimation of normalized glandular dose in digital mammography. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 69.

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  • IPEN-DOC 30113

    ALMEIDA JUNIOR, J.N. ; POTIENS, M.P.A. ; RODRIGUES JUNIOR, O. . Characterization of a 3D Prototyping Semi-Automated Filter Holder System for RQR and RQA radiation qualities. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 172.

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  • IPEN-DOC 30112

    RODRIGUES, PRISCILA ; BURIN, ANA ; BARBEZAN, ANGELICA ; TALACIMON, CRISTHIAN ; ILCA, MEDEIROS ; TEODORO, LARA E.H. ; RIGO, MARIA ; GESSERAME, MAYSA ; TAVARES, PAULO ; NOGUEIRA, THUANY ; ROSERO, WILMMER ; RODRIGUES JUNIOR, ORLANDO ; ZEITUNI, CARLOS ; ROSTELATO, MARIA . Characterization of FXG dosimeters with gold nanoparticles for brachytherapy applications. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 67.

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  • IPEN-DOC 30111

    SILVA, IANDRA T.; PIERI, KAREN; ALBINO, LUCAS D.; FONTANA, THIAGO S.; SANTOS, MATHEUS F. dos; ROESLER, ERNESTO; ASFORA, VIVIANE K.; OLIVEIRA, CHARLES; GONCALVES, JOSEMARY A.C. ; BUENO, CARMEN C. ; KHOURY, HELEN J.. Characterization of a commercial PIN diode for radiotherapy photon beam dosimetry. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 47.

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  • IPEN-DOC 30110

    SUZART, KAROLINE F. ; PEREIRA, MARIA da C. ; MESQUITA, CARLOS H. de ; POTIENS, MARIA da P.A. . Development and Characterization of the CsI:Tl scintillator grown by the Bridgman technique for use as a radiation detector. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 46.

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  • IPEN-DOC 30109

    TAVARES, P.V.S. ; DINIZ, R.E. ; RODRIGUES JUNIOR, O. ; CAMPOS, L.L. . Attenuation images of Optical CT using Fricke xylenol solution for dose mapping in radiotherapy. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 61.

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  • IPEN-DOC 30108

    OLIVEIRA, LUCAS N. de ; NASCIMENTO, ERIBERTO O.; ANTONIO, PATRICIA L. ; CALDAS, LINDA V.E. . A new natural detector (Curcuma Longa L.) for photodynamic therapy (PDT) measurements with blue LED irradiations: Application of Convolutional Neural Networks (CNN) and Multilayer Perceptron (MLP). In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 71.

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  • IPEN-DOC 30098

    ARAUJO, ARIANA O.M. de . Caracterização de placas de materiais compósitos de polietileno reforçado com fibras de coco de babaçu, casca de castanha e piaçava / Comparison of the mechanical strength between the plates of composite materials of polyethylene reinforced with babassu coconut fibers, chestnut shell and piassava . 2023. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 62 p. Orientador: Nelson Batista de Lima. Coorientador: Rene Ramos de Oliveira. DOI: 10.11606/D.85.2023.tde-24082023-080349

    Abstract: Atualmente, é de grande relevância a preocupação ambiental associada com o reaproveitamento de resíduos agroindustriais, este tema tem aumentado o interesse por compósitos poliméricos mais ecologicamente corretos, para tanto a união de pesquisadores com estas questões ambientais tem gerado um novo compo de pesquisa. Este trabalho visa a obtenção de placas de fibras vegetais, proveniente da incorporação do polímero PBAT/PLA (ECOVIO®) com as fibras de coco de babaçu, fibras de casca de castanha e fibras de piaçava, onde 75% dessas fibras são provenientes de resíduos. As fibras do coco de babaçu, fibras de casca de castanha e fibras de piaçava foram caracterizadas, reduzidos a pó fino e submetidas aos ensaios: mecânico, DSC (Differential Scanning Calorimetry) e DRX. A preparação da blenda polimérica Ecovio foi realizada por meio da técnica de mistura mecânica no estado fundido, utilizando uma extrusora dupla-rosca com matriz plana acoplada e máquina de moldagem por injeção, para a obtenção das placas para confecção dos corpos de prova. As amostras de compositos foram avaliadas por ensaio mecânico, DRX (Difração de Raios X) e DSC (Differential Scanning Calorimetry) e as propriedades foram discutidas. O compósito PBAT/PLA/ (Poli butileno adipato co-tereftalato / poli ácido lático) reforçados com fibra de Piaçava apresentou propriedades mecânicas superiores as demais fibras. O ensaio de difração de raios x (DRX) mostrou picos característicos de fibra de origem vegetal, ou seja, as curvas de raio x apresentaram os picos característicos dos materiais, não demonstrando alteração dos mesmos no momento de processamento. No ensaio de resistência à tração a fibra que apresentou um melhor resultado a resistência foi a piaçava. A partir dos exemplos expostos acerca do uso da piaçava na composição de materiais, verifica-se sua potencialidade de aplicação na construção civil e mobiliários, contribuindo diante de um cenário mais sustentável.

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  • IPEN-DOC 30097

    BALDUINO, GLEISON W. . Prospecção tecnológica de ciclos de combustível e reatores nucleares para emprego em propulsão naval / Technological prospecting of fuel cycles and nuclear reactors for use in naval propulsion . 2023. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 155 p. Orientador: Delvonei Alves de Andrade. DOI: 10.11606/D.85.2023.tde-10112023-164630

    Abstract: Este trabalho apresenta um estudo sistematizado de ciclos de combustível de fusão e de fissão nuclear com foco na identificação do estado da arte em soluções de reatores nucleares de fissão e de fusão nuclear que tenham potencial de emprego em propulsão naval. Neste intento são descritos diversos ciclos de combustíveis nucleares tanto para reações de fissão nuclear bem como para reações de fusão nuclear. Em meio a cada ciclo são apresentadas soluções de reatores nucleares em diversos níveis de maturidade tecnológica. Cada solução é então analisada e classificada quanto a sua maturidade tecnológica, maturidade produtiva, estágio de desenvolvimento, possibilidade de escalonamento e portabilidade para o emprego naval, adequação quanto a requisitos de doutrinas nacionais de desenvolvimento, quanto ao passivo ambiental vinculado e quanto a dificuldade tecnológica de cada solução tendo em conta o parque industrial nacional. As soluções são organizadas em tabelas e discutidas, pontos positivos para emprego na propulsão naval são apresentados, itens, soluções e linhas de desenvolvimento tecnológico são sugeridos e um prognóstico futuro é apresentado ao final do trabalho, oferecendo ao leitor um panorama atualizado de soluções tecnológicas e de rumos do desenvolvimento tecnológico em andamento.

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  • IPEN-DOC 30096

    BARBOSA, INGRID A.B. . Binder-free textile PAN-based electrodes for aqueous and glycerol-based electrochemical supercapacitors / Eletrodos à base de PAN têxtil sem aglutinantes para supercapacitores eletroquímicos em eletrólitos aquosos e à base de glicerol . 2023. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 135 p. Orientador: Rubens Nunes de Faria Junior. DOI: 10.11606/D.85.2023.tde-06102023-140822

    Abstract: Amidst different types of energy storage devices, electrochemical supercapacitors have received considerable attention as they close the gap between electrolytic capacitors and batteries. This work addresses electric double-layer capacitors (EDLCs), a type of electrochemical supercapacitor, and has been divided into two parts. In the former, the production and characterization of activated carbon fiber-felt (ACFF) electrodes derived from textile PAN-based fiber have been provided. In the latter, the electrochemical characterization of EDLCs in aqueous electrolytes (acidic and alkaline) and in three types of glycerol-based electrolytes have been investigated. Binder-free ACFF electrodes have a high specific surface area of 1875 m2 g-1, containing 87% of the total volume of pores as micropores (maximum pore width of 3 nm), and a modal distribution of 1.2 nm. Electrochemical impedance spectroscopy, cyclic voltammetry, and galvanostatic charge-discharge techniques were carried out in a symmetric two-electrode setup at room temperature. The results showed that ACFF electrodes are suitable for acidic and alkaline aqueous electrolytes as well as the choline chloride-glycerol hybrid electrolyte (ChCl:GLY) at a molar ratio of 3:1. Among aqueous electrolytes, H2SO4 2 mol L-1 had the most satisfactory electrochemical performance in terms of power and energy, followed by KOH 2 mol L-1 and H2SO4 1 mol L-1. Among the glycerol-based electrolytes investigated in this work, ChCl:GLY (3:1) has the most comparable performance to aqueous electrolytes. Although power density is still limited due to high internal resistance, ChCl:GLY (3:1) is heat-resistant and a promising alternative electrolyte for supercapacitors applications, especially given that glycerol is a by-product of FAME (fatty acid methyl ester) biodiesel.

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  • IPEN-DOC 30095

    BARBOSA, ANDREY da S. . Membranas de troca aniônica baseadas em polietileno aplicadas como eletrólito polimérico alcalino em dispositivos eletroquímicos / Anion-exchange membranes based on polyethylene as an alkaline polymer electrolyte for electrochemical devices . 2023. Tese (Doutorado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 172 p. Orientador: Elisabete Inacio Santiago. DOI: 10.11606/T.85.2023.tde-27122023-172554

    Abstract: As membranas de troca aniônica (AEM) são materiais ionoméricos usados em dispositivos eletroquímicos alcalinos, como células a combustível, eletrolisadores, baterias entre outros. Uma rota simples de sintetizar AEMs é conhecida como enxerto induzido por radiação (RIG), que frequentemente é dividida em dois métodos - pré-irradiação (PIM) e simultâneo (SM). O presente estudo está divido em três etapas, primeiro, é fornecida uma investigação sistemática do efeito de cada método RIG nas propriedades de AEMs baseadas em polietileno de baixa densidade (LDPE). As AEMs possuem a mesma estrutura molecular, mas propriedades distintas devido às diferenças no grau de reticulação, que é capaz de afetar o transporte hídrico nas AEMs e desempenho de célula a combustível de H2/O2. A segunda etapa compreende uma análise exploratória do método PIM através da dose de radiação, temperatura e atmosfera. A caracterização detalhada das AEMs mostra efeitos marcantes causados pelas condições de pré-irradiação nas propriedades de AEMs baseadas em LDPE. Tais condições têm forte influência no tipo, quantidade e decaimento dos radicais formados durante e após a irradiação, afetando posteriormente o processo de enxertia (uma diferença de 190% é observada). Os resultados experimentais evidenciam que controlar tanto a temperatura de irradiação quanto da atmosfera, minimiza a degradação causada pela radiação, e melhora a estabilidade química da AEM em 120%. Finalmente, a partir dos conhecimentos obtidos nas etapas anteriores, uma AEM ultrafina baseada em polietileno de alta densidade (HDPE) é desenvolvida. Esta AEM compõe um reator eletroquímico de fluxo para oxidação direta de metano via íons carbonato a produtos oxigenados. Parâmetros operacionais como potencial aplicado (0,7-1,4V), temperatura (40-80 ºC), fluxo de metano (50-100 mL min-1), e quantidade de catalisador no ânodo (1-3 mg cm-2) são estudados em um reator de área ativa de 5 cm2 como base para construir um reator de 25 cm2. O reator de 5 cm2 é capaz de gerar metanol como produto majoritário com taxa de 73 μmol g-1 h-1 e seletividade de 75%. O escalonamento do reator para 25 cm2 resulta em 368 μmol g-1 h-1 de metanol com seletividade de 95%. É a primeira vez que um estudo original e sistemático é realizado nas condições descritas, avaliando desde as etapas de síntese de AEMs e correlacionado suas propriedades com testes eletroquímicos.

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  • IPEN-DOC 30107

    RODRIGUES, PRISCILA ; BURIN, ANA ; TALACIMON, CRISTHIAN ; AMARAL, ILCA MARLI ; PEREIRA, JULIO ; TEODORO, LARA E.H. ; RIGO, MARIA ; TAVARES, PAULO ; MARTINS, ANNA; RODRIGUES JUNIOR, ORLANDO ; SOUZA, CARLA de ; ZEITUNI, CARLOS ; ROSTELATO, MARIA . Validation of Fricke xylene gel dosimetry through comparisons between MCNP and TOPAS simulations. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 175.

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  • IPEN-DOC 30106

    OTERO, ANDRE G.L. ; MARUMO, JULIO T. ; JUNIOR POTIENS, ADEMAR J. . A methodology for automated radioactive waste characterization. In: INTERNATIONAL CONFERENCE ON DOSIMETRY AND ITS APPLICATIONS, 4th, October 16-20, 2023, Valencia, Spain. Abstract... Valencia, Spain: ISIRYM, 2023. p. 174.

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  • IPEN-DOC 30094

    BARRAVIERA, GUILHERME de C. . Obtenção e caracterização de nitreto de silício com microestrutura macroporosa para aplicação biomédica / Obtaining and characterization silicon nitride with macroporous microstructure for biomedical application . 2023. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 76 p. Orientador: Cecilia Chaves Guedes e Silva. DOI: 10.11606/D.85.2023.tde-05102023-102841

    Abstract: Cerâmicas porosas de nitreto de silício obtidas por processamento coloidal são bastante promissoras em aplicações na área médica, pela sua possibilidade de combinação de propriedades mecânicas e biológicas similares as do osso. Dessa forma, esse trabalho visa obter cerâmicas de nitreto de silício porosas e bioativas para preenchimentos ósseos. Para tanto, utilizaram-se cálcia e sílica como aditivos de sinterização, além de gelatina como agente de conformação para o processamento por gelcasting. Medidas de potencial zeta de suspensões contendo Si3N4, CaCO3 (utilizado como precursor do CaO) e SiO2 foram realizadas, considerando diferentes valores de pH (8 a 12) e concentrações de dispersante (0,5 a 2 % em massa). Além disso, avaliou-se o comportamento das suspensões contendo lauril sulfato de sódio, utilizado como espumante para formação de porosidade. Ainda, amostras foram preparadas utilizando diferentes teores de gelatina, diferentes temperaturas de sinterização e, também, utilizando pós de nitreto de silício calcinado e não calcinado. Assim, as amostras foram analisadas quanto a sua densidade, propriedades mecânicas e, para a análise da microestrutura, utilizou-se microscopia eletrônica de varredura e difratometria de raios X. Os resultados mostraram que pH alcalino, próximo a 10,5 e a adição de 2% (em massa) do dispersante poliacrilato de amônio promoveram maior estabilidade e condições de dispersão. Observou-se, ainda, que a concentração micelar crítica do espumante foi de 0,2% em massa, indicando a quantidade ideal de lauril sulfato de sódio a ser utilizada. Notou-se que temperaturas inferiores a 1600 ºC não promoveram uma total transformação α→β. Além disso, temperaturas mais altas comprometeram a microporosidade do material, tornando as paredes dos poros mais densas. A microestrutura obtida caracterizou-se por grãos alongados de β-Si3N4, contendo rosenhahnita como fase secundária. A partir das condições experimentais adotadas, foi possível obter amostras com poros interconectados e com porosidade acima de 60 %. Os ensaios mecânicos mostraram que as amostras sinterizadas entre 1450 e 1600ºC apresentaram bons resultados de resistência à compressão, comparando com o osso cortical, sendo que temperaturas maiores provocaram um aumento da mesma. Ainda, os materiais produzidos com pó previamente calcinado apresentaram microestrutura com grande quantidade de poros isolados. Isso demostra que os materiais obtidos, com o pó não calcinado, são promissores para aplicações como implantes osteocondutivos.

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  • IPEN-DOC 30093

    CALDAS NETO, ALVARO B. . Desenvolvimento de estratégias para descomissionamento de reatores nucleares de pequeno porte no Brasil / Development of strategies for decommissioning small nuclear reactors in Brazil . 2023. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 291 p. Orientador: Antonio Teixeira e Silva. DOI: 10.11606/D.85.2023.tde-05102023-101722

    Abstract: Nos últimos anos, o Brasil tem se empenhado em fortalecer sua estrutura regulatória e o setor nuclear brasileiro como parte de sua visão estratégica para enfrentar os desafios futuros no setor energético. Um desses desafios é a busca por soluções sustentáveis e de baixa emissão de carbono, a fim de atingir as metas de descarbonização e mitigar os impactos das mudanças climáticas. Nesse contexto, o País vislumbra a possibilidade de investir em reatores nucleares como uma fonte eficiente de produção de energia. Todavia, esses reatores, ao término da fase de operação, seja pelo fim de sua vida útil, ou no caso de retirada precoce de operação por acidente, ou por decisão da organização operadora, são descomissionados, em um processo que envolve a descontaminação e o desmantelamento da estrutura e a gestão adequada dos rejeitos radioativos gerados. O processo de descomissionamento é composto por atividades técnicas e administrativas que visam desligar uma instalação nuclear, incluindo a remoção total ou parcial do controle regulatório. Em virtude da complexibilidade envolvida nesse processo, a AIEA recomenda que o descomissionamento de instalações nucleares deva ser executado como um projeto de engenharia, com a diferença que este envolve equipamentos e materiais radioativos que precisam ser manuseados e controlados conforme os pré-requisitos técnicos e regulatórios, colocando-os em condição que não represente um risco inaceitável. O projeto de descomissionamento de uma instalação nuclear começa com a elaboração de um plano preliminar de descomissionamento ainda na fase de projeto de construção da instalação, que acompanha toda a fase de construção e operação. Ao final da vida útil da instalação, é elaborado um plano final de descomissionamento, que deve ser aprovado pelo órgão regulador competente antes do início das atividades de descomissionamento. Assim, o descomissionamento pode levar décadas para ser planejado e executado, além de exigir um investimento significativo para alcançar seu objetivo. Nesse contexto, o projeto de descomissionamento deve ser conduzido por meio de uma estratégia específica, demonstrando sua viabilidade de implementação, alinhada com a estrutura regulatória e considerações técnicas, administrativas, sociais, ambientais e econômicas do país em questão. Com o aumento das atividades nucleares previstas nas políticas e estratégias nacionais e considerando as recentes mudanças regulatórias, foi desenvolvido nesse trabalho um conjunto de estratégias para o planejamento das atividades de descomissionamento de reatores nucleares de pequeno porte já na fase de projeto de construção. Essas estratégias, bem planejadas e sistemáticas, abrangem todo o ciclo de vida do reator deste a sua fase inicial de projeto até o seu descomissionamento e foram embasadas por meio de uma pesquisa bibliográfica sobre o tema e utilizando as técnicas do processo de avaliação de risco descritas na norma ABNT ISO/IEC 31010. Além disso, elas foram fundamentadas em boas práticas internacionais e em recomendações da AIEA, visando direcionar o descomissionamento de reatores nucleares de pequeno porte no Brasil.

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  • IPEN-DOC 30092

    CAMPOS, ROGERIO C. de . Modelagem e análise termo-hidráulica do reator de pesquisa IEA-R1 utilizando o código RELAP / Thermo-hydraulic modeling and analysis of the IEA-R1 research reactor using the RELAP code . 2023. Dissertação (Mestrado em Tecnologia Nuclear) - Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, São Paulo. 114 p. Orientador: Delvonei Alves de Andrade. DOI: 10.11606/D.85.2023.tde-06102023-152333

    Abstract: Este trabalho apresenta a elaboração de um modelo termo-hidráulico com o código RELAP para o reator IEA-R1, contemplando a piscina, o núcleo do reator, toda tubulação e válvulas do circuito primário, o tanque de decaimento, as duas bombas de circulação principal, os dois trocadores de calor e o Sistema de Refrigeração de Emergência. Todas as partes mais importantes dos circuitos elaborados são descritos detalhadamente e são apresentadas diversas simulações demonstrando o funcionamento satisfatório do modelo produzido. A vazão em regime permanente resultantes nos canais de refrigeração dos elementos combustíveis apresentou uma diferença de aproximadamente 6,4% em relação aos dados experimentais de vazão, assim como os canais abertos entre elementos adjacentes apresentam a entrada lateral de fluxo da piscina para o núcleo com maior intensidade na região inferior. Também foi realizada uma série de simulações que apresenta a distribuição de temperatura ao longo dos componentes do núcleo, onde a comparação entre um canal médio e um canal conservativo demonstrou incrementos de temperatura resultantes entre 85,6 e 88,4%, próximos ao valor teórico esperado de 84,4%. Os modelos dos trocadores de calor reproduziram de forma precisa o comportamento das temperaturas, tanto para contracorrente quanto para correntes paralelas. Finalmente, foi realizada uma simulação de um acidente de perda de vazão lenta no núcleo que apresentou fidedignamente a fenomenologia do evento: a queda de temperatura após a perda de vazão e desligamento do reator, seguida da abertura da válvula de circulação natural e a inversão da direção do escoamento no núcleo do reator. A comparação com resultados experimentais mostrou diferenças de temperaturas de 2,3ºC para o fluido e de até 4ºC para o revestimento. Em suma, o modelo RELAP desenvolvido para o IEA-R1 foi capaz de replicar os principais sistemas e equipamentos do reator, permitindo simulações para avaliações sistêmicas.

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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.

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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.

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Tipo de publicação: Texto completo de evento

Ano de publicação: 2015

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ATENÇÃO!

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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.