Navegação IPEN por ano de publicação "2022"

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  • IPEN-DOC 28691

    KHAN, ZAHID U.; UCHIYAMA, MAYARA K.; KHAN, LATIF U.; ARAKI, KOITI; GOTO, HIRO; FELINTO, MARIA C.F.C. ; SOUZA, ANA O. de; BRITO, HERMI F. de; GIDLUND, MAGNUS. Wide visible-range activatable fluorescence ZnSe:Eu3+/Mn2+@ZnS quantum dots: local atomic structure order and application as a nanoprobe for bioimaging. Journal of Materials Chemistry B, v. 10, n. 2, p. 247-261, 2022. DOI: 10.1039/d1tb01870a

    Abstract: The development of QDs-based fluorescent bionanoprobe for cellular imaging fundamentally relies upon the precise knowledge of particle–cell interaction, optical properties of QDs inside and outside of the cell, movement of a particle in and out of the cell, and the fate of particle. We reported engineering and physicochemical characterization of water-dispersible Eu3+/Mn2+ co-doped ZnSe@ZnS core/shell QDs and studied their potential as a bionanoprobe for biomedical applications, evaluating their biocompatibility, fluorescence behaviour by CytoViva dual mode fluorescence imaging, time-dependent uptake, endocytosis and exocytosis in RAW 264.7 macrophages. The oxidation state and local atomic structure of the Eu dopant studied by X-ray absorption fine structure (XAFS) analysis manifested that the Eu3+ ions occupied sites in both ZnSe and ZnS lattices for the core/shell QDs. A novel approach was developed to relieve the excitation constraint of wide bandgap ZnSe by co-incorporation of Eu3+/Mn2+ codopants, enabling the QDs to be excited at a wide UV-visible range. The QDs displayed tunable emission colors by a gradual increase in Eu3+ concentration at a fixed amount of Mn2+, systematically enhancing the Mn2+ emission intensity via energy transfer from the Eu3+ to Mn2+ ion. The ZnSe:Eu3+/Mn2+@ZnS QDs presented high cell viability above 85% and induced no cell activation. The detailed analyses of QDs-treated cells by dual mode fluorescence CytoViva microscopy confirmed the systematic color-tunable fluorescence and its intensity enhances as a function of incubation time. The QDs were internalized by the cells predominantly via macropinocytosis and other lipid raft-mediated endocytic pathways, retaining an efficient amount for 24 h. The unique color tunability and consistent high intensity emission make these QDs useful for developing a multiplex fluorescent bionanoprobe, activatable in wide-visible region.

    Palavras-Chave: quantum dots; zinc selenides; europium; manganese; zinc sulfides; biological functions; cell membranes; particle interactions

  • IPEN-DOC 28433

    NUNES, R.F.; TOMINAGA, F.K. ; BORRELY, S.I. ; TEIXEIRA, A.C.S.C.. UVA/persulfate-driven nonylphenol polyethoxylate degradation: effect of process conditions. Environmental Technology, v. 43, n. 2, p. 286-300, 2022. DOI: 10.1080/09593330.2020.1786166

    Abstract: UV/persulfate (UV/PS) technologies have gained increased attention as efficient alternatives for removing pollutants from different classes, although processes based on the UVA-driven S2O2−8 (PS) activation have not yet been discussed in the literature for the removal of the nonionic surfactant nonylphenol polyethoxylate (NPEO). The present study investigated the simultaneous effect of the initial persulfate concentration ([PS]0) and specific photon emission rate (EP,0) on NPEO degradation by UVA/PS following a Doehlert experimental design. The results for [NPEO]0 = (4.65 ± 0.15) mg L−1 indicated more than 97.8% NPEO removal after 2 h, with pseudo first-order specific degradation rate (kobs) of 0.0320 min−1, for [PS]0 = 7.75 mmol L−1 and EP,0 = 0.437 μmol photons L−1 s−1. Under these conditions, NPEO half-life time was about 22 min, and the EC50-48 h (% v/v) values for Daphnia similis before and after treatment did not differ significantly. Higher values of EP,0 would influence NPEO removal for [PS]0 not higher than 8–10 mmol L−1, although lower degradation efficiencies were obtained with higher [NPEO]0 or real wastewater, except for longer reaction times. Additionally, UVA/PS showed to be efficient for tensoactivity removal, despite the negligible total organic carbon (TOC) removal achieved. Finally, UVC and UVA resulted in NPEO degradation higher than 96% and similar tensoactivity removals when UVA/PS was conducted under optimal conditions ([PS]0 = 10 mmol L−1; EP,0 = 0.324 μmol photons L−1 s−1), suggesting that UVA radiation available in solar light could be advantageously employed for NPEO removal at concentrations usually found in wastewater.

    Palavras-Chave: surfactants; pollution control; biodegradation; persulfates; ultraviolet radiation; surface tension

  • IPEN-DOC 28500

    MAZZILLI, BARBARA P. ; LAVIERI, LETICIA G.S. ; SOARES, JOSIANE S. ; ROCHA, FLAVIO R. ; ANGELINI, MATHEUS ; FAVARO, DEBORAH I.T. . Trace and major elements, natural and artificial radionuclides assessment in bottom sediments from Tietê River basin, São Paulo State, Brazil: part III. Journal of Radioanalytical and Nuclear Chemistry, v. 331, n. 1, p. 129-144, 2022. DOI: 10.1007/s10967-021-08094-z

    Abstract: This paper aims at quantifying natural and artificial radionuclides, trace and major elements in sediments collected along the Tietê River basin. The results obtained for Cd, Cr, Cu, Ni and Zn, indicated that the region of “High Tietê” is highly polluted, followed by the region of “Middle Tietê” and the region of “Low Tietê” does not present evidence of contamination. The natural radionuclide concentrations were of the same order of magnitude of world average values and can be defined as basal levels of the region. Cesium-137 activity concentration ranged from 0.22 ± 0.08 Bq kg−1 to 0.96 ± 0.12 Bq kg−1.

    Palavras-Chave: rivers; sediments; contamination; elements; heavy metals; radioisotopes; trace amounts

  • IPEN-DOC 28662

    YAMAGATA, CHIEKO ; LEME, DANIEL R. ; RODRIGUES, VANESSA G. ; ERETIDES, GABRIEL T. ; RODAS, ANDREA C.D.. Three routes for the synthesis of the bioceramic powder of the CaO-MgO-SiO2 system. Ceramics International, v. 48, n. 7, p. 9681-9691, 2022. DOI: 10.1016/j.ceramint.2021.12.169

    Abstract: We report three routes for the synthesis of CaO-MgO-SiO2 (CMS) bioceramic powder using different Si sources and synthesis procedures. The ceramic powders were synthesized from Na2SiO3 waste solution by the sol-gel process combined with co-precipitation (synthesis route I and synthesis route II), and from TEOS (tetraethyl orthosilicate) by conventional sol-gel (synthesis route III). Ceramic powders of the CMS multiphase system were obtained, including diopside, wollastonite, akermanite, monticellite and merwinite, which are suitable for application as biomaterial. These powders were sintered at 1200 °C for 2 h to obtain the CMS ceramics. The ceramics mostly contained diopside and wollastonite crystalline phases. Those ceramics when submitted to cytotoxicity tests revealed to be non-cytotoxic, according to ISO10993-5:2009. The ceramics were tested for in vitro bioactivity while soaked in simulated body fluid (SBF) solution. After 14 days, the presence of hydroxyapatite particles on the surface of ceramics was confirmed by Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM) micrographs. The surfaces were completely covered with hydroxyapatite, after 21 days. In summary, CaO-MgO-SiO2 (CMS) ceramic powder derived from three routes of synthesis have potential application in the biomedical area. However, further in-vitro and in-vivo studies are needed.

    Palavras-Chave: synthesis; ceramics; biological materials; sol-gel process; coprecipitation

  • IPEN-DOC 28676

    ROSA, MYCHELLE M.L. ; MAIHARA, VERA A. ; TADDEI, MARIA H.T.; CHEBERLE, LUAN T.V.; AVEGLIANO, ROSEANE P. ; SILVA, PAULO S.C. . The use of total diet study for determination of natural radionuclides in foods of a high background radiation area. Journal of Environmental Radioactivity, v. 242, p. 1-9, 2022. DOI: 10.1016/j.jenvrad.2021.106793

    Abstract: The activity concentrations of 40K, 210Pb, 210Po, 226Ra, 228Ra, 228Th, 230Th, 232Th, 234U, and 238U were determined in 82 food samples, grouped into 20 food groups according to the Brazilian Total Diet, which reflects the dietary habits of a population, for the rural and urban areas of Poços de Caldas city, a High Background Radiation Area. The highest activity concentration found in the food samples was due to 40K being present in all types of food. Among the other radionuclides, high activity concentrations were found for 210Pb in beans and salt, 210Po in fish, 226Ra and 228Ra in nuts and seeds. The main food groups that contributed most to the effective dose, in urban and rural regions, were beans and beverages. The effective doses, due to the ingestion of the analysed food groups, were of 0.44 and 0.60 mSv y−1 and the lifetime cancer risks were 1.6 × 10−3 and 2.3 × 10−3 for the urban and rural Poços de Caldas population, respectively.

    Palavras-Chave: diet; natural radioactivity; food; ingestion; background radiation

  • IPEN-DOC 28700

    THIPE, VELAPHI C. ; MENTOR, SHIREEN; LIMA, CAROLINE S.A. ; FREITAS, LUCAS F. ; FONSECA, ANA C.M.; NOGUEIRA, KAMILA M. ; RODRIGUES, ADRIANA S. ; BATISTA, JORGE G.S. ; FERREIRA, ARYEL H. ; LUGAO, ADEMAR B. . The role of probiotics in maintaining immune homeostasis. In: DWIVEDI, M.K. (Ed.); AMARESAN, N. (Ed.); SANKARANARAYANAN, A. (Ed.); HELEN KEMP, E. (Ed.). Probiotics in The Prevention and Management of Human Diseases. London, United Kingdom: Academic Press, 2022. p. 41-58, cap. 3. (A Scientific Perspective). DOI: 10.1016/B978-0-12-823733-5.00024-6

    Abstract: The immune system is a complex architecture of a collective and coordinated network regulated by various pathways to thermodynamically maintain immune homeostasis. The gut microbiota plays a pivotal role that offers significant stimuli (i.e., gut-brain, gut-lung, and gut-liver axis) for both innate and adaptive immunity, mediating immune and metabolic homeostasis. An intricate correlation between changes in the gut microbiota (dysbiosis) and common diseases/disorders have been attributed to the invasion of pathogens, constant use of antibiotics, and hypercytokinemia—a hallmark of immune homeostasis imbalance. These factors contribute to the severity of inflammatory diseases such as cardiovascular diseases, neurological disorders, and of late the coronavirus disease, Covid-19. Probiotics (Lactobacillus spp. and Bifidobacterium spp.) have been considered as alternative and/or adjuvant therapeutic in restoring the balance of gut microbiota for maintaining immune homeostasis and integrity. The probiotics catalyze dietary fibers and proteins to generate short-chain fatty acids and tryptophan to promote antiinflammatory cytokines, reduce epithelium permeability, reinforcing immunity in the gut mucosa, and regulating the systemic immune response. Herein, we review our overarching understanding of current applications of probiotics in amelioration of gut microbiome, and the improvement of gut barrier function and maintaining immune homeostasis. We also highlight clinical trials on probiotics with reported results for the treatment of inflammatory diseases. Additionally, the looming global Covid-19 pandemic makes it prudent to highlight the role of probiotics in both the innate and adaptive human immune responses, especially amid the Covid-19 vaccination paradigm.

  • IPEN-DOC 28759

    MAGALHAES, EVELLYN S.; KUMADA, DANIEL K.; WETTER, NIKLAUS U. ; KASSAB, LUCIANA R.P.; ROSSI, WAGNER de . The influence of the different parameters used for the production of double line waveguides in Nd3+ doped TeO2-ZnO glasses by fs laser writing. In: GARCIA-BLANCO, SONIA M. (Ed.); CHEBEN, PAVEL (Ed.) SPIE PHOTONICS WEST; SPIE OPTO, January 22 - February 28, 2022, San Francisco, CA, USA. Proceedings... Bellingham, WA, USA: SPIE, 2022. p. 120040Z-1 - 120040Z-7. (Proceedings SPIE 12004, Integrated Optics: Devices, Materials, and Technologies XXVI). DOI: 10.1117/12.2610189

    Abstract: Nd3+ doped TeO2-ZnO glasses with double line waveguides produced by femtosecond (fs) laser writing technique are presented. The waveguides are written directly into these glasses using a femtosecond (fs) Ti:Sapphire laser, operating at 800 nm, delivering 30 fs pulses at 10 kHz repetition rate. Each written line is formed by several collinearly overlapping lines. When double line waveguides are produced, the light is guided in between the two lines and a negative refractive index change is produced in the region of the fs laser’s focus. However, as the absorption of the material at 800 nm (4 I9/2 → 4 F 5/2 + 2 H9/2 transition of Nd3+) is in resonance with the fs laser, the heating of the material makes writing difficult. In this context, the use of several overlapping lines represents a good alternative as the velocity of the writing can be increased to avoid, heating. We report results of output mode profile, beam quality factor M2 and refractive index change for, different parameters used for the fs laser writing. Pulse energies were 15μJ for 4 and 8 overlapping lines and 30 μJ for 2, 4 and 8 overlapping lines and the writing speed was 0.5 mm/s. The present investigation evaluates the best condition for the waveguides inscription, studying the influence of different parameters used in the writing process aiming at future photonic applications.

  • IPEN-DOC 28685

    MOSCA, RODRIGO C.; SANTOS, SOFIA N. dos ; NOGUEIRA, GESSE E.C. ; PEREIRA, DAISA L. ; COSTA, FRANCIELLI C. ; PEREIRA, JONATHAS X.; ZEITUNI, CARLOS A. ; ARANY, PRAVEEN R.. The efficacy of photobiomodulation therapy in improving tissue resilience and healing of radiation skin damage. Photonics, v. 9, n. 1, p. 1-13, 2022. DOI: 10.3390/photonics9010010

    Abstract: The increased precision, efficacy, and safety of radiation brachytherapy has tremendously improved its popularity in cancer care. However, an unfortunate side effect of this therapy involves localized skin damage and breakdown that are managed palliatively currently. This study was motivated by prior reports on the efficacy of photobiomodulation (PBM) therapy in improving tissue resilience and wound healing. We evaluated the efficacy of PBM therapy on 36 athymic mice with 125I seed (0.42 mCi) implantation over 60 days. PBM treatments were performed with either red (660 nm) or near-infrared (880 nm, NIR) LEDs irradiance of 40 mW/cm2, continuous wave, fluence of 20 J/cm2 once per week. Animals were evaluated every 7 days with digital imaging, laser Doppler flowmetry, thermal imaging, µPET-CT imaging using 18F-FDG, and histology. We observed that both PBM treatments—red and NIR—demonstrated significantly less incidence and severity and improved healing with skin radionecrosis. Radiation exposed tissues had improved functional parameters such as vascular perfusion, reduced inflammation, and metabolic derangement following PBM therapy. Histological analysis confirmed these observations with minimal damage and resolution in tissues exposed to radiation. To our knowledge, this is the first report on the successful use of PBM therapy for brachytherapy. The results from this study support future mechanistic lab studies and controlled human clinical studies to utilize this innovative therapy in managing side effects from radiation cancer treatments.

    Palavras-Chave: brachytherapy; modulation; radiations; wounds; light emitting diodes; formation damage; inflammation

  • IPEN-DOC 28764

    SOUZA, ALANA G. de; KOMATSU, LUIZ G.H. ; BARBOSA, RENNAN F.S.; PARRA, DUCLERC F. ; ROSA, DERVAL S.. The effect of ZnO nanoparticles as Ag‑carrier in PBAT for antimicrobial films. Polymer Bulletin, v. 79, n. 6, p. 4031-4048, 2022. DOI: 10.1007/s00289-021-03681-2

    Abstract: Zinc oxide (ZnO) and ZnO-silver (ZnO-Ag) nanoparticles (NPs) are widely used in different fields, such as biomedicine and food packaging, due to their recognized antibacterial activity and safety for human health. In this paper, ZnO and ZnO-Ag NPs were incorporated into poly(butylene adipate-co-terephthalate) (PBAT), in two contents (0.5 and 1 wt%), to prepare antibacterial films. The NPs were characterized by TEM and FT-Raman, and the films were analyzed by FT-Raman and FTIR, mechanical properties, SEM–EDS, TGA, DSC, XRD, and antibacterial properties against Escherichia coli. The results indicate that both NPs were physically retained in the polymer structure, with a strong electrostatic interaction between the mixture components, reflecting excellent mechanical behavior. The films showed good thermal stability, without significant changes, and the nanocomposites enhanced PBAT crystallinity from 18 to 23% and 27% for PBAT-ZnO and PBAT-ZnO-Ag films, respectively. The mechanical, thermal, and crystallinity results indicated the excellent potential of NPs in biodegradable films to improve properties and expand applicability. The antimicrobial activity is higher for PBAT-ZnO-Ag films than the pristine PBAT due to the synergic effect between the NPs and the oxidation–reduction potential of each nanoparticle, where the ZnO protect and stabilized the Ag-NPs, acting as an Ag-carrier, enhancing its antimicrobial effects after the film’s preparation and allowing its applicability in biomedical products or food packaging.

  • IPEN-DOC 28678

    CARVALHO, SABRINA G.M. ; MUCCILLO, ELIANA N.S. ; FONSECA, FABIO C. ; MULLER, MICHAEL; SCHULZE-KUPPERS, FALK; BAUMANN, STEFAN; MEULENBERG, WILHELM A.; GUILLON, OLIVIER; MUCCILLO, REGINALDO . Tape-casting and freeze-drying gadolinia-doped ceria composite membranes for carbon dioxide permeation. Journal of Membrane Science, v. 648, p. 1-10, 2022. DOI: 10.1016/j.memsci.2022.120355

    Abstract: Porous ceria: 20 mol% gadolinia (20GDC) ceramic membranes were prepared by tape casting (TC) and freeze-drying (FD) techniques, obtaining ceramic matrices with randomly dispersed round pores and with an aligned pore structure, respectively. Samples were sintered at 1450 °C, followed by infiltration of molten eutectic sodium-lithium carbonates (NLC). The pore morphology of 20GDC-TC and 20GDC-FD composite membranes was evaluated by analysis of scanning electron microscopy images. The electrical resistivity was determined by electrochemical impedance spectroscopy in the 1 Hz - 10 MHz frequency range from 300 °C to 700 °C, covering the solid-to-molten NLC temperature range, showing that the aligned pore structure improved the conductivity of the ceramic matrix in addition to facilitating molten carbonate infiltration, improving the total (bulk + interfaces) electrical conductivity of the composite membrane. Permeation experiments showed high CO2 permeation rates reached 5.35 × 10−7 mol m−2 s−1 Pa−1 at 800 °C. The infiltration of molten sodium-lithium carbonate in gadolinium-doped ceria prepared by the freeze-drying technique is proposed as an optimized procedure for producing membranes for carbon dioxide separation.

    Palavras-Chave: cerium; doped materials; gadolinium oxides; molten salts; carbon dioxide; composite materials

  • IPEN-DOC 28693

    SOUZA, CARLA D. de ; BARBEZAN, ANGELICA B. ; ROSERO, WILMMER A.A. ; SANTOS, SOFIA N. dos ; CARVALHO, DIEGO V. de S. ; ZEITUNI, CARLOS A. ; BERNARDES, EMERSON S. ; VIEIRA, DANIEL P. ; SPENCER, PATRICK J. ; RIBEIRO, MARTHA S. ; ROSTELATO, MARIA E.C.M. . Synthesis, in vitro testing, and biodistribution of surfactant-free radioactive nanoparticles for cancer treatment. Nanomaterials, v. 12, n. 2, p. 1-13, 2022. DOI: 10.3390/nano12020187

    Abstract: New forms of cancer treatment, which are effective, have simple manufacturing processes, and easily transportable, are of the utmost necessity. In this work, a methodology for the synthesis of radioactive Gold-198 nanoparticles without the use of surfactants was described. The nuclear activated Gold-198 foils were transformed into H198AuCl4 by dissolution using aqua regia, following a set of steps in a specially designed leak-tight setup. Gold-198 nanoparticles were synthesized using a citrate reduction stabilized with PEG. In addition, TEM results for the non-radioactive product presented an average size of 11.0 nm. The DLS and results for the radioactive 198AuNPs presented an average size of 8.7 nm. Moreover, the DLS results for the PEG-198AuNPs presented a 32.6 nm average size. Cell line tests showed no cytotoxic effect in any period and the concentrations were evaluated. Furthermore, in vivo testing showed a high biological uptake in the tumor and a cancer growth arrest.

    Palavras-Chave: radioactivity; nanoparticles; brachytherapy; neoplasms; testing; in vivo; in vitro; gold 198; distribution

  • IPEN-DOC 28687

    MIRANDA, JURANDIR T. de; BRINGEL, FABIANA de A. ; VELOSA, ANA P.P.; PROTOCEVICH, VERONICA; FERNEZLIAN, SANDRA de M.; SILVA, PEDRO L.; CAPELOZZI, VERA L.; MATHOR, MONICA B. ; TEODORO, WALCY R.. Sterilized human skin graft with a dose of 25 kGy provides a privileged immune and collagen microenvironment in the adhesion of Nude mice wounds. PLoS One, v. 17, n. 1, p. 1-15, 2022. DOI: 10.1371/journal.pone.0262532

    Abstract: This study aimed to report the effects of different doses of ionizing radiation on inflammatory and repair stage of human skin graft adherence in Nude mice wounds. Animals were divided into transplanted with irradiated human skin grafts (IHSG) at 25 and 50 kGy (IHSG 25 kGy; IHSG 50 kGy) and non-IHSG and euthanized on the 3rd, 7th and 21st days after the surgery, by gross and microscopic changes, immunostaining for human type I collagen (Col I) and mouse Col I and Col III and inflammatory cells. We found an effectiveness of human split-thickness graft adherence in mice transplanted with IHSG 25 kGy, as well decrease in dermo-epidermal necrosis and neutrophils, lower loss of skin thickness, epithelization and neo-vascularization. Day 21 post-transplantation with IHSG 25 kGy was observed a well-preserved human skin in the border of the graft, a prominent granulation tissue in an organization by proliferated fibroblasts, Col III deposition and increased B-cells and macrophages. A complete adherence of human skin graft occurred with IHSG 25 kGy. We suggest that the ionizing radiation at 25 kGy mediates inflammation and the repair stage of human skin graft adherence in murine model, thus emerging as a potential tool in healing cutaneous wounds.

    Palavras-Chave: animal tissues; skin; grafts; ionizing radiations; radiation doses; immune reactions; collagen; wounds; burns

  • IPEN-DOC 28701

    SOUZA, ALEXANDRE P.S. ; OLIVEIRA, LUIZ P. de ; YOKAICHIYA, FABIANO; GENEZINI, FREDERICO A. ; SIQUEIRA, PAULO de T.D. ; FRANCO, MARGARETH K.K.D. . Simulação de um difratômetro de tensão residual no IEA-R1. In: SILVA, PAULO S.C. da (Org.); ZAHN, GUILHERME S. (Org.); SOUZA, FRANCISCO de A. (Org.). Contribuições do reator IEA-R1 para a pesquisa nuclear. São Paulo, SP: Blucher, 2022. p. 21-29, cap. 1. DOI: 10.5151/9786555501483-01

    Abstract: O reator nuclear IEA-R1, localizado no Instituto de Pesquisas Energéticas e Nucleares (IPEN), disponibiliza feixes de nêutrons para aplicação em técnicas de caracterização de materiais, atualmente contando com experimentos de difração de alta resolução e tomografia. Com o intuito de expandir os experimentos, aqui é apresentado um estudo prévio visando a implementação da técnica de tensão residual por difração de nêutrons. Tal escolha, deve-se à sua grande aplicabilidade às indústrias nuclear e aeronáutica, envolvendo estudos de fadiga e corrosão em ligas de Ni, Ti e aços submetidas à tensão. Além disso, as medições de tensão residual são também executadas em materiais cerâmicos, compostos intermetálicos e policristalinos. Este estudo prévio da viabilidade da implementação da técnica é baseado em simulações numéricas, em que são analisados os componentes necessários para a instalação de um difratômetro de tensão residual nas dependências do IEA-R1. Estudos sobre a geometria e componentes como filtros, monocromador, detector, fendas foram realizados por meio do método de Monte Carlo com o software McStas para estimar o posicionamento dos mesmos.

  • IPEN-DOC 28680

    REMOR, MARCELO B.; BOAS, MARCIO A.V.; SAMPAIO, SILVIO C.; DAMATTO, SANDRA R. ; STEVAUX, JOSE C.; REIS, RALPHO R. dos. Sedimentation rate and accumulation of nutrients in the Upper Paraná river floodplain. Journal of Radioanalytical and Nuclear Chemistry, v. 331, p. 1019-1027, 2022. DOI: 10.1007/s10967-021-08153-5

    Abstract: The objective was to rebuild the history of sedimentation and accumulation of nutrients rate in the Upper Paraná River floodplain. Two corers were collected and sliced at intervals of 2 cm. In the sub-samples geochronological analysis was performed by means of the isotope 210Pb, and also the quantification of organic carbon, nitrogen and phosphorus. Garças Pond presented sedimentation rate of 7.7 mm yr(−1) and Patos Pond 6.8 mm yr(−1). The flood pulse is the main regulating factor of the sedimentation rate on the Upper Paraná River floodplain. The total organic carbon derives from allochthonous origin and the limiting productivity nutrient in the system is nitrogen.

    Palavras-Chave: eutrophication; lead 210; nitrogen; nutrients; organic matter; phosphorus; sedimentation

  • IPEN-DOC 28765

    SIQUEIRA, PAULO de T.D. . Registro do encontro organizado pela AIEA sobre melhores práticas em BNCT. São Paulo: Instituto de Pesquisas Energéticas e Nucleares - CEENG, Abril, 2022. (IPEN-CEN-FRH-CEN-052-00-INFT-001-00). Restrito.

    Título do projeto: Melhores Práticas em BNCT (Terapia por Captura de Nêutrons por Boro)

    Abstract: Esta informação técnica visa apresentar um registro das atividades realizadas durante o Evento Técnico sobre as Melhores Práticas na Terapia por Captura de Nêutrons por Boro (AIEA Technical Meeting on Best Practices of BNCT), TM-BNCT 2022 realizado de forma remota com a participação de representantes de várias nações entre os dias 14 e 18 de março de 2022.

    Palavras-Chave: administrative procedures; recommendations; boron; neutron capture therapy; iaea

  • IPEN-DOC 28657

    NISTI, M.B. ; CAVALCANTE, F. ; SAUEIA, C.H.R. ; MAZZILLI, B.P. . Reducing the risk for the biota by reusing a NORM residue. Brazilian Journal of Radiation Sciences, v. 10, n. 1, p. 1-18, 2022. DOI: 10.15392/bjrs.v10i1.1715

    Abstract: All biota is exposed to natural radiation, the soil being the major source of radionuclides. Phosphogypsum (PG) is classified as a NORM residue of the phosphate fertilizer industry, often used in agriculture, as a soil conditioner. This residue is stored in stacks by the phosphate industries, potentially posing environmental risks. The aim of this study is to compare the risk for the terrestrial and aquatic biota arising from the storage of PG residue in the environment with that arising from its reuse as soil amendment. For this purpose, typical Brazilian soils amended with PG and PG itself were leached with distilled water. The concentration of natural radionuclides in the soil samples were used to evaluate the risk for terrestrial and aquatic biota, using the ERICA Tool. The results for terrestrial biota exposed to soils amended with phosphogypsum showed a risk reduction of about 85%, when compared to the exposure arising from phosphogypsum stacks. Considering the aquatic biota, the results showed a risk reduction of about 46% when comparing to radionuclide concentrations in leachates from phosphogypsum and from the soils amended with phosphogypsum. A new risk reduction assessment was performed to determine exclusively the contribution of the application of PG to the soil using the soil without PG, the risk reduction for terrestrial biota was of 99% and aquatic biota was a 74% reduction. Finally, it can be concluded that the addition of phosphogypsum in soils reduces the risk quotient related to the exposure of terrestrial and aquatic biota, showing that this is a safe practice.

    Palavras-Chave: aquatic ecosystems; e codes; gypsum; natural radioactivity; phosphates; radiation monitoring; radioecological concentration; residues; risk assessment; soils

  • IPEN-DOC 28677

    JEONG, DAUN; SECO, ROGER; EMMONS, LOUISA; SCHWANTES, REBECCA; LIU, YINGJUN; MCKINNEY, KARENA A.; MARTIN, SCOT T.; KEUTSCH, FRANK N.; GU, DASA; GUENTHER, ALEX B.; VEGA, OSCAR ; TOTA, JULIO; SOUZA, RODRIGO A.F.; SPRINGSTON, STEPHEN R.; WATSON, THOMAS B.; KIM, SAEWUNG. Reconciling observed and predicted tropical rainforest OH concentrations. Journal of Geophysical Research: Atmospheres, v. 127, n. 1, p. 1-18, 2022. DOI: 10.1029/2020JD032901

    Abstract: We present OH observations made in Amazonas, Brazil during the Green Ocean Amazon campaign (GoAmazon2014/5) from February to March of 2014. The average diurnal variation of OH peaked with a midday (10:00–15:00) average of 1.0 × 106 (±0.6 × 106) molecules cm−3. This was substantially lower than previously reported in other tropical forest photochemical environments (2–5 × 106 molecules cm−3) while the simulated OH reactivity was lower. The observational data set was used to constrain a box model to examine how well current photochemical reaction mechanisms can simulate observed OH. We used one near-explicit mechanism (MCM v3.3.1) and four condensed mechanisms (i.e., RACM2, MOZART-T1, CB05, CB6r2) to simulate OH. A total of 14 days of analysis shows that all five chemical mechanisms were able to explain the measured OH within instrumental uncertainty of 40% during the campaign in the Amazonian rainforest environment. Future studies are required using more reliable NOx and VOC measurements to further investigate discrepancies in our understanding of the radical chemistry in the tropical rainforest.

    Palavras-Chave: hydroxyl radicals; photochemistry; forests; tropical regions; amazon river; atmospheres; environment

  • IPEN-DOC 28728

    THEOPHILO, CAROLINA Y.S. ; COLABUONO, FERNANDA I.; MONTONE, ROSALINDA C.; FIGUEIRA, RUBENS C. L.; PETRY, MARIA V.; MOREIRA, EDSON G. . Quantificação de elementos tóxicos e potencialmente tóxicos em aves marinhas por meio da análise por ativação neutrônica instrumental. In: SILVA, PAULO S.C. da (Org.); ZAHN, GUILHERME S. (Org.); SOUZA, FRANCISCO de A. (Org.). Contribuições do reator IEA-R1 para a pesquisa nuclear. São Paulo, SP: Blucher, 2022. p. 273-284, cap. 28. DOI: 10.5151/9786555501483-28

    Abstract: Existem elementos químicos que são necessários para a manutenção das vias metabólicas dos organismos, quando essenciais pequenas quantidades são suficientes, porém se os elementos estão em concentrações maiores do que as necessárias ou se não são essenciais podem acabar se acumulando no organismo e trazendo malefícios. O acúmulo desses elementos pode ocorrer nos organismos marinhos por meio da alimentação ou da contaminação ambiental e pode ser um grande problema, principalmente, para os indivíduos que possuem vida longa e que estão no topo da teia trófica, como é o caso de algumas aves marinhas. Como as aves marinhas são organismos sensíveis a mudanças no meio ambiente, sendo considerado um dos grupos de vertebrados mais ameaçados devido os impactos antrópicos causados nos oceanos, esse trabalho teve como objetivo quantificar Hg e Se em penas do Petrel-gigante-do-sul (Macronectes giganteus) e Br, Cl, Cu, K, Mg, Mn, Na e V em penas do Albatroz-de- sobrancelha-negra (Thalassarche melanophris) e da Pardela-preta (Procellaria aequinoctialis) por meio da INAA. As penas de Petrel-gigante-do-sul foram coletadas no Arquipélago das Shetland do Sul, Antártica, enquanto as penas da Pardela-preta e do Albatroz-de-sobrancelhanegra foram coletadas no sul do Brasil em parceria com o Projeto Albatroz. Nas penas do Petrel-gigante-do-sul as concentrações obtidas de mercúrio variaram entre 2,6 e 14,4 mg kg-1, e a de Se, entre 1,5 e 10,4 mg kg-1. As concentrações de Hg foram mais altas do que as encontradas em estudos similares, provavelmente essa alta concentração se deve a dieta dessa espécie que é composta por presas de níveis tróficos maiores. Enquanto os resultados obtidos nas penas da Pardela-preta e do Albatroz-de-sobrancelha-negra não foram mais altos que os de outros estudos encontrados na literatura, com exceção do Br. Também, não foram encontradas diferenças significativas entre as médias dos elementos encontradas nessas duas espécies.

  • IPEN-DOC 28709

    TORRES, WALMIR M. ; BAPTISTA FILHO, B.D. ; TING, DANIEL K.S. . Projeto e validação experimental do sistema de resfriamento de emergência do reator IEA-R1. In: SILVA, PAULO S.C. da (Org.); ZAHN, GUILHERME S. (Org.); SOUZA, FRANCISCO de A. (Org.). Contribuições do reator IEA-R1 para a pesquisa nuclear. São Paulo, SP: Blucher, 2022. p. 87-96, cap. 9. DOI: 10.5151/9786555501483-09

    Abstract: Este trabalho apresenta o projeto do Sistema de Resfriamento de Emergência (SRE) do reator IEA-R1. Este sistema, com características passivas, utiliza bicos aspersores instalados em um distribuidor instalado acima do núcleo. Os bicos aspersores aspergem água sobre o núcleo em caso de ocorrência de um acidente de perda de refrigerante (LOCA) com esvaziamento da piscina. Também é apresentado o programa experimental executado para definir os parâmetros do sistema e demonstrar às autoridades de licenciamento (CNEN) que os limites de temperatura nos elementos combustíveis não são excedidos caso esse acidente ocorra. Experimentos de distribuição de vazão sobre os elementos combustíveis foram realizados usando um modelo de núcleo em escala 1x1, para definir as especificações da geometria do distribuidor e o posicionamento, quantidade e tipo de bicos aspersores, bem como a vazão total necessária para o sistema. Experimentos, com placas aquecidas eletricamente simulando fluxos de calor correspondentes à curva de calor de decaimento do núcleo após operação com potência total de 5 MW, foram realizados para medir a distribuição de temperatura de um elemento combustível na posição mais crítica do núcleo. Em todas as condições testadas, as temperaturas medidas ficaram abaixo do valor limite.

  • IPEN-DOC 28675

    SILVA, THALITA F. da; CAVALCANTE, RODRIGO P.; GUELFI, DIEGO R.V.; OLIVEIRA, SILVIO C. de; CASAGRANDE, GLEISON A.; CAIRES, ANDERSON R.L.; OLIVEIRA, FELIPE F. de; GUBIANI, JULIANA R.; CARDOSO, JULIANO C. ; MACHULEK JUNIOR, AMILCAR. Photo-anodes based on B-doped TiO2 for photoelectrocatalytic degradation of propyphenazone: identification of intermediates, and acute toxicity evaluation. Journal of Environmental Chemical Engineering, v. 10, n. 2, p. 1-15, 2022. DOI: 10.1016/j.jece.2022.107212

    Abstract: The photoelectrocatalysis (PEC) using B-doped TiO2 photo-anodes for degradation of the propyphenazone (PPZ) was investigated. For this, four different composites based on TiO2 and TiO2-x%B (x = 1, 3 or 5) were synthesized by sol-gel method and supported on titanium substrate by the dip-coating technique. The morphology, optical and electrochemical properties of photo-anodes were evaluated by SEM, TEM, XPS, TGA, DSC, XRD, FTIR, DRS, and sweep voltammetry, respectively. The influence of pH (3, 6 or 9) and electrical potential intensity (+1 V, +2 V or +3 V) used in PEC were evaluated by kinetic study. To understand the synergistic effect of the composition of the photoelectrochemical system, photolysis (PS), electrocatalysis (EC) and photocatalysis (PC) experiments were realized under comparative conditions. Doping 3% of B into TiO2 promoted a decrease in band gap energy (Ebg = 2.91 eV), thus providing better radiation absorption and greater generation of charge carriers on the surface of the photo-anode. Characterization analyzes indicate the presence of B2O3 coexisting with TiO2. The most promising results were obtained using Ti/TiO2-3%B photo-anode (vs a DSA cathode), applying + 1 V at pH 6, resulting in 91% of PPZ degradation after 60 min of PEC treatment. Toxicity tests using A. salina and L. sativa showed that the effluent generated after 2 h of PEC treatment of 30 mg L-1 of PPZ is non-toxic for the studied species. Up to 13 by-products formed during the PEC and PS treatment were detected and a proposal pathway involving possible routes of PPZ degradation were presented.

    Palavras-Chave: photocatalysis; titanium oxides; sol-gel process; inflammation; drugs; toxicity

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

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

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

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

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

Exemplo:

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

Autor: Maprelian

Título: loss of coolant

Tipo de publicação: Texto completo de evento

Ano de publicação: 2015

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

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

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

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

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

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

ATENÇÃO!

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

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

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

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


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

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

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

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

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