MICHELANGELO DURAZZO

MICHELANGELO DURAZZO

(Fonte: Lattes)

Resumo

Graduação em Engenharia Metalúrgica pelo Instituto Mauá de Tecnologia (1979), Mestre em Tecnologia Nuclear pela Universidade de São Paulo (1986) e Doutorado em Tecnologia Nuclear pela Universidade de São Paulo (2001). Atualmente é pesquisador do Instituto de Pesquisas Energéticas e Nucleares, no cargo de Gerente Adjunto de Pesquisa e Desenvolvimento do Centro do Combustível Nuclear. Orientador de Mestrado e Doutorado. Experiência na área de Engenharia de Materiais e Metalúrgica, atuando nas áreas de tecnologia de fabricação de combustíveis nucleares, cerâmicos e compósitos, técnicas de caracterização física de materiais, desenvolvimento de processos metalúrgicos para reaproveitamento de resíduos sólidos industriais e desenvolvimento de novos materiais. Coordenação de projetos de pesquisa. Membro do Instituto Nacional de Tecnologia- INCT para Reatores Nucleares Inovadores. Autor de livro intitulado "Procedues for Manufacturing Nuclear Research Reactor Fuel Elements", 2015, ISBN-13: 978-3-659-47963-2. Autor de livro intitulado "Sintering Behavior of the UO2-Gd2O3 Nuclear Fuel", 2014, ISBN-13: 978-38454-0784-5. Autor de capítulo do livro intitulado "Manufacturing Nanostructures", 2014, ISBN: 9781910086070, capítulo intitulado "Chemical Process for Synthesis of Nanostructured Materials. Autor de capítulo de livro intitulado "Radioisotopes: Applications in Physical Sciences", 2011 ISBN: 9789533075105, capítulo intitulado "Research Reactor Fuel Fabrication to Produce Radioisotopes". Autor de capítulo de livro intitulado "Advanced Fuel Pellets Materials and Fuel Rod Design for Water Cooled Reactors: IAEA-TECDOC-1654, 2010 ISBN: 9789201089106, capítulo intitulado "Studies on the Sintering Behavour of UO2-Gd2O3 Fuel Pellets". (Texto extraído do Currículo Lattes em 17 nov. 2021)

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A novel automated thickness measurement method and device for nuclear fuel plates
2024 - KOBAYOSHI, MARCELO; LEAL NETO, RICARDO M.; CARVALHO, ELITA F.U. de; RESTIVO, THOMAZ A.G.; DURAZZO, MICHELANGELO
The Nuclear and Energy Research Institute (IPEN-CNEN/SP) currently employs manual external u-shape frame micrometers with non-rotating spindles, and chamfered measuring anvils at 21 pre-defined points to control the thickness of its fuel plates. However, it is acknowledged that this method introduces the human element into the measurement process, potentially compromising result accuracy and the integrity of the fuel plates' surfaces. This research introduces a novel thickness measurement method and an accompanying automated device featuring precise movement mechanisms, data capture, transcription, and processing. Our findings emphasize the effectiveness of this new measurement system and the structural integrity of the equipment, highlighting its potential to significantly enhance both the speed and metrological reliability of dimensional control processes for nuclear fuel plates manufactured at IPEN-CNEN/SP.
Developing a nanomaterial-based 3D-printed platform
2024 - NEGAHDARY, MASOUD; LAGO, CLAUDEMIR L. do; GUTZ, IVANO G.R.; BUORO, RAFAEL M.; DURAZZO, MICHELANGELO; ANGNES, LUCIO
Overexpressed heat shock protein 90 (HSP90) has been proven as a new cancer biomarker, and its detection can be used as an auxiliary diagnosis. In this research, we designed an electrochemical aptasensor to detect this biomarker. Initially, a 3D-printed electrode was designed and produced while the electrode surface (made from a conductive carbon black/ polylactic acid (CB-PLA) filament) was improved by CO2 laser ablation. Then, the electrode surface was modified with graphene oxide (GO) and an array of frost-like gold nanocrystals (FGNCs); the results showed that the final surface covered with gold contained nano/microstructures with a mean width of ∼ 65 nm and a mean length of ∼ 509 nm. Also, a significant increase in the electrochemically active surface area was observed for modified surfaces with GO and FGNCs. Efficient immobilization of aptamer strands on the gold surface could complete the assembly of this aptasensing platform, which could detect analyte molecules in a linear range from 0.1 to 200 ng mL−1. The estimated limit of detection (LOD) and the limit of quantification (LOQ) were as low as 0.1 ng mL−1 and 0.23 ng mL−1, respectively. The performance of reproducibility (5 times), regeneration (5 times), and stability (7 days) were satisfactory (low relative standard deviation (RSD)). Also, this aptasensor showed adequate performance for selective and accurate analyte capturing in the presence of interfering agents and spiked analyte concentrations in serum samples.
Fragmentation of fuel particles in rolling U3Si2-Al dispersion fuel plates
2024 - DURRAZO, MICHELANGELO; MARCONDES, GILBERTO H.; CARVALHO, ELITA F.U. de; BARROS, GUILHERME D. de; LEAL NETO, RICARDO M.
The Nuclear and Energy Research Institute (IPEN-CNEN/SP) has recently developed a process to produce the nuclear fuel required to run the Brazilian Multipurpose Reactor (RMB), using U3Si2-Al dispersion in plate-type fuel elements. Since the late 1980s, regular production of dispersion-based fuel plates has kept the maximum fines content (<44 μm) of 20 wt%. However, IPEN’s U3Si2 powder manufacturing process typically generates fines between 25 and 30 wt%, making it necessary to discard and recycle about 5 to 10 wt% of the powder during manufacturing. The severe fines requirements necessitate careful comminution with multiple intermediate screening steps, which has a negative impact on RMB’s fuel production scalability (60 elements per year). To improve the current fines content specification for the powder, this study focuses on looking into U3Si2 particle fragmentation during fuel plate manufacturing. Quantitative microscopy methods and image analysis were employed. The findings revealed a significant increase in fines content during the rolling process, with levels reaching up to 59 wt%. Hence, to ensure high-quality dispersion, it becomes crucial to specify the fines content in the fuel plate obtained after rolling rather than just in the original powder. The results recommend that a new U3Si2 powder specification could allow a maximum fine content of 30 wt%. More research is ongoing to confirm this recommendation.
Automated thickness measurement system for nuclear fuel plates
2024 - KOBAYOSHI, MARCELO; LEAL NETO, RICARDO M.; CARVALHO, ELITA F.U. de; DURAZZO, MICHELANGELO
Thickness measurements of nuclear fuel plates manufactured at the Nuclear Fuel Center of the Nuclear and Energy Research Institute (IPEN-CNEN/SP) are currently performed using manual external U-shaped frame micrometers with non-rotating spindles and beveled measurement anvils. Results are then manually recorded on dedicated forms. To improve the efficiency and the metrological reliability of the process, a novel thickness measurement system for nuclear fuel plates was developed. This work presents a comprehensive metrological study of the newly designed measurement system, achieved through the construction of a new apparatus with automated mechanisms for synchronized movement, data capture, transcription, and processing. The study results demonstrate the metrological adequacy of the developed system and underscore the importance of the design and structural quality of the measurement equipment. Consequently, the metrological reliability of the results in the dimensional control of nuclear fuel plates is confirmed.
Manufacturing high-uranium-loaded dispersion fuel plates in Brazil
2024 - DURAZZO, MICHELANGELO; SOUZA, JOSE A.B.; CARVALHO, ELITA F.U. de; RESTIVO, THOMAZ A.G.; GENEZINI, FREDERICO A.; LEAL NETO, RICARDO M.
The Nuclear and Energy Research Institute (IPEN-CNEN/SP) has developed and made available for routine production the technology for manufacturing dispersion-type fuel elements for research reactors. However, the fuel produced is limited to a uranium loading of 2.3 gU/cm3 (U3O8) or 3.0 gU/cm3 (U3Si2). To reduce Brazil’s dependence on foreign sources of Mo-99, the Brazilian government plans to construct a new research reactor, the 30 MW open pool Brazilian Multipurpose Reactor (RMB), which will mainly produce domestic Mo-99. Low-enriched uranium fuel will be used in the RMB, and increasing uranium loading will be important to increase the reactor core’s reactivity and fuel life. Uranium loadings of 3.2 gU/cm3 for the U3O8-Al and 4.8 gU/cm3 for the U3Si2-Al are considered the technological limit and have been well demonstrated worldwide. This work aimed to study the manufacturing process of these two highly uranium-loaded dispersion fuels and redefine current procedures. Additionally, UMo-Al dispersion fuel has been extensively studied globally and is likely to be the next commercially available technology. This new fuel utilizes a dispersion of UMo alloy with 7–10 wt% Mo, resulting in a uranium loading between 6 and 8 gU/cm3. We also studied this fuel type for potential use in the RMB research reactor. This work outlines the primary procedures for manufacturing these three types of fuels and the necessary adjustments to IPEN-CNEN/SP current technology. The manufacturing process proved to be well adapted to these new fuels, requiring only minor modifications. A comparison was made of the microstructures of fuel plate meat using three types of uranium compounds. The microstructures of U3Si2-Al and U10Mo-Al dispersions were found to be adequate, while that of U3O8-Al meat deviated significantly from the concept of an ideal dispersion.
Sintering of metallic diamond alloy powders
2023 - RESTIVO, THOMAZ A.G.; NONATO, RAPHAEL B.P.; FIGUEIRA, ROSSANA R.; FERREIRA, ODIRLEI A.; PADOVANI, CLAUDIO; ARANHA, NORBERTO; BALDO, DENICESAR; SILVA, CECILIA G. e; DURAZZO, MICHELANGELO
Metallic diamond (MD) is a new alloy class which hardness was found to surpass any current alloys at more than a twofold factor, up to 2500 HV (kgf mm−2). The alloy design employs simple metallurgical principles at the so-called Lattice Occupancy Project aided by Diamoy 1.0 software. The most important aspect of the alloy project considers the maximization of chromium equivalent values by selecting metallic elements for promoting body-centred cubic structures. Forming these alloys into parts is challenging, whereas powder metallurgy techniques appear as valid processing routes. The work studies the sintering behaviour of MD-4 and 5 alloy powders, being the hardest MD ones. High energy milled powder compacts were sintered in a dilatometer up to 1500 °C for 1 h under Ar-10%H2 atmosphere. Alloy MD-5 has shown intense shrinkage starting at 1150 °C, contrasting to marginal sintering of alloy MD-4. The latter has undergone transformations from 400 °C with strong expansion, which seems to block most of the sintering retraction at higher temperatures. Alloy powder MD-5 is a good candidate as a raw material for tool parts production by powder metallurgy, which can compete with cemented carbide hard tools.
Aptasensing of beta-amyloid (Aβ(1− 42)) by a 3D-printed platform integrated with leaf-shaped gold nanodendrites
2023 - NEGAHDARY, MASOUD; VELOSO, WILLIAM B.; BACIL, RAPHAEL P.; BUORO, RAFAEL M.; GUTZ, IVANO G.R.; PAIXAO, THIAGO R.L.C.; LAGO, CLAUDIMIR L. do; SAKATA, SOLANGE K.; MELONI, GABRIEL N.; FRANCA, MESAQUE C.; OLIVEIRA, THAWAN G. de; AMEKU, WILSON A.; DURAZZO, MICHELANGELO; ANGNES, LUCIO
In this study, beta-amyloid (Aβ(1− 42)), an essential biomarker for diagnosing Alzheimer’s disease (AD), was detected via an electrochemical aptasensing platform. Here, an innovative signal transducer was developed using a CO2 laser-ablated 3D-printed electrode modified with leaf-shaped gold nanodendrites (LSG NDs, mean diameter: ~ 92 nm), which could provide an efficient interface for immobilizing aptamer strands. The modified electrode with LSG NDs exhibited an enhancement in its electrochemically active surface area about 7 times, compared with the bare electrode. This modification showed that the size, morphology, and distributions of LSG NDs in amplifying electrochemical signals might effectively provide a highly sensitive infrastructure for analyte detection. The strands of a thiol-functionalized aptamer sequence interacted with the gold surface, which created an optimized biointerface to detect Aβ(1− 42) in a linear range from 0.1 pg mL− 1 to 10 ng mL− 1 (limit of detection (LOD): 84 fg mL− 1 , (S/N = 3)). The developed aptasensor confirmed satisfactory stability, desired reproducibility and regeneration, and minimal impact of interfering agents. In addition, the application of this aptasensor was monitored via an assay of spiked analyte concentrations in 20 samples, including cerebrospinal fluid (CSF) and human serum.
Effects of aluminum distearate addition on UO2 sintering and microstructure
2022 - FREITAS, ARTUR C. de; COSTA, DIOGO R.; JARDIM, PAULA M.; LEAL NETO, RICARDO M.; CARVALHO, ELITA F.U. de; DURAZZO, MICHELANGELO
Uranium dioxide (UO2) is widely used as a fuel in commercial nuclear light-water reactors (LWRs). Rigorous control of density, pore, and grain size of UO2 pellets are important prerequisites for fuel performance. Solid lubricants, frequently used in pellets manufacturing, minimize structural defects on compaction such as cracks and end-capping, promoting grain growth during sintering. This work presents and discusses the effects of the aluminum distearate (ADS) addition on the sintering behavior and microstructure of UO2 fuel pellets. UO2 and UO2-0.2wt% ADS pellets were sintered at 1760 °C for 5.7 h for comparison purposes. The results show that the densification rate increases using the solid lubricant, but the shrinkage is lowered by 0.7% due to low homogenization. The average grain size was increased by about 35% during sintering. Based on our results and a literature review, a mechanism for grain growth by aluminum addition is proposed.
Nickel electrodeposition in LEU metal foil annular targets to produce Mo-99
2022 - IANELLI, RICARDO F.; SALIBA-SILVA, ADONIS M.; TAKARA, ERIKI M.; GARCIA NETO, JOSE; SOUZA, JOSE A.B.; CARVALHO, ELITA F.U. de; DURAZZO, MICHELANGELO
The most used production route of Mo-99 is through the fission of U-235 in irradiation targets that are irradiated in research reactors. The annular target is a promisor design since it can incorporate high U-235 quantities, thus increasing the production yield of Mo-99. This target type uses a foil of uranium metal enveloped by a thin nickel foil that acts as a diffusion barrier. The process of uranium enveloping with nickel foil is today done manually. This operation risks the nickel foil breaking up during target assembling. In the present work, we studied the nickel electrodeposition over uranium metal foil surfaces to replace nickel foils. A pre-forming procedure of the uranium metal foil by calendering was developed to facilitate the assembling operation. The electrodeposition was done over the uranium foil pre-conformed in a tubular shape. An automated apparatus for electrodeposition of nickel in uranium tubular-shaped foil was developed. The results showed that the high nickel adherence to uranium metal depends on the proper activation of the uranium surface. Among the activation processes studied, the mechanical activation showed good adhesion of the nickel layer, with a loss of only 0.16% of uranium mass. Homogeneous and regular 12 μm thickness electrodeposited layers over the uranium metal were obtained. This work showed that the process could be used in continuous production technology, such as the production of irradiation targets.
Manufacturing LEU-foil annular target in Brazil
2022 - DURAZZO, MICHELANGELO; SOUZA, JOSE A.B.; IANELLI, RICARDO F.; TAKARA, ERIKI M.; GARCIA NETO, JOSE S.; SALIBA-SILVA, ADONIS M.; CARVALHO, ELITA F.U. de
Molybdenum-99 is the most important isotope because its daughter isotope, technetium-99m, has been the most used medical radioisotope. The primary method used to produce Mo-99 derives from the fission of U-235 incorporated in so-called irradiation targets. Two routes are being developed to make Mo-99 by fissioning with low enriched uranium (LEU) fuel. The first adopts UAlx-Al dispersion plate targets. The second uses uranium metal foil annular targets. The significant advantage of uranium foil targets over UAlx-Al dispersion targets is the high density of uranium metal. This work presents the experience obtained in the development of the uranium metal annular target manufacturing steps. An innovative method to improve the procedure for assembling the uranium foil on the tubular target was presented. The experience attained will help the future production of Mo-99 in Brazil through the target irradiation in the Brazilian Multipurpose Reactor (RMB).