IPEN

URI Permanente desta comunidade

https://repositorio.ipen.br/handle/123456789/10

Navegar

Agora exibindo 1 - 20 de 44363

0.6W single-frequency Nd:YVOsub(4)/BiBsub(3)Osub(6) laser at 671nm
2009 - CAMARGO, FABIOLA; WILLETTE, THOMAS Z.; BADR, THOMAS; WETTER, NIKLAUS U.; ZONDY, JEAN J.
1.3 Watt Single-Frequency Nd:YLF/ppKTP red laser
2009 - CAMARGO, F.; ZANON-WILLETTE, T.; SARROUF, R.; BADR, T.; WETTER, N.U.; ZONDY, J.-J.
Using a temperature-tuned ppKTP crystal, a record 1.3 W single-frequency red laser at 661 nm is achieved from intra-cavity second-harmonic generation of a Nd:YLiF 4 ring laser oscillating on the pi-polarized transition (lambda~1321 nm).
1.75W 3um pulsed Er:YLF laser diode end pumped with side pumped MOPA
2007 - DEANA, A.M.; WETTER, N.U.
10000 years cement
2019 - FERREIRA, EDUARDO G.A.; MARUMO, JULIO T.; FRANCO, MARGARETH K.K.D.; YOKAICHIYA, FABIANO; VICENTE, ROBERTO
This review is focused on the long-term performance of cementitious materials in a repository for radioactive waste. During the last few years, the disposal of disused sealed radioactive sources (DSRS) in a borehole type repository has been studied by many countries. The borehole concept is particularly useful to dispose of spent nuclear fuel and DSRS. In boreholes for DSRS, cementitious materials are intended to be used as structural material, immobilization matrix and as backfill. The understanding of the performance of these materials is essential to ensure the safety of the facilities during their required lifetime, from centuries to many thousands of years, depending on the initial activity and half-life of the waste. This review approaches the behavior of the cement from the hydration and hardening to the long-term processes that can affect its durability. Three main causes of failure of repository-engineered barriers are recognized: a) the formation of a preferential pathway for the migration of the contained radionuclides to the biosphere; b) loss of resistance and cohesion of the structural cementitious material; and c) the increase in the corrosion processes of the metallic components of the structures that affect the overall containment of the facility.
100W continuous linearly polarized, high beam quality output from standard side-pumped Nd:YAG laser modules
2017 - BERECZKI, ALLAN; WETTER, NIKLAUS U.
Dynamically stable operation with joined stability zones of a linearly polarized resonator is shown for a laser containing two diode side-pumped Nd:YAG rods. The unpolarized resonator generated 115W of output. When polarized by a Brewster plate, it reached 100.5W of output power at a beam quality M2 < 2. Best measured beam quality was of 1.1 and 1.3 in the x and y directions respectively, with 76W of 95% polarized output. The output power achieved is, to our knowledge, the highest reported for continuous polarized, fundamental-mode lasers using standard side-pumped Nd:YAG modules.
108mAg activity concentration determination in low and medium level radioactive waste from Angra Nuclear Power Plant
2021 - ANGELINI, M.; SILVA, P.S.C.; R.JUNIOR, I.S.
111In-DTPA-octreotide: production and quality control
2006 - BARBOZA, M.F.; FUKUMORI, N.T.O.; HERRERIAS, R.; SOUZA, A.A.; PIRES, J.A.; CERQUEIRA FILHO, A.; COUTO, R.; CAMPOS, D.G.; ARAUJO, E.B.; MENGATTI, J.; LINA, E.N.
123(19)kW passively Q-switched Nd:YLF laser operating at 1053 'micorns'
2011 - DEANA, ALESSANDRO M.; WETTER, NIKLAUS U.; BALDOCHI, SONIA L.; RANIERI, IZILDA M.
1337 nm emission of a Nd3+-doped TZA glass random laser
2023 - DIPOLD, JESSICA; BORDON, CAMILA D.S.; MAGALHAES, EVELLYN S.; KASSAB, LUCIANA R.P.; JIMENEZ-VILLAR, ERNESTO; WETTER, NIKLAUS U.
Random lasers have been studied using many materials, but only a couple have used glass matrices. Here, we present a study of zinc tellurite and aluminum oxide doped with different percentages of neodymium oxide (4 wt.%, 8 wt.%, and 16 wt.%) and demonstrate for the first time random laser action at 1337 nm. Laser emission was verified and the laser pulse’s rise time and input–output power slope were obtained. A cavity composed of the sample’s pump surface and an effective mirror formed by a second, parallel layer at the gain-loss boundary was probably the main lasing mechanism of this random laser system. The reason for the absence of emission at 1064 nm is thought to be a measured temperature rise in the samples’ active volume.
153Sm-EDTMP, fase III: Producao rotineira
1996 - GASIGLIA, H.T.; BARBOZA, M.F.; MENGATTI, J.; HERRERIAS, R.; PEREIRA, M.S.; SILVA, C.P.G.
16 anos de resultados de determinação de radionuclídeos emissores gama na água da piscina do reator IEA-R1
2022 - MADUAR, MARCELO F.; ALENCAR, MARCOS M. de; TEIXEIRA, LUIZ F.L.; NISTI, MARCELO B.
A avaliação dos parâmetros técnicos na operação do Reator de Pesquisas IEA-R1, em particular as características físico-químicos da água da piscina do IEA-R1, é parte integrante das atividades coordenadas pelo CRPq (Centro do Reator de Pesquisas) do IPEN. O Serviço de Gestão de Radiometria Ambiental realiza desde meados de 2003 a análise rotineira por espectrometria gama em amostras da água da piscina do IEA-R1. Os radionuclídeos usualmente detectados são: Ag-110m, Co-58, Co-60, Cr-51, I-131, Mn-54, Na-24, Np-239, Te- 132, W-187 e Zn-65. Alguns nuclídeos são detectados raramente, como Cs-137, Ba-140/ La-140 e Ru-103. O radionuclídeo que apresenta regularmente a maior atividade é Na-24, com concentrações na faixa de 100 a 150 kBq/L, corrigida para o horário de desligamento do IEA-R1. Outros apresentam radioatividade da ordem de 102 a 103 Bq/L (Ag-110m, Co-58, Co-60, Cr-51 e W-187) e os restantes, poucos Bq/L. A principal conclusão, ao longo do tempo, é que o tempo de espera após o desligamento e coleta das amostras é o fator fundamental na definição de quais radionuclídeos são e quais não são passíveis de quantificação radiométrica. As medidas realizadas entre cinco e sete dias após o desligamento do reator fornecem um compromisso ótimo na detecção de nuclídeos de meia-vida inferior a um dia e limites de detecção aceitáveis para nuclídeos de meia-vida superior a dez dias.
177Lu-PSMA-617
2019 - BOAS, CRISTIAN W.V.; SILVA, JEFFERSON de J.; BENEDETTO, RAQUEL; MENGATTI, JAIR; ARAUJO, ELAINE B. de
Introduction: PSMA-617 radiolabeled with lutetium-177 has shown good results in compassionate studies around the world, and there is great interest in this kind of therapy in Brazil. The Nuclear and Research Institute (IPEN-CNEN) in São Paulo city, is a national radiopharmaceutical producer and the distribution of radiopharmaceuticals for therapy in a country of continental dimensions such as Brazil, becomes a challenge from the standpoint of guaranteeing the stability of the product. This work evaluated the scheduling of pilot batches for the production of 177Lu-PSMA-617 and studied the effect of dilution and freezing on the stability of mono-doses of the product. Materials and Methods: Radiolabeling of PSMA-617 (ABX, Germany) with lutetium-177 (JSC, Russia) was performed in heating block at 90 °C for 30 minutes, 37 GBq (1 Ci), 500 μg of peptide and sodium ascorbate (0,5 M pH 4,7) as buffer. At the end of the radiolabel, 0,5 mL of DTPA solution (4 mg/mL pH 4,5) was added and the product was diluted with an appropriate volume of saline solution 0,9%. The final product was filtrated in 0.22 membrane and the doses were fractionated (7,4 GBq calibrated for 24 hours in approximately 2,4 mL) and conditioned in appropriate lead chambers inside a dry ice bucket for transport simulation. The radiochemical purity (RP) was evaluated in a stability study at, 24 and 48 hours by TLC and HPLC. The radionuclidic purity, sterility and bacterial endotoxins were also evaluated. Results and discussion: The radiopharmaceutical was stable after 48 hours (99.47% TLC and 99.39% HPLC), and was approved in radionuclidic, sterility and endotoxins assays. The vials fractionated in mono-doses calibrated for 24 hours showed high stability through freezing and dilution, which allowed the transportation to the Cancer Hospital of Barretos, distant 420 km from the production center in São Paulo. All these mono-doses were administrated to the patients after 24 hours of the production. Also, these results denote that is possible to scale up this production until 74 GBq and be used in a clinical trial that is being planned. Conclusions: These carried out experiments demonstrated that it is possible to produce 177Lu-PSMA-617 for use in clinical trials in Brazil. Until now, four patients are under treatment (compassionate use). Also, these results demonstrate that it is still possible to increase production activity to 74 GBq, just like is normally done with 177Lu-DOTATATE.
18O+48Ti elastic and inelastic scattering at 275 MeV
2024 - BRISCHETTO, G.A.; SGOUROS, O.; CARBONE, D.; CAPPUZZELLO, F.; CAVALLARO, M.; LUBIAN, J.; DE GREGORIO, G.; AGODI, C.; CALVO, D.; CHAVEZ LOMELI, E.R.; CIRALDO, I.; DELAUNAY, F.; DJAPO, H.; EKE, C.; FINOCCHIARO, P.; FISICHELLA, M.; GARGANO, A.; GUAZZELLI, M.A.; HACISALIHOGLU, A.; LINARES, R.; MEDINA, N.H.; MORALLES, M.; OLIVEIRA, J.R.B.; PAKOU, A.; PANDOLA, L.; SOUKERAS, V.; SOULIOTIS, G.; SPATAFORA, A.; TORRESI, D.; YILDIRIM, A.; ZAGATTO, V.A.B.
Background: In recent years, the NUMEN project has highlighted that the systematic study of double charge exchange (DCE) nuclear reactions could provide precious information on the nuclear matrix elements of neutrinoless double β decay. To achieve this goal, a multichannel approach was adopted, where a plethora of different reaction channels is measured under the same experimental conditions and analyzed in a coherent framework. In this context, the initial (ISI) and final (FSI) state interactions are fundamental building blocks to investigate all the relevant direct nuclear reactions. To date, such building blocks are not sufficiently established for many of the projectile-target pairs of interest for NUMEN experiments. This is also the case of the O18+Ti48 system, which is relevant for the double β decay of the Ca48 nucleus into the Ti48 one. Purpose: This work aims at deducing the ISI to be used in the multichannel study of the O18+Ti48 collision at 275 MeV incident energy. To this purpose, the optical potential and the strength of the couplings between elastic and inelastic scattering channels are determined and characterized by comparison with new experimental data. Methods: Cross section angular distributions were measured for the elastic and low-lying inelastic scattering channels in a wide range of momentum transfer. Experimental data were compared to theoretical calculations performed in optical model (OM), distorted-wave Born approximation (DWBA), coupled channels (CC), and coupled channels equivalent polarization potential (CCEP) approaches. For all of them, the São Paulo double-folding potential was adopted as the optical potential. The comparison between the predictions of the OM/DWBA and CC frameworks allowed to evaluate the strength of the couplings to the inelastic channels which were explicitly taken into account. Within the CC formalism, different coupling schemes were compared to assess the contributions of the states included in the model space. A further test of our approach was carried out by analyzing the experimental data of the same system at 54 MeV incident energy. Results: The achieved energy resolution allowed to resolve the elastic scattering and the excitation of the 21+ state of the Ti48 nucleus. A broad structure, associated to the superposition of the inelastic transitions to the 21+ state of O18 and to three excited states of Ti48, was also observed. The OM and DWBA calculations are not able to reproduce the experimental elastic and inelastic angular distributions in the explored range of momentum transfer. A significant improvement in the description of the data is found by using the CC approach. In particular, when the 21+ and 31- collective states of projectile and target and their simultaneous excitations are included in the coupling scheme, a satisfactory agreement is achieved. The CCEP predictions describe reasonably well the elastic scattering data. Conclusions: Channel coupling effects have to be taken into account for a good description of the elastic and inelastic experimental angular distributions in the measured range of momentum transfer. The inclusion of such couplings in the ISI is envisaged for the analysis of all the direct nuclear reactions induced by the O18+Ti48 collision in this incident energy region.
18O+76Se elastic and inelastic scattering at 275 MeV
2021 - LA FAUCI, L.; SPATAFORA, A.; CAPPUZZELLO, F.; AGODI, C.; CARBONE, D.; CAVALLARO, M.; LUBIAN, J.; ACOSTA, L.; AMADOR-VALENZUELA, P.; BORELLO-LEWIN, T.; BRISCHETTO, G.A.; CALABRESE, S.; CALVO, D.; CAPIROSSI, V.; CHAVEZ LOMELI, E.R.; CIRALDO, I.; CUTULI, M.; DELAUNAY, F.; DJAPO, H.; EKE, C.; FINOCCHIARO, P.; FIRAT, S.; FISICHELLA, M.; FOTI, A.; GUAZZELLI, M.A.; HACISALIHOGLU, A.; IAZZI, F.; LINARES, R.; MA, J.; MEDINA, N.H.; MORALLES, M.; OLIVEIRA, J.R.B.; PAKOU, A.; PANDOLA, L.; PETRASCU, H.; PINNA, F.; RIES, P.C.; RUSSO, G.; SGOUROS, O.; SOLAKCI, S.O.; SOUKERAS, V.; SOULIOTIS, G.; TORRESI, D.; TUDISCO, S.; WANG, J.; YANG, Y.; YILDIRIN, A.; ZAGATTO, V.A.B.
Background: An accurate description of the initial and final state interactions in the 18O+76Se collision is demanded by the NUMEN project. The study of single and double charge exchange nuclear reactions is the main purpose for NUMEN, since these can be used as tools to provide experimentally driven information about nuclear matrix elements of interest in the context of neutrinoless double-β decay. To date, the details of the optical potentials and nuclear response to isospin operators for many of the projectile-target systems proposed for the NUMEN double charge exchange studies are poorly known. The 18O+76Se case, here under study, is particularly relevant due to its connection with the 76Ge neutrinoless double-β decay. Purpose: In this work the authors want to characterize the initial-state interaction for the 18O+76Se reactions at 275 MeV incident energy determining the optical potential and evaluating the effect of couplings with the inelastic scattering on the elastic channel. Methods: The angular distributions of differential cross section were measured in the angular region between 4◦ and 22◦ in the center-of-mass reference frame. The cross sections were compared with theoretical calculations, that adopt different optical potentials. Coupling effects on the elastic channel were determined into the coupled channels formalism. Results: The excitation energy spectrum of the colliding nuclei and the cross section angular distributions were measured with satisfactory energy resolution. The elastic scattering cross section is not well reproduced in the full angular range explored when the optical model approach is adopted. A good agreement is found using coupled channel calculations. The initial state interaction for the 18O+76Se nuclear reactions at 275 MeV is determined. Conclusions: Coupled channels effects are crucial to obtain a good description of the measured elastic and inelastic channels cross sections, even at large transferred momenta where the optical model approach fails in reproducing the experimental data. The role of channel coupling could be relevant also in the analysis of other open reaction channels in the same collision and should be accounted for in double charge exchange analyses as well.
18O-induced single-nucleon transfer reactions on 40Ca at 15.3A MeV within a multichannel analysis
2021 - CALABRESE, S.; CAVALLARO, M.; CARBONE, D.; CAPPUZZELLO, F.; AGODI, C.; BURRELLO, S.; DE GREGORIO, G.; FERREIRA, J.L.; GARGANO, A.; SGOUROS, O.; ACOSTA, L.; AMADOR-VALENZUELA, P.; BELLONE, J.I.; BORELLO-LEWIN, T.; BRISCHETTO, G.A.; CALVO, D.; CAPIROSSI, V.; CHAVEZ LOMELI, E.R.; CIRALDO, I.; COLONNA, M.; DELAUNAY, F.; DJAPO, H.; EKE, C.; FINOCCHIARO, P.; FIRAT, S.; FISICHELLA, M.; FOTI, A.; GUAZZELLI, M.A.; HACISALIHOGLU, A.; IAZZI, F.; LA FAUCI, L.; LAY, J.A.; LINARES, R.; LUBIAN, J.; MEDINA, N.H.; MORALLES, M.; OLIVEIRA, J.R.B.; PAKOU, A.; PANDOLA, L.; PETRASCU, H.; PINNA, F.; RUSSO, G.; SOLAKCI, S.O.; SOUKERAS, V.; SOULIOTIS, G.; SPATAFORA, A.; TORRESI, D.; TUDISCO, S.; YILDIRIN, A.; ZAGATTO, V.A.B.
Background: Nucleon transfer reactions are selective tools for nuclear physics investigations. The theoretical and computational limits affecting in the past their data analysis could be nowadays surmounted thanks to the advent of methods with refined approximations and constraints, even when heavy-ion collisions are considered. Purpose: Modern microscopic calculations of heavy-ion-induced transfer reactions combined with precise experimental data offer the chance for accurately testing different reaction models as well as the nuclear structure description of the involved nuclear states. Method: Single proton and neutron transfer reactions were measured with theMAGNEX magnetic spectrometer for the 18O+40Ca system at 15.3A MeV. Excitation energy spectra and angular differential cross section distributions were extracted. The experimental results are compared with theoretical calculations performed in distorted wave and coupled channel Born approximation. The use of a coupled channel equivalent polarization potential to effectively describe the coupling effects affecting the initial state interaction is also considered. Spectroscopic amplitudes derived from a large-scale shell model with appropriate interactions adapted for the involved nuclei are employed. Results: Our theoretical calculations are in good agreement with experimental data, without the need for any scaling factor, validating the adopted reaction and nuclear structure parameters. Moreover, under the present experimental conditions, a weak dependence of the obtained results on the choice of the reaction models was observed. Conclusions: The good agreement between experimental and theoretical results validates the reliability of the parameter sets entering the calculations. They are extracted from or tested in complementary analyses of other reaction channels under the same experimental conditions. Such a multichannel approach represents the best option to pursue a solid, comprehensive, and model-independent description of the single-nucleon transfer reactions. The successful description of the present one-nucleon transfer data is also propaedeutic to the accurate assessment, under the same theoretical description, of higher-order transfer processes, like the sequential nucleon transfer mechanisms which are in competition with the direct charge exchange reactions.
1D large signal time-domain code for TWT
2011 - LOPES, DANIEL T.; MOTTA, CLAUDIO C.
1kHz repetition rate, mode-controlled, passively Q-switched Nd:YLF laser operating at 1053 nm
2012 - DEANA, ALESSANDRO M.; SOUSA, EDUARDO C.; RANIERI, IZILDA M.; BALDOCHI, SONIA L.; WETTER, NIKLAUS U.
1W diode-pumped tunable Hosup(3+) Prsup(3+)-doped fluoride glass fibre laser
2011 - HUDSON, D.; MAGI, E.; GOMES, L.; JACKSON, S.D.
200 Gy sterilised Toxoplasma gondii tachyzoites maintain metabolic functions and mammalian cell invasion, eliciting cellular immunity and cytokine response similar to natural infection in mice
2002 - HIRAMOTO, R.M.; GALISTEO JUNIOR, A.J.; NASCIMENTO, N.; ANDRADE JUNIOR, H.F.
20Ne + 76Ge elastic and inelastic scattering at 306 MeV
2019 - SPATAFORA, A.; CAPPUZZELLO, F.; CARBONE, D.; CAVALLARO, M.; LAY, J.A.; ACOSTA, L.; AGODI, C.; BONANNO, D.; BONGIOVANNI, D.; BOZTOSUN, I.; BRISCHETTO, G.A.; BURRELLO, S.; CALABRESE, S.; CALVO, D.; LOMELI, E.R.C.; CIRALDO, I.; COLONNA, M.; DELAUNAY, F.; DESHMUKH, N.; FERREIRA, J.L.; FINOCCHIARO, P.; FISICHELLA, M.; FOTI, A.; GALLO, G.; HACISALIHOGLU, A.; IAZZI, F.; LANZALONE, G.; LENSKE, H.; LINARES, R.; PRESTI, D.L.; LUBIAN, J.; MORALLES, M.; MUOIO, A.; OLIVEIRA, J.R.B.; PAKOU, A.; PANDOLA, L.; PETRASCU, H.; PINNA, F.; REITO, S.; RUSSO, G.; SANTAGATI, G.; SGOUROS, O.; SOLAKCI, S.O.; SOUKERAS, V.; SOULIOTIS, G.; TORRESI, D.; TUDISCO, S.; YILDIRIM, A.; ZAGATTO, V.A.B.
Background: Double charge exchange (DCE) nuclear reactions have recently attracted much interest as tools to provide experimentally driven information about nuclear matrix elements of interest in the context of neutrinoless double-β decay. In this framework, a good description of the reaction mechanism and a complete knowledge of the initial and final-state interactions are mandatory. Presently, not enough is known about the details of the optical potentials and nuclear response to isospin operators for many of the projectile-target systems proposed for future DCE studies. Among these, the 20Ne + 76Ge DCE reaction is particularly relevant due to its connection with 76Ge double-β decay. Purpose: We intend to characterize the initial-state interaction for the 20Ne + 76Ge reactions at 306 MeV bombarding energy and determine the optical potential and the role of the couplings between elastic channel and inelastic transitions to the first low-lying excited states. Methods: We determine the experimental elastic and inelastic scattering cross-section angular distributions, compare the theoretical predictions by adopting different models of optical potentials with the experimental data, and evaluate the coupling effect through the comparison of the distorted-wave Born approximation calculations with the coupled channels ones. Results: Optical models fail to describe the elastic angular distribution above the grazing angle (≈9.4◦). A correction in the geometry to effectively account for deformation of the involved nuclear systems improves the agreement up to about 14◦. Coupled channels effects are crucial to obtain good agreement at large angles in the elastic scattering cross section. Conclusions: The analysis of elastic and inelastic scattering data turned out to be a powerful tool to explore the initial and final-state interactions in heavy-ion nuclear reactions at high transferred momenta.

Navegar

Navegando IPEN por Título

Resultados por página

Opções de Ordenação