المؤلفون: Silva, F S, Martins, M M, Conti, C C, Leite, S P, Fonseca, E S, Patrão, K C S, Pereira, W W

المصدر: Radiation Protection Dosimetry; Aug2018, Vol. 180 Issue 1-4, p42-45, 4p

مصطلحات موضوعية: MANGANOUS sulfate, PLUTONIUM, BERYLLIUM, NEUTRON source spectra, THERMAL neutrons, PARTICLE tracks (Nuclear physics)

مستخلص: This study describes the use of a neutron irradiator system based on a plutonium-beryllium neutron source for MnSO4 solution activation for use to determine the MSB system efficiency. Computational simulations using Monte Carlo code were performed to establish the main characteristics of the irradiator system. Among the simulated geometries and volumes, semi-cylindrical shape with 84.5 cm³ of MnSO4 solution yielded the best option to be built. Activity measurements were performed with a high-pure germanium detector to validate the new irradiation system. Results showed an average efficiency and uncertainty of the experimental standard deviation of the mean: 5.742 × 10⁻⁴ ± 0.036 × 10⁻⁴ (coverage factor k = 1), for MSB system. Efficiency value obtained shows good correlation to other published methods (i.e. a relative difference of 0.07%). This alternative metrological method demonstrated the utility of neutron sources for the irradiation of solutions in metrology laboratories providing a cost-efficient alternative to nuclear reactors or particle accelerators. [ABSTRACT FROM AUTHOR]

: Copyright of Radiation Protection Dosimetry is the property of Oxford University Press / USA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

المؤلفون: Pereira, W W, Estrada, J J S, Patrão, K C S, Alves, C F E, Magalhães, L A G, Leite, S P

المصدر: Radiation Protection Dosimetry; Aug2018, Vol. 180 Issue 1-4, p29-32, 4p

مصطلحات موضوعية: NEUTRON sources, NEUTRON temperature, ANISOTROPY, CALIBRATION

الشركة/الكيان: INTERNATIONAL Bureau of Weights & Measures

مستخلص: The Laboratório de Ciências Radiológicas is developing an irradiator for neutron survey meters calibration. Part of this work is related to the characterization of the neutron source that will be used in the irradiator. Therefore, a source of ²⁴¹Am–Be(α,n) was characterized according to the following attributes: neutron energy distribution, anisotropy and emission rate. In order to make these values into high-level metrological references traceable by the Bureau International des Poids et Mesures, these measurements were taken at the Neutron Laboratory part of the Laboratório Nacional de Metrologia das Radiações Ionizantes. Results obtained for the source spectrum have strong adherence to the reference spectrum established by ISO 8529-1. The new laboratory for neutron calibration will allow calibration in an approximate ambient dose equivalent ranging 20–4500 μSv/h. [ABSTRACT FROM AUTHOR]

: Copyright of Radiation Protection Dosimetry is the property of Oxford University Press / USA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

المؤلفون: Tinoco, M, Cardoso, F, Dias, G, Pereira, T, Faria, B, Almeida, F, Leite, S, Lourenco, A

المصدر: European Heart Journal: Acute Cardiovascular Care; 2022 Supplement, Vol. 11, p1-1, 1p

المؤلفون: Tinoco, M, Cardoso, F, Dias, G, Pereira, T, Faria, B, Almeida, F, Leite, S, Lourenco, A

المصدر: European Heart Journal: Acute Cardiovascular Care; 2022 Supplement, Vol. 11, p1-1, 1p

المؤلفون: Tinoco, M, Dias, G, Cardoso, F, Pereira, T, Lima, B, Oliveira, L, Hafe, P Von, Azevedo, O, Leite, S, Lourenco, A

المصدر: European Heart Journal: Acute Cardiovascular Care; 2022 Supplement, Vol. 11, p1-1, 1p

المؤلفون: Magalhães, J., de Castro, F. Dias, Carvalho, P. Boal, Leite, S., Moreira, M.J., Cotter, J.

المصدر: Journal of Crohn's & Colitis; Feb2014 Supplement, Vol. 8, pS104-S105, 0p

المؤلفون: Magalhães, J., de Castro, F. Dias, Moreira, M.J., Leite, S., Cotter, J.

المصدر: Journal of Crohn's & Colitis; Feb2013 Supplement, Vol. 7, pS182-S182, 1p

المؤلفون: Magalhães, J., Rosa, B., Moreira, M.J., Barbosa, M., Rebelo, A., Leite, S., Cotter, J.

المصدر: Journal of Crohn's & Colitis; Feb2013 Supplement, Vol. 7, pS107-S107, 1p