JOSE HENRIQUE BUCHMANN
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Resumo IPEN-doc 24590 The use of environmental monitoring as a technique to identify isotopic enrichment activities2017 - SARKIS, J.E.S.; BUCHMAN, J.H.The use of environmental monitoring as a technique to identify activities related to the nuclear fuel cycle has been proposed, by international organizations, as an additional measure to the safeguards agreements in force. The elements specific for each kind of nuclear activity, or "nuclear signatures", inserted in the ecosystem by several transfer paths, can be intercepted with better or worse ability by different live organisms. Depending on the kind of signature of interest, the anthropogenic material identification and quantification require the choice of adequate biologic indicators and, mainly, the use of sophisticated techniques associated with elaborate sample treatments. This work demonstrates the technical viability of using pine needles as bioindicators of nuclear signatures associated with uranium enrichment activities. Additionally, it proposes the use of a technique widely diffused nowadays in the scientific community, the High Resolution Inductively Coupled Plasma Mass Spectrometer (HR-ICP-MS), to identify the signature corresponding to that kind of activities in the ecosystem. It can be also found a description of a methodology recently being applied in analytical chemistry, based on uncertainties estimates metrological concepts, used to calculate the uncertainties associated with the obtained measurement results. Nitric acid solutions with a concentration of 0.3 mol kg1, used to wash pine needles sampled near facilities that manipulate enriched uranium and containing only 0.1 g kg1 of uranium, exhibit a 235U:238U isotopic abundance ratio of 0.0092 ? 0.0002, while solutions originated from samples collected at places located more than 200 km far from activities related to the nuclear fuel cycle exhibit a value of 0.0074 ? 0.0002 for this abundance ratio. Similar results were obtained for sample solutions prepared by microwave assisted acid digestion and dry ashing process. The different values of 235U:238U isotopic abundance ratio obtained for samples collected in different places permit to confirm the presence of anthropogenic uranium and demonstrate the viability of using this technique and the methodology proposed in this work.Artigo IPEN-doc 07764 Programa de qualidade em um laboratorio analitico de ultra-tracos2000 - ULRICH, J.C.; BUCHMANN, J.H.; SARKIS, J.E.S.Artigo IPEN-doc 06589 Determinacao de metais em amostras de plantas atraves da tecnica de espectrometria de massas de alta resolucao com fonte de plasma induzido1999 - BUCHMANN, J.H.; SARKIS, J.E.S.; RODRIGUES, C.Artigo IPEN-doc 05081 Effect of differences in gas-dynamic behavior on the separation performance of ultracentrifuges connected in parallel1996 - PORTOGHESE, C.C.P.; BUCHMANN, J.H.Tese IPEN-doc 06861 Artigo IPEN-doc 07388 Determination of metals in plant samples by using a sector field inductively coupled plasma mass spectrometer2000 - BUCHMANN, J.H.; SARKIS, J.E.S.; RODRIGUES, C.Artigo IPEN-doc 16468 O conceito da incerteza aplicado aos processos de medição associados à preparação de um solução de referência para calibração2002 - BUCHMANN, JOSE H.; SARKIS, JORGE E. de S.Artigo IPEN-doc 09592 Environmental monitoring used to identify nuclear signatures2003 - BUCHMANN, J.H.; SARKIS, J.E.S.; RODRIGUES, C.Artigo IPEN-doc 11734 Environmental monitoring as an important tool for safeguards of nuclear material and nuclear forensics2006 - BUCHMANN, J.H.; SARKIS, J.E.S.; KAKAZU, M.H.; RODRIGUES, C.