68 research outputs found
Micro to nanostructural observations in neutron irradiated nuclear graphites PCEA and PCIB
The neutron irradiation-induced structural changes in nuclear grade graphites PCEA and PCIB were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), selected area electron diffraction (SAED) and electron energy loss spectroscopy (EELS). The graphite samples were irradiated at the Advanced Test Reactor at the Idaho National Laboratory. Received doses ranged from 1.5 to 6.8 displacements per atom and irradiation temperatures varied between 350 °C and 670 °C. XRD and Raman measurements provided evidence for irradiation induced crystallite fragmentation, with crystallite sizes reduced by 39–55%. Analysis of TEM images was used to quantify fringe length, tortuosity, and relative misorientation of planes, and indicated that neutron irradiation induced basal plane fragmentation and curvature. EELS was used to quantify the proportion of sp2 bonding and specimen density; a slight reduction in planar-sp2 content (due to the buckling basal planes and the introduction of non-six-membered rings) agreed with the observations from TEM
Balanço de compostos nitrogenados e estimativa das exigências de proteÃna de mantença de bovinos Nelore de três condições sexuais
Quantificação das Bactérias Sólido-Aderidas, Bactérias e Protozoários LÃquido-Associados do Rúmen de Bovinos Jovens Alimentados com Amiréia
Genetic divergence between genotypes of forage peanut in relation to agronomic and chemical traits
Suplemento múltiplo com ionóforos para novilhos em pasto: consumo, fermentação ruminal e degradabilidade in situ
Análise de crescimento e anatomia foliar da planta medicinal Ageratum conyzoides L. (Asteraceae) cultivada em diferentes substratos
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