45 research outputs found
Effect of the intermediate velocity emissions on the quasi-projectile properties for the Ar+Ni system at 95 A.MeV
The quasi-projectile (QP) properties are investigated in the Ar+Ni collisions
at 95 A.MeV taking into account the intermediate velocity emission. Indeed, in
this reaction, between 52 and 95 A.MeV bombarding energies, the number of
particles emitted in the intermediate velocity region is related to the overlap
volume between projectile and target. Mean transverse energies of these
particles are found particularly high. In this context, the mass of the QP
decreases linearly with the impact parameter from peripheral to central
collisions whereas its excitation energy increases up to 8 A.MeV. These results
are compared to previous analyses assuming a pure binary scenario
FamĂlia pĂłs-divĂłrcio: a visĂŁo dos filhos
O artigo apresenta resultados de pesquisa qualitativa realizada com jovens adultos - filhos de pais separados -, quando se procurou analisar como percebem as mudanças que ocorreram em suas vidas em decorrĂŞncia do rompimento conjugal dos pais, especialmente em relação Ă convivĂŞncia familiar. Com esse objetivo, foram realizadas 30 entrevistas individuais com pessoas das camadas mĂ©dias da população, residentes no Rio de Janeiro, na faixa etária de 21 a 29 anos, filhos de pais separados. Esperada por alguns entrevistados, inexplicável para outros, a separação dos pais trouxe desdobramentos vistos como desagradáveis por alguns filhos. Dentre essas repercussões, destaca-se o fato de serem colocados no centro das desavenças, o afastamento do pai que saiu de casa, a preocupação com o genitor com quem ficaram residindo e a dificuldade para aceitar novos relacionamentos dos pais. Pela impossibilidade de se generalizar as conseqĂĽĂŞncias do divĂłrcio para os membros da famĂlia, conclui-se que Ă© de grande importância a avaliação dos desdobramentos da separação conjugal de forma diferenciada no que diz respeito aos pais e aos filhos
Determination of the Pa(n,f) reaction cross section from 0,5 to 10 MeV neutron energy using the transfer reaction Th(He,p)Pa
The fission probability distributions of 232, 233, 234Pa and 231Th have been measured up to an excitation energy of 15 MeV, using the transfer reactions 232Th(3He, t)232Pa, 232Th(3He, d)233Pa, 232Th(3He, p)234Pa and 232Th(3He, 4He)231Th. From these measurements, the neutron induced fission cross sections of 231Pa, 233Pa and 230Th have been determined from the product of the fission probabilities of 232Pa, 233Pa and 231Th respectively with the calculated compound nucleus formation cross sections in the 231Pa+n, 233Pa+n and 230Th+n reactions. The validity of the applied method has been successfully tested with the existing neutron induced fission cross sections of 230Th and 231Pa. Special emphasis is put on the 233Pa(n, f) reaction which is of importance for thorium fueled nuclear reactors. Based on a statistical model analysis of the neutron induced fission cross section as a function of neutron energy, it has been possible to determine the barrier parameters of the 234Pa fissioning nucleus. Cross sections for the compound nucleus inelastic scatttering 233Pa(n, n′) and radiative capture 233Pa(n, γ) reactions have also been calculated and compared with recent evaluations