Neutron sources employed in different applications in both medicine and industry. Due to the harmful effects of neutron particles on living organisms, radiation shields have played a vital role in radiation protection against neutrons. In recent decade, numerous investigations conducted on the design and fabrication of nanocomposites as more efficient shielding materials against fast and therma...

background: a boron neutron capture therapy (bnct) facility, based on a dt neutron generator, with the final goal to find out a potential, alternative, solution to existing bnct treatment facilities which are based on nuclear reactors is examined. materials and methods: with the aim of the mcnp4b monte carlo code different beam-shaping assembly (bsa) configurations were considered. lead was sel...

in this research, cobalt and nickel sulfide nanoparticles (nps) were grown on almcm-41 matrix by using ion exchange method. the prepared samples were irradiated by thermalized neutron that emitted from am-be source up to fluencies (7.9+e9n/cm2). after that, x-ray diffraction (xrd), uv-vis spectroscopy, fourier transform infrared (ftir), scanning electron microscopy (sem) and transmission electr...

Developing a better understanding of xenon transport through porous systems is critical to predicting how this gas will enter the atmosphere after a below ground nuclear weapons test. Radioxenon monitoring is a vital part of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) International Monitoring System. This work details the development of prompt gamma activation analysis for measuring the di...

We calculate the rate of hydrogen burning for neutron stars (NSs) with hydrogen atmospheres and an underlying reservoir of nuclei capable of proton capture. This burning occurs in the exponentially suppressed diffusive tail of H that extends to the hotter depths of the envelope where protons are rapidly captured. This process, which we call diffusive nuclear burning (DNB), can change the H abun...

We perform a systematic analysis of the density dependence of the nuclear symmetry energy within the microscopic Brueckner–Hartree–Fock (BHF) approach using the realistic Argonne V18 nucleon-nucleon potential plus a phenomenological three body force of Urbana type. Our results are compared thoroughly to those arising from several Skyrme and relativistic effective models. The values of the param...

We consider the development of Implicit-Explicit (IMEX) RungeKutta schemes for hyperbolic and kinetic equations in the diffusion limit. In such regime the system relaxes towards a parabolic diffusion equation and it is desirable to have a method that is able to capture the asymptotic behavior with an implicit treatment of limiting diffusive terms. To this goal we reformulate the problem by prop...

Molecular dynamics (MD) simulations were carried out to elucidate the dynamic behavior of water confined in poly(vinyl alcohol), PVA, hydrogels. Model topology is supported by experimental network parameters, and simulation results are compared to an incoherent quasielastic neutron scattering (QENS) investigation carried out on PVA hydrogels. From the QENS dynamic scattering law (part I), a ran...

2014 The translational diffusion of liquid cyclopropane was studied by quasielastic neutron scattering (Q.N.S.) and by N.M.R. spin-echo in the temperature range 155-297 K. The values of the self-diffusion coefficient derived from the two techniques was the same within experimental accuracy (D = 0.78 x 10-5 cm2 s-1 at 155 K, and D = 9.2 x 10-5 cm2 s-1 at 297 K). This shows that high-resolution Q...

By using the technique of electrostatic levitation, the Ni self-diffusion, density, and viscosity of liquid Zr(64)Ni(36) have been measured in situ with high precision and accuracy. The inverse of the viscosity, η, measured via the oscillating drop technique, and the self-diffusion coefficient D, obtained from quasielastic neutron scattering experiments, exhibit the same temperature dependence ...