background: boron neutron capture therapy (bnct) is a very promising treatment for patients suffering gliobastoma multiforme, an aggressive type of brain cancer, where conventional radiation therapies fail. thermal neutrons are suitable for the direct treatment of cancers which are located at near-tissue-surface deep-seated tumors need harder, epithermal neutron energy spectra. materials and me...

Background: Several landmine detection methods, based on nuclear techniques, have been suggested during the recent years. Neutron energy moderation, neutron-induced gamma emission, neutron and gamma attenuation, and fast neutron backscattering are nuclear-based methods used for landmine detection. The aim of this study is to use backscattered neutron for landmine detection. Materials ...

Quasielastic neutron scattering experiments and molecular dynamics ~MD! simulations have been used to investigate molecular diffusive motion near the melting transition of monolayers of flexible rod-shaped molecules. The experiments were conducted on butane and hexane monolayers adsorbed on an exfoliated graphite substrate. For butane, quasielastic scattering broader than the experimental energ...

Background: The aim of this work was to establish how well gel dosimeters performed, as substitutes for brain tissue compared with standard phantom materials such as water, polymethyl-methacrylate (or PMMA), A150 plastic and TE- liquid phantom material for dosimetry of neutron beams in boron neutron capture therapy. Materials and Methods: Thermal neutron fluence, photon dose and epithermal neu...

Starting from the transport equation, a systematic homogenization theory and a self-consistent dohomogenization theory for fuel assemblies have been developed using a multiple-scales asymptotic expansion method. The resulting theory provides a framework for coarsemesh nodal diffusion calculations of light water reactors. The theoretical development is carried out through second order in a small...

Muon spin relaxation and powder neutron diffraction have been combined to study three lithium cobalt nitride battery materials. Neutron diffraction shows that these retain the P6/mmm space group of Li(3)N with Co located only on Li(1) sites. The lattice parameters vary smoothly with the degree of metal substitution, such that the [Li(2)N] layers expand while the layer separation contracts, as o...

In the dense and crowded environment of the cell cytoplasm, an individual protein feels the presence of and interacts with all surrounding proteins. While we expect this to strongly influence the short-time diffusion coefficient Ds of proteins on length scales comparable to the nearest-neighbor distance, this quantity is difficult to assess experimentally. We demonstrate that quantitative infor...

Molecular dynamics simulations have been used to determine the diffusion of water molecules as a function of their position in a fully hydrated freestanding 1,2-dimyristoyl-sn-glycero-3-phosphorylcholine (DMPC) bilayer membrane at 303 K and 1 atm. The diffusion rate of water in a ∼10 Å thick layer just outside the membrane surface is reduced on average by a factor of ∼2 relative to bulk. For wa...

A quasielastic neutron scattering experiment has revealed the dynamics of surface water in a high surface area zirconium oxide in the temperature range of 300-360 K. The characteristic times of the rotational (picoseconds) and translational (tens of picoseconds) components of diffusion motion are well separated. The rotational correlation time shows an Arrhenius-type behavior with an activation...

Background: Miniature neutron sources with high neutron flux have abundant applications in medicine, industry and researches. The most important general characteristic of miniature neutron sources is their diameter which is 3mm in average. In this research, we have surveyed and designed an Am-Be miniature neutron source fabrication. Materials and Methods: This investigation resulted in creation...