We present nuclear spin-rotation constants, absolute nuclear magnetic resonance (NMR) shielding constants, and shielding spans of all the nuclei in (175)LuX and (197)AuX (X = (19)F, (35)Cl, (79)Br, (127)I), calculated using coupled-cluster singles-and-doubles with a perturbative triples (CCSD(T)) correction theory, four-component relativistic density functional theory (relativistic DFT), and no...

This paper demonstrates that the addition of chemical agents and carbon fibers to cement can greatly enhance the shielding effectiveness of the concrete. In addition to improving the shielding effectiveness, carbon fibers and chemical agents enhance the tensile and flexural strengths significant ly. As both carbon fibers and steel fibers are electrically conductive, both can be added to cement ...

Shielding prevents coupling of undesired radiated electromagnetic energy into equipment otherwise susceptible to it. In view of this, some studies on shielding effectiveness of different shields against angle of incidence with conductors and conductive polymers using plane-wave theory are carried out in this paper. The plane wave shielding effectiveness of new combination of these materials is ...

Radiation shielding analysis and design calculations were performed for remote maintenance cells of the proposed National Spallation Neutron Source (NSNS) facility. In the analysis, a calculational strategy utilizing coupled high energy Monte Carlo calculations and multidimensional discrete ordinates calculations was implemented to perform an activation analysis and shielding assessment of the ...

Density functional theory methods(DFT) and natural bond orbital (NBO) analysis were used to investigate the effects of isomerism and side chain mutation at a microscopic level on the stability, binding energy and NMR/NQR tensors of structural isomers, L- methionylasparagine (Met-Asn) and L- asparagylmethionine (Asn-Met) in the gas phase. The results represented that the isomerism and side chain...

We report optimized design of multilayered electromagnetic shield using real coded genetic algorithm. It is observed that the shielding effectiveness in multilayer design is higher than single layered counterpart of equal thickness. An effort has been made to develop an alternative approach to achieve specific objective of identifying the design characteristics of each layer in the multilayered...

Radiation shielding requirements for fusion reactors present different problems than those for fission reactors and accelerators. Fusion devices, particularly tokamak reactors, are complicated by geometry constraints that complicate disposition of fully effective shielding. This paper reviews some of these shielding issues and suggested solutions for optimizing the machine and biological shield...

INTRODUCTION In radiation therapy centers across Iran, protection of normal tissues is usually accomplished by either Cerrobend or lead block shielding. In this study, the influence of these two shielding methods on central axis dose distribution of photon beam a Cobalt unit was investigated in clinical conditions. MATERIALS AND METHODS All measurements were performed for 60Co γ-ray beams and...

OBJECTIVES This study sought to determine the efficacy of patient pelvic lead shielding for the reduction of operator radiation exposure during cardiac catheterization via the radial access in comparison with the femoral access. BACKGROUND Cardiac catheterization via the radial access is associated with significantly increased radiation dose to the patient and the operator. Improvements in ra...