Introduction: Recently, the use of nanoparticles has increased for many purpose in medicine. One of these is using the nano particles in shields structure to protect sensitive organs such as breast which placed inside the field of chest CT scan and receives high dose. The aim of this study was the use of nano Bi2O3 to making shield for protection breast in chest CT examination ...

transfer table is an essential stage between roughing and finishing rolling stands in a hot-strip rolling mill. high temperature and long time that strip is exposed to air at this stage cause a considerable heat loss that accounts for uneven temperature distribution, non-uniform surfaces, reduced product quality and increased production costs. using thermal shields on the transfer table is cons...

background: changes in body composition may be used for monitoring progression/ regression of a disease. prompt γ-rays in vivo neutron activation analysis (ivnaa) has been widely used for the measurement of body composition in recent years. objective: in this paper, we tried to improve the safety of ivnaa operator. methods: the most important factor for reducing the operator receiving dose is t...

Most of internal combustion engines have one or two heat shields that have been installed on the exhaust manifold to avoid the heat transfer to upper parts of the engine such as the valve cover. In some engines, this part fails due to the fracture and causes engine noise and other failures in the engine. In this paper, the failure of a heat shield due to vibrational loads of the engine has been...

background: lead-based radiation shields are widely used in radiology departments to protect both workers and patients from any unnecessary exposure to ionizing radiation. recently there has been a great deal of concern expressed about the toxicity of lead. human lead toxicity is well documented. in that light, production of environmentally-friendly lead-free radiation shields with less weight ...

Introduction: The geologic features “shield fields” and “shield plains” (or “shield terrain”) have been used by a number of Venus researchers and authors of Venus geologic quadrangle maps. However, there has been occasional confusion concerning the two terms and the geologic units they define. Stratigraphic interpretation may vary due to the identification of clusters of small shields as either...

Transfer table is an essential stage between roughing and finishing rolling stands in a hot-strip rolling mill. High temperature and long time that strip is exposed to air at this stage cause a considerable heat loss that accounts for uneven temperature distribution, non-uniform surfaces, reduced product quality and increased production costs. Using thermal shields on the transfer table is cons...