Comparison Between Mass Attenuation Coefficient of Metals (Fe, Ag, Sn, Pt, Au, Pb) According to Their Atomic Number

The paper describes the X-ray attenuation in materials according to their atomic number, using six different materials from low atomic number to higher atomic number, Iron (Fe-26) as low atomic number, silver (Ag-47), tin (Sn-50), platinum (Pt-78), gold (Au-79) and lead (Pb-82) as high atomic number. Using the data were taken from the NIST Standard Reference Database 126. From the J. H. Hubbell and S. M. Seltzer work, a table of contents was used. Whereas The mass attenuation coefficient for the above six elements was taken and compared with each other.

Heat and Mass Transfer in a Differentially Heated Enclosure Filled With Supercritical Carbon Dioxide

Numerical simulations of heat and mass transfer in supercritical carbon dioxide are carried out for natural convection conditions in a differentially heated square enclosure. The two vertical walls are maintained at different temperatures while the two horizontal walls are insulated. For the mass transfer studies, a heated vertical naphthalene wall is considered. Properties of supercritical carbon dioxide are evaluated from the National Institute of Standards and Technology (NIST) Standard Reference Database 12. A correlation for the mean Nusselt number along the heated wall is obtained as a function of the heat transfer Rayleigh number (for a given Prandtl number). A correlation for the temporal Sherwood number along the naphthalene surface is obtained as a function of the mass transfer Rayleigh number, and Fourier number (for a given Schmidt number). The results are compared with result available in the literature.