The novel high-fidelity CFD model for packed bed reactors is validated in terms of Nu regarding particle-to-fluid heat transfer. The model is developed to take into consideration the flow of heat, mass and momentum through and around the particles each shaped without geometrical simplification. In the present approach, cylindrical shaped solid geometries are used to bridge particles in or near ...

background: alpha particle irradiation from radon progeny is one of the major natural sources of effective dose in the public population. oncogenic transformation is a biological effectiveness of radon progeny alpha particle hits. the biological effects which has caused by exposure to radon, were the main result of a complex series of physical, chemical, biological and physiological interaction...

objective(s):   the production of nano-hydroxyapatite by two encapsulated bacterial strains was the goal of current research.  materials and methods:   serratia marcscens atcc 14756 and pseudomonas aeruginosa ptcc 1570 were used by two methods including encapsulated form in 2% (w/v) alginate sodium powder and inoculated form (10%) in nutrient broth medium containing alginate sodium blank beads....

Objective(s):   The production of nano-hydroxyapatite by two encapsulated bacterial strains was the goal of current research.  Materials and Methods:   Serratia marcscens ATCC 14756 and Pseudomonas aeruginosa PTCC 1570 were used by two methods including encapsulated form in 2% (w/v) alginate sodium powder and inoculated form (10%) in nutrient broth medium containing alginate sodium blank beads....

This paper concerns the Stokes flow of an incompressible viscous fluid past a swarm of porous nanocylindrical particles enclosing a solid cylindrical core with Kuwabara boundary condition. An aggregate of porous nanocylindrical particles is considered as a hydro-dynamically equivalent to a solid cylindrical core with concentric porous cylindrical shell. The Brinkman equation inside the porous c...

The directivities of the fields radiated by a variety of cylindrical and spherical active coated nano-particles, which are excited by their respective sources of illumination at optical frequencies, are investigated. Particular attention is devoted to the influence of the source location and optical gain constant on the directivities. While significant variations in the directivities are realiz...

A model for bifurcation regions of the human tracheo-bronchial tree was developed. Equations for the surfaces are given to enable calculations of doses from alpha-particles emitted in these regions. It has been found that a bifurcation region is well approximated by a quasi-ellipsoid. The absorbed fractions of alpha-particles emitted in bifurcation regions were calculated by the Monte Carlo met...

This research evaluated the efficiency of combined anaerobic-aerobic processes for the treatment of slaughterhouse wastewater. The anaerobic reactor consists of a 3.95 L Plexiglas column with 60 mm diameter and 140 cm height. The cylindrical particles of polyvinyl chloride with 2 mm diameter and 1250 kg m-3 density packed to 60 cm of column were used as biomass saving material. The d...

The hydrodynamic properties of cylindrical ~rodlike and discoidal! particles in dilute solution have been computed using the bead-shell model treatment. Previous results @Tirado and Garcı́a de la Torre, J. Chem. Phys. 71, 2581 ~1979!; 73, 1993 ~1980!# for rods with length-to-diameter ratio p .2 are now extended to short cylinders and disks down to p50.1. The intrinsic viscosity is obtained for r...