Calcium polyphosphate (CPP) bioceramic with different porosities were prepared by controlling the concentration of the pore-foaming agent. Effect of porosity (0%, 15%, 30%, 45% and 60%) on the microstructure, pores interconnection, dissolution behavior and compressive strength of CPP bioceramic were investigated. Scanning electron microscope (SEM) and capillarity test results indicated that CPP...

Construction waste in Our country has a good recycling system, can carry out the production of various recycled building materials. In order to understand availability red brick construction waste, effect content aggregate on physical properties and strength concrete is discussed explore whether containing suitable for application masonry blocks. The results show that there no significant corre...

Porosity has been frequently observed in solidified, deep penetration pulsed laser welds. Porosity is detrimental to weld quality. Our previous study shows that porosity formation in laser welding is associated with the weld pool dynamics, keyhole collapse, and solidification processes. The objective of this paper is to use mathematical models to systematically investigate the transport phenome...

Introduction: Most scientists now accept that impacts on the earth of large asteroids and comets have occurred in the past, and will, without intervention , occur again; with devastating affects on the earth and all living creatures. About ten years ago, researchers [1,2] and others studied a number of ways that an asteroid could be diverted from an impending collision with the earth by pushing...

Neutron diffraction analysis was employed to measure residual stresses near welds in used anhydrous ammonia nurse tanks. Tensile residual stresses contribute to stress corrosion cracking of nurse tanks, which can cause tanks to release toxic ammonia vapor. The analysis showed that tensile residual stresses were present in the tanks measured, and the magnitudes of these stresses approached the y...

Introduction: The role of radiotherapy as a part of cancer management increases every year around the world. Thus, Radiation protection in the design of radiotherapy rooms are of great importance.   Materials and Methods: In present study using Monte Carlo method, MCNPX code, fourteen types of developed high density concretes with densities ranging from 2.45 ...