Abstract The mechanisms of propellant gas chemical erosion on gun barrel materials are discussed creatively from a microscopic perspective molecular diffusion and intermolecular interaction. influence high-temperature high-pressure atoms the shallow surface microstructure material is theoretically analyzed using dynamics simulation method, which can be used as new idea for further study mechani...

In this paper, an arbitrary Lagrangian Eulerian (ALE) based numerical method has been presented for the numerical simulation of gas-particle two phase flow with moving boundaries. The main stages for the implementation of the algorithm have been discussed. The numerical results of cylindrical implosion and 2D dusty gas explosion have shown the effectiveness of the method.

OBJECTIVES To present the prevalence of gun ownership among batterers and describe their self-reported use of guns to threaten intimate partners. METHODS We used multivariate methods to analyze data from 8529 men enrolled in Massachusetts certified batterer intervention programs between 1999 and 2003. RESULTS Seven percent of the sample reported owning guns during the past 3 years. Recent g...

The SLC thermionic gun and electron source produce a beam of up to 15 x 10” ein a single S-band bunch. A 170 keV, 2 ns FWHM pulse out of the gun is compressed by means of two subharmonic buncher cavities followed by an S-band buncher and a standard SLAC accelerating section. Ceramic gaps in the beam pipe at the output of the gun allow a measure of the beam intensity and timing. A measurement at...

Available online 7 April 2011 Purposes: To determine if perceived risk of criminal victimization, and past criminal victimization experiences, increases the likelihood of a person owning a gun for self-protection, and to determine if defects in past research concerning the way gun ownership was measured had obscured such effects. Methods: We analyzed data on over 2,500 U.S. adults, using differ...

This study examines the relationship between gun availability and crime in a cross-national sample of cities. Data from the International Crime Victimization Survey are used to examine three competing hypotheses. The results of the limited information maximum least squares regression analyses suggest that gun availability influences rates of assault, gun assault, robbery, and gun robbery. These...

In cookware industry, interior spray coating process is an important process to protect the cookware product from the corrosion. In this process, the coating material “TEFLON” is used to spray to cover all the part’s surface. If a pot or pan is not too deep, one spray gun is enough to spray to cover all the interior surface. However, for the high side-wall pot, two spray guns must be used to sp...

Abstract To study the effect of a constant-pressure rear-spray low recoil weapon with two chambers on launch performance, based two-phase flow theory, valve-spring type firing process was studied numerically. Considering movement system, mathematical model combining gas and solid in front back chambers, projectile transient lateral rear nozzle is established. Using 30 mm chain gun as an example...