Earticle

This paper is intended to perform finite element analysis by and study the severity of the injury with and without helmet and the impact absorbing polystyrene with different shear modulus. The Impact absorption tests (drop tests) at three different points on head form were performed. The work also compares the deformations, velocities of the head form, accelerations that are obtained during the drop test according on the head form with and without the helmet and protective padding (liner) of different mechanical properties. The work also shows the necessity of different materials with energy absorbing.

The theoretical information of hadronic interactions according to the basis investigation of the multiple scattering process theory is described. Nowadays multi-particle reactions on the hadronic targets are attracting a great attention. To survey strong interaction of jet particles with quarks that are inside a hadrons1, we can use the estimate called high energy approximation2 theory that known very well in nuclear physics. This estimate describes collision and interactions of jet particles with quarks and scattering from multi-focus hadrons like diffraction phenomenon in optics. Glauber multiple scattering process theory may apply in analyzing elastic and inelastic collision of hadrons in a range of high energy levels. In elastic collision, scattering amplitude is equal to total ranges of multiple collisions inside the hadrons. It’s possible to express Glauber multiple scattering factors in a form of mathematics series. So that each elements shows the number of occurred scattering inside the hadrons. Determination of scattering amplitude by the high energy approximation depends on elected primary coming wave function of the shot particle and function of out coming wave from the target nucleus. Therefore it’s not so hard to determine scattering amplitude. The main purpose of this paper is to show how to determine mathematical formula for differential cross section of jet particles in high energy levels with a hadron in cluster model (qq, qq)3.

In recent year, main research direction in LED technology is improving lighting performance of white LED (CRI and lumen output). In this paper, effect of YAG:CE particle size on lighting performance of Multi-chip White LED (MCW-LEDs) is considered like an innovative method for improving their lighting performance. Main approaches of this work are: 1) using MCW-LEDs with high color temperature (CCT) near 8500 K, 2) investigating and demonstrating the effect of YAG:CE particle size on lighting performance of Multi-chip White LED with CCT 8500 K. Firstly, the phosphor layer mechanism of real MCW-LEDs with flat silicone coating is simulated by using LightTools 8.1.0 program. Then by varying YAG:CE particle size, ΔCCT, CRI and lumen output of MCW-LEDs were calculated and analyzed. The simulation and experimental results showed that ΔCCT, CRI and lumen output of MCW-LEDs of 8500 K MCW-LEDs are significantly influenced by varying YAG:CE particle size. These results can be a prospective ideal for future improving white LED manufacture.

The Thermal spraying techniques are coating processes in which melted materials are sprayed onto a surface and the feedstock is heated by electrical or chemical means. High velocity oxy-fuel (HVOF) spraying is seen as the pre-eminent process for deposition of such coatings. The coating that is formed is not homogenous and typically contains a certain degree of porosity, and, in the case of sprayed metals, the coating will contain oxides of the metal. This paper examines the effect of WC–Co coatings on the wear behaviour, WC were thermally sprayed by a high-velocity oxy-fuel (HVOF) system from WC–12% Co powder. Sliding wear resistance of this coating was calculated using pin-on-disk tribometer (ASTM G99-90). The morphologies of WC-Co coating were observed by X-ray diffraction (XRD), Energy dispersive analysis and Scanning electron microscope (SEM). Micro hardness is calculated by using Vickers Hardness test. And it was found that WC-Co coatings show better wear resistant properties.

Ultrasonic velocity(U), density(ρ) and viscosity(η) measurements have been taken in two ternary liquid mixtures Ethylene glycol + cyclohexanone + Isopropyl acetate and Ethylene glycol + cyclohexanone + Isobutyl acetate with fixed mole fraction (0.4) of cyclohexanone, at different temperatures with increasing mole fraction of ethylene glycol. The experimental data has been used to calculate the free volume, molar volume, internal pressure, enthalpy, Gibbs free energy, Molar sound velocity and their excess values. They have been analysed to discuss the nature and strength of intermolecular interactions in these mixtures. The compositional variation of excess parameters have been correlated using the Redlich-Kister equation.