Numerical Studies on Laser Welded Top-Hat Column under Axial Collision Based on the Concept of Super-Folding Element

Extruded longitudinal double-skinned aluminium body plates with integrated stiffeners are recently used for manufacturing in automobile industry like front rails and railway carriages. These extrusions provide light and heavy rigid structures. However, since it is not feasible to produce large parts by extrusion, these plates need to be connected, mostly by welding techniques. The crashworthiness performance of laser welded columns is evaluated using finite element (FE) analysis. This is very important in automobiles, since more attention is being paid to crashworthiness of the structures in recent years. The analysis method is based on the Superfolding Element (SE) concept, which originates from experimentally observed folding patterns of crushed shell elements. The FE model is used to predict accurately the progressive axial collapse of the lased welded columns and impact strength is greatly improved by laser welding technique

Antimicrobial and free radical scavenging activity of Cassia auriculata L. flowers

The antimicrobial and free radical scavenging activity of various solvent extract of Cassia auriculata flowers were assessed. Among the different extracts tested, methanol and petroleum ether extracts showed significant antimicrobial and radical scavenging activities. The most susceptible microorganisms were found to be Pseudomonas aeruginosa and Candida albicans. These could be responsible for observed activity in the flower of the plant, thus justifying its traditional uses especially in the treatment of microbial infections. IJONAS Vol. 3 (1) 2007: pp. 39-4