High strength and elastic biodegradable membranes are of great demand in modern technology. Similar membranes have been developed by irradiating different weight poly (vinyl alcohol) (PVA) – hydroxypropyl guar gum (HPG) blends and followed by combining with ex situ nanosilica. Polarized light microscopic (PLM) study indicates that electron beam irradiation produced crosslinks and develop...

In this study, Al/Gr composites with 5,10,15,20 weight percent of graphite were produced by in-situ powder metallurgy method. The produced powder mixtures were consolidated and sintered at optimum conditions. The resultant composites were solution treated at 495?C and aged at 170?C. The influence of graphite content on the bending strength of composites was studied. The distribution of graphite...

in this research, using pyrolysis of phenolic resin in the presence of silicon particles, the sic ceramic composite is formed. the samples were prepared by introducing 30, 35, 40, 45 and 50 wt% of si particles to the phenolic resin. the samples were cured at 180°c then carbonized at 1100°c. the final carbonized c/si composites are hot-pressed at 1500°c in inert atmosphere, which is more than th...

sound power is considered as an excellent measure for evaluating the efficiency of noise controls as well as for comparing noise sources in workrooms. this parameter can be determined by sound pressure or intensity based methods in real conditions of workrooms. this paper aims empirically to compare these in situ methods in relation to a typical industrial machine located in workroom in terms o...

in this work, a thermoplastic polyurethane elastomer (tpue) model based on polytetramethylene glycol, toluene diisocyanate and 1,4-butanediol was selected and synthesized. according to this model two types of polyurethane nanocomposites were prepared by in situ polymerization and melt intercalation procedures. the organo-modified nanoclay was used in nanocomposites samples in 0.4 weight percent...

bis(2-r-ind)zrcl2 (r: h or phenyl) was supported on different types of silica by in situ impregnation method and used for ethylene polymerization. in this method, the step of catalyst loading on support was eliminated and common alkyl aluminum (triisobutylaluminum, tiba) cocatalyst was used instead of expensive methyl aluminiumoxane (mao) cocatalyst in the polymerization. the effect of surface ...

Structural health monitoring (SHM) is important for reducing maintenance costs while increasing safety and reliability. Traditionally, structural integrity tests required attachment of sensors to the material surface. This is often a burdensome and time-consuming task, especially considering the size and magnitude of the surfaces measured (such as aircraft, bridges, structural supports, etc.). ...