a gyroscope is a device for measuring or maintaining orientation , based on the principles of conservation of angular momentum . the device is a spinning wheel or disk whose axle is free to take any orientation. this orientation changes much less in response to a given external torque than it would without the large angular momentum associated with the gyroscope's high rate of spin. since exter...

in this study, a manganite sample with a nominal formula of la0.9sr0.1mno3 was prepared by the microwave assisted sol-gel method and annealing at various temperatures. the structural and magnetic properties of the samples were investigated by xrd, fesem and ac susceptometer, respectively. xrd analysis showed that the samples are a nearly single phase. fesem micrographs showed that by increasing...

in order to ensure the safety of parenterals, international pharmacopoeias and national standards have set up stringent guidelines and standards. particulate con- tamination is a potential health risk caused by intravenous injection of particles large enough to potentially clog the small arteries. particles could be produced through manufacturing and packaging or even dispensing of the pharmace...

the selective reduction of oximes with sodium borohydride (nabh4) in the presence of nano cu and charcoal was investigated. cu nanoparticles are widely used as catalysts; efficacious catalyst: copper and copper alloy nanometer feature high efficacy and selectivity, and can be used as catalyst in some reactions. we have shown that nabh4 in the presence of charcoal is an efficient protocol for th...

a novel nano – sized  manganese (ii) coordination polymer, [{mn(ncs)2(l)(h2o)2}(l)]n  , (1) (l- = 4,4'-bipyridine), have been synthesized by a sonochemical process and characterized by scanning electron microscopy (sem), x-ray diffraction (xrd), ir spectroscopy and elemental analysis.  direct calcination of the single crystals and nano-sized compound 1 at 400 0c under air atmosphere yields...

a considerable amount of energy is released in the form of shock wave from explosive charge detonation. shock wave energy is responsible for the creation of crushing and fracture zone around the blast hole. the rest of the shock wave energy is transferred to rock mass as ground vibration. ground vibration is conveyed to the adjacent structures by body and surface waves. geological structures li...

The classical N -body problem consisting of the interaction of N computational particles, is the key computational issue in a number of diverse fields of science including chemistry, fluid dynamics, and astrophysics. For particles interacting through long range potentials the direct evaluation of their mutual interaction nominally scales as OðN Þ. In order to reduce this computational cost a si...

in suspension polymerization, particle size distribution of polymer is the outcome of dynamic equilibrium between the break up and coalescence phenomena. the rates of break up and coalescence and consequently polymerization stability depend on several parameters, the most important of which are type and concentration of stabilizer. in this study, the effects of type and concentration of stabili...

in this study the effects of mesolites from moghueieh region and their particles size on performance, blood biochemical parameters and nutrient digestibility in broiler chickens were evaluated. the experiment was conducted on a completely randomized design with three treatments: without mesolite (control) and with fine particle mesolite (passed of 1 mm sieve and stay in 0.225 mm sieve) or large...

the growing interest in using natural fibers as reinforcing agents of polymer-based composites is mainly due to their advantages such as lower cost, lower density, ease of preparation, lower energy requirements for processing, biodegradability, wide availability and relative non-abrasiveness over traditional reinforcing fibers such as glass and carbon. in this study, wood-plastic composite (wpc...