the synthesis of nano- structured cobalt through a controlled chemical process followed by heat treating at various temperatures is studied. the product is characterized by icp, xrd, fesem , and tem, indicating that the as- synthesized particles have an amorphous structure with 1.76 for co/b ratio, an average size of 50 nm. the transformation of intermediate phases into single phase nano- cryst...

Automobile manufactures are persistently trying to develop comfort of passengers by improving different specification such as decrease of sound level in engine compartments. There is a main problem that the noise generated in air intake systems may be disgusting. Statistical energy analysis is a suitable method for acoustical- vibration analysis of structures in high frequency range. In this pa...

Energy consumption share in construction part and dependent industries is about 40 percent of total energy consuming in Iran which is significant compared to other industries such as transportation, agriculture and therefore is of important. As energy consumption reduction and material durability improvement leads to cost reduction from one hand and environment pollution reduction on the othe...

With the rapid development of social economy in China, contradiction between wide distribution abandoned goaf and shortage land for engineering construction is becoming increasingly prominent. The effective utilization coal mining subsidence areas has become an measure to alleviate poverty promote green transformation cities. key scientific prevention control surface residual deformation, which...

In longwall top coal caving (LTCC), the resource recovery ratio of working face is directly determined by ratio. An investigation evolution drawing characteristics and revealing parameters necessary when providing guidance for parameter selection improving Based on in-situ measurements size distribution caved blocks in Wangjialing mine, a finite difference method (FDM)–discrete element (DEM) co...