in advance longwall mining, the safety of mine network, production rate, and consequently, economic conditions of a mine are dependent on the stability conditions of gate roadways. the gate roadway stability is a function of two important factors: 1) characteristics of the excavation damaged zone (edz) above the gate roadway and 2) loading effect due to the caving zone (cz) above the longwall w...

the sources of groundwater pollution such as, industrial effluents, sewage and extensive farming have lead to agrochemical pollution. mathematical modeling helps to analyze the existing situation, allows forecasting, and to evaluate the effects of changes in the surrounding water quality. the present research has been focused mainly towards understanding the various processes affecting the tran...

in this paper energy bands and berry curvature of graphene was studied. desired hamiltonian regarding the next-nearest neighbors obtained by tight binding model. by using the second quantization approach, the transformation matrix is calculated and the hamiltonian of system is diagonalized. with this hamiltonian, the band structure and wave function can be calculated. by using calculated wave f...

the used activated carbon was derived from pine-cone and was used for the removal of acid black 1(ab1) and acid blue 113(ab113) dyes. a batch sorption study was carried out in order to obtain optimum isotherm model. the study showed the best fit of the adsorption isotherm data was obtained using the langmuir model for both dyes. the monolayer maximum saturation capacities of ab1 and ab113 dyes ...

investigations are carried out to evaluate the performance of a low heat rejection (lhr) diesel engine consisting of air gap insulated piston with 3-mm air gap, with superni (an alloy of nickel) crown and air gap insulated liner with superni insert with different operating conditions of crude jatropha oil with varied injection timing and injection pressure.  performance parameters of brake ther...

the experimental study and modeling of gravity drainage during water alternative gas injection, wag process, in carbonate rock for one of the iranian off-shore reservoir at lab-scale were carried out. the mechanism of gravity drainage during the wag process, and its contribution to the oil recovery in the fractured carbonate reservoirs were also studied. in the wag process alternatively gas is ...