Rankine theory and Coulomb theory are not suitable for the calculation of wall pressure by bulk materials, so this paper studies the actual distribution and calculation methods for the wall pressure in squat silos. Ba...Rankine theory and Coulomb theory are not suitable for the calculation of wall pressure by bulk materials, so this paper studies the actual distribution and calculation methods for the wall pressure in squat silos. Based on the limits equilibrium theory, the force on unit width of wall exerted by bulk materials is obtained, and the distribution of wall pressure is obtained by accurate mathematical deduction. It is proved that the results are in good agreement with those of the full-sized silo experiment, whether the top of the stored bulk materials is a horizontal plane or a conical pile.展开更多
In order to study the dynamic action and physical effects of coal seams and gas, a simulation system for this dynamic action was developed and a physical model built in our laboratory. Using this newly built model, th...In order to study the dynamic action and physical effects of coal seams and gas, a simulation system for this dynamic action was developed and a physical model built in our laboratory. Using this newly built model, the volume of coal outbursts and the temperature during the outburst process were studied. The results show that： l） for coal seams with similar structure and com- ponents, two factors, i.e., gas pressure and ground stress affect the volume of coal outbursts, with gas pressure being the more im- portant of the two and 2） the changes in coal temperature, both its increase and decrease, are affected by ground stress and gas pressure, it is a process of change. Preliminary tests show that the system can simulate the dynamic interaction of coal and gas, which is helpful for studying the dynamic mechanism of solid-gas coupling of gas and coal.展开更多
The paper proposes a novel nano-patterning method called electrically induced nanostructuring, where an external electric field, insteadof the external mechanical pressure, is applied to generate an electrohydrody- na...The paper proposes a novel nano-patterning method called electrically induced nanostructuring, where an external electric field, insteadof the external mechanical pressure, is applied to generate an electrohydrody- namic force acting on the polymer-air interface to drive the polymer＇ s flow into the mold cavities. This electri- cally induced nanostrueturing method no longer requires a large mechanical pressure externally applied for actua- ting the polymer filling in the mold cavities, and has been used to successfully fabricate micro/nano pillar arrays of a high aspect ratio （up to 10）, which have been usually considered to be ＂difficult to fabricate＂ by conventional molding or nanoimprinting processes.展开更多
文摘Rankine theory and Coulomb theory are not suitable for the calculation of wall pressure by bulk materials, so this paper studies the actual distribution and calculation methods for the wall pressure in squat silos. Based on the limits equilibrium theory, the force on unit width of wall exerted by bulk materials is obtained, and the distribution of wall pressure is obtained by accurate mathematical deduction. It is proved that the results are in good agreement with those of the full-sized silo experiment, whether the top of the stored bulk materials is a horizontal plane or a conical pile.
文摘In order to study the dynamic action and physical effects of coal seams and gas, a simulation system for this dynamic action was developed and a physical model built in our laboratory. Using this newly built model, the volume of coal outbursts and the temperature during the outburst process were studied. The results show that： l） for coal seams with similar structure and com- ponents, two factors, i.e., gas pressure and ground stress affect the volume of coal outbursts, with gas pressure being the more im- portant of the two and 2） the changes in coal temperature, both its increase and decrease, are affected by ground stress and gas pressure, it is a process of change. Preliminary tests show that the system can simulate the dynamic interaction of coal and gas, which is helpful for studying the dynamic mechanism of solid-gas coupling of gas and coal.
基金Major Research Plan of NSFC on Nanomanufacturing(No.90923040)National Basic Research Program of China(No.2009CB724202)
文摘The paper proposes a novel nano-patterning method called electrically induced nanostructuring, where an external electric field, insteadof the external mechanical pressure, is applied to generate an electrohydrody- namic force acting on the polymer-air interface to drive the polymer＇ s flow into the mold cavities. This electri- cally induced nanostrueturing method no longer requires a large mechanical pressure externally applied for actua- ting the polymer filling in the mold cavities, and has been used to successfully fabricate micro/nano pillar arrays of a high aspect ratio （up to 10）, which have been usually considered to be ＂difficult to fabricate＂ by conventional molding or nanoimprinting processes.
