Static effort of rock mass very rarely causes of rock burst in polish coal mines. Rock bursts with source in the seismic tremor within the roof rock layers are prevailing. A seismic tremor is an effect of rupture or s...Static effort of rock mass very rarely causes of rock burst in polish coal mines. Rock bursts with source in the seismic tremor within the roof rock layers are prevailing. A seismic tremor is an effect of rupture or sliding in roof layers above the exploited panel in coal seam, sometime in a distance from actual exploitation. Sliding, as a rule occurs in fault zone and tremors in it are expected, but monolithic layer rupture is very hard to predict. In a past few years a practice of analyzing state of deformation in high energy seismic tremors zones has been employed. It let gathering experience thanks to witch determination of dangerous shape of reformatted roof is possible. In the paper some typical forms of roof rocks deformations leading to seismic tremor occurrence will be presented. In general these are various types of multidirectional rock layers bending. Real examples of seismic events and rock bursts will be shown.展开更多
The method of numerical solving of nonlinear model problems of theory of a complex quasi-potential in doubly-connected nonlinear-layered curvilinear domains considering inverse influence function of flow on a conducti...The method of numerical solving of nonlinear model problems of theory of a complex quasi-potential in doubly-connected nonlinear-layered curvilinear domains considering inverse influence function of flow on a conductivity coefficient of medium was developed on the basis of synthesis of numerical methods of the quasi-conformal mappings and summary representations in conjunction with domain decomposition by method Schwartz. The proposed algorithm allows finding the potential of the quasiideals field, construction a motion grid (fluid-flow grid) simultaneously defining the flow lines that separate of sub-domains constancy of coefficient conductivity and identification the piecewise-constant values of coefficient conductivity, the local flows for the known measurements on boundary of domain.展开更多
The surface geometry, electronic structure, and magnetism of Eu@C60 monolayer absorbed on Ag(111) have been investigated within the framework of density functional theory. The Eu@C60 monolayer has been constructed on ...The surface geometry, electronic structure, and magnetism of Eu@C60 monolayer absorbed on Ag(111) have been investigated within the framework of density functional theory. The Eu@C60 monolayer has been constructed on Ag(111) substrate by one of the hexagon faces of C60 downward and its mirror plane face parallel to Ag(111). The Eu@C60 monolayer induces a recon- struction of the Ag(111) substrate and the perpendicular distance between the Eu@C60 and Ag(111) surface is 2.06 A, being shorter than that between C60 and Ag(lll) surface by 0.05A. There is no chemical bond formed between the Eu@C60 and Ag(111), and only 0.55e transferred from Ag(111) to Eu@C60. A large magnetic moment about 6.80/μB per unit cell is found for Eu@C60/Ag(111) system.展开更多
文摘Static effort of rock mass very rarely causes of rock burst in polish coal mines. Rock bursts with source in the seismic tremor within the roof rock layers are prevailing. A seismic tremor is an effect of rupture or sliding in roof layers above the exploited panel in coal seam, sometime in a distance from actual exploitation. Sliding, as a rule occurs in fault zone and tremors in it are expected, but monolithic layer rupture is very hard to predict. In a past few years a practice of analyzing state of deformation in high energy seismic tremors zones has been employed. It let gathering experience thanks to witch determination of dangerous shape of reformatted roof is possible. In the paper some typical forms of roof rocks deformations leading to seismic tremor occurrence will be presented. In general these are various types of multidirectional rock layers bending. Real examples of seismic events and rock bursts will be shown.
文摘The method of numerical solving of nonlinear model problems of theory of a complex quasi-potential in doubly-connected nonlinear-layered curvilinear domains considering inverse influence function of flow on a conductivity coefficient of medium was developed on the basis of synthesis of numerical methods of the quasi-conformal mappings and summary representations in conjunction with domain decomposition by method Schwartz. The proposed algorithm allows finding the potential of the quasiideals field, construction a motion grid (fluid-flow grid) simultaneously defining the flow lines that separate of sub-domains constancy of coefficient conductivity and identification the piecewise-constant values of coefficient conductivity, the local flows for the known measurements on boundary of domain.
基金supported by the National Natural Science Foundation of China (Grant Nos. 10874039 and 11147172)support from the National Basic Research Program of China (Grant No. 2011CB606401)
文摘The surface geometry, electronic structure, and magnetism of Eu@C60 monolayer absorbed on Ag(111) have been investigated within the framework of density functional theory. The Eu@C60 monolayer has been constructed on Ag(111) substrate by one of the hexagon faces of C60 downward and its mirror plane face parallel to Ag(111). The Eu@C60 monolayer induces a recon- struction of the Ag(111) substrate and the perpendicular distance between the Eu@C60 and Ag(111) surface is 2.06 A, being shorter than that between C60 and Ag(lll) surface by 0.05A. There is no chemical bond formed between the Eu@C60 and Ag(111), and only 0.55e transferred from Ag(111) to Eu@C60. A large magnetic moment about 6.80/μB per unit cell is found for Eu@C60/Ag(111) system.