In this paper,We give the forms of AR sequences of a tilted algebra with terms all belonging to x(A_T),or all belonging to y(A_T).The sink maps of a tilted algebra which end at the indecompos able projective modules a...In this paper,We give the forms of AR sequences of a tilted algebra with terms all belonging to x(A_T),or all belonging to y(A_T).The sink maps of a tilted algebra which end at the indecompos able projective modules and the source maps of starting at the indecomposable injective modules are also obtained.These results together with the connecting sequecnes given in [3] determine the AR quiver of the tilted algcbra,morever,this can be done directly from the AR quiver of the correspond ing hereditary algebra.展开更多
Fluid invasion through fractures is frequently observed in subsurface engineering. To elucidate the microkinetic behavior of fracture fluids, the microfracture structure of coal from the Surat Basin was reconstructed ...Fluid invasion through fractures is frequently observed in subsurface engineering. To elucidate the microkinetic behavior of fracture fluids, the microfracture structure of coal from the Surat Basin was reconstructed using a 3D morphometric system and stitching algorithm, then the transparent models characterizing the fracture structure were produced using microfluidics, and water invasion in the microfracture model was measured via visualization experiments under various conditions. High flow rate facilitated the invasion of the water phase into the closed channel, improving the efficiency of water invasion in the neutral wetting system. Wettability reversal changed the dominant channel for water invasion in the hydrophobic system. The invasion efficiency in closed and small aperture bypass channels was low.The reduction of effective seepage channels led to the fastest breakthrough time. Higher surface tension and interfacial curvature promoted the hysteresis effect. The reduction of effective seepage channels led to the fastest breakthrough time. The larger surface tension and interfacial curvature make the hysteresis effect more significant. These results will enable a better understanding of the rock-gas-liquid multiphase interaction mechanisms under unsaturated conditions of rocks.展开更多
Hydroxyapatite bioceramics is simulated by using finite element method （FEM）. The influences of porosity, hole shape, angle of crack and other parameters on the ceramics are analyzed. The results show that with the ...Hydroxyapatite bioceramics is simulated by using finite element method （FEM）. The influences of porosity, hole shape, angle of crack and other parameters on the ceramics are analyzed. The results show that with the increase of the angle between crack and horizontal direction, the stress intensity factor KⅠ decreases gradually, but stress intensity factor KⅡ increases at first and then it decreases. The value of KⅡ reaches maximum when the angle between crack and horizontal direction is 45°. KⅠ and KⅡ rise with the increase of porosity, and they are almost the same for the circular and hexagonal holes. For elliptical holes, KⅠ and KⅡ reach maximum when the long axis of ellipse is perpendicular to the loading direction and they reach minimum when the same axis is parallel to the loading direction. Moreover, with the increase of the angle between the long axis and loading direction, KⅠ and KⅡ increase gradually.展开更多
文摘In this paper,We give the forms of AR sequences of a tilted algebra with terms all belonging to x(A_T),or all belonging to y(A_T).The sink maps of a tilted algebra which end at the indecompos able projective modules and the source maps of starting at the indecomposable injective modules are also obtained.These results together with the connecting sequecnes given in [3] determine the AR quiver of the tilted algcbra,morever,this can be done directly from the AR quiver of the correspond ing hereditary algebra.
基金Projects(52174159, 52074169, 52174026, 51904167, 52004146) supported by the National Nature Science Foundation of ChinaProject(ZR2020QE102) supported by the Natural Science Foundation Youth Branch of Shandong Province,ChinaProject(SKLMRDPC21KF06) supported by the Open Fund for State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines,China。
文摘Fluid invasion through fractures is frequently observed in subsurface engineering. To elucidate the microkinetic behavior of fracture fluids, the microfracture structure of coal from the Surat Basin was reconstructed using a 3D morphometric system and stitching algorithm, then the transparent models characterizing the fracture structure were produced using microfluidics, and water invasion in the microfracture model was measured via visualization experiments under various conditions. High flow rate facilitated the invasion of the water phase into the closed channel, improving the efficiency of water invasion in the neutral wetting system. Wettability reversal changed the dominant channel for water invasion in the hydrophobic system. The invasion efficiency in closed and small aperture bypass channels was low.The reduction of effective seepage channels led to the fastest breakthrough time. Higher surface tension and interfacial curvature promoted the hysteresis effect. The reduction of effective seepage channels led to the fastest breakthrough time. The larger surface tension and interfacial curvature make the hysteresis effect more significant. These results will enable a better understanding of the rock-gas-liquid multiphase interaction mechanisms under unsaturated conditions of rocks.
基金Supported by National Natural Science Foundation of China (No.10772133 and No.11072172)Specialized Research Fund for the Doctoral Program of Higher Education of China (No. 20090032110006)
文摘Hydroxyapatite bioceramics is simulated by using finite element method （FEM）. The influences of porosity, hole shape, angle of crack and other parameters on the ceramics are analyzed. The results show that with the increase of the angle between crack and horizontal direction, the stress intensity factor KⅠ decreases gradually, but stress intensity factor KⅡ increases at first and then it decreases. The value of KⅡ reaches maximum when the angle between crack and horizontal direction is 45°. KⅠ and KⅡ rise with the increase of porosity, and they are almost the same for the circular and hexagonal holes. For elliptical holes, KⅠ and KⅡ reach maximum when the long axis of ellipse is perpendicular to the loading direction and they reach minimum when the same axis is parallel to the loading direction. Moreover, with the increase of the angle between the long axis and loading direction, KⅠ and KⅡ increase gradually.
