Axial liquid dispersion was experimentally studied in liquid-solid and gas-liquid-solid magnetically stabilized beds using the ferromagnetic catalyst of SRNA-4 as the solid phase. The effects of operating factors and ...Axial liquid dispersion was experimentally studied in liquid-solid and gas-liquid-solid magnetically stabilized beds using the ferromagnetic catalyst of SRNA-4 as the solid phase. The effects of operating factors and fluid characters, such as superficial liquid velocity, superficial gas velocity, magnetic field intensity, liquid viscosity and surface tension, on axial dispersion coefficients of liquid were investigated. The dispersion coefficients increased with the increase of superficial liquid velocity and superficial gas velocity, and decreased with the increase of liquid viscosity, liquid surface tension and magnetic field intensity. A correlation equation of Peclet number was obtained for both liquid-solid and gas-liquid-solid magnetically stabilized bed.展开更多
The landslide disaster caused by the argillaceous interlayer not only destroys buildings,cultivated land,and roads but also seriously endangers human life and safety.This study concerns the mineral composition of sele...The landslide disaster caused by the argillaceous interlayer not only destroys buildings,cultivated land,and roads but also seriously endangers human life and safety.This study concerns the mineral composition of selected argillaceous interlayer and their strength characteristics.To study the mineral composition of argillaceous interlayers,8 kinds of samples in the southern Jiangsu region of China were analyzed utilizing X-ray diffraction(XRD).The repeated direct shear strength tests(RDST)were carried out on the undisturbed specimens of the argillaceous interlayer.The results show that the argillaceous interlayer with high content of kaolinite shows ductile failure mode,which means that there is no obvious residual strength in the shear process.The arrangement of mineral particles on the shear surface of the specimens after different shear displacements was observed under the scanning electron microscope(SEM).It was observed that mineral particles on the shear surface showed a more directional arrangement with the increase of shear displacement.Furthermore,the influence of shear direction on the argillaceous interlayer with completely oriented mineral particles was studied through numerical experiments with four shear strength mechanisms proposition proposed.The influence of the mineral arrangement on the action occasion and magnitude of dilatancy component of shear strength is clarified in the shear mechanism.展开更多
Density functional theory calculations and ab initio molecular dynamics simulations are performed to study the feasibility of using borophene, a newly synthesized two-dimensional sheet of boron, as an anode material f...Density functional theory calculations and ab initio molecular dynamics simulations are performed to study the feasibility of using borophene, a newly synthesized two-dimensional sheet of boron, as an anode material for sodium-ion and sodium-oxygen batteries. The theo- retical capacity of borophene is found to be as high as 1,218 mAh g-1 （Nao.sB）. More importantly, it is demonstrated that the sodium diffusion energy barrier along the valley direction is as low as 0.0019 eV, which corresponds to a diffusivity of more than a thousand times higher than that of conventional anode materials such as Na2Ti307 and Na3Sb. Hence, the use of borophene will revolutionize the rate capability of sodium-based batteries. Moreover, it is predicted that, during the sodiation process, the average open-circuit voltage is 0.53 V, which can effectively sup- press the formation of dendrites while maximizing the energy density. The metallic feature and structural integrity of borophene can be well preserved at different sodium concentrations, demonstrating good electronic conductivity and stable cyclability.展开更多
基金Supported by the National Natural Science Foundation of China （No.20206023） and SIN0PEC （No.X504029）.
文摘Axial liquid dispersion was experimentally studied in liquid-solid and gas-liquid-solid magnetically stabilized beds using the ferromagnetic catalyst of SRNA-4 as the solid phase. The effects of operating factors and fluid characters, such as superficial liquid velocity, superficial gas velocity, magnetic field intensity, liquid viscosity and surface tension, on axial dispersion coefficients of liquid were investigated. The dispersion coefficients increased with the increase of superficial liquid velocity and superficial gas velocity, and decreased with the increase of liquid viscosity, liquid surface tension and magnetic field intensity. A correlation equation of Peclet number was obtained for both liquid-solid and gas-liquid-solid magnetically stabilized bed.
基金Project(41672258) supported by the National Natural Science Foundation of ChinaProject(2018045) supported by the Land and Resources Science&Technology Project of Jiangsu Province,China。
文摘The landslide disaster caused by the argillaceous interlayer not only destroys buildings,cultivated land,and roads but also seriously endangers human life and safety.This study concerns the mineral composition of selected argillaceous interlayer and their strength characteristics.To study the mineral composition of argillaceous interlayers,8 kinds of samples in the southern Jiangsu region of China were analyzed utilizing X-ray diffraction(XRD).The repeated direct shear strength tests(RDST)were carried out on the undisturbed specimens of the argillaceous interlayer.The results show that the argillaceous interlayer with high content of kaolinite shows ductile failure mode,which means that there is no obvious residual strength in the shear process.The arrangement of mineral particles on the shear surface of the specimens after different shear displacements was observed under the scanning electron microscope(SEM).It was observed that mineral particles on the shear surface showed a more directional arrangement with the increase of shear displacement.Furthermore,the influence of shear direction on the argillaceous interlayer with completely oriented mineral particles was studied through numerical experiments with four shear strength mechanisms proposition proposed.The influence of the mineral arrangement on the action occasion and magnitude of dilatancy component of shear strength is clarified in the shear mechanism.
基金supported by a Grant from the Research Grants Council of the Hong Kong Special Administrative Region,China(16213414)
文摘Density functional theory calculations and ab initio molecular dynamics simulations are performed to study the feasibility of using borophene, a newly synthesized two-dimensional sheet of boron, as an anode material for sodium-ion and sodium-oxygen batteries. The theo- retical capacity of borophene is found to be as high as 1,218 mAh g-1 （Nao.sB）. More importantly, it is demonstrated that the sodium diffusion energy barrier along the valley direction is as low as 0.0019 eV, which corresponds to a diffusivity of more than a thousand times higher than that of conventional anode materials such as Na2Ti307 and Na3Sb. Hence, the use of borophene will revolutionize the rate capability of sodium-based batteries. Moreover, it is predicted that, during the sodiation process, the average open-circuit voltage is 0.53 V, which can effectively sup- press the formation of dendrites while maximizing the energy density. The metallic feature and structural integrity of borophene can be well preserved at different sodium concentrations, demonstrating good electronic conductivity and stable cyclability.
