The floating photovoltaic membrane prototype developed by Ocean Sun was selected as a reference object,and a 1∶40 scale laboratory model was designed and produced to further explore the impact of inflow conditions on...The floating photovoltaic membrane prototype developed by Ocean Sun was selected as a reference object,and a 1∶40 scale laboratory model was designed and produced to further explore the impact of inflow conditions on the hydrodynamic properties of the membrane structure.By conducting free attenuation tests,results showed that the inflow has only a slight effect on the natural frequencies of the heave,pitch,and surge of the membrane structure.This finding shows that the dynamic properties of the membrane structure remain essentially stable under different inflow conditions.The results of further regular and irregular wave hydrodynamic experiments show that,compared with the control group,the response of the membrane structure under inflow conditions in terms of heave,pitch,surge,and heave acceleration motions is relatively gentle,whereas the response of the membrane structure to the mooring force is strong.Especially when the waves are irregular,the inflow conditions have a more significant impact on the membrane structure,which may lead to more complex response changes in the structure.Therefore,in the actual engineering design process,the impact of inflow conditions on the behavior of the membrane structure must be fully considered,and appropriate engineering measures must be taken to ensure the safety and stability of the structure.展开更多
To solve the problems concerning water entry of a structure, the RANS equations and volume of fluid (VOF) method are used. Combining the user-defined function (UDF) procedure with dynamic grids, the water impact o...To solve the problems concerning water entry of a structure, the RANS equations and volume of fluid (VOF) method are used. Combining the user-defined function (UDF) procedure with dynamic grids, the water impact on a structure in free fall is simulated, and the velocity, displacement and the pressure distribution on the structure are investigated. The results of the numerical simulation were compared with the experimental data, and solidly consistent results have been achieved, which validates the numerical model. Therefore, this method can be used to study the water impact problems of a structure.展开更多
This paper analyzes the impact of income distribution gap on consumption demand from a theoretical view,and draws the conclusion that there is an inverse relationship between income distribution gap and consumption de...This paper analyzes the impact of income distribution gap on consumption demand from a theoretical view,and draws the conclusion that there is an inverse relationship between income distribution gap and consumption demand.Then,the paper finds that the existing widening income distribution gap in China has a negative impact on consumption demand,but this is not the key factor for the insufficient consumption demand because of the low level of per capital income.At last,it suggests that governments should improve the income level of entire residents and adjust income distribution structure simultaneously.展开更多
The pore structure of the tight limestone in the Daanzhai Member of the Ziliujing Formation, Jurassic System, in central Sichuan Basin, China, is complex but essential to the exploration and development of tight oil. ...The pore structure of the tight limestone in the Daanzhai Member of the Ziliujing Formation, Jurassic System, in central Sichuan Basin, China, is complex but essential to the exploration and development of tight oil. The pore structure of the tight limestone is studied by using scanning electron microscopy (SEM), nitrogen adsorption, high-pressure mercury intrusion, and nuclear magnetic resonance (NMR). The experimental results suggest that the pores are mainly slit pores and mesopores and macropores contribute to the pore volume and specific surface. The displacement pressure, average pore size, and homogeneity coefficient correlate with porosity and permeability and can be used to evaluate the pore structure. The full pore-size distribution was obtained by combining nitrogen adsorption and high-pressure mercury intrusion. We find that the limestone mainly contains mesopores with diameter of 2-50 nm. The T2 distribution was converted into pore-size distribution, well matching the full pore-size distribution. The relation between T2 and pore size obeys a power law and the geometric mean of T2 correlates with the pore structure and can be used in the pore structure evaluation.展开更多
Used numerical simulation method to study the floor water-inrush mechanism in working face which was influenced by fault structure, and set up many kinds of models and performs numerical calculation by fully using lar...Used numerical simulation method to study the floor water-inrush mechanism in working face which was influenced by fault structure, and set up many kinds of models and performs numerical calculation by fully using large finite element soft-ANSYS and element birth-death method. The results show that the more high the underground water pressure, the more big the floor displacement and possibility of water-inrush; the floor which has fault structure is more prone to water-inrush than the floor which not has fault structure, the floor which has multi-groups cracks is more prone to water-inrush than the floor which has single-group cracks. The numerical simulation result forecasts the water-inrush in working face preferably.展开更多
In this paper, an econometric model for the aquatic products consumption of urban residents was established, aiming at investigating the different effects of seven factors (urban residents' annual disposable income,...In this paper, an econometric model for the aquatic products consumption of urban residents was established, aiming at investigating the different effects of seven factors (urban residents' annual disposable income, annual consumption quantity of pork and poultry and related byproducts, family structure, aging level, educational background, having meals out of home, and the number of retail chains stores) on the aquatic products consumption quantity of urban residents. The result of the model showed urban residents' annual disposable income and having meals out of home play the greatest effect on the consumption of aquatic products, followed by the number of retail chains stores; family structure plays a negative effect on the consumption of aquatic products. Also, the analysis shows not only the prices of the aquatic products as well as substitutes should be considered and also the quantity of the meals consumed by residents out of home and the number of retail chains stores should be used as important associated factors in studying the change trend of aquatic products consumption, and simultaneously the effect of family structure on the consumption quantity of aquatic products should be taken seriously, so that the aquatic products consumption of Chinese residents should be further promoted and also the aquatic products market can attain a development.展开更多
The structure of [Bmim]2CuCl4 ionic liquids (Bmim: 1-butyl-3-methylimidazolium) with different ratios of H2O and C2H5OH was investigated using X-ray absorption fine structure (XAFS) technique. In this study, XAFS...The structure of [Bmim]2CuCl4 ionic liquids (Bmim: 1-butyl-3-methylimidazolium) with different ratios of H2O and C2H5OH was investigated using X-ray absorption fine structure (XAFS) technique. In this study, XAFS was employed to directly probe the conformational variations of copper ions in [Bmim]2CuCl4 with the addition of either water or ethanol. XAFS analysis confirmed that the structure of ionic liquids gradually transformed from tetrahedral to octahedral configuration with the increase in ratio of H2O. Our results also showed that water molecules coordinated with the copper ions of [Bmim]2CuCl4, leading to the conformational change in ionic liquids. However, the XAFS spectra of [Bmim]zCuCIa/C2H5OH indicated no coordination of anhydrous ethanol with the copper ions of [Bmim]2CuC14. The structure of [Bmim]2CuCl4 ionic liquids is maintained as the tetrahedral configuration in presence of ethanol. Therefore, anhydrous ethanol causes little variation in the structure of ionic liquids and it is a good solvent for the dilution of ionic liquids.展开更多
基金The National Natural Science Foundation of China(No.52171274).
文摘The floating photovoltaic membrane prototype developed by Ocean Sun was selected as a reference object,and a 1∶40 scale laboratory model was designed and produced to further explore the impact of inflow conditions on the hydrodynamic properties of the membrane structure.By conducting free attenuation tests,results showed that the inflow has only a slight effect on the natural frequencies of the heave,pitch,and surge of the membrane structure.This finding shows that the dynamic properties of the membrane structure remain essentially stable under different inflow conditions.The results of further regular and irregular wave hydrodynamic experiments show that,compared with the control group,the response of the membrane structure under inflow conditions in terms of heave,pitch,surge,and heave acceleration motions is relatively gentle,whereas the response of the membrane structure to the mooring force is strong.Especially when the waves are irregular,the inflow conditions have a more significant impact on the membrane structure,which may lead to more complex response changes in the structure.Therefore,in the actual engineering design process,the impact of inflow conditions on the behavior of the membrane structure must be fully considered,and appropriate engineering measures must be taken to ensure the safety and stability of the structure.
基金Foundation item: Supported by the of China (11302056), China National Natural Science Foundation Postdoctoral Science Foundation (2013M540272), Heilongjiang Postdoctoral Fund (LBH-ZI3051), the Fundamental Research Funds for the Central Universities (HEUCF140116) and Research Fund of State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University (1309).
文摘To solve the problems concerning water entry of a structure, the RANS equations and volume of fluid (VOF) method are used. Combining the user-defined function (UDF) procedure with dynamic grids, the water impact on a structure in free fall is simulated, and the velocity, displacement and the pressure distribution on the structure are investigated. The results of the numerical simulation were compared with the experimental data, and solidly consistent results have been achieved, which validates the numerical model. Therefore, this method can be used to study the water impact problems of a structure.
文摘This paper analyzes the impact of income distribution gap on consumption demand from a theoretical view,and draws the conclusion that there is an inverse relationship between income distribution gap and consumption demand.Then,the paper finds that the existing widening income distribution gap in China has a negative impact on consumption demand,but this is not the key factor for the insufficient consumption demand because of the low level of per capital income.At last,it suggests that governments should improve the income level of entire residents and adjust income distribution structure simultaneously.
基金The work was supported by the National Natural Science Foundation of China (No. 41374144), the National Key Basic Research Program of China (973 Program) (No. 2014CB239201), and SINOPEC Key Laboratory of Geophysics.
文摘The pore structure of the tight limestone in the Daanzhai Member of the Ziliujing Formation, Jurassic System, in central Sichuan Basin, China, is complex but essential to the exploration and development of tight oil. The pore structure of the tight limestone is studied by using scanning electron microscopy (SEM), nitrogen adsorption, high-pressure mercury intrusion, and nuclear magnetic resonance (NMR). The experimental results suggest that the pores are mainly slit pores and mesopores and macropores contribute to the pore volume and specific surface. The displacement pressure, average pore size, and homogeneity coefficient correlate with porosity and permeability and can be used to evaluate the pore structure. The full pore-size distribution was obtained by combining nitrogen adsorption and high-pressure mercury intrusion. We find that the limestone mainly contains mesopores with diameter of 2-50 nm. The T2 distribution was converted into pore-size distribution, well matching the full pore-size distribution. The relation between T2 and pore size obeys a power law and the geometric mean of T2 correlates with the pore structure and can be used in the pore structure evaluation.
文摘Used numerical simulation method to study the floor water-inrush mechanism in working face which was influenced by fault structure, and set up many kinds of models and performs numerical calculation by fully using large finite element soft-ANSYS and element birth-death method. The results show that the more high the underground water pressure, the more big the floor displacement and possibility of water-inrush; the floor which has fault structure is more prone to water-inrush than the floor which not has fault structure, the floor which has multi-groups cracks is more prone to water-inrush than the floor which has single-group cracks. The numerical simulation result forecasts the water-inrush in working face preferably.
文摘In this paper, an econometric model for the aquatic products consumption of urban residents was established, aiming at investigating the different effects of seven factors (urban residents' annual disposable income, annual consumption quantity of pork and poultry and related byproducts, family structure, aging level, educational background, having meals out of home, and the number of retail chains stores) on the aquatic products consumption quantity of urban residents. The result of the model showed urban residents' annual disposable income and having meals out of home play the greatest effect on the consumption of aquatic products, followed by the number of retail chains stores; family structure plays a negative effect on the consumption of aquatic products. Also, the analysis shows not only the prices of the aquatic products as well as substitutes should be considered and also the quantity of the meals consumed by residents out of home and the number of retail chains stores should be used as important associated factors in studying the change trend of aquatic products consumption, and simultaneously the effect of family structure on the consumption quantity of aquatic products should be taken seriously, so that the aquatic products consumption of Chinese residents should be further promoted and also the aquatic products market can attain a development.
基金supported by the National Natural Science Foundation of China(11079007,21306220)
文摘The structure of [Bmim]2CuCl4 ionic liquids (Bmim: 1-butyl-3-methylimidazolium) with different ratios of H2O and C2H5OH was investigated using X-ray absorption fine structure (XAFS) technique. In this study, XAFS was employed to directly probe the conformational variations of copper ions in [Bmim]2CuCl4 with the addition of either water or ethanol. XAFS analysis confirmed that the structure of ionic liquids gradually transformed from tetrahedral to octahedral configuration with the increase in ratio of H2O. Our results also showed that water molecules coordinated with the copper ions of [Bmim]2CuCl4, leading to the conformational change in ionic liquids. However, the XAFS spectra of [Bmim]zCuCIa/C2H5OH indicated no coordination of anhydrous ethanol with the copper ions of [Bmim]2CuC14. The structure of [Bmim]2CuCl4 ionic liquids is maintained as the tetrahedral configuration in presence of ethanol. Therefore, anhydrous ethanol causes little variation in the structure of ionic liquids and it is a good solvent for the dilution of ionic liquids.