On the basis of the information entropy and equilibrium degree of urban land-use spatial structure, the paper analyzes the characteristics and rules of urban land-use spatial structure changes in Wuhan in 1990s, in wh...On the basis of the information entropy and equilibrium degree of urban land-use spatial structure, the paper analyzes the characteristics and rules of urban land-use spatial structure changes in Wuhan in 1990s, in which the types of land-use are shrinking and urban land-use changes are disequilibria. With PCA and GRA employed, the driving forces have also been analyzed. The driving force of city welfare and social structure, the towing force of city industrial structure transition, and the pressing force of city construction and reconstruction are main momentum factors. Moreover, the latter forces are more significant.展开更多
Membrane potentials across hybrid charged mosaic membrane in organic solutions were measured. Equilibrium swelling degree （SD） and fixed charge density in both organic solutions and water were also determined. Ethyl...Membrane potentials across hybrid charged mosaic membrane in organic solutions were measured. Equilibrium swelling degree （SD） and fixed charge density in both organic solutions and water were also determined. Ethylene glycol, ethanol, n-propanol and glycerol were used as organic solutes; meanwhile 0.001mol-dm^-3 aqueous KCl solution was utilized as a strong electrolyte to measure the electrical difference. Equilibrium swelling degree indicated that it could be affected by the density of organic solutes; while it enhanced with the increasing density of these solutes. The measurement of fixed charge density showed that the membrane had the maximal absolute value in water among these solvents whether for cationic or anionic groups; the difference of dielectric constant between the water and the organic solutes might be responsible for these change trends. It was confirmed that membrane potentials increased with both the increasing concentration of the organic solutions and the elevated pH values. These results demonstrated that the characteristics of the hybrid charged mosaic membrane could be highly impacted by the properties of the organic solutes. A theoretical modal for charged membranes in ternary ion systems of weak electrolyte can be used to explain the above-mentioned phenomena.展开更多
基金Supported by Knowledge Innovation Program of Chinese Academy of Sciences(No.KZCX2-SW-415).
文摘On the basis of the information entropy and equilibrium degree of urban land-use spatial structure, the paper analyzes the characteristics and rules of urban land-use spatial structure changes in Wuhan in 1990s, in which the types of land-use are shrinking and urban land-use changes are disequilibria. With PCA and GRA employed, the driving forces have also been analyzed. The driving force of city welfare and social structure, the towing force of city industrial structure transition, and the pressing force of city construction and reconstruction are main momentum factors. Moreover, the latter forces are more significant.
基金Supported by the National Natural Science Foundation of China （No.20576130） and the National Basic Research Program of China （973 program, No.2003CB615700）, and the Innovation Fund for the Graduate Students of USTC （No. KD2005022）.
文摘Membrane potentials across hybrid charged mosaic membrane in organic solutions were measured. Equilibrium swelling degree （SD） and fixed charge density in both organic solutions and water were also determined. Ethylene glycol, ethanol, n-propanol and glycerol were used as organic solutes; meanwhile 0.001mol-dm^-3 aqueous KCl solution was utilized as a strong electrolyte to measure the electrical difference. Equilibrium swelling degree indicated that it could be affected by the density of organic solutes; while it enhanced with the increasing density of these solutes. The measurement of fixed charge density showed that the membrane had the maximal absolute value in water among these solvents whether for cationic or anionic groups; the difference of dielectric constant between the water and the organic solutes might be responsible for these change trends. It was confirmed that membrane potentials increased with both the increasing concentration of the organic solutions and the elevated pH values. These results demonstrated that the characteristics of the hybrid charged mosaic membrane could be highly impacted by the properties of the organic solutes. A theoretical modal for charged membranes in ternary ion systems of weak electrolyte can be used to explain the above-mentioned phenomena.
