The ion selectivity of nickel hexacyanoferrate thin film to alkali cations in ESIX (electrochemically switched ion exchange) processes was investigated using molecular dynamics(MD) techniques; water and cation (Na+ an...The ion selectivity of nickel hexacyanoferrate thin film to alkali cations in ESIX (electrochemically switched ion exchange) processes was investigated using molecular dynamics(MD) techniques; water and cation (Na+ and Cs+) intercalation, configuration, and dynamics in reduced nickel hexacyanoferrate structures with different cation combinations were studied and compared with the experimental results. In the simulations, water was represented by an extended simple point-charge(SPC/E) model, and all other atomic interactions were represented by a universal force field(UFF). The potential energies of various cations combination (Cs+ and Na+) in reduced i-NiHCF and 1 mol/L Cs/NaCl mixed solution were obtained. In most cases, the total potential energy of the solid is reduced when water is intercalated into the various reduced NiHCF structures. Combining the solid and the solution simulation results, it is shown that the solid composition of 3Cs+/1Na+ is the stablest structure form (NaCs3Ni4[Fe(CN)6]3) over a range of solution compositions.展开更多
A polystyrene（PS）/nanosilica organic-inorganic hybrid material was prepared from styrene monomer and commercial aqueous silica sol containing large amounts of Si-OH by means of emulsion polymerization. The nanosilic...A polystyrene（PS）/nanosilica organic-inorganic hybrid material was prepared from styrene monomer and commercial aqueous silica sol containing large amounts of Si-OH by means of emulsion polymerization. The nanosilica sol was modified by the addition of the reactive coupling agent methacrylexy propyltrimethoxysilane （ MPS）, and the resulting latex particles were protected by surfactants such as sodium dodecyl sulphonate（ SDS）, hydroxypropyl methyl cellulose （ HMPC）, and poly （vinylpyrrolidone） （PVP）. The effects of the type of surfactant, the amount of surfactant, and the coupling agent on the shape and stability of the resulting latex particles were investigated. The TEM observation indicates that among SDS, HMPC, and PVP, SDS is the best surfactant. When the content of SDS is 0. 5% and the amount of MPS is 7% in the system, the latex with obvious core-shell structure could be obtained. The average diameters of the monodispersed particles range from 182 to 278 nm, and the average number of silica beads for each composite are 1325 and 4409, respectively. The FrIR analysis shows that PS was chemically linked to silica through MPS. The thermal gravimetric analysis shows that when there is a higher silica content, the hybrid composites have a better heat resistance.展开更多
基金Project (20006011) supported by the National Natural Science Foundation of China Project (20021017) by the Natural Science Foundation of Shanxi Province Project (2004-24) by the Scholarship Council Foundation of Shanxi Province
文摘The ion selectivity of nickel hexacyanoferrate thin film to alkali cations in ESIX (electrochemically switched ion exchange) processes was investigated using molecular dynamics(MD) techniques; water and cation (Na+ and Cs+) intercalation, configuration, and dynamics in reduced nickel hexacyanoferrate structures with different cation combinations were studied and compared with the experimental results. In the simulations, water was represented by an extended simple point-charge(SPC/E) model, and all other atomic interactions were represented by a universal force field(UFF). The potential energies of various cations combination (Cs+ and Na+) in reduced i-NiHCF and 1 mol/L Cs/NaCl mixed solution were obtained. In most cases, the total potential energy of the solid is reduced when water is intercalated into the various reduced NiHCF structures. Combining the solid and the solution simulation results, it is shown that the solid composition of 3Cs+/1Na+ is the stablest structure form (NaCs3Ni4[Fe(CN)6]3) over a range of solution compositions.
基金Supported by the National Natural Science Foundation of China(No. 50373037)the Special Funds for Major State BasicResearch Projects ( No. 2005CB623802) Specialized Research Fund for the Doctoral Program of Higher Education ( No.20040335077).
文摘A polystyrene（PS）/nanosilica organic-inorganic hybrid material was prepared from styrene monomer and commercial aqueous silica sol containing large amounts of Si-OH by means of emulsion polymerization. The nanosilica sol was modified by the addition of the reactive coupling agent methacrylexy propyltrimethoxysilane （ MPS）, and the resulting latex particles were protected by surfactants such as sodium dodecyl sulphonate（ SDS）, hydroxypropyl methyl cellulose （ HMPC）, and poly （vinylpyrrolidone） （PVP）. The effects of the type of surfactant, the amount of surfactant, and the coupling agent on the shape and stability of the resulting latex particles were investigated. The TEM observation indicates that among SDS, HMPC, and PVP, SDS is the best surfactant. When the content of SDS is 0. 5% and the amount of MPS is 7% in the system, the latex with obvious core-shell structure could be obtained. The average diameters of the monodispersed particles range from 182 to 278 nm, and the average number of silica beads for each composite are 1325 and 4409, respectively. The FrIR analysis shows that PS was chemically linked to silica through MPS. The thermal gravimetric analysis shows that when there is a higher silica content, the hybrid composites have a better heat resistance.
