Silver-tin oxide powders were synthesized by the hydrothermal method with Ag(NH_3)_2^+ solution and Na_2SnO_3 solution as raw materials and Na_2SO_3 as reductant. The precipitation conditions of Na2SnO3 solution and t...Silver-tin oxide powders were synthesized by the hydrothermal method with Ag(NH_3)_2^+ solution and Na_2SnO_3 solution as raw materials and Na_2SO_3 as reductant. The precipitation conditions of Na2SnO3 solution and the reduction conditions of Ag(NH_3)_2^+ were also investigated. The powders prepared were characterized by differential thermal analysis (DTA), X-ray diffraction analysis (XRD), scanning electron microscope (SEM) and energy spectrum analysis. The results show that pH value of the solution is a key parameter in the formation of Sn(OH)_4 precipitate and the reduction reaction of Ag(NH_3)_2^+ can release H+ ions, which results in synchronous precipitation of Sn(OH)_6~2- as Sn(OH)_4. The reduction of Ag(NH_3)_2^+ and precipitation of Na_2SnO_3 occur simultaneously and the coprecipitation of silver and tin oxide is reached by the hydrothermal method. The silver-tin oxide composite powders have mainly flake shape of about 0.3 μm in thickness and there exists homogeneous distribution of tin oxide and silver in the powder synthesized.展开更多
The magnetic gelatin-starch microspheres were prepared by modified emulsion cross-linking method with glutaraldehyde as the cross-linking agent. The structure, size distribution as well as morphology of magnetic micro...The magnetic gelatin-starch microspheres were prepared by modified emulsion cross-linking method with glutaraldehyde as the cross-linking agent. The structure, size distribution as well as morphology of magnetic microspheres were investigated by FT-IR spectrometer, dynamic laser scattering analyzer and scanning electron microscope, respectively. Bovine serum album(BSA)was chosen as model protein, and the adsorption processes were carried out under diversified conditions including BSA initial concentration, p H value, adsorption time and temperature to evaluate the performance of the magnetic microspheres. The average diameter of optimized spherical magnetic microspheres is 1.6 μm with excellent dispersivity, and the saturation magnetization is found to be equal to 1.056×10-2 A·m2. The adsorption isotherm of the BSA on the magnetic microspheres basically obeys the Langmuir model, with a maximum adsorption capacity of 120 mg/g and an adsorption equilibrium constant of 1.60 mL/mg.展开更多
基金Project(2001BA901A09)supported by the Key Program of Science and Technology Action of West China Development
文摘Silver-tin oxide powders were synthesized by the hydrothermal method with Ag(NH_3)_2^+ solution and Na_2SnO_3 solution as raw materials and Na_2SO_3 as reductant. The precipitation conditions of Na2SnO3 solution and the reduction conditions of Ag(NH_3)_2^+ were also investigated. The powders prepared were characterized by differential thermal analysis (DTA), X-ray diffraction analysis (XRD), scanning electron microscope (SEM) and energy spectrum analysis. The results show that pH value of the solution is a key parameter in the formation of Sn(OH)_4 precipitate and the reduction reaction of Ag(NH_3)_2^+ can release H+ ions, which results in synchronous precipitation of Sn(OH)_6~2- as Sn(OH)_4. The reduction of Ag(NH_3)_2^+ and precipitation of Na_2SnO_3 occur simultaneously and the coprecipitation of silver and tin oxide is reached by the hydrothermal method. The silver-tin oxide composite powders have mainly flake shape of about 0.3 μm in thickness and there exists homogeneous distribution of tin oxide and silver in the powder synthesized.
基金Project(GC201204)supported by the Open Fund of Guangdong Provincial Key Laboratory for the Green Chemicals,China
文摘The magnetic gelatin-starch microspheres were prepared by modified emulsion cross-linking method with glutaraldehyde as the cross-linking agent. The structure, size distribution as well as morphology of magnetic microspheres were investigated by FT-IR spectrometer, dynamic laser scattering analyzer and scanning electron microscope, respectively. Bovine serum album(BSA)was chosen as model protein, and the adsorption processes were carried out under diversified conditions including BSA initial concentration, p H value, adsorption time and temperature to evaluate the performance of the magnetic microspheres. The average diameter of optimized spherical magnetic microspheres is 1.6 μm with excellent dispersivity, and the saturation magnetization is found to be equal to 1.056×10-2 A·m2. The adsorption isotherm of the BSA on the magnetic microspheres basically obeys the Langmuir model, with a maximum adsorption capacity of 120 mg/g and an adsorption equilibrium constant of 1.60 mL/mg.
