Advanced Materials Research Vol. 531

Abstract: Two blcok copolymer PSt-b-PtBMA were synthesized by using ATRP method, in acid conditions, and further hydrolysis into amphiphilic copolymers PSt-b-PMAA; the PS-b-PMAA containing transition metal complex was obtained through PNPh-Re covacent-link to PS-b-PMAA chains, and the corresponding copolymers were charcterized by UV-vis and 1 H NMR.

Abstract: Mg(OH)2 (MH) nanoparticles were synthesized by hydration of the light-burned MgO at low temperature (70°C) with the additive of magnesium acetate. Mg(OH)2 nanoparticles have platelet-like structure and approximately 20-40 nm in thicknesses. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were applied to characterize the crystal phase, size distribution and morphology of the crystal particles. The effect mechanism of magnesium acetate was proposed

Abstract: Molybdenum disulfide/carbon (MoS2/C) submicrosphere was synthesized through a PVP-assisted hydrothermal reaction of sodium molybdate and thiourea (CS(NH2)2), The structure and morphology of MoS2 composites were characterized by X-ray powder diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM). The lithium intercalation/de-intercalation behavior of as-prepared MoS2 submicrosphere electrode was also investigated. It was found that the MoS2 submicrosphere electrode exhibited the best electrochemical performance, retaining a specific capacity of 575mAh/g after 100 cycles, with higher first charge capacity (1037 mAh/g), which was better than those of the MoS2 prepared without PVP

Abstract: In the present study, an orthogonal array design was adopted to investigate effects of operational parameters including aeration intensity, membrane configuration and fiber length on membrane fouling in a lab scale. Mean membrane permeability decrease rate over the operation time was used to evaluate membrane fouling rate (MFR). In a constant pressure filtration mode of 15kPa, fiber length and aeration intensity were found to have a negative influence on MFR，and membrane configuration also had an obvious influence on MFR. The three factors in influencing MFR is in the order of fiber length>module configuration>aeration intensity. The experiments results also showed that the mean specific permeability displayed a slightly rise in the range of 60-100cm and the modules of two permeate outlet attain the best mean specific permeability in all the modules. According to this work, it show that membrane module design have a significance on membrane optimization.

Abstract: Thermoelectric ceramic targets of Ca₃Co₄O₉ and Ca₃Co₂O₆ were prepared by the sol-gel method. The technology and mechanism of synthesizing the thermoelectric thin films of Ca₃Co₄O₉ and Ca₃Co₂O₆ were investigated. The thin films of Ca₃Co₄O₉ and Ca₃Co₂O₆ were grown on (0001)-oriented (c-cut) Al₂O₃ substrates by pulsed-laser deposition techniques (PLD). Ca₃Co₄O₉ thin films grown at substrate temperature of 700°C and 800 °C appear to be obviously c-axis-oriented. But the x-ray diffraction peak of Ca₃Co₂O₆ thin films was not confirmed. Ca₃Co₄O₉ thin films and Ca₃Co₂O₆ thin films exhibited Ca elements and Co elements volatilization at high temperatures.

Abstract: Domestic organic tubular membrane was used uncommonly in treating catering sewage. The material of PVDF (polyvinylidene fluoride) shows excellent performance in my research. And it also showed great antipollution capacity to oil and grease when COD, TN, SS, OIL, LAS of the effluent accorded with “Synthetically Draining Standard of Sewage”, GB8978~1996.

Abstract: Using the as-prepared SiO2 aerogels as carriers, SiO2 aerogel supported nano-TiO2 (TiO2/SiO2 aerogel) photocatalysts were prepared by sol-gel and adsorption loading process. The microstructure, morphology and properties of the obtained TiO2/SiO2 aerogel were studied by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and Brunauer-Emmett-Teller (BET) N2 adsorption-desorption analysis. The adsorption/photocatalytic degradation for Rhodamine B of TiO2/SiO2 aerogel composite photocatalysts was investigated. The results indicate that TiO2 sol concentration is the main factor influencing the microstructure and properties of TiO2/SiO2 aerogel composite photocatalysts. With the increasing of TiO2 sol concentration, the amount of loaded TiO2 increased, but the specific surface area, pore volume and pore size gradually decreased. The specific surface area, pore volume and pore diameter of TiO2/SiO2 aerogel photocatalysts after annealed at 550oC are 444.76～750.34 m2/g, 0.08～0.70 m3/g and 2.46～4.58nm, respectively. The TiO2/SiO2 aerogel prepared with 0.75 mol/L TiO2 sol concentration has best adsorption/photocatalytic degradation for Rhdamine B.

Abstract: This study reports the encapsulation yield (EY) of B. bifidum BB28 encapsulated in different sodium alginate concentrations and in different proportion of BB28 and sodium alginate.It was studied by enumeration of viable cells after depolymerization of the capsules in 9mL trisodium citrate, followed by using MRS agar at 37°C for 48 h. The concentrations of sodium alginate was 1.5%, 2.0%, 2.5% and 3.0%.The proportion of cell suspension and sodium alginate was 1:5,1:10,1:15 and 1:20. Results were as follows: The optimum concentration of sodium alginate concentrations was 2.5% and the optimum proportion of cell suspension and sodium alginate was 1:10.

Abstract: Hydroxycamptothecin (HCPT) loaded PLA nanoparticles were prepared by a facile dialysis method. Three main influential factors, PLA concentration, ratio of HCPT to PLA (wt/wt), dialysis bags with different molecule weight cutoff, were evaluated using an orthogonal design, gave the nanoparticles with an average diameter of approximately 226.8 nm and fine drug loading content (5.16%, w/w). The in vitro drug release studies exhibited a slow and prolonged release profile over 30 days. It is concluded that the new method to prepare HCPT-PLA nanoparticles resulted in improved formulation characteristics including small size, high drug loading capacity, and long sustained drug release.

Abstract: The basicity, water solubility, intrinsic viscosity and molecular weight of carboxymethyl chitosan (CM-chitosan) were investigated. The solution pH remained at about 9.2 at the concentration of higher than 2.0 g/L. The isoelectric point of CM-chitosan was about 4.5 of pH, and the solubility of CM-chitosan at the solution pH of 2.0 to 6.0 was lower than 5 g/L. The acetic acid could be replaced by hydrochloric acid as solvent for the viscosity-average molecular weight determination of chitosan. The intrinsic viscosity values of CM-chitosan have significant differences in acidic and alkaline conditions. The viscosity-average molecular weight of CM-chitosan was (3.8 ± 0.2) × 10⁵, consistent with that of product chitosan of blank test.