Advanced Materials Research Vols. 194-196

Abstract: Porous nano-strontium titanate (PST) was successfully prepared by the reversed-phase suspension polymerization and sol-gel method using reversed-phase suspension droplets as the template, and characterized by XRD and SEM. The ability of the new adsorption to remove lead, cadmium, zinc, copper and nickel ions from water samples was assessed. The results showed that the sorbents were porous, perovskite strontium titanate, and the average particle diameter of crystalloid was 30 nm. The lead, cadmium, zinc, copper and nickel ions were quantitatively retained at pH 5-8; their adsorption capacities of PST for lead, cadmium, zinc, copper and nickel ions were 145.9 mg•g^-1, 4.3 mg•g^-1, 25.2 mg•g^-1, 19.6 mg•g^-1and 3.7 mg•g^-1, respectively. The adsorbent can be regenerated completely by elution with 0.5 mol•L^-1 HNO₃. The adsorbent has a promising prospect in removal or enriching of lead, cadmium, zinc, copper and nickel in water.

Abstract: ZnO nanoparticles have been fabricated with cation resins templates by thermal decomposition reaction. TEM and XRD showed the ZnO nanoparticles synthesized have an average diameter of 46.5 nm with sphere-shaped. One strong green-light emission peak at 530 nm was observed.

Abstract: The best is to read these instructions and follow the outline of this text. Thermo-sensitive hydrogels based on linear HPMC and cross-linked PNIPAAm were prepared by the semi-IPN technique. The interior morphology of hydrogels was investigated by fluorescent microscope. The hydrogels were characterized by Fourier transform infrared (FTIR). The thermo-sensitivity, equilibrium swelling rate and swelling dynamics of these hydrogels were investigated. The chemical compositions and structures of the semi-hydrogels were similar to each other, as measured by FTIR. The results indicated that the swelling ratio of the hydrogel decreased with increasing temperature. In pH 7.4 buffer solution (37°C ), when the weight ratio of HPMC to NIPAAm was 1/100, the swelling ratio was the maximum. In comparision with a conventional PNIPA hydrogel, the semi-IPN hydrogel synthesized with hydroxypropyl-methyl cellulose exhibits a much faster response rate to temperature changes. For example, PNI-H05 loses 87% water within 5min, whereas the conventional hydrogel loses only about 25% water within 5 min. and about 50% water within 50 min.

Abstract: The interesting finding is reported that unusual calcium carbonate (CaCO₃) microspherules had been synthesized by simply mixing calcium chloride and ammonium bicarbonate with the assistance of dihexadecyl phosphate (DHP, an anionic lipid). The experimental results indicate that as-prepared CaCO₃ microspherules with complex surface texture are predominantly vaterite with high stability. DHP plays a critical role in the formation of the well-defined CaCO₃ microspherules.

Abstract: Well-dispersed CeO2 nanoparticles were successfully prepared in a simple system composed of sodium bis (2-ethylhexyl) sulfosuccinate (AOT)- octane-water (W/O) microemulsion in this paper. The morphology and microstructure of the products were characterized by the laser particle size analyzer, Fourier transform infrared spectroscopy (FT-IR), X-ray diffractometer (XRD), differential scanning calorimeter (DSC) and transmission electron microscope (TEM). It was found that the CeO₂ nanoparticles obtained from this method have well-proportioned size distributions; the surfactant (AOT) molecule was adsorbed on the surface of CeO₂ nanoparticles precursor, which is favorable for the dispersion of CeO₂ nanoparticles; the CeO₂ nanoparticles calcined was a crystal of the cubic structure. In addition, the mechanism on the formation of the CeO₂ nanoparticles was also proposed in this paper.

Abstract: MoS₂ with rose-like morphology have been successfully synthesized using by an ionic liquid-directed hydrothermal synthesis. XRD results showed that the as-prepared MoS₂ directed by ionic liquid Brij56 have the good peaks. SEM images revealed that the MoS₂ nanoflowers had rose-like morphology composed of many stacked sheets. TEM images showed that MoS₂ nanoflowers have incompactly petal-like stacked structure. These results showed that ionic liquid Brij56 could effectively influence the morphology of MoS₂. Ionic liquid played a crucial role as a structure-directed reagent in the formation of MoS₂ nanoflowers and the possible growth mechanism of MoS₂ nanoflowers was also discussed.

Abstract: The effect of biology activity on liquid indicators (pH, SCOD, VSS ,SOP etc.) and solid indicators (PHA , hepatin, TP etc.) of phosphorus-rich waste sludge during the anaerobic digestion were studied in this paper. Sludge used in this study was obtained from a sewage treatment plant in which the A/O process was used. The results indicated that the hydrolyzing of waste sludge was promoted by the addition of bacterium inhibitor in the beginning of experiment. However, the presence of bacterium inhibitor was disadvantage to both hydrolyzed and biological release mechanism of phosphorus in anaerobic digestion system.

Abstract: A solvothermal method has been developed for the synthesis of Cd_1-xZn_xS (x = 0–1) nanorods from a class of easily obtained, air-stable single-source molecular precursors, cadmium zinc bis(N,N-diethyldithiocarbamates). The phase, morphology, size and optical property of the resultant products were characterized by X-ray diffraction, transmission electron microscopy and UV-vis absorption spectra.

Abstract: In this paper, leaching behavior of heavy metals from the class C fly ash (CFA)-based geopolymers were studied. The CFA-based geopolymers were prepared from CFA, flue gas desulfurization gypsum (FGDG), and water treatment residual (WTR). The extraction-leaching concentrations of heavy metals from CFA-based geopolymers were lower than their maximum concentration limits according to the U.S. environmental protection law. And the encapsulated and fixed ratios of heavy metals by the CFA-based geopolymers were 96.02~99.88 %. The dynamic real-time leaching concentration of Pb (II) were less than 1.1 µg / L, Cr (VI) less than 3.25 mg / L while Hg (II) less than 4.0 µg / L. Additionally, dynamic accumulated leaching concentrations were increased at the beginning of leaching process then kept stable. The leaching results indicated that the security of heavy metals in CFA-based geopolymer was safe.

Abstract: Effects of different bentonite clarificants on the main organic acids contents in wine were investigated during the clarification process. Citric acid (CA) concentration changed slightly during the first day with average elimination ratio (AER) of 0.57%, and tartaric acid (TA), malic acid (MA), lactic acid (LA) and succinic acid (SA) were varied with AER of 12.39%, 9.80%, 7.27% and 6.27%, respectively, while acetic acid (AA) has the biggest AER of 15.42%. The pH and titratable acidity were significantly dependent on the variation of CA and TA. The –OH group in organic acids could be combined with –Si-O or –AlO groups in bentonite surface by hydrogen bond, which could caused the decrease in concentration various organic acids.