Abstract: A microbial flocculant (MBF) producing silicate bacteria MT5-2 was isolated from different sources of samples by silicate selected medium. Its chemical composition, optimal flocculation conditions，flocculation characteristics and primary application were studied in this paper. The results showed that the flocculant was an extracellular polysaccharide, and its flocculation activity was mainly distributed in the fermentation broth. The optimal flocculation conditions were as follows: for the 100 mL kaolin suspension, flocculant dosage was 4mL, metal cation dosage was 1% of ZnCl2 3mL, pH 7.5. The flocculation activity can reach 95% under this condition. Application results showed that flocculant MT5-2 had better flocculation activity in several common suspensions, such as kieselguhr, bentonite, soil, active carbon and starch, compared with polyacrylamide and inorganic salt.
Abstract: The solvent that is used to make the gel is water which is widely applied on the oil-field. The solvent is actually inject water. The chromes receipt which were already used on the oil- field is listed in the experiment, The research is that according to the inject water which come from Zhuangxi and Feiyan Beach oil field to make the gel, then to observe whether the polymer system gelatinize, which one is more practical and economical. The comparison was carried out in the experiment, the gel that is made of distilled water contrast with the get which is made of Zhuangxi and Feiyan Beach inject water, then observe the affecting factor of gelatinization, such as pH, temperature, drug style, concentration. According to the experiment, the intensity of the gel which is made of the Zhuangxi oil field inject water with the HPAM of Changan Group is the largest, however initial setting time is the shortest, the intensity of Feiyan Beach gel is smallest, initial setting time is the second .HPAM from Japan which is made up by water from Zhuangxi can be gelatinized at the initial pH, but The gel which is made of distilled water and Feiyan Beach can’t be gelatinized, the adjustment of the pH and the increasing concentration can make the polymer gel.
Abstract: Atmospheric particulate samples were collected during January, February, April and May 2012, separately. Twenty-one fatty acids and seven dicarboxylic acids were measured by GC-MS. The results show that average mass concentrations of fatty acids are 809.24ng/m³, 545.34ng/m³, 386.96ng/m³ and dicarboxylic acids are 215.14 ng/m³, 156.45 ng/m³, 111.43 ng/m³ in PM10, PM2.5, PM1, respectively. Fatty acids and dicarboxylic acids concentrate mainly in the PM1. C11-C24 of fatty acids exhibit a significant even carbon predominances, but dicarboxylic acids present no parity preponderance. In the fatty acids, the concentration of hexadecanoic acid is the highest with that of octadecanoic acid followed; Nonandioic acid is the highest in dicarboxylic acids. The results of source apportionments indicate that the fatty acids are mainly related with human activities. Coal burning for heating is the most important source in January and February, but its contribution decreases sharply in April and May for fatty acids; The main source of dicarboxylic acids is photochemical reactions.
Abstract: Long-term fertilization significantly inhibited the free-living N2-fixation rate (FNR) mainly because of the increased NO3–-N. DGGE profiles and redundancy analysis (RDA) plots clearly revealed that long-term fertilizations changed the community structures of N2-fixing bacteria (NFB) due to differences in N availability and pH. In addition, the differences in community composition were correlated with the changes in process rates for NFB (P < 0.05).
Abstract: Furfuryl alcohol is an important organic chemical material. The traditional catalysts of furfural hydrogenation to produce furfuryl alcohol contain Cr, which is harmful to people’s health and causes severe environmental pollution. Developing new highly active catalysts in furfuryl alcohol is of great practical significance. The progress of non-chrome catalysts for hydrogenation of furfural to produce furfuryl alcohol has been reviewed. Some environmental-friendly non-chrome catalysts, such as copper catalysts, CuO-CaO/SiO2 catalysts, Cu-Zn-Al catalysts, load Ni and ultra-fine Ni-B amorphous alloy catalysts, had been discussed and their preparations and structure characterizations were described. Some constructive strategies are presented for the research and applications of such catalysts.
Abstract: Taked an repaired completed slope - Vegetation-Growing Concrete Gunning (VGCG) slope for the experimental plot to measured indicators could evaluate the physical, chemical and biological properties.It showed that there were significantly difference in SBD, PH, SOM, AN. AP. AP and AK in different seasons, but no law. And there were significantly difference in soil enzyme activities except catalase in different seasons. Soil enzyme activities were highest in summer, lowest in winter except catalase. It showed that enzyme activitiy roses at first in the lower from spring to winter in one year. It proved that there were ruleless in seasonal change of the soil physical and chemical properties and there was a certain rule in seasonal change of the soil biological properties of the VGCG slope in one year.
Abstract: Ethyl cellulose (EC) was grafted with phthalic anhydride (PA) by esterification reaction without any catalyst in ethanol-methylbenzene mixture. The chemical structure and thermal stability of grafted copolymer (EC-g-PA) were analyzed by FT-IR and TGA, respectively, and compared with those of EC. The FT-IR results showed that EC has been grafted successfully with PA and the TGA results also show different thermal behavior between EC and EC-g-PA.
Abstract: A series of microcalorimetric experiments were performed to evaluate the As(III), Fe(II), P and their joint effects by analyzing the thermodynamic parameters, microbial growth rate constant k, total heat evolution QT, inhibitory ratio I and highest heat flow Pmax. They were obtained from power-time curves of the growth of P. fluorescens. The effect of mixed As(III), Fe(II) and P were moderate, compared with control, single As(III) or Fe(II). In addition, FT-IR spectra of dry P. fluorescens after the adsoption of As(III) and Fe(II) and their mixture showed that Fe influenced the C-H bonds of the functional groups on the cellwall, the As(III) caused litter effect.
Abstract: With C2H5OH as solvent and Ti(OBu)4 as precursor, the process for preparing TiO2 nanoparticles by sol-gel method was studied. The influence of different reaction conditions on gel time was studied in this study. Experiments show that nano-TiO2 can be well prepared by sol-gel method, the optimum volume ratio of Ti(OBu)4 to ethanol to acetic acid to water is 5:25:2:2, and that when the roasting temperature is 400°C,the crystalline phase is anatase; when the roasting temperature is 600°C, the crystalline phase is rutile.