Advanced Materials Research Vols. 955-959

Abstract: Two new kinds of modified isobutylene-isoprene rubber (IIR) oil absorbers were successfully prepared via freeze-thaw method. In order to further improve IIR oil-sorbents performance, graphite and nanosilica were chosen as modifiers. The cryogels were prepared cross-linking of IIR containing modifier in benzene at-5 °C, using sulfur monochloride as crosslinker. The modified IIR structures were characterized by using scanning electron microscopy (SEM) and contact angle analysis (CA). The results show that graphite-modified IIR exhibit much higher uptake capacity than silica-modified. The sorption capacity of the best graphite-modified sample reaches 19.68 g.g^-1 for crude oil, 19.98 g.g^-1 for diesel and 19.50 g.g^-1 for lubricating oil, respectively. The adsorbed liquids can be removed by centrifuging and the recovered materials could also be used more than 30 cycles. This study demonstrated graphite-modified IIR are more excellent and recommendable materials for oil removal.

Abstract: Using of the process of "double-reverse flotation " to the semi-weathered ore resources from Yunnan Dianchi areas. The first section, it using the anionic collector to floating and excluding dolomite impurities; The second section,it adopting cationic collector to floating the siliceous materialand and argillaceous gangue. In the "double reverse flotation technology", it mainly by adding a new phosphate inhibitor to enhance the efficiency on desilication and desmagnesiumtion; also using a new desiliconization agent to improve the desilication efficiency and liquidity bubble.In the end,it can obtain qualified concentrate.

Abstract: The aim of this study is to evaluate the effect of shear stress on detachment and nitrification process in a mixed-population biofilm. The biofilm was grown under constant flow condition with low C/N ratio. During the experiment, ammonium oxidation rate reached above 99%. Sloughing events happened mainly under constant hydrodynamic condition. Detachment experiment showed that it’s not possible to control the occurrence of sloughing events by controlling shear stress. Pyrosequencing analysis of the biofilm showed that Proteobacteria and Bacteroidetes were the two most abundant phyla, but detachment would influence the relative abundance of AOB and NOB in biofilm to affect the nitrification process.

Abstract: With the demand of the stem mustard premature bolting forecast in Fuling area, from the biology characteristics of stem mustard’s early bolting, the paper analyzes the two-season planting test data of stem mustard in 2011, and screens the significant meteorological factors that affecting the stem mustard premature bolting, which is average air temperature of the first 9-12 days after sowing, the maximum temperature and precipitation days in the stage of sowing - 3 leaf, and then establishes the prediction model of stem mustard premature bolting by Logistic equation. Finally, the planting test data in 2012 are used to test the model, which can better simulate the occurrences of stem mustard premature bolting, and forecast has good feasibility. Keyword: Stem mustard; Premature bolting; Two-season; Prediction

Abstract: A scalable and cycle process for 2,4-dibromopyrimidine is developed by bromination of 2,4-dichloropyrimidine using phosphorus tribromide. Compared with the literature reported before, the amount of bromination agent-phosphorus tribromide has been greatly reduced and purification of the product by recrystallization is realized. The total yield of 2,4-dibromopyrimidine can reach to 85.4%. The process is more suitable for scale-up production.

Abstract: Zhundong coal has a huge proved reserve and many excellent properties. However, the alkali metal content in Zhundong coal is apparently high, which can accelerate the deactivation of De-NO_x SCR catalysts. In the present study, the effect of alkali metal deposition on activity of SCR catalysts through solution impregnation method was experimentally investigated. The results indicate that alkali metal deposition on the catalyst surface significantly deactivates the capacity of SCR catalysts. NaOH presents the most intense poisonousness. The catalytic effect on NO reduction reduces with the increase of alkali metal content on catalyst surfaces. In addition, potassium establishes more obvious poisonousness on SCR catalyst than sodium. There is interaction effect between sodium and potassium on deactivating the SCR catalyst.

Abstract: Zhundong coal has a huge proved reserve and many excellent properties. However, the alkali metal content in Zhundong coal is distinctly high, which can accelerate the deactivation of De-NO_x SCR catalysts. Using solution impregnation method, the effect of operation conditions on activity of SCR catalysts before and after poisoned by sodium was experimentally investigated. The results show that the NO reduction ratio raises with the increase of NH₃/NO ratio. Longer residence time results in higher NO reduction ratio. Compared with catalyst poisoned by NaCl, residence time presents less influence on activity of fresh catalyst in 250-400 ^oC, which is beneficial for De-NO_x process. Both O₂ and NO concentration have no apparent influence on NO reduction ratio.

Abstract: Compost is widely used for treating urban garbage and sewage sludge. The enzyme activity is one of the important parameters of microbial quantity and its activity intensity change in the composting process, and all of the biochemical reactions during the composting process are carried out with the enzymes involving. The composting progress and the material change are directly reflected by the enzyme activity. In Zhengzhou Bagang sludge disposal plant, sludge was mixed with straw to compost together and with the technology of high temperature solid state aerobic slot for sludge treatment. This study was done to research the tendency of peroxide enzyme activity, cellulose enzyme activity, pH, conductivity, moisture content in the process of compost. The result showed that at the beginning of the compost, cellulase activity increased first and then decreased gradually and tended to be stable. The catalase activity was higher at the beginning of the compost and at the period of temperature raising it was stable basically, then decreases quickly and after that it maintain on the lower level. The moisture content declined gradually during the composting process, and in the period of high temperature there are more moisture loss. PH increased at first, and with the temperature raised to high the pH decreased gradually and tended to be stable. Conductivity increased first, then decreased gradually to steady.

Abstract: Paper industry produces large amounts of sludge with about 65wt% moisture content. Due to its complex composition, the charge of traditional disposal method is high and easy to bring about secondary pollution. In this paper, the influences of temperature, oxidation coefficient and residence time on the performance of supercritical water oxidation (SCWO) of paper mill sludge were investigated. The results show that SCWO can almost completely eliminate organics in sludge and obtain transparent liquid products meeting relative national standards at 550°C, 5min with an oxidation coefficient of 3.0. However, during this process, TN changes to NH₃-N, so NH₃-N in liquid products increases with operation parameters, indicating the recalcitrant nature of NH₃-N, and which needs further treatment.

Abstract: This research was mainly on morphology observation of syrphid common species including Episyrphus balteatus, Eristalis latréillè, Eupeodes osten, and Melanostoma schiner. Observations of four species of syrphid morphological characteristics in Shenyang were of the first radial cell area (R1), the third radial cell area (R3), the fifth radial cell area (R5), the second median cell area (M2), the first anal cell area (1A), spurious vein and wing length. The results showed that the first radial cells area, the third radial cells area, the fifth radial cell area, the second median cells area, the first cell area and wing length of M. schiner were the minimum, and spurious vein length was the maximum. The first radial cell area of E. latréillè was larger than that in other three species. The first radial cell area of E. latréillè was larger than that in other three species. The third radial cell area, the fifth radial cell area and the second median cell area of E. balteatus were larger than that in other three species. The wing length of E. osten was longer than that in other three species. Significance test showed that syrphid wings of the same individual from the four species had no significant differences.