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31.
The heating values of municipal solid waste generated in three towns with a population of less than 50 000, situated in Galicia (Spain), were measured with a static bomb calorimeter. Samples of raw refuse were burnt either as received or after sorting of the different combustible components. A study was made of samples from controlled and uncontrolled landfills. The calorific values were compared with those corresponding to a commercial residual derived fuel in order to study the possibility of using municipal solid waste as a source of recovered energy. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
32.
Production of xylanolytic enzymes by anAspergillus niger CCMI 850 isolate was investigated in batch cultures. The effect of the composition of a fermentation medium that did not include chemical inducers, on β-xylanase, β-xylosidase, α-l-arabinofuranosidase, and total cellulase activity was studied. With 4% xylan as the carbon source, about 65 U/mL of β-xylanase was obtained, whereas the total cellulase activity was undetectable, under the specified conditions. This β-xylanase activity represents the highest reported for a wild-type strain ofA. niger. The effect of pH and temperature on the activity of β-xylanase was studied. Partial characterization of the β-xylanase showed that with insoluble birchwood as substrate theK m andV max were 0.3 mM and 19 μmol/min, respectively. Aspects of using the crude β-xylanase preparation for applications in the pulp and paper industry were discussed.  相似文献   
33.
To obtain enriched methane content and improve the anaerobic digestion of a mixture of cattle dung, poultry waste, and cheese whey, the effect of various doses of Tegoprens: T-3012, T-3022, T-5842, T-5843, T-5851, T-5852 has been studied, in bench-scale digesters. Among them, Tegoprens 3022 showed more than a 45% increase in gas production with higher methane content.  相似文献   
34.
陈希慧  潘艳坤  黄初升  罗思琴  蔡民廷 《分子催化》2005,19(3):172-176,i001
研究了TiO2-SiO2混合氧化物对纸业废水中有色有机物的吸附与光催化降解效率.常温下.TiO2对纸业废水中有色有机物的吸附符合Freundlich模型,Qe=0.239Ce^0.791。TiO2-SiO2混合氧化物对纸业废水中有色有机物的吸附与光催化降解效率与催化剂样品的组成有关,光催化降解效率也与TiO2-SiO2表面总酸量有关.  相似文献   
35.
包覆型纳米铜-银双金属粉研究   总被引:21,自引:0,他引:21  
目前,导电胶或者电磁波屏蔽涂料用的导电性填料主要有三类,一是铜粉,二是银粉,三是铜-银双金属粉。铜粉具有来源广、价格低廉、导电性好等优点,但其抗氧化性能弱;银粉导电性与抗氧化性好,但其资源日益匮乏。大量的研究试图通过对铜粉进行表面改性来提高其性能。表面改性有两种方法,一是包膜处理,用SiO2溶胶处理铜粉,铜粉抗氧化性能提高,但其表面导电性能大大降低犤1犦;另一类方法是在铜粉表面覆盖一层导电性能与抗氧化性能均佳的银或金而制成双金属粉末犤2~5犦。制取高性能的铜-银双金属粉是该领域的研究重点。目前获得铜-银双金属粉的方…  相似文献   
36.
This paper describes a sensitive spectrophotometric method for the determination of mercury, based on the flotation of a mercury iodide-brilliant green complex with cyclohexane at pH 5 and dissolution of the complex in acetone. The absorbance of the complex is measured at 625 nm. Beer's law is obeyed from 4–500 g/l of mercury. The method is highly sensitive ( = 5.96 × 105 1 mol–1 cm–1) and selective, as it is free from interferences by almost all cations and anions in the presence of EDTA. Furthermore, a two-level orthogonal array design as a chemometric method has been used for optimization of the various parameters involved. The method has been successfully applied to paper industry effluents.  相似文献   
37.
The title compound N'-tert-butylaminocarbonyl-N-2-chlorophenoxyacetylthiou- rea has been synthesized for the first time. Complete assignments were achieved by IR, 1H NHR and single-crystal X-ray diffraction analyses. The inhibitory rate of the cellular growth of K562 cells (chronic myeloid 1eukemic cells) was measured using MTT [3-(4,5-dimethylthiazo-2-y1)-2,5-di- phenyltetra-zolium bromide] assay. The cell apoptosis was assessed by agarose gel electrophoresis to find that the title compound has antiproliferation and apoptosis inducing effects on K562 cells. In order to investigate the relationship between structure and activity of the target compound, we report its crystal structure and biological behavior in the present paper. Crystallographic data: C14H18- ClN3O3S, Mr = 343.82, orthorhombic, space group Pnma, a = 19.786(6), b = 6.789(2), c = 12.938(4) , V = 1738.0(9) 3, Z = 4, Dc = 1.314 g/cm3, F(000) = 720, μ(MoKα) = 0.354 mm-1, R = 0.0378 and wR = 0.0941. The molecule is a planar structure.  相似文献   
38.
王东君  徐岩 《分析化学》1993,21(7):775-778
本文研究了9种表面活性剂对钛铁试剂体系纸上荧光法中Tb~(3+)特征荧光的增敏作用,并探讨了钛铁试剂-溴化十六烷基三甲胺体系纸上荧光法测定Tb~(3+)的最佳条件,Tb~(3+)的检测限为0.7ng。应用本方法成功地测定了中稀土分离富集物中Tb_4O_7的含量。  相似文献   
39.
液膜法处理含氟废水   总被引:4,自引:0,他引:4  
曾平  王玉鑫 《应用化学》1993,10(5):87-88
为了防止含氟废水的污染,人们研究了多种除氟方法,液膜技术是一项新的分离工艺,它操作简单,试剂用量少,有机相可重复利用。本文利用伯胺作迁移载体处理高含量的含氟废水,分离效率较好。 伯胺N_(1923)(简写RNH_2)为流动载体,上胺N_(205)(上海石油化工厂)为表面活性剂,煤油为溶剂。将内相CaCl_2,溶液与油相(含N_(1923)、N_(205)和煤油)按一定体积比例混合,高速搅拌,制成W/O  相似文献   
40.
Anhydrites(II)- CaSO4 were prepared from two waste gypsums (PRECHEZA Perov, FOSFA Potorná). The samples of anhydrites(II) with sulphate activators were tested on spillage, beginning and the end of setting time, bending and pressure strength. Both sodium and potassium sulphates accelerated setting of anhydrite, more impressively that prepared from Potorná gypsum. The addition of Na2SO4 influenced the strength of this anhydrite very favourably. On the contrary K2SO4 influenced favourably the strength of Perov anhydrite. Results confirm the necessity to evaluate properties of such materials with respect to their origin.  相似文献   
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