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61.
DU Dongyun LI Dunshun YU Zhongshan Key Laboratory of Catalysis Material Science of Hubei Province College of Chemistry Material Science South-Central University for Nationalities Wuhan China Department of Chemistry Environmental Engineering Hubei Normal University Huangshi China Daye Non-ferrous Metals Company Limitted Huangshi China 《Chinese Journal of Reactive Polymers》2005,(Z1)
1. INTRODUCTION In recent years, water body eutrophication has become a serious problem. Eutrophication is caused mainly by growth of aquatic plants that are stimulated by dissolved nutrients such as phosphates. Concentrations of TN and TP over the level of cleaning-itself are major indicators for water body eutrophication [1,2]. The presence of trace amounts of phosphate (even less than one ppm) in treated waste water from municipalities and industries is often responsible for eutrophic… 相似文献
62.
The presence of trace phosphates in treated wastewater from municipalities and industries is often responsible for eutrophication problems in lakes, rivers, and other water bodies. In this paper,we report the removal of PO43- from water by using a pillared rectorite that we synthesized recently. The results show that cross-linking can significantly increase the adsorbing capacity of Na-rectorite for phosphates. The pH, the concentrations of F, NH4+ and COD are main factors, which affect the results for pillared rectorite to adsorb phosphates from water. The OH-, and F- ions decrease the capacity to adsorb phosphates, while the COD and NH4+ ions increase it. 相似文献
63.
CHEN Shuixia LUO Ying DONG Guohua ZENG Hanmin Materials Science Institute Zhongshan University Guangzhou China 《Chinese Journal of Reactive Polymers》2002,(2)
1. INTRODUCTION Nuclear explosion and thermal fission of U produce many kinds of nuclide. The major products consist of gaseous materials, in particular the noble gases Xe. In some types of nuclear reactor it is necessary to remove 135Xe from the cooling… 相似文献
64.
The comparison of Raman spectra of the chondrites (C, H, L, LL) has confirmed thatthere exist two types of meteorite carbon: one is the primary carbon present in carbonaceouschondrites (c) and the other is the secondary carbon contained in ordinary chondrites (H, L,LL). The parameter of order (I_G/I_D intensity ratio, similarly hereinafter) of primary car-bon tends to decrease with increasing petrologic type and it can reflect the temperature ofdust carrier at the time plasma gases in the early nebula were condensed to form primarycarbonaceous material and the hydrogen content in primary carbonaceous material. This kindof primary carbonaceous material maybe has not experienced late stage thermometamorphismwithin the parent body of chondrites, indicating that the carbonaceous chondrites wereformed and retained in the low temperature region of the solar system. The parameter oforder of the secondary carbon tends to increase with increasing petrologic type and it can re-flect the degree of graphitization o 相似文献
65.
采用共沉淀法、均相沉淀法以及反相微乳法制备了铈锆复合氧化物.通过XRD,TEM,BET等表征手段来分析所得铈锆氧化物粉体的性质,将制得的粉体涂覆在堇青石蜂窝陶瓷载体上作为涂层,担载一定量的贵金属Pt作为活性组分制得整体催化剂,并在低温水汽变换反应上考察它们的催化性能.分析结果表明3种方法都得到了单相的铈锆固溶体;微乳法制得的纳米级铈锆固溶体粒径分布均匀、平均粒径尺寸为6 nm;所得纳米级铈锆复合氧化物的比表面积大小为微乳法>均相沉淀法>共沉淀法.实验结果表明用微乳法制得的铈锆复合氧化物的催化性能要优于其他两种方法. 相似文献
66.
67.
Introduction The development of chiral substances, especially inthe pharmaceutical field, places increasing demands onanalytical methods for the separation of these kinds ofisomers and the chiral purity control of drugs in phar-macokinetic studies. As the enantiomers of epinephrineand salbutamol have different pharmacological andtoxicological characteristics, separation and quantitationof the single enantiomers are required. Analytical methods used so far for the enantiomerseparation inclu… 相似文献
68.
A Novel Method for Preparing Polyurethane Based Conductive Composites with Low Percolation Threshold 总被引:1,自引:0,他引:1
JiWenHU MingWeiLI MingQiuZHANG: GenShuiCHENG MinZhiRONG 《中国化学快报》2004,15(8):1001-1004
A novel method for preparing conductive carbon black filled polymer composites with low percolation threshold from polyurethane emulsion are reported in this paper. The experimental results indicate that with a rise in carbon black concentration the insulator-conductor transition in the emulsion blended composites occurs at 0.8-1.4vol%. In contrast, the solution blended composites exhibit drastic increase in conductivity at conducting filler fraction as high as 12.3-13.3vol%. It is demonstrated that the composites microstructure rather than chemical structure of the matrix polymer predominantly determines the electrical conduction performance of the composites. 相似文献
69.
The synthesis of 4,5-dihydro-1H,3H-cycloprop[f]inden-4-ol ( 1 ) and diethyl 4,5-dihydro-1H,3H-cycloprop[f]-indene-4,4-dicarboxylate ( 26 ) starting from diene 4 is described. The cyclopentene ring is constructed by condensation of diethyl malonate to the dibromide 21 . The key-step in the synthesis of 1 consists in a twofold Curtius degradation of 22 , with subsequent reduction of the carbonyl group and aromatization. The skeleton of the isomer 31 is synthesized via cycloaddition of butadiene to cyclopent-4-ene-1,3-dione ( 7 ) and addition of dichlorocarbene to the adduct 27 after ketalisation. The attempted synthesis of dihydrocycloprop[f]indene ( 2 ) by base-induced elimination of several appropriately substituted precursors failed. 相似文献
70.