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941.
942.
943.
YUEBin JIANGLei HUChang-wen CHENJian-min HEHe-yong 《高等学校化学研究》2005,21(4):386-390
Paratungstate-loaded titania catalysts were prepared via the addition of a series of aqueous solutions of paratungstate( denoted as W7 ) into an isopropanol solution of Ti[ OCH( CH3 )2 ]4 by means of the sol-gel method. The catalysts were characterized by EDX, BET, FTIR, UV-Vis DRS, XRD and the results indicate that such paratungstateloaded catalysts maintained their heptatungstate structure in the anatase titania matrix up to 400℃. The catalysts were tested for the heterogeneous photodegradation of chlorobenzene in aqueous media and showed a better catalytic activity than P-25 TiO2 because paratungstate can prevent the recombination of the holes and electrons produced during irradiation. Moreover, the paratungstate-loaded titania catalysts can resist the disaggregation during the photoirradiation and can be easily recycled from the aqueous suspensions after reactions. 相似文献
944.
Jian Zhi SUN Xiao Chuan DENG Shu Bin WEI Fa Qiang LI Pei Hua MA 《中国化学快报》2005,16(10):1401-1404
A new kind of adsorbent Li(1+x)AlxTi(2-x)(PO4)3 was synthesized by solid state reaction method. The influence of the content of doping aluminum on the adsorbent Li(1+x)AlxTi(2-x)(PO4)3 was investigated by XRD, while the morphology of powders was observed by SEM. The investigation of the adsorption properties showed that the adsorbent can selectively adsorb sodium with the adsorption capacity of 11.76 mg/g. The optimum conditions of adsorption are at pH 10.0-11.0 in LiCl solution. 相似文献
945.
Grafting polymer glycols onto nano-silica surface through one-step procedure was investigated. The major characteristic of this procedure is that all the materials and reagents (silica, PEG, TDI, DBTDL, solvent) required for grafting were added simultaneously into the reaction vessel. TDI and DBTDL were used as coupling agent and catalyst, respectively.The products were characterized by FTIR, TGA, elemental analyses and TEM, giving evidence for successful grafting of PEG. Possible mechanism of this grafting was studied and two grafting processes were proposed. The process through which the grafting proceeds depends on the reaction temperature. Effect of molecular weight of PEG on grafting was also investigated. 相似文献
946.
947.
Shu Xia LIU* Chun Mei WANG Hong Ju ZHAI De Hui LI En Bo WANG Institute of Polyoxometalate Chemistry Department of Chemistry Northeast Normal University Changchun 《中国化学快报》2004,15(2):216-219
Heteropolyoxometalates are a large family of potent medicines due to their excellent antiviral and antitumor activity 1-4, while their application in clinic meets great difficulties for their toxicity 5. How to synthesize heteropolyoxometalate medicines possessing high activity and low toxicity has become the focus in heteropolyoxometalate medicine research. Previously reported polyoxometalates showing medical activities are all salts simple Na+, K+ or NH4+ etc. inorganic cations, in which o… 相似文献
948.
含羧基的含氟嵌段共聚物的合成及表面性能研究 总被引:6,自引:0,他引:6
利用原子转移自由基聚合反应以及随后的大分子链中叔丁酯基团的水解反应,合成了一系列具有不同含氟量和羧基含量的二嵌段共聚物,并分别通过GPC, 1H NMR和FT-IR对共聚物的组成和结构进行了表征.进一步考察了这些含羧基或羧酸钠基团的含氟嵌段共聚物在吡咯烷酮或水中的溶解性能、临界胶束浓度、表面活性、达到饱和吸附时每个分子在表面所占据的面积,以及成膜后的临界表面张力等性能.实验结果表明,此含氟嵌段共聚物能显著降低吡咯烷酮和水的表面张力,成膜后表现出与聚四氟乙烯极为接近的低表面能特性. 相似文献
949.
950.
分子信标荧光探针用于抑癌基因ING1表达产物的定量测定 总被引:6,自引:0,他引:6
根据抑癌基因ING1基因的序列设计并合成了检测ING1转录产物的分子信标核酸探针,发展了一种快速测量从正常细胞系和鼻咽癌肿瘤细胞系提取的ING1转录产物的方法,所得结果与用逆转录结合PCR法(RT-PCR)得到的结果相吻合.并且,将能表达ING1基因的质粒转入肿瘤细胞进行培养后,再将分子信标转入肿瘤细胞,发现转导了质粒的肿瘤细胞比未转导质粒的肿瘤细胞内的荧光明显增强,从而进一步证实了所设计的分子信标核酸探针与ING1转录产物的结合. 相似文献