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采用直接真空吸附钛酸四丁酯后水解法制备了以活性炭为载体的负载型TiO2光催化剂,以间二氯苯为探针分子研究了催化剂光催化降解反应性能.实验结果表明:随着热处理温度的不同,催化剂的光催化活性有很大的变化.对催化剂多次反复使用,其活性基本不变. 相似文献
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Theoretical Study on the Structure and Isomerization of CH_3SB 总被引:1,自引:0,他引:1
1 INTRODUCTION Solid boron and materials containing boron are po-tential excellent rocket fuel. Many studies arefocused in experiment and theory on the boroncompounds, among which simple boroncompound-HOB with simple structure can be readilyprepared. There are many reports on the experimentaland theoretical re- search results of the molecule aswell as unsaturated CH3NH=B and H2N=B exceptHOB. Very recently, some theoretical studies ofunsaturated CH3OB… 相似文献
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以聚芳醚三乙酸氯化铵树枝分子为稳定剂在乙醇水溶液中制备了金属Pt和Pd纳米粒子。通过UV-Vis、IR、TEM和XRD等方法对纳米粒子进行了表征。聚芳醚三乙酸氯化铵树枝分子根部3个乙酸基基团与金属纳米粒子表面原子间具有较强的相互作用,以其为稳定剂制备的Pt和Pd金属纳米粒子在溶胶中及反应过程中均表现出很好的稳定性。以间苯氧基苯甲醛催化加氢反应为模型反应,研究了Pt和Pd金属纳米粒子的催化反应性能。以Pt金属纳米粒子为催化剂,在常压,40 ℃下反应12 h,间苯氧基苯甲醛加氢转化率大于99%,在相同反应条件下Pt金属纳米粒子的催化加氢活性高于Pd金属纳米粒子。 相似文献
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利用导电高分子聚(3,4-二氧乙基噻吩)/聚(对苯乙烯磺酸)(PEDOT/PSS)作保护剂,制备了银纳米颗粒,用UV-Vis和TEM对其进行了表征.结果表明,选择合适量的PEDOT/PSS保护剂可以得到大小分布较窄银纳米颗粒. 相似文献
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制备了4-(双(4-(4-丁氧基苯乙烯基)苯基)氨基)苯甲酸(简称二烯酸,Dienoic Acid)保护的铂纳米颗粒,通过UV-Vis,TEM,XRD对其进行了表征.以间苯氧基苯甲醛的催化加氢反应为模型研究了其催化性能及影响催化活性的因素.实验结果表明:金属纳米粒子粒径随金属/稳定剂摩尔比的下降而减小,而催化加氢反应活性随金属/稳定剂摩尔比的上升而增加.在常压、40℃、n(醛)/n(催化剂)=523条件下,反应10 h可以获得纯度大于99%的间苯氧基苯甲醇. 相似文献
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PREPARATION,SUPERCONDUCTIVITY AND STRUCTURE OF THE LaBaCaCu3O7-x SUPERCONDUCTORS WITH Tc HIGHER THAN 80 K
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In this paper, the preparation process of the tetragonal LaBaCaCu3O7-x (LBCCO) superconductor with Tc=84 K is repored. The superconductivity and structure of the LBCCO superconducting phase are investigated by means of X-ray diffraction (XRD), transmission electron microscope(TEM) and superconductivity measurements, The results indicate that the superconducting phase with Tc=82K in the LBCCO system has a tetragonal structure with a=0.3966nm, c=l.1838nm and space group P4/mmm. About 50% of the Ca and La atoms are located in 1d sites (i.e. Y site in the YBCO structure). It is confirmed that there is in fact no orthorhombic to tetragonal transition in this material. The relationship between the oxygen content and Tc is also presented. 相似文献
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0引言粒径小于10nm的量子点,具有特殊的物理化学性质。如低电子转换性能、高氧化还原电位,高矫顽力,高催化性能等,金量子点还具有生物识别、生物传感器等性能[1]。纳米颗粒的合成与应用已经引起人们的广泛兴趣[2 ̄4],二维、三维量子点阵长程有序排布对将来的纳米电子器件及超功能性材料具有重要意义[5,6]。然而,二维、三维量子点阵长程有序排布需要单分散量子点。这就需要人们利用各种方法制备单分散量子点。直接合成法,如Lianos等[7,8],利用反胶束法合成出粒径为5nm量子点,但是单分散性不佳。目前,获得单分散纳米颗粒主要有3种方法,种子增… 相似文献