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31.
以钛酸四丁酯为前驱体,十六烷基三甲基溴化铵(CTAB)为模板剂合成了高比表面的TiO2超细纳米粉体。采用XRD、TEM、BET分析方法对催化剂的物相、颗粒粒径及比表面积进行了表征,结果显示TiO2的晶粒尺寸和比表面积与CTAB添加量和焙烧温度有关。重点考察了不同条件下制备的TiO2系列光催化剂无氧条件下的光催化分解水产氢性能。实验结果表明,当CTAB与Ti的投料的物质的量之比为0.15,焙烧温度为450 ℃时,获得的晶粒尺寸为5.73 nm、比表面为150 m2·g-1的TiO2粉体具有最好的光催化产氢活性,测得的3 h内平均产氢速率为12.5 mL·h-1。 相似文献
32.
We report the construction of an optical tweezers system and the results of the trapping and the moving of living algal cells. Experimental study on trapping polystyrene spheres demonstrates the effects of the system parameters on the trap. The trapping forces on dielectric spheres are calculated using Ashkin's ray-optics model. The result shows that an objective with higher numerical aperture can build a more stable trap along axial direction than an objective with lower numerical aperture, though their transverse trapping forces are on the same order. 相似文献
33.