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41.
B离子掺杂TiO2催化剂(TiO2-xBx)光催化活性的研究 总被引:3,自引:0,他引:3
采用溶胶-凝胶法制备出纳米TiO2和TiO2-xBx催化剂. 光催化实验证明, TiO2-xBx催化剂的紫外、可见光催化活性均高于TiO2. XRD, XPS和Raman结果表明, B离子是以取代式掺杂占据了TiO2的O2-的晶格位置. UV-Vis和PL谱的结果表明, B离子的2p轨道与O的2p轨道形成混合价带, 产生可见光响应, B离子的掺入有效地阻止了光生载流子的复合, 促进了其分离, 是TiO2-xBx催化剂紫外、可见光催化活性提高的主要原因. 相似文献
42.
Zhixiong TAO 《数学年刊B辑(英文版)》2016,37(5):767-776
The author discusses 2-adjacency of two-component links and study
the relations between the signs of the crossings to realize
2-adjacency and the coefficients of the Conway polynomial of two
related links. By discussing the coefficient of the lowest $m$ power
in the Homfly polynomial, the author obtains some results and
conditions on whether the trivial link is 2-adjacent to a nontrivial
link, whether there are two links 2-adjacent to each other, etc.
Finally, this paper shows that the Whitehead link is not 2-adjacent
to the trivial link, and gives some examples to explain that for any
given two-component link, there are infinitely many links 2-adjacent
to it. In particular, there are infinitely many links 2-adjacent to
it with the same Conway polynomial. 相似文献
43.
通过在基于高双折射光纤Sagnac干涉仪的Sagnac环内增加一段高双折射光纤并控制两段高双折射光纤的熔接角度,设计制作了二阶Loyt-Sagnac干涉仪结构.利用Jones矩阵对反射谱特性进行了理论推导,对光束入射角度和高双折射光纤长度进行了优化,并对两种结构的干涉仪温度传感器进行仿真和实验.仿真结果表明,利用二阶Loyt-Sagnac干涉仪结构的游标效应,能提高其作为温度传感器时的灵敏度;实验结果证明,单段Sagnac环干涉仪温度传感器灵敏度为-1.46nm/℃,而使用二阶Loyt-Sagnac干涉仪的温度传感灵敏度为-17.99nm/℃,提高了约12.32倍. 相似文献
44.
In this paper, we investigate the oscillation of a fullerene that is moving within the centre of a bundle of nanotubes. In particular, certain fullerene–nanotube bundle oscillators, namely C60-carbon nanotube bundle, C60-boron nitride nanotube bundle, B36N36-carbon nanotube bundle and B36N36-boron nitride nanotube bundle are studied using the Lennard–Jones potential and the continuum approach which assumes a uniform distribution of atoms on the surface of each molecule. We address issues regarding the maximal suction energies of the fullerenes which lead to the generation of the maximum oscillation frequency. Since bundles are also found to comprise double-walled nanotubes, this paper also examines the oscillation of a fullerene inside a double-walled nanotube bundle. Our results show that the frequencies obtained for the oscillation within double-walled nanotube bundles are slightly higher compared to those of single-walled nanotube bundle oscillators. Our primary purpose here is to extend a number of established results for carbon to the boron nitride nanostructures. 相似文献
45.
Naonori Kita 《Optical Review》2009,16(3):305-312
Optimizing the polarization characteristics of an optical system is generally a complicated problem, unlike the case of optimizing
scalar characteristics such as pupil function. Here, we will propose a linear approximation approach to solve this problem
systematically and define the conditions to be satisfied to make the approximation accurate. This approximation scheme is
constructed by naturally extending a concept of the scalar imaging theory. 相似文献
46.
石英晶体右旋光与左旋光折射率差的温度特性 总被引:2,自引:1,他引:1
利用Jones矩阵,从理论上分析了石英晶体的旋光特性。在-10~60℃的温度范围内,实验测试了石英晶体的旋光角随温度的变化关系,并得出了石英晶体右旋圆偏振光与左旋圆偏振光折射率差随温度的变化关系。结果表明,对单色光来说,石英晶体右旋光与左旋光折射率差随温度的升高而增加,也就是说,石英晶体的旋光率随温度变化的这一特性是由晶体的右旋圆偏振光与左旋圆偏振光的折射率差随温度的变化引起的。 相似文献
47.
48.
We present new generalized-ensemble molecular dynamics simulation algorithms, which we refer to as the multibaric-multithermal molecular dynamics. We describe three algorithms based on (1) the Nosé thermostat and the Andersen barostat, (2) the Nosé-Poincaré thermostat and the Andersen barostat, and (3) the Gaussian thermostat and the Andersen barostat. The multibaric-multithermal simulations perform random walks widely both in the potential-energy space and in the volume space. Therefore, one can calculate isobaric-isothermal ensemble averages in wide ranges of temperature and pressure from only one simulation run. We test the effectiveness of the multibaric-multithermal algorithm by applying it to a Lennard-Jones 12-6 potential system. 相似文献
49.
50.