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Min Wu Yan Lv Zhengping Fu Jiao Xu Ting Guo Yongxun Zhao 《Applied Surface Science》2010,256(23):7125-9486
The simultaneous Ag loaded and N-doped TiO2 hollow nanorod arrays with various contents of silver (Ag/N-THNAs) were successfully synthesized on glass substrates by one-pot liquid phase deposition (LPD) method using ZnO nanorod arrays as template. The catalysts were characterized by Raman spectrum, field-emission scanning electron microscopy (FESEM), high-resolution transmission electron microscope (HRTEM), ultraviolet-vis (UV-vis) absorption spectrum and X-ray photoelectron spectroscopy (XPS). The results suggest that AgNO3 additive in the precursor solutions not only can promote the anatase-to-rutile phase transition, but also influence the amount of N doping in the samples. The photocatalytic activity of all the samples was evaluated by photodegradation of methylene blue (MB) in aqueous solution. The sample exhibited the highest photocatalytic activity under UV light illumination when the AgNO3 concentration in the precursor solution was 0.03 M, due to Ag nanoparticles acting as electron sinks; When the AgNO3 concentration was 0.07 M, the sample performed best under visible light illumination, attributed to the synergetic effects of Ag loading, N doping, and the multiphase structure (anatase/rutile). 相似文献
74.
By using of the invariant theory, we have studied the geometric phase of quantum dots in the time-dependent isotropic magnetic
field, the dynamical and geometric phases are given, respectively. 相似文献
75.
H.-L. Zhang S.-F. Wang R. Wang J. Jiao 《The European Physical Journal B - Condensed Matter and Complex Systems》2010,73(4):489-493
The dislocation widths and Peierls stresses of glide dislocations and shuffle dislocations in graphene have been studied by
the improved Peierls-Nabarro (P-N) equation which contains the discrete correction. The discrete parameter is obtained from
a simple dynamic model in which the
interaction attributed to the variation of bond length and angle was considered. The restoring force in the improved P-N equation
is given by the gradient of the generalized stacking fault energy
surface (γ-surface). Our calculation shows that the widths of the shuffle dislocation and the glide dislocation are narrow
and the width of the shuffle dislocation is about twice wider than the glide dislocation. The Peierls stress of a shuffle
dislocation is one order of magnitude smaller than that of a glide dislocation. As a consequence, the shuffle dislocation
moves more easily than the glide dislocation. 相似文献
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VARIATIONAL CALCULATION ON GROUND-STATE ENERGY OF BOUND POLARONS IN PARABOLIC QUANTUM WIRES 总被引:1,自引:0,他引:1 下载免费PDF全文
Within the framework of Feynman path-integral variational theory, we calculate the ground-state energy of a polaron in parabolic quantum wires in the presence of a Coulomb potential. It is shown that the polaronic correction to the ground-state energy is more sensitive to the electron-phonon coupling constant than the Coulomb binding parameter, and it increases monotonically with decreasing effective wire radius. Moreover, compared to the results obtained by Feynman Haken variational path-integral theory, we obtain better results within the Feynman path-integral variational approach (FV approach). Applying our calculation to several polar semiconductor quantum wires, we find that the polaronic correction can be considerably large. 相似文献
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测量并分析了盐酸苯海拉明的红外光谱和拉曼光谱。在Raman光谱中, 1001 cm-1出现一个极强峰, 在1030 cm-1和618 cm-1各有一个中等峰,此外,在红外光谱中, 714 cm-1和757 cm-1附近出现极强的吸收峰,认定这个化合物中存在单取代苯。C-N的对称伸缩振动出现在837 cm-1, 1433 cm-1和1470 cm-1分别为CH2和CH3的变形振动, 在红外光谱中, 1020 cm-1处明显的吸收峰属于C-O-C反对称伸缩振动。此外, 测量得到含量为25 mg苯海拉明药片的拉曼光谱与纯苯海拉明的拉曼峰比较一致, 可作为无损快速检测该药物的手段。 相似文献
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