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961.
962.
在光照条件下,光催化剂TiO2有很强的氧化能力,能有效降解水中的有机污染物[1],因而日益受到人们的关注.目前,研究最多的胶体溶液和颗粒悬浮体系因其难于分离、回收而限制了实际应用,因此催化剂固定问题急需解决.近年来,国内外对TiO2薄膜催化剂做了许多探索[2,3],取得了一些进展.本文用溶胶-凝胶法制备了一种粉末状TiO2光催化剂和两种薄膜型TiO2光催化剂,并进行了结构和形貌的表征,对敌敌畏稀释液做了光催化降解实验,并与粉末状TiO2进行对比.结果表明:薄膜TiO2催化剂优于粉末TiO2催化剂. 相似文献
963.
Azo compounds are widely utilized as dyes and analytical reagents.They can also be used as materials for non-linear optics and for storage optical information in laser dish[1]. Recently, many noteworthy studies have shown that azobenzene derivatives possess excellent optical memory and photoelectric properties[2]. The preparation of ordinary azo compounds has been described in many references. However, those compounds generally bear alkyl or aryl groups on both sides of the azo linkage (-N=N-). 相似文献
964.
We report the study of Stark effect of polarons in infinite parabolic quantum wells under an electric field, taking into account the effects of interaction with bulk LO-phonons. The electron-phonon interaction and the.effective mass in the plane perpendicular to the growth direction for excited states of free polarons have been calculated as functions of the degree of confinement. The general behavior of the excited states is found to be in agreement with previous works on the ground state. It is shown that in the limit of strong confinement the differences in electron-phonon interaction and effective mass between the ground state and excited states vanish. Although the applied electric field has no effect on the electronphonon interaction or the effective mass of a free polaron system, our numerical results for an AlGaAs parabolic quantum well have demonstrated its significance in determining the coupling of electrons with bulk LO-phonons of bound polaron systems. 相似文献
965.
Chen Guangpei Yuan Ye Mao Zepu Bai Jinzhi Sun Hansheng Liu Jing Li Weiguo Zhang Changchun Yan Wuguang Li Peiqin Qiu Jinfa Yang Jie Yang Chunmin Rong Gang Zhen Jianping Zhao Haiwen Zhao Meng Xie Yu 《中国物理C(英文版)》1998,22(11):982-989
This paper describes the algorithm of the non-numerical pattern recognition used in the VC of BES-Ⅱ. The code is good to provide the spacial resolution and the effeciency of the track found by M.C. data and experimental data. 相似文献
966.
A microscopic framework of sdlBM-2 is extended to the one of sdglBM-2. lntroducing hexadecupole pairing force, Hamdltonian and E2,E4 operators of the sdglBM-2 are deduced microscopically. The nucleus 24Mg in the light-mass region is chosen as the first application of such an extended microscopic approach. Based on strong coupling picture, spectrum, reduced E2 transition rates and reduced E4 transition matrix elements are calculated. The calculated results fit experimental results quitewell. 相似文献
967.
A novel thermosensitive interpenetrating network (IPN) hydrogel was prepared from an aqueous solution of poly[3,3‐dimethyl(methacryloyloxyethyl)propylammonium sulfonate] infiltrating a crosslinked sulfobetaine polymer, poly(2‐acrylamido‐2‐methylpropylsulfonic acid). The IPN gel shows an upper critical solution temperature (UCST) depending on the molar ratio of the components and the presence of salt. In contrast to conventional gels, the IPN gel exhibits no volume phase transition after traversing the UCST. 相似文献
968.
手性和手性物质的重要性已不言而喻,手性药物的开发也已成为主要发展趋势,但目前仍有部分手性药物以消旋体的形式出售和使用。如何合理、有效地使用这些消旋体药物,一直是值得深入研究的课题。对映体选择性释放将手性拆分和控释两个概念结合于一体,有望为消旋体药物的使用提供新的途径。基于本课题组的研究,本文综述了近年来对映体选择性释放研究领域所取得的主要进展。为便于讨论,本文根据构成药物控释载体的手性分子或结构(手性因素),将手性药物释放体系分为有机材料(水凝胶和粒子等)、无机材料和分子印迹材料等控释体系。关于对映体选择性释放以及释放过程中的对映选择性作用的研究,可进一步提升我们对于手性、手性物质和手性作用的认识。 相似文献
969.
This paper focuses on the issue of resilient dynamic output-feedback (DOF) control for ${{ \mathcal H }}_{\infty }$ synchronization of chaotic Hopfield networks with time-varying delay. The aim is to determine a DOF controller with gain perturbations ensuring that the ${{ \mathcal H }}_{\infty }$ norm from the external disturbances to the synchronization error is less than or equal to a prescribed bound. A delay-dependent criterion for the ${{ \mathcal H }}_{\infty }$ synchronization is derived by employing the Lyapunov functional method together with some recent inequalities. Then, with the help of some decoupling techniques, sufficient conditions on the existence of the resilient DOF controller are developed for both the time-varying and constant time-delay cases. Lastly, an example is used to illustrate the applicability of the results obtained. 相似文献
970.
氮化镓(GaN)基蓝光和绿光激光器在投影显示、激光加工、激光照明、存储等领域具有重要的应用前景与广泛的市场需求.本文着重介绍了GaN基蓝光和绿光边发射激光器的技术难点和相应的解决方案.在GaN基蓝光与绿光激光器中,就制备高质量InGaN/GaN多量子阱、减少内部光学损耗、增加空穴注入效率等方面分别介绍了一些结构与工艺方面的优化方法.简要介绍了垂直腔面发射激光器(VCSEL)、分布式反馈激光器(DFB)的研究现状. 相似文献