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A SnO2/Ti
electrode prepared by thermal oxidation was used as the anode for galvanostatic
electrolysis in acidic solution containing phenol, the time-dependances of phenol
concentration,chemical oxygen demand in solution(COD)and instantaneous current efficiency
were determined during electrolysis.The results show that with the SnO2/Ti
anode instead of Pt,the COD significantly decreases at the same charge passage, and
average current efficiency of oxidation increases by three times The mechanism for phenol
oxidation at two electrodes was discussed. 相似文献
123.
分子电子学已成为21世纪研究的热点. 通过将具有特定功能的分子连接在纳米尺度金属电极之间从而构筑包括分子导线、开关、整流器在内的各种分子尺度电子器件, 这引起了科学家们广泛的研究兴趣. 在分子电子学研究中, 构筑金属/分子/金属(MMM)分子结是研究分子器件中电子传输性质的关键. 尽管已经取得了很大的进展, 目前在纳米尺度下构筑稳定可靠的MMM分子结并测试单个分子的电学性质仍然面临很多挑战. 本文着重对单分子电学性质的测试技术和相关理论研究的最新进展以及存在的挑战做了概述. 相似文献
124.
Li Zha Renzhong Feng~* 《高等学校计算数学学报(英文版)》2007,16(4):348-357
In this paper,a new quasi-interpolation with radial basis functions which satis- fies quadratic polynomial reproduction is constructed on the infinite set of equally spaced data.A new basis function is constructed by making convolution integral with a constructed spline and a given radial basis function.In particular,for twicely differ- entiable function the proposed method provides better approximation and also takes care of derivatives approximation. 相似文献
125.
Jin Yan WANG Shu De XIAO Xi Gao JIAN* Department of Polymer Science & Materials Dalian University of Technology Dalian 《中国化学快报》2003,14(4)
Aromatic polyimides are distinguished for their excellent mechanical and thermal properties in many engineering fields1. However, aromatic polyimides are normally insoluble in common organic solvents, which restricts their applications in some fields. Many efforts have been taken to improve their solubility. Introducing bulky side groups and non-coplanar structure into polymers bone chains is a good way to obtain the polymers with excellent mechanical and thermal properties2. In this paper… 相似文献
126.
Ling Jun LI Xin Ying ZHANG* Gui Sheng ZHANG* School of Chemical Environmental Sciences Henan Normal University Key Laboratory of Environmental Science Engineering of Henan Education Department Xinxiang 《中国化学快报》2004,(5)
~~An Efficient and Green Procedure for the Preparation of gem-Dicar- boxylates from Aldehydes Catalyzed by Fe_2(SO_4)_3·xH_2O~~ 相似文献
127.
YU Zhaoxian LIU Yehou * 《Chinese Journal of Lasers》1998,7(4):363-367
1IntroductionItiswelknownthatbosonrealizationapproachisveryefectivetostudytherepresentationtheoryofgroup,andthebosonrealizat... 相似文献
128.
Ye Hua SHEN Hai Bo WANG Quan BAI Xin Du GENG* Institute of Modern Separation Science Shaanxi Provincial Key Laboratory of Modern Separation Science Northwest University Xi抋n 《中国化学快报》2003,(3)
Theinvestigationofproteinrenaturation,orrefoldinghasbecomeaveryhotpointinbothliquidchromatography(LC)andlifesciencefields.Besidesusualdilutionanddialysismethods,manynewmethodsconcernproteinrenaturationhavebeenpresented,suchasreversemicelles1,chaperones2,polyethyleneglycol(PEG)3,surfactant4andantibodies5etc.Oneoftheauthorssuggestedhighperformancehydrophobicinter-actionchromatography(HPHIC)tobeanewtoolforproteinrenaturation6.Areviewonproteinrenaturationwithliquidchromatography(LC)wasrecentl… 相似文献
129.
等离激元效应在光催化体系中的集成为实现广谱光吸收提供了一个新的途径,然而等离激元热电子的较低迁移率和不确定扩散方向使得其光催化效率仍较低.等离激元金属与n型半导体接触后,其界面间会形成肖特基结.在特定波长太阳光照射下,等离激元金属将其表面等离子体能量聚集在表面自由电子上,进而产生热电子.当这些热电子具有的能量高于肖特基势垒时,热电子便可注入到半导体导带上.与此同时,半导体上的电子可以通过肖特基接触发生回流,与金属上的空穴复合,进而降低半导体-等离激元金属复合材料的光催化性能.因此,为了提高光催化效率,如何调控等离激元热电子迁移和充分利用等离激元效应是一个重要挑战.本文尝试将"表面异质结"与肖特基结相结合的复合结构,得以有效地调控等离激元热电子的迁移.在该复合结构中,金纳米颗粒和铂纳米颗粒分别作为等离激元吸光单元和助催化剂,集成在TiO_2纳米片表面.其中"表面异质结"是由TiO_2纳米片的两种不同表面晶面所构成,我们选择由{001}和{101}两组晶面组成的TiO_2纳米片作为半导体衬底.该结构中的{001}晶面导带能级高于{101}导带能级,因而电子由高能级的{001}流向低能级的{101}晶面,可以用来引导等离激元热电子从可见光响应的金纳米颗粒向TiO_2进行高效转移.通过巯基丙酸的桥联作用,将等离激元Au纳米颗粒锚定在TiO_2纳米片的{001}晶面上,获得Au-TiO_2{001}样品.另一方面,利用TiO_2纳米片自身光生电荷导向性光沉积,得到与{101}晶面结合形成的Au-TiO_2{101}样品.我们对两组样品进行光电流和光催化产氢实验对比,确认在"表面异质结"诱导下Au-TiO_2{001}样品中Au产生的光生热电子可以更好地注入到TiO_2纳米片导带上.我们进一步通过光沉积Pt纳米颗粒来判定光生电子所能到达的区域,验证了以上结论.与此同时,肖特基结由铂纳米颗粒与TiO_2纳米片所形成,可以促使电子由TiO_2向铂纳米颗粒进行转移,而避免发生向金纳米颗粒的反向迁移,从而在Au-TiO_2体系中实现高效的单向载流子转移.基于该设计,等离激元光催化剂实现了明显改善的全谱光催化产氢性能.本文为全谱光催化的复合结构理性设计提供了一个新的思路. 相似文献
130.
Xing Zhou LI Ke Mei WU Dao Fei HUANG Liang HUANG* Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College. Xian Nong Tan St. Beijing 《中国化学快报》2002,13(6):528-530
(-) Clausenamide (1) showed strong nootropic action, while its (+) antipode had no such an action. The content of CM1(2) in the metabolites of (-)1 is much higher than that of (+)11. For comparing the nootropic activity of enantiomers, (+) and (-) CM1 were synthesized. CM1 is the hydroxylated product of the N-methyl group of clausenamide. Oxidation of the C3-OH and C6-OH protected clausenamide to introduce the hydroxyl group into the methyl was tried but unsuccessful. Then de novo s… 相似文献