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521.
三甲川菁染料敏化TiO2纳米
结构电极的光电化学 总被引:1,自引:0,他引:1
The
photoelectrochemical behaviors of the TiO2 nanostructured porous film
sensitized by cyanine dye were investigated in this paper.The results showed that the
excitaed state level matched the conduction band edge of TiO2
nanoparticle.Therefore the sensitization of the dye can increase the photocurrent
intensity of the TiO2 nanostructured electrode obviously and results in a
red-shift of optical absorption from the ultra-violet region to the visible.As a
result,the light-to-electricity conversion efficiency was improved evidently,the maximum
value of IPCE has reached 12.1%. 相似文献
522.
IntroductionAmrinon,asyntheticbipyridinederivative,nonglycosideandnoncatecholaminecar-diotonicstimulant,iscurrentlyusedinthetreatmentoftheheartfailureandforcardiovascu-larsupportinpediatricpatients.Itpossessespotentcardiacandbloodvesselspreadingef-fe… 相似文献
523.
甲醇是一个重要的平台分子, 实现其高效转化为能源和化学品的关键是揭示相关反应过程中催化剂的结构与催化性能之间的关系和反应机理. 围绕这个关键问题, 以甲醇选择氧化为探针反应, 本文总结了负载氧化钼、负载氧化钒和杂多酸等典型催化剂体系以及近年来发展的氧化铼、氧化钌等新催化剂体系在认识催化活性中心结构和反应机理, 进而调控它们的氧化中心和酸中心等方面所取得的进展. 这些认识将有助于设计制备性能优异的新催化剂和实现甲醇到目标氧化产物的定向转化. 相似文献
524.
Synthesis and cytotoxic activity of novel curcumin analogues 总被引:3,自引:0,他引:3
Qin Zhang Yao Fu Hao Wei Wang Tao Gong Yong Qin Zhi Rong Zhang~* Key Laboratory of Drug Targeting Drug Delivery Systems Ministry of Education West China School of Pharmacy Sichuan University Chengdu China 《中国化学快报》2008,19(3):281-285
Five novel curcumin analogues bearing different substituents at 4-position of phenyl group were synthesized. Their structures were confirmed by NMR and HRMS spectrum. Their cytotoxic activities against six tumor cell lines were tested by the standard MTT assay in vitro. The results indicated that four analogues (1A-1C, 1E) with solubilizing moieties showed selective potent cytotoxicity against HepG2, HeLa and CT26 cell lines, and analogue 1A and 1C exhibited more potent cytotoxicity than curcumin against CT26 cell line. It was suggested that introduction of appropriate substituents to 4-position of phenyl group might be a potential option for structural modification of curcumin. 相似文献
525.
Gang Li 《高等学校计算数学学报(英文版)》2007,16(4):358-369
The Helmholtz equation is sometimes supplemented by conditions that include the specification of the boundary value of the divergence of the unknown.In this paper, we study the vector Helmholtz problem in domains of both C~(1,1)and Lipschitz.We es- tablish a rigorous variational analysis such as equivalence,existence and uniqueness. And we propose finite element approximations based on the uncoupled solutions.Fi- nally we present a convergence analysis and error estimates. 相似文献
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529.
IntroductionThispaperisconcernedwiththenumericalsolution ,byfinitedifferencemethod ,ofthefollowingsingularlyperturbednonlocalboundaryvalueproblem :Lu≡-εu″ +a(x)u=f(x) ( 0 <x<l) ,( 1 )L0 u≡-εu′( 0 ) +γu( 0 ) =μ0 , ( 2 )L1u≡u(l) -δu(d) =μl ( 0 <d<l) ,( 3 )whereεisasmallpositiveparameter,… 相似文献
530.
Qixiang Wang* Guoqing Ning Fei Wei Guohua Luo Department of Chemical Engineering Tsinghua University Beijing P. R. China *Author to whom correspondence should be addressed. 《中国颗粒学报》2003,(6)
1. Introduction Carbon nanotubes (CNTs), a kind of the most advanced nanomaterials with novel properties and promising for many applications, have aroused great interest of the world in a number of research fields (Iijima, 1991; Baughman et al., 2002; Iijima & Ichihashi, 1993; Rao & Govindaraj, 2002; Rueckes et al., 2000; Adrian et al., 2001; Javey et al., 2003). Catalytic chemical vapor deposition (CCVD) is re-garded as the most suitable method for the preparation of microstructured CN… 相似文献