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排序方式: 共有646条查询结果,搜索用时 546 毫秒
641.
ZHENG Yue qing * 《高等学校化学研究》1999,(3)
IntroductionPreviously,wereportedthecrystalstructureofK2[Ni(CO3)2(H2O)4][1],whichcrystallizedinthebaylissitetypestructureandwasfoundtobeisostructuralwithK2[Co(CO3)2(H2O)4][2]andK2Mg(CO3)2·4H2O[3].Inordertosystematicallyinvestigatetheoccurrenceoftheco… 相似文献
642.
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
643.
IntroductionAmrinon,asyntheticbipyridinederivative,nonglycosideandnoncatecholaminecar-diotonicstimulant,iscurrentlyusedinthetreatmentoftheheartfailureandforcardiovascu-larsupportinpediatricpatients.Itpossessespotentcardiacandbloodvesselspreadingef-fe… 相似文献
644.
铁和铈共掺杂二氧化钛中的协同效应 总被引:2,自引:0,他引:2
The co-doping of iron and cerium into TiO2 was studied by means of X-ray diffraction, Raman spectroscopy, UV-Vis diffuse reflectance spectroscopy and X-ray photoelectron spectroscopy. when separately doping via the sol-gel method, iron was introduced in the framework of anatase TiO2 whereas cerium was not; interestingly, both iron and cerium were introduced in the framework when co-doping by the sol-gel method. The co-doped TiO2 behaves much more intense surface hydroxyl concentration than the separately-doped and pure TiO2. This observation demonstrates for the first time a cooperative effect in the co-doping of transitional metals in the framework of TiO2. 相似文献
645.
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
646.
Weinan E~* Jianfeng LU~ 《数学年刊B辑(英文版)》2007,28(6):665-676
The authors consider the simplest quantum mechanics model of solids,the tight binding model,and prove that in the continuum limit,the energy of tight binding model converges to that of the continuum elasticity model obtained using Cauchy-Born rule.The technique in this paper is based mainly on spectral perturbation theory for large matrices. 相似文献