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11.
1 Results In this contribution we deal with photophysical and photoelectrical study of novel fluorene-thiophene copolymers, and thiophene-based oligomers and polymers, the syntheses of which are reported in our other contributions. Information about electronic structure of the polymers was obtained from cyclic voltammetry and absorption spectroscopy. The absorption of the polymers under study covers the whole visible region; the low band-gap polymer (Eg=1.35 eV) exhibited the long-wavelength absorption ... 相似文献
12.
本文介绍一种采用纯双相光栅进行激光束相干相加的方法。用一光栅能把单一光束高效率地分离成N个相等级次激光束,亦能以相同效率把N个相等级次的激光束转换成单一光束。实验证明,它能以75%的总转换效率将七束激光转换成一个单束激光。本文还描述一种实验装置,将两束氦-氖激光与三束氦-氖激光(波长为3.39μm)的功率合成,其效率可高达83%。 相似文献
13.
Pan Yifei Department of Mathematical Sciences Indiana University-Purdue University Fort Wayne Fort Wayne IN - U.S.A. School of Mathematics Informatics Jiangxi Normal University Nanchang China 《中国科学A辑(英文版)》2005,48(Z1)
It is proved that every proper holomorphic self-map of a smooth bounded Reinhardt domain of D'Angelo finite type in Cn (n > 1) is an automorphism. 相似文献
14.
Dissociative Chemisorption of an H2(v,j) Molecule on Rigid Ni (100) Surface: Dependence on Surface Topologies and Initial Rovibrational States of the Molecules 下载免费PDF全文
MeryemEvecen MustafaBǒyǚkata MehmetCivi ZiyaB.Gǚvenc 《中国物理快报》2005,22(2):420-423
The H2(v,j) Ni(100) collision system has been studied to understand the effects of the surface sites and initial rovibrational states of the molecule on molecule-surface interactions, by a quasiclassical molecular dynamic simulation method. Dissociative adsorption of an H2 molecule on the rigid Ni(100) surface is investigated at topologically different three sites of the surface. Interaction between the molecule and Ni surface was described by a London-Eyring-Polani-Sato (LEPS) potential. Dissociative chemisorption probabilities of the H2(v, j) molecule on various sites of the surface are presented as a function of the translation energies between 0.001-1.0eV. The probabilities obtained at each collision site have unique behaviour. At lower collision energies, indirect processes enhance the reactivity, effects of the rotational excitations and impact sites on the reactivity are more pronounced. The results are compared with the available studies. The physical mechanisms underlying the results and quantum effects are discussed. 相似文献
15.
A.R.ELAMROUSS 《数学学报(英文版)》2005,21(1):129-142
This paper contains a generalization of the well-known Palais-Smale and Cerami compactness conditions. The compactness condition introduced is used to prove some general existence theorems for critical points. Some applications are given to differential equations. 相似文献
16.
Li-ming Wu~ Zheng-liang Zhang~ Laboratoire de Mathématiques Appliquées.CNRS-UMR Université Blaise Pascal Aubière France 《应用数学学报(英文版)》2004,(3)
Using the method of Girsanov transformation,we establish the Talagrand's T_2-inequality for dif-fusion on the path space C([0,N],R~d) with respect to a uniform metric,with the constant independent of N.This improves the known results for the L~2-metric. 相似文献
17.
Quan Sen JIU Department of Mathematics Capital Normal University Beijing P.R.China Cheng HE Institute of Applied Mathematics Academy of Mathematics System Sciences Chinese Academy of Sciences Beijing P.R.China 《应用数学学报(英文版)》2004,(4)
In this paper we are interested in the sufficient conditions which guarantee the regularityof solutions of 3-D ideal magnetohydrodynamic equations in the arbitrary time interval [0,T].Fivesufficient conditions are given.Our results are motivated by two main ideas:one is to control theaccumulation of vorticity alone;the other is to generalize the corresponding geometric conditions of3-D Euler equations to 3-D ideal magnetohydrodynamic equations. 相似文献
18.
Nanoporous Structure in Low-Dielectric Films with Positronium Annihilation Lifetime Spectroscopy 下载免费PDF全文
We investigate nano-porous structures in thin low-dielectric films, i.e. the pore sizes, distributions, and interconnectivity, by using depth profiled positronium annihilation lifetime spectroscopy (PALS). It is found that PALS has good sensitivity to probe both interconnected and closed pores in the range from 0.3nm to 3Onto, even in the film buried beneath a diffusion barrier. A series of low dielectric constant films of organosilicon-silsequioxane with different weight percentages of porogen have been comparatively investigated. The PALS technique can be used to distinguish the open porosity from the closed one, to determine the pore size, and to detect the percolation threshold with the increasing porosity that represents the transition from closed pores to interconnected pores.Furthermore, the pore percolation length can be derived. 相似文献
19.
I.IntroductionWhenastructurcvibratcs,itsvibratingsurfacewillmakesurroundingmediummovetogethcrwithit.Ifthernotionissofastthatthcmediumroundthestructureproduccaloca1contractionandcxpansionandthcypropagatefaraway,thesoundradiationisformed.Itispossiblctodcscribeanalytica11ytheradiationfic1dofsimplyandregularlyshapcdsourcessuchaspointsoundsourccs,spherica1soundsourccsandinflnite1engthllnearsoundsourccs,butitisa1mostimpossib1ctosolvetheradiationfiledbyanyanalyt-ica1methodforsourcesofvcrycomplicateds… 相似文献
20.
I.IntroductionThepcrformanccsofAcousto-optic(AO)dcviccareoftenlimitcdbythepropertiesofAOmcdiawhenitisusedinAOsigna1processingsystems.Thespectrumanalyzersandcorre1ationreceivers,forinstancc,areexpcctcdtoimprovcthereso1utionanddynamicrangcwhilereducingtheproccssorvolume.Rccent1y,ancwclassofmateria1s,themercurousha1ides,promiscstocontributeimportantsolutionstosuchnccdsandisrefincdtopractica1uti1izations.Themecurousha1ideweconsidcrinthispapcrismecurouschloride(Hg,C1,).Thesing1ecrystalofHg,Cl… 相似文献