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991.
一类矩阵方程的极小Frobenius范数双对称解 总被引:1,自引:0,他引:1
黄敬频 《应用数学与计算数学学报》2004,18(2):49-56
利用矩阵的广义奇异值分解,给出了实矩阵方程ATXA=B存在极小Frobenius范数双对称解的充要条件及其解的表达式. 相似文献
992.
Introduction Thelargecapacityandhighcellvoltageoflithium basedcells ,coupledwiththeirrelativelylowenvironmen talimpactmakethemanidealcandidateforportablepowersupplies .Studyonpresentmaterialsforlithiumionbatter iesfocusesonimprovingcycleabilityandincreasingca pacityofelectrodematerials.Asoneoftheimportantpartsoflithium ionbatteries ,anodematerialshavebeeninvestigatedintensively .Now ,carbonaceousmaterialsareusedinnearlyalllithiumionbatteriesbecauseoftheirhighcapacity (theoreticalcapaci tyof… 相似文献
993.
本文介绍了用荧光法测定了人体胃粘膜组织中过氧化脂质的含量。该方法用样量少,操作简单,灵敏度高。经回收和重复性实验表明,方法的准确度和精密度均符合要求。 相似文献
994.
稳态荧光及各向异性方法研究环糊精纳米管的生成 总被引:1,自引:0,他引:1
本文运用稳态荧光和稳态荧光各向异性方法,研究了双喹啉(BQ)和1,1’-(甲撑双-1,4-苯基)二顺丁烯二酰亚胺(MDP-BMI)分子分别与α-,β-,和γ-环糊精(CD)的作用。实验结果表明,这两个客体分子与不同环糊精的作用不同。它们均可以和γ-CD生成纳米管状聚集物,在MDP-BMI-β-CD体系中也有纳米管存在,而在其它情况下,只有简单的环糊精包合物生成。 相似文献
995.
996.
ZHANG YunNan LIN LiQiong & ZHONG HuaiJie School of Mathematics Computer Science Fujian Normal University Fuzhou China Mathematics Information Science College Hebei Normal University Shijiazhuang College of Mathematics Computer Science Fuzhou University Fuzhou 《中国科学 数学(英文版)》2011,(4)
This paper studies the structure of operators on Σ1e type Banach spaces.It solves the problem of the small compact perturbations of operators with connected spectra.Namely,it shows that every operator with a connected spectrum on separable Σ1e type Banach spaces is a small compact perturbation of a strongly irreducible operator.Based on this result,this paper establishes the approximate Jordan forms of operators on Σ1e type Banach spaces with Schauder bases. 相似文献
997.
In this article, we construct some spacelike austere submanifolds in pseduoEuclidean spaces. We also get some indefinite special Lagrangian submanifolds by constructing twisted normal bundle of spacelike austere submanifolds in pseduo-Euclidean spaces. 相似文献
998.
DJpsiFDC is an event generator package for the process gg→J/ψJ/ψ. It generates events for primary leading-order 2→2 processes. The package could generate a Les Houches Event (LHE) document and this could easily be embedded into detector simulation software frameworks. The package is produced in Fortran code. 相似文献
999.
WANG Ying FU Ai-ping LI Hong-liang TIAN Feng-hui YUAN Shu-ping SI Hong-zong DUAN Yun-bo WANG Zong-hua Institute for Computational Science Engineering Laboratory of New Fiber Materials Modern Textile Growing Base for State Key Laboratory College of Chemical Environmental Engineering Qingdao University Qingdao P.R.China 《高等学校化学研究》2011,(4):673-677
The effects of two different amino acid catalysts on the stereoselectivities in the direct Mannich reactions of cyclohexanone,p-anisidine and p-nitrobenzaldehyde were studied with the aid of density functional theory.Transition states of the stereo-determining C C bond-forming step with the addition of enamine intermediate to the imine for the L-proline(·-amino acid) and (R)-3-pyrrolidinecarboxylic acid(·-amino acid)-catalyzed processes were reported.B3LYP/6-31G calculations provide a good explanation for t... 相似文献
1000.
CHEN Hong WEI Ying-jin WANG Chun-zhong CHEN Gang .College of Materials Science Engineering Jilin University Changchun P.R.China .College of Physics Beihua University Jilin .State Key Laboratory of Superhard Materials College of Physics 《高等学校化学研究》2011,(4):669-672
Li0.33MnO2 cathode material was synthesized by solid state reaction which showed a monoclinic structure.In situ synchrotron diffraction showed a reversible structural transition of Li0.33MnO2 during Li+ insertion/extraction.However,it is difficult to determine the crystal structure of lithiated Li0.33+xMnO2 based on their poorly resolved diffraction patterns.This difficulty was successfully resolved by X-ray absorption spectroscopy(XAS) and Raman scattering which are sensitive to the short-range ordering of... 相似文献