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161.
Recently,thestudyofrelationshipsbetweenstructureandpropertyforseriesofcompoundhavingenhancedopticalnonlinearityhasincreaseourunderstandingofwhatmolecularleveIdesigncriteriaareimPortantformaximizingthesecondandthethird-ordernonlinearity'.lngeneral,thesestudieshavefocusedonmanipulationoftheeffectiveconjugationlengthforavarietyofn-electronbackbones,mostlyrelatedto.-PvariousorganiccomPoundscontainingdonorandacceptorgroups'.InthispaPer,wewillstudytheinteractionamongdonor-metal-donorinx-conjugation…  相似文献   
162.
1 Introduction The investigation of supersonic radiation wave transporting in low density foam pro-duced by thermal radiation is of crucial importance in inertial confinement fusion (ICF) research[1]. When the intense radiation flux is incident in the media, first, a supersonic heat wave is formed which propagates into the undisturbed material. In time, due to the increasing mass of heated material, it slows down and is overtaken by a shock wave,thus becoming of the ablative type. Normally, …  相似文献   
163.
MicheliayunnanensisFr.exFin.etGagnisaChinesetraditionalmedicinefortreatmentofinflammation.Weobtainedanewsesquiterpene1,throughinvestigationoftheplant,togetherwithtwoknowncompoundsPhydroxyarbusculinAZIandparthenolide32.Compound1,needlecrystal,mp146"C,[a];z-2.56(c0.391,CHC13),displayedstrongabsorptionsforhydroxylandestergroups(3339cm-',3298cm',1750..-i,1742cm')inIR.HRFAB MSmlz:389.2168[(M l) ,Cafe.forC19H33OS:389.21751agreedwithmolecularformulaC19H32O8.Fourunsaturations,twoofwhichwer…  相似文献   
164.
在1984年,吴从炘、方锦暄和A.K.Katsaras分别提出了两种Fuzzy赋范空间的定义。这些概念既是赋范空间概念的自然推广,又是特殊的Fuzzy拓扑线性空间。在文[3~5]中,不仅考察了这两种定义之间的关系,还讨论了Fuzzy赋范空间的性质以及其上广义Fuzzy线性算子的连续性等。在本文中,我们将继文[4]给出Fuzzy赋范空间中子集有界性、稠密性的刻划条件并利用这些条件给出Fuzzy范数是诱出的充要条件。此外,作为诱出Fuzzy范数的推广,我们给出了两类Fuzzy范数的特征刻划。  相似文献   
165.
Using of data collected with the CLEO-c detector, we report on first observations and measurements of Cabibbo-suppressed decays of D mesons in the following six decay modes: pi+ pi- pi0 pi0, pi+ pi+ pi- pi- pi0, pi+ pi0 pi0, pi+ pi+ pi- pi0, eta pi0, and omega pi+ pi-. Improved branching fraction measurements in eight other multipion decay modes are also presented. The measured D --> pi pi rates allow us to extract the ratio of isospin amplitudes A(DeltaI = (3/2) / A(DeltaI = (1/2)) = 0.420 +/- 0.014(stat) +/- 0.016(syst) and the strong phase shift of delta1 = (86.4 +/- 2.8 +/- 3.3) degrees, which is quite large and now more precisely determined.  相似文献   
166.
167.
In this paper, we consider the multidimensional stability of planar waves for a class of nonlocal dispersal equation in $n$--dimensional space with time delay. We prove that all noncritical planar waves are exponentially stable in $L^{\infty}(\RR^n )$ in the form of $\ee^{-\mu_{\tau} t}$ for some constant $\mu_{\tau} =\mu(\tau)>0$( $\tau >0$ is the time delay) by using comparison principle and Fourier transform. It is also realized that, the effect of time delay essentially causes the decay rate of the solution slowly down. While, for the critical planar waves, we prove that they are asymptotically stable by establishing some estimates in weighted $L^1(\RR^n)$ space and $H^k(\RR^n) (k \geq [\frac{n+1}{2}])$ space.  相似文献   
168.
Editorial          下载免费PDF全文
After nearly a year of preparation, our journal, "Journal of Applied Analysis and Computations (JAAC)" is proud to announce the publication of its inaugural issue. During the preparation process, the Journal JAAC has been warmly supported by the President and other administrators of the Shanghai Normal University, our distinguished Editorial Board, and many fellow mathematicians. At this moment, we would like to thank all the supporters and express our heartfelt appreciation!  相似文献   
169.
Yangyang Ge 《中国物理 B》2022,31(4):48704-048704
Quantum singular value thresholding (QSVT) algorithm, as a core module of many mathematical models, seeks the singular values of a sparse and low rank matrix exceeding a threshold and their associated singular vectors. The existing all-qubit QSVT algorithm demands lots of ancillary qubits, remaining a huge challenge for realization on nearterm intermediate-scale quantum computers. In this paper, we propose a hybrid QSVT (HQSVT) algorithm utilizing both discrete variables (DVs) and continuous variables (CVs). In our algorithm, raw data vectors are encoded into a qubit system and the following data processing is fulfilled by hybrid quantum operations. Our algorithm requires O[log(MN)] qubits with O(1) qumodes and totally performs O(1) operations, which significantly reduces the space and runtime consumption.  相似文献   
170.
一种具有指数截断和局部集聚特性的网络模型   总被引:1,自引:0,他引:1       下载免费PDF全文
袁韶谦  Zhao Hai  李超  Zhang Xin 《物理学报》2008,57(8):4805-4811
针对真实网络局域演化的特点,提出了一种具有局部集聚特性的网络演化模型——局部集聚模型(LC模型). 理论分析和模拟实验表明,LC模型的节点度服从一种具有指数截断的幂律分布,同时它的平均聚类系数要远大于局域世界模型,接近真实网络. 模拟了LC模型对恶意攻击和随机错误的抵抗力,发现高聚类系数的LC模型对恶意攻击更加脆弱. 关键词: 局部集聚 指数截断 脆弱性 无标度网络  相似文献   
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