二阶非线性光学活性分子——咪唑类衍生物的设计与性质的理论研究

采用B3LYP方法在6-31G*水平上优化了6种F,Cl和Br取代的咪唑类衍生物分子几何构型,在此基础上采用TD-DFT的方法计算了它们的前线轨道能级和电子光谱,并用CPHF方法研究了此类衍生物二阶非线性光学系数性质.计算结果表明:此类化合物具有平面结构,共轭性较强;分子内设计的推拉电子基团增强分子内电荷转移,使前线分子轨道间的电子跃迁更容易;各体系具有较大的vβec和良好的透明性;咪唑环的引入增强了体系的热稳定性.这些结论对分子设计具有一定的指导意义.     

一种共聚焦激光诱导荧光检测器的研制

 基于共聚焦检测，研制了一台便携式激光诱导荧光检测器。该系统具有体积小、重量轻、成本低等特点；成像观察校准系统使日常校准非常简单。采用毛细管电泳和流动注射方式对该体系性能进行了评价，以Cy5染料与Cy5标记的色氨酸作为检测物质，其检测下限为3.7 nmol/L。     

Study on Rapid Determination of Aristolochic Acids in Aristolochia Medicinal Plants

Aristolochic acid (AA) composed of AA-Ⅰ and AA-Ⅱ (Fig. 1 ) is the major toxic component extracted from Aristolochia plants. Recently, it has been proved by several researches that high doses of aristolochic acids (AA) can result in a severe kidney disease named Chinese herbs ne-     

一类含硅亚苯结构的新有机硅预聚体

一类含硅亚苯结构的新有机硅预聚体车波王安锋周彩华傅辛福林思聪（南京大学高分子科学与工程系生物材料分子工程和控制释放分子工程室南京２１００９３）关键词有机硅预聚体，对 硅亚苯硅氧烷，热稳定性，合成与表征，开环共聚从分子工程的角度看，以聚有机...     

Shiff碱茚(1,2-b)喹喔啉-11-酮缩氨基硫脲合钴髤配合物的合成、表征与晶体结构

0引言腙类Schiff碱及其配合物,由于具有光、电、磁性质和一定的抗菌、抗癌等生理活性作用一直是人们关注的热点[1￣3]。其中缩氨基硫脲Schiff碱及其配合物由于其不仅是性能优良的有机显色剂,而且还具有抗菌、抗病毒等生物活性,同时也是研究生物催化作用的模版,因而被广泛研究[4]。茚(1,2鄄b)喹喔啉鄄11鄄酮衍生物是一类重要的含N杂环,最近的研究显示其具有一些相当有趣的性质[5],然而有关其合成Schiff碱的研究很少,迄今为止,相关文献只有3例[6￣8],并且未见任何单体或配合物的单晶结构报道。此外,目前的Schiff碱结构中,大多是从芳环外羰基…     

SU(n,1)/S(U(n)×U(1))上的中心极限定理

Let G=SU(n,1),K=S(U(n)×u(1)),and for l∈Z,let{η)1∈Z be a one-Dimensional K-type and let E1 be the line bundle over G/K associated to η.In this work we obtain a central limit theorem for the space El.     

High Spin Band Structure in ^112Ru

Levels in the neutron-rich ^112Ru nucleus have been investigated by observing prompt gamma-rays from the spontaneous fission of ^252Cf with the Gammasphere detector array. The ground state band and the one-phonon γ-vibrational band have been confirmed and extended with spin up to 16h and 15h, respectively. The other two side bands, one proposed as two-phonon γ-vibrational band and the other proposed as two-quasiparticle band, have been observed for the first time. The total-Routhian-surface calculations show that rotational 112 Ru nucleus has triaxial deformation with parameters β2 - 0.27 and γ= -29°. The observed band crossing in the yrast band is due to the alignment of a pair of h11/2 neutrons according to the cranked shell model calculations. The possible configuration for the quasiparticle band has also been discussed.     

Molecular Imprinting Fibrous Membranes of Poly（ acrylonitrile-co-acrylic acid） Prepared by Electrospinning

Introduction Overthepastfewdecades,molecularimprinting hasbeendescribedasatechnologyforpreparing“mo leculardoors”whichcanbematchedto“template keys”.Ithasbeenfoundtobeasimpleandeffective approachtointroducespecificrecognitionsitesintosyn theticpolymers…     

A note on vortex solutions of Landau–Lifshitz equation

In this short note, by using the ideas of shooting method, we show that there exists no finite energy vortex solution to the Landau–Lifshitz equation without anisotropy for prescribed boundary values. Based on comparisons between the present result and the previous ones, we see that the isotropic terms play an important role in Landau–Lifshitz equation. Copyright © 2009 John Wiley & Sons, Ltd.     

气液两相流中的声速研究

气液两相流在工业各领域中广泛存在,而声速是描述其声学性质的一个重要参数。本文从流体的体积弹性模量的定义出发,推导了气液两相流中的声速随含气率的变化关系式,即混合流体的Wood声速公式,将其声速的部分计算结果和其他作者的实验数据进行了比较,吻合良好。并通过COMSOL有限元模拟软件得到不同气体分布下圆管谐振腔最低阶模式的共振频率,间接数值模拟研究了含气率对声速的影响。模拟结果与理论计算结果一致,当气液两相流中含气率较低时,声速随含气率的增大急剧减小。本研究结果为确定声速与气液两相流中的含气率间的关系提供了参考依据。