Mn（Ⅱ）,Co（Ⅱ）与HSA相互作用的荧光光谱研究

用荧光光谱法研究了生理ｐＨ和等离子点（ｐＨ＝５．３０）时Ｍｎ（Ⅱ）、Ｃｏ（Ⅱ）与ＨＳＡ的相互作用。根据Ｆｏｒｓｔｅ非辐射能量转移理论,得到了不同ｐＨ时Ｍｎ（Ⅱ）、Ｃｏ（Ⅱ）在ＨＳＡ中的第一强结合位置与Ｔｒｐ－２１４残基间的距离。这一结果远大于文献报道值,根据Ｍｎ（Ⅱ）、Ｃｏ（Ⅱ）在ＨＳＡ中的结合部位及ＨＳＡ的畴结构对这一显著差异进行了讨论。     

3d＿（z￣2）基态铜（Ⅱ）冠醚配合物的粉末ESR谱

制备了两种不同基质的掺杂３ｄ＿（ｚ￣２）基态铜（Ⅱ）苯并１５冠５配合物（Ｃｕ（Ⅱ）Ｂ１５Ｃ５）的粉末样品，ＥＳＲ测定结果表明，以Ｂ１５Ｃ５为基质时，Ｃｕ（Ⅱ）Ｂ１５Ｃ５的轴向配体是Ｈ＿２Ｏ；而以Ｍｇ（Ⅱ）Ｂ１５Ｃ５为基质时的轴向配体则是．不同的轴向配体对ＥＳＲ谱的线型有着较大的影响。利用Ｂｌｅａｎｅｙ公式，计算了键参数，并对成键特性进行了讨论和比较。     

Ni（Ⅱ）,Cu（Ⅱ）,Zn（Ⅱ）的硝酸盐与氟哌酸的固态配合物的 …

由氟哌酸与Ｎｉ（Ⅱ）、Ｃｕ（Ⅱ）、Ｚｎ（Ⅱ）的硝酸盐合成了三个未见报道的固态配合物,并用元素分析、摩尔电导、红外光谱、热重分析表征了它们的组成和性质。     

拉曼光谱在医学上的应用（Ⅱ）

拉曼光谱在医学上的应用（Ⅱ）余国滔（北京大学生命科学学院北京１００８７１）ＢｉｏｍｅｄｉｃａｌＡｐｐｌｉｃａｔｉｏｎｓｏｆＲａｍａｎＳｐｅｃｔｒｏｓｃｏｐｙ（Ⅱ）ＹｕｅＫｗｏｋｔｏ（ＣｏｌｅｇｅｏｆＬｉｆｅＳｃｉｅｎｃｅｓ，ＰｅｋｉｎｇＵｎｉｖｅｒｓ...     

光谱法研究铜锌超氧歧化酶与组氨酸钴（Ⅱ）的相互作用：Ⅱ. …

采用ＶＩＳ和ＩＣＰ及酶活性测定等方法,研究铜锌超氧歧化酶（Ｃｕ２ＺｎＳＯＤ）与组氨酸钴（Ⅱ）〖Ｃｏ（Ｈｉｓ）〗的直接相互作用及外加组氨酸钴（Ⅱ）、磷酸盐对此类相互作用的影响。结果发现,水溶液中原酶活性中心Ｃｕ（Ⅱ）和Ｚｎ（Ⅱ）离子可被外加的组氨酸钴（Ⅱ）部分诱导,交换出来,而Ｃｏ（Ｈｉｓ）。中的Ｃｏ（Ⅱ）进入酶的活性中心,形成“Ｃｏ－ＳＯＤ”酶衍生物各组分,并相应影响了酶的催化活性。与此同时,外加     

Fe（Ⅲ）、Al（Ⅲ）、Ni（Ⅱ）非有机溶剂液－液萃取行为的研究

本文研究了ＰＥＧ（聚乙二醇）－２０００－钍试剂－（ＮＨ＿４）＿２ＳＯ＿４体系对Ｆｅ（Ⅲ）、Ａｌ（Ⅲ）、Ｎｉ（Ⅱ）的非有机溶剂萃取行为。指出在ｐＨ为３．５－６．５（ＮａＡｃ－ＨＡｃ）的水溶液中，有（ＮＨ＿４）＿２ＳＯ＿４存在下，Ｆｅ（Ⅲ）、Ａｌ（Ⅲ）可被ＰＥＧ－２０００相几乎完全萃取，而Ｎｉ（Ⅱ）则基本上不被萃取。从而获得了Ｎｉ（Ⅱ）与Ｆｅ（Ⅲ）、Ａｌ（Ⅲ）混合离子的定量分离。     

手性schiff碱金属配合物N,N‘—双水杨醛缩—1,2—环己二胺合镍（Ⅱ） …

利用经外、拉曼光谱研究一种手性ｓｃｈｉｆｆ碱金属配合物Ｎ,Ｎ’－双水杨醛缩－１,２－环己二胺合镍（Ⅱ）的结构特点。表明（Ｒ,Ｒ）－ＳＡＬＥＮ－Ｎｉ（Ⅱ）和（Ｓ,Ｓ）－ＳＡＬＥＮ－Ｎｉ（Ⅱ）的光谱完全相同,而与外消旋体的光普有很大差别。     

Pd（Ⅱ）苊醌缩氨基硫脲配合物的合成、表征及其与DNA的相互作用

合成了新型配合物Pd（Ⅱ）苊醌缩氨基硫脲,用元素分析、红外光谱、紫外光谱、核磁共振光谱和热分析对配合物进行了表征,并用荧光光谱研究了配体和配合物与DNA的相互作用。结果表明,配合物中配体以氧、氮和硫（ON S）三齿鳌合形式与金属离子配位,配合物与DNA的结合能力远大于配体。     

过渡金属Mn（Ⅲ）,Fe（Ⅲ）,Rh（Ⅱ）和Pd（Ⅱ）卟啉配合物的共振拉…

讨论了金属离子Ｍｎ（Ⅲ），Ｆｅ（Ⅲ），Ｒｈ（Ⅲ）和Ｐｄ（Ⅱ）原卟啉Ⅸ－二甲酯（ＰＰ）和四苯基卟啉（ＴＰＰ）配合物及Ｐｄ（Ⅱ）间氯四苯基卟啉（ＴＰＰｍ－ｃｌ）配合物的共振拉曼光谱。利用金属离子外层ｄ电子与卟啉环的作用，解释了配合物结构灵敏带的变化规律，同时讨论了不同卟啉及卟啉环上取代基团对结构灵敏带的影响。     

叶绿素a锰（Ⅲ）和叶绿素a锰（Ⅱ）的合成和光谱

叶绿素ａ锰（Ⅲ）（Ｍｎ（Ⅲ）－Ｃｈｌ－ａ）由脱镁叶绿素（Ｐｈｅｏ－ａ）和醋酸锰（Ⅱ）合成而得，用反相高效液相色谱法分离纯化，叶绿素ａ锰（Ⅱ）（Ｍｎ（Ⅱ）－Ｃｈｌ－ａ）用Ｎａ２Ｓ２Ｏ４还原时绿素ａ锰（Ⅲ）获得，研究了它们的元素分析（ＥＡ），紫外可见吸附光谱（ＵＶ－Ｖｉｓ）和傅里叶红外吸收光谱（ＦＴ－ＩＲ）证明了此二种配合物的合成，并给出了（Ｍｎ（Ⅲ）－Ｃｈｌ－ａ）与（Ｍｎ（Ⅱ）－Ｃｈｌ－ａ）的组成分     

过渡元素与氟哌酸根的固态配合物的制备与表征

由氟哌酸根与过渡金属Ｃｏ（Ⅱ）,Ｎｉ（Ⅱ）,Ｃｕ（Ⅱ）,Ｚｎ（Ⅱ）的氯化物合成了四个未见报道的固态配合物,并用元素分析、红外光谱,热分析表征了它们的组成和性质。     

The electronic structure of polymerized fullerenes and dimerized heterofullerenes

\chem{Rb_1C_{60}} and dimerised using electron energy-loss spectroscopy in transmission. From the excitation spectra a reduced density of states is observed for polymerized . This is in contrast to and can be explained by the different type of \squt{doping} and by the different bonding between the fullerene molecules in the two systems. Additional information about the optical properties was obtained from the low energy loss function. Using a Kramers-Kronig analysis, the dielectric function, (), and the optical conductivity, (), have been derived. and the onset of the spectral weight have been compared between the polymer, the dimer and . This onset of spectral weight is found to be at and for o- and for , respectively. Received: 28 October 1996/Accepted: 13 December 1996     

Anomalous temperature dependence of resistivity in quasi-one-dimensional conductors in a strong magnetic field

We present a heuristic, semiphenomenological model of the anomalous temperature (T) dependence of resistivity recently observed experimentally in the quasi-one-dimensional (Q1D) organic conductors of the family in moderately strong magnetic fields. We suggest that a Q1D conductor behaves like an insulator (), when its effective dimensionality is one, and like a metal (), when its effective dimensionality is greater than one. Applying a magnetic field reduces the effective dimensionality of the system and switches the temperature dependence of resistivity between the insulating and metallic laws depending on the magnitude and orientation of the magnetic field. We critically analyze whether various microscopic models suggested in literature can produce such a behavior and find that none of the models is fully satisfactory. In particular, we perform detailed analytical and numerical calculations within the scenario of magnetic-field-induced spin-density-wave precursor effect suggested by Gor'kov and find that the theoretical results do not agree with the experimental observations. Received 20 October 1998     

A computer simulation study of the ground-state configurations of Fe and Fe-Al clusters

Using the noncentral embedded atom model potential recently proposed by Besson and Morillo for bulk alloys (), we performed computer simulations to predict the ground-state configurations of and clusters (). The computed structures of clusters are in general agreement with such theoretical results as have been obtained by density functional calculations (i.e. for ). The results for Fe-rich clusters show surface segregation of Al, which is in keeping with the findings of a previous study of clusters. Received 29 April 1999     

A note on the screening of hydrodynamic interactions, in electrophoresis, and in porous media

We consider two situations where hydrodynamic interactions are said to be “screened”: hydrodynamics in a gel or in a porous medium, and electrophoresis in an electrolyte. We focus on the corresponding Green functions, and show that the flow fields are similar in the two cases. Contrarily to statements often made, the fluid velocity decays algebraically with distance (), i.e. not exponentially. We point out that the pressure fields are different in the two cases. Received 23 March 2000     

On measurement of helicity parameters in top quark decay

To enable an evaluation of future measurements of the helicity parameters for decay in regard to violation, this paper considers the effects of an additional pure-imaginary coupling, or , associated with a specific, single additional Lorentz structure, . Sizable violation signatures can occur for low-effective mass scales (), but in most cases can be more simply excluded by precision measurement of the probabilities and . Signatures for excluding the presence of violation associated with the two dynamical phase-type ambiguities are investigated. Received: 10 July 2000 / Published online: 8 September 2000     

Molecular order in bilayer,anticlinic and ferroelectric smectic C mesophases

In this work we present a proton NMR comparative study of the molecular order in the smectic C2 (), smectic C^* () and anticlinic smectic C phases ( and ) of two liquid crystalline compounds. The second moments of the experimental proton NMR spectra are well explained taking into account two different molecular orientations models. From the analysis of our experimental results it was possible to estimate the tilt angles for all the smectic C phases studied in this work. Received 15 September 1999 and Received in final form 18 January 2000     

顶超对称夸克“非汉字符号”与重夸克的束缚态质谱

基于实验尚未完全排除最轻的超对称夸克伴子———标量顶夸克 t1( t1)的寿命可相当长 ,以至在它产生后衰变之前有机会与通常夸克或胶子形成‘强子’的可能性的这一事实 ,建立了这一标量顶夸克 t1( t1)和另一重夸克Q( Q)组成的颜色单态束缚态 (c t1)和 (b t1) (以及它们反粒子相应的束缚态 )的贝特 -沙皮特方程 ,并借助瞬时近似求出了相应束缚态的质谱     

Substantiation of the two-temperature kinetic model by comparing calculations within the kinetic and fluid models of the positive column plasma of a dc oxygen discharge

Results from kinetic and fluid simulations of the positive column plasma of a dc oxygen discharge are compared using commercial CFDRC software (), which enables one to perform numerical simulations in an arbitrary 3D geometry with the use of both the fluid equations for all the components (fluid model) and the kinetic equation for the electron energy distribution function (kinetic model). It is shown that, for both the local and nonlocal regimes of the formation of the electron energy distribution function (EEDF), the non-Maxwellian EEDF can satisfactorily be approximated by two groups of electrons. This allows one to take into account kinetic effects within the conventional fluid model in the simplest way by using the proposed two-temperature approximation of the nonequilibrium and nonlocal EEDF (2T fluid model).     

Field-induced magnetic reorientation and effective anisotropy of a ferromagnetic monolayer within spin wave theory

The reorientation of the magnetization of a ferromagnetic monolayer is calculated with the help of many-body Green's function theory. This allows, in contrast to other spin wave theories, a satisfactory calculation of magnetic properties over the entire temperature range of interest since interactions between spin waves are taken into account. A Heisenberg Hamiltonian plus a second-order uniaxial single-ion anisotropy and an external magnetic field is treated by the Tyablikov (Random Phase Approximation: RPA) decoupling of the exchange interaction term and the Anderson-Callen decoupling of the anisotropy term. The orientation of the magnetization is determined by the spin components (), which are calculated with the help of the spectral theorem. The knowledge of the orientation angle allows a non-perturbative determination of the temperature dependence of the effective second-order anisotropy coefficient. Results for the Green's function theory are compared with those obtained with mean-field theory (MFT). We find significant differences between these approaches. Received 6 April 1999 and Received in final form 9 July 1999