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951.
李冰  吕雪飞  庆宏  邓玉林 《分析化学》2012,40(9):1336-1340
基于酶与底物间的相互作用,建立了蛋白-脂质体复合物毛细管电泳筛选单胺氧化酶(MAO)抑制剂的新方法.分别将不同浓度的4种N-炔丙基胺类化合物添加至含有蛋白-脂质体复合物的毛细管电泳缓冲液中,抑制MAO活性.考察MAO底物犬尿胺(Kyn)在含有不同浓度N-炔丙基胺类化合物缓冲液中的迁移时间比率(RMTR).结果表明,化合物N-炔丙基-N-甲基-R-2-庚胺(R-2-HMP)和N-炔丙基-R-2-庚胺(R-2-HPA)能够明显抑制MAO活性,导致MAO与Kyn的相互作用减弱,Kyn的RMTR值随着R-2-HMP和R-2-HPA的增加呈现出明显增加的趋势.化合物N,N-二炔丙基-R-2-己胺和N,N-二炔丙基-R-2-辛胺对MAO活性抑制不明显,Kyn的RMTR随这两种浓度增加变化不大.此结果与柱外孵育测定化合物活性结果一致.与传统MAO筛选剂筛选方法相比,本方法快速,成本低,酶消耗量少且不受分离电压等于扰因素的影响.  相似文献   
952.
A new coordination compound [Ba(OBPT)2(H2O)2]·H2O was obtained at room temperature by the reaction of 4,6-bis(2-pyridyl)-1,3,5-triazin-2-ol(HOBPT) with BaCl2.It was characterized by elemental analysis,FTIR,TG analysis,powder X-ray diffraction analysis and single-crystal X-ray diffraction analysis.The complex crystallizes in the monoclinic P21/n space group,with a = 16.325(1),b = 6.7977(5),c = 24.164(2) ,β = 104.009(1),V = 2601.8(3) 3,Z =4,C26H22BaN10O5,Mr = 691.88,Dc = 1.766 g/cm3,F(000) = 1376 and μ(MoKα) = 1.587 mm-1.The final R = 0.0282 and wR = 0.0724 for 5095 observed reflections with I > 2σ(I) and R = 0.0312 and wR = 0.0744 for all data.In the complex,the barium ion is ten-coordinated with six nitrogen atoms from two ligands,two deprotonated hydroxyl oxygen atoms from another two ligands and two coordinated water molecules to form a double stranded chain.The extensive supramolecular interac-tions lead to the formation of an infinite 2D framework.  相似文献   
953.
A novel type of Ti decorating benzene grafted tetrahydrido-silsequioxane struc-tures was designed and investigated using density functional theory(DFT).The hydrogen adsorption properties of this new material were investigated at the same level of theory.The results reveal that up to four hydrogen molecules(with the restrict of 18 electrons rule) can be adsorbed on each Ti atom of(TiC6H5)m-H4-mSi4O6(m = 1-4) molecular systems with the average binding energies of 0.691,0.692,0.693 and 0.695 eV for m = 1-4,respectively.The variations of HOMO- LUMO energy gaps verify that the host structures with four H2 molecules adsorbed own the best kinetics stability.The interaction mechanism of H2 molecules with the host materials mainly attributes to the well-known "kubas interactions".All the results indicate that the complex structures designed here may be used as hydrogen storage materials at ambient conditions.  相似文献   
954.
In this paper,we study some ergodic theorems of a class of linear systems of interacting diffusions,which is a parabolic Anderson model.First,under the assumption that the transition kernel a=(a(i,j)) i,j∈s is doubly stochastic,we obtain the long-time convergence to an invariant probability measure νh starting from a bounded a-harmonic function h based on self-duality property,and then we show the convergence to the invariant probability measure νh holds for a broad class of initial distributions.Second,if(a(i,j)) i,j∈S is transient and symmetric,and the diffusion parameter c remains below a threshold,we are able to determine the set of extremal invariant probability measures with finite second moment.Finally,in the case that the transition kernel(a(i,j)) i,j∈S is doubly stochastic and satisfies Case I(see Case I in [Shiga,T.:An interacting system in population genetics.J.Math.Kyoto Univ.,20,213-242(1980)]),we show that this parabolic Anderson model locally dies out independent of the diffusion parameter c.  相似文献   
955.
冯宏剑 《中国物理 B》2012,21(8):87103-087103
First-principals calculations show that magnetization reversal is accompanied by the opposite sense of rotation of the neighboring oxygen octahedra along the [1 1 1] direction which is called the antiferrodistortive displacement in BiCrO3. The coupling between magnetization and antiferrodistortive distortion is mainly caused by Dzyaloshinskii- Moriya interaction which is driven by the eg-eg states antiferromagnetic interaction in Cr-3d. A critical value of on-site Coulomb interaction prohibiting the Dzyaloshinskii-Moriya interaction and thus the magnetization reversal is found to be 1.3 eV.  相似文献   
956.
957.
I.  I.  Guseinov 《中国物理 B》2012,(6):137-140
The formulae are established in position,momentum,and four-dimensional spaces for the one-range addition theorems of generalized integer and noninteger μ Coulomb,and exponential type correlated interaction potentials with hyperbolic cosine(GCTCP and GETCP HC).These formulae are expressed in terms of one-range addition theorems of complete orthonormal sets of Ψα-exponential type orbitals(Ψ α-ETO),α-momentum space orbitals(α-MSO),and zα-hyperspherical harmonics(zα-HSH) introduced.The one-range addition theorems obtained can be useful in the electronic structure calculations of atoms and molecules when the GCTCP and GETCP HC in position,momentum,and four-dimensional spaces are employed.  相似文献   
958.
靳金玲  张向群  李国科  成昭华 《中国物理 B》2012,21(10):107501-107501
The Jahn-Teller distortion plays an important role in determining the exchange interaction in rare-earth manganites.In this work we study the influence of the Jahn-Teller distortion on the magnetic structures of TbMn1-xFexO3(x = 0,0.02,0.05,0.10,and 0.20) single crystals in the basal MnO2 plane.The decrease in the quadruple splitting with the increasing Fe doping indicates the reduction of the Jahn-Teller distortion,which makes the nearest neighboring(NN) FM interaction dominant over the next nearest neighbor(NNN) AFM interaction.This alteration is favorable for the development of A-type AFM ordering instead of the spiral magnetic ordering,which collapses when x ≥ 0.05.The analysis of dielectric data indicates that the ferroelectricity is arising from the peculiar spiral magnetic ordering.  相似文献   
959.
饱和粘弹性土层中悬浮桩的纵向振动   总被引:2,自引:0,他引:2  
基于不可压饱和粘弹性多孔介质理论和一维杆件模型,利用虚拟土桩的概念,研究了不可缮压饱和粘弹性土层中悬浮桩纵向振动的动力刚度.通过势函数解耦和三角级数解法,得到了悬浮桩纵向谐调振动的半解析解和桩头动力刚度.在此基础上通过数值计算,研究了物性参数、几何参数等对刚度的影响,结果表明:悬浮桩纵向振动的动力刚度受桩长、土的软硬程度、激振频率等的影响,对比了细长桩和短粗桩的响应差异,这些结果可为悬浮桩-土相互作用的数值分析和工程设计提供参考.  相似文献   
960.
荧光光谱法研究酸性大红3R与牛血清白蛋白的结合作用   总被引:1,自引:1,他引:0  
在Tris缓冲溶液(pH 7.4)体系中,运用荧光光谱法和紫外光谱法首次研究了染料酸性大红3R(AS)与牛血清白蛋白(BSA)的相互作用,并考察了表面活性剂对体系荧光强度的影响。结果表明,酸性大红3R与牛血清白蛋白能形成基态复合物,从而导致BSA内源荧光猝灭,猝灭机理主要涉及静态猝灭和非  相似文献   
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