不同构象铂(Ⅱ)配合物与G-肌动蛋白作用的光谱研究

The cyclohexamethylene-diamine squaric acid platinum(Ⅱ) complexs(R,R, S,S) binding to G-actin and the consquence conformation change were studied by N-(1-pyrenyl) maleimide(NPM) labeled fluorescence and intrinsic fluorescence. The binding and chemical kinetics were determined by fluorometry. The results showed that when R (Pt/actin molar ratio) was lower than 30, the Pt binded to G-actin strong binding sites(-SH), when R was larger than 30, the Pt binded to G-actin weaker binding sites. The consquence conformation changes were determined by CD. The CD results showed that R was smaller than 60, G-actin α-helix contents decreased slowly, R was larger than 60, G-actin conformation changed obviously. The reaction of R,R complex of platinum(Ⅱ) S,S complex of platinum(Ⅱ) with G-actin was similar to that of with S,S complex of platinum(Ⅱ).     

(1R,3R)-1-氨基-1,3-二羧基环丁烷衍生物桥联环糊精与一组低分子量多肽之间的包合行为

The interactions between several peptides with low molecular weight (guest, NH₂-Arg-Arg-Trp-Trp-H 2; NH₂-Arg-Trp-Arg-Trp-H 3; NH₂-Trp-Arg-Arg-Trp-H 4; NH₂-Arg-Arg-Trp-Trp-Trp-Trp-H 5; NH₂-Trp-Trp-Arg-Arg- Trp-Trp-H 6; NH₂-Arg-Arg-Trp-Trp-Trp-Trp-Trp-Trp-H 7; NH₂-Arg-Arg-Trp-Trp-Trp-Trp-Trp-Trp-Trp-Trp-H 8) and β-cyclodextrin dimer (host, 1) bridged with the derivative of (1R, 3R)-1-aminocyclobutane-cis-1,3-dicar- boxylic acid were investigated by using fluorescence polarization method in buffer aqueous solution (pH 7.4) at 298K. The binding constants of the cyclodextrin dimer 1 to the guests 2-8 were determined. It was shown that there was a cooperative action of the two cavities of a cyclodextrin dimer in the binding of large substrates, and that the structure and properties of amino acid in the peptides played very important roles in the synergic complexation between host and guest.     

手性双核Salen配合物的合成与谱学性质

Six novel chiral dinuclear Salen complexes [Cu₂L₁·H₂O (3a), Cu₂L₂(3b), Ni₂L₁·2H₂O (4a), Ni₂L₂(4b), Mn₂Cl₂L₁·H₂O (5a), Mn₂Cl₂L₂ (5b)] have been synthesized(L₁ and L₂ are chiral dimeric Salen ligands with different chain length which were synthesized from (R,R)-diaminocyclohexane, salicylaldehyde, 4,4′-(1,10-decaneoxy)salicylaldehyde, 4,4′-(1,6-hexyloxy)salicylaldehyde). These compounds were charactered by elemental analysis, ¹H NMR, FT-IR, UV-Vis and CD spectra. The FT-IR, UV-Vis and CD spectra were discussed and compared with those of monomeric ligand and complex in detail. It was found that the spectra properties of compounds of different chain length were almost alike, and the properties of dimeric and monomeric compound were similar too. Furthermore Cotton effect and Cotton split of CD spectra of these chiral compounds were explained by the exciton interaction theory. It seemed that the direction of Cotton split depend on the configuration of diaminohexane. (R,R)-diaminohexane determine the chirality of Salen compounds as negative, and the positive and negative component of Cotton split lie at higher and lower energy respectively.     

Cu[C5H3N(CCH3=N-C6H5)2]2(PF6)2配合物的合成、晶体结构和热分解反应动力学

The title complex Cu[C₅H₃N(CCH₃=N-C₆H₅)₂]₂(PF₆)₂ has been synthesized by reaction of Schiff base C₅H₃N(CCH₃=N-C₆H₅)₂ and cupric sulfate in toluene solution. The crystal structure was determined by X-ray diffraction method and the chemical formula weight of the complex is 1041.85. The crystal structure belongs to triclinic system with space group P1 and cell parameters: a=12.6470(10)?, b=14.123(2)?, c=15.613(2)?;α=66.150(10)°,β=79.470(10)°,γ=78.290(10)°, V=2481.6(5)?³, Z=2, D_c=1.394Mg·m^-3 and F(000)=1064. The final R[I >2σ(I)]:R₁=0.0668, wR₂=0.1927; R(all data): R₁=0.1133, wR₂=0.2357. The Cu(Ⅱ) was coordinated by six nitrogen, at the same time the Cu(Ⅱ) formed a distorted octahedron, besides the angles and planes of this compound were discussed . The result of kinetics of the thermal decomposition indicated that the first step of it is 2 series chemical reactions, the function of machanism is f(a)=(1-a)², and the activation energy is 144.64E/kJ. CCDC: 180872.     

金(Ⅲ)与杯[4]乙酯合钠(Ⅰ)超分子化合物: [Na(C60H80O12)]+[Au(SCN)4]-的合成、结构及性能

A novel super molecule [Na(C₆₀H₈₀O₁₂)]⁺[Au(SCN)₄]^- was obtained by extraction of calix[4] arene (L) for an aqueous solution containing [AuCl₄]^-, and NaCl into CH₂Cl₂. The crystal structure and properties of the title super molecule were characterized by single-crystal X-ray diffraction, IR and ¹H NMR spectra. The X-ray single crystal structure analysis shows that the crystal was Tetragonal system with space group P4/n and the unit cell parameters were as follows: a=2.880 8(18) nm, b=2.880 8(18) nm, c=2.292 4(5) nm, and final R indices [I>2σ(I)]: R₁=0.048 5, wR₂=0.106 1. CCDC: 243229.     

[Zn(DMF)6]H2SiW12O40·(CH3)2NH的合成,晶体结构及性质

The title compound [Zn(DMF)₆]H₂SiW₁₂O₄₀·(CH₃)₂NH was synthesized in mixed solvent of aqueous and acetonitrile, and its crystal structure had been determined using single crystal X-ray diffraction. The crystal belongs to monoclinic, space group C2/m, a=2.0654(4)nm, b=1.3306(3)nm, c=1.3194(3)nm, β=119.59(3)°, V=3.1531(11)nm³, D_c=3.606Mg·m^-3, Z=2, R=0.0462, R_w=0.0836. The title compound comprises of a [Zn(DMF)₆]²⁺ unit, a polyanion and a free (CH₃)₂NH molecule. The ESR spectrum of the title compound shows that charge-transfer between organic groups and polyanion takes place under irradiation of the sunlight in solid state. The TG study of the title compound shows that it had four stages of the weight loss, and the increase of the de-composition temperature for the polyanion shows that the stability of the polyanion was enhanced due to the influence of Zn²⁺ ion. CCDC:175866.     

ZrW0.8Mo1.2O8立方相和正交相的微波合成及其表征

Both the cubic and orthorhombic ZrW_0.8Mo_1.2O₈ were prepared by precursor-microwave route. The cubic phase belonged to β-ZrW₂O₈ structure type and the orthorhombic phase was refined with the structural model of LT- ZrMo₂O₈ by the Rietveld method. The orthorhombic phase belonged to Pmn2₁ space group and the cell parameters were a_o=0.597 1(9) nm, b_o=0.730 6(1) nm, c_o=0.912 7(1) nm, R_p%=9.37; wR_p%=11.81. The TEM images were also given. The comparison was made between precursor-heated and precursor-microwave routes. Metastable polymorphic phase was favorably formed by the latter method.     

反相微乳液法合成SrTiO3纳米棒

SrTiO₃ nanorods were synthesized in cetanyl trimethyl ammonium bromide (CTAB) reverse microemulsion containing CTAB, n-hexanol, n-octane and water with Ba(OH)₂ as reactants. The effects of different conditions such as ω₀ [ω₀=n_H2O/ n_CTAB], aging time and the concentration of reactants on the formation of the nanorods were studied. Transmission electron microscope (TEM), electron diffraction (ED) and X-ray diffraction(XRD)were used to characterize the morphology and the structure of the synthesized nanorods. The results show that SrTiO₃ nanorods with a length of 260～2 000 nm and a diameter of 50～100 nm belonging to single crystal are single cubic system. The molar ratio of Sr to Ti of products is 1.0 as determinded by ICP.     

N-亚水杨基苄胺过渡金属配合物的合成、结构与抑菌性能研究(英)

N-salicylidene-benzylamineato M(Ⅱ) complexes (ZnL₂, CuL₂ and CdL₂) were synthesized, characterized and valued for antimicrobial activities against bacterial strands using the agar diffusion method. The crystal of ZnL₂ was determined by X-ray diffraction. It crystallizes in the Monoclinic system, space group C2/c with a=2.269 1(3), b=0.918 2(1), c=1.239 5(2) nm, β=117.89(2), Z=4, R₁=0.049 4, wR₂=0.138 2. The complexes were found to be active against Staphylococcus aureus and Eschierichia Coli. CCDC: 249474.     

CH2(COO)2Cu·2H2O热分解的非等温动力学研究

The thermal dehydration and decomposition kinetics of CH₂(COO)₂Cu·2H₂O were investigated using the non-isothermal method by thermogravimetry (TG) technique in N₂. The iterative iso-conversional methods were applied to calculate the activation energy E_a of dehydration and decomposition， and the most probable mechanism function G(α) was determined by means of the master plots method. The pre-exponential factor A was obtained on the basis of E_a and G(α). Kinetic parameters (E_a and lnA) of dehydration were given as: E_a=139.79 kJ·mol^-1， ln(A/s^-1)=47.38. The mechanism function of the dehydration was G(α)=[-ln(1-α)]^2/3， and the decomposition of CH₂(COO)₂Cu proceeds to completion by two distinct reactions. These two reactions overlap in the transition process (0.45<α<0.65). Kinetic parameters (E_a and lnA )of the first reaction of decomposition were: E_a=201.15 kJ·mol^-1， ln(A/s^-1)=52.29， and the mechanism function was G(α)=[1-α]^-0.37. And in the second reaction G(α)=α+(1-α)ln(1-α)， E_a=156.74 kJ·mol^-1， ln(A/s^-1)=39.58.     

离子液体中离子型共聚高分子保护的铂纳米粒子催化剂催化肉桂醛选择性加氢

用离子型共聚高分子poly(NVP-co-VBIM Cl-)保护离子液体[bmim]BF4中的铂纳米粒子.以肉桂醛选择性加氢制肉桂醇反应来评价铂纳米粒子的催化活性.结果表明,该体系下得到的铂纳米粒子粒径分布均一,并具有很高的稳定性.在离子液体中,此种高分子保护的铂纳米粒子对肉桂醛加氢制肉桂醇表现出良好的活性(转化率>90%)和选择性(>95%).催化剂可多次循环,其活性和选择性均能良好保持.     

透光导电金属及氧化铂半导体薄膜的制备与表征

通过PPh~3对“非保护型”铂金属纳米簇进行表面修饰,并将其萃取至甲苯中,制备的PPh~3修饰的Pt金属钠米簇于空气中可自发地在玻璃表面生长出均匀透光的金属钠米簇薄膜。该金属钠米簇薄膜经空气中加热处理后可转化为透光导电的氧化铂半导体薄膜。考察了金属钠米簇薄膜生长过程中UV-vis吸收光谱的变化。采用SEM和TEM等方法,表征了纳米簇的粒径及膜的多孔结构,由此解释了其透光原因。研究了薄膜的导电性与处理条件的关系,并采用XPS表征了处理过程中的物质变化。初步探索了PPh~3-Pt纳米簇自发成膜过程的机理,确定了氧气在此过程中的重要作用。     

苯乙烯-丁二烯-苯乙烯嵌段共聚物负载Pt催化肉桂醛制备肉桂醇的研究

用紫外光交联的方法制备不同交联度的苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)负载Pt的催化膜并探讨其对肉桂醛选择性加氢制备肉桂醇的催化效果.其中催化剂Pt纳米簇用微波法制备,XRD测其平均粒径为3.7 nm.膜载催化剂的负载量、光交联剂三羟甲基丙烷三丙烯酸酯(TMPTA)和光引发剂二苯甲酮(BP)的用量均为3%.用色谱-质谱联用、XRD、紫外分光光度计对膜载催化剂和反应产物进行了表征,结果表明,随着交联度的增加,肉桂醇的催化选择性先增后减,紫外光光照80s时,负载膜交联度23.63%,肉桂醛转化率为91.46,肉桂醇选择性80.98%.质谱分析表明交联度大于30%后,催化产物中开始有膜分解产生的小分子杂质出现,并随交联度的进一步增大而增多;显微镜检测同时说明此时膜结构发生变化,造成肉桂醇选择性的降低.     

Morphology of platinum electrodeposits in the three-dimensional sublayer to full layer range produced under different potential modulations on highly oriented pyrolytic graphite

The topography of platinum electrodes produced by electrodeposition (19 to 200 mC cm-2) on highly oriented pyrolytic graphite (HOPG) under different potential modulations was investigated by atomic force microscopy, scanning tunneling microscopy, and H-atom electrosorption voltammetry. To modulate electrodeposition, (i) triangular potential cycling at 0.1 V s-1, (ii) a linear cathodic potential at 0.1 V s-1 and anodic potential step cycling, and (iii) square wave potential cycling at 5000 Hz were utilized. AFM and STM imaging showed that at lower platinum loading the HOPG surface was partially covered by a 3D sublayer of platinum. Electrodes produced by procedure (i) were made of faceted platinum aggregates of about 200 nm and nanoclusters in the range of 5-20 nm; those that resulted from procedure (ii) consisted of anisotropic aggregates of nanoclusters arranged as quasi-parallel domains. These electrodes from (i) and (ii) behaved as fractal objects. The electrodes resulting from procedure (iii) exhibited a flat surface that behaved as a Euclidean object. For all WEs, as the platinum loading was increased the HOPG surface was fully covered by a thin 3D layer of platinum aggregates produced by electrodeposition and coalescence phenomena. Large platinum loading led to electrodes with fractal geometry. Statistical parameters (root-mean-square height, skewedness, kurtosis, anisotropy, Abbot curve, number of protrusions and valleys, and fractal dimension) were obtained from the analysis of AFM and STM imaging data. Platinum electrodeposition coupled to either H-adatom formation for procedures (i) and (ii) or phonon dispersion for (iii) was involved in the surface atom rearrangements related to electrofaceting. The H-adatom electrosorption voltammetry data were used to evaluate the real electrode surface area via the voltammetric charge and to advance a tentative explanation of the contribution of the different crystallographic facets to the global electrochemical process dominated by weak H-Pt adsorption interactions.     

基于硫化镉纳米团簇标记DNA电化学传感的研究

合成了表面具有自由羧基的硫化镉纳米团簇，以乙基-（3-二甲基丙基）碳二 亚胺盐酸盐为偶联活化剂，将其标记于人工合成的5'端氨基修饰的寡聚核苷酸片段 上，制备成CdS纳米团簇标记DNA探针，该寡聚核苷酸片段与大肠杆菌肠毒素基因相 关。在一定的条件下，使基与固定晨玻碳电极表面的待测DNA序列进行杂交反应， 利用阳极溶出示差脉冲伏安法（ASDPV）间接测定Cd的量，实现对互补、非互补 DNA片段的识别和电化学检测，从而对大肠杆菌肠毒素基因片段识别和检测。     

“非保护型”金属胶体纳米簇形成机理研究

碱-乙二醇法制备的"非保护型"金属及合金纳米簇由表面吸附的溶剂分子和简单离子实现稳定化,它们被广泛用于制备高性能复相催化剂和研究复相催化剂中的尺寸、组成、载体表面基团以及修饰剂对催化性能的影响。关于此类非保护金属纳米簇的形成过程及机理的认识尚有待进一步深化。本文采用原位快速扫描X射线吸收精细结构谱(QXAFS)、原位紫外-可见(UV-Vis)吸收光谱、透射电子显微镜和动态光散射技术研究了碱-乙二醇法合成中非保护型金属胶体纳米簇的形成过程与机理。结果表明,在碱-乙二醇法合成非保护型Pt金属纳米簇的过程中,室温下即有部分Pt(IV)被还原至Pt(II)。随着反应温度的升高,OH-逐渐取代与Pt离子配位的Cl-,在Pt―Pt键形成之前,反应体系的UV-Vis吸收光谱中可观察到明显的纳米粒子的散射信号,原位QXAFS分析表明Pt纳米簇是由Pt氧化物纳米粒子还原所形成的;在Ru金属纳米簇的形成过程中,OH-首先取代了Ru Cl_3中的Cl~-,形成羟基配合物Ru(OH) _6~(3-),后者进一步缩合形成氧化钌纳米粒子,最终Ru金属纳米簇由乙二醇还原氧化钌纳米粒子形成。由于先形成了氧化物纳米粒子,后续的还原反应被限制在氧化物纳米粒子内,使最终得到的非保护型金属纳米簇具有尺寸小、分布窄的特点。本工作所获得的知识对发展高性能能源转化催化剂、精细化学合成催化剂、传感器等功能体系具有重要意义。     

Pt-Au合金团簇热力学性质分子动力学模拟研究

采用分子动力学方法和原子嵌入法模型势模拟了Pt原子和Au原子合金纳米团簇的熔化过程,研究了这些金属原子纳米团簇熔点与团簇组分的关系,发现不同组分纳米团簇的熔点不是单调变化的,同时均出现了负热容现象.通过对各种团簇溶化前后结构的比较研究,分析了导致这种现象的原因.     

Novel application of Ag nanoclusters in fluorescent imaging of human serum proteins after native polyacrylamide gel electrophoresis (PAGE)

We have developed a novel application for DNA oligonucleotide-stabilized Ag nanoclusters in fluorescent imaging of human serum proteins after native polyacrylamide gel electrophoresis (PAGE). Oligonucleotide-stabilized Ag nanoclusters were used as fluorescent probes for direct detection of proteins after native PAGE. Some relatively low-abundance proteins, such as α-1-antichymotrypsin (ACT) and α-2-glycoprotein 1, zinc (ZAG) were easily detected by oligonucleotide-stabilized Ag nanocluster-based fluorescent imaging and identified by MS and MS/MS techniques, without the need of expensive antibodies or tedious immunoassay procedures. The pH condition for the oligonucleotide-stabilized Ag nanocluster solution was optimized and the possible mechanism of interaction between proteins and DNA oligonucleotide-stabilized Ag nanoclusters was analyzed. As a novel fluorescent detection method it is simple, fast, nontoxic and sensitive, and it shows great analytical potential in proteome research and in biochemistry.     

聚胸腺嘧啶单链DNA-CuNCs荧光增强法用于汞离子的高灵敏检测

基于Hg~(2+)与DNA中胸腺嘧啶(T)结合的高度特异性和DNA铜纳米簇的荧光增强性质,构建了一种简便、灵敏检测汞离子的新方法.当Hg~(2+)存在时,聚T单链DNA(P1)通过T-Hg~(2+)-T特异性结合形成双链DNA,Cu~(2+)经抗坏血酸钠还原后生成的中间体Cu+与双链DNA螺旋结构间的氢键部分有强的结合力,促使Cu0附着聚集在双链DNA上形成铜纳米簇,导致体系荧光增强,从而实现对汞离子的高灵敏检测.体系荧光强度与Hg~(2+)浓度的对数值成正比,对Hg~(2+)检测的线性范围为1.0 nmol/L~10μmol/L,检出限达0.4 nmol/L,对湖水样品中Hg~(2+)检测的回收率达到97.2%~106.6%.与传统方法相比,该方法具有无需标记、检出限低及选择性好等优点,可用于环境水体中汞离子的测定.     

High Selective Hydrogenation of Acetophenone Catalyzed by Alumina Supported platinum Nanoclusters

A new preparation and reduction method of γ-Al2O3 supported and PVP stabilized platinuzn nanoclusters was studied.The catalyst exhibited very high very high activity and selectivity for acetophenone hydrogenation in isopropanol-KOH solution at 25-60℃ and PH2=1-5 MPa.