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171.
LU Shao-Fang HUANG Jian-Quan HUANG Xiao-Ying WU Qiang-JinState Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou Fujian China 《中国化学》1997,15(4):296-303
A new cluster compound {[Mo3(μ3-O)(μ-S)3(dtp)3(py)3][CdI(dtp)2]} (dtp=S2P(O-was obtained from the reaction of (Mo3OS3(dtp)4(H2O)] with a CdI2-Bu4NI mixture.The molecular structure is composed of a cluster cation [Mo3OS3(dtp)3(py)3]+ and the complex anion [CdI(dtp)2]-Crystal data:Triclinic,space group P1 with cell parameters a=1.4672(7),b=1.5356(5),c=1.6806(5) nm,α=74.59(3),β=67.89(4),7=78.86(3)°,V=3.364(2) nm3,and Z=2,least-squares refinement of 8941 reflections gives a final agreement factor of R=0.052,Rw=0.065. 相似文献
172.
XU Jing ZHENG ShouTian & YANG GuoYu State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou China 《中国科学B辑(英文版)》2011,(9)
Six novel 3D layer-pillared lanthanide-transition metal coordination polymers,LnCuX(IN)2(Ac)(H2O)(Ln = Tb,X = Br(1);Ln = Er,X = Cl(2)),[LnCuCl(IN)2(Ac)].H2O(Ln = Gd(3);Ln = Eu(4)),and [LnCu2Br2(IN)2(Ac)(H2O)].nH2O(Ln = Dy,n =0(5);Ln = Gd,n = 0.5(6))(IN = isonicotinate,Ac = acetate),have been obtained by linking Ln-organic layers and diverse Cu-complex pillars under hydrothermal conditions.1 and 2 are isostructural and formed by 2D Ln-IN-Ac layers and CuX(IN)2 pillars(X = Br(1),X= Cl(2));3 and 4 are isomorph... 相似文献
173.
微分方程dx/dt=Ax f(x)(其中A的特征根实部异于零)拓扑线性化的经典结论是由Hartman与 Grobman给出的,但是他们的结论都是局部拓扑线性化,即要求同胚函数限制在原点的小邻域内.如 果要延伸到全局上的话,必须f(x)有界.本文研究了系统(1.3),证明当此系统满足适当的条件时可全 局线性化. 相似文献
174.
严荣沐 《数学年刊A辑(中文版)》2005,(6)
本文讨论形式Generic流形上的型.利用加权坐标系先对齐权流形给出计算型的一般步骤并把结 果推广到一般的形式Generic流形. 相似文献
175.
The electrospray ionization mass spectrometry investigation showed that the binding sites of [ZnL]2+, where L is 2-[bis(2-aminoethyl)aminolethanol, with oxidized insulin B chain are Phe1, His5 and Arg22, which lead to the selective cleavages of the peptide bonds at Phe1-Val2, His5-Leu6, Glu21-Arg22, and Arg22-Gly23 of oxidized insulin B chain. 相似文献
176.
Xianjin Feng Fan Yang Feng Ji Fujian Zong Caina Luan Honglei Ma 《Applied Surface Science》2008,254(20):6601-6604
Antimony-doped tin oxide (SnO2:Sb) single crystalline films have been prepared on α-Al2O3 (0 0 0 1) substrates by metal organic chemical vapor deposition (MOCVD). The antimony doping was varied from 2% to 7% (atomic ratio). Post-deposition annealing of the SnO2:Sb films was carried out at 700-1100 °C for 30 min in atmosphere ambient. The effect of annealing on the structural, electrical and optical properties of the films was investigated in detail. All the SnO2:Sb films had good thermal stability under 900 °C, and the 5% Sb-doped SnO2 film exhibited the best opto-electrical properties. Annealed above 900 °C, the 7% Sb-doped SnO2 film still kept high thermal stability and showed good electrical and optical properties even at 1100 °C. 相似文献
177.
詹华税 《数学年刊A辑(中文版)》2006,(6)
对拟线性退化抛物方程θ_(xx)u uθ_yu-θ_tu=f(·,u)进行了研究,得到了在[O,T]×Ω上的初边值问题解的存在唯—性,这里要求T充分小. 相似文献
178.
The two title compounds obtained by solid state reaction at high temperature were char-acierized as isomorphism by single--crystal X--ray diffraction. The space group of both crys-tals is C_(2v)~4-Pma2, with lattice constants a = 7.955(1), b=6.258 (1), c=7 .203(2)A forI, and a =7.914 (1), b=6.237 (1), c=7.236 (1) ? for Ⅱ, Z=2. The structures were de-termined by normal method and refined to the final R = 0.074 and 0.083, respectively. Theresults show that the structure may be regarded as building by cluster unit with formulaNi_2M_2Te_4 (M =Nb or Ta) in which two Ni atoms and two M atoms form a rhombus, whilethe Te atoms are distorted tetrahedrally coordinated with both kinds of metal atoms. In thecluster unit there exist interactions between Ni atoms as well as between Ni and M atoms.In addition, all the cluster units are linked together not only by bridging Te atoms, but alsoby weaker metal-metal interactions, so as to form two--dimensional network. Therefore, thestructure may be represented by the for 相似文献
179.
本文介绍了火焰原子吸收光谱法测定含卤素金属原子簇化合物中银。研究了样品制备方法及常见共存元素干扰。平均回收率100%(99-101%),相对标准偏差<1%。用本法测定含卤素金属原子簇化合物中银,获得满意的结果。 相似文献
180.
CP-PEI-FA was prepared as an effective vector for in vitro and in vivo tumor-targeted gene delivery. The structures of the polymers were characterized, and their DNA condensation capability, particle sizes, zeta potentials, cytotoxicity and in vitro/in vivo transfection were examined. The cytotoxicity of CP-PEI-FA was significantly lower than that of PEI 25 kDa and close to that of PEI 1200. The in vitro transfection of CP-PEI-FA was tested in C6 and HeLa cells (FR-positive cells) and A549 cells (FR-negative cells). CP-PEI-FA showed a high targeting specificity and good gene transfection efficiency in FR-positive cells. These results indicate that CP-PEI-FA is a safe and effective polyplex-forming agent for both in vitro and in vivo transfection of plasmid DNA. 相似文献