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31.
复色光干涉实验两则郎秀娥,张淑华,冯国平(河北省张家口市卫校)(河北省唐山市丰南二中)(河北省张家口市十中)在没有激光光源的学校,光的干涉实验常用的演示装置由于光源功率小往往需要借助于目镜、显微镜等助视仪器观察干涉条纹,不能让许多人同时观察.笔者用白...  相似文献   
32.
张淑华  蒋毅民  肖瑜 《无机化学学报》2003,19(12):1339-1342
A heteronuclear compound, K2[Co(Dipc)2]·7H2O (Dipc=pyridine-2,6-dicarboxylic acid) has been synthe- sized and characterized by IR, elemental analysis, and X-ray diffraction. Crystal data: orthorhombic system with space group Pnna and unite cell parameters: a=2.0645(3)nm, b=1.3484(2)nm, c=0.8204(1)nm; V=2.2838(6)nm3, Z=4, Dcald=1.726 g·cm-3, μ=1.193 mm-1, F(000)=1212, Gof=1.045, Δρ=339~-348 e·nm-3, the final R is 0.0295. In the molecule of the complex, Co(Ⅱ) ion is six-coordinate to form a dis-torted octahedron. The N atom and the carboxyl group of pyridine-2,6-dicarboxylic acid are coordinated with the central ions. One of the carboxyl groups of the pyridine-2,6-dicarboxylic acid connect K(Ⅰ) and Co(Ⅱ). The com- pound possesses approximate C2 symmetry. The compounds form a three-dimensional network of infinite length connection with crystal waters, potassium ions and hydrogen bonds. The result of kinetics of thermal decomposition indicated that the compound decomposition takes place in two steps. CCDC: 207078.  相似文献   
33.
The title complex was synthesized by reaction of taurine salicylic schiff base(TSSB), O-phenanthroline(phen) and cupric acetate in water-ethanol solution. The crystal structure was determined by X-ray diffraction method and the chemical formula weight of the complex is 498.00. The crystal structure of the title complex belongs to orthorhombic system with space group Pbcn and cell parameters: a=3.107 2(4) nm, b=1.289 09(18) nm, c= 1.034 78(14) nm; and V=4.144 7(10) nm3, Z=8, Dc=1.596 g·cm-3, μ=1.197 mm-1, F(000)=2 048. The compound is an one-dimensional chain complex of infinite length which are connected with hydrogen bonds. The Cu(Ⅱ) was coordinated by two oxygen atoms and three nitrogen while the o atoms of Ac- groups did not participate in the coordination. The Cu(Ⅱ) formed a distorted tetragonal pyramid and the capacities of coordination to Cu(Ⅱ) of atoms was discussed. Besides, the TG-IR of the complex was analyzed. The kinetics of the thermal decomposition reaction of the complex was studied under a non isothermal condition by TG-IR. TG and DTG curves indicate that the complex decomposed in three stages: (?) The kinetic parameters were obtained from the analysis of TG,DTG cures by OZAWA-Flynn-Wall method, and the activation energy and the value of A of the three stages are 74.98 kJ·mol-1, 286.65 kJ·mol-1, 87.55 kJ·mol-1; 9.66×108 s-1,1.82×1028 s-1, 3.09×103s-1, respectively.  相似文献   
34.
合成了标题化合物。该化合物的分子式[Ni(C5H5N)2(C7H6O2N)2]H2O(C24H24N4NiO3),分子量475.18,采用单色的MoKα (λ = 0.71073 )射线测定,共收集7408个数据,其中独立衍射点2567个(Rint = 0.0272),I > 2s(I)可观测点数1926个,结果表明该化合物属单斜晶系, 空间群C2/c其晶胞参数为: a = 14.466(2),b = 12.193(2),c = 14.072(2) ;β = 116.229(2)°,V = 2226.6(5) 3,Z = 4,Dc = 1.418 g/cm3 ,μ = 0.905 mm-1,F(000) = 992. 2个水杨醛亚胺各提供2个配位原子参与配位,2个吡啶各提供1个配位原子参与配位,该配合物是六配位的八面体构型,同时讨论了该体系中不同配位原子的配位能力的差异。  相似文献   
35.
柳福提  张淑华  程艳  陈向荣  程晓洪 《物理学报》2016,65(10):106201-106201
本文利用密度泛函理论结合非平衡格林函数的方法, 对 (GaAs)n(n=1-4)直线原子链与Au(100)-3×3两半无限电极耦合构成Au-(GaAs)n-Au纳米结点的电子输运性质进行了第一性原理计算. 在各结点拉伸过程中, 对其结构进行了优化, 得到各结点稳定平衡结构时Ga-As的平均键长分别为0.220, 0.224, 0.223, 0.223 nm, 平衡电导分别为2.328G0, 1.167G0, 0.639G0, 1.237G0; 通过对结点投影态密度的计算, 发现电子传输主要是通过Ga, As原子中px与py电子轨道相互作用形成的π键进行的. 在0-2 V的电压范围内, 对于(GaAs)n(n=1-3)的原子链的电流随电压增大而增大, I-V曲线呈线性关系, 表现出类似金属导电行为; 对于(GaAs)4原子链在0.6-0.7 V, 0.8-0.9 V的电压范围内却存在负微分电阻现象.  相似文献   
36.
以4-氟水杨酸(H2foac)和2,2'-联吡啶(bipy)为原料,甲醇和水为溶剂,醋酸铜为离子源,采用溶剂热法合成了一个新型的双核铜配合物{[Cu2(foac)2(bipy)2]·3H2O(1)},其结构和荧光性能经IR,FL,元素分析和X-射线单晶衍射表征。1属三斜晶系,Pī空间群,晶胞参数a=8.198(2),b=9.986(3),c=11.814(4),α=91.45(3)°,β=105.78(2)°,γ=92.87(3)°,V=928.8(5)3,Z=1,Dc=1.433 g·cm-3,μ=1.210mm-1,F(000)=408。1中两个Cu(Ⅱ)分别与bipy的两个氮原子,foac2-的两个氧原子及另一个foac2-的桥联氧原子配位形成扭曲的四方锥配位环境。在375 nm激发波长激发下,1的发射峰位于390 nm。  相似文献   
37.
本文通过恒温水浴法和溶剂热法分别合成了两种配合物Fe(3PCA)2(H2O)2(1)和[Cu(3PCA)(Im)]n(2)(3PCA=pyrazole-3-carboxylic acid,Im=imidazole),并用X-射线单晶衍射仪测定了它们的晶体结构。结果表明:配合物(1)属于单斜晶系,空间群为P21/c,晶胞参数为:a=5.11446(19),b=11.4930(4),c=9.4084(3),β=95.692(4)°,V=550.30(3)3,Z=2;配合物(2)属于单斜晶系,空间群为P21/c,晶胞参数为:a=11.7198(4),b=8.5094(3),c=8.9703(3),β=111.765(4)°,V=830.82(5)3,Z=4。对配合物(2)进行了磁性质研究,结果表明,铜离子之间存在反铁磁相互作用。  相似文献   
38.
The title Zn(II) coordination polymer {[Zn_2(BTC)(HBTC)(dpa)(Hdpa)]·3H_2O}_n(1,H_3BTC = 1,3,5-benzenetricarboxylic acid,dpa = 4,4?-dipyridylamine),has been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction,powder X-ray diffraction,IR spectroscopy and Fluorescence spectroscopy.Complex 1 belongs to the triclinic system,space group P1,a = 9.9415(4),b = 13.5859(8),c = 15.2987(5) ?,α = 96.301(4),β = 107.944(3),γ = 103.575(4)°,V = 1873.48(14) ?~3,Z = 2,μ = 1.365 mm~(-1),Dc = 1.672 g/cm~3,Mr = 943.44,F(000) = 964,the final R = 0.0314 and wR = 0.0710 with I 2σ(I).Complex 1 displays a two-dimensional bilayer coordination polymer.Complex 1 shows fluorescence in the solid state at room temperature.  相似文献   
39.
Cu(Ⅱ)-牛磺酸缩水杨醛席夫碱配合物的合成及晶体结构   总被引:21,自引:1,他引:21  
The title complex was synthesized by reaction of taurine salicylic schiff base(TSSB), O-phenanthroline(phen) and cupric acetate in water-ethanol solution. The crystal structure was determined by X-ray diffraction method and the chemical formula weight of the complex is 498.00. And the crystal structure belongs to orthorhombic system with space group Pbcn and cell parameters: a=31.072(4)?, b=12.8909(18)?, c=10.3478(14)?; V=4144.7(10)?3,Z=8,Dc=1.596Mg·m-3,μ=1.197mm-1 and F(000)=2048. The compound is an one-dimensional chain complex of infinite length connecting with hydrogen bonds. The Cu(Ⅱ) was coordinated by two oxygen atoms and three nitrogen while the O atoms of Ac- groups did not coordinate. At the same time the Cu(Ⅱ)formed a distorted tragonal cone. Besides the capacities of coordination to Cu(Ⅱ) of atoms were discussed.  相似文献   
40.
为表征中国花鲈耳石的微结构,应用数码照相机、热重分析仪与X-射线衍射仪对中国花鲈耳石的外观形貌、化学组成与晶体结构进行记录及表征。结果显示:中国花鲈耳石为较厚的宽叶形,表面有不同大小的晶状突,边缘有叶形晶状突,内弯面有中央突,弯曲背面有嵴突及几乎贯穿整个耳石的主凹槽;TGA曲线分为晶体间隙水的挥发,有机质和无机盐的灰化与分解,碳酸钙热分解为氧化钙等三个平台,化学组成中碳酸钙含量为97.92%,水、有机质和其它无机盐含量为2.08%;XRD晶体结构属于稳定性较差的含很少量第二相的霰石。组成与结构的表征有助于鱼类耳石的化学生物学分类数据库的建立,也丰富了耳石的研究内涵。  相似文献   
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