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1.
The title compound (4,4'-H2bipy)[CdBr4]·H2O 1 has been synthesized via hydrothermal reaction and characterized by X-ray diffraction. The crystal belongs to monoelinic,space group P21/c with a=8.260(3), b=23.926(7), c=9.774(2) (A), β=106.777(9)°,C10H12Br4CdN2O, Mr=608.26, V=1849.4(9)(A)3, Z=4, Dc=2.185 g/cm3, S=1.005, μ(MoKα)=9.814 mm-1, F(000)=1128, R=0.0646 and wR=0.0989. The crystal structure analysis of 1reveals that the title compound features an isolated structure, based on discrete 4,4'-H2bipy moieties and lattice water molecules which are linked by hydrogen bonds together with tetrahedral cadmium atoms terminally coordinated by four bromine atoms.  相似文献   
2.
直接甲醇燃料电池PtRuMo/C电催化剂的制备和性质;直接甲醇燃料电池;电催化剂;甲醇电氧化  相似文献   
3.
The title compound (4,4'-H2bipy)[CdBr4]·H2O 1 has been synthesized via hydrothermal reaction and characterized by X-ray diffraction. The crystal belongs to monoelinic,space group P21/c with a=8.260(3), b=23.926(7), c=9.774(2) (A), β=106.777(9)°,C10H12Br4CdN2O, Mr=608.26, V=1849.4(9)(A)3, Z=4, Dc=2.185 g/cm3, S=1.005, μ(MoKα)=9.814 mm-1, F(000)=1128, R=0.0646 and wR=0.0989. The crystal structure analysis of 1reveals that the title compound features an isolated structure, based on discrete 4,4'-H2bipy moieties and lattice water molecules which are linked by hydrogen bonds together with tetrahedral cadmium atoms terminally coordinated by four bromine atoms.  相似文献   
4.
使用X光背景照明诊断技术得到时间分幅。两维空间分辨消融型球靶内爆物理过程的信息,与解析模型比较推算出部分内爆过程动力学参量。在此基础上进一步讨论并建议使用双分幅X光背景照明诊断技术的可行性。  相似文献   
5.
Four isostructural lanthanide compounds formulated as {[Ln4(μ3-OH)4(L-asp)3- (H2O)10](ClO4)5·10H2O}n (Ln=Nd (1), Sm (2), Eu (3), Gd (4); asp=aspartic acid) were synthe- sized by a conventional solution reaction. Their structures were characterized by single-crystal X-ray diffraction, IR spectroscopy and elemental analyses (EA). It reveals that they crystallize in the chiral P212121 space group. Their structures feature a homochiral three-dimensional (3D) lan- thanide-organic framework, which contains a cubic [Ln4(μ3-OH)4]8+ cluster sub-building unit (SBU). Additionally, the photoluminescence property of Eu compound was investigated in the solid-state at room temperature.  相似文献   
6.
徐新发  邵晓红 《物理学报》2009,58(3):1908-1916
采用基于第一性原理的密度泛函理论平面波超软赝势法, 研究了Y掺杂SrTiO3体系的空间结构和电子结构性质, 得到了优化后体系的结构参数, 掺杂形成能, 能带结构和电子态密度. 对比掺杂浓度为0125, 025, 033时,Sr1-xYxTiO3和SrTi1-xYxO3的掺杂形成能,发现Y替代Sr能形成更稳定的结构. 对Sr1-xYxTiO3x=0, 0125, 025, 033) 的结构进行了优化,结果表明Y替代Sr后, 随着掺杂浓度增大, 体系的晶格常数逐渐减小, 稳定性逐渐增强. 对不同掺杂浓度的Sr1-xYxTiO3能带结构的计算结果表明:纯净的SrTiO3是绝缘体, 价带顶在R点, 导带底在Γ点, 费米能级处于价带顶; 掺杂Y后, 费米能级进入到导带底中, 体系呈金属性;掺杂浓度越大,费米能级进入导带的位置越深,禁带宽度也近似变宽. 关键词: 3')" href="#">SrTiO3 电子结构 掺杂 VASP  相似文献   
7.
Four configurationally and conformationally related Zn(II) complexes with a tridentate ligand namely, N-(2-pyridylmethyl)-phenylalanine (Hpmpa), have been synthesized by hydrothermal reactions. [Zn(L-α-pmpa)2·HaO] 1: orthorhombic, space group P21212 with a = 15.1091(7), b = 16.2417(8), c = 5.9972(3) A, V= 1471.70(12)A^3, Z = 2, Mr = 593.97, Dc = 1.340 g/cm^3,μ = 0.879 mm^-1, F(000) = 620, Rint= 0.0205, R = 0.0450 and wR = 0.1578 for 3102 observed reflections with I 〉 2σ(I); [Zn(D-α-pmpa)2·2H2O] 2: orthorhombic, space group P21212 with a = 15.1023(6), b = 16.2516(7), c = 6.0024(2)A, V= 1473.21(10)A^3, Z = 2, Mr = 611.98, Dc = 1.380 g/cm^3,μ = 0.882 mm^-1, F(000) = 640, Rint= 0.0337, R = 0.0484 and wR = 0.1435 for 2408 observed reflections with I 〉 2σ(I); [Zn(L-β-pmpa)2] 3: monoclinic, space group C2/c with a = 27.8667(5), b = 5.60350(10), c = 19.9636(2)A β = 120:2210(10)°, V = 2693.66(7)A^3, Z = 4, Mr = 575.95, De= 1.420 g/cm^3,μ = 0.955 mm^-1, F(000) = 1200, Rint= 0.0345, R = 0.0358 and wR = 0.1135 for 2251 observed reflections with I 〉 2σ(I); and [Zn(D-β-pmpa)2] 4. They are all mononuclear discrete structures. The influence of temperature and pH on the conformation of structures has been investigated. Moreover, the photoluminescent properties of compounds 1 and 3 are also reported.  相似文献   
8.
采用溶胶-凝胶法制备了Fe3+掺杂的Fe-K2La2Ti3O10光催化剂, 并通过X射线衍射(XRD)、紫外-可见漫反射(DRS)、X射线光电子能谱(XPS)等技术对其进行了表征和分析, 考察了不同掺杂量对K2La2Ti3O10的性质及光催化分解水制氢活性的影响. 结果表明, Fe-K2La2Ti3O10在400-650 nm范围内显示强吸收, 光谱响应扩展到可见光区(λ>400 nm), 掺杂Fe3+后, K2La2Ti3O10的可见光区的光催化制氢活性显著提高, 掺杂量为nFe/nTi=0.04时活性最佳, 当催化剂用量为0.1 g, 反应液为CH3OH(30 mL)+H2O(90 mL)时, 产氢量达到1.92 μmol·h-1, 为未掺杂时的4倍.  相似文献   
9.
采用溶胶-凝胶法制备了Fe3+掺杂的Fe-K2La2Ti3O10.光催化剂,并通过X射线衍射(XRD)、紫外-可见漫反射(DRS)、X射线光电子能谱(XPS)等技术对其进行了表征和分析,考察了不同掺杂量对K2La2Ti3O10的性质及光催化分解水制氢活性的影响.结果表明,Fe-K2La2Ti3O10.在400-650 nm范围内显示强吸收,光谱响应扩展到可见光区(λ>400 nm),掺杂Fe3+后,K2La2Ti3O10.的可见光区的光催化制氢活性显著提高,掺杂量为nPe/nn=0.04时活性最佳,当催化剂用量为0.1 g,反应液为CH3OH(30 mL)+H2O(90 mL)时,产氢量达到1.92 μmol·h-1,为未掺杂时的4倍.  相似文献   
10.
通过高温固相反应合成了首例镧系-过渡金属-铋-四元硫属化合物:La2CuBiS5。该化合物属于正交晶系,空间群:Pnma。其结构含有沿b方向的一维[BiCuS56-]带,带与带之间被La3+离子隔开。一维[BiCuS56-]带由[CuS4]四面体双链与BiS6八面体单链通过公顶点连接而成。漫反射光谱研究表明该化合物为半导体,能隙1.30eV。理论研究表明其为直接半导体,光学能隙跃迁来源于S3p到La5d轨道的电子迁移。  相似文献   
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