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Two cadmium(Ⅱ) compounds linked by a flexible dipyridyl ligand {[Cd2(Hbpma) Cl5(H2O)]·2H2O}n 1 and [Cd(Hbpma)Cl(H2O)2]2·2SO4·3H2O 2 (bpma = N,N-bis(3-pyridylmethyl)amine) have been synthesized and structurally characterized by single-crystal X-ray diffraction. Complex 1 crystallizes in triclinic, space group P with a = 9.5612(6), b = 11.3401(7), c = 11.5069(12), α = 112.8540(10), β = 106.5330(10), γ = 101.6680(10)°, V = 1030.77(14)3, C12H20Cd2Cl5N3O3, Mr = 656.36, Z = 2, Dc = 2.115 g/cm3, μ(MoKα) = 2.727 mm-1, F(000) = 636, S = 1.059, the final R = 0.0319 and wR = 0.0822 for 3443 observed reflections (I > 2σ(I)). For complex 2, it belongs to triclinic, space group P with a = 10.9487(4), b = 11.4197(4), c = 15.4288(5), α = 94.7470(10), β = 104.1000(10), γ = 104.42°, V = 1790.76(11)3, C24H42Cd2Cl2N6O15S2, Mr = 1014.46, Z = 2, Dc = 1.881 g/cm3, μ(MoKα) = 1.529 mm-1, F(000) = 1020, S = 1.050, the final R = 0.0178 and wR = 0.0451 for 6026 observed reflections (I > 2σ(I)). Complex 1 is found to have tetranuclear Cd(Ⅱ) clusters which are bridged by the protonated bpma ligands leading to one-dimensional coordination polymers, whereas complex 2 consists of binuclear Cd(Ⅱ) structures linked by the protonated bpma ligands. Both complexes are assembled into three-dimensional supramolecular structures through hydrogen bonding interactions.  相似文献   
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针对斜井中顶替流体密度差及套管偏心引起的顶替界面突进两相流体掺混严重的问题,考虑斜井密度差引起的驱动力沿周向角和半径的变化,建立了斜井偏心环空稳定顶替界面形状模型,利用该模型分析了密度差对顶替界面形状的影响,得到了不同井斜角及套管偏心条件下顶替流体的最优密度差及变化规律:斜井中顶替界面突进的位置及程度取决于套管偏心与密度差的相对作用,存在合理的密度差使得顶替界面长度最短;最优顶替流体密度差随套管偏心度的增加而增大,随井斜角的增大而减小;固井顶替时在满足压稳防漏的条件下直井所选用的密度差越大越好,水平井所选用的密度差应相对最小。  相似文献   
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醌式杂环(噻吩、吡咯、呋喃等)分子具有结构刚性、最高占据分子轨道(HOMO)/最低未占据分子轨道(LUMO)能级低、能级带隙窄和摩尔消光系数高等特点.醌式分子因其结构平面性特点,分子间作用力较强,因而分子间电荷传输能力强.目前,醌式杂环分子已成为有机半导体材料领域特别是有机场效应晶体管领域的研究热点.根据醌式杂环分子的结构特点,以端基为分类依据,综述了近年来醌式杂环化合物在分子设计、合成及应用性能等方面的研究进展,并展望了醌式杂环分子的发展前景.  相似文献   
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A new Cd(Ⅱ) complex with four nitronyl nitroxide radicals [Cd(NIT4Py)4Cl2](NIT4Py = 2-(4'-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) has been synthesized and structurally characterized by X-ray diffraction analysis.It crystallizes in triclinic,space group P1 with a = 7.2441(4),b = 13.6964(8),c = 13.7354(8) ,α = 89.8610(10),β = 77.9180(10),γ = 87.2250(10)°,V = 1331.01(13) 3,C48H64CdCl2N12O8,Mr = 1120.41,Z = 1,Dc = 1.398 g/cm3,μ(MoKα) = 0.573 mm-1,F(000) = 582,S = 1.043,the final R = 0.0257 and wR = 0.0641 for 4333 observed reflections(I > 2σ(I)).The title complex exists in the mononuclear-metal structures,in which each Cd(Ⅱ) ion adopts a distorted octahedral geometry and is coordinated by two Cl-anions and four pyridyl-N atoms from four NIT4Py ligands.The magnetic measurements show weak antiferromagnetic interactions between the nitroxide radicals.  相似文献   
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