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111.
A two-dimensional(2D) coordination polymer {[Cd2(sdb)2(dpb)2]·3H2O}n(1) was prepared by solvothermal reaction of two types of V-shaped ligands: 1,3-dipyridyl benzene(dpb) and deprotonated 4,4'-sulfonyldibenzoic acid(H2sdb). It was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. Complex 1 crystallizes in the monoclinic system, space group Fdd2 with a = 46.247(10), b = 9.994(2), c = 24.267(6) , V = 11216(4) 3, C60H46Cd2N4O15S2, Mr = 1387.97, Dc = 1.559 g/cm3, F(000) = 5296.0, μ = 0.902 mm-1 and Z = 8. Each [Cd(COO)]2 cluster links four sdb2- anions to form infinitely ABAB stacked 2D wave-like sheets, in which each sheet contains the same helical chains, and the helical directions of sheets A and B are reversed. Dpb links the rest coordinated sites of [(COO)Cd]2 cluster to form a 2D network. In addition, the solid fluorescence of 1 and dpb is also studied. 相似文献
112.
A two-dimensional(2D)coordination polymer{[Cd(bdc)(dpb)]·H2O}n(1)has been prepared by solvothermal reaction of 1,3-dipyridyl benzene(1,3-dpb)with deprotonated1,4-benzenedicarboxylate(H2bdc),and was characterized by elemental analysis,IR spectroscopy,and X-ray single-crystal diffraction.It crystallizes in the monoclinic system,space group C2/c with a=15.1839(12),b=20.7585(17),c=7.2989(6),β=117.3450(10)°,V=2043.5(3)3,C24H18N2O5Cd,Mr=526.81,Dc=1.712 g/cm3,F(000)=1056.0,μ=1.110 mm-1and Z=4.The neighboring Cd(II)ions link the bdc2-anions and 1,3-dpb to form an infinite 2D sheet,and such two2D sheets are interlocked with each other to form a 2D→2D sheet.Two groups of interlocked sheets are further linked together by intermolecularπ···πinteraction,giving a 3D supramolecular network.In addition,the fluorescence property of 1 was also studied. 相似文献
113.
本文以4,4′-二咪唑基二苯醚(BIDPE)和庚二酸(H2pim)为配体,溶剂热合成了一个互锁的二维配位聚合物{[Zn(BIDPE)(pim)]·(H2O)}n(1)。对其进行了红外、热重、粉晶衍射、单晶衍射等表征,配合物属于单斜晶系,空间群P21/c。相邻的Zn髤离子通过连接BIDPE和pim2-形成手性二维波浪形面,两个相邻的面相互互锁仍然形成2Dchiral的结构。相邻互锁的2Dchiral结构的螺旋方向相反,通过ABAB堆积最终形成了2Dachiral超分子框架。此外,本文也研究了配合物的荧光性能。 相似文献
114.
A TTF-type coaxial higher order modes (HOM) coupler has been used in a TESLA 9 cell cavity. It is impossible to measure the stop band characteristics of the HOM coupler with the cavity. A measurement device for the coaxial transmission line type for the HOM coupler has been designed at Peking University. Experimentally it was shown that the average voltage standing wave ratio of the coaxial transmission line is smaller than 1.08. The experimental results of the stop band characteristics of the TTF-type HOM coupler have been fitted for the simulation. This paper describes the design of the measurement device and discusses the experimental and simulation results of stop band characteristics of the HOM coupler. 相似文献
115.
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117.
A three-dimensional (3D) coordination polymer {[Co(bdc)(dpb)]·H2O}n (1) was prepared by solvothermal reaction of 1,3-dipyridyl benzene (dpb) with deprotonated 1,3-benzene- dicarboxylate (H2bdc), and was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group C2/c with α = 15.478(6), b = 12.865(5), c = 24.091(10) ?, β = 95.599(5)°, V = 4774(3) ?3, C24H18CoN2O5, Mr = 473.34, Dc = 1.267 g/cm3, F(000) = 1864.0, μ = 0.748 mm-1 and Z = 8. Each Co(II) ion links three bdc2- anions to form an infinitely 1D ladder-shaped chain containing binuclear [(COO)Co]2 cluster, and dpb links adjacent 1D chains to form a 3D pcu framework. In addition, the UV-vis of 1 was also studied. 相似文献
118.
提出了关于V字型铁电液晶(V-shaped Ferroelectric Liquid Crystal,VFLC)的等效电路模型,旨在将EDA技术引入对VFLC光电集成系统进行研究、开发和设计。该模型考虑了由铁电液晶盒多层结构和驱动电路引起的阻抗分配效应,以及极化与非极化锚定能对VFLC光电响应特性的影响。演示了电光迟滞曲线的反常迟滞、V字型及正常迟滞状态,并着重就自发极化强度对电光迟滞曲线的影响给出了模拟结果和分析。结果表明:强制电压随驱动信号频率的提高而增加,但增加速度随自发极化强度的提高而减慢;强制电压和迟滞反转频率随自发极化强度的变化均存在一个拐点,强制电压在自发极化强度为80nC/cm2时取到最小值(-0.084V),迟滞反转频率在自发极化强度为90nC/cm2时达到最大值(6.4Hz);自发极化强度小于80nC/cm2时,迟滞反转频率随自发极化强度准线性增加。模拟结果从量级和趋势上均与实验结果吻合。 相似文献
119.
A TTF-type coaxial higher order modes (HOM) coupler has been used in a TESLA 9 cell cavity. It is impossible to measure the stop band characteristics of the HOM coupler with the cavity. A measurement device for the coaxial transmission line type for the HOM coupler has been designed at Peking University. Experimentally it was shown that the average voltage standing wave ratio of the coaxial transmission line is smaller than 1.08. The experimental results of the stop band characteristics of the TTF-type HOM coupler have been fitted for the simulation. This paper describes the design of the measurement device and discusses the experimental and simulation results of stop band characteristics of the HOM coupler. 相似文献
120.
压电切口张开角和深度对其尖端力电损伤场的影响 总被引:2,自引:1,他引:1
基于三维各向异性压电损伤本构理论,导出了广义平面应力问题的损伤本构方程,并据此分析了压电薄板板边V形切口尖端附近的力电损伤,研究了切口张开角和深度对切口尖端力电损伤的影响规律.结果发现:和张开角对切口尖端损伤的影响相比,深度的影响更为明显;在张开角对切口尖端力损伤的影响规律方面,压电材料与一般弹塑性材料存在明显差异,原因在于压电切口尖端力电载荷比会随着深度的改变发生很大变化;不同深度下张开角与切口尖端力、电损伤关系曲线随着张开角的增大由发散逐渐会聚,不同张开角下深度与切口尖端力、电损伤关系曲线随着切口加深由会聚逐渐发散,并且电损伤曲线表现得更为明显. 相似文献