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61.
一维链状铁(Ⅱ)配位聚合物的合成与晶体结构   总被引:1,自引:1,他引:0  
A coordination polymer, namely [Fe(DPPZ)(dipic)]n (1) (DPPZ=dipyrido[3,2-a∶2′,3′-c]phenazine and H2dipic=pyridine-2,6-dicarboxylic acid), has been obtained by using hydrothermal synthesis method. The crystal structure was determined by X-ray single crystal structure analysis with the following data: Monoclinic, P21/c, a=0.794 95(16) nm, b=3.601 1(7) nm, c=0.734 32(15) nm, β=106.07(3)°, V=2.020 0(7) nm3, Z=4, Mr=503.25, Dc=1.655 g·cm-3, F(000)=1 024, μ(Mo Kα)=0.795 mm-1, R=0.038 5 and wR=0.081 0. Complex 1 has octahedral coordination geometry and forms 1D zigzag coordination chains that organize into an unusual 3D supramolecular motif through noncovalent bonds, such as π-π stacking interactions and C-H…O hydrogen bonds. The result of TG analysis indicates that the title complex is stable till 290 ℃. CCDC: 716602.  相似文献   
62.
簿层树脂相吸光光度法测定痕量钴的研究   总被引:1,自引:0,他引:1  
提出了用薄层树脂相通过光度法测定痕量钴的新方法。本法具有灵敏度高,选择性好,快速等特点。钴离子(Ⅱ)与4-(5-氯-二吡啶)偶氮]-1,3-二氨基苯(简称5-Cl-PADAB)生成有色稳定配合物,将其富集在H+型(732~#)。阳离子交换树脂上,制作成薄层直接测定,λ_(max)=571nm。本法既克服了需特制1mm比色皿的困难,又提高了测定精密度,使推广树脂相光度法成为可能。用本法实测了天然水中痕量钴,检测限2.8μg·L~(-1),回收率≥98%。  相似文献   
63.
应用一种新的氧化铝制备方法-水合含碳氧化铝热解法, 通过引入模板导向剂和热稳定助剂, 制得了Al2O3纯度≥99.9%, 一次晶粒0.1 μm, 平均粒径0.2~3 μm, BET比表面积148.4 m2*g-1(900 ℃, 1 h焙烧)的活性氧化铝. 该方法所得产品性能稳定, 孔容大, 孔径分布合理, 纯度高. 样品经用户小批量试用认定 其新鲜态、老化后的比表面积和小杂质含量(P, S, Cl, Pb)指标均优于国内同类产品, Al2O3涂层粘结强度、涂层负载量等性能达到国际先进水平.  相似文献   
64.
1 INTRODUCTION The design and synthesis of metal-organic frame- work structure have been studied widely during the past decade not only because of their intriguing architectures but also their unexpected properties for potential practical applications in a wide number of fields, such as asymmetric catalysis, magnetism, pho- toluminescence and so on[1~3]. These novel struc- tures can be rapidly and efficiently synthesized from simple subunits, where the metal ions, bi- or multi- dentate o…  相似文献   
65.
李秀梅  董艳辉  王庆伟  崔运成  刘博 《结构化学》2007,26(12):1495-1498
A new metal-organic coordination complex [Zn(H2BPTC)(phen)2]n·3nH2O (BPTC = 3,3′,4,4′-benzophenone tetracarboxylate, phen = 1,10-phenanthroline) 1 has been obtained from hydrothermal reaction and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. In compound 1, the zinc cation is hexa-coordinated with two carboxylate oxygen atoms from one H2BPTC ligand and four nitrogen atoms from two different phen ligands, showing a slightly distorted octahedral geometry. Crystal data: C41H30N4O12Zn, Mr = 836.06, monoclinic, P21/c, a = 14.2714(9), b = 16.9386(10), c = 15.0151(9) , β = 101.3420(10)o, V = 3558.8(4) 3, Dc = 1.560 g/cm3, μ(MoKα) = 0.766 mm-1, F(000) = 1720, Z = 4, R = 0.0439 and wR = 0.1157 for 4123 observed reflections with I > 2σ(I).  相似文献   
66.
通过水热法合成了2个新的金属-有机超分子配合物[Ni(eoba)(phen)(H2O)2]·0.58H2O(1)和[Co(eoba)(phen)]2·H2O(2)(H2boba=4,4''-(乙烷-1,2-二氧基)-二苯甲酸,phen=菲咯啉),并对其进行了元素分析、红外光谱、热重和X射线单晶衍射测定。配合物12是同构的,每个配合物都是六配位的,菲咯啉分子上的2个氮原子、4,4''-(乙烷-1,2-二氧基)-二苯甲酸配体上的2个氧原子和2个配位水分子与金属配位。此外,还用高斯09程序PBE0/LANL2DZ方法对配合物1进行了自然键轨道(NBO)分析,计算结果表明配位原子与Ni原子之间存在着共价作用。  相似文献   
67.
杜成  任玉杰  王庆伟  金鹭 《有机化学》2013,(6):1279-1283
以白藜芦醇、氯乙酰氯、对甲苯磺酰氯、对甲苯甲酰氯为原料,合成9种新的白藜芦醇衍生物,其结构经IR,1HNMR,13C NMR和HRMS所表征.用3-(4,5-二甲基噻唑-2)-2,5-二苯基四氮唑溴盐(MTT)法测试了目标化合物抑制宫颈癌HeLa细胞的肿瘤活性,结果表明:化合物4a,6a,7b,8b和11c对HeLa细胞的抑制活性比白藜芦醇高,其中化合物6a和8b的抑制效果最明显,其IC50值分别为22.7和18.0μmol/L,活性高于白藜芦醇(IC50=114μmol/L),且在150μmol/L浓度下对HeLa细胞的抑制率达95.5%和87.7%.  相似文献   
68.
通过水热法合成了一个新的金属-有机配位聚合物[Mn(C2O4)(bimb)]n·0.25nH2O(H2C2O4=草酸,bimb=1,4-双(咪唑基-1-基)丁烷)。并对其进行了元素分析、红外光谱、紫外光谱、热重和X-射线单晶衍射测定。该配合物属于三斜晶系,P1空间群。在晶体结构中,锰原子为六配位与来自2个不同的C2O42-配体上的4个羧基氧原子和来自2个bimb配体上的2个氮原子配位,呈现畸变的八面体几何构型。  相似文献   
69.
We report a low-noise, high-signal-to-noise-ratio(SNR) balanced homodyne detector based on the standard transimpedance amplifier circuit and the inductance and capacitance combination for the measurement of the bright squeezed state in the range from 1 kHz to 100 kHz. A capacitance is mounted at the input end of the AC branch to prevent the DC photocurrent from entering the AC branch and avoid AC branch saturation. By adding a switch at the DC branch,the DC branch can be flexibly turned on and off on different occasions. When the switch is on, the DC output provides a monitor signal for laser beam alignment. When the switch is off, the electronic noise of the AC branch is greatly reduced at audio-frequency band due to immunity to the impedance of the DC branch, hence the SNR of the AC branch is significantly improved. As a result, the electronic noise of the AC branch is close to -125 dBm, and the maximum SNR of the AC branch is 48 dB with the incident power of 8 mW in the range from 1 kHz to 100 kHz. The developed photodetector paves a path for measuring the bright squeezed state at audio-frequency band.  相似文献   
70.
Two new complexes [Ag(bix)]n·n NAA·n H_2O(1) and [Cd(NAA)(phen)_2(H_2O)]2· 2CH_3COO-·H_2O(2)(bix = 1,4-bis(imidazol-1-ylmethyl)benzene,HNAA = α-naphthylacetic acid,phen = 1,10-phenanthroline) have been successfully synthesized under hydrothermal conditions.Their structures have been determined by elemental analyses,IR spectroscopy,TG and single-crystal X-ray diffraction analysis.The intermolecular hydrogen bonding or π-π stacking interactions extend the complexes into a 3D supramolecular structure.Moreover,the luminescent properties of complex 2 have been investigated in the solid state.  相似文献   
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