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51.
The silicate oxyapatites Ca2-3xLa8+2x□x(SiO4)6O2(x=0, 0.17, 0.33, 0.50, 0.67) was synthesized via a sol-gel method at low temperature. The apatite phases have been characterised by X-ray diffraction (XRD), conducting properties was studied by electrical chemistry impedance spectroscopy (EIS). The conductivity of La9.33□0.67(SiO4)6O2 is 1.58×10-3 S·cm-1 at 700 ℃, it is higher about 4 270 times than that of Ca2La8(SiO4)6O2, the activation energy is decreasing from 1.37 eV to 0.84 eV. With cation vacancies increasing,the conducting mechanism is gradually translation from a direct linear pathway free oxygen ion conduction to a curve pathway interstitial oxygen ion conduction. The electrical conductivities is almost independent of the oxygen partial pressure, this suggests that the oxyapatites exhibited almost pure O2- ion conduction over a wide range of oxygen partial pressure. 相似文献
52.
A 2D copper coordination polymer of [Cu2(3-PyOH)2(EDTA)]n (EDTA4-=ethylenediaminetetraacetate quadrivalent anion C10H12N2O8, 3-PyOH=3-hydroxypyridine) was synthesized and characterized by the element analysis, IR and single crystal X-ray diffraction. The title complex crystallizes in monoclinic system with space group P21/c, a=1.327 5(3) nm, b=0.930 39(19) nm, c=0.948 44(19) nm, β=108.21(3)°, and V=1.112 8(4) nm3, Z=2, R=0.025 2, wR=0.066 1. Each copper(Ⅱ) atom is five-coordinated by three O atoms and one N atom from two different EDTA4- groups and one N atom from 3-PyOH ligand, forming a distorted square-pyramidal coordination geometry. Two adjacent copper(Ⅱ) atoms are bridged by the bis-tetradentate EDTA4- groups, constructing a two-dimensional layer structure along bc plane. The adjacent Cu…Cu distances are 0.502 5(3) and 0.611 3(3) nm. CCDC: 618806. 相似文献
53.
A novel binuclear copper complex of [Cu(C14H8O3)(C9H7N)(C2H5OH)]2 was synthesized and characterized by elemental analysis, IR, thermal analysis and X-ray single crystal diffraction. The title complex crystallizes in monoclinic system, space group
P21/c with a=1.381 7(3) nm, b=1.184 3(2) nm, c=1.332 5(3) nm, β=104.77(3)°. Each copper(II) atom is five-coordinated by three oxygen atoms from two different 9-hydroxy-fluorene-9-carboxylate ligands, one quinoline nitrogen atom and one ethanol oxygen atom, forming a distorted square-pyramidal coordination geometry. Two copper(II) atoms are linked by two 9-hydroxy-fluorene-9-carboxylate ligands into a dimmer structure with the Cu…Cu separation being 0.298 39(8) nm. The dinuclear motifs are further linked into a two-dimensional supramolecular layer via hydrogen bonds interactions. CCDC: 272850. 相似文献
54.
用循环伏安法研究了(Mo3OCl6(O2CR)3)^-(其中R=CH3,H,CH2Cl)系列三核钼簇合物在CH3CN和DMF溶剂中的电化学行为,并用差热-热重手段研究了它们的热稳定性和热分解过程的可能机理。结果表明在不同溶剂中它们有相似的二对氧化还原峰,而且在同一溶剂中随着R基团吸电子能力的增强,相应的第一氧化还原电位值向正向移动,当R=CH3,H时,它们的起始分解温度分别为265℃和210℃,即 相似文献
55.
The novel coordination polymer {[Cd(p-CMSP)(Him)(H2O)]·3H2O}n (
p-CMSP2-=p-(carboxymethoxy)phenylthioacetate, Him=imidazole) was synthesized by the reaction of
Cd(NO3)2, imidazole and p-(carboxymethoxy)phenylthioacetic acid in an aqueous solution, and characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. The crystal structure is of monoclinic, space group
P21/c with a=1.144 0(2) nm, b=1.876 7(4) nm, c=0.877 89(18) nm, β=106.31(3)° and V=1.808 9(7)
nm3, Z=4, R=0.023 2, wR=0.051 4. Each Cd(II) atom displays a distorted octahedral coordination geometry, defined by three carboxyl O atoms from different
p-CMSP2- ligands, one S atom from thioether, one N atom from imidazole and one water molecule. Adjacent Cd(II) ions are bridged by
p-CMSP2- groups, resulting in a 2D layer structure. The adjacent Cd…Cd distances are 0.492 7 nm and 1.144 0 nm. Furthermore, such layers are linked through hydrogen bonds to form supramolecular network. CCDC: 269474. 相似文献
56.
由于吡啶氮羧酸及其衍生物具有多种键合模式和广泛的生物学特性,近10年来由其与金属离子所形成的配合物研究已引起了人们的极大关注[1].作为吡啶氮羧酸衍生物之一的2-氧-1(4H)-吡啶氮乙酸,是合成抗生素的重要医药中间体[2],而且同时具有羰基和羧基两个配位活性基团,具有灵活多样的配位方式、可塑性强和空间构型多变等结构特点,从而为构筑具有新颖拓扑网络结构和性能的超分子聚合物体系提供了丰富多彩的识别和组装方式. 相似文献
57.
一维螺旋链状配位聚合物[Cu(p-BDOA)(2,2′-bipy)·H2O]n的合成与表征(英) 总被引:5,自引:0,他引:5
A new copper(Ⅱ) coordination polymer, [Cu(p-BDOA)(2,2′-bipy)·H2O]n ( p-BDOA2-=benzene-1,4-dioxyacetate dianion; 2,2′-bipy=2,2′-bipyridine) has been synthesized and characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. The Crystal crystallizes in orthorhombic system, the space group is P212121, with the unit cell parameters a=0.698 4(1) nm, b=1.559 7(3) nm, c=1.750 6(4) nm and V=1.906 8(7) nm3, Mr=461.91, Z=4, R=0.057 5, wR=0.078 3. Each copper(Ⅱ) atom is six-coordinated and displays a distorted square pyramidal geometry with a one-capped base by one very long semicoordinate Cu-O(carboxylate) bond. Adjacent Cu(Ⅱ) ions are bridged by carboxylate groups, resulting in a one-dimensional helical chain. The adjacent Cu…Cu distance within the polymeric chain is 1.348 4 nm. Furthermore, such chains are linked through hydrogen bonds and π-π stacking interactions to form supramolecular network. CCDC: 219234. 相似文献
58.
一维链状的3-羧基苯氧乙酸铜配位聚合物[Cu(3-cpoa)(phen)(H2O)]n的合成与晶体结构 总被引:2,自引:0,他引:2
A novel coordination polymer [Cu(3-cpoa)(phen)(H2O)]n(3-cpoa2-=3-carboxylphenoxyacetate, phen=1,10-phenanthroline) was synthesized and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. Crystallographic facts are as follows: monoclinic crystal system, space group P21/n, a=0.688 96(14) nm, b=1.652 3(3) nm, c=1.651 1(3) nm, β=95.20(3)°, V=1.871 9(6) nm3, Z=4, Dc=1.618 g·cm-3, F(000)=932, μ=1.211 mm-1,R=0.048 2 and wR=0.062 2. The copper atom exhibits a distorted square pyramidal coordination geometry, involving two oxygen atoms of different 3-cpoa2- ligands, two nitrogen atoms of 1,10-phen ligand and one coordinated water molecule. The copper atoms are bridged by 3-cpoa2- ligand, forming a one-dimensional chain along c axis. The distance of adjacent Cu…Cu is 0.916 6(4) nm. A three-dimensional network structure is constructed by the intermolecular hydrogen bond and π-stacking interactions. CCDC: 219724. 相似文献
59.
一维链状4-硝基-3-羧甲基苯异丙酸镉配位聚合物{[Cd(3-CNPP)(Py)3]·2H2O}n的合成、晶体结构及热稳定性研究 总被引:1,自引:1,他引:1
A novel one-dimensional coordination polymer, {[Cd(3-CNPP)(Py)3]·2H2O}n (3-CNPP2-=2-(3-carboxymethyl-4-nitrophenyl)propionate dianion, Py=pyridine) was synthesized and characterized by the element analysis, IR, TG and single crystal X-ray diffraction. The title complex crystallizes in monoclinic system with space group P21/ n, a=0.974 81(19) nm, b=1.992 3(4) nm, c=1.459 8(3) nm, β=95.92(3)°, and V=2.820 0(10) nm3 Z=4, R=0.037 3, wR=0.083 8. Each cadmium(Ⅱ) atom is seven-coordinated by four oxygen atoms from two different 3-CNPP2- groups and three nitrogen atoms from three pyridine ligands, forming a distorted pentagonal bipyramindal coordination geometry. The cadmium(Ⅱ) atoms are bridged by the tetradentate 3-CNPP2- groups, constructing a one-dimensional zigzag chain structure along c axis. The adjacent distance of Cd…Cd atoms is 0.979 6 nm. The two-dimensional hydrogen-bonding supramolecular network was formed via the hydrogen bond interactions. CCDC: 254257. 相似文献
60.