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81.
Xiao-Zeng?LiEmail author Bao-Lin?Liu Dai-Zheng?Liao Zong-Hui?Jiang Shi-Ping?Yan 《Structural chemistry》2004,15(6):547-551
The title complex, [Cu(NiL)2(H2O)2](ClO4)2, has been obtained by self-assembly, where [NiL] is a new macrocyclic oxamido complex ligand. In the crystal, a new kind of supramolecular interaction between the carbon atoms of the oxamido group of each [NiL] complex ligand in a [Cu(NiL)2(H2O)2]2 + cation and the oxygen atom of one of the ester carbonyls of another [Cu(NiL)2(H2O)2]2 + cation, and C—HO, O—HO and interactions are observed and link the trinuclear fragments and perchlorate ions to form a 3D supramolecular network. 相似文献
82.
Quartz-crystal microbalance immunosensor for Schistsoma-japonicum-infected rabbit serum. 总被引:2,自引:0,他引:2
A quartz-crystal microbalance immunosensor (QCM) has been developed for the direct determination of Schistosoma-japonicum-infected rabbit serum. A self-assembled monolayer with carboxyl groups was first coated on a gold electrode of a quartz-crystal resonator by the spontaneous adsorption of 3-mercaptopropionic acid. Schistosoma-japonicum molecular antigen of 32 kD molecular weight was then covalently attached to the crystal surface. The QCM immunosensor was used to detect infected rabbit serum (IRS49-2000); a maximum titer of 1:800 was achieved. 相似文献
83.
LI Yan-Tuan JIANG Zong-Hui LIAO Dai-Zeng YAN Shi-Ping MA Shu-Lin WANG Gen-LinDepartment of Chemistry Nankai University Tianjin China 《中国化学》1994,(5)
Six novel u-oxamido binuclear complexes, namely Cu(oxpn)Ln(L)2(ClO4)3 (Ln: Eu, Gd, Tb, Nd, Ho, Er), where oxpn is N,N'-bis(3-aminopropyl) oxamido, L denotes 5-nitro-1,10-phenanthroline (abbreviated as NO2-phen), have been synthesized and characterized. The magnetic susceptibility of complexes Cu(oxpn)Gd(NO2-phen)2(ClO4)3.2H2O was measured over the 4-300 K and the observed data were successfully simulated by equation based on spin Hamil-tonian operator (H = -2JS1.S2), giving the exchange integral J(Cu-Gd)=-1.62 cm-1. This indicates a weak antiferromagnetic interaction between the Cu(Ⅱ) and Gd(Ⅲ) ions. 相似文献
84.
SynthesisandCrystalStructureofSquarateComplex[CuLaSm(C_4O_4)_4(H_2O)_(16)]·2H_2O¥ShiJing-Min;YanShi-Ping;LiaoDai-Zheng;JiangZong... 相似文献
85.
合成了3种以4,4'-联吡啶为桥联配体的三核环状Cu(Ⅱ)配合物[Cu_3(4,4'-bpy)_3·(phen)_3](ClO_4)_6·2H_2O(1)、[Cu_3(4,4'-bpy)_3](bpy)_3](ClO_4)_6·H_2O(2)和[Cu_3(4,4'-bpy)_3·(NO_2-phen)_3](ClO_4)_6·6H_2O(3)。经元素分析、电导、IR、电子光谱、ESR、磁化率等方法进行了表征,推定该配合物具有以4,4'-联吡啶为扩展桥的结构。利用Heisenberg模型求得交换参数J值为-0.23cm-1(1)和-0.90cm-1(3),表明配合物中金属离子间仅有很弱的反铁磁交换作用. 相似文献
86.
用内消旋5,7,7,12,14,14-六甲基-1,4,8,11-四氮杂环十四烷(cth)和K_3[Fe(CN)_6〕合成了氢键连接的超分子化合物[H_3cth][Fe(CN)_3]·3H_2O.该化合物的晶体属三斜晶系,P-1空间群,晶胞参数a=0.930 97(9)nm,b=1.051 60(11)nm,c=1.638 47(17)nm,a=101.077(2)°,β=90.860(2)°,γ=111.671(2)°, V=1.456 4(3) nm3, Z=2, R=0.0415.晶体中质子化的大环四胺与六氰合铁(Ⅱ )离子之间通过氢键连接成二维层状结构,而水分子所形成的氢键使化合物呈现三维超分子网络. 相似文献
87.
Shu-Lin Ma Shi Ren Yue Ma Shi-Ping Yan Dai-Zheng Liao 《Journal of chemical crystallography》2010,40(11):1011-1015
Abstract
A mononuclear fragment [Cu(L)Cl]ClO4 (1) and a cyano-bridged CuII–NiII binuclear complex [CuL][Ni(CN)4]·0.25H2O (2) (L = 1,3,6,8,11,14-hexaazatricyclo[12.2.1.18,11]-octadecane), have been prepared and characterized. X-ray single crystal analyses indicate that the both complexes crystallize in the monoclinic crystalline system. The complex of 1 in P1n1 space group with unit cell constants a = 6.1176(6) ?, b = 11.9147(10) ?, c = 12.2041(12) ?, β = 98.816(5)° and 2 in the P21/n space group with unit cell constants a = 8.1419(13) ?, b = 14.695(2) ?, c = 16.863(3) ?, β = 98.375(2)° have been revealed. The complex 2 assumes a binuclear structure in which the nickel(II) ion is in a square planar environment and the copper(II) is in a square-prism geometry environment. 相似文献88.
Chen GJ Qiao X Tian JL Xu JY Gu W Liu X Yan SP 《Dalton transactions (Cambridge, England : 2003)》2010,39(44):10637-10643
Two Eu(III) complexes, [Eu(acac)(3)(dpq)] (1) and [Eu(acac)(3)(dppz)] CH(3)OH (2) {viz. acetylacetonate (acac), dipyrido[3,2-d:20,30-f]quinoxaline (dpq), dipyrido[3,2-a:20,30-c] phenazine (dppz)}, have been synthesized and their DNA binding, photo-induced DNA cleavage activity and cell cytotoxicity are studied. The complexes display significant binding propensity to the calf thymus DNA in the order: 2(dppz) >1(dpq). Cleavage experiments using pBR322 supercoiled DNA suggest major groove binding for 2 and minor groove binding for 1. The mechanistic aspects on natural light (natural light in room during the day) and UV-A (365 nm) irradiation are via a mechanistic pathway involving formation of singlet oxygen and hydroxyl radical as the reactive species. The photo-induced DNA cleavage activity of 2 is also stronger than 1. The cytotoxicity of 1 and 2 against HeLa (cervical) cancer cells show that the IC(50) value of 19.11 ± 3.56 μM and 17.95 ± 5.47 μM, respectively. 相似文献
89.
著名物理学家海森伯曾于1929年访华,旋即被聘为中央研究院物理所名誉研究员,成为中国近代物理学史上第一个获此荣誉的外籍学者.文章对他来华的具体时间作出推断,述及其与早期中国物理学界某些人士的因缘. 相似文献
90.
A novel ligand, diethylenetriamine-N,N'-bis(acetyl-isoniazid)-N,N',N'-triacetic acid (H(3)L) has been synthesized from diethylene triamine pentaacetic acid (DTPA) and isoniazid. Ligand and its five neutral rare earth (RE=La, Sm, Eu, Gd, Tb) complexes holding promise of magnetic resonance imaging (MRI) were characterized on the basis of elemental analysis, molar conductivity, (1)H-NMR spectrum, FAB-MS, TG-DTA analysis and IR spectrum. The relaxivity (R(1)) of complexes and Gd(DTPA)(2-) used as a control were determined. The relaxivity of LaL, SmL, EuL, GdL, TbL and Gd(DTPA)(2-) were 0.14, 1.66, 3.14, 6.08, 2.79 and 4.34 l.mmol(-1).s(-1), respectively. The spin-lattice relaxivity of GdL was larger than that of Gd(DTPA)(2-). The relaxivity of GdL had also been investigated in human serum albumin (HSA) solution, the relaxivity of GdL was enhanced from 6.08 l.mmol(-1).s(-1) in water solution to 9.09 l.mmol(-1).s(-1) in HSA solution. In addition, thermodynamics stability constant of GdL complex was determined, the thermodynamic stability constant of GdL complex (K(GdL)=10(20.84)) was a few larger than that of Gd(DTPA)(2-) (K(Gd-DTPA)=10(20.73)). The results showed that complex of GdL may be a prospective MRI contrast agent with low osmotic pressure due to non-ion complex, high spin-lattice relaxivity, good stability and binding affinity for the serum protein. 相似文献