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71.
C. D. Eisenbach A. Göldel M. Terskan-Reinold U. S. Schubert 《Colloid and polymer science》1998,276(9):780-785
Transmission electron microscopy (TEM) studies on bipyridine (bpy) containing block copolymer systems showed the formation
of nanoscopic polymer–ion complexes through complexation with copper(I) ions which segregated to highly ordered columnar domains
of mesoscopic dimensions. The domains, i.e. stacks of [(bpy)2Cu(I)] complex moieties could be visualized by complementary TEM techniques. First, electron energy loss spectra (EELS) showed
the absorption edges of copper and nitrogen, which are specific for the bipyridine copper complexes. The element spectroscopic
imaging (ESI) technique allowed the imaging of the net copper and net nitrogen distribution, and the coinciding pictures exhibited
a microphase separated system in the case of a 3-block copolymer with complexed end segments. High resolution elastic bright
field images showed interference lines with a line to line distance of about 8 A which could be related to the Cu–Cu distance
in staggered Cu(I)–bipyridine complexes.
Received: 6 August 1997 Accepted: 28 April 1998 相似文献
72.
为了研究白血病骨髓移植病人全血微量元素铜的变化及其意义 ,用原子吸收光谱法检测了正常对照组与白血病骨髓移植患者预处理前及移植后骨髓空虚期全血微量元素铜的含量。结果表明 ,正常对照组全血铜浓度与白血病骨髓移植患者预处理前全血铜浓度差异无显著性 (P >0 0 5 ) ,而与骨髓空虚期全血铜浓度有显著性差异 (P <0 0 5 ) ,说明白血病缓解后血铜接近正常对照组水平 ,而白血病骨髓移植患者预处理后骨髓空虚期全血铜含量高于正常对照组 ,说明预处理影响微量元素铜的代谢 ,本文就其影响机理进行了研究 相似文献
73.
Bagiyan G. A. Koroleva I. K. Soroka N. V. Ufimtsev A. V. 《Russian Chemical Bulletin》2003,52(5):1135-1141
Side self-oxidation of thiols was studied. It was found that these reactions in neutral and alkaline solutions are induced by impurities of variable-valence metals. The ability of transition metals to catalyze oxidation of thiols changes in the order Cu > Mn > Fe > Ni Co. The plot of the self-oxidation rate vs. pH passes through a maximum whose position on the pH scale depends on both the nature of metal and the structure of the thiol oxidized. For thiols having different structures, the kinetic orders in reactions catalyzed by copper ions differently vary with pH, which is apparently associated with the formation of complexes possessing different catalytic activity. 相似文献
74.
The title compound, {[Cu(2,2'-bipy)(C7H4O5S)(H2O)2](H2O}n (2,2'-bipy = 2,2'- bipyridine), was synthesized by the hydrothermal reaction of Cu(NO3)2(3H2O, 2,2'-bipyridine and 2-sulphobenzoic acid, and structurally characterized by single-crystal X-ray diffraction analysis. The crystal is of triclinic, space group P with a = 9.21(3), b = 10.17(3), c = 10.77(3) (A), α = 77.017(16), β = 89.80(8), γ = 68.46(7)°, V = 911(5) (A)3, Z = 2, (D/s)max = 0.001, Mr = 473.94, Dc = 1.728 g/cm3, μ(MoKα) = 1.365 mm-1, F(000) = 486, the final R = 0.0246 and wR = 0.0628 for 3809 observed reflections with I > 2σ(I). The mononuclear crystal structure extends into a two-dimensional net- work via hydrogen-bonding interactions and a three-dimensional framework is further formed by means of π-π stacking interactions. 相似文献
75.
D. V. Soldatov J. A. Ripmeester 《Journal of inclusion phenomena and macrocyclic chemistry》2001,39(1-2):81-84
Inclusion of tert-butylbenzeneinto the l-D channel of the titlehost matrix results in a-[CuL2]1/3(tert-butylbenzene)inclusion compound(trigonal, space groupR =3;a = 24.495(3),c = 10.510(2) Å,V = 5461(1) Å3,Z = 9;R = 0.049). The observed guest–host mole ratio of 1/3 was confirmed by X-ray diffraction and arises from the stoichiometric filling of the larger wide segments of the channel. This contrasts with the benzene inclusion compound studied previously, where both the larger and smaller wide segments were occupied to give a 2/3 guest–host stoichiometry. A comparison of these two structures explains the experimental fact that the guest–host mole ratios for inclusions of the title host lie between values of 1/3 and 2/3for 20 different benzene derivatives. 相似文献
76.
过渡金属-碱土金属铜镁异双核配合物的合成、晶体结构和性质研究 总被引:2,自引:0,他引:2
The transition metal and alkaline earth metal heterobinuclear complex[CuMg(TS)(H2O)·H2O],where TS is the schiff base N,N′-bis(3-carboxylsalidene)trimethylenediamine, was synthesised and its crystal structure was determined by the single-crystal X-ray diffraction method at room temperature. It crystallizes in the monoclinic system, space group P21/n. The lattice parameters are a=12.041(2)?, b=14.736(3)?, c=12.062(2)?, β=118.00(3)°, Z=4 with R1=0.0364. The thermal property and EPR studies of the complex according to crystal structure are also investigated. CCDC: 182408. 相似文献
77.
78.
以铜离子为模板的褐藻酸凝胶对铜离子的选择性富集研究 总被引:2,自引:0,他引:2
以铜离子为模板,制备了褐藻酸凝胶(Cu-alginate),通过吸附实验及过柱渗滤实验,试验了该吸附剂对铜离子的选择性吸附性能,并且采用该吸附剂富集了自来水中微量的Cu^2 ,结合原子吸收法测定了水样中Cu^2 的含量。结果表明:该吸附剂对Cu^2 有较高的选择性吸附性能,显著优于一些化学合成铜离子模板缩聚物及非铜模板褐藻酸凝胶(如Ca-alginate),非重金属离子(如K^ 、Na^ 、Ca^2 )及某些重金属离子(如Ni^2 、Cd^2 )等对Cu^2 的吸附均不产生明显干扰。用该吸附剂富集水中的微量铜离子,回收率可达97.7%。 相似文献
79.
为观察二硫化碳(CS2)对机体铜,锌水平的影响,对某化纤厂35名接触CS2工人和41名非接触工人的血铜,锌值进行调查,比较,并进行了动物染毒实验。SD大鼠吸入CS2浓度分别为5和50mg/m^3,每日5h,每周6d,连续6个月,于染毒2,4,6个月时测定血浆铜,锌值及染毒6个月时肝脏铜,锌含量。结果显示,CS2接触组工人血铜,锌水平较对照组显著降低(P<0.05)。在CS2染毒6个月时,50mg/m^3 CS2染毒组血浆及肝脏铜水平均较对照组及5mg/m^3 CS2染毒组显著降低(P<0.05)。可见接触CS2能干扰机体铜,锌代谢,导致体内铜,锌含量减少。 相似文献
80.
Deprotonated Dithiocarbamic Acid Esters as Thiolate S-Donor Ligands. Structures of Ph(H)NC(S)SMe, Co(PhNC(S)SMe)3, and Cu6(PhNC(S)SMe)6 The reaction of N-phenyl-S-methyldithiocarbamate, PhN(H)C(?S)SMe, ( 1 ) with cobalt(II) and copper(II) salts yields the monomeric compound CoIII(PhNC(S)SMe)3 ( 2 ) and the hexameric compound Cu6I(PhNC(S)SMe)6 ( 3 ). These complexes contain the negatively charged imino-thiolate ligand PhN?C(? S)SMe, which has been formed by deprotonation of 1 . The crystal structures of 1 – 3 have been determined. 1 forms centrosymmetrical dimers through N? H …? S bridge bonds, the conformation in the solid state and in solution is Z,E′. CoIII shows in 2 a trigonal-antiprismatic coordination, with the ligands acting as N,S-chelates. 3 contains an octahedral Cu6-core with Cu …? Cu-distances ranging from 276.3(5) to 305.7(4) pm. Each copper center is trigonally coordinated to one nitrogen and two sulfur atoms of three different ligands. Crystal data: 1 , triclinic, space group P1 , a = 590.5(6), b = 869.0(1), c = 968.5(9) pm, α = 67.29(8), β = 78.44(8), γ = 81.64(9)°, Z = 2, 1 775 reflections, R(Rw) = 0.0317(0.032). 2 , orthorhombic, space group Pbca, a = 978.0(2), b = 1 842.9(4), c = 3 059.7(6) pm, Z = 8, 1 129 reflections, R(Rw) = 0.0997(0.0886). 3 , monoclinic, space group P21/c, a = 1 363.1(3), b = 1 342.8(3), c = 1 671.9(3) pm, β = 103.48°, Z = 2, 1 374 reflections, R(Rw) = 0.0708(0.0617). 相似文献