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61.
《Journal of Coordination Chemistry》2012,65(9):1560-1578
abstractPoly[tris(dimethylformamide)(μ3-2,4,6-triiodol-1,3,5-benzene tricarboxylic acid)-praseodymium (III)] {Pr(TIBTC)(DMF)3}n (1) (H3TIBTC = 2,4,6-triiodo-1,3,5-benzene tricarboxylic acid) was synthesized by the reaction of Pr(NO3)3·6H2O and H3TIBTC at 85°C in a pyrex vial. 1 was characterized by elemental analysis, IR, UV–vis, TGA, PXRD, and atomic force microscopy analytical means. Each of the central Pr ions and the three carboxyl groups from the same ligand constitute a SBU, which is then joined by a carboxyl group to form a building block. In order to further explore the functional properties of 1, we used this compound for adsorption experiments. It is found that 1 can effectively adsorb anionic dyes in aqueous solutions. In particular, there is a good adsorption efficiency for coomassie brilliant blue R-250. Therefore, 1 shows good prospects for selective adsorption of anionic dyes from wastewater solution. 相似文献
62.
《Journal of Coordination Chemistry》2012,65(11):1953-1962
Two new discrete Btz-bridged pentanuclear metal complexes, [HDMF][NaHg4(Btz)6I4] (1) and [Zn5(Btz)6(L)3(Ac)]?·?0.5MeOH?·?0.5H2O (2) (Btz?=?deprotonated benzotriazole, L?=?p-aminobenzoate, HDMF?=?protonated DMF, and Ac?=?acetate), were synthesized using three-layered diffusion and natural evaporation methods, respectively. In 1, the pentanuclear anion [NaHg4(Btz)6I4]? is composed of a tetrahedral arrangement of four four-coordinate Hg(II) ions centered on the six-coordinate Na(I), and thereby forming a rare Btz-bridged hetero-metal complex. Compound 2 is a neutral pentanuclear homo-metal complex, consisting of a tetrahedral arrangement of four five-coordinate Zn(II) ions centered on the fifth six-coordinate Zn(II). The thermal stabilities and solid-state photoluminescence of the two complexes have been investigated. 相似文献
63.
《Journal of Coordination Chemistry》2012,65(1-4):1-2
Abstract The FT-IR and Raman spectra of eight new complexes of formula ML2Ni(CN)4 (where M = Mn, Fe, Co, Ni, Cu or Cd and L = 2-chloropyridine; M = Ni or Cd and L = 2-bromopyridine) are reported. The spectroscopic results indicate that the complexes have structures consisting of corrugated polymeric layers of [M-Ni(CN)4]∞ with 2-substituted pyridine molecules bound directly to the metal (M). For a given ligand (2-Clpy or 2-Brpy) the effects of metal-ligand bond formation on the ligand modes are examined. Metal-ligand bond strengths of the halo-derivatives of pyridine (L = 2-Clpy or 2-Brpy), inferred by the effects on frequency shifts of certain ligand modes, have also been compared. 相似文献
64.
《Journal of Coordination Chemistry》2012,65(22):3659-3665
Some Schiff-base complexes of UO2(II) ion derived from 2-hydroxyacetophenone and aliphatic diamines under reflux conditions have been synthesized. The resulting ligands and their complexes have been characterized by elemental analyses (C, H, N), infrared, 1H NMR, 13C NMR and mass spectra. In these efficient reactions, Schiff-base complexes with important applications in analytical and organic chemistry are prepared. 相似文献
65.
Aishakhanam H. Pathan Ganesh N. Naik Raghavendra P. Bakale Shrinath S. Machakanur Kalagouda B. Gudasi 《应用有机金属化学》2012,26(3):148-155
A series of Co(II), Ni(II), Cu(II), and Zn(II) complexes of a tridentate hydrazone were prepared and characterized by various spectro‐analytical techniques and magnetic moment studies. The complexes were found to be monomeric and non‐electrolytes. The copper complex is electrochemically active in the applied potential range. The compounds synthesized in the present study have shown promising antiproliferative activity when screened using the in vitro method against two human cancer cell lines: HeLa and HepG2. The Escherichia coli DNA‐binding properties of all the compounds were investigated with UV–visible absorption spectrophotometric titrations, viscosity measurements, DNA melting experiments and gel electrophoreses measurements. The compounds were demonstrated to act as DNA intercalators with appreciable DNA‐binding constant values. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
66.
67.
The design of the mold and the choice of the injection parameters for metal injection molding (MIM) is required to maintain homogeneity of the filled mixture. However, powder segregation is unavoidable in MIM because of the significant difference in densities of the metallic powder and the polymer binder. To achieve an effective prediction of segregation effect, a biphasic model based on mixture theory is employed. The viscous behaviors of each phase and the interaction coefficient between the flows of the two phases should be determined. The solution of two coupled Navier–Stokes equations results in a tremendous computation effort. The previous development of an explicit algorithm makes the biphasic simulation much faster than that of the classic methods. However, it is strongly desired to reduce or even eliminate the numerous global solutions for pressure fields at each time step. Hence, a new vectorial algorithm is proposed and developed to perform the simulation only by vectorial operations. It provides the anticipated efficiency in the simulation of biphasic modeling, and the advantage to use the classic elements of equal‐order interpolations. Some results produced by the two algorithms are compared with the experimental values to validate the new vectorial algorithm. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
68.
J. P. Creen D. Vèron P. Belland 《International Journal of Infrared and Millimeter Waves》1986,7(11):1747-1767
The advantages of supported metal strip gratings with respect to free-standing metal meshes are pointed out for applications as laser output couplers. A new, simple formula for the power transmission through the strip grating on a dielectric plate is derived from a line equivalent-circuit model. This formula is in good agreement with measurements performed on several samples, at different submillimeter wavelengths. An application to output couplers of far-infrared gas discharge lasers allows to improve the reliability of such lasers.x Unité associée au CNRS. U.A. 836. 相似文献
69.
Critical comparisons are drawn between the basic electrical properties of semiconductor/metal, semiconductor/liquid, and semiconductor/conducting polymer junctions. A theoretical model is developed to describe the basic current-voltage properties of semiconductor contacts, with emphasis on the contrasts between ideal and observed behavior. Using the concepts from this model, the characteristics of a variety of semiconductor contacts are evaluated. The discussion focuses on the following semiconductors: Si, GaAs, InP, and II-VI compounds based on the Cd-(chalcogenide) materials. 相似文献
70.
巯基胺型螯合树脂经烷氧基环硫丙烷和二烷基胺基环硫丙烷改性后。合成了一系列新的螫合树脂.这些树脂与原树脂相比,对贵金属离子的吸附性能有一定的改善.特别是用二烷基胺基环硫丙烷改性后的树脂,效果更为明显.还讨论了树脂结构与吸附性能之间的关系. 相似文献