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111.
Issam M. Gabr Hala A. El-Asmy Mohamed S. Emmam Sahar I. Mostafa 《Transition Metal Chemistry》2009,34(4):409-418
Synthetic procedures are described that allow access to the new complexes cis-[Mo2O5(apc)2], cis-[WO2(apc)2], trans-[UO2(apc)2], [Ru(apc)2(H2O)2], [Ru(PPh3)2(apc)2], [Rh(apc)3], [Rh(PPh3)2(apc)2]ClO4, [M(apc)2], [M(PPh3)2(apc)]Cl, [M(bpy)(apc)]Cl (M(II) = Pd, Pt), [Pd(bpy)(apc)Cl], [Ag(apc)(H2O)2] and [Ir(bpy)(Hapc)2]Cl3, where Hapc, is 3-aminopyrazine-2-carboxylic acid. These complexes were characterized by physico-chemical and spectroscopic
techniques. Both Hapc and several of its complexes display significant anticancer activity against Ehrlich ascites tumour cells (EAC) in albino mice. 相似文献
112.
The nonlinear optical property of new polyester has been studied via second harmonic generation (SHG). The values of electro‐optic coefficients, d33 and d31, of the poled polymer film were 3.15 × 10 ?7 and 1.5 × 10?7 esu, respectively. Thermal behavior of this polyester was studied through thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). 4‐di‐(2′‐hydroxyethoxy)‐4‐diphenyl‐hydrazonomethyl was synthesized from the reaction of 3,4‐dihydroxy‐4‐diphenyl‐hydrazonomethyl with 2–chloro–1‐ethanol in a 1:2 mole ratio and subsequently reacted with terephthaloyl chloride (TPC) in the presence of pyridine, as catalyst, to produce the new nonlinear polyester. The chemical structures of the resulting monomers and polymer were characterized by CHN analysis, 1H‐NMR, FT‐IR, and UV–Vis spectroscopy. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
113.
Dissociation constants of some polyprotic acids and bases are determined from spectrophotometric and reversed-phase high performance liquid chromatographic data. A general equation relating additive properties of acids and bases to the pH of the solution is used for this purpose. The method is tested by applying it to the calculation of overlapping pKas without the prerequisite of measuring the limiting values of the property for the individual species that result from the dissociation of the solute. The possibility of applying the same method to hyperpolarizability measurements is pointed out, and a procedure, based on the general equation, for obtaining the activity coefficients of the ionic species as a function of the ionic strength is also suggested. 相似文献
114.
Beraldo Heloisa Kaisner Susan B. Turner Jennifer D. Billeh Issam S. Ives Janeice S. West Douglas X. 《Transition Metal Chemistry》1997,22(5):459-464
Copper(II) and nickel(II) complexes of phenylglyoxal and phenylpropane-1,2-dione bis{N(3)-methyl-, bis{N(3)-dimethyl-, bis{piperidylthiosemicarbazone} have been prepared and studied spectroscopically. The six bis(thiosemicarbazones) have been characterized by their melting points, as well as i.r., electronic and 1H-n.m.r. spectra. The four-coordinate copper(II) complexes have been studied by e.s.r. spectroscopy, and the copper(II) and nickel(II) complexes by spectroscopic techniques mentioned above. Upon formation of these complexes, the loss of protons from each thiosemicarbazone moiety occurs, and the bis(thiosemicarbazones) coordinate to the metal centres as dianionic, tetradentate N2S2 ligands. 相似文献
115.
In this paper, ART networks (Fuzzy ART and Fuzzy ARTMAP) with geometrical norms are presented. The category choice of these networks is based on the Lp norm. Geometrical properties of these architectures are presented. Comparisons between this category choice and the category choice of the ART networks are illustrated. And simulation results on the databases taken from the UCI repository are performed. It will be shown that using the Lp norm is geometrically more attractive. It will operate directly on the input patterns without the need for doing any preprocessing. It should be noted that the ART architecture requires two preprocessing steps: normalization and complement coding. Simulation results on different databases show the good generalization performance of the Fuzzy ARTMAP with Lp norm compared to the performance of a typical Fuzzy ARTMAP. 相似文献