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991.
Karsten Schubert Theodor Alpermann Tobias Niksch Helmar Grls Wolfgang Weigand 《无机化学与普通化学杂志》2006,632(6):1033-1042
Synthesis and Analytical Characterization of Functionalized β‐Hydroxydithiocinnamic Acids and their Esters. Complex Chemistry towards Nickel(II), Palladium(II), and Platin(II) Starting from silyl‐protected 4‐hydroxy acetophenone ( 1 ) the 1,1‐ethenedihiolato complexes 3 – 5 were synthesised using carbon disulfide and potassium‐tert‐butylate as a base. After being deprotected, the resulting 4‐hydroxy‐substituted complexes 6 – 8 were esterified with DL‐α‐lipoic acid to obtain the compounds 9 – 11 . The resulting complexes were characterized using NMR spectroscopy, mass spectrometry and IR spectroscopy. 3‐substituted β‐hydroxydithiocinnamic acid methyl ester ( 12 ) was obtained via an analogous path of reaction using silyl‐protected 3‐hydroxy acetophenone ( 2 ), carbon disulfide and methyl iodide. After removing of the silyl group the resulting hydroxy group was esterified with DL‐α‐lipoic acid. Using the dithioacid ester 14 as a ligand the NiII ( 15 ), PdII ( 16 ) and PtII ( 17 ) [O,S] complexes were obtained. 相似文献
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993.
Using the mixture of cetyltrimethylammonium bromide (CTAB) and p‐Octyl polyethylene glycol phenyl ether (OP‐10) as templates, siliceous MCM‐48 materials can be synthesized with low molar ratio of CTAB to silica (0.139:1) and low concentration of mixed surfactants (ca.5%) and within a wide range of OP‐10/CTAB ratio (0.08?0.25). The materials were characterized by X‐ray powder diffraction, N2 adsorption/desorption isotherm, TEM, TG‐DSC and 29Si MAS NMR. Measurements indicated that the use of mixed surfactants allowed better condensation and higher ordering of the cubic mesostructure; at the same time, some properties of these materials were sensitive to the OP‐10/CTAB ratio. It was also found that the reduced pH of the gel which had been crystallized for a certain time gave a highly reproducible synthesis with a high silica yield (about 95%). Furthermore, the reaction mechanism of the synthesis is discussed in detail. 相似文献
994.
In this article, we apply a novel time‐dependent discrete variable representation (TDDVR) method proposed by Barkakaty and Adhikari to investigate tunneling through an Eckart barrier. This semi‐classical method is theoretically rigorous and straightforward to implement. Among the TDDVR formulations, this report presents the first derivation of a rigorous form of quantum force (QF) for the present perspective. The validity of this semi‐classical approach is demanded based on the excellent agreement of the tunneling probability with the corresponding quantum results. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004 相似文献
995.
Preparation and Crystal Structure of Rb2Ni3Se4 The compound Rb2Ni3Se4 was synthesized by heating a mixture of rubidium carbonate, nickel and selenium at 850°C in an atmosphere of hydrogen. The compound has a golden lustre and crystallizes with the K2Pd3S4-type structure; a = 10.555(3) Å, b = 27.588(6) Å, c = 6.031(6) Å, Z = 8, Fddd (No. 70). The structure can be described as a stacking of layers of the composition Rb2Ni3Se4 with a stacking sequence abcd. The electrostatic part of lattice energy (MAPLE) will be discussed for compounds of the compositions A2M3X4 (A K, Rb, Cs; M Ni, Pd, Pt and X S, Se). 相似文献
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997.
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1000.
A. A. Vedenyapin M. D. Baturova G. I. Ioseliani G. Kh. Areshidze 《Russian Chemical Bulletin》1997,46(1):76-80
The anodic oxidation of the carbon felt Carbonetcalon results in the formation of surface defects which serve as centers of
strong adsorption of PdII, NiII, and CuII ions. The electrochemical reduction of adsorbed ions makes it possible to obtain metallic catalysts, which undergo multiple
redox cycles without loss of metal. The catalysts are characterized by high dispersity of the reduced phase, high adsorption
capacity with respect to hydrogen, and 100% selectivity in hydrogenation of acetophenone.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 81–85, January 1997 相似文献