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51.
Sanchay Jyoti Bora Purabi Sarmah Prodeep Phukan Birinchi K. Das 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(9):m392-m394
The title compound, [Cu2(C7H5O2)4(C7H10N2)2], is a crystallographically centrosymmetric binuclear complex, with Cu atoms [Cu...Cu = 2.6982 (4) Å] bridged by four benzoate ligands. Each of the Cu atoms in this bunuclear copper(II) acetate hydrate analogue is present in an approximately square‐pyramidal environment, with four O atoms in a plane and the pyridine N atom at the apical site. Selected geometric parameters are compared with values for related tetrabenzoate complexes of copper(II). 相似文献
52.
The paper describes the synthesis and characterization of cobalt(II) bis (tartrato) cobaltate(II) trihydrate Co[Co[C4O6H4)2]·3H2O. The complex was characterized on the basis of elemental analysis, infrared, electronic, e.s.r. spectra and X-ray powder
diffraction studies. The thermal decomposition of the complex led to a mixture of Co2O3and Co3O4in air at about 400°C, whereas in nitrogen it was decomposed to a mixture of CoO and C at about 384°C. A tentative reaction
mechanism is suggested for the thermal decomposition of the complex in air and nitrogen.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
53.
Pankaj Hazarika Diganta Kalita Swapnalee Sarmah Ruli Borah Nashreen S. Islam 《Polyhedron》2006,25(18):3501-3508
Two new dinuclear oxo-bridged peroxo complexes of tungsten with coordinated dipeptides of the type, Na2[W2O3(O2)4(glycyl-glycine)2] · 3H2O (1) and Na2[W2O3(O2)4(glycyl-leucine)2] · 3H2O (2) have been synthesized from the reaction of H2WO4, 30% H2O2 and the respective dipeptide at pH ca. 2.5. Synthesis of the compounds, in addition to pH, is sensitive to reaction temperature and concentrations of the components. The compounds were characterized by elemental analysis, spectral and physico-chemical methods including thermal analysis. In the dimeric complexes the two W(VI) centres with edge bound peroxo groups are bridged by an oxo group. The dipeptides occurring as zwitterions bind the metal centers through O (carboxylate) atoms leading to hepta co-ordination around each W(VI). Thermal stability of the compounds as well as their stability in solution were determined. The compounds are highly stable toward decomposition in solutions of acidic as well as physiological pH. These compounds, besides another similar dimeric compound Na2[W2O3(O2)4(cystine)] · 4H2O (3) efficiently oxidized bromide to a bromination competent intermediate in phosphate buffer at physiological pH, a reaction in which only two of the peroxide groups of the complex species were found to be active. The complexes could also mediate bromination of organic substrate in aqueous-organic media. 相似文献
54.
Supply-chain coordination model with insufficient production capacity and option for outsourcing 总被引:1,自引:0,他引:1
In this paper, a mathematical model is developed to analyze the situation of lost sales from the supply-chain coordination perspective. In a two-stage supply chain, the supplier’s production capacity is less than the annual demand of the retailer. The supplier may recover the deficit by procuring the same from an external source at a certain price and then supplying it back to the retailer. Here, the conditions have been derived when the practice of external procurement may be a viable solution to enhance the profits of both the supplier and retailer in a coordinated approach. A numerical example is carried out to illustrate the efficacy of the developed model and the procedure developed for solving the problem. 相似文献
55.
Fred W. Decker Richard W. Couch John D. Pembrook Suryya K. Sarmah Bruce R. Meland 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1963,14(5):419-427
Zusammenfassung Es wird über die Untersuchung einer Zyklonenperiode in West-Oregon berichtet, die in koordinierter Weise konventionelle synoptische, luftelektrische und Radarbeobachtungen verwendet. Derartige kombinierte Analysen dürften geeignet sein, mesometeorologische Probleme, wie zum Beispiel die Kartierung der örtlichen Niederschlagsverteilung, zu lösen. 相似文献
56.
Gold nanocomposite of Polyaniline was prepared by chemical synthesis method and its thin film was made by drop casting. The Schottky junction of thin film was fabricated with aluminium metal. TGA analysis of the sample showed good stability. Current density-voltage characteristics of the junction showed good rectifying nature. The diode ideality factor is greater than unity. The junction showed good sensitivity to CO2 gas with decrease of forward current. The response time of the junction to CO2 showed good repeatability and recovery time is about 52 s. 相似文献
57.
Swadhin Chetia Samprity Sarmah Dr. Apurba Dutta Prof. Diganta Sarma 《European journal of organic chemistry》2023,26(26):e202300390
A copper acetate monohydrate catalyzed simple, effective and economic protocol has been developed for the construction of quinazoline derivatives via acceptorless dehydrogenative coupling of easily available 2-aminoaryl methanols and nitriles. The methodology was also highly effective for the synthesis of medicinally important quinolines analogues. The reactions proceeded in presence of KOtBu in toluene at 110 °C for 5 h without the requirement of inert condition, external additives and ligands. 相似文献