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271.
Characterization of Undoped and Cu-Doped ZnO Thin Films Deposited on Glass Substrates by Spray Pyrolysis
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Metin Bedir Mustafa Oztas A. Necmeddin Yazici E. Vural Kafadar 《中国物理快报》2006,23(4):939-942
Undoped and copper doped zinc oxide (ZnO) thin films have been prepared on glass substrates by spray pyrolysis technique. The films were doped with copper using the direct method by addition of a copper salt (CuCl2) in the spray solution of ZnO. Variation of structural, electrical, optical and thermoluminescence (TL) properties with doping concentrations is investigated in detail. 相似文献
272.
273.
This is the first one of two companion papers focusing on the establishment of a new path for the expectation value dynamics of the quantum mechanical operators. The main goal of these studies is to do quantum mechanics without explicitly solving Schrödinger wave equation, in other words, without using wave functions except their initially given forms. This goal is achieved by using Ehrenfest theorem and utilizing probabilistic evolution approach (PEA). PEA, first introduced by Metin Demiralp, is a method providing solutions to the nonlinear ordinary differential equations by transforming them to a set of linear ODEs at the cost of denumerably infinite dimensionality. It is recently shown that this method produces analytic solutions, if the initial conditions are given appropriately at some special cases. However, generalization of these conditions to the quantum mechanical applications is not straightforward due to the dispersion of the quantum mechanical systems. For this purpose, multivariate moment problems for the integral representation of the Kronecker power series are introduced and then solved yielding to more specific and precise convergence analysis for the quantum mechanical applications. 相似文献
274.
A new aminoquercitol derivative was synthesized starting from 1,4-cyclohexadiene. Photooxygenation of cyclohexa-1,4-diene afforded anti-2,3-dioxabicyclo[2.2.2]oct-7-en-5-yl hydroperoxide as the main product. The formed hydroperoxy endoperoxide was reduced with LiAlH4 to produce anti-2,3-dioxabicyclo[2.2.2]oct-7-en-5-ol. Protection of alcohol with acetyl chloride followed by reduction of the endoperoxide with thiourea, and then palladium-catalyzed ionization/cyclization reaction gave an oxazolidinone derivative. Hydrolysis of the oxazolidinone ring and acetylation gave an amino compound. Oxidation of the double bond in the amino compound with OsO4 followed by acetylation gave the amino tetraacetate and removal of the acetate groups furnished the desired aminoquercitol whose exact configuration was determined by X-ray diffraction analysis. 相似文献
275.
Huseyin Alim Azmi Ali Altintas Metin Arik Ali Serdar Arikan 《International Journal of Theoretical Physics》2010,49(3):633-643
We consider two parameter deformed boson algebra and investigate the inhomogeneous invariance quantum group of this system.
We find the R-matrix which collects all information about the non-commuting structure of the quantum group. We extend our study to the
d-dimensional case. 相似文献
276.
Şimşek Nermin Arici Cengiz McKee Michael L. Ülkü Dinçcer Balci Metin 《Structural chemistry》2001,12(3-4):305-311
The electrophilic addition of bromine to dimethyl 7-oxabicyclo[2.2.1]hepta-2,5-diene-2,3-dicarboxylate 10 at 0 and –60°C led in high yield to the formation of dibromide 11. However, high-temperature bromination of 10 in carbon tetrachloride at 77°C gave four products 12–15, three of them with nonrearranged skeleton. Similarly, bromination of the dibromides 14 and 15 at 77°C yielded the nonrearranged tetrabromides 13 and 16, respectively. The structure of the tetrabromide 13 was solved by single-crystal X-ray analysis. The formation mechanism is discussed and supported by calculations. 相似文献
277.
278.
Metin Durgut 《Nuclear Physics B》1976,116(1):233-252
The bound-state baryon problem with N quarks in an SU(N) gauge model of strong interactions is investigated in one-space and one-time dimensions. A study of planar diagrams yields color singlet “baryon” states of quarks that have infrared divergence-free mass spectra. The resulting integral equation turns out to be identical to the one obtained in a particular string model. 相似文献
279.
Cigdem O. Metin Larry W. Lake Caetano R. Miranda Quoc P. Nguyen 《Journal of nanoparticle research》2011,13(2):839-850
In this study, we present quantification methods for nanoparticle stability analysis using non-intrusive analytical techniques:
attenuated total reflectance, Fourier transform infrared (ATR-FTIR) spectroscopy, ultraviolet–visible (UV–vis) spectrophotometer,
zeta potential analyses, and dynamic light scattering (DLS). We use these techniques to study the stability of silica nanoparticle
dispersions and the effects of pH, temperature, and electrolytes that would be encountered in oil field brines in a reservoir.
Spectral analysis of the Si–O bond at wavenumber of 1110 cm−1 with the ATR-FTIR indicates a structural change on the surface of silica particles as the dispersion pH changes, which agrees
with zeta potential measurements. We define a critical salt concentration (CSC) for different salts, NaCl, CaCl2, BaCl2, and MgCl2, above which the silica dispersion becomes unstable. Three distinct stages of aggregation occur in the presence of salt:
clear dispersed, turbid, and separated phases. Divalent cations Mg2+, Ca2+, and Ba2+ are more effective in destabilizing silica nanoparticle dispersion than the monovalent cation Na+. The CSC for Na+ is about 100 times more than for Ca2+, Ba2+, and Mg2+. Among the divalent cations studied, Mg2+ is the most effective in destabilizing the silica particles. The CSC is independent of silica concentration, and lowers at
high temperature. 相似文献
280.
Baran A Bekarlar M Aydin G Nebioglu M Şahin E Balci M 《The Journal of organic chemistry》2012,77(3):1244-1250
1,3,3a,7a-Tetrahydro-2-benzofuran was used as key compound for the synthesis of various bishomoinositol derivatives. The diene was subjected to an epoxidation reaction for further functionalization of the diene unit. The bisepoxide obtained was submitted to a ring-opening reaction with acid in the presence of water. Various bishomoinositols were synthesized. However, when the reaction was carried out in the presence of acetic anhydride, a substituted 3-oxabicyclo[3.3.1]nonane skeleton was formed. The mechanism of the formation of the products is discussed. 相似文献