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181.
Phase diagrams in mixed spin-3/2 and spin-2 Ising system with two alternative layers within the effective-field theory 下载免费PDF全文
The phase diagrams in the mixed spin-3/2 and spin-2 Ising system with two alternative layers on a honeycomb lattice are investigated and discussed by the use of the effective-field theory with correlations. The interaction of the nearest-neighbour spins of each layer is taken to be positive (ferromagnetic interaction) and the interaction of the adjacent spins of the nearest-neighbour layers is considered to be either positive or negative (ferromagnetic or anti-ferromagnetic interaction). The temperature dependence of the layer magnetizations of the system is examined to characterize the nature (continuous or discontinuous) of the phase transitions and obtain the phase transition temperatures. The system exhibits both second-and first-order phase transitions besides triple point (T P ), critical end point (E), multicritical point (A), isolated critical point (C) and reentrant behaviour depending on the interaction parameters. We have also studied the temperature dependence of the total magnetization to find the compensation points, as well as to determine the type of behaviour, and N-type behaviour in N′eel classification nomenclature existing in the system. The phase diagrams are constructed in eight different planes and it is found that the system also presents the compensation phenomena depending on the sign of the bilinear exchange interactions. 相似文献
182.
183.
Mustafa Özdemir Melek Erdoğdu Hakan Şimşek 《Advances in Applied Clifford Algebras》2014,24(1):179-192
In this paper, we examine eigenvalue problem of a rotation matrix in Minkowski 3 space by using split quaternions. We express the eigenvalues and the eigenvectors of a rotation matrix in term of the coefficients of the corresponding unit timelike split quaternion. We give the characterizations of eigenvalues (complex or real) of a rotation matrix in Minkowski 3 space according to only first component of the corresponding quaternion. Moreover, we find that the casual characters of rotation axis depend only on first component of the corresponding quaternion. Finally, we give the way to generate an orthogonal basis for ${\mathbb{E}^{3}_{1}}$ by using eigenvectors of a rotation matrix. 相似文献
184.
In this paper we consider a thermoelastic system of type III with boundary distributed delay. Under suitable assumption on the weight of the delay, we prove, using the energy method, that the damping effect through heat conduction given by Green and Naghdi's theory is still strong enough to uniformly stabilize the system even in the presence of time delay. 相似文献
185.
Mustafa Gülsu Mehmet Sezer 《Numerical Methods for Partial Differential Equations》2011,27(6):1628-1638
A numerical method based on the Taylor polynomials is introduced in this article for the approximate solution of the pantograph equations with constant and variable coefficients. Some numerical examples, which consist of the initial conditions, are given to show the properties of the method. © 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 27:1628–1638, 2011 相似文献
186.
Murat Cakici Mustafa Catir Semistan Karabuga Hamdullah Kilic Sabri Ulukanli Medine Gulluce Furkan Orhan 《Tetrahedron: Asymmetry》2010,21(16):2027-2031
A simple synthetic method for the preparation of enantiomerically pure (S)-4-aminoquinazoline alcohols from (S)-quinazolinone alcohols by key steps including chlorination, nucleophilic ipso substitution, and deacetylation is presented. Mutagenic and antimutagenic properties of the (S)-4-aminoquinazoline alcohols were investigated by using Salmonella typhimurium TA1535, and Escherichia coli WP2uvrA tester strains at 0.01, 0.1, and 1 μg/plate concentrations. (S)-4-aminoquinazoline alcohols were found to be genotoxically safe at the tested concentrations. Among the tested (S)-4-aminoquinazoline alcohols, the best antimutagenic activity was obtained with a methyl derivative at 0.1 μg/plate dose. 相似文献
187.
Gökhan Alpaslan Mustafa Macit Ahmet Erdönmez Orhan Büyükgüngör 《Structural chemistry》2011,22(3):681-690
The Schiff base compound (Z)-1-((4-phenylamino)phenylamino)methylene)naphthalen-2(1H)-one has been synthesized and characterized by IR, UV–Vis, and X-ray single-crystal determination. Molecular geometry from
X-ray experiment of the title compound in the ground state have been compared using the Hartree–Fock (HF) and density functional
method (B3LYP) with 6−31G(d,p) basis set. Calculated results show that density functional theory DFT and HF can well reproduce
the structure of the title compound. Using the time-dependent density functional theory (TD-DFT) and Hartree–Fock (TD-HF)
methods, electronic absorption spectra of the title compound have been predicted and a good agreement with the TD-DFT method
and experimental ones is determined. The energetic behavior of the title compound in solvent media has been examined using
B3LYP method with the 6−31G(d,p) basis set by applying the polarizable continuum model (PCM). The total energy of the title
compound decreases with increasing polarity of the solvent. In addition, DFT calculations of the title compound, molecular
electrostatic potential (MEP), natural bond orbital analysis (NBO), and non-linear optical (NLO) properties were performed
at B3LYP/6−31G(d,p) level of theory. 相似文献
188.
Invernale MA Pendergraph SA Yavuz MS Ombaba M Sotzing GA 《Journal of polymer science. Part A, Polymer chemistry》2010,48(9):2024-2031
Processability remains a fundamental issue for the implementation of conducting polymer technology. A simple synthetic route towards processable precursors to conducting polymers (main chain and side chain) was developed using commercially available materials. These soluble precursor systems were converted to conjugated polymers electrochemically in aqueous media, offering a cheaper and greener method of processing. Oxidative conversion in aqueous and organic media each produced equivalent electrochromics. The precursor method enhances the yield of the electrochromic polymer obtained over that of electrodeposition, and it relies on a less corruptible electrolyte bath. However, electrochemical conversion of the precursor polymers often relies on organic salts and solvents. The ability to achieve oxidative conversion in brine offers a less costly and a more environmentally friendly processing step. It is also beneficial for biological applications. The electrochromics obtained herein were evaluated for electronic, spectral, and morphological properties. 相似文献
189.
Mustafa Korkmaz 《Geometriae Dedicata》2002,89(1):107-131
We obtain a finite set of generators for the mapping class group of a nonorientable surface with punctures. We then compute the first homology group of the mapping class group and certain subgroups of it. As an application we prove that the image of a homomorphism from the mapping class group of a nonorientable surface of genus at least nine to the group of real-analytic diffeomorphisms of the circle is either trivial or of order two. 相似文献
190.
Alan R. Morgan Dimitris Skalkos George Maguire Ashraf Rampersaud Greta Garbo Rick Keck Steven H. Selman 《Photochemistry and photobiology》1992,55(1):133-136
An improved synthesis of benzochlorins is reported. Demetallation of the meso-hydroxymethylvinyl derivative of octaethylporphyrin, followed by treatment with sulfuric acid results in cyclization to generate the corresponding octaethylbenzochlorin in high yield. Prolonged treatment with acid generates the sulfonated derivative. These sensitizers were shown to be efficient photodynamic agents in vivo. Animals bearing a transplanted N-[4-(5-nitro-2-furyl)-2-thiazoly]formamide induced urothelial tumor were treated with either the benzochlorin or its sulfonated derivative. Irradiation of tumors 24 h later resulted in a significant tumoricidal effect in a short term assay. We conclude that benzochlorins warrant further examination as potential agents for use in photodynamic therapy. 相似文献