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101.
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
102.
Vagif Sabir Guliyev Turhan Karaman Rza Chingiz Mustafayev Ayhan Şerbetçi 《Czechoslovak Mathematical Journal》2014,64(2):365-386
In this paper, the boundedness of a large class of sublinear commutator operators T b generated by a Calderón-Zygmund type operator on a generalized weighted Morrey spaces \({M_{p,\varphi }}(w)\) with the weight function w belonging to Muckenhoupt’s class A p is studied. When 1 < p < ∞ and b ∈ BMO, sufficient conditions on the pair (φ 1, φ 2) which ensure the boundedness of the operator T b from \({M_{p,\varphi 1}}(w)\) to \({M_{p,\varphi 2}}(w)\) are found. In all cases the conditions for the boundedness of T b are given in terms of Zygmund-type integral inequalities on (φ 1, φ 2), which do not require any assumption on monotonicity of φ 1(x, r), φ 2(x, r) in r. Then these results are applied to several particular operators such as the pseudo-differential operators, Littlewood-Paley operator, Marcinkiewicz operator and Bochner-Riesz operator. 相似文献
103.
A collocation method based on the Bessel functions of the first kind for singular perturbated differential equations and residual correction 下载免费PDF全文
Şuayip Yüzbaşı 《Mathematical Methods in the Applied Sciences》2015,38(14):3033-3042
In this paper, a collocation method is given to solve singularly perturbated two‐point boundary value problems. By using the collocation points, matrix operations and the matrix relations of the Bessel functions of the first kind and their derivatives, the boundary value problem is converted to a system of the matrix equations. By solving this system, the approximate solution is obtained. Also, an error problem is constructed by the residual function, and it is solved by the presented method. Thus, the error function is estimated, and the approximate solutions are improved. Finally, numerical examples are given to show the applicability of the method, and also, our results are compared by existing results. Copyright © 2014 JohnWiley & Sons, Ltd. 相似文献
104.
Yusuf Akbaba Halis Türker Balaydın Süleyman Göksu Ertan Şahin Abdullah Menzek 《Helvetica chimica acta》2010,93(6):1127-1135
3,4‐Dibromo‐5‐[2‐bromo‐3,4‐dihydroxy‐6‐(methoxymethyl)benzyl]benzene‐1,2‐diol ( 2 ), a natural product, has been synthesized for the first time starting from (3‐bromo‐4,5‐dimethoxyphenyl)methanol ( 5 ) in five steps and with an overall yield of 34%. The reaction of some methoxymethyl‐substituted aryl methyl ethers with BBr3, followed by the addition of MeOH, afforded the corresponding methoxymethyl‐substituted arylphenols in high yields. 相似文献
105.
(3,4-Dimethoxyphenyl)(2,3,4-trimethoxyphenyl)methanone was synthesized and its bromination was investigated in different conditions. Nine new products (bromophenol derivatives) were isolated in the reactions. These bromophenol derivatives were obtained by selective O-demethylation in its bromination with bromine. The products and their formations were discussed. 相似文献
106.
Synthesis and proton conductivity studies of polystyrene‐based triazole functional polymer membranes
Şehmus Özden Sevim Ünügür Çelik Ayhan Bozkurt 《Journal of polymer science. Part A, Polymer chemistry》2010,48(22):4974-4980
In this study, poly(vinylbenzylchloride) (PVBC) was produced by free‐radical polymerization of 4‐vinylbenzylchloride, and then it was functionalized with 3‐amino‐1,2,4‐triazole (ATri) and 1H‐1,2,4‐triazole (Tri). The composition of the polymers was verified by elemental analysis, and the structure was characterized by Fourier transform infrared and 13C‐nuclear magnetic resonance spectra. PVBC was modified by ATri with 68% and Tri with 50% yield. The polymers were doped with trifluoromethanesulfonic acid (TA) at various molar ratios, X = 0.5, 1, 2, and 3 with respect to aminotriazole and triazole units. Proton transfer from TA to the triazole rings was proved with Fourier transform infrared spectroscopy. Thermogravimetric analysis showed that the samples are thermally stable up to approximately 200 °C. Differential scanning calorimetry results illustrated the homogeneity of the materials. Under anhydrous conditions, PVBCATri3TA and PVBCTri3TA showed highest proton conductivity of 0.086 and 0.042 S/cm, respectively. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
107.
Ülkü Yılmaz Hasan Küçükbay Nihat Şireci Mehmet Akkurt Selami Günal Rıza Durmaz M. Nawaz Tahir 《应用有机金属化学》2011,25(5):366-373
A mixture of benzimidazole salts (2–7), Pd(OAc)2 and K2CO3 in DMF–H2O catalyzes the Suzuki–Miyaura cross‐coupling reactions promoted by microwave irradiation resulting in high yield within a short time. In particular, the yield of the Suzuki–Miyaura reactions with aryl bromides was found to be nearly quantitative. The synthesized benzimidazole salts (2–7) were identified by 1H‐13C, NMR, IR spectroscopic methods and microanalysis. The molecular structure of 1 was determined by X‐ray crystallography. The antibacterial and antifungal activities of the novel benzimidazole derivatives (1–7) were also tested against standard strains. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
108.
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110.
Ni(II) and Zn(II) complexes of the bidentate thiol ligand N-trans-cinnamylidene-2-mercaptoaniline which is obtained from trans-cinnamaldehyde and 2-mercaptoaniline were prepared and characterized by their IR absorption spectra, X-ray powder diffraction measurements, elemental analysis and 1H-NMR spectra. On the other hand, energy minimization studies of the molecules were carried out to obtain the most probable three-dimensional molecular conformations.The comparative 1H-NMR, IR, X-ray powder diffraction and energy minimization studies have shown that metal atoms are connected to the N and S atoms of Schiff bases and the complex have cis type fashion. 相似文献