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91.
The sandwiched trilayer of Bethe lattices in the form of the spins with spin-(1/2,1,1/2) Ising model is studied in terms of the recursion relations with either ferromagnetic or antiferromagnetic type bilinear interactions between the nearest-neighbor (NN) spins. The ground-state (GS) phase diagrams are obtained and it was found that the model presents six different GS phase configurations. In order to obtain the phase diagrams, the thermal variations of the order-parameter, spin-spin correlation functions and free energy are analyzed and different topological phase diagrams are obtained. It was found that the system exhibits different critical behaviors such as, second- and first-order phase transitions, tricritical and bicritical points for the values of the coordination numbers q=3,4 and 6. 相似文献
92.
Nasser-eddine M. Tatar 《Journal of Applied Analysis & Computation》2017,7(4):1267-1274
A strongly damped wave equation involving a delay of neutral type in its second order derivative is considered. It is proved that solutions decay to zero exponentially despite the fact that delays are, in general, sources of instability. 相似文献
93.
A simple, precise and sensitive spectrofluorimetric method was developed and validated for the determination of ranitidine in pharmaceutical preparations. The method is based on derivatization of ranitidine with 4-fluoro-7-nitrobenzofurazan (NBD-F). The method was successfully validated in accordance to ICH guidelines. The validation characteristics included linearity, limit of detection, limit of quantification, accuracy, precision, specificity and robustness. The method is linear over the range of 40?C1200 ng/mL. The recoveries were ranged from 98.97 to 99.43%. The proposed method was applied for the determination of ranitidine in commercially available tablets. The results were compared with those obtained by reference method using t and F-tests. 相似文献
94.
Optics and Spectroscopy - A simple, accurate and highly sensitive spectrofluorimetric method has been developed for determination of nizatidine in pure form and in pharmaceutical dosage forms. The... 相似文献
95.
Maryam Ahmadian-Moghaddam Monire Tatar 《Phosphorus, sulfur, and silicon and the related elements》2017,192(5):481-484
A series of new N-acetyl/thioacetyl-(E)-stilbene benzenesulfonamide derivatives were synthesized regioselectively in moderate to high yields by following a convenient, three-step procedure. The procedure consists of the direct oxidative conversion of a thiol compound to the corresponding sulfonyl chloride using TMSCl/KNO3, followed by a room temperature reaction in a one-pot transformation of the resultant sulfonyl chloride into N-acetyl/thioacetyl sulfonamide, which undergoes a further Pd-catalyzed coupling reaction, giving rise to the stilbene compounds reported for the first time. 相似文献
96.
Omer Kaygili Serhat Keser Cengiz Tatar Suleyman Koytepe Tankut Ates 《Journal of Thermal Analysis and Calorimetry》2017,128(2):765-770
A glass with the composition of the SiO2–Na2O–CaO–P2O5 was synthesized by sol–gel method at temperature of 900 °C, and then yttrium-, silver- and cerium-containing glasses were prepared at the same conditions using this base system. The structural and thermal properties of the glass samples were investigated by X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy, energy-dispersive X-ray (EDX) spectroscopy and differential thermal analysis techniques. The Ca5(PO4)2(SiO4)6 phase having the orthorhombic crystal system is detected for each sample without any secondary phase, and this phase is confirmed by the FTIR spectra. With the addition of Y, Ag and Ce to the SiO2–Na2O–CaO–P2O5 system, the variations in the average crystallite size, crystallinity percent, lattice parameters and unit cell volume are observed. A decrease in the crystallization peak temperature and the changes in the glass transition temperature are seen with the addition of Y, Ag and Ce to the base system. The addition of Y, Ag and Ce to the base glass increases significantly its density. The EDX spectra of the as-prepared samples verify the introduction of the as-mentioned elements. 相似文献
97.
Amirouche Berkani Nasser‐eddine Tatar Ammar Khemmoudj 《Mathematical Methods in the Applied Sciences》2017,40(1):237-254
In this paper, we study a cantilevered Euler–Bernoulli beam fixed to a base in a translational motion at one end and to a tip mass at its free end. The beam is subject to undesirable vibrations, and it is made of a viscoelastic material that permits a certain weak damping. By applying a control force at the base, we shall attenuate these vibrations in a fast manner. In fact, we establish the exponential stability of the system. Our method is based on the multiplier technique. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
98.
O. Kaygili C. Tatar F. Yakuphanoglu S. Keser 《Journal of Sol-Gel Science and Technology》2013,65(2):105-111
The hydroxyapatite and hydroxyapatite-based bioceramics with high Al contents were synthesized using sol–gel method, and their characterization was carried out by X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy. With the increase of Al content, the crystallinity is dramatically decreased, and the phase structure belonging to hydroxyapatite was transformed into the new phases, including aluminum calcium phosphate and/or aluminum phosphate. The average crystallite size of the bioceramic samples was found to be in the range of 10–50 nm. FTIR spectroscopy results verified the presence of various $ {\text{PO}}_{4}^{3 - } $ and $ {\text{OH}}^{ - } $ groups in the samples. The density value of the samples significantly increased with the addition of Al. It is evaluated that hydroxyapatite bioceramic can be converted to new bioceramics with high Al contents. 相似文献
99.
Bahadir AO Balcioglu BK Uzyol KS Hatipoglu I Sogut I Basalp A Erdag B 《Applied biochemistry and biotechnology》2011,165(7-8):1437-1447
Hepatitis B is a major public health problem worldwide, which may lead to chronic liver diseases such as cirrhosis and hepatocellular carcinoma. The hepatitis B core antigen (HBcAg) is one of the major viral proteins, which forms the inner core of hepatitis B virus (HBV) particles. In this study, filamentous bacteriophage M13 was genetically modified to display the polypeptides of HBcAg in order to develop an alternative carrier system. HBcAg gene was inserted into the minor coat protein (pIII) gene of M13, and HBcAg was expressed on the phage surface as a whole protein. Antigenicity and immunogenicity of HBcAg were tested by immunizing BALB/c mice three times with HBcAg-displaying recombinant phages. After successful immunization, one of the mice with high antibody titer to HBcAg was selected for fusion, and four monoclonal antibodies specific for HBcAg were developed. This result showed that HBcAg-displaying recombinant bacteriophages are immunogenic and can potentially be used for the development of monoclonal antibodies. 相似文献
100.