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981.
Thermodynamic properties and phase diagrams of a mixed spin-(1,2) Ising ferrimagnetic system with single ion anisotropy on hexagonal nanowire are studied by using effective-field theory with correlations. The susceptibility, internal energy and specific heat of the system are numerically examined and some interesting phenomena in these quantities are found. The effect of the Hamiltonian parameters on phase diagrams are examined in detail. Besides second-order phase transition, lines of first-order transition and tricritical points are found. In particular, we found that for some negative values of single-ion anisotropies, there exist first-order phase transitions. 相似文献
982.
Thomas Altazin Mehmet Ersoy Damien Sous Lyudmyla Yushchenko 《International Journal of Computational Fluid Dynamics》2016,30(3):256-271
In this work, a parallel finite volume scheme on unstructured meshes is applied to fluid flow for multidimensional hyperbolic system of conservation laws. It is based on a block-based adaptive mesh refinement strategy which allows quick meshing and easy parallelisation. As a continuation and as an extension of a previous work, the useful numerical density of entropy production is used as mesh refinement criterion combined with a local time-stepping method to preserve the computational time. Then, we numerically investigate its efficiency through several test cases with a confrontation with exact solution or experimental data. 相似文献
983.
Ömer Ünsal Ahmet Bekir Filiz Taşcan Mehmet Naci Özer 《Waves in Random and Complex Media》2017,27(1):117-128
In this study, we obtain complexiton solutions of Sawada–Kotera equation and ninth-order KdV equation. For this cause, we employ Wazwaz and Zhaqilao’s method which can be regarded as generalization of simplified Hirota method through extension real parameters into complex parameters. Special conditions to distinguish complexiton, soliton, and soliton–complexiton interaction solutions from each other are given. 相似文献
984.
Meric Yucel Serdar Bagis Ahmet Sertbas Mehmet Sarikaya Burak Berk Ustundag 《Entropy (Basel, Switzerland)》2022,24(11)
Highlights What are the main findings?
- A cortical coding method is developed inspired by the network formation in the brain, where the information entropy is maximized while dissipated energy is minimized.
- The execution time in the cortical coding model is far superior, seconds versus minutes or hours, compared to those of the frequently used current algorithms, while retaining comparable distortion rate.
- The significant attribute of the methodology is its generalization performance, i.e., learning rather than memorizing data.
- Although only vector quantization property was demonstrated herein, the cortical coding algorithm has a real potential in a wide variety of real-time machine learning implementations such as , temporal clustering, data compression, audio and video encoding, anomaly detection, and recognition, to list a few.
985.
Enhanced methods of drug monitoring are required to support the individualization of therapeutic drug dosing. Clozapine is one of the most important medications for managing schizophrenia, and timely measurement of serum clozapine levels has been identified as a barrier to the broader use of clozapine. For the first time, reduced graphene oxide nanocomposites were used to construct an electrochemical clozapine (Clz) sensor. The Reduced graphene oxide (Rego) nanocomposites were synthesized and characterized by using X-Ray Diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM) techniques. The Clz sensing electrode was fabricated by drop coating of Rego nanocomposites suspension and Nafion solution on the pencil graphite electrode, respectively. The electrochemical behavior and influence of various physicochemical parameters of sensing electrodes were investigated by using cyclic voltammetry (CV) and differential voltammetry (DPV) techniques. The designed sensor displayed decent linear range, detection limit, reproducibility, and reusability results. Under optimum experimental parameters a linear dynamic range of 0.05–10 μM clozapine was observed with actual detection limit of 50 nM. Furthermore, the designed sensing electrode was used to measure the amount of Clz in real samples. 相似文献
986.
Mehmet Kabak Hülya ?en?z Ayhan Elmali Vildan Adar Ingrid Svoboda Michal Du?ek Karla Fejfarová 《Crystallography Reports》2010,55(7):1220-1222
The title compound, C29H23NO2, has been characterized by single-crystal X-ray diffraction at two different temperatures (303 K and 120 K) and wavelengths (MoK α and CuK α). The non-centrosymmetric hexagonal crystal structure contains four-membered planar β-lactam ring with an unusually long C-C bond. The β-lactam ring is almost planar. 相似文献
987.
Tabak Ahmet Sevimli Kadir Kaya Mehmet Çağlar Bülent 《Journal of Thermal Analysis and Calorimetry》2019,138(6):3885-3895
Journal of Thermal Analysis and Calorimetry - The novel activated carbon materials were synthesized by the carbonization and chemical activation of agricultural bio-waste from tea woody stems... 相似文献
988.
Mustafa Ciftci Mehmet Atilla Tasdelen 《Journal of polymer science. Part A, Polymer chemistry》2020,58(3):412-416
The synthesis of polysulfone (PSU) graft copolymers by a two-step “grafting from” approach is described. First, a chlorofunctional PSU (PSU-Cl) is formed via chloromethylation of a commercial PSU. The formed polymers are used macroinitiator for the dimanganese decacarbonyl assisted free-radical polymerization of tert-butyl acrylate, methyl methacrylate, and styrene to give the desired graft copolymers. Moreover, amphiphilic graft copolymers are also formed via posthydrolyzation of poly(tert-butyl acrylate) containing graft copolymers. The intermediates at various stages and the ultimate graft copolymers are characterized by various analysis techniques. © 2020 Wiley Periodicals, Inc. J. Polym. Sci. 2020 , 58, 412–416 相似文献
989.
A high power enzymatic fuel‐cell was anticipated by using a recently developed glucose oxidase (GOx) immobilized bio‐anode, a conventional platinum?carbon based cathode and a popular high performance 125 μ‐thick perfluorosulfonic acid‐type proton exchange membrane (i. e. Nafion® 115). Unexpected current density decay from 2.13 mA cm?2 to 0.28 mA cm?2 was observed within 2 hours. Polarization measurements and AC impedance analysis indicated that loss of performance was linked to the membrane behavior. Ion exchange between buffer solution and membrane was perceived as the main cause for the fast performance loss. Saturation of the membrane with the cation in the buffer solution diminished proton transfer needed for cathode reaction. Charge transfer resistances, obtained from AC impedance data, increased with time substantially due to cation exchange within membrane. Replacement of membrane with the same enzyme electrode and cathode has resulted 100 % current density recovery on the fuel cell performance. It was concluded that a membrane, not affected by the buffer cations, was required for successful enzymatic fuel cell applications. 相似文献
990.
Eratr Mehmet Yldrm Metin Giray Elife Sultan Yaln Serap 《Monatshefte für Chemie / Chemical Monthly》2020,151(4):625-636
Monatshefte für Chemie - Chemical Monthly - A series of novel coumarins with 2-amino-3-cyanoselenophen-5-yl unit on C-3 have been synthesized. These compounds prepared easily at room... 相似文献