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41.
smail Aslan 《理论物理通讯》2014,(5):595-599
The extended simplest equation method is used to solve exactly a new differential-difference equation of fractional-type, proposed by Narita [J. Math. Anal. Appl. 381 (2011) 963] quite recently, related to the discrete MKdV equation. It is shown that the model supports three types of exact solutions with arbitrary parameters: hyperbolic, trigonometric and rational, which have not been reported before. 相似文献
42.
We investigate the decay property of a Timoshenko system of thermoelasticity in the whole space for both Fourier and Cattaneo laws of heat conduction. We point out that although the paradox of infinite propagation speed inherent in the Fourier law is removed by changing to the Cattaneo law, the latter always leads to a solution with the decay property of the regularity‐loss type. The main tool used to prove our results is the energy method in the Fourier space together with some integral estimates. We derive L2 decay estimates of solutions and observe that for the Fourier law the decay structure of solutions is of the regularity‐loss type if the wave speeds of the first and the second equations in the system are different. For the Cattaneo law, decay property of the regularity‐loss type occurs no matter what the wave speeds are. In addition, by restricting the initial data to with a suitably large s and γ ∈ [0,1], we can derive faster decay estimates with the decay rate improvement by a factor of t?γ/2. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
43.
We present a method for the fabrication of PVTri-BaFe12O19 nanocomposites by in-situ polymerization of PVTri in the presence of synthesized BaFe12O19 nanoparticles. Nanoparticles, polymer and nanocomposite were analyzed by XRD, FTIR, TGA, TEM, NMR, GPC and conductivity techniques for structural and physicochemical characteristics. Crystallographic analysis revealed the phase as hexaferrite and X-ray line profile fitting yielded a crystallite size of 17±5 nm. Conjugation of PVTri to nanoparticle surface was assessed to be via carbonyl groups on the polymer. TG analysis revealed that 45 wt% of nanocomposite is inorganic phase (BaFe12O19). It was found out that the ac conductivity of nanocomposite under a certain frequency increases with temperature. 相似文献
44.
Alkyl bromoacetates were shown to be versatile transesterification reagents. Isoxazoles underwent chemoselective transesterification when treated with alkyl bromoacetate-Zn in THF at reflux. A suggested mechanism of the new reaction was discussed. 相似文献
45.
1,4-Diarylimidazoline 3-oxides react with N-arylmaleimides in benzene to give predominantly the corresponding endo adducts. Chiral imidazoline 3-oxides react diastereospecifically (cis configuration of the tetrahydroimidazo ring) and diastereoselectively to give cis-endo adducts. The effects of substituents on the aromatic ring of the maleimide was investigated. The presence of electron-withdrawing or releasing groups have minor effect on the total yields but more pronounced is the effect on the ratio of exo and endo diastereomers. The adducts undergo an interesting and unprecedented ring-opening in the presence of secondary amines to give deoxygenated 3-imidazoline 3-oxides instead of the expected double cis elimination products. Tertiary amines did not induce any reaction. 相似文献
46.
Numerical solutions of liquid metal flows by incompressible magneto‐hydrodynamics with heat transfer
A two‐dimensional incompressible magneto‐hydrodynamic code is presented in order to solve the steady state or transient magnetized or neutral convection problems with the effect of heat transfer. The code utilizes a numerical matrix distribution scheme that runs on structured or unstructured triangular meshes and employs a dual time‐stepping technique with multi‐stage Runge–Kutta algorithm. The code can be used to simulate the natural convection with internal heat generation and absorption and nonlinear time‐dependent evolution of heated and magnetized liquid metals exposed to external fields. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
47.
We describe a novel platform technology for both significantly enhancing and obtaining chemiluminescence signatures "on-demand", subsequently named Microwave-Triggered Metal-Enhanced Chemiluminescence. By combining the use of silver nanoparticles to plasmon enhance chemiluminescence with the use of low power microwaves to localize heating around the nanostructures, we can both optically amplify and trigger chemiluminescence reactions. This approach is a significant advantage over traditional chemiluminescence techniques and methodologies, such as those used for Western Blots, which typically require long periods of time to collect chemiluminescence and offer few possibilities of optically amplifying the signatures. 相似文献
48.
49.
We have performed first-principles method to investigate structural and electronic properties of InNxP1?x ternary semiconductor alloy in full range (0 ≤ x ≤ 1) using density functional theory. We have used modified Becke–Johnson potential to obtain accurate band gap results. From the electronic band structure calculation we have found that InNxP1?x become metal between 47 and 80% of nitrogen concentration. Additional to our band gap calculations, we have also used the band anticrossing model. The band anticrossing model supplies a simple, analytical expression to calculate the physical properties, such as the electronic and optical properties, of III-NxV1?x alloys. The knowledge of the electron density of states is required to understand and clarify some properties of materials such as the band structures, bonding character and dielectric function. In order to have a deeper understanding of these properties of the studied materials, the total and partial density of states has been calculated. Finally, we have calculated the total bowing parameter b of studied alloys, together with three contributions bVD, bCE, and bSR due to volume deformation, different atomic electron negativities and structural relaxation, respectively. 相似文献
50.