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81.
Analytical solutions for the Cahn-Hilliard initial value problem are obtained through an application of the homotopy analysis method. While there exist numerical results in the literature for the Cahn-Hilliard equation, a nonlinear partial differential equation, the present results are completely analytical. In order to obtain accurate approximate analytical solutions, we consider multiple auxiliary linear operators, in order to find the best operator which permits accuracy after relatively few terms are calculated. We also select the convergence control parameter optimally, through the construction of an optimal control problem for the minimization of the accumulated L 2-norm of the residual errors. In this way, we obtain optimal homotopy analysis solutions for this complicated nonlinear initial value problem. A variety of initial conditions are selected, in order to fully demonstrate the range of solutions possible. 相似文献
82.
Georges Assaf Gemma Cansell Doug Critcher Stuart Field Stewart Hayes Suju Mathew Alan Pettman 《Tetrahedron letters》2010,51(38):5048-5051
We report our results on the construction of a morpholine ring system from the corresponding epoxide and amino alcohol. From this study, we were able to convert a previous four-step synthesis into a more efficient two-step process. 相似文献
83.
The synthesis of alkyl-substituted 2-pyrrolecarboxylate esters has been accomplished by the condensation reaction of a symmetrical vinamidinium salt and glycine ester derivatives. 相似文献
84.
We complete the computation of spectral measures for SU(3) nimrep graphs arising in subfactor theory, namely the SU(3) ADE{SU(3) \mathcal{ADE}} graphs associated with SU(3) modular invariants and the McKay graphs of finite subgroups of SU(3). For the SU(2) graphs the spectral measures distill onto very special subsets of the semicircle/circle, whilst for the SU(3) graphs the spectral measures distill onto very special subsets of the discoid/torus. The theory of nimreps allows us to
compute these measures precisely. We have previously determined spectral measures for some nimrep graphs arising in subfactor
theory, particularly those associated with all SU(2) modular invariants, all subgroups of SU(2), the torus
\mathbbT2, SU(3){\mathbb{T}^2,\,SU(3)}, and some SU(3) graphs. 相似文献
85.
Jolly Andrews Vincent Mathew 《Physica C: Superconductivity and its Applications》2011,471(11-12):338-343
A high transition temperature superconducting microstrip structure is modeled using the theoretical approach developed by Coffey and Clem for elucidating the vortex effects in propagation. Impedance type Green’s functions are derived for the electric field around the strip and the propagation characteristics are computed for a wide range of applied field, reduced temperature and superconducting strip thickness in a Galerkin procedure. The increase of static field and temperature result in increased vortex motion, which in turn, causes a corresponding change in the propagation characteristics of the transmission line. Numerical results are presented for propagation parameters and quality factor. 相似文献
86.
Abstract Application of the method of orthogonal collocation to boundary value problems in structural and applied mechanics is investigated. Typical boundary value problems, such as the torsion of rectangular bars and the bending of plates, are employed as illustrative examples. Simplicity in application and good accuracy of orthogonal collocation are demonstrated by the solution of such complex problems as the large deflection analysis of rectangular isotropic, orthotropic, and sandwich plates. Results are compared wherever possible with existing solutions based on much more laborious and lengthy methods of computation. Excellent agreements are obtained. 相似文献
87.
Mathew W.C. Robinson 《Tetrahedron》2010,66(43):8377-8382
Epoxides undergo a highly efficient Meinwald rearrangement in the presence of catalytic quantities of copper(II) tetrafluoroborate to give carbonyl compounds in high yields and with excellent selectivity. The low toxicity and ease of handling of this reagent make it an attractive alternative to the more corrosive or costly Lewis acids frequently employed. 相似文献
88.
Weimin Zhang Fossum J.G. Mathew L. Yang Du 《Electron Devices, IEEE Transactions on》2005,52(10):2198-2206
Important physical insights regarding the design and performance of independent-gate FinFETs, e.g., the MIGFET , are gained from measured data and predictions from our process/physics-based double-gate (DG) MOSFET model (UFDG) in Spice3. Inversion charge-centroid shifting, modulated by gate biases as well as by quantum-confinement and short-channel effects, underlies the sensitivity of the MIGFET (front-gate) threshold voltage to the back-gate bias. MIGFET design and operation-mode options are examined for optimizing circuit applications. Further, novel design of a single-device RF mixer and a double-balanced counterpart using MIGFETs is studied with UFDG/Spice3. Reasonably good MIGFET mixers, with regard to conversion gain and linearity with small-size/low-voltage/low-power requirements, can be achieved with optimal biases on the two gates and good design of the MIGFET structure. 相似文献
89.
Thomas Mathew C. P. Joshua 《Journal of photochemistry and photobiology. A, Chemistry》1991,60(3):319-324
The photolysis of 2,2′-dinitrodiphenylmethylbenzoates (1a–1d) in 2-propanol gives dibenzo-[c, f]-[1,2]diazepin-11-one-oxides (5a–5d) as the major product. Dibenzo[c, f]-[1,2]diazepin-11-ones (2a–2d), 2,2′-dinitrobenzophenones (3a–3d), 2-amino-2′-nitrobenzophenones (4a–4d) and N-hydroxyacridones (6a–6d) are also formed in the reaction. When the irradiation is carried out in benzene, 3-(2′-nitrophenyl)-2,1-benzisoxazoles (7a–7d) are also obtained together with the above products. 相似文献
90.