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121.
A simple,efficient,and general method has been developed for the synthesis ofα-amino nitriles.Oxalic acid as a BrФnsted acid promotes the addition of TMSCN to various imines(generated in situ). 相似文献
122.
In this work, a Sturm–Liouville‐type problem with retarded argument, which contains spectral parameter in the boundary conditions and with transmission conditions at the point of discontinuity are investigated. We obtained asymptotic formulas for the eigenvalues and eigenfunctions. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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125.
Muhammad Hunar Yasin Faizullah Azad Tawfiq 《Journal of the Iranian Chemical Society》2020,17(1):111-118
Journal of the Iranian Chemical Society - A simple and low-cost flow injection spectrophotometric method was proposed for the simultaneous determination of ascorbic acid (AA) and paracetamol (PCM)... 相似文献
126.
This is a case study of solving the Genesio system by using the classical variational iteration method (VIM) and a newly modified version called the multistage VIM (MVIM). VIM is an analytical technique that grants us a continuous representation of the approximate solution, which allows better information of the solution over the time interval. Unlike its counterpart, numerical techniques, such as the Runge–Kutta method, provide solutions only at two ends of the time interval (with condition that the selected time interval is adequately small for convergence). Furthermore, it offers approximate solutions in a discretized form, making it complicated in achieving a continuous representation. The explicit solutions through VIM and MVIM are compared with the numerical analysis of the fourth-order Runge–Kutta method (RK4). VIM had been successfully applied to linear and nonlinear systems of non-chaotic in nature and this had been testified by numerous scientists lately. Our intention is to determine whether VIM is also a feasible method in solving a chaotic system like Genesio. At the same time, MVIM will be applied to gauge its accuracy compared to VIM and RK4. Since, for most situations, the validity domain of the solutions is often an issue, we will consider a reasonably large time frame in our work. 相似文献
127.
A. S. Bataineh A. K. Alomari M. S. M. Noorani I. Hashim R. Nazar 《Acta Appl Math》2009,105(2):189-198
Differential equations of fractional order appear in many applications in physics, chemistry and engineering. An effective
and easy-to-use method for solving such equations is needed. In this paper, series solutions of the FDEs are presented using
the homotopy analysis method (HAM). The HAM provides a convenient way of controlling the convergence region and rate of the
series solution. It is confirmed that the HAM series solutions contain the Adomian decomposition method (ADM) solution as
special cases.
相似文献
128.
Narayanarao Gundoju Ramesh Bokam Nageswara Rao Yalavarthi Rajaram Azad 《Natural product research》2019,33(18):2618-2622
Chemical manipulation studies were conducted on betulinic acid (1), twenty-one new rationally designed analogues of 1 with modifications at C-28 were synthesized for their evaluation of inhibitory effects on α-glucosidase and LPS-stimulated nitric oxide production in mouse macrophage RAW 264.7 cells. Compound 2 (IC50 = 5.4 μM) exhibited an almost 1.4-fold increase in α-glucosidase inhibitory activity on yeast α-glucosidase while analogues 5 (IC50 16.4 μM) and 11 (IC50 16.6 μM) exhibited a 2-fold enhanced inhibitory activity on NO-production than betulinic acid. 相似文献
129.
The differential transformation method (DTM) is employed to solve a nonlinear differential equation, namely the Lorenz system. Numerical results are compared to those obtained by the Runge-Kutta method to illustrate the preciseness and effectiveness of the proposed method. In particular, we examine the accuracy of the (DTM) as the Lorenz system changes from a non-chaotic system to a chaotic one. It is shown that the (DTM) is robust, accurate and easy to apply. 相似文献
130.