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101.
In the present paper, some types of general solutions of a first-order nonlinear ordinary differential equation with six degree are given and a new generalized algebra method is presented to find more exact solutions of nonlinear differential equations. As an application of the method and the solutions of this equation, we choose the (2 + 1) dimensional Boiti Leon Pempinelli equation to illustrate the validity and advantages of the method. As a consequence, more new types and general solutions are found which include rational solutions and irrational solutions and so on. The new method can also be applied to other nonlinear differential equations in mathematical physics. 相似文献
102.
103.
104.
Sanzhizhapov D. B. Tonevitskii Yu. V. Mognonov D. M. Doroshenko Yu. E. 《Russian Journal of Applied Chemistry》2003,76(4):619-622
New polyimidates were prepared from bisphenols and mono- and dicarboxylic acid imidoyl chlorides. The structures of the polymers were determined, and their physicochemical, chemical, and thermal properties were studied. The possibility of preparing film and compression materials with good mechanical characteristics from these polymers was examined. 相似文献
105.
D. Shakin 《Journal of Mathematical Sciences》2007,142(4):2302-2366
In this paper, we study the numeric characteristics (the Hilbert function and graded Betti numbers) of monomial ideals in
the polynomial ring and in the exterior algebra.
__________
Translated from Sovremennaya Matematika i Ee Prilozheniya (Contemporary Mathematics and Its Applications), Vol. 30, Algebra,
2005. 相似文献
106.
For the linear deterministic system with unknown orders and coefficients adaptive controls are given so that the closed-loop system is stabilized and the unknown parameters are consistently estimated. Moreover, if the parameter estimation is ignored, then the system input and output can be reduced to zero with an exponential rate.This project is supported by the National Natural Science Foundation of China.In Commemoration of the 15th Anniversary of the Acta Mathematicae Applicatae Sinica. 相似文献
107.
108.
109.
An integrated study of diffusion, solubility, and electrical properties of scandium and praseodymium in silicon annealed in
various media and temperature ranges (1100–1280 °C) was performed for the first time. The tracer technique, autoradiography,
measurements of isothermic capacity and current relaxation, conductivity, and the Hall effect were used for the investigations.
The diffusion parameters, solubility, and an acceptor character of scandium and praseodymium impurities in silicon were determined.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 75–77, January, 2007. 相似文献
110.
本文报道了用吸附溶出伏安法测定毗喳酮.以悬汞电极为工作电极,在Na}B,O,-NaOH介质(pH=10)中,毗喳酮产生一尖锐的吸附还原峰,E,二一1. 29V (vs. SCE ),峰电流与毗喳酮浓度在2. 0 X 10-'-8. 0 X 10-smol " L-’范围内呈良好的线性关系.检测限为2. 0 X 10-0mol " L-'(富集90s).本文对毗喳酮在悬汞电极上的电化学行为进行了探讨,对测定毗喳酮的最佳条件进行了详细的选择,利用本法测定了片剂中毗喳酮含量,结果满意. 相似文献