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991.
K. Drożdżewska A. Książczak T. Książczak 《Journal of Thermal Analysis and Calorimetry》2000,60(1):103-110
Cyanazine was taken as an example for investigations under the influence of different conditions on thermal decomposition
of triazine herbicides. DSC measurements were carried out under atmospheric pressure and hermetically closed, under pressure
1.3 kPa. The influence of the pressure on the constant reaction rate of decomposition of cyanazine was discussed. It was also
proved that the predicted reaction constant rates from isothermal and non-isothermal measurements are consistent.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
992.
O. D. Makinde 《国际流体数值方法杂志》2009,59(7):791-799
In this paper, the temporal development of small disturbances in a pressure‐driven fluid flow through a channel filled with a saturated porous medium is investigated. The Brinkman flow model is employed in order to obtain the basic flow velocity distribution. Under normal mode assumption, the linearized governing equations for disturbances yield a fourth‐order eigenvalue problem, which reduces to the well‐known Orr–Sommerfeld equation in some limiting cases solved numerically by a spectral collocation technique with expansions in Chebyshev polynomials. The critical Reynolds number Rec, the critical wave number αc, and the critical wave speed cc are obtained for a wide range of the porous medium shape factor parameter S. It is found that a decrease in porous medium permeability has a stabilizing effect on the fluid flow. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
993.
994.
Zinc finger domains consist of sequences of amino acids containing cysteine and histidine residues tetrahedrally coordinated
to a zinc ion. The role of zinc in a DNA binding finger was considered purely structural due to the absence of redox chemistry
in zinc. However, whether other metals e.g. Co(II) or Cd(II) can substitute Zn(II) is not settled. For an answer the detailed
interaction of Co(II) and Cd(II) with cysteine methylester and histidine methylester has been investigated as a model for
the zinc core in zinc fingers. The study was extended to different temperatures to evaluate the thermodynamic parameters associated
with these interactions. The results suggest that zinc has a unique role. 相似文献
995.
996.
Jiaowan Luo 《Journal of Mathematical Analysis and Applications》2008,342(2):753-760
The fixed-point theory is first used to consider the stability for stochastic partial differential equations with delays. Some conditions for the exponential stability in pth mean as well as in sample path of mild solutions are given. These conditions do not require the monotone decreasing behavior of the delays, which is necessary in [T. Caraballo, K. Liu, Exponential stability of mild solutions of stochastic partial differential equations with delays, Stoch. Anal. Appl. 17 (1999) 743-763; Ruhollan Jahanipur, Stability of stochastic delay evolution equations with monotone nonlinearity, Stoch. Anal. Appl. 21 (2003) 161-181]. Even in this special case, our results also improve the results in [T. Caraballo, K. Liu, Exponential stability of mild solutions of stochastic partial differential equations with delays, Stoch. Anal. Appl. 17 (1999) 743-763]. 相似文献
997.
In the paper we study the existence of solutions of a nonlinear quadratic Volterra integral equation of fractional order. This equation is considered in the Banach space of real functions defined, continuous and bounded on an unbounded interval. Moreover, we show that solutions of this integral equation are locally attractive. 相似文献
998.
Using the Riesz basis approach, we study a sandwich beam that is composed of an outer stiff layer and a compliant middle layer.
The dynamic behavior and analyticity of the system are obtained based on a detailed spectral analysis and Riesz basis generation.
As a consequence, the analyticity of the solution and the exponential stability of the system are concluded.
This work was supported by the National Natural Science Foundation of China, Program for New Century Excellent Talents in
the Universities of China and by the National Research Foundation of South Africa. 相似文献
999.
In this paper, we present an analysis for the class of delay differential equations with one discrete delay and the right‐hand side depending only on the past. We extend the results from paper by U. Fory? (Appl. Math. Lett. 2004; 17 (5):581–584), where the right‐hand side is a unimodal function. In the performed analysis, we state more general conditions for global stability of the positive steady state and propose some conditions for the stable Hopf bifurcation occurring when this steady state looses stability. We illustrate the analysis by biological examples coming from the population dynamics. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
1000.
就一类高阶时滞Cohen-Grossberg社昆网络进行研究,假设反应函数满足Lipschitz连续且有界,用非线性测度的方法得到了关于平衡点的存在性和惟一性的一种新的充分性的判别条件,同时,通过构造一个合适的Lyapunov函数,得到这个条件也保证了时滞神经网络的全局指数稳定性. 相似文献