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651.
Elisey Mazilov Evgeniya Ogurtsova Alexander Shamov Grigorii Khrapkovskii 《International journal of quantum chemistry》2010,110(4):939-945
Using nonempirical methods and DFT‐methods the geometrical parameters formation enthalpies of molecules and radicals, energies dissociation of N? NO2 bonds of primary and secondary N‐nitramines have been investigated. The basic tendencies in the changes of the geometrical and electronic structures, formation enthalpies, and dissociation energies have been analyzed in basic homologous series of nitramines. Various alternative mechanisms of the gas‐phase monomolecular thermal decomposition have been studied by of the example of N‐methylnitramine. The process of the aci‐form formation and its further multistage destruction is the most advantageous way of decomposition of the primary N‐nitramines. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 相似文献
652.
J. C. Motta Ferreira 《代数通讯》2013,41(9):3209-3216
In this article we prove that, if (U, ω) is a finite dimensional baric algebra of (γ, δ) type over a field F of characteristic ≠ 2,3,5 such that γ2 ? δ2 + δ = 1 and δ ≠ 0,1, then rad(U) = R(U) ∩ (bar(U))2, where R(U) is the nilradical (maximal nil ideal) of U. 相似文献
653.
Donal O’Regan 《Applicable analysis》2013,92(8):1674-1690
In this paper, we present new continuation theorems for maps in a very general class. 相似文献
654.
We consider the non‐local singular boundary value problem (1) where q ∈ C0([0,1]) and f, h ∈ C0((0,∞)), limf(x)=?∞, limh(x)=∞. We present conditions guaranteeing the existence of a solution x ∈ C1([0,1]) ∩ C2((0,1]) which is positive on (0,1]. The proof of the existence result is based on regularization and sequential techniques and on a non‐linear alternative of Leray–Schauder type. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
655.
Cui-Ping Cheng Wan-Tong Li Zhi-Cheng Wang 《Nonlinear Analysis: Real World Applications》2012,13(4):1873-1890
In this paper, we study the existence of traveling waves of a delayed population model with age-structure on a 2-dimensional spatial lattice when the maturation time r is relatively small. Under the assumption that the birth function b satisfies the bistable condition without requiring monotonicity, we prove the persistence of traveling wavefronts by means of a perturbation argument based on the existing results on the asymptotic autonomous system and the Fredholm alternative theory. 相似文献
656.
657.
Lourdes Gómez-Valle Miguel Ángel López-Marcos Julia Martínez-Rodríguez 《Mathematical Methods in the Applied Sciences》2020,43(14):7993-8005
In this paper, we consider a two-factor interest rate model with stochastic volatility, and we assume that the instantaneous interest rate follows a jump-diffusion process. In this kind of problems, a two-dimensional partial integro-differential equation is derived for the values of zero-coupon bonds. To apply standard numerical methods to this equation, it is customary to consider a bounded domain and incorporate suitable boundary conditions. However, for these two-dimensional interest rate models, there are not well-known boundary conditions, in general. Here, in order to approximate bond prices, we propose new boundary conditions, which maintain the discount function property of the zero-coupon bond price. Then, we illustrate the numerical approximation of the corresponding boundary value problem by means of an alternative direction implicit method, which has been already applied for pricing options. We test these boundary conditions with several interest rate pricing models. 相似文献
658.
Marcin Borkowski Dariusz Bugajewski 《Journal of Mathematical Analysis and Applications》2010,367(2):464-475
The aim of this paper is to prove a collection of fixed-point theorems for mappings which can be roughly called generalized contractions or their perturbations. In particular, we are going to consider operators (single-valued or multi-valued) in Banach spaces with a quasimodulus, in hyperconvex subsets of normed spaces, or finally in non-Archimedean spaces. A particular attention will be paid to Krasnoselskii-type fixed-point theorems as well as to a Schaefer-type fixed-point theorem. Some applications to nonlinear functional-integral equations will be given. Our results extend and complement some commonly known theorems. 相似文献
659.
1前言目前广泛使用的制冷工质R12,由于其对臭氧层的破坏,从96年起已被禁用。因为现有成熟的优良制冷工质R22具有很低的ODP值,而被公认为是近期良好过渡替代工质,并已证实十分适用于我国航运业。作者在制冷工质试验装置上,基于采用变频调速技术以R22替代R12模拟运行,并同时采用自制的喷射液冷阀,进行压缩机降低排气温度的热力学特性试验,解决替代过程中压缩机排温过高,润滑恶化的困难,为工程实际应用创造了条件。2喷射液冷阀的结构及工作原理本试验是采用喷射液冷阀,进行其热力学特性试验。喷射液冷阀在结构上与热力膨胀阀很相… 相似文献
660.
本文实验研究了山东某矿煤矸石的岩石组成、矿物组成、化学组成、粒度、强度,煤矸石中Al2O3含量、热值与煤矸石粒度、强度的关系.对该矿煤矸石选择性破碎分选进行实验研究. 相似文献