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排序方式: 共有139条查询结果,搜索用时 15 毫秒
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I.IntroductionItilasbeenl'oundthatthewavelettheoryisapowerfLllmathematicaltooldevelopedillrecentyears.Asanewmathematicaltool,ithasbeenextensivelyappliedintheanalysisofsignalprocess,parttenrecognition,functionapproximation,andsolvingdifferentialequation(s),etc..Sinceasmallsignalinasighalprocesscanbecapturedbythewavelettheory,itsapplicationshavebeenpaidmuchattentionbothintheoryandinengneeringf'~'].Recently,thewavelettheory11asbeengeneralizedtofindanumericalsolutionofadifferentialequation.Forex… 相似文献
26.
Vincenzo de Filippis 《数学学报(英文版)》2009,25(12):1965-1974
Let R be a prime ring, L a non-central Lie ideal of R and g a non-zero generalized derivation of R. If g acts as a Jordan homomorphism on L, then either g(x) = x for all x ∈ R, or char(R) = 2, R satisfies the standard identity s4(x1, x2, x3, x4), L is commutative and u2 ∈ Z(R), for any u C L. We also examine some consequences of this result related to generalized derivations which act as Jordan homomorphisms on the set [I, I], where I is a non-zero right ideal of R. 相似文献
27.
Christopher G. Jesudason 《Journal of mathematical chemistry》2006,39(1):201-230
Chemical and other reaction theories involving thermodynamical equilibrium states utilize statistical mechanical equilibrium
density distributions. Here, a definition of heat-work transformation termed thermo-mechanical coherence is first made, and
it is conjectured that most molecular bonds have the above heat-work transformation property, which models a chemical bond
as a “centrifugal heat engine”, where the internal energy state need not correspond to any of the standard equilibrium densities.
Expressions are derived for the standard Gibbs free energy, enthalpy, and entropy where the bond coordinates need not conform
to a non-degenerate Boltzmann state, since bond breakdown and formation are processes that have direction, whereas equilibrium
distributions are derived when the Hamiltonian is of fixed form, which is not the case for chemical reactions using localized
Hamiltonians. The empirically determined Gibbs free energy from a known molecular dynamics simulation of a dimer reaction
, accords rather well with the theoretical estimate. A relation connecting the rate of reaction with the equilibrium constant
and other kinetic parameters is derived and could place the commonly observed linear relationship between the logarithms of
the rate constant and equilibrium constant on a firmer theoretical footing. These relationships could include analogues of
the Hammett correlations used extensively in physical organic chemistry, as well as others which are temperature dependent.
One prediction of the principles developed here is that the equilibrium standard reaction free energy is more dependent on
the height of the intermolecular potential than its depth, so that the sign of the ΔG
θ can change for varying barrier height with fixed well depth, which may appear counter-intuitive. All the above developments
can be tested directly in simulations and therefore provides a fertile ground for further research with significant implications
on how standard states are determined in relation to the direction of chemical reaction.This work treats the molecular bond
using standard thermodynamics as if it were a system, and it is anticipated that with the advent of single-molecule science
and experiment, that might be one direction in which molecular statistical thermodynamics would develop. 相似文献
28.
Let L be a J-subspace lattice on a Banach space X and Alg L the associated J-subspace lattice algebra. Let A be a standard operator subalgebra (i.e., it contains all finite rank operators in AlgL) of AlgL and M■B(X) the Alg L-bimodule. It is shown that every linear Jordan triple derivation from A into M is a derivation, and that every generalized Jordan (triple) derivation from A into M is a generalized derivation. 相似文献
29.
In this paper,we give the notion of derivations of Lie 2-algebras using explicit formulas,and construct the associated derivation Lie 3-algebra.We prove that isomorphism classes of non-abelian extensions of Lie 2-algebras are classified by equivalence classes of morphisms from a Lie 2-algebra to a derivation Lie 3-algebra. 相似文献
30.
S. M. Bhatwadekar Amartya K. Dutta 《Transactions of the American Mathematical Society》1997,349(8):3303-3319
In this paper we study the kernel of a non-zero locally nilpotent -derivation of the polynomial ring over a noetherian integral domain containing a field of characteristic zero. We show that if is normal then the kernel has a graded -algebra structure isomorphic to the symbolic Rees algebra of an unmixed ideal of height one in , and, conversely, the symbolic Rees algebra of any unmixed height one ideal in can be embedded in as the kernel of a locally nilpotent -derivation of . We also give a necessary and sufficient criterion for the kernel to be a polynomial ring in general.