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991.
Abstract In this study, it is demonstrated that the Coulomb interactions explains the essential of experimental thermodynamic and transport thermodynamic results. 相似文献
992.
Adela Novac 《Numerical Functional Analysis & Optimization》2013,34(7):930-941
In this article, an abstract theory regarding variational properties of the fixed points of contractions and Perov contractions is applied to boundary value problems on semi-line for second-order differential equations and systems. The main result states that under suitable conditions the unique solution of such a system is a Nash-type equilibrium of the corresponding energy functionals. 相似文献
993.
Robert Luxenhofer Stephan Huber Julia Hytry Jing Tong Alexander V. Kabanov Rainer Jordan 《Journal of polymer science. Part A, Polymer chemistry》2013,51(3):732-738
We describe the synthesis and characterization of the first water‐soluble and chiral poly(2,4‐disubstituted‐2‐oxazoline)s. While poly(2,4‐dimethyl‐2‐oxazoline)s are water soluble up to 100 °C, aqueous solutions of poly(2‐ethyl‐4‐methly‐2‐oxazoline) exhibit a lower critical solution temperature. This is discussed in context with its constitutional isomers poly(2‐oxazoline)s and poly(2‐oxazine)s. Circular dichroism spectroscopy revealed strong Cotton effects, which are also responsive to temperature in aqueous solution. It is therefore hypothesized that structures, comparable to polyproline helices, are formed in aqueous solution. In contrast to polyproline, poly(2,4‐disubstituted‐2‐oxazoline)s are highly water soluble and therefore represent very interesting pseudo‐polypeptides that may be useful to develop responsive biomimetic biomaterials. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
994.
Polyakov V. A. Shlitsa R. P. Khitrov V. V. Zhigun V. I. 《Mechanics of Composite Materials》2001,37(2):91-106
The distribution of transverse stresses in the midlayer of a composite sandwich panel under multipoint loading is investigated. The stresses averaged across the thickness of a soft filler are estimated using a discrete model. Finite expressions for the compression of the filler along the length of the panel are derived by means of superposition of the local effects from the bending of face layers under an infinite system of transverse point forces constant across the panel thickness. The effects of compression and transverse extension of the filler, in the case of a high distribution frequency of these forces, i.e., when the distance between the forces is comparable to the panel thickness, are revealed. Compression of the panel by two systems of forces applied symmetrically or nonsymmetrically to the upper and lower faces is considered. The bending characteristics in the cases of loading with point forces and piecewise distributed loads are compared. The formulas obtained are used to determine the length of a small region on the panel surface for which the local effects from the distributed pressure and the point force are equivalent. The corresponding estimates are obtained in a closed form. The analysis, carried out with varied parameters of the structure, allows us to elucidate the peculiarities of the effect of discontinuous loads on the design characteristics in the local zones, using finite expressions derived by the operational method. 相似文献
995.
Renato Assunção Peter Guttorp 《Annals of the Institute of Statistical Mathematics》1999,51(4):657-678
We consider robustness for estimation of parametric inhomogeneous Poisson point processes. We propose an influence functional to measure the effect of contamination on estimates. We also propose an M-estimator as an alternative to maximum likelihood estimator, show its consistency and asymptotic normality. 相似文献
996.
This paper deals with the existence and multiplicity problem of the equilibrium solutions of an elastic spherical cap within
nonlinear strain theory. We pose the problem in the form of a three parameter bifurcation problem, one parameter being related
to the load, the others to the geometry. When the geometrical parameters are different from zero, the so-called generic case,
we revisit the nonuniqueness results, and explore the solutions in the parameter space. Then we analyze the formal limits
as the geometrical parameters tend to zero. When the curvature tends to zero, we obtain from the nonlinear shell a von Kármán
plate, a new, although natural, result. When the thickness parameter tends to zero, we get a nonlinear membrane problem. A
study of the latter gives infinitely many solutions, and we discuss the construction, shapes, and stability in detail.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
997.
1NumberandDistributionofCriticalPoilltsConsiderthefollowingcubicsystem:itcontainsonlytwocubictermspx'andqx'morethanthegeneralquadraticsystem:Thecoordinatesofthecriticalpointsatinfinityof(1)mustsatisfytheequation:px'y~qx'=0.(3)SoA(P,q,0)andB(0,l,0)aretheonlycriticalpointsatinfinityof(1).Itiseasilyseenthatthetwocharacteristicrootsof(1)atAareAl=AZ=--p,soAisastable(unstable)nodewhenp>0(<0).Moreover,Bisahigherordercriticalpointatinfinityof(1)withindex0,itisthepileupof3criticalpointsontheequat… 相似文献
998.
S. I. Pechenyuk 《Russian Chemical Bulletin》1999,48(6):1017-1023
The modern theoretical views on the point of zero charge of the oxide hydroxide surface are considered. Methods for determination
of the pH of the point of zero charge and the use of this value to characterize the properties of oxide hydroxides are described.
Examples of using the pH of the point of zero charge in studies of oxide anodes and amorphous oxide hydroxide sorbents are
presented.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1029–1035, June, 1999. 相似文献
999.
Stefan Langer 《国际流体数值方法杂志》2012,69(2):332-352
We derive and investigate point implicit Runge–Kutta methods to significantly improve the convergence rate to approximate steady‐state solutions of inviscid flows. It turns out that the point implicit Runge–Kutta can be interpreted as a preconditioned explicit Runge–Kutta method, where the preconditioner arises naturally as local derivative of the residual function. Moreover, many preconditioners suggested in the literature so far are identified as special case of our general ansatz. Conditions will be formulated such that explicit Runge–Kutta methods with local time stepping are equivalent to point implicit methods. In numerical examples, we will demonstrate the improved convergence rates. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
1000.
We point out that the quasiparticle spectrum of the Landau Fermi liquid theory has an extra Z2 symmetry, local in momentum space, which is not generic to the Hamiltonian with interactions. Thus the Fermi liquid is in this sense a (quantum) zero-temperature critical point. 相似文献