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51.
Cristian Rodrigo Muzzio Nicolás Gabriel Dini Adrián César Razzitte 《Physics and Chemistry of Liquids》2017,55(4):506-521
Highly concentrated electrolyte solutions were studied through a Monte Carlo-based simulator, developed to consider the water molecules not a homogeneous dielectric as usual, but as dipoles that can move and rotate within a 3D lattice. This approach allowed fast calculations of detailed interactions between the particles, which were described from mechanistic potentials including dipole–dipole, ion–dipole, ion–ion, and hydrogen bonding (HB) interactions. A good agreement was found between experimental data and simulated results. The study also provides new insights about the balance of the different interactions in systems with or without electrolytes, and the effects of the electrolytes addition on the original water structure. The proposed model was also compared with previous explicit models. 相似文献
52.
J. García-Melián C. Morales-Rodrigo J. D. Rossi A. Suárez 《Annali di Matematica Pura ed Applicata》2008,187(3):459-486
In this paper we perform an extensive study of the existence, uniqueness (or multiplicity) and stability of nonnegative solutions
to the semilinear elliptic equation − Δu = λ u − u
p
in Ω, with the nonlinear boundary condition ∂u/∂ν = u
r
on ∂Ω. Here Ω is a smooth bounded domain of with outward unit normal ν, λ is a real parameter and p, r > 0. We also give the precise behavior of solutions for large |λ| in the cases where they exist. The proofs are mainly
based on bifurcation techniques, sub-supersolutions and variational methods.
相似文献
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Manuel Delgado Cristian Morales-Rodrigo Antonio Suárez J. Ignacio Tello 《Nonlinear Analysis: Real World Applications》2010,11(5):3884-3902
This paper deals with a nonlinear system of parabolic–elliptic type with a logistic source term and coupled boundary conditions related to pattern formation. We prove the existence of a unique positive global in time classical solution. We also analyze the associated stationary problem. Moreover it is proved, under the assumption of sufficiently strong logistic damping, that there is only one nonzero homogeneous equilibrium, and all the solutions to the nonstationary problem tend to this steady state for large times. 相似文献
57.
Timed continuous Petri net (contPN) systems with infinite server semantics are nonlinear systems, particularly a subclass of piecewise linear (PWL) systems. This paper addresses several problems regarding the state observability of these systems. We assume that the initial marking/state is not known and by measuring the marking of some places we want to estimate all the others. First, a study of the different linear systems corresponding to a continuous Petri net system is performed. It is shown that in some cases, some of them are redundant, and so can be disregarded. The notion of distinguishable modes is introduced which helps us in giving a necessary and sufficient criterion for the observability in infinitesimal time. Structural observability, i.e., observability for all possible values of firing rates of transitions, is studied and it is proved that in some cases it can be reduced to a linear problem, even if the system is nonlinear. Using results from linear structured systems, the concept of weak structural or generic observability is considered. 相似文献
58.
Nicolás Andruskiewitsch Iván Angiono Agustín García Iglesias Akira Masuoka Cristian Vay 《Journal of Pure and Applied Algebra》2014
We develop a strategy to compute all liftings of a Nichols algebra over a finite dimensional cosemisimple Hopf algebra. We produce them as cocycle deformations of the bosonization of these two. In parallel, we study the shape of any such lifting. 相似文献
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Let ? be a convex function on a convex domain Ω⊂Rn, n?1. The corresponding linearized Monge–Ampère equation istrace(ΦD2u)=f, where is the matrix of cofactors of D2?. We establish interior Hölder estimates for derivatives of solutions to such equation when the function f on the right-hand side belongs to Lp(Ω) for some p>n. The function ? is assumed to be such that with ?=0 on ∂Ω and the Monge–Ampère measure is given by a density g∈C(Ω) which is bounded away from zero and infinity. 相似文献