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Nonequilibrium evolution

To describe an arbitrary nonequilibrium evolution of the adsorbate we need the whole hierarchy, or at least a suitably truncated subset. We can close the hierarchy at the level of 2-site correlators by a factorization of higher correlators with 1-site overlap [58,59]... [Pg.468]

Dynamic Density Functional Theory (DDFT), Fig. 1 Illustration of the local equilibrium approximation involved in the development of the DDFT. The left-hand side illustrates the nonequilibrium evolution of the density p(r t) thin lines) up to time t thick line). For the time evolution, the equal-time correlation function g(r, r t) is... [Pg.695]

One may then ask what applicable theory exists for the nonequilibrium evolution of a ufp aerosol system in the Brownian-particle approximation. One has still the restriction T t.. so that particle-particle collisions can be neglected. [Pg.23]

In the Brownian-particle approximation, therefore, one has an exact description of the nonequilibrium evolution of the aerosol system within the limitations imposed by restrictions (2.24-29). Such systems are partially described by (2.6) with... [Pg.24]

Mavri, J., Berendsen, H.J.C., Van Gunsteren, W.F. Influence of solvent on intramolecular proton transfer in hydrogen malonate. Molecular dynamics study of tunneling by density matrix evolution and nonequilibrium solvation. J. Phys. Chem. 97 (1993) 13469-13476. [Pg.34]

The present theory can be placed in some sort of perspective by dividing the nonequilibrium field into thermodynamics and statistical mechanics. As will become clearer later, the division between the two is fuzzy, but for the present purposes nonequilibrium thermodynamics will be considered that phenomenological theory that takes the existence of the transport coefficients and laws as axiomatic. Nonequilibrium statistical mechanics will be taken to be that field that deals with molecular-level (i.e., phase space) quantities such as probabilities and time correlation functions. The probability, fluctuations, and evolution of macrostates belong to the overlap of the two fields. [Pg.4]

Yamada and Kawasaki [68, 69] proposed a nonequilibrium probability distribution that is applicable to an adiabatic system. If the system were isolated from the thermal reservoir during its evolution, and if the system were Boltzmann distributed at t — x, then the probability distribution at time t would be... [Pg.51]

This shows that the nonequilibrium probability distribution is stationary during adiabatic evolution on the most likely points of phase space. [Pg.53]

The philosophical and conceptual ramifications of the nonequilibrium Second Law are very deep. Having established the credentials of the Law by the detailed analysis outlined earlier, it is worth considering some of these large-scale consequences. Whereas the equilibrium Second Law of Thermodynamics implies that order decreases over time, the nonequilibrium Second Law of Thermodynamics explains how it is possible that order can be induced and how it can increase over time. The question is of course of some relevance to the creation and evolution of life, society, and the environment. [Pg.83]

Microstate transitions, nonequilibrium statistical mechanics, 44—51 adiabatic evolution, 44—46 forward and reverse transitions, 47-51 stationary steady-steat probability, 47 stochastic transition, 46—47... [Pg.283]

Nonequilibrium statistical mechanics Green-Kubo theory, 43-44 microstate transitions, 44-51 adiabatic evolution, 44—46 forward and reverse transitions, 47-51 stationary steady-state probability, 47 stochastic transition, 464-7 steady-state probability distribution, 39—43 Nonequilibrium thermodynamics second law of basic principles, 2-3 future research issues, 81-84 heat flow ... [Pg.284]

By making use of classical or quantum-mechanical interferences, one can use light to control the temporal evolution of nuclear wavepackets in crystals. An appropriately timed sequence of femtosecond light pulses can selectively excite a vibrational mode. The ultimate goal of such optical control is to prepare an extremely nonequilibrium vibrational state in crystals and to drive it into a novel structural and electromagnetic phase. [Pg.55]

In their subsequent works, the authors treated directly the nonlinear equations of evolution (e.g., the equations of chemical kinetics). Even though these equations cannot be solved explicitly, some powerful mathematical methods can be used to determine the nature of their solutions (rather than their analytical form). In these equations, one can generally identify a certain parameter k, which measures the strength of the external constraints that prevent the system from reaching thermodynamic equilibrium. The system then tends to a nonequilibrium stationary state. Near equilibrium, the latter state is unique and close to the former its characteristics, plotted against k, lie on a continuous curve (the thermodynamic branch). It may happen, however, that on increasing k, one reaches a critical bifurcation value k, beyond which the appearance of the... [Pg.12]

The vision of irreversibility that appeared in this first group of works, which formed the object of the first monograph on nonequilibrium statistical mechanics by Prigogine (1962, LS.9), was the following. The necessary conditions for an irreversible evolution were ... [Pg.17]

TNC.15. I. Prigogine, Evolution Criteria, Variational principles and fluctuations, in Nonequilibrium Thermodynamics, Variational Techniques and Stability, University of Chicago, 1966, pp. 3-16. [Pg.46]

TNG.67.1. Prigogine, Nonequilibrium Thermodynamics and Chemical Evolution An Overview,... [Pg.49]

These new methods of nonequihbrium statistical mechanics can be applied to understand the fluctuating properties of out-of-equilibrium nanosystems. Today, nanosystems are studied not only for their structure but also for their functional properties. These properties are concerned by the time evolution of the nanosystems and are studied in nonequilibrium statistical mechanics. These properties range from the electronic and mechanical properties of single molecules to the kinetics of molecular motors. Because of their small size, nanosystems and their properties such as the currents are affected by the fluctuations which can be described by the new methods. [Pg.85]

The plan of this chapter is the following. Section II gives a summary of the phenomenology of irreversible processes and set up the stage for the results of nonequilibrium statistical mechanics to follow. In Section III, it is explained that time asymmetry is compatible with microreversibility. In Section IV, the concept of Pollicott-Ruelle resonance is presented and shown to break the time-reversal symmetry in the statistical description of the time evolution of nonequilibrium relaxation toward the state of thermodynamic equilibrium. This concept is applied in Section V to the construction of the hydrodynamic modes of diffusion at the microscopic level of description in the phase space of Newton s equations. This framework allows us to derive ab initio entropy production as shown in Section VI. In Section VII, the concept of Pollicott-Ruelle resonance is also used to obtain the different transport coefficients, as well as the rates of various kinetic processes in the framework of the escape-rate theory. The time asymmetry in the dynamical randomness of nonequilibrium systems and the fluctuation theorem for the currents are presented in Section VIII. Conclusions and perspectives in biology are discussed in Section IX. [Pg.85]

In this chapter, we review the current status of doping of SiC by ion implantation. Section 4.2 examines as-implanted depth profiles with respect to the influence of channeling, ion mass, ion energy, implantation temperature, fluence, flux, and SiC-polytype. Experiments and simulations are compared and the validity of different simulation codes is discussed. Section 4.3 deals with postimplant annealing and reviews different annealing concepts. The influence of diffusion (equilibrium and nonequilibrium) on dopant profiles is discussed, as well as a comprehensive review of defect evolution and electrical activation. Section 4.4 offers conclusions and discusses technology barriers and suggestions for future work. [Pg.114]


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Nonequilibrium

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