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Systems far from equilibrium

All the deseribed results [64-66] pointed out that the standard dynamie seahng formalism developed for the deseription of rough interfaees [60] is suitable for the rationalization of the interfaee behavior in reaetive systems far from equilibrium sueh as the ZGB model. However, mueh work remains to be done in order to elarify the role of high surfaee mobility of A speeies in the behavior of the reaetion interfaees. [Pg.404]

Procaccia, I. Ross, J. (1978). Stability and relative stability in reactive systems far from equilibrium. II. Kinetic analysis of relative stability of multiple stationary states. J. Chem. Phys., 67, 5565-71. [Pg.534]

Equilibrium thermodynamics is usually interpreted in terms of 3-spatial energy symmetry anyway, to begin with, and then one loses some control steadily and hence loses some ordering. Actually, the thermodynamics of systems far from equilibrium in 3-spatial energy flow, must always be in symmetry in energy 4-flow 3-space disequilibrium thermodynamics and 4-space equilibrium thermodynamics are postulated as different views of the same thing. [Pg.661]

Particularly during its excitation discharge, the system must be an open thermodynamic system far from equilibrium in its energetic exchange with the active vacuum. In that case classical equilibrium thermodynamics does not apply, and such a system is permitted to... [Pg.670]

M. Open System far from Equilibrium, Multiple Subprocesses, and Curved Spacetime... [Pg.700]

The open system far from equilibrium process of this invention thus allows electromagnetic power systems to be developed that permissibly exhibit a coefficient of performance (COP) of COP> 1.0. It allows electromagnetic power systems to be developed that permissibly (a) power themselves and their loads and losses, (b) self-oscillate, and (c) exhibit negentropy. [Pg.742]

One particular pattern of behaviour which can be shown by systems far from equilibrium and with which we will be much concerned is that of oscillations. Some preliminary comments about the thermodynamics of oscillatory processes can be made and are particularly important. In closed systems, the only concentrations which vary in an oscillatory way are those of the intermediates there is generally a monotonic decrease in reactant concentrations and a monotonic, but not necessarily smooth, increase in those of the products. The free energy even of oscillatory systems decreases continuously during the course of the reaction AG does not oscillate. Nor are there specific individual reactions which proceed forwards at some stages and backwards at others in fact our simplest models will comprise reactions in which the reverse reactions are neglected completely. [Pg.2]

The thermodynamics of systems far from equilibrium are discussed in a number of texts, such as... [Pg.30]

Self-organization manifests itself only in systems far from equilibrium and consisting of a large number of objects, whose cooperative behaviour is sometimes considered in terms of the non-equilibrium critical phenomena... [Pg.618]

In 1977. Professor Ilya Prigogine of the Free University of Brussels. Belgium, was awarded Ihe Nobel Prize in chemistry for his central role in the advances made in irreversible thermodynamics over the last ihrec decades. Prigogine and his associates investigated Ihe properties of systems far from equilibrium where a variety of phenomena exist that are not possible near or al equilibrium. These include chemical systems with multiple stationary states, chemical hysteresis, nucleation processes which give rise to transitions between multiple stationary states, oscillatory systems, the formation of stable and oscillatory macroscopic spatial structures, chemical waves, and Lhe critical behavior of fluctuations. As pointed out by I. Procaccia and J. Ross (Science. 198, 716—717, 1977). the central question concerns Ihe conditions of instability of the thermodynamic branch. The theory of stability of ordinary differential equations is well established. The problem that confronted Prigogine and his collaborators was to develop a thermodynamic theory of stability that spans the whole range of equilibrium and nonequilibrium phenomena. [Pg.349]

King, G. A. M., 1983, Reactions for chemical systems far from equilibrium. J. Chem. Soc. Faraday Tram. 1 79,75-80. [Pg.188]

Self-replication and mutagenicity in an open system far from equilibrium are thus sufficient to produce behavior patterns including selection and evolution. Even in relatively simple replication systems properties optimal with respect to the wild-type can be produced in vitro in a few generations. Such effects must be the consequence of a physical principle. Can such a principle be formulated quantitatively ... [Pg.128]

G. Nicolis, in Systems far from equilibrium, Lecture Notes in Physics, Vol. 132, Springer-Verlag, Berlin, 1980,... [Pg.197]

Note that the appearance of a generic time scale is a characteristic property of a dissipative system and T generates its time evolution in scaled time units. Such time operators are strictly speaking forbidden in standard Quantum Mechanics, see Ref. [24] for further aspects on the problem, however, in open systems far from equilibrium they do not only exist but might also be useful in many applications, see below and [4-10, 13-15], The form (15) has been investigated and obtained... [Pg.126]

The volume or space in which reaction occurs is called the reactor. Closed systems, for which matter is neither gained nor lost, are referred to in the engineering literature as batch reactors. An open, or flow reactor, which permits the flow of matter in and out of the system, allows for the continuous and convenient change of solution composition. Most importantly, the continuous flow of matter into and out of the flow reactor trivially solves the problem of maintaining the system far from equilibrium, while facilitating the detection and determination of the chemical properties of species in these states. [Pg.8]

Prior to the simulation at finite temperature, the system must be heated up to the target temperature and thermally equilibrated. The temperature should be distributed among all the normal modes in the system. Thermal equilibration usually requires running dynamics for a long period of time (of the order of picoseconds). This time may be shortened if the warm-up procedure does not displace the system far from equilibrium. Thus, the warm-up may be realized by a sequence of kinetic energy pulses, followed by a short relaxation (free dynamics). If these pulses are orthogonal, then different normal mode become excited. It should be emphasized also at this point, that prior to the constrained dynamics simulation, the warm-up and equilibration should be performed with the same constraints that will be used in the sampling simulation. [Pg.233]

H. Qian andD. A. Beard. Thermodynamics of stoichiometric biochemical networks in living systems far from equilibrium. Biophys. Chem., 114 213-220, 2005. [Pg.303]

Example 4.8 Chemical reactions and reacting flows The extension of the theory of linear nonequilibrium thermodynamics to nonlinear systems can describe systems far from equilibrium, such as open chemical reactions. Some chemical reactions may include multiple stationary states, periodic and nonperiodic oscillations, chemical waves, and spatial patterns. The determination of entropy of stationary states in a continuously stirred tank reactor may provide insight into the thermodynamics of open nonlinear systems and the optimum operating conditions of multiphase combustion. These conditions may be achieved by minimizing entropy production and the lost available work, which may lead to the maximum net energy output per unit mass of the flow at the reactor exit. [Pg.174]

For systems not far from equilibrium, the total entropy production reaches a minimum value and also assures the stability of the stationary state. However, for systems far from equilibrium, there is no such general criterion. Far from equilibrium, we may have order in time and space, such as, appearance of rhythms, oscillations, and morphological structurization. [Pg.609]

Example 12.5 Macroscopic behavior in systems far from equilibrium Consider the nonequilibrium chemical system... [Pg.613]

When a system is sufficiently far from equilibrium, it may arrive at a bifurcation of states and move to ordered structures. Transitions between different modes of dynamic organizations are called bifurcation. If the system continues to move away from equilibrium, the structures become more complex, leading to a chaotic situation in the macroscopic sense. Some regularity may involve in such chaotic behavior. To study the behavior of systems far from equilibrium, a new interdisciplinary field called synergetics was developed. Synergetics is concerned with the cooperation of individual parts of the system that produce macroscopic spatial and temporal structures, which are mainly dissipative. [Pg.632]

In general, for systems far from equilibrium it is not at all clear how one should approximate the full xc potential r jc[n](r, t). The most general possible nonlinear dependence of t>xc[n](> . 0 on n must involve at least terms with n evaluated at one space-time point = (r, t ), terms with n evaluated at two spacetime points and terms with n evaluated at three points and... [Pg.127]


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