Special Kinds of Processes

Adiabatic processes occur without any exchange of heat between the system and its surroundings. Isothermal processes occur at constant temperature, isobaric processes at constant pressure, isochoric at constant volume, and isoplethal at constant composition. Finally, in a cyclical process, initial and final states of the system are identical. Integration in cyclical processes is often symbolized by the integral 

Scientists have special vocabulary terms to describe processes that take place under prescribed sets of conditions. Some of these terms are the following  

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In two-factor theory, hungers and other appetites must be elicited by stimuli that are outside of the person s control. If the theory s other assumptions were true, this tenet would be both possible and necessary. It would be possible because two-factor theory holds appetites to be special kinds of processes that initially depend on innate releasing stimuli but that can come to be elicited by arbitrary cues through pairing alone. It would be necessary in the case of aversive appetites, because, with conventional exponential discounting, there is no other mechanism to make a person generate them. The easiest cure for fear... 

Some authors have regarded prototropic reactions as special kinds of process, X being a hydrogen atom. However, hydrogen is not lost as the free ion H and indeed such reactions occur only in the presence of a base that can combine with the proton. The course of the reaction depends critically on the nature of the base. It is therefore better to reserve the designation S l for reactions where the group X is expelled as a neutral molecule [from an initial anion (RX)"] or as a stable cation X. ... 

Simulators are a special kind of expert systems and should be treated as such. They should be used to support the decision making process but not to replace the human creativity. 

The percolation processes were first developed by Flory [235] and Stockmayer [236] to describe polymerization process, which result in gelation, that is, the formation of very large networks of molecules connected by chemical bonds. But, their theory was developed only for a special kind of network, namely, the Bethe lattice, an infinite branching structure without any closed loops. Broadbent and Hammersley have developed a more general theory and have introduced it into the... 

A special class of reservoir capacity known as extraction was introduced in Chapter 4. Thermodynamically, the process is no different from the features described above, but from a use point of view, the process represents a special kind of bottle. Instead of leakage via diffusion caused by a potential energy difference, the leak arises from a shift in the partition coefficient from a change in temperature or in the solvent environment. 

Internal process Transport or transformation process which affects one or several state variables. An output flux is a special kind of internal process Example Biodegradation of chemical i in a lake... 

We have introduced the Fokker-Planck equation as a special kind of M-equation. Its main use, however, is as an approximate description for any Markov process Y(t) whose individual jumps are small. In this sense the linear Fokker-Planck equation was used by Rayleigh 0, Einstein, Smoluchowskin), and Fokker, for special cases. Subsequently Planck formulated the general nonlinear Fokker-Planck equation from an arbitrary M-equation assuming only that the jumps are small. Finally Kolmogorov8 provided a mathematical derivation by going to the limit of infinitely small jumps. 

Hence, by introducing the special four kinds of processes, the term To Sirr in Eq. (15) is found to be equal to T0EAS . 

For free radicals which are not involved in termination processes, i.e. those radicals which are the most reactive and, accordingly, the least concentrated, the QSSA can be applied even during the true induction period of the reaction. This is so for chain carrier radicals not involved in termination processes the concentrations of these radicals are not at all constant or slowly varying during the induction period however, the QSSA may be applied to them. For this reason, this special kind of QSSA will be termed pseudo-stationary state approximation (PSSA). As a consequence of the PSSA, the observation of a non-quasi-stationary behaviour for a radical concentration does not necessarily mean that the QSSA cannot be applied. This fact has probably played a role in the criticism of the QSSA. 

This equation, combining the first and second laws, is derived for the special case of a reversible process. However, it contains only properties of the system. Properties depend on state alone, and not on the kind of process that produces the state. Therefore, Eq. (6.1) is not restricted in application to reversible processes. However, the restrictions placed on the nature of the system cannot be relaxed. Thus Eq. (6.1) applies to any process in a system of constant mass that results in a differential change from one equilibrium state to another. The system may consist of a single phase (a homogeneous system), or it may be made up of several phases (a heterogeneous system) it may be chemically inert, or it may undergo chemical reaction. The only requirements are that the system be closed and that the change occur between equilibrium states. 

The development of thermodynamics is facilitated by the introduction of a special kind of nonflow process characterized as reversible. A process is reversible when its direction can be reversed at any point by an infinitesimal change in external conditions. 

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