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Subsystems independent

Internally equilibrated subsystems, which act as free energy reservoirs, are already as random as possible given their boundary conditions, even if they are not in equilibrium with one another because of some bottleneck. Tlius, the only kinds of perturbation that can arise and be stabilized when they are coupled are those that make the joint system less constrained than the subsystems originally were. (This is Boltzmann s H-theorem [9] only a less constrained joint system has a liigher maximal entropy than die sum of entropies from the subsystems independently and can stably adopt a different form.) The flows that relax reservoir constraints are thermochemical relaxation processes toward the equilibrium state for tlte joint ensemble. The processes by wliich such equilibration takes place are by assumption not reachable within the equilibrium distribution of either subsystem. As the nature of the relaxation phenomenon often depends on aspects of the crosssystem coupling that are much more specific than the constraints that define either reservoir, they are often correspondingly more complex than the typical processes... [Pg.396]

An important property of the stockholder molecular fragments is manifested by their equalization of the local values of a given measure of the entropy deficiency density at the corresponding global value, for the system as a whole [30,33]. An example of such locally equalized information quantities are the subsystem-independent local enhancement factors of the Hirshfeld subsystem densities (equation (91a)) ... [Pg.165]

Resource sharing system provides the connection open data, avoid coal mine power network subsystems independent operation monitoring island formation. [Pg.489]

It is still necessary to consider the role of entropy m irreversible changes. To do this we return to the system considered earlier in section A2.1.4.2. the one composed of two subsystems in themial contact, each coupled with the outside tliroiigh movable adiabatic walls. Earlier this system was described as a function of tliree independent variables, F , and 0 (or 7). Now, instead of the temperature, the entropy S = +. S P will be... [Pg.336]

In some cases, e.g., the Hg/NaF q interface, Q is charge dependent but concentration independent. Then it is said that there is no specific ionic adsorption. In order to interpret the charge dependence of Q a standard explanation consists in assuming that Q is related to the existence of a solvent monolayer in contact with the wall [16]. From a theoretical point of view this monolayer is postulated as a subsystem coupled with the metal and the solution via electrostatic and non-electrostatic interactions. The specific shape of Q versus a results from the competition between these interactions and the interactions between solvent molecules in the mono-layer. This description of the electrical double layer has been revisited by... [Pg.804]

If equation (2.51) is the total differential for as a function of two variables, 1 and 2, we can expect that its partial derivatives (d E/d Zi) and (<9 /c> 2)5 can be expressed as functions of only those two variables. That is, — ( , 2). Thus, derivatives of (<9 /<9 ) and (d E/d Zi)- with respect to variables other than 1 and 2 should be zero. As we consider the implications of this statement, it is important to note that a change can be made independently in the r variable of one subsystem without affecting that of the other, but a change in 0 will affect both subsystems (since 0 is the same in both subsystems). Therefore, we must consider the implications for c and 0 separately in the analysis that follows. [Pg.74]

The first derivative on the right-hand side of equation (2.53) must be zero because subsystems 1 and 2 have been defined to be independent of each other. Therefore, (50/5 ) in the second term of equation (2.53) must also equal zero in order for this equation to be true for all conditions. In a similar manner, starting with the equivalent equations involving the derivative of 0 /0, one can show that (50/5zi) = 0. If one substitutes this last result into equation (2.52), one gets (50 /5zi) = 0, and the conclusion that 0 is independent of ri. From a similar treatment, one can also show that (5 2/5c2) = 0, so that 02 is independent of r2. Thus, since the two ratios i/0 and 2/0 are independent of r neither 0, 0i, nor 0 can depend upon the c variables. [Pg.75]

The Gibbs energy of an electroneutral system is independent of the electrostatic potential. In fact, when substituting into Eq. (3.7) the electrochemical potentials of the ions contained in the system and allowing for the electroneutrality condition, we can readily see that the sum of aU terms jZjF f is zero. The same is true for any electroneutral subsystem consisting of the two sorts of ion and (particularly when these are produced by dissociation of a molecule of the original compound k into x+ cations and x anions), for which... [Pg.38]

The reason for adding this second term is to show that the integrand is short-ranged and hence that the integral is independent of x. Since the most likely subsystem force equals that imposed by the reservoir, Xs Xr, with relatively negligible error, the asymptote can be written... [Pg.42]

The first term on the right-hand side is independent of the subsystem and may be neglected. With this, the entropy of the total system constrained to be in the macrostate Es is the sum of that of the isolated subsystem in that macrostate and that of the reservoirs,... [Pg.59]

It is important to note that in this method, the dynamic fluctuations associated with the QM subsystem are assumed to be independent of the fluctuations from the MM subsystem. Also, in this method we assume that the contributions of the fluctuations of the QM subsystem to the total free energy are the same along the reaction coordinate. We have recently addressed these approximations by developing a novel reaction path potential method where the dynamics of the system are sampled by employing an analytical expression of the combined QM/MM PES along the MEP [40],... [Pg.65]

In this case, A is independent of the frequency characteristics of the nuclear subsystems. [Pg.161]

In this approach accident cases and design recommendations can be analysed level by level. In the database the knowledge of known processes is divided into categories of process, subprocess, system, subsystem, equipment and detail (Fig. 6). Process is an independent processing unit (e.g. hydrogenation unit). Subprocess is an independent part of a process such as reactor or separation section. System is an independent part of a subprocess such as a distillation column with its all auxiliary systems. Subsystem is a functional part of a system such as a reactor heat recovery system or a column overhead system including their control systems. Equipment is an unit operation or an unit process such as a heat exchanger, a reactor or a distillation column. Detail is an item in a pipe or a piece of equipment (e.g. a tray in a column, a control valve in a pipe). [Pg.89]

This makes it clear that we regard our System as spanning the entire business there is one per VideoBusiness. It will probably be designed as a distributed system of independent subsystems in each store but that apsect will be captured separately. [Pg.644]

In order to understand why a system of equations that includes a subsystem of equations with fewer variables than equations is not determinate, consider the following cases Case A—the subsystem of equations contains an equation that is not independent for the remaining equations in the subsystems Case B—the variables for the subsystem are overspecified, that is, in the subsystem there are more equations than variables. At the same time, in the remaining equations, there are more variables than equations. Case B occurs because a variable was treated as a parameter (constant) in the equations in which it appears, and a parameter was treated as a variable in the equations in which it appears. In Case A, the system equations are not consistent and no solution to the process model exists. In Case B, a solution cannot be obtained either. [Pg.198]

It must partition the system into the smallest possible subsystems that can be solved independently in sequence. [Pg.199]

In formulating a model of a very large process such as a whole chemical plant, the possibility exists that a subset of the system equations does not contain any variables in common with the remaining equations in the system. Such a subset of equations may physically correspond to a process unit or group of process units that are not connected in any way to the remaining units in the process. If this situation occurs, the subset of equations, which is called a disjoint subsystem, can be solved completely independently of the remaining equations in the system. Identification of these disjoint subsystems reduces the dimensionality of the complete system to that of the largest disjoint subsystem. [Pg.209]

For systems consisting of M independent subsystems (such as adsorbent molecules), we can write ... [Pg.313]

This form of Dp implies that Ap = 0 for each p > 1, a reflection of the fact that an independent-electron wavefunction consists of one-electron subsystems coupled only by exchange. [Pg.273]

To make a quantitative treatment, we define a system including a tip and a sample, as shown in Fig. 7.6. Independent electron approximation is applied. The Schrbdinger equation is identical to Eq. (7.6), with the potential surface shown in Fig. 7.6. Similar to the treatment of hydrogen molecular ion, a separation surface is drawn between the tip and the sample. The exact position of the surface is not important. Define two subsystems, the sample S and the tip T, with potential surfaces Hs and Ut, respectively, as shown in Fig. 7.6 (c) and... [Pg.186]

There are special cases where the direct mechanisms are linearly independent and constitute a basis. If all the direct mechanisms for a particular reaction r are disjoint, in the sense of containing no steps in common, then they are obviously linearly independent, or if there is only one direct mechanism for r, it is independent. This last case suggests a way of finding all the direct mechanisms in a chemical system. If we can find a subsystem which contains at most one mechanism m for any reaction r, then m is direct. In other words, m is a direct mechanism if S — Q in the chemical system, consisting just of the steps in m. [Pg.282]

In a chemical system with S steps and a maximum of Q linearly independent elementary reactions every set of Q steps whose reactions are linearly independent constitutes a cycle-free subsystem. It is apparent that, if R(Sj),..., R(sq) are linearly independent, then no cycle can be formed with the steps... [Pg.287]


See other pages where Subsystems independent is mentioned: [Pg.133]    [Pg.133]    [Pg.760]    [Pg.264]    [Pg.96]    [Pg.776]    [Pg.126]    [Pg.272]    [Pg.203]    [Pg.73]    [Pg.484]    [Pg.125]    [Pg.37]    [Pg.44]    [Pg.162]    [Pg.66]    [Pg.329]    [Pg.186]    [Pg.199]    [Pg.66]    [Pg.320]    [Pg.34]    [Pg.34]    [Pg.196]    [Pg.187]    [Pg.287]    [Pg.287]    [Pg.387]    [Pg.177]    [Pg.37]   
See also in sourсe #XX -- [ Pg.3 , Pg.3 , Pg.3 , Pg.5 , Pg.6 , Pg.20 ]




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