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Partition discrete

Let us now turn to the case T -> 0. First of all, somewhat suspicious is the combination of the continuous integral (2.1) with the discrete partition function Zq (2.13), usual for CLTST. This serious deficiency cannot be circumvented in the framework of this CLTST-based formalism, and a more rigorous reasoning is needed to describe the quantum situation. Introduction of adequate methods will be the objective of the next sections devoted to the path-integral formalism, so here we... [Pg.14]

By using steps 1 and 2, a discrete partition is often obtained, particularly for molecular graphs. [Pg.207]

The two-member class is chosen, and atom 10 is preliminarily marked on backtrack level 1 (btll). Atom 14 becomes unique as a result, and refinement by 10 and then 14 leads to a discrete partition, candidate 1 ( 1) for canonical numbering. Backtracking and alternative marking of 14 followed by refinement results in another discrete partition ( 2) which leads to the same matrix of bond multiplicities as the first (an automorphism, the symmetry of the phenyl residue, marked by a in Table 5.4). Therefore the first candidate is kept and used for assigning canonical numbers, as shown. [Pg.210]

Here matrix element (4, 2) 0 (in italics) determines that all discrete partitions to be derived from this partial numbering will be worse than candidate 2. [Pg.213]

Centrifugal partition chromatography (CPC), a type of CCC that uses discrete partition cells inside a rotor, was used by Renault et al. (1997) to separate anthocyanins from black currant and grape skins. They used two instmments from Sanki Engineering Ltd (Kyoto, Japan) a laboratory model LLB-M and a pilot-scale model LLI-7, both fitted with a stacked disks type rotor. [Pg.258]

This is better understood with a picture see figure B3.3.11. The discretized path-integral is isomorphic to the classical partition fiinction of a system of ring polymers each having P atoms. Each atom in a given ring corresponds to a different imaginary tune point p =. . . P. represents tire interatomic interactions... [Pg.2274]

In their original theoretical model of chromatography, Martin and Synge treated the chromatographic column as though it consists of discrete sections at which partitioning of the solute between the stationary and mobile phases occurs. They called each section a theoretical plate and defined column efficiency in terms of the number of theoretical plates, N, or the height of a theoretical plate, H where... [Pg.553]

Eukaryotic ceils possess a discrete, membrane-bounded nucleus, the repository of the cell s genetic material, which is distributed among a few or many chromosomes. During ceil division, equivalent copies of this genetic material must be passed to both daughter ceils through duplication and orderly partitioning of the chromosomes by the process known as mitosis. Like prokaryotic... [Pg.26]

The time evolution of the function f is thus replaced by a sequence of discrete symbols labeling the bins visited by each point of the orbit. Because of the coarse-graining of the phase space, however, detailed knowledge of the actual orbits is generally lost i.e. many different orbits may yield the same symbolic sequence. Different state-space partitionings also generally give rise to different symbolic representations. [Pg.196]

Emulsion polymerization has proved more difficult. N " Many of the issues discussed under NMP (Section 9.3.6.6) also apply to ATRP in emulsion. The system is made more complex by both activation and deactivation steps being bimolecular. There is both an activator (Mtn) and a deactivator (ML 1) that may partition into the aqueous phase, although the deactivator is generally more water-soluble than the activator because of its higher oxidation state. Like NMP, successful emulsion ATRP requires conditions where there is no discrete monomer droplet phase and a mechanism to remove excess deactivator built up in the particle phase as a consequence of the persistent radical effect.210 214 Reverse ATRP (Section 9.4,1,2) with water soluble dialky 1 diazcncs is the preferred initiation method/87,28 ... [Pg.498]

Fig. 19. Partitioning of representation space into regions of discrete pattern class using linear discriminants. Fig. 19. Partitioning of representation space into regions of discrete pattern class using linear discriminants.
Here va and va are the stoichiometric coefficients for the reaction. The formulation is easily extended to treat a set of coupled chemical reactions. Reactive MPC dynamics again consists of free streaming and collisions, which take place at discrete times x. We partition the system into cells in order to carry out the reactive multiparticle collisions. The partition of the multicomponent system into collision cells is shown schematically in Fig. 7. In each cell, independently of the other cells, reactive and nonreactive collisions occur at times x. The nonreactive collisions can be carried out as described earlier for multi-component systems. The reactive collisions occur by birth-death stochastic rules. Such rules can be constructed to conserve mass, momentum, and energy. This is especially useful for coupling reactions to fluid flow. The reactive collision model can also be applied to far-from-equilibrium situations, where certain species are held fixed by constraints. In this case conservation laws... [Pg.109]

Johnson and Swindell [77] developed a method for evaluating the complete particle distribution and its effect on dissolution. This method divided the distribution into discrete, noncontinuous partitions, from which Johnson and Swindell determined the dissolution of each partition under sink conditions. The dissolution results from each partition value were then summed to give the total dissolution. Oh et al. [82] and Crison and Amidon [83] performed similar calculations using an expression for non-sink conditions based on a macroscopic mass balance model for predicting oral absorption. The dissolution results from this approach could then be tied to the mass balance of the solution phase to predict oral absorption. [Pg.154]

In the so-called primitive representation of the discretized path-integral approach [141], the canonical partition function for finite P has the form... [Pg.310]

Crystals lack some of the dynamic complexity of solutions, but are still a challenging subject for theoretical modeling. Long-range order and forces in crystals cause their spectrum of vibrational frequencies to appear more like a continuum than a series of discrete modes. Reduced partition function ratios for a continuous vibrational spectrum can be calculated using an integral, rather than the hnite product used in Equation (3) (Kieffer 1982),... [Pg.76]

The adsorbent used in the Sorbex process is partitioned into discrete beds within the Sorbex chambers. These beds are then allocated among four main Sorbex zones. Table 8.2 lists these zones and their corresponding function. [Pg.256]

It should be emphasised that the dependence on partition coefficient occurs only in the earliest stages of the transfer which is unlikely to apply to the cases examined in structure/ activity studies. It should be noted also that if the constant supply concentration in the model is replaced by a discrete dose application the availance within the organism would also depend on partition coefficient, but would pass through a minimum with changing P rather than a maximum. [Pg.191]

In contrast to partitioning methods that involve dimension reduction of chemical reference spaces, MP is best understood as a direct space method. However, -dimensional descriptor space is simplified here by transforming property descriptors with continuous or discrete value ranges into a binary classification scheme. Essentially, this binary space transformation assigns less complex -dimensional vectors to test molecules, with each dimension having unity length of either 0 or 1. Thus, although MP analysis proceeds in -dimensional descriptor space, its dimensions are scaled and its complexity is reduced. [Pg.295]

The electrostatic properties of the molecule may be used as a criterion for judging the MEM enhancement. Using the uniform prior density, the MEM molecular dipole moment derived by the discrete boundary partitioning of space (chapter 6) is only 1.3 D, compared with 9.1 D based on the experimental density,... [Pg.120]


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See also in sourсe #XX -- [ Pg.207 ]




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