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Real auxiliary functions

Vitamin B6 enzyme models that can catalyze five types of reactions - transamination, racemization, decarboxylation, P-elimination and replacement, and aldolase-type reactions - have been reviewed. There are also five approaches to construct the vitamin B6 enzyme models (i) vitamin B6 augmented with basic or chiral auxiliary functional groups (ii) vitamin B6 having an artificial binding site (iii) vitamin B6-surfactant systems (iv) vitamin B6-polypeptide systems (v) polymeric and dendrimeric vitamin B6 systems. These model systems show rate enhancement and some selectivity in vitamin B6-dependent reactions, but they are still primitive compared with the real enzymes. We expect to see improved reaction rates and selectivities in future generations of vitamin B6 enzyme models. An additional goal, which has not received ade-... [Pg.60]

In order to describe the properties of real fluids, it is common to define certain auxiliary functions for the representation of the real behavior. One important auxiliary function is the compressibility factor z ... [Pg.17]

We view the real or the simulated system as a black box that transforms inputs into outputs. Experiments with such a system are often analyzed through an approximating regression or analysis of variance model. Other types of approximating models include those for Kriging, neural nets, radial basis functions, and various types of splines. We call such approximating models metamodels other names include auxiliary models, emulators, and response surfaces. The simulation itself is a model of some real-world system. The goal is to build a parsimonious metamodel that describes the input-output relationship in simple terms. [Pg.288]

Response functions. The elementary Cooper and Peierls logarithmic divergences (19) of the interacting electron gas are also present order by order in the perturbation theory of response functions in the 2kf density-wave and superconducting channels. A scaling procedure can thus be applied in order to obtain the asymptotic properties of the real part of the retarded response functions which we will note Xm.( )- is convenient to introduce auxiliary response functions noted x ( ) [107], which are defined... [Pg.243]

We have now come to the discussion of the central equations which form the basis of almost any practical application of density functional theory the Kohn-Sham equations. Kohn and Sham [8] introduced an auxiliary noninteracting system of particles with the property that it yields the same ground state density as the real interacting system. In order to put the Kohn-Sham procedure on a rigorous basis we introduce the functional... [Pg.73]

Therefore, BA can be seen as a productivity function that should be maximised by design. For example, the excess of reactant can give higher stoichiometric yield RY, but lower real balance yield BA. Increasing EAp to the theoretical limit of one is an objective of process design. This can be achieved by replacing steps involving unrecoverable auxiliary chemicals with operations where the recycle of materials is possible. [Pg.25]

All the essential auxiliary plant functions were completed in a timed sequence to limit plant temperature transients to a minimum. Alarms and flashing indications had to be accepted by the operator, and reactor conditions gradually subsided in real time, finally to allow the boilers to be dried out and the low power decay heat loops to be introduced manually. [Pg.136]

Depending on the focus of the study, the functional unit varies for the different studies. In all smdies, the manufacmring of the fuel cell itself is included. Input and output data are related to a 1 kWei fuel cell stack, distinguished in mbular or planar cell concepts. The Real-SOFC study focuses exclusively on the stacks, accompanying the research activities performed in this project. The other smdies include the Balance of Plant (BoP) and auxiliary components as well. All other studies expand the investigated life cycle by integrating the use phases as well, thus defining 1 kWh of electricity produced as the basis for comparison. [Pg.776]

Unfortunately, it is very hard to obtain the density of an interacting system. To circumvent this problem, Kohn and Sham introduced an auxiliary system of non-interacting particles [7]. The dynamics of these particles are governed by a potential chosen such that the density of the Kohn-Sham system equals the density of the interacting system. This potential is local (multiplicative) in real space, but it has a highly non-local functional dependence on the density. In non-mathematical terms this means that the... [Pg.147]

Density functional theory would never have played the important role it has now assumed in molecular quantum chemistry without the proof of an additional theorem, provided by Kohn and Sham (KS). They proved that it is possible to construct an auxiliary reference system of noninteracting electrons that has exactly the same electron density p(r) as that of the real system of interacting electrons. According to the HK theorem, this implies that there must be an associated potential "0 r) in which the noninteracting electrons move, according to a wavefunction which yields the same electron density as that in the real system. Since F describes a system of noninteracting electrons, it can be formulated as a Slater determinant, the MOs in which may be described as linear combinations of atomic orbitals. [Pg.41]

The first such process is a variant of the oxacyclo-propanation reaction discussed in Section 12-10, as applied specifically to 2-propenyl (allylic) alcohols. However, instead of a peroxycarboxylic acid, the reagent is ferf-butyl hydroperoxide in the presence of titanium (TV) isopropoxide ( Sharpless epoxidation ), the function of the chiral auxiliary being assumed by tartaric acid diethyl ester (Real Life 5-3). The naturally occurring (-l-)-[2/ ,3/ ]-diethyl tartrate and its nonnatural (—)-(25,35) mirror image are both commercial products. One delivers oxygen to one face of the double bond, the other to the opposite face, as shown below, giving either enantiomer of the oxacyclopropane product with high enantiomer excess (Section 5-2). [Pg.512]


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See also in sourсe #XX -- [ Pg.16 ]




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Auxiliary function

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