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Integral of configuration

In Silicalite. A variety of papers are concerned with sorption of methane in the all-silica pentasil, silicalite. June et al. (87) used a Metropolis Monte Carlo method and MC integration of configuration integrals to determine low-occupancy sorption information for methane. The predicted heat of adsorption (18 kJ/mol) is within the range of experimental values (18-21 kJ/ mol) (145-150), as is the Henry s law coefficient as a function of temperature (141, 142). Furthermore, the center of mass distribution for methane in silicalite at 400 K shows that the molecule is delocalized over most of the total pore volume (Fig. 9). Even in the case of such a small sorbate, the channel intersections are unfavorable locations. [Pg.66]

A disciplined approach must be sustained to maintain the integrity of configuration management. It can be tempting to relax configuration management just to release resources and reduce costs. Consequential problems that often arise include ... [Pg.85]

We can establish a general form for the integral of configuration in the case of pairwise interactions. [Pg.96]

The ti eatment of the Jahn-Teller effect for more complicated cases is similar. The general conclusion is that the appearance of a linear term in the off-diagonal matrix elements H+- and H-+ leads always to an instability at the most symmetric configuration due to the fact that integrals of the type do not vanish there when the product < / > / has the same species as a nontotally symmetiic vibration (see Appendix E). If T is the species of the degenerate electronic wave functions, the species of will be that of T, ... [Pg.589]

In an ideal gas there are no interactions between the particles and so the potential ener function, 1 ), equals zero. exp(- f (r )/fcBT) is therefore equal to 1 for every gas partic in the system. The integral of 1 over the coordinates of each atom is equal to the volume, ai so for N ideal gas particles the configurational integral is given by (V = volume). T1 leads to the following result for the canonical partition function of an ideal gas ... [Pg.427]

Here r(t) is the stress at a fluid particle given by an integral of deformation history along the fluid particle trajectory between a deformed configuration at time f and the current reference time t. [Pg.13]

Fiber and Karplus [38] presented an effective set of numerical methods for computing the reaction paths based on this approximation. First the path is discretized—it is expressed as a chain of intermediate configurations of the system rj,. The line integrals of Fq. (19) are then written as... [Pg.211]

Another common type of compressor is manufactured in an integrally geared configuration. It is basically an overhung style machine mounted on a gear box and uses the gear pinion shaft extension to mount an... [Pg.134]

The chemical reactions through cyclic transition states are controlled by the symmetry of the frontier orbitals [11]. At the symmetrical (Cs) six-membered ring transition state of Diels-Alder reaction between butadiene and ethylene, the HOMO of butadiene and the LUMO of ethylene (Scheme 18) are antisymmetric with respect to the reflection in the mirror plane (Scheme 24). The symmetry allows the frontier orbitals to have the same signs of the overlap integrals between the p-or-bital components at both reaction sites. The simultaneous interactions at the both sites promotes the frontier orbital interaction more than the interaction at one site of an acyclic transition state. This is also the case with interaction between the HOMO of ethylene and the LUMO of butadiene. The Diels-Alder reactions occur through the cyclic transition states in a concerted and stereospecific manner with retention of configuration of the reactants. [Pg.17]

The product of the overlap integrals of the cyclically interacting configurations, G, E, and is then approximately expressed as... [Pg.230]

The overlap integrals of the configurations S) are approximately related to the orbital overlaps, s, i.e. [29]... [Pg.232]

We discovered a complementary procedure for conversion of OMen to other functional groups. The ester P-OMen bond was shown to be cleaved in a stereoselective manner reductively [85,86]. The cleavage takes place with almost complete preservation of stereochemical integrity at phosphorus. The reducing agents are usually sodium or Hthium naphthalenide, lithium biphenyUde, and Hthium 4,4 -di-fert-butylbiphenyl (LDBB). The species produced is then quenched with an alkyl hahde or methanol to afford tertiary or secondary phosphines, respectively (Scheme 5b). Overall, the displacement reaction proceeds with retention of configuration. [Pg.13]

Preconfigured LIMS— This LIMS does not require extensive customer programming. To meet specific needs of end users, the vendors provide a comprehensive suite of configuration tools. These tools allow end users to add new screens, menus, functions, and reports in a rapid and intuitive manner. The tools also allow the LIMS to be more easily integrated with other business applications such as document processing, spreadsheets, and manufacturing systems. [Pg.59]

As with organomagnesium reagents, there is usually loss of stereochemical integrity at the site of reaction during the preparation of alkyllithium compounds.25 Alkenyllithium reagents can usually be prepared with retention of configuration of the double bond.26,27... [Pg.624]

Configurational integrity of secondary alkylzinc reagents had been demonstrated by Knochel although the preparation of the zinc reagent was not practical (Scheme 8.8) [13],... [Pg.228]

Scheme 8.8 Knochel s precedent for configurational integrity of organozinc reagents. Scheme 8.8 Knochel s precedent for configurational integrity of organozinc reagents.

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See also in sourсe #XX -- [ Pg.96 ]




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