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Independent selection

In terms of the derived general relationships (3-1) and (3-2), x, y, and h are independent variables—cost and volume, dependent variables. That is, the cost and volume become fixed with the specification of dimensions. However, corresponding to the given restriedion of the problem, relative to volume, the function g(x, y, z) =xyh becomes a constraint funedion. In place of three independent and two dependent variables the problem reduces to two independent (volume has been constrained) and two dependent as in functions (3-3) and (3-4). Further, the requirement of minimum cost reduces the problem to three dependent variables x, y, h) and no degrees of freedom, that is, freedom of independent selection. [Pg.441]

Any combination of first-order reactions can be simulated by extension of this procedure. Reversible reactions add only the feature that reacted species can be regenerated from their products. Second-order reactions introduce a new factor, for now two molecules must each be independently selected in order that reaction occur in the real situation the two molecules are in independent motion, and their collision must take place to cause reaction. We load the appropriate numbers of molecules into each of two grids. Now randomly select from the first grid, and then, separately, randomly select from the second grid. If in both selections a molecule exists at the respective selected sites, then reaction occurs and both are crossed out if only one of the two selections results in selection of a molecule, no reaction occurs. (Of course, if pseudo-first-order conditions apply, a second-order reaction can be handled just as is a first-order reaction.)... [Pg.112]

Examples of dehydrobromination leading to bromoethynylpyrazoles as illustrated by Scheme 36 are described in a patent (99USP5925769). Treatment of 1,1-dibromooleflns with tetrabutylammonium fluoride in THE at room temperature for about 24 h under N2 gives the l-bromo-2-(pyrazol-3-yl)acetylenes where R, R, R, and R" are independently selected from H and alkyl, alkoxy. [Pg.18]

X a chain of a combined total of "n" carbon or heteroatoms to serve to complete a 5, 6, 7 member ring Y an independently selected substituent, two of which may join to form fused rings... [Pg.341]

Rf-Rio independently selected as hydrogen or substituents provided that any of the indicated substituents may join to form further fused rings. [Pg.341]

A light source used frequently for ultraviolet absorption studies is the deuterium lamp. If an instrument is meant strictly for ultraviolet work, then the deuterium lamp is the only light source present and the instrument is called a UV spectrophotometer. Often, both a tungsten filament lamp and a deuterium lamp are present and are individually selectable. Also, instead of having two independently selectable... [Pg.205]

Mannich reactions give rise to (i-amino carbonyl compounds which are amenable to further synthetic manipulations. Numerous stereoselective variants have been achieved by means of different types of catalysts including both metal complexes and organic molecules. In 2004, the groups of Akiyama and Terada independently selected this transformation as a model reaction for the introduction of a novel chiral motif to asymmetric catalysis [14, 15]. [Pg.399]

Using the monomolecular rate theory developed by Wei and Prater, we have analyzed the kinetics of the liquid-phase isomerization of xylene over a zeolitic catalyst. The kinetic analysis is presented primarily in terms of the time-independent selectivity kinetics. With the establishment of the basic kinetics the role of intracrystalline diffusion is demonstrated by analyzing the kinetics for 2 to 4 zeolite catalyst and an essentially diffusion-free 0.2 to 0.4 m zeolite catalyst. Values for intracrystalline diffusivities are presented, and evidence is given that the isomerization is the simple series reaction o-xylene <= m-xylene <= p-xylene. [Pg.537]

The integration of capital expenditures for the shared resources as shown in equation (3.11a) rests on the assumption that the number of equipments is correlated to the number of production lines. If the model can independently select the shared resource capacity, it is theoretically possible that the number of shared resources operated increases while the number of production lines used decreases. In this case a separate calculation of the investment expenditures for shared resources is required to avoid that "negative" capital expenditures from capacity reductions that are eliminated via the non-negativity constraint (3.54) offset the expenditures for shared resource installations. [Pg.115]

Where Rj and R2 are each independently selected from a group consisting of hydrogen, methyl and ethyl. [Pg.181]

CH C and D are carbon and together, with a three atom linker makes a third ring where said linker is -CH=CH-NR3- or -CH=CH-S- X is C or N Y is a bond Z is phenyl, naphthyl, thiophenyl or benzofuranyl and R and R2are each independently selected from hydrogen and Ci.3 alkyl,... [Pg.258]

Reactivity-selectivity relationships are obtainable in carbene chemistry provided an independent selectivity parameter is found. Under such circumstances the relative rate data then serve as a measure of relative reactivity. This has been done with a number of Hammett studies. Thus the addition of dichlorocarbene to compounds [ 1 ] — [3] (listed in Table 15) indicates that a reactivity-selectivity relationship is obtained using p as a measure of selectivity. A more reactant-like transition state is obtained for the more reactive substrate in accordance with the Leffler- Hammond postulate. [Pg.113]

Since the temperature difference T - Tf at any point in the flow will depend on the overall temperature difference (Tw — Tf) it is seen that a convenient measure of the buoyancy force acting on the fluid is figp(Tw - T/). However, p has already been independently selected as a variable on which h depends so the variable that will be used as a measure of the buoyancy force will be taken as ... [Pg.15]


See other pages where Independent selection is mentioned: [Pg.584]    [Pg.552]    [Pg.217]    [Pg.229]    [Pg.362]    [Pg.152]    [Pg.157]    [Pg.217]    [Pg.317]    [Pg.100]    [Pg.233]    [Pg.97]    [Pg.8]    [Pg.144]    [Pg.147]    [Pg.147]    [Pg.153]    [Pg.218]    [Pg.309]    [Pg.552]    [Pg.430]    [Pg.430]    [Pg.432]    [Pg.435]    [Pg.181]    [Pg.15]    [Pg.84]    [Pg.332]    [Pg.714]    [Pg.206]   
See also in sourсe #XX -- [ Pg.147 ]




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