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Production R-

If the DHT is evaluated numerically from its defining expression, the time taken for long data sequences of length N is proportional to as with the DFT, because for each value of v the are N evaluations of the product /(r)cas(2nvT/ N) and there are N values of v. [Pg.182]

Dte that the vector product r2 x r is not the same as the vector product r x r2, as it rresponds to a vector in the opposite direction. The vector product is thus not commutative. [Pg.32]

Electrolysis, under similar conditions, of a mixture of two carboxylic acids RCOOH and R COOH leads, in addition to normal coupling products R—R and R —R, to cross coupling R—R. If a mixture of a saturated carboxylic acid and a half ester of an ato-dicarboxylic acid is electrolysed, there are three main products, viz., a hydrocarbon (I), a mono-ester (II), and a di-ester (HI) and these are readily separable by distillation. Some unsaturated ester (IV) is often present in small quantity. [Pg.938]

An interesting outgrowth of these considerations is the idea that In r versus K or Vj should describe a universal calibration curve in a particular column for random coil polymers. This conclusion is justified by examining Eq. (9.55), in which the product [i ]M is seen to be proportional to (rg ), with r = a(rg 0 ) - This suggests that In rg in the theoretical calibration curve can be replaced by ln[r ]M. The product [r ]M is called the hydrodynamic volume, and Fig. 9.17 shows that the calibration curves for a variety of polymer types merge into a single curve when the product [r ]M, rather than M alone, is used as the basis for the cafibration. [Pg.649]

Prevalence of treatment occurring in product R = rare to occasional F = frequent W = widespread or near-total. [Pg.221]

Diafiltration If a batch process is run so that the permeate is replaced by an equal volume of fresh solvent, unretained solutes are flushed through the system more efficiently. A major use of UF is fractionation, where a solvent, a retained solute and an unretained solute are present. An example is whey, containing water, protein, and lactose. If the retention of protein is I and the retention of lactose is 0, the concentration of protein in the retentate rises during UF. The ratio of protein to lac tose rises, but the feed concentration of lactose is unchanged in retentate and permeate. Diafiltration dilutes the feed, and permits the concentration of lactose to be reduced. Diafiltration is used to produce high-purity products, and is used to fractionate high-value products. R is always 0 for eveiy component. [Pg.2042]

Consider tlie ntli-order irreversible reaction of the form A —> products, (-r ) = kC, in a constant density single-stage CESTR. If n = 1, Equation 5-158 becomes... [Pg.315]

Although the radical-pair is largely held together by small amounts of the intermolecular coupling product R-... [Pg.263]

When either the reactant (O) or product (R) is adsorbed (but not both), one expects to observe a postpeak or prepeak, respectively (at potentials more negative or positive than the diffusion-controlled peak). [Pg.38]

Although the addition of carbon monoxide to a carbonium ion R+ leads to a product R—C =0, with a new carbon-carbon bond, one may raise the question whether this oecurs by direct alkylation at carbon ... [Pg.50]

Table 4. Calculated theoretical yields for mixed coupling products R- R... Table 4. Calculated theoretical yields for mixed coupling products R- R...
An alcohol is an example of a compound which does not react with a 2-bromoamide, in the absence of a promoter. Representative reactions (Fig. 3), with methanol in the presence of Ag20, gave an (S)-O-methyllactamide 4 rapidly and with retention of configuration. To explore if an alternative stereochemistry was available and to have indirect information on the role of Ag20, reactions were also run between methanol and a 2-bromoamide, in the presence of Ag+CF3S03 . The inversion product (R)-0-methyllactamide was obtained rapidly, with high yield (ref. 10). [Pg.162]

The radicals do not drift apart because they are held together by the solvent cage. According to this mechanism, the radicals must recombine rapidly in order to account for the fact that does not racemize. Other evidence in favor of mechanism a is that in some cases small amounts of coupling products (R R have been isolated,which would be expected if some R leaked from the solvent cage. However, not all the evidence is easily compatible with mechanism a. It is possible that another mechanism (b) similar to mechanism a, but involving ion... [Pg.1420]

By the year 2000, advances in computer technology coupled with business and societal driving forces will indeed have a significant impact on applied polymer science R D. The focus will have shifted from implementation of new computer technology to extensive application in product R D and problem solving. [Pg.2]

In Table I are listed the radical products (R )(column 2), AE(x) values (column 3), EA values (column 4) and the experimental temperatures for the one- and ten hour half life rates for the decomposition of trona-symmetric bisalkyl diazenes (columns 5 and 6), (rona-phenyl,alkyl diazenes (columns 7 and 8), peresters (columns 9 and 10) and hydrocarbons (columns 11 and 12). [Pg.419]

Recently, enantioselective organo-catalytic procedures for the aza-Henry reaction have been disclosed. The presence of either an acidic or a basic function appears to be a requisite of the catalyst. In fact, the condensation of ni-tromethane with M-phosphinoyl arylimines 72 is catalyzed by the chiral urea 85 derived from (R,R)-l,2-diaminocyclohexane and gives the product (R)-74 with good yield and moderate enantioselectivity (Scheme 15) [50]. The N-phosphinoyl substituent is determinant, as the addition of nitromethane to the N-phenyl benzaldimine failed and the reaction of the N-tosyl ben-zaldimine gave the expected adduct with quantitative yield but almost no... [Pg.18]

A detailed mathematical treatment gave the following models for the main substrate (A) and product (R) ... [Pg.183]

Figure 10.5 shows the basic concept of the particle-level MR that gives (i) selective addition of reactants to the reaction zone and (ii) selective removal of products from the reaction zone. In the first case, if the diffusivity of one reactant (A) is much higher than that of the other components (B), the reactant (A) selectively diffuses into a catalyst particle through a membrane. Undesired reactions or the adsorption of poisons on the catalysts can be prevented. In the second case, the reaction has a hmited yield or is selectivity controlled by thermodynamics. The selective removal of the desired product from the catalyst particle gives enhancement of selectivity when the diffusivity of one product (R) is much greater than that of the other products (S). [Pg.218]

The environment for pharmaceutical R D is changing, with the main challenge stemming from decreasing R D productivity. R D costs are increas-... [Pg.248]

Ethylene oxide is an important intermediate for ethylene glycol (antifreeze) and for plastics, plasticizers, and many other products [R.A. van Santen and H.P.C.E. Kui-pers, Adv. Catal. 35 (1987) 265]. In Chapter 1 we explained that the replacement of the traditional manufacturing process - which generated 1.5 mole of byproducts per 1 mole of epoxide - by a catalytic route based on silver catalysts is a major success story with respect to clean chemistry (Fig. 9.16). [Pg.370]

Here the point p belongs to the spherical surface A of radius R. In order to find the upper limit on the left hand side of this equality, let us recall that T is the disturbing potential. In other words, it is caused by the irregular distribution of masses whose sum is equal to zero. This means that its expansion in power series with Legendre s functions does not contain a zero term. The next term is also equal to zero, because the origin coincides with the center of mass. Therefore, the series describing the function T starts from the term, which decreases as r. This means that the product r T O if oo and... [Pg.126]

The following reaction system of industrial importance was studied a liquid reactant A simultaneously reacts with a liquid B and a gas G to give products R and S and by-products lumped as L. For proprietary reasons, the names of the species are not specified. The reaction is carried out in semibatch mode. The amounts of A, B, G, R, and S at the end of experiments leading to identification of the kinetic model were determined analytically while the amount of L was evaluated from the material balance. [Pg.326]

The objective of optimization was to maximize the amount of product R within as short a time as possible by manipulating the following variables ... [Pg.326]


See other pages where Production R- is mentioned: [Pg.29]    [Pg.45]    [Pg.2158]    [Pg.157]    [Pg.676]    [Pg.466]    [Pg.507]    [Pg.2212]    [Pg.352]    [Pg.445]    [Pg.131]    [Pg.170]    [Pg.182]    [Pg.6]    [Pg.328]    [Pg.147]    [Pg.143]    [Pg.793]    [Pg.282]    [Pg.34]    [Pg.49]    [Pg.143]    [Pg.143]    [Pg.425]    [Pg.17]    [Pg.353]   
See also in sourсe #XX -- [ Pg.133 ]




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