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Expansion results

In a good solvent, the end-to-end distance is greater than the 1q value owing to the coil expansion resulting from solvent imbibed into the domain of the polymer. The effect is quantitatively expressed in terms of an expansion factor a defined by the relationship... [Pg.62]

The clinical use of plasma products varies widely between countries (Table 8) with commercial products being imported in some instances to meet demand. In the United States, the market for plasma products increased from 250,000,000 in 1980 to over 850,000,000 in 1991. This expansion resulted from a 60% increase in the use of albumin, a 70% increase in the use of Eactor X concentrate, and the introduction of intravenous immunoglobulin (IgG iv). The 1987 quantity of IgG iv was 10.7 kg per million population by 1991 this usage had increased approximately 220%. The introduction of highly... [Pg.533]

In a foam where the films ate iaterconnected the related time-dependent Marangoni effect is mote relevant. A similar restoring force to expansion results because of transient decreases ia surface concentration (iacteases ia surface tension) caused by the finite rate of surfactant adsorption at the surface. [Pg.464]

In a work-producing expansion, the temperature of the process fluid is always reduced hence, coohng does not depend on being below the inversion temperature prior to expansion. Additionally, the work-producing expansion results in a larger amount of coohng than in an isenthalpic expansion over the same pressure difference. [Pg.1129]

K.—Ordinarily the intrinsic viscosity should depend on the molecular weight not only owing to the factor occurring in Eq. (26), but also as a result of the dependence of the factor on M. The influence of this expansion resulting from intramolecular interactions may be eliminated by suitable choice of the solvent and temperature. Specifically, in an ideal solvent, or -solvent, a = l and Eq. (26) reduces to... [Pg.612]

Scheme 10.3 gives some examples of pinacol and related rearrangements. Entry 1 is a rearrangement done under strongly acidic conditions. The selectivity leading to ring expansion results from the preferential ionization of the diphenylcarbinol group. Entry 2, a preparation of 2-indanone, involves selective ionization at the benzylic alcohol, followed by a hydride shift. [Pg.888]

On macroscopic length scales, as probed for example by dynamic mechanical relaxation experiments, the crossover from 0- to good solvent conditions in dilute solutions is accompanied by a gradual variation from Zimm to Rouse behavior [1,126]. As has been pointed out earlier, this effect is completely due to the coil expansion, resulting from the presence of excluded volume interactions. [Pg.87]

Replacing the generalized strain e with strain components X4 and Xg and adding the elastic energy term in the Landau expansion results in equation 5.175. [Pg.357]

The different types of admixtures, known to reduce alkali-aggregate reactions, can be divided into two groups those that are effective in reducing the expansion due to the alkali-silica reaction, and those that lower expansions resulting from the alkali-carbonate reaction. For the alkali-silica reaction, reductions in the expansion of mortar specimens have been obtained with soluble salts of lithium, barium and sodium, proteinaceous air-entraining agents, aluminum powder, CUSO4, sodium silicofluoride, alkyl alkoxy silane,... [Pg.306]

For magnet configurations in which coils are coaxial and symmetric about the illustrated xy-plane, such as the magnet configurations in Figure 2A and C, the spherical harmonic expansion results in the elimination of all even order terms within the expansion. To further reduce computational complexity, the strategy employed here considers only one quarter of the magnet domain, and thus, the constraints in Equation (5) simplify to ... [Pg.171]

Alefeld and co-workers (24, 25) have discussed the hydrogen-hydrogen attractive interaction by using the elasticity theory developed for defects in solids by Eshelby and others (46). The strength of the elastic dipole moment is related to the volume expansion resulting from the interstitial hydrogen (25) (Equation 10), where P is the strength of the elastic dipole caused by the interstitial species... [Pg.301]

The Joule-Thomson coefficient is the slope of the isenthalpic lines in the P-T projection. In the region where iJt<0, expansion through the valve (a decrease in pressure) results in an increase in temperature, whereas in the region where pJt >0, expansion results in a reduction in temperature. The latter area is recommendable for applying the PGSS process. [Pg.597]

The formation volume factors of gas-saturated brines have been correlated in a manner similar to an early oil formation volume factor correlation.2 Figure 16-5 illustrates the correlation procedure. A volume of Bw barrels of brine at reservoir conditions is converted to Vj barrels of brine by the reduction in pressure to 14.65 psia. Normally, Vi is larger than Bw because the expansion resulting from pressure reduction is greater than the reduction in liquid volume resulting from the evolution of gas. The Vi barrels of brine are converted to 1 barrel of brine at surface conditions by the reduction in temperature from reservoir temperature to 60°F. [Pg.446]

A gas-phase equilibrium responds to compression—a reduction in volume—of the reaction vessel. According to Le Chatelier s principle, the composition will tend to change in a way that minimizes the resulting increase in pressure. For instance, in the formation of NH3 from N2 and H2, 4 mol of reactant molecules produces 2 mol of product molecules. The forward reaction therefore decreases the number of molecules in the container and hence the pressure. It follows that, when the mixture is compressed, the equilibrium composition will tend to shift in favor of product, because that minimizes the increase in pressure (Fig. 9.12). Expansion results in the opposite response, a tendency for products to decompose. Haber realized that to increase the yield of ammonia, he needed to carry out the synthesis with highly compressed gases. The actual industrial process uses pressures of 250 atm and more (Fig. 9.13). [Pg.577]

On irradiation, 3,4-dihydropyrene epoxide 475 undergoes a ring expansion, resulting in tribenzo[bcd]oxepine 476 (79T1059). [Pg.80]

These results show that the minimal subtraction scheme eliminates ambiguities inherent in an extrapolation of e-expansion results to physical dimension d = 3. For the flow equations no extrapolation is necessary. Furthermore they are strictly independent of the parameter bu(z). [Pg.214]

This quantity will be analyzed in detail in Sect. 15.4. The e-expansion result reads... [Pg.219]


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