Vogel constant

Other polymers, as typified by poly(3,3-dimethyl thietane), show maxima in the overall crystallization rate.(218) The data can be analyzed in a manner comparable to that described for spherulite growth rates and the conclusions are the same. Whether a transition from Regime II to III is discerned depends on the values taken for the Vogel constants. 

G. Kortum, W. Vogel, and K. Andmssow, Dissociation Constants of Organic A.cids inA.queous Solution, Butterworths, London, 1961. 

Biquinolyl (a,a -diquinolyl) [119-91-5] M 256.3, m 196 , pKe, 4.2. Decolorised in CHCI3 soln (charcoal), then crystd to constant melting point from EtOH or pet ether [Cumper, Ginman and Vogel J Chem Soc 1188 1962]. 

Krishnaswami S, Graustein WC, Turekian KK, Dowd F (1982) Radium, thorium, and radioactive lead isotopes in groundwaters application to the in-situ determination of adsorption-desorption rate constants and retardation factors. Water Resour Res 6 1663-1675 Krishnaswami S, Bhushan R, Baskaran M (1991) Radium isotopes and Rn in shallow brines, Kharaghoda (India). Chem Geol (Isot Geosci) 87 125-136 Kronfeld J, Vogel JC, Talma AS (1994) A new explanation for extreme " U/ U disequilibria in a dolomitic aquifer. Earth Planet Sci Lett 123 81-93... 

In spite of the problems associated with the static structure, the coarsegrained model for BPA-PC did reproduce the glass transition of this material rather well the self-diffusion constant of the chains follows the Vogel-Fulcher law [187] rather nicely (Fig. 5.10),... 

Fig. 5.10. Plot of the inverse logarithm of the self-diffusion constant of BPA-PC, for a length N = 20 of the coarse-grained chains, vs. temperature. Straight line indicates the Vogel-Fulcher [187] fit. From [28]...

Fig. 6.4. Vogel-Fulcher plot of the chain diffusion constants D for the three different polycarbonate modifications, as indicated in the figure, for N = 20 model monomers...

Applying this prediction to the cooling rate dependence of a break points in the specific volume curves, one obtains a Vogel-Fulcher temperature of To = 0.35 that agrees well with that determined from the temperature dependence of the diffusion constant in this model, which is T = 0.32. 

Kortum, G. Vogel, W. Andrussow, K. "Dissociation Constants of Organic Acids in Aqueous Solution" ... 

Kortiim and Vogel (1955) drew attention to the fact that the spectroscopic determination of the K-values suffered from a degree of uncertainty because of the unknown extinction coefficients of the complexes. For this reason, the authors preferred to determine the constant by means of a solubility method which had already proved of value in analogous investigations of the systems dioxan-iodine and methyl butyl ether-iodine (Kortiim and Kortiim-Seiler, 1950). In this method the solubility of iodine is determined as a function of the composition of solvent mixtures. values obtained by this method are summarized in Table 13. 

These results are important because the measurements are of greater accuracy than optical measurements of these systems. The eflFeot of the solvent on these constants was also discussed in detail (Kortiim and Vogel, 1955). 

Use matrix manipnlations to solve for the three constants in the Vogel-Fnlcher-Tammann nsing the data in Cooperative Learning Exercise 4.1. Show yonr work. 

Chloroquinoline [612-62-4] M 163.6, m 34°, b 147-148°/15mm, d 1.2351, n 1.62923. Purified by crystn of its picrate to constant melting point (123-124°) from benzene, regenerating the base and distilling under vacuum [Cumper, Redford and Vogel JCS 1183 7962]. 2-Chloroquinoline can be crystd from EtOH. Its picrate has m 122° (from EtOH). 

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