Softening kinetics

Solomon, W. K., Jindal, V. K. (2003b). Modeling thermal softening kinetics of potatoes using fractional conversion of rheological parameters. J. Texture Stud., 34, 231-247. 

Figure 10.59 Sorption kinetics of micro-emulsion cationic softener formulation at different temperatures on cotton fabric [484], Initial concentration 3 g/kg fibre, liquor ratio 15 1...

The available kinetic and thermochemical data are summarized in Table 7. Based on the approximate equality of E and D1+D2 and on the magnitude of the frequency factor, Billinge and Gowenlock98 would place dimethyl mercury, di-B-propyl mercury, di-isopropyl mercury (above 230 °C) and (on the basis of the frequency factor only, since thermochemical data are not available) di-n-butyl mercury in class II (simultaneous rupture into mercury and two alkyl radicals). If the high frequency factors are simply due to a general softening of the vibrations in the activated state, then in the case of di-isopropyl mercury D2 — 0, while for dimethyl and di-B-propyl mercury D2 is small but finite (2-3 kcal.mole" ). However, within the limits of experimental error all of these alkyls for which thermochemical data are available may have E = Dl+D2, and thus all may belong to class II. At the same time it must be noted that some metal alkyls which are... 

The decomposition kinetics were also calculated by Usmanov and Magarra 287) using a dimensionless molecular transfer equation. Perchloryl fluoride can be heated almost to the softening point of glass without explosion 92). 

Second, friction during CMP generates heat that can affect the reaction kinetics as well as soften the polish pad. On most tools, heat transfer away... 

Alvarez, M. D., Canet, W. (2000a). Kinetics of softening of potato tissue by temperature fluctuations in frozen storage. Fur. Food Res. Techrwl., 210,273-279. 

Bourne, M. C. (1987). Effect of blanch temperature on kinetics of thermal softening of carrots and green beans. 

Bourne, M. C. (1989). Applications of chemical kinetic theory to the rate of thermal softening of vegetable tissue. In J. J. Jen (Ed.), Quality factors of fruits and vegetables. Chemistry and technology (pp. 98-110). American Chemical Society, Washington, Chap 9. 

Bourne, M. C. (1995). Kinetic of softening of carrot by gamma radiation. J. Texture Stud., 26, 553-560. 

Rahardjo, B., Sastry, K. (1993). Kinetics of softening of potato tissue during thermal treatment. Trans. 1. ChemE., 77,235-241. 

Table 9.7 Fractional and first-order kinetic parameters for softening of potato...

The best fit occurs at 7/. values 50°C below the respective values of Tg for each of these values of a. Tg was determined by advancing the reaction to a particular value of a based on the time-temperature DSC kinetic data. The softening temperature, Tg, was determined from the onset of the drop in G. ... 

The most striking feature of the stress softening phenomenon of thermoelastoplastics is its complete reversibility under certain conditions, consisting in a reformation process in the stress-free state which involves healing of cracks and reaching the initial integrity of the hard phase 119,120,12 ). The reformation kinetics in stress-softened samples indicates that this process is controlled by diffusion. 

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