Alternating temperature

Again, for a given mixture and pressure, temperature is searched to satisfy Equation 4.59. Alternatively, temperature is specified and pressure searched for the dew pressure. 

Thus, to calculate the bubble point for a given mixture and at a specified pressure, a search is made for a temperature to satisfy Equation 4.58. Alternatively, temperature can be... 

How are the energy transfer requirements for the process best accomplished Should one operate isothermally, adiabatically, or in accord with an alternative temperature protocol ... 

TSA [Thermal (or Temperature) swing adsorption] A method for separating gases by cyclic adsorption and desorption from a selective adsoibent, at alternating temperatures. Less commonly used than PSA. 

Miles JE, Nishimoto RK, Kawabata O (1996) Diurnally alternating temperatures stimulate sprouting of purple nutsedge (Cyperus rotundus) tubers. Weed Sci 44 122-125 Miles JE, Kawabata O, Nishimoto RK (2002) Modeling purple nutsedge sprouting undersoil solarization. 

Temperature should be strictly controlled in the microwave oven with a temperature probe that has a feedback mechanism to regulate the energy output of the microwave oven and thus maintains the optimal temperature. Alternatively, temperature can be controlled by placing a water load in the chamber of the microwave oven, which absorbs extra energy and provides humidity, slowing the evaporation of reagents. In addition, hot spots in the chamber should be avoided by using the neon bulb display method (Chapter 5). 

If passed through a reaction mixture, a sound wave causes a wave of alternating temperatures which calls for a corresponding wave of new equilibrium positions to be set up. If the concentrations of species involved in the equilibria can alter rapidly enough to enable each new equilibrium position to be set up as each new temperature is attained, then the concentrations and the equilibria can keep in phase with the periodic displacement. This occurs when the period of the sound wave is large compared with the relaxation time. 

Kebreab, E. and Murdoch, A. J. 1999. A model of the effects of a wide range of constant and alternating temperatures on seed germination of four Orobanche species. Ann. Bot. 84, 549-557... 

Figure 7.25. Time courses of acclimation for three behavioral traits (temperatures at which coma, loss of equilibrium, and hyperexcitability occurred) and synaptosomal fluidity in goldfish (Carassius auratus). Fish were first acclimated to either 5°C or 25°C and then transferred to the alternate temperature. (Modified after Cossins et al., 1977.)...

The ability to calculate Rll (or rgd) f°r all polymers by inserting V(298K) and n(298K) values predicted via independent correlations into Equation 8.7 (or 8.8) is very useful. If n(T) needs to be predicted at an alternative temperature, Rll (or Rgd) values calculated in this manner can be inserted into Equation 8.5 (or 8.6), along with V(T) values calculated by using the equations listed in Section 3.D, to predict n(T) for T 298K. 

A sound wave is passed through an electrolyte solution in which there are species present at equilibrium. This is done over a range of frequencies of the sound wave, and the absorption of sound energy by the solution, or the velocity of the sound wave is measured for each frequency. The sound wave is equivalent to a pressure wave or to a series of alternating temperatures, and these call for a corresponding wave of new equilibrium positions to be set up. 

Figure 6.22. The output of a white light source is modulated with a variable-frequency beam chopper so that a square wave is produced which illuminates one surface of the sample. The fluctuating alternating temperature is measured on the other surface using a thermocouple. Figure 6.23 shows the variation in Fac as a function of time for materials of large and small heat capacity. Owing to recent improvements...

In ACC the sample is illuminated by a white light source whose output is modulated to produce a square wave. Schematic alternating temperature, as a function of time, for materials of (II) small and (III) large heat capacity... 

Alternating current calorimeter Instrument for measuring the alternating temperature change produced in a substance by an alternating heating current. 

Nagao, A. (1983) Differences of flower initiation of Cryptomeria japonica under various alternating temperatures. J. Jap. For. Soc., 65 335-338 (in Japanese). 

Okamoto Y, Kinoshita A, Satake T. 2001. Enhancement of the frequency of callus formation and plant regeneration from rice anther culture by alternating temperature. Breed Res 3 87 - 94 (in Japanese). 

For most substances, the values of standard entropies are not available for a wide range of temperatures. Most commonly, tables present only data at 25°C. For most purposes, it is sufQcient to use the standard entropies at 25°C to calculate reaction entropy changes at other temperatures because A5 rxr does not generally depend highly on temperature. If accurate work is needed, however, or if the temperature of interest is well removed from the temperature for which data are available, it is necessary to correct the tabulated values for the change in temperature. To do this, we can use a procedure analogous to that outlined in Section 7.7 for the calculation of AT/j n at alternate temperatures. 

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