Heat, capacity generation

Figure 4.92. Fit of the apparent, reversing specific heat capacity generated from Figure 4.91 with a single- and a double-exponential function (thin and thick curves, respectively). The range of relaxation times refers to the different annealing temperatures shown in Figure 4.89 and refers to data gained from standard DSC and MTDSC.

There is also a step-based equivalent technique founded on linear-response theory. This has been presented by Schick and co-workers [19] and is formally equivalent to the real and imaginary heat capacities generated by modulation at a single frequency. In principle, it is therefore possible to apply a Fourier transform to step-scan type data and break down the overall response into heat flow responses to a series of sinusoidal temperature modulations. 

Exampie A.3.1 The pressures for three steam mains have been set to the conditions given in Table A.l. Medium- and low-pressure steam are generated by expanding high-pressure steam through a steam turbine with an isentropic efficiency of 80 percent. The cost of fuel is 4.00 GJ and the cost of electricity is 0.07 h. Boiler feedwater is available at 100°C with a heat capacity... 

Phonon transport is the main conduction mechanism below 300°C. Compositional effects are significant because the mean free phonon path is limited by the random glass stmcture. Estimates of the mean free phonon path in vitreous siUca, made using elastic wave velocity, heat capacity, and thermal conductivity data, generate a value of 520 pm, which is on the order of the dimensions of the SiO tetrahedron (151). Radiative conduction mechanisms can be significant at higher temperatures. 

Calorimeter. The P-decay energy of tritium is very precisely known (9). The thermal energy generated by the decay can thus be used with a specially designed calorimeter to measure the quantity of tritium in a system of known heat capacity. 

R, = volume generation rate, ftVmin P = volumetric expansion coefficient, ftVlb-°F Q = heat input rate, Btu/min Cp = hquid heat capacity, Btu/lb-°F... 

A useful approximation to estimate the possibility of a particular reaction which depends on internal heat generation to produce the products in the proper state for separation is to ignore the heat losses from die reactor, and assumes an average heat capacity calculated from die Neumann-Kopp law... 

Heating capacity The capacity of a hear emitter, heat generator, or heat exchanger. 

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