Energy conservation . See

NEMD simulations were started from well-equilibrated, independent, equilibrium configurations. The potential parameters e and a were chosen to be 480 K and 3.405 A, respectively. The simulations were performed at a reduced temperature of k T/e = 1 and at a density of po = 0.64. The equations of motion (Eqs. [202]) were integrated with the additional variable I with a time step of 0.5 fs to ensure an energy conservation (see Eq. [203]) of one part in 10 ... 

See Process energy conservation Separations process sttithesis. 

Simultaneous heat and mass transfer also occurs in drying processes, chemical reaction steps, evaporation, crystallisation, and distillation. In all of these operations transfer rates are usually fixed empirically. The process can be evaluated using either the heat- or mass-transfer equations. However, if the process mechanism is to be fully understood, both the heat and mass transfer must be described. Where that has been done, improvements in the engineering of the process usually result (see Process energy conservation). 

An important by-product of most energy technologies is heat. Few energy conversion processes are carried out without heat being rejected at some point in the process stream. Historically, it has been more convenient as weU as less cosdy to reject waste heat to the environment rather than to attempt significant recovery. The low temperatures of waste heat in relation to process requirements often make reuse impractical and disposal the only attractive alternative (see Process energy conservation). 

Variable drive fluid couplings (see Section 8.4.1(2)) These may not prove to be as effective from the point of view of energy conservation, as the motor will always be running at its rated speed and engagement of the coupling alone will vary the output speed. 

Static drives using solid-state technology (see Section 6.2) This is the best method for achieving the required speed variations, not from the point of view of quicker and smoother speed variations, but of total energy conservation even at low outputs. 

To see this quantitatively the first entropy is required. Let the energies of the respective reservoirs be ET . Imagine a fixed region of the subsystem adjacent to each boundary and denote the energy of these regions by Es . Now impose the energy conservation laws... 

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