Energy balance potential expression

Equation 6-10 is the macroscopic energy balance equation, in which potential and kinetic energy terms are neglected. From tliermodynamics, the enthalpy per unit mass is expressed as... 

Since the reactor is adiabatic, 2 = 0 in the energy balance. If shaft work and kinetic and potential energy changes (VVs, A t, A p) are negligible compared to each of the first two terms in the expression for AW. the energy balance simplifies to AW = 0. which in turn leads to... 

Noting that energy can be transferred to or from a system by heal, work, and massjiow, and that the total energy of a simple compressible system consists of internal, kinetic, and potential energies, the energy balance for any system undergoing any process can be expressed as... 

For nonisothermal operations, we have to use the energy balance equation to express temperature variation along the reactor. Consider a section of volume V from the reactor inlet. Assuming negligible kinetic and potential energies, the energy balance equation is... 

In XPS one measures the kinetic energy of the photoelectrons emitted by the sample, kin- The electrical contact between the sample and the analyzer equalizes their electrical potential and, by this fact, their Fermi levels. It is therefore convenient to take the Fermi level as a reference point for the measurement. Thus, by arbitrarily setting Ep = 0, we can write an expression for the energy balance (Figure 3.16) ... 

Of the same order of magnitude as potential energy for liquids is the work exerted by (liquid) pumps imagine its expression in terms of total liquid head (equivalent height). Also power supply to pumps, though not perhaps negligible in the economic balance of the plant, is usually not detectable in the enthalpy (energy) balance set up around the units. 

From a practical point of view and to avoid bias in the ealeulation of NE for different feeds, it is necessary to carry out energy balance measurements in similar animals (i.e. same sex, same breed and in the same body-weight range), to keep these animals within their thermoneutral zone, to minimize variation in behaviour, and to feed the animals at about the same feed intake level with balanced diets so that the animals can express their growth potential. Under these circumstances, an erroneous estimate of FHP will affect the absolute NE value, but not the ranking between feeds. This also means that NE should not be measured in animals fed ingredients for which the chemical characteristics are very different from those of a complete balanced diet. 

MC-IR is expressed in the skin, and MC-2R in the adrenal gland. The MC-3 and MC-4 receptors are expressed in the brain and MC-5R in the brain and in peripheral tissues. The MC-4R receptor is involved in the regulation of food intake, energy balance, and body weight. Modulators of MC-4R were therefore considered to be potentially useful for the treatment of eating disorders (agonists to treat obesity, antagonists to treat anorexia). " ... 

Here one arrives at expressions which are equivalent to those in the initial macrocanonical approach but with the expression for the total energy replaced by the potential energy. One can now apply the principle of detailed balancing to these expressions. Thus, if the probability of the potential energy changing from (J, to U, is given by P j and the converse probability by /, then these expressions will be related by the equation... 

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