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Balance difference

Modification of inertia of hydrogen-only rigid bodies is a simple and safe way to balance different frequencies in the system, and it usually allows one to raise to 10 fs. Unfortunately, the further increase appears problematic because of various anharmonic effects produced by collisions between non-hydrogen atoms [48]. [Pg.128]

Energy balances differ from mass balances in that the total mass is known but the total energy of a component is difficult to express. Consequently, the heat energy of a material is usually expressed relative to its standard state at a given temperature. For example, the heat content, or enthalpy, of steam is expressed relative to liquid water at 273 K (0°C) at a pressure equal to its own vapor pressure. [Pg.364]

Energy balances differ from mass balances in that the total mass is known but the... [Pg.365]

Material and Energy Balances in the Design of Industrial Reactors. The analysis of chemical reactors in terms of material and energy balances differs from the analysis of other process equipment in that one must take into account the rate at which molecular species are converted from one chemical form to another and the rate at which energy is transformed by the process. When combined with material and... [Pg.252]

Note that the ExQ1 and ExQ2 terms differ for the reversible and irreversible cases. The reversible case has the minimum heat input Qmm at temperature level Tb since heat is transferred reversibly without a temperature gradient. Similarly, it is rejected at Tt. It is in these two terms that the reversible and irreversible exergy balances differ. Now, first consider the reversible exergy balance, where Exlost is, by definition, equal to zero. From Equation 10.19, for the reversible case, we obtain... [Pg.156]

However because the rate law expressions for iron sulfide formation (equations 8 and lO) are non-linear the differential equations for H2S and the iron sulfides are not amenable to explicit solution Thus it is important to develop an equation for that can be incorporated in a numerical solution technique such as that of Runge-Kutta (15) Fortunately an appiropriate differential equation for can be developed firom charge balance considerations Here it is assumed that dissolved substances other than those listed in Table I are not affected by diagenesis If this is true, then a charge balance difference equation can be written (16) ... [Pg.804]

Removal of free ions occurs by two mechanisms ion-ion recombination (essentially saturated ternary ion-ion recombination effective binary coefficient a = 2 10 cm s ) and ion-attachment to aerosol particles. The latter process leads to so-called large ions which are, in fact, electrically-charged aerosols rather than ions in a strictly physical sense [60]. Usually, ion-attachment is the most important sink for free ions throughout the troposphere as the tropospheric aerosol content is relatively large (Fig. 2). In this respect, the tropospheric ionization-deionization balance differs greatly from the stratospheric one. [Pg.122]

All benefits information must be fairly balanced with risk information. The FDA defines fair balance as a balanced presentation of benefits and risks. This means that, in an advertisement, for example, to the extent that a particular benefit is described, the medical risks associated with that benefit also must be described. Fair balance also may mean that a product s limitations must be delineated. Fair balance differs for each individual drug and commrmication technique. The FDA requires that the presentation of all side effects and contraindications must have a prominence and readability that is reasonable, comparable to the presentation of benefits information. [Pg.59]

Our restriction to simple fluids was meant to emphasize general laws and phenomena. For this reason, we did not discuss theories of the surface tension of solids, for which a variety of models have been elaborated. One of the considerations for omitting these was that such tensions cannot be measured, so that a check of the quality is edso impossible. We also consciously excluded the surface tensions of liquid metals, liquid crystals, molten crystals and polymer melts. However, spread and adsorbed polymer layers will be considered in chapter 3 and 4, respectively. For similar reasons, and because most practical applications involve ambient temperatures, we did not extensively discuss critical phenomena, notwithstanding their Intrinsic Interest. Under critical conditions the surface energy - surface entropy balance differs considerably from that at lower temperatures, emphasized in this chapter. [Pg.199]

Figure 28-9 When two atoms i and j are separated by infinite distance, there are no interactions between them. As two nonbonded atoms approach one another, two forces have to be considered. Attractive dispersion forces (London forces) result from the interaction of instantaneous dipoles on each atom i and j. As the nonbonded atoms continue to approach one another, a repulsive interaction overwhelms the attractive interaction. and the energy curve rises sharply. The two nonbonded atoms can reach an equilibrium position where repulsive and attractive forces balance. Different mathematical relationships have been used in force field calculations to reproduce the nonbonded steric interactions. Figure 28-9 When two atoms i and j are separated by infinite distance, there are no interactions between them. As two nonbonded atoms approach one another, two forces have to be considered. Attractive dispersion forces (London forces) result from the interaction of instantaneous dipoles on each atom i and j. As the nonbonded atoms continue to approach one another, a repulsive interaction overwhelms the attractive interaction. and the energy curve rises sharply. The two nonbonded atoms can reach an equilibrium position where repulsive and attractive forces balance. Different mathematical relationships have been used in force field calculations to reproduce the nonbonded steric interactions.
This approach makes the velocities in the population balance different from the mass- or phase weighted average velocities obtained solving the two-fluid model. This discrepancy is an argument for the formulation of a mass density population balance instead of a number balance to achieve a consistently integrated population balance within the two-fluid modeling framework. [Pg.839]

Because the masses were measured on balances differing in accuracy, the least accurate measurement limits the number of digits past the decimal point. [Pg.796]

Since the reactor is adiabatic and no heat is transferred to the surroundings then UAf/dl T- Tg) >0 anjd the energy balance differ-... [Pg.449]

Any evaluation should consider not only the assay but the levels of degradation products and appropriate attributes. Where appropriate, attention should be paid to reviewing the adequacy of the mass balance, different stability and degradation performance. [Pg.212]

The analysis of chemical reactors in terms of material and energy balances differs from the analysis of other process equipment in that one must take into account the rate at which molecular species are converted from one chemical form to another and the rate at which energy is transformed by the process. When combined with material and energy balances on the reactor, the reaction rate expression provides a means of determining the production rate and the composition of the product stream as functions of time. Both steady-state and time-varying situations may be analyzed using the same fundamental relations. Differences in the analyses result from the retention of different terms in the basic balance equations. A material balance on a reactant species of interest for an element of volume AV can be... [Pg.222]

Mass balances for the system shown in Figure 8-6 are of interest. The external mass balances are identical to Eqs. (8z3a) and (8z3b). Thus, the bottoms flow rates are given by Eqs. (8-4) and 18-5T Although the processes shown in Figures 8-4A and 8zS are very different, they look the same to the external mass balances. Differences in the processes become evident when balances are written for individual columns. For instance, for column 2 in Figure 8-6 the mass balances are... [Pg.308]

In the following sections it is not so much the author s intention to balance different scientific tools against each other, but rather to propose some criteria for the judgement of a reliable peptide synthesizer. [Pg.72]

Under balance inconsistency we understand the measure of how the balance equations are not satisfied with the measured data. In case of singlecomponent balances, frequently used is the notion of balance difference (balance deficit), which is the difference between input and output flows. A balance difference can be due both to a mistake in the balance scheme and to gross error of measurement. [Pg.467]

As already said, the balance difference r is defined by the relation... [Pg.467]

Having evaluated the balance differences, one has to answer the basic question ... [Pg.467]

Is the balance difference due to random measurement errors only (in the range of maximum measurement errors), or is there a gross error present ... [Pg.468]

The balance difference is compared with a critical value. If... [Pg.468]


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See also in sourсe #XX -- [ Pg.467 ]




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