Capacity weighted average

Shelf area, m Floor s ace, m Weight average, kg Pump capacity, mVs Pump motor, kW Condenser area, m Price/m (1995) ... 

In Table IV the heats of formation of several nitroaromatic compounds in the ideal gas state are calculated from the measured heats of formation of the solid and the measured heats of sublimation. In cases where the heat of sublimation is not measured at 298°K there should be a correction for the differences in heat capacities of the solid and ideal gas. The data required to make these corrections are not available but in general it is expected that the corrections will be small and can be neglected. From the heats of formation of each compound in the ideal gas state, a value for the group Cb-N02 (ideal gas) has been derived (Table IV). A weighted-average value (CB-N02(ideal gas)) = 3.0 kcal/mole was used, and a heat of formation was estimated for each compound. In Table IV the difference between observed and estimated heat of formation in the ideal gas state is less than + 3.2 kcal/mole in all cases... 

To a first approximation, the heat capacity in these heterogeneous, multiphase systems, Cp can be approximated by a weighted average of the component heat capacities ... 

In order to understand and correlate the heat transfer data, the relevant physical properties of the suspensions must be carefully evaluated. The experimental determination of heat capacity and density pose no particular problem. In many instances it is possible to estimate these values accurately by assuming them to be weight averages of those of the two components. In contrast, great difficulty is associated with the accurate determination of thermal conductivity and viscosity, largely owing to the fact that the solids tend to settle readily in any device where convection currents are eliminated, as they must be for these... 

The above calculation indicates that the vapour flow rate is 2.63 kg/s and the gas flow rate is 0.4536 kg/s. This can be used to obtain weighted average values of physical properties required for calculating the relief system capacity. 

Equation (3.5-18) has been written in terms of molar heat capacities Cpm(i), rather than heat capacities of formation, because the heat capacities of the elements are on both sides and cancel. The second term of this equation is always positive because the weighted average of the squares is always greater than the square of the average. Equation 3.5-18 is in accord with LeChatelier s principle As the temperature is raised, the equilibrium shifts in the direction that causes the absorption of heat. Equation 3.5-18 can also be derived using CP = — T(d2G/dT2)P (equation 2.5-25). 

Fig. 7 Temperature dependence of partial heat capacity (Cp) of two pairs of NIPAM-co-VP copolymers in water. The weight average molar masses of NIPAM-co-VP/60/5, NIPAM-co-VP/30/5, NIPAM-co-VP/60/10 and NIPAM-co-VP/30/10 are 2.9 x 106, 4.2 x 106, 5.6 x 106 and 7.9 x 106 g/mol, respectively. The polymer concentration is 10-3 g/mL. The temperature was increased with a rate of 1.5 °C/min and pressure was maintained at 180 kPa [56]...

If the quantity of adsorbent should be increased by the addition of more material in the same state of subdivision, we could measure changes in volume, in heat capacity, and in certain other extensive properties which can be directly observed. We could differentiate any one of these properties with respect to the number of moles of adsorbent (whether the system contains one, two, or more components) to obtain a partial molal property. The partial molal property so obtained would be the weighted average for interior and exterior adsorbent and is in harmony with Equations 9 and 11. 

Equation 10.12 is more informative than the equivalent Equation 3.21 for interpreting the influence of temperature under IPC conditions. Equation 10.12 indicates that the experimental capacity factor is actually the weighted average of the electrostatically modulated retention factors of the free analyte and that of the paired analyte. Notably, the global A7/° for IPC retention can be thought of as a weighted average of the retention of both free (electrostatically tuned) analyte and paired analyte. 

Thus the transformed heat capacity of a species can be positive or negative. The transformed heat capacity of a reactant involving two or more species is not simply a weighted average, but is given by the following equation. 

The second term in this equation is always positive because the weighted average of the squares of the individual standard transforme enthalpies of formation of the species is always greater that the square of the weighted average enthalpy of formation (6). This is the quantitative expression of Le Chatelier s principle for the heat capacity. 

The entropy of CuCl was obtained from the several pieces of equilibrium data reported above and the adopted A.H (298J.5 K). A -1 -1 weighted average of 20.8 1 cal K mol was adopted for S CCuCl, cr, 298.15 K). The enthalpy and heat capacity above 298.15 K have... 

Our adopted value is based on a weighted average of all the data. Heat Capacity and Entropy... 

For ideal gas mixtures, the heat capacity (per mole) of the mixture is the mole weighted average of the heat capacities of the components ... 

Comparison of the urinary trichloro-compound levels with tetrachloroethylene in the environment revealed that while the metabolite levels increased essentially parallel to PERC concentrations up to 100 ppm, leveling off was apparent in the metabolite excretion when the exposure to PERC was more intense (e.g., more than 100 ppm), indicating that the capacity of humans to metabolize this chlorinated hydrocarbon is rather limited. A tentative calculation indicated that at the end of an 8 h shift with exposure to tetrachloroethylene at 50 ppm (time-weighted average, TWA), 38% of the PERC absorbed through the lung would be exhaled unchanged, <2% would be metabolized to be excreted in the urine, while the rest would remain mostly in the fat stores of the body to be eliminated later. 

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