HYDROGEN PARTIAL PRESSURE CALCULATIONS

Figure 6.6 shows the optical band gap of ITO films prepared at different hydrogen partial pressures. In the figure both direct and indirect optical band gaps of the films are calculated. Their maximum values of 4.21 and 3.35 eV are obtained for films prepared at the hydrogen partial pressure of 7.9 x 10-6 torr. The variation of both direct and indirect optical band gaps... 

FIGURE 6.6 Calculated direct and indirect optical band gaps of ITO films prepared at different hydrogen partial pressures. 

Table VII shows a comparison with experimental data by Leyko and Piatkiewicz (1 5) at 80 to 110 °C. At high temperatures partial pressures calculated from the BR- and EMNP-methods deviate by up to 20 per cent from the experimental results, whereas van Krevelen s method - extrapolated to 110 °C - yields partial pressures of hydrogen sulfide which are only about 1/4 to 1/5 of the measured values.

Zinc Chloride Hydrocracking—Batch Autoclave Work. All tests were made in a 316 stainless steel, 300-ml rocking autoclave. The equipment, the product work-up, analytical and calculational procedures used are all identical to those previously described (1). A constant hydrogen partial pressure was used in each run by monitoring it with a palladium-silver alloy probe within the authoclave. The sensitivity of the probe response was increased as compared with prior work by heat treating at... 

A I 000 hours run was used in this case, coresponding to 11 000 cm3 GO / cm3 catalyst The following experimental data were used in the kinetic calculation temperature, hydrogen partial pressure, LHSV, sulpher content of the feed and HGO, and the volume of GO which pass through the catalytic bed. 

For liquid yield, as well as for the other variables, the effects of temperature, hydrogen partial pressure and duration of the experiment have been calculated. 

As with oxygen ion-conducting electrolytes, proton conduction in these electrolytes occurs only within a limited range of hydrogen partial pressures. In addition, as they are oxides, oxygen defects can occur. Figure 13.6 shows the predominant defects in indium-doped calcium zirconate, which were calculated based on an extrapolation of conductivity measurements [79]. Hydrogen conduction occurs by interstitials H ... 

A generalized theoretical model based on the film theory was also developed for the calculation of the enhancement factor for the simultaneous absorption of two gases coupled with a complex reaction mechanism in liquid phase, in which the rate is negative-order with respect to one of the gases and first order with the other [40], This phenomenon is typically observed in hydroformylation reactions, where the reaction rate is first order with respect to hydrogen partial pressure and negative order with respect to CO. Practical implications of this analysis have been illustrated with the hydroformylation of 1-hexene. Thereby, an expression for the enhancement factor Eco has been derived, which is applicable irrespective of the regime of absorption. 

Table 8.8 presents these numbers in a slightly different way, in which the equilibrium constant is multiplied by the pressure term to whatever power is appropriate and the result is the ratio of naphthenes to aromatics, calculated for four temperatures—400°F, 600°F, 800°F, and 1000°F—at 2500 psi hydrogen partial pressure. High values of Keq pH2 correspond to low aromatic levels and are favored by low temperatures, hence the use of highly active noble metals and nickel catalysts for this purpose. Base metal sulfide catalysts have also been successfully used for this purpose, but are less likely to achieve very low product polyaromatic levels. 

Reaction Rate. We compared the integral methane formation rates from our pilot plant tests with those reported by others (1, 2, 6,14). To do so on the same basis, we took the reaction rate to be pseudo-first order with respect to the hydrogen partial pressure. The calculated reaction rate constant for each run is plotted against carbon gasification in Figure 5. Several observations can be made ... 

A copper storage tank containing dilute H2SO4 at pH = 0.1 is blanketed with hydrogen at 1 atm. Calculate the maximum Cu + contamination of the acid in moles Cu " per liter. What is the corresponding contamination if the hydrogen partial pressure is reduced to 10 atm ... 

Returning to the calculation of the hydrogen partial pressure, it is possible to write ... 

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