High-pressure ratio function

Using equation (9.13) and adding the limiting throat pressure ratio at sonic flow, we may define the high-pressure ratio function fhpr(P2/p, Cfgh) by ... 

Universal Gas Sizing Equation generalized mass-flow function kg/s fhpr high-pressure-ratio function ftpa long-pipe approximation flow function... 

The FUGSE blends the liquid-flow algorithm for high-pressure ratios with a choking equation valid at low valve pressure ratios by using a sine function, the argument of which is chosen to be proportional to the square root of the fractional pressure drop, =... 

The sum of the quantum yields of formation of the two ketones was found to be unity at both 366 and 253.7 nm thus quantum yields for the two ketones changed with pressure. The high-pressure ratio is that expected for thermal r-CsHnO radical decomposition. Thus from the shift in ratio as a function of temperature the fractions of excited radicals produced could be deduced (McMillan et al., 1971), and they are listed in Table 4. 

Available horsepower from a gas turbine is a function of air compressor pressure ratio, combustor temperature, air compressor and turbine efficiencies, ambient temperature, and barometric pressure. High ambient temperatures and/or low barometric pressure will reduce available horsepower while low ambient temperatures and/or high barometric pressure will increase available horsepower. All industrial turbines will have high-temperature protection, but in areas subject to very low ambient temperatures horsepower limiting may be required. 

N. E. Cohen, 13th Symp (Int) Combust (Proc) (1970), 1019—29 CA 76, 61471 (1972) To analyze and explain the mechanism of combustion of powdered metals in contact with a solid oxidizer (AP) with the powdered metal dispersed in solid AP (I), the combustion of various compressed I-Al and I-Mg mixts in N2 under various conditions in a high-pressure window bomb was studied. The regression-rate laws of the mixts at high and low pressures, the pressure limits for deflagration, and the structures of the combustion zone and of the surface were detd. The burning rate of various I-Al mixts, as a function of pressure, I particle size, and mixt ratio was determined by cinematography. The combustion was difficult to achieve... 

Carbon Monoxide. Carbon monoxide, a fuel in high-temperature cells (MCFC and SOFC), is preferentially absorbed on noble metal catalysts that are used in low-temperature cells (PAFC and PEFC) in proportion to the hydrogen-to-CO partial pressure ratio. A particular level of carbon monoxide yields a stable performance loss. The coverage percentage is a function of temperature, and that is the sole difference between PEFC and PAFC. PEFC cell limits are < 50 ppm into the anode major U.S. PAFC manufacturers set tolerant limits as < 1.0% into the anode MCFC cell limits for CO and H20 shift to H2 and C02 in the cell as the H2 is consumed by the cell reaction due to a favorable temperature level and catalyst. 

Figures 1 to 3 present calculated equilibrium molar ratios of products to reactants as a function of temperature and total pressure of 1 and 100 atm. for the gas-carbon reactions (4), (7), and (5), (6), (4), (7), respectively. Up to 100 atm. over the temperature range involved, the fugacity coefficients of the gases are close to 1 therefore, pressures can be calculated directly from the equilibrium constant. From Fig. 1, it is seen that at temperatures above 1200°K. and at atmospheric pressure, the conversion of carbon dioxide to carbon monoxide by the reaction C - - COj 2CO essentially is unrestricted by equilibrium considerations. At elevated pressures, the possible conversion markedly decreases hence, high pressure has little utility for this reaction, since increased reaction rate can easily be obtained by increasing reaction temperature. On the other hand, for the reaction C -t- 2H2 CH4, the production of methane is seriously limited at one atmosphere pressure and practical operating temperatures, as seen in Fig. 2. Obviously, this reaction must be conducted at elevated pressures to realize a satisfactory yield of methane. For the carbon-steam reaction.

Germanium surface passivation by chloride termination inhibits oxide formation and maintains a well-ordered surface. The chloride-terminated surface can also be used as a reactive precursor for wet organic functionalization. For example, Cullen et al. [105] first demonstrated the reaction of a chloride-terminated Ge(lll) surface with ethyl Grignard as a means of ethylation for use in surface stabilization. The chlorination was performed by a mixture of Cl2 and HC1 gas with N2 above atmospheric pressures [105]. Although this resulted in approximately a one-to-one ratio of adsorbed chlorine atoms with Ge surface atoms, the high pressures resulted in severe etching of the substrate [105]. 

The above studies support the notion that nucleation is a very stochastic phenomenon when the sample is held at constant temperature, compared to when the sample was cooled at a constant cooling rate. As suggested previously, the magnitude of the driving force can affect the degree of stochastic or random behavior of nucleation. For example, on the basis of extensive induction time measurements of gas hydrates, Natarajan (1993) reported that hydrate induction times are far more reproducible at high pressures (>3.5 MPa) than at lower pressures. Natarajan formulated empirical expressions showing that the induction time was a function of the supersaturation ratio. 

Theoretical approaches to total energy as a function of volume predict a phase transition to the rock salt structure under high pressure [11,12], The transition is calculated to occur at a pressure of about 245 GPa and an experimental value of 230 GPa [13] has been quoted [9], but other workers quote 10 -14 GPa [14]. The critical volume ratio [11] is V/V0 = 0.83, equivalent to a molecular volume reduction from 31 to 27 A3. 

According to the witnesses, the engines used to supply the gas chambers with gas were heavy Diesel engines taken from Soviet tanks, whose power ranged up to 550 hp. Since Diesel engines have a high compression ratio (1 15), it may be assumed that they are still able to function even if the pressure of the exhaust increases by 0.5 atm. after exiting the cylinder. 

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