Foreign-gas effect

The reactions referred to in Section A of this Part, O atom with 03 to give 02 and with 02 to give 03, were also considered. The foreign gas effects were attributed to their relative efficiencies as third bodies in the reaction between 0 atom and 02, as discussed in Part II. 

This agrees with the overall rate data, which is first order. However, estimates of the concentrations of the ethyl and hydrogen radicals, as found from the steady-state approximation and the free radical rate expressions, indicate that the former is the larger, and thus that the alternate termination reaction (f) would be more appropriate. Unfortunately, this is (jifi), and leads to an incorrect order of one-half. There are also other predictions of temperature coefficients of reaction and foreign gas effects that are not in agreement with the experiment. This is an illustration of how carefully one must cteck all the implications of an assumed mechanism. 

Tile role of this activated Hg-1 TO complex was further defined by the data of Xay et al. (28). Tmm a study of the liglh intensity dependence, quantum yield, and the effect of foreign gas molecules on the water reaction these authors proposed the following primary seouenee ... 

Interference from Noncondensable Gases. Foreign gas in the still comprises air from mechanical leaks and traces of dissolved gas that have survived the degasser. The effectiveness of the degasser was tested by measuring dissolved oxygen, according to the ASTM procedure which yielded the data of Table III. 

Effect of Foreign Gas on the Photo-Decomposition of Nitrogen Dioxide at 0°... 

Uniform Surface Temperature, Foreign Gas as Coolant. The effectiveness of air injection in reducing convective heat flux stimulated investigations into the use of other coolants With the introduction of a foreign species into the boundary layer, the boundary layer equations reduce to the continuity equation (Eq. 6.6), the momentum equation (Eq. 6.7), the energy equation... 

Uniform Surface Injection. Although a mass transfer distribution yielding a uniform surface temperature is most efficient, it is much easier to construct a porous surface with a uniform mass transfer distribution. Libby and Chen [34] have considered the effects of uniform foreign gas injection on the temperature distribution of a porous flat plate. For these conditions, however, boundary layer similarity does not hold. Libby and Chen extended the work of Iglisch [35] and Lew and Fanucci [36], where direct numerical solutions of the partial differential equations were employed. An example of the nonuniform surface enthalpy and coolant concentrations resulting from these calculations is shown in Fig. 6.16. 

The evaluation of the effectiveness of a transpiration cooling system utilizing a foreign gas is quite formidable and requires the use of complex computer codes. 

Early theories for transpiration of air into air [114, 115] were based on the Couette flow approximation. Reference 114 extended the Reynolds analogy to include mass transfer by defining a two-part boundary layer consisting of a laminar sublayer and a fully turbulent core. Here, t = 0 in the sublayer (y < y ), and t = OAy and (i = 0 in the fully turbulent region. The density was permitted to vary with temperature. The effect of foreign gas injection in a low-speed boundary layer was studied in Ref. 116, and all these theories were improved upon in Ref. 117. 

FIGURE 6.44 Compressibility effects on the reduction of the Stanton number by surface mass transfer on bodies with zero axial pressure gradient and including effects of foreign gas injection. 

The broadening of spectral lines can be due to Doppler effects, foreign gas, or resonance effects. Doppler broadening is due to the random motion of atoms. The atoms move in different directions and... 

L Galatry. Simultaneous effect of Doppler and foreign gas broadening on spectral lines. Phys Rev 122 1218-1223, 1961. 

Remark.- One could easily superimpose with this mechanism the effect of a foreign gas to the reaction or a catalytic effect of the water vapor in the same way as in the mechanism with gaseous diffusion. 

To be able to check guaranteed performance without the fouling effects caused by foreign material or impurities in actual duty gas. 

Thus, the preliminary chemisorption of a foreign donor gas causing a fall in e8 (at ev = const) must increase K (transfer from the point A to the point D in Fig. 9). The chemisorption of an acceptor gas accompanied by an increase in e8 (at tv = const) must weaken the effect (transfer from the point A to the point E). 

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