Flux rate conversion factors

Table 16.2 Flux-to-Dose-Rate Conversion Factors for Electrons and Betas ...

As with charged particles, tables have been developed that provide a flux-to-dose-rate conversion factor as a function of photon energy (Table 16.3 and Fig. 16.1). Using the conversion factor C( ), Eqs. 16.12 and 16.13 take the... 

Hollow fiber modules, or permeators, are precisely machined units containing bundles of hollow fine fibers positioned parallel to and around a perforated center feed-water tube, with only one or two bundles per pressure vessel. They are widely used for brackish and seawater applications. Hollow fiber modules exhibit a low flux rate (permeate flow per unit membrane per unit time) and can foul easily but tend to have high conversion factors (the percentage of feed flow converted to permeate), typically 50 to 55%. This makes them suitable for both small and large RO systems. They are easy to troubleshoot, and bundles are easy to change in the field. 

History Analysis of the 1030 El Monte Trajectory. Because of the relative completeness of initial conditions that we can relate to the Azusa station, we have chosen the 1030 trajectory to discuss in some detail. Examining Table VII, we note an overabundance of ozone at 1030 and a correspondingly rapid completion of NO NO2 conversion. Reactivity analyses (see Atmospheric Adaptation) and our early modeling studies suggest reduction of the oxidation rate constants. To achieve some level of comparative assessment with the previous work, we assign one-fourth the nominal NO flux and one-half the oxidation rate thus, f = 1/4 and r = 1/2 describe the conditions as before. This time, however, we preserve the HC/NOa,-ratio as in the entries in Table VII and reduce hydrocarbon fluxes by a factor of two. This means that the difference in end-point concentrations between this case and the 1/4< no, 1/2< hc entries results solely from the rate constant reduction. This differs from the earlier work where hydrocarbon fluxes were not reduced. 

Cells were grown in 15 ml test tubes under a photon flux density of approximately 150/iE/mVs and were aerated (2wm) with ordinary air containing 20 ppm CO2. Linear growth rate was converted to CO2 fibcation rate (gC02/l/ y) mdtiplying the conversion factor (1.65). The conversion factor is calculated as follows 44(CO2)/12(carbon)X0.45(carbon content of cells). 

Answer In both cases the dose rate is calculated by using Eq. 16.15 with a dose-to-flux conversion factor obtained from Table 16.3 for 0.662-MeV gammas. Using linear interpolation, that factor is 4.05 X 10 (Sv/s)/[y/(m s)]. 

The value of V just used can be the flux V", and to place the area on the basis of the feedstream rate F, the factor F"IV" = F/V) can then be introduced. As in Appendix 4, the conversion factor (divisor) to convert the arbitrary or dimensionless units into the prescribed area units of cm"... 

The performance or efficiency of a given membrane is determined by two parameters its selectivity and the flow through the membrane. The latter, often denoted as the flux or permeation rate, is defined as the volume flowing through the membrane per unit area and time. Although SI units are recommended, several other units are used in the literature to represent the flux. If the flux is considered to be a volume flux, the following units are used 1 nr hr, 1 m day, gal ft 2 day and cm cm 2 hr. The respective conversion factors are given in table 1.2. 

As been demonstrated by the graphs above, the fuel wood is significantly more difficult to thermochemically convert than wood pellets and wood chips, at a given volume flux of primary air and for the conversion concept studied. The relatively low conversion gas rates should be one of the most crucial factors in the explanation of... 

Negligible and medium interaction regimes. Experiments were carried out with an aqueous 2.0 M DIPA solution at 25 °C in a stirred-cell reactor (see ref. [1]) and a 0.010 m diameter wetted wall column (used only in negligible interaction regime, see ref. [4,5]). Gas and liquid were continuously fed to the reactors mass transfer rates were obtained from gas-phase analyses except for CO2 in the wetted wall column where due to low C02 gas-phase conversion, a liquid-phase analysis had to be used [5]. In the negligible interaction regime some 27 experiments were carried out in both reactors. The selectivity factors were calculated from the measured H2S and CO2 mole fluxes and are plotted versus k... 

The significance of this small effectiveness factor is the following The chemical reaction rate occurring inside the catalyst pores is much faster than the rate at which the reaction components can enter and then leave the catalyst pores. This means that the composition inside the pores can be at equilibrium the bulk gas composition is quite far from equilibrium. Therefore, when checking to see whether a reforming mixture has a tendency to form carbon, it is necessary to check the bulk composition of the gas as well as the equilibrium composition of the gas. As mentioned earlier, steam reformers can be said to be heat flux-limited, which means that the reactor is usually limited by heat transfer considerations and not by reaction kinetics. In other words, once the reformer has been configured in terms of the number of tubes and their dimensions to achieve the desired heat flux profile, there should be enough catalyst volume in the tubes to achieve the desired level of conversion. 

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