Leakage factor

The leakage factor is the rate of air leakage at a given static pressure per m- of duct surface area ... 

The leakage factor depends on the pressure Ap,gf at which the leakage airflow rate is measured. In this case, it is the arithmetical mean value of the maximum and minimum values of the static pressure difference throughout the ductwork (Pa). 

TABLE 9.11 Maximum Leakage Factor for the Three Classes and for Typical Test Pressures... 

It might be thought as a consequence of measurements such as these that leakage factors are the main issues in fuel containment. However, although obviously important, in some cases a leak might occur only at intermittent intervals, and the associated problem might well be easily resolvable by component replacement. In contrast, the relevance of permeation to fluid containment is its continuous nature—its rate may be low, but it occurs all the time that fluid is contacting elastomer. Hence, this phenomenon is now considered in association with related processes absorption, adsorption, and diffusion. 

If the test has proceeded till a steady state (cone of depression fully developed), the leakage factor as well as the storage coefficient can be determined. These factors are less important but may be critical when it comes to modelling... 

Figure 6. The areal exhalation rate during the first 200 hours after closure, from the porous sample in Figure 2, with the leakage factor yas the variable parameter (yis defined in Figure 2) (theory).

In this simulation, a ligand/protein ratio of 10 1 was assumed. The kon rate was assumed to be 10 s The spectrometer frequency was set at 600 MHz. A somewhat longer correlation time of 10 s was assumed for the protein and the complex, primarily to ensure efficient spin diffusion. The ligand correlation time was fixed at 0.2966 ns, corresponding to null NOE at 600 MHz. A leakage factor of 0.3 s was assumed for all the protons in their free and bound states. This term was added to all the diagonal elements of the R matrix. 

Fig. 11 Comparison of experimental STDs (shaded circles) and calculated STD values (solid line) from CORCEMA-ST method for the crystal structure of chicken liver DHFR/TMP complex. The optimized parameters are tl =0.101 ns tp = 20.43 ns t i = 0.81 ps Tm2 = 3.04 ps Tm3 = 3.26 ps leakage factor = 0.065 and NOE R-factor = 0.076. Reprinted with permission from [75] 2005, American Chemical Society...

The leakage factor depends on radical concentration through T1. Assuming that the electron spin concentration is dilute relative to the nuclei, Equation (7) can be rewritten as... 

Since the leakage factor can be easily calculated from Ti relaxation data, and ys/y is constant, that only leaves the determination of smax before the coupling factor can be directly accessed. For solutions of radicals where Heisenberg exchange is prominent, Emax must be measured as a function of concentration and extrapolated to infinite concentration where smax 26,50 pQr jmmobilized or tethered radicals, nitrogen nuclear spin relaxation effectively mixes the hyperfine states in virtually all cases (small peptides may be an exception) and smax 1 can safely be assumed. 56 Alternately, the determination of smax can be avoided... 

Compute the quantity of flue gas handled. The quantity of gas reaching the induced draft fan is the sum of the actual air required for combustion from step 1, air leakage in the boiler and furnace, and the weight of fuel burned. With an air leakage of 10 percent in the boiler and furnace (this is a typical leakage factor applied in practice), the gas flow is as follows ... 

Since Wq + 2Wi + W2) represents that part of the nuclear relaxation rate that arises from interaction with the electrons, and Wj represents contributions to the nuclear relaxation rate from other interactions, such as are normally present in diamagnetic systems (and usually written as l/T o). the leakage factor /may then be written as... 

Thus/measures the fraction of the total relaxation rate due to nuclear-electron interactions when nuclear—electron interactions are negligible, /=0, and when they are dominant/= 1. With these definitions for the coupling parameter p and leakage factor / equation (10) be-... 

A is the fraction of neutrons which are not lost through leakage to the surroundings the non-leakage factor). In order to minimize the neutron leakage, the reactor core is surrounded with a neutron reflector which for thermal neutrons in LWRs is water (graphite or beryllium are sometimes used in other reactor designs) for fast neutron reflection iron is frequently used. 

All practical reactors have some leakage of neutrons out of the reactor core. This leakage A is approximately described by the fast and thermal leakage factors Af and A,j, respectively ... 

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