Penetration factor

The effect of the disturbance of the supply airflow on the plumes is presented in Fig. 8.39. The heat removal effectiveness j and contaminant removal effectiveness are presented as functions of the penetration factor P of the plume, which is the ratio of penetrated plume airflow rate to the whole plume airflow rate. The total heat load is 60 W m"- and the power of one hear source is 500 W. The supply airflow rate is 8 L S m -. 

The skin exposure is first calculated by correcting the outer whole-body dosimeter residues by the penetration factor. The penetration factor is derived from dividing the total outer torso residues into the total residues on the combined tee-shirt and brief... 

In order to determine the dermal exposure of volunteers to chlorpyrifos, the penetration of chlorpyrifos through the outer whole-body dosimeter (coveralls) to the inner body dosimeter (t-shirt and briefs) was measured. The penetration factor was calculated for each volunteer in the study from the experimental data by dividing the amount of chlorpyrifos on the t-shirt and brief sample by the amount of chlorpyrifos on the torso section of the coveralls. This method of calculation assumes that the surface area of the torso section of the coveralls is nearly the same as the surface area of the t-shirt and briefs worn directly under the torso section of the coveralls. A mean penetration factor for each worker type was calculated by averaging all the worker volunteer... 

Worker type No. replicates Location Mean penetration factor... 

Laboratory analytical recoveries and field spike recoveries were acceptable for all substrates encountered in this series of studies. Calculated penetration factors were similar to penetration factors reported in the literature. 

A more exact expression for the barrier penetration factor, derived for example by Clayton (1968), is... 

For slow neutron-induced reactions that do not involve resonances, we know (Chapter 10) that ct ( ) °c 1 /vn so that (ctv) is a constant. For charged particle reactions, one must overcome the repulsive Coulomb force between the positively charged nuclei. For the simplest reaction, p + p, the Coulomb barrier is 550 keV. But, in a typical star such as the sun, kT is 1.3 keV, that is, the nuclear reactions that occur are subbarrier, and the resulting reactions are the result of barrier penetration. (At a proton-proton center-of-mass energy of 1 keV, the barrier penetration probability is 2 x 10-10). At these extreme subbarrier energies, the barrier penetration factor can be approximated as ... 

Finally studies have reported the penetration factor which describes penetration and not decay. Penetration factors are not directly observable and they are usually calculated from infiltration rates and decay rates [11],... 

Chen C, Zhao B (2011) Review of relationship between indoor and outdoor particles I/O ratio, infiltration factor and penetration factor. Atmos Environ 45(2) 275-288... 

According to the Darcy law in laminar flow of homogeneous liquids via a porous medium with the penetration factor Kp, the process of a liquid... 

In general case, the penetration factor Kp changes with time as along with the liquid flow in the uninfiltrated part of a diamond compact, the sintering of diamond particles takes place. 

Transfer coefficient data could be subsetted from a re-entry database based on the anticipated label-specified clothing, or the appropriate TC data for specific body areas could be adjusted by a generic clothing penetration factor (see... 

Of the effective compodnds available at the present time, the )3-lactam antibiotics, the aminoglycosides and the polymyxins are all bacteriocidal. The j8-lactam antibiotics, notably carbenicillin, suffer primarily from the penetration factor but enzyme activity can play an important part. The aminoglycosides, on the other hand, have few or no penetration problems but are subject to enzymatic modification. The polymyxins penetrate to the active site and appear to be resistant to enzymatic modification. However, toxicity problems associated with polymyxin therapy prevent the widespread use of these drugs. 

Froman writes the solution in terms of two phase shifts, which we call A and 8, for the inner and outer wells respectively, and a penetration factor 7 representing the barrier between them. The inner well extends from r to T2, the barrier from r2 to rz, and the outer well from rz to r4. Thus... 

J. Humblet, Theory of nuclear reactions IV. Goulomb interactions in the channels and penetration factors, Nucl. Phys. 50 (1964) 1. 

Regions protected by coveralls have also been adjusted by a clothing penetration factor of 3.4. 

For Workers 1 and 2 the penetration factor has been applied to the chest but not to the neck which remained unprotected. 

Here B is the penetration factor of the membrane with respect to the dissolved substance, is the dissolved substance concentration in the solution in front of the membrane (it is assumed that behind the membrane, C i C ), Rs is the hindrance factor of the membrane. According to (6.57), osmotic pressure of infinite diluted solutions is proportional to the concentration of dissolved substance. So, we can use formulas (6.57) and (6.58) to estimate the rate of solution filtration through the membrane [4] ... 

Penetration of potential barriers. In all types of nuclear reaction the incident particle must pass through, or into, a region of varying potential V(r) before the reaction can take place. In general, the wave function of the incident particle is modified by the field, and the amplitude of this function at the nucleus differs from its asymptotic value. This leads to a penetrability factor in the reaction cross section. In addition, the incident particle having penetrated the external barrier suffers a change of wave number inside the nucleus and this in itself leads to some reflection at the nuclear surface. These factors are discussed in full in [7], p. 358, and only the main results are summarised here. 

Gamow(1928) and independently Condon and Gurney(1928,1929) have shown that such a penetration of an a particle through the potential harrier is possible in quantum mechanics. The mechanism is called tunneling. One can define a penetration factor (penetrability) P, which is the ratio of emergent and incident intensities. A detailed quantum-mechanical approximate theory gives the following expression for the penetration factor ... 

Therefore, in the Schrodinger equation (O Eq. (2.65)) the VdouL. = 2Ze /r term must be replaced hj V = Vcoul. + VdENTRiE- According to the calculations of Winslow and Simpson (1954) the effect of the orbital angular momentum (i), taken away by the a particle, on the penetration factor is as follows (O Table 2.8) ... 

Penetration factor for different values of the orbital angular momentum (/) taken away by the a... 

In his classical works Mang (1960,1964) developed an a-decay model in a fairly general form. According to his theory, the a-decay probability X depends on the penetration factor Pjand the so-called reduced a width in the following way ... 

If the barrier is robust, as it is for HI fusion, Wentzel-Kramers-Brillouin (WKB) logic can be used to generate the transmission coefficient (Gamow penetration factor) as a function of the energy of relative motion s (as it is for spontaneous alpha-decay). 

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