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Dominant distribution

What is the meaning of these peaked dwell time distributions Mathematically, the dwell time distribution is the convolution of the individual exponential distributions governing the underling state lifetimes [79]. If one of these lifetimes is much longer than the others, we would expect to see a distribution dominated by a single exponential decay. However, if multiple kinetic states have lifetimes of comparable duration, these states can be thought of... [Pg.253]

Preoxidation of the coal generates in low activated chars a microporous structure characterized by a narrow size distribution (domination of micropores accessible for benzene but inaccessible for cyclohexane, i.e., with widths between 0.41 and 0.54 nm). The molecular sieve properties of these chars are however not accompanied by sufficiently high pore volumes within the indicated pore widths region. Figures 6 and 7... [Pg.661]

Specifically = l/vH should be proportional to 3m. Further, if the particle distribution dominates the noise spectrum, the slope of /w(v) at i amplitude should correlate with the particle distribution spread as represented by o . The slope, designated as In o, of the form y... [Pg.277]

We will consider only the influence of activation overpotential or overvoltage on secondary current distribution. It is useful to regard the slope of the polarization curve dE /di (if any effect of concentration overpotential can be ignored) as a polarization resistance R. This represents the slowness of charge transfer across the interface and is based on the electrode kinetics of the reaction. If acts in series with R, the resistance of the electrolyte, we can distinguish between two situations. If R R, then the kinetics of charge transfer and not electrolyte resistance determine the current distribution, i.e., secondary current distribution dominates. Conversely, if R R, primary current distribution dominates. Secondary current distributions tend to smooth out the severe nonlinear variations of current associated with primary distributions and they eliminate infinite currents associated with electrode edges. [Pg.213]

Beryllium-7 aerosol measurements carried out by Papastefanou and loannidou (1995) at sea level in a coastal area, in a hilly area, at 250 m height and on the top of a mountain, at 1000 m altitude, showed that the Be activity size distribution dominated a smaller size range of aerosol particles with an AMAD of 0.68 pm (ag = 2.18) at a height of 250 m and an AMAD of 0.68 pm (ag = 2.24) at a height of 1000 m, showing a dependency on altitude. In marine environments at sea-level, the " Be activity size distribution dominated a higher size range of aerosol particles with an AMAD of 0.82 pm (ag = 1.88). [Pg.13]

Warning the candidate distritadion must dominate the target It is very important that the independent candidate distribution dominate the target. That means it must have heavier tails than the taiget. The acceptance probability for the... [Pg.164]

It is important to recognize the approximations made here the electric field is supposed to be sulficiently small so that the equilibrium distribution of velocities of the ions is essentially undisturbed. We are also assuming that the we can use the relaxation approximation, and that the relaxation time r is independent of the ionic concentration and velocity. We shall see below that these approximations break down at higher ionic concentrations a primary reason for this is that ion-ion interactions begin to affect both x and F, as we shall see in more detail below. However, in very dilute solutions, the ion scattering will be dominated by solvent molecules, and in this limiting region A2.4.31 will be an adequate description. [Pg.571]

Detennining the contact area between two rough surfaces is much more difficult than the sphere-on-flat problem and depends upon the moriDhology of the surfaces [9]. One can show, for instance, that for certain distributions of asperity heights the contact can be completely elastic. However, for realistic moriDhologies and macroscopic nonnal forces, the contact region includes areas of both plastic and elastic contact with plastic contact dominating. [Pg.2742]

Therefore, the absorjDtion line is massively inlromogeneously broadened at low temperature. An inliomogeneous lineshape can be used to detennine the static or quasistatic frequency spread of oscillators due to a distribution of environments, but it provides no dynamical infonnation whatsoever [94, 95]. As T is increased to 300 K, the absorjDtion linewidth decreases and increases. At 300 K, the lineshape is nearly homogeneously broadened and dominated by vibrational dephasing, because fast dephasing wipes out effects of inliomogeneous environments, a well known phenomenon tenned motional narrowing [951. [Pg.3045]

The alkali metals tend to ionize thus, their modeling is dominated by electrostatic interactions. They can be described well by ah initio calculations, provided that diffuse, polarized basis sets are used. This allows the calculation to describe the very polarizable electron density distribution. Core potentials are used for ah initio calculations on the heavier elements. [Pg.286]

In a typical amorphous adsorbent the distribution of pore size may be very wide, spanning the range from a few nanometers to perhaps one micrometer. Siace different phenomena dominate the adsorptive behavior ia different pore size ranges, lUPAC has suggested the foUowiag classification ... [Pg.254]

As illustrated ia Figure 6, a porous adsorbent ia contact with a fluid phase offers at least two and often three distinct resistances to mass transfer external film resistance and iatraparticle diffusional resistance. When the pore size distribution has a well-defined bimodal form, the latter may be divided iato macropore and micropore diffusional resistances. Depending on the particular system and the conditions, any one of these resistances maybe dominant or the overall rate of mass transfer may be determined by the combiaed effects of more than one resistance. [Pg.257]

Chemical composition data for CPM and FPM for a variety of locations are summarized in Table 5. These data illustrate several important points. First, the distributions of the PM q between CPM and FPM vary from about 0.4 to 0.7. Second, the ratio of PM q to TSP varies from 0.58 to 0.79. In general, both this ratio and the ratio of FPM to PM q tend to be higher at mral sites, but Bermuda, because of the large influence of sea salt in the CPM, is an exception. Sulfate (SO ), carbon (as organic carbon, OC, and elemental carbon, EC), and nitrate (NO3 ) compounds generally account for 70—80% of the FPM. In the eastern United States, compounds are the dominant species, although very Httie is emitted directiy into the atmosphere. Thus... [Pg.374]

Theoretical studies of diffusion aim to predict the distribution profile of an exposed substrate given the known process parameters of concentration, temperature, crystal orientation, dopant properties, etc. On an atomic level, diffusion of a dopant in a siUcon crystal is caused by the movement of the introduced element that is allowed by the available vacancies or defects in the crystal. Both host atoms and impurity atoms can enter vacancies. Movement of a host atom from one lattice site to a vacancy is called self-diffusion. The same movement by a dopant is called impurity diffusion. If an atom does not form a covalent bond with siUcon, the atom can occupy in interstitial site and then subsequently displace a lattice-site atom. This latter movement is beheved to be the dominant mechanism for diffusion of the common dopant atoms, P, B, As, and Sb (26). [Pg.349]


See other pages where Dominant distribution is mentioned: [Pg.149]    [Pg.523]    [Pg.202]    [Pg.35]    [Pg.241]    [Pg.107]    [Pg.13]    [Pg.2472]    [Pg.44]    [Pg.48]    [Pg.452]    [Pg.409]    [Pg.876]    [Pg.384]    [Pg.149]    [Pg.523]    [Pg.202]    [Pg.35]    [Pg.241]    [Pg.107]    [Pg.13]    [Pg.2472]    [Pg.44]    [Pg.48]    [Pg.452]    [Pg.409]    [Pg.876]    [Pg.384]    [Pg.85]    [Pg.835]    [Pg.902]    [Pg.1071]    [Pg.2082]    [Pg.2931]    [Pg.485]    [Pg.400]    [Pg.597]    [Pg.142]    [Pg.15]    [Pg.79]    [Pg.337]    [Pg.52]    [Pg.161]    [Pg.377]    [Pg.418]    [Pg.429]    [Pg.544]    [Pg.390]    [Pg.400]    [Pg.132]    [Pg.287]   
See also in sourсe #XX -- [ Pg.116 , Pg.119 ]




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