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Profile exponential

Table 2, column 2. shows that the median time delay does not vary significantly between transmissivity fields. This is explained by the fact that the mean transmissivity profile (exponentially decaying over depth) has been calibrated, prior to the introduction of any random variation, to achieve the observed 4.5 month delay for cluster a at 2 km depth. [Pg.621]

As evident from Fig. XI-6, the mean field produces concentration profiles that decay exponentially with distance from the surface [66]. A useful approximate solution to Eq. XI-18 captures the exponential character of the loop concentration profile [67], Here a chain of length iV at a bulk concentration of (j>b has a loop profile that can be estimated by... [Pg.401]

The quantitative analysis of the scattering profile in the high q range can be made by using the approach of Debye et aJ as in equation (B 1.9.52). As we assume tiiat the correlation fiinction y(r) has a simple exponential fomi y(r) = exp(-r/a ), where is the correlation length), the scattered intensity can be expressed as... [Pg.1415]

In an ideal continuously stirred tank reaclor (CSTR), the conditions are uniform throughout and the condition of the effluent is the same as the condition in the tank. When a batteiy of such vessels is employed in series, the concentration profile is step-shaped if the abscissa is the total residence time or the stage number. The residence time of individual molecules varies exponentially from zero to infinity, as illustrated in Fig. 7-2>e. [Pg.695]

The graphs of each of the species concentrations are plotted as a function of position along the tube z and time t. At the edges of the graphs for the concentrations of A and B we see the boundary and initial conditions. All values are unit or zero concentration as we had specified. As we move through time, we see the concentrations of both species drop monotonically at any position. Furthermore, if we take anytime slice, we see that the concentrations of reactants drop exponentially with position—as we know they should. At the longer times the profiles of... [Pg.456]

A crucial element in MTR is the profile of the localized state density as a function of eneigy, the so-called density of states (DOS). Unfortunately, a direct derivation of the DOS from the variation of the mobility is not straightforward. In two papers published in 1972 and 1976 [116, 117], Spear and Le Comber developed a method based on a simplified description of the accumulation layer, which was assumed to behave like a depletion (Schottky) layer, with a constant density of carrier up to a given thickness L This method has been more recently analyzed by Powell [118], who concluded that is was only able to give a rough estimate of the DOS. Nevertheless, we have used this method to estimate the DOS in 6T and DH6T [115] and found an exponential distribution of the form... [Pg.264]

At steady-state condition the oxygen concentration profile would be an exponential model ... [Pg.45]

Fig. 9. Comparison of the analytical SCF model [56] with the full numerical SCF calculation [53] for the segment density profile in flat, grafted layers at various surface densities (o is the fraction of the maximum possible surface coverage of grafted ends). The analytical profile is parabolic to its tip, while the numerical calculation shows that the density at the periphery of the layer drops off exponentially... Fig. 9. Comparison of the analytical SCF model [56] with the full numerical SCF calculation [53] for the segment density profile in flat, grafted layers at various surface densities (o is the fraction of the maximum possible surface coverage of grafted ends). The analytical profile is parabolic to its tip, while the numerical calculation shows that the density at the periphery of the layer drops off exponentially...
The concentration-time profile for this system was calculated for a particular set of constants k = 1.00X 10 6 s k = 2.00X 10 4 molL 1,and [A]0 = 1.00xl0 3M. The concentration-time profile, obtained by the numerical integration technique explained in Section 5.6, is shown in Fig. 2-11. Consistent with the model, the variation of [A] is nearly linear (i.e., zeroth-order) in the early stages and exponential near the end. [Pg.35]

Figure 21.23 exhibits the room-temperature fluorescence decay profiles of Ba3BP30i2 Eu powders. The experimental decay curve can be fitted by an equation with two exponential terms corresponding to two decay times of 20 ns (98.97%) and 522 ns (1.03%), respectively. [Pg.320]

The consequence of moving consciously toward this model will be the provision of a robust and scalable IT infrastructure and systems able to cope with exponentially growing data mountains that will need to be integrated and shared, accessed and mined in the most effective way. It will also require formidable computing power and sophisticated algorithms to be able to simulate both organs and whole body systems to reduce expensive failures in the clinic and predict much earlier the pharmacokinetic and pharmacodynamic properties and toxicological and efficacy profiles of molecules in pharmaceu-... [Pg.754]

FIGURE 4.2.3 UV-vis spectral changes and AAbs obtained by heating bixin in water ethanol (8 2) at 92°C. Inset shows kinetic profile at several wavelengths, with the solid lines representing the fitting of experimental data from the sum of two exponential functions. From Rios, A.O., Borsarelli, C.D., and Mercadante, A.Z., J. Agric. Food Chem., 53, 2307, 2005. With permission. [Pg.228]

Figure 4.6 shows an apparatus for the fluorescence depolarization measurement. The linearly polarized excitation pulse from a mode-locked Ti-Sapphire laser illuminated a polymer brush sample through a microscope objective. The fluorescence from a specimen was collected by the same objective and input to a polarizing beam splitter to detect 7 and I by photomultipliers (PMTs). The photon signal from the PMT was fed to a time-correlated single photon counting electronics to obtain the time profiles of 7 and I simultaneously. The experimental data of the fluorescence anisotropy was fitted to a double exponential function. [Pg.62]

Figure 5.11 shotvs the temporal profile of the intensity change in the SFG signal at the peak of the Vco mode (2055 cm ) at OmV induced by visible pump pulse irradiation. The solid line is the least-squares fit using a convolution of a Gaussian function for the laser profile (FWFJ M = 20 ps) and a single exponential function for the recovery profile. The SFG signal fell to a minimum within about 100 ps and recovered... [Pg.86]

Figure 6. An example of the use of to assess the growth rate of Mn nodules taken from Krishnaswami et al. (1982). Both panels show the same °Thxs data from nodule RN Vitiaz from the Southern Indian Oeean. Errors on the activities are within symbol size. The lower panel shows the hxs activity, while the upper panel shows the same data normalized to the Th activity. Note that both profiles show a general exponential decrease which can be used to assess the growth rate using the relationship that °Thxs ° = 230j jj imtiai g-X23ot showu ou both panels are for a steady growth rate of 1.15 mmMyr. Figure 6. An example of the use of to assess the growth rate of Mn nodules taken from Krishnaswami et al. (1982). Both panels show the same °Thxs data from nodule RN Vitiaz from the Southern Indian Oeean. Errors on the activities are within symbol size. The lower panel shows the hxs activity, while the upper panel shows the same data normalized to the Th activity. Note that both profiles show a general exponential decrease which can be used to assess the growth rate using the relationship that °Thxs ° = 230j jj imtiai g-X23ot showu ou both panels are for a steady growth rate of 1.15 mmMyr.
Because mixing consists of many small events which progressively move the sediment grains it is akin to diffusion and can be modeled as such following the mathematical approach of Guinasso and Schink (1975). °Pb and " Th decay as they are mixed downwards which leads to an activity profile in the sediment which decreases exponentially with depth (Fig. 12). The activity of the nuclide, A, is given by (Anderson et al. 1988) ... [Pg.520]

The profiles for most segregants, characterised by a rapid exponential decay with depth etched, are compatible with a single atom layer of segregant atoms at the fracture plane. The decay of the Auger electron intensity, /A, for the sputtering of atoms at the fracture plane is described by ... [Pg.184]


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See also in sourсe #XX -- [ Pg.50 , Pg.165 , Pg.166 , Pg.177 , Pg.179 , Pg.181 ]

See also in sourсe #XX -- [ Pg.266 ]




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