Distribution of deposition

Fig. 6. Cosine distribution of vaporized material from a point source (a) distribution of deposited material from a point source, and (b) distribution of film...

J. Horner, "A Study of the Effects of Some Variables on the Speed and Distribution of Deposits from Cyanide Copper Plating Solutions," 51 st... 

FIGURE 2.1 Distribution of deposited energy among different degrees of freedom as a function of time, represented by pt = -log t (sec). Note that, for exothermic reactions, low-grade heat can terminate above the level of absorbed energy. Luminescence can only alter the picture in a minor way. Reproduced from Mozumder (1969a), by permission of John Wiley Sons, Inc. ... 

Fig. 8.40 Retention (R, defined as deposited solids per unit length of section/total added suspended solids, mm 0 of suspended solids in the soil subsurface (a) distribution of deposited solids in coarse sand and silt loam, (b) relative deposition (defined as -ln(a/a), where a denotes initial amount of applied suspended solids and a. denotes measured amount of deposited solid mass per unit length of section at each depth) of suspended solids in silt loam and coarse sand leached by filtered and unfiltered effluents. (Vinten et al. 1983)...

Mass-transport deposition control occurs when the exchange current density P is high and the limiting current density is low. Ohmic resistance can be a cause of nonuniformity if there is an appreciable difference in solution resistance from the bulk of the solution to peaks or to recesses. Distribution of the current density will be such that ip > i. and peaks will receive a larger amount of deposit than will recesses. Distribution of deposit in the triangular groove under conditions of mass transport and ohmic control nonuniform deposition, with ip > is shown in Figure 10.14. 

Figure 10.14. Distribution of deposit in a triangular profile when and iy. < ip, high P...

In addition to catalyst pore structure, catalytic metals content can also influence the distribution of deposited metals. Vanadium radial profile comparisons of aged catalysts demonstrated that a high concentration of Co + Mo increases the reaction rate relative to diffusion, lowering the effectiveness factor and the distribution parameter (Pazos et al., 1983). While minimizing the content of Co and Mo on the catalyst is effective for increasing the effectiveness factor for HDM, it may also reduce the reaction rate for the HDS reactions. Lower space velocity or larger reactors would then be needed to attain the same desulfurization severity. 

The spatial distribution of deposited Ni and V in the reactor bed is determined by the activity of the catalyst and phenomenologically parallels that for profiles in individual pellets. Metals will tend to deposit near the reactor inlet with a highly active catalyst. A more even distribution or one skewed toward the reactor outlet is obtained for catalyst with less activity, as shown by Pazos et al. (1983). Generally with a typical small-pore (60-A), high-surface-area desulfurization catalyst, metals will concentrate near the inlet (Sato et al., 1971 Tamm et al., 1981). Fleisch et al. (1984) observed concentration maximums a short distance into the catalyst bed, as a probable consequence of the consecutive reaction path. 

The deposition of immune complexes along vascular basement membranes and the ensuing inflammatory response are the hallmark of immune complex disease. The distribution of deposition by and large determines the clinical features of the disease. In the human, factors governing the localization of immune complexes are incompletely understood, though it is presumed that blood flow physiology plays a role. Areas of relatively high-... 

The situation shown in Figure lc shows mass transfer from wide to narrow ones cages, which can be found at the evaporation interface. This effect explains the redistribution of the deposited component. The less adhesion the salt has to the surface of a non-uniform capillary, the higher the heterogeneity of its distribution in a capillary. To intensify or decrease mass transfer, and thus to control the dispersion and distribution of deposited compound, one can reasonably manipulate experimental conditions such as viscosity, surface tension, rate of evaporation, and addition of compounds that compete with the main adsorber during adsorption on the surface, etc.4... 

These two forms are self-consistent in that the same value of n can describe the energy dependence of the cross section and the distribution of deposited energies. In cases where the decomposition rate is fast compared to r, the integration over in Eq. (4) recovers Eq. (3). 

TMS deposition rate profiles in DC, 40-kHz, and 13.56-MHz discharges are shown for electrode in Figure 13.2. It can be seen that, regardless of the frequency of electrical power source used, a uniform deposition of TMS polymers was observed in the three plasma processes, although an appreciable edge effect occurred in the DC and a less pronounced effect occurred in the 40-kHz discharge when the substrate was used as the cathode or powered electrode. The uniform distribution of deposition rates justifies the use of single measurement at the center of the electrode to represent the characteristic deposition rate of a system. 

In principle, the rotating speed could be raised so that a considerable portion of powders is in gas phase however, it causes difficulty in feeding monomer and establishing a uniform distribution of deposition rate along the axis of tube length. In other words, maintaining powders in the gas phase is not the prime purpose of the tumbler reactor. 

Figure 14 Planar anterior and posterior images obtained following inhalation of two different-size pMDI aerosols, with the outline of the lung drawn from the anterior and posterior perfusion scans. The difference in geometry and distribution of deposited radioactivity between the anterior and posterior images reflects the proximity of that area of the lung to the gamma camera face.

Distribution of Deposited Radioactivity Within the Body Planar Imaging... 

V. Tsakova and D. Borissov, Electrochemical deposition of copper in polyaniline films -number density and spatial distribution of deposited metal crystals, Electrochem. Commun., 2, 511-515 (2000). 

During the flow of gas and dust in a dynamic scrubber is complex. This is explained by the fact that in the central part of the device is vane swirler. Analysis of fluid flow and distribution of deposited particles in a dynamic scrubber showed that the presence of turbulent diffusion particles concentrate at the vessel wall is not a thick layer, and in the form of gas and dust loosened concentrated layer (Fig. 2). 

XPS analysis combined with analysis by atomic force microscopy, AFM, determines differences in the surface distribution of deposited PMMA on the surface of polypyrrole depending on the type of solvent used (Figure 10.1.6). AFM, in this experiment, permitted the estimation of the surface roughness of polypyrrole. When PMMA was deposited from tetrahydrofuran, a poor solvent, it assumed a surface roughness equivalent to that of polypyrrole. Whereas PMMA, when deposited from a good solvent - CHCI3 ... 

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