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Meander

The Langmuir-Hinshelwood picture is essentially that of Fig. XVIII-14. If the process is unimolecular, the species meanders around on the surface until it receives the activation energy to go over to product(s), which then desorb. If the process is bimolecular, two species diffuse around until a reactive encounter occurs. The reaction will be diffusion controlled if it occurs on every encounter (see Ref. 211) the theory of surface diffusional encounters has been treated (see Ref. 212) the subject may also be approached by means of Monte Carlo/molecular dynamics techniques [213]. In the case of activated bimolecular reactions, however, there will in general be many encounters before the reactive one, and the rate law for the surface reaction is generally written by analogy to the mass action law for solutions. That is, for a bimolecular process, the rate is taken to be proportional to the product of the two surface concentrations. It is interesting, however, that essentially the same rate law is obtained if the adsorption is strictly localized and species react only if they happen to adsorb on adjacent sites (note Ref. 214). (The apparent rate law, that is, the rate law in terms of gas pressures, depends on the form of the adsorption isotherm, as discussed in the next section.)... [Pg.722]

Figure Bl.19.10. These images illustrate graphite (HOPG) features that closely resemble biological molecules. The surface features not only appear to possess periodicity (A), but also seem to meander across the HOPG steps (B). The average periodicity was 5.3 1.2 mn. Both images measure 150 mn x 150 mn. (Taken from [43], figure 4.)... Figure Bl.19.10. These images illustrate graphite (HOPG) features that closely resemble biological molecules. The surface features not only appear to possess periodicity (A), but also seem to meander across the HOPG steps (B). The average periodicity was 5.3 1.2 mn. Both images measure 150 mn x 150 mn. (Taken from [43], figure 4.)...
If 7 = 0, AT = 0, regardless of particle size. This is not expected, however, since chains emerging from a crystal face either make a highly constrained about-face and reenter the crystal or meander off into the liquid from a highly constrained attachment to the solid. In either case, a free-energy contribution is inescapable. [Pg.215]

Fig. 8.3-1 iMteral diffusion parameter vs distance from the source. This does not consider meander and building effects... [Pg.322]

Regulatory Guide 1.145 provides corrections to the sigmas to correct for the c ffects of wind meander at low windspeed - much the same effect as achieved in the CRACIT code. Figure 8.3-1, taken from this guide, shows how the horizontal dispersion coefficient varies with distance from the source. To calculate x/Q (the fractional attenuation) use formula (8.3-1) for a particular distance from the plant, say 1 km. [Pg.323]

For a step train, two neighboring steps collide when the fluctuation Wgq determined in (35) becomes the average step separation i. Therefore, the collision takes place for each step length Lcow 7 /T. To realize a large fluctuation, all the steps meander simultaneously. The step fluctuation for a long step (L > F gon) is reduced to the logarithmic form [3]... [Pg.872]

Resistivity measurements are done on meander shaped samples by the standard potentiometrie method in a stirred bath of liquid nitrogen relative to a dummy speeimen For this proeedure of residual re istometry the ultra-high measuring aeeuraey of 3.10 results below 300°C and of 3.10 for annealing treatments at higher temperatures. [Pg.221]

You must become aware of the pitfalls that exist in the search for regularities. The search is a meandering one, frequently taking wrong turns. It is inherent in the exploration of the unknown that not every step is an advance. Yet there is no other way to advance than by taking steps. How the search proceeds is best seen in a fable. The development of such a transparent example may help you see how a scientist searches for regularities. [Pg.3]

Flexible polyethylene separators have facilitated a novel cell construction the separator material, supplied in roll form, is wound so that it meanders around electrodes of alternating polarity (Fig. 23), requiring ribs in the cross-machine direction such profiles are available commercially [60],... [Pg.273]

Polyethylene separators offer the best balanced property spectrum excellent mechanical and chemical stability as well as good values for acid availability and electrical resistance have established their breakthrough to be the leading traction battery separator. Rubber separators, phenolic resin-resorcinol separators, and mi-croporous PVC separators are more difficult to handle than polyethylene separators their lack of flexibility does not allow folding into sleeves or use in a meandering assembly in addition they are more expensive. [Pg.276]

Catalyst material Pd/AfOj Pt/AfOj Rh/AfOj Meander net centerline length -2.2 mm... [Pg.282]

Figure 7.21 Methods of scanning thin-, er chronatograms. A -linear slit scanning B radial scanning C and D = peripheral scanning E = rig-zag scanning of an individual spot F > meander scanning of an individual spot. The arrows indicate the direction of plate movement. ... Figure 7.21 Methods of scanning thin-, er chronatograms. A -linear slit scanning B radial scanning C and D = peripheral scanning E = rig-zag scanning of an individual spot F > meander scanning of an individual spot. The arrows indicate the direction of plate movement. ...
Figure 2.9.11 shows schematically the experimental set-up of the ionic current device. The sample is packed between two electrodes that are shaped meander-like in order to avoid eddy currents due to pulsed field gradients. The high frequency filter is essential to prevent an antenna effect of the electrode cables inside the magnet. [Pg.225]

In this review, NMR analysis of the denatured state of staphylococcal nuclease is briefly reviewed in nontechnical language. Most of the work has come from the author s laboratory over the past eight years. The initial experiments, which only measure local structural parameters, reported small amounts of persisting helical structure, two turns, and indirect evidence for perhaps a three-strand beta meander. When applied to the denatured state in 6 M urea, the same experiments indicated that most of these features are lost. [Pg.27]

The most obvious feature of the 15N-1H correlation spectrum of A131A is what is missing All of the peaks corresponding to the first 30 residues are absent. In the native structure these residues form a three-strand beta meander which combines with a two-... [Pg.30]


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See also in sourсe #XX -- [ Pg.126 , Pg.127 ]

See also in sourсe #XX -- [ Pg.20 ]

See also in sourсe #XX -- [ Pg.11 , Pg.38 , Pg.39 , Pg.40 , Pg.41 , Pg.42 , Pg.43 , Pg.44 , Pg.45 , Pg.46 , Pg.47 , Pg.141 , Pg.144 , Pg.163 , Pg.164 , Pg.165 , Pg.169 , Pg.172 , Pg.173 , Pg.178 , Pg.179 , Pg.180 , Pg.187 ]




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Meander lines

Meander mixer

Meander model

Meander modulation

Meander region

Meander system

Meandering

Meandering

Meandering mixing channel

Mixer meander channel

Mixing by Helical Flows in Curved and Meander Micro Channels

P-meander

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