Surface ratio

Fin-tube siirface/bare-tiibe surface ratio is 16.9. 

Base Bare-tuhe external surface 1 in. o.d. hy 12 B.W.G. hy 24 ft. 0 in. steel tube with 8 aluminum fins per inch V -in. high. Steel headers. 150 lh./sq. in. design pressure. V-helt drive and explosion-proof motor. Bare-tuhe surface 0.262 sq. ft./ft. Fin-tuhe surface/hare-tuhe surface ratio is 16.9. 

Aluminum-sheathed cables should not be connected to other cables because aluminum has the most negative rest potential of all applicable cable sheathing materials. Every defect in the protective sheath is therefore anodically endangered (see Fig. 2-5). The very high surface ratio SJS leads to rapid destruction of the aluminum sheathing according to Eq. (2-44). Aluminum can also suffer cathodic corrosion (see Fig. 2-11). The cathodic protection of aluminum is therefore a problem. Care must be taken that the protection criterion of Eq. (2-48) with the data in Section 2.4 is fulfilled (see also Table 13-1). Aluminum-sheathed cables are used only in exceptional cases. They should not be laid in stray current areas or in soils with a high concentration of salt. 

Cathodes made of steel tube rings 10 m in diameter are used m the internal protection of several 30-m-high caustic soda stirring tanks, each with a surface area of 3100 m, The cathodes were insulated and mounted on supporting brackets. The current supply was via armored parallel connected cables. One-inch bolts were used for the entrance in the tank wall as shown in Fig. 21 -13 for a feed current of 500 A. The size of the cathodes has to be such that they can maintain sufficient cathodic protection current. The surface ratio of the object to be protected and the... 

Coefficients are based on outside bare tube surface for 1-in. O.D. lubes with 8 extruded Al fins/in., /ain. high, 16.9 surface ratio. 

For the rough surface, ckw > 0 and one obtains that 7ig > —s must hold. Eq. (71) leads also to the following lower bound for the surface ratio 0 ... 

Recent development of the use of reversed micelles (aqueous surfactant aggregates in organic solvents) to solubilize significant quantities of nonpolar materials within their polar cores can be exploited in the development of new concepts for the continuous selective concentration and recovery of heavy metal ions from dilute aqueous streams. The ability of reversed micelle solutions to extract proteins and amino acids selectively from aqueous media has been recently demonstrated the results indicate that strong electrostatic interactions are the primary basis for selectivity. The high charge-to-surface ratio of the valuable heavy metal ions suggests that they too should be extractable from dilute aqueous solutions. 

For the analysis of primary particles it is possible to calculate the spherical diameter for a particle from Rg described above as P = (5/3) Pg or 2.6 Rg. It is also possible to calculate diameter for a particle through the volume/surface ratio, which is called the Sauter mean... 

Figure 4. Variation of the surface ratio n(Ni)/n(Ni)+N(Fe) as a function of bulk Ni/Ni+Fe content in ThNij Fes-x alloys.

Thermodynamic control (Figure 1, right) is based on adsorption of substances until quasi-equilibrium stage. In this case, the surface ratio of the adsorbed species is defined by the ratio of products of their concentration and binding constant. This deposition is much less influenced by poorly controllable fluctuations of external conditions and provides much better reproducibility. The total coverage can be almost 100%. Because of these reasons, the thermodynamic control is advantageous for preparation of mixed nanostructured monolayers for electrochemical applications including a formation of spreader-bar structures for their application as molecular templates for synthesis of nanoparticles. 

The results of this work are given in Table II. It can be seen that the CO/Fe surface ratio varies from sample to sample. This probably results from the presence of two surface species, in different relative amounts, on each sample. This is explained in the discussion section. 

The dissociation of the complex upon exposure to a pure solution after it has reached its equilibrium value may be examined similarly. At time t = 0, 0 = 0 = k/( I k) = KC Z(1 + KC ), where Cg is the bulk concentration that was used during the adsorption step preceding the desorption process. Assuming that the volume-to-surface ratio is large enough for the bulk concentration of B to remain negligible throughout the experiment, the variation in the surface concentration with time obeys the equation... 

Although bulk- and surface-decorated samples agree broadly in terms of optimal Pt Ru surface ratios for MeOH oxidation, there is less agreement with practical PtRu catalysts, although the data are sparse. This would suggest that PtRu particles show Pt-segregated surfaces as predicted by theoretical calculations. 

Eq. 2 V/S is the volume to surface ratio Phi, the torsion angle between the C2 atom and the B ring o, the Hammett coefficient of the B ring dV, volume difference between substrate and flavonoid dL, length of the C3 side chain (p, dipole moment and C3, C5, and C4 the electron density occurring at these atoms. 

The parameter Wi which takes the concentration of the non-aggregated surfactant in the oil into account - the cpc - is directly proportional to the radius of the reverse micelles rrev. mic. because of the volume to surface ratio of spherical droplets [64-66] ... 

These considerations are important also in view of the processes of division and/or fusion of vesicles. In particular, when a vesicle divides up, and the total surface area remains constant, the total volume must decrease. This means that water must be eliminated in the process, so as to keep the volume to surface ratio constant. Conversely, when two vesicles fuse with each other, with a constant surface area (no fresh surfactant being added), the total volume must increase to keep the volume/surface constant and water must come in. This important, characteristic feature of vesicles is represented in Figure 9.27. 

In ESI MS, a dissolved sample is sprayed through a capillary in an electric field which is situated in front of the vacuum inlet of the mass spectrometer [2]. Thus, in contrast to most other ionization techniques performed in high vacuum, the ionizahon process takes place at the atmospheric pressure. After leaving the capillary, the solvent forms a so-called Taylor-cone, which further forms a filament and finally, the spray of small droplets (Figure 14.2). These droplets carry charges on the surface this is frequently supported by the acidification of the solvent. The droplets shrink is caused by the evaporation of the solvent. This leads to an increase of the charge-per-surface ratio, finally... 

The relative influence of the surface (or interface) effects, of course, must decrease with increasing thickness t of the layer(s). Since the surface effects contribute per unit surface area , one defines, for the layer, effective parameters such that Beff, or heff, equals gbuik 2bsurt/t. Here, the factor 2 is put in, because a layer has two surfaces. In practice, this simple l/t dependence works satisfactorily. For nanocrystallites, both the volume fraction and the volume to surface ratio of the crystallites (i.e. their radius) must be taken into account (see also section 8). In connection to these effects, (non-linear) contributions to the magnetoelastic coefficients due to surface strains and surface roughness are expected to be considerable. 

C. This figure is appropriate for adiabatic polymerization, which approximates reality in reactive processing of large articles with high volume-to-surface ratios. In this case, it is impossible to remove the heat effectively and to avoid intense local temperature jumps. Therefore, it is essential to know how to calculate temperature increase for reactions proceeding in non-isothermal conditions. The time dependence of viscosity in this situation can be written as... 

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