Influence of solids

Melting, a major physical event, has small, subtle effects on shock-compression wave profiles. The relatively small volume changes and limited mixed-phase regions result in modest, localized changes in loading wave speed. Consequently, shock-induced melting and freezing remains an area with little data and virtually no information on the influence of solid properties and defects on its kinetics. 

Vijh, A. K., The Influence of Solid State Cohesion of Metals on Their Pitting Potentials , Corros. Sci., 12, 935 (1972)... 

In this chapter, we will review the consequences of solid deformation in the kinetics of the spreading of a liquid on a soft material, in both wetting and dewetting modes. The influence of solid deformation induced by the liquid surface tension will be shown in the case of a liquid drop placed on a soft elastomeric substrate and in the case of an unstable liquid layer dewetting on a soft rubber. The impact of solid deformation on the kinetics of the wetting or dewetting of a liquid will be analyzed theoretically and illustrated by a few concrete examples. The consequences of solid deformation in capillary flow will be also analyzed. 

This key paper was followed by a flurry of activity in this area, spanning several years." " "" A variety of workers reported attempts to deconvolute the temperature dependence of carbene singlet/triplet equilibria and relative reactivities from the influence of solid matrices. Invariably, in low-temperature solids, H-abstraction reactions were found to predominate over other processes. Somewhat similar results were obtained in studies of the temperature and phase dependency of the selectivity of C-H insertion reactions in alkanes. While, for example, primary versus tertiary C-H abstraction became increasingly selective as the temperature was lowered in solution, the reactions became dramatically less selective in the solid phase as temperatures were lowered further. Similar work of Tomioka and co-workers explored variations of OH (singlet reaction) versus C-H (triplet reaction) carbene insertions with alcohols as a function of temperature and medium. Numerous attempts were made in these reports to explain the results based on increases in triplet carbene population... 

The simplest correlations are of the form shown by Eq. (15), in attempts to recognize the strong influence of solid concentration (i.e., suspension density) on the convective heat transfer coefficient. Some examples of this type of correlation, for heat transfer at vertical wall of fast fluidized beds are ... 

Potthoff, M., and Bohnet, M., Influence of Solids Concentration and Static Mixers on Fluid Dynamics in Three-Phase Fluidized Bed Bioreactors, Chem. Eng. Technol., 16 147 (1993)... 

Percent elongation at rupture as a function of the composition of mixed of polypropylene and polyethylene indicating influence of solid state phases on strength and extensibility. 

Wissing, S. A. and Muller, R. H., The influence of solid hpid nanoparticles on skin hydration and viscoelasticity in vivo study. Eur. J. Pharm. Biopharm., 56, 67-72, 2003. 

Figure 15.6 Influence of solid pigments on the NIR absorbance spectra of coiored poiypropyiene carpets. Note that as the carpets change from dark biue (bottom trace) to cream coior (top trace) the baseiine shift increases, the baseiine tiit increases, and the intensity of the absorbance peaks decreases. Reprinted with permission from Rodgers (2002). ...

Figure 5. Influence of solids content on flux for Latex...

Epoxides can also serve as effective carbocyclization promotors, either through a polyene cyclization, as in the biomimetic epoxy-olefin cyclization of 100 in the presence of boron trifluoride etherate <99CC325>, or by a Friedel-Crafts approach, as exemplified by the cycli-alkylation of arylalkyl epoxides 102 under the influence of solid acid catalysts <99EJOC837>. 

Adequacy of Thermodynamic Data. Data on several important aluminosilicates appear to be insufficient for a detailed discussion of all equilibria. Information on the influence of solid solutions or coprecipitated phases on thermodynamic properties appears to be rather limited, as is that for metastable non-stoichiometric oxides (e.g., of manganese) and surface complexes. 

During the last two decades it has been found that there is a special group of chemical reactions, essentially redox reactions, for which the catalytic influence of solids can be interpreted in terms of the catalyst s electronic structure and the controlled variations of that structure. The study of single-phase catalysts and the relationship between function and electronic structure of solid state catalysts show that redox reactions may be divided into two classes. Donor reactions are reactions in which the rate-determining step involves an electron transition from the reactant molecule to the catalyst acceptor reactions are those where the reactant must accept electrons from the catalyst in order to form the activated state. Broadly speaking, donor reactions mobilize reducing agents like... 

Elperin, I. T., Meltser, V. L., Levental, L. E. and Israfailov, T. D. (1971). Influence of solid particles concentration on their motion in impinging jets. Proc. of the Academy ofBSSR, Series of Physical-Energy Sci., 4, 66-7. 

Reddy M.M. and Gaillard W.D. (1981) Kinetics of calcium carbonate (calacite)-seeded crystallization Influence of solid/solution ratio on the reaction rate constant. J. Colloid Interface Sci. 80, 171-178. 

Wardrop J, Law D, Qiu Y, Engh K, Faitsch L, Ling C. 2006. Influence of solid phase and formulation processing on stability of Abbott-232 tablet formulation. J. Pharm. Sci. 

Theuns, E., Merci, B., Vierendeels, J., and Vandevelde, P. Influence of solid material properties on numerical large scale flame spread calculations. Interflam, Edinburgh, U.K., 2004, pp. 1245-1256. 

The exponents are close to those observed by Zwieter-ing (eq 5). Buurman [27] extended the theory of Baldi et al. and found a theoretical relationship for the influence of solids concentration ... 

Much more information is available on the product ky a than on kl and a separately. For low solids concentrations it may be assumed that the solids do not affect the value of A a, so that the existing relations for two-phase gas-liquid reactors can be applied. For reviews on these relationships, see Lee and Foster [76], for draft tube slurry reactors Goto et al. [77], for bubble columns Deckwer and Schumpe [78] and Deckwer [79], and for stirred tank reactors Mann [80] and Schluter and Deckwer [81]. Despite of much research published on the influence of solids on k a there is still no universally applicable relation describing the influence of all types of particles in any weight fraction in any liquid. 

Only some scattered information on the influence of pressure and gas density on k a is available. Recently, Dewes et al. [51] reported results from a 0.115m diameter column operated in all but the chum-turbulent regime, both at 1 bar and 8 bar, with 2 vol% of solids. The influence of solids was negligible (see Fig. 8), but, as expected from Wilkinson s findings on the influence of pCl on r< [44], A Ltf increased substantially with pressure. Dewes et al. [51] were able to show that the pressure affected a only, with A l- remaining independent of both pressure and the presence of solids. 

Figure 9. Influence of solids on k a in a 0.15 m diameter stirred-tank reactor (I) FejOjfcO.Sptm) in 1-tetradecene (2) BaSO. (<1 ftm) in tetradecene (3) Fe2Oj in 1,2,4-trimethylbenzene (4) BaS04 in 1,2,4-trimethylbenzcne (5) sea sand (<80//m) in water (6) kieselguhr (<50 m) in water. Stirrer speed 21 rps except for experiments with trimethyl benzene (16 rps) (compiled from several figures of Oguz et al. [87]).

Few comprehensive studies have appeared concerning the influence of solids on k a in stirred tank reactors. Oguz et al. [87] measured k a in various slurries in a baffled 14.5 cm diameter stirred-tank reactor. Water and three organic liquids ( -butanol, 1-tetradecene and 1,2,4-trimcthylbenzcnc) were used as liquid phases. The particles applied varied in density from 2070 to 4720 kg m 3 and average particle sizes from 80 pm to below 1 pm. The observed cflccts of the particles on k a appear at first sight to be confusingly different for different slurry systems (sec Fig. 9). However, if the increase in apparent slurry viscosity due to the presence... 

Schmitz et al. [89] also reported on the influence of solids on kEa in stirred tanks. Although they applied only one type of solid (glass beads of 88 and 320 pm average diameter) in aqueous solutions, their study is of particular interest because of the wide range in variation of liquid viscosity applied by adding carboxy methylcellulose and by investigating the scale-up aspects by measuring both in a 20 cm and a 45 cm diameter stirred tank. As Schmitz et al. [89] also point out, their result. 

Figure 11. Influence of solids fraction on k a in stirred tanks (a) sodium sulfite aqueous solution [89] (b) tap water [90] (c) NaCl aqueous solution [91],...

In the presence of some coagulated soles it is possible to produce stable foams in which there are no surfactants [89]. Usually it is assumed [83] that the presence of solid particles in foams leads to delay of drainage because the Pateau borders become narrower, their walls become rougher and the particles form local caps. An analogous delay of drainage results from emulsion drops that enter the Plateau borders [90]. However, as pointed out in [84], the influence of solid particles on foam drainage rate should not be considered synonymously. 

Fig. 32. Influence of solids circulation rate on gas backmixing at a velocity higher than the incipient fast fluidization velocity (after Li and Wu, 1991).

Fig. 24. Influence of solids circulation ratio on separation efficiency for first-stage separation (after Li and Wang, 1992).

McMurray, J. S., Lewis, C. A., and Obeyesekere, N. U. (1994) Influence of solid support, solvent and coupling reagent in the head-to-tail cyclisation of resin-bound peptides. Pept. Res. 7, 195-206. 

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