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Saturation composition

Suppose the grain size for phase A is very small, leading to very large total surface area for reaction. That is, A >A . Then (w - 1) (w - 1), meaning the fluid composition is such that it is very close to the saturation composition of phase A, whereas phase B is significantly undersaturated. After solving for vA and w , the reaction rate of A and B can be calculated if lA and are known. [Pg.439]

Fig. 4. Photograph of a sample that was cut from a water saturated composite sheet consisting of Super-Slurper (cellulose chain extended with hydrolysed polyacrylodnitrile) particles (85% by weight) enmeshed in PTFE microfibers. The smaller sample, which had been cut to the same size and shape from the same water saturated composite film, was allowed to evaporate to dryness at ambient room conditions. The original size and shape (represented by the larger sample) was re-established when the smaller sample was allowed to re-swell to saturation in very dilute aqueous NaOH... Fig. 4. Photograph of a sample that was cut from a water saturated composite sheet consisting of Super-Slurper (cellulose chain extended with hydrolysed polyacrylodnitrile) particles (85% by weight) enmeshed in PTFE microfibers. The smaller sample, which had been cut to the same size and shape from the same water saturated composite film, was allowed to evaporate to dryness at ambient room conditions. The original size and shape (represented by the larger sample) was re-established when the smaller sample was allowed to re-swell to saturation in very dilute aqueous NaOH...
Fig. 20. Schematic representation of a composite membrane (Figs. 1 and 7) at liquid saturation showing a single gelled particle enmeshed in PTFE microfibers as described in the text. The bold straight lines represent the PTFE fibers. The entangled network of curved lines represent the crosslinked polymer that supports the liquid saturated gel. Each empty circle (o), superimposed on the curvy lines, represents a set of molecules ( Fig. 20. Schematic representation of a composite membrane (Figs. 1 and 7) at liquid saturation showing a single gelled particle enmeshed in PTFE microfibers as described in the text. The bold straight lines represent the PTFE fibers. The entangled network of curved lines represent the crosslinked polymer that supports the liquid saturated gel. Each empty circle (o), superimposed on the curvy lines, represents a set of molecules (<x8, as defined in Eq. 20) adsorbed to an accessible monomer unit. The filled squares ( ) represent liquid molecules that are sorbed by the gelled particles, but not immobilized by adsorption to the polymer molecules. The empty triangles (a) represent liquid molecules that surround the liquid saturated gel particles enmeshed in the composite membrane. The excess liquid, in contact with the external surface of the liquid saturated composite membrane, is not shown...
Canola Oil Canola oil is obtained from low erucic acid, low glucosinolate rapeseed. The unique polyunsaturated fatty acid and low saturated composition of canola oil differentiates it from other oils. It has a higher oleic acid (18 1) content (55%) and lower linoleic acid (18 2) content (26%) than most other vegetable oils, but it contains 8-12% of linolenic acid (18 3) (58). Canola oil is most widely used in Canada and is considered a nutritionally balanced oil because of its favorable ratio of near 2 1 for linoleic to linolenic acid content. Unlike most other edible oils, the major breakdown products of canola oil are the cis, trans- and tram, trans-2,4-heptadienals with an odor character generally described as oily, fatty, and putty. Stored canola oil shows a sharp increase in the content of its degradation products, which are well above their odor detection thresholds. The aroma is dominated by cis, tram-, tram, frani-2,4-heptadienals, hexanal, nonanal, and the cis, trans- and... [Pg.443]

Gas adsorption is a phenomenon in which a gas molecule is removed from the gaseous phase by a solid surface. (Fig. 3.4.3) The gas itself is called the adsorptive and the concentrated gas on the surface in high density is called the adsorbate. The substance adsorbing the gas is called the adsorbent and the phenomenon in which the gas adheres to the surface (pores) is called adsorption. The phenomena in which the adsorbents are taken into the solid are called absorption or occlusion. Occlusion is a special case where gas is reversibly adsorbed into a crystal lattice with intrinsic saturated composition. These phenomena are further divided into physisorption and chemisorption based on the strength of the interaction energy between the gas and the solid. When the heat of adsorption is greater than 20 kj mol-1 it is classified as chemical adsorption, but the classification is not strict. [Pg.317]

There is a considerable difference between the number of active sites as determined from the limiting number of spins 7 X 1014/sq. meter, and from the saturation composition. This can be partly explained by the magnitude of the experimental errors involved. Some prohibiting mechanism may exist which has not been taken into account in the model. Thus, use of a site for cation formation may render inactive a certain number of neighboring sites. [Pg.325]

After bonding process, annealing is proceeded. At the eutectic point, the liquid phase maintains gold diffusion into the silicon until the saturation composition is reached. During this process, the ratio of gold and silicon in the eutectic Au-Si alloy has been changed thus, the alloy composition will be solidified. This also happens when the temperature decreases below the eutectic point. In either case, the solidified composition will be annealed and this should be performed under an inert gas flow, such as nitrogen. [Pg.490]

Solution. The equilibrium data for this Type 2 system [Hunter and Brown, Ind. Eng. Chem. 39, 1343 (1947)] show to be nearly constant with an average value of 1.4. The saturated compositions, taken from the phase diagram, are as follows Xcf = 0.447, Xaf = 0.447 XoPg 0.80, Xap = 0.042 Xcp = 0.046, Xapj ... [Pg.200]

At the saturation point, there is not yet any solids formation, and so the quantity of dissolved solids is unchanged. The amount of water remaining corresponds to the saturation composition given above. Of the total, 12.3% or 14.03 units of water have evaporated. Evaporation continues, but since it stops short of the saddle curve, no sulfate drops from solution. The residual water therefore is 0.57/0.065 = 8.78. The remaining NaCl in solution is 36.7 g/100 g water, or 0.367 x 8.78 3.22. The rest of the salt, about... [Pg.648]

At first, we will expound on SWNTs. Purified SWNTs show a reversible saturation composition of Lii.yCe, simulation results show that possibility of Li intercalation in SWNT bundles can reach a high saturation density of LisCe, higher than the LiCe ideal value for graphite and reported MWNTs. During the Li intercalation process, the Li fills the SWNT bundle continuously and randomly, thus there are no staging phenomena, which are opposed to that of graphite. ... [Pg.130]

Composition and saturation compositions of inorganic chemicals in the feed water... [Pg.231]

If the reaction rate is very slow, the concentration difference between Cjg and Cb grows closer. In the limit, Cb is equal to Cg and the maximum reaction rate is obtained at the saturation composition. It almost all cases it is assumed that the continuous or liquid phase is well mixed, so that no gradients exist. This is true in most equipment because the blend time is usually small compared to the mass ttansfer time. This means that Cb is the same at all places in the vessel. [Pg.793]

J. A. Luker and Thomas Gniewek, Saturation Composition of Steam— Helium—Water Mixtures PVT Data and Heat Capacity of Superheated Steam— Helium Mixtures, USAEC Report AECU-3299, Syracuse University Research Institute, July 29, 1955. [Pg.126]

The enthalpies of vaporization for the pure components are in excellent agreement with experiment, as is the composition of the azeotrope. The enthalpy of the saturated vapor is also in... [Pg.90]

Figure 6.25a shows the same grand composite curve with two levels of saturated steam used as a hot utility. The steam system in Fig. 6.25a shows the low-pressure steam being desuperheated by injection of boiler feedwater after pressure reduction to maintain saturated conditions. Figure 6.256 shows again the same grand composite curve but with hot oil used as a hot utility. [Pg.186]

Generally the properties of mixtures in the ideal gas state and saturated liquids are calculated by weighting the properties of components at the same temperature and in the same state. Weighting in these cases is most often linear with respect to composition ( ), ... [Pg.109]

Molecular adsorbates usually cover a substrate with a single layer, after which the surface becomes passive with respect to fiirther adsorption. The actual saturation coverage varies from system to system, and is often detenumed by the strength of the repulsive interactions between neighbouring adsorbates. Some molecules will remain intact upon adsorption, while others will adsorb dissociatively. This is often a frinction of the surface temperature and composition. There are also often multiple adsorption states, in which the stronger, more tightly bound states fill first, and the more weakly bound states fill last. The factors that control adsorbate behaviour depend on the complex interactions between adsorbates and the substrate, and between the adsorbates themselves. [Pg.294]

Saturation temperatures of sodium chloride dihydrate at these temperatures NaCl 2H2O separates leaving the brine of the eutectic composition (E). [Pg.445]

Determine the equilibrium composition of saturated solution of AgCl. Assume that the solubility of AgCl is influenced by the following reactions. [Pg.177]

RandomiZation/Interesterification. Transesterification occurs when a carboxyUc acid (acidolysis) or alcohol (alcoholysis) reacts with an ester to produce a different ester (20). Ester—ester interchange is also a form of transesterification. If completely unsaturated triglyceride oil (UUU) reacts with a totally saturated fat (SSS) in the presence of an active catalyst such as sodium, potassium, or sodium alkoxide, triglycerides of intermediate composition may be formed. [Pg.126]

Fats and oils may be synthesized in enantiomerically pure forms in the laboratory (30) or derived from vegetable sources (mainly from nuts, beans, and seeds), animal depot fats, fish, or marine mammals. Oils obtained from other sources differ markedly in their fatty acid distribution. Table 2 shows compositions for a wide variety of oils. One variation in composition is the chain length of the fatty acid. Butterfat, for example, has a fairly high concentration of short- and medium-chain saturated fatty acids. Oils derived from cuphea are also a rich source of capric acid which is considered to be medium in chain length (32). Palm kernel and coconut oils are known as lauric oils because of their high content of C-12 saturated fatty acid (lauric acid). Rapeseed oil, on the other hand, has a fairly high concentration of long-chain (C-20 and C-22) fatty acids. [Pg.128]

Crimp. The tow is usually relaxed at this point. Relaxation is essential because it gready reduces the tendency for fibrillation and increases the dimensional stabiUty of the fiber. Relaxation also increases fiber elongation and improves dye diffusion rates. This relaxation can be done in-line on Superba equipment or in batches in an autoclave. Generally saturated steam is used because the moisture reduces the process temperatures required. Fiber shrinkage during relaxation ranges from 10 to 40% depending on the temperature used, the polymer composition used for the fiber, and the amount of prior orientation and relaxation. The amount of relaxation is also tailored to the intended apphcation of the fiber product. [Pg.282]

Gas oil fractions (204—565°C) from coal Hquefaction show even greater differences in composition compared to petroleum-derived counterparts than do the naphtha fractions (128). The coal-gas oils consist mostly of aromatics (60%), polar heteroaromatics (25%), asphaltenes (8—15%), and saturated... [Pg.91]

The reinforcing ply acts as the carrier for the plastic resin during intermediate processing steps known as saturation and B-staging. It is this ply that together with the resin makes a laminate a composite material, and the layering of these pHes that makes the final product a laminate. [Pg.532]

Quicklime and hydrated lime are reasonably stable compounds but not nearly as stable as their limestone antecedents. Chemically, quicklime is stable at any temperature, but it is extremely vulnerable to moisture. Even moisture in the air produces a destabilizing effect by air-slaking it into a hydrate. As a result, an active high calcium quicklime is a strong desiccant (qv). Probably hydrate is more stable than quicklime. Certainly hydrated lime is less perishable chemically because water does not alter its chemical composition. However, its strong affinity for carbon dioxide causes recarbonation. Dolomitic quicklime is less sensitive to slaking than high calcium quicklime, and dead-burned forms are completely stable under moisture-saturated conditions. [Pg.167]


See other pages where Saturation composition is mentioned: [Pg.84]    [Pg.374]    [Pg.499]    [Pg.421]    [Pg.298]    [Pg.131]    [Pg.92]    [Pg.84]    [Pg.374]    [Pg.499]    [Pg.421]    [Pg.298]    [Pg.131]    [Pg.92]    [Pg.202]    [Pg.141]    [Pg.128]    [Pg.471]    [Pg.286]    [Pg.23]    [Pg.87]    [Pg.129]    [Pg.175]    [Pg.188]    [Pg.190]    [Pg.44]    [Pg.264]    [Pg.440]    [Pg.183]    [Pg.118]    [Pg.291]   
See also in sourсe #XX -- [ Pg.325 ]




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