Limiting solubility

Pure phenol is a colourless crystalline substance, having m.p. 43°, and b.p. 182° on exposure to air, it slowly sublimes, and on exposure to light, develops a pink colour. It has a characteristic odour, and a limited solubility in water. Phenol in dilute aqueous solution has strongly antiseptic properties, but the crystalline substance should not be allowed to come in contact with the skin, as it may cause severe blistering. 

Iodoform reaction. To 0 5 ml. of acetone add 3 ml. of 10% KI solution and 10 ml. of freshly prepared sodium hypochlorite solution and mix well. A pale yellow precipitate of iodofonn is rapidly formed without heating. Acetophenone similarly gives iodoform, but the mixture must be shaken vigorously on account of the limited solubility of acetophenone in water. Benzophenone does not give iodoform. 

With the aim of catalysis of the Diels-Alder reaction of 5.1 with 5.2 by metallo micelles, preliminary studies have been performed using the surfactants 5.5a-c and 5.6 (Scheme 5.2). Unfortunately, the limited solubility of these surfactants in the pH region that allows Lewis-acid catalysis of the Diels-... 

Water-insoluble barium salts are poorly absorbed. In fact, barium sulfate is used as a contrast material for x-ray examination of the gastrointestinal tract based on its limited solubility andlow toxicity (52). Barium sulfate fed to mice at various levels up to 8 ppm dietary Ba ( 1.14 mg/kg-d as Ba " ) for three generations had no significant effects on growth, mortality, morbidity, or reproductive performance (53). 

Fig. 5. Schematic illustrating the soHd solubiUty between carbides. Solid line = complete solubiUty dashed line = limited solubility.

Except in the laboratoiy, batch reactors are mostly liquid phase. In semibatch operation, a gas of limited solubility may be fed in gradually as it is used up. Batch reaclors are popular in practice because of their flexibility with respect to reaction time and to the lands and quantities of reactions that they can process. 

It is not advisable to store large quantities of picrates for long periods, particularly when they are dry due to their potential EXPLOSIVE nature. The free base should be recovered as soon as possible. The picrate is suspended in an excess of 2N aqueous NaOH and warmed a little. Because of the limited solubility of sodium picrate, excess hot water must be added. Alternatively, because of the greater solubility of lithium picrate, aqueous 10% lithium hydroxide solution can be used. The solution is cooled, the amine is extracted with a suitable solvent such as diethyl ether or toluene, washed with 5N NaOH until the alkaline solution remains colourless, then with water, and the extract is dried with anhydrous sodium carbonate. The solvent is distilled off and the amine is fractionally distilled (under reduced pressure if necessary) or recrystallised. 

Limited solubility in selected perfluorinated solvents (unique amongst commercial fluoropolymers), enabling solution-cast ultra-thin coatings in the submicrometre thickness range. 

The checkers found that, in view of the limited solubility of triphenylene in ether (about 1 g. per 100 ml.), care must be exercised in the extraction to ensure that all the product is removed. 

To be effective, there must be a certain minimum concentration of inhibitor at the interface to be protected. Therefore, there must be sufficient inhibitor in the primer, and these inhibitors need to be soluble enough in water to enable transport of inhibitor to the oxide surface as water permeates the adhesive joint. However, too high of a solubility will rapidly deplete the primer layer of inhibitor resulting in a loss of protection. One of the fortuitous properties of zinc and strontium chromates is the limited solubility of these compounds in water (about 1.2 g/1 at 15°C [33]). 

Water-borne primers may or may not contain chromate-based corrosion inhibitors. The limited solubility of chromate salts in water makes them less than ideal for use in water-based primers, and much work has gone into developing alternatives [36], but the performance of recently developed water based primers using strontium chromate as the corrosion inhibitor is excellent, however, and appears equivalent to the solvent-borne analogues [37]. 

The white cesium fluoroxy sulfate precipitates from the reaction medium and may be kept for several months in the cold (0 to -15 °C) Metal surfaces can cause detonation of the reagent. The reaction scope of cesium fluoroxysulfate seems narrower than that of acetyl hypofluorite because of its limited solubility in organic solvents Cesium fluoroxysulfate has not been prepared with a fluorine-18 label. 

Although the reactants have only limited solubility in the catalyst phase, the rates of hydrogenation in [BMIM][SbFg] are almost five times faster than for the comparable reaction in acetone. All ionic catalyst solutions tested could be reused repeatedly. The loss of rhodium through leaching into the organic phase lay below the detection limit of 0.02 %. These results are of general importance for the field of... 

Temperature-dependent phase behavior was first applied to separate products from an ionic liquid/catalyst solution by de Souza and Dupont in the telomerization of butadiene and water [34]. This concept is especially attractive if one of the substrates shows limited solubility in the ionic liquid solvent. 

Despite the limited solubility of 1-octene in the ionic catalyst phase, a remarkable activity of the platinum catalyst was achieved [turnover frequency (TOP) = 126 h ]. However, the system has to be carefully optimized to avoid significant formation of hydrogenated by-product. Detailed studies to identify the best reaction conditions revealed that, in the chlorostannate ionic liquid [BMIM]Cl/SnCl2 [X(SnCl2) = 0.55],... 

Chlorine has limited solubility in water. Figure 9-85. KLa and Hol data of Vivian and Whitney, [76] Figure 9-86. Data for 1-in. ceramic Raschig rings. 

Variable results have been reported with this pigment and an examination of its inhibitive action has led to the conclusion that under rural and marine conditions, where the pH of the rain-water is above 5, it behaves as an inert pigment owing to its limited solubility. However, in industrial and urban areas, where the pH of the rain-water may be in the region of 4 or lower, it is converted into the more soluble monohydrogen phosphate. This reacts in the presence of oxygen, with the steel surface to form a mixture of tribasic zinc and ferric phosphates, which being insoluble protects the steel from further attack. 

Lipids are naturally occurring organic molecules that have limited solubility in water and can be isolated from organisms by extraction with nonpolar organic solvents. Fats, oils, waxes, many vitamins and hormones, and most nonprotein cell-meznbrane components are examples. Note that this definition differs from the sort used for carbohydrates and proteins in that lipids are defined by a physical property (solubility) rather than by structure. Of the many kinds of lipids, we ll be concerned in this chapter only with a few triacvlglycerols, eicosanoids, terpenoids, and steroids. 

The receptor compartment is defined as the aqueous volume containing the receptor and cellular system. It is assumed that free diffusion leads to ready access to this compartment (i.e., that the concentration within this compartment is the free concentration of drug at the receptor). However, there are factors that can cause differences between the experimentally accessible liquid compartment and the actual receptor compartment. One obvious potential problem is limited solubility of the drug being added to the medium. The assumption is made tacitly that the dissolved drug in the stock solution, when added to the medium bathing the pharmacological preparation, will stay in solution. There are cases where this may not be a valid assumption. 

Other poly(2,5-dialkoxy-1,4-phenylene vinylene)s have been prepared in a similar fashion [34, 35, 40, 41]. Alternatively, a soluble a-halo precursor polymer 17 may be obtained by using less than one equivalent of base (Scheme 1-6). This may then be converted into fully conjugated material 16 by thermal treatment. This halo-precursor route may be preferred if the fully conjugated material has limited solubility or if incomplete conversion is desired. 

The 50%-strength liquid tannin products are particularly viscous, and some sediment is to be expected because of limited solubility of certain constituents at high strength (ellagic acid ). Tannins stored in drums should be mixed before use or before transfer into a day tank. 

As a result of the limited solubility of MEKO, it is often formulated with other boiler treatment ingredients such as filming and neutralizing amines, sulfite, or erythorbates, which permit increased concentration, improved stability, and better overall effectiveness. 

A derivative of the triple-blend formulation to include DEHA for control of 02 (resulting from air in-leakage to the condensate line) is shown next. The concentration of DEHA must not be too high, and the blending process requires careful control because of the limited solubility of hydroquinone. 

Sodium alcohol sulfates have a limited solubility compared to sodium alcohol ether sulfates and are more suitable for cream, pearlized, and paste shampoos. Alcohol sulfates are more frequently used in general shampoo formulations in the United States than in Europe. Europe has moved toward alcohol ether sulfates for historical and traditional reasons, different availability of ethylene oxide, and possibly other technical reasons such as the more favorable dermatological properties of alcohol ether sulfates and their better behavior in hard waters. Triethanolamine alcohol sulfates are widely used in shampoos because of their comparatively high solubility in water, good foaming properties, and low irritancy. 

Intercalation from solutions in nonaqueous solvents (S21). This method may suffer from the drawback that final stoichiometries may not correspond to equilibrium conditions, because of partial leaching out of metal halide. For this reason, some chlorides can be intercalated only from solvents in which they have limited solubility iLS). It has often been the practice to wash intercalates with solvents to remove the excess of intercalant this may lead to stoichiometries lower than the original ones. The two-ampoule method may, therefore, be preferable (H24). 

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