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Ether combination table

These higher foaming properties are very useful for such cosmetic formulations as shampoos, showerbaths, and so on. This is the same with the forming of fine bubbles and the improving of foam stability of other surfactants such as, for example, alkyl ether sulfates due to the combination with ether carboxylates [57,67-69] (Table 9). [Pg.332]

To 10 ml of urine add sufficient phosphoric acid or tartaric acid to adjust the pH to 3, extract with two 30-ml portions of ether, combine the ether extracts, wash with 5 ml of water, add the washing to the sample, and retain the aqueous solution for later exhaction. Extract the combined ether extracts with 5 ml of saturated sodium bicarbonate solution and retain die aqueous solution for possible examination for the presence of salicylate (Strong Acid Fraction A). Extract the ethereal solution with 5 ml of 0.5M sodium hydroxide and retain the extract for examination for the presence of barbiturates and other weakly acid substances (Weak Acid Fraction B)—see Table 5. [Pg.10]

If the diamine portion of the polyurethane is desired, the solution is extracted with several 25 ml portions of diethyl ether. These are combined, the ether removed, and the spectrum of the diamines can then be identified from reterence infrared spectra and correlation tables. The solution is then neutralized and acidified slightly with nitric or hydrochloric acid and the glycols remaining in solution from saponification of a polyester foam must be steam-distilled to effect recovery. [Pg.329]

Later it was synthesized in a batch process from dimethyl ether and sulfur thoxide (93) and this combination was adapted for continuous operation. Gaseous dimethyl ether was bubbled at 15.4 kg/h into the bottom of a tower 20 cm in diameter and 365 cm high and filled with the reaction product dimethyl sulfate. Liquid sulfur thoxide was introduced at 26.5 kg/h at the top of the tower. The mildly exothermic reaction was controlled at 45—47°C, and the reaction product (96—97 wt % dimethyl sulfate, sulfuhc acid, and methyl hydrogen sulfate) was continuously withdrawn and purified by vacuum distillation over sodium sulfate. The yield was almost quantitative, and the product was a clear, colorless, mobile Hquid. A modified process is deschbed in Reference 94. Properties are Hsted in Table 3. [Pg.201]

Commercially available PVB resias are generally soluble in lower molecular weight alcohols, glycol ethers, and certain mixtures of polar and nonpolar solvents. A representative Hst is found in Table 5. Grades with lower vinyl alcohol content are soluble in a wider variety of solvents. A common solvent for all of the Butvar resins is a combination of 60 parts of toluene and 40 parts of ethanol (95%) by weight. [Pg.452]

Deep fluorinalion of alkanes, ethers, acid fmlides, esters, alkyl chlorides, most ketones, ketals, orthoesters, and combinations of these functional groups produces principally the perfluonnated analogues (Table 2) Chlorine substituents (or chloro groups) usually survive fluorination... [Pg.104]

Tetrasubstituted phosphonium halides are just as effective as their ammonium counterparts. A combination of tetraphenylphosphonium bromide and either 18-crown-6 or polyethylene glycol dimethyl ether with spray-dried potassium fluoride converts 4-chlorobenzaldehyde to 4-fluorobenzaldehyde in 74% yield [67] In addition, the halogen of a primary alkyl chloride or bromide is easily displaced by fluorine in aqueous saturated potassium fluoride and a catalytic amount of hexadecyltributylphosphonium bromide [68] (Table 7 Procedure 4, p 194)... [Pg.191]

Typical normal-phase operations involved combinations of alcohols and hexane or heptane. In many cases, the addition of small amounts (< 0.1 %) of acid and/or base is necessary to improve peak efficiency and selectivity. Usually, the concentration of polar solvents such as alcohol determines the retention and selectivity (Fig. 2-18). Since flow rate has no impact on selectivity (see Fig. 2-11), the most productive flow rate was determined to be 2 mL miiT. Ethanol normally gives the best efficiency and resolution with reasonable back-pressures. It has been reported that halogenated solvents have also been used successfully on these stationary phases as well as acetonitrile, dioxane and methyl tert-butyl ether, or combinations of the these. The optimization parameters under three different mobile phase modes on glycopeptide CSPs are summarized in Table 2-7. [Pg.52]

A solution of (R)-oxynilrilase (F.C 4.1.2.10, 100 pi., 1000 unils/ml.) is dropped onto 1.5 g of Avicel cellulose (soaked in 0.02 M sodium acetate buffer. pH 4.5). 20 mL of diisopropyl ether are added, followed by 5 mmol of ketone and 200 pL of hydrocyanic acid, and the mixture is stirred (Table 3). The catalyst is filtered off. washed with diisopropyl ether, and the combined filtrates are concentrated. [Pg.670]

Van Paassen [57,67] reported a synergistic decrease of the skin and eye irritation level of sodium lauryl ether sulfate by combination with lauryl ether carboxylates. The investigations have been carried out using the Draize eye irritation test and human patch test (Tables 13 and 14). Furthermore, measurements by in vitro methods, the Zein test, and the red blood cell test show low to no irritancy [251-253]. [Pg.349]

The rate constants kTS and kST define an equilibrium constant (ATeq) connecting the singlet and triplet carbenes. An estimate of Ktq, and hence AGSX, for BA can be obtained from the experiments described above. The time resolved spectroscopic measurements indicate that BA reacts with isopropyl alcohol with a rate constant some five times slower than the diffusion limit (Table 7). This, in conjunction with the picosecond timescale measurements, gives a value for ksr. The absence of ether formation from the sensitized irradiation, when combined with the measured rate constant for reaction of 3BA with isopropyl alcohol, gives an upper limit for k-. These values give Keq and thus AGST 2 5.2 kcal mol-1 (Table 8). [Pg.337]

In the presence of a chiral promoter, the asymmetric aldol reaction of pro-chiral silyl enol ethers 71 with prochiral aldehydes will also be possible (Table 3-6). In this section, a chiral promoter, a combination of chiral diamine-coordinated tin(II) triflate and tributyl fluoride, is introduced. In fact, this is the first successful example of the asymmetric reactions between prochiral silyl enol ethers and prochiral aldehyde using a chiral ligand as promoter. [Pg.156]

Dimethyl ether is produced from natural gas via combined reforming and downstream DME synthesis. Technical data for a typical DME plant are based on information provided by Haldor Topsoe (personal communication, October, 2002) (see Table 7.15). [Pg.218]

For monocyclic crown ethers the data presented in Table 4 and the stability constants for glymes [43]—[46] determined by Chaput et al. (1975) can be combined to calculate the macrocyclic effect (Table 7). The data indicate that the gain in binding energy on ring closure shows the same pattern as the ion selectivity of the crown ether, being highest for Na+/15-crown-5, K+/18-... [Pg.292]


See other pages where Ether combination table is mentioned: [Pg.988]    [Pg.988]    [Pg.988]    [Pg.271]    [Pg.454]    [Pg.205]    [Pg.118]    [Pg.6]    [Pg.42]    [Pg.40]    [Pg.290]    [Pg.753]    [Pg.885]    [Pg.911]    [Pg.929]    [Pg.486]    [Pg.539]    [Pg.180]    [Pg.202]    [Pg.79]    [Pg.180]    [Pg.380]    [Pg.192]    [Pg.8]    [Pg.34]    [Pg.57]    [Pg.102]    [Pg.135]    [Pg.393]    [Pg.54]    [Pg.551]    [Pg.404]    [Pg.69]    [Pg.71]    [Pg.10]   
See also in sourсe #XX -- [ Pg.145 ]




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Combination table

Ethers Table

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