Calcium methanol-water system

Curve-fitting computation technique was applied for the calculation of formation constants of calcium lactate in methanol-water, ethanol-water, and glucose-water systems (60) with excellent results. In the calculation of the average formation constant Kav( = (Ki K2)i), P turned out to be about 190 for the methanol-water system, 192 for the ethanol-water system, and 185 for the glucose-water system. The value of b was 204. 

A suspected water gel is examined on a microscope slide to identify the microspheres used in slurry and emulsion explosives. The gel is directly extracted with methanol, which dissolves the amine salt, and a small amount of NH4NO3. TLC on a cellulose plate using a chloroform-methanol-water system separates the sensitizers. The plate is sprayed with ni-nhydrin and heated to visualize the amine salt. A second spray with diphenylamine in ethanol followed by long-wave UV irradiation visualizes the NFi4N03 if desired. Alternatively, the methanol extract may be evaporated to near dryness, redissolved in water, and analyzed by IC to identify the sensitizer. An intact sample can also be extracted with water using either a small homogenizer or ultrasonic agitation to disrupt the gel structure. Microspheres float on the surface and are removed for examination by SEM-EDX to characterize the manufacturer. Spot tests and IC identify ammonium, calcium, and nitrate ions in the water extract. Flake aluminum, if present, is identified as described above. 

The lower, chloroform-rich phase is separated carefully from the protein-containing interface, and then it is washed twice with methanol-water (10 9, v/v) and the washes are discarded. The chloroform layer contains the phosphatidic acid (as a sodium salt) and can be isolated by acetone precipitation. The yields can be of the order of 90-95%. One alternative route to identification of the chloroform-soluble material is to analyze it for total phosphorus and total fatty acid ester (see procedures described earlier). In the case of diacylphosphatidylcholine as the substrate, the fatty acid ester/P molar ratio should be 2.0. Another approach is to subject the chloroform-soluble fraction to preparative thin-layer chromatography on silica gel H (calcium ion free) in a two-dimensional system with a solvent system of chloroform-methanol-28% ammonium hydroxide (65 35 6, v/v) in the first direction and a solvent system of chloroform-acetone-methanol-glacial acetic acid-water (4.5 2 1 1.3 0.5, v/v) in the second direction. The phosphatidic acid will not migrate far in the basic solvent Rf 0.10) and will show an Rf value one-half of that of any remaining starting substrate (fyO.40) in the second solvent. Of course with a simple substrate system, one can use the basic solvent in one dimension only... 

Chitin sheets are excellent for use in biomedical devices due to their biodegradability and lack of toxicity. These sheets can be prepared by simple procedures. A solution of a-chitin, in saturated calcium chloride dihydrate-methanol solvent system, is dropped into excess of distilled water with gentle mixing to desolubilize the ot-chitin the obtained chitin hydrogel is decanted several times with distilled water and filtered. ot-Chitin sheets are obtained after the evaporation of water. 

The homogeneity of glycolipids separated by the various procedures already described should be determined by thin-layer chromatography or HPTLC in several solvent systems. Mixtures of chloroform/methanol/water in different ratios, such as 60 35 8 v/v or 55 45 10 v/v as well as those with added calcium (chloroform/methanol/0.02% CaCl2.2H20, 60 40 9 v/v) or ammonia (chloroform/methanol/15M ammonia/water 60 35 1 7 v/v ) are particularly useful for the separation of gangliosides.Neutral and acetylated glycolipids are separated by chloroform/methanol/water (60 25 4 v/v) and 1,2-dichloromethane (DCE)/methanol/water (88 12 0.1 v/v) respectively. 

Monosilicic acid can be prepared from the silicate-acid system, just as from the silicon tetrachloride-water or methyl orthosilicate-water systems [746]. Acetic acid or resin exchangers in the H-form can be added to dilute solutions of sodium silicate. Monosilicic acid is formed by reaction of solid calcium orthosilicate with hydrogen chloride in methanol, according to the equation ... 

The equihbrium shown in equation 3 normally ties far to the left. Usually the water formed is removed by azeotropic distillation with excess alcohol or a suitable azeotroping solvent such as benzene, toluene, or various petroleum distillate fractions. The procedure used depends on the specific ester desired. Preparation of methyl borate and ethyl borate is compHcated by the formation of low boiling azeotropes (Table 1) which are the lowest boiling constituents in these systems. Consequently, the ester—alcohol azeotrope must be prepared and then separated in another step. Some of the methods that have been used to separate methyl borate from the azeotrope are extraction with sulfuric acid and distillation of the enriched phase (18), treatment with calcium chloride or lithium chloride (19,20), washing with a hydrocarbon and distillation (21), fractional distillation at 709 kPa (7 atmospheres) (22), and addition of a third component that will form a low boiling methanol azeotrope (23). 

Isomerization processes produce sour water and caustic wastewater. The ether manufacturing process utilizes a water wash to extract methanol or ethanol from the reactor effluent stream. After the alcohol is separated, this water is recycled back to the system and is not released. In those cases where chloride catalyst activation agents are added, a caustic wash is used to neutralize any entrained hydrogen chloride. This process generates a caustic wash water that must be treated before being released. This process also produces a calcium chloride neutralization sludge that must be disposed of off-site. 

Table IV also includes some values determined in methanol as the solvent these are very much higher (and, hence, also more accurate) than those in water, because the polyol competes with methanol, rather than with water, for outer-sphere positions on the cation. These figures explain why carbohydrates are soluble in methanol or ethanol containing high concentrations of calcium chloride, or even potassium acetate, and in such systems as lithium chloride in 2-methoxyethanol. ° Sugar derivatives that are soluble in non-hydroxylic solvents form complexes with cations in those solvents even more readily for example, methyl 2,3-0-isopropylidene-4-0-methyl-) -L-rhamnopyranoside (24) (but not its a anomer) will form a complex with sodium iodide in acetone, the Na" " ion coordinating to 0-1,0-2, and 0-3. In aqueous solution, the concentration of this complex would be negligible.

Reaction kinetics using radiolabeled DKP were carried out as follows Crude enzyme was incubated at 30°C with 25 mM DKP (1.2 )iCi [ C-Phe]-DKP) in 25 mM phosphate buffer, pH 8.0, with and without 5.0 mM EGTA in a total volume of 0.1 mL. Aliquots (10 pL) were removed over time, spotted on silica TLC plates and developed with the following solvent system chloroform methanol ethanol water formic acid (10 4 4 2 1) with visualization using alkaline fluorescamine (0.5 mg/mL in 50 50 acetonitrile water) and Kl/starch after exposure to calcium hypochlorite vapor. The TLC plates were scraped in 1 cm bands and radioactivity determined by scintillation counting using a Beckman LS-3801 counter. 

IR spectroscopic studies were conducted of the reaction of polyacrylic acid(PAA) and metal oxides (zinc oxide, calcium oxide, cupric oxide, chromium oxide and aluminium oxide). Factors such as the amount of metal oxide, reaction time, solvents, type of metal oxides and temp, were also evaluated to derive the optimum conditions for this reaction. The reactions of chromium oxide and aluminium oxide were far from complete. An extra solvent added to the reaction system could increase the solubility of PAA and metal oxide in the solution to cause complete reaction. The reactivity of the reaction was increased by using a hydrophilic solvent, particularly water and methanol. Furthermore, the reaction rate increased when temp, decreased. The reactivity of the reaction was proportional to the pH value of the metal oxide in the aqueous solution. 16 refs. 

A reverse microemulsion synthesis of CaCOa was reported later by Roman et al [339] who used xylene, a diluent oil (100-150 NS grade), 70% active sulfonic acid, calcium hydroxide and methanol the water content was evidently very small. Carbon dioxide was bubbled through the system the conversion was almost total within 0.5h. Water and methanol were separated by distillation. The particle size of the carbonates was around 1.5-3.0 nm. 

Hasegawa et al (1995) developed a new cementitious material by combining calcium aluminate cement with a methanolic solution of a phenol resin precursor. The water-free mix must be processed by high-shear mixing in a twin-roller mill in a way similar to that used in the production of MDF materials. The rheology of the resin-cement paste may be improved by adding to the system small amounts of a modifier such as alcohol-soluble polyamide and a plasticizer. A typical mix proportion is as follows ... 

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