Potassium sodium tungstate

Tetrahydrobenzyl alcohol (( )3-cyclohexenene-l-methanol) and 30% aqueous hydrogen peroxide were purchased from Fluka, AG. 3-Cyclohexene-1-carboxylic acid and cis-4-cyclohexene-l,2-dicarboxylic acid were used as purchased from Lancaster Chemical Co. Methyl iodide, acetic anhydride, Oxone (potassium peroxymonosulfate), Aliquot 336 (methyl tri-n-octylammonium chloride), sodium tungstate dihydrate and N,N-dimethylaminopyridine (DMAP) were purchased from Aldrich Chemical Co. and used as received. 3,4-Epoxycyclohexylmethyl 3, 4 -epoxycyclohexane carboxylate (ERL 4221) and 4-vinylcyclohexene dioxide were used as purchased from the Union Carbide Corp. (4-n-Octyloxyphenyl)phenyliodonium hexafluoroantimonate used as a photoinitiator was prepared by a procedure described previously (4). 

OLEFINS N,N-Dimethylformamide dimethyl acetal. Iron pentacarbonyl. 0-4-Methylphenyl chlorothioformate. Naphthalene-Sodium. Potassium hexachloro-tungstate. Sodium methylsulflnylmetbyl-ide. Sodium sulfide. p-Tolucnesulfonyl-hydrazine. Trimethyl phosphite. Ttiphen-ylphosphine. 

A hydrosol of tungsten hydroxide is readily produced by the electrolysis of a 2 per cent, solution of sodium tungstate between a mercuiy cathode and a silver anode in a Hildebrand cell. The solution must not be allow ed to become acid, or blue compounds are produced. The hydrosols obtained in this way are clear and transj arent but brown in colour. The addition of potassium chloride causes coagulation, a black powder, resembling the lower oxides of tungsten, being formed. ... 

Sodium Tungstates.—The anhydrous normal tungstate, NajWOi, is prepared by the fusion method described for potassium tungstate (see p. 222), or by complete dehydration of the hydrates at 100° C. or over sulphuric acid. It may be obtained from the mineral wolframite by fusion with alkali as already described (see p. 202). 

C for 1 h. A solution of 1 M sodium tungstate (50 mL, 50 mmol) and, immediately thereafter, 80 mL of 4M HCl are added. After cooling to room temperature, the solution is filtered through a fine frit if it is not completely clear. Its volume is 450 to 500mL. This solution is used to obtain either the acid or the potassium salt. 

To the boiling Solution B, a solution of 4M HCl (165 mL) is added drop by drop over 5 min with vigorous stirring in order to dissolve the local precipitate of tungstic acid. Then solution A is added, followed quickly by addition of 50 mL of 4 M HCl. The pH is 5 to 6. The solution is kept at 100 °C for 1 h. A solution of 1 M sodium tungstate (50 mL, 50 mmol) and, immediately thereafter, 80 mL of 4 M HCl are added. After cooling to room temperature, the solution is filtered through a fine frit if it is not completely clear. Its volume is <> 450 to 500 mL. This solution is used to obtain either the acid or the potassium salt. 

Lead zirconate titanate (PZT), barium titanate (BaTiOs), lead titanate (PbTiOs), potassium niobate (KNbOa), lithium niobate (LiNbOs), lithium titanate (LiTaOs), sodium tungstate (Na2W03) and zinc oxide (ZnO) are some of the most typical piezoceramics. Of these, PZT is the most widely used due to its superior performance. However, the toxicity of lead has raised concerns over the use of PZT. A restriction on the amount of lead present has been placed and is focused at eliminating its use eventually. Nevertheless, PZT has no rival at present. 

Sal soda, see Sodium carbonate 10-water Saltpeter, see Potassium nitrate Scacchite, see Manganese chloride Scheelite, see Calcium tungstate(VI)(2—)... 

Elsewhere, in a series of Japanese patents, mixtures of resorcinol + sodium nitrate, glycerine + sodium nitrate, lithium hydroxide + tungstate, etc., have been claimed to be effective. An example of the use of inhibited cooling mixtures of low toxicity is provided by a patent which describes a mixture of silicate-I- polyphosphate -I- a saccharide, e.g. sucrose or fructose, as the inhibitor formulation in a propylene glycol -I- potassium-hydrogen-carbonate mixture used in aluminium cooler boxes for ice-cream. 

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