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The essential oil is subjected to cold formylation by a mixture of formic acid and acetic anhydride. After formylation the ester value is determined. The free alcohols content is calculated taking into account the ester values of the same oil before formylation. Total alcohols and combined alcohols content can also be determined with this method.

Specifies a potentiometric method using a fluoride-ion sensitive electrode. After destillation of fluorine from the test portion in the presence of perchloric acid the distillate shall be titrated with lanthane nitrate solution. Applicable to products having a calcium fluoride content greater than 90 %.

The method consists in homogenizing the product, followed by quantitative entraining, by steam, of the acid present in a test portion, determination of the acid in the destillate obtained, either by spectrophotometry in the ultra-violet range (technique A) or by measuring by photocolorimetry or by spectrophotometry the pink colour obtained after oxidation by chromic acid and then treatment with…

Applicable to products having As content equal or more than 0.2 mg/kg. Dissolution of a test portion, acidification with hydrochloric acid solution and oxidation with potassium bromide-bromate solution, followed by hydrolysis. Determination in accordance with the general method in ISO 2590, clause 3. Has also been approved by the IUPAC.

The method is applicable to carbide and binder metal powder mixtures, free of lubricant, and all grades of presintered or sintered hardmetals, with a titanium content exceeding 0,2 % (m/m). Specifies principle, interfering elements, reagents, apparatus, sample preparation, procedure, elimination of interferences, preparation of the calibration curve, expression of results and test report.