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  • ISO 2465-1974 - 中外标准 - - 1974/9 - 废止
    The method is applicable tp products with a content greater than 0,1 mg/kg. It is applied to a test portion as it is, and to another identical portion with a known quantity of arsenic added. The principle consists in reduction of the arsenic by zinc in a hydrochloric acid medium, with the formation of arsine; absorption of the arsine in a solution of silver diethyldithiocarbamate in pyridine. Photometric measurement of the purplish-red colour produced by the colloidally dispersed silver at the maximum of the absorption curve at a wavelength of about 540 nm.
  • ISO 2750-1974 - 中外标准 - - 1974/8 - 废止
    Lays down the principle of the visual comparison of the colour of a solution of the sample in formaldehyde, stabilized at a pH of 10 0.1, with that of colour standards. Expression of the results in terms of Hazen units. For routine control purposes, referring to ISO 2211. The method has also been approved by the IUPAC.
  • CNS 3717-1974 - 中外标准 - - 1974/6 - 现行
    六氯苯检验
  • CNS 3718-1974 - 中外标准 - - 1974/6 - 现行
    丁烷工业的
  • CNS 3716-1974 - 中外标准 - - 1974/6 - 现行
  • ISO 2499-1974 - 中外标准 - - 1974/5 - 废止
    Specifies the sampling, the determination of distillation characteristics, of the density at 20 0C, of residue on evaporation on a water bath, of the water content, of alcoholic impurities, of the acidity to phenolphthalein and the measurement of colour.
  • ISO 2501-1974 - 中外标准 - - 1974/5 - 废止
    Acetylation of a test portion with acetyl chloride and determination of the alcohol equivalent to the acetyl groups that have reacted by titration with standard volumetric sodium hydroxide solution in the presence of phenolphthalein. Correction of the acidity of the sample.
  • ISO 2527-1974 - 中外标准 - - 1974/4 - 废止
    The method is applicable to simple and mixed alcohol esters that are liquid at ambient temperature. The following principle is specified: Saponification of the ester using potassium hydroxide in ethanolic solution followed by titration with standard volumetric hydrochloric acid solution in the presence of phenolphthalein as indicator. In the case of mixed alcohol esters the relative molar mass of which can only be estimated the saponification and ester values are used to express the result.
  • ISO 2520-1974 - 中外标准 - - 1974/4 - 废止
    Specifies the sampling, the determination of the density at 20 0C, of the water content, of the acidity to phenol red, of apparent free phenols content and the measurement of colour in Hazen units.
  • ISO 2513-1974 - 中外标准 - - 1974/4 - 废止
    Prescribes that samples shall be taken in clean stainless steel flasks purged with nitrogen. The low boiling point at 20.2 0C makes difficult the determination of density at 20 0C, therefore, the determination is specified at 15 0C. The procedure is performed according to the method given in ISO 758.
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