Fertilizers — Determination of total nitrogen content — Titrimetric method after distillation
The method consists in reducing of nitrate to ammonia by chromium powder in acid medium, converting of organic and urea nitrogen into ammonium sulfate by digestion with concentrated sulfuric acid in the presence of a catalyst, distilling of the ammonia from an alkaline solution and absorbing in an excess of standard volumetric sodium hydroxide solution. The method is not recommended for materials…
Copper and copper alloys — Determination of phosphorus content — Molybdovanadate spectrometric metho...
The method is applicable to the determination of phosphorus contents between 0.000 5 and 0.5 % (m/m). ISO 4741 specifies principle, reagents, apparatus, procedure, expression of results and test report.
Copper and copper alloys — Determination of chromium content — Flame atomic absorption spectrometric...
The method is applicable to the determination of chromium contents between 0.003 and 2.0 % (m/m). ISO 4744 specifies principle, reagents, apparatus, sampling, procedure, expression of results and test report. An International Standard dealing with the sampling of copper and copper alloys is in preparation.
Manganese ores — Sampling — Part 1: Increment sampling
Specifies methods for taking samples of manganese ores to be used at the places of dispatch and acceptance of ores for determining the chemical composition and moisture content of a consignment.The methods are applicable to both the manual and mechanical sampling of natural or processed ores. Details of the hammer and shovel method are given in the annex.
Cheese and processed cheese products — Determination of total phosphorus content — Molecular absorpt...
Describes a procedure which includes the digestion of cheese by sulphuric acid and hydrogen peroxide, the addition of molybdate-ascorbic acid solution to form molybdenum blue, and the molecular absorption spectrometric measurement of the blue colour formed. Instead of wet digestion it is also possible to use dry ashing provided that the same results are given by the procedure.
The method is applicable to products of cadmium-containing copper alloys listed in International Standards having cadmium contents between 0,0005 and 2,0 % (m/m). Specifies principle, reagents, apparatus, sampling, procedure, expression of results and test report.
Milk — Determination of protein content — Amido black dye-binding method (Routine method)
Is applicable to raw or thermally or mechanically processed whole milk, partly skimmed and skimmed milk provided that the samples are in good condition. In some cases it can also be applied to preserved samples. The principle of determination consists in adding amido black solution to a test portion resulting in the formation of an insoluble dye-protein complex which is removed by centrifuging or…
Water quality — Determination of calcium content — EDTA titrimetric method
Describes a procedure for ground waters, surface waters and drinking waters. It can also be used for municipal and industrial raw waters, provided they do not contain interfering amounts of heavy metals. The procedure is not applicable to sea waters and other similar waters having a high concentration of salts. It is applicable to waters with contents ranging from 2 to 100 mg/l. For higher…
Copper alloys — Determination of chromium content — Titrimetric method
The method is used for the determination of the total chromium content of copper-chromium alloys listed in International Standards. It is applicable to products having chromium contents between 0,10 and 2,0 % (m/m). Specifies principle, reagents, apparatus, procedure, expression of results and test report.
