Fruits, vegetables and derived products — Determination of nitrite and nitrate content — Molecular a...
The method consists in extracting a test portion with hot water, precipitating the protein by addition of solutions of potassium hexacyanoferrate(II) and zinc acetate, and filtrating the precipitate. Further, reduction of the nitrate to nitrite by metallic cadmium (only for determining the nitrate). Then addition of sulfanilamide chloride and N-(1-naphtyl)ethylenediamine and measurement of the…
Pipes and fittings of acrylonitrile/butadiene/styrene (ABS) — General specification for moulding and...
Specifies ABS-plastics for pipe applications, the properties chosen to designate
ABS plastics for pipes are: acrylonitrile content, Vicat softening temperature,
melt flow rate, impact strength and flexural modulus. Reference is made to ISO
2580.
Manganese ores and concentrates — Determination of manganese content — Potentiometric method
The method is applicable to the determination of a manganese content equal to or greater than 15 % (m/m). ISO 4298 should be read in conjunction with ISO 4297. Specifies principle, reactions, reagents, apparatus, sampling, procedure and expression of results.
Chromium ores and concentrates — Determination of silicon content — Molecular absorption spectrometr...
The molecular absorption spectrometric method (A) is applicable to products having silicon contents from 0,05 to 0,5 % (m/m), the gravimetric method (B) is applicable to products having silicon contents from 0,5 to 15 % (m/m). ISO 5997 should be read in conjunction with ISO 4297. Specifies among other things principle, reagents, apparatus, procedure, spectrometric measurement (method A only) and…
Crude sodium borates for industrial use — Determination of total and alkali-soluble calcium and magn...
A test solution is prepared by one of the two following ways: a) fusion of a test portion with sodium carbonate in the case of total calcium and magnesium contents, and b) from an aliquot portion of "solution A" (ISO 2217) for alkali-soluble calcium and magnesium contents. Lanthanum ions are added to the solution to suppress certain interferences. The solution is aspirated into an…
