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Glavni meni

ISO 5438:1993

Acid-grade and ceramic-grade fluorspar — Determination of silica content — Reduced-molybdosilicate spectrometric method
18. 3. 1993.
95.99   Povučen   3. 3. 2010.

Опште информације

95.99     3. 3. 2010.

ISO

ISO/TC 175

Međunarodni standard

73.080  

francuski   engleski  

Kupovina

Povučen

Jezik na kome želite da primite dokument.

Apstrakt

The method specified is based on decomposition of a test portion by fusion with sodium carbonate and subsequent acidification with hydrochloric acid in the presence of boric acid to complex fluoride, formation of the molybdosilicic acid complex and selective reduction to the blue molybdosilicic acid complex with addition of tartaric acid to prevent interference from phosphate, spectrometric measurement of the absorbance of the coloured complex at the wavelength of maximum absorption (about 795 nm). Applies to products having silica contents, expressed as SiO2, in the range 0,05 % (m/m) to 4,0 % (m/m).

Životni ciklus

PRETHODNO

POVUČEN
ISO 5438:1985

TRENUTNO

POVUČEN
ISO 5438:1993
95.99 Povučen
3. 3. 2010.