BS 7164-21(1990) : 1990被替代

Describes a macro-method and semi-micro method for determining nitrogen content in raw natural rubber and natural rubber latex using variants of the Kjeldahl process. Covers normative references, principle, macro-method, semi-micro method and test report. Figures explain the assembly of digestion apparatus for the semi-micro method, exhaust tube for the semi-micro method, digestion flasks for the semi-micro method, assembly of distillation apparatus for the semi-micro method, distillation flask for the semi-micro method, trap for the semi-micro method, condenser jacket for the semi-micro method, drip funnel for the semi-micro method and condenser tube for the semi-micro method.

BS 1673-2(1967) : 1967

BS 903-B11&12(1960) : 1960

BS 7164-21(1996) : 1996

ISO 1656 : 2014 - Identical