PROCEDURE MEASURING SPECIFIC SURFACE OF DISPERSIVE AND POROUS MATERIALS

FIELD: analytical instrumentation engineering, design of measuring devices. SUBSTANCE: procedure includes positioning of tested specimen into space blown out by stationary stream of gas mixture containing gas- adsorbate under atmospheric pressure. Inert gas with boiling point exceeding boiling point of liquid nitrogen is used in the capacity of gas adsorbate and helium is employed as gas carrier. Space with specimen is cooled to temperature of liquid nitrogen and is kept at this temperature till dynamic equilibrium between gas and adsorption phases is established. After this specimen is heated and concentration of gas-adsorbate is measured. Salient feature of procedure lies in that free portion of space with tested specimen is filled with insert made of material with low common surface and low thermal conductivity, for instance, glass or fluoroplastic. EFFECT: increased measurement precision, enlarged range of measured specific surfaces. 2 cl, 5 dwg