State system for ensuring the uniformity of measurements. Certified reference materials of natural gas magistral and substitute natural gas. Procedure of determining the metrological characteristics
State system for ensuring the uniformity of measurements. Moist methane. Thermodynamic properties at temperatures from 200 K to 400 K, pressures from 0,1 to 10 MPa and relative moisture from 0,2 to 1,0
State system for ensuring the uniformity of measurements. State verification schedule for instruments measuring the ratio error and phase displacement of a.c. power frequency voltage in the range from 0,1/V3 to 750/V3 kV
