State system for ensuring the uniformity of measurements. State primary standard and all-union verification schedule for means measuring mass flow of gas within the range of 4x10 in minus 2 degree up to 2,5x10 in 2 degree kg/sec
State system for ensuring the uniformity of measurements. Reflectometers of the extreme ultraviolet radiation for measurements of the characteristics of multilayer nanostructures in the wavelength range 10 to 30 nm. Procedure of measurements