DIFFUSION SOURCE OF GAS MICROFLOW (VARIANTS) Russian patent published in 1998 - IPC

FIELD: physical and chemical methods and analysis. SUBSTANCE: microflow gas source is designed to produce microflows of gases with known microconcentration of volatile substances. Increase in specific gas permeability of walls of source diffusion assembly is obtained due to reduction of capillary thickness, increase in temperature stability of source efficiency and removal of direct contact of gas-diluent with gas-permeable surface of source diffusion assembly. To this end, diffusion assembly of source secured to gas-impermeable body of source tightly is made as stopped up capillary arranged in source body. According to the first variant, capillary is flat, its walls touch each other with their internal surfaces. According to the second one, internal surface of capillary is filled with gas-permeable material. Internal surface of capillary may have microchannels oriented along its generatrix. These channels reduce pneumatic resistance to dosed gas flow. EFFECT: higher results of analysis. 4 cl, 3 dwg