| 摘要 |
PURPOSE:To measure the existance ratio of <13>CO2 with high accuracy by diluting a sample gas of breath gas, etc. with N2 gas and by performing the measurement while keeping a constant CO2 density at all times. CONSTITUTION:A breath gas is passed to a mixing and buffer tank 3 with a proper carrier gas through a sample gas introducing part 1. On the other hand N2 gas is passed to the tank 3 by N2 gas for dilution introducing part 2 connecting to a N2 bomb and dilutes the breath gas. A flow controller 4 for controlling the volume of N2 gas being introduced to the tank 3 is provided at the N2 gas introducing part 2 and the breath gas diluted by N2 gas in the tank 3 is led to the main body cell of a <13>CO2 analyzer 5, and thereupon the absorption of <13>CO2 and <12>CO2 is measured, and the ratio of <13>CO2/<12>CO2 and the existance ratio of <13>CO2 are found. |
