An improved portable gas chromatograph for the measurement of nitrogen-fixing activity

An improved portable gas chromatograph using a gas sensor as a detector was constructed and its efficiency was tested for the measurement of nitrogen-fixing activity. The ethylene was quantitatively determined by this gas chromatograph at the same sensitivity as that of a conventional gas chromatograph using a flame ionization detector, when the amount of ethylene injected was less than 1.5 nmol. The equipment was found to be handy and inexpensive, and suitable for the measurement of acetylene reduction activity in the field.