A compact, lightweight gas standards generator for permeation tubes
نویسندگان
چکیده
A lightweight, compact gas standards generator for permeation tubes is described. This system provides reliable temperature control during periods of intermittent power and is ideal for field measurements. A eutectic alloy with a high heat of fusion is used as a phase change material. This thermal source allows the system to maintain a constant permeation tube temperature of 46.6 °C for over 5 h in the absence of external power. This permeation system is currently being used in an aircraft chemical ionization mass spectrometer to provide HNO3 calibration. © 2003 American Institute of Physics. @DOI: 10.1063/1.1570949#
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