Formaldehyde vapor produced from hexamethylenetetramine and pesticide: Simultaneous monitoring of formaldehyde and ozone in chamber experiments by flow-based hybrid micro-gas analyzer

Measurement Device for Ambient Carbonyl Sulfide by Means of Catalytic Reduction Followed by Wet Scrubbing/Fluorescence Detection

“… a The same device as in ref ( 53 ) was fabricated and examined in this study. b Gas channels of the PVC devices were honeycomb-patterned, same as the liquid channel.…”

“…We have previously developed a microchannel scrubber to collect water-soluble analyte gases. − Fabrication of microchannels is advantageous for gas scrubbing. Similar approaches have been carried out by Guglielmino et al for absorbance detection and Ueda et al and Becker et al for fluorescence detection of gaseous HCHO. − An effective enrichment of the analyte gas was achieved by the microchannel scrubber, which could have a high ratio of the gas absorbing area to absorbing solution volume, and a small liquid volume of the scrubber makes the system response faster.…”

“… a The same device as in ref was fabricated and examined in this study. b Gas channels of the PVC devices were honeycomb-patterned, same as the liquid channel. See Figure S2 for the design of the three scrubbers. c T90% up and down is 90% response time when the H 2 S concentration was changed from 0 to 50 ppbv and from 50 to 0 ppbv, respectively. …”

“…The produced H 2 S can be analyzed by wet scrubbing, followed by fluorescence detection, as previously demonstrated. 47 , 48 The microsystem for H 2 S, called micro-gas analysis system (μGAS), 49 , 50 is a highly sensitive portable device and could be applied for the measurement of CH 3 SH, 51 HCHO, 52 , 53 and breath NO 54 for environmental and medical applications. 55 , 56 However, fabrication of the microchannel scrubber, which is the key device of the μGAS, can be carried out only by skilled personnel.…”

“…We have found that the conventional alumina catalyst works well for this purpose at a low temperature (<100 °C) with a long lifetime. The produced H 2 S can be analyzed by wet scrubbing, followed by fluorescence detection, as previously demonstrated. , The microsystem for H 2 S, called micro-gas analysis system (μGAS), , is a highly sensitive portable device and could be applied for the measurement of CH 3 SH, HCHO, , and breath NO for environmental and medical applications. , However, fabrication of the microchannel scrubber, which is the key device of the μGAS, can be carried out only by skilled personnel. In this work, the channel scrubber was re-examined to make fabrication easier and the device more robust and maintaining the performance to establish a catalytic hydrolysis-miniature gas analysis system (CH-mGAS).…”