{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,23]],"date-time":"2026-06-23T17:44:22Z","timestamp":1782236662099,"version":"3.54.5"},"reference-count":52,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2016,7,25]],"date-time":"2016-07-25T00:00:00Z","timestamp":1469404800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We address the sensitive detection and discrimination of gases impacting the environment, such as CH4, NH3, SO2, and CO, using a sensor array and aided by principal component analysis (PCA). A 32-element chemiresistive sensor array consisting of nine different sensor materials including seven types of modified single-walled carbon nanotubes and two types of polymers has been constructed. PCA results demonstrate excellent discriminating ability of the chemiresistor sensor chip in the 1\u201330 ppm concentration range. The accuracy of the sensor was verified against data collected using cavity ring down spectroscopy. The sensor chip has also been integrated with a smartphone and has been shown to reproduce the sensing performance obtained with the laboratory measurement system.<\/jats:p>","DOI":"10.3390\/s16081163","type":"journal-article","created":{"date-parts":[[2016,7,25]],"date-time":"2016-07-25T10:04:26Z","timestamp":1469441066000},"page":"1163","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":63,"title":["A Sensor Array for the Detection and Discrimination of Methane and Other Environmental Pollutant Gases"],"prefix":"10.3390","volume":"16","author":[{"given":"Ami","family":"Hannon","sequence":"first","affiliation":[{"name":"NASA Ames Research Center, Moffett Field, CA 94035, USA"},{"name":"Analtyical Mechanics Associates, Inc. at NASA Ames Research Center, Moffett Field, CA 94035, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yijiang","family":"Lu","sequence":"additional","affiliation":[{"name":"NASA Ames Research Center, Moffett Field, CA 94035, USA"},{"name":"ELORET Corporation at NASA Ames Research Center, Moffett Field, CA 94035, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jing","family":"Li","sequence":"additional","affiliation":[{"name":"NASA Ames Research Center, Moffett Field, CA 94035, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M.","family":"Meyyappan","sequence":"additional","affiliation":[{"name":"NASA Ames Research Center, Moffett Field, CA 94035, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2016,7,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1502","DOI":"10.1021\/ac60191a001","article-title":"A New Detector for Gaseous Components Using Semiconductor Thin Film","volume":"34","author":"Seiyama","year":"1962","journal-title":"Anal. 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