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PubMed · 12194178

A wireless, remote query ammonia sensor.

Q Y Cai·M K Jain·C A Grimes
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Abstract

This paper presents a wireless, remote query ammonia sensor comprised of a free-standing magnetoelastic thick-film coated with a polymer, poly(acrylic acid-co-isooctylacrylate), that changes mass in response to atmospheric ammonia concentration. The mass of the polymer layer modulates the resonant frequency the ferromagnetic magnetoelastic substrate, hence by monitoring the frequency response of the sensor, atmospheric NH3 concentration can be determined remotely, without the need for physical connections to the sensor or specific alignment requirements. The effect of copolymer composition, polymer film thickness, and relative humidity level (RH) on the sensitivity of the sensor were investigated. The sensor linearly tracks ammonia concentration below 0.8 vol.%, and tracks higher concentrations logarithmically; within the linear calibration range, a 0.02 vol.% change in NH3 concentration can be detected.

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AcrylatesAmmoniaAtmosphereAutomationElasticityEnvironmental MonitoringEvaluation Studies as TopicHumidityMagneticsPolymersJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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Q Y Cai, M K Jain, C A Grimes. 2001-07-10. A wireless, remote query ammonia sensor.. https://doi.org/10.1016/s0925-4005(01)00766-3

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Acrylates↗
PubMed2007

The effect of finishing and polishing procedures on the surface roughness of composite resin materials.

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