Abstract
Two-tone frequency modulation spectroscopy (TTFMS) is applied to the determination of water activity using an 820-nm GaAlAs diode laser. By measuring the relative light absorption of water vapor over a solution and over a pure water reference, the water activity in the solution is determined. Fast, nonintrusive, and selective measurements are demonstrated. The detection limit for measuring a relative water vapor pressure change was 0.3%. The application of laser modulation spectroscopy to the determination Of water activity is discussed, and suggestions on increasing the sensitivity and accuracy are presented.
Full Text 
Sign-in/Register to access full text options
Sign-in/Register to access full text options 
Paper version not known
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
