Abstract
A novel photothermal detector is described, based on a closed cell suitable for use with low-frequency modulated continuous-wave light sources. Photothermal expansion in aqueous samples caused the deflection of a water meniscus held across a radius pinhole. Displacement of the water meniscus was measured using fibre-optic interferometry. A mercury discharge lamp (254 nm) and a laser diode (678 nm) were used to detect absorption by 2 ppb anthracene and 0.5 ppm potassium permanganate in aqueous solutions, respectively. The technique was used to detect differences between absorption coefficients in aqueous solutions down to approximately 20% of the background absorption of the water itself.
Sign-in/Register to access full text options 
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 callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
