Skip to main content

Nitric Oxide Isotopic Analyzer Based on a Compact Dual-Modulation Faraday Rotation Spectrometer

Author(s): Zhang, Eric; Huang, Stacey; Ji, Qixing; Silvernagel, Michael; Wang, Yin; et al

To refer to this page use:
Abstract: We have developed a transportable spectroscopic nitrogen isotopic analyzer. The spectrometer is based on dual-modulation Faraday rotation spectroscopy of nitric oxide isotopologues with near shot-noise limited performance and baseline-free operation. Noise analysis indicates minor isotope (15NO) detection sensitivity of 0.36 ppbv·Hz−1/2, corresponding to noise-equivalent Faraday rotation angle (NEA) of 1.31 × 10−8 rad·Hz−1/2 and noise-equivalent absorbance (αL)min of 6.27 × 10−8 Hz−1/2. White-noise limited performance at 2.8× the shot-noise limit is observed up to ~1000 s, allowing reliable calibration and sample measurement within the drift-free interval of the spectrometer. Integration with wet-chemistry based on acidic vanadium(III) enables conversion of aqueous nitrate/nitrite samples to gaseous NO for total nitrogen isotope analysis. Isotopic ratiometry is accomplished via time-multiplexed measurements of two NO isotope transitions. For 5 μmol potassium nitrate samples, the instrument consistently yields ratiometric precision below 0.3‰, thus demonstrating potential as an in situ diagnostic tool for environmental nitrogen cycle studies.
Publication Date: Oct-2015
Electronic Publication Date: 14-Oct-2015
Citation: Zhang, Eric, Huang, Stacey, Ji, Qixing, Silvernagel, Michael, Wang, Yin, Ward, Bess, Sigman, Daniel, Wysocki, Gerard. (2015). Nitric Oxide Isotopic Analyzer Based on a Compact Dual-Modulation Faraday Rotation Spectrometer. Sensors, 15 (10), 25992 - 26008. doi:10.3390/s151025992
DOI: doi:10.3390/s151025992
EISSN: 1424-8220
Pages: 25992 - 26008
Type of Material: Journal Article
Journal/Proceeding Title: Sensors
Version: Final published version. This is an open access article.

Items in OAR@Princeton are protected by copyright, with all rights reserved, unless otherwise indicated.