skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Rapid and sensitive quantification of isotopic mixtures using a rapidly-swept external cavity quantum cascade laser

Abstract

A rapidly-swept external-cavity quantum cascade laser with an open-path Herriott cell is used to quantify gas-phase chemical mixtures of D 2O and HDO at a rate of 40 Hz (25-ms measurement time). The chemical mixtures were generated by evaporating D 2O liquid near the open-path Herriott cell, allowing the H/D exchange reaction with ambient H 2O to produce HDO. Fluctuations in the ratio of D 2O and HDO on timescales of <1 s due to the combined effects of plume transport and the H/D exchange chemical reaction are observed. Noise-equivalent concentrations (1σ) (NEC) of 147.0 ppbv and 151.6 ppbv in a 25-ms measurement time are determined for D 2O and HDO, respectively, with a 127-m optical path. These NECs are improved to 23.0 and 24.0 ppbv with a 1-s averaging time for D 2O and HDO, respectively. NECs <200 ppbv are also estimated for N2O, 1,1,1,2–tetrafluoroethane (F134A), CH 4, acetone and SO 2 for a 25-ms measurement time. Finally, the isotopic precision for measurement of the [D 2O]/[HDO] concentration ratio of 33‰ and 5‰ is calculated for the current experimental conditions for measurement times of 25 ms and 1 s, respectively.

Authors:
 [1];  [1];  [1]
  1. Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Optical Sensing
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA), Office of Nonproliferation and Verification Research and Development (NA-22)
OSTI Identifier:
1330581
Report Number(s):
PNNL-SA-117042
Journal ID: ISSN 2304-6732; PII: photonics3020033
Grant/Contract Number:  
AC05-76RL01830
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Photonics
Additional Journal Information:
Journal Volume: 3; Journal Issue: 2; Journal ID: ISSN 2304-6732
Publisher:
MDPI
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; external cavity quantum cascade laser; infrared spectroscopy; trace-gas sensing

Citation Formats

Brumfield, Brian E., Taubman, Matthew S., and Phillips, Mark C. Rapid and sensitive quantification of isotopic mixtures using a rapidly-swept external cavity quantum cascade laser. United States: N. p., 2016. Web. doi:10.3390/photonics3020033.
Brumfield, Brian E., Taubman, Matthew S., & Phillips, Mark C. Rapid and sensitive quantification of isotopic mixtures using a rapidly-swept external cavity quantum cascade laser. United States. doi:10.3390/photonics3020033.
Brumfield, Brian E., Taubman, Matthew S., and Phillips, Mark C. Mon . "Rapid and sensitive quantification of isotopic mixtures using a rapidly-swept external cavity quantum cascade laser". United States. doi:10.3390/photonics3020033. https://www.osti.gov/servlets/purl/1330581.
@article{osti_1330581,
title = {Rapid and sensitive quantification of isotopic mixtures using a rapidly-swept external cavity quantum cascade laser},
author = {Brumfield, Brian E. and Taubman, Matthew S. and Phillips, Mark C.},
abstractNote = {A rapidly-swept external-cavity quantum cascade laser with an open-path Herriott cell is used to quantify gas-phase chemical mixtures of D2O and HDO at a rate of 40 Hz (25-ms measurement time). The chemical mixtures were generated by evaporating D2O liquid near the open-path Herriott cell, allowing the H/D exchange reaction with ambient H2O to produce HDO. Fluctuations in the ratio of D2O and HDO on timescales of <1 s due to the combined effects of plume transport and the H/D exchange chemical reaction are observed. Noise-equivalent concentrations (1σ) (NEC) of 147.0 ppbv and 151.6 ppbv in a 25-ms measurement time are determined for D2O and HDO, respectively, with a 127-m optical path. These NECs are improved to 23.0 and 24.0 ppbv with a 1-s averaging time for D2O and HDO, respectively. NECs <200 ppbv are also estimated for N2O, 1,1,1,2–tetrafluoroethane (F134A), CH4, acetone and SO2 for a 25-ms measurement time. Finally, the isotopic precision for measurement of the [D2O]/[HDO] concentration ratio of 33‰ and 5‰ is calculated for the current experimental conditions for measurement times of 25 ms and 1 s, respectively.},
doi = {10.3390/photonics3020033},
journal = {Photonics},
issn = {2304-6732},
number = 2,
volume = 3,
place = {United States},
year = {2016},
month = {5}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Save / Share: