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Title: Standoff Detection of Isotopes in a NH3 Chemical Plume

Abstract

We perform standoff detection of 14NH3 and 15NH3 at a 10 Hz rate in a chemical plume with varying concentration using an external cavity quantum cascade laser swept over the range 930-1065 cm-1.

Authors:
;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1361011
Report Number(s):
PNNL-SA-125922
DN2001000
DOE Contract Number:
AC05-76RL01830
Resource Type:
Conference
Resource Relation:
Conference: Conference on Lasers and Electro-Optics (CLEO 2017): Applications and Technology, May 14-19, 2017, San Jose, California, Paper No. AM1A.3
Country of Publication:
United States
Language:
English
Subject:
(140.3600) Lasers; tunable; (280.3420) Laser; sensors; (300.6340) Spectroscopy

Citation Formats

Phillips, Mark C., and Brumfield, Brian E. Standoff Detection of Isotopes in a NH3 Chemical Plume. United States: N. p., 2017. Web. doi:10.1364/CLEO_AT.2017.AM1A.3.
Phillips, Mark C., & Brumfield, Brian E. Standoff Detection of Isotopes in a NH3 Chemical Plume. United States. doi:10.1364/CLEO_AT.2017.AM1A.3.
Phillips, Mark C., and Brumfield, Brian E. Tue . "Standoff Detection of Isotopes in a NH3 Chemical Plume". United States. doi:10.1364/CLEO_AT.2017.AM1A.3.
@article{osti_1361011,
title = {Standoff Detection of Isotopes in a NH3 Chemical Plume},
author = {Phillips, Mark C. and Brumfield, Brian E.},
abstractNote = {We perform standoff detection of 14NH3 and 15NH3 at a 10 Hz rate in a chemical plume with varying concentration using an external cavity quantum cascade laser swept over the range 930-1065 cm-1.},
doi = {10.1364/CLEO_AT.2017.AM1A.3},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue May 30 00:00:00 EDT 2017},
month = {Tue May 30 00:00:00 EDT 2017}
}

Conference:
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  • Pacific Northwest National Laboratory (PNNL) has recently developed a hybrid infrared technique for standoff chemical detection. Active infrared detection typically involves a sender and receiver telescope separated by (100's) of meters and is quite sensitive, but is extremely cumbersome to align and is extremely sensitive to misalignment as the two telescopes must not only be parallel, but coaxial. Passive infrared sensing offers facile alignment (simply point the input optics), but relies on a happenstance temperature difference T between the chemical plume and its background. Often times the T found in the field is only 1 or 2 K, and themore » passive method is thus not very sensitive in many cases. The ''semi-active'' technique creates a large temperature difference T by placing an extended blackbody source at some distance away from the receiver telescope. The blackbody is designed to fill the telescope's FOV at a typical distance of 100 m, and provides a typical temperature difference T on the order of 80 to 100 K. Design considerations and experimental results in a direct comparison of passive, active, and semi-active measurements will be discussed« less
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  • No abstract prepared.
  • Pacific Northwest National Laboratory (PNNL) continues to expand its library of quantitative infrared reference spectra for remote sensing. The gas-phase data are recorded at 0.1 cm-1 resolution, with nitrogen pressure broadening to one atmosphere to emulate spectra recorded in the field. It is planned that the PNNL library will consist of approximately 500 vapor-phase spectra associated with DOE’s environmental, energy, and public safety missions. At present, the database is comprised of approximately 300 infrared spectra, many of which represent highly reactive or toxic species. For the 298 K data, each reported spectrum is in fact a composite spectrum generated bymore » a Beer’s law plot (at each wavelength) to typically 12 measured spectra. Recent additions to the database include the vapors of several semi-volatile and non-volatile liquids using an improved dissemination technique for vaporizing the liquid into the nitrogen carrier gas. Experimental and analytical methods are used to remove several known and new artifacts associated with FTIR gas-phase spectroscopy. Details concerning sample preparation and composite spectrum generation are discussed.« less
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