934
2004
eng
postprint
0
2006-11-01
--
--
NIR-diode laser spectroscopy for isotope-selective sensing of soil-respired carbon dioxide
The performance of a home-built tunable diode laser (TDL) spectrometer has been optimized regarding multi-line detection of carbon dioxide in natural gases. In the regime of the (30<SUP>0</SUP>1)<SUB>III</SUB> ← (000) band of <SUP>12</SUP>CO<SUB>2</SUB> around 1.6 μm, the dominating isotope species <SUP>12</SUP>CO<SUB>2</SUB>, <SUP>13</SUP>CO<SUB>2</SUB>, and <SUP>12</SUP>C<SUP>18</SUP>O<SUP>16</SUP>O were detected simultaneously. In contrast to most established techniques, selective measurements are performed without any sample preparation. This is possible since the CO<SUB>2</SUB> detection is free of interference from water, ubiquitous in natural gases. Detection limits in the range of a few ppmv were obtained for each species utilizing wavelength modulation (WM) spectroscopy with balanced detection in a long-path absorption cell set-up. Linear calibration plots cover a dynamic range of four orders of magnitude, allowing for quantitative CO<SUB>2</SUB> detection in various samples, like soil and breath gas. High isotopic resolution enables the excellent selectivity, sensitivity, and stability of the chosen analytical concept. The obtained isotopic resolution of typically ± 1.0 ‰ and ± 1.5 ‰ (for 3 vol. % and 0.7 vol. % of CO<SUB>2</SUB>, respectively) offers a promising analytical tool for isotope-ratio determination of carbon dioxide in soil gas. Preliminary experiments on soil respiration for the first time combine the on-line quantification of the overall carbon dioxide content with an optode sensor and isotopic determination (TDL system) of natural gas species.
urn:nbn:de:kobv:517-opus-10148
1014
Proc. SPIE Vol. 5544 (2004), pp. 47 - 54
<hr>
© 2004 <a href="http://www.spie.org/" target="_blanc">Society of Photo-Optical Instrumentation Engineers</a><br><br>
This paper was published in:<br>
<a href="http://bookstore.spie.org/index.cfm?fuseaction=DetailVolume&productid=542456&CFID=2785738&CFTOKEN=88552433" target="_blank">Remote Sensing and Modeling of Ecosystems for Sustainability </a> / Wei Gao, David R. Shaw (eds.), Proceedings of SPIE, Vol. 5544 (2004), pp. 47-54<br>
ISBN: 0-8194-5482-6<br>
<a href="http://dx.doi.org/10.1117/12.559551" target="_blank">DOI:10.1117/12.559551</a><br><br>
It is made available as an electronic reprint with permission of SPIE. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purpose, or modification of the content of the paper are prohibited.
VE 9908
mbeck@chem.uni-potsdam.de -5218
Gerald Hörner
Steffen Lau
Hans-Gerd Löhmannsröben
Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
paper 021
deu
swd
Kohlendioxid
deu
swd
Isotopenverhältnis
deu
uncontrolled
Bodengas
deu
uncontrolled
Diodenlaserspektroskopie
eng
uncontrolled
tunable diode laser (TDL)
eng
uncontrolled
carbon dioxide
eng
uncontrolled
isotope ratios
eng
uncontrolled
soil gas
Chemie und zugeordnete Wissenschaften
open_access
Institut für Chemie
Universität Potsdam
https://publishup.uni-potsdam.de/files/934/Hoerner2004.pdf
933
2006
eng
postprint
0
2006-11-01
--
--
Isotopic resolution of carbon monoxide and carbon dioxide by NIR diode laser spectroscopy
Near-infrared (NIR) absorption spectroscopy with tunable diode lasers allows the simultaneous detection of the three most important isotopologues of carbon dioxide (<SUP>12</SUP>CO<SUB>2</SUB>, <SUP>13</SUP>CO<SUB>2</SUB>, <SUP>12</SUP>C<SUP>18</SUP>O<SUP>16</SUP>O) and carbon monoxide (<SUP>12</SUP>CO, <SUP>13</SUP>CO, <SUP>12</SUP>C<SUP>18</SUP>O). The flexible and compact fiber-optic tunable diode laser absorption spectrometer (TDLAS) allows selective measurements of CO<SUB>2</SUB> and CO with high isotopic resolution without sample preparation since there is no interference with water vapour. For each species, linear calibration plots with a dynamic range of four orders of magnitude and detection limits (LOD) in the range of a few ppm were obtained utilizing wavelength modulation spectroscopy (WMS) with balanced detection in a Herriott-type multipass cell. The high performance of the apparatus is illustrated by fill-evacuation-refill cycles.
urn:nbn:de:kobv:517-opus-10135
1013
Proc. SPIE Vol. 6189 (2006), 618924, pp. 538-543
<hr>
© 2006 <a href="http://www.spie.org/" target="_blanc">Society of Photo-Optical Instrumentation Engineers</a><br><br>
This paper was published in:<br>
<a href="http://bookstore.spie.org/index.cfm?fuseaction=DetailVolume&productid=638624&CFID=2785738&CFTOKEN=88552433" target="_blank">Optical Sensing II</a> / Brian Culshaw, Anna G. Mignani, Hartmut Bartelt, Leszek R. Jaroszewicz (eds.), Proceedings of SPIE Vol. 6189 (2006), pp. 538-543 <br>
ISBN: 0-8194-6245-4<br>
<a href="http://dx.doi.org/10.1117/12.662765" target="_blank">DOI:10.1117/12.662765</a><br><br>
It is made available as an electronic reprint with permission of SPIE. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purpose, or modification of the content of the paper are prohibited.
VE 9908
mbeck@chem.uni-potsdam.de -5218
Steffen Lau
Katharina Salffner
Hans-Gerd Löhmannsröben
Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
paper 017
deu
swd
Isotop
deu
swd
Kohlenmonoxid
deu
swd
Kohlendioxid
deu
uncontrolled
Diodenlaserspektroskopie
eng
uncontrolled
isotope
eng
uncontrolled
carbon monoxide
eng
uncontrolled
carbon dioxide
eng
uncontrolled
diode laser spectroscopy
Chemie und zugeordnete Wissenschaften
open_access
Institut für Chemie
Universität Potsdam
https://publishup.uni-potsdam.de/files/933/Lau2006.pdf