@misc{SchultzeLemkeLoehmannsroeben2004,
  author    = {Schultze, Rainer H. and Lemke, Matthias and L{\"o}hmannsr{\"o}ben, Hans-Gerd},
  title     = {Laser-induced fluorescence (LIF) spectroscopy for the in situ analysis of petroleum product-contaminated soils},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-12271},
  year      = {2004},
  abstract  = {Contents: Introduction Experimental Techniques: The LIF demonstrator unit - The LIF demonstrator unit - The mobile LIF spectrometer OPTIMOS - Investigated petroleum products and soil samples Results and Discussion: Photophysical properties of the petroleum products LIF spectroscopic investigations of oil-spiked samples LIF spectroscopic investigations of real-world soils Conclusions},
  language  = {en}
}
@misc{LoehmannsroebenBeitzLuadienetal.2004,
  author    = {L{\"o}hmannsr{\"o}ben, Hans-Gerd and Beitz, Toralf and Luadien, Robert and Schultze, Rainer},
  title     = {Laser-based ion mobility spectrometry for sensing of aromatic compounds},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-11892},
  year      = {2004},
  abstract  = {The drift time spectra of polycyclic aromatic hydrocarbons (PAH), alkylbenzenes and alkylphenylethers were recorded with a laser-based ion mobility (IM) spectrometer. The ion mobilities of all compounds were determined in helium as drift gas. This allows the calculation of the diffusion cross sections (Omegacalc) on the basis of the exact hard sphere scattering model (EHSSM) and their comparison with the experimentally determined diffusion cross sections (Omegaexp). These Omegaexp/Omegacalc-correlations are presented for molecules with a rigid structure like PAH and prove the reliability of the theoretical model and experimental method. The increase of the selectivity of IM spectrometry is demonstrated using resonance enhanced multiphoton ionisation (REMPI) at atmospheric pressure, realized by tuneable lasers. The REMPI spectra of nine alkylbenzenes and alkylphenylethers are investigated. On the basis of these spectra, the complete qualitative distinction of eight compounds in a mixture is shown. These experiments are extended to alkylbenzene isomer mixtures.},
  language  = {en}
}
@misc{HoernerLauKantoretal.2004,
  author    = {H{\"o}rner, Gerald and Lau, Steffen and Kantor, Zoltan and L{\"o}hmannsr{\"o}ben, Hans-Gerd},
  title     = {Isotope selective analysis of CO2 with tunable diode laser (TDL) spectroscopy in the NIR},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-10167},
  year      = {2004},
  abstract  = {The performance of a home-built tunable diode laser (TDL) spectrometer, aimed at multi-line detection of carbon dioxide, has been evaluated and optimized. 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 without interference by water vapor. Detection limits in the range of few ppmv were obtained for each species utilizing wavelength modulation (WM) spectroscopy with balanced detection in a long-path absorption cell set-up. High sensitivity in conjunction with high precision —typically ±1 per mille and ±6 per mille for 3\% and 0.7\% of CO<SUB>2</SUB>, respectively— renders this experimental approach a promising analytical concept for isotope-ratio determination of carbon dioxide in soil and breath gas. For a moderate <SUP>12</SUP>CO<SUB>2</SUB> line, the pressure dependence of the line profile was characterized in detail, to account for pressure effects on sensitive measurements.},
  subject      = {Isotopenverh{\"a}ltnis},
  language  = {en}
}
@misc{HoernerLauLoehmannsroeben2004,
  author    = {H{\"o}rner, Gerald and Lau, Steffen and L{\"o}hmannsr{\"o}ben, Hans-Gerd},
  title     = {NIR-diode laser spectroscopy for isotope-selective sensing of soil-respired carbon dioxide},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-10148},
  year      = {2004},
  abstract  = {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  per mille and ± 1.5  per mille (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.},
  subject      = {Kohlendioxid},
  language  = {en}
}