@article{SchaelReich2001,
  author    = {Schael, Frank and Reich, Oliver},
  title     = {In-situ-Analytik heterogener Medien mit frequenz- und leistungsmodulierten Diodenlasern},
  year      = {2001},
  abstract  = {Electronic intensity and frequency modulation of diode lasers enables new perspectives for highly sensitive analytical in-situ techniques. For analyis of "heterogeneous" media, which may consist of coexisting gaseous, liquid, and solid phases and often show multiple light scattering, non-invasive techniques with outstanding performance characteristics can be developed. Analysis of photon density waves launched by intensity-modulated lasers provide an elegant way for the determination of absorption and scattering coefficients of multiple scattering media. The absorption coefficient can be used for qualitative and quantitative analysis of chemical constituents (which absorb in the range of the laser wavelengths). The scattering coefficient allows characterization of physical and morphological properties of the sample. In the current work, applicability of appropriate radiation transport models was investigated with simple light scattering solutions and compared with results obtained from the treatment according to the theory of Kubelka and Munk. Measurements of human blood samples are discussed. A new method for determination of water vapor partial pressure in a polyurethane foam with a frequency-modulated external cavity diode laser is discussed.},
  language  = {de}
}
@article{SchaelEngelhardReich2001,
  author    = {Schael, Frank and Engelhard, Sonja and Reich, Oliver},
  title     = {Optische Sensorik f{\"u}r die in-situ-Analytik von Brauprozessen},
  year      = {2001},
  language  = {de}
}
@article{SchaelReichLoehmannsroeben2000,
  author    = {Schael, Frank and Reich, Oliver and L{\"o}hmannsr{\"o}ben, Hans-Gerd},
  title     = {Near infrared diode laser spectroscopy of organic compounds in turbid aqueous solutions},
  isbn      = {0-9528666-1-7},
  year      = {2000},
  abstract  = {Diffuse reflectance measurements and photon migration studies with near infrared (NIR) diode lasers were employed to elucidate experimental methods for determining absorption and scattering coefficients and species concentrations in highly scattering solutions. Applicability of theoretical approaches were established by investigating model systems with absorbing (e.g. ink, malachite green) and scattering (e.g. milk powder, caolinit) species in aqueous solution. While diffuse reflectance measurements practically requires calibration procedures, photon migration studies allow quantitative determination of absorption and scattering coefficients of turbid solutions consistent with absorptions coefficients obtained from Lambert-Beer's law. Furthermore, NIR absorption spectra of water, chlorinated hydrocarbons (chloroform, 1,2-dichloroethane, trichloroethene) and of various sugars (\$alpha\$-D-glucose, sucrose, maltose) are discussed. Spectral variations of NIR water absorption with temperature and solvents are exammined. Exemplary, NIR diode laser detection of water in acetone/water mixtures is performed.},
  language  = {en}
}
@article{LoehmannsroebenSchaelReichetal.2000,
  author    = {L{\"o}hmannsr{\"o}ben, Hans-Gerd and Schael, Frank and Reich, Oliver and Lemke, Matthias and Schober, Lars},
  title     = {Untersuchung von organischer Bodensubstanz und Bodengasen mit laser-spektroskopischer in-situ Meßtechnik},
  year      = {2000},
  language  = {de}
}