@article{HassReich2011,
  author    = {Hass, Roland and Reich, Oliver},
  title     = {Photon density wave spectroscopy for dilution-free sizing of highly concentrated nanoparticles during starved-feed polymerization},
  series = {ChemPhysChem : a European journal of chemical physics and physical chemistry},
  volume    = {12},
  journal   = {ChemPhysChem : a European journal of chemical physics and physical chemistry},
  number    = {14},
  publisher = {Wiley-Blackwell},
  address   = {Malden},
  issn      = {1439-4235},
  doi       = {10.1002/cphc.201100323},
  pages     = {2572 -- 2575},
  year      = {2011},
  language  = {en}
}
@misc{HassSandmannReich2017,
  author    = {Hass, Roland and Sandmann, Michael and Reich, Oliver},
  title     = {Photonic sensing in highly concentrated biotechnical processes by photon density wave spectroscopy},
  series = {Proceedings SPIE 10323, 25th International Conference on Optical Fiber Sensors},
  volume    = {10323},
  journal   = {Proceedings SPIE 10323, 25th International Conference on Optical Fiber Sensors},
  publisher = {IEEE},
  address   = {New York},
  isbn      = {978-1-5090-4850-2},
  issn      = {0277-786X},
  doi       = {10.1117/12.2263617},
  pages     = {4},
  year      = {2017},
  abstract  = {Photon Density Wave (PDW) spectroscopy is introduced as a new approach for photonic sensing in highly concentrated biotechnical processes. It independently quantifies the absorption and reduced scattering coefficient calibration-free and as a function of time, thus describing the optical properties in the vis/NIR range of the biomaterial during their processing. As examples of industrial relevance, enzymatic milk coagulation, beer mashing, and algae cultivation in photo bioreactors are discussed.},
  language  = {en}
}
@misc{WernerMuenzbergHassetal.2016,
  author    = {Werner, Peter and M{\"u}nzberg, Marvin and Hass, Roland and Reich, Oliver},
  title     = {Process analytical approaches for the coil-to-globule transition of poly(N-isopropylacrylamide) in a concentrated aqueous suspension},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {944},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-43116},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-431162},
  pages     = {807 -- 819},
  year      = {2016},
  abstract  = {The coil-to-globule transition of poly(N-isopropylacrylamide) (PNIPAM) microgel particles suspended in water has been investigated in situ as a function of heating and cooling rate with four optical process analytical technologies (PAT), sensitive to structural changes of the polymer. Photon Density Wave (PDW) spectroscopy, Focused Beam Reflectance Measurements (FBRM), turbidity measurements, and Particle Vision Microscope (PVM) measurements are found to be powerful tools for the monitoring of the temperature-dependent transition of such thermo-responsive polymers. These in-line technologies allow for monitoring of either the reduced scattering coefficient and the absorption coefficient, the chord length distribution, the reflected intensities, or the relative backscatter index via in-process imaging, respectively. Varying heating and cooling rates result in rate-dependent lower critical solution temperatures (LCST), with different impact of cooling and heating. Particularly, the data obtained by PDW spectroscopy can be used to estimate the thermodynamic transition temperature of PNIPAM for infinitesimal heating or cooling rates. In addition, an inverse hysteresis and a reversible building of micrometer-sized agglomerates are observed for the PNIPAM transition process.},
  language  = {en}
}
@article{BresselReich2014,
  author    = {Bressel, Lena and Reich, Oliver},
  title     = {Theoretical and experimental study of the diffuse transmission of light through highly concentrated absorbing and scattering materials Part I: Monte-Carlo simulations},
  series = {Journal of quantitative spectroscopy \& radiative transfer},
  volume    = {146},
  journal   = {Journal of quantitative spectroscopy \& radiative transfer},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0022-4073},
  doi       = {10.1016/j.jqsrt.2014.01.007},
  pages     = {190 -- 198},
  year      = {2014},
  abstract  = {In many technical materials and commercial products like sunscreen or paint high particle and absorber concentrations are present. An important parameter for slabs of these materials is the diffuse transmission of light, which quantifies the total amount of directly and diffusely transmitted light. Due to the high content of scattering particles not only multiple scattering but also additional dependent scattering occurs. Hence, simple analytical models cannot be applied to calculate the diffuse transmission. In this work a Monte-Carlo program for the calculation of the diffuse transmission of light through dispersions in slab-like geometry containing high concentrations of scattering particles and absorbers is presented and discussed in detail. Mie theory is applied for the calculation of the scattering properties of the samples. Additionally, dependent scattering is considered in two different models, the well-known hard sphere model in the Percus-Yevick approximation (HSPYA) and the Yukawa model in the Mean Spherical Approximation (YMSA). Comparative experiments will show the accurateness of the program as well as its applicability to real samples [1]. (C) 2014 Elsevier Ltd. All rights reserved.},
  language  = {en}
}
@incollection{AscheBoeckmannLaueetal.2000,
  author    = {Asche, Hartmut and B{\"o}ckmann, Christine and Laue, Steffen and L{\"o}hmannsr{\"o}ben, Hans-Gerd and Lemke, Matthias and Schober, Lars and Reich, Oliver and L{\"u}ck, Erika and Sch{\"u}tte, Marc and Domsch, Horst and Makower, Alexander and Scheller, Frieder W. and St{\"o}cklein, Wolfgang and Wollenberger, Ursula and Schultze, Rainer and Hengstermann, Theo and Schael, Frank},
  title     = {Umweltforschung f{\"u}r das Land Brandenburg : Projekt Umweltanalytik / Umweltmeßtechnik / Informationssysteme},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-3862},
  publisher      = {Universit{\"a}t Potsdam},
  pages     = {176 -- 227},
  year      = {2000},
  language  = {de}
}
@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}
}
@article{AdebayoHashimHassetal.2017,
  author    = {Adebayo, Segun Emmanuel and Hashim, Norhashila and Hass, Roland and Reich, Oliver and Regen, Christian and M{\"u}nzberg, Marvin and Abdan, Khalina and Hanafi, Marsyita and Zude-Sasse, Manuela},
  title     = {Using absorption and reduced scattering coefficients for non-destructive analyses of fruit flesh firmness and soluble solids content in pear},
  series = {Postharvest Biology and Technology},
  volume    = {130},
  journal   = {Postharvest Biology and Technology},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0925-5214},
  doi       = {10.1016/j.postharvbio.2017.04.004},
  pages     = {56 -- 63},
  year      = {2017},
  abstract  = {Quality attributes of fruit determine its acceptability by the retailer and consumer. The objective of this work was to investigate the potential of absorption (μa) and reduced scattering (μs') coefficients of European pear to analyze its fruit flesh firmness and soluble solids content (SSC). The absolute reference values, μa* (cm-1) and μs'* (cm-1), of pear were invasively measured, employing multi-spectral photon density wave (PDW) spectroscopy at preselected wavelengths of 515, 690, and 940 nm considering two batches of unripe and overripe fruit. On eight measuring dates during fruit development, μa and μs' were analyzed non-destructively by means of laser light backscattering imaging (LLBI) at similar wavelengths of 532, 660, and 830 nm by means of fitting according to Farrell's diffusion theory, using fix reference values of either μa* or μs'*. Both, the μa* and the μa as well as μs'* and μs' showed similar trends. Considering the non-destructively measured data during fruit development, μa at 660 nm decreased 91 till 141 days after full bloom (dafb) from 1.49 cm-1 to 0.74 cm-1 due to chlorophyll degradation. At 830 nm, μa only slightly decreased from 0.41 cm-1 to 0.35 cm-1. The μs' at all wavelengths revealed a decreasing trend as the fruit developed. The difference measured at 532 nm was most pronounced decreasing from 24 cm-1 to 10 cm-1, while at 660 nm and 830 nm values decreased from 15 cm-1 to 13 cm-1 and from 10 cm-1 to 8 cm-1, respectively. When building calibration models with partial least-squares regression analysis on the optical properties for non-destructive analysis of the fruit SSC, μa at 532 nm and 830 nm resulted in a correlation coefficient of R = 0.66, however, showing high measuring uncertainty. The combination of all three wavelengths gave an enhanced, encouraging R = 0.89 for firmness analysis using μs' in the freshly picked fruit.},
  language  = {en}
}