@article{SchmidtZiemannPentzienetal.2016,
  author    = {Schmidt, Birgit Angelika and Ziemann, Martin Andreas and Pentzien, Simone and Gabsch, Toralf and Koch, Werner and Kr{\"u}ger, J{\"o}rg},
  title     = {Technical analysis of a Central Asian wall painting detached from a Buddhist cave temple on the northern Silk Road},
  series = {Studies in Conservation},
  volume    = {61},
  journal   = {Studies in Conservation},
  publisher = {Routledge, Taylor \& Francis Group},
  address   = {Abingdon},
  issn      = {0039-3630},
  doi       = {10.1179/2047058414Y.0000000152},
  pages     = {113 -- 122},
  year      = {2016},
  abstract  = {A great number of Central Asian wall paintings, archeological materials, architectural fragments, and textiles, as well as painting fragments on silk and paper, make up the so called Turfan Collection at the Asian Art Museum in Berlin. The largest part of the collection comes from the Kucha region, a very important cultural center in the third to ninth centuries. Between 1902 and 1914, four German expeditions traveled along the northern Silk Road. During these expeditions, wall paintings were detached from their original settings in Buddhist cave complexes. This paper reports a technical study of a wall painting, existing in eight fragments, from the Buddhist cave no. 40 (Ritterhohle). Its original painted surface is soot blackened and largely illegible. Gruwedel, leader of the first and third expeditions, described the almost complete destruction of the rediscovered temple complex and evidence of fire damage. The aim of this case study is to identify the materials used for the wall paintings. Furthermore, soot deposits as well as materials from conservation interventions were of interest. Non-invasive analyses were preferred but a limited number of samples were taken to provide more precise information on the painting technique. By employing optical and scanning electron microscopy, energy dispersive X-ray spectroscopy, micro X-ray fluorescence spectroscopy, X-ray diffraction analysis, and Raman spectroscopy, a layer sequence of earthen render, a ground layer made of gypsum, and a paint layer containing a variety of inorganic pigments were identified.},
  language  = {en}
}
@article{ZudePflanzSpinellietal.2011,
  author    = {Zude, Manuela and Pflanz, Michael and Spinelli, Lorenzo and Dosche, Carsten and Torricelli, Alessandro},
  title     = {Non-destructive analysis of anthocyanins in cherries by means of Lambert-Beer and multivariate regression based on spectroscopy and scatter correction using time-resolved analysis},
  series = {Journal of food engineering},
  volume    = {103},
  journal   = {Journal of food engineering},
  number    = {1},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0260-8774},
  doi       = {10.1016/j.jfoodeng.2010.09.021},
  pages     = {68 -- 75},
  year      = {2011},
  abstract  = {In high-value sweet cherry (Prunus avium), the red coloration - determined by the anthocyanins content - is correlated with the fruit ripeness stage and market value. Non-destructive spectroscopy has been introduced in practice and may be utilized as a tool to assess the fruit pigments in the supply chain processes. From the fruit spectrum in the visible (Vis) wavelength range, the pigment contents are analyzed separately at their specific absorbance wavelengths. A drawback of the method is the need for re-calibration due to varying optical properties of the fruit tissue. In order to correct for the scattering differences, most often the spectral intensity in the visible spectrum is normalized by wavelengths in the near infrared (NIR) range, or pre-processing methods are applied in multivariate calibrations. In the present study, the influence of the fruit scattering properties on the Vis/NIR fruit spectrum were corrected by the effective pathlength in the fruit tissue obtained from time-resolved readings of the distribution of time-of-flight (DTOF). Pigment analysis was carried out according to Lambert-Beer law, considering fruit spectral intensities, effective pathlength, and refractive index. Results were compared to commonly applied linear color and multivariate partial least squares (PLS) regression analysis. The approaches were validated on fruits at different ripeness stages, providing variation in the scattering coefficient and refractive index exceeding the calibration sample set. In the validation, the measuring uncertainty of non-destructively analyzing fruits with Vis/NIR spectra by means of PLS or Lambert-Beer in comparison with combined application of Vis/NIR spectroscopy and DTOF measurements showed a dramatic bias reduction as well as enhanced coefficients of determination when using both, the spectral intensities and apparent information on the scattering influence by means of DTOF readings. Corrections for the refractive index did not render improved results.},
  language  = {en}
}