On-line detection of oil on steel coils and thickness measurement using hyperspectral camera
The control of thickness homogeneity is a major concern in steel industry for quality issues. In the case of oil, an inhomogeneous coating on whole strip surface can create oxidation and lubrication trouble during coiling. Nowadays, different commercial solutions exist on the market (Light induced fluorescence, infrared gauges) but mainly for punctual measurements. The ability of new devices to characterize thin oil layers have been studied in this paper. This poster is focused on the study of spatial homogeneity for oil layer detection on steel surface for potential new online solution. The results presented in this paper confirm the interest of devices working in 3–5 μm spectral range to potentially answer to industrial needs.
Preliminary studies about thermal degradation of edible oils through attenuated total reflectance mid-infrared spectrometry
Abstract Degradation of edible oils during their heating process has been evaluated through the determination of cis -unsaturation and trans -fatty acids together with free fatty acids as a function of time and temperature heating. Two types of cooking oils, sunflower and seed (mixture of different seeds non-detailed), were heated at three different temperatures (147, 171 and 189 °C) during a total time of 1920 min (32 h) shared out in four sessions of 8 h each one, and samples were studied from their spectra obtained by Fourier transform infrared spectrometry using attenuated total reflectance measurements. A critical comparison between different multivariate calibration models built based on full spectra or selected wavenumbers, using both PLS1 and PLS2 algorithms, was carried out for a preliminary evaluation of the heating conditions (temperature and time) of oil samples.
Relation between the Infrared Spectra and the Lateral Specific Surface Areas of Gibbsite Samples
The chemical behavior of crystalline Al(OH)3 samples is governed by the lateral-to-basal surface ratio. For well-crystallized gibbsite samples possessing the two types of surfaces clearly spatially separated, a vibrational component at ∼3460 cm-1 in the infrared absorption spectra, not displayed in the Raman spectra, increases linearly with the lateral specific area determined by a gas adsorption isotherm. This intense and broad line is related to hydroxyl stretching modes of AlOH21/2+ or AlOH1/2- species present on the edge faces. However, it is too simplistic to assign this band to a mode of one or the other of these species. More complex structures combining both species should also be considered. When an evacuated sample is submitted during a short time to a D2O vapor injection, the OD spectral region displays essentially one broad component at 2563 cm-1, corresponding to the 3460 cm-1 band in the OH region and not to the other modes of the bulk hydroxyls. This experimental observation is also in agre...