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Rotor‐stator‐machinery is characterized in continuous operation by a homogeneous power input and a defined residence time. The influence of the equipment configuration and process design in the laminar flow regime was considered little till now. In order to fill this knowledge gap, the process behavior of this type of device was systematically investigated experimentally under axial flow conditions, as well as an energetic optimization of the machine configuration was performed. 相似文献
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Steven Le Moan Tejas Madan Tanksale Roman Byshko Philipp Urban 《Journal of the Society for Information Display》2017,25(9):554-560
The effect of observer metamerism induced by electronic displays depends to a large extent on their primary spectra (red, green, and blue in the most common case). In particular, for narrow‐band primary spectra whose peak wavelength lies in the range of high variability of the observer's color‐matching function, some observers can experience very large differences between actual surface colors (e.g. in a light booth) and displayed colors if the monitor is optimized for the International Commission on Illumination (CIE) 1931 standard observer. However, because narrow‐band light‐emitting diodes lead to larger color gamuts, more and more monitors with very narrow band primaries are coming onto the market without manufacturers taking into account the associated problem of observer variations. Being able to measure these variations accurately and efficiently is therefore an important objective. In this paper, we propose a new approach to predict the extent of observer metamerism for a particular multiprimary display. Unlike existing dedicated models, ours does not depend on a reference illuminant and a set of reflectance spectra and is computationally more efficient. 相似文献
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Alf Mews Chaoyang Jiang Thomas Schuessler Guenther Philipp Y. Fan Marko Burghard 《Israel journal of chemistry》2001,41(1):15-22
The oxidation process of single-walled carbon nanotubes via nitric acid treatment was followed by IR-, UV-Vis-NIR, and single bundle Raman spectroscopy. The introduction of functional, oxygen-containing groups is revealed by an additional absorption band at 1725 cm−1, characteristic of carbonyl stretch vibrations. No significant shift of the optical absorption bands could be detected after oxidation. The combination of atomic force microscopy and confocal scanning resonance-enhanced Raman microscopy was used to investigate thin bundles and, eventually, individual nanotubes in detail. These experiments enabled determination of the dependence of the Raman intensity of the G-line (around 1590 cm−1) on the bundle height for both non-oxidized and oxidized tubes. The Raman cross-section of the oxidized tubes was found to be reduced by a factor of ˜4, compared to the pristine tubes. This observation is ascribed to all tubes within a bundle that are oxidized to the same degree. 相似文献
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In-situ full-field measurements became one of the drivers for process understanding, model creation, validation and inverse analysis. Therefore, a novel spatio-temporal optical flow method for the robust measurement of higher-order strain derivatives is proposed. This computer vision approach overcomes inherent restrictions of established DIC methods. For advanced process analysis of shear cutting processes, the deformation curvature (2nd-order displacement derivative) and the respective rate (3rd-order displacement derivative) are of high interest. For the first time, it is possible to quantify experimentally these higher-order derivatives in sufficient quality with the proposed spatio-temporal optical flow approach. In addition, interesting correlations between the microstructure of the material and macroscopic process results are determined. This demonstrates the potential of the novel in-situ measurement approach for the advanced process analysis of metal forming processes in general. 相似文献
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Biruk W. Hailesilassie Philipp Schuetz Iwan Jerjen Martin Hugener Manfred N. Partl 《Journal of Materials Science》2015,50(1):79-92
Foam bitumen is highly efficient in wetting and coating the surface of mineral aggregate at lower temperature. In order to improve understanding and characterization of the bitumen foam, X-ray radiography was used to study the formation and decay of bitumen foam in 2D representation. Image segmentation analysis was used to determine the foam bubble size distribution. In addition, the main parameters influencing foam bitumen formation, water content, and temperature were also investigated. The results demonstrate the influence of the water content on morphology and expansion of foam bitumen bubbles. Adding more water in the foaming process leads to quick collapse of bubbles and intensifies coalescence of foam bitumen. Higher temperatures produces larger bubbles at early foaming stage compared to lower temperature. Moreover the morphology of bubble formation depends on the types of bitumen used. An exponential function has been implemented to represent the bubble area distribution. 相似文献
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