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Guido Belforte Federico Colombo Terenziano Raparelli Andrea Trivella Vladimir Viktorov 《Meccanica》2011,46(3):547-555
The demand of air bearings is increasing for those applications that require precision linear movements or high-speed rotations.
In particular in this paper air pads for air motion technology are studied. The paper analyses the effect of a circumferential
groove machined on the pad surface on pressure distribution, air flow consumption and stiffness. Two geometries are investigated
and compared: one with three supply orifices and the other with a circumferential groove as well. The static characteristics
of the pads are experimentally determined with also the pressure distributions under the pads along the radial and circumferential
directions. The experimental pressure distributions are compared with the simulated ones, obtained with a numerical program
at the purpose developed. The numerical model considers a general formulation of the supply holes discharge coefficient that
can be used also in presence of a circumferential groove. 相似文献
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William Porzio Guido Scavia Sergey Arnautov Lucia Conzatti Jérôme Charmet Edith Laux Herbert Keppner Giuseppe Zerbi Luigi Brambilla Alberto Bolognesi 《European Polymer Journal》2011,47(9):1725-1735
Poly(2-chloroxylylene) (PCX) thin films are obtained on the surface of liquids with different density and surface tension values. Morphology of these films is different showing increasing roughness and hydrophobicity in correlation with aforementioned physical parameters. A detailed study by means of vibrational spectroscopy, XRD and TEM of the structure of PCX at the interface with the liquid is reported. The results here obtained prove the possibility to tailor the surface of thin solid films of PCX changing the liquid substrate thus addressing the surface functionalities. 相似文献
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Valeria Marina Nurchi Guido Crisponi Isabel Villaescusa 《Coordination chemistry reviews》2010,254(17-18):2181-2192
After an overview of environmental pollution and the environmental threat posed by metals, this paper focuses on a literature survey of the different analytical methodologies and techniques used to investigate the functional groups involved in metal sorption onto biomass derived from agricultural waste. The recent literature has mainly focused on identifying the binding groups on the biomass surface through the use of different analytical techniques, from the traditional potentiometry to the most innovative and sophisticated solid surface analysis. In most of the biosorption studies, carboxylic group is the main origin for metal uptake, followed by hydroxyl group, aromatic ring and amine. The extent of the use of spectroscopic methods compared to traditional chemical analysis is being questioned. We stress that the study of biosorption mechanisms requires a multidisciplinary approach, and the efforts of analytical chemists and solution equilibrium experts really do contribute to the knowledge and to the optimization of these processes. This is the context in which we present a speciation study of the binding of various toxic metal ions by some coordinating groups on the biomass surface, which allows the classification of sorption mechanisms as a function of the pH dependence of the binding phenomena. 相似文献
1000.
Guido Sweers 《偏微分方程通讯》2013,38(8-9):1229-1247