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991.
Y.M. Lau I. Roghair N.G. Deen M. van Sint Annaland J.A.M. Kuipers 《Chemical engineering science》2011,(14):48
The present paper describes an Euler–Lagrange model utilizing a drag closure derived from direct numerical simulations (front-tracking model) for (i) single isolated bubbles and (ii) bubbles rising in bubble swarms, expressed as a function of the local gas fraction. The model is applied to the prediction of an air/water system in a bubble column and for which experimental data is available. The effect of variation in size of the mapping window for the interphase coupling between the Eulerian and Lagrangian framework is investigated for both closure relations. It is found that the drag closure as a function of the local gas fraction is an improvement over the use of the drag closure for isolated single bubbles for the prediction of bubbly flow. 相似文献
992.
993.
Kanitz O. Windhausen Schwaibold Riffart W. Schreiber Jesser J. J. van Eck Diemair W. Ludorff J. Ph. Bruno Roßmann H. J. Steinbeck Wodsak H. Damm G. Steinhoff L. W. Jirak Fr. Bartschat H. Ketterl J. Großfeld W. Bartels G. Stamm Reichard R. Grau 《European Food Research and Technology》1937,73(5):448-504
994.
995.
European Food Research and Technology - 相似文献
996.
v. Schröder Karl Boresch K. Dirr R. Ammon Diemair Griebel Schwaibold G. Mall Felicitas Rolleri Kanitz O. Windhausen K. Felix von Querner W. Ludorff E. Fischbach W. Sutthoff Frey-Wyssling Schormüller A. Pirson J. Großfeld E. Chytrek Koelitz Hans Hawelka W. Schreiber Brüning Estler Pawletta W. Wodsak Jesser H. J. Steinbeck Seuss Schmitz Lars Erlandsen W. Hämmerle Masch A. Bäurle W. Leithe Rudolj Abderhalden Haevecker Fr. Bartschat Garber G. Stamm Gertraude Körner-Hennig G. Steinhoff Johannes Wolf Rob Jungkunz Schönfeld Ed. Rentz Klinc K. Höll 《European Food Research and Technology》1940,79(6):568-608
997.
Schwaibold Schormüller Beckel W. Sutthoff Lars Erlandsen v. Skramlik W. Schreiber Kanitz Bierotte M. Steiner W. Wodsak G. Steinhoff H. J. Steinbeck Frey-Wyssling M. Gordienko K. Dirr Pawletta Stelzer W. Wodsak W. Bartels Hoepke G. Stamm Brüning W. Hämmerle Schnetka K. Felix H. Schülke Kluge Krzywanek W. Brandt Gertraude Körner-Hennig K. J. Demeter Damm J. Ph. Bruno Roßmann W. Karlowa H. Ketterl L. W. Jirak W. Preiß Diemair W. Ludorff Jahr Griebel J. J. van Eck W. Preiß C. Pyriki K. Müller Jesser K. Boresch Fr. Bartschat 《European Food Research and Technology》1939,77(3):290-336
998.
Two-stroke outboard engines have long been considered noisy and polluting devices. However, attitudes towards these engines are changing thanks to the introduction of new engine designs and high dilution, low pollution outboard oils. In this paper the development of such oils is described. It is shown that using esters, with their excellent lubricity and inherent biodegradability, it is possible to formulate outboard oils with high performance in all respects. When these oils are combined with automated oil supply systems, to avoid misblending and oil spillage, an optimal and environmentally friendly system is obtained. It is, however, desirable that appropriate legislation is established to speed up the introduction of these systems. 相似文献
999.
Luiz A. Canalle Sander S. van Berkel Laurens T. de Haan Jan C. M. van Hest 《Advanced functional materials》2009,19(21):3464-3470
The copper‐catalyzed azide–alkyne 1,3‐dipolar cycloaddition (CuAAC) is extensively used for the functionalization of well‐defined polymeric materials. However, the necessity for copper, which is inherently toxic, limits the potential applications of these materials in the area of biology and biomedicine. Therefore, the first entirely copper‐free procedure for the synthesis of clickable coatings for the immobilization of functional molecules is reported. In the first step, azide‐functional coatings are prepared by thermal crosslinking of side‐chain azide‐functional polymers and dialkyne linkers. In a second step, three copper‐free click reactions (i.e., the Staudinger ligation, the dibenzocyclooctyne‐based strain‐promoted azide–alkyne [3+2] cycloaddition, and the methyl‐oxanorbornadiene‐based tandem cycloaddition?retro‐Diels?Alder (crDA) reaction) are used to functionalize the azide‐containing surfaces with fluorescent probes, allowing qualitative comparison with the traditional CuAAC. 相似文献
1000.
van 't Erve O. Awo-Affouda C. Hanbicki A.T. Li C.H. Thompson P.E. Jonker B.T. 《Electron Devices, IEEE Transactions on》2009,56(10):2343-2347
We demonstrate that information can be transmitted and processed with pure spin currents in silicon. Fe/Al2O3 tunnel barrier contacts are used to produce significant electron spin polarization in the silicon, generating a spin current which flows outside of the charge current path. The spin orientation of this pure spin current is controlled in one of three ways: 1) by switching the magnetization of the Fe contact; 2) by changing the polarity of the bias on the Fe/Al2O3 "injector" contact, which enables the generation of either majority or minority spin populations in the Si, providing a way to electrically manipulate the injected spin orientation without changing the magnetization of the contact itself; and 3) by inducing spin precession through the application of a small perpendicular magnetic field. Spin polarization by electrical extraction is as effective as that achieved by the more common electrical spin injection. The output characteristics of a planar silicon three-terminal device are very similar to those of nonvolatile giant magnetoresistance metal spin-valve structures. 相似文献