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This contribution introduces and illustrates the concept of fuzzy arithmetic as a modeling and analysis tool for the simulation of multibody systems subjected to uncertainties. The uncertainties are described by the use of fuzzy numbers and the simulation procedure is performed by employing the Transformation Method, which is a practical methodology for the implementation of fuzzy arithmetic. (© 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Oz E Deng S Katsouleas T Muggli P Barnes CD Blumenfeld I Decker FJ Emma P Hogan MJ Ischebeck R Iverson RH Kirby N Krejcik P O'Connell C Siemann RH Walz D Auerbach D Clayton CE Huang C Johnson DK Joshi C Lu W Marsh KA Mori WB Zhou M 《Physical review letters》2007,98(8):084801
The onset of trapping of electrons born inside a highly relativistic, 3D beam-driven plasma wake is investigated. Trapping occurs in the transition regions of a Li plasma confined by He gas. Li plasma electrons support the wake, and higher ionization potential He atoms are ionized as the beam is focused by Li ions and can be trapped. As the wake amplitude is increased, the onset of trapping is observed. Some electrons gain up to 7.6 GeV in a 30.5 cm plasma. The experimentally inferred trapping threshold is at a wake amplitude of 36 GV/m, in good agreement with an analytical model and PIC simulations. 相似文献
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Gabrielse G Bowden NS Oxley P Speck A Storry CH Tan JN Wessels M Grzonka D Oelert W Schepers G Sefzick T Walz J Pittner H Hänsch TW Hessels EA;ATRAP Collaboration 《Physical review letters》2002,89(23):233401
Cold antihydrogen is produced when antiprotons are repeatedly driven into collisions with cold positrons within a nested Penning trap. Efficient antihydrogen production takes place during many cycles of positron cooling of antiprotons. A first measurement of a distribution of antihydrogen states is made using a preionizing electric field between separated production and detection regions. Surviving antihydrogen is stripped in an ionization well that captures and stores the freed antiproton for background-free detection. 相似文献
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Gabrielse G Bowden NS Oxley P Speck A Storry CH Tan JN Wessels M Grzonka D Oelert W Schepers G Sefzick T Walz J Pittner H Hänsch TW Hessels EA 《Physical review letters》2002,89(21):213401
A background-free observation of cold antihydrogen atoms is made using field ionization followed by antiproton storage, a detection method that provides the first experimental information about antihydrogen atomic states. More antihydrogen atoms can be field ionized in an hour than all the antimatter atoms that have been previously reported, and the production rate per incident high energy antiproton is higher than ever observed. The high rate and the high Rydberg states suggest that the antihydrogen is formed via three-body recombination. 相似文献
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Gabrielse G Kolthammer WS McConnell R Richerme P Kalra R Novitski E Grzonka D Oelert W Sefzick T Zielinski M Fitzakerley D George MC Hessels EA Storry CH Weel M Müllers A Walz J;ATRAP Collaboration 《Physical review letters》2011,106(7):073002
Adiabatic cooling is shown to be a simple and effective method to cool many charged particles in a trap to very low temperatures. Up to 3×10(6) p are cooled to 3.5 K-10(3) times more cold p and a 3 times lower p temperature than previously reported. A second cooling method cools p plasmas via the synchrotron radiation of embedded e(-) (with many fewer e(-) than p in preparation for adiabatic cooling. No p are lost during either process-a significant advantage for rare particles. 相似文献
18.
Biological specimens have to be prepared for imaging in the electron microscope in a way that preserves their native structure. Two-dimensional (2D) protein crystals to be analyzed by electron crystallography are best preserved by sugar embedding. One of the sugars often used to embed 2D crystals is trehalose, a disaccharide used by many organisms for protection against stress conditions. Sugars such as trehalose can also be added to negative staining solutions used to prepare proteins and macromolecular complexes for structural studies by single-particle electron microscopy (EM). In this review, we describe trehalose and its characteristics that make it so well suited for preparation of EM specimens and we review specimen preparation methods with a focus on the use of trehalose. 相似文献
19.
Wolff M Steitz R Gutfreund P Voss N Gerth S Walz M Magerl A Zabel H 《Langmuir : the ACS journal of surfaces and colloids》2008,24(20):11331-11333
A 20% aqueous solution of (ethylene oxide) 99-(propylene oxide) 65-(ethylene oxide) 99, F127, was investigated by combining rheology in a cone/plate-geometry and surface-sensitive grazing incident neutron scattering. The crystalline structure formed by the polymer micelles becomes less pronounced for low shear rates, but correlations increase for higher shear rates. After stopping shear a slow relaxation of the micelles is found in the vicinity (50 mum thick layer) of a hydrophilic silicon wall (strong micelle-wall interaction), while a fast relaxation is observed in the boundary layer against the hydrophobic silicon wall (weak micelle-wall interaction). The results show that in the vicinity of the interface wall-particle interactions compete heavily with the shear force acting on the liquid. 相似文献