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排序方式: 共有822条查询结果,搜索用时 0 毫秒
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W. Seidel P. Colling S. Cooper D. Dummer F. v. Feilitzsch P. Ferger G. Forster M. Frank H. -J. Gebauer J. Igalson E. Kellner U. Nagel A. Nucciotti F. Pröbst A. Rulofs L. Stodolsky 《Journal of Low Temperature Physics》1993,93(3-4):797-802
We plan a dark matter search using cryogenic calorimetric detectors with superconducting phase transition thermometers. We discuss such an experiment, compare its estimated sensitivity range with other dark matter searches, and discuss its planned realization. 相似文献
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Batteries: Carbon‐Based Anodes for Lithium Sulfur Full Cells with High Cycle Stability (Adv. Funct. Mater. 9/2014) 下载免费PDF全文
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Jan Brückner Sören Thieme Falko Böttger‐Hiller Ingolf Bauer Hannah Tamara Grossmann Patrick Strubel Holger Althues Stefan Spange Stefan Kaskel 《Advanced functional materials》2014,24(9):1284-1289
The lithium sulfur battery system has been studied since the late 1970s and has seen renewed interest in recent years. However, even after three decades of intensive research, prolonged cycling can only be achieved when a large excess of electrolyte and lithium is used. Here, for the first time, a balanced and stable lithium sulfur full cell is demonstrated with silicon–carbon as well as all‐carbon anodes. More than 1000 cycles, a specific capacity up to 1470 mAh g?1 sulfur (720 mAh g?1 cathode), and a high coulombic efficiency of over 99% even with a low amount of electrolyte are achieved. The alternative anodes do not suffer from electrolyte depletion, which is found to be the main cause of cell failure when using metallic lithium anodes. 相似文献
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DM Edgar WF Seidel KW Gee NC Lan G Field H Xia JE Hawkinson S Wieland RB Carter PL Wood 《Canadian Metallurgical Quarterly》1997,282(1):420-429
Signal detectability was measured in three temporal conditions as a function of the bandwidth and configuration of simultaneous maskers that either did or did not spectrally overlap the signal. The 20-ms signal was 250 Hz wide and was centered at 2500 Hz (fs). Although there were marked individual differences, performance was typically poorer when signal onset came 1 ms rather than 250 ms after the onset of a 420-ms masker, and poorest when signal onset came 1 ms after the onset of a 23-ms masker. The results support the idea that two separate across-channel processes contribute to temporal changes in signal detectability. One process contributes to the improvement observed as signal onset is delayed from masker onset, and its influence is reduced by the presence of masking components at fs only when the masker extends exclusively below fs. The other process is associated with the improvement observed as masker offset is delayed from signal offset, and its influence is reduced by the presence of masking components at fs when the masker extends exclusively above, or both below and above fs. Both of these processes are primarily activated by frequencies ranging from 0.6 to 0.8fs and 1.2 to 1.4fs. The data also demonstrate that the measured critical bandwidth narrows as signal onset is delayed from masker onset. 相似文献
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Refinement-oriented probability for CSP 总被引:1,自引:1,他引:0
Carroll Morgan Annabelle McIver Karen Seidel J. W. Sanders 《Formal Aspects of Computing》1996,8(6):617-647
Jones and Plotkin give a general construction for forming a probabilistic powerdomain over any directed-complete partial order [Jon90, JoP89]. We apply their technique to the failures/divergences semantic model for Communicating Sequential Processes [Hoa85].The resulting probabilistic model supports a new binary operator, probabilistic choice, and retains all operators of CSP including its two existing forms of choice. An advantage of using the general construction is that it is easy to see which CSP identities remain true in the probabilistic model. A surprising consequence however is that probabilistic choice distributes through all other operators; such algebraic mobility means that the syntactic position of the choice operator gives little information about when the choice actually must occur. That in turn leads to some interesting interaction between probability and nondeterminism.A simple communications protocol is used to illustrate the probabilistic algebra, and several suggestions are made for accommodating and controlling nondeterminism when probability is present.All authors are members of the Programming Research Group; McIver and Seidel are supported by the EPSRC.0 相似文献