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排序方式: 共有378条查询结果,搜索用时 15 毫秒
11.
Mathiazhagan C Molzon WR Cousins RD Konigsberg J Kubic J Melese P Rubin P Slater WE Wagner D Hart GW Kinnison WW Lee DM McKee RJ Milner EC Sanders GH Ziock HJ Arisaka K Knibbe P Urheim J Axelrod S Biery KA Irwin GM Lang K Margulies J Ouimette DA Ritchie JL Trang QH Wojcicki SG Auerbach LB Buchholz P Highland VL McFarlane WK Sivertz M Chapman MD Eckhause M Ginkel JF Hancock AD Joyce D Kane JR Kenney CJ Vulcan WF Welsh RE Whyley RJ Winter RG 《Physical review letters》1989,63(20):2181-2184
12.
13.
Adamson P Andreopoulos C Arms KE Armstrong R Auty DJ Ayres DS Baller B Barr G Barrett WL Becker BR Belias A Bernstein RH Bhattacharya D Bishai M Blake A Bock GJ Boehm J Boehnlein DJ Bogert D Bower C Buckley-Geer E Cavanaugh S Chapman JD Cherdack D Childress S Choudhary BC Coleman SJ Culling AJ de Jong JK Diwan MV Dorman M Dytman SA Escobar CO Evans JJ Falk Harris E Feldman GJ Frohne MV Gallagher HR Goodman MC Gouffon P Gran R Grashorn EW Grossman N Grzelak K Habig A Harris D Harris PG 《Physical review letters》2008,101(15):151601
A search for a sidereal modulation in the MINOS near detector neutrino data was performed. If present, this signature could be a consequence of Lorentz and CPT violation as predicted by the effective field theory called the standard-model extension. No evidence for a sidereal signal in the data set was found, implying that there is no significant change in neutrino propagation that depends on the direction of the neutrino beam in a sun-centered inertial frame. Upper limits on the magnitudes of the Lorentz and CPT violating terms in the standard-model extension lie between 10(-4) and 10(-2) of the maximum expected, assuming a suppression of these signatures by a factor of 10(-17). 相似文献
14.
Arisaka K Auerbach LB Axelrod S Belz J Biery KA Buchholz P Chapman MD Cousins RD Diwan MV Eckhause M Ginkel JF Guss C Hancock AD Heinson AP Highland VL Hoffmann GW Horvath J Irwin GM Joyce D Kaarsberg T Kane JR Kenney CJ Kettell SH Kinnison WW Knibbe P Konigsberg J Kuang Y Lang K Lee DM Margulies J Mathiazhagan C McFarlane WK McKee RJ Melese P Milner EC Molzon WR Ouimette DA Riley PJ Ritchie JL Rubin P Sanders GH Schwartz AJ Sivertz M Slater WE Urheim J Vulcan WF Wagner DL Welsh RE Whyley RJ 《Physical review letters》1993,71(24):3910-3913
15.
Adamson P Auty DJ Ayres DS Backhouse C Barr G Bishai M Blake A Bock GJ Boehnlein DJ Bogert D Cavanaugh S Cherdack D Childress S Coelho JA Coleman SJ Corwin L Cronin-Hennessy D Danko IZ de Jong JK Devenish NE Diwan MV Dorman M Escobar CO Evans JJ Falk E Feldman GJ Frohne MV Gallagher HR Gomes RA Goodman MC Gouffon P Graf N Gran R Grant N Grzelak K Habig A Harris D Hartnell J Hatcher R Himmel A Holin A Huang X Hylen J Ilic J Irwin GM Isvan Z Jaffe DE James C Jensen D Kafka T Kasahara SM Koizumi G 《Physical review letters》2011,107(1):011802
Results are reported from a search for active to sterile neutrino oscillations in the MINOS long-baseline experiment, based on the observation of neutral-current neutrino interactions, from an exposure to the NuMI neutrino beam of 7.07×10(20) protons on target. A total of 802 neutral-current event candidates is observed in the Far Detector, compared to an expected number of 754 ± 28(stat) ± 37(syst) for oscillations among three active flavors. The fraction f(s) of disappearing ν(μ) that may transition to ν(s) is found to be less than 22% at the 90% C.L. 相似文献
16.
Ambrose D Arroyo C Bachman M Connor D Eckhause M Graessle S Hancock AD Hartman K Hebert M Hoff CH Hoffmann GW Irwin GM Kane JR Kanematsu N Kuang Y Lang K Lee R Martin RD McDonough J Milder A Molzon WR Pommot-Maia M Riley PJ Ritchie JL Rubin PD Vassilakopoulos VI 《Physical review letters》2000,84(7):1389-1392
We report results from Experiment 871, performed at the BNL AGS, of a measurement of the branching ratio K(0)(L)-->&mgr;(+)&mgr;(-) with respect to the CP-violating mode K(0)(L)-->pi(+)pi(-). This experiment detected over 6200 candidate &mgr;(+)&mgr;(-) events, a factor of 6 more than that seen in all previous measurements combined. The resulting branching ratio gamma(K(0)(L)-->&mgr;(+)&mgr;(-))/gamma(K(0)(L)-->pi(+)pi(-)) = (3. 474+/-0.057)x10(-6) leads to a branching fraction B(K(0)(L)-->&mgr;(+)&mgr;(-)) = (7.18+/-0.17)x10(-9), which is consistent with the current world average, and reduces the uncertainty in this decay mode by a factor of 3. 相似文献
17.
Parts molded from reground BPA polycarbonate (PC) resin recovered from used objects do not always give the desired physical properties as parts molded from virgin resin. This loss of properties appears due to a surface hydrolysis of the PC which results in a reduction in molecular weight and formation of bis-phenol-A (BPA). The hydrolysis appears to be aided by exposure to uv-light and humidity. If the surface of the PC is washed with caustic solution, BPA and low MW oligomers are removed and many of the physical properties of the PC are restored. 相似文献
18.
Irwin M. Chaiken Yechiel Shai Giorgio Fassina Paolo Caliceti 《Macromolecular Symposia》1988,17(1):269-279
Analytical high performance liquid affinity chromatography (analytical HPLAC) has been investigated as an experimental guide to both synthetic design and affinity technological use of peptide and protein recognition surfaces. This work has progressed from the ongoing use of analytical affinity chromatography to study interaction mechanisms of naturally-occurring peptides and proteins, including enzyme fragment complexes and neuroendocrine biosynthetic precursors. We recently initiated a study to use analytical HPLAC for de novo design of recognition peptides called “anti-sense peptides”. Present data suggest the potential to use anti-sense peptides as “synthetic antibodies”, in immobilized forms, for biomolecular separation and analysis. Analogous studies have been started with immobilized natural antibodies in analytical immuno HPLAC. Our present data typify the growing usefulness of analytical HPLAC when designing recognition molecules, analyzing their interaction characteristics, and devising ways to use them in affinity technology. 相似文献
19.
In this paper we analyse a two-stage game involving the government and n agents who engage in a single activity (driving). The government establishes the legal policy setting and the agents proceed to play a non-cooperative game of incomplete information with a risk of accident in which their behavioral strategy is their level of care. We examine the Nash-equilibrium conditions for single-activity accidents between heterogeneous agents, ‘good’ drivers or ‘bad’ drivers allowing a variable damage function and a liability rule defined on the cube. The relative desirability for society of alternative equilibria and the conditions under which they can obtain are discussed. The constraints which circumscribe the ability of the government to induce an equilibrium involving careful driving are demonstrated. It transpires that when the proportion of good drivers increases, it becomes more difficult to sustain a careful equilibrium whereas an equilibrium of reckless behavior becomes easier to sustain. Various extensions of the models are also presented. 相似文献
20.
We consider the problem of approximating an optimal solution to a separable, doubly infinite mathematical program (P) with lower staircase structure by solutions to the programs (P(N)) obtained by truncating after the firstN variables andN constraints of (P). Viewing the surplus vector variable associated with theNth constraint as a state, and assuming that all feasible states are eventually reachable from any feasible state, we show that the efficient set of all solutions optimal to all possible feasible surplus states for (P(N)) converges to the set of optimal solutions to (P). A tie-breaking algorithm which selects a nearest-point efficient solution for (P(N)) is shown (for convex programs) to converge to an optimal solution to (P). A stopping rule is provided for discovering a value ofN sufficiently large to guarantee any prespecified level of accuracy. The theory is illustrated by an application to production planning.The work of Robert L. Smith was partially supported by the National Science Foundation under Grant ECS-8700836. 相似文献