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排序方式: 共有247条查询结果,搜索用时 31 毫秒
231.
232.
Bai Z Bolton T Brown JS Bunnell KO Burchell M Burnett TH Cassell RE Coffman D Cook V Coward DH DeJongh F Dorfan DE Drinkard J Dubois GP Eigen G Eisenstein BI Freese T Gatto C Gladding G Grab C Heusch CA Hitlin DG Izen JM Kim PC Labs J Li A Lockman WS Mallik U Matthews CG Mincer AI Mir R Mockett PM Nemati B Odian A Parrish L Partridge R Pitman D Richman JD Sadrozinski HF Scarlatella M Schalk TL Schindler RH Seiden A Simopoulos C Stockdale IE Toki W Tripsas B Villa F Wang MZ Wasserbaech S 《Physical review letters》1991,67(8):1011-1014
233.
J.Z.Bai O.Bardon I.Blum A. Breakstone T.Burnett G.Chen G.P.Chen H.F.Chen J.Chen S.M.Chen Y.Q.Chen Y.Chen Y.B.Chen B.S.Cheng R.F.Cowan X.Z.Cui H.L.Ding Z.Z.DU W.Dunwoodie X.L.Fan J.Fang M.Fero C.S.Gao M.L.Gao S.Q.Gao P.Gratton J.H.Gu S.D.Gu W.X.Gu Y.F.Gu 《中国物理 C》1996,(12)
利用北京谱仪在北京正负电子对撞机上采集的350万(2S)事例,通过(2S)→γπ-和γK+K-反应道测量了Xc0的总宽度.由MonteCarlo模拟给出的质量分辨函数,利用拟合Xc2谱形得到的质量分辨作标定后,用于Xc0宽度的拟合,得到Xc0的宽度为(15.0)MeV.同时定出了XcJ(J=0,2)到π+π=和K+K-的衰变分支比.结果为B(Xc0→π+π-)=(4.27±0.23±O.60)×10-3;B(Xc0→K+K-)=(3.44±0.21±0.47×10-3;B(Xc2→π+π-)=(1.52±0.17±0.29)×10-3和B(Xc2→K+K-)=(5.2±1.1±1.8)×10-4,其中第一项误差为统计误差,第二项为系统误差。 相似文献
234.
G. M. Burnett G. G. Cameron P. L. Thorat 《Journal of polymer science. Part A, Polymer chemistry》1970,8(12):3455-3460
Crosslinking in the styrene–butadiene emulsion copolymerization (21 parts styrene:79 parts butadiene) prior to gelation has been studied by means of partial conversion number-average molecular weights at 5, 15, and 25°C. It is shown that the macromolecular population begins to diminish at progressively lower conversions as the reaction temperature is increased. This is attributed to the relative increase in crosslinking over propagation as the reaction temperature is increased and also to the decrease in mercaptan regulating index with increasing temperature. 相似文献
235.
We propose a method to probe states in the Mott insulator regime produced from a condensate in an optical lattice. We consider a system in which we create time-dependent number fluctuations in a given site by turning off the atomic interactions and lowering the potential barriers on a nearly pure Mott state to allow the atoms to tunnel between sites. We calculate the expected interference pattern and number fluctuations from such a system and show that one can potentially observe a deviation from a pure Mott state. We also discuss a method in which to detect these number fluctuations using time-of-flight imaging. 相似文献
236.
Abe K Abe K Abe T Adam I Akimoto H Aston D Baird KG Baltay C Band HR Barklow TL Bauer JM Bellodi G Berger R Blaylock G Bogart JR Bower GR Brau JE Breidenbach M Bugg WM Burke D Burnett TH Burrows PN Calcaterra A Cassell R Chou A Cohn HO Coller JA Convery MR Cook V Cowan RF Crawford G Damerell CJ Daoudi M de Groot N de Sangro R Dong DN Doser M Dubois R Erofeeva I Eschenburg V Etzion E Fahey S Falciai D Fernandez JP Flood K Frey R Hart EL Hasuko K Hertzbach SS Huffer ME Huynh X Iwasaki M 《Physical review letters》2001,86(7):1162-1166
We present final measurements of the Z boson-lepton coupling asymmetry parameters A(e), A(mu), and A(tau) with the complete sample of polarized Z bosons collected by the SLD detector at the SLAC Linear Collider. From the left-right production and decay polar angle asymmetries in leptonic Z decays we measure A(e) = 0.1544+/-0.0060, A(mu) = 0.142+/-0.015, and A(tau) = 0.136+/-0.015. Combined with our left-right asymmetry measured from hadronic decays, we find A(e) = 0.1516+/-0.0021. Assuming lepton universality, we obtain a combined effective weak mixing angle of sin (2)theta(eff)(W) = 0.230 98+/-0.000 26. 相似文献
237.
238.
R W Burnett A K Covington N Fogh-Andersen W R Külpman A H Maas O Müller-Plathe O Siggaard-Andersen A L Van Kessel P D Wimberley W G Zijlstra 《Journal of the International Federation of Clinical Chemistry》1994,6(4):115-120
Pre-analytical variables, e.g., specimen collection, transport, and storage, can contribute significantly to inaccurate pH, blood gas, and electrolyte values. The International Federation of Clinical Chemistry (IFCC), through its Committee on pH, Blood Gases and Electrolytes, has developed specific recommendations to minimize the undesirable effects of pre-analytical variables. The Committee has drawn upon the experiences of its own members as well as published data by others. Specifically, the Committee has included pertinent guidelines and suggestions by the IFCC Working Group on Selective Electrodes (WGSE), the National Committee on Clinical Laboratory Standards (NCCLS), and the Electrolyte/Blood Gas Division of the American Association for Clinical Chemistry (AACC). This paper will familiarize the reader with the effect of different types of specimen containers and anticoagulants. It discusses important aspects of specimen collection procedures including patient status and special precautions during specimen collection from indwelling catheters or cannulae. The paper also identifies different requirements in storage and transport of specimens for blood gas and electrolyte analysis. 相似文献
239.
K. Moriyasu T. Burnett D. Holmgren H.J. Lubatti D. Rees G. Swider B. Yuldashiev K. Dziunikowska A. Eskreys K. Eskreys A. Gula D. Kisielewska H. Rudnicka P. Stopa W. Ko R.L. Lander J.S. Pearson D. Pellett A. Zieminski 《Nuclear Physics B》1978,137(4):377-389
Double-scattering effects are studied in π?d interactions at 360 GeV/c. The partial cross sections are presented. The double-scattering probability per πd collision is found to be . We have extracted the partial cross section XN of the double-scattering plus interference contributions, and find that XN obeys KNO scaling. The data are compared with various theoretical predictions. 相似文献
240.
Upadhya PC Fan W Burnett A Cunningham J Davies AG Linfield EH Lloyd-Hughes J Castro-Camus E Johnston MB Beere H 《Optics letters》2007,32(16):2297-2299
The generation of terahertz (THz) transients in photoconductive emitters has been studied by varying the spatial extent and density of the optically excited photocarriers in asymmetrically excited, biased low-temperature-grown GaAs antenna structures. We find a pronounced dependence of the THz pulse intensity and broadband (>6.0 THz) spectral distribution on the pump excitation density and simulate this with a three-dimensional carrier dynamics model. We attribute the observed variation in THz emission to changes in the strength of the screening field. 相似文献