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81.
E. Oltman P. Auchincloss R. E. Blair C. Haber S. R. Mishra M. Ruiz F. J. Sciulli M. H. Shaevitz W. H. Smith F. S. Merritt M. J. Oreglia P. G. Reutens R. Coleman H. E. Fis D. Levinthal W. Marsh P. A. Rapidis H. B. White D. Yovanovitch A. Bodek F. Borcherding N. Giokaris K. Lang I. E. Stockdale 《Zeitschrift fur Physik C Particles and Fields》1992,53(1):51-71
Structure functions obtained from high energy neutrino and antineutrino scattering from an iron target are presented. These were extracted from the combined data of Fermilab experiments E616 and E701; these utilized narrow band beam runs between 1979–1982. The structure functions are used to test the validity of quarkparton model (QPM) predictions and to extract the QCD scale parameter Λ from fits to the Altarelli-Parisi equations. 相似文献
82.
P. G. Reutens F. S. Merritt M. J. Oreglia P. Auchincloss R. E. Blair C. Haber S. R. Mishra E. Oltman M. Ruiz F. J. Sciulli M. H. Shaevitz W. H. Smith R. Zhu R. Coleman H. E. Fisk B. Jin T. Kondo D. Levinthal W. Marsh P. A. Rapidis H. B. White D. Yovanovitch A. Bodek F. Borcherding N. Giokaris K. Lang I. E. Stockdale 《Zeitschrift fur Physik C Particles and Fields》1990,45(4):539-550
We report a measurement of the electroweak parameters sin2θ w and ? based on the ratios of neutral current to charged current events measured in the Fermilab narrow-band neutrino beam at energies of 30–240 GeV. The data are fully corrected for radiative effects, heavy-quark production, and other effects. The best value for sin2θ w obtained, sin2θ w =0.239±0.011, is consistent with the most recent values fromW andZ production, as well as from other neutrino experiments. 相似文献
83.
Aaltonen T Abulencia A Adelman J Affolder T Akimoto T Albrow MG Amerio S Amidei D Anastassov A Anikeev K Annovi A Antos J Aoki M Apollinari G Arisawa T Artikov A Ashmanskas W Attal A Aurisano A Azfar F Azzi-Bacchetta P Azzurri P Bacchetta N Badgett W Barbaro-Galtieri A Barnes VE Barnett BA Baroiant S Bartsch V Bauer G Beauchemin PH Bedeschi F Behari S Bellettini G Bellinger J Belloni A Benjamin D Beretvas A Beringer J Berry T Bhatti A Binkley M Bisello D Bizjak I Blair RE Blocker C Blumenfeld B 《Physical review letters》2007,99(19):191806
We present a search for associated production of the chargino and neutralino supersymmetric particles using up to 1.1 fb{-1} of integrated luminosity collected by the CDF II experiment at the Tevatron pp collider at sq rt[s]=1.96 TeV. We analyze events with a large transverse momentum imbalance and either three charged leptons or two charged leptons of the same electric charge. The numbers of observed events are consistent with standard model expectations. Upper limits on the production cross section are derived in different theoretical models. 相似文献
84.
Abulencia A Adelman J Affolder T Akimoto T Albrow MG Ambrose D Amerio S Amidei D Anastassov A Anikeev K Annovi A Antos J Aoki M Apollinari G Arguin JF Arisawa T Artikov A Ashmanskas W Attal A Azfar F Azzi-Bacchetta P Azzurri P Bacchetta N Badgett W Barbaro-Galtieri A Barnes VE Barnett BA Baroiant S Bartsch V Bauer G Bedeschi F Behari S Belforte S Bellettini G Bellinger J Belloni A Benjamin D Beretvas A Beringer J Berry T Bhatti A Binkley M Bisello D Blair RE Blocker C Blumenfeld B Bocci A 《Physical review letters》2007,98(12):122001
We report a measurement of the Lambda b0 lifetime in the exclusive decay Lambda b0-->J/psi Lambda 0 in pp collisions at square root s=1.96 TeV using an integrated luminosity of 1.0 fb-1 of data collected by the CDF II detector at the Fermilab Tevatron. Using fully reconstructed decays, we measure tau(Lambda b0)=1.593(-0.078)(+0.083)(stat)+/-0.033(syst) ps. This is the single most precise measurement of tau(Lambda b0) and is 3.2sigma higher than the current world average. 相似文献
85.
Abulencia A Adelman J Affolder T Akimoto T Albrow MG Ambrose D Amerio S Amidei D Anastassov A Anikeev K Annovi A Antos J Aoki M Apollinari G Arguin JF Arisawa T Artikov A Ashmanskas W Attal A Azfar F Azzi-Bacchetta P Azzurri P Bacchetta N Badgett W Barbaro-Galtieri A Barnes VE Barnett BA Baroiant S Bartsch V Bauer G Bedeschi F Behari S Belforte S Bellettini G Bellinger J Belloni A Benjamin D Beretvas A Beringer J Berry T Bhatti A Binkley M Bisello D Blair RE Blocker C Blumenfeld B Bocci A 《Physical review letters》2007,98(11):112001
We present the first observation of exclusive e(+)e(-) production in hadron-hadron collisions, using pp[over] collision data at (square root) s = 1.96 TeV taken by the run II Collider Detector at Fermilab, and corresponding to an integrated luminosity of 532 pb(-1). We require the absence of any particle signatures in the detector except for an electron and a positron candidate, each with transverse energy E(T) > 5 GeV and pseudorapidity |eta| < 2. With these criteria, 16 events are observed compared to a background expectation of 1.9+/-0.3 events. These events are consistent in cross section and properties with the QED process pp[over] --> p + e(+)e(-) + p[over] through two-photon exchange. The measured cross section is 1.6(-0.3)(+0.5)(stat) +/- 0.3(syst) pb. This agrees with the theoretical prediction of 1.71+/-0.01 pb. 相似文献
86.
A critique on the structural analysis of lignins and application of novel tandem mass spectrometric strategies to determine lignin sequencing
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Joseph Banoub Guo‐Hua Delmas Jr. Nicolas Joly Grahame Mackenzie Nadja Cachet Bouchra Benjelloun‐Mlayah Michel Delmas 《Journal of mass spectrometry : JMS》2015,50(1):5-48
This review is devoted to the application of MS using soft ionization methods with a special emphasis on electrospray ionization, atmospheric pressure photoionization and matrix‐assisted laser desorption/ionization MS and tandem MS (MS/MS) for the elucidation of the chemical structure of native and modified lignins. We describe and critically evaluate how these soft ionization methods have contributed to the present‐day knowledge of the structure of lignins. Herein, we will introduce new nomenclature concerning the chemical state of lignins, namely, virgin released lignins (VRLs) and processed modified lignins (PML). VRLs are obtained by liberation of lignins through degradation of vegetable matter by either chemical hydrolysis and/or enzymatic hydrolysis. PMLs are produced by subjecting the VRL to a series of further chemical transformations and purifications that are likely to alter their original chemical structures. We are proposing that native lignin polymers, present in the lignocellulosic biomass, are not made of macromolecules linked to cellulose fibres as has been frequently reported. Instead, we propose that the lignins are composed of vast series of linear related oligomers, having different lengths that are covalently linked in a criss‐cross pattern to cellulose and hemicellulose fibres forming the network of vegetal matter. Consequently, structural elucidation of VRLs, which presumably have not been purified and processed by any other type of additional chemical treatment and purification, may reflect the structure of the native lignin. In this review, we present an introduction to a MS/MS top–down concept of lignin sequencing and how this technique may be used to address the challenge of characterizing the structure of VRLs. Finally, we offer the case that although lignins have been reported to have very high or high molecular weights, they might not exist on the basis that such polymers have never been identified by the mild ionizing techniques used in modern MS. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
87.
G. W. Scott Blair 《Rheologica Acta》1973,12(2):319-320
Summary
Reiner defined a numeric, which he called theDeborah Number to represent the ratio of a relaxation time to a natural (observation) time. This implies aMaxwell model but is readily extended to complete relaxation spectra. Similar Numbers are proposed for retardation times and also for some conditions of coagulation thixotropy and for data from certain psychophysical experiments. 相似文献
88.
Robert W. HumbleDanielle F. Middleton Joseph BanoubDavid F. Ewing Andrew N. Boa Grahame Mackenzie 《Tetrahedron letters》2011,52(47):6223-6227
Bredinin (4-carbamoyl-1-β-d-ribofuranosylimidazolium-5-olate, 1) was synthesised by the formation of a malonamate from 2,3-isopropylidene-d-ribofuranosylamine and ethyl malonyl chloride, followed by a sequence involving amination, via reduction of an oxime, heterocycle formation and then deprotection. 相似文献
89.
90.
We will prove that normal complex contact metric manifolds that are Bochner flat must have constant holomorphic sectional curvature 4 and be Kähler. If they are also complete and simply connected, they must be isometric to the odd-dimensional complex projective space \({{\mathbb{C}P^{2n+1}}}\)(4) with the Fubini-Study metric. On the other hand, it is not possible for normal complex contact metric manifolds to be conformally flat. 相似文献