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71.
Iwata N Tani K Watada A Ikeura-Sekiguchi H Araki T Hitchcock AP 《Micron (Oxford, England : 1993)》2006,37(4):290-295
Toners are micron scale polymer particles constructed of several kinds of resin, pigment, wax, etc. Transmission electron microscopy (TEM) is used for observation of the dispersion of the component materials in toners, but TEM images cannot identify simultaneously all components. Scanning transmission X-ray microscopy (STXM) not only provides simultaneous observation of spatial distributions of wax, resin and carbon black in toners, but it also provides detailed, quantitative, chemical information about the wax and resin environments through chemical component maps derived from multiple energy image sequences. The capabilities of STXM for toner analysis are illustrated by results of a study of a toner for black/white copy/print applications. 相似文献
72.
Chaimae Bariki Fabien Halter Fabien Thiesset Christian Chauveau Iskender Gökalp Ketana Teav Sina Kheirkhah Adam M. Steinberg 《Proceedings of the Combustion Institute》2019,37(2):1911-1918
Simultaneous measurements of temperature, CH* and OH* chemiluminescent species are carried out to explore the impact of stretch rate and curvature on the structure of premixed flames. The configuration of an initially flat premixed flame interacting with a toroidal vortex is selected for the present study and reasons for this choice are discussed. Lewis number effects are assessed by comparing methane and propane flames. It is emphasized that the flame structure experiences very strong variations. In particular, the flame is shrunk (broadened) in the initial (final) period of the interaction with the vortex where strain rate (curvature) contribution of the stretch rate is predominant. By further analysing independently the thickness of the preheat and reaction zones, it is shown that for propane flames, not only the former but also the latter is significantly altered in zones where the flame curvature is negative. Changes in the reaction zone properties are further emphasized using CH* and OH* radicals. It is demonstrated that higher thermal diffusivity plays a significant role around curved regions, in which the enhanced diffusion of heat leads to a strong increase of CH* compared to OH* intensity. As an overall conclusion, this study suggests that it would be interesting to reassess the internal flame structure at lower and moderate Karlovitz numbers since changes might appear for a moderate vortex intensity with typical size much larger than the flame thickness. 相似文献
73.
G. Dersch R. Beckmann G. Feige T. Lund P. Vater R. Brandt 《Isotopes in environmental and health studies》2013,49(6):303-304
A recent article interpreted the experiment by Dersch et al. on the formation of 24Na in 40Ar + Cu interactions in a very simple manner. The results from emulsion experiments performed with 3.6 AGeV 22Ne were adapted for the interpretation of the experiments with 1.8 AGeV 40Ar. The model used the same mean value for the energy of minimum ionizing protons and pions at all angles. It is argued that a more complex approach is needed for a satisfactory interpretation. 相似文献
74.
Adam NE Alexander JP Berkelman K Cassel DG Crede V Duboscq JE Ecklund KM Ehrlich R Fields L Galik RS Gibbons L Gittelman B Gray R Gray SW Hartill DL Heltsley BK Hertz D Jones CD Kandaswamy J Kreinick DL Kuznetsov VE Mahlke-Krüger H Meyer TO Onyisi PU Patterson JR Peterson D Phillips EA Pivarski J Riley D Ryd A Sadoff AJ Schwarthoff H Shi X Shepherd MR Stroiney S Sun WM Urner D Wilksen T Weaver KM Weinberger M Athar SB Avery P Breva-Newell L Patel R Potlia V Stoeck H Yelton J Rubin P Cawlfield C 《Physical review letters》2006,96(8):082004
We observe signals for the decays psi(3770) --> XJ/psi from data acquired with the CLEO detector operating at the CESR e+ e- collider with square root of s = 3773 MeV. We measure the following branching fractions Beta(psi(3770) --> XJ/psi and significances: (189 +/- 20 +/- 20) x 10(-5) (11.6sigma) for X = pi+ pi-, (80 +/- 25 +/- 16) x 10(-5) (3.4sigma) for X = pi0 pi0, and (87 +/- 33 +/- 22) x 10(-5) (3.5sigma) for X = eta, where the errors are statistical and systematic, respectively. The radiative return process e+ e- --> gamma psi(2S) populates the same event sample and is used to measure Gamma ee[psi(2S)] = (2.54 +/- 0.03 +/- 0.11) keV. 相似文献
75.
Rosner JL Adam NE Alexander JP Berkelman K Cassel DG Duboscq JE Ecklund KM Ehrlich R Fields L Gibbons L Gray R Gray SW Hartill DL Heltsley BK Hertz D Jones CD Kandaswamy J Kreinick DL Kuznetsov VE Mahlke-Krüger H Meyer TO Onyisi PU Patterson JR Peterson D Phillips EA Pivarski J Riley D Ryd A Sadoff AJ Schwarthoff H Shi X Stroiney S Sun WM Wilksen T Weinberger M Athar SB Avery P Breva-Newell L Patel R Potlia V Stoeck H Yelton J Rubin P Cawlfield C Eisenstein BI Karliner I Kim D Lowrey N Naik P 《Physical review letters》2006,96(12):121801
We present the first experimental limits on high-q2 contributions to charmless semileptonic decays of the form expected from the weak annihilation (WA) decay mechanism. Such contributions could bias determinations of /Vub/ from inclusive measurements of B-->Xulupsilon. Using a wide range of models based on available theoretical input we set a limit of GammaWA/Gammab-->u<7.4% (90% confidence level) on the WA fraction, and assess the impact on previous inclusive determinations of /Vub/. 相似文献
76.
Peter Adam Vladimir A. Andreev Margarita A. Man’ko Vladimir I. Man’ko 《Journal of Russian Laser Research》2017,38(6):491-506
We review the quantizer–dequantizer formalism of constructing symbols of the density operators and quantum observables, such as Wigner functions and tomographic-probability distributions. We present a tutorial consideration of the technique of obtaining minimal sets of dequantizers (quorum) related to the observable eigenvalues for one-qubit states. We discuss a generalization of the quantizer–dequantizer scheme on the example of spin-1/2 states. We consider the possibilities of extending the results to two-qubit systems using spin tomograms of the state density matrix. 相似文献
77.
P. Abreu W. Adam T. Adye E. Agasi R. Aleksan G. D. Alekseev A. Algeri S. Almehed S. J. Alvsvaag U. Amaldi et al. 《Zeitschrift fur Physik C Particles and Fields》1994,61(3):407-419
The study of the properties of inclusive production ofD
s
mesons and of events in which a and a muon are present in the same jet provides two independent measurements of the probability,f
s
w
, for a heavy quark to hadronize into a strangeB orD meson. The data sample analysed corresponds to 243,000 hadronicZ
0 decays. The combined value of these measurements isf
s
w
=0.19±0.06±0.08. From the flight distance distributions ofD
s and of (-lepton) secondary vertices, with the lepton emitted at high transverse momentum relative to the jet axis, two values are obtained for theB
s
0
meson lifetime. Combining these measurements with a previous result based on the study ofD
s- events, theB
s
0
meson lifetime is measured to be: 0.96±0.37 ps. 相似文献
78.
Chatrchyan S Khachatryan V Sirunyan AM Tumasyan A Adam W Bergauer T Dragicevic M Erö J Fabjan C Friedl M Frühwirth R Ghete VM Hammer J Hänsel S Hartl C Hoch M Hörmann N Hrubec J Jeitler M Kasieczka G Kiesenhofer W Krammer M Liko D Mikulec I Pernicka M Rohringer H Schöfbeck R Strauss J Teischinger F Wagner P Waltenberger W Walzel G Widl E Wulz CE Mossolov V Shumeiko N Suarez Gonzalez J Benucci L De Wolf EA Janssen X Maes T Mucibello L Ochesanu S Roland B Rougny R Selvaggi M Van Haevermaet H 《Physical review letters》2011,106(21):212301
A search for Z bosons in the μ(+)μ(-) decay channel has been performed in PbPb collisions at √S(NN)=2.76 TeV with the CMS detector at the LHC, in a 7.2 μb(-1) data sample. The number of opposite-sign muon pairs observed in the 60-120 GeV/c(2) invariant mass range is 39, corresponding to a yield per unit of rapidity (y) and per minimum bias event of [33.8±5.5(stat)±4.4(syst)]×10(-8), in the |y|<2.0 range. Rapidity, transverse momentum, and centrality dependencies are also measured. The results agree with next-to-leading order QCD calculations, scaled by the number of incoherent nucleon-nucleon collisions. 相似文献
79.
Khachatryan V Sirunyan AM Tumasyan A Adam W Bergauer T Dragicevic M Erö J Fabjan C Friedl M Frühwirth R Ghete VM Hammer J Hänsel S Hartl C Hoch M Hörmann N Hrubec J Jeitler M Kasieczka G Kiesenhofer W Krammer M Liko D Mikulec I Pernicka M Rohringer H Schöfbeck R Strauss J Taurok A Teischinger F Waltenberger W Walzel G Widl E Wulz CE Mossolov V Shumeiko N Suarez Gonzalez J Benucci L Ceard L Cerny K De Wolf EA Janssen X Maes T Mucibello L Ochesanu S Roland B Rougny R Selvaggi M Van Haevermaet H 《Physical review letters》2011,106(1):011801
The results of the first search for long-lived gluinos produced in 7 TeV pp collisions at the CERN Large Hadron Collider are presented. The search looks for evidence of long-lived particles that stop in the CMS detector and decay in the quiescent periods between beam crossings. In a dataset with a peak instantaneous luminosity of 1×10(32) cm-2 s-1, an integrated luminosity of 10 pb-1, and a search interval corresponding to 62 hours of LHC operation, no significant excess above background was observed. Limits at the 95% confidence level on gluino pair production over 13 orders of magnitude of gluino lifetime are set. For a mass difference mg - mχ1(0) >100 GeV/c2, and assuming BR(g→gχ1(0))=100%, mg < 370 GeV/c2 are excluded for lifetimes from 10 μs to 1000 s. 相似文献
80.
Chatrchyan S Khachatryan V Sirunyan AM Tumasyan A Adam W Bergauer T Dragicevic M Erö J Fabjan C Friedl M Frühwirth R Ghete VM Hammer J Hänsel S Hoch M Hörmann N Hrubec J Jeitler M Kiesenhofer W Krammer M Liko D Mikulec I Pernicka M Rohringer H Schöfbeck R Strauss J Taurok A Teischinger F Wagner P Waltenberger W Walzel G Widl E Wulz CE Mossolov V Shumeiko N Suarez Gonzalez J Bansal S Benucci L De Wolf EA Janssen X Maes J Maes T Mucibello L Ochesanu S Roland B Rougny R Selvaggi M Van Haevermaet H 《Physical review letters》2011,107(9):091802
Electroweak production of the top quark is measured for the first time in pp collisions at √=7 TeV, using a data set collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 36 pb?1. With an event selection optimized for t-channel production, two complementary analyses are performed. The first one exploits the special angular properties of the signal, together with background estimates from the data. The second approach uses a multivariate analysis technique to probe the compatibility with signal topology expected from electroweak top-quark production. The combined measurement of the cross section is 83.6±29.8(stat+syst)±3.3(lumi) pb, consistent with the standard model expectation. 相似文献