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31.
R. Suntz H. Becker P. Monkhouse J. Wolfrum 《Applied physics. B, Lasers and optics》1988,47(4):287-293
Two-dimensional laser-induced fluorescence (2D-LIF) imaging of OH radicals, excited at 308 nm, has been employed to visualize the flame front in an internal combustion engine burning air/propane mixtures. Light sheet thicknesses down to 70 m have been attained for excitation. Hydroxyl radicals were detected up to pressures of 7.5 bar at engine speeds of 500 rpm. An upper limit of 300 m for the flame front thickness was obtained from line intensity profiles. 相似文献
32.
Baltrusaitis RM Becker JJ Blaylock GT Brown JS Bunnell KO Burnett TH Cassell RE Coffman D Cook V Coward DH Cui H Del Papa C Dorfan DE Duncan AL Einsweiler KF Eisenstein BI Fabrizio R Gladding G Grancagnolo F Hamilton RP Hauser J Heusch CA Hitlin DG Köpke L Mockett PM Moss L Mozley RF Nappi A Odian A Partridge R Perrier J Plaetzer SA Richman JD Roehrig JR Russell JJ Sadrozinski HF Scarlatella M Schalk TL Schindler RH Seiden A Sleeman JC Spadafora AL Thaler JJ Toki W Unno Y Villa F Wattenberg A 《Physical review letters》1985,55(17):1723-1726
33.
S. Barlag H. Becker T. Böhringer M. Bosman V. Castillo V. Chabaud D. Buchholz C. Damerell C. Daum H. Dietl H. Fawcett S. Gill A. Gillman R. Gilmore T. Gooch L. Görlich P. Gras Z. Hajduk E. Higon B. D. Hyams D. P. Kelsey J. Kemmer R. Klanner U. Kötz S. Kwan B. Lücking G. Lütiens G. Lutz J. Malos W. Männer E. Neugebauer H. Palka M. Pepé J. Richardson G. De Rijk K. Rybicki H. J. Seebrunner U. Stierlin H. G. Tiecke M. Turala G. Waltermann S. Watts P. Weilhammer F. Wickens L. W. Wiggers A. Wylie T. Zeludziewicz ACCMOR Collaboration 《Zeitschrift fur Physik C Particles and Fields》1987,37(1):17-23
We have measured the lifetimes of hadronically produced charged and neutralD mesons using silicon microstrip detectors and an active silicon target in the NA32 spectrometer at the CERN SPS. We obtainτ D± = (10.9± 1.5 1.9 )·10?13s andτ D (?)10 = (4.2±0.5)·10?13s based on 59 and 90 fully reconstructed decays respectively, giving a ratioτ D±/τ D (?)10 of 2.6 ±0.5. 相似文献
34.
P. Willsau H. Hübel W. Korten F. Azaiez M. A. Deleplanque R. M. Diamond A. O. Macchiavelli F. S. Stephens H. Kluge F. Hannachi J. C. Bacelar J. A. Becker M. J. Brinkman E. A. Henry A. Kuhnert T. F. Wang J. A. Draper E. Rubel 《Zeitschrift für Physik A Hadrons and Nuclei》1992,344(3):351-352
Lifetimes of superdeformed states in194Pb were measured by the Doppler-shift attenuation method. Quadrupole moments around 20 eb, that are constant over the observed frequency range, are derived. The results rule out large centrifugal stretching effects. 相似文献
35.
We report the formation of homogeneous and stable V2O3 nanocrystals, directly from V2O5 thin films, at 600 °C, as observed by using in situ electron microscopy experiments. Thermally-induced reduction of V2O5 thin films in vacuum is remarkably different when compared to reduction of V2O5 single crystals and results in the formation of nanophase V2O3. Thermally grown V2O3 nanocrystals exhibit hexagon or square shape and are stable at higher temperature as well as room temperature. The formation of stable nanocrystals through the reduction process in a non-chemical environment (vacuum) could provide a basis for understanding the complex processes of vanadium oxide phase transitions and for controlling the chemical processes to produce oxide nanocrystals. 相似文献
36.
37.
H. Fawcett S. Barlag H. Becker E. Belau T. Böhringer M. Bosman V. Castillo V. Chabaud D. Bucholz C. Damerell C. Daum G. De Rijk H. Dietl S. Gill A. Gillman R. Gilmore T. Gooch P. Gras Z. Hajduk E. Higon B. Hyams D. Kelsey J. Kemmer R. Klanner U. Kötz S. Kwan B. Lücking G. Lütjens G. Lutz J. Malos W. Männer E. Neugebauer H. Palka M. Pepé G. Polok J. Richardson M. Rozanska K. Rybicki H. Seebrunner U. Stierlin R. Tapper H. Tiecke M. Turala G. Waltermann S. Watts P. Weilhammer F. Wickens L. Wiggers A. Wylie T. Zeludziewicz ACCMOR Collaboration 《Zeitschrift fur Physik C Particles and Fields》1990,46(4):513-519
The production of the neutralK ? (892) resonances by 200 GeVK ? andπ ? has been studied over the kinematic range 0.0<x f<1.0 andp t 2 <5.0 GeV2. Longitudinal and transverse momentum distributions are presented. In addition the decay angular distributions inK ? fragmentation to \(\bar K^{0*} \) have been investigated. 相似文献
38.
Bruno Becker Paolo Giulio Franciosa Stephan Gschwind Stefano Leonardi Thomas Ohler Peter Widmayer 《Journal of Algorithms in Cognition, Informatics and Logic》1996,21(3):520-541
In this paper, we face the problem of computing an enclosing pair of axis-parallel rectangles of a set of polygonal objects in the plane, serving as a simple container. We propose anO(nα(n)log n) worst-case time algorithm, where α( ) is the inverse Ackermann's function, for finding, given a setMof points, segments and polygons defined bynvertices, a pair of axis-parallel rectangles (s, t) such thats∪tencloses all objects inMand area(s)+area(t) is minimum. The algorithm works inO(nα(n) log log n) worst-case space. Moreover, we prove an Ω(n log n) lower bound for the one-dimensional version of the problem. We also show that for the special case of enclosing a set of polygons with axis-parallel sides, our algorithm runs in optimal worst-case timeO(n log n), using worst-case spaceO(n log log n). 相似文献
39.
A. Hoffknecht O. Uwira A. Frank S. Schennach W. Spies M. Wagner S. Schippers A. Müller R. Becker M. Kleinod N. Angert P.H. Mokler 《Hyperfine Interactions》1998,114(1-4):257-261
The origin of the widely observed enhancement of rates for electron-ion recombination at very low energies is still unknown.
We investigated the recombination of Au25+ with free electrons in a merged-beams experiment at the UNILAC accelerator of the GSI in Darmstadt. At E
rel= 0 eV we found an enormous enhancement factor of 365 compared to the theory of radiative recombination. An increase of the
electron density by a factor of 10 had not much influence on the measured rate coefficient.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
40.
M. Houry R. Lucas M.-G. Porquet Ch. Theisen M. Girod M. Aiche M.M. Aleonard A. Astier G. Barreau F. Becker J.F. Chemin I. Deloncle T.P. Doan J.L. Durell K. Hauschild W. Korten Y. Le Coz M.J. Leddy S. Perries N. Redon A.A. Roach J.N. Scheurer A.G. Smith B.J. Varley 《The European Physical Journal A - Hadrons and Nuclei》1999,6(1):43-48