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981.
C. Spieles H. Stöcker C. Greiner 《The European Physical Journal C - Particles and Fields》1998,2(2):351-358
Measured hadron yields from relativistic nuclear collisions can be equally well understood in two physically distinct models,
namely a static thermal hadronic source vs. a time-dependent, nonequilibrium hadronization off a quark-gluon plasma droplet.
Due to the time-dependent particle evaporation off the hadronic surface in the latter approach the hadron ratios change (by
factors of ) in time. Final particle yields reflect time averages over the actual thermodynamic properties of the system at a certain
stage of the evolution. Calculated hadron, strangelet and (anti-)cluster yields as well as freeze-out times are presented
for different systems. Due to strangeness distillation the system moves rapidly out of the , plane into the -sector. Strangeness to baryon ratios prevail during a considerable fraction (50%) of the time evolution (i.e. -droplets or even -droplets form the system at the late stage: The possibility of observing this time evolution via two-particle correlations
is discussed). The observed hadron ratios require MeV and MeV. If the present model is fit to the extrapolated hadron yields, metastable hypermatter can only be produced with a probability
for .
Received: 15 April 1997 / Revised version: 5 June 1997 相似文献
982.
We present here an extension to any order of accuracy of the schemes proposed in Daru and Tenaud [J. Comput. Phys. 193 (2) (2004) 563–594] for the linear advection equation in 1D. Such schemes are then used for a high-order generalization of the Godunov method in the case of the wave equation and the locally linearized Euler equations. To cite this article: S. Del Pino, H. Jourdren, C. R. Acad. Sci. Paris, Ser. I 342 (2006). 相似文献
983.
Margaret W. Geiger Margaret M. Elliot Velissarios D. Karacostas Thomas J. Moricone Jesse B. Salmon Vincent L. Sideli Martha A. St . Onge 《Photochemistry and photobiology》1984,40(4):545-548
Abstract A series of ring-substituted phenyl and naphthyl azides have been prepared. Electronic absorption spectral properties and quantum yields of disappearance have been determined in aqueous solution. For phenyl azide derivatives, the wavelengths of maximum absorption vary systematically, correlating with electronic effects of the ring substituents. Quantum yield values of 0.1–0.7 are obtained and are independent of a number of experimental conditions, including concentration. There is no simple correlation of the quantum yields of azide disappearance with electronic effects, except that the naphthyl azides have higher photochemical efficiencies than the phenyl azide derivatives. A series of potential protein photolabels has been identified based on electronic absorption characteristics and photochemical efficiencies. 相似文献
984.
985.
Xonotlite alone or made more basic by doping of potassium -butoxide catalyses the title reaction between aromatic aldehydes and malononitrile or alkyl cyanoacetates. At ambient temperatures, this procedure specifically gives high yields of olefinic Knoevenagel products. 相似文献
986.
Thomas Stönner Darko Hanžel Brigitte Baretzky Klaus-Peter Lieb Peter Schaaf 《Hyperfine Interactions》1998,112(1-4):155-160
Fe-Al intermetallic alloys have been considered as protective materials against corrosion. We have studied the properties of such intermetallic coatings Fe x Al1?x (x ≤ 0.5) on the aluminum-rich side and their oxidation behaviour. The samples were prepared using rf-magnetron sputtering. The composition and layer thickness were determined by Rutherford Backscattering Spectrometry (RBS) and high-resolution scanning electron microscopy (HRSEM). Conversion Electron Mössbauer Spectroscopy (CEMS) and X-Ray Diffraction (XRD) were applied for phase analysis. We report here on the oxidation of such coatings. 相似文献
987.
C. Brandau F. Bosch B. Franzke L. Groening A. Hoffknecht H. Knopp C. Kozhuharov P.H. Mokler A. Müller Z. Stachura M. Steck T. Stöhlker T. Winkler 《Hyperfine Interactions》1998,114(1-4):263-266
After an extended upgrading period at the Experimental Storage Ring (ESR) of the GSI in Darmstadt, an experiment on recombination
of lithium-like uranium has been carried out. A 107.1 MeV/u U89+ beam with up to 500 μA effective current was stored and cooled. In addition to measurements of radiative recombination (RR)
and dielectronic recombination (DR) with high energy resolution in the range of 0–90 eV, the diagnostic properties of DR have
been utilized to characterize the new cooler setup. Preliminary experimental results for the 1s22p3/25ℓj(j=3/2,5/2) resonance manifolds are presented and compared with theoretical predictions.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
988.
Stöhlker T. Gumberidze A. Ma X. Beyer H. F. Bednarz G. Bosch F. Cai X. Fritzsche S. Hagmann S. Kozhuharov C. Klepper O. Liesen D. Mokler P. H. Sierpowski D. Stachura Z. Steck M. Surzhykov A. Toleikis S. Warczak A. Zou Y. 《Hyperfine Interactions》2003,148(1-4):97-102
Hyperfine Interactions - The magnetic order and crystallization of the amorphous Fe75Si15B10 alloy prepared by mechanical alloying was studied in situ by 57Fe Mössbauer spectroscopy. These... 相似文献
989.
H.W. Schäffer R.W. Dunford C. Kozhuharov A. Krämer T. Ludziejewski P.H. Mokler H.-T. Prinz P. Rymuza L. Sarkadi T. Stöhlker P. Swiat A. Warczak 《Hyperfine Interactions》1998,114(1-4):49-53
Progress on a measurement of the spectral distribution of the two-photon decay of the 21S0 level in helium-like gold is reported. A measurement of the exact shape of the continuous spectrum of the two-photon decay
in heavy helium-like ions provides a sensitive test on the details of the complete structure of a helium-like system. In our
experiment at GSI, a beam of 106.6 MeV/u Au77+ ions is excited by a thin Aluminum foil and the subsequent decays are observed in an array of Ge(i) detectors.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
990.