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51.
The transverse mass spectra of Omega, J/psi, and psi' in Pb+Pb collisions at 158A GeV are studied within a hydrodynamical model of the quark-gluon-plasma expansion and hadronization. The model reproduces the existing data with the common hadronization parameters: temperature T = T(H) congruent with 170 MeV and average collective transverse velocity v(T) congruent with 0.2. 相似文献
52.
53.
J. Rutkowski P. Madejczyk A. Piotrowski W. Gawron K. Jóźwikowski A. Rogalski 《Opto-Electronics Review》2008,16(3):321-327
The performance of dual waveband HgCdTe photodiodes fabricated using metaloorganic chemical vapour deposition operated at
high temperatures is presented. The effect of additional separating layer on the quantum efficiency and cross-talk of the
photodiodes is analyzed. The photodiodes with cutoff wavelengths up to 6 μm, good R0A product, and high quantum efficiency at 200 K have been demonstrated. The temperature dependence of the differential resistance
is discussed. It is shown that the multilayer heterojunction P-n-N-n-P structure operating in a simultaneous mode has better
performance than a structure operating in a sequential mode. 相似文献
54.
Kaźmierkiewicz R Czaplewski C Lammek B Ciarkowski J 《Journal of computer-aided molecular design》1999,13(1):21-33
Subject of this work is the analysis of molecular dynamics (MD) trajectories of neurophysins I (NPI) and II (NPII) and their complexes with the neurophyseal nonapeptide hormones oxytocin (OT) and vasopresssin (VP), respectively, simulated in water. NPs serve in the neurosecretory granules as carrier proteins for the hormones before their release to the blood. The starting data consisted of two pairs of different trajectories for each of the (NPII/VP)2 and (NPI/OT)2 heterotetramers and two more trajectories for the NPII2 and NPI2 homodimers (six trajectories in total). Using essential dynamics which, to our judgement, is equivalent to factor analysis, we found that only about 10 degrees of freedom per trajectory are necessary and sufficient to describe in full the motions relevant for the function of the protein. This is consistent with these motions to explain about 90% of the total variance of the system. These principal degrees of freedom represent slow anharmonic motional modes, clearly pointing at distinguished mobility of the atoms involved in the protein's functionality. 相似文献
55.
Marek Gaździcki Mark I. Gorenstein Stanislaw Mrówczyński 《The European Physical Journal C - Particles and Fields》1998,5(1):129-133
The pion multiplicity per participating nucleon in central nucleus–nucleus collisions at the energies 2–15 AGeV is significantly smaller than in nucleon–nucleon interactions at the same collision energy. This effect of pion suppression is argued to appear due to the evolution of the system produced at the early stage of heavy–ion collisions towards a local
thermodynamic equilibrium and further isentropic expansion.
Received: 21 July 1997 / Revised version: 12 November 1997 / Published online: 26 February 1998 相似文献
56.
57.
Experimental dependence of two-photon absorption efficiency on statistical properties of laser light
The fluorescence intensity excited by two-photon absorption of the 514.5 nm argon laser line has been investigated for various oxasol derivatives. The fluorescence intensity was dependent on the statistical properties of the 514.5 nm argon laser line and was a factor 1.52-1.86 larger for absorption of a multifrequency laser line than in the case of a single frequency laser line. 相似文献
58.
The lowest variational upper bounds to the lowest 2S state of ?7.478044 au and to the lowest 2P state of ?7.410097 au of the lithium atom are obtained. 相似文献
59.
Alt C Anticic T Baatar B Barna D Bartke J Betev L Białkowska H Billmeier A Blume C Boimska B Botje M Bracinik J Bramm R Brun R Buncić P Cerny V Christakoglou P Chvala O Cramer JG Csató P Darmenov N Dimitrov A Dinkelaker P Eckardt V Farantatos G Flierl D Fodor Z Foka P Freund P Friese V Gál J Gaździcki M Georgopoulos G Gładysz E Grebieszkow K Hegyi S Höhne C Kadija K Karev A Kliemant M Kniege S Kolesnikov VI Kollegger T Kornas E Korus R Kowalski M Kraus I Kreps M van Leeuwen M Lévai P Litov L 《Physical review letters》2005,94(19):192301
Results are presented on Omega production in central Pb+Pb collisions at 40 and 158A GeV beam energy. For the first time in heavy ion reactions, rapidity distributions and total yields were measured for the sum Omega(-) + Omega(+) at 40A GeV and for Omega(-) and Omega(+) separately at 158A GeV. The yields are strongly underpredicted by the string-hadronic UrQMD model but agree better with predictions from hadron gas models. 相似文献
60.
The amorphous to crystalline transformation due to electron beam or heat treatments was studied. From the results it was concluded that the temperature of the transformation is higher than 300°C - higher than the epitaxy temperature for the deposition process. The a→c transition proceeds in several stages. By using the “cross-cut” method the activation energy for crystallization was estimated to be 2 eV. 相似文献