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131.
Gumberidze A Stöhlker T Banaś D Beckert K Beller P Beyer HF Bosch F Cai X Hagmann S Kozhuharov C Liesen D Nolden F Ma X Mokler PH Orsić-Muthig A Steck M Sierpowski D Tashenov S Warczak A Zou Y 《Physical review letters》2004,92(20):203004
Radiative recombination transitions into the ground state of cooled bare and hydrogenlike uranium ions were measured at the storage ring ESR. By comparing the corresponding x-ray centroid energies, this technique allows for a direct measurement of the electron-electron contribution to the ionization potential in the heaviest He-like ions. For the two-electron contribution to the ionization potential of He-like uranium we obtain a value of 2248+/-9 eV. This represents the most accurate determination of two-electron effects in the domain of high-Z He-like ions, and the accuracy reaches already the size of the specific two-electron radiative QED corrections. 相似文献
132.
A. Świtaj-Zawadka P. Konieczka J. Szczygelska-Tao J. F. Biernat J. Wójcik A. Przyjazny J. Namieśnik 《Chromatographia》2004,60(7-8):433-439
The paper presents the results of research on a novel type of matrix-free reference materials for volatile organic compounds based upon thermal decomposition of appropriate immobilized compounds. The effect of parameters such as the kind of support (silica gel, porous glass, glass fiber) and the method of chemical modification of the support surface on the amount of chloromethane released as the analyte has been investigated. It was demonstrated that the amount of chloromethane released during thermal decomposition of immobilized compounds formed on the surface of silica gel and porous glass was larger when trimethylamine rather than N-morpholine was used for the preparation of immobilized compound. Reproducibility of the chemical modification procedure using silica gel and the stability of support with the immobilized compound were also examined. The full uncertainty budget of determination of liberated amount of chloromethane has been calculated. 相似文献
133.
Adamová D Agakichiev G Appelshäuser H Belaga V Braun-Munzinger P Castillo A Cherlin A Damjanović S Dietel T Dietrich L Drees A Esumi SI Filimonov K Fomenko K Fraenkel Z Garabatos C Glässel P Hering G Holeczek J Kushpil V Lenkeit B Ludolphs W Maas A Marín A Milosević J Milov A Miśkowiec D Panebrattsev Y Petchenova O Petrácek V Pfeiffer A Rak J Ravinovich I Rehak P Sako H Schmitz W Schukraft J Sedykh S Shimansky S Slívová J Specht HJ Stachel J Sumbera M Tilsner H Tserruya I Wessels JP Wienold T 《Physical review letters》2003,90(2):022301
Based on an evaluation of data on pion interferometry and on particle yields at midrapidity, we propose a universal condition for thermal freeze-out of pions in heavy-ion collisions. We show that freeze-out occurs when the mean free path of pions lambda(f) reaches a value of about 1 fm, which is much smaller than the spatial extent of the system at freeze-out. This critical mean free path is independent of the centrality of the collision and beam energy from the Alternating Gradient Synchrotron to the Relativistic Heavy Ion Collider. 相似文献
134.
135.
[reaction: see text] Vinylsilanes are formed in high yields in the reaction of representative acyl(trimethyl)silanes with anions generated from Kocienski's sulfones. 相似文献
136.
We observe that the saturation model of deep inelastic scattering predicts a geometric scaling of the total gamma(*)p cross section in the region of small Bjorken variable x. The geometric scaling in this case means that the cross section is a function of only one dimensionless variable tau = Q(2)R(2)(0)(x), where the function R(0)(x) decreases with decreasing x. We show that the experimental data from HERA in the region x<0.01 confirm the expectations of this scaling over a very broad region of Q(2). We suggest that the geometric scaling is more general than the saturation model. 相似文献
137.
We consider local field theory on κ-deformed Minkowski space which is an example of solvable Lie-algebraic noncommutative
structure. Using integration formula over κ-Minkowski space and κ-deformed Fourier transform, we consider for deformed local
fields the reality conditions as well as deformation of action functionals in standard Minkowski space. We present explicit
formulas for two equivalent star products describing CBH quantization of field theory on κ-Minkowski space. We express also
via star product technique the noncommutative translations in κ-Minkowski space by commutative translations in standard Minkowski
space.
Presented at the 9th Colloquium “Quantum Groups and Integrable Systems”, Prague, 22–24 June 2000.
Presented by J. Lukierski. 相似文献
138.
Joseph R. Lakowicz Henryk Cherek Józef Kuśba Ignacy Gryczynski Michael L. Johnson 《Journal of fluorescence》1993,3(2):103-116
This didactic paper summarizes the mathematical expressions needed for analysis of fluorescence anisotropy decays from polarized frequency-domain fluorescence data. The observed values are the phase angle difference between the polarized components of the emission and the modulated anisotropy, which is the ratio of the polarized and amplitude-modulated components of the emission. This procedure requires a separate measurement of the intensity decay of the total emission. The expressions are suitable for any number of exponential components in both the intensity decay and the anisotropy decay. The formalism is generalized for global analysis of anisotropy decays measured at different excitation wavelengths and for different intensity decay times as the result of quenching. Additionally, we describe the expressions required for associated anisotropy decays, that is, anisotropy decays where each correlation time is associated with a decay time present in the anisotropy decay. And finally, we present expressions appropriate for distributions of correlation times. This article should serve as a reference for researchers using frequency-domain fluorometry. 相似文献
139.
Oleg Palumbíny 《Czechoslovak Mathematical Journal》2003,53(2):467-477
The paper deals with oscillation criteria of fourth order linear differential equations with quasi-derivatives. 相似文献
140.
A method ("electrosorption") has been developed for separation of silver from copper by its deposition through internal electrolysis with hydrogen adsorbed on a platinum surface. The silver can then be stripped and determined by atomic-absorption spectrometry or the dithizone method. The activation of the platinum surface with adsorbed hydrogen can be achieved either electrolytically or by passing hydrogen gas through the solution in which the platinum is immersed. The method of electrosorption has been successfully applied to determination of trace levels of silver in copper metal. 相似文献