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31.
The thermopower of NbHx alloys for x varying from 0.607 to 0.883 has been examined at temperatures ranging from 100 to 430 K. It was found that the transition from orthorhombic β to cubic α' phase is accompanied by a strong change of thermopower. It is concluded that differences in phonon spectra of these two phases are responsible for the observed differences in the transport properties. The sensitivity of the thermopower to any other phase transitions in this system has been observed as well. 相似文献
32.
Zeitschrift für Physik C Particles and Fields - Parent-parent on-shell semi-local duality relations betweens − andu-channel resonances in πN amplitudes are studied. The duality... 相似文献
33.
M. Sawicka I. Matea H. Grawe R. Grzywacz M. Pfützner M. Lewitowicz J. M. Daugas B. A. Brown A. Lisetskiy F. Becker G. Bélier C. Bingham R. Borcea E. Bouchez A. Buta E. Dragulescu G. de France G. Georgiev J. Giovinazzo F. Hammache F. Ibrahim P. Mayet V. Méot F. Negoita F. De Oliveira-Santos O. Perru O. Roig K. Rykaczewski M. G. Saint-Laurent J. E. Sauvestre O. Sorlin M. Stanoiu I. Stefan C. Stodel Ch. Theisen D. Verney J. Żylicz 《The European Physical Journal A - Hadrons and Nuclei》2004,22(3):455-459
A decay spectroscopy study of the neutron-rich cobalt isotopes has been performed using fragmentation of a 86Kr36+ beam and the new LISE2000 spectrometer at GANIL. For 71Co and 73Co, the -delayed radiation has been observed for the first time, and the half-lives were found to be 79(5) ms and 41(4) ms, respectively. Features of the decay are discussed qualitatively in terms of nuclear models. 相似文献
34.
35.
O. Kavatsyuk C. Mazzocchi Z. Janas A. Banu L. Batist F. Becker A. Blazhev W. Brüchle J. Döring T. Faestermann M. Górska H. Grawe A. Jungclaus M. Karny M. Kavatsyuk O. Klepper R. Kirchner M. La Commara K. Miernik I. Mukha C. Plettner A. Płochocki E. Roeckl M. Romoli K. Rykaczewski M. Schädel K. Schmidt R. Schwengner J. Żylicz 《The European Physical Journal A - Hadrons and Nuclei》2007,31(3):319-325
The β decay of the very neutron-deficient isotope 101Sn was studied at the GSI on-line mass separator using silicon detectors for recording charged particles and germanium detectors
for γ-ray spectroscopy. Based on the β-delayed proton data the production cross-section of 101Sn in the 50Cr + 58Ni fusion-evaporation reaction was determined to be about 60nb. The half-life of 101Sn was measured to be 1.9(3)s. For the first time β-delayed γ-rays of 101Sn were tentatively identified, yielding weak evidence for a cascade of 352 and 1065keV transitions in 101In. The results for the 101Sn decay as well as those from previous work on the 103Sn decay are discussed by comparing them to predictions obtained from shell model calculations employing a new interaction
in the 88Sr to 132Sn model space. 相似文献
36.
We study the complete lattice of convergences, that is, of relations between a set and the set of its filters. Various properties of convergences (like isotonicity, antitonicity, being a pseudotopology, a pretopology, an adherence) determine subsets of the lattice of convergences which possess certain particular features called “cyrtological”. The morphisms associated to these sets, said “cyrtomorphisms”, are basic in the study of convergences. A method of generation of GALOIS connections relative to cyrtomorphisms is proposed. Semigroups generated by some cyrtomorphisms are analyzed. 相似文献
37.
Nils A. Törnqvist Piotr Żenczykowski 《Zeitschrift fur Physik C Particles and Fields》1986,30(1):83-97
In current QCD inspired analyses of the hadron spectrum nonperturbative quark loops are generally neglected. We study the validity of this assumption by estimating mass splittings and mixings induced by hadronic mass renormalization to the (70,1?) baryon multiplet. All intermediate states in the loop composed of a ground state meson (0?+, 1??) and a ground state baryon (1/2+, 3/2+) are included. We use a3 P 0 type model for the partial decay widths and spectral functions. Using unitarity and analyticity one finds a definite prediction for the masses and mixings, in good agreement with experiment, even when the perturbative one-gluon exchange is completely ignored. Our result thus allows for a smaller one-gluon exchange overall contribution, which would resolve the difficulty of the apparent smallness of the observed spin-orbit coupling. In particular if one adds the (nonperturbative) unitarity corrections to the one-gluon exchange contribution the gluon coupling constant can be reduced by a factor of 3 giving a reasonable value αs≈0.3. 相似文献
38.
Jacek Achrem‐Achremowicz Elżbieta Kępczyńska Marek Żylewski Zbigniew Janeczko 《Biomedical chromatography : BMC》2010,24(3):261-267
A series of superlipophilic or highly lipophilic semisynthetic betulin derivatives was prepared and their relative lipophilicity was measured by reversed‐phase thin‐layer chromatography (RP‐TLC) at different pH values using 1,4‐dioxane–acetate buffer mixtures as mobile phases. Cholesterol, 17β‐estradiol and pure betulin were used as the reference compounds. Linear relationships were found between RM values and 1,4‐dioxane concentrations in the mobile phases. LogP values were also calculated with computer programs ACD/LogP (ChemSketch 11.0, Advanced Chemistry Development Inc.) and ClogP (Daylight Chemical Information Systems Inc.). The empirical and theoretical data were compared, and the RM0 values correlated well with logP. Two of the synthesized betulin derivatives are reported for the first time. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
39.
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
40.