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81.
82.
Minimal colorings for properly colored subgraphs 总被引:1,自引:0,他引:1
We give conditions on the minimum numberk of colors, sufficient for the existence of given types of properly edge-colored subgraphs in ak-edge-colored complete graph. The types of subgraphs we study include families of internally pairwise vertex-disjoint paths with common endpoints, hamiltonian paths and hamiltonian cycles, cycles with a given lower bound of their length, spanning trees, stars, and cliques. Throughout the paper, related conjectures are proposed.Research supported by a European Union PECO grant under identification number CIPA3510PL929589, while on leave at University Paris-XI 相似文献
83.
A theoretically predicted phenomenon, the spatially inhomogeneous saturation of the gain caused by amplified spontaneous emission, was investigated. The direct measurements of the population of excited states are in good qualitative agreement with the theoretical calculations. 相似文献
84.
85.
A chelate-forming cellulose, iminodiacetic acid/ethylcellulose (IDAEC), is applied to the collection of metals from ammonium citrate and acetate solutions. A method is devised for the i.c.p./a.e.s. determination of metal contaminants in magnesium by separation and preconcentration of the metals with IDAEC. 相似文献
86.
87.
We study two classes of modules for order preserving symplectic and order preserving even special orthogonal rook monoids. The first class of modules are indexed by admissible sets, and the second are the regular representations. For the first class we show that every submodule is cyclic and completely reducible, and for each irreducible component when restricted to a module over a proper submonoid we explore its module properties. For the second we provide explicitly their decompositions into irreducible submodules using admissible sets. 相似文献
88.
Perru O Sorlin O Franchoo S Azaiez F Bouchez E Bourgeois C Chatillon A Daugas JM Dlouhy Z Dombrádi Z Donzaud C Gaudefroy L Grawe H Grévy S Guillemaud-Mueller D Hammache F Ibrahim F Le Coz Y Lukyanov SM Matea I Mrazek J Nowacki F Penionzhkevich YE de Oliveira Santos F Pougheon F Saint-Laurent MG Sletten G Stanoiu M Stodel C Theisen Ch Verney D 《Physical review letters》2006,96(23):232501
The reduced transition probabilities B(E2;0(+) --> 2(+)(1)) of the neutron-rich (74)Zn and (70)Ni nuclei have been measured by Coulomb excitation in a (208)Pb target at intermediate energy. These nuclei have been produced at Grand Accélérateur National d'Ions Lourds via interactions of a 60A MeV (76)Ge beam with a Be target. The B(E2) value for (70)Ni(42) is unexpectedly large, which indicates that neutrons added above N=40 strongly polarize the Z=28 proton core. In the Zn isotopic chain, the steep rise of B(E2) values beyond N=40 continues up to (74)Zn(44). The enhanced proton core polarization in (70)Ni is attributed to the monopole interaction between the neutron in the g(9/2) and protons in the f(7/2) and f(5/2) spin-orbit partner orbitals. This interaction could result in a weakening of magicity in (78)Ni(50). 相似文献
89.
D. Rudolph R. Hoischen M. Hellström S. Pietri Zs. Podolyák P. H. Regan A. B. Garnsworthy S. J. Steer F. Becker P. Bednarczyk L. Cáceres P. Doornenbal J. Gerl M. Górska J. Grebosz I. Kojouharov N. Kurz W. Prokopowicz H. Schaffner H. J. Wollersheim L. -L. Andersson L. Atanasova D. L. Balabanski M. A. Bentley A. Blazhev C. Brandau J. R. Brown C. Fahlander E. K. Johansson A. Jungclaus 《The European Physical Journal A - Hadrons and Nuclei》2008,36(2):131-138
The fragmentation of a 550MeV/u primary beam of 58Ni on a 9Be target has been used to measure time- and energy-correlated γ decays following the implantation of event-by-event discriminated
secondary fragments into a 9Be stopper plate. A new isomeric γ decay with T
1/2 = 14(
) ns and E
γ = 646.2(2) keV is observed and attributed to the decay of the yrast 3/2- state in 53
27Co26 . This short-lived isomeric state has been populated by means of nuclear reactions during the stopping process of the secondary
fragments. The experimental findings are discussed in the framework of large-scale spherical shell model calculations in conjunction
with isospin symmetry-breaking residual interactions for the A = 53 , T
z = ±1/2 mirror nuclei 53Co and 53Fe . 相似文献
90.
Osterhoff J Popp A Major Z Marx B Rowlands-Rees TP Fuchs M Geissler M Hörlein R Hidding B Becker S Peralta EA Schramm U Grüner F Habs D Krausz F Hooker SM Karsch S 《Physical review letters》2008,101(8):085002
Laser-driven, quasimonoenergetic electron beams of up to approximately 200 MeV in energy have been observed from steady-state-flow gas cells. These beams emitted within a low-divergence cone of 2.1+/-0.5 mrad FWHM display unprecedented shot-to-shot stability in energy (2.5% rms), pointing (1.4 mrad rms), and charge (16% rms) owing to a highly reproducible gas-density profile within the interaction volume. Laser-wakefield acceleration in gas cells of this type provides a simple and reliable source of relativistic electrons suitable for applications such as the production of extreme-ultraviolet undulator radiation. 相似文献