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191.
A note on the nucleolus and the kernel of the assignment game 总被引:1,自引:0,他引:1
There exist coalitional games with transferable utility which have the same core but different nucleoli. We show that this cannot happen in the case of assignment games. Whenever two assignment games have the same core, their nucleoli also coincide. To show this, we prove that the nucleolus of an assignment game coincides with that of its buyer–seller exact representative.I am grateful to C. Rafels and to the referees for their comments. Institutional support from research grants BEC 2002-00642 and SGR2001–0029 is also acknowledged. 相似文献
192.
Maurizio?ChiccoEmail author Marina?VenturinoEmail author 《Annali di Matematica Pura ed Applicata》2004,183(2):241-259
We prove some a priori inequalities for solutions of mixed boundary-value problems for a class of divergence form elliptic equations with discontinuous and unbounded coefficients in unbounded domains. Mathematics Subject Classification (2000) 35J25 相似文献
193.
Evgenia G. Matveeva Marina I. Nelen Oleg I. Lobanov Alexander P. Savitsky 《Journal of fluorescence》2003,13(1):79-88
The antigen-antibody interaction between coproporphyrin I and anti-coproporphyrin antibodies was studied by a fluorescence method in water and a reverse micellar system: n-octane/Aerosol OT. Coproporphyrin fluorescence was quenched, and coproporphyrin emission maximum was shifted to the long-wavelength region after binding to the antibodies or Fab-fragments. The mechanism of this quenching is static, most probably, by a tryptophan residue (or maybe lysine or methionine). Apparent dynamic quenching, in this case, arises from protein backbone motion. A special kind of antibody Fab-Fab dimerization was proposed. 相似文献
194.
195.
A selective, sensitive, and accurate high-performance liquid chromatographic method for determination of diltiazem in plasma samples has been developed and validated. The effects of mobile phase composition, buffer concentration, mobile phase pH, and concentration of organic modifiers on retention of diltiazem and internal standard were investigated. Solid-phase and liquid–liquid extraction were examined and proposed for isolation of the drug and elimination of endogenous plasma interferences. A 5 m Lichrocart Lichrospher 60 RP-select B chromatographic column was used; the mobile phase was acetonitrile–0.025 mol L–1 KH2PO4 (pH 5.5), 35:65 ( v / v) at a flow-rate of 1.5 mL min–1. The detection wavelength was 215 nm. The calibration plots were linear in the concentration range 20.0–500.0 ng mL–1. The method has been implemented to monitor diltiazem levels in patient samples. 相似文献
196.
197.
Roman Luboradzki Janusz Lipowski Yurii A. Simonov Marina S. Fonari Edward V. Ganin Arkadii A. Yavolovskii 《Journal of inclusion phenomena and macrocyclic chemistry》2001,40(1-2):59-65
The X-ray crystal structures of two closely related molecular complexes of 15-crown-5 and benzo-15-crown-5 with 3,4-diamino-1,2,5-oxadiazole are reported (I and II). Both complexes are of 1:1 stoichiometry with the host–guest alternation in the infinitechains formed due to the unsymmetrical H-bonding patterns between the components. Crystals of I are monoclinic, P21/c, a = 7.856(3), b = 12.994(1), c = 16.033(1) , = 94.79(2)°, Z = 4, final R-factor is 0.0488. Crystals of II are orthorhombic, P212121, a = 8.260(4), b = 15.692(5),c = 13.955(7) , Z = 4, final R-factor is 0.0522. 相似文献
198.
In the assignment game framework, we try to identify those assignment matrices in which no entry can be increased without
changing the core of the game. These games will be called buyer-seller exact games and satisfy the condition that each mixed-pair
coalition attains the corresponding matrix entry in the core of the game. For a given assignment game, a unique buyer-seller
exact assignment game with the same core is proved to exist. In order to identify this matrix and to provide a characterization
of those assignment games which are buyer-seller exact in terms of the assignment matrix, attainable upper and lower core
bounds for the mixed-pair coalitions are found. As a consequence, an open question posed in Quint (1991) regarding a canonical
representation of a “45o-lattice” by means of the core of an assignment game can now be answered.
Received: March 2002/Revised version: January 2003
RID="*"
ID="*" Institutional support from research grants BEC 2002-00642 and SGR2001-0029 is gratefully acknowledged
RID="**"
ID="**" The authors thank the referees for their comments 相似文献
199.
Neven Strukan Marina Cindri Maja Dev
i Gerald Giester Boris Kamenar 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):e278-e279
The crystal and molecular structure of the title compound, (C4H12N)2[Mo6O19]·H2O, has been determined from X‐ray diffraction data. The polyoxoanion [Mo6O19]2? is built up from six distorted MoO6 octahedra sharing common edges and one common vertex at the central O atom, and has crystallographic m3m (Oh) symmetry. The cation has crystallographic 3m symmetry. 相似文献