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211.
Let F be a non-Archimedean local field with finite residue field. Let n be a positive integer, let G = GLn(F), and let D be a central F-division algebra of dimension n2. The Jacquet-Langlands correspondence gives a canonical bijection D from the set of equivalence classes of irreducible, smooth, essentially square-integrable representations of G to the set of equivalence classes of irreducible smooth representations of D![![times;. We give a necessary and sufficient condition, in terms of dim, for an irreducible smooth representation of D× to be of the form D, for an irreducible supercuspidal representation of G, thereby solving an old problem. This relies on the explicit classification of the irreducible smooth representations of G and the parallel classification of the irreducible representations of D×.This paper was written while the first-named author was visiting, and partly supported by, Université de Paris-Sud. At that time, the second-named author was enjoying the hospitality of the IHES, during a stay at the CNRS granted by Université de Paris-Sud; he would like to thank all those institutions. The work was also partially supported by EU network Arithmetical Algebraic Geometry.Mathematics Subject Classification (2000): 22E50 相似文献
212.
Inorganic/organic mesostructure directed synthesis of wire/ribbon-like polypyrrole nanostructures 总被引:7,自引:0,他引:7
We report here a simple strategy for the synthesis of wire/ribbon-like polypyrrole nanostructures using lamellar inorganic/organic mesostructures as templates which were formed during polymerization between surfactant cations and oxidising anions and which were degraded automatically after polymerization. 相似文献
213.
The solvation parameter model is used to identify suitable chromatographic models for estimating the octanol-water partition coefficient for neutral compounds of varied structure by reversed-phase liquid chromatography. The stationary phase Supelcosil LC-ABZ with methanol-water mobile phases affords a series of suitable correlation models for estimating the octanol-water partition coefficient (log KOW) under isocratic and gradient elution conditions. Isocratic separations with mobile phase compositions containing from about 25 to 40% (v/v) methanol provide the most accurate results for log KOW values in the range -0.1 to 4.0. Gradient separations programmed from 5 to 100% (v/v) methanol are suitable for faster separations of compounds with large log KOW values. The standard error in the estimate for the regression models of the predicted log KOW values against literature values are 0.135 log units for the 30% (v/v) methanol-water isocratic system and 0.263 log units for the methanol-water gradient system. Isocratic retention factors predicted from two gradient separations with gradient times of 15 and 45 min afford a poorer fit for the correlation models between log KOW and the estimated retention factors than that of either the above isocratic and gradient models. Plots of the retention factor (log k) as a function of mobile phase composition are generally non-linear. Values of log kw obtained by non-linear extrapolation to a volume fraction of 0% (v/v) methanol do not afford a useful model for estimating log KOW. 相似文献
214.
The join semi-lattice of faces of an n-cube has a rich
structure. In considering generalizations of these structures we are led to looking at interval
algebras constructed using Boolean filters. We look at the structure of these algebras and
their automorphism groups.Dedicated to the memory of Gian-Carlo Rota 相似文献
215.
[reaction: see text] Aryl alpha,beta-unsaturated ketones and aldehydes were synthesized, in moderate to excellent yields, with use of dimethylammonium dimethyl carbamate (DIMCARB) as a recyclable reaction medium and as a catalyst. 相似文献
216.
E. Galichet F. Gulminelli D. C. R. Guinet M. F. Rivet J. F. Lecolley R. Bougault G. Auger B. Borderie B. Bouriquet A. Buta J. L. Charvet A. Chbihi J. Colin D. Cussol R. Dayras D. Durand J. D. Frankland B. Guiot S. Hudan P. Lautesse F. Lavaud N. Le Neindre O. Lopez L. Manduci J. Marie L. Nalpas J. Normand M. Pârlog P. Paw lowski E. Plagnol E. Rosato J. C. Steckmeyer B. Tamain A. Van Lauwe E. Vient C. Volant J. P. Wieleczko INDRA Collaboration 《The European Physical Journal A - Hadrons and Nuclei》2003,18(1):75-86
The transport properties of the 36Ar +58Ni system at
measured with the INDRA array, are studied within the BNV kinetic equation. A general protocol of comparison between the N-body experimental fragment information and the one-body distribution function is developed using global variables, with a special focus on charge density. This procedure avoids any definition of sources and any use of an afterburner in the simulation. We shall discuss the feasibility of such an approach and the distortions induced by the finite detection efficiency and the completeness requirements of the data selection. The sensitivity of the different global observables to the macroscopic parameters of the effective nuclear interaction will be studied in detail.Received: 21 January 2003, Published online: 5 August 2003PACS:
25.70.-z Low and intermediate energy heavy-ion reactions - 24.10.-i Nuclear reaction models and methodsN. Le Neindre: Permanent address: Institut de Physique Nuclaire, IN2P3-CNRS, F-91406 Orsay cedex, France. 相似文献
217.
Colin Adams 《Geometriae Dedicata》2003,99(1):47-60
A construction is presented which can be utilized to prove incompressibility of boundary in a 3-manifold W. One constructs a new 3-manifold DW by doubling W along a subsurface in its boundary. If DW is hyperbolic, and if W has compressible boundary, then DW must have a longitude of 'length' less than 4. This can be applied to show that an arc that is a candidate for an unknotting tunnel in a 3-manifold cannot be an unknotting tunnel. It can also be used to show that a 'tubed surface' is incompressible. For knot and link complements in S
3, and an unknotting tunnel, DW is almost always hyperbolic. Empirically, this construction appears to provide a surprisingly effective procedure for demonstrating that specific arcs are not unknotting tunnels. 相似文献
218.
This article gives Bohr-Sommerfeld rules for semiclassical completely integrable systems with two degrees of freedom with non-degenerate singularities (Morse-Bott singularities) under the assumption that the energy level of the first Hamiltonian is non-singular. The more singular case of focus-focus singularities was treated in previous works by San V? Ngc. The case of one degree of freedom has been studied by Colin de Verdière and Parisse.The results are applied to some famous examples: the geodesics of the ellipsoid, the 1:2-resonance, and Schrödinger operators on the sphere S2. A numerical test shows that the semiclassical Bohr-Sommerfeld rules match very accurately the “purely quantum” computations. 相似文献
219.
Ronald L. Graham Jeffrey C. Lagarias Colin L. Mallows Allan R. Wilks 《Journal of Number Theory》2003,100(1):1-45
Apollonian circle packings arise by repeatedly filling the interstices between mutually tangent circles with further tangent circles. It is possible for every circle in such a packing to have integer radius of curvature, and we call such a packing an integral Apollonian circle packing. This paper studies number-theoretic properties of the set of integer curvatures appearing in such packings. Each Descartes quadruple of four tangent circles in the packing gives an integer solution to the Descartes equation, which relates the radii of curvature of four mutually tangent circles: . Each integral Apollonian circle packing is classified by a certain root quadruple of integers that satisfies the Descartes equation, and that corresponds to a particular quadruple of circles appearing in the packing. We express the number of root quadruples with fixed minimal element −n as a class number, and give an exact formula for it. We study which integers occur in a given integer packing, and determine congruence restrictions which sometimes apply. We present evidence suggesting that the set of integer radii of curvatures that appear in an integral Apollonian circle packing has positive density, and in fact represents all sufficiently large integers not excluded by congruence conditions. Finally, we discuss asymptotic properties of the set of curvatures obtained as the packing is recursively constructed from a root quadruple. 相似文献
220.