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61.
62.
A simple construction for the Fischer-Griess monster group 总被引:2,自引:0,他引:2
J. H. Conway 《Inventiones Mathematicae》1985,79(3):513-540
63.
Let the lattice Λ have covering radiusR, so that closed balls of radiusR around the lattice points just cover the space. The covering multiplicityCM(Λ) is the maximal number of times the interiors of these balls overlap. We show that the least possible covering multiplicity
for ann-dimensional lattice isn ifn≤8, and conjecture that it exceedsn in all other cases. We determine the covering multiplicity of the Leech lattice and of the latticesI
n, An, Dn, En and their duals for small values ofn. Although it appears thatCM(I
n)=2
n−1 ifn≤33, asn → ∞ we haveCM(I
n)∼2.089...
n
. The results have application to numerical integration. 相似文献
64.
Abbott T Akiba Y Beavis D Bloomer MA Bond PD Chasman C Chen Z Chu YY Cole BA Costales JB Crawford HJ Cumming JB Debbe R Engelage J Fung SY Grodzins L Gushue S Hamagaki H Hansen O Hayano RS Hayashi S Homma S Huang HZ Ikeda Y Juricic I Kang J Katcoff S Kaufman S Kimura K Kitamura K Kurita K Ledoux RJ Levine MJ Miake Y Morse RJ Moskowitz B Nagamiya S Olness J Parsons CG Remsberg LP Sakurai H Sarabura M Shor A Stankus P Steadman SG Stephans GS Sugitate T Tanaka M Tannenbaum MJ Torikoshi M 《Physical review letters》1991,66(12):1567-1570
65.
Summary A construction for sphere packings is introduced that is parallel to the anticode construction for codes. This provides a simple way to view Vardy's recent 20-dimensional sphere packing, and also produces packings in dimensions 22, 44–47 that are denser than any previously known.Oblatum 18-VII-1994 & 7-XII-1994 相似文献
66.
67.
John B. Conway Nathan S. Feldman 《Proceedings of the American Mathematical Society》1997,125(1):243-244
In this paper an easier proof is obtained of Alexandru Aleman's extension of an inequality of Axler and Shapiro for subnormal operators to the essential norm. The method is applied to show that a hyponormal operator whose essential spectrum has area zero must be essentially normal.
68.
B. E. Conway 《Journal of solution chemistry》1978,7(10):721-770
A critical examination is given of extra-thermodynamic methods for evaluation of properties of individual ions in solution. The ways in which such data may be applied, or are required in various problems concerning specific properties of electrolyte solutions and in the fields of kinetics, electrochemistry, colloid and interfacial chemistry, are outlined. Special attention is given to the problem of evaluation of individual ionic thermodynamic functions for the hydration of ions but, in some cases, corresponding data for nonaqueous solutions are available for discussion and are of interest in a comparative way. The reliability of the various methods is assessed and estimates of numerical values for various individual ionic functions are tabulated. The question of scales of individual ionic radii, on which some of the derived data depend, is also examined. The dependence of various properties for anions and for cations on ionic radius is discussed and data are plotted comparatively. It is shown that for most, but not all, properties, the values for anions are more sensitive to increasing ionic radius than are the values for cations. This behavior, as well as the exceptions, is of theoretical interest. The significance of ion-specific behavior at interfaces is considered and the importance of interactions between ions of like sign of charge is indicated.Presented at the Symposium on Electrolytes, University of Reading, September 13, 1977. 相似文献
69.
Leeuwenburgh MA Litjens RE Codee JD Overkleeft HS van der Marel GA van Boom JH 《Organic letters》2000,2(9):1275-1277
[formula: see text] Tributyltin radical mediated cyclization of carbohydrate-derived beta-(alkynyloxy)acrylates leading to highly functionalized cis- and trans-fused bicyclic ethers of various ring sizes is described. The efficacy of the radical cyclization is nicely illustrated in the iterative construction of a trans-fused tricyclic tetrahydropyran. 相似文献
70.