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931.
An asynchronous parallel newton method 总被引:3,自引:0,他引:3
A parallel Newton method is described for the minimization of a twice continuously differentiable uniformly convex functionF(x). The algorithm generates a sequence {x
j
} which converges superlinearly to the global minimizer ofF(x). 相似文献
932.
W. Bell K. Braune G. Claesson D. Drijard M.A. Faessler H.G. Fischer H. Frehse R.W. Frey S. Garpman W. Geist P.C. Gugelot P. Hanke M. Heiden P.G. Innocenti T.J. Ketel E.E. Kluge G. Mornacchi Th. Walcher 《Physics letters. [Part B]》1982,112(3):271-276
The inclusive production of charged hadrons has been measured in αα and αp collisions at nucleon-nucleon c.m. energies (√snn)of 31 and 44 GeV, respectively, for transverse momenta pT up to 5 GeV/c in the central rapidity (y) region. at high pT the yields are consistent with being 4 times and 16 times highere than the ones in pp interactions at y=0, for αp and αα interactions, respectively. However, an enhancement over these factors, as expected from an earlier FNAL experiment, cannot be ruled out. 相似文献
933.
Ohne Zusammenfassung 相似文献
934.
Intraelemental relative photoelectron line intensities for 20 pure elements obtained under ultrahigh vacuum (5·10?9 torr) and high resolution with cleaned surfaces are presented. Theoretical and experimental aspects of relative photoelectron line intensities as well as other characteristics of significance to quantitative analysis are discussed. Experimental data are related to theoretical results and compared with other recent work. 相似文献
935.
Tri(1-cyclohepta-2,4,6-trienyl)phosphane, P(C7H7)3, and Tetra(1-cyclohepta-2,4,6-trienyl)phosphonium Tetrafluoroborate, [P(C7H7)4]BF4 The reaction of tris(trimethylsilyl)phosphane, P(SiMe3)3, with tropylium bromide, C7H7+Br?, in polar solvents such as dichloromethane or tetrahydrofuran gives P(C7H7)3 ( 1 ) and [P(C7H7)4]Br ( 2a ). According to the X-ray crystallographic structure determinations, all 1-cyclohepta-2,4,6-trienyl substituents are present in the boat conformation in both P(C7H7)3 ( 1 ) and the phosphonium salt, [P(C7H7)4]BF4 ( 2b ). The boat-shaped C7H7 rings are significantly more flattened if the phosphorus occupies the axial rather than the equatorial position at the ring substituent. Addition of a chalcogen to the lone pair at the central phosphorus atom of 1 leads to the chalcogena-phosphoranes EP(C7H7)3 (E = O ( 3a ), S ( 3b ), Se ( 3c )). The new 1-cyclohepta-2,4,6-trienyl-phosphorus compounds 1, 2 b and 3a–c were characterized by their 1H, 13C, and 31P NMR spectra in C6D6 solution. 相似文献
936.
A method for partitioning topologically chiral knots into mutually heterochiral classes has been developed, based on the principle that for such knots there exist no diagrams whose vertex-bicolored graphs are composed of equivalent black and white subgraphs. The method, which introduces the concept ofwrithe profiles, is successfully applied to alternating as well as non-alternating prime and composite knots, and works in cases where the Jones and Kauffman polynomials fail to recognize the knot's chirality. It is shown that writhe profiles are sensitive indicators of diagram similarity. 相似文献
937.
938.
939.
Extracts with tri-n-octylammonium chlorocomplexes of Sn(IV) of various compositions, included the N-deuterated compounds, were prepared and investigated by IR spectroscopy and conductivity measurements. Three Sn(IV) complexes were found: (TOAH+)2SnCl62? (2:1-complex), TOAH+SnCl5? (1:1-complex) and a complex with the stoichiometric ratio TOA:Sn(IV) > 2. The cation of the latter contains the groups (TOAH…Cl…HTOA)+ and TOAH+ and that species is supposed to be a 3:1-complex (TOAH…Cl…HTOA)+TOAH+SnCl62?. 相似文献
940.