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1.
Francis K. Bell 《Journal of Graph Theory》2003,43(2):137-149
It is shown that, if t is an integer ≥3 and not equal to 7 or 8, then there is a unique maximal graph having the path Pt as a star complement for the eigenvalue ?2. The maximal graph is the line graph of Km,m if t = 2m?1, and of Km,m+1 if t = 2m. This result yields a characterization of L(G ) when G is a (t + 1)‐vertex bipartite graph with a Hamiltonian path. The graphs with star complement Pr ∪ Ps or Pr ∪ Cs for ?2 are also determined. © 2003 Wiley Periodicals, Inc. J Graph Theory 43: 137–149, 2003 相似文献
2.
Anna Arkhireeva John N. Hay Jackie M. Lane Miguel Manzano Helen Masters Wilberforce Oware Steve J. Shaw 《Journal of Sol-Gel Science and Technology》2004,31(1-3):31-36
The synthesis of ORganically MOdified SILica (ORMOSIL) particles has been carried out using both the hydrolytic and non-hydrolytic sol-gel routes. The hybrid (nano)composites are organically modified with an alkyl or aryl group covalently bonded to silicon. Hybrids have been synthesised in an aqueous sol-gel process by a modified Stöber route, producing spherical nanoparticles with diameters in the range 50–300 nm. The size of the particles can be controlled by control of certain reaction parameters. Smaller ormosil nanoparticles can be synthesised by a base-catalysed emulsion polymerisation route, by varying the type and concentration of surfactant and precursor feed rate. In this case, particles in the size range 3.5–10 nm can be obtained. Hybrids have been synthesised from hyperbranched polyesters by encapsulation in a silica matrix using the hydrolytic sol-gel route. Optimisation of the reaction conditions allows the hybrids to be produced as isolated sub-micron spherical particles. Ormosil particles have also been synthesised using the non-hydrolytic sol-gel route, which may lead to products of different morphologies because of the different polarity of the reaction medium. Different reaction conditions were studied in order to optimise the size and shape of the particles, including choice of solvent, use of surfactants and addition of polystyrene. Dimethylsulfoxide acts as a novel oxygen donor for the catalyst-free formation of colourless silsesquioxanes. 相似文献
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Daria E. Lonsdale Geoffrey Johnston‐Hall Amanda Fawcett Craig A. Bell Carl N. Urbani Michael R. Whittaker Michael J. Monteiro 《Journal of polymer science. Part A, Polymer chemistry》2007,45(16):3620-3625
In this work, we propose that retardation in vinyl acetate polymerization rate in the presence of toluene is due to degradative chain transfer. The transfer constant to toluene (Ctrs) determined using the Mayo method is equal to 3.8 × 10?3, which is remarkably similar to the value calculated from the rate data, assuming degradative chain transfer (2.7 × 10?3). Simulations, including chain‐length‐dependent termination, were carried out to compare our degradative chain transfer model with experimental results. The conversion–time profiles showed excellent agreement between experiment and simulation. Good agreement was found for the Mn data as a function of conversion. The experimental and simulation data strongly support the postulate that degradative chain transfer is the dominant kinetic mechanism. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3620–3625, 2007 相似文献
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This report focuses on a theoretical study of the cobalt-cabon bond activation mechanism in Vitamin B12, its co enzyme complexes, and model compounds such as cobalamins (Cbl), cobaloximes and cobalt porphyrins. In particular, emphasis is placed on the nucleotide loop and its role in the base on and base off mechanism. 相似文献
7.
The regression problem in learning theory is investigated with least square Tikhonov regularization schemes in reproducing
kernel Hilbert spaces (RKHS). We follow our previous work and apply the sampling operator to the error analysis in both the
RKHS norm and the L2 norm. The tool for estimating the sample error is a Bennet inequality for random variables with values in Hilbert spaces.
By taking the Hilbert space to be the one consisting of Hilbert-Schmidt operators in the RKHS, we improve the error bounds
in the L2 metric, motivated by an idea of Caponnetto and de Vito. The error bounds we derive in the RKHS norm, together with a Tsybakov
function we discuss here, yield interesting applications to the error analysis of the (binary) classification problem, since
the RKHS metric controls the one for the uniform convergence. 相似文献
8.
We complete our previous(1, 2) demonstration that there is a family of new solutions to the photon and Dirac equations using spatial and temporal circles and four-vector behaviour of the Dirac bispinor. We analyse one solution for a bound state, which is equivalent to the attractive two-body interaction between a charged point particle and a second, which remains at rest. We show this yields energy and angular momentum eigenvalues that are identical to those found by the usual method of solving of the Dirac equation,(4) including fine structure. We complete our previous derivation(2) of QED from a set of rules for the two-body interaction and generalise these. We show that QED may be decomposed into a two-body interaction at every point in spacetime. 相似文献
9.
Capacity Constrained Transit Assignment with Common Lines 总被引:1,自引:0,他引:1
Fumitaka Kurauchi Michael G. H. Bell Jan-Dirk Schmöcker 《Journal of Mathematical Modelling and Algorithms》2003,2(4):309-327
This paper proposes the use of absorbing Markov chains to solve the capacity constrained transit network loading problem taking
common lines into account. The approach handles congested transit networks, where some passengers will not be able to board
because of the absence of sufficient space. The model also handles the common lines problem, where choice of route depends
on frequency of arrivals. The mathematical formulation of the problem is presented together with a numerical example.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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