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101.
A modified criterion of the SM perturbative consistency is proposed. It is based on the analytic properties of the two-loop SM running couplings. Under the criterion adopted, the Higgs mass up to 380 GeV might not give rise to strong coupling prior to the Planck scale. This means that the light Higgs boson is possibly preferred for reasons other than the SM perturbative consistency, i.e., for reasons beyond the SM. 相似文献
102.
J. Salgado E. Martinho I. F. Gonçalves 《Journal of Radioanalytical and Nuclear Chemistry》2004,260(2):317-320
The resonance neutron self-shielding factor, G
res, is required in neutron metrology and activation data analysis. In a previous paper, the authors have shown that a dimensionless
variable can be introduced which converts the dependence of G
res on the physical and nuclear properties of the material samples into an universal curve, valid for the isolated resonances
of any nuclide. This work presents a methodology based on the universal curve, which enables to calculate G
res for a group of isolated resonances by weighting its individual contributions. A good agreement was reached with results calculated
by the MCNP code and with experimental values for Mo foils and wires.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
103.
Microscopic petrified grains were collected from a mafic–ultramafic pipe, NE of Dreikeesh, NW Syria. The grains were identified as anthers/gynoecia in herb/grass flowers. Three of the grains showed evidence of magnetism, two slowly dissolved in concentrated HCl, and three microprobed grains showed a montmorillonitic composition. Iron originating from pyroxene was oxidized to magnetite. Released silica formed the mineral suite agate–chalcedony–opal. Warm/cold paleoclimatic fluctuations, occurring during late Pliocene–Holocene, depended on water vapor, CO2 production, and cinders in the atmosphere. Most of these were associated with changing volcanic/tectonic events. Fluctuations were controlled by heat reflected from the Earth's surface being absorbed by water vapor and CO2, which both re-reflected the heat back to the surface, thus, raising the temperature. This cycle was repeated several times during late Pliocene–Holocene. 相似文献
104.
105.
The frequency or dispersion relation for the least‐squares mixed formulation of the shallow‐water equations is analysed. We consider the use of different approximation spaces corresponding to co‐located and staggered meshes, respectively. The study includes the effect of Coriolis, and the dispersion properties are compared analytically and graphically with those of the mixed Galerkin formulation. Numerical solutions of a test problem to simulate slow Rossby modes illustrate the theoretical results. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
106.
N. Fazeli F. Afshar Taromi 《Journal of polymer science. Part A, Polymer chemistry》2003,41(1):135-142
The basis of the two‐step in–in method is as follows: star polymers with poly(divinyl benzene) cores, synthesized by the arm‐first method, include many unreacted double bonds in their core, and these double bonds can be attacked by the carbanions of some monomers such as styrene and dienes. In this work, linear polyisoprene chains were used to attack the double bonds existing in the poly(divinyl benzene) cores of polystyrene star polymers, so that a heteroarm star polymer with polystyrene and polyisoprene arms was synthesized. It was later well characterized with size exclusion chromatography, light scattering, viscometry, UV spectroscopy, dynamic mechanical thermal analysis, and 1H NMR. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 135–142, 2003 相似文献
107.
Kurenkov V. F. Zhelonkina T. A. Ryabysheva N. A. Lobanov F. I. 《Russian Journal of Applied Chemistry》2003,76(8):1310-1314
The influence of single- and double-charged cations on degradation of metal 2-acrylamido-2-methylpropanesulfonate-N-vinylpyrrolidine copolymers in aqueous solutions in the presence of potassium peroxodisulfate, K2S2O8, at 50 and 70°C was studied by viscosimetry. 相似文献
108.
The features of anthracite oxidation as influenced by temperature and time were determined. Physicochemical and sorption characteristics of the resulting cation exchanger were studied. 相似文献
109.
F. Ramsteiner 《Polymer Testing》1996,15(6):573-584
It is shown that CT (compact tension) specimens known from fracture mechanics are adequate to study the strength of interfaces between polymers. The interface is coplanar with the initial notch. The capability of this method is demonstrated by quantifying: (a) the healing procedure of cracks in polystyrene; (b) by elaborating the influence of powders on the welding process in polystyrene; (c) by measuring the strength of interfaces between the different polymers SAN, PMMA, HIPS, PS, PC, and (d) by characterising the influence of a compatibilizer in the interface between PE and HIPS. 相似文献
110.