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11.
A recent experimental analysis suggested to represent the X(3872) -resonance as a c
[`(c)] \bar{{c}} 11
D
2 state but this attribution is being hotly debated. We calculate the mass values for that state by means of a previously studied
constituent-quark model. The different contributions of the model Hamiltonian to the total mass are also explicitly shown. 相似文献
12.
13.
Andrés Vásquez Quintero Danick Briand Nico F. de Rooij 《Journal of Polymer Science.Polymer Physics》2013,51(8):668-679
This study presents the mechanical characterization of the dry film photoresist PerMX and its adhesion properties when laminated onto Kapton® E (PI) and Melinex® ST506 (PET). Additionally, the processing temperature, the adhesion strength, and the neutral plane position are investigated and optimized. A relatively low-temperature (85 °C) process is developed to protect the integrity of the polymers with low glass transition temperature and reduce the thermal mismatch stress. Reduction in processing temperature led to a decrement in the adhesion strength. To counteract this unwanted effect, surface treatments (oxygen plasma) are performed on the polymer surface before lamination. Using the latter techniques, adhesion of PerMX to PET (hard bake: 1 h at 85 °C) is increased from 0.07 to 0.26 N mm−1 (variation of 270%). Finally, the mechanical robustness is investigated and increased by tuning the position of the neutral plane, after 50,000 bending cycles and a radius of curvature of 2.5 mm. © 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013 相似文献
14.
We examined the influence of the gas flow-rate, microwave power and trichloroethylene concentration on the destruction of
trichloroethylene with a system based on a microwave helium plasma operating at atmospheric pressure. Based on the experimental
results obtained, the proposed system allows input concentrations of C2HCl3 in the ppmv range to be reduced to output concentrations in the ppbv range (i.e. virtually quantitative destruction) by using
a microwave plasma power below 1000 W. High helium flow-rates and C2HCl3 concentrations allow energy efficiency values above 600 g/kW h to be obtained. Analyses of the output gases by gas chromatography
and species present in the plasma by optical emission spectroscopy confirmed the negligible presence of halogen compounds
resulting from the destruction of C2HCl3, and that of CCl4 and C2Cl4 as the sole chlorine species exceeding levels of 30 ppbv. Gaseous by-products consisted mainly of CO2, NO and N2O in addition to Cl2 traces. 相似文献
15.
Summary. We describe traveling waves in a basic model for three-dimensional water-wave dynamics in the weakly nonlinear long-wave
regime. Small solutions that are periodic in the direction of translation (or orthogonal to it) form an infinite-dimensional
family. We characterize these solutions through spatial dynamics, by reducing a linearly ill-posed mixed-type initial-value
problem to a center manifold of infinite dimension and codimension. A unique global solution exists for arbitrary small initial
data for the two-component bottom velocity, specified along a single line in the direction of translation (or orthogonal to
it). A dispersive, nonlocal, nonlinear wave equation governs the spatial evolution of bottom velocity.
Received July 20, 2001; accepted November 5, 2001 相似文献
16.
We investigate the electric-pulse-induced resistance switching in manganite systems. We find a "complementarity" effect where the contact resistance of electrodes at opposite ends show variations of opposite sign and is reversible. The temperature dependence of the magnitude of the effect reveals a dramatic enhancement at a temperature T*, below the metal-insulator transition. We qualitatively capture these features with a theoretical model, providing evidence for the physical mechanism of the resistance switching. We argue that doping control of the electronic state of the oxide at the interfaces is the mechanism driving the effect. 相似文献
17.
Quintero A Fabbro R Maillo M Barrios M Milano MB Fernández A Williams B Michelangeli F Rangel HR Pujol FH 《Natural product research》2011,25(16):1565-1569
The primary objective of this study was to search for natural products capable of inhibiting hepatitis B virus (HBV) replication. The research design, methods and procedures included testing hydro-alcoholic extracts (n?=?66) of 31 species from the Venezuelan Amazonian rain forest on the cell line HepG2 2.2.15, which constitutively produces HBV. The main outcomes and results were as follows: the species Euterpe precatoria, Jacaranda copaia, Jacaranda obtusifolia, Senna silvestris, Warscewiczia coccinea and Vochysia glaberrima exerted some degree of inhibition on HBV replication. The leaves of W. coccinea showed a significant antiviral activity: 80% inhibition with 100?μg?mL?1 of extract. This extract also exerted inhibition on covalently closed circular deoxyribonucleic acid (cccDNA) production and on HIV-1 replication in MT4 cells (more than 90% inhibition with 50?μg?mL?1 of extract). Initial fractionation using organic solvents of increasing polarity and water showed that the ethanol fraction was responsible for most of the antiviral inhibitory activities of both the viruses. It was concluded that Warscewiczia coccinea extract showed inhibition of HBV and HIV-1 replication. Bioassay-guided purification of this fraction may allow the isolation of an antiviral compound with inhibitory activity against both viruses. 相似文献
18.
Fernando Díaz Andrs Benassi Mariano Quintero Griselda Polla Eleonora Freire Ricardo Baggio 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(7):o222-o225
In the title racemic hemihydrated solvatomorph of carvedilol (carv), C24H26N2O4·0.5H2O, the asymmetric unit contains two independent organic moieties and one water molecule. Within this 2(carv)·H2O unit, the molecular components are strongly linked by hydrogen bonds and the unit acts as the basic building block for the crystal structure. Interactions parallel to (10) generate hydrogen‐bonded layers which are further linked by much weaker C—H...N/O interactions. The conformations of the organic molecules, as well as the hydrogen‐bonding interactions connecting them, are compared with other related structures in the literature. 相似文献
19.
José Rául Quintero 《Journal of Dynamics and Differential Equations》2003,15(1):125-142
We study nonlinear orbital stability and instability of the set of ground state solitary wave solutions of a one-dimensional Boussinesq equation or one-dimensional Benney–Luke equation. It is shown that a solitary wave (traveling wave with finite energy) may be orbitally stable or unstable depending on the range of the wave's speed of propagation. 相似文献
20.
Summary In this note we use Theorem 2.4 in<span lang=EN-US style='font-size:10.0pt;mso-ansi-language:EN-US'>[1]to give a very short
proof of a recent result due to M. Bognár (Theorem A in [3]). We also prove that Bognár's result is in fact equivalent to
the classical Hahn-Mazurkiewicz Theorem. Finally we give generalizations in the non-compact setting. 相似文献