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131.
Z. S. Macedo M. E. G. Valerio J. F. de Lima 《Journal of Physics and Chemistry of Solids》1999,60(12):1283-1981
In this work, the thermoluminescence properties of synthetic crystals of doped calcite were studied. Samples were doped with Mn2+, Mg2+ or Sr2+, either individually or simultaneously with more than one of these impurities. TL glow curves, partial heating measurements, isometric curves, emission spectra and thermal treatment were performed, in order to investigate the role played by the impurities in the TL glow peaks of calcite. We conclude that the crystals doped with Mn2+ show five TL peaks with emission spectra due only to the Mn2+. The relative intensity of these peaks is closely related to the other divalent dopant added in the solution (Sr2+ or Mg2+). These results suggest that although Sr2+ and Mg2+ act as TL activators stabilising slightly different electron traps, they are not directly connected to the Mn2+ luminescence centre. 相似文献
132.
Michele Battezzati Giuseppe Figari Camilla Costa Valerio Magnasco 《Chemical physics letters》2008,463(1-3):258-262
A self-consistent theory of the linear response previously developed by one of us is applied to the dipole–dipole dispersion interaction of two ground state H atoms in the united atom (He) limit, using a Sellmeier representation of the polarizability in terms of pseudostates. Numerical calculations show that a truncated 12-term expansion out of the N = 22 H(1s) dipole pseudospectrum built from STOs with orbital exponent c = 0.985 gives a result exceeding by no more than 5% the variational result for the He dispersion energy. 相似文献
133.
A quasi-geostrophic intermediate complexity model of the mid-latitude atmospheric circulation is considered, featuring simplified baroclinic conversion and barotropic convergence processes. The model undergoes baroclinic forcing towards a given latitudinal temperature profile controlled by the forced equator-to-pole temperature difference TE. As TE increases, a transition takes place from a stationary regime-Hadley equilibrium-to a periodic regime, and eventually to a chaotic regime where evolution takes place on a strange attractor. The attractor dimension, metric entropy, and bounding box volume in phase space have a smooth dependence on TE, which results in power-law scaling properties. Power-law scalings with respect to TE are detected also for the statistical properties of global physical observables — the total energy of the system and the averaged zonal wind. The scaling laws, which constitute the main novel result of the present work, can be thought to result from the presence of a statistical process of baroclinic adjustment, which tends to decrease the equator-to-pole temperature difference and determines the properties of the attractor of the system. The self-similarity could be of great help in setting up a theory for the overall statistical properties of the general circulation of the atmosphere and in guiding-on a heuristic basis-both data analysis and realistic simulations, going beyond the unsatisfactory mean field theories and brute force approaches. A leading example for this would be the possibility of estimating the sensitivity of the output of the system with respect to changes in the parameters. 相似文献
134.
Quantum cryptography protocols robust against photon number splitting attacks for weak laser pulse implementations 总被引:1,自引:0,他引:1
We introduce a new class of quantum key distribution protocols, tailored to be robust against photon number splitting (PNS) attacks. We study one of these protocols, which differs from the original protocol by Bennett and Brassard (BB84) only in the classical sifting procedure. This protocol is provably better than BB84 against PNS attacks at zero error. 相似文献
135.
Singly Periodic Costa Surfaces 总被引:1,自引:0,他引:1
Global Weierstrass representations are derived for completeminimal surfaces obtained by substituting the planar end ofthe Costa surface by Scherk ends. This gives rise to singlyperiodic examples, of which the fundamental piece is provedto be embedded by a simple geometric technique. This techniquecan be generalised for embeddedness proof of future examplesof the same nature. 相似文献
136.
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138.
Marinopoulos AG Reining L Olevano V Rubio A Pichler T Liu X Knupfer M Fink J 《Physical review letters》2002,89(7):076402
We determined the anisotropic dielectric response of graphite by means of time-dependent density-functional theory and high-resolution valence electron energy-loss spectroscopy. The calculated loss function was in very good agreement with the experiment for a wide range of momentum-transfer orientations with respect to the graphitic basal planes, provided that local-field effects were included in the response. The calculations also showed strong effects of the interlayer Coulomb interaction on the total pi+sigma plasmon. This finding must be taken into account for the explanation of recent loss spectra of carbon nanotube materials. 相似文献
139.
Coupled Multiscale Simulation and Optimization in Nanoelectronics project isaMarie Curie RTN supported by the European Commission within the 6th Framework Research Programme of the EU. The COMSON project is run by a Consortium whose multiple aims are: to build an experimental software Demonstrator Platform (DP) for coupled simulation of devices, interconnects, circuits, EM fields and thermal effects (one single framework for simulation tool, optimisation in compound design space); to provide an e-learning platform to be used as an inter and extra consortium transfer of knowledge (ToK) infrastructure; to provide a collaborative virtual work environment (CWE) to be used both for industrial activities and training. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
140.
Journal of Statistical Physics - Linear response theory, originally formulated for studying how near-equilibrium statistical mechanical systems respond to small perturbations, has developed into a... 相似文献