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51.
Sebastião da Costa Paolinelli Marco Antônio da Cunha André Barros Cota 《Journal of magnetism and magnetic materials》2008
The presence of shear bands in the deformed material before final annealing is very important for Goss and Cube textures formation in silicon steel [S.C. Paolinelli, M.A. Cunha, J. Magn. Magn. Mater. 255 (2003) pp. 379. [1]; J.T. Park, J.A. Szpunar, Acta Mater., 51 (2003) 3037. [2]]. The increase of the hot-band grain size can increase the number of shear bands, which favor the nucleation of these orientations. In this work, the effect of the hot band grain size variation, promoted by varying the hot rolling finishing temperature, on final structure and magnetic properties was investigated for 3% Si alloy. It was found that the increase of the hot-band grain size increases the occurrence of shear bands and promotes an increase of η fiber fraction and a reduction of γ fiber fraction, improving the magnetic induction. On the other hand, the final grain size is reduced when the hot-band grain size is larger than 190 μm, deteriorating the core loss values in spite of the texture benefits. The reduction of final grain size was explained by the increase of the number of nuclei at the beginning of the recrystallization caused by the increase of shear bands in the deformed material. 相似文献
52.
We prove that the correlations present in a multipartite quantum state have an operational quantum character even if the state is unentangled, as long as it does not simply encode a multipartite classical probability distribution. Said quantumness is revealed by the new task of local broadcasting, i.e., of locally sharing preestablished correlations, which is feasible if and only if correlations are stricly classical. Our operational approach leads to natural definitions of measures for quantumness of correlations. It also reproduces the standard no-broadcasting theorem as a special case. 相似文献
53.
Pabla?Aguirre Natalia?Mena Victoria?Tapia Miguel?Arredondo Marco?T?Nú?ezEmail author 《BMC neuroscience》2005,6(1):3
Background
Iron is necessary for neuronal function but in excess generates neurodegeneration. Although most of the components of the iron homeostasis machinery have been described in neurons, little is known about the particulars of their iron homeostasis. In this work we characterized the response of SH-SY5Y neuroblastoma cells and hippocampal neurons to a model of progressive iron accumulation. 相似文献54.
J. L. Bailly W. Bartl F. Bruyant W. M. Bugg C. Caso R. Contri H. Dibon R. Di Marco B. Epp A. Ferrando F. Fontanelli P. Girtler A. Gurfu E. L. Hart P. Herquet J. Hrubec Y. Iga E. Kisteney S. Kitamura J. M. Kohli H. Kohno J. C. Marin M. Markytan I. S. Mittra L. Montanet G. Neuhofer Y. Petrovykh R. Plano B. Poljakov P. Porth B. Powell B. Pylgroms T. Rodrigo A. H. Rogers J. Salicio S. Squarcia P. Stamer V. Stopchenko K. Sudhakar U. Trevisan C. Willmott T. Yamagata V. Yarba EHS-RCBC Collaboration Bombay-CERN-Genova-Innsbruck-Japan UG-Madrid-Mons-Rutgers-Serpukhov-Tennessee-Vienna Collaboration 《Zeitschrift fur Physik C Particles and Fields》1984,22(2):119-124
The intermediate and forward gamma detectors of EHS are used to reconstructπ°'s produced by 360 GeV/cpp interactions in the Rapid Cycling Bubble Chamber (RCBC). Using thepp forwardbackward symmetry, the inclusiveπ° production cross section is obtainedσ π°=(132±11) mb. The averageπ° multiplicity is determined as a function of the charged particle multiplicity. The (1?x) dependence is given for differentp T regions. 相似文献
55.
In the present paper, Electron Paramagnetic Resonance, Ionic Thermocurrents and photoluminescence (emission and excitation) measurements have been performed in crystals of manganese- doped NaCl which were exposured to room temperature X-irradiation. The results obtained indicate that the diffusion of the Mn2+ - cation vacancy dipoles, originally present in the quenched samples, is considerably enhanced by ionizing radiation leading to the formation of a second phase precipitate which appears to be related with the Suzuki phase of the manganese ions in the host NaCl, as revealed from the EPR and optical data. 相似文献
56.
57.
Marco Dall'Aglio Theodore P. Hill 《Journal of Mathematical Analysis and Applications》2003,281(1):346-361
For fair-division or cake-cutting problems with value functions which are normalized positive measures (i.e., the values are probability measures) maximin-share and minimax-envy inequalities are derived for both continuous and discrete measures. The tools used include classical and recent basic convexity results, as well as ad hoc constructions. Examples are given to show that the envy-minimizing criterion is not Pareto optimal, even if the values are mutually absolutely continuous. In the discrete measure case, sufficient conditions are obtained to guarantee the existence of envy-free partitions. 相似文献
58.
We present a multigrid algorithm to solve linear systems whose coefficient metrices belongs to circulant, Hartley or τ multilevel algebras and are generated by a nonnegative multivariate polynomial f. It is known that these matrices are banded (with respect to their multilevel structure) and their eigenvalues are obtained by sampling f on uniform meshes, so they are ill‐conditioned (or singular, and need some corrections) whenever f takes the zero value. We prove the proposed metod to be optimal even in presence of ill‐conditioning: if the multilevel coefficient matrix has dimension ni at level i, i = 1, … , d, then only ni operations are required on each iteration, but the convergence rate keeps constant with respect to N(n) as it depends only on f. The algorithm can be extended to multilevel Toeplitz matrices too. 相似文献
59.
A rigorous wave-theoretic approach to the Michelson-Morley (M-M) experiment is presented, with special emphasis on the Huygens' principle derivation of the laws of reflection by a moving mirror. A detailed discussion of the Lorentz-Fitzgerald contraction hypothesis (CH) is included. Several mistakes appearing in the standard textbook treatments of these issues are pointed out, and a number of related historical questions are considered. 相似文献
60.
We derive the Kramers equation, namely, the Fokker-Planck equation for an oscillator, from a completely deterministic picture. The oscillator is coupled to a “booster”, i.e., a deterministic system in a fully chaotic state, wherein diffusion is derived from the sensitive dependence of chaos on initial conditions and friction is a consequence of the linear response of the booster to the action exerted on it by the oscillator. To deal with the Hamiltonian nature of the system of interest and of its coupling to the booster, we extend the earlier theoretical derivation of macroscopic transport coefficients from deterministic dynamics. We show that the frequency of the oscillator can be tuned to the microscopic frequencies of the booster without affecting the canonical nature of the “macroscopic” statistics. The theoretical predictions are supported by numerical simulations. 相似文献