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161.
162.
Davide Franco 《Geometriae Dedicata》2000,81(1-3):33-52
Extending a result of Manivel, we prove the following: THEOREM. Suppose $\sum\limits_i {b_i \geqslant } \sum\limits_i {a_i } + n$ and $$\sum\limits_i {b_i } [n + d_i d_i - 1] \geqslant \sum\limits_i {a_i } [n + l_i l_i - 1] + n.$$ Then the kernel E(d) of the general morphism: $$\mathop \oplus \limits_{i = 1}^v (Bi \otimes O_{P^n } (d_i )) \to \mathop \oplus \limits_{j = 1}^v (A_j \otimes O_{P^n } (l_i ))$$ (l 1>...>l s>d 1>...>d v) is a globally generated vector bundle, except for at most finitely many sets $\left\{ {b_i ,a_i } \right\}$ . 相似文献
163.
164.
J. V. Pinto M. M. Cruz R. C. da Silva N. Franco A. Casaca E. Alves M. Godinho 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,55(3):253-260
The magnetic and electrical properties of Co-implanted
single crystalline TiO2 rutile are presented. For fluences of
the order of 1017 cm-2 and implantation energy of 150
keV the maximum atomic concentration of cobalt is 13 at% at a depth
of 65 nm from the surface. The as implanted single crystals exhibit
superparamagnetic behaviour attributed to the formation of nanosized
cobalt clusters. After annealing at 1073 K an anisotropic
ferromagnetic behaviour emerges with the easy magnetization axis
lying in the (001) plane of rutile. The ferromagnetic behaviour is
associated with oriented cobalt aggregates. Electrical conductivity
of the implanted samples annealed in vacuum also exhibits
anisotropic behaviour at low temperatures, but no magnetoresistive
effects were detected. 相似文献
165.
Entangled two-photon generalized binomial states of the electromagnetic field in two separate cavities are considered. The
nonlocal properties of this entangled field state are analyzed by studying the electric field correlations between the two
cavities. A Bell’s inequality violation is obtained using an appropriate dichotomic cavity operator that is, in principle,
measurable.
The text was submitted by the authors in English. 相似文献
166.
Giovanna Bruni Vittorio Berbenni Franco Sartor Chiara Milanese Alessandro Girella Dionigio Franchi Amedeo Marini 《Journal of Thermal Analysis and Calorimetry》2012,108(1):235-241
In this work, thermoanalytical, diffractometry, and microscopy measurements have been performed in order to characterize the
effect of high energy milling on a drug active in the migraine prophylaxis and smoke cessation. We can assert that the mechanical
treatment induces only a partial amorphisation of the solid phase, in particular it reduces the crystal order by producing
lattice defects which propagate from the surface to the bulk crystal. For this reason, the DSC is able to detect the presence
of ordered solid, while the powder X-ray diffractometry, because of its low penetration depth, does not reach the crystalline
core of the particles. 相似文献
167.
An infinite-parameter family of discontinuous area-preserving maps is studied, using geometrical methods. Necessary and sufficient conditions are determined for the existence of some bounding invariant sets, which guarantee global stability. It is shown that under some additional constraints, all orbits become periodic, most of them Lyapounov stable, and with a maximal period in any bounded domain of phase space. This yields a class of maps acting on a discrete phase space. 相似文献
168.
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170.