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131.
132.
The role of material microstructure in the magnetic anisotropy of real nanostructures has been studied by the comparison of the magnetic behavior of arrays of amorphous and polycrystalline CoxSi1-x lines. From the experimental measurements of angular dependences of remanences parallel and perpendicular to the applied field we determine the angular dispersion of effective local easy axis of anisotropy. We have proved that amorphous lines have a dispersion of effective anisotropy axis much smaller than the polycrystalline samples. As a consequence, amorphous lines have a better defined magnetic behaviour, pointing the interest of the fabrication of nanostructures made of amorphous materials.  相似文献   
133.

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   
134.
Single pi(0) photoproduction has been studied with the CB-ELSA experiment at Bonn using tagged photon energies between 0.3 and 3.0 GeV. The experimental setup covers a very large solid angle of approximately 98% of 4pi. Differential cross sections dsigma/dOmega have been measured. Complicated structures in the angular distributions indicate a variety of different resonances being produced in the s channel intermediate state gammap-->N(*)(Delta(*))-->ppi(0). A combined analysis including the data presented in this letter along with other data sets reveals contributions from known resonances and evidence for a new resonance N(2070)D15.  相似文献   
135.
Locally periodic Timoshenko rod: experiment and theory   总被引:2,自引:0,他引:2  
The flexural vibrations of a locally periodic rod, which consists of N unit cells, are discussed both from the experimental and theoretical points of view. Timoshenko's beam theory and the transfer matrix method are used to calculate the normal-mode frequencies and amplitudes. The theoretical values are then compared with the experimental ones, which are obtained using an electromagnetic acoustic transducer (EMAT). Good agreement between the numerical results and the experimental measurements is obtained. It is shown that as N grows, a band spectrum emerges.  相似文献   
136.
A method for the synthesis of diphenylacetylenes containing donor and acceptor groups in aryl substituents was proposed. 4"-Formyl-4-methoxydiphenylacetylene was synthesized as an example.  相似文献   
137.
A particle-in-cell code is used to investigate the evolution of a density plume moving through a background plasma with supersonic speed directed along the confinement magnetic field. For scale lengths representative of laboratory and auroral phenomena, the major nonlinear effects identified by the present simulations are the formation of a bipolar current system from the ballistic electrons, the appearance of transient potential layers, and the carving of deep density cavities. A 3D magnetic topology is generated by the self-consistent ballistic and diamagnetic currents that accompany highly localized potential layers.  相似文献   
138.
The carboxylic acid-pyridine supramolecular heterosynthon can be exploited to predictably generate binary crystalline phases involving rac-ibuprofen, rac-flurbiprofen or aspirin.  相似文献   
139.
Let be an Axiom A flow with a transverse torus exhibiting a unique orbit that does not intersect . Suppose that there is no null-homotopic closed curve in contained in either the stable or unstable set of . Then we show that has either an attracting periodic orbit or a repelling periodic orbit or is transitive. In particular, an Anosov flow with a transverse torus is transitive if it has a unique periodic orbit that does not intersect the torus.

  相似文献   

140.
Morales  P.  Mazarío  F. García  Guerra  P. Jiménez 《Order》2000,17(1):43-60
Let (X, F) be an Alexandroff space, let A(F) be the Boolean subalgebra of 2 X generated by F, let G be a Hausdorff commutative topological lattice group and let rbaF(A(F), G) denote the set of all order bounded F-inner regular finitely additive set functions from A(F) into G. Using some special properties of the elements of rbaF(A(F), G), we extend to this setting the first decomposition theorem of Alexandroff.  相似文献   
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