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821.
A single-electron circuit can be operated as a discrete dynamical system because it changes its internal state discontinuously because of electron tunneling. To confirm this idea, we designed a sample circuit for discrete dynamical operation and confirmed by computer simulation that the circuit successfully generated a sequence of discrete-time outputs by following a return map. The concept of discrete dynamical systems will be useful in developing new functional systems that consist of quantum devices and nanostructures.  相似文献   
822.
Nomura  K.  Takahashi  K.  Takeda  M.  Shimizu  K.  Habasaki  H.  Kuzmann  E. 《Hyperfine Interactions》2004,156(1-4):629-636
Hyperfine Interactions - Thin stainless steel films were deposited on surface oxidized Si plate using austenitic AISI304 stainless steel as target with a RF magnetron Ar sputtering method. The...  相似文献   
823.
We have developed an (e,2e) spectrometer with the introduction of modern multiparameter techniques. In particular, the high sensitivity achieved by simultaneous detection in energy and momentum is remarkable, opening up the possibilities of more precise and more advanced studies on the electronic structure of atoms and molecules. To illustrate some of the features, an overview of our recent results is presented. Highlights are applications to collision dynamics of H2 and development of a method for a complete three-dimensional mapping of electron momentum densities in gaseous molecules. Both of these studies are based on the high sensitivity of the spectrometer.  相似文献   
824.
825.
826.
This paper develops a new representation theory of multivariabletime-invariant linear systems based on the well-known coprimefactorizations of their transfer matrices. This representationfully uses the algebraic structure of coprime factorizations,and hence has a number of advantages for describing variousproperties of linear systems in simpler and/or more compactforms than the usual transfer matrix representation. In theframework of this new representation theory, various stabilityand stabilizability properties of linear systems are characterizedand finally a simultaneous stabilization problem for a givenset of linear systems is examined.  相似文献   
827.
Films of Bi2O3 were grown on glass substrate under atmospheric pressure by means of halide chemical vapour deposition (AP-HCVD) using BiI3 and O2 as the starting materials. In the XRD diffractogram of the film a strong diffraction peak appears at 27.91° assigned to the (111) diffraction of the δ-Bi2O3 with cubic structure. X-ray pole figure suggested that the 〈111〉 direction of the film is perpendicular to the substrate surface, while the 〈110〉 axis directs towards all directions parallel to the substrate surface. It is for the first that δ-Bi2O3 film was prepared on glass substrate.  相似文献   
828.
829.
A systematic study of organoantimony(III) compounds, SbR3, was attempted in view of the effect on Mössbauer parameters of the substituent on the aromatic ring. The Mössbauer parameters obtained in frozen organic solutions reflected the electronic effect caused by the characteristics of the substituents, electron donative or attractive, at the para position on the aromatic ring.  相似文献   
830.
Ejectile nuclei in the fragmentation of intermediate-energy heavy-ion projectiles were found to be largely spin polarized. The observed polarization as a function of the outgoing momentum was nicely explained by a simple kinematical argument based on the participant-spectator model of projectile fragmentation. The measurements extended to cover several different targets, incident energies, exit channels, and emission angles revealed that substantial polarization shows up widely in projectile fragmentation reactions. Furthermore, this polarization exhibits an interesting behavior which may be interpreted as a manifestation of a gradual change in the deflection angle from positive to negative values as the energy increases and/or the target-Z decreases. The present polarization results also suggests various applications of spin polarized radioactive beams. As the first example of such an application, we present a recent result on theg-factor measurements on neutron-rich nuclei.  相似文献   
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