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921.
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   
922.
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   
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924.
Dielectric and infrared data have been obtained over a wide temperature range on copolymers of ethyl methacrylate with methacrylic and acrylic acid synthesized by radical copolymerization. The dissociation energy ΔH0 for the acid dimer in the copolymer is estimated from the temperature dependence of the relaxation strength Δεα of the α relaxation, which is associated with the glass transition. The value of δH0 obtained by this method is in fair agreement with that determined by infrared (IR) spectroscopy. The strength of the α relaxation and its activation energy are both increased by the incorporation of methacrylic acid units but are decreased by acrylic acid units. This behavior is attributed to the restriction of main-chain motions by hydrogen-bonded acid dimers in the copolymers with methacrylic acid and to the incorporation of more flexible links in the copolymers with acrylic acid. The β relaxation observed below the glass transition temperatures is almost unaffected by the incorporation of methacrylic acid.  相似文献   
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926.
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   
927.
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   
928.
We show that there exist only finitely many imaginary abelian number fields of type (2,2,...,2) with one class in each genus. Moreover, if the Generalized Riemann Hypothesis is true, we have exactly 301 such fields, whose degrees are less than or equal to 23. Finally we give the table of those 301 fields.  相似文献   
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