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911.
An X-ray photoelectron spectroscopy (XPS) study was undertaken of the water/Cu(1 1 0)-system finding non-dissociative adsorption on clean Cu(1 1 0) at temperatures below 150 K. Thermally induced dissociation of D2O is observed to occur above 150 K, similar to the H2O/Ru(0 0 1) system, with an experimentally derived activation barrier of 0.53-0.56 eV which is very close in magnitude to the derived activation barrier for desorption of 0.50-0.53 eV. X-ray and electron induced damage to the water overlayer was quantified and used to rationalize the results of a recent XPS study of the water/Cu(1 1 0)-system where partial dissociation was observed already at 90 K.  相似文献   
912.
This Note is devoted to the study of a fluid–rigid body interaction problem. The motion of the fluid is modelled by the Navier–Stokes equations, written in an unknown bounded domain depending on the displacement of the rigid body. Our main result yields the existence and uniqueness of strong solutions, which are global provided that the rigid body does not touch the boundary. To cite this article: T. Takahashi, C. R. Acad. Sci. Paris, Ser. I 336 (2003).  相似文献   
913.
The Sb-121 Mössbauer parameters at 20 K for 23 antimony(III) compounds were obtained and the data are discussed in terms of known crystal structures. The isomer shifts and quadrupole coupling constants depend strongly on the type of configuration around the Sb(III) atoms with stereochemically active lone pair electrons.  相似文献   
914.
In this paper, from an arbitrary smooth projective curve of genus at least two, we construct a non-Gorenstein Cohen-Macaulay normal domain and a nonfree totally reflexive module over it. Received: 2 May 2006  相似文献   
915.
We conducted laser vaporization of graphite and graphite containing 1 at. % silicon in Ar gas atmosphere. Comparison of the products from the laser vaporization indicated that the coexistence of Si promoted graphitization in grown carbon particles of 90–1500 nm. Polyhedral graphite (PG) particles and balloon-like carbon (BC) particles with shells of graphitic layers were grown under control of Ar gas pressures of 0.1–0.7 MPa. We discuss possible roles of Si in graphitic structure growth and the formation mechanisms of the PG and BC particles. PACS 81.16.Mk; 61.46.Df; 68.37.Lp  相似文献   
916.
917.
The conjugative interaction between the two terminal groups in title quinarenone 2 and its chloro- and methoxy-derivatives were evaluated, proving that the diatropicity of the seven-membered ring is a little larger in 2 than in tropone. Some of these quinarenones are also found to exist in equilibrium with their oligomers and show unexpectedly low barriers of rotation about the intercyclic bond.  相似文献   
918.
We report the development of a fast pulse polarimeter for the application to quantum non-demolition measurement of atomic spin (spin QND). The developed system was tunable to the atomic resonance of a ytterbium atom and has narrow laser line width suitable for spin QND. Using the developed polarimeter, we successfully demonstrated the measurement of the vacuum noise, with 106 to 107 photon number per pulse. PACS 42.25.Ja; 42.50.Lc; 42.55.Px  相似文献   
919.
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   
920.
An improved and efficient synthesis of 1,3-dialkylpyrido[2,3-d]pyrimidine-2,4-(1H,3H)-diones from 6-methylaminouracils and methyl propiolate or diethyl ethoxymethylenemalonate is described.  相似文献   
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