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821.
822.
J. -M. R. Génin A. A. Olowe B. Resiak M. Confente N. Rollet-Benbouzid S. L'Haridon D. Prieur 《Hyperfine Interactions》1994,93(1):1807-1812
An unusual low-water corrosion of steel sheet piles has been systematically investigated in a channel harbour (Boulogne sur Mer, France). An analysis of the environment reveals that all sampling of dark rust taken at different heights above marine sediments and kept in anaerobic conditions present unusual concentrations of sulfate-reducing bacteria. The rust products have been characterized by Mössbauer spectroscopy and X-ray diffraction, comprising the ferrous—ferric sulfated compounds of formula 4Fe(OH)2 · 2FeOOH · FeSO4 ·nH2O, called green rust 2, mixed sometimes with magnetite and a small amount of ferrous sulfide. 相似文献
823.
P. Prené E. Tronc J. P. Jolivet J. Livage R. Cherkaoui M. Noguès J. L. Dormann 《Hyperfine Interactions》1994,93(1):1409-1414
Investigation by Mössbauer spectroscopy of non-aggregated nanometric -Fe2O3 particles dispersed in polymer is reported. Magnetic interactions between the particles were controlled by varying the particle concentration in the polymer. The results show that over the investigated range, the interactions make the relaxation time shorter. Infield experiments show spin canting which increases with decreasing particle size. 相似文献
824.
825.
S. Perries A. Astier L. Ducroux R. Duffait Y. Le Coz M. Meyer N. Redon F. Azaiez S. Bouneau C. Bourgeois R. Collatz I. Deloncle B. J. P. Gall F. Hannachi I. Hibbert A. Korichi A. Lopez-Martens R. Lucas V. Méot N. Poffé M. G. Porquet C. Schück H. Sergolle J. F. Sharpey-Schafer R. Wadsworth A. N. Wilson 《Zeitschrift für Physik A Hadrons and Nuclei》1996,354(1):1-2
The francium isotopes200–202Fr were produced in the reaction35Cl+170Yb using bombarding energies of 4.9–5.3 MeV/nucleon. Fusion products were separated in-flight from the primary beam using
a gas-filled recoil separator. An alpha line with the alpha particle energy and half-life of (7468±9) keV and (19
−6
+13
) ms, respectively, was assigned to200Fr. Previously reported decay properties of201,202Fr were confirmed.
Communicated by V. Metag 相似文献
826.
J. P. Fillard M. Castagné M. Benfedda S. Lahimer H. U. Danzebrink 《Applied Physics A: Materials Science & Processing》1996,63(5):421-425
Silicon AFM tips can profitably be used as optical sensors for near field optical microscopy. In particular they are able to convert evanescent waves (also called virtual photons) into propagating ones which are conveniently guided in the tip and transferred to the air at the back of the cantilever. In this paper it is shown that virtual photons scattered at the tip end are also converted into real ones which are observed in the far field. Contrary to the previous observations of similar conversion at STM metal tips the scattered emission at dielectric silicon tips does not have a dependence with distance of a full exponential decay but rather follows the more complex dependence of the dielectric capture. This observation is consistent with Mie's theory of scattering of real photons by small particles. Experiments are performed with boths andp polarizations showing a regular dependence of the scattered intensity with the incidence angle. The same experiment is also performed with metallized silicon tips showing a metal scattering behaviour. This results can help to achieve a better control of the tip position in the close range of distances in a Photon Scanning Tunneling Microscopy (PSTM) experiment. 相似文献
827.
R. S. Dunne A. J. Macfarlane J. A. de Azcárraga J. C. Pérez Bueno 《Czechoslovak Journal of Physics》1996,46(12):1235-1242
Theq-calculus for genericq is developed and related to the deformed oscillator of parameterq
1/2. By passing with care to the limit in whichq is a root of unity, one uncovers the full algebraic structure ofZ
n
-graded fractional supersymmetry and its natural representation.Presented at the 5th International Colloquium on Quantum Groups: Quantum Groups and Integrable Systems, Prague, 20–22 June 1996.This paper describes research supported in part by E.P.S.R.C and P.P.A.R.C. (UK) and by the C.I.C.Y.T (Spain). J.C.P.B. wishes to acknowledge an FPI grant from the CSIC and the Spanish Ministry of Education and Science. 相似文献
828.
We apply the pseudoextension mechanism, which in the undeformed case gives the centrally extended Galilei group {ie137-02} as a contraction of a trivial extensionP×U(1) of the Poincaré group, to the case of the-Poincaré algebra. As a result, the four-dimensional {ie137-03}-deformed extended Galilei algebra is obtained.Presented at the 4th Colloquium Quantum Groups and Integrable Systems, Prague, 22–24 June 1995. 相似文献
829.
830.