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91.
92.
Ch. Ohn 《Letters in Mathematical Physics》1992,25(2):85-88
We obtain Zakrzewski's deformation of Fun SL(2) through the construction of a *-product on SL(2). We then give the deformation of
dual to this, as well as a Poincaré basis for both algebras.Aspirant au Fonds National belge de la Recherche Scientifique. Partially supported by EEC contract SC1-0105-C. 相似文献
93.
94.
Fulton R Jensen T Johnson DR Kagan H Kass R Morrow F Whitmore J Wilson P Bortoletto D Chen W Dominick J McIlwain RL Miller DH Ng CR Schaffner SF Shibata EI Shipsey IP Yao W Battle M Sparks K Thorndike EH Wang C Alam MS Kim IJ Li WC Romero V Sun CR Wang P Zoeller MM Goldberg M Haupt T Horwitz N Jain V Mestayer MD Moneti GC Rozen Y Rubin P Sharma V Skwarnicki T Thulasidas M Zhu G Csorna SE Letson T Alexander J Artuso M Bebek C Berkelman K Browder T Cassel DG Cheu E Coffman DM Crawford G DeWire JW 《Physical review D: Particles and fields》1991,43(3):651-663
95.
96.
Straub PB Jaffe DE Glass HD Adams MR Brown CN Charpak G Cooper WE Crittenden JA Finley DA Gray R Hemmi Y Hsiung YB Hubbard JR Jonckheere AM Jöstlein H Kaplan DM Lederman LM Luk KB Maki A Mangeot P McCarthy RL Miyake K Plaag RE Rutherfoord JP Sakai Y Santiard JC Sauli F Smith SR Yoshida T Young KK 《Physical review letters》1992,68(4):452-455
97.
M. Bourquin R. M. Brown Y. Chatelus J. C. Chollet A. Degré D. Froidevaux A. R. Fyfe J. -M. Gaillard C. N. P. Gee W. M. Gibson R. J. Gray P. Igo-Kemenes P. W. Jeffreys B. Merkel R. Morand R. J. Ott H. Plothow J. -P. Repellin B. J. Saunders G. Sauvage B. Schiby H. W. Siebert V. J. Smith K. -P. Streit R. Strub J. J. Thresher 《Zeitschrift fur Physik C Particles and Fields》1982,12(4):307-321
The charged hyperon beam at the CERN Super Proton Synchrotron (SPS) has been used to collect data on semileptonic decays ofΣ ?,Ξ ? andΛ. A magnetic channel selects 100 GeV/c negatively charged particles produced in the forward direction by interaction of the 200 GeV/c SPS proton beam on a BeO target. TheΣ ? andΞ ? hyperons are concurrently identified in a DISC ?erenkov counter, and their decay products are analysed by a magnetic spectrometer. Electron-hadron discrimination is achieved by the combined use of lead-glass and lead/scintillator counters, transition radiation detectors, and a ?erenkov counter. In this article we report results on the \(\Sigma ^ - \to \Lambda e^ - \bar v\) decay mode. Measurements of the Λ polarization and of the centre-of-mass distributions (baryon kinetic energy, electron-neutrino correlation, and Dalitz plot distributions) yield the vector to axialvector form factor ratiof 1/g 1=+0.034±0.080, in agreement with the value expected from the conserved vector current hypothesis (f 1/g 1=0). TheΣ ?→Λe ? v→ branching ratio measurement gives a value of (5.41±0.30)×10?5. The effects of radiative corrections are not included in these results. They are discussed in the text. Results on the otherΞ ?,Σ ?, andΛ semileptonic decays are reported in separate articles. 相似文献
98.
Catalytic gas-phase abatement of air containing 250 ppm of isopropanol (IPA) was carried out with a novel dielectric barrier
discharge (DBD) reactor with the inner catalytic electrode made of sintered metal fibers (SMF). The optimization of the reactor
performance was carried out by varying the voltage from 12.5 to 22.5 kV and the frequency in the range 200–275 Hz. The performance
was significantly improved by modifying SMF with Mn and Co oxide. Under the experimental conditions used, the MnO
x
/SMF showed a higher activity towards total oxidation of IPA as compared to CoO
x
/SMF and SMF electrodes. The complete destruction of 250 ppm of IPA was attained with a specific input energy of ∼235 J/L
using the MnO
x
/SMF catalytic electrode, whereas, the total oxidation was achieved at 760 J/L. The better performance of the MnO
x
/SMF compared to other catalytic electrodes suggests the formation of short-lived active species on its surface by the in-situ
decomposition of ozone. 相似文献
99.
Thermodynamic and kinetic parameters have been determined suitable for the numerical simulation of the curing reaction of the epoxy/anhydride based casting resin system Araldite CY 225/HY 225/filler. In particular, the decisive role of the heating rate on the evaluation of the kinetic parameters from dynamic DSC-experiments is discussed.
We wish to thank Dr. P. Bujard, Ciba-Geigy SA, for the measurement of the thermal conductivity data, and Mrs. Emmi Stoisser for technical assistance. 相似文献
Zusammenfassung Mit Hilfe der Mikrokalorimetrie wurden thermodynamische (Reaktionsenthalpien) und kinetische (Arrhenius-Konstanten, Reaktionsordnung) Parameter eines gefüllten Epoxid/Anhydrid-Giessharz-Systems (Araldit CY 225/HY 225/Quarzmehl) bestimmt.Die Eignung dieser Parameter zur praxisrelevanten Simulation der HÄrtungsreaktion in Giessformen wird demonstriert. Es zeigt sich, dass die Heizrate im dynamischen DSC-Experiment bei der Bestimmung der kinetischen Parameter eine entscheidende Rolle spielt.
We wish to thank Dr. P. Bujard, Ciba-Geigy SA, for the measurement of the thermal conductivity data, and Mrs. Emmi Stoisser for technical assistance. 相似文献
100.
F. Vogt H. Bremer F. Hofmann Ja. I. Isakov Ch. M. Minaßev T. A. Isakova 《无机化学与普通化学杂志》1985,521(2):145-152
Studies on Oxide Catalysts. XLii. Redox Behaviour of Nickel in Zeolites NiNa? Y. 4. Influence of Composition on the Reducibility of Nickel in Zeolites NiNa? Y By chemical analysis (reaction with K2Cr2O7) and ESCA investigations we determined the degree of reduction in reduced samples NiNa-Y as function of the mole ratio SiO2/Al2O3 (module), of the Ni2+ degree of exchange and the kind of the second cations. (NH4+, Ca2+, Co2+, and Nd3+) in the temperature region of 620–770 K. The degree of nickel reduction increases with increasing module, decreasing degree of exchange and decreasing number of Brönsted acidic centres. This behaviour is caused by the influence of the interaction between cations Ni2+ and zeolite lattice on the reduction equilibrium. 相似文献