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61.
J. Bartke M. Deutschmann H.G. Kirk P. Sixel L. Becker H. Vogt R. Hartmann H. Plothow D. Kocher D.R.O. Morrison P. Porth K. Eskreys K. Olkiewicz K. Doroba T. Hofmokl 《Nuclear Physics B》1977,120(1):1-13
Interactions in which the baryon is emitted forwards in the c.m.s. are studied in 8 and 16 GeV/cπ+p collisions. These interactions are interpreted as representing baryon exchange. The properties of such off-shell N annihilation events are studied. It is found that the multiplicity distribution of the multi-pion system as a function of the effective mass for events with |upp| < 1 GeV2 is the same as for real annihilations. 相似文献
62.
Dietmar Vogt 《Mathematische Annalen》1972,196(4):281-292
Ohne Zusammenfassung 相似文献
63.
The optical properties of uranium sulphide single crystals have been determined for the first time. An excellent agreement is found between the structure in the optical spectrum and the results of a self-consistent cellular multiple scattering calculation. The results evidence that the 5? electrons form a resonance state at EF and that the 5??6d coupling produces a dip in the 6d density of states near EF which is responsible for many peculiar properties of US. 相似文献
64.
Changes in the magnetic field-temperature phase diagram of CeSb with pressure have been determined up to 6kbar by magnetization measurements on a single crystal. High magnetic fields up to 70 kOe have been applied along a four fold axis of the rock-salt type structure. The features of the phase diagram are not changed by pressure except for a shift towards high temperature. The saturated magnetic moment and the hysteresis of the transition fields are independent of pressure. Variation of exchange energy with volume is deduced from the experimental results. It is shown that the effect of pressure and the magnetic volume anomaly at 0 K are essentially due to the variation of the exchange energy in the ferromagnetic (001) planes. 相似文献
65.
Dr. Pierre Junod Dr. A. Menth Dr. O. Vogt 《Zeitschrift für Physik B Condensed Matter》1969,8(5):323-370
This report reviews the most important publications, as well as many unpublished measurements by the authors. The influence of the cubic crystal field on the magnetic properties of binary compounds containing the trivalent Ions Pr3+, Sm3+, Tm3+ and Yb3+ is studied. Crystalfield- and exchange parameters (molecularfield approximation) were determined for the ferromagnetic nitrides GdN, TbN, DyN, HoN and ErN. The mechanism of the electrical conductivity is still unknown. 相似文献
66.
G. Ransoné P. Sixel H.H. Kaufmann R. Klein H. Vogt H. Dreverman D. Kuhn J.P. Porte R.T. Ross F. Triantis K. Dziunikowska B. Muryn K.W.J. Barnham J. Wells P.R.S. Wright D. Dallman F. Mandl M. Szczekowski 《Nuclear Physics B》1980,167(3):285-291
The charged multiplicity distribution is presented for K?p interactions produced in the hydrogen bubble chamber, BEBC, using an r.f. separated, tagged K? beam of 110 GeV/c momentum. A comparison with K+p, πp and pp data at lower energies shows that the main features of the multiplicity distributions depend on energy and charge of the incident particles, but not on their strangeness. At high energies, only the energy is important. 相似文献
67.
The photochemical dimerization of 2-2-benzazepine-1,3-diones has been described. The structures of the major products are assigned as the head-to-tail, 5, and the head-to-head. 7, photodimers on the basis of the analysis of the coupling constants in the NMR spectra. In addition, the structures of the minor products and attempts to convert 5 to 7 are discussed. 相似文献
68.
Investigations on the energy dependence of the cross section of charge transfer reactions with negative ions yield evidence on the relative values of the electron affinities of the colliding particles. It is shown that H?+ O2 and SO? + O2 are exothermic and that ND 2 ? + O2 is anendothermic reaction. With EA(H)=0.776eV, EA(SO)=1.05eV and EA (ND2) ≈ 1.2 eV we find 1.05 eV < EA (O2) < ≈ 1.2 eV. 相似文献
69.
Vogt U Lindblom M Jansson PA Tuohimaa TT Holmberg A Hertz HM Wieland M Wilhein T 《Optics letters》2005,30(16):2167-2169
We report on a compact interferometer for the water-window soft-x-ray range that is suitable for operation with laser-plasma sources. The interferometer consists of a single diffractive optical element that focuses impinging x rays to two focal spots. The light from these two secondary sources forms the interference pattern. The interferometer was operated with a liquid-nitrogen jet laser-plasma source at lambda=2.88 nm. Scalar wave-field propagation was used to simulate the interference pattern, showing good correspondence between theoretical and experimental results. The diffractive optical element can simultaneously be used as an imaging optic, and we demonstrate soft-x-ray microscopy with interferometric contrast enhancement of a phase object. 相似文献
70.
Five-coordinate phenylsilicates are formed from the reaction of trimethoxy(phenyl)silane with monosaccharides in methanol in the presence of a stoichiometric amount of base. Five complexes have been isolated and characterized with two ketoses and three aldopentoses. The silicon central atom in [K([18]crown-6)][PhSi(beta-D-Fruf 2,3H-2)2].MeOH (1, Fru=fructose) is part of two chelate rings, with the ligands being beta-D-fructofuranose-O2,O3 dianions. The beta-furanose isomer is best suited for silicon ligation because it exhibits a torsion angle close to 0 degrees for the most acidic diol function, thus assuring a flat chelate ring. The same structural principles are also found in [K([18]crown-6)][PhSi(beta-D-Araf1,2H-2)2].2 MeOH (2, Ara=arabinose), [K([18]crown-6)][PhSi(alpha-D-Ribf1,2H-2)2] (3, Rib=ribose), [K([18]crown-6)][PhSi(alpha-D-Xylf1,2H-2)2]. acetone (4, Xyl=xylose), and [K([18]crown-6)][PhSi(alpha-D-Rulf2,3H-2)2] (5, Rul=ribulose). 相似文献