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71.
At a pressure of 10?6 Torr the ion cyclotron resonance spectra of p-benzoquinone, methyl-p-benzoquinone, tetramethyl-p-benzoquinone and tetrafluoro-p-benzoquinone are identical to the normal mass spectra. Above 10?5 Torr the spectra show a variety of signals for product ions. From double resonance measurements it was shown that all the product ions are formed by addition of the molecular ion or of a fragment ion to a neutral quinone molecule. In most cases the addition is accompanied by the elimination of carbon monoxide. 相似文献
72.
Harald Löwe 《Geometriae Dedicata》1995,58(1):45-51
We construct symmetric planes associated with an arbitrary locally compact connected nearfield
. If
is a proper nearfield, i.e.
{;;}, then the tangent translation plane of this symmetric plane is not classical. All previously known examples of symmetric planes have classical tangent translation planes.Herrn Professor Dr. H. Salzmann zum 65. Geburtstag gewidmet 相似文献
73.
Consider the variational integral
where Ω⊂ℝ
n
andp≥n≥2. H: (0, ∞)→[0, ∞) is a smooth convex function such that
. We approximateJ by a sequence of regularized functionalsJ
δ whose minimizers converge strongly to anJ-minimizing function and prove partial regularity results forJ
δ-minimizers. 相似文献
74.
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P. Ackerbauer W. H. Breunlich M. Fuchs S. Fussy M. Jeitler P. Kammel B. Lauss J. Marton W. Prymas J. Werner J. Zmeskal K. Lou C. Petitjean P. Baumann H. Daniel F. J. Hartmann W. Schott T. von Egidy P. Wojciechowski D. Chatellard J. P. Egger E. Jeannet T. Case K. M. Crowe R. H. Sherman V. Markushin 《Hyperfine Interactions》1993,82(1-4):243-258
Complementary to the investigations of the most efficient dt cycle, also the other muon-induced fusion cycles in mixtures of hydrogen isotopes have been studied. The results of these dedicated experiments provide rich information about muon-induced few-body reactions and contribute significantly to a better overall understanding of CF. A summary of the recent progress will be presented. Special emphasis will be put on two characteristic examples, namely a new experimental approach to study the muonic cascade in H-D mixtures and the systematic study of hyperfine effects in muon-induced reactions. 相似文献
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Vaporization of Silver in a Stream of Oxygen Using a transport equipment the vaporization of silver at 611–721°C in a stream of oxygen has been measured. Experiments with detachable cuffs of silver or with wools of silver in a bulb made from quartzglass or silver lead to the same results. By variation of the O2-pressure and the activity of silver is observed that the vaporization happens as Ag2O,g, see “Inhaltsübersicht”. The solid was at first pure silver. During long lasting experiments, however, it is covered with a thin layer of oxygen or silver oxide, which lowers the concentration of Ag2O,g in the equilibrium gas to a smaller, yet constant value. The following measurements using N2 as carrier gas lead to the decomposition of this layer and ends with the very small vapor pressure of silver. The layer of oxygen or silver oxide on the metal could be shown after Davies [2] using mercury. 相似文献