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31.
Novel oxyfluoride and fluoride sulfide anions are generated by the isoelectronic replacement of F in a main-group polyfluoride by O- or S- via the reaction of either tBuO- or RS- (R: H, Me) with the polyfluorides. 相似文献
32.
is determined by electron diffraction at 195-220 °C. The diffraction patterns are completely consistent with a molecule of tetrahedral (Td) symmetry. 相似文献
33.
34.
Ernst S. Selmer 《BIT Numerical Mathematics》1989,29(1):37-40
A boundO(N
1+1/k
) for the running time of Shellsort, withO(logN) passes, is proved very simply by application of a Frobenius basis withk elements. 相似文献
35.
36.
T. Salditt H. Rhan T. H. Metzger J. Peisl R. Schuster J. P. Kotthaus 《Zeitschrift für Physik B Condensed Matter》1994,96(2):227-230
We measure the nonspecular x-ray scattering at grazing incidence and exit angles from a GaAs surface, modulated by an one-dimensional lateral grating of effectively variable periodicity 1 md60 m. Due to the projection onto the sample surface, the lateral coherence length is enlarged by a factor of more than 100. The line broadening of the diffraction maxima is used to deduce the number of periods that add up coherently for a given periodd and given angle of incidence. We demonstrate that the scattering geometry used allows for large coherently illuminated lengths on the sample and ultra small angle resolution of one- or two-dimensional objects. Thus structures of m size and larger will be accessible by coherent x-ray scattering. 相似文献
37.
G. Grawert 《Zeitschrift für Physik A Hadrons and Nuclei》1994,348(4):293-300
Experimental results of the 1st rank analyzing power for elastic scattering of6Li and7Li could be only understood when including coupling to inelastic channels in the calculations. This finding — established for some time — yet presents some open questions regarding the energy dependence of the spin and polarization effects. Semiclassical calculations presented here might clarify the relevant physical background of the earlier quantummechanically exact results. 相似文献
38.
We study linearly ordered spaces which are Valdivia compact in their order topology. We find an internal characterization of these spaces and we present a counter-example disproving a conjecture posed earlier by the first author. The conjecture asserted that a compact line is Valdivia compact if its weight does not exceed ℵ1, every point of uncountable character is isolated from one side and every closed first countable subspace is metrizable. It turns out that the last condition is not sufficient. On the other hand, we show that the conjecture is valid if the closure of the set of points of uncountable character is scattered. This improves an earlier result of the first author. 相似文献
39.
It is shown that every continuous action of a solvable group on a 1-arcwise connected continuum must have a fixed point or have a 2-periodic point. 相似文献
40.
Hanspeter Schmidli 《Insurance: Mathematics and Economics》2010,46(1):3-11
We consider several models for the surplus of an insurance company mainly under some light-tail assumptions. We are interested in the expected discounted penalty at ruin. By a change of measure we remove the discounting, which simplifies the expression. This leads to (defective) renewal equations as they had been found by different methods in the literature. If we use the change of measure such that ruin becomes certain, the renewal equations simplify to ordinary renewal equations. This helps to discuss the asymptotics as the initial capital goes to infinity. For phase-type claim sizes, explicit formulae can be derived. 相似文献