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Using the method of atomic-beam magnetic resonance, detected by laser-induced resonance fluorescence (ABMR-LIRF), the atomic ground-state hyperfine intervals of 50V were precisely measured. A quadrupole moment ratio Q(50V) / (51V = ?4.03(3) is obtained which results in Q(50V) = +0.21(4) b.  相似文献   
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Summary Let (X, A, P) be a measure space with P(X)=1 and a sub--algebra. It is well known (see e.g. Doob, p. 624) that even if A is separable, a regular conditional probability (r.c.p.) on A, given , does not always exist. All theorems assuring the existence of a r.c.p. known hitherto use in addition to the separability of A conditions of an essentially topological nature such as compact approximation (for references see e.g. Pfanzagl-Pierlo (1966), section 7).It is the purpose of this paper to explore the possibility of sufficient conditions of a purely measure-theoretic nature. Without loss of generality we may assume that (X, A, P) is complete and is complete with respect to P ¦A. For many applications it will be sufficient to have the r.c.p. defined on a sub--algebra A 0 A with A 0 ~ A(P|A) rather than on the whole -algebra A. It will be shown that a r.c.p. in this more restricted sense always exists if A is the completion of a separable -algebra and if it contains a P-null set of the power of the continuum. The P-null-set -condition cannot be omitted without any replacements. To be more specific: Even a r.c.p. in the restricted sense does not necessarily exist if A is the completion of a separable -algebra (see Example 1). Furthermore, there are instances, in which a r.c.p. in the restricted sense exists but a r.c.p. in the usual sense does not exist (see Example 2).Even if a r.c.p. exists, it is not necessarily proper. The deep study by Blackwell and Ryll-Nardzewski (1963) reveals that this negative statement even holds under rather restrictive conditions (X = complete separable metric space, A = Borel algebra of X). It therefore seems to be of some interest to state that the r.c.p. in the restricted sense can always be chosen such that it is proper with respect to some sub--algebra +Bo +(+B A 0 with 00(P¦A).  相似文献   
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This paper realizes an idea ofRedfield in a general and quantitative manner: Charged point defects produce local electric fields in a crystal which cause a change in the absorption-constant compared with the absorption-constant of an undisturbed crystal (Franz-Keldysh-effect). Thus one gets a tail in the absorption constant decreasing from the ideal intrinsic absorption edge towards longer wave-lengths. Applying an external fieldF one finds an additional, frequency-dependent absorptionconstantΔα. Its magnitude and spectral distribution depend on the concentration of defects. For external fields smaller than the internal onesΔα∝ F 2 holds at all frequencies. The results are compared with those found byFranz.  相似文献   
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The synthesis of five eight-electron-ligands, two six-electron-ligands and one four-electron-ligand for transition metals is described. These heterocycles contain in each case arsenic and sulfur as heteroatoms, and additionally oxygen in one case.  相似文献   
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