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31.
We introduce a quite natural Frege‐style set theory, which we call Strong‐Frege‐2 $(\mathsf {SF}_2)$, a sort of simplification of the theory considered in 13 (under the name Strong‐Frege‐3) and 1 (under the name F2). We give a model of a weaker variant of $\mathsf {SF}_2$, called $\mathsf {SF}_2\mathsf {AC}$, where atoms and coatoms are allowed. To construct the model we use an enumeration “almost without repetitions” of the Π11 sets of natural numbers; such an enumeration can be obtained via a classical priority argument much in the style of 5 and 15 . © 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim  相似文献   
32.
The electrical response of an electrolytic cell in which the diffusion of mobile ions in the bulk is governed by a fractional diffusion equation of distributed order is analyzed. The boundary conditions at the electrodes limiting the sample are described by an integro-differential equation governing the kinetic at the interface. The analysis is carried out by supposing that the positive and negative ions have the same mobility and that the electric potential profile across the sample satisfies the Poisson's equation. The results cover a rich variety of scenarios, including the ones connected to anomalous diffusion.  相似文献   
33.
The structure of 105Sn has been investigated through the 50Cr(58Ni,2pn) reaction at a beam energy of 210 MeV. In addition to an extension of the spherical level scheme, a regular sequence of dipole transitions has been found. The experimental results are in agreement with the prediction of Tilted Axis Cranking calculations, which satisfactorily explain the properties of the band.  相似文献   
34.
We study pairing correlations in deformed nuclei in the framework of the Nilsson+BCS theory. As in the spherical case, the pairing interaction is found to induce strong spacial correlations between the partners of each paired couple. The presence of the deformed mean field gives rise to a non-spherical pair field, whose deformation is governed by the properties of a few single-particle orbitals around the Fermi surface and does not necessarily follow the shape of the mean field. Multipole expansion of the pair field yields all the pair densities associated with the direct two-particle transfer processes to the members of the g.s. rotational band in the A+2 system. The interplay of the deformations of the mean and the pair fields can lead to different relative magnitudes and phases of these densities and therefore to different excitation patterns of the rotational bands in two-particle transfer reactions. In the case of non-collective twoquasiparticles and bands the associated pair densities display large components with high multipoles and the associated transfer processes may be favoured in heavy-ion collisions by kinematical conditions. Examples corresponding to both prolate and oblate cases are considered.  相似文献   
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The apparent molal volume v of sucrose in water has been measured at 25°C in the concentration range 0.04–4.4m from precise density measurements. The same property was also determined for dilute solutions of sucrose in mixed aqueous solvents containing NaCl, KCl, or urea. The limiting values v ° and the slopesS v * were obtained in each case, and their significance has been discussed briefly. The mean apparent molal volumes v of the ternary systems were also calculated, and the predictive accuracy of Ward and Millero's modified Young's rule for v was found to be comparable to that for other electrolyte-nonelectrolyte solutions. For the system H2O-sucrose-urea, an additivity rule based simply on total molality predicted v with similar accuracy.Deceased January 15, 1976.  相似文献   
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The results of an ab initio study of the vibronic and rotational structure in the 2Π state of HNO+ are presented. It is shown that the absorption spectrum at 7200 Å observed by Herzberg could be caused by the transition from the ground to the first excited electronic state of HNO+  相似文献   
40.
We present a uniform version of Di Nola Theorem, this enables to embed all MV-algebras of a bounded cardinality in an algebra of functions with values in a single non-standard ultrapower of the real interval [0,1]. This result also implies the existence, for any cardinal α, of a single MV-algebra in which all infinite MV-algebras of cardinality at most α embed. Recasting the above construction with iterated ultrapowers, we show how to construct such an algebra of values in a definable way, thus providing a sort of “canonical” set of values for the functional representation.  相似文献   
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