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141.
We consider the possibility of finding experimental evidence of the fifth force with the measurement of a phase shift of neutron beams via an interferometric apparatus and also a possible rotation of the polarization plane of polarized neutron beams when torsion is introduced in a gravitational field.  相似文献   
142.
143.
The states of 104Pd, populated in the EC-β+ decay of the ground ( J π = 5+) and metastable ( J π = 2+) states of 104Ag, have been investigated in the framework of the proton-neutron interacting boson model, extending a previous analysis to take into account the newly appeared experimental data. All positive-parity states up to an excitation energy of 3 MeV and spin in the range J = 1-6, fed by more than 0.3% in the decay of the parent nucleus, have been considered. As a result, strong evidence has been found for interpreting most of these states as states of collective nature having a quite pure full- or mixed-symmetry character and, in particular, for identifying the 1+ level at 2276 keV as the lowest 1+ mixed-symmetry state.  相似文献   
144.
Several illusions of vision are considered on the basis of a neurophysiological holographic model of visual perception at the level of the eye’s and the retina. It is suggested that the eye’s optical system forms a spatial spectrum of the observed object rather than its image on the retina. The spectrum is encoded by active anisotropic quasi-crystalline structures of rod rhodopsins and cone iodopsins, and a complex Fourier hologram of the observed object consisting of two quadrature components is recorded. The holographic hypothesis is confirmed by the results obtained by digital simulation.  相似文献   
145.
Energy bounds of knotted and linked vortex states in a charged two-component system are considered. It is shown that a set of local minima of free energy contains new classes of universality. When the mutual linking number of vector order parameter of vortex lines is less than the Hopf invariant, these states have lower lying energies.  相似文献   
146.
Bismuth, antimony and its alloys are the typical representatives of a class of semimetals, which electric conductance is lower in 102-103 times, than of usual well conducting an electrical current metals. The alloys bismuth with antimony have semi-conductor properties in wide area of compositions at temperatures below 77 °K. The semimetals are rather perspective materials from the point of view of their probable application in various devices [1,2,3].In present time the semimetal alloys BiSb have wide application in thermoelectric generators and refrigerators. In work [3] the opportunity of use of semimetals BiSb with percentage content of Bi and Sb from 8 % up to 25 % was shown as high-sensitivity and of small inertion indicators of the mm range radiation where thermoelectric effect is used. The principle of action of such indicators is based on occurrence of temperature gradient in a semimetal crystal BiSb that has two contacts of the various area with flowing electrical current. Basic element of such device is the dot contact metal - semimetal. One of the main characteristics is volt-watt sensitivity of metal-semimetal BiSb contact which calculating is shown in present work.  相似文献   
147.
A derivation schema in an axiomatic theory is defined as a finite sequence of analysis of applications of rules and axioms. A derivation by a schema U is any derivation whose list of analyses of applications of rules and axioms is precisely U. A derivation schema is admissible if a corresponding derivation can be constructed. Let G be a Hilbert-type axiomatic theory. The following problems are considered: a) to decide whether a given derivation scheme is admissible in G; b) to decide whether a formula is derivable by a given derivation schema in G. In the usual formulations of the predicate calculus without equality, the first problem is shown to be decidable, the second undecidable.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova Akad. Nauk SSSR, Vol. 174, pp. 132–146, 1988.  相似文献   
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149.
Exact formulas for the angular eikonal of decentered and oblique conicoids are obtained based on the analysis of the properties of conicoids and angular eikonals. The case of a paraboloid is considered separately. Exact formulas for the angular eikonal open the possibility of construction of an exact theory of aberrations.  相似文献   
150.
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