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1.
Deviations of nuclear magnetic moments of oddA nuclei from the Schmidt lines are explained by configuration mixing. The general results obtained are applied to several nuclei and the magnitudes of the admixture coefficients necessary to explain the deviations are estimated. The results show that the deviations can be successfully explained only for those nuclei, in which possible configuration admixtures give contributions to the magnetic moment linear in the admixture coefficient.
A . , . , , , .


This work was done as a diploma thesis at the Faculty of Technical and Nuclear Physics, Technical University, Prague.

In conclusion I want to thank Dr. L. Trlifaj for suggesting this subject and for his guidance in its realization.  相似文献   

2.
Using Van Vleck's modification of the Heisenberg theory of ferro-magnetism for substances with arbitrary spin per atom, a generalization of the theory is given for the case of ferrimagnetics, anti-ferromagnetics and thin films with an arbitrary number of sub-lattices and with arbitrary spin per atom. The exchange part of the energy operator is formulated by means of rotated spin operators. The theory contains the quantum-mechanical generalization of non-quantum theories given by Néel and later generalized by Yafet and Kittel. It also contains the theory of thin films proposed recently by the author. The magnetization laws are completely analogous to the relations derived from the theory of molecular fields. The constants of the molecular fields are interpreted by means of exchange integrals. For the special case of spin S=1/2the theory agrees with the results of the work of Vlasov and Imuchametov for ferrimagnetics and anti-ferromagnetics and with the author's for thin films.
,
, , , . . - , . , . , . . S=1/2 .
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3.
Path integral representations for Fokker-Planck (FP) equations, described by the random walks (RW) and the generalized random walks (GRW), are given. The GRW is a generalized one from the usual random walks to study non-linear, non-equilibrium processes. The GRW includes some memory effects and couplings through the jumping probabilities. To derive the path integrals of the processes, a transformation of probability, scalings of site (space) and step (time) are performed on the GRW. By a function in the exponent of the path integrals for the FP equation obtained by the RW or the GRW, a Lagrangian giving most probable path is introduced. From the Lagrangian, an effective Hamiltonian is deduced.  相似文献   

4.
5.
The crucial problem of physics was first formulated by Democritus in the 5th century BC: to find the or smallest uncuttable bits of matter. That has not changed ever since. Among the current candidates are electron and positron, the least expensive of today's bona fide . Experimental tests of their non-compositeness by precisely measuring the gyromagnetic ratios of the individual trapped particles are reviewed.You know, it would be sufficient to really understand the electron.Albert Einstein  相似文献   

6.
7.
, , . , . .
The damping of particle oscillations in a general field with periodic structure I
A liner theory is derived, discussing the dynamics of particles in the region of an equilibrium orbit in a general electromagnetic field, which forms a periodic system. The total particle damping is determined from the Hamiltonian found and from dissipative forces brought out by a classical reaction radiation. Relations for the damping of the synchrotron oscillations are derived from the study of the appropriate phase space.
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8.
Zusammenfassung In dieser Arbeit werden die Erscheinungen der normalen und anomalen, durch Infrarotstrahlung verursachten und von uns schon früher an diesen Photokatoden beobachteten Ermüdung von Silber-Cäsium-Photokathoden untersucht. Diese Erscheinungen wurden an durchsichtigen sowie undurchsichtigen, durch verschiedene Technologien zubereiteten Photokathoden festgestellt. Es wurden Messungen der Strahlungsintensitäts-, Temperatur- und Spektralverteilungsabhängigkeit der normalen und anomalen Ermüdung durchgeführt. Es werden die Ursachen der Unübereinstimmigkeit im Vergleich mit Arbeiten von De Boer und Teves besprochen. Ferner wurden die Zeitverläufe der Ermüdung bei der Abwechslung der Bestrahlungs- und Dunkelzyklen studiert.
-
, , . , . , . . .
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9.
We demonstrate with the example of Cahn-Hilliard dynamics that the macroscopic kinetics of first-order phase transitions exhibits an infinite number of constants of motion. Moreover, this result holds in any space dimension for a broad class of nonequilibrium processes whose macroscopic behavior is governed by equations of the form /t = W(), where is an order parameter,W is an arbitrary function of , and is a linear Hermitian operator. We speculate on the implications of this result.  相似文献   

10.
11.
The dependence of the magnetostriction constant of different materials in the form of a wire on the elastic elongation was measured. With pure nickel the magnetostriction constant is independent of the elastic deformation. All three alloys of iron and nickel and the triple alloy Fe-Ni-Co exhibit a linear dependence on the deformation, which differs for different crystallographic texture. In two iron-nickel alloys the dependence of the magnetostriction constants of the single crystal on the elastic deformation was calculated from measurements on polycrystals having different crystallographic textures. In the triple alloy Fe-Ni -Co a considerable linear decrease in the volume magnetostriction with the elastic elongation was also found. The observed changes can be explained by assuming the influence of the lattice deformation on the spinorbital interaction in alloys.
-
. . - Fe-Ni-Co , . - . , Fe-Ni-Co . - .


A preliminary report on some of the results of this paper was given at the conference on magnetism in Kyoto (Japan) in September 1961.

In conclusion the authors thank Z. Frait C. Sc. and S. Libovický for remarks, J. Míová for help in the measurements, members of the chemical department of our institute for annealing and analyzing the samples and members of the Metal Research Institute in Panenské Beany for their exceptional helpfulness in preparing the wires.  相似文献   

12.
This paper describes the measured dependence of the lattice spacings of equilibrium Al-Ag solid solutions on temperature and composition. The form of the lattice spacing composition curve is found to differ considerably from that for the supersaturated Al-Ag solid solutions. The differences between the spacings of equilibrium and quenched Al-Ag solid solutions plotted against the electron concentration yield a curve similar to that constructed from the analogous measurements on Al-Zn given by Ellwood. The differences can be attributed to the influence of changes accompanying the increased solute clustering introduced by quenching the solid solutions into the supersaturated state.
Al-Ag . , Al-Ag . Al-Ag, (. . , ), Al-Zn, , . , .


The author wishes to express her thanks to Ing. J. Lagek for his care in carrying out the chemical analysis of the aluminium-silver alloys. The careful density measurements of these alloys made by J. Bednfi [are greatly appreciated.  相似文献   

13.
, , . .
Influence of pair forces on the giant resonance energy
The influence of various nucleon-nucleon forces on the giant resonance energy is investigated with the help of the sum rules. The dependence of the contribution of exchange forces to the integral cross-section of the gamma quantum absorption on the number of protons and neutrons is obtained for light nuclei.
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14.
15.
We analyze the long time behavior of an infinitely extended system of particles in one dimension, evolving according to the Newton laws and interacting via a non-negative superstable Kac potential (x)=(x), (0, 1]. We first prove that the velocity of a particle grows at most linearly in time, with rate of order . We next study the motion of a fast particle interacting with a background of slow particles, and we prove that its velocity remains almost unchanged for a very long time (at least proportional to –1 times the velocity itself). Finally we shortly discuss the so called Vlasov limit, when time and space are scaled by a factor .  相似文献   

16.
The well-known connection between the SU(2) gauge theory and the massless 4 theory is extended to theories with nonzero mass. Elliptic solutions of these massive theories are given. These are of the plane-wave variety, with independent variable u=p·x where p is a constant four-vector. They depend on a free parameter k. Two of the solutions are generalized plane-waves while the third describes fluctuations about the vacuum solution.  相似文献   

17.
18.
As is known, the second approximation in the calculation of the partition function by the traces method of ferromagnetic thin films gives wrong results for the coordination number equal to eight. In order to obtain correct results even for this case, the third order approximation of the partition function is developed and thus the magnetic properties of body-centred cubic iron thin films are studied. The dependence of the Curie temperature on the thickness, for different values of the ratio between the anisotropy constant and the exchange energy between two neighbours, is discussed. A value can be chosen for this ratio such that the thin film becomes ferromagnetic only for a thickness greater than a definite value.
, . , , (Fe). . , - .
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19.
20.
The paper deals with the problem of the anomalous divergence of an infinite geometric series of complex amplitudes, pointed out by Berning. It is shown that the paradox is of a formal mathematical nature and has no consequences for multiple beam interference as a method of derivation.
, . , - .
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