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1.
The theory of double quantum transitions of the M=±2 type, with regard to inhomogeneously broadened spin systems is studied in this paper with the approximation 2T2T3 1. We suppose that the inhomogeneous broadening is formed by an inhomogeneous crystal field. The obtained results describe the magnitude of absorption as a function of the h.f. power and also describe the shape of the absorption curve. It is demonstrated that in inhomogeneously broadened spin systems the absorption curve of double quantum transitions has the form of the difference of two different Lorentz's curves and that at the saturation ( 2T2T1 1) the absorption increases with the cube of the h.f. field intensity. The shape of the curves is expressed by means of phenomenological relaxation constants of the system.
M=±2 2T2T3 1. , - . . , ( 2T2T1 1) . .
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The method of sliding photomultipliers was used to study the connection between two forms of the positive column in oxygen — the so-called low-gradientT-form and the highgradientH-form — and the presence of moving striations in the positive column. It was shown that in theT-form of a positive column striations are always present which move from the cathode to anode with a velocity of several thousand metres/sec. The highgradient form of theH-positive column, on the other hand, is not striated. The non-single-valuedness of the value of the longitudinal electric field in a discharge in oxygen is thus explained by the presence or absence of phenomena of a time variable character.
— - H - — . , - , /. , , . , , , .
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4.
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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A variety of rigorous inequalities for critical exponents is proved. Most notable is the low-temperature Josephson inequalitydv +2 2–. Others are 1 1 +v, 1 1 , 1,d 1 + 1/ (for d),dv, 3 + (for d), 4 , and 2m 2m+2 (form 2). The hypotheses vary; all inequalities are true for the spin-1/2 Ising model with nearest-neighbor ferromagnetic pair interactions.NSF Predoctoral Fellow (1976–1979). Research supported in part by NSF Grant PHY 78-23952.  相似文献   

9.
Résumé Dans la présente étude, on trouve un bref résumé des travaux de l'auteur, de ses collègues et collaborateurs, concernant l'utilisation des résonateurs dans l'acoustique architecturale. On explique tout d'abord le problème de l'inpluence des résonateurs sur la durée de la réverbération des salles. Se basant sur des considérations théoriques, l'auteur déduit le critère de l'emplacement le plus favorable des matières absorbant le son dans le résonateur même et discute la possibilité de l'absorption totale du son par le résonateur. Dans le cas des systèmes de résonateurs pareils disposés régulièrement sur les murs, le diapason pouvant être obtenu d'une importante absorption est relativement faible. En se servant de systèmes résonants d'absorption comportant plusieurs couches de résonateurs, reliés en série, le diapason de l'absorption importante peut être notablement élargi. L'auteur explique la corrélation du coefficient d'absorption et de l'angle d'incidence de l'onde sonore. En conclusion, on mentionne des exemples de l'utilisation pratique des résonateurs d'absorption les plus simples pour obtenir la caractéristique de l'absorption de fréquence exigée. On discute aussi le problème de l'influence des vibrations simultanées de la paroi extérieure du système de résonance sur la caractéristique de l'absorption du son.
. . . , , . , , . . ; .
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10.
, . 20–1000 keV Sc, Fe, Cu, Mo, Cd La.
The radiative capture of a neutron on Sc, Fe, Cu, Mo, Cd and La nuclei
The energies and intensities of the transitions of a compound nucleus, produced by the capture of a neutron, were measured by means of a single-crystal scintillation spectrometer. The region of energies 20–1000 keV was measured on Sc, Fe, Cu, Mo, Cd and L a nuclei.
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11.
Zusammenfassung Unter der Voraussetzung, daß das Ahtivierungsfeld für die reversible Bewegung der Blochschen Wände dem Maxwellschen Verteilungsgesetz unterliegt, wird die Entstehung des Maximums der inneren Reibung im Wechselfeld theoretisch erläutert. Weiter wird die Lösung der Differenzialgleichung für die Bewegung einer Blochschen Wand bei gleichzeitiger Wirkung des Wechselfeldes und der Torsionsbeanspruchung gegeben. Die Messung bei einigen Torsionsfrequenzen ermöglicht die Bestimmung gewisser mikroskopischer Konstanten.
, . . .
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, , . , . .
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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14.
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.
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. . - 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   

15.
Let t be an analytic solution of the Schrödinger equation with the initial condition . Let t be the solution of the Schrödinger equation with the initial condition =, where is an analytic function. When 0, then t (x) t (x)1 ( t (x)), where t (x) trajectory starting from x. We relate this result to Feynman's sum over trajectories and complex stochastic differential equations.  相似文献   

16.
Zusammenfassung Nach Zalm sind die Kristalle von ZnS mit einer dünnen Halbleiterschicht bedeckt, aus der auf Grund des Tunneleffekts Elektronen in den Kristall eindringen können. Im vorliegenden Artikel wird vorausgesetzt, da die Elektrolumineszenz bei der Rekombination dieser Elektronen mit den ionisierten Aktivatorzentren eintritt, die sich im Kristall zu Beginn eines jeden Zyklus vorfinden, und die Folgen dieser Voraussetzung werden mit den experimentell erhaltenen Daten verglichen.
ZnS
ZnS , . , , ; .


Dieser Artikel entstand aus einer Diplomarbeit, die im Physikalischen Institut der Tschechosl. A. d. W., Prag, ausgearbeitet wurde.

Abschlieend möchte ich RNDr. Miroslav Trlifaj für seine zahlreichen wertvollen Hinweise wie auch für sein Interesse an dieser Arbeit danken.  相似文献   

17.
The eight-vertex model is equivalent to a solid-on-solid (SOS) model, in which an integer heightl i is associated with each sitei of the square lattice. The Boltzmann weights of the model are expressed in terms of elliptic functions of period 2K, and involve a variable parameter . Here we begin by showing that the hard hexagon model is a special case of this eight-vertex SOS model, in which =K/5 and the heights are restricted to the range 1l i4. We remark that the calculation of the sublattice densities of the hard hexagon model involves the Rogers-Ramanujan and related identities. We then go on to consider a more general eight-vertex SOS model, with =K/r (r an integer) and 1l ir–1. We evaluate the local height probabilities (which are the analogs of the sublattice densities) of this model, and are automatically led to generalizations of the Rogers-Ramanujan and similar identities. The results are put into a form suitable for examining critical behavior, and exponents, , are obtained.Supported by the Guggenheim Foundation and in part by the National Science Foundation, grant MCS 8201733.  相似文献   

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The paper explains the theory of modelling electrostatic fields by a resistance network. The conditions, which the resistance network must satisfy, are derived and the question of modelling electrodes of different shapes is solved. The finished network and the results obtained on it when modelling a jet for a linear h-f accelerator of electrons are described. Particular attention is paid to the influence of a space charge, the modelling of which is an advantage of this method.

1- , 1964., , .

. .  相似文献   

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