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1.
. - ; K , . , , . - , - . . , , : , - ( ) . -, . , . 45 . 3 (1951).  相似文献   

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It is shown experimentally that after annealing samples of NaCl the thermoluminescence in the high-temperature maxima not only increases, which is in agreement with the results of other authors, but that simultaneously the thermoemission decreases. It follows from a discussion of the results that this effect is probably caused by the formation of a surface layer, which takes place during the evaporation of the sodium and both prevents the rise of the electrons from the crystal and the vacancies left in it by the sodium increase in the concentration of theV centres and thus the probability of luminescence.
, NaCl - , , , , , - , , V- ( ).


The authors thanks K. Listoová for carefully carrying out the measurements.  相似文献   

5.
On the basis of general summation formulae for light reflected and transmitted by a thin film the author derives formulae for a thin dielectric film, for a thin metallic film and for a system of thin dielectric films. This solution is based on Stokes's principle of reversibility, which is the idea unifying the cases into one theory. In conclusion he gives the solution of a general case, dealing with light reflected and transmitted by a system of thin dielectric and metallic films.
, . , , . , .
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The paper gives new results obtained in research into and the development of chain bi-refringent filters described by the author [1–4, 6].
, , [1–4, 6].
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The paper solves the problem of gas ionization in a discharge path in a very dilute gas, where the free path of the electrons is much larger than the dimensions of the path and the transit time of the electrons between the electrodes is of the order of the period of the applied h-f voltage. It was found that for a certain ratio of the transit time of the electrons between the electrodes in the discharge path to the period of the h-f oscillation, resonance occurs when the wattless current component is zero. The electron density rises in the path and thus also the gas ionization.
, , , . , , . , .


In conclusion, the author would like to thank F. Benda for preparing the equipment, M. Kivánek for preparing the equipment and some of the measurements, and A. Hrdá for the measurements and for working out the case with equally large a-c and d-c voltages within the framework of her thesis.  相似文献   

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Zusammenfassung Die spektrale Abhägigkeit der photodielektrischen Eigenschaften der lumineszierenden Zinkkadmiumsulfide verschiedener Zusammensetzung zeigt, da eine Beimengung von Kupfer das Eintreten von Zuständen mit groer Polarisierbarkeit hervorruft, die eine Änderung der realen Komponente der Dielektrizitätskonstanten zur Folge haben. Die Kupferkonzentration kann dabei so gering sein, da sie in der Lumineszenzemission gar nicht zur Geltung kommt. Die Infrarotmaxima der Verluste entsprechen Niveaus, die von anderen Autoren und mit anderen Methoden festgestellt wurden. Das Maximum des Exzitationsspektrums im Bereiche des Ausläufers der Absorptionskante hängt mit dem Maximum der Änderung der realen Komponente der Dielektrizitätskonstante zusammen.
-
- , , . , . , . .


Nunmehr im Physikalischen Institut der Karlsuniversität, Prag.  相似文献   

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, . . . , , . , . , . .
Betatron oscillations in an accelerator with a general field I
The paper gives a linear theory of equilibrium trajectories in an accelerator with a generalized magnetostatic field, the components of which are defined on a general rotation surface. Equations of motion of the particles in natural coordinates are derived with respect to the change in energy and dissipative force. A system of equilibrium trajectories is found in the general form. Conditions for the field components on the reference surface, necessary for the existence of equilibrium trajectories, for the conservation of their geometric similarities and for maintaining the constancy of the frequencies of the betatron oscillations, are derived. A condition is also derived which must be satisfied by the reference surface in order to conserve constant circular frequency of the particles. It is seen that it is not possible to find a field for an accelerator with an exactly constant circular frequency and with constant frequencies of the betatron oscillation in the relativistic energy region. An ultra-relativistic cyclotron with such properties is realizable.
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. . , .
The influence of a strong high-frequency field on the stratification of the positive column of a D-C glow discharge
An experimental study is made of the damping of moving striations in a d-c glow discharge by a strong high-frequency field. The results of measurement are in agreement with existing conceptions on the production and mechanism of propagation of moving striations. Apart from the process of damping the paper also describes the standing stratification of the positive column of a d-c discharge as a result of a superposed high-frequency discharge.


.  相似文献   

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(GaSb), - 120–340 °K. : E2=(0,773–0,75.10–6 T 2) ., - .  相似文献   

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The potentials of an electromagnetic field of multipoles in a dielectric, which is realized by a dielectric sphere having a perfectly conducting surface, are derived. The diagonal values of the energy for thez component of the angular momentum and the square of the angular momentum of the field are determined and also the ratio between thez component of the angular momentum and the energy and the ratio between the square of the angular momentum and the square of the energy. It is shown that the total angular momentum can be divided in the usual way into orbital and spin parts but that these parts cannot be interpreted as the orbital and spin angular momentum because their eigenvalues cannot be the eigenvalues of any operator of infinitesimal rotation. In the commutation rules of a multipole field the vector character of the field is to a certain extent suppressed and the spin of the photon in a state with a certain value of the energy, parityz component of the angular momentum and the square of the angular momentum is not defined.
, . ,z— , , z— . , , , , , - . , ,z— .


In conclusion the author thanks Dr. . Muziká for directing the work, F. Samek for valuable remarks and discussion and J. Kvasnica for help in preparing the paper for publication and for adding a number of remarks.  相似文献   

17.
The self-regulation of an inert gas shielded metal welding arc is dealt with briefly. A thermodynamic equation is derived for the self-regulation of such an arc.
. .
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18.
. , . c . , , . c ; .
The magnetoresistance in zinc-manganese ferrites in the vicinity of the Curie point
The paper describes an exact method for measuring the adiabatic and isothermal magnetoresistant effects in ferrites. It gives the results of studying the temperature dependence of the magnetoresistant effect, which is negative near the Curie point in ferrites and the temperature dependence of which has a maximum of absolute values inT c . It is also shown that the pronounced maximum of the adiabatic magnetoresistant effect is to a certain extent caused by the magnetocaloric effect. When measuring the dependence of the magnetoresistant effect on the field strength for a temperature equal toT c , certain small deviations from the theoretically assumed dependence were found; the influence of different factors on these deviations is discussed and a proposal for their explanation is given in analogy to the results known for metals.


[1].

., ., . . . , . . , . . . . .  相似文献   

19.
. , .
The coherent radiation of synchrotron electron clusters in a closed resonator
A study is made of the electromagnetic interaction of electrons in thin relativistic clusters during coherent radiation in a synchrotron. The magnitude and form of the tangential component of the force, acting on an isolated electron of a cluster of electrons, is expressed.


. . .  相似文献   

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