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1.
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   

2.
The paper gives the values of the optical constants of thin films of germanium obtained by evaporating germanium in a vacuum onto glass slides in the region of 0·35–0·78 for an index of absorptionk and 0·35–2·5 for refractive indexn. The results are compared with the values obtained by other authors and with the values ofn andk for single crystals. It is shown that these values for thin films and single crystals slightly differ quantitatively but agree fairly well qualitatively, which had not been sufficiently the case in previous papers.
, , 0,35 0,78 k 0,35–2,5 n. n, k . , , , , .
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3.
The change in integrated intensity of the (200) reflections of a solid solution during the formation of G.P. zones was measured and compared with the change in the character of the diffuse streaks corresponding to them. It was found that the. formation of G.P. zones does not lead to a decrease in primary extinction despite the great changes in the distribution of the copper atoms. It was shown that the formation of a precipitate accompanied by the formation of crystallographically incoherent boundaries greatly decreases the primary extinction.
. II. 1-u 4%: [. . ]
(200) . . , . , . . , . , , , .
  相似文献   

4.
Zusammenfassung Es wurde der Einfluß eines Bombardements mit Stickstoffionen vor der Erregung untersucht und gezeigt, daß die Stiekstoffatome eine große Rolle bei der Entstehung des Emissionsmaximums bei 150° spielen.
-
, 150°C.
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5.
. . . — - . . . , . , .
Temperature dependence of the young's modulus of the Al-Zn alloys and its influence upon the metastable coherent phase diagram
The paper describes the measurements of the temperature dependence of Young's modulus for several Al-Zn alloys. The moduli were measured by the method of a composite oscillator at resonance frequencies of about 100 kHz. When decreasing the temperature from the state of homogeneous solid solution, the undercooling phenomena cause a hysteresis effect. Young's modulus decreases approximately linearly with increasing atomic fraction of zinc at 390C. The determined temperature and concentration dependence was used for thermodynamic calculation of the form of metastable coherent solubility gaps by which the separation of the solid solution into coherent zones can be described.


B. K. Kardaev, S. P. Nikanorov,A. F. Ioffe Physico-Technical Institute, Acad. Sci. U.S.S.R., Politechnieskaja 26, Leningrad K- 21, U.S.S.R.

J. Laek,Institute of Solid State Physics, Czechosl. Acad. Sci., Cukrovarnická 10, Praha 6, Czechoslovakia.  相似文献   

6.
7.
The paper describes a new method for determining the parameters in the equation for ferromagnetic resonance — the internal effective field, the spectroscopic splitting factor and the saturation magnetization in polycrystalline magnetically isotropic ferrites. Relations are derived for calculating these parameters by means of the values of the resonance external static fields, which are obtained by measuring on samples having different geometrical shapes and differently arranged static and microwave magnetic fields. The advantages and disadvantages of the method and remarks on the experimental method are given. The paper ends with an example of measurement.
: , . , . . .


The determination of the saturation magnetization of ferrites by the method described here was reported on at the Seminary on Ferrites in Microwave Technique, held by the Institute of Technical Physics, Czechoslovak Academy of Sciences, and the Research Institute of Communications Engineering of A. S. Popov, on November 25, 1959.  相似文献   

8.
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The influence of the emission properties of an anode on the characteristics of GM counters
The hitherto unknown mechanism of the production of false pulses is investigated and its influence on the characteristics of counters is discussed.
  相似文献   

9.
A study is made of the influence of successive asymmetrical magnetization reversal on the magnetic state of open samples, where the macroscopic demagnetization field has a significant effect during magnetization reversal and leads to a sort of rotation of the asymmetrical loops performed one after another. This effect is similar to reptation, which was studied experimentally by Nguyen van Dang [1–4] and theoretically explained by Néel [5, 6]. The quantitative expression of the rotation of asymmetrical loops in open samples as a function of the number of loops and amplitude of the disymmetry is similar to that with the reptation effect.
, , . , . .


In conclusion the authors thank Dr. L. Valenta, C. Sc., and Z. Málek, C. Sc., for valuable discussions.  相似文献   

10.
The paper deals with the collective behaviour of electrons which rotate in a magnetic field used in a betatron. It is shown experimentally that there exists strong interaction between the electrons, which leads to the rapid formation of the equilibrium state with characteristic distribution of the charge density in the cross-section of the toroidal beam. The corresponding relaxation time is of the order of 1 sec. A statistical theory of the equilibrium beam is elaborated. Its main result is that the effective radius of the beam is a function of two parameters, one of which is proportional to the thermal energy of the electrons and the other to the perveance of the beam. The charge contained in a toroidal beam of given effective cross-section is equal to the product of the charge the beam would contain at zero temperature and a coefficient, which is a function of the temperature of the beam. Its value is unity at zero temperature and rapidly decreases with increasing temperature. The cause of cooling of the beam is shown.
, . , , . 1S. . , , — I/(E0/q)3/2 (I — , 0 — q ). , , , , , . . .


Now Institute of Vacuum Electronics, Czechosl. Acad. Sci., Prague.

In conclusion the author thanks J. Luká and L. Hyttych for invaluable help in the experiments, A. Rajský for constructing the electronic apparatus and J. Sokol for preparing the miniature probe.  相似文献   

11.
The current and logarithm-of-the-current distributionsn(i) andn(ln i) on bond diluted two-dimensional random-resistor networks at the percolation threshold are studied by a modified transfer matrix method. Thek th moment (–9k8) of n(ln i) i.e., ln i&k, is found to scale with the linear sizeL as (InL)(k). The exponents (k) are not inconsistent with the recent theoretical prediction (k)=k, with deviations which may be attributed to severe finitesize effects. For small currents, ln n(y), yielding information on the threshold below which the multifractality of (i) breaks down. Our numerical results for the moments of the currents are consistent with other available results.  相似文献   

12.
The paper deals with the motion of 90° wedge domains in BaTiO3 in an alternating field of 50 c/s. The critical field, the positional hysteresis loops with double asymmetry, the production of wedges with polarization perpendicular to the field and 180° substructure in the wedges were studied. The differences between the behaviour of the wedges and the individual 90° walls are pointed out which are caused by differences in the energy balance of these formations and by different interactions with 180° processes. The upper limit of contribution of the wedge motion to the initial permittivity is estimated. The results are discussed from the phenomenological point of view.
90° BaTiO3
90° BaTiO3 , 50 Hz. , , , , , , 180° . 90° , 180° . , . .
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13.
Every normal, faithful, self-adjoint functional on a von Neumann algebraA canonically determines a one-parameter-weakly continuous *-automorphism group (the analog of the modular group) and a canonical 2 grading onA, commuting with . We show that the functional satisfies the weak super-KMS property with respect to and Furthermore, we prove that and are the unique pair of a-weakly continuous one-parameter *-automorphism group and a grading of the algebra, commuting with each other, with respect to which is weakly super-KMS. The above results thus provide a complete extension of the theory of Tomita and Takesaki to the nonpositive case.Supported in part by the National Science Foundation under Grant DMS-8922002.  相似文献   

14.
In connection with another article by the author, we show how it might be possible to travel faster than the speed of light. We show that for clocks and rods moving faster than the speed of light, we get instead of time dilation and Lorentz contraction, respectively, time contraction and Lorentz expansion, respectively. It is shown that this paper is in confirmation with earlier articles dealing with this subject.  相似文献   

15.
This paper describes the VFS-3M videophotometric system designed for automatic remote recording of images and parameters of optical radiations following lightning discharges from aboard the Russian segment of the International space station. The characteristics of the system and the possibilities of recording such types of radiation as Red Sprites and Blue Jets are given.  相似文献   

16.
17.
18.
The author has recently proposed a quasi-classical theory of particles and interactions in which particles are pictured as extended periodic disturbances in a universal field (x, t), interacting with each other via nonlinearity in the equation of motion for . The present paper explores the relationship of this theory to nonrelativistic quantum mechanics; as a first step, it is shown how it is possible to construct from a configuration-space wave function (x 1,x 2,t), and that the theory requires that satisfy the two-particle Schrödinger equation in the case where the two particles are well separated from each other. This suggests that the multiparticle Schrödinger equation can be obtained as a direct consequence of the quasi-classical theory without any use of the usual formalism (Hilbert space, quantization rules, etc.) of conventional quantum theory and in particular without using the classical canonical treatment of a system as a crutch theory which has subsequently to be quantized. The quasi-classical theory also suggests the existence of a preferred absolute gauge for the electromagnetic potentials.  相似文献   

19.
Inasmuch as physical theories are formalizable, set theory provides a framework for theoretical physics. Four speculations about the relevance of set theoretical modeling for physics are presented: the role of transcendental set theory (i) in chaos theory, (ii) for paradoxical decompositions of solid three-dimensional objects, (iii) in the theory of effective computability (Church-Turing thesis) related to the possible solution of supertasks, and (iv) for weak solutions. Several approaches to set theory and their advantages and disadvatages for physical applications are discussed: Canlorian naive (i.e., nonaxiomatic) set theory, contructivism, and operationalism. In the author's opinion, an attitude of suspended attention (a term borrowed from psychoanalysis) seems most promising for progress. Physical and set theoretical entities must be operationalized wherever possible. At the same time, physicists should be open to bizarre or mindboggling new formalisms, which need not be operationalizable or testable at the lime of their creation, but which may successfully lead to novel fields of phenomenology and technology.  相似文献   

20.
Relations are derived for the elastic stress field around a linear dislocation in an infinite medium with general anisotropy. The strongly deformed material around the core of the dislocation is cut out in the shape of an elliptic cylinder. The conditions of a free surface are used on the boundary thus formed. The calculation of the field around a crack in a crystal, the model of which was proposed by Fujita in [9], is given as an example.
. , , , . , [9] .


The author thanks Dr. F. Kroupa for valuable discussions and all-round help in solving the problem and Z. Hemanová for performing the numerical calculations.  相似文献   

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