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1.
The basic equations of the dynamics of the continuous distribution of dislocations analogical to Maxwell's equations are derived in a series of papers I, II, III. The analogy of the elastic and electromagnetic fields is analyzed. In part I the basic equations of the continuous distribution of dislocations are derived for the dynamic case (especially for small deformations and for the Poisson ratio equal to zero in a continuum, infinite with respect to space and time, from the variational problem by means of the formal apparatus of the special theory of relativity.
I.
, . . , , .
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2.
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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3.
In order to demonstrate the capabilities of white-light interferometry depth profiling (WLI-DP) for ancient coinage assessment, we investigated a series of notorious 1786 gold coins, bearing Louis XVIs horned effigy, and allegedly minted in Strasbourg. Scanning electron microscopy as well as WLI-DP observations unambiguously indicate that both previously differentiated single- and double-horned varieties originated from a unique minting tool. Moreover, from topological measurements, we infer that single-horned coins, rather than wearing out into double-horned coins, proceeded from the latter variety during minting by progressive failure of an already altered die. Whereas present observations do not exclude initial forgery, they suggest that protrusions resulted from progressive incidental in-service die deterioration. PACS 81.70.Fy; 07.60.Ly; 61.16.Bg; 81.40.Pq  相似文献   

4.
The magnetostriction constant of nickel was measured as a function of plastic deformation up to an elongation of 30%. The values of the magnetostriction constant in deformed samples deviate considerably, a fact which cannot be explained by errors of measurement. The absolute value of the magnetostriction constant decreases with increasing plastic deformation (by around 5%).
30% . , . ( 5%).


In conclusion the authors thank J. Kaczér, C. Sc. and B. esták, C. Sc. for carefully reading the paper and for their remarks, J. Míová for help in the measurements and workers of the chemical department of our Institute for careful preparation of the samples.  相似文献   

5.
In paper [1] Fang derived an expression for the complex conductivity of plasma assuming that the distribution function of the electrons is Maxwellian and the collision frequency is directly proportional to their velocity. Since the assumptions are approximately satisfied in the positive column of a d-c glow discharge in Ne, the applicability of Fang's relation is investigated for this case.
[1] , . , .
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6.
A study is made of the Shockley surface states in a linear chain of equal atoms, joined by alternately strong bonds. If the simple MO LCAO method is used, which considers the exchange integrals between nearest neighbours and next nearest neighbours, we get the surface states for a semi-infinite chain if the stronger bond is interrupted. The connection between Shockley and Tamm surface states is shown and the hypothesis is put forward that the condition for the existence of Shockley surface states has a generally simple physical interpretation, the validity of which is proved on the models of a semi-infinite crystal studied up to now.
, . MO LCAO, , , . , , , .
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7.
A theory of the azimuthal bunching of electrons injected into the betatron is presented and compared with the experiments described in [1]. The bunching is treated as a small perturbation of the stationary beam.The stationary injected beam is replaced by the corresponding equilibrium beam of the same perveance so that the angular velocity spread of the injected electrons is proportional to the square root of the injection perveance.Self-consistent wave solutions for the perturbation of the stationary solution are then found. Equations giving the amplification of small density or energy disturbances along the beam are derived. These disturbances are assumed to be introduced by density or velocity modulation of the injected beam. The condition for the spontaneous occurrence of bunching is deduced by assuming that the disturbances do not vanish even when there is no modulation of the injected beam. The resulting expressions for the threshold perveance and the rise-time of the disturbance are in reasonably good agreement with the experiments. Such agreement may be considered as further verification of the statement made in [1] that the amplification of the disturbances is caused by the negative mass instability mechanism.
, .
, . , [1]. . . , , . . , ., . , , . . , , [1].
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8.
9.
. .
The influence of fringing on betatron oscillations in an accelerator with a sectioned magnet II
The influence of stray fields at the edges of pole pieces on the deformation of equilibrium trajectory and betatron oscillations is studied. A new definition of the effective length of segments for the approximative solution is given.
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10.
The wave function and spin are shown to be attributes of the dynamics which is a dominant structure of the quantum mechanics. A self-consistent force field (not the quantum axiomatics) appears to be responsible for quantum effects. The field can escape from the matter and produce pairs.  相似文献   

11.
The paper describes a double-crystal monochromator unit. The influence of vertical divergence of the beam on the luminosity and degree of monochromatization is discussed in detail and experimentally proved. Finally, the author shows how to apply a double-crystal monochromator unit (using analyzing crystals of germanium (111)) in fluorescent X-ray emission analysis, especially for an X-ray quantometer.
. . ( (111)) , .
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12.
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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13.
, . . , . , , , .
A contribution to the study of electrode spaces of high-current short-duration electric discharges
The electrode spaces of high-current short-duration discharges are analyzed using the method of artificial contraction (limiting of the active surface of the electrodes). It was shown that evaporation of the electrodes during the discharge can be regarded as one of the main factors causing thermal contraction of the channel on the surface of electrodes, high-current density on the electrodes and enabling the independent existence of partial spots.
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14.
15.
The influence of the non-zero value of exchange integrals between Wannier functions, localized in non-neighbouring elementary cells (higher approximation than tight-binding), on the conditions of existence of Tamm surface states and the position of the energy level corresponding to the surface state is shown.
, ( ) , .


This paper is part of M. Tomáek's candidate's thesis.  相似文献   

16.
17.
Zusammenfassung Es werden Versuchsergebnisse des Studiums der Röntgenolumineszenz (RL) von NaCl-Kristallen mit Beimengungen von Elementen der Eisengruppe (Fe, Co, Ni) angeführt. Die Kristalle wurden aus der Lösung und aus der Schmelze gezüchtet. Das Vorkommen und das Höhenverhältnis der einzelnen Emissionsbanden werden diskutiert.
NaCl
NaCl Fe, Co, Ni. . .
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18.
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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19.
We investigate mesoscopic spin transport through a quantum dot (QD) responded by a rotating and an oscillating magnetic fields. The rotating magnetic field rotates with the angular frequency 0 around the z-axis with the tilt angle , while the time-oscillating magnetic field is located in the z-axis with the angular frequency . The spin flip is caused by the rotating magnetic field, and it is the major source of spin current. The Zeeman effect is contributed by the two field components, and it is important as the magnetic fields are strong. The oscillating magnetic field takes significant role due to the spin-photon pumping effect, and the spin current can be generated by it even as 00 for the tilt angle 0. The peak and valley structure appears with respect to the frequency of oscillating field. The generation of spin current is companying with charge current. Spin current displays quite different appearance between the cases in the absence of source-drain bias (eV=0) and in the presence of source-drain bias (eV0). The symmetric spin current disappears to form asymmetric spin current with a negative valley and a positive plateau. The charge current is mainly determined by the source-drain bias, photon absorption, and spin-flip effect. This system can be employed as an ac charge-spin current generator, or ac charge-spin field effect transistor.  相似文献   

20.
The possibility of the polarization of nuclei in paramagnetic salts by saturation of electron paramagnetic resonance is theoretically analyzed. The proposed method assumes saturation of the forbidden transition of the typeM=±1, m=±1, ±2, for mutually perpendicular external magnetic and high-frequency fields. The analysis is carried out for the case of a large quadrupole moment of the nucleus. The degree of orientation attained is comparable in order of magnitude with Overhauser's method. This method is particularly suitable for the polarization of nuclei of transuranium elements.
. M=± 1, m==±1, ±2 . . . .


In conclusion the author would like to thank J. Burget, J. ajko, M. Kolá and M. ott for helping in the laborious solution of system (16).  相似文献   

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