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921.
922.
The temperature disorder of copper ions in the CuCrS2 superionic conductor was studied by X-ray analysis. It is shown that the average square deviations of atoms sharply increase
and become comparable with the distance between neighbouring tetrahedral sites when CuCrS2 transforms into the superionic phase. It is also established that the direction of maximum deviation of atoms is close to
the direction connecting the tetrahedral positions. 相似文献
923.
I. S. Dubenko I. V. Golosovsky E. Gratz R. Z. Levitin A. S. Markosyan I. Mirebeau S. V. Sharygin 《Journal of magnetism and magnetic materials》1995,150(3):304-310
The present neutron diffraction studies have confirmed that TmCo2 represents an exception within the RCo2 series. It was found that, in contrast with other heavy RCo2 compounds, the Co sublattice in TmCo2 does not order magnetically below the Curie temperature (Tc = 3.9 K). This is assumed to be due the fact that in TmCo2 the intersublattice (f-d) molecular field is smaller than the critical field necessary to induce magnetic order within the Co sublattice, as is the case in other RCo2 compounds. Furthermore, we show that the magnetic structure and the onset of long-range order in TmCo2 depend sensitively on the sample preparation, which partly explains the differing results published earlier. 相似文献
924.
Grounds and applications of Bargmann-Michel-Telegdi equations for the precession of the polarization vector of relativistic particles are considered. A critical question in the discussion is the orientation of the rest frame reference vectors. Møller reference frames which keep constant the mutual orientation of the two infinitely close in time rest frames are shown to have a special role. The generally covariant form of the equations is discussed. The assertion that the principle of relativity is violated in the phenomenon of spin precession is proved to be untrue. 相似文献
925.
926.
927.
P. A. Bokhan T. Ya. Dubnishcheva D. E. Zakrevskii Yu. V. Nastaushev 《Journal of Russian Laser Research》1995,16(2):164-171
A gas-discharge gold-vapor laser on self-terminating transitions with operating wavelength λ=312.2 nm has been used to develop a highly efficient system for image transfer. An optical scheme and all its parameters have been chosen optimal for image quality. It has been found both theoretically and experimentally that the best results on micron-structure image transfer are obtained with 2–5-times image reduction. Various types of masks have been used. A 1-µm structure has been resolved due to the choice of optimal exposure time of 10 ms under a period of pulse repetition (0.6 – 0.8) ms; in this case, the minimal fringe dimension was ≈2 µm with an image dimension of 2 mm for a laser tube 1.8 cm in diameter. 相似文献
928.
929.
930.
S. E. Samokhvalov 《Russian Physics Journal》1988,31(12):978-981
For an arbitrary external gauge field we construct an infinite group which contains all the information about the given field and describes some of its properties. We construct a field representation of the group . We show that covariant derivatives become translation generators in such a representation of the group . This allows us to interpret transformations from the group as motions in an external gauge field.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 31–35, December, 1988. 相似文献