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101.
The magnetostriction constant of three iron-nickel alloys and one Fe-Ni-Co alloy was measured as a function of the plastic elongation up to about 25%. The magnetostriction constant decreases with deformation in all materials. In Fe-Ni-Co alloy the volume magnetostriction also decreases. The influence of crystallographic texture is discussed and it is shown that it is not a decisive factor. The observed decrease is explained by assuming the influence of lattice deformation on spin-orbital interaction.
In conclusion the authors thank Z. Málek and S. Libovický for carefully reading this paper and for remarks, J. Míová for help in the measurements, J. Cáslavský for X-ray determination of the texture and members of the chemical department of the Institute of Physics for thermal treatment and analysis of the samples. 相似文献
-
- Fe-Ni-Co 25%. . Fe-Ni-Co . , . .
In conclusion the authors thank Z. Málek and S. Libovický for carefully reading this paper and for remarks, J. Míová for help in the measurements, J. Cáslavský for X-ray determination of the texture and members of the chemical department of the Institute of Physics for thermal treatment and analysis of the samples. 相似文献
102.
103.
Miroslav Voříšek 《Czechoslovak Journal of Physics》1955,5(1):89-90
104.
, - 17,6 , . , (8±4)·10–23, (7±4)·10–23 (4±2)·10–23
2. , - . 相似文献
105.
The object of this paper has been to determine the effect of water of crystallization on magnetic properties of MgSO4. Changes in the magnetic properties of MgSO4 in depenedence on the number of waters of crystallization have been established from the magnetic susceptibility changes. The value obtained by measurement differs from that calculated by the additivity law. This disagreement can be explained by the presence of the thermally independent Van Vleck's polarization paramagnetism
p
.The paper brings forward calculations of p values for the individual hydrates of MgSO4.i H2O fori=0, 1, ..., 7. Besides, it examines what portion of the polarization paramagnetism
pi
of the overall values of
pci is due to the effect of water of crystallization. On the basis of this information the deviation from the spherical symmetry, caused by hydration of the MgSO4 molecule, has been interpreted. 相似文献
106.
Strictly localized or resonance Shockley surface states have been found on the (111), (010) and (110) faces of paramagnetic bcc iron for
,¯M and ¯N points in the corresponding surface Brillouin zones. Energy, character of wave function and its damping for these states are reported. Emphasis is laid on implications of surface states in photoemission, field-electron and -ion emission, electron energy-loss or disappearance potential spectroscopy, Auger electron spectroscopy, work function, magnetic properties, electric conductivity, as well as chemisorption and catalysis. 相似文献
107.
Analysing the general dispersion relation numerically, the unstable regions of the relativistic electron-beam plasma system were determined. The external parameters were varied to ensure more effective instability excitations. The full charge and current compensation presumptions lead to new synchronism predictions. The return current's slow space charge wave and return current's slow cyclotron wave are synchronous with the plasma ion wave. 相似文献
108.
V. Čápek 《Czechoslovak Journal of Physics》1978,28(9):995-1002
The thermoelectric power in the Anderson model of electrons in localized states in the mobility gap of semiconducting glasses interacting by attractive forces is calculated at low temperatures. Under some conditions, a transition from the activated form ofS to S=const at low temperatures is predicted. In connection with the activated character of the conductivity, it well corresponds to the experiment on some chalcogenide glasses.The author would like to thank ing. V.Cháb for communicating him the experimental data on As2Te3TIx prior to publication. 相似文献
109.
110.
J. Lašek 《Czechoslovak Journal of Physics》1976,26(2):189-198
Under the condition of nearly equilibrium concentration of vacancies, time dependence of the amount of isothermal transformation given byy=R/R
f was investigated whereR
f is the total structural change of resistivity on completion of the whole process andR is the measured resistivity change. The investigation was done on the 21·8 at.% (40·3wt.%) Zn alloy under the condition of relatively low supersaturation of a few degrees centigrade below the metastable
R
solvus line. The total transformation involves four kinetic stages: the first two stages correspond probably to diffusion-controlled growth of the
R
particles from the supersaturated solid solution and to the ripening of these particles till their conversion to the cubic phase takes place. The last two kinetic stages account analogously for the particles growth and ripening. Both
R
and phases were identified by the transmission electron microscopy. When separating the individual stages, the approximation byy=1–exp [–(mt)
n] of the amount of transformationy was used. The approximation allowed to get the starting values of both the time and the change of the structural part of the electrical resistance for individual stages and also to derive the parametersm
i, ni which had to be redetermined for the individual separated stages. These data made it possible to synthetize the experimental curves ofR andy vs. time for the total transformation.It is a pleasure to thank Doc. Dr. V.Syneek CSc. for stimulating the author's interest in this problem and for providing helpful discussions. I also would like to express my thanks to Ing. P.Bartuka CSc. for the transmission electron microscopic study carried out to identify the particular phases. The author is indebted to Ing.V. íma for the preparation of the investigated alloy and to Mrs. A.Mendlová and Mr. P.Vyhlídka for technical assistance. 相似文献