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2.
E. Z. Vintaikin V. A. Udovenko S. Yu. Makushev D. F. Litvin 《Russian Physics Journal》1987,30(3):261-265
The method of neutron diffraction is used to construct temperature dependences of the intensity of 110 antiferromagnetic reflection under the influence of compressive stresses = 0–150 MPa along [001]. Application of the stresses leads to an increase in the transition temperature, the transition being delayed in proportion to the increase in the load. On the other hand, the loading leads to a reduction in the magnetization jump for the antiferromagnetic sublattices. Thus, at > 100 MPa, the antiferromagnetic transformation takes on features of a second-order phase transformation. The transition which takes place in the stressed state is characterized by smoother rearrangment of short-order antiferromagnetic order into long-range order, as is evidenced by erosion of the transition boundary. The model proposed here — which does not ascribe the usual effect to uniaxial stresses on the antiferromagnetic transition in -Mn alloys — is based on the anomalous temperature dependence of the elastic constants.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 92–97, March, 1987. 相似文献
3.
E. Z. Vintaikin V. A. Udovenko D. F. Litvin S. Yu. Makushev V. B. Dmitriev 《Russian Physics Journal》1985,28(5):416-426
Conclusion Thus, the crystallography and the character of antiferromagnetic transformations in manganese alloys determine several specific features of the manifestation of the shape memory effect in these materials. Among these features are: clearer manifestation of reversible deformation, even in the case of small initial strains; a broad temperature range associated with deformation; the practically hysteresis-free character of the reversible deformation in polycrystalline materials; the existence of alternating reversible deformation.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 104–117, May, 1985. 相似文献
4.
Abstract —Our recent research on photochemiluminescence (PCL) of pigments in solutions is reviewed. PCL was observed in the course of photooxidation by oxygen of chlorophyll a , bacteriochlorophyll, protochlorophyll, their analogs, synthetic dyes and aromatic hydrocarbons. The PCL of chlorophyll was studied in detail. It depends on oxygen concentration, intensity of exciting light, pH, nature of pigments, solvents etc. The thermochemiluminescence was observed after illumination of liquid and solid pigment solutions at low temperature (down to - 170C). The excitation spectra of PCL coincide with the pigment absorption spectra. The PCL emission spectra in most cases differ from those of pigment fluorescence. Electron acceptors, electron donors, radical inhibitors and β-carotene quench PCL. The quenching efficiency of electron acceptors is similar to their action on the chlorophyll triplet state. The quenching effect of radical inhibitors and β-carotene correlates with their activity in reaction with singlet oxygen. The effect of quenchers on the chlorophyll fluorescence, photobleaching and pigment sensitized oxygenation was studied. Analysis of experimental data allowed the assumption that chemiluminescence accompanies the decomposition of labile pigment peroxides. The accumulation of peroxides is probably due to the reaction in the complex of pigment and singlet oxygen, formed as a result of energy transfer from photoexcited (triplet) pigment molecules to oxygen. The terminal chemiluminescence emission proceeds from the singlet excited states of molecules of pigments and products of their oxidation. 相似文献
5.
A. A. Dadykin A. G. Naumovets Yu. N. Kozyrev M. Yu. Rubezhanska P. M. Lytvyn Yu. M. Litvin 《Progress in Surface Science》2003,74(1-8):305-318
Monolayer and multilayer Ge nanocluster structures were prepared on Si(1 0 0) using molecular beam epitaxy. The cluster size was 10 nm and cluster density was 1010 cm−2. A stable field electron emission was obtained from these structures, showing current peaks in the current–voltage characteristics, which may be attributed to the resonant electron tunneling via the energy levels of the nanocluster potential well. For cluster multilayers, the current–voltage curves also showed current peaks with a complex shape. The cluster multilayer structures had a considerable temperature sensitivity, as well as photosensitivity, in the wavelength range from 0.4 to 10 μm. 相似文献
6.
P. A. Maksimyuk S. E. Litvin V. Navrátil M. Hamerský 《Czechoslovak Journal of Physics》1979,29(8):924-927
Internal friction measurements were used for the examination of Cd + Zn alloy single crystals. It was established that the interaction energy between solute Zn atoms and dislocations in basal planes is 0·12 eV.The authors thank Dr. P.Luká, CSc., for valuable discussions. 相似文献
7.
V.S. Litvin V. A. Trunov A. P. Bulkin V. A. Ul’yanov V. A. Solovei M. R. Kolkhidashvili S. I. Kalinin R. A. Sadykov E. A. Koptelov 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2010,4(6):873-878
The Gorizont time-of-flight neutron reflectometer—small-angle spectrometer has been designed, manufactured, and assembled to operate with the IN-0 6 pulsed neutron source. The instrument has a vertical neutron scattering plane enabling research on liquid surfaces and interfaces. Model calculations of neutron spectra, beam profiles, and spectrometer resolutions have been performed via the Monte Carlo method. The spectrometer operates at wavelengths from 1.5 to 9 Å and ensures measurements in the momentum-transfer range of 0.003—1.5 Å-1. 相似文献
8.
V. S. Litvin A. D. Belyaev S. M. Ignatov V. G. Nedorezov R. A. Sadykov A. A. Alekseev E. V. Kuznetsova V. L. Kuznetsov V. N. Marin V. I. Ivanov 《Bulletin of the Russian Academy of Sciences: Physics》2009,73(2):219-221
ZnS(Ag)/6LiF and LiI(Eu) scintillators for thermal neutron detectors have been investigated and neutron detectors based on these scintillators and photomultipliers have been tested. The efficiencies of these detectors are 5 and 66%, respectively. The possibility of developing position-sensitive detectors of thermal neutrons with high space and time resolution is discussed. 相似文献
9.
M. V. Litvin 《Radiophysics and Quantum Electronics》2009,52(10):750-757
In this paper, the Shannon theorem is formulated for a discrete noisy channel in terms used in the Shannon formulation. Proof
of the theorem is based on the theory of optimal signals reception, in which the signal intensity with respect to noise has
a significant meaning. Although the formulation contains the notions of the channel capacity and the message-source entropy,
it substantially differs from the Shannon formulation. The obtained formulation allows us to explain some cases where the
information transmission conditions do not satisfy the Shannon theorem. 相似文献
10.
L. V. Sereda Ya. Yu. Aliev I. B. Romanova E. F. Litvin 《Chemistry of Heterocyclic Compounds》1968,4(5):603-605
A method has been elaborated for the quantitative gas-chromatographic analysis of a mixture of piperidine, N-formylpiperidine, and pyridine on polyethylene glycol-4400 applied onto a chromosorb and NaCl, and apezon L, applied onto NaCl. The relative retentive volumes and heats of solution of the components of the mixture were calculated. 相似文献