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61.
Conclusions The insertion of an additional accelerating system with multiplicity nq is desirable only in a synchrotron with a well-bunched beam, where the natural nonlinearity A
0
2
is small.When the amplitude of the additional voltage is limited by the quantity nVn/Vo1, there are two approximately equivalent schemes for switching on the harmonics nq (see Secs. 3 and 4), which permit obtaining an instability suppression factor of max10/A
o
2
with nopt5/Ao.The efficiency of both schemes has been confirmed experimentally in ISR storage rings [1, 5], but there are no data for making quantitative comparisons of the experimental results with our calculations. At the same time switching on the harmonic n=2 in the PSB synchrotron without satisfying the condition (39) only increased the longitudinal instability of the beam [6].By raising significantly the amplitude of the additional voltage in the state of Sec. 3, which is equivalent to transferring to an acceleration multiplicity nq while keeping constant the number of bunches, it is possible to raise the instability suppression factor to max 5/A
o
2
with nopt2.3/Ao[nVn/Vo]1/4.Translated from Atomnaya Énergiya, Vol. 62, No. 2, pp. 98–104, February, 1987. 相似文献
62.
V. V. Goncharov K. P. Dubrovin E. G. Ivanov V. T. Korneev A. B. Kruglov L. M. Lebedev 《Atomic Energy》1987,62(5):356-363
Conclusions In an MR reactor performance tests of 16 fuel assemblies, with elements having essentially the same structure as standard VVÉR-100 fuel elements, were carried out. Tests of five more fuel assemblies are continuing. Of the 16 assemblies, 13 were studied in a hot laboratory.The tests in the MR, carried out at high loads and with a large number of transition processes, as well as the postreactor studies, indicated that fuel elements of the specified design (with initial helium pressures of 1.96–2.45 MPa) have a high reliability. None of the elements of the fuel assemblies studied malfunctioned due to design defects or faults in their fabrication. During the tests the jackets were subject to a little oxidation and hydrogenation (zirconium-oxide film<3 m thick, hydrogen content less than 0.008% by mass), and their plasticity remained high (the relative elongation at the working temperature remained at the 20% level).Translated from Atomnaya Énergiya, Vol. 62, No. 5, pp. 312–317, May, 1987. 相似文献
63.
Yu. P. Ivanov A. V. Ognev L. A. Chebotkevich 《The Physics of Metals and Metallography》2006,101(5):450-455
The magnetic anisotropy of Co/Cu/Co films with the thickness of the copper spacer corresponding to the antiferromagnetic and ferromagnetic indirect exchange coupling between Co layers has been studied. The films deposited on naturally oxidized (111) Si single crystals were produced by magnetron sputtering. The films were annealed at 240°C. Such an annealing virtually neither changes the grain size nor leads to the mixing of layers; i.e., no disturbance of the coupling type between the cobalt layers takes place. Changes in the surface and induced magnetic anisotropy and in the effective energy of indirect exchange coupling have been studied upon annealing in the presence and absence of a magnetic field. It has been found that the shape of surface inhomogeneities in the films changes upon annealing in the magnetic field applied along the film plane, which substantially affects, the surface anisotropy. In the films characterized by antiferromagnetic coupling, the easy axis of magnetization is induced only in the magnetic fields exceeding the saturation field. The induced-anisotropy constant estimated theoretically agrees well with those determined experimentally. 相似文献
64.
65.
G. Petkova E. Sokolova S. Raicheva P. Ivanov 《Journal of Applied Electrochemistry》1998,28(10):1067-1071
The inhibition effect of gamma-pyrodiphenone (PD) on copper corrosion in near neutral sulphate solutions was investigated. Weight loss and polarization measurements show a high inhibition efficiency (>96%) of PD on copper corrosion at extremely low concentrations. PD suppresses active copper dissolution and oxygen reduction. The potentiodynamic cathodic reduction measurements showed an inhibition of oxide formation and stabilization of the Cu2O oxide in the presence of PD. XPS measurements suggested that the high inhibition effect of PD on copper corrosion is due to the adsorption of PD molecules, as a first stage, and the formation of a film with a polymer-like structure by coordination of PD with Cu2O on prolonged exposure. 相似文献
66.
L. C. Feng W. Z. Shao L. Zhen N. Xie V. V. Ivanov 《International Journal of Applied Ceramic Technology》2007,4(5):453-462
Cu2 O/ x Cu ( x =0–25 wt%) cermets were evaluated as a novel partially inert anode for aluminum (Al) production. The physical and mechanical properties, including the compressive strength, flexural strength, thermal expansion coefficient, thermal conductivity, and dc electrical conductivity were tested at room temperature and at temperatures up to 950°C. The coefficient of thermal expansion, compressive strength, flexural strength, thermal conductivity, and electrical conductivity of Cu2 O/Cu cermets increased with increasing Cu content. High-temperature electrical conductivity measurements showed that with increasing temperature, the electrical conductivity increased when the Cu content was below the percolation threshold, while it decreased when the Cu content was above the percolation threshold. A relatively stable CuAlO2 layer formed on the cermet surface during electrochemical testing, and the corrosion rate of this anode was estimated to be about 1.8–1.9 cm/year in Al production. 相似文献
67.
68.
The values of the elongation at break of filaments in a complex fibre are found by the method of combining the stress-strain diagrams and acoustic emission spectra of fracture of complex fibres. Experimental data are used to assess the correspondence of the empirical law of distribution of the elongation at break of filaments to the theoretical (normal) law. The behavior of filaments in extension of a complex fibre to breaking is described with the concepts of reliability theory and the statistical indexes characterizing the nonuniformity of the filaments and the working capacity of a complex fibre in elongation close to the elongation at break are calculated. Complex fibres fabricated by melt spinning (polyester, polypropylene) have higher reliability reserves than fibres wet-spun from solution (viscose). The results are of practical importance and can be used for optimizing industrial manufacture and processing of complex fibres. 相似文献
69.
V. A. Ogorodnikov A. G. Ivanov E. S. Tyun'kin V. A. Grigor'ev A. A. Khokhlov 《Combustion, Explosion, and Shock Waves》1992,28(1):88-92
Arzamas. Translated from Fizika Goreniya i Vzryva, Vol. 28, No. 1, pp. 94–98, January–February, 1992. 相似文献
70.
V. A. Ogorodnikov A. G. Ivanov V. I. Luchinin A. A. Khokhlov A. P. Tsoi 《Combustion, Explosion, and Shock Waves》1993,29(6):750-754
Experimental results on the spall strength of copper in which the scale of the system was changed by a factor of ten show
that the scale effect for high-rate one-dimensional strain depends on energy. The spall energy per unit surface area for failure
increases with time.
Arzamas-16. Translated from Fizika Goreniya i Vzryva, Vol. 29, No. 6, pp. 88–93, November–December, 1993. 相似文献