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991.
992.
V. A. Tsykanov A. A. Maershin A. A. Petukhov O. V. Skiba P. T. Porodnov G. I. Gadzhiev I. S. Golubenko E. P. Klochkov A. A. Teikovtsev V. K. Shamardin 《Atomic Energy》1989,66(5):329-333
Translated from Atomnaya Énergiya, Vol. 66, No. 5, pp. 299–302, May 1989. 相似文献
993.
Taganrog Metallurgical Plant. Translated form Metallurg, No. 11, p. 34, November, 1989. 相似文献
994.
995.
V. Ya. Malikov P. E. Stadnik O. Ts. Sidletskiy L. N. Lisetskiy S. V. Budakovskiy N. Z. Galunov 《Instruments and Experimental Techniques》2002,45(4):576-578
The device developed allows one to measure the dielectric characteristics of solid substances and their melts at frequencies of 20–20000 Hz and in a wide temperature range of 20–250°C. The measured temperature dependencies of the dielectric permittivities of several molecular and liquid crystals (stilbene, diphenyl, naphthalene, cholesterylpelargonate, and 8OCB) are presented. 相似文献
996.
The possibility of long-term safe disposal of radioactive wastes based on their radiation and radiation-migration balance with the initial fuel component and taking account of the thermal, radiation, and elastic loads due to waste dispoasl on the natural medium is examined. The specific radiation and radiation-migration equivalence is established on the basis of the radiotoxicity of uranium and the components of the decay of uranium and individual radionuclides as well as the sum of the latter. 相似文献
997.
Ferrari A. Ghislotti G. Balsamo S. Spano V. Trezzi F. 《Lightwave Technology, Journal of》2002,20(3):515-518
The behavior of fiber Bragg grating (FBG)-stabilized 980-nm pump lasers is experimentally and theoretically investigated. The subkilohertz noise in the emitted power is related to the coexistence and oscillation between coherence collapsed state and narrow linewidth single-mode (SM) operation. These findings are theoretically discussed by using a multimode time-domain model that accounts for spatial harmonics and includes nonlinear gain. One additional result is an indication that kinks in the L-I curve can be explained by nonlinear mode competition 相似文献
998.
Nuclear magnetic resonance (n.m.r.) studies of 19F nuclei in a random copolymer of vinylidene fluoride and trifluoroethylene were performed at 9.14 MHz and 20.0 MHz. The free induction decays (FIDs) were analysed in terms of two T2 components attributed to the amorphous and crystalline portions of the polymer. The changes in crystallinity as well as the effects of the ferroelectric transition were observed during cycles of heating and cooling between 20°C and 140°C. The crystalline component of the FID lengthens by a factor of 2 at 100°C on heating and decreases by this factor at 60°C on cooling, thus exhibiting the thermal hysteresis of this ferroelectric transition. The spin-lattice relaxation was also investigated. From measurements at 9.14 MHz the observed longitudinal relaxation time T1 appears to be dominated by the dynamics of the amorphous phase and exhibits no anomaly through the phase transition. However, from measurements at 20 MHz, well defined minima of T1 were observed, which are associated with the ferroelectric transition (especially after repeated annealing of the samples). Results are discussed in terms of the crystalline phase structure, which appears dynamically disordered above the ferroelectric phase transition. An analogy is considered with the plastic phase transitions encountered in molecular crystals. 相似文献
999.
A stability criterion is developed for linear, asynchronous multirate sampled-data systems. Such systems typically include a linear, time variant, continuous-time plant and several unsynchronized digital controllers. The analysis method uses a time-domain approach based on the closed-loop state transition matrix. The result is sufficient stability criterion which gives an objective measure of long-term and short-term stability. A simple example illustrates the method 相似文献
1000.