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741.
V. I. Trukhin V. I. Maksimochkin V. A. Zhilyaeva A. A. Shreider T. L. Kashintsev 《Moscow University Physics Bulletin》2007,62(5):296-302
The magnetic and petrochemical properties of basalts dredged from the rift zone at the southern part of the Red Sea at approximately 18° N are studied. The conditions of their formation and evolution are elucidated. The formation of basalts is found to occur in two stages differing in their magma supply rates and redox conditions. Special features of magnetic behavior and the anomalous geomagnetic field in the region were used to determine the sites where the rocks had experienced strong thermodynamic effects (tectonic strain, deformation, heating, etc.). The conditions in which natural remanent magnetization of the basalts was formed are estimated. 相似文献
742.
L. P. Eksperiandova A. I. Fedorov Ya. N. Makarovskaya 《Journal of Analytical Chemistry》2007,62(12):1163-1166
A series of quasi-solid emitters is proposed for the X-ray fluorescence determination of bromine in different bromine-containing compounds. It is shown that sucrose-based glasses are the best emitters for analyzing alkali solutions of halogenated organic compounds, saccharose-based glasses and polymer films are best for analyzing powder samples, and organic gels offer most promise for analyzing liquid (at normal conditions) samples. It is noted that the proposed method can expand the possibilities of commercially produced element analyzers, which are currently intended for determining only C, H, O, N, and S in organic compounds and cannot be used for determining halogens. 相似文献
743.
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747.
We consider a new model for passive mode locking in a semiconductor laser comprising a set of delay differential equations. Bifurcations leading to the appearance and break-up of the mode-locking regime are studied numerically. 相似文献
748.
749.
12 , 169 (1987). Reasonably good agreements in the peak output power and laser efficiency have been achieved. Model calculations
also predict that an efficiency as high as 2.7% can be obtained once the conditions of the above-mentioned experiments have
been optimized. From the consideration that the skin depth effectively limits the absorption length of the microwave pumping
and hence the excitable volume, it is concluded that high input power densities (>2 MW/cm3) and higher gas pressures (between 3 and 10 atm) are the preferable conditions to achieve higher efficiency. Preliminary
calculations on CCl4 containing XeCl gas mixtures show that improvement in laser efficiency by several folds may be achieved as a result of the
higher intrinsic efficiency of excimer formation.
Received: 23 September 1996 / Revised version: 25 March 1997 相似文献
750.
A method was developed for the determination of largest Lyapunov index for short chaotic time sequences with allowance for
the presence of noise in the response of the system. For this purpose a simple unidimensional representation modelling the
dynamics of irregular self-oscillations was investigated. Conditions were found for adequate determination of the largest
Lyapunov index from the noise-distorted signals. The results were used to obtain the largest Lyapunov index for the Belousov—Zhabotinskii
reaction taking place in an ideal-mixing closed reactor and in a constant-mixing flow-type reactor.
Institute of Organic Chemistry, National Academy of Sciences of Ukraine. Translated from Teoreticheskaya i éksperimental’naya
Khimiya, Vol. 33, No. 3, pp. 136–142, May–June, 1997. 相似文献