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51.
It is shown that in the nonlinear electrodynamics of vacuum, which is a corollary of quantum electrodynamics, a weak electromagnetic wave propagates in the field of an intense laser radiation as if this took place in some effective space-time whose metric tensor depends on the electric field of the laser radiation. The components of the metric vector of the effective space-time along the geodesic lines of which the rays of the weak electromagnetic wave propagate in the given case have been found. It is pointed out that this property may serve as a basis for observing the manifestations of the nonlinearity of the electrodynamics of vacuum.  相似文献   
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We findian exact solution of the equations for the model with a laser beam as the source of the gravitational field in the relativistic theory of gravity. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 116, No. 3, pp. 474–480, September, 1998.  相似文献   
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This study investigated the vapor-phase sorption of hydrocarbons (HC) of various chemical nature (n-hexane, iso-octane, benzene, toluene and p-xylene) on zeolite-clay material (ZCM) of Tatarsky-Shatrashansky deposit (Tatarstan, Russia). For comparison, we also studied HC sorption on natural high-grade zeolite (Z) of St. Cloud Mine (New Mexico, USA), two local bentonite clays and synthetic zeolite-molecular sieve Ms5A. As a result, sorption capacity of ZCM towards aliphatic and aromatic HC was significantly higher than the sorption capacity of Z but lower than that of clays. In addition, the data showed that HC sorption on ZCM occurs as surface adsorption. The comparison with Ms5A and erionite ZAPS, a natural Mexican zeolite, revealed that both ZCM and Z do not interact as microporous selective sorbents with linear alkanes. The main differences in HC sorption on ZCM and Z were ZCM higher sorption capacity towards both aliphatic and aromatic HC, as well as its lower sorption sensitivity to the type of HC. We found that the reason for these differences is the presence of large amount of clay minerals in ZCM. To summarize, ZCM can be considered as a suitable adsorbent for protection and remediation of HC-contaminated soils.  相似文献   
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Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 2, pp. 3–7, March–April, 1988.  相似文献   
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The stereoselectivity of the cyclooctene ring-opening polymerization in the presence of the tungsten hexachloride–tetraisobutylalumoxane (TBAO) catalyst system has been studied. The reaction conditions have been established in which the polymer chain isomerization is reduced to a minimum. Under these conditions the stereoselectivity is determined by an individual act of the monomer molecule insertion. The dependence of stereoselectivity on monomer concentration, number of active sites, and temperature has been investigated. The results obtained suggest that the cyclooctene polymerization is selective in favor of the geometrical configuration of the starting cycloolefin (the “retention” effect) by analogy with the previously reported metathesis of acyclic olefins. Considerations which support the idea that cis and trans units are reproduced by the same type of active sites are discussed. The experimental evidence indicates that in this case the stereoselectivity is determined by the difference in kinetics of two reaction paths of the monomer molecule insertion that lead to the formation of cis and trans units.  相似文献   
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