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131.
A. V. Ivanov M. Yu. Tsentalovich E. G. Kogan L. G. Tomilova N. S. Zefirov 《Russian Chemical Bulletin》2008,57(8):1676-1679
The chlorination of benzene, toluene, and o-xylene with molecular chlorine in the presence of the phthalocyanine complexes of different structures was studied. The transformations
of the catalysts during the reaction were investigated.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1644–1647, August, 2008. 相似文献
132.
A. Ya. Samuilov L. A. Zenitova I. N. Bakirova Ya. D. Samuilov 《Russian Journal of Applied Chemistry》2008,81(8):1419-1422
Thermodynamic parameters of reactions of methyl and phenyl isocyanates with a series of compounds were determined by quantum-chemical calculations. The products of these reactions model for various functional groups present in commercial polyurethanes. The thermodynamic stability series for compounds formed from aliphatic and aromatic isocyanates were constructed. 相似文献
133.
134.
The results of investigations of the rheological characteristics and electrical resistance of the suspensions of carbon black in vaseline oil under the effects of shear and vibration were presented. The investigations are carried out on an original unit that allowed one to simultaneously subject the suspensions to shear deformation and orthogonal vibration. The electrical resistance was also measured in an ac pulsed low-voltage mode. Possible mechanisms of the suspension conductivity were considered depending on the regime of dynamic action. 相似文献
135.
Feel like writing a review for The Mathematical Intelligencer? You are welcome to submit an unsolicited review of a book of your choice; or, if you would welcome being assigned a book to review, please write us, telling us your expertise and your predilections. 相似文献
136.
Burn‐in is a widely used method to improve the quality of products or systems after they have been produced. In this paper, we consider the problem of determining the optimal burn‐in time and optimal work size maximizing the long‐run average amount of work saved per time unit in the computer applications. Assuming that the underlying lifetime distribution of the computer has an initially decreasing or/and eventually increasing failure rate function, an upper bound for the optimal burn‐in time is derived for each fixed work size and a uniform (with respect to the burn‐in time) upper bound for the optimal work size is also obtained. Furthermore, it is shown that a non‐trivial lower bound for the optimal burn‐in time can be derived if the underlying lifetime distribution has a large initial failure rate. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
137.
138.
Time structure of iodine laser pulse in the free running mode of operation was studied using the power amplifier of laser system PERUN as the laser oscillator. Two characteristic shapes of laser pulse correspond to different regimes of laser operation, the existence of which is ascribed to the critical concentration of I2 molecules. Simultaneously an additional chemical pumping was proved at least in the initial phase of photodissociation and in a late-time lasing after the end of flashlamps pumping light. 相似文献
139.
140.
Summary We have estimated and measured the daily thermal expansion of an oceanographic platform. This has been found negligible as
far as the calibration of a satellite altimeter is concerned. 相似文献