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11.
Elizarova G. L. Odegova G. V. Matvienko L. G. Talsi E. P. Kolomiichuk V. N. Parmon V. N. 《Kinetics and Catalysis》2003,44(2):211-220
In the interaction with H2O2 in an alkaline medium, Cu(OH)2 forms terminal Cu–OOH and bridging peroxo complexes with the -1,1 and -2:2 structures. It was found that the terminal peroxide is active in the reactions of H2O2 decomposition, diphenol oxidation, and nitrile conversion into acid amides. The promoting effect of ammonia on these reactions was found. A possible mechanism is discussed. 相似文献
12.
Popov A. F. Simanenko Yu. S. Karpichev E. A. Matveev A. A. Matvienko V. N. Prokop'eva T. M. 《Theoretical and Experimental Chemistry》2001,37(6):343-349
An anomalously large increase was found in the rate of cleavage of 4-nitrophenyl 4-toluenesulfonate (13000 times) and diethylphosphate (550 times) by the zwitterionic micelles of 1-cetyl-3-(2-hydroxyiminopropyl)imidazolium chloride and bromide. Detailed kinetic and thermodynamic analysis of these processes made it possible to establish that the main factor responsible for the high rates of reaction in the micellar phase is the concentration of the reagents. 相似文献
13.
Vitalii S. Tkach Dmitrii S. Suslov Gennadii V. Ratovskii Tuczek Felix 《Journal of organometallic chemistry》2008,693(12):2069-2073
A series of palladium complexes of general formula [(Acac)PdL1L2]+A−, where L1, L2 = phosphines and A = BF4, CF3SO3, were synthesized. Preliminary studies show that the complexes are active in selective dimerization of styrene and addition polymerization of norbornene. 相似文献
14.
The problem of supersonic swirling flow past a blunt body is studied numerically on the basis of the complete Navier-Stokes equations.St. Petersburg. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 6, pp. 158–160, November–December, 1994. 相似文献
15.
The need for high quality crystals constantly rise. It is especially obvious in connection with the evolution of electronics and optoelectronics. At the present time all the basic methods for crystal growing are known. So the question arises – what further developments are needed to create further advances? Without doubt first of all it is necessary to speak about perfecting crystal growing equipment. Perfecting modern equipment will enhance and accommodate the results of our understanding of the crystallization physics and provide solutions to the various physical tasks at the atomic and macroscopic levels. Each new step in the process of perfecting the technology and production processes demands large intellectual and material inputs. The continual updating of pullers requires constructive solutions and control systems. Mathematical modelling of the methods of crystallization enables one to more rapidly create the software for the digital systems which are a feature of the latest achievements of physics, that is IT engineering and the modern theory of automatic control.Here we consider the problem of mathematical modelling of crystallization processes from the melt by Czochralski, Liquid Encapsulated Czochralski and Floating Zone methods based on linearization of three conservation laws: the heat, mass and the growth angle constancy is reviewed in depth. Special attention is given to the problem of the dynamical analysis of these processes in open and closed states and to the synthesis of the digital control of crystal diameter for the weight technique. The main problems discussed involve the determination of the parameters required for calculating such control systems together with the use of the multichannel parametric PID regulator involving the state variable observer concept. In addition briefly considered are the problems of digital filtering of the measurement noise based on multidimentional Kalman filters and the determination of mechanical stability limits for static menisci. 相似文献
16.
A. N. Simonov L. G. Matvienko O. P. Pestunova V. N. Parmon N. A. Komandrova V. A. Denisenko V. E. Vas’kovskii 《Kinetics and Catalysis》2007,48(4):550-555
The aldol condensation of formaldehyde and the lower carbohydrate dihydroxyacetone in a neutral aqueous medium is effectively catalyzed by solid compounds (hydroxylapatite and calcium phosphate and carbonate), natural minerals (apatite and vivianite), and soluble phosphates. In excess formaldehyde, the decrease in the concentration of the lower carbohydrate is described by a first-order rate law with respect to dihydroxyacetone. The major products of the reaction between formaldehyde and dihydroxyacetone in the presence of the above catalysts are erythrulose (45–50% selectivity) and 3-pentulose (35–40% selectivity). Branched pentulose and hexulose are also identified among the reaction products. 相似文献
17.
O. V. Matvienko 《Journal of Applied Mechanics and Technical Physics》1995,36(2):151-154
Scientific Research Institute of Applied Mathematics and Mechanics, 634050 Tomsk. Translated from Prikladnaya Mekhanika i
Tekhnicheskaya Fizika, No. 2, pp. 3–7, March–April, 1995 相似文献
18.
19.
Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 5, pp. 113–116, September–October, 1989. 相似文献
20.