The First Enikolopov's Readings

Abstract

The first Enikolopov Readings were held on March 14, 1994 at the Institute of Synthetic Polymeric Materials (ISPM), Russian Academy of Sciences, Moscow. These Readings were dedicated to the 70th Anniversary of the Birthday of Professor Nickolay S. Enikolopov, who made an oustanding contribution to the development of Chemical Physics, Physical Chemistry, and Chemistry and Physics of Composites. The leaders of the Russian scientific community gathered in order to remember the achievements of this great scientist of the former Soviet Union.     

Information: 1992 Korshak's Readings

The Annual Korshak's Readings were held in the Institute of Elemento-Organic Compounds (IEOC) of the Russian Academy of Sciences (Moscow) on January 9,1992. They were organized by the Russian Academy of Sciences, IEOC, the Scientific Council on Macromolecules of the Division of General and Technical Chemistry of the Russian Academy of Sciences, and the Mendeleev Chemico-Technological Polytechnic (MCTP). About 100 scientists from 15 scientific centers of Russia participated in these Readings.     

International Conference on Regulation of Polymeric Material Stability: A Report

The International Conference on Regulation of Polymeric Material Stability was held on October 12-15, 1992, in Moscow in the Institute of Chemical Physics of the Russian Academy of Sciences, mostly through the efforts of the Division of Chemical and Biological Kinetics of the aforesaid institute.     

Adhesives for assembly on printed-circuit boards

Requirements for adhesives used in the surface-mount technique are presented. Properties of a heat-setting epoxy adhesive TPK-4 designed at the Semenov Institute of Chemical Physics of the Russian Academy of Sciences together with the OOO NPF Tekhpolikom are described.     

International Symposium On Degradation and Stabilization of Polymers: A Report

An international symposium on degradation and stabilization of polymers was convened by the All-Union Center on the Problems of Polymer Aging and Stabilization? set up at the Institute of Chemical Physics, Academy of Sciences of the USSR. The symposium was held October 10-13, 1988, in Moscow, USSR.     

Twenty-Fourth Kargin's Readings

The regular Kargin's Readings were held on January 24, 1994, in the Chemistry Department of Moscow State University. They were the 24th readings, Professor Valentin A. Kargin, the founder of polymer science in our country, the head of the Scientific Council on Macromol-ecules of the USSR Academy of Sciences (1948–1960), and the head of the Chair of Macromolecules of the Moscow State University, having passed away in 1969. Professor Kargin had founded the great school of experts in the area of physics and chemistry of polymers. He was very active in the science and his contribution mainly concerned the structural approach to synthesis, technology, and physical and chemical properties of polymers. Now Russian and foreign colleagues and disciples of Professor Kargin are preparing a memorial book about this outstanding scientist.     

Information: Sixth Korshaks Readings

Traditional Korshak's Readings were as always held January 11–12, 1994, around the birth date of Professor Vasilii V. Korshak, who was a founder of the synthetic polymer school in former Soviet Union and was at the head of polymer science in the USSR for a long time. Among his disciples there are 200 philosophy doctors and 40 doctors of science. This year the Readings were dedicated to the 85th Anniversary of Professor Korshak's birthday (January 9, 1909). They were organized by the Scientific Council on Macromolecules of the Division of Pure and Applied Chemistry of the Russian Academy of Sciences, Nesmeyanov Institute of Elementoorganic Compounds of the Russian Academy of Sciences (IEOC), and Mendeleev Russian University of Chemistry and Technology. The Organizing Committee involved well-known colleagues and disciples of Professor V. V. Korshak. They were Professors A. L. Rusanov (the chairman), A. A. Askadsky, P. M. Valetsky, V. A. Vasnev, S. V. Vinogradova, Ya. S. Vygodsky, V. A. Davankov, V. V. Kireev, and A. R. Khokhlov. About 100 scientists from 15 research centers contributed in the conferences.     

Acceleration of the deflagration-to-detonation transition in gases: From Shchelkin to our days

The development of some Shchelkin’s ideas in investigations of the Semenov Institute of Chemical Physics of the Russian Academy of Sciences is described. These ideas include the discovery of different effects of intense and weak turbulence on surface combustion, study of phenomena near the detonation origination point, experimental demonstration of chemical self-preparation of an explosive mixture, and identification of the dominating role of gas-dynamic factors in the deflagration-to-detonation transition.     

Basic self-ignition regimes and conditions for their realization in combustible gas mixtures

Self-ignition of hydrogen-air mixtures has been studied experimentally. This process was initiated behind a reflected shock wave at an initial pressure of up to0.5 MPa and with hydrogen volume contents ranging from9.5–20 and40–60%. Simultaneous recording of pressure and temperature profiles near the end of a shock tube made it possible to reveal the specific features of various self-ignition regimes and the regions of their existence. The peculiarities of the realization and evolution of mild and strong self-ignition processes are discussed, and a comparison with self-ignition of carbon-air mixtures is done. Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow 117977. Translated from Fizika Goreniya i Vzryva, Vol. 33, No. 2, pp. 3–10, March–April, 1997.     

Simulation of auto-ignition of iso-octane and n-heptane in an internal combustion engine

A detailed kinetic mechanism is proposed for the oxidation of iso-octane, n-heptane, and mixtures of them in air (number of particles 43, number of reactions 284), which satisfactorily describes the distinctive features of low-temperature and high-temperature oxidation at an initial temperature of 1200 K, pressure of 15–40 absolute atmospheres or higher, and a fuel excess ratio of 0.5–2. The abbreviated mechanisms obtained to describe the auto-ignition of fuel with an octane number of 90 involve 27 particles (38 reactions) and 18 particles (22 reactions).N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow, 117977. Translated from Fizika Goreniya i Vzyrva, Vol. 30, No. 6, pp. 15–25, November–December, 1994.     

Biodegradable polymer composites based on synthetic and natural polymers of various classes

The state-of-the-art in the field of polymeric materials that can degrade under environmental conditions into environmentally harmless compounds is reviewed. It is shown that the most efficient method for the production of such materials involves the creation of composites based on synthetic and natural polymers, in particular polysaccharides. Studies performed at the Semenov Institute of Chemical Physics, Russian Academy of Sciences, have demonstrated that biodegradable composites consisting of various polysaccharides with LDPE and polylactide may be obtained by an ecologically pure solid-phase method under the action of high-temperature shear deformation.     

Formation of nitrogen oxides behind the shock front during explosions and electric spark discharges in the atmosphere

Based on Ya. B. Zel'dovich's kinetic model which describes nitrogen oxidation in heated air, we construct a generalized analytical theory for generation and freezing of thermal NO_x. The relations for determining the quantity of nitrogen oxides formed in intense shock waves of various symmetry have been found, and the yield of the thermal NO_x in spherical shock waves excited by powerful explosions in air has been estimated. The pattern of NO_x formation during natural spark discharge in the atmosphere has been constructed for the first time. For this purpose, using the laws of instantaneous cylindrical explosion we model the air cooling behind the shock wave excited by a linear spark discharge.N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 117977 Moscow. Translated from Fizika Goreniya i Vzryva, Vol. 31, No. 1, pp. 112–118, January–February, 1995.     

Influence of catalysts on the combustion of ammonium bichromate

The influence of inorganic and organic catalysts on the combustion of ammonium bichromate has been investigated at pressures ranging from 1 to 1000 atm. The maximum catalytic action of additives has been found to occur at atmospheric pressure, with the combustion rate for the most effective additives decreasing by a factor of four to five. The influence of the same additives on the combustion of other ammonium salts studied earlier is compared. Institute of Chemical Physics, Russian Academy of Sciences, 117977 Moscow. Translated from Fizika Goreniya i Vzyrva, Vol. 31, No. 6, pp. 28–36, November–December, 1995.     

Onset of convective burning in picric acid

Based on simultaneous optical registration and measurement of the pressure at several points along the height of a sample, we have studied the onset of convective burning in picric acid when it is ignited from a closed end. We have investigated the effect of the particle size and density of the explosive (0.7–1.1 g/cm³), the height of the sample, the power of the igniter, and the parameters of the channel in the shell. We have obtained the spatial profiles of the pressure distribution. We have determined the dependence on the investigated parameters of the critical height of the bed at which convective burning begins. We have determined two typical cases realized in the initial stage of development of the process. For one case, a smooth increase in pressure before and after the luminosity front is characteristic; for the other case, the presence of a peaked pressure distribution close to the front is characteristic. We have established the conditions under which a specific case is realized. We suggest an explanation for the results obtained.N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow 117977. Translated from Fizika Goreniya i Vzryva, Vol. 31, No. 1, pp. 26–32, January–February, 1995.     

Equipment for Nuclear Test Sites

This paper describes the equipment designed at the Special Department of the Institute of Chemical Physics (Institute of Earth Physics, presently Institute of Geosphere Dynamics of the Russian Academy of Sciences) and manufactured at the Design Bureau of the institute to record the physical processes accompanying nuclear explosions. Many of from were used as standard equipment at nuclear test sites.     

Heat production kinetics and the scope for thermal self-ignition in wheat drying

Heat production has been examined at various oxygen partial pressures in the oxidation and thermal destruction of grain products by the use of a DAK-1-2 differential microcalorimeter. Estimates have been made on the adiabatic induction periods and critical sizes of the grain product layers on a metal surface (boundary conditions of the first kind) in the absence of heat transfer from the other surface. It is found that thermal self-ignition will occur in degenerate mode when thermal destruction is decisive.Chemical Physics Institute at Chernogolovka, Russian Academy of Sciences 142432 Chernogolovka, Moscow Region. Translated from Fizika Goreniya i Vzryva, Vol. 30, No. 1, pp. 55–60, January–February, 1994.     

Computation of the detonation limits in gaseous hydrogen-containing mixtures

A systematic investigation was undertaken of the possibility to derive a one-dimensional detonation limit theory using the hydrogen-containing mixture as an example. The treatment was based on a detailed hydrogen oxidation scheme. It was shown that the one-dimensional theory satisfactorily predicts the detonation limits as a function of the composition, initial temperature, the pressure, and the inert diluent type and content.N. N. Semenov Chemical Physics Institute, Russian Academy of Science. 117977 Moscow. Translated from Fizika Goreniya Vzryva, Vol. 30, No. 1, pp. 92–100, January–February, 1994.     

Electrical signals in shock compression of the Sn+S system

Experimental data are presented supporting the validity of using the electrical response of a semiconductor to shock compression as a method of studying chemical interactions in heterogeneous systems behind a shock-wave front. The method is tested on theSn+S system at dynamic pressures above 20GPa. Institute of Chemical Physics, Russian Academy of Sciences, Chernogolovka 142432. Translated from Fizika Goreniya i Vzryva, Vol. 33, No. 2, pp. 139–142, March–April, 1997.     

Use of liquid ammonia to increase the quality of textiles made of hydrated cellulose fibres

A method was developed for preparation of samples for determining the adhesive strength of joints of thermoplastics with CF 6–9 µm in diameter by the pull-out method. The proposed method can be used to evaluate the adhesive power of thermostable thermoplastics (polyphenylene sulfide, polycarbonate, polysulfone, polyphenylene sulfide sulfone). The strength of the interface in bonds of these polymers with UKN-5000 fibres in the selected spinning conditions is sufficiently high and is as good as the adhesive strength of bonds of fibres with modified epoxy resins.Institute of Chemical Physics, Russian Academy of Sciences, Moscow; Tekhnologiya ONPP RF GNTs, Obninsk. Translated from Khimicheskie Volokna, No. 4, pp. 33–37, July–August, 1995.     

Effect of nonisentropic processes on transition from combustion to detonation in combustible mixtures

The problem of spontaneous combustion of a compressible reacting gas in a wall boundary layer behind a single shock wave in a tube with an adiabatic wall is examined. The possibility of leading spontaneous combustion of the gas in the boundary layer compared with spontaneous combustion in the flow core is shown in an approximation of a one-stage chemical reaction. Explosion in the boundary layer occurs locally, and in the vicinity of the exploding gas particle there is a finite gradient of the spontaneous-combustion induction time. The calculated velocity of the spontaneous-combustion (spontaneous-flame) wave is close to the local sound velocity, which indicates the possibility of the generation of a strong blast wave. With consideration of the nonadiabatic character of the wall, the investigated effect is manifested as a result of multiple compression of the reacting mixture by shock waves or simple compression waves, as well as for a wall made of a material with a low thermal conductivity.N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow. Translated from Fizika Goreniya i Vzryva, Vol. 31, No. 3, pp. 29–36, May–June, 1995.