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An experimental investigation has been conducted into the pyrolysis of typical medical waste components in a fixed-bed reactor with a view to obtaining detailed information on the process characteristics. It is shown that the main loss of the mass of the mixture of chlorine-containing medical wastes occurs in two stages. The first stage which finishes at a temperature of about 400°C is characterized by the discharge of pyrolysis water and gas which contains hydrogen chlorine. At the second stage, at a temperature from 400 to 500°C, there is a discharge of the main part of volatile substances that are largely made up of pyrolytic oil. An environmentally safe and cost-effective method of solving the problem of medical waste disposal based on its two-stage pyrolysis has been proposed. The method includes the removal of chlorine-containing components from medical waste before the thermal degradation of their organic part, which, in practice, excludes the possibility of formation of highly toxic chlorine-containing substances.

Experimental investigation of the ignition of a stoichiometric hydrogen–oxygen mixture behind an incident shock wave in a shock tube at pressures p = 0.002–0.46 MPa and temperatures T = 500–1000 K is carried out. The existence of three limits of ignition typical of the ignition of hydrogen–oxygen mixtures in a spherical vessel is noted. It is shown that at pressures p ≥ 0.1 MPa the ignition of a hydrogen–oxygen mixture begins at a much lower temperature than the ignition of a hydrogen–air mixture. The measured induction times agree well with theoretical estimates.

The present paper considers the state of the art of investigations on the use of nanomaterials in the technology of preparing proton exchange fuel cells. This technology has great prospects for use in transport facilities, as well as in stationary and portable electronic devices. The unique properties of nanostructures permit creating new effective catalysts, polymer membranes, and hydrogen storage systems — key elements of the above technology, which upgrades markedly the efficiency of energy conversion in devices created on its basis and decreases their cost.

We have made an experimental study of the ignition of a stoichiometric hydrogen–air mixture behind the incident shock wave front in a shock tube. The ignition limits and the induction times of the mixture behind the wave front in the range of temperatures T =550–960 K and pressures P =0.01–1.1 MPa have been determined. Much lower values of the ignition temperature compared to the experimental results obtained in reflected shock waves, as well as to the classical Lewis and Elbe, have been registered. The measured induction times in the above temperature and pressure ranges are in good agreement with theoretical estimates.

This paper considers the problems of hydrogenation of graphene in a hydrogen atmosphere from the kinetic point of view with the use of methods of electron-beam lithography. A kinetic model of the radiation-chemical processes in a gas has been constructed. On the basis of the analysis of the available experimental data, the rate constant of hydrogenation has been determined. The influence of various parameters of the process on its rate has been investigated.

This paper considers the state of the art in the application of radiation technology for obtaining and investigating new functional materials, devices, and systems of nanometer sizes where the key role is played by the quantum properties of the substance. This concerns in the first place the production of ion-track membranes, polymeric nanocomposites and nanogels, three-dimensional nanostructures, finely dispersed powders, semiconductor nanometric structures, carbon nanostructures, microchips of the new generation based on graphene transistors, etc.

Consideration has been given to the current status of research on the use of radiation techniques for synthesizing new carbon nanomaterials based on fullerenes, carbon nanotubes, and graphene sheets and their derivatives, which are promising for practical application due to their unique properties. An analysis has been made of the existing experimental and theoretical works on studying different processes induced by the action of radiation on carbon nanostructures (melting of cross-linking carbon nanotubes and formation of molecular junctions between them, polymerization of fullerene layers, formation of new structures, radiation chemistry of fullerenes, and others).

A theoretical study of the radiation stability of carbon nanostructures irradiated by an electron beam has been made. Calculations have been performed with the use of an analytical expression for the cross-section for scattering of relativistic electrons by carbon atoms, as well as of the data on the threshold energy of atomic displacement from the carbon lattice obtained by the molecular dynamics method. Stability limits of carbon nanostructures and basic parameters of the process have been found. The calculated values of the characteristic time of the process are in good agreement with the available experimental data.

Various formation mechanisms of polycyclic aromatic hydrocarbons and fullerenes in benzene flames have been analyzed. It has been shown that the process of building-up of the aromatic structure of the given components in the flame includes both the addition of acetylene molecules with subsequent intramolecular restructuring and formation of new aromatic rings and coagulation in which fullerenes are assembled from different aromatic fragments. We propose an optimal model of the process providing the best agreement with the available experimental data.

A set of experiments on determination of the parameters of the gas release from a mold have been performed. The thickness of the casting, the thickness of the mold wall, the process time, and the temperature of the charged metal (liquid gray cast iron) were varied. The investigated molding sands were prepared from quartz sand and organic binders: M19-62 (urea resin), FF-1S (furanic resin), and PK-104 (phenolic resin). On the basis of the experimental data obtained the kinetic parameters of the thermal decomposition of the considered resins have been determined.

A mathematical model of gas release from a mold in the stage of solidification and cooling of metal has been constructed. The model includes heat and mass transfer on the mold’s capillary-porous medium containing phenol-formaldehyde resin as a binder; it also includes the kinetics of pyrolysis of the resin and secondary chemical reactions between the products formed. The process has been investigated experimentally. It has been shown that the model gives a fairly good description of the process in a wide range of variation in its parameters within the framework of the assumptions made.

Modern investigations on creation of kinetic models of combustion of hydrocarbons entering into the composition of kerosene and kerosene as a whole have been analyzed. Certain recommendations on application of these models to calculation of actual gasdynamic flows have been given.

The main mechanisms of transformation of mercury compounds in coal combustion products in the region of high temperatures have been analyzed. A kinetic model of the process of gas-phase oxidation of metal mercury vapors is proposed. The features of the behavior of the investigated compounds in systems of cleaning combustion products from harmful impurities have been considered.

The thermodynamic approach to the description of the fuel–oxidizer system is used to elucidate the basic laws of behavior of compounds of the most toxic elements‐microimpurities in combustion products of coal (Hg, Pb, Cr, Mn, Ni, Co, and As). It has been shown that the distribution of elements over components of the gas and condensed phases strongly depends on the process temperature and the composition of the mineral part of the coal.

A thermodynamic approach to description of the behavior of the fuel–oxidizer system in burning coal is employed to reveal the basic regularities of the process of redistribution of the chemical elements of its mineral part among the ash‐forming components. It is shown that the composition of the mineral part is of prime importance in this process.

A mathematical model of pyrolysis of coal particles is developed that takes into account the heat transfer of a particle with the surrounding medium, the kinetics of release of volatile components, the secondary reactions of cracking, and the depositions of tar in its motion in the particle pores. Calculated results are compared to available experimental data.

Results of some studies of formation and transformation of harmful substances during combustion of organic fuels are presented. The studies were conducted within the framework of the program “Environmental Problems of Heat Engineering” of the AVOGADRO system.