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Possibilities of using bioclimatic models of zonal classes of Siberian ecosystems for the forecast of forest cover transformations in large-scale changes of climate are considered. For construction of models, the data of the network of meteorological stations  and respective zonal testing grounds were used. As the climate changes, so do their climatic coordinates, which entails a corresponding transformation of the ecosystems.  Based on this assumption is the possibility of a point-by-point prediction of potential states of terrestrial ecosystems  at any preset script of climatic changes. The advantages and limitations of empirical point-by-point models for forecast purposes are discussed.

Investigation was performed of the effect of an external electric field on the completeness of combustion of ASD-1 aluminum powder in an airflow and on the disperse composition of condensed combustion products. It is established that for an oxidizer-to-fuel ratio of 0.8 and a combustor inlet flow rate of 10 m/sec, the application of an electric field increases the completeness of aluminum combustion from 43 to 75%. In this case, the sizes of submicron particles of aluminum oxide practically do not change, and the mass average sizes and the mass concentration of the 4÷50 μm fraction decrease, due to the activating effect of the electric field on the vapor-phase combustion of aluminum particles. A decrease of the mass concentration of the size fraction larger than 50 μm from 12 to 3% under the action of the electric field suppress markedly the agglomeration of aluminum particles during combustion in air.

The paper describes a method for measuring the delay of combustion wave propagation through an obstacle and other heat-transfer parameters by continuous recording of electrical signals arising in a burning condensed system. This method is suitable for systems and obstacles that have marked electric conductivity. Results of investigation of combustion wave propagation through a tantalum obstacle in the 3Zr + 2WO₃ system using the proposed method are presented.
Key words: gas-free system, combustion, mechanical strains, obstacle, combustion e.m.f., heat transfer, thermal parameters.

Some performance of a number of emulsion explosives containing glass micro-baloons were studied experimentally and theoretically. For each of the explosives, detonation velocity was measured and calculated and ballistic mortar tests and cylinder expansion tests were carried out. The results obtained enables a comparison of the usefulness of both testing methods. The influence of some metal nitrates contained in the emulsion matrix on the performance and detonation parameters of the explosives was examined.

An original photograph of a retonation wave is presented; the wave arose spontaneously in a charge of a 20/80 nitroglycerine/ammonium nitrate mixture with a density of 0.9 g/cm³ at a distance of 0.8 of the charge length and went back half of the charge length toward the place of initiation. The velocity of the forward wave was 2300 m/sec, and the velocity of the retonation wave was 1700 m/sec. The retonation wave was registered only in one, unique experiment.
Key words: initiation, detonation, retonation wave, velocity, nitroglycerine, ammonium nitrate.

The microstructure, deformation characteristics, and electric conductivity of composites produced by explosive compaction of a copper–molybdenum powder mixture were studied. It is shown that an increase in detonation velocity during explosive treatment leads to an increase in crystal lattice microstrains and dispersivity of the block structure. This favors the plastic deformation of the particles, mainly copper particles, activation and weldability of their boundaries, which increases the conductivity of the compacts produced. Optimal conditions of explosive compaction and heat treatment for production of composites with high conductivity are found.
Key words: powder mixture, planetary mill, explosive compaction, heat treatment, electric conductivity, x-ray structural analysis.

An explosive method for producing ultrafine α-Al₂O₃ is developed and optimal synthesis parameters are determined. Particles of ultrafine α-Al₂O₃ have a spherical shape and are separated from one another. The size distribution is log-normal (number-averaged size 70 nm and variance 1.9). Special features of phase transitions in ultrafine aluminum oxide under shock-wave action are studied. Results of x-ray phase analysis suggest stabilization of the new high-pressure phase δ'-Al₂O₃ with a face-centered cubic lattice with a parameter a = 8.53 Å.
Key words: metastability, corundum, shock-wave synthesis, surface, modification.

The paper reports results of metallographic studies of specimens of St. 3 steel and M1 copper loaded by shock waves of various intensity (p≈2

The liquid - vapour equilibrium is investigated and phase diagrams liquid - vapour are composed for the systems: HCl - SiCl₄ and HCl - SiHCl₃ within temperature range 203-293 K at total pressure P_total = 1.3 atm. The data obtained can be used to choose conditions of HCl desorption from the solutions HCl with chlorosilanes in order to recover HCl from these mixtures.

The accumulation of chemisorption moisture is found on long storage of technical fluorocarbon materials (FCM) and in the course of slow hydrolysis of CF bonds to form fluoric hydrogen. The features of processes of thermal decomposition of FCMs in vacuum and inert media are studied at 250-700