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The microbiological state of air in buildings of 22 childhood institutions of the Novosibirsk city and Novosibirsk region has been studied. The examined playing rooms were conventionally divided into 3 groups in which the microbial insemination was 1) within normal limits, 2) above normal limits by 2-3 times and 3) above normal limits by more than 3 times. The performed qualitative analysis of the proportion of conditionally pathogenic bacteria and facultative air microflora, and a bacteriological observation of insemination of childrens` nose and throat at kindergartens have demonstrated that the insemination of respiratory pathways correlated with that of the air of rooms. On the basis of qualitative and quantitative analysis of microbial insemination of the air, an assortment of tropical and subtropical plants wawith expressed phytoncide effect was selected. P.249-253

Mechanisms restricting the possibility to increase dispersity of powders produced by mechanical grinding method have been considered. Transformation of nanocrystal powder particles into super-plastic state has been demonstrated to be the main mechanism, whereupon disintegration stops, and all further treatment amounts to change in the shape of particles. Through introduction the notion of macro-dislocation - the linear defect of irregularity in the nanocrystal grain packing - both the process of transformation into super-plastic state and the process of disruption are described. Estimations of disintegration limit for metal powders have been made. Results are in good agreement with experimental data obtained by atomic power microscopy method (APM) on the iron powder ground with surface-active substances (SAS) added. A sketch of formation and development of nanostructure and phase constitution of powder particles being ground in ball mills in liquid organic media has been suggested, which takes account of the process features connected with multiple high-velocity cold-hardening, high temperature polygonization and re-crystallization, and multiple re-chill in liquid media.

An analysis of thermal processes occurring during mechanical treatment (MT) is presented. A two-stage scheme of development of thermal processes in ZnO, ZnO - TiO₂ systems is proposed and their role in the formation of the resulting defect structure is discussed. At the first stage of the MT, the collectivized processes of destruction of individual particles are observed. The second stage of processing is connected with the development of annealing effects caused by heat accumulation processes by the whole sample. The annealing processes favour the formation and accumulation of a set of associates of simple defects that accelerate diffusion processes in components of the mixtures. The processes of accumulation of associates of defects in the sample and a significant rise in the average temperature of the sample are major factors determining the progress of a mechanochemical reaction of the type ZnO + TiO₂

Results of the investigation of mechanochemical reactions of the synthesis of diborane (6) B₂H₆ from M*BH₄ (M* = Li, Na, K) and halides of polyvalent metals MX_n , adducts of BH₃ borane with nitrogen-containing organic Lewis bases (L) of the L ^. BH₃ type, borazine H₃B₃N₃H₃ from M*BH₄ and NH₄Cl, tetrahydroborates of transition metals M(BH₄) _n (M = Zr, Hf, U, Ti) from MX_n and M*BH₄ are generalized. Reactions were performed under mechanical activation of mixtures of crystalline reactants in vacuum ball mills in the absence of solvents. Rotary and vibratory mechanical activators were used. The listed reactions can serve as the basis for mechanochemical technologies. Technological aspects of the application of borane compounds are considered.

The influence of mechanochemical activation (MCA) on physicochemical, adsorption, and catalytic properties of a zeolite in refining low-octane gasoline fraction and aromatization of propane-butane fraction is studied. It is shown that MCA of a zeolite leads to the decrease in its crystallinity degree, specific surface, and acidity. In the composition of the products obtained at the conversion of directly distilled gasoline fractions over activated catalysts the concentration of aromatic hydrocarbons decreases, the content of alkenes, naphthenes and isoalkanes increases, the yield of the desired product enhances. The yield of aromatic hydrocarbons during the conversion of C₃-C₄ saturated hydrocarbons over a zeolite catalyst subjected to mechanical activation for 12 h increases by almost 10 %, its life between regenerations is 1.5-2 times longer.

The paper deals with the effect of mechanical treatment on chitin and chitosan isolated from Gammarus (Amphipoda) of Altay. Water-soluble carboxy-methyl ethers of chitin and chitosan in the solid phase were obtained using mechano-chemical activation in planetary centrifugal mill SPEX 8000. The obtained samples were characterized by means of IR spectroscopy, carboxy-methyl group content was determined, as well as molecular masses, solubility in water, relative viscosity of alkaline solutions.

In the present work, mechanical alloying technique was applied to prepare hard magnetic Sm₂Fe₁₇N_x powders. Starting from pure Fe and Sm powders, the formation process of hard magnetic Sm₂Fe₁₇N_x phase by mechanical alloying and subsequent solid-gas reaction was studied. At as milled condition powders were found to consist of Sm-Fe amorphous and a-Fe phases in all compositions of Sm_xFe_100-x (x = 11, 13, 15, 17). The effects of starting composition on the formation of Sm₂Fe₁₇ intermetallic compound was investigated by heat treatment of mechanically alloyed powders. When Sm content was 15 at. %, heat-treated powders consisted of nearly Sm₂Fe₁₇ single phase. For preparation of hard magnetic Sm₂Fe₁₇N_x powders, additional nitriding treatment was performed under N₂ gas flow at 450

The analysis of some cross effects accompanying solid-phase transformations is performed within the frame of the thermodynamics of irreversible processes. Solid-phase systems capable of chemical transformations belong to complicated thermodynamic systems the state of which, unlike the one thermodynamically equilibrium, can be described by introducing additional thermodynamic parameters. Methods of describing additional parameters may be different depending on specific physicochemical situation and required detailing degree. Many cross effects discussed during thermodynamic analysis are known from experiment even if this is not mentioned. Partial models taking account of different crosse effects are known in continuum mechanics. Examples are presented that illustrate the principal role of interconnections between different phenomena, which is necessary to take into account in mathematical description of solid-phase transformations.

Thermostability of the structure, diffusion permeability and the features of the mechanical properties of nanostructured copper, nickel and composite Cu

Mechanical activation (MA) in high-energy planetary activators is used to prepare disperse and disordered cathode (LiMn₂O₄, LiCoO₂ and Li_1+x V₃O₈) and anode (Li₄Ti₅O₁₂) materials, as well as solid oxide electrolytes (La_0.67-xLi_3xTiO₃) for rechargeable lithium accumulators. The effect of various factors including mechanical and structural properties of initial reagents, oxidation degree of transition metal ions, etc., on mechano-chemical synthesis is investigated. The features of the crystal and electronic structure of the synthesized compounds are studied using different methods in comparison with the materials obtained by the traditional ceramic method.