The ecological peculiarities of the testate amoebae population in the Middle Ob flood plain

The biodiversity and distribution of testate amoebae in the Middle Ob flood plain soils have been studied. The biodiversity of Testacea in the soils consists of 83 species and varieties from 12 families. The population of Testacea in flood plain habitats is rich in water forms, especially in the flood plain part of the catena, because of annual floods. The study showed that the density of Testacea in the forest plots is approximately 10 times higher than in the meadow ones. The species diversity of Testacea in the meadows of the flood plain includes 40 species and varieties. It was found that there is an enrichment of the fauna of Testacea in the flood plain meadows with water forms and a decrease in the population of Testacea in the soil according to the depth. The decrease in the diversity and number down the soil profile is related to the decrease in the amount of the oxygen available and general induration of soil. On the whole, the population composition of Testacea in the soils of the pine forest consists of typical representatives of humus substrates with low values of pH, small stock of humus and mineral nutrition. The soils of mature pine forests are rich in Testacea; they have a similar complex of morphological types, mainly because of the moss cover and forest litter thickness.     

Friction in the annular gaps between the control rods and housing of the BREST reactor

Friction and wear between the casing of the control rod and the reactor housing with cyclic rod motion and circulation of high-temperature molten lead in the annular gap.     

Contact friction in lead and lead-bismuth coolants

Analytical and experimental data are presented for the tribological characteristics of contact pairs in heavy-metal liquid coolant.     

Mechanical characterisics of needle-punched materials treated with heated air

A study is made of the relationship between the deformation and strength characteristics of needle-punched materials made from a mix of polyester and bicomponent fibers and treated with heated air. This type of treatment is very effective for obtaining materials with good initial tensile strength. However, the material’s resistance to deformation is preserved with relatively little elongation. Its strength increases only in the transverse direction.     

Mass Transfer of Lead Coolant Vapors in a BREST-OD-300 Reactor

The goal of the work reflected in this paper is to investigate the mass transfer of lead from the coolant surface in the gaseous cavities of the cooling loop of a BREST-OD-300 reactor. The theoretical and experimental investigations show that the amount of lead evaporating from the free surfaces of the first loop of the reactor is negligible.The results of this work are the recommendations that filters should be placed at locations where the pipelines of the gas system, located outside the reactor block, are connected to the reactor cover, because of the possibility of aerosols – dust-like impurities from other sources with mass flow several times greater than the rate of evaporation of lead in the unit – entering the gas system. 2 figures, 7 references.     

Mechanical and structural characteristics of needle-punched materials with the use of different needles

The feasibility of partially or completely replacing imported needles by Russian-made needles is studied. Different needles and combinations of needles were used for the stage in which additional punching is performed. It is shown that Russian-made needles can partially take the place of imported needles, but such a substitution will require closer monitoring of the depth of needle penetration.     

EPR characterisation of carbon black in loose and tight contact with Al2O3 and CeO2 catalysts

The intensity of contact between soot and catalyst is one of the major parameters that determine the soot oxidation reactivity. In the present work the EPR study is focused on the mixtures of carbon black with Al₂O₃ and CeO₂ in loose and tight contacts in order to provide the physicochemical characterisation of the contact. For tight contact CB-catalyst mixtures a new paramagnetic species is observed and can be considered as a fingerprint of the contact between the two solids. These new paramagnetic species increase the catalytic reactivity of CB combustion in the presence of cerium oxide.     

Pore Structure of Heat-Treated Nonwoven Materials

The pore structure of heat-treated nonwoven materials is determined by the conditions of heating and cooling them. The effect of the shrinkage properties of a bicomponent fibre on the pore structure of the materials is manifested at a treatment temperature above the melting point of polypropylene. __________ Translated from Khimicheskie Volokna, No. 3, pp. 41–43, May–June, 2005.     

Modification of composites for production of porous polymeric materials and coatings by incorporation of interpolymer complexes

Systematic studies were conducted and the basic scientific approaches to modification of soluble polymer composites with interpolymer complexes of different composition and structure used for impregnating fibre bases and forming coatings in production of synthetic leathers were designated; different kinds of interpolymer complexes (IPC) were examined and the conditions for obtaining them in different forms were elaborated; methods were developed for hydrophilization of nonwoven fibre bases with interpolymer complexes; the possibility of incorporating lPC in solutions of polyester urethanes (PEU) was demonstrated and the conditions for regulating the pore structure and properties of PEU coatings with them were investigated. The comprehensive approach to modification of synthetic leather as a multilayer composite material and the results obtained are of practical interest and can be used in creating high-quality synthetic leathers for different applications. From a report to the memorial conference dedicated to the 100th birthday of Z. A. Rogovin (Moscow, 2005). __________ Translated from Khimicheskie Volokna, No. 6, pp. 19–22, November–December, 2006.     

Predicting the strength of high-density needle-punched nonwovens

A study is made of the use of a model developed to predict the strength of materials after basic needle-punching and additional needle-punching. With a limit on surface density, the model adequately describes the effect of the structure of the material on its strength in the case of high needle density. The additional needle-punching increases strength in the longitudinal direction without changing the transverse strength achieved during the main needle-punching stage.