Features of formation of cylindrical packs of mineral fibres

The danger of the appearance of fibre segments of increased linear density over the ends of cylindrical packs in winding of mineral fibres was substantiated. Dependences were obtained that allow determining the helix angle of the loops at which the linear density of the fibre will not exceed the acceptable values when the direction of movement changes. __________ Translated from Khimicheskie Volokna, No. 6, pp. 44–45, November–December, 2007.     

Synthesis and characterization of grafted copolymers of aromatic polyimides and ε‐caprolactam

Anionic polymerization of ε‐caprolactam was performed in the presence of only 5 wt % of aromatic polyimides having five‐ and six‐membered imide cycles and bearing hexafluoroisopropylidene, ether, fluorene, siloxane, phthalide, or SO₃H? groups, both in the polymer backbone and as side moieties. The synthesized new copolymers were fully characterized by IR spectroscopy, thermomechanical analysis, dilatometry, and X‐ray diffraction. Tough and frictional properties of the obtained copolymers were estimated as well. It was found that on the selection of polyimide activator it is possible to gain the desirable control over the polymer properties, namely the gel‐fraction content, phase composition, compression modulus, notched Izod impact strength, temperature of frictional contact, friction coefficient, etc. These investigations will facilitate the choice of the optimum macromolecular activator for the modification of both the synthetic method and the properties of the commercial polycaproamide. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Electro-thermo-mechanical coupling in carbon fiber polymer matrix composites

Field coupling in electric-current-carrying composites is studied. Governing equations describing electromagnetic, thermal, and mechanical field interactions in anisotropic materials and a corresponding two-dimensional approximation for transversely isotropic plates are discussed. A problem of electric current?Cinduced heating and the associated thermal stresses in the electrified carbon fiber polymer matrix composite plate is considered. A closed-form solution for the temperature distribution is obtained. It is shown that application of the electric current leads to a significant temperature gradient across the plate. This, in turn, results in a considerable rise of the in-plane compressive stresses in the direction transverse to the direction of the applied current.     

Some aspects of formation of heavy basalt fibre packs

Based on the acceptable deviation of the linear density of fibres, the maximum possible helix angle in the winding body was determined. It was found that the maximum increase in the winding tension is attained in passage of the thread collector. A unit for an additional spring-loaded thread collector which would compensate for fluctuations in the winding tension is proposed. __________ Translated from Khimicheskie Volokna, No. 2, pp. 29–30, March–April, 2006.     

Influence micronization and cooking on changes in inhibitor tripsin of leguminous plants

Legumes are one of the cheapest protein sources. But most of them contains inhibitors tripsin and needs in long processing. Micronization and cooking of legumes only partly destructs the protease inhibitors. The using this products as fast processing food is unwished.     

A computational technique for evaluating the effective thermal conductivity of isotropic porous materials

A computational technique based on Maxwell's methodology is presented for evaluating the effective thermal conductivity of isotropic materials with periodic or random arrangement of spherical pores. The basic idea of the approach is to construct an equivalent sphere in an infinite space whose effects on the temperature at distant points are the same as those of a finite cluster of spherical pores arranged in a pattern representative of the material in question. The thermal properties of the equivalent sphere then define the effective thermal properties of the material. This procedure is based on a semi-analytical solution of a problem of an infinite space containing a cluster of non-overlapping spherical pores under prescribed temperature gradient at infinity. The method works equally well for periodic and random arrays of spherical pores.     

Isolation and Characterization of Two Novel Siphoviruses Novomoskovsk and Bolokhovo,Encoding Polysaccharide Depolymerases Active against Bacillus pumilus

This study describes two novel bacteriophages infecting members of the Bacillus pumilus group. Even though members of the group are not recognized as pathogenic, several strains belonging to the group have been reported to cause infectious diseases in plants, animals and humans. Bacillus pumilus group species are highly resistant to ultraviolet radiation and capable of forming biofilms, which complicates their eradication. Bacteriophages Novomoskovsk and Bolokhovo were isolated from soil samples. Genome sequencing and phylogenetic analysis revealed that the phages represent two new species of the genus Andromedavirus (class Caudoviricetes). The phages remained stable in a wide range of temperatures and pH values. A host range test showed that the phages specifically infect various strains of B. pumilus. The phages form clear plaques surrounded by halos. Both phages Novomoskovsk and Bolokhovo encode proteins with pectin lyase domains—Putative depolymerases. Obtained in a purified recombinant form, the proteins produced lysis zones on the lawn of a B. pumilus strain. This suggests that Novomoskovsk and Bolokhovo may be effective for the eradication of B. pumilus biofilms.