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Prognostic express diagnosis of metabolic dysregulation was tested in highly qualified athletes engaged in various Olympic sports. The method is based on laser correlation spectroscopy (LCS) of biological fluids, which has widely been approved for use in medicine and evaluation of risks for natural and anthropogenic anomalies. Evaluating the risk for metabolic dysregulations with the relevant criteria will help to objectively estimate the efficiency of preventive actions in athletes.

Quantum chemical calculations of the electronic structure of [Ni2(μ-O2CCH3)4(O-DMSO)2] complex were performed using the DFT B3LYP method in the 6-31G(d,p) basis. The calculations made it possible to detect the existence of two types of stable structures of Ni(II) high-spin binuclear carboxylate complexes with different terminal ligands, i.e. with a relatively symmetrical metal-carboxylate Ni2(μ-O2CR)4 framework and with its significant distortion caused by the second-order Jahn-Teller effect.

Currently, nickel(II) carboxylates are widely used as the starting materials for the synthesis of more complex systems [1, 2]. Typically, the synthesis of nickel carboxylates is carried out starting from the nickel hydrated oxide or carbonate and the corresponding carboxylic acid, as well as from the nickel(II) halide and the carboxylic acid salt. Note that these reactions afford fundamentally different complexes, depending on the properties of the substituent R of the carboxylate ligands. Thus, according to [3], reaction of the basic nickel carbonate with pivalic acid (PivH) at heating followed by crystallization from benzene gives a binuclear complex. The binuclear aqua-bridge complex [Ni2(μ-OH2)(μ2-Piv-O,O')2(Piv)2(PivH)4] was obtained by heating (160°C, 3 h) of basic nickel(II) carbonate tetrahydrate with an excess of pivalic acid or by the boiling of nickel(II) hydroxide with PivH in toluene [4, 5]. The reaction of propionic acid with nickel(II) oxide in an autoclave (75°C, 48 h) results in a mixture of a polymer compound containing a binuclear lantern fragments Ni2(μ-O2CEt)4: [Ni2(μ-O2CEt)4]∞ and monomeric complex [Ni2(μ-O2CEt)4(OH2)2] [6].

Studies of the process of drawing 5-tex polyamide textile yarn at take-up speeds up to 1650 m/min have been performed on a laboratory stand.

On PETP filaments with a structure evaluated by IR spectroscopy, X-ray structural analysis, birefringence and measurement of density, the authors have obtained experimental evidence on a link between the functions of orientation of of the macromolecules in unordered and ordered regions of the polymer, the content of the extended fragments of the macrochains and their aggregates and the size of the maximum internal stresses in the isometric heaving curves.

The rearrangement in structure of PET yarn during short heat treatment times, that is, during the warming-up period and in the initial period of yarn heat treatment, has been examined from the evidence of isometric heating, IR spectroscopy, change in birefringence, density, and physicomechanical characteristics of yarn which has been heat treated in an air heating chamber at 200°C. It has been shown that during the time of warming up the yarn, structural changes are determined by relaxation processes. After heating, crystallization processes exert an important effect on the properties of the heat treated yarn. The complex character of the structural rearrangement leads to a nonhomogeneous change in physicomechanical properties of the yarn.

The molecular weight of the polymer, filament diameter, and cooling conditions during spinning exert a considerable effect on the size of the skin and the structural nonuniformity over the cross section of polycaproamide monofilaments. A monofilament with minimum skin dimensions is the most transparent and elastic. At low spinning temperatures and with the use of organic liquids for cooling, it is possible to obtain a monofilament with no skin.

The use of a technological scheme which combines the processes of twisting and yarn heat-treatment makes it possible to intensify the process of textile grade polyester yarn manufacture as a result of shortening the series of textile-technology steps. The scheme permits one not only to set the twist well, but also to regulate the basic physicomechanical properties of the yarns over a wide range. By using the proposed technological scheme, depending on the assigned degree of deformation, one can obtained twisted yarns with a shrinkage of 1–2% at an initial elastic modulus up to 20 MPa.

An effect of drawing temperature on the change in structural-mechanical properties of 111 tex polyester yarns during subsequent heat-treatment has been demonstrated.

height had been left out of account. The height at which the t roughs a r e s i tuated prevented opera t ives of shor t s t a tu re to c o r r e c t the fault. A large number of inf r ingements like "misa l igned auger s" or "miss ing or b roken y a r n guide hooks" were caused main ly by a lack of at tention on the par t of the tending personnel who cons idered these faults to be "of no s igni f icance".

It is well known that during treatment with spinning preparations undrawn Kapron fibre picks up a portion of moisture, which may be more or less, and during heat stretching the moistened fibre is subjected to the action of high temperature. The "cutting in" of the outer layers of the winding into the lower ones which is observed in package drying permits one to suggest the formation of deformation due to the considerable stresses, which may also affect the strains in drawing fibres. In this connection, an estimate of the level of the stresses which arise in undrawn Kapron fibres on removal of moisture presents definite interest.

The skin of a fiber is a significant factor in many of its properties. There are several methods of dyeing the cross-section of Capron fiber for the purpose of differentiating between the core and the skin /1-3/.The fact that Capron fiber consists of a core and skin was discovered by tinting the cross-section of fiber swelling in a zinc chloride solution with iodine /I/. Berry /2/and Kato /3/ dyed fiber sections with I% dye solutions which caused less swelling and were either sorbed selectively by the skin or were washed out of the fiber. In Berry's method the cross-sections are dyed successively with acid and basic dyes which render the s'=in clearly discernible within a short period at a low temperature. In Kato's method only one dye is used. In one variant of this method the whole cross-section is dyed after which a wash renders the skin discernible, while in another only the skin is dyed (Table I). In another method /4,p.327/ use is made of the first variant of the Kato method with metal-containing Dark Brown NKM as the dye. In the second variant of Kato's method the dye is Congo Red /5/

With polymers which can crystallise on being stretched, the relationship between shrinkage and internal stress is conditioned not only by orientation of the macro-molecular chains, but also by the ratio of the amorphous and the crystalline zones.

The internal fibre stresses govern the behaviour of the fibres during processing and in service. It was shown elsewhere /I/ that the magnitude of these stresses in the region of the first peak of the isometric heating (IH) diagram depends not only on the orientation of the macrochains but also on that of the macrostructure of the fibre. In the work reported here the relation was determined between the remaining parameters of the IH diagram, the conditions under which the polyacrylonitrile fibre was produced, and the composition of the copolymer.

A common method of studying fibre behaviour in heating is that based on isometric heating. It is well known /I/ that the stresses developing in the specimen in isometric heating depend on the mean orientation of the macromolecules but for fibres spun from a polymer solution other factors enter. The results of the investigation described here were obtained by isometric heating and are linked with the structure and properties of wet-spun polyacrylonitrile (PAN) fibres.

The change in the structure of a polyacrylonitrile fiber after various stages of processing has been investigated. The existence of three relaxation processes in isometrically heated polyacrylonitrile fibers is demonstrated.