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Abstract New P,S-bidentate phosphoramidite ligands, including these having a stereogenic phosphorus atom in the 1,3,2-dioxaphosphepine ring, have been synthesized on the basis of (Ra)-BINOL and its adamantanyl derivatives. With their participation in the Pd-catalyzed asymmetric allylic alkylation of (E)-1,3-diphenylallyl acetate with dimethyl malonate and the amination with pyrrolidine involving these ligands have afforded selectivity up to 84 and 75% ee, respectively.

The solution to the problem of increasing the motor resource of an internal combustion engine (ICE) is directly related to the reduction of energy losses due to overcoming friction in the elements of systems, mechanisms, and complexly loaded tribo-couplers (TC). Among the mechanical friction losses, a special place isoccupied by the hydromechanical friction losses in the internal combustion engine. The reduction of energy losses to overcome friction is achieved by reducing mechanical losses by limiting the level of loading of the rubbing surfaces, by increasing the proportion of the liquid friction regime for the most critical in terms of reliability resource-determining complex loaded vehicles. For complexly loaded vehicles, the time and magnitude of the acting loads are characteristic, at which the position of the movable element in conjunction is characterized by high eccentricities. Such complexly loaded vehicles include the main and connecting rod bearings of the crankshaft, the “piston guide – cylinder liner” and “piston ring – cylinder liner” couplings, the thrust and thrust bearings of the ICE turbocharger, etc. One of the ways to reduce oil starvation isto texturize the contacting surfaces, which will increase the bearing capacity of a complex bearing due to the creation of many “micro wedges”. In particular, the texturing of the surface of the bearing shells of the crankshaft can be performed in the form of elliptical micro-holes, which allow you to save oil on the friction surface under any operating conditions of the diesel engine. The article provides an overview of the main types of microtexturing of friction surfaces of TC. A calculation model has been created and a calculation analysis program has been developed for the internal combustion engine “crankshaft neck-liner” TC. The calculations ofthe hydromechanical characteristics (HMC) of the vehicle for various types of microtexture were performed using the connecting rod bearing of the diesel engine CHN 13/15 as an example.

Until now, the attention of OMM workers to the treatment of cracked nipples in a woman has not been sufficiently fixed. Meanwhile, this disease, seemingly so insignificant, causing suffering to the mother, often from the very first days disrupts the correct breastfeeding of the child, often forces a woman to transfer the child to early supplementation or even wean it from the breast, which clearly leads to an increase in infant morbidity and mortality.

The paper solved the problem of optimizing the piston skirt profile in the hot state according to the criteria of minimal frictional losses. The authors defined and improved the geometrical parameters of the piston design considering the optimum profile of the skirt; developed recommendations for improving the design of the piston. For six-cylinder V-shaped forced diesel engine, with a cylinder diameter of 150mm and a piston stroke of 160mm (further diesel) a piston design with improved tribological parameters was developed.

The article presents the results of a comprehensive approach to the research and development of technical solutions for the main tribosystems of six-cylinder V-shaped forced diesel engine, with a cylinder diameter of 150mm and a piston stroke of 160mm (further diesel). Technical solutions for diesel are evaluated by solving the problem of dynamics and lubrication of friction units on the basis of a single algorithm for hydrodynamic tribosystems with the reciprocation and rotation movement of the elements with a non-Newtonian fluid

The paper analyzes the numerical model of interaction between the rough surfaces of a piston-cylinder liner tribosystem in the form of a Markov chain. It is based on a model that takes into account elastic and plastic deformation and fatigue failure under load. We have provided a system of equations for the distribution of time-varying heights of protrusions. We have also analyzed the evolution of distributions for the contact interface of the piston-cylinder liner tribosystem of the diesel engine.

The methods and means of improving the operating cycle and design of forced diesel, its fuel efficiency, and the limitation of the thermomechanical loading were considered.

Summary An ion microprobe with high lateral resolution has been used to study the chemical reactions at the fibre/matrix interface of metal–matrix composites. During the squeeze-casting process, the Al–Si–Mg matrix reacts with the preform made of Saffil fibres (96% Al2O3, 4% SiO2). The reaction occurs mainly between the silica binder and Mg from the matrix according to SiO2 + 2Mg = 2MgO + Si. A continuous layer of MgO was formed around the fibres, even on surfaces that were not covered by the silica binder. Possible reasons are discussed for the formation of MgO in areas where binder coating was missing. In such areas, Mg reduces SiO2 that is contained in the fibre. However, the fibres (A12O3) are not attacked by Mg. In the isolated case of fibres that were completely uncoated, no reaction products were observed at the interface. The presence of silica binder seems to be an essential requirement for this reaction to occur. When squeeze-casting is performed with sufficiently high melt temperature, Al from the matrix also reduces silica.

Biological and physical-chemical properties of the pseudotuberculosis agent cultures were shown to be diverse in the process of submerged cultivation at various temperatures. The microbe cultivation at the increased temperature (37°C) was characterized by fast development and death of the population. Decelerated lag phase and extended exponential phase were observed under the conditions of cultivation at low temperature. The culture grown at 27 °C was found to get an intermediate position between those grown at 10 and 37 °C.

Complexation of the chiral P , N -bidentate ferrocene- and cymantrene-based iminoarylphosphites with [Rh(CO) 2 Cl] 2 , [Rh(COD)(THF) 2 ]BF 4 , [Pd(allyl)Cl] 2 , [Pt(allyl)Cl] 4 , [Pd(COD)Cl 2 ] and [Pt(COD)Cl 2 ] was found to give chelate complexes [Rh(CO)(η 2 -P,N)Cl], [Rh(COD)(η 2 -P,N)]BF 4 , [M(allyl)(η 2 -P,N)]BF 4 (M = Pd, Pt) and cis -[M(η 2 -P,N)Cl 2 ] (M = Pd, Pt), correspondingly. With the new P , N -ligands, up to 97% ee was achieved in the asymmetric Pd-catalysed alkylation of 1,3-diphenyl-2-propenyl acetate with dimethyl malonate. In the enantioselective amination of 1,3-diphenyl-2-propenyl acetate with sodium diformylamide, up to 96% enantioselectivity was achieved.

Studies of influence of Yersinia pestis fra-operon carriage on morphological properties of Y. pseudotuberculosis recipient strain cells and colonies at different temperature and cultivation time.Cultures of Y. pseudotuberculosis isogenic variants were grown on solid nutrient medium at 4 - 6, 9 - 11, 26 - 28 and 36 - 38 degrees C. Indirect hemagglutination was used to determine F1 antigen production. Cytorefractometry was used to determine live cell percentage in colonies. Size and dividing cells percentage was evaluated by using phase-contrast microscope "Lyumam-I2".Time period between appearance of micro-colonies and achievement of maximum colony size increased with cultivation temperature decrease. Size of fra+ and fra- variant colony was not significantly different for every temperature regiment used and was significantly lower at the temperature of 36 - 38 degrees C.Temperature has a significant influence on population growth, colony size and form.

The results of the evaluation of the immunogenic properties of B-antigen, earlier identified in the culture fluid of Yersinia pseudotuberculosis submerged culture, with respect to experimental plague and pseudotuberculosis are presented. B-antigen has been shown to produce protective effect in guinea pigs and, probably, hamadryas baboons, but not in white mice infected with the causative agent of plague. Immunizaton with B-antigen protects guinea pigs from primary pneumonic plague caused by both capsule-forming and noncapsular Y. pestis virulent strains. Passive immunization with antibodies to B-antigen induces limitedly pronounced protective effect in guinea pigs and is not effective for white mice with respect to experimental plague. No active or passive protection of white mice or guinea pigs, infected with Y. pseudotuberculosis cultures, has been achieved by the injection of B-antigen or antibodies to it.

Effect of inoculation with canine distemper virus (CDV) strains of various virulence or vaccination with commercial polyvalent preparations on the immune status of puppies has been studied. Serum interferon concentration did not change, irrespective of the strain appurtenance of CDV, while the concentration of tumor necrosis factor-alpha decreased on days 4-14 after the virus inoculation. According to the lymphocyte stimulation test (LST), virulent strain Snyder Hill and reactogenic variant U were characterized by a pronounced immunosuppressive effect. Vaccine strain VNiiViM-88 exerted a stimulating effect in LST. Vanguard 5/L vaccine suppressed the immunity for up to 2 weeks. Vacchum, VNiiViM, and experimental vaccine manufactured by a joint-stock company Vetzverotsentr+ activated the mitogen-induced lymphocyte blastogenesis.