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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 article is devoted to the problems of definition, classification and genesis of the Epigravettian in the Central regions of the East European plain. It is concluded that Epigravettian sites could be characterized as industrially variable and multicultural. Epigravettian should be considered as a polygenetic phenomenon characterized by a cultural mosaic peculiar to specific geographical regions. In relation to the territory of the Desna and the Middle Dnieper Basin, we can assume a direct continuity between the local Gravettian and Epigravettian traditions, despite changes in technology and typology of stone and bone tools, as well as the style in the design of portable art objects.

Anti-friction properties of solid lubricating coatings dedicated for the decrease in friction and increase in seizure resistance in the piston skirt–cylinder liner couple of high-forced combustion engines have been compared. Various modifications of coatings based on a polymer binder with addition of high-purity molybdenum sulfide and graphite have been deposited onto the segment surface. The graphite-based coating (foreign manufacturer), which is now successfully employed for steel pistons in diesels of heavy vehicles, has been used as the reference specimen. The studies were carried out at the friction temperature of 110°С in the range of normal loads of 50–450 N at a constant reciprocating frequency of 20 Hz, which is comparable to operating conditions of tribocoupling in diesel engines. Analysis of the results has shown that deposition of all coatings significantly decreases the friction coefficient, which amounts to 0.12–0.14 in some coatings (containing simultaneously molybdenum disulfide and graphite), which corresponds to the condition of contact of friction surfaces in the presence of lubricating material and the absence of direct metal contact in the friction couple.

Contamination of the sample with DNA is a problem when isolating RNA by phenol-chloroform extraction, and DNase treatment introduces an additional error in the analysis of gene expression. Bearing in mind the ability of LiCl to precipitate RNA selectively, we studied the possibility and advantage of using LiCl as a precipitation agent in the protocol for RNA precipitation [3] from frozen segments of large vessels. Combined use of LiCl with isopropanol as precipitating agents (optimal ratio 2.5 M and 40%, respectively) significantly eliminates negative effects of using this salt (inhibition of reverse transcription and low RNA yield).

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 solution to the problem of increasing the resource of an internal combustion engine (ICE) is directly related to the reduction of energy losses to overcome friction in the elements of systems, mechanisms and complexly loaded tribounits. A special place among the mechanical friction losses is occupied by the hydromechanical friction losses in the ICE tribounit. A complex loaded tribounit is characterized by loadings that are variable in time and magnitude, at which the position of the movable element in conjunction is characterized by high eccentricities. Such a complexly loaded tribounit includes the main and connecting rod bearings of the crankshaft, the interface “piston skirt-cylinder liner” and “piston ring-cylinder liner” and thrust bearings of the ICE, etc. The only way to reduce oil starvation is to texturize the contacting surfaces, which will increase the bearing capacity of a heavily loaded bearing by creating many “micro wedges”. In particular, the texturing of the surface of the liners of the crankshaft bearings can be performed in the form of elliptical pits, which allow the oil to be stored on the friction surface under any operating conditions of the diesel engine. The article provides an overview of the main types of micro-texturing of a friction surface tribounit. The calculation model was created and the program of calculation analysis “crankshaft journal bearing” was developed. The calculations of hydromechanical characteristics are performed for various types of micro-texturing by the example of a connecting rod bearing in a diesel engine for commercial vehicles.

Purpose. Analysis of distortions in the de-ramped linear frequency modulated continuous wave (LFM-CW) signal reflected from an extended target (ET), which model is presented by a set of point scatterers. Definition of parameters affecting distortions in the de-ramped signal spectrum, and development of ET radar profile restoration methods. Methodology. Numeric computations method based on the equation describing the de-ramped LFM-CW signal of an ET. The de-ramped signal properties analysis by means of numeric computation with varying values of properties of the probing signal and the ET. Findings. Parameters of the transmitted signal and the ET model that affect the distortions have been determined: starting frequency, frequency change rate, the ET relative height, the distance between the reflectors, the limits of phase noise values. The spectrum distortion index has been introduced. Value. ET radar profile restoration methods that can be used for signal processing have been developed.

The paper aims at designing the advanced simulation model that is able to generate samples similar to human respiration signals typically acquired by a Doppler or Continuous-wave step frequency short-range radar system. The model is based on the continuous non-linear transformation of the mixture of a sine wave with amplitude and frequency modulation and a colored Gaussian noise. Despite not being based on a detailed physiological description of the respiration process, the proposed model can produce samples of respiration signals resembling the signals acquired by a radar with high accuracy. In contrast to the widely-used monoharmonic model, the model does not exhibit strict periodicity that allows researchers to consider it to be an appropriate sample generator for thorough testing procedures performed over existing algorithms of respiration signal detection as well as newly-created ones.

The paper describes the investigation of the effect of functionalized carbon 1D nanostructures (single- or multiwalled nanotubes, nanofibers with a relatively smooth or highly disordered outer surface) on the level of interfacial interactions in filled vulcanizates. It is found that functionalization of nanoparticles with carbon black is accompanied by formation of hybrid structures in phase of filler that leads to increasing vulcanizate stiffness. Functionalization of nanoparticles by polyfunctional polymers increases the level of interfacial interactions on the vulcanizate-textile cord border without deterioration of the complex of elastic-strength properties.

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 reliability of many machines and mechanisms is mainly determined by the reliability of friction pairs (in particular, journal bearings). So the journal bearings in the piston engine are mostly operated in the hydrodynamic lubrication regime and, at high loading levels, in the transient and mixed lubrication regimes. The latter is important for the determination of the service life of the tribosystem as a whole. For this aim, in this paper, we describe, develop, and apply an approach proposed earlier to build models of the interaction of rough surfaces for one of the tasks of simulation of tribological systems of the piston engine. Previously suggested models can estimate the area of contact, the friction force, coefficient of friction, wear, etc. However, this approach ignores the surfaces change and, consequently, contact and friction characteristics over the time. We described the general approach to build a model of interaction between rough surfaces, leading to the analysis of the Markov process. This method we applied for friction process and for the fatigue failure mode in which the surface element is destroyed after repeated contacts, the order of many millions. Given the initial data and the method of calculating the trajectory of movable elements on the lubricating layer taking into account rheological characteristics of lubricants, we determined the tribological parameters defining the resource of crankshaft bearings and the “piston–cylinder liner” tribosystem of the high forced piston engine.

The technique for determining the movable (holes in the crank bearing) and fixed (grooves on the surface of the pad) lubricant sources for lubricant supply to the heavy-loaded friction type bearing is considered. To determine the field of hydrodynamic pressures in the bearing lubrication layer, two modifications are taken into consideration: the modification of the algorithm for integrating the modified Elrod equation for the degree of the gap feeling. Further studies showed that developed modifications were proved to be quite effective in calculating the characteristics of the lubricating layer for both statically and dynamically loaded bearings. However, for the first modification, numerical oscillations of the unknown function at the boundary of the reduction of the lubricating layer were noticed. The second modification, for which the finite difference algorithm was used, is characterized by the simplicity of implementation and the stability of the iterative procedure. The example of connecting rod bearings of the crankshaft of the combustion engine is used to consider the influence of the location of the lubrication sources on the hydromechanical characteristics of complex loaded friction type bearings. Original schemes of location of partial and complete oil distribution grooves for lubricant supply for connecting rod bearings are proposed. It is shown that an additional method for improving hydromechanical characteristics is the selection of engine oil with improved viscosity–temperature characteristics.

The present paper discusses the spatial and stratigraphic analysis of an assemblage of archeological remains from the newly found point B (lettered in Cyrillic) of the Eastern Gravettian site Khotylevo 2. The new find was discovered by the Khotylevo Archaeological Expedition in 2005. The cultural layer of the site relates to a level of initial soil formation at the base of the Desna loess horizon. The stratigraphic position of the cultural layer at point B is typical of the entire Khotylevo 2 site and does not differ substantially from those at points А and Б. Currently, two closely related assemblages of archeological remains have been discovered at point B over an area of 45 m 2 . The first assemblage is noted for the presence of rounded shallow pits and embedded mammoth bones surrounding concentrations of bone coal; it also contains split animal bones, and flint splinters. Similar assemblages were discovered by F.M. Zavernyaev during the excavations at Khotylevo 2 in the 1970s. The second assemblage is marked by large clusters of intentionally arranged bones of woolly mammoth (Mammuthus primigenius). There is a certain pattern traceable in the bone arrangement, similar to those observed in mammoth bone structures of the Anosovka-Mesin dwellings. Microstratigraphic correlation of the two assemblages considered together with the radiocarbon dates strongly suggests them to be of different ages. The most abundant bone remains within the studied area belong to woolly mammoth. The list of mammal species identified from this site shows no significant difference from species lists known from other sites of the Russian Plain dated to the same chronological interval. The scarcity of bones belonging to other herbivorous mammals may be due to the fact that no butchering was performed at this part of the site. The abundance of mammoth bones does not directly indicate simultaneous overkill of those animals; it is quite possible, however, that individual animals were killed periodically.

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.

A method for evaluating the tribological parameters and service life of the piston-cylinder tribosystem of a diesel engine based on calculations and experimental studies is presented. This approach makes it possible to determine the calculated duration of contact between the friction surfaces of the tribosystem; to obtain an experimental dependence of the wear rate on the contact pressure in this friction pair; and, based on this, to evaluate the service life of the piston-cylinder tribosystem of the diesel engine taking into account the mode of its operation as a component of a machine.

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.

Optically active lactams were synthesized from (+)-3-carene and α-pinene enantiomers. Their properties and structures were characterized. A pathway for preparing their trifluoroacetate salts was demonstrated.

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.

Convective processes related to the onset of chaotic flows in a Hele-Shaw cell have been theoretically and experimentally studied. The properties of various modifications of a specific pulsation regime, in which certain characteristics exhibit chaotization with increasing Rayleigh number while the flow pattern remains statistically reproducible and retains a regular character, have been determined for the cavities with various ratios of the dimensions of wide sides. An analogy is established that allows pulsating vortices in the flow to be treated as simple coherent structures of a convective nature.

P*-Mono- and P*,P*-bidentate phosphorodiamidites containing the (S a )-1,1′-binaphthyl core and 1,3,2-diazaphospholidine rings were synthesized. The use of these compounds in the rhodium-catalyzed asymmetric hydrogenation, as well as in the palladium- and platinum-catalyzed asymmetric alkylation and amination, resulted in the formation of the products with ee of up to 99%.

The problem of calculating the hydromechanical characteristics of complex-loaded sliding bearings is formulated in which the cross section of the bearings is shaped to limit the lubricating layer and the shape is different from the ideal (round cylindrical) one. The results of calculation of the hydromechanical characteristics of the crankshaft connecting-rod bearing of a diesel engine are analyzed where the pivot journal and bush are oval.

Crankshaft rod bearings of a combustion engine are used as an example to show the technique and results of optimization of the design parameters of friction bearing under a complex load. The field of hydrodynamic pressures in a lubricating layer, which separates the crank pin and the bearing lining, is determined by integrating the equation for filling of the gap. This approach ensures observance of the condition of lubricant continuity at the boundaries of discontinuity and restoration of the lubricating layer. The lubricant viscosity, which is assumed to be an effective function of the temperature of the lubricating layer, is adjusted at each step of the calculation of the crank pin’s motion trajectory.

The planar chiral diaryl phosphorimidite ligand containing additional C-stereocenters and neutral and cationic palladium(II) chelates with this ligand, cis-[Pd(η2-P,N)Cl2] and [Pd(Allyl)(η2-P,N)]BF4, were synthesized for the first time. The possibility of using these compounds in asymmetric allylic alkylation of 1,3-diphenylallyl acetate with dimethyl malonate in an optical yield of up to 73% was demonstrated.

Previously unknown chiral P,N-bidentate N-pyrrolylphosphines and their chelate complexes [Rh(η2-P,N)(CO)Cl] and [Pd(Allyl)(η2-P,N)]BF4 were synthesized by phosphorylation of (E,1R,2R,3R,5S)-2-[(2,6,6-trimethylbicyclo[3.1.1]heptyl-3-)iminomethyl]-1H-pyrrole. The composition and structures of the novel compounds were determined by the 1H, 13C, and 31P NMR, IR, mass spectrometry (electrospray), and elemental analysis methods. N-pyrrolylphosphines were found to have unusual electronic properties, being simultaneously more strong π-acids and σ-bases as compared to phosphites.

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.

Chiral ferrocene-containing iminoarylphosphite ligands based on 4,4′-dimethoxy-6,6′-di-tert-butyl-biphenyldiol-2,2′ and their chelate complexes with Rh(I) and Pd(II) were synthesized for the first time. They were shown to be perspective reagents in the reactions of asymmetric allyl substitution. The Pd-catalyzed alkylation of 1,3-diphenylallylacetate with dimethyl malonate results in a 87% enantiomer excess (ee), while in sulfonylation of 1,3-diphenylallylacetate with sodium para-toluenesulfinite, this figure amounts to 67%. The results obtained were compared with coordination and catalytic efficiency of a less sterically hindered ferro-cenyliminophosphite based on pyrocatechol. The compositions and structures of new compounds were determined by the 1H, 13C, 31P NMR, IR, mass spectrometry (EI, FAB, and electrospray techniques), and elemental analysis.

A chiral P,N-bidentate aryl phosphite ligand containing peripheral (R)-(+)-camphor-derived ketimine and its rhodium(I) and palladium(II) chelate complexes were synthesized for the first time. These compounds were found to be suitable for asymmetric allylic substitution. The Pd-catalyzed sulfonylation of 1,3-diphenylallyl acetate with sodium p-toluenesulfinate gave the product in 73% ee; in the alkylation of the same substrate with dimethyl malonate, the ee was 94%. These ee values are higher than the enantioselectivity achieved with the known phosphine analogs.

The reaction of (4S,9S)-4,9-diethyl-2,11-dioxa-5,8-diaza-1λ5-phosphatricyclo[6.3.0.01.5]undecane (1) with [Pt(COD)Cl2] (COD = cycloocta-1,5-diene) at 0 °C gave [(1,2:5,6-η)-1,5-cyclooctadiene][(4S,9S)-4,9-diethyl-5H-5,8-diaza-2,11-dioxa-1λ5-phosphatricyclo[6.3.0.01.5]undecyl-1]chloroplatinum chloride (2). If the reaction was performed in the presence of AgBF4, the corresponding BF4- salt (4) was isolated. Complex 2 was converted to cis-dichloro{(4S,9S)-4,9-diethyl-2,11-dioxa-5,8-diaza-1-phosphabicyclo[6.3.0]undecane-P,N}platinum (3). Variable-temperature 31P NMR studies of complexes 2 and 4 have been carried out in the range from −93 to 50 °C. The structure of compound 4 has been determined by X-ray crystallography. Complex 4 has a slightly distorted trigonal-bipyramidal geometry around the phosphorus, with the platinum fragment in the equatorial position. The P−Nax bond distance is 2.002(5) A. The Pt atom exhibits a nearly square-planar coordination geometry.

The complex formation of bi- and tricyclic hydrophosphorane derivatives of isoleucinol with [Pt(COD)Cl2], [Rh(CO)2Cl]2, and [Rh(THF)2(COD)]+BF4– (COD is cycloocta-1,5-diene) was investigated. In all cases, bicyclic hydrospirophosphorane selectively forms the metal chelates [M(η2-P∩N)(X)Cl] (M = Pt, X = Cl; M = Rh, X = CO) and [Rh(η2-P∩N)(COD)]+BF4–. («∩» denotes the residue of the hydrospirophosphorane ligand, which does not contain the P and N atoms). In addition, tricyclic hydrophosphorane (L) generates the phosphoranide complexes [Pt(η1-L)(COD)Cl]+Y– (Y = Cl or BF4). The structures of the new compounds were established by IR spectroscopy, 31P, 13C, 1H, 2H, 11B, 19F, and 195Pt NMR spectroscopy, and plasma-desorption and electrospray ionization mass spectrometry. The possible mechanism of coordination of hydrophosphoranes is discussed.

The asymmetric synthesis of methyl 2-phenyl-2-(2-phenyl-ortho-carboran-1-yl)pent-4-enoate was carried out by palladium-catalyzed allylation in the presence of amino phosphites of the type (RO)2P—O—CH2—CHR"—NR″2 as chiral ligands.

Phosphorylation of (S)-prolinol with P(NEt2)3was used to synthesize aminophosphite (2R,5S)- $${\text{HCH}}_{\text{2}} {\text{OPNEt}}_{\text{2}} $$ , which was reacted with the corresponding amino alcohols to afford (2S,5R)- $${\text{CH}}_{\text{2}} \left( {{\text{CH}}_{\text{2}} } \right)_2 {\text{NCHCH}}_{\text{2}} {\text{OPO}}\left( {{\text{CH}}_{\text{2}} } \right)_2 {\text{NMe}}_{\text{2}} $$ (Va) and (2S,5R)- $${\text{CH}}_{\text{2}} \left( {{\text{CH}}_{\text{2}} } \right)_2 {\text{NCHCH}}_{\text{2}} {\text{OPO}}\left( {{\text{CH}}_{\text{2}} } \right)_2 {\text{N}}\left( {{\text{CH}}_{\text{2}} } \right)_{\text{4}} {\text{CH}}_{\text{2}} $$ (Vb). Reaction of Vawith [Rh(CO)2Cl]2(P/Rh = 1) yields the mononuclear chelate [Rh(CO)(P^N)Cl] (VIIa), while the analogous reaction with Vbresults in a mixture of products with cis- and trans-orientation of the coordinated phosphorus and nitrogen atoms. Spectral characteristics of the products of coordination of ligands Vaand Vbwere compared with those for the binuclear reference complex [Rh(CO)(L)Cl]2(VIII), where L is P-monodentate ligand (2S,5R)- $${\text{CH}}_{\text{2}} \left( {{\text{CH}}_{\text{2}} } \right)_2 {\text{NCHCH}}_{\text{2}} {\text{OPOEt}}_{\text{2}} $$ (VI). The ligands and complexes were studied by IR, NMR, 31P and 13C spectroscopy, mass spectrometry, and elemental analysis methods. X-ray diffraction analysis of crystals VIIIwas performed.

Published data on the synthesis of rhodium and palladium complexes with optically active P,N-bidentate ligands and their applications in homogeneous asymmetric catalysis are summarised and discussed. The effect of the nature of the P,N-bidentate compounds on the structure of the metal complexes and on enantioselectivity in catalysis is examined. Allylic substitution, cross-coupling, hydroboration and hydrosilylation catalysed by Rh or Pd complexes with optically active P,N-bidentate ligands are considered. The prospects for the development of this field of chemistry are demonstrated. The bibliography includes 186 references.

Reactions of phosphoramidites based on (−)-ephedrine and [(1S)-endo]-(−)-borneol with the complexes M(COD)Cl2 (M is Pd or Pt, and COD is cycloocta-1,5-diene) were studied. The formation ofcis andtrans complexes of the general formulas MCl2L2 and M2Cl2(μ-Cl)2L2 was observed. The structures of the resulting compounds were established by31P,13C, and195Pt NMR and IR spectroscopy and by plasma desorption mass spectrometry.

Monolayer physical adsorption has been considered, taking into consideration the intrinsic volume of the adsorbate molecules. Since an adsorbed molecule occupies not only the site on the surface but also some of the neighboring volume, it creates steric difficulties for the adsorption of other molecules and leads to underestimation of the measured surface area. As a result, this value depends on the size of the adsorbate molecules and the apparent surface dimension can be introduced, even if the surface of narrow pores has no irregularities of atomic scale size. This effect was shown by simulation of adsorption on the surface of Menger sponge. Experimental data for measuring D-values on silica gels with different pore size distributions are in line with this effect.

The overall results of the study of hydrophosphorane compounds as ligands for metal complex synthesis and catalysis are summarised and discussed. The principal types of coordination of hydrophosphoranes, the structure of their metallo-derivatives, and the possible mechanism of the complex formation reaction are examined. The prospects for the employment of hydrophosphoranes in modern coordination design are demonstrated. The bibliography includes 102 references.