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In dealing with modern linguistic semantics what draws attention is that the explanation of the meanings of language units is commonly made from the standpoint of intentionalism and mentalism. However, the explanation of some semantic phenomena is impossible from such a position. For instance, it is evident when teaching such a tense-aspect verbal form as the English perfect. The difficulties involved in trying to explain the meaning of the grammatical form reflect the important philosophical issue of the meaning of a word. The difficulties with explaining the meaning of the grammatical category suggests that there must be shortcomings in the mentalist approach to the explanation of semantics. One of the drawbacks of traditional approaches to the perfect tense semantics is that the basic meaning of this grammatical category is not fully revealed. To reveal it, it seems appropriate to refer to the diachronically original meaning of this verbal form it used to have before the grammaticalization of this initially syntactic possessive construction. An analysis of the semantic evolution of the perfect gives the impression that the functioning of this grammatical form is accomplished not entirely in line with the mental semantics that is usually attributed to it. In this regard, attention is drawn to the semantic approach to explaining the meaning of a word that is found in the works of proponents of analytic philosophy. The situation with the English perfect resembles what these authors say about non-mentalist assigning of meanings to words. Contemporary English speakers use the perfect in accordance with non-mental activity patterns they learn in the course of social practice, which to some extent reflect the meaning of the initial possessive structure the modern perfect developed from. At the same time, a mental meaning in the mind of a person apparently does not fully reflect the «objective» meaning of this grammatical category. The above considerations have implications for the philosophy of mind and language. Even if we are not willing to completely abandon the mentalist views, we still have to agree that mechanisms that can provisionally be called behaviorist or functionalist play a significant role in human activity.

Results of the synthesis of multilevel nanometre-sized cermets with interpenetrative structure based on -Bi₂O₃/Ag, for selective medium-temperature oxygen membranes needed for novel clean coal-based power engineering are presented. In particular, the size of crystallites of the components was decreased to 10-20 nm; the composition of the ceramics was improved by adding Pr; silver is doped heterogeneously by fluorite, with the conservation of compatibility and with increased fraction of silver in cermet with interpenetrative structure; nanocermets are modified with Pd. In spite of the significant improvement of the composite characteristics in comparison with known cermet 60Bi_0.75Er_0.25O_1.5/40Ag, the problem of making a real material for membranes has not been solved. Membrane degradation in all positions at T ~ 600 °C comes to the forefront. Along with optimization of the composition and method to obtain membrane material, it is proposed to decrease the working temperature to T ~ 500 °C.

Aluminium oxide systems were studied using a set of X-ray diffraction methods: Rietveld method, modelling of diffraction patterns of one-dimensionally disordered materials, modelling of fine dispersed substances, method of the radial distribution of electron density. Modelling of diffraction patterns of aluminium hydroxide and the curves of the radial distribution of electron density of oxides and hydroxides was carried out. Using the data of previous modelling, the real structure of aluminium hydroxides with different physicochemical properties and oxides obtained from them was studied. The results may be used in the analysis of any real object containing aluminium oxide systems, first of all nanometre-sized ones.

Nanopowders of α-Al₂O₃ were synthesized through crystallization of aluminium hydroxide gel with nanoparticles introduced into it as seedings. Depending on the gel crystallization conditions, the powder consists either of weakly aggregated spherical particles or of polygons with irregular shapes. It was established that particle shape is determined by the composition of the gas phase during crystallization, in particular by water vapour pressure. The temperature at which the gel is completely crystallized into the α-phase depends on the content of micro-impurities in the solution from which the gel is formed. Under optimal synthesis conditions, α-Al₂O₃ nanopowders with particle size about 100 nm are reproducibly obtained. The powders exhibit good moldability and sintering ability to form almost pore-free ceramics at 1300 ^oC.

Comparative analysis of two methods EXAFS and PDF to study the phase composition and local structure (interatomic distances and coordination numbers) of materials including nanomaterials was carried out. The shortcomings and advantages of the methods are considered.

Effect of mechanical activation (MA) of hexagonal boron nitride ( h BN) powder with different intensities in attritor and in a planetary ball mill (PBM) on the structure and phase composition of materials based on this compound was studied. Mechanical activation of h BN powder was carried out in order to decrease the parameters of synthesis of cubic boron nitride ( c BN) due to the formation of nanostructure in h BN. The stoichiometry of h BN is observed to decrease during MA due to partial decomposition. Mechanical treatment of h BN powders in PBM proceeds more intensively and leads to the formation of particles with crystallite size 5-10 times smaller than the size of crystallites formed during treatment in attritor. The specific surface increases by a factor of 3-6. After agglomeration of powders after MA at a pressure above 7 GPa, the phase composition of the resulting material is independent of the intensity of MA and is characterized by the presence of the cubic phase of BN alone.

Results of chemisorption measurements and experiments on hydrogen thermodesorption carried out with Pt/γ-Al₂O₃ samples with Pt nanoclusters (size <1 nm) are presented. The reasons of the reversible changes of adsorption properties were studied. The results are compared with the data for platinum nanoparticles (with the size mainly 2-3 nm) deposited on the “inert” oxide (SiO₂). The high sensitivity of chemisorption methods and temperature-programmable desorption to the changes in the state of supported metal clusters during thermal treatment of the samples in reducing and neutral media was demonstrated. It was shown that hydrogen adsorption on ultrafine systems is activated, and the adsorption capacity of samples determined from oxygen-hydrogen titration may decrease during multiple titration procedures. A strong effect of Н₂О on hydrogen thermodesorption from Pt/γ-Al₂O₃ samples reduced at high temperature was observed. The obtained results are interpreted taking into account the structural changes of nanoclusters in the low-temperature region and the formation of oxygen vacancies at the metal - support interface under the action of H₂ at high temperature.

Intra-mold modification of 110G13L steel was carried out using various dispersed modifying agents containing boron, tungsten, titanium carbides, ferrotitanium, and carbon as the active phase. To improve wettability, modifying agents were treated preliminarily with copper powder in AGO-3 planetary centrifugal mill. It was discovered that the microstructure of the formed steel samples is composed of austenite and carbides released inside the grains and along their boundaries. A significant increase in the point of maximal load by 14.5, 18.0 and 9.0 % was demonstrated by the steel samples treated with the modifying agents containing boron carbide (concentration of the active phase: 0.056 %), a mixture of tungsten and titanium carbides (0.033 %) and titanium carbide (0.083 %), respectively. In addition, the use of a mixture of tungsten and titanium carbides allowed us to increase relative elongation by 40 %. The use of the modifying agents containing boron carbide and a mixture of tungsten and titanium carbides promotes uniform distribution of carbides and a substantial decrease in grain size; the grain size (according to the State Standard GOST 5639) corresponds to two points (the actual grain diameter is 0.387-0.694 and 0.338-0.581 mm, respectively). The grain size in the reference sample is more than three points (the actual grain diameter is 2.325-3.168 mm). The grain size in other modified steel samples corresponds to three points and more.

Structural-chemical changes in high-silica zeolite-containing rocks from the Kholinskoye and Shivyrtuy deposits (Russia) under the action of mechanical activation in a laboratory vibrogrinder were studied by means of differential scanning calorimetry, thermogravimetry, densimetry, air permeability measurement, atomic emission spectroscopy with inductively coupled plasma, infrared spectroscopy, X-ray phase analysis. The kinetic parameters of dehydration of initial and mechanically activated natural zeolites were calculated (apparent activation energy, pre-exponential factor), as well as their thermodynamic potentials (enthalpy of formation, entropy and Gibbs energy), and disordering degree. The degree of carbonization of the samples under study was estimated with the help of the analysis of infrared spectra and thermogravigrams. It was demonstrated that the change of the reactivity of natural zeolites as a result of mechanochemical treatment is determined by the phase composition off initial samples.

Nickel boride Ni₃B is a promising material for making self-regulated heating elements. In the present work, the synthesis of nickel boride Ni₃B and its compaction were carried out for the first time by means of electric spark agglomeration. Two approaches were considered for obtaining sintered materials based on Ni₃B: 1) reactive electric spark agglomeration of the mixture of 3Ni + B subjected to preliminary mechanical treatment; 2) obtaining Ni₃B by means of thermal explosion in mechanically treated powder mixture, followed by compaction of the resulting product with the help of electric spark agglomeration. It was established that the material based on Ni₃B, obtained by reactive agglomeration, is characterized by lower content of admixture phase Ni₂B and higher relative density and microhardness in comparison with the material obtained by sintering the product of thermal explosion at the same temperature. Specific electric conductance of agglomerated materials based on Ni₃B is about 10^-3 Ohm x cm.