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The problems associated with the physics of heterogeneous pool boiling at a low pressure on a flat horizontal surface are considered. The examples of parametric mismatch between the trends are connected with the thermophysical properties and wall surface microgeometry, with the size of the working area, with the affected zone of a growing bubble, and with the contact angle at the interface between the liquid, solid, and vapor phases. A conclusion is drawn concerning the possible causes of ambiguity in the results of the simulation of nucleate pool boiling modes under calculation of the individual contribution of each of the heat transfer mechanisms (convection, liquid microlayer evaporation, and rearrangement of the thermal boundary layer after bubble detachment). It is emphasized that the problem should be solved in the 3D conjugate formulation.

Experimental data obtained at VTI for the onset of nucleate boiling of water in a uniformly heated pipe with a diameter of 5.77 and 6.34 mm at a mass flow rate Wj = 1400–5000 kg/(m2 s) and at a pressure of P = 9.81, 14.7, 19.62 MPa are presented in comparison with a theoretical calculation on the homogeneous nucleation mechanism in a metastable liquid for the liquid superheating limits obtained using the classical Gibbs formula [1]. It is assumed that the thermodynamic instability of the process in the area under the spinodal affects the breakage of metastable liquid films with the formation of holes through the entire thickness thereof, which ultimately leads to the formation of unwettable dry spots (spinodal dewetting) and causes a spontaneous transition to the film boiling mode.

The samples of porous silicon (por-Si) particles in three size ranges (60–80, 250–300, and 500–600 nm) are obtained by electrochemical anodic etching of single-crystal silicon in an electrolyte based on an HF solution, followed by a change in the modes of ultrasonic treatment and homogenization. A complex characterization of particles was carried out by scanning electron microscopy, photon cross-correlation spectroscopy, and X-ray photoelectron spectroscopy. In vitro biocompatibility models using unicellular organisms of infusoria Paramecium caudatum Keln are applied to demonstrate the low toxicity of the samples at concentrations used for intravenous administration. The systemic in vivo biodistribution was studied for the por-Si 60–80 nm sample using adult Wistar rats. Introduced nanoobjects are found in the liver and heart tissues without significant changes in shape or size and predominantly in the oxidized state. Possibilities of using por-Si samples as matrices for transporting pharmaceuticals with intravenous administration are studied by assessing the intensity of the ototropic effect of gentamicin. An objective audiologic method for studying the amplitude of otoacoustic emission revealed the largest otodepressive effect of gentamicin when submicrometer-sized por-Si particles (500–600 nm) was used as a disperse system for drug delivery. Thus, modifications of the conditions for the synthesis of por-Si nanoparticles are promising directions in obtaining physicochemical parameters of transport particles that are optimal for specific tasks of targeted drug delivery.

A low-temperature layered phase CuxTiS2 (0 ≤ x ≤ 0.7) has been prepared. The occupation of both octahedral and tetrahedral sites by the copper atoms in the interlayer gap of the TiS2 lattice is revealed. The presence of two concentration regions of 0 ≤ x ≤ 0.3 and 0.5 ≤ x ≤ 0.7, which differ in the concentration dependence of the unit cell volume, has been observed. In the first region the unit cell volume increases with x, in the second region it decreases. This difference may be associated with the competition between Cu-Ti and Cu-S covalent centres. The electrical and magnetic properties of the materials are in a good agreement with this assumption. The electronic structure of CuxTiS2 in the low copper concentrations region has been studied using X-ray photoelectron, resonant photoelectron and absorption spectroscopy techniques. It was found that, in the low copper concentrations region, the charge transfer from Cu to the conduction band of TiS2 along with the formation of covalent centres is observed.

Atomic composition of monolayers based on siloxane dimer of quaterthiophene deposited by Langmuir–Blodgett technique on a silicon dioxide surface partially covered by gold film and the stability of these monolayers upon surface treatment by Ar+ ions bombardment have been studied. Experimental results for the chemical composition of a series of studied surfaces have been obtained by X-ray photoelectron spectroscopy (XPS) by recording XPS spectra of C 1s, O 1s, S 2p, and Au 4f core levels. The relative concentration of Au and Si substrate atoms and the composition of ex situ prepared surface under study were determined within 10–15%, which indicates that Langmuir–Blodgett monolayers based on siloxane dimer of quaterthiophene form continuous coating in a considerable extent. Prior to the treatment of the studied surface by Ar+ ions bombardment, carbon- and oxygen-containing surface adsorbates provided a considerable contribution to the results of XPS measurements. The surface cleaning by Ar+ ions with energy 3 keV at electric current through sample of ~1 μA in several 30-s steps has led to the etching of surface adsorbates and next Langmuir–Blodgett films of the siloxane dimer of quaterthiophene.

The problems of simulation of heterogeneous nucleate pool boiling on a horizontal surface on the ascending branch of the boiling curve from the formation of a steam lens (SL) to the boiling crisis are considered. The proposed hypothesis provides in a number of cases a logically consistent interpretation of experiments and outlines the organizational principle of transferring the wall–liquid–steam system into the regime of nonwettable “dry spot” formation. The model includes the following types of nucleate boiling: (a) cyclic boiling with the contact line reverse to the bubble bottom center and bubble departure from the surface (at low heat flux q and the contact angle θ < 90°); (b) single steam bubble conversion into a steam lens, i.e., local film boiling with the possibility of spreading of a single “dry spot” at the variation of the contact angle θ ≥ 90°, and substantial growth of the departure diameter Dd and SL lifetime τd; (c) formation of a single steam cluster of four SLs at a given pressure, the liquid underheating, and the average wall overheating.

Conditions for the surface processing of a cap GaN layer in AlGaN/GaN high-electron-mobility transistor (HEMT) structures in a BCl3 plasma have been found. They make it possible to considerably reduce the resistance of ohmic contacts to Group III nitride-based field-effect transistors. The primary factor behind this effect is the noticeable lowering of a potential barrier on the GaN surface through the formation of nitrogen vacancies that act as donors and, correspondingly, a rise in the surface concentration of electrons.

The electronic structure of the NixTiSe2 intercalation compounds with disordered and ordered Ni atoms is studied using photoelectron, resonant photoelectron and X-ray absorption spectroscopy, theoretical calculations of the X-ray spectra and density of electronic states. The increase in the covalent component of the chemical bond of Ni and Ti with the nearest neighbour was found with increasing nickel concentration and its ordering. A significant charge transfer from the Ni atoms to the host lattice resulting in the transformation of Ti4+ into Ti3+ occurs, while the symmetry of the crystal lattice is lowered from the hexagonal to the monoclinic one.

A comparative investigation of graphene prepared by cracking of propylene (C3H6) on nickel surfaces with different orientations, Ni(111) and Ni(100), has been carried out using angle-resolved photoemission spectroscopy. It has been shown that the graphene formed on the Ni(111) surface is well ordered on a large surface area, whereas the graphene on the Ni(100) surface has a well-defined domain structure. It has been found that the electronic structures of the two systems are similar to each other, and graphene is strongly bound to the nickel substrate. It has been demonstrated that the intercalation of a gold monolayer for the two systems leads to the formation of an electronic structure that is characteristic of quasi-free-standing graphene.

The effect of the exposure time at recording an X-ray photoelectron spectrum on the valence state and environment of copper in mordenite-type zeolite has been studied. It has been found that X-ray irradiation under the conditions of the experiment results in the redistribution of copper ions between the existing forms determined by differences in their coordination but without change in their valence state.

An experimental study of the electronic structure of V

The electronic structure of the Ni

An experimental study of the electronic structure of copper intercalated titanium dichalcogenides in a wide range of copper concentrations (x = 0.05 - 0.6) using the x-rays photoemission spectroscopy, resonant photoemission and x-rays absorption spectroscopy has been performed. Negative energy shifts of the Ti 2p and Se 3d core levels spectra and a corresponding decrease of the photon energy in Ti 2p absorption spectra with increasing concentration of copper have been found. Such sign-anomalous shifts may be explained by the shielding effect of the corresponding atomic shells as a result of the dynamic charge transfer during the formation of a covalent chemical bond between the copper atoms and the TiSe2 matrix., Comment: 12 pages, 6 figures

The results of calculating the parameters of heat transfer crisis regimes in uniformly heated tubes, obtained with the aid of look-up tables (LTs) Grnv-95 and FEI-91 are presented.

An experimental study of the electronic structure of VxTi1-xSe2 system in a wide range of vanadium concentrations (x = 0.06-0.9) using x-ray photoelectron spectroscopy and resonant photoelectron spectroscopy has been performed. The partial charge transfer from the VSe2 to TiSe2 structural fragments is experimentally observed, and the most part of the charge is localized on the vanadium atoms in the VSe2 structural fragments.

Empirical correlations are used to calculate the conditions for the appearance of a crisis of heat transfer in the core of a water-cooled reactor under normal operating conditions or during accidents. Experimental data obtained on models which simulate, to one degree of another, the geometry, the operating parameters, and the form of the radial energy-release field in real fuel assemblies are used to develop and verify such recommendations.

Problems of values, which have recently been recognized by psychologists (1), have some sociopsychological aspects, including the assimilation of values in the process of socialization, the role of values in the integration of actions of social groups, and so on. In this paper only one of these aspects is touched upon. We shall deal with analysis of the sociopsychological mechanisms that allow values to influence a person's behavior — but only to the extent to which this has been worked on empirically and, especially, experimentally, within sociopsychological science. Owing to the lack of development of the particular discipline, this relatively narrow task requires at least a preliminary statement of what will be understood by "value" in empirical sociopsychological research, the characteristics distinguishing values from other regulators of social behavior, such as norms, goals, motives, and personality traits.