Use of liquid sealants to protect still-waste-containing tanks-settling basins from corrosion

Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 10, pp. 29–31, October, 1992.     

Temperature jump across a plane interface for a phase transition in a pure liquid

We develop a theoretical model of the development of a temperature jump across the boundary between phases during a phase transition in pure liquids.Notation G₁ mass flux of molecules of the liquid into the liquid - G₂ mass flux of molecules of the liquid into the vapor - G_v mass flux of vapor molecules - T₁ vapor temperature near the liquid surface - T₂ temperature of the liquid - T_v vapor temperature - R universal gas constant - c_p, c_v specific heats - r heat of vaporization - q heat flux density - K ratio c_p/c_v - parameter of the phase transition - F₀ area of the interface - P₁ pressure of the liquid - P₂ phase transition pressure - P_v vapor pressure Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 54, No. 5, pp. 793–797, May, 1988.     

Study of thermal and gasdynamic characteristics of a subsonic plasma air jet

Results are presented from a numerical analysis and experimental study of the enthalpy and velocity distributions along and across a subsonic plasma air jet.Notation x, r axial and radial coordinates - u, v axial and radial components of velocity - density - viscosity - emissivity - r_0.5 radius at which local value of velocity or enthalpy is half its axial value - , radii of dynamic and thermal boundary layers - q heat flux, kW/m² - h, h_w stagnation enthalpy and enthalpy at wall temperature, kJ/kg - p, p stagnation pressure and static pressure, Pa - R radius of curvature of spherical front part of body Indices 0 teconditions at nozzle edge - m conditions on jet axis - conditions on outer boundary of jet Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 42, No. 1, pp. 34–39, January, 1982.     

Development of algorithmic support for the analysis of stochastic systems based on canonical expansions of random functions

In the paper, we give a brief review of the known algorithmic and programm support for solving problems of nonlinear analysis of stochastic systems. Examples with the results of work of software tools in MATLAB are represented.     

Structure of protein solutions. Part 1. Investigation and interpretation of viscosity anomalies

The state of proteins in water-protein systems was investigated qualitatively using viscosimetric technique and preparative ultracentrifugation. In the case of cooperative processes, 4 concentration intervals bounded by three critical concentrations have been found for each protein. The first value of critical concentration is bound up with the initiation of supermolecular formations (herein also referred to as associates) due to self-association of polypeptide chains. The second critical concentration is observed when the weight fraction of associate becomes predominant (80–85%) and when the change of secondary and tertiary structures is completed. The third critical concentration is connected with the change in the nature of supermolecular formations. The thermodynamic stability of the water-protein system varies when the critical concentrations are passed through. The system is stable and, apparently, close to the true solution over the first concentration interval. As soon as the first critical concentration is reached, colloid particles appear in the system and become predominant after the second critical concentration is passed, and the solution should be considered as a colloid one.     

The X<Superscript>+</Superscript> trion in a system with spatial separation of the charge carriers

A system composed of two heavy holes located in a two-dimensional (2D) quantum well (QW) and bound via mediation of an electron in a neighboring 2D QW is considered. Using a simple qualitative trial wave function, the ground-state energy of this kind of X⁺ trion is determined in the infinite-hole-mass approximation as a function of the QW spacing. Coordinate dependence of the effective potential binding the holes to each other is calculated for different values of QW spacing. In the adiabatic approximation, a set of dependences describing the X⁺ trion binding energy as a function of the electron mass to the hole mass ratio is obtained. Several estimates for the trion binding energy in GaAs-and ZnSe-based double-QW heterostructures are given.     

Luminescence of Spatially Ordered Self-Assembled Solitary Ge(Si) Nanoislands and their Groups Incorporated into Photonic Crystals

Semiconductors - The luminescence properties of arrays of spatially ordered self-assembled solitary Ge(Si) nanoislands and their groups, including those embedded in two-dimensional photonic...     

The binding energy of excitons and <Emphasis Type="Italic">X</Emphasis><Superscript>+</Superscript> and <Emphasis Type="Italic">X</Emphasis><Superscript>−</Superscript> trions in one-dimensional systems

The exciton and trion states in semiconductor quantum wires are treated by the variational method. Simple trial functions provide an adequate precision of the calculation over a wide region of wire radii, with an arbitrary relation between the effective masses of charge carriers. The precision of the results obtained by the variational method is checked by numerical diagonalization of the Hamiltonian of excitons and positively and negatively charged trions. The asymptotic behavior of the binding energies of excitons and trions in narrow quantum wires is established in the analytical form. The structure of the excited X ⁺ trion states is analyzed in the context of the adiabatic approximation.     

Laser-Printed Plasmonic Metasurface Supporting Bound States in the Continuum Enhances and Shapes Infrared Spontaneous Emission of Coupled HgTe Quantum Dots

In order to advance the development of quantum emitter-based devices, it is essential to enhance light-matter interactions through coupling between semiconductor quantum dots with high quality factor resonators. Here, efficient tuning of the emission properties of HgTe quantum dots in the infrared spectral region is demonstrated by coupling them to a plasmonic metasurface that supports bound states in the continuum. The plasmonic metasurface, composed of an array of gold nanobumps, is fabricated using single-step direct laser printing, opening up new opportunities for creating exclusive 3D plasmonic nanostructures and advanced photonic devices in the infrared region. A 12-fold enhancement of the photoluminescence in the 900–1700 nm range is observed under optimal coupling conditions. By tuning the geometry of the plasmonic arrays, controllable shaping of the emission spectra is achieved, selectively enhancing specific wavelength ranges across the emission spectrum. The observed enhancement and shaping of the emission are attributed to the Purcell effect, as corroborated by systematic measurements of radiative lifetimes and optical simulations based on the numerical solution of Maxwell's equations. Moreover, coupling of the HgTe photoluminescence to high quality factor modes of the metasurface improves emission directivity, concentrating output within an ≈20° angle.