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The deposition of LiCoO2 nanosized particles synthesized in LiCl–CoCl2 melts on the surface of nickel foil, copper, chrome–cobalt alloy, and platinum mesh in aqueous solutions of lithium chloride at the room temperature as well as on the surface of the electron-conducting La0.6Sr0.4MnO3 oxide ceramics in chloride melt at temperature of ca. 700°C is studied. The methods of vibrational spectroscopy, X-ray photoelectron spectroscopy, ellipsometry, and scanning electron microscopy have revealed the features of the chemical composition, structure, and morphology of the precipitates obtained. [ABSTRACT FROM AUTHOR]

The interaction of the monel alloy and its corrosion resistance in a melt of alkali metal carbonates in an oxidizing atmosphere was studied. The selectivity of alloy dissolution and modification of the electrode surface after storage at a constant anode potential were analyzed. The generation and development of local corrosion defects (pit corrosion, intercrystallite corrosion, corrosion cracking) on monel alloy (70% nickel, 28% copper), copper, and nickel electrodes in the molten eutectic of lithium, sodium, and potassium carbonates at a working temperature of 773 K were studied. The anode polarization was accompanied by a change in the state of the electrode surface. [ABSTRACT FROM AUTHOR]

The dissolution of L63 brass in molten alkali metal carbonates is shown to occur at an operating temperature of 773 K in the potentiostatic and galvanostatic regimes. The size and number of pores are found to depend on the electrochemical parameters, namely, the applied potential and the current density. [ABSTRACT FROM AUTHOR]

Nanothin spatial dissipative structures (SDSs) produced by thermal gradient processing of an amorphous selenium film by means of one-sided heating of its lower surface at T = 413 K have been studied by transmission electron microscopy and microdiffraction. It has been established that the resulting nanothin SDSs of hexagonal selenium possess a specific curved habit and a nonlinear fan-shaped system of bending contours in their electron-microscopic image; the lattice of nanothin SDSs undergoes elastic-plastic rotational curvature around three mutually perpendicular directions; the lattice rotation angles of nanothin SDSs of hexagonal selenium reach 25° around [001], 32° around the direction perpendicular to [001] and lying in the plane of the amorphous film, and 35° around the direction perpendicular to the first two directions and not lying in the plane of the amorphous film. [ABSTRACT FROM AUTHOR]

The effect of temperature in the range from 350 to 650°С on the morphology of L63 brass (37 wt % Zn) during selective anodic dissolution in the eutectic salt melt of lithium, cesium and potassium chlorides is studied. Anodic polarization is accompanied by a change in the state of electrode surface due to the passage of the electronegative alloy component (zinc) into a corrosive medium and to the vacancy-induced rearrangement of the electropositive component (copper). Microscopy, gravimetry, chemical analysis, and hydrostatic weighing are used to estimate the laws of formation of a developed anode surface under galvanostatic conditions of the electrochemical dissolution of the bimetallic alloy. An increase in the temperature leads to a decrease in the selectivity of alloy dissolution, the porosity, and the developed surface of the materials. [ABSTRACT FROM AUTHOR]

Abstract: By analyzing the patterns of flexural extinction contours present on the electron-microscopic images of nanothin (~80 nm) spatial dissipative structures (SDSs) of hexagonal selenium, i.e., nanothin crystals with elastic rotational curvature of the lattice around [001], the processes of formation of torn interblock boundaries in these structures are investigated. The effect of changing the disorientation-vector sign along the torn interblock torsion boundaries is observed. A model of formation of interblock torsion boundaries is developed for nanothin selenium SDSs, the lattice of which undergoes an elastic rotational curvature around [001]. [ABSTRACT FROM AUTHOR]

The symmetry of direct and reciprocal lattices and the symmetry of bend contours present in the electron microscopy images of nanothin crystals with elastic rotational distortion of the lattice are examined using the example of nanothin selenium crystals. [ABSTRACT FROM AUTHOR]

Nanothin space-dissipative structures (SDSs) of hexagonal selenium formed in an amorphous film are investigated by transmission electron microscopy. It is established that the nanothin SDS of hexagonal selenium with a linear fan-shaped system of flexural contours in the electron-microscopy image is initial for the formation of the nanothin SDS of hexagonal selenium with a nonlinear fan-shaped system of flexural contours in the electron-microscopy image. It is shown that the formation of the nanothin SDS of hexagonal selenium with a nonlinear fan-shaped system of flexural contours in the electron-microscope image results in a change in the geometry of the nanothin-SDS lattice from Euclidean to Riemannian. [ABSTRACT FROM AUTHOR]

The formation of nanothin spatial dissipative structures (SDSs) of hexagonal selenium with elastic rotational curvature of the lattice about [001] in an amorphous film was considered. It was established that nanothin SDSs form in thermal gradient treatment of an amorphous film by one-side heating of its lower surface at T = 453 K. The state of pseudo-single crystal, which precedes the formation of a nanothin SDS in an amorphous film, is a state with a high concentration of vacancies. Under the action of the temperature difference ΔT, vacancies and selenium atoms undergo thermal diffusion in the direction perpendicular to the surface of the pseudo-single crystal. It was shown that, when ΔT reaches critical values, there is a transition from the structure of a pseudo-single crystal to the structure of a rhombic nanothin SDS of hexagonal selenium. The heat flux through the nanothin SDS in the direction perpendicular to its surface ensures the entropy export to the environment. After the thermal gradient treatment of the amorphous film, the nanothin SDS is quenched by cooling it in air; in this process, there is quenching of nonequilibrium structural defects-- atoms and vacancies displaced from equilibrium positions. The quenching makes the nanothin SDS stable. The formation of nanothin SDSs of hexagonal selenium with elastic rotational curvature of the lattice about 001] in an amorphous film occurs under conditions satisfying the theory of the formation of dissipative structures. [ABSTRACT FROM AUTHOR]

The corrosion-electrochemical behavior of a nickel electrode is studied in the melt of lithium, sodium, and potassium (40: 30: 30 mol %) carbonates in the temperature range 500–600°C under an oxidizing atmosphere CO 2 + 0.5O 2 (2: 1), which is partly replaced by gaseous chlorine (30, 50, 70%) in some experiments. In other experiments, up to 5 wt % chloride of sodium peroxide is introduced in a salt melt. A change in the gas-phase composition is shown to affect the mechanism of nickel corrosion. [ABSTRACT FROM AUTHOR]

The corrosion-electrochemical behavior of titanium in a chloride melt containing 1-30 wt % sodium nitrate at a temperature of 790-900 K in an argon atmosphere is studied. Depending on the sodium nitrate content, either oxide layers of various structures can appear on the titanium surface or titanium dioxide nanopowder can form in the bulk of the melt. Treating VT-1 titanium with hydrogen or helium high-temperature pulsed plasma substantially changes the morphology and protective properties of the oxide films produced on titanium. [ABSTRACT FROM AUTHOR]

The effect of high-temperature pulsed plasma (HTPP) on the corrosion-electrochemical behavior of titanium in a molten eutectic mixture of cesium and sodium chlorides in an argon atmosphere at temperatures of 790–810 K is studied. Upon the HTPP treatment in an oxygen or helium environment, a modified corrosion-resistant layer with a thickness up to 20 µm is formed on the titanium surface and decreases the corrosion rate of titanium in a chloride melt by a factor of 10–16. [ABSTRACT FROM AUTHOR]

The effect of NTPS inhibitor on the corrosion behavior of magnesium alloys with various contents of alloying components is studied. NTPS is found to be an effective corrosion inhibitor in the absence of energizing, but under the anodic polarization, it does not produce any noticeable effect on the self-dissolution process. Comparative analysis of the processes proceeding at the anodic dissolution of magnesium and electron-microscopic studies of the specimens showed that the dissolution is accelerated due to the active-surface development. A supposition that, under the effect of a constant anodic current, the development and formation of the magnesium surface relief takes place at the initial polarization stage is put forward. [ABSTRACT FROM AUTHOR]

At the oxidation of zirconium in molten salts up to 813–1073 K, the growth of oxide phases is found to proceed chiefly due to the diffusion of oxygen ions via the oxide film toward the metal-oxide interface. An oxide film formed in the initial period of zirconium oxidation in a chloride-nitrate melt decelerates the process but does not prevent the ion exchange at the metal-melt boundary. As the oxide formation proceeds and the steady-state conditions of the corrosion process are reached, the oxidation rate becomes limited by the diffusion of oxygen ions from the film surface deep into the metal. Along with the diffusion of O2− ions at temperatures of 813 to 1073 K, zirconium ions can also migrate in the metal, which makes interpreting the whole process much more difficult. At the oxidation, the films of various colors (from black to light gray) with diverse corrosion and protective properties, as well as fine-dispersed powder of zirconium dioxide with a mean size of particles up to 30 nm, are formed. [ABSTRACT FROM AUTHOR]