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The results obtained by the method of secondary ion mass spectrometry study of the initial stages of hydrogen interaction with the LaNi5 alloy surface are presented. It is demonstrated that the alloy surface is partially covered with a layer of island-structure oxides. Upon impinging on clean surface regions, hydrogen forms chemical compounds with both (nickel and lanthanum) alloy components. When the amount of hydrogen increases, hydride structures with different stoichiometric compositions involving both alloy components are formed on the surface and in the near-surface region. [ABSTRACT FROM AUTHOR]

The main parameters of ion-photon emission are investigated under ionic bombardment of metal-containing organic dyes and their mixtures with cholesterol. The spectral composition, quantum yield, and spatial distribution of emission from knocked-out excited particles have been determined. Several assumptions about the processes inherent to organic compounds under consideration have been made on the basis of the received data. [ABSTRACT FROM AUTHOR]

Non-steady-state ensemble arc behavior has been observed during the Vacuum Arc Remelting (VAR) of 508-mm-diameter ingots of INCONEL 718. The liquid metal flow in the melt pool of a 508-mm ingot during VAR has been simulated under two alternative sets of conditions: (1) a steady-state axisymmetrical arc distribution, as has been typically used in modeling work previously; and (b) a transient asymmetrical arc distribution. Due to the computational requirements, neither mass flux nor solidification were modeled; instead, the pool shape was fixed from measurements from a 508-mm-diameter ingot, and a constant pool wall temperature of 1609 K was used. The transient simulation assumed a localized Gaussian arc whose effective center was located at a distance of 0.1 m from the ingot centerline; this simulation rotated clockwise around the centerline with a period of 36 seconds. The steady-state model was simulated with axisymmetrical distributions of current and power input to the pool top surface calculated by time averaging the transient current and power inputs. The standard k- ε solver of ANSYS CFX 5.6 software was used for both simulations. The transient model results suggest that 5 seconds of asymmetrical arc behavior is enough to change the pool from steady state to transient and that, after 30 seconds, the flow is almost fully developed (at least to the accuracy of the model) and dominated by the Lorentz force. Aspects of the model results agree with key features of the melt pool observed during VAR. [ABSTRACT FROM AUTHOR]

The kinetics of the decomposition of hydrogen peroxide in the presence of heterobimetallic complex compounds [M1(L1/L2)][M2Cl4] (M1=Ni, Cu; M2=Zn, Mn; L1=4,6,6-trimethyl-1,9-diamino-3,7-diaza-3-nonene); L2=1,15-dihydroxy-7,9,9-trimethyl-3,6,10,13-tetraaza-6-pentadecene), obtained by direct template synthesis, were studied. It was shown that the copper compounds have high catalytic activity, whereas the nickel complexes are inactive. A mathematical model is proposed for description of the kinetic relationships, and the main characteristics of the process are obtained. [ABSTRACT FROM AUTHOR]

The analysis of main published results of studies of retention and migration of ion-implanted hydrogen isotopes and helium in tungsten and tantalum coatings, formation of radiation damages of the crystal lattice and their interaction with implanted gases, as well as the influence of helium and deuterium on various properties and surface morphology of coatings was carried out. The irradiation of samples was performed by beams of accelerated ions of hydrogen isotopes or He+, and in a plasma containing these ions, at various fluences and energies of incident ions, and at various temperatures of targets during implantation. Special attention was paid to the research results obtained at simultaneous irradiation of W both in bulk and in thin-film form. The used methods were electron microscopy, reemission mass spectrometry, thermal desorption spectrometry, X-ray photoelectron spectroscopy, X-ray diffraction, nuclear reaction analysis and Rutherford ion scattering. [ABSTRACT FROM AUTHOR]

Abstract: Alumina has been used as a mould face coat material for investment casting titanium alloys for many years; the interaction between the Al2O3 and the alloys are exemplified by a hardened layer formed at the alloy interface. In this research, the interaction between the Al2O3 face coat and a Ti–46Al–8Nb–1B alloy was investigated by modelling the cooling profile of the mould during casting. The interaction between the mould and metal was identified from the hardened layer thickness and metal/shell interface microstructural changes. Results showed that a high mould pre-heat temperature and large bar diameter will enhance the interaction between the shell and the TiAl alloy. During the casting process, not only was oxygen observed penetrating into the metal through the decomposition of the face coat materials, but also silicon from the backup coat was found to interact with the metal during the casting process. [Copyright &y& Elsevier]

As a component of multi-functional safety control, the man-machine mine shaft alarm system ensures safe conveyance of personnel and cargo in mines. The designed interfaces, circuits and architectures, hot backup and the objective-coordinated communication protocols guarantee strict orderliness, reliability and safety of mine control. [ABSTRACT FROM AUTHOR]

Casting of titanium based alloys presents considerable problems including the extensive interactions that occur between the metal and refractory. An investigation was undertaken to develop a zirconia facecoat suitable to replace current zircon/silica facecoat used in investment casting titanium aluminide alloys. The stability of the zirconia slurry was assessed using pH, viscosity and plate weight, and the mould properties such as friability, strength and permeability were measured. The interaction between the zirconia face coat and a Ti–46Al–8Nb–1B alloy was studied by centrifugal investment casting at three mould pre-heating temperatures. Computer simulation of metal cooling profiles during casting was also carried out to assist the analysis. In this work, a stable zirconia slurry was developed, and the moulds produced using a zirconia facecoat have comparable mechanical properties and better permeability than those made of the traditional zircon/silica facecoat. The friability of the zirconia facecoat was much improved in comparison to that made of yttria face coat. During casting, metal non-fill defects were presented at a low preheat mould temperature of 500 °C. The interaction products found between the metal and mould included a combined (Ti, Zr) 5 (Si, Al) 3 and ZrAl 2 phases, a re-precipitated ZrO 2 phase, and a Al 2 O 3 film at the interface. The interaction between mould and metal also caused a high hardness at the interface due to oxygen penetration, which varied with samples using different mould pre-heat temperatures. The suggestion has been made that the mould pre-heat temperature should be less than 1200 °C. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cells (DSCs) have great potential to provide sustainable electricity from sunlight. The photoanode in DSCs consists of a dye-sensitized metal oxide film deposited on a conductive substrate. This configuration makes the photoanode a perfect sample for laser desorption/ionization mass spectrometry (LDI-MS). We applied LDI-MS for the study of molecular interactions between a dye and electrolyte on the surface of a TiO2 photoanode. We found that a dye containing polyoxyethylene groups forms complexes with alkali metal cations from the electrolyte, while a dye substituted with alkoxy groups does not. Guanidinium ion forms adducts with neither of the two dyes., (Copyright © 2015 John Wiley & Sons, Ltd.)