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General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Diagrammes de phases des métaux et alliages, Phase diagrams of metals and alloys, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Article synthèse, Reviews, Diagramme phase, Phase diagrams, Equilibre phase, Phase equilibria, Groupe espace, Space groups, Nickel, Rhodium, Section isotherme, Isothermal section, Sección isotérmica, Isothermer Schnitt, Structure cristalline, Crystal structure, Système ternaire, Ternary systems, Tantale, Tantalum, Transformation phase, Phase transformations, and Système Ni Rh Ta

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Surfaces et interfaces; couches minces et trichites (structure et propriétés non électroniques), Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties), Surfaces fluides et interfaces fluide-fluide, Fluid surfaces and fluid-fluid interfaces, Energie de surface (tension superficielle, tension interfaciale, angle de contact, etc.), Surface energy (surface tension, interface tension, angle of contact, etc.), Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Alliage binaire, Binary alloys, Alliage liquide, Liquid alloys, Antimoine alliage, Antimony alloys, Densité, Density, Dilatométrie, Dilatometry, Effet température, Temperature effects, Etain alliage, Tin alloys, Etude expérimentale, Experimental study, Etude théorique, Theoretical study, Tension superficielle, Surface tension, Volume molaire, Molar volume, and Volumen molar

Through the application of the maximum bubble pressure and dilatometric method, density and surface tension were investigated. The experiments were conducted in the temperature range from 583 K ≤ T ≤ 1257 K. The surface tension was measured for pure antimony and for six liquid Sb-Sn alloys (mole fractions XSn = 0.2, 0.4, 0.6, 0.8, 0.9, and 0.935 mm2) and measurements of the density were only for alloys. It has been observed that both surface tension and density show linear dependence on temperature. The temperature-concentration relation of both surface tension and density were determined with minimization procedures. The surface tension isotherms calculated at 873 K and 1273 K show slight negative deviations from linearity changes, but the observed maximal differences did not exceed 30 mN . m-1. The surface tension calculated from Butler's model was higher than the experimental value for most concentrations and also showed curvilinear temperature dependence. The experimental densities and the molar volumes of the Sb-Sn liquid alloys conform very closely to ideal behavior with differences comparable to the experimental errors.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Equations d'état, équilibres de phases et transformations de phases, Equations of state, phase equilibria, and phase transitions, Etudes générales des transformations de phases, General studies of phase transitions, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Diagrammes de phases des métaux et alliages, Phase diagrams of metals and alloys, Diagramme phase, Phase diagrams, Equation van der Waals, Van der Waals equation, Ecuación van der Waals, Equation état, Equations of state, Equilibre phase, Phase equilibria, Etude théorique, Theoretical study, Potentiel Yukawa, Yukawa potential, Potentiel paire, Pair potentials, Propriété thermodynamique, and Thermodynamic properties

In this paper, we modify the VDW equation of state by adding a temperature factor to it. As a result, we produce a good phase diagram and the correlation of the reduced pressure and the reduced temperature when a balanced liquid-gas coexistence canonical argon-like system is considered.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Diagrammes de phases des métaux et alliages, Phase diagrams of metals and alloys, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Aluminium, Diagramme phase, Phase diagrams, Diffraction RX, XRD, Equilibre phase, Phase equilibria, Etude expérimentale, Experimental study, Groupe espace, Space groups, Microscopie, Microscopy, Microsonde électronique, Electron microprobe, Microsonda electrónica, Elektronische Mikrosonde, Microstructure, Recuit thermique, Thermal annealing, Recocido térmico, Ruthénium, Ruthenium, Section isotherme, Isothermal section, Sección isotérmica, Isothermer Schnitt, Structure cristalline, Crystal structure, Système ternaire, Ternary systems, Titane, Titanium, Traitement thermique, Heat treatments, and Système Al Ru Ti

Phase relations in the ternary system Al-Ru-Ti were studied on arc-melted alloys and specimens annealed at 1100 °C, 950 °C, and 800 °C employing optical and electron microscopy, x-ray diffraction, and electron probe microanalysis. The results, in combination with an assessment of all literature data available, were used to construct liquidus and solidus surfaces, a series of isothermal sections, and a Schulz-Scheil diagram monitoring solidification (crystallization) in thermodynamic equilibrium. The crystal structure of the ternary G-phase was determined by x-ray single crystal diffraction to be a filled variant of the Th6Mn23-type (space group Fm3m). Furthermore, a new ternary compound with AuCu3-type structure was detected.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Diagrammes de phases des métaux et alliages, Phase diagrams of metals and alloys, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Aluminium, Article synthèse, Reviews, Diagramme phase, Phase diagrams, Equilibre phase, Phase equilibria, Fer, Iron, Propriété thermodynamique, Thermodynamic properties, Section isotherme, Isothermal section, Sección isotérmica, Isothermer Schnitt, Système ternaire, Ternary systems, Transformation phase, Phase transformations, Zinc, and Système Al Fe Zn

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Diagrammes de phases des métaux et alliages, Phase diagrams of metals and alloys, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Analyse thermodynamique, Thermodynamic analysis, Análisis termodinámico, Cobalt, Composé intermétallique, Intermetallic compounds, Diagramme phase, Phase diagrams, Energie libre Gibbs, Gibbs free energy, Energía libre Gibbs, Etude expérimentale, Experimental study, Etude théorique, Theoretical study, Fonction thermodynamique, Thermodynamic function, Función termodinámica, Modèle thermodynamique, Thermodynamic model, Système binaire, Binary systems, Vanadium, and Système Co V

A thermodynamic evaluation of the binary Co-V system has been done using experimental thermochemical and phase diagram data. A consistent thermodynamic description, using a Redlich-Kister model for solution phases and sublattice models for the intermetallics, was obtained, and it agreed well with the critically evaluated experimental data. The model for the solid phases accounts for the magnetic contribution to the Gibbs energy. The addition of a composition dependent magnetic term also led to the prediction of an fcc-Co miscibility gap. The model parameters have been determined using a computerized optimization technique. Several diagrams and tables concerning phase equilibria are presented.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Diagrammes de phases des métaux et alliages, Phase diagrams of metals and alloys, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Diagramme phase, Phase diagrams, Diffraction RX, XRD, Equilibre phase, Phase equilibria, Etain, Tin, Etude expérimentale, Experimental study, Fer, Iron, Microstructure, Section efficace, Cross sections, Section isotherme, Isothermal section, Sección isotérmica, Isothermer Schnitt, Système ternaire, Ternary systems, Zinc, and Système Fe Sn Zn

The Zn-rich corner of the 450 °C isothermal section of the Zn-Fe-Sn system was experimentally determined. Within the composition range explored in this study, the liquid phase was found in equilibrium with the ternary extensions of three binary Zn-Fe phases, the ζ, δ, and Γ1 phases. The ζ phase contains practically no Sn in solid solution; Sn solubility limits in the δ and Γ1 phases were 2.2 at. % and 7.0 at. %, respectively. The only Fe-Sn compound detected in this study was FeSn, which co-existed with the Γ1 phase. When its Sn content was lower than approximately 26 at. %, the liquid solidified in water quenching as a degenerated eutectic consisting of a mixture of η-Zn and β-Sn co-existing with primary ζ crystallites. When its Sn content exceeded approximately 70 at. %, the liquid transformed into metallic glass containing mostly Sn, Zn, and a small amount of Fe upon water quenching from 450 °C.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Diagrammes de phases des métaux et alliages, Phase diagrams of metals and alloys, Activité thermodynamique, Thermodynamic activity, Bore oxyde, Boron oxides, Bore, Boron, Diagramme phase, Phase diagrams, Equilibre phase, Phase equilibria, Etude théorique, Theoretical study, Modèle thermodynamique, Thermodynamic model, Propriété thermodynamique, Thermodynamic properties, Sodium oxyde, Sodium oxides, Sodium, Système quasi binaire, Quasi-binary systems, and Système B Na O

The Na2O3-B2O3 system is thermodynamically optimized by means of the CALPHAD method. A two-sublattice ionic solution model, (Na+1)P(O-2,BO3-3,B4O7-2,B3O4.5)Q, has been used to describe the liquid phase. All the solid phases were treated as stoichiometric compounds. A set of thermodynamic parameters, which can reproduce most experimental data of both phase diagram and thermodynamic properties, was obtained. Comparisons between the calculated results and experimental data are presented.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Diagrammes de phases des métaux et alliages, Phase diagrams of metals and alloys, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Chrome, Chromium, Diagramme phase, Phase diagrams, Etude expérimentale, Experimental study, Etude théorique, Theoretical study, Microstructure, Modèle thermodynamique, Thermodynamic model, Structure cristalline, Crystal structure, Système binaire, Binary systems, Zinc, and Système Cr Zn

The Cr-Zn binary system was critically assessed with the CALPHAD technique using the PARROT module of the Thermo-Calc software by taking into account new experimental measurements. The solution phases [liquid, body-centered cubic (bcc), close-packed hexagonal (cph)] were modeled with the Redlich-Kister equation. The intermetallic compounds CrZn13 and CrZn17 are treated as stoichiometric compounds. The experimental chromium solubilities at various temperatures modify the shape of the liquidus curve and are satisfactory for industrial applications. A set of parameters consistent with most of the available experimental data on both phase diagram and solubility measurements was obtained by optimization. A comparison with previous work is also presented.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Diagrammes de phases des métaux et alliages, Phase diagrams of metals and alloys, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Article synthèse, Reviews, Diagramme phase, Phase diagrams, Equilibre phase, Phase equilibria, Etain, Tin, Mercure, Mercury, Modèle thermodynamique, Thermodynamic model, Pression vapeur, Vapor pressure, Propriété thermodynamique, Thermodynamic properties, Système binaire, Binary systems, and Système Hg Sn

A thermodynamic assessment of the Hg-Sn system has been carried out using the CALPHAD method. The comprehensive assessment covers the extensive phase diagram data as well as the enthalpy, activity, and vapor pressure data. Two cases of intermetallic compounds in the Hg-Sn system are considered. Case 1 considers the intermetallic compounds β, γ, and HgSn4 as having no solubility and can thus be treated as the stoichiometric phases β-HgSn38, γ-HgSn12, and HgSn4. Case 2 uses a sublattice model to more accurately describe a solubility of the γ phase; it also considers the stoichiometric δ-HgSn7 phase. The e phase was considered to be metastable and neglected in the thermodynamic assessment. Thermodynamic parameters have been optimized using all the assessed experimental thermodynamic and phase equilibrium data. Both calculated phase diagrams of the Hg-Sn system (Cases 1 and 2) and the thermodynamic data are reasonable and satisfactory when compared with literature data. Future crucial experiments are suggested.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Diagrammes de phases des métaux et alliages, Phase diagrams of metals and alloys, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Article synthèse, Reviews, Equilibre phase, Phase equilibria, Fer, Iron, Fonction thermodynamique, Thermodynamic function, Función termodinámica, Modèle thermodynamique, Thermodynamic model, Propriété thermodynamique, Thermodynamic properties, Système binaire, Binary systems, Uranium, and Système Fe U

The Fe-U system is one of the binaries of the U-Fe-Zr-O quaternary system that is important for a safe nuclear program. A new thermodynamic assessment of Fe-U is presented, taking into account some recent thermodynamic measurements: enthalpy of formation and of melting as well as heat capacities for both intermetallic compounds Fe2U and FeU6. The calculated phase diagram and thermodynamic data generally agree very well with the experimental values. The calculated temperature of the peritectic transformation [FeU6 ↔ liquid + bcc-U] is equal to 1104 K, which is higher than in the previous assessments, but in agreement with Labroche's value. However, the experimental melting enthalpy of FeU6 is not reproduced by the present set of thermodynamic parameters.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Diagrammes de phases des métaux et alliages, Phase diagrams of metals and alloys, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Article synthèse, Reviews, Chrome, Chromium, Diagramme phase, Phase diagrams, Equilibre phase, Phase equilibria, Etude théorique, Theoretical study, Nickel, Section isotherme, Isothermal section, Sección isotérmica, Isothermer Schnitt, Système ternaire, Ternary systems, Titane, Titanium, and Système Cr Ni Ti

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Diagrammes de phases des métaux et alliages, Phase diagrams of metals and alloys, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Article synthèse, Reviews, Cobalt, Diagramme phase, Phase diagrams, Equilibre phase, Phase equilibria, Niobium, Section isotherme, Isothermal section, Sección isotérmica, Isothermer Schnitt, Système ternaire, Ternary systems, Transformation phase, Phase transformations, Tungstène, Tungsten, and Système Co Nb W

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Diagrammes de phases des métaux et alliages, Phase diagrams of metals and alloys, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Article synthèse, Reviews, Cobalt, Diagramme phase, Phase diagrams, Equilibre phase, Phase equilibria, Molybdène, Molybdenum, Section isotherme, Isothermal section, Sección isotérmica, Isothermer Schnitt, Système ternaire, Ternary systems, Tantale, Tantalum, and Système Co Mo Ta

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Diagrammes de phases des métaux et alliages, Phase diagrams of metals and alloys, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Article synthèse, Reviews, Cobalt, Diagramme phase, Phase diagrams, Equilibre phase, Phase equilibria, Niobium, Section isotherme, Isothermal section, Sección isotérmica, Isothermer Schnitt, Système ternaire, Ternary systems, Tantale, Tantalum, and Système Co Nb Ta

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Surfaces et interfaces; couches minces et trichites (structure et propriétés non électroniques), Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties), Surfaces fluides et interfaces fluide-fluide, Fluid surfaces and fluid-fluid interfaces, Energie de surface (tension superficielle, tension interfaciale, angle de contact, etc.), Surface energy (surface tension, interface tension, angle of contact, etc.), Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Alliage liquide, Liquid alloys, Argent alliage, Silver alloys, Etude expérimentale, Experimental study, Mesure densité, Density measurement, Mesure tension superficielle, Surface tension measurement, Propriété thermodynamique, Thermodynamic properties, Silicium alliage, Silicon alloys, Système binaire, Binary systems, Tension superficielle, and Surface tension

With the maximum bubble pressure method, the density and surface tension were measured for five Ag-Bi liquid alloys (XBi = 0.05, 0.15, 0.25, 0.5, and 0.75), as well as for pure silver. The experiments were performed in the temperature range 544-1443 K. Linear dependences of both density and surface tension versus temperature were observed, and therefore the experimental data were described by linear equations. The density dependence on concentration and temperature was derived using the polynomial method. A similar dependence of surface tension on temperature and concentration is presented. Next, the Gibbs energy of formation of solid Bi2O3, as well as activities of Bi in liquid Ag-Bi alloys, were determined by a solid-state electromotive force (emf) technique using the following galvanic cells: Ni, NiO, Pt/O-2/W, AgxBi(i-x), Bi2O3(s). The Gibbs energy of formation of solid Bi2O3 from pure elements was derived: ΔG0f(α-Bi2O3) = -598 148 + 309.27T [J mol-1] and ΔG0f(δ-Bi2O3) = -548009 + 258.94T [J . mol-1]; the temperature and the heat of the α → 8 transformation for this solid oxide were calculated as 996 K and 50.14 J . mol-1. Activities of Bi in the liquid alloys were determined in the temperature range from 860-1075 K, for five Ag-Bi alloys (XAg = 0.2, 0.35, 0.5, 0.65, 0.8), and a Redlich-Kister polynomial expansion was used to describe the thermodynamic properties of the liquid phase. Using Thermo-Calc software, the Ag-Bi phase diagram was calculated. Finally, thermodynamic data were used to predict surface tension behavior in the Ag-Bi binary system.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Structure des liquides et des solides; cristallographie, Structure of solids and liquids; crystallography, Nanomatériaux : agrégats, nanoparticules, nanotubes et nanocristaux, Nanoscale materials: clusters, nanoparticles, nanotubes, and nanocrystals, Clusters, nanoparticles, and nanocrystalline materials, Agrégat atomique, Atomic clusters, Algorithme génétique, Genetic algorithms, Approximation liaison forte, Tight binding approximation, Etude théorique, Theoretical study, Hydrogénation, Hydrogenation, Propriété thermodynamique, Thermodynamic properties, Silane, Silanes, Structure cristalline, Crystal structure, Structure géométrique, Geometrical structure, and Estructura geométrica

Energy minimization studies were carried out for a number of hydrogenated silicon clusters of the type SinH2m using a Tight-Binding model coupled with the biologically inspired optimizer, genetic algorithms (GAs). The results are compared with a previously published report on these clusters where the ground state geometry optimizations were not carried out. The optimized results fully resolved the cluster configurations in three dimensions, which are often different from the un-optimized configurations reported earlier.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Diagrammes de phases des métaux et alliages, Phase diagrams of metals and alloys, Article synthèse, Reviews, Diagramme phase, Phase diagrams, Equilibre phase, Phase equilibria, Système quasi binaire, Quasi-binary systems, Système ternaire, Ternary systems, Sélénium, Selenium, Tellure, Tellurium, Thallium, and Système Se Te Tl

The phase diagram for the system Tl2Te-Tl2Se has been determined on the basis of the results of studies by means of common thermal analysis. The diagram has been compared with diagrams published earlier. Some regularities have been presented for the quasi-binary chalcogenide systems with common cation.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Diagrammes de phases des métaux et alliages, Phase diagrams of metals and alloys, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Bore, Boron, Diagramme phase, Phase diagrams, Diffraction RX, XRD, Equilibre phase, Phase equilibria, Etude expérimentale, Experimental study, Microscopie électronique balayage, Scanning electron microscopy, Niobium, Structure cristalline, Crystal structure, Système binaire, Binary systems, and Sytsème B Nb

The currently accepted Nb-B phase diagram shows Nbss (solid solution), Nb3B2, NbB, Nb5B6, Nb3B4, NbB2, B, and liquid L as the stable phases in this system. There is a general agreement in the literature about the stability of the NbB, Nb3B4, and NbB2 phases. However, the stability of Nb3B2, Nb5B6, and Nb2B3 phases is arguable. The aim of this work was to reevaluate the phase equilibria in the Nb-rich region (0-50at.%B) of the Nb-B system. The alloys were arc melted from high purity materials and heat-treated at 1700 °C under high vacuum. The samples were characterized by scanning electron microscopy / back-scattered electron image (SEM/BSE) and x-ray diffraction (XRD). The most important findings were: (1) no liquid formation was observed during heat-treatments of the alloys at 1700 °C; (2) the eutectic reaction in the Nb-rich region is L ↔ Nbss+ NbB with liquid eutectic composition close to 16 at.%B; and (3) the Nb3B2-phase is formed through the peritectoid reaction Nbss+ NbB ↔ Nb3B2. These results support the phase diagram proposed by Rudy [1969 Rud] for the Nb-rich region, which is not in agreement with the currently accepted Nb-B phase diagram.