Polythermal section Sn4P3-Sn4As3

The T-x diagram of the polythermal section Sn₄P₃-Sn₄As₃ of the Sn-P-As system was constructed using the results of X-ray powder diffraction and differential thermal analyses. A continuous series of solid solutions (Sn₄P₃) _x (Sn₄As₃)_{1 ? x} was found to exist. The section is not quasi-binary; in a Sn₄As₃-rich region, this section intersects the peritectic part of the three-phase volume (L + SnAs + α) of the ternary diagram.     

Phase equilibria in the Sn–As–Ge and Sn–As–P systems

T–x diagrams of polythermal GeAs–SnAs, GeAs–Sn₄As₃ sections of the Sn–As–Ge system and Sn₄P₃–Sn₄As₃ section of the Sn–As–P system were constructed using the results of X-ray powder diffraction and differential thermal analyses. It was found that the section GeAs–Sn₄As₃ is not quasi-binary due to realization of four-phase peritectic transformation L + SnAs ? GeAs + Sn₄As₃ at the temperature of 834 K. The quasi-binary section GeAs–SnAs represents a phase diagram of the eutectic type with the following coordinates of eutectic reaction: temperature of the eutectic point is 840 K, and composition is 20 mol% GeAs. In the Sn–As–P system, the existence of the solid-solution range indicated as (Sn₄As₃) _x (Sn₄P₃)_1?x  was defined. The polythermal section Sn₄P₃–Sn₄As₃ is not quasi-binary due to the fact that in the composition range with a high content of tin arsenide discussed section intersects the peritectic part of the three-phase volume (L + SnAs + α) of the ternary diagram.     

Interaction in the TlSe-Pr2Se3 system

The interaction of components in the TlSe-Pr₂Se₃ system was studied by differential thermal, X-ray powder diffraction, and microstructural analyses and also by microhardness and density measurements. The state diagram of this system was constructed. It was found that the section TlSe-Pr₂Se₃ is a quasi-binary section of the Tl-Pr-Se ternary system. In the TlSe-Pr₂Se₃ system at the component ratio 1: 1, a new chemical compound, TlPr₂Se₄, forms, which melts congruently at 1295°C. In the system based on TlSe, solid solutions form until 3.5 mol % Pr₂Se₃, and in the system based on Pr₂Se₃, solid solutions occur until 2.5 mol % TlSe.     

Phase equilibria and glass formation in the As2S3-TlAs2S2Se2 section of the As2S3-As2Se3-TlS system

Alloys in the As₂S₃-TlAs₂S₂Se₂ section of the As₂S₃-As₂Se₃-TlS ternary system were studied and a phase diagram was constructed using physicochemical methods (differential thermal analysis, microstructural analysis, X-ray powder diffraction, also microhardness and density measurements). The diagram in the As₂S₃-TlAs₂S₂Se₂ section is a non-quasi-binary diagonal section of the As₂S₃-As₂Se₃-TlSe quasi-ternary system. It was found that all the alloys in the section under ordinary conditions are obtained in the vitreous state. At low As₂S₃ concentrations in the section, solid solutions form up to 2.5 mol %, and at low TlAs₂S₂Se₂ concentrations, their extent is 3 mol %.     

The system YPO4Ca3(PO4)2Ca2P2O7

The ternary system YPO₄Ca₃(PO₄)₂Ca₂P₂O₇ has been investigated by differential thermal analysis, powder X-ray diffraction, and microscopy in reflected light. Its phase diagram and isothermal section at room temperature have been determined. The system contains only one double phosphate which is formed at the 1:1 molar ratio YPO₄:Ca₃(PO₄)₂, i.e., Ca₃Y(PO₄)₃.     

Phase equilibria in the InS-Sb2Te3 system

The interaction character of the InS-Sb₂Te₃ system was studied by differential thermal analysis, X-ray powder diffraction, microstructure examinations, microhardness measurements, and density determinations, and its phase diagram was constructed. The InS-Sb₂Te₃ phase diagram is a partially non-quasi-binary section of the In,Sb∥S,Te ternary reciprocal system. Two compounds are formed in the InS-Sb₂Te₃ system, namely: In₃Sb₂S₃Te₃ and InSb₂Te₃S. Sb₂Te₃-based solid solutions at room temperature have an extent of up to 6 mol % InS, while InS-based solid solutions are virtually nonexistent.     

Solid-Liquid Equilibria of the Ternary System Na+, Mg++ // Cl--H2O at 10°C

The isothermal section at 10°C of the solubility diagram of the ternary system Na+, Mg++// ClH₂O was established by conductimetric and analytical measurements. Two solid phases, NaCl and MgCl₂·6H₂O are observed. The solubility range of NaCl is large, while the liquidus curve of MgCl₂·6H₂O is very short. The composition of the eutonic point, determined by two methods was: 0.32 g% NaCl and 33.80 g% MgCl₂. This revised version was published online in July 2006 with corrections to the Cover Date.     

Phase equilibria in the iodine-potassium iodide-water-propanol-2 four-component system

Isothermal-isobaric sections of the phase diagram of the iodine-potassium iodide-water-propanol-2 (2-C₃H₇OH) four-component system were studied at 25°C and atmospheric pressure. In all sections, threephase eutonic equilibria were observed with potassium iodide and crystalline iodine as solid phases. Potassium iodide was a iodine salting in agent in sections containing 15 and 25 wt % propanol-2 and a salting out agent in the section with 50 wt % alcohol. H₂O-2-C₃H₇OH (85: 15 and 75: 25 wt %) mixed solvent compositions showed a higher ability to dissolve iodine than mixture components.     

Phase equilibria in the Tl-TlBr-S system

The polythermal sections TlBr-Tl₂S, TlBr-Tl₄S₃, TlBr-TlS, and Tl₆SBr₄-Tl; the isothermal section at 300 K of the phase diagram; and the projection of the liquidus surface of the Tl-S-Br system have been investigated in the composition region Tl-TlBr-S by DTA, X-ray powder diffraction analysis, and microhardness measurements. The primary crystallization regions, including that of the only ternary compound (Tl₆SBr₄), have been determined, and the types and coordinates of the invariant and univariant equilibria in the phase diagram are determined.     

Phase equilibria in the Tl-TlBr-Te system and thermodynamic properties of the compound Tl5Te2Br

The Tl-TlBr-Te composition region of the Tl-Te-Br phase diagram has been explored by DTA, X-ray diffraction, microhardness measurements, and electromotive force (emf) measurements relative to a thallium electrode in concentrations cells. The phase diagrams along a number of joins, the isothermal section at 400 K of the phase diagram, and a projection of the liquidus surface have been constructed. Extensive phase-separation areas, including a three-liquid-phase field in the Tl-TlBr-Tl₂Te subsystem, have been revealed. The homogeneity ranges and primary crystallization fields of phases have been mapped, and the coordinates of nonvariant and univariant equilibria in the T-x-y diagram have been determined. The standard thermodynamic functions of formation of the Tl₅Te₂Br compound and its standard entropy have been derived from emf data.     

Refining the Phase Diagram of the System 3Al2O3·2SiO2-ZrO2

The quasi-binary section mullite-zirconium dioxide in the ternary system Al₂O₃-SiO₂-ZrO₂, described by an eutectic phase diagram with T _{e u t} = 1750°C, was studied experimentally.     

Chemiluminescent ion-molecule reactions in the system C+ + H2

The optical emission resulting from collisions between C⁺ ions and H₂ gas was measured in the energy range 2 to 20 eV_c.m.. The observed spectrum consists mainly of the CH⁺ A ¹Π → X ¹Σ⁺ band system; CH⁺ (A ^fΠ) is shown to be formed in the chemiluminescent reactio: C⁺(²P⁰) + H₂ → CH⁺(A ¹Π) + H(²S). The energy dependence of the emission cross section was measured. The occurrence of this reaction is discussed in terms of a electronic state correlation diagram for the system.     

<Emphasis Type="Italic">Т–х</Emphasis> Diagram of Section BiB<Subscript>3</Subscript>O<Subscript>6</Subscript>–YbBO<Subscript>3</Subscript>

Phase equilibria were studied and a Т–х diagram of section BiB₃O₆–YbBO₃ was constructed using X-ray powder diffraction and differential thermal analysis (DTA). The diagram has a peritectic point lying near 95 mol % BiB₃O₆ at 810°С. A limited subsolidus solubility of the components is observed in α-BiB₃O₆ in the range 0 ≤ х ≤ 0.3 YbBO₃.     

Section EuNdGa3S7-EuGa4S7 of the ternary system Nd2S3-Ga2S3-EuS

The section EuNdGa₃S₇-EuGa₄S₇ of the ternary system Nd₂S₃-Ga₂S₃-EuS was studied by physicochemical analysis methods (differential thermal, X-ray powder diffraction, and microstructural analyses and microhardness and density measurements). The data obtained were used to construct the state diagram of the section EuNdGa₃S₇-EuGa₄S₇. The section was found to be a quasi-binary section of the ternary system and is of the eutectic type. The coordinates of the eutectic are 64 mol % EuGa₄S₇ and T _melt = 1170 K. A region of solid solutions based on both components was found.     

Phasengleichgewichte im System Tll-Pbl2

Phase Equilibria in the TlI? PbI₂ System The TlI? TlPbI₃ section of the quasibinary system TlI? PbI₂ was reinvestigated by thermoanalytical and X-ray methods in order to clear up a number of inconsistent data concerning the intermediate ternary phases and their stability regions. Differences between the resulting phase diagram and prior information in the literature are discussed.     

Phase diagram and local environment of Sn and Te: SnTeBi and SnTeBi2Te3 systems

From thermal analyses and X-ray diffraction the phase diagram of the BiSnTe and SnTeBi₂Te₃ sections was determined. The local environment of Sn and Te atoms was studied by ¹¹⁹Sn and ¹²⁵Te Mössbauer spectroscopy. The BiSnTe section showed a eutectic reaction at 267 °C and 20 % mole SnTe–80 % mole Bi. No intermediate compound was detected. The SnTeBi₂Te₃ section is characterized by a eutectic reaction at 585 °C and 40 % mole SnTe–60% mole Bi₂Te₃ and a peritectic reaction at 600 °C and 50 % mole SnTe–50% mole Bi₂Te₃. It corresponds to the compound SnBi₂Te₄, which has a rhombohedral layered structure with unit cell parameters a=4.3954(4) Å and c=41.606(1) Å. © 2000 Académie des sciences / Éditions scientifiques et médicales Elsevier SASSnTe / Bi / Bi₂Te₃ / phase diagram / Mössbauer     

Representation T-V-X d'une monotexie dans les systemes binaires a tension de vapeur non negligeable

Binary systems with non-negligible vapour pressure in which a monotectic equilibrium takes place are described in aT-V-x diagram. Two kinds of equilibrium may occur, which correspond to the following reactions:S+L ₁ ? L ₂+V, andS+L ₁ +V?L ₂, when the temperature rises. The first generates a quadrilateral monotectic invariant. The second generates a triangular monotectic invariant. These two invariants are described in theT-V-x diagram and discussed.     

Phase Relationships in the Section CaGeO3-BaSiO3 of the Ternary Mutual System CaO, BaO∥SiO2, GeO2

Phase relationships in the section CaGeO₃-BaSiO₃ in the range 1000-1500°C were studied. Samples were prepared by a solid-phase procedure. The phase relationships were studied by X-ray phase, differential thermal, and crystal-optical (with immersion specimens) analyses and by the annealing-quenching technique. The phase diagram of the system CaGeO₃-BaSiO₃ was constructred. A discrete variable-composition berthollide phase crystallizing in the walstromite structural type was revealed. No solid solutions based on the extreme members of the system were found. The diagram of phase equilibria in the edge sections of the concentration tetragon CaSiO₃-4CaGeO₃-BaGeO₃-BaSiO₃ is presented, and the solubility boundaries are schematically shown for the solid solutions existing in this system at 1200°C.     

Phase equilibria in the neodymium-barium-copper-oxygen system at low oxygen pressures

The analytic equations for the Gibbs energies of Nd-Ba-Cu-O system phases obtained earlier were used to calculate the (1/2)BaCuO₂-(1/2)NdCuO₂ section of the phase diagram at oxygen partial pressures of 0.01 and 0.001 bar. For p(O₂) = 0.01 bar, the coordinates of the nonvariant points of the Nd-Ba-Cu-O system were determined, and the phase diagrams of the (1/8)Ba₃Cu₅O₈-NdO_1.5 and (1/4)BaCu₃O₄-(1/4)BaNd₃O_5.5 systems were calculated.     

Chemischer Transport ternärer Indiummolybdate

Chemical Vapor Transport of Ternary Indium Molybdates An isothermal section of the phase diagram of the system In/Mo/O at 1273 K was established by isothermal equilibration and XRD analyses of quenched samples. The chemical vapor transport of In₂Mo₃O₁₂ was investigated in dependence on mean transport temperature (823 K to 1123 K) and amount of transport agent (Cl₂ or Br₂). The observed transport behaviour is compared with results of thermodynamical calculations and the influence of mean temperature, transport agent and moisture contents is described in detail. Single crystals of the metal rich compound InMo₄O₆ were grown by chemical vapor transport in a temperature gradient 1273 K to 1173 K using H₂O as transport agent. The gaseous compound In₂MoO₄(g) accounts for the chemical vapor transport of molybdenium compounds in the metal rich part of the ternary phase diagram In/Mo/O.