THE PHASE DIAGRAM OF THE SYSTEM Na3AlF6–Na2SO4 AND THE DISSOCIATION OF THE CRYOLITE ANION IN MOLTEN SODIUM SULPHATE

1959 ◽  
Vol 37 (7) ◽  
pp. 1170-1175 ◽  
Author(s):  
Kai Grjotheim ◽  
Tor Halvorsen ◽  
Sigmund Urnes
Keyword(s):  
Thermal Analysis ◽  
Phase Diagram ◽  
Solid Solution ◽  
Binary System ◽  
Freezing Point ◽  
Eutectic Point ◽  
Sodium Sulphate ◽  
Freezing Point Depression ◽  
Molten Sodium

The binary system Na3AlF6–Na2SO4 has been investigated. A eutectic point was found at 91 mole % Na2SO4. On the Na3AlF6 side of the diagram extensive solid solution was found. No solid solution was observed on the Na2SO4 side, either by thermal analysis or by Debye–Scherrer diagrams. The freezing point depression of Na2SO4 caused by additions of Na3AlF6 has been used to evaluate the dissociation scheme of the cryolite anion in a sodium sulphate melt. The calculations favor the following scheme:AlF63− = AlF4− + 2F−.

Phase Relationships in the Calcium Chloride – Calcium Carbide System

1972 ◽  
Vol 50 (6) ◽  
pp. 839-843 ◽  
Author(s):  
J. F. Maillot ◽  
D. R. Morris
Keyword(s):  
Thermal Analysis ◽  
Melting Point ◽  
Calcium Chloride ◽  
Freezing Point ◽  
Eutectic Point ◽  
Calcium Carbide ◽  
Carbide System ◽  
Phase Relationships

The system calcium chloride – calcium carbide has been examined by thermal analysis. The depression of the freezing point of CaCl2 by CaC2 is ideal. The system is a eutectic one, with a eutectic point at 90 mol% CaCl2 at 740 °C. Carbon is believed to be present in the electrolyte as the so called acetylide ion [Formula: see text] The melting point of pure CaCl2 was found to be 775.2 ± 0.6 °C.

Revised phase diagram for the Nd–Pt system from 35 to 85 at% platinum

2010 ◽  
Vol 43 (1) ◽  
pp. 33-37 ◽  
Author(s):  
Ch. F. Xu ◽  
Z. F. Gu ◽  
G. Cheng ◽  
H. Y. Zhou ◽  
Z. M. Wang ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Phase Diagram ◽  
Differential Thermal Analysis ◽  
Binary System ◽  
Homogeneity Range ◽  
Low Temperatures ◽  
Polymorphic Transformation ◽  
Structure Type ◽  
X Ray Diffraction ◽  
X Ray

The phase diagram of the Nd–Pt system from 35 to 85 at%Pt has been revised using X-ray diffraction and differential thermal analysis. It is found that the Nd3Pt4phase with the rhombohedral Pd4Pu3structure type is unstable and decomposes into the two neighboring phases NdPt and NdPt2at temperatures ranging approximately from 583 to 1123 K. It is confirmed that the homogeneity range for the Laves phase NdPt2extends from about 68.5 to 75.3 at%Pt in the Nd–Pt binary system. The polymorphic transformation temperature of α-NdPt ⇌ β-NdPt is about 623 K, where the α-NdPt phase with BFe type is stable at low temperatures and the β-NdPt phase with BCr type at high temperatures.

Equilibrium phases in the BeSO4-H2O system

1966 ◽  
Vol 19 (5) ◽  
pp. 751 ◽  
Author(s):  
IJ Bear ◽  
AG Turnbull
Keyword(s):  
Thermal Analysis ◽  
Phase Diagram ◽  
Solid Solution ◽  
Differential Thermal Analysis ◽  
Infrared Spectra ◽  
Kcal Mole ◽  
X Ray ◽  
Reversible Transitions ◽  
Equilibrium Phases

The equilibrium phases of the BeSO4-H2O system were studied by vapour hydration of BeSO4 and equilibration of thermally produced mixtures. Tetra-, di-, and mono-hydrate are the stable hydrates with no solid solution regions between them. X-ray and infrared spectra are presented for these hydrates and a provisional phase diagram drawn.��� Reversible transitions of BeS04 were found at 588° and 639°, the latter showing a hysteresis splitting of 4° on cooling. Transition heats of 1.2 ± 0.1 and 0.5 ± 0.1 kcal/mole respectively were found by differential thermal analysis.

scholarly journals Solid-Liquid Phase Diagram of the Binary System Octadecanoic Acid and Octadecanol and the Thermal Chemical Property of the Composition at Eutectic Point

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Can Liu ◽  
Kaiyu Zhao ◽  
Yafei Guo ◽  
Liping Guo ◽  
Tianlong Deng
Keyword(s):  
Phase Diagram ◽  
Liquid Phase ◽  
Binary System ◽  
Phase Change ◽  
Mass Fraction ◽  
Eutectic Point ◽  
Octadecanoic Acid ◽  
Phase Change Temperature ◽  
Change Temperature ◽  
Solid Liquid

Phase diagram is a powerful tool to guide the exploitation of thermal energy materials. Heat storage technology of phase-change material (PCM) was widely used to solve major energy utilization problems on large energy consumption and low utilization efficiency. In this work, a novel solid-liquid phase diagram of the binary system octadecanoic acid (C18-acid) + octadecanol (C18-OH) was investigated using the differential scanning calorimeter (DSC). The phase-change temperature and phase-change enthalpies against the composition of C18-acid and C18-OH were determined experimentally, and then the binary phase diagram of T–X (X expresses the mass fraction of C18-OH in the two components of C18-acid and C18-OH) was established for the first time. The phase diagram belongs to a binary simple system with one eutectic point, and the content of C18-OH at eutectic point is 0.4 in mass fraction. Neither solid solution nor copolymer was formed. The thermal chemical properties on the phase-change latent heat (Q), phase-change temperature (Tp), and the thermal conductivity (λ) for the composition at the eutectic point of the binary system are 198.7 J·g−1, 44.2°C, and 0.2352 W·m−1·K−1, respectively. This result indicates that the material at eutectic point has a great potential to be used as energy storage material for supply of heat and scouring bath.

scholarly journals Phase Diagram, Caesium-133 NMR Spectra and Electrical Conductivity of the Binary System Caesium and Zinc Butyrates

2000 ◽  
Vol 55 (11-12) ◽  
pp. 895-898
Author(s):  
T. A. Mirnaya ◽  
V. V. Trachevski ◽  
V. S. Dradrakh ◽  
D. V. Bylina
Keyword(s):  
Thermal Analysis ◽  
Phase Diagram ◽  
Electrical Conductivity ◽  
Differential Thermal Analysis ◽  
Binary System ◽  
Nmr Spectra ◽  
Composition Range ◽  
Specific Electrical Conductivity ◽  
Polarization Microscopy ◽  
Smectic Liquid Crystals

Abstract Phase equilibria of non-mesogenic caesium- and zinc-butyrate mixtures were studied by differential thermal analysis and hot stage polarization microscopy. Smectic liquid crystals were found in some composition range. Their appearance is explained by the latent mesomorphism of caesium butyrate. |133Cs NMR spectra and the specific electrical conductivity of the molten mixtures at 155°C were employed to investigate the peculiarities of ionic association and interaction in the melts.

PHASE EQUILIBRIUM IN THE AS2TE3-TM2TE3 SYSTEM.

2020 ◽  
Vol 5 (8(77)) ◽  
pp. 65-68
Author(s):  
Teymur Mammad Ilyasly ◽  
Rahman Hasanaga Fatullazade ◽  
Zakir Islam Ismailov ◽  
Nigar Nadir Jafarova
Keyword(s):  
Thermal Analysis ◽  
Solid Solution ◽  
Differential Thermal Analysis ◽  
Phase Equilibrium ◽  
Physicochemical Properties ◽  
Thermal Effects ◽  
Isothermal Annealing ◽  
Intermediate Phase ◽  
Physicochemical Analysis ◽  
Two Phases

The synthesis of alloys of the system was carried out stepwise in rotary furnaces. The synthesis mode was selected based on the physicochemical properties of the elementary components. For homogenization, the alloys were subjected to isothermal annealing at 750 and 1275 K, depending on the Tm2Te3 concentration, for 250 h after homogenization of the alloys, they were subjected to physicochemical analysis. The results of differential thermal analysis showed that reversible thermal effects are observed in the alloys of the system. In alloys in a 1: 1 ratio, a new intermediate phase is formed with a composition corresponding to the TmAsTe3 compound. The homogeneity area is observed in the concentration range 52.5-47.5. It was found that in the concentration range 98.5-52.5 Tm2Te3 there are two phases - a mixture of β and of the solid solution, and in the concentration range of 47.51 mol% Tm2Te3 phases and α are in equilibrium. ) 66 The eutectic has coordinates of 11.5 mol Tm2Te3 at a temperature of 575 K.

Sign in / Sign up

Export Citation Format

Share Document