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1.
The phase diagram for the system LiClCaCl2CaCrO4 has been studied using differential thermal analysis. LiClCaCl2CaCrO4 has been shown by X-ray diffraction to be a stable, diagonal section of the Li, Ca//Cl, CrO4 reciprocal ternary system. The three binary systems are: LiClCaCl2 which exhibits a double salt (LiCaCl3), which decomposes without melting at 439°C and a eutectic at 36.3 mole % CaCl2 (m.p. 487°C); CaCl2CaCrO4 which shows a eutectic at 23.4 mole % CaCrO4 (m.p. 660°C); and LiClCaCrO4 with a eutectic at 14.3 mole % CaCrO4 (m.p. 538°C).In the ternary system, a eutectic exists at 63.2 mole % LiCl32.9% CaCl23.9% CaCrO4 (m.p. 479°C). In addition, a four-phase equilibrium, involving all solid phases, exists at nearly all compositions at 435°C.Isotherms are shown for the liquidus surface (primary crystallization) and for the secondary crystallization surface. Isothermal and vertical sections through the ternary phase diagram are shown.  相似文献   

2.
The Na2O-MgO-B2O3 system (500-550°C) and Rb2O-MgO-B2O3 system (550-700°C) were studied by the methods of powder X-ray diffraction and visual polythermal analysis, and their isothermal sections were constructed at 550 and 650-700°C, respectively. New ternary compounds were found to form: Na24Mg3B10O30, Na4Mg3B2O8, and Rb2Mg3B2O7.  相似文献   

3.
Phase equilibria and critical phenomena in the lithium nitrate-water-acetonitrile ternary system were studied by a visual polythermal method within the range of ?20 to 50°C. In this ternary system, the constituent liquid binary system is characterized by phase separation with an upper critical solution temperature. It was found that the ternary system undergoes phase separation at temperatures below 0.7°C. In the phase diagram within the range of ?1.1 to 0.7°C, a closed phase separation region with two critical points was revealed. The temperature of the formation of the critical tie line of the monotectic state the solid phase of which is the crystalline hydrate LiNO3 · 3H2O was determined (?18.7°C). Depending on the concentration, lithium nitrate has both salting-in and salting-out effect on aqueous acetonitrile mixtures. The plotted isothermal sections of the temperature-concentration prism of the system at fifteen temperatures showed the pattern of the topological transformation of its phase diagram with varying temperature.  相似文献   

4.
Phase relations in the MgO-Bi2O3-B2O3 system have been investigated by X-ray powder diffraction analysis and DTA. No ternary compounds have been found in the system. Quasi-binary sections have been the 600°C determined and isothermal section of the system has been constructed.  相似文献   

5.

Abstract  

Phase equilibria in the Au–Ge–Ni ternary system were studied by means of scanning electron microscopy, electron probe microanalysis, X-ray diffraction, and differential scanning calorimetry. The phase relations in the solid state at 600 °C as well as a vertical section at Au72Ge28–Ni were established. No ternary compound was found at 600 °C. On the basis of the experimental phase equilibria data, a thermodynamic model of the Au–Ge–Ni ternary system was developed using the CALPHAD method. Thermodynamically calculated phase diagrams are shown at 600 °C, in two vertical sections and the liquidus projection. Reasonable agreement between the calculations and the experimental results was achieved.  相似文献   

6.
The state diagrams (T-x) of the systems Ag2Te-ZnTe(I) and Ag2Te-Zn(II) are offered on the ground of data obtained by differential thermal analysis, X-ray phase analysis, microstructural analysis and measurements of the density and the microhardness of samples synthesized. The systems studied are quasibinary sections of the ternary system Ag-Zn-Te. System I is characterized by two eutectic and three eutectoidal non-variant equilibria as well as by an intermediate compound Ag2ZnTe2, which melts congruently at 880°C. The latter exists in the range from 120 to 880°C in two polymorphic modifications (Tʅ→β=515°C). System II is characterized by one eutectic, two eutectoidal and one peritectic nonvariant equilibria, boundary solid solutions on the ground of Ag2Te and Zn and one intermediate phase of the composition Ag4Zn3Te2, which melts congruently at 880°C.  相似文献   

7.
Phase equilibria in the BaO-Bi2O3-B2O3 system have been investigated by X-ray powder diffraction analysis and DTA. Quasi-binary sections have been determined, and an isothermal section of the system in the subsolidus region has been constructed. The BaO-Bi2O3-B2O3 ternary system has been divided into 22 triangles of coexisting phases. It has been found that four bismuth barium borates exist, namely, Ba3BiB3O9, BaBi2B4O10, BaBiB11O19, and BaBiBO4. Ba3BiB3O9 undergoes a phase transition at 850°C and exists up to 885°C, where it decomposes in the solid state. BaBiB11O19 and BaBi2B4O10 melt congruently at 807 and 730°C, respectively. BaBiBO4 melts incongruently at 780°C. X-ray powder diffraction data for the low-temperature polymorph of Ba3BiB3O9 are presented.  相似文献   

8.
Redetermination of the Phase Diagram TlI—SnI2 A reinvestigation of the phase diagram TlI—SnI2 revealed the existence of a not yet known ternary 4 : 1 compound of the formula Tl4SnI6, which decomposes peritectoidally at 229°C. The congruent melting points of the other three ternary compounds in the system, Tl3SnI5, TlSnI3, and TlSn2I5, at 329°C, 292°C and 307°C, respectively, agreed well with former specifications. However the polymorphic transitions of the compounds Tl3SnI5 and TlSn2I5 described by other authors could not be verified.  相似文献   

9.
The system TiC?HfC?WC was investigated by means of melting point, differential thermoanalytical, X-ray diffraction and metallographic techniques on hot pressed and heat treated as well as melted alloy specimens and a complete constitutional diagram from 1500°C through the melting range established. According to the peritectic melting of hexagonal WC both isopleths, TiC?WC as well as HfC?WC show a class II reaction at 2760°C in Ti?W?C and at 2730°C in Hf?W?C. The phase behaviour within the TiC?HfC?WC system is characterized by the presence of a (binary) miscibility gap within TiC?HfC [T c=1780°C, (TiC)0.55(HfC)0.45] which extends into the ternary forming a closed ternary miscibility gap at higher temperatures with an isolated ternary critical point:T c=1800°C, (TiC)0.55(HfC)0.45(WC)0.05. Interaction of the solvus (boundary of the cubic-B 1 monocarbide solid solution) and the ternary miscibility gap was established at 1540°C and (TiC)0.27(HfC)0.41(WC)0.32: Alloys of this composition enter a decomposition reaction on cooling into two isotypic cubic B 1 phases and hexagonal WC. Isothermal sections were calculated assuming regular solutions.  相似文献   

10.
Phase equilibria in the SrO-Bi2O3-B2O3 system were studied using powder X-ray diffraction (XRD) and differential thermal analysis (DTA). Quasi-binary sections were determined, and an isothermal section of the system in the subsolidus region at 600°C was constructed using the crossing spections method. A new ternary compound was found: SrBi2B4O10. The existence of SrBi2B2O7 was verified. Bi2O3-SrB2O4 and Bi4B2O9-2SrO: 3B2O3 polytherms were constructed.  相似文献   

11.
The title compound, obtained in the ternary system CuO2-P3O5-H2O at 160°C, crystallizes in the monoclinic crystal system (C2/c, Z=8).  相似文献   

12.
The formation of calcium hydroxide chlorides is an important issue in processes of the chemical raw materials industry, in terms of purification of flue gases, and concrete/cement corrosion. Current information on phase compositions given in the literature are contradictory. In this work systematic solubility studies were carried out at 25, 40, and 60 °C in the system Ca(OH)2‐CaCl2‐H2O and the compositions of the ternary solid phases were precisely determined using the Schreinemakers' method. Two ternary phases were identified, the hydrate 3Ca(OH)2 · CaCl2 · 12H2O and the anhydrous calcium hydroxide chloride Ca(OH)2 · CaCl2. The crystal structure of 3Ca(OH)2 · CaCl2 · 12H2O was solved by means of single‐crystal X‐ray diffraction at –123 °C (150 K).  相似文献   

13.
Investigations on the Pseudobinary System Bi2Se3/BiI3 The phase diagram of the pseudobinary system Bi2Se3/BiI3 was investigated by DTA, total pressure measurements and x-ray phase analysis. Only BiSeI exist as a ternary phase in this system. The compound melts incongruently at 545 °C. Heat of formation and standard entropy were calculated from vapor pressure data.ΔHB° (BiSeI, f, 298) = (–23.4 ± 1.9) kcal/mol S°(BiSeI, f, 298) = (38.7 ± 3.5) cal/K · mol  相似文献   

14.
The experimental investigations of phase equilibria in the K2SO4-KCl-H2O system at temperatures to 500°C and pressures to 100 MPa were directed to elucidate the phase transformation sequence that leads to the heterogenization of the supercritical fluid whose existence field propagates from the K2SO4-H2O binary subsystem to the ternary system. We suggest that fluid heterogenization in the title ternary system is accompanied by the transformation of the metastable immiscibility field to stable equilibria at elevated temperatures (near 460°C) and unexpectedly high pressures (~60 MPa), despite the presence of a vapor phase.  相似文献   

15.
Solubility of RbCl-Rb2SO4-H2O system at 25°C was predicted by using Pitzer ion-interaction model. The mixing parameter was was taken to be zero in the prediction. The calculated results indicated that the RbCl-Rb2SO4-H2O system is a simple eutonic ternary system at 25°C. This study will provide the theoretical basis for the extraction of rubidium from salt lake brines in Qinghai and Tibet Plateau.  相似文献   

16.
Phase relationships obtained by heating coprecipitated oxide powders in the HfO2Er2O3Ta2O5 system were investigated by X-ray diffractometry. Partial isothermal sections at 1100 and 1500°C are presented.  相似文献   

17.
Vapor-liquid equilibrium data are presented for the binary systems ethyl formate-methyl ethyl ketone (MEK) at 40°C and 50 °C and ethyl formate-toluene at 48°Cand 51°C and for the ternary system ethyl formate-MEK-toluene at 50°C. The measurements were carried out in a recirculation still similar to that proposed by Röck and Sieg. Vapor pressures of the pure substances were measured and the data correlated using the Antoine equation. The binary data were reduced by means of a maximum-likelihood procedure providing the relevant Margules, NRTL and UNIQUAC parameters.New UNIFAC interaction parameters between the groups ACH/HCOO, ACCH2/HCOO and CH2CO/HCOO have been obtained. These parameters have been used to predict the ternary data, and a comparison between the experimental and predicted values is presented.  相似文献   

18.
Phase equilibria in the Li, K‖Br, VO3 ternary mutual system were studied by differential thermal analysis. The composition square of the ternary mutual system is divided into two phase triangles, LiVO3-KBr-KVO3 and LiBr-LiVO3-KBr. The ternary eutectics E 1 at 331°C and E 2 at 330°C have the compositions 40.0 mol % LiVO3, 6.0 mol % KBr, 54.0 mol % KVO3 and 58.0 mol % LiBr, 3.2 mol % LiVO3, 38.8 mol % KBr, respectively. The fields of phases crystallizing in the system were delimited.  相似文献   

19.
The interaction in the HgBr2-CdBr2-PbBr2 ternary system was studied by differential thermal analysis; the isoconcentration section of the system at 50 mol % CdBr2 was investigated. Based on the results of the study, a projection of the liquidus surface of the HgBr2-CdBr2-PbBr2 ternary system to the composition triangle was constructed; the boundaries of the primary crystallization fields were determined for three phases: HgBr2 (degenerate field), solid solution α based on CdBr2, and solid solution β based on PbBr2; and isotherms were drawn. A ternary eutectic has the composition 93 mol % HgBr2-1 mol % CdBr2-6 mol % PbBr2 and melts at 235°C.  相似文献   

20.
The phase diagrams of the ternary reciprocal systems Na,K||BO2,CO3 and Na,K||BO2,Cl were studied for the first time by a calculation-experimental method and by differential thermal analysis. Analytical models of phase equilibrium states were derived, and the coordinates of eutectics were found to be (680°C, 32 mol % NaBO2, 68 mol % KCl) and (648°C, 9 mol % NaBO2, 45.5 mol % NaCl, 45.5 mol % KCl). Binary solid solutions based on metaborates and carbonates of sodium and potassium were shown to be stable. The possibility of synthesizing tungsten oxide bronzes in a eutectic melt in the ternary system NaBO2–NaCl–КCl was revealed.  相似文献   

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