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The phase separation of protein and RNA mixtures underpins the assembly and regulation of numerous membraneless organelles in cells. The ubiquity of protein–RNA condensates in cellular regulatory processes is in part due to their sensitivity to RNA concentration, which affects their physical properties and stability. Recent experiments with poly-cationic peptide–RNA mixtures have revealed closed-loop phase diagrams featuring lower and upper critical solution temperatures. These diagrams indicate reentrant phase transitions shaped by biomolecular interactions and entropic forces such as solvent and ion reorganization. We employed atomistic simulations to study mixtures with various RNA–polylysine stoichiometries and temperatures to elucidate the microscopic driving forces behind reentrant phase transitions in protein–RNA mixtures. Our findings reveal an intricate interplay between hydration, ion condensation, and specific RNA–polylysine hydrogen bonding, resulting in distinct stoichiometry-dependent phase equilibria governing stabilities and structures of the condensate phase. Our simulations show that reentrant transitions are accompanied by desolvation around the phosphate groups of RNA, with increased contacts between phosphate and lysine side chains. In RNA-rich systems at lower temperatures, RNA molecules can form an extensive pi-stacking and hydrogen bond network, leading to percolation. In protein-rich systems, no such percolation-induced transitions are observed. Furthermore, we assessed the performance of three prominent water force fields—Optimal Point Charge (OPC), TIP4P-2005, and TIP4P-D—in capturing reentrant phase transitions. OPC provided a superior balance of interactions, enabling effective capture of reentrant transitions and accurate characterization of changes in solvent reorganization. This study offers atomistic insights into the nature of reentrant phase transitions using simple model peptide and nucleotide mixtures. We believe that our results are broadly applicable to larger classes of peptide–RNA mixtures exhibiting reentrant phase transitions. [ABSTRACT FROM AUTHOR]

The system BaO–TiO2 is technically important because it contains multiple dielectric and ferroelectric phases, including the important BaTiO3, which is one of the most widely studied dielectric perovskites owing to its dual piezoelectric and ferroelectric properties. The present work revises the subsolidus phase equilibria data by synthesizing previous phase equilibria data and new experimental results using high‐temperature (600°–1300°C) and long‐term (≤336 h) equilibration, coupled with analytical work based principally on room‐temperature X‐ray diffraction. The resultant phase diagram is given in both mole and weight percents, extending from the liquidus surface (not investigated) to absolute zero temperature (for inclusion of the previously excluded crystallographic and ferroelectric phase transformations). The major features include (1) correction of four eutectoid and three peritectoid reactions and corresponding temperatures, (2) indication of inferred partial solid solubilities, (3) clarification of the BaTiO3 solid solubility homogeneity regions, and (4) specification of some invariant point compositions on the liquidus surface. [ABSTRACT FROM AUTHOR]

Despite its importance, the Ag-Cu-Te system's phase diagram remains poorly understood. This study addresses this gap by investigating the equilibrium phases in equilibrated Ag-Cu-Te alloys. Combining these experimental results with existing literature and the phase diagrams of the Ag-Cu, Ag-Te, and Cu-Te binary systems, the isothermal sections of the Ag-Cu-Te ternary phase equilibria at 600 °C and 400 °C are proposed. The phase diagrams of the binary systems, Ag-Te and Cu-Te, were reassessed. In the Ag-Te binary system, there are three compounds, Ag2Te, Ag1.9Te, and Ag5Te3. There are three binary compounds, Cu2Te, Cu3Te2, and CuTe, in the binary Cu-Te system. Ag and Cu whiskers were discovered along the Cu-Cu2Te-Ag2Te-Ag section, which prevented the determination of phase equilibria results in this region. One ternary compound, AgCuTe, was identified in the system. There are six and nine three-phase regions at 600 °C and 400 °C, respectively. There are limited Ag solubilities in the Cu3Te2 and CuTe phases. [ABSTRACT FROM AUTHOR]

The system BaO–TiO2 is technically important because it contains multiple dielectric and ferroelectric phases, including the important BaTiO3, which is one of the most widely studied dielectric perovskites owing to its dual piezoelectric and ferroelectric properties. The present work revises the subsolidus phase equilibria data by synthesizing previous phase equilibria data and new experimental results using high‐temperature (600°–1300°C) and long‐term (≤336 h) equilibration, coupled with analytical work based principally on room‐temperature X‐ray diffraction. The resultant phase diagram is given in both mole and weight percents, extending from the liquidus surface (not investigated) to absolute zero temperature (for inclusion of the previously excluded crystallographic and ferroelectric phase transformations). The major features include (1) correction of four eutectoid and three peritectoid reactions and corresponding temperatures, (2) indication of inferred partial solid solubilities, (3) clarification of the BaTiO3 solid solubility homogeneity regions, and (4) specification of some invariant point compositions on the liquidus surface. [ABSTRACT FROM AUTHOR]

The phase equilibria information of the CaO–SbOx system in the range of 700–1580°C in air was obtained for the first time using quenching method and thermal analysis. The equilibrium phase compositions were determined using x‐ray diffraction and Scanning Electron Microscopy‐Energy Dispersion Spectrum. The invariant reaction temperatures were determined using thermogravimetry‐differential scanning calorimetry. A perovskite solid solution between Ca2Sb2O7 and CaO, designated as (Ca6Sb2O11)s.s, was observed. Within this solid solution, three polymorphic forms were identified: orthorhombic, tetragonal, and cubic. The transition temperatures between these polymorphic forms vary with compositional changes. Additionally, the crystal structure of cubic Ca6Sb2O11 was analyzed. CaSb2O6 was observed to decompose into Ca2Sb2O7, Sb4O6, and O2 above 1336 ± 5°C. The eutectic temperature of α‐Sb2O4 and CaSb2O6 was found to be 1220 ± 5°C. [ABSTRACT FROM AUTHOR]

BiFeO3 and EuFeO3 are some of the most studied ferrites and part of the larger category of multiferroic and magnetic compounds. The instabilities reported for BiFeO3 that hinder its use in practical applications can be overcome by substitution with rare-earth ions, such as Eu3+, on the Bi3+ site. This paper reports on the phase relations in the BiFeO3-EuFeO3 pseudo-binary system, which were not established previously. Solid-state reactions were employed to prepare different compositions according to the nominal formula Bi1−xEuxFeO3 (where x = 0, 0.05, 0.10, 0.15, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and 1). Phase equilibria were studied at different temperatures between 800 and 1200 °C from X-ray diffraction (XRD) data. The analysis of the XRD patterns by machine learning approaches revealed eight defined clusters and four unclustered points. The validation test showed that most of the points could belong to several clusters and thus, traditional identification was employed. Phase identification and quantification by traditional approaches revealed six crystallization zones on the diagram. Although the machine learning approach offers speed in the process of classification of XRD patterns, validation by the traditional method was necessary for the construction of the phase diagram with high accuracy. [ABSTRACT FROM AUTHOR]

During his time at Royal Institute of Technology (Kungliga Tekniska högskolan) in Sweden, the present author learned nonequilibrium thermodynamics from Mats Hillert. The key concepts are the separation of internal and external variables of a system and the definitions of potentials and molar quantities. In equilibrium thermodynamics derived by Gibbs, the internal variables are not independent and can be fully evaluated from given external variables. While irreversible thermodynamics led by Onsager focuses on internal variables though often mixed with external variables. Hillert integrated them together by first emphasizing their differences and then examining their connections. His philosophy was reflected by the title of his book "Phase Equilibria, Phase Diagrams and Phase Transformations" that puts equilibrium, nonequilibrium, and internal processes on equal footing. In the present paper honoring Hillert, the present author reflects his experiences with Hillert and his work in last 40 years and expresses his gratitude for all the wisdom and support from him in terms of "Hillert nonequilibrium thermodynamics" and discusses some recent topics that the present author has been working on. [ABSTRACT FROM AUTHOR]

The method of constrained equilibria has already found extensive use for a good number of years in conjunction with the programmers library ChemApp and freely adaptable ASCII based thermodynamic datafiles. In the present paper a method is demonstrated which permits the application of this method in the framework of the Integrated Thermodynamic Databank System (ITDS) FactSage. Both, modules which interact with the databases and modules which carry out thermodynamic calculations are used, thus emphasizing the aspect of integration in the ITDS. In the paper a link will be established between original thoughts by J.W. Gibbs concerning the definition of the components of a system and kinetic inhibitions in the system and the method of constrained equilibria as such. Furthermore, reference is made to Mats Hillerts use of driving forces in complex (non-)equilibrium cases. A number of application cases with different degrees of complexity will be demonstrated. These range from partially or fully constrained complex equilibrium calculations to phase diagrams with new types of axis variables. [ABSTRACT FROM AUTHOR]

The K2O‐Al2O3‐SiO2 system is an important component of microcrystalline glass. The K2O‐Al2O3 and K2O‐SiO2 binary systems and the K2O‐Al2O3‐SiO2 ternary system were thermodynamically evaluated and optimized using the CALculation of PHAse Diagram (CALPHAD) method. The liquid phase is described by using the ionic two‐sublattice model, and the solid solutions involved in the ternary system are all described using the compound energy formalism (CEF) model. The new parameters obtained from the optimization are capable of describing the equilibrium phase relations of the ternary system and its subsystems, and the calculated thermodynamic properties of the ternary compounds are in good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

Knowledge of the thermodynamic equilibria and domain structures of ferroelectrics is critical to establishing their structure–property relationships that underpin their applications from piezoelectric devices to nonlinear optics. Here, we establish the strain condition for strain phase separation and polydomain formation and analytically predict the corresponding domain volume fractions and wall orientations of, relatively low symmetry and theoretically more challenging, monoclinic ferroelectric thin films by integrating thermodynamics of ferroelectrics, strain phase equilibria theory, microelasticity, and phase‐field method. Using monoclinic KxNa1 − xNbO3(0.5 < x < 1.0) thin films as a model system, we establish the polydomain strain–strain phase diagrams, from which we identify two types of monoclinic polydomain structures. The analytically predicted strain conditions of formation, domain volume fractions, and domain wall orientations for the two polydomain structures are consistent with phase‐field simulations and in good agreement with experimental results in the literature. The present study demonstrates a general, powerful analytical theoretical framework to predict the strain phase equilibria and domain wall orientations of polydomain structures applicable to both high‐ and low‐symmetry ferroelectrics and provide fundamental insights into the equilibrium domain structures of ferroelectric KxNa1 − xNbO3 thin films that are of technology relevance for lead‐free dielectric and piezoelectric applications. [ABSTRACT FROM AUTHOR]

As advances are being made regarding the performance of nuclear fuels, uranium carbides, and composites, such as (U,Zr)C and UO 2 + UC x , have recently gained significant interest for deployment in nuclear space propulsion and high temperature gas-cooled reactors, respectively. However, the phase equilibria of several fission products in carbide systems remain unknown and may impact the overall fuel performance, specifically for particle nuclear fuels that are designed for commercial nuclear energy. Furthermore, comprehensive thermodynamic data on Rare Earth (RE) carbides, such as the Nd-C and Ce-C binary systems, remain limited. Presented in this study are the synthesis methods and characterizations of several Nd-C and Ce-C compositions. The findings from this research provide insights on the stability of RE-C binaries that form in irradiated nuclear fuels and address a critical knowledge gap in the current state of thermodynamics for two key RE-C systems. [ABSTRACT FROM AUTHOR]

Copyright of Nonferrous Metals (Extractive Metallurgy) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Refractory superalloys (RSAs) are promising candidates for high-temperature, high-strength applications. Two-phase RSAs containing body-centered cubic (BCC) and ordered B2 phases are among the more promising candidates. Systems containing Ru-based B2 precipitates exhibit stable two-phase microstructures at temperatures in excess of 1600 °C. The present study experimentally investigated one potential foundational ternary system for these alloys, Nb-Ti-Ru. Two alloys, (Nb3Ti)0.85Ru0.15 and (Nb4Ti)0.85Ru0.15, were studied to determine phase equilibria and properties at temperatures between 900 °C and 1300 °C. The B2 phase was found to be dominated by RuTi ordering, although considerable Nb solubility was observed up to 18 mol %. The Nb-rich BCC matrix contained up to 15 mol % Ru and 20 mol % Ti. Although a two-phase microstructure of B2 precipitates in a BCC matrix was confirmed, the distribution of elements in the two phases resulted in a larger lattice misfit than expected. The results obtained in this investigation provide valuable information for the future development of RSAs utilizing Ru-based B2 strengthening precipitates. [ABSTRACT FROM AUTHOR]

Levulinic acid (LA), a carboxylic acid with a keto-acid structure, has recently been gaining increasing attention as a promising biorefinery platform chemical due to its potential to be feasible and sustainable. This work focuses on using trioctylamine (TOA) to separate LA from an aqueous solution by liquid–liquid extraction. For that, binodal curves and tie lines were determined at T = (293.15, 313.15, and 333.15) K under atmospheric pressure. The slope of the determined tie lines demonstrates that higher extraction efficiencies are possible with higher acid concentrations. Furthermore, infrared spectroscopy (FT-IR) was applied to better understand the behavior of phase diagrams. This study detected the acid-extractant complex formation between (LA) and (TOA). Finally, the experimental data were successfully correlated with the NRTL model at all the measured temperatures. The obtained parameters were applied using a decanter model. [ABSTRACT FROM AUTHOR]

This report is the first analysis of the coexistence and microstructure of the equilibrium phases in the Fe-Pd L10 + L12 eutectoid region. Coexistence of L10 + L12 is observed at higher temperatures (650 ∘ C ), resulting in L10 polytwin plates with internal boundaries that are decorated by L12. For higher Pd content, the L10 plates are embedded in an extended L12 matrix, but the L12 wetting layers still persist. For aging at low temperatures (525 ∘ C ), L1' + L12 coexistence is observed, but the microstructure is essentially similar, except that L10 is replaced by L1'. The two-phase region is found to be much narrower than reported in published phase diagrams, of order 0.6 to 1 at pct in extent. There may be a further re-entrant narrowing below the L1' formation temperature. This work establishes L1' as a phase distinguishable from both L10 and L12, but does not yet prove that L1' is an equilibrium phase. The preferred formation of L1' at lower temperatures may relate both to stability conferred by overall ferrimagnetic interactions, and perhaps by kinetics, where L1' should have a reduced nucleation barrier from A1 relative to L10. [ABSTRACT FROM AUTHOR]

This paper presents equations derived from thermodynamic equations for calculating the liquidus and solidus temperatures, the liquidus slope, and the partition ratio for solidification simulations. The constants of these equations can be easily determined from measurement data obtained by digitalisation from known diagrams or can be calculated using a CALPHAD-based software. ESTPHAD has a hierarchical system; the developed functions of the binary systems are used in the calculation of the functions of the ternary systems, the functions of the ternary systems in the calculation of the function of quaternary systems, and so on. The developed method is demonstrated by processing the liquidus and solidus of Si–Ge isomorphous and Al–Mg and Al–Si eutectic equilibrium phase diagrams. The use of this method for calculating the functions of ternary systems will be shown in Part II. The advantages of this method are that the equations are simple, can be determined very quickly, and can be built into the simulation software very easily. The most significant advantage is that the calculation time is shorter by some order of magnitude than that of a CALPHAD-type calculation. [ABSTRACT FROM AUTHOR]

Phase equilibria in the ZrO2–YO1.5–NbO2.5 system were experimentally studied at 1300°C, and a comparison with the existing ZrO2–YO1.5–TaO2.5 (ZYTO) was conducted. Ternary fluorite phases on the Y:Nb > 1 side extend from binary ZrO2‐YO1.5 to YO1.5–NbO2.5 system, generating a continuous solid solution region. Furthermore, it was observed that three phases of M‐YNbO4, fluorite, and m‐ZrO2 were in equilibrium. On the Y:Nb < 1 side, two three‐phase equilibrium regions were measured, namely M‐YNbO4+m‐ZrO2+O‐Nb2Zr6O17 and h‐Nb2O5+O‐Nb2Zr6O17+M‐YNbO4. The tetragonal YNbO4 and ZrO2 phases both extend nearly along with Y:Nb = 1. The t‐ZrO2 phases with slightly lower stabilizer content were found to transform into their monoclinic polymorph during the cooling process. However, in the ZrO2–YNbO4 subsystem, the tetragonal ZrO2 was nontransformable due to larger YO1.5 and NbO2.5 co‐dopants, and the maximum solubility is about 18.1 mol%. Upon cooling, the tetragonal YNbO4 phase, even with the maximum ZrO2 content, is transformable to monoclinic form. The maximum solubility of ZrO2 in YNbO4 is determined to be about 20.7 mol%. Finally, the high‐temperature liquidus in the ZrO2–YNbO4 system was first determined based on the cooling traces, and a vertical section diagram was proposed for further speculation. A eutectic reaction of Liquid→YNbO4+ZrO2 was discovered, and the eutectic composition and temperature were measured as 39.2ZrO2–29.2YO1.5–31.6NbO2.5 and 1813°C. This study provides the basis for thermodynamic assessment of ZrO2–YO1.5–NbO2.5 and is valuable for the design and development of the ZrO2–YO1.5–NbO2.5‐based ceramic materials. [ABSTRACT FROM AUTHOR]

The phase diagram of the CaO-SiO2-Nb2O5-Fe2O3-TiO2 slag system has important significance for guiding the recycling and utilization processes of metallurgical slags containing niobium and titanium. In this paper, high-temperature equilibrium experiments were conducted at 1100 °C in air atmosphere to investigate the phase equilibria of the CaO-SiO2-Nb2O5-Fe2O3-TiO2 slag system. According to the experimental results, the liquidus surfaces of the liquid + CaTiO3 and liquid + SiO2 equilibrium coexistence regions in the CaO-SiO2-Nb2O5-5wt.% Fe2O3-TiO2 system at 1100 °C in air atmosphere were determined using interpolation and function fitting methods. Finally, the 1100 °C isothermal phase diagrams of the CaO-SiO2-Nb2O5-5 wt.% Fe2O3-TiO2 system were plotted. The composition range of liquid phase region was determined, and the positional relationships of the seven other equilibrium coexistence regions were illustrated. [ABSTRACT FROM AUTHOR]

The effects on phase equilibria of La and Fe additions to the Al–Ce–Ni-based alloy system are explored under high-pressure die casting conditions. The addition of La to Al–Ce–Ni-based alloy system only reacts with Ce synergistically to promote the formation of the Al11(Ce,La)3 intermetallic phase as predicted by CALculation of PHAse Diagrams (CALPHAD) and verified experimentally. High Fe additions react with Ni to form the Al9FeNi intermetallic phase, which is an additional eutectic former. The targeted co-precipitation type eutectic morphology is achieved in the alloys studied. Additional coarse particles of Al11(Ce,La)3, present in the alloys studied and not predicted by CALPHAD, are attributed to possible inclusions of Ce and La oxide, present in the mischmetal feedstock used. Both alloys exhibit exceptional mechanical stability after 10 hours at 400 °C due to the stability of the phases formed during solidification. The alloy with high Fe additions possessed better mechanical properties after heat treatment based on the higher eutectic content and more substantial improvement to the morphology of secondary phases after treatment. [ABSTRACT FROM AUTHOR]

Thermodynamic data is of great significance to investigate the formation and control mechanisms of solidification defects during the casting process of H13 steel which is high in Si, Cr, Mo, and V elements. It has been proven that the conventional Ueshima model based on the equilibrium phase diagrams of Fe-X (X = C, Si, Mn, P, S, Cr, Mo, and V) binary alloys cannot accurately predict the phase transition in the solidification of H13 steel with multi components. So, the pseudo-binary phase diagrams of Fe-X alloys at different initial concentrations were calculated via Thermo-Calc software. And, the datasets of liquidus and δ/γ phase transition temperatures were obtained. Then, a backpropagation (BP) neural network model was developed to predict the δ/γ phase transition temperature. While, the slopes of liquidus lines were fitted. These updates were implanted into the Ueshima model. And, the BP-Ueshima model was validated with the phase transition temperatures measured via the differential scanning calorimetry (DSC) test. Subsequently, the phase transition and solute micro-segregation behaviors in the solidification of H13 steel were analyzed as well as the influences of solute elements. The results show that the predicted liquidus temperature (TL) and solidus temperature (TS) of H13 steel via BP-Ueshima model agree with the experimental results. As the cooling rate increases from 10 to 20 °C/min, the phase transition temperatures change slightly. Both the solidus and liquidus temperatures decrease with increase of the initial contents of solute elements. Increasing the initial contents of C and Mn can enhance TP and Tδ (the vanishing temperature of δ phase), whereas the trend is reversed for the other solute elements. Changes of the phase transition temperatures depends on the segregation behaviors of solute elements. The micro-segregation ratios of solute elements in the liquid phase at the end of solidification decreases in the order of S, P, Si, Mo, C, V, Mn, and Cr, respectively. It is determined by the redistributive capacity at the solid/liquid interface and the back diffusion in the solid phase of solute elements. [ABSTRACT FROM AUTHOR]

To enhance the performance of H13 steel, the effects of the cooling rate on the inclusions, primary carbides, and microstructure in rare-earth H13 steel were investigated. Various remelting experiments on rare-earth H13 steel were conducted. The evolution of inclusions was demonstrated to be Ce–O–S, Ce–O, and Ce–O–As → Ce–O–S → Ce–Al–O, and Al2O3, which could be attributed to the increase in Al elements, decomposition, and flotation of inclusions. The type of primary carbides remained unchanged, but their number increased considerably and their size decreased as the cooling rate increased. The secondary dendrite arm spacing was reduced with a faster cooling rate and was shown to be 7.35 ±2.04 μm; the size of austenite was also reduced. The relationship between secondary dendrite arm spacing and cooling rate was λ= 238.62 × Rc–0.438. The segregation ratio of the alloying elements was estimated based on the Clyne–Kurz model, which indicated that Mo had the highest segregation ratio, followed by V, C, and Cr. The cooling rate increased the segregation ratios of Mo, V, and Cr but had a minimal effect on that of C. The equilibrium phase diagram of rare-earth H13 steel was obtained based on Thermo-Calc software, which was consistent with the experimental results. The study provides theoretical insights for controlling the inclusions, primary carbides, and microstructure in steel. [ABSTRACT FROM AUTHOR]

The phase diagram information of the Nd2O3-SiO2-FeO-Fe2O3 system is basic for the design and development of slag for recycling NdFeB magnets by pyrometallurgical processes. The equilibria phase relations of the Nd2O3-SiO2-FeO-Fe2O3 system were investigated at 1773 K in air using a high-temperature isothermal equilibration technique followed by quenching. Seven two-phase equilibria regions and seven three-phase equilibria regions were observed by X-ray diffraction (XRD) and scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS) analysis of quenched samples. Ternary compounds Nd9.33Si6−xFexO26-δ and Nd0.67Si0.13Fe0.2Oδ were found. The 1773 K isothermal section was constructed for the Nd2O3-SiO2-FeO-Fe2O3 system. [ABSTRACT FROM AUTHOR]

Existing thermodynamic descriptions of the whole Cr–Fe–P system are insufficiently accurate for understanding the thermodynamic behavior of the Cr–Fe–P materials during the manufacturing process. To construct a more precise and consistent thermodynamic database of the Cr–Fe–P system, thermodynamic modeling of the Cr–P and Cr–Fe–P systems was conducted using the CALculation of PHAse Diagrams (CALPHAD) approach based on critical evaluation of the experimental data. The modified quasichemical model and compound energy formalism were employed to describe the liquid and solid solutions, respectively. The Gibbs energies of stoichiometric compounds Cr3P(s), Cr2P(s), CrP(s), and CrP2(s) were carefully determined based on reliable experimental data. The ternary (Cr,Fe)3P, (Cr,Fe)2P, and (Cr,Fe)P phosphides were modeled as solid solutions considering mutual substitution between Cr and Fe atoms. In addition, the phase equilibria of BCC_A2 and FCC_A1 solutions and the liquid phase of the ternary Cr–Fe–P system were also optimized for more accurate descriptions of existing phase equilibria and thermodynamic properties data. As an application of the present database, the experimentally unexplored thermodynamic properties and phase diagrams of the Cr–Fe–P system are predicted. [ABSTRACT FROM AUTHOR]

This work aims to determine how the nematic twist-bend phase (NTB) of bismesogens containing two rigid parts of cyanobiphenyls connected with a linking chain containing n = 7, 9, and 11 methylene groups behaves in mixtures with structurally similar cyanobiphenyls nCB, n = 4–12, 14. The whole phase diagrams are presented for the CB7CB-nCB system. For the other systems, CB9CB-nCB and CB11CB-nCB, only curves corresponding to NTB-N phase transition are presented. Based on the temperature-concentration range of the existence of NTB phase, it was established that an increase in the alkyl chain length of CBnCB causes an increase in the stability of the NTB phase. But surprisingly, an increase in the alkyl chain length of nCB compounds does not change the slope of the NTB-N equilibrium line on phase diagrams. It is slightly bigger when the nCB compound has the same length of alkyl chain as the length of the linking group of a bismesogen. XRD studies were carried out for two mixtures. [ABSTRACT FROM AUTHOR]

The Na2O‐SiO2‐TiO2 system is important for the glass, ceramic, and metallurgical industries. Its features provide information on the composition and melting temperature to be utilized during the production of glass and ceramic and during the processing of TiO2‐bearing material in the metallurgical industry. The liquidus temperatures between 900 and 1600°C in the ternary system at saturation of solid SiO2, TiO2, Na2Ti6O13, Na2SiTiO5, and Na2Ti3O7 were measured using the equilibration‐quenching energy‐dispersive X‐ray spectroscopy/Electron Probe Microanalyzer technique. A wide range of liquidus compositions were obtained with Na2O between 0 and 41.7 mol% in the SiO2‐ and TiO2‐rich regions. The present study provides liquidus data at 1500 and 1600°C for the first time. Liquidus temperatures at various double saturations were also obtained in the present investigation to determine univariant lines in the phase diagram. The present experimental data were compared with previous investigations and computed phase diagrams. The data obtained in the present investigation can be employed to optimize the thermodynamic properties and phase diagrams of the Na2O‐SiO2‐TiO2 system. [ABSTRACT FROM AUTHOR]

The 1773 K phase diagram of the TiO 2 –SiO 2 –CaO-10 wt%Al 2 O 3 -7.5 wt%MgO system was constructed experimentally using the quenching method, focusing on the composition range of high TiO 2 content. The obtained isothermal section contains four phase fields: the liquid phase field, the primary phase field of pseudo-brookite, the primary phase field of perovskite, and the liquid + perovskite + pseudo-brookite phase field. The pseudo-brookite particle precipitated in its primary phase field is more suitable for the efficient selective enrichment and separation of titanium resources. The increase of MgO from 5 % to 7.5 % in the TiO 2 –CaO–SiO 2 -10 wt%Al 2 O 3 –MgO system leads to a decrease of the liquidus temperature and an expansion of the liquid + pseudo-brookite + perovskite phase field. The increase of MgO promotes the enrichment of TiO 2 into the pseudo-brookite phase and reduces the TiO 2 level in the glass phase. [ABSTRACT FROM AUTHOR]

The phase equilibria of the Cu–Ti–V system were investigated via key experiments coupled with thermodynamic modeling. The isothermal sections at 600 °C, 700 °C, and 800 °C were constructed using X-ray diffraction (XRD) and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDS). The solubilities of Cu in the (βTi, V) phase and V in intermediate phases Cu4Ti, Cu3Ti2, Cu4Ti3, CuTi, CuTi2, and CuTi3 were determined. Based on the thermodynamic descriptions of three binary subsystems and the experimental data, the thermodynamic assessment of the Cu–Ti–V system was carried out by means of the CALPHAD (CALculation of PHAse Diagrams) method. A set of thermodynamic parameters for the Cu–Ti–V system was obtained and the calculated phase equilibria were consistent with the experimental results. The liquidus projection and the reaction scheme of the Cu–Ti–V system were constructed. This work provides important phase equilibria and thermodynamic data for the composition and process design of new copper alloys. [ABSTRACT FROM AUTHOR]

Copyright of Precious Metals / Guijinshu is the property of Precious Metals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Phase separation in aqueous solutions of macromolecules underlies the generation of biomolecular condensates in cells. Condensates are membraneless bodies, representing dense, macromolecule-rich phases that coexist with the dilute, macromolecule-deficient phases. In cells, condensates comprise hundreds of different macromolecular and small molecule solutes. How do different solutes contribute to the driving forces for phase separation? To answer this question, we introduce a formalism we term energy dominance analysis. This approach rests on analysis of shapes of the dilute phase boundaries, slopes of tie lines, and changes to dilute phase concentrations in response to perturbations of concentrations of different solutes. The framework is based solely on conditions for phase equilibria in systems with arbitrary numbers of macromolecules and solution components. Its practical application relies on being able to measure dilute phase concentrations of the components of interest. The dominance framework is both theoretically facile and experimentally applicable. We present the formalism that underlies dominance analysis and establish its accuracy and flexibility by deploying it to analyze phase diagrams probed in simulations and in experiments. [ABSTRACT FROM AUTHOR]

The recovery of rare-earth elements (REEs) from rare-earth blast furnace slag (RE-BFS) is crucial for advancing the circular economy. However, the development of related processes is significantly hindered by the severe lack of fundamental thermodynamic data on REE systems, underscoring the urgent need for detailed studies in this area. In the present work, the equilibrium phase relations of CaO-SiO2-CeO2-10.0 wt.% Al2O3-5.0 wt.% MgO system at 1300°C and 1400°C were experimentally carried out using the high-temperature equilibration-quenching technique followed by X-ray diffraction (XRD), scanning electron microscopy–energy dispersive X-ray spectroscopy (SEM-EDS), and X-ray photoelectron spectroscopy (XPS), as well as thermodynamic calculation. One liquidus region, a liquid–CeO2 two-phase coexisting region, and a liquid–CeO2–akermanite three-phase coexisting region were confirmed within the investigated composition ranges. Based on the experimental data and phase compositions, the phase diagram of the CaO-SiO2-CeO2-10.0 wt.% Al2O3-5.0 wt.% MgO system was constructed at 1300°C and 1400°C. There were great discrepancies between the experimental results and calculated results by FactSage 8.2. The phase equilibria data obtained from this study provide fundamental thermodynamic information for the development of innovative processes aimed at extracting REEs from RE-BFS, as well as enriching the existing REEs database. [ABSTRACT FROM AUTHOR]

To fully understand the metallogenic regularity and the geochemical equilibrium rules of brine migration and transformation among potassium, barium and strontium in gas field water, the isothermal dissolution equilibrium method was used to study the phase equilibria of quaternary system KCl + BaCl2 + SrCl2 + H2O and its two ternary systems BaCl2 + SrCl2 + H2O and KCl + BaCl2 + H2O at 323 K. The equilibrium liquid phase compositions of each system was measured, the corresponding equilibrium solid phases were identified by chemical analysis and X-ray powder diffraction, and the equilibrium phase diagrams were drawn. No double salts or solid solutions were found in the ternary systems BaCl2 + SrCl2 + H2O and KCl + BaCl2 + H2O at 323 K and the phase diagrams both contain one invariant point, two isothermal solubility curves and two crystallization regions. The hydrate forms in the quaternary system KCl + BaCl2 + SrCl2 + H2O at 323 K are the same as those of its subsystems. The quaternary phase diagram contains one invariant point, three isothermal solubility curves and three crystallization regions, where the equilibrium solid phases are KCl, BaCl2·2H2O and SCl2·6H2O. These results provide basic thermodynamic data for the design of a comprehensive utilization process of potassium, barium and strontium resources in gas field water. [ABSTRACT FROM AUTHOR]

Through experimental study of carefully crystallized via long-term thermal annealing alloys using powder X-ray diffraction and differential thermal analysis methods, as well as considering the evidence from the literature, a comprehensive picture of phase equilibria in the Cu2Se-Cu3AsSe4-As2Se3 system was obtained. The projection of the liquidus surface, the isothermal section at 500 K, and three vertical sections of the phase diagram are presented and discussed. The fields of primary crystallization of phases, types, and coordinates of invariant and monovariant phase equilibria are determined. The side Cu2Se-As2Se3 system was re-investigated and its refined phase diagram was constructed. It is shown that this system is quasi-binary and is characterized by the formation of ternary Cu3AsSe3 and CuAsSe2 compounds. [ABSTRACT FROM AUTHOR]

Phase equilibria were investigated between 200 and 800 °C in the Cu-Zn binary system. Wavelength dispersive spectroscopy (WDS) was performed to determine the equilibrium compositions, and differential scanning calorimetry (DSC) was performed to investigate the solidus and liquidus temperatures and the invariant reaction temperatures of the Zn-rich portion. The β/(α + β) boundary in the Cu-rich portion extended toward the Cu-rich side as the temperature decreased below the A2–B2 order–disorder transformation temperature, and the phase boundaries of the γ, δ and ε phases shifted toward the Cu-rich side. The liquidus temperatures of the ε + liquid were higher than those of the previous report. From the experimental results, the phase diagram of the Cu-Zn binary system was determined in the whole composition range. [ABSTRACT FROM AUTHOR]

The Mg-Sm phase diagram has been experimentally studied by x-ray diffraction, scanning electron microscope equipped with energy dispersive spectrometer, and differential scanning calorimetry. Five binary compounds, Mg41Sm5, Mg5Sm, Mg3Sm, Mg2Sm and MgSm were confirmed to exist in the Mg-Sm system. In addition to Mg2Sm and MgSm, Mg3Sm was found to be a congruently melting phase. The Mg5Sm and Mg2Sm were found to be only stable at high temperatures and decompose above 400 °C in this work. A special effort was made to determine the extent of the solid solubility ranges of Mg3Sm, Mg2Sm, MgSm and, γ-Sm. The Mg-Sm binary system was modeled using the Calphad approach based on new experimental data of this work and all reliable experimental information from literature. A complete thermodynamic description of the Mg-Sm system is obtained and extensive comparisons between calculated and experimental data are presented, indicating that almost all available experimental and theoretical data are fitted satisfactorily. [ABSTRACT FROM AUTHOR]

The phase diagram of the Fe-Zn binary system was evaluated based on the CALPHAD method with reference to the latest experimental data. The solubility ranges of the intermetallic compound phases, Γ-Fe4Zn9, Γ1-Fe11Zn40, δ1k-FeZn7, δ1p- Fe13Zn126, and ζ-FeZn13 were modeled considering their structures consisting of Zn12 icosahedra with Fe at the center (Fe1Zn12 clusters) as well as glue-like Fe and Zn atoms, and the miscibility gap between the δ1k and δ1p phases was also taken into account in the present calculations. The solubility of Fe in the liquid and (ηZn) phases that was confirmed as dozens of times larger than the values reported in the earlier literature could be calculated by introducing Fe1Zn12 associates to these solution phases. Consequently, all phase equilibria were adequately reproduced by the thermodynamic models and parameters revised in the present study. [ABSTRACT FROM AUTHOR]

This article considers the features and fundamental difficulties of studying low-temperature phase equilibria associated with an exponential increase in the required duration of syntheses with a decrease in temperature. Methods for accelerating the achievement of equilibrium, including the use of salt solvents, are also considered. The results of phase equilibria studies in the SrF2–LaF3 system using sodium nitrate and in the ZrO2–Sc2O3 system using sodium sulfate as fluxes are presented. The methods of extrapolation of phase diagrams to absolute zero temperature in accordance with the third law of thermodynamics are considered. Phase diagrams of the Au–Cu, Cu–Pd, Ni–Pt, and ZrO2–Y2O3 systems are presented. Phase equilibria with plagioclase ordering are considered separately, and the phase diagram of the albite–anorthite (NaAlSi3O8–CaAl2Si2O8) system is presented. As the temperature approaches absolute zero, the homogeneity region of labradorite shrinks to the compound NaCaAl3Si5O16. [ABSTRACT FROM AUTHOR]

In this paper, the NaBr-RbBr binary system was computationally investigated. Experimental data including phase diagram and thermodynamic information are used as input data for the CALPHAD assessment. The liquid and solid solutions are treated as substitutional solutions and the solid solutions (NaBr, RbBr, both FCC type) were modeled as a single phase with a miscibility gap. Our calculations are in good agreement with the phase diagram data and experimental thermodynamic data available in the literature. [ABSTRACT FROM AUTHOR]

Phase equilibria in the Pd rich region of the Au-Cu-In-Pd quaternary at 500 °C and 800 °C are investigated by SEM, EDX and XRD techniques. Part of the isothermal tetrahedron was constructed accounting for published data for bounding ternaries obtained earlier by the present authors. No quaternary phases were detected. The solubility of copper in the τ1 phase of the Au-In-Pd ternary (AuCu3 structural type) does not exceed 5 at.%. Gold solubility in the InPd2Cu phase of the Cu-In-Pd ternary is not less than 18 at.% at 500 °C, and at least 15 at.% at 800 °C. Analytical description of the boundaries of the FCC solid solutions in the equilibrium with the InPd3, InPd2Cu and ternary τ1 phase was performed for bounding Cu-In-Pd and Au-In-Pd ternaries as well as for the quaternary. The tie-lines of the equilibria, i.e. the compositions of the two phases in equilibrium, were described as a single entity. To this end, the approach used in the literature for regression analysis of phase compositions of the (γ + γ′) Ni based superalloys was modified. The parametric descriptions of the two-phase tie-lines' centers and those of the distribution coefficients of the components between the phases were built. The choice of parametrization is discussed. In particular cases of the ternaries and quaternary studied using the content of one or two of the components as parameters proved to be quite satisfactory. Very good description of the solubility lines and solubility surface including rather fine details has been achieved.Please check and confirm the edit made in the article title.Ok [ABSTRACT FROM AUTHOR]

The paper analyzes the works of the last decade on the study of ionic conductivity, thermoelectric, photovoltaic, photocatalytic, optical, etc. properties of the argyrodite family compounds (prototype Ag8GeS6), as well as phases and composite materials based on them. Considered works allow us to characterize them as valuable environmentally friendly functional materials with great potential for practical application. The main approaches which have been used in these works to enhance functional properties, as well as to improve the application capabilities of this class of substances have been analyzed. The importance of further systematic investigations on their design based on the "composition-structure-property" relationship has been noted. In the present review, special attention is paid to the analysis of works on phase equilibria in the corresponding systems since the information accumulated in phase diagrams is extremely important for optimizing the properties of compounds through targeted variation of composition and structure. Available data on the phase equilibria and thermodynamic properties of ternary and quaternary systems forming Cu/Ag argyrodite compounds and solid solutions based on them are presented and analyzed. It has been shown that anionic and Cu ↔ Ag substitutions in compounds lead to a strong decrease in their polymorphic phase transition temperatures and an expansion of the temperature-composition ranges of the existence of high-temperature ion-conducting phases up to room temperature and below. The possibility of replacing part of the chalcogen atoms in the compounds with halogens, and the Cu(Ag) atoms with elements of the zinc subgroup, which expands the range of argyrodite phases is also shown. The significance of expanding studies of phase equilibria and thermodynamic properties of these systems, especially five-component and more complex systems possessing a big possibility of the formation of high-entropy argyrodite phases, which have thermodynamic stability in a wide temperature-composition range and better applied characteristics has also been specified. [ABSTRACT FROM AUTHOR]

The conditions of pyrite (Py) stability inform the extent of S mobility during prograde metamorphism, the formation of orogenic Au deposits, and the S cycle in subduction zones. The variables that affect Py stability and chalcophile element mobility are investigated in the Pacific Rim Terrane of Vancouver Island, Canada, where sulfide-bearing carbonaceous sediments have been metamorphosed from 230 to 600 °C and 4 kbar by mid-ocean ridge subduction in a hot fore arc setting during the Eocene. The petrographic evidence in the rocks shows Py can coexist with pyrrhotite (Po) over a wide temperature window to >550 °C as preserved in porphyroblasts of andalusite, staurolite, and garnet. Conversely, equilibrium phase diagrams constructed for the rock compositions conflict with observations and suggest the breakdown of primary Py occurs over a narrow temperature range below 400 °C. The phase diagrams are consistent with the coexistence of Py and Po up to lower amphibolite facies only if S locally comprises a much greater proportion involved in a reaction than that of the overall bulk-rock composition used in the calculations. While the chemistry of the bulk rocks and Po included in porphyroblasts show mobilization of H2O and S with increasing metamorphic grade of the forearc, this process appears unrelated to the distribution of chalcophile elements or Au deposits found in the Pacific Rim Terrane. [ABSTRACT FROM AUTHOR]

When the calculation of phase diagram (CALPHAD) method is applied to the Au-Ag-Al ternary phase diagram, the accuracy of three marginal binary phase diagrams (Au-Al, Au-Ag, Ag-Al) has a great impact on the calculating results. At present, there are some contraditions in the Au-Al marginal binary phase diagram. Therefore, based on a comprehensive evaluation of experimental data for the Au-Al system, the equilibrium phase diagrams were optimised and calculated by using a solid solution model to describe the Gibbs free energy of the liquid, Bcc and Fee phases in the Au-Al system, and by using the sublattice models (Al)(Au)4, (Al)3(Au)8, (Al)(Au)2, (Al)(Au) and (A1,AU)2(A1,AU) to describe the A1AU4, Al3Au8, A1AU2, AlAu and AL2Au phases. A set of reasonably self-consistent thermodynamic parameters was obtained via optimizing with Pandat software. Au-Al phase diagrams calculated in this way agreed well with the experimental and thermodynamic data. Combined with thermodynamic parameters of Au-Ag and Ag-Al, the Au-Ag-Al liquid-phase, surface projections and isothermal cross-sections were calculated. The liquid- phase surface projections revealed the existence of eight four-phase equilibrium reactions in this ternary system, and these results may be helpful in studying the Au-Ag-Al alloys. [ABSTRACT FROM AUTHOR]

Knowledge about the thermodynamic equilibria of the P2O5-Na2O and P2O5-MgO systems is very important for controlling the phosphorus content of steel materials in the process of steelmaking dephosphorization. The phase equilibrium and thermodynamic data of the P2O5-Na2O and P2O5-MgO systems were critically evaluated and re-assessed by the CALPHAD (CAlculation of PHAse Diagram) approach. The liquid phase was described by the ionic two-sublattice model for the first time with the formulas (Na+1)P(O−2, PO3−1, PO4−3, PO5/2)Q and (Mg+2)P(O−2, PO3−1, PO4−3, PO5/2)Q, respectively, and the selection of the species constituting the liquid phase was based on the structure of the phosphate melts. A new and improved self-consistent set of thermodynamic parameters for the P2O5-Na2O and P2O5-MgO systems was finally obtained, and the calculated phase diagram and thermodynamic properties exhibited excellent agreement with the experimental data. The difference in the phase composition of invariant reactions from the experimentally determined values reported in the literature is less than 0.9 mol.%. The present thermodynamic modeling contributes to constructing a multicomponent oxide thermodynamic database in the process of steelmaking dephosphorization. [ABSTRACT FROM AUTHOR]

Aqueous two-phase extraction (APTE) stands out as an environmentally friendly technique for the separation of metal ions. The separation of Re (VII) and Mo (VI) in an aqueous solution was investigated using a novel aqueous two-phase system (ATPS) consisting of isodecanol polyoxyethylene ether (E-1006), ammonium sulfate, and water. A phase diagram of this system was developed, and the effects of pH, temperature, extraction time, the concentrations of E-1006 and (NH4)2SO4, and metal ions on the separation of Re (VII) and Mo (VI) were examined. The results show that at pH 7.0, Mo (VI) had almost transformed into the (NH4)2SO4-rich phase, while Re (VI) was extracted into the E-1006-rich phase. The increase in temperature induces a transition of Mo (VI) to the salt-rich phase, which is unfavorable for the extraction of Re (VII). The increase in the concentrations of E-1006 and (NH4)2SO4 has a positive effect on the separation of rhenium and molybdenum. Overall, the ATPS consisting of 200 g/L of E-1006, 200 g/L of (NH4)2SO4, and water yields an extraction efficiency of 97.2% for Re and a high separation factor of 2700 for Re (VII) and Mo (VI) from a mixture of 0.1 g/L of Re (VII) and 5 g/L of Mo (VI) at pH 7.0 and 323.15 K. Separation studies of the simulated leaching solution show that the extraction efficiency for Re (VI) is 99.1% and the separation factor of Re (VII) and Mo (VI) is 5100. [ABSTRACT FROM AUTHOR]

Modulating the interaction potential between colloids suspended in a fluid can trigger equilibrium phase transitions as well as the formation of non-equilibrium "arrested states," such as gels and glasses. Faithful representation of such interactions is essential for using simulation to interrogate the microscopic details of non-equilibrium behavior and for extrapolating observations to new regions of phase space that are difficult to explore in experiments. Although the extended law of corresponding states predicts equilibrium phases for systems with short-ranged interactions, it proves inadequate for equilibrium predictions of systems with longer-ranged interactions and for predicting non-equilibrium phenomena in systems with either short- or long-ranged interactions. These shortcomings highlight the need for new approaches to represent and disambiguate interaction potentials that replicate both equilibrium and non-equilibrium phase behavior. In this work, we use experiments and simulations to study a system with long-ranged thermoresponsive colloidal interactions and explore whether a resolution to this challenge can be found in regions of the phase diagram where temporal effects influence material state. We demonstrate that the conditions for non-equilibrium arrest by colloidal gelation are sensitive to both the shape of the interaction potential and the thermal quench rate. We exploit this sensitivity to propose a kinetics-based algorithm to extract distinct arrest conditions for candidate potentials that accurately selects between potentials that differ in shape but share the same predicted equilibrium structure. The algorithm selects the candidate that best matches the non-equilibrium behavior between simulation and experiments. Because non-equilibrium behavior in simulation is encoded entirely by the interparticle potential, the results are agnostic to the particular mechanism(s) by which arrest occurs, and so we expect our method to apply to a range of arrested states, including gels and glasses. Beyond its utility in constructing models, the method reveals that each potential has a quantitatively distinct arrest line, providing insight into how the shape of longer-ranged potentials influences the conditions for colloidal gelation. [ABSTRACT FROM AUTHOR]

Solid-solid phase transitions are investigated in Zr thin films using shock compression induced by a short laser pulse (<1 ns). Shock wave profiles are measured at free surfaces for films of different thicknesses (a few micrometers) using chirped-pulse line velocimetry with 10 ps time resolution. Experiments are performed at pressures up to ∼50 GPa, which is sufficient to reach the ω and β phases under equilibrium conditions. The shock wave structures are analyzed using a general Lagrangian analysis method, which allows for the calculation of stress–strain paths and assessments of phase transition behavior. In agreement with recent short laser pulse experiments using ultra-fast x-ray diffraction, we do not find any clear evidence of the α–ω transition, though this would be expected from the phase diagram. Instead, we infer a direct transformation to a metastable β-phase at lower shock pressures (<20 GPa) and equilibrium β at higher pressures. Through the velocimetry analysis, we find α–β transformation onset times of less than ∼100 ps and completion times of less than ∼200 ps. [ABSTRACT FROM AUTHOR]

NaCl aqueous solutions are ubiquitous. They can crystallize into ice, NaCl, or NaCl · 2H2O depending on the temperature–concentration conditions. These crystallization transitions have important implications in geology, cryopreservation, or atmospheric science. Computer simulations can help understand the crystallization of these solids, which requires a detailed knowledge of the equilibrium phase diagram. We use molecular simulations in which we put at contact the solution with the solid of interest to determine points of the solid–solution coexistence lines. We follow two different approaches, one in which we narrow down the melting temperature for a given concentration and the other in which we equilibrate the concentration for a given temperature, obtaining consistent results. The phase diagram thus calculated for the selected model (TIP4P/2005 for water molecules and Joung–Cheatham for the ions) correctly predicts coexistence between the solution and ice. We were only able to determine NaCl · 2H2O–solution coexistence points at higher temperatures and concentrations than in the experiment, so we could not establish a direct comparison in this case. On the other hand, the model underestimates the concentration of the solution in equilibrium with the NaCl solid. Our results, alongside other literature evidence, seem to indicate that ion–ion interactions are too strong in the model. Our work is a good starting point for the improvement of the potential model and for the study of the nucleation kinetics of the solid phases involved in the phase diagram. [ABSTRACT FROM AUTHOR]

Phase equilibria of the Ti-Ga-Sn system have been determined at primary crystallization and at 1000 °C in the composition interval ~ 50-100 at.% Ti based on differential thermal analysis, x-ray powder diffraction, scanning electron microscopy and electron microprobe analysis. Partial liquidus and solidus projections, the melting diagram, a number of vertical sections, isothermal section at 1000 °C, as well as the reaction scheme (Scheil diagram) for the Ti-Ga-Sn system were constructed. A ternary compound Ti5GaSn2 (τ) (Nb5SiSn2-type structure, tI32-I4/mcm), found by us previously, forms by peritectic reaction L + Ti2(Sn, Ga) + Ti5(Sn, Ga)3-4 ⇄ τ at 1500 °C and has a wide homogeneity range from 9 to 23.5 at.% Ga at solidus temperature and from 4 to 34 at.% Ga at 1000 °C, and located along constant composition of ~ 62.5 at.% Ti. D88-type compounds Ti5Sn3 and Ti5Ga4 form a continuous solid solution, denoted Ti5(Sn, Ga)3-4, at all investigated temperatures. Ga-poor part of it (below ~ 12.5 at.% Ga) forms by an interstitial mechanism, while in the interval above ~ 12.5 at.% Ga it is a substitutional phase. Isostructural compounds Ti2Sn and Ti2Ga also form a continuous solid solution Ti2(Sn, Ga) at solidus temperatures, which decomposes with decreasing temperature. Meanwhile, at 1000 °C, one more continuous solid solution Ti3(Sn, Ga) forms between isostructural compounds Ti3Sn and Ti3Ga. [ABSTRACT FROM AUTHOR]

The liquid phase projection diagram, three-dimensional phase diagram, and vertical section diagram of the Zn–x%Al–x%Mg alloy system was calculated using the phase diagram calculation software Pandat. Simultaneously making full use of the self-developed hot-dip galvanizing process simulation machine by China Steel Research produced a 75%Zn–19%Al–6%Mg coating. A method combining phase diagram calculations and experimental verification was used to investigate the equilibrium phases and solidification process of the alloy. The microstructure of the 75%Zn–19%Al–6%Mg coating was studied using scanning electron microscopy and energy dispersive spectrometry. The results indicate that the coating structure consists of primary Al dendrite phase, MgZn2 inter-metallic compound and Zn-rich phase. There is no ternary eutectic structure in the coating structure. Al dendrites grow on the surface of the coating, while there are no Al dendrites on the cross-section. The experimental results strongly concur with the calculated results from the Pandat phase diagram. The solidification sequence of the 75%Zn–19%Al–6%Mg coating is L→L + Al→L + Al + MgZn2→Al + MgZn2 + Zn. The phase diagram guides industrial production significantly, avoiding the waste of transitional materials and zinc caused by small scale trial and error experiments, thus reducing unnecessary production costs. The factory can select a reasonable coating composition designing scheme in the phase diagram, based on the performance requirements of customers for the coating. [ABSTRACT FROM AUTHOR]

The article discusses the features of the chemical composition and the formation of intergrowths of platinum-group minerals, gold, gold-bearing phases, and other ore minerals present in placers collected from the Anabar River in the northeast part of the Siberian platform. Based on an analysis of changes in the phase compositions of these intergrowths of noble metals with other ore minerals on (Pt, Pd)-Fe-Au and Pd-Cu-Au phase equilibrium diagrams, potential trends in the crystallization of natural polymineral alloys from multicomponent low-sulfide metallic liquids are discussed. The similarity of the microstructures of natural and metallurgical alloys indicates that the formation of natural multiphase Au-PGE intergrowths occurred in a similar manner to the crystallization of multicomponent synthetic alloys. The authors suggest that magmatic Au-PGE mineralization occurs during the crystallization of a noble-metal-containing, low-sulfide, Cr-rich oxide melt separated from silicate mafic–ultramafic magma. Magmatic gold–platinum deposits are commonly associated with sulfide or oxide disseminated-schlieren ores in layered mafic–ultramafic intrusions. However, due to the high solubility of gold and platinoids in sulfide minerals, PGMs in sulfide ores occur as isomorphic impurities or as microphases and dispersed inclusions that cannot form placers. Therefore, the authors suggest that magmatic Au-PGE mineralization occurs during the crystallization of an immiscible low-sulfide, high-Cr oxide liquid separated from silicate mafic–ultramafic magma. In the northeast part of the Siberian platform, potential sources for these placers are likely alkaline, high-Ti mafic–ultramafic intrusions, as confirmed by the presence of silicate inclusions in ferroan platinum similar in composition to melteigite. [ABSTRACT FROM AUTHOR]