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Here, we aim to comprehend the mechanism of the order–order transition (OOT) from nonequilibrium, metastable phase to equilibrium phase. Polystyrene-block-polydimethylsiloxane (PS-PDMS) block copol...

The mechanism governing the deoxidation of vanadium metal is regarded as fundamental knowledge; however, it has not been elucidated in existing literature. In this paper, the thermodynamic data of V-H-O systems were summarized, and the Gibbs free energies of the main compounds were calculated. Consequently, the deoxidation limits of different reductants in a V-O system were evaluated, namely: Si, Al, and Mg. It was observed that Si cannot remove an O content of less than 7.27 wt% from V. However, Al was the stronger reducing agent; it could remove O contents of up to 0.01 and 0.1 wt% at 800 and 1050 ?C, respectively. Nevertheless, Mg exhibited the best reducing properties as it could remove less than 0.01 wt% of O at 1100 ?C. The addition of H2 renders the V-O solid solution unstable to a certain extent, thereby indicating that H2 facilitates deoxygenation. Furthermore, the results obtained by analyzing the equilibrium conditions were in accordance with the results of the deoxidation limit in the V-O system. In other words, this study demonstrates that the oxygen in vanadium can be effectively controlled by changing the reductant dosage and temperature.

In order to optimize the composition and microstructure of quasicrystalline strengthened Mg-based alloy, the equilibrium phases of Mg-Zn-Y-Zr alloys with three components were studied by using thermodynamic calculation. The calculated results showed that the equilibrium phases of the three alloys were mainly Liquid phase, α-Mg matrix phase, α-Zr dispersed phase, quasicrystalline strengthening I phase, W phase and Z phase. It was observed that the specific content and temperature range of these phases were different. Among them, alloy 3 had the highest quasicrystalline content. And alloys 1 and 2 contained dispersed phase α-Zr which can lead to grain refinement.

The thermodynamic properties of ruthenium complex compound Ru(thd)3, (thd is tris(2,2,6,6-tetramethyl-3,5-heptadionate), Ru(C11H19O2)3 have been studied. Temperatures (434.8 ± 2.0, 452.2 ± 1.0, and 461.1 ± 1.0, and 487.8 ± 1 K) and thermodynamic parameters (enthalpy change ΔH = 13.3 ± 2.0, 2.1 ± 0.5, 6.0 ± 2.0, and 3.8 ± 1 kJ mol–1) of three reversible solid-phase transitions and the melting process have been determined by differential scanning calorimetry. The temperature dependence of the saturated vapor pressure in the range 392–488 K has been established by the flow method. The thermodynamic parameters of sublimation (enthalpy change ΔH = 121 ± 1, 103 ± 3, 101 ± 5, and 86 ± 2 kJ mol–1; entropy change ΔS° = 219 ± 3, 176 ± 7, 173 ± 10, 141 ± 4 J mol–1 K–1) for all four crystalline phases have been calculated. CVD diagrams have been calculated by thermodynamic modeling to determine the equilibrium phase composition of the system. The obtained results allow us to give recommendations on finding the optimal conditions for the CVD process and choosing the precursor.

Finding safe solvents with low viscosities has been in great demand in extraction processes. Herein, R-(−)-carvone, a natural monoterpenoid rich in spearmint, was mixed with naturally occurring fatty acids and terpenes. Most eutectic mixtures presented a wide liquid window in the solid-liquid equilibrium phase diagrams. Carvone mixtures at the ideal eutectic points were characterized for physicochemical properties. Despite varying properties, all the tested solvents were immiscible with water and displayed low viscosity with reasonable biodegradability. Sigma potentials of the mixtures were applied to machine learning algorithms, suggesting carvone mixtures as substitutes for polar protic and dipolar aprotic solvents. Carvone mixtures could be successfully applied to liquid-liquid extraction of a red algae called laver, which is rich in natural hydrophobic and hydrophilic pigments of high value. This study proposes carvone as a new bio-based source of hydrophobic solvents and the eutectic mixtures as biodegradable and tunable solvents to extract hydrophobic compounds.

The equilibrium phase behavior of main-chain liquid-crystalline polymer brushes in good solvent is investigated using self-consistent field theory. The calculation assumes semidilute brushes, where the grafting density is sufficient to cause overlap among the polymers but low enough to allow the solvent to be treated implicitly. The polymers are modeled as semiflexible wormlike chains with Maier–Saupe interactions. Previous calculations based on freely jointed chains have predicted that extended brushes collapse into folded nematic brushes, as the liquid-crystalline interaction strength is increased. For the more sophisticated model of wormlike chains, which penalizes hairpin folds, we find that extended brushes become unstable with respect to tilting prior to the onset of folding. This implies that the brushes spontaneously collapse by a symmetry-breaking transition, where the chains tilt rather than fold.

Preferential attraction of polymer chains to the substrate [i.e., poly(methyl methacrylate) (PMMA) on the hydroxyl-terminated Si substrate] typically results in the initial phase separation of spin-cast immiscible linear polymer blends [i.e., polystyrene (PS)/PMMA] with a characteristic interfacial microstructure depending on their molecular weight. A formation of the undesired microstructure in those blends is inevitable because of the thermodynamic force driving their phase separation combined with relatively rapid dynamics in solution. In contrast, the polymer ligands, which are grafted from nanoparticles, are capable of limited segmental interactions in the presence of segmental contacts of chemically distinct chains as well as hindered mobility by interpenetration (or entanglement) and thus exhibit a homogeneous but non-equilibrium phase behavior. Here, the microstructure of the blends consisting of immiscible polymer-grafted nanoparticles (PGNPs) was identified by their neutron reflectivity, in whic...

The solid–liquid equilibrium of the quaternary system (KBr + NaBr + MgBr2 + H2O) was accurately investigated at 298 K. The equilibrium phase diagram was obtained and consisted of seven dissolution isotherms, three co-saturated points and five solid crystallization regions under the condition of 298 K. The five solid crystallization regions contain four single salts NaBr·2H2O, NaBr, KBr, MgBr2·6H2O and one double salt KBr·MgBr2·6H2O, respectively. The largest crystallization region corresponds to KBr comprising more than half of the region of the equilibrium phase diagram. Using Pitzer’s model and mathematical calculation tools, the solubilities of the bromide minerals in this system were calculated; the calculation results are basically consistent with the experimental results. The research in this paper is of great significance in guiding the development of bromine resources of underground brines in the Western Sichuan Basin and providing fundamental thermodynamic data of bromine-containing systems.

There are many papers concerning H in Pd alloys but their corresponding para-equilibrium phase diagrams have not been given. Para-equilibrium is the most common condition under which data are obtained for Pd alloy-H systems and refers to the condition where the mobile interstitial species (H) reaches equlibrium within an immobile metal alloy framework. Based on these para-equilibrium phase diagrams, an explanation will be offered for the experimental observation that the terminal hydrogen solubilities are always greater in fcc, substitutional Pd alloys than in Pd itself where this term refers to the limiting solubility of H in the dilute phase before the hydride phase forms.

We studythe effect of shear deformation on graphitic g-C3N4 under pressures of up to 80 GPa at room temperature. g-C3N4 samples are transformed from initial amorphous flakes into onion-like structures, in which the nitrogen content in the quenched samples decreases with increasing pressure (from 42% in the initial conditions to 1% at 80 GPa). The concentration of the sp2 bonds also decreases from 1 (the initial sample) to 0.62 with increasing pressure to 80 GPa. This transformation of the sample is due to the fact that in the pressure range of 55–115 GPa, the equilibrium phase is not a diamond, but instead, carbon onions cross-linked by sp3 bonds, which are denser than diamonds. The results of our study show that the presence of nitrogen in sp3-bonded structures at pressures of higher than 55 GPa reduces the density and, accordingly, carbon structures without nitrogen become thermodynamically favorable.

Abstract Biomolecular condensates in cells are often rich in catalytically active enzymes. This is particularly true in the case of the large enzymatic complexes known as metabolons, which contain different enzymes that participate in the same catalytic pathway. One possible explanation for this self-organization is the combination of the catalytic activity of the enzymes and a chemotactic response to gradients of their substrate, which leads to a substrate-mediated effective interaction between enzymes. These interactions constitute a purely non-equilibrium effect and show exotic features such as non-reciprocity. Here, we analytically study a model describing the phase separation of a mixture of such catalytically active particles. We show that a Michaelis–Menten-like dependence of the particles’ activities manifests itself as a screening of the interactions, and that a mixture of two differently sized active species can exhibit phase separation with transient oscillations. We also derive a rich stability phase diagram for a mixture of two species with both concentration-dependent activity and size dispersity. This work highlights the variety of possible phase separation behaviours in mixtures of chemically active particles, which provides an alternative pathway to the passive interactions more commonly associated with phase separation in cells. Our results highlight non-equilibrium organizing principles that can be important for biologically relevant liquid-liquid phase separation. Graphic abstract

The effect of solvent species and quantity of solvent used for spreading on the morphology of Langmuir monolayer composed of palmitic and lignoceric acids was investigated based on atomic force microscopy observations. The variation in domain size depending on the evaporation time of the spreading solution indicated that the mixed monolayer was in a non-equilibrium phase-separated state.

Despite the long history behind the experimental determinations of gas solubility and the consequent wealth of experimental data for binary systems we are still confronted with lingering issues regarding their reliability, the approximations behind their modeling, and the consistency among resulting solvation quantities. In the present effort we discuss cautiously these issues through the thermodynamic scrutiny of the coexistence phase equilibrium equations involving sparingly soluble species according to the recently proposed rigorous molecular-based solvation formalism [Chialvo: Fluid Phase Equilibria https://doi.org/10.1016/j.fluid.2017.10.031 and Journal of Chemical Physics, 148 (2018)]. We address the fundamentals underlying the isothermal-isobaric phase equilibria associated specifically with the solubility of carbon dioxide in aqueous systems, their thermodynamic limit of stability, as well as the link between the latter and the microstructure of the pair of incipient phases. Moreover, we show how the resulting equilibrium phase composition can provide relevant solvation quantities to test the thermodynamic consistency of the experimental data. Finally, we illustrate the arguments explicitly through the analysis of experimental evidence from a few selected sources in the literature, and discuss the implications behind the findings.

This study characterized steady state events (SS) in a semiarid reservoir (Brazil) dominated by cyanobacteria for 130 weeks, and evaluated the influence of different abiotic variables on their occurrence. It was hypothesized that, in semiarid reservoirs, steady state events are independent from seasonality and influenced by high nutrient concentrations, and steady state periods show low variation of species. Our data revealed the occurrence of SS events in both the dry and wet seasons. Higher concentrations of nitrate and sodium together with higher values of color favored the development of SS. Species composing the SS dominated by Microcystis aeruginosa (Kützing) Kützing was correlated with higher sulfate concentrations, while higher values of turbidity and sodium concentrations favored the SS of Cylindrospermopsis raciborskii (Woloszynska) Seenaya and Suba Raju and Planktothrix agardhii (Gomont) Anagnostidis and Komárek. The results supported the hypothesis and showed the importance of variables rarely evaluated in works of this nature, such as sodium and sulfate in SS establishment of cyanobacteria.

The sorbtion theory of components from inorganic and organic nature out of solutions on the boundary of hard substance-liquid phases has pure thermodynamic character. Adsorbing substance can be regarded as a special equilibrium phase having a limited volume, which can be characterized by entropy, enthalpy and energy of Gibbs. On the base of phenol and sulfonol sorbtion on the activated coal of KAD-iodine and anionite AB-17-OH out of waste waters with the variable concentration of sulphonyls from Sumgait plants Republic of Azerbaijan (at the interval 250–1000 mg/l) which many times exceeds MAC (0,1–5 mg/l), thermodynamic parameters of the process have been calculated: DS0, DH0, DG0. It’s well-known, that significance of enthalpy DH0 can be determined either from temperature dependence of contant equilibrium, or through the energy of diffusion activation, as the rate of sorbtional processes, including the activated coals and anionite of AB-17-OH in most cases is determined by diffusion of substances in pores of the sorbents framework. The significance of DH0 has been determined by the energy of diffusion activation according to the formula: DH0=Ea–RT, preliminary having calculated the data of effective coefficients of diffusion, which permitted us to make a conclusion that diffusional processes with phenol and sulfonol at the anionite AB-17-OH go much more slowly as compared with activated coal KAD-iodine. It has been established that G0 is reduced in all cases with the rise of filling in the sorbent surface. Besides, as compared with phenol, the adsorption of sulfonol on both sorbents enlarges with the rise of temperature, which is reflected by reducing DS0. In all cases the obtained data of DH0 tenfold lower than the data typical for chemosorbtional processes (80 kJ/mol) that correspond to mechanism of physical sorbtion.

The CO2-rich spring water (CSW) occurring naturally in three provinces, Kangwon (KW), Chungbuk (CB), and Gyeongbuk (GB) of South Korea was classified based on its hydrochemical properties using compositional data analysis. Additionally, the geochemical evolution pathways of various CSW were simulated via equilibrium phase modeling (EPM) incorporated in the PHREEQC code. Most of the CSW in the study areas grouped into the Ca-HCO3 water type, but some samples from the KW area were classified as Na-HCO3 water. Interaction with anorthite is likely to be more important than interaction with carbonate minerals for the hydrochemical properties of the CSW in the three areas, indicating that the CSW originated from interactions among magmatic CO2, deep groundwater, and bedrock-forming minerals. Based on the simulation results of PHREEQC EPM, the formation temperatures of the CSW within each area were estimated as 77.8 and 150 °C for the Ca-HCO3 and Na-HCO3 types of CSW, respectively, in the KW area; 138.9 °C for the CB CSW; and 93.0 °C for the GB CSW. Additionally, the mixing ratios between simulated carbonate water and shallow groundwater were adjusted to 1:9-9:1 for the CSW of the GB area and the Ca-HCO3-type CSW of the KW area, indicating that these CSWs were more affected by carbonate water than by shallow groundwater. On the other hand, mixing ratios of 1:9-5:5 and 1:9-3:7 were found for the Na-HCO3-type CSW of the KW area and for the CSW of the CB area, respectively, suggesting a relatively small contribution of carbonate water to these CSWs. This study proposes a systematic, but relatively simple, methodology to simulate the formation of carbonate water in deep environments and the geochemical evolution of CSW. Moreover, the proposed methodology could be applied to predict the behavior of CO2 after its geological storage and to estimate the stability and security of geologically stored CO2.

Composition optimization of Al-Zn-Mg-Cu alloys were systematically investigated by considering the precipitation strengthening and solid solution strengthening, based on thermodynamics and first-principles calculations. The calculated equilibrium phase diagram of Al-Zn-Mg-Cu alloy showed that Al-xZn-yMg-zCu (x = 4.8 ~ 6.3 wt%; y = 1.1 ~ 2.6 wt%; z = 1.6 ~ 3.1 wt%) alloys might contain five precipitates, including η-MgZn2, θ-Al2Cu, S-Al2CuMg, τ-Al2Mg3Zn3 and τ-Al6CuMg4. The first-principles calculated results indicated that θ-Al2Cu and S-Al2CuMg precipitates might be the dominated strengthening precipitates for the alloys. Then, the supercell models of the five solid solutions (Al67Zn2Mg2Cu, Al83Zn2Mg2Cu2, Al68ZnMg2Cu, Al64Zn3Mg4Cu and Al79Zn2Mg2Cu) were established according to the contents of θ-Al2Cu and S-Al2CuMg phases in the designed compositions, and followed the structural, elastic and electronic properties of these solid solutions were calculated. The calculated results showed that Al79Zn2Mg2Cu (Al-5.8 wt.%Zn-1.6 wt.%Mg-2.1 wt.%Cu) might present the optimal mechanical properties.

Rb2CeO3 compound was prepared by conventional solid-state reaction route. The Gibbs energy formation of the compound was determined by measuring the partial pressure of CO2 over the equilibrium phase mixture {Rb2CO3(s) + CeO2(s) + Rb2CeO3(s)} using Knudsen effusion quadrupole mass spectrometry. Gibbs energy formation of the compound, $$\Delta_{\text{f}} G_{\text{m}}^{o}$$ , as a function of temperature is obtained as: $$\Delta_{\text{f}} G_{\text{m}}^{\rm o} \left( {{\text{Rb}}_{2} {\text{CeO}}_{3} ,{\text{s}},T} \right)({\text{kJ}}\;{\text{mol}}^{ - 1} ) \, \left( { \pm 7} \right)\; = \; - 1601 + 0.41 \times \left( {T/K} \right)(991 \le T/K \le 1124)$$ The molar heat capacity of the compound, $$C^{\text o}_{\text{p,m}}$$ , was measured from 390 to 1100 K using a differential scanning calorimeter and is given as: $$C^{\rm o}_{\text{p,m}} \left( {{\text{Rb}}_{2} {\text{CeO}}_{3} ,{\text{s}},T} \right) \, ({\text{J}}\;{\text{mol}}^{ - 1} \;{\text{K}}^{ - 1} ) = 210.8 + 0.0061 \times \left( {T/K} \right){-}6348435/\left( {T/K} \right)^{2}$$ Based on these experimental data, thermodynamic table of the compound was also generated from 298.15 to 1000 K. Standard molar enthalpy of formation $$\Delta_{\text{f}} H_{\text{m}}^{\rm o}$$ (298.15 K) and standard molar entropy $$S_{\text{m}}^{\text o}$$ (298.15 K) of Rb2CeO3 are −1643 kJ mol−1 and 61.5 J K−1 mol−1, respectively.

The equilibrium phase diagram of the Zn(NO3)2–Ca(NO3)2–H2O system at 251.85, 262.35, and 288.15 K was studied by the isothermal solution saturation method and wet residue analysis. Densities of ternary Zn(NO3)2–Ca(NO3)2–H2O solutions were measured at 298.15–321.35 K. For some solutions, pH measurements were provided at 298.15 K.

The combination of new fuel compositions and higher burn-ups envisioned for the future means that representing fuel properties will be much more important, and yet more complex. Behavior within the oxide fuel rods will be difficult to model owing to the high temperatures, and the large number of elements generated and their significant concentrations that are a result of fuels taken to high burn-up. This unprecedented complexity offers an enormous challenge to the thermochemical understanding of these systems and opportunities to advance solid solution models to describe these materials. This paper attempts to model and simulate that behavior using an oxide fuels thermochemical description to compute the equilibrium phase state and oxygen potential of LWR fuel under irradiation.

The Ag-Zr and Cu-Zr binary systems are thermodynamically reassessed in this study. Not only phase diagrams, but also thermodynamic properties, such as enthalpy of formation for solids, activity for liquid, and enthalpy of mixing for liquid, are all calculated and compared with available experimental data to assure the accuracy of the assessment. Cu2Zr and Cu24Zr13 phases are considered as meta-stable phases, which would not exist in the Cu-Zr equilibrium phase diagram. The artifact of liquid miscibility gap at high temperature is avoided in the presently calculated phase diagrams.

To assess whether extracellular volume fraction (ECV) calculated from iodine(-blood) density images (I-B) of dual-energy liver CT (DECT) equilibrium phase data (EqD) is useful in estimating the degree of liver fibrosis. Consecutive 52 patients with chronic liver disease who underwent fast kV switching DECT and liver MR elastography (MRE) were retrospectively enrolled. Iodine(-water) density images (I-W) and I-B generated from EqD and ECV were calculated. As blood pools, abdominal aorta (Ao) and suprahepatic inferior vena cava (IVC) were chosen, and, therefore, 4 types of ECV (ECVI-W Ao, ECVI-W IVC, ECVI-B Ao, ECVI-B IVC) were obtained. ECV was also calculated using conventional method (ECVconv Ao). The correlation coefficients (R2 or rho) of these five ECVs versus liver stiffness (MRE) or pathologically proven fibrosis grades were compared. As for correlation with liver stiffness, R2 for ECVconv.Ao, ECVI-W Ao, ECVI-B Ao, ECVI-W IVC, and ECVI-B IVC, were 0.26, 0.34, 0.44, 0.39, and 0.52, respectively (all p

In order to figure out the high temperature ductility and industrial control technology of GH90, a systematic study was carried out by theoretical calculation, laboratory tests, and industrial experiments. The effect of major alloying element on equilibrium phase diagrams was calculated by Jmatpro and the effect of the element on high temperature ductility was theoretically analyzed, and the control of major element content was specified. In addition, hot compression test was carried out on thermo-simulator system Gleeble3500 at varying temperatures (900–1200 °C) and reduction ratio (10–70%). Based on above study, the hot forging and rolling technology was proposed and industrial experiment was carried out. The result showed that the deformation temperature was the main factor to influence the high temperature ductility of GH90 and the suitable deformation temperature is above 950 °C.

We have recently developed a simulation approach to calculate the equilibrium phase diagram of particle-based microphase formers. Here, this approach is used to calculate the phase behavior of the square-well linear model for different strengths and ranges of the linear long-range repulsive component. The results are compared with various theoretical predictions for microphase formation. The analysis further allows us to better understand the mechanism for microphase formation in colloidal suspensions.

The disposal of red mud, which is a solid waste that is generated during the extraction of alumina from bauxite, is one of major problems faced by the aluminum industry. Alkali in red mud seeping under the soil may pollute land and water. The Northeastern University, China, has proposed a calcification–carbonation method to deal with low-grade bauxite or red mud. Its main purpose is to change the equilibrium phase of red mud to 2CaO·SiO2 and CaCO3 hydrometallurgically, so that recomposed alkali-free red mud can be widely used. We conducted calcification transformation experiments using diasporic bauxite sampled from Wenshan, and investigated the effects of parameters such as diasporic bauxite grain size, temperature and treatment time on the calcification transformation digestion rate, which is also termed the calcification transformation rate (CTR). The main phase in the calcification transformation slag (CTS) is hydrogarnet with different grain sizes. The CTR increases with decrease in diasporic bauxite grain size, or increase in temperature or reaction time. The CTR reaches a maximum of 87% after 120 min reaction at 240°C. The Na2O/Al2O3 ratio decreases with increase in temperature and reaches 1.5. The sodium content in the CTS decreases with increasing reaction time and is lower than that in the red mud treated using the Bayer process (4–12%).

The atomic structure of the Al2Au η precipitate phase in an Al-0.2 at. %Au alloy is investigated using high-resolution scanning transmission electron microscopy together with first principles and elasticity theory calculations. We find experimentally that precipitates above a certain thickness exhibit the cubic crystal structure of the equilibrium phase η. However below that thickness precipitates adopt a tetragonal distortion of the cubic structure of η, which can be regarded as an intermediate η′ phase and allows full two-dimensional coherence for very thin precipitates (up to two unit cells' thick). Despite the structural similarities of the bulk structures of η and θ′ (Al2Cu) precipitate phases, the former displays interfacial structures that differ markedly from those recently observed in θ′. This can be attributed to the much lower defect energy in aluminium of solute Au compared with solute Cu. Both first-principles and elasticity theory calculations are in good agreement with our experimental observations.

International audience; Demixing can occur in systems of two or more particle species that experience different driving forces, e.g., mixtures of self-propelled active particles or of oppositely charged colloids subject to an electric field. Here we show with macroscopic experiments and computer simulations that the forces underlying such non-equilibrium segregation can be used to control the self-assembly of particles that lack attractive interactions. We demonstrate that, depending on the direction, amplitude and frequency of a periodic external force acting on one particle species, the structures formed by a second, undriven species can range from compact clusters to elongated, string-like patterns.

Special features of formation of phase composition in alloys of the Ti – Cr and Ti – Cr – H systems are studied after hardening from the β-range (according to the equilibrium phase diagram of the Ti – Cr system) and long-term aging. The morphology of the precipitated phases is determined and schemes explaining the special features of formation of phase composition in hydrogen-containing alloys under aging are suggested. The microhardness characteristics of the alloys are shown to depend on their phase composition.

Due to their different growth environments, the slagging problem of aquatic biomass such as microalgae Chlorella vulgaris (C. vulgaris) is different from that of other fuels such as wood, herbaceous biomass and wastes. Three sample groups of microalgae C. vulgaris were made into ash after different pretreatment processes: non-washing (NW), water-washing (WW) and acid-washing (AW). The slagging-predictive indices (SI), the ash fusibility temperatures (AFT) and ternary equilibrium phase diagram SiO2–CaO–K2O (SCK) system were applied separately to estimate the slagging tendency of aquatic biomass C. vulgaris, six terrestrial biomasses and six wastes. The results showed that the elemental composition of ash for C. vulgaris differed from that of other biofuels, especially regarding the content of P2O5. The WW and AW methods were effective for potassium and sulfur removal from C. vulgaris. The results from SI, AFT and SCK system showed that the three groups of C. vulgaris ash had high slagging tendency caused by the high phosphorus content. The results of SCK were consistent with the SI results of RB/A and RFu for biomass and wastes.

Full diameter core depletion tests are performed in this study to investigate the influence of depletion rate on the production of gas and condensate. Experimental results confirm that the gas recovery of the fast-depletion test is lower than that of the slow-depletion test. On the contrary, without the consideration of the fluid flow in porous media, the condensate recovery of the fast-depletion test is higher than that of the slow-depletion test. Non-equilibrium phase behavior is claimed to explain this abnormal behavior. The non-equilibrium model is adopted in this paper based on the components’ transfer rates between oil and gas phases. In addition, with the consideration of the compositional change in gas-condensate production, a numerical model is built to simulate the depletion process. Based on the comparison between the simulation and experimental results, the influence of non-equilibrium phase behavior on gas-condensate production is analyzed. If the depletion rate is relatively high, the heavy components of the gas-condensate system tend to be produced within the gas phase instead of condensing inside the core due to incomplete vapor-liquid separation. As a result, more condensate is acquired from the fast-depletion test.

Aluminum suppression of the α′ precipitate has been observed in eight model Fe–Cr–Al alloys with nominal compositions ranging from 11 to 20 wt% Cr and 4.5 to 6 wt% Al during long-term aging at 475 °C for up to 10,000 h. Fe–15Cr-4.5Al alloy reached the equilibrium state after aging for 10,000 h, in which the α′ phase evolution involved an integrated process of nucleation, growth, and coarsening. Meanwhile, no α-α′ phase separation occurred in the Fe–15Cr–6Al alloy during long-term aging at 475 °C. The α′ phase precipitated in the Fe–17Cr–6Al and Fe–20Cr–6Al alloys during the intermediate stage of aging, due to the inevitable composition fluctuation, and was eventually dissolved in the matrix in the later stages of aging. As such, a further increase in Al concentration (6 wt%) can strongly suppress the α′ precipitate in the equilibrium state. The equilibrium phase diagram of the Fe–Cr–Al system at 475 °C, which is based on the present work and previous literature, is expected to provide a more accurate reference for optimizing Fe–Cr–Al alloys for fuel cladding.

Energies of formation of binary Ni-containing compounds with NiAs (B8)-type structure were calculated using ab-initio density functional theory. Structural relaxations and calculation of the total energies of the binary structures NiX2 as CdI2-type structure, NiX as NiAs-type structure and Ni2X as Ni2In-type structure (with X= Al, Ga, In, Si, Ge, Sn, As, Sb, Bi, Se, Te) were done using the projector augmented wave (PAW) method with a generalised gradient approximation (GGA). Overall, the calculated values are in good agreement with comparable experimental literature data. General trends of the lattice parameters and the energies of formation are discussed in detail. Nearly all of the calculated compounds are thermodynamically stable compared to the elements at zero Kelvin, although not all of them are present in the equilibrium phase diagrams. According to a recent investigation of the system Ni–Sn–Te, continuous solid solutions from CdI2-type, over NiAs-type, up to Ni2In-type regions are possible. Hence, a modified sublattice model according to the compound energy formalism within Calphad is proposed to give this possibility consideration. The use of the calculated energies of formation at 0 K as endmember energies within this model is discussed.

Molar volume modeling was performed for both Ti-Al-Nb and Ti-Al-Mo ternary systems based on the thermodynamic modeling of these two systems. Comparison between the calculated phase equilibria and the experimental data proved the accuracy of thermodynamic modeling. With the calculated density contour curves superimposed on the equilibrium phase diagram, it provides a map for alloy developers to identify the promising alloy compositions that satisfy both the phase stability and density requirements and rule out those that fail to meet the requirements.

This paper presents thermodynamic modeling results for the magnesium reduction of the MgTa2O6, Mg4Ta2O9, and LiTaO3 tantalates. We have calculated the temperature-dependent heat capacity of the tantalates and determined the adiabatic temperature as a function of initial reactant temperature for reduction reactions in the MgTa2O6-5Mg, Mg4Ta2O9-5Mg, 2LiTaO3-5Mg, and 2LiTaO3-6Mg systems and the equilibrium phase composition of these systems.

In six-coordinate complexes, flexible tridentate ligands enable mer, cis-fac, and trans-fac stereoisomers. With labile metal ions of the first transition metal series, typically only the final thermodynamic product is available because of the rapid isomerization processes. Here we report on the structural characterization of a so far elusive kinetic intermediate of [Co(ddpd)2](BF4)2 (1; ddpd = N,N′-dimethyl-N,N′-dipyridine-2-yl-pyridine-2,6-diamine). Microcrystals of the cis-fac isomer of 1 were obtained by rapid precipitation. The solid-state structure of cis-fac-1 was determined from electron diffraction data.

A novel and pragmatic technique has been proposed to quantify the non-equilibrium phase behaviour together with physical properties of foamy oil under reservoir conditions. Experimentally, constant-composition expansion (CCE) experiments at various constant pressure decline rates are conducted to examine the non-equilibrium phase behaviour of solvent-CO2-heavy oil systems. Theoretically, the amount of evolved gas is firstly formulated as a function of time, and then incorporated into the real gas equation to quantify the non-equilibrium phase behaviour of the aforementioned systems. Meanwhile, theoretical models have been developed to determine the time-dependent compressibility and density of foamy oil. Good agreements between the experimentally measured volume-pressure profiles and calculated ones have been achieved, while both amounts of evolved gas and entrained gas as well as compressibility and density of foamy oil were determined. The time-dependent effects of entrained gas on physical properties of oleic phase were quantitatively analyzed and evaluated. A larger pressure decline rate and a lower temperature are found to result in a lower pseudo-bubblepoint pressure and a higher expansion rate of the evolved gas volume in the solvent-CO2-heavy oil systems. Apparent critical supersaturation pressure increases with either an increase in pressure decline rate or a decrease in system temperature. Physical properties of the oleic phase under non-equilibrium conditions follow the same trends as those of conventionally undersaturated oil under equilibrium conditions when pressure is higher than the pseudo-bubblepoint pressure. However, there is an abrupt increase of compressibility and decrease of density associated with pseudo-bubblepoint pressure instead of bubblepoint pressure due to the initialization of gas bubble growth. The amount of dispersed gas in the oleic phase is found to impose a dominant impact on physical properties of the foamy oil. Compared with CCE experiment at constant volume expansion rate, a rebound pressure and its corresponding effects on physical properties cannot be observed in the CCE experiments at constant pressure decline rate.

The present review will give a brief overview mainly focused on studies during the past 5 years on the mineral titanite (end-member composition CaTiSiO5) which could incorporate radioactive elements in its crystal structure. Aspects of investigations were the structural damage resulting from the radioactive decay, the thermally induced recrystallization process and the elastic properties of the mineral. During the radiation induced damage process, namely the metamictization, titanite becomes partially amorphous with coexisting defect enriched crystalline and aperiodic regions. Within these crystalline regions a P21/c to C2/c phase transition (∼ at 500 K) occurs. Resulting from radiation induced structural damage, titanite shows elastic properties close to those of titanite glass. During recrystallization on annealing an initial softening of the titanite structure takes place (up to temperature ∼950 K) resulting from the formation of soft interfaces. Thermal annealing at higher temperatures leads to increasing structural order and the hardening of the mineral.

Previous work showed that manganese ore reduction rates are strongly influenced by the extent of slag phase formation. In this work, the effect of ore composition on slag formation during manganese oxide reduction was predicted using thermochemical calculations; FactSage 6·4 was used to calculate the equilibrium phase relations in the oxide system MnO–SiO2–CaO–MgO–Al2O3. Practically observed differences in ore composition, even within the same orebody, are predicted to cause significant differences in slag formation during reduction, with large differences in ore reducibility expected.

Hafnium (Hf) is an important material for a wide range of applications including filaments, electrodes and control rods for nuclear reactors. Based on the equilibrium phase diagram, Hf exists in the form of a hexagonal closed-packed structure at temperature below 1743 °C or a body-centred cubic structure at temperature above 1743 °C. Here, we report the coexistence at ambient temperature of a hexagonal closed-packed structure, a body-centred cubic structure and a face-centred cubic structure with well-defined crystallographic orientation relationships in pure Hf produced by the iodide decomposition method.

We have studied the phase composition and crystal structure of CoSb x (1.82 ≤ x ≤ 4.16) nanofilms (30 nm) grown by molecular beam epitaxy on oxidized single-crystal silicon substrates at a temperature of 200°C, followed by heat treatment in vacuum at temperatures from 300 to 700°C. The as-grown films were found to be polycrystalline, with no preferential orientation. The effect of Sb content on the phase composition of the films was consistent with equilibrium phase diagram data for bulk Co-Sb materials. Vacuum annealing at temperatures above 450–500°C led to Sb sublimation not only from the crystalline phase but also from the antimonides, thereby increasing the percentages of the CoSb and CoSb2 phases and reducing the amount of CoSb3. The 30-nm-thick CoSb x (1.8 ≤ x ≤ 4.16) films were thermally stable at temperatures of up to 350°C.

Telluride misfit layer compounds are reported for the first time. These compounds were synthesized using a novel approach of structurally designing a precursor that would form the desired product upon low-temperature annealing, which allows the synthesis of kinetically stable products that do not appear on the equilibrium phase diagram. Four new compounds of the [(PbTe)1.17]m(TiTe2)n family are reported, and their structures were examined by a variety of X-ray diffraction techniques.

Although hot, cold, and high pressure denaturation are well characterized, the possibility of negative pressure unfolding has received much less attention. Proteins under negative pressure, however, are important in applications such as medical ultrasound, and the survival of biopoloymers in the xylem and adjacent parenchyma cells of vascular plants. In addition, negative pressure unfolding is fundamentally important in obtaining a complete understanding of protein stability and naturally complements previous studies of high pressure denaturation. We use extensive replica-exchange molecular dynamics (REMD) simulations and thermodynamic analysis to obtain folding/unfolding equilibrium phase diagrams for the miniprotein trp-cage (α-structure, 20-residue), the GB1 β-hairpin (β-structure, 16-residue), and the AK16 peptide (α-helix, 16-residue). Although the trp-cage is destabilized by negative pressure, the GB1 β-hairpin and AK16 peptide are stabilized by this condition.

The experimental studies on phase equilibria in the quaternary system Na+,K+//Cl–,B4O72––H2O at 323 K were done by the method of isothermal solution saturation. Solubilities of salts and densities of the solution were determined experimentally. The experimental results show that there is no double salt in the quaternary system Na+,K+//Cl–,B4O72––H2O at 323 K. The equilibrium phase diagram and the density-composition diagram were plotted based on the experimental data. In the phase diagram, the quaternary system has two invariant points, five univariant curves, and four crystallization fields corresponding to Na2B4O7·10H2O, K2B4O7·4H2O, NaCl, and KCl. A brief discussion of the experimental results is described.

The recently proposed mid-density scheme [Liu Z, Herrera L, Nguyen VT, Do DD, Nicholson D. A Monte Carlo scheme based on mid-density in a hysteresis loop to determine equilibrium phase transition. ...

Non-equilibrium phase transformation and effect of interfacial Li flux on miscibility gap in two-phase transformation of LiFePO4 have been explored in this study. Our previously developed “Mushy-Zone” (MZ) model, accounting for sluggish Li diffusion across the two-phase interface, has been employed to study the non-equilibrium phase transformation in LiFePO4 materials of Li-ion batteries. Phase transformation rate, variation of two-phase miscibility gap, and interfacial Li composition profiles have been studied for different particle shapes at varying discharge rates. Sluggish Li flux across the two-phase interface, which is believed to be the origin of the kinetically-induced non-equilibrium phase transformation, has been calculated to explain the obtained results. It is found that small particle sizes (radii of 20 nm) and slow discharge rates tend to create homogenous phase transformation (i.e., shrunk or no miscibility gap). Two-phase transformation is remarkably delayed for spherical particles at low discharge rates, leading to a lower capacity compared to that of plated-shaped particles. However, at higher discharge rates spherical particles show better capacity.

International audience; (Vapour + liquid) equilibrium (P-x-y) data are reported at three isotherms for the (propane + decafluorobutane), and (1-butene + decafluorobutane) binary systems. The range of temperatures extended from 312.92 K to 342.94 K. An apparatus based on the "static-analytic" method, which had two electromagnetic ROLSITM samplers, for repeatable and reliable equilibrium phase sampling and handling, was used to undertake the measurements. The experimental values were correlated with the "PR-MC-NRTL-WS" model which comprised the Mathias-Copeman alpha function, Wong-Sandler mixing rule, and NRTL local composition model which were incorporated into the Peng-Robinson equation of state. Maximum pressure azeotropy is observed for both systems at all investigated temperatures. Liquid-liquid immiscibility was not observed over the range of temperatures studied.