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High-temperature tensile properties of austenitic cast steels fabricated by replacing Ni by Mn in a 20 wt pct Ni-containing steel were investigated. In a steel where 8 wt pct Ni was replaced by 9.2 wt pct of Mn, 17.4 and 9.8 pct of ferrite existed in equilibrium phase diagrams and actual microstructures, respectively, because a role of Mn as an austenite stabilizer decreased, and led to deterioration of high-temperature properties. When 2 to 6 wt pct Ni was replaced by 2.3 to 6.9 wt pct Mn, high-temperature properties were comparable to those of the 20 wt pct Ni-containing steel because ferrites were absent, which indicated the successful replacement of 6 wt pct Ni by Mn, with cost reduction of 27 pct.

International audience; The recent success of immunotherapies for the treatment of cancer has highlighted the importance of the interactions between tumor and immune cells. Mathematical models of tumor growth are needed to faithfully reproduce and predict the spatiotemporal dynamics of tumor growth. We introduce a mathematical model intended to describe by means of a system of partial differential equations the early stages of the interactions between effector immune cells and tumor cells. The model is structured in size and space, and it takes into account the migration of the tumor antigen-specific cytotoxic effector cells towards the tumor micro-environment by a chemotactic mechanism. We investigate on numerical grounds the role of the key parameters of the model such as the division and growth rates of the tumor cells, and the conversion and death rates of the immune cells. Our main findings are two-fold. Firstly, the model exhibits a possible control of the tumor growth by the immune response; nevertheless, the control is not complete in the sense that the asymptotic equilibrium states keep residual tumors and activated immune cells. Secondly, space heterogeneities of the source of immune cells can significantly reduce the efficiency of the control dynamics, making patterns of remission-recurrence appear.

This paper deals with the issues related to the modeling of non-equilibrium phase transition in isothermal compositional models. Based on a real case of oil and gas field in the Middle East, the importance to take into account the effects of thermodynamic non-equilibrium are demonstrated with the help of mathematical models proposed earlier. Theoretical and experimental studies, as well as actual field development data, show that not all phase transition processes take place in the forward and reverse directions at the same rate. For example, the dissolution of gas is much slower than the gas liberation from oil. Non-equilibrium processes are those whose characteristic time is comparable to or exceeding the characteristic time of variation of external conditions. In the classical formulation, it is supposed that thermodynamic processes are equilibrium, but the effect of non-equilibrium in addition to large grid cell sizes of the dynamic model and small-time steps can significantly affect the simulation results. In the case of black oil models, there are extensions of the mathematical model that are often used to describe the non-equilibrium behavior. At the moment, the rate of establishment of thermodynamic equilibrium is not taken into account in the majority of compositional models, the neglection of which in some cases might question the reliability of the simulation results. The practical implementation of the ideas (Indrupskiy et al, 2017), which were stated about how to take into account the non-equilibrium of thermodynamic processes occurring in the reservoir for compositional models, is performed. The paper presents the results of modeling gas and water injection as a method of pressure support after development under depletion. In the equilibrium approach gas dissolves in oil at gas-oil contact simultaneously with increasing pressure. In practice, gas dissolution in oil occurs extremely slowly, and the dissolution rate decreases as the pressure approach the saturation pressure of the oil. According to laboratory studies, the modeling of such phase transitions requires the implementation of non-equilibrium models. At the same time, usage of the equilibrium models for this type of field leads to dramatic errors in estimates of the oil recovery.

Metastable materials that lie within the miscibility gaps of their equilibrium phase diagrams, as well as the development of lattice-parameter-engineered virtual substrates, offer means to greatly expand the material platforms available for semiconductor lasers to enable higher performance and an increased span of emission wavelengths.

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

Being a fatal threat to life, the breakdown of homeostasis in tissues is believed to involve multiscale factors ranging from the accumulation of genetic damages to the deregulation of metabolic processes. Here, we present a prototypical multicellular homeostasis model in the form of a two-dimensional stochastic cellular automaton with three cellular states, cell division, cell death and cell cycle arrest, of which the state-updating rules are based on fundamental cell biology. Despite the simplicity, this model illustrates how multicellular organizations can develop into diverse homeostatic patterns with distinct morphologies, turnover rates and lifespans without considering genetic, metabolic or other exogenous variations. Through mean-field analysis and Monte–Carlo simulations, those homeostatic states are found to be classified into extinctive, proliferative and degenerative phases, whereas healthy multicellular organizations evolve from proliferative to degenerative phases over a long time, undergoing a systematic ageing akin to a transition into an absorbing state in non-equilibrium physical systems. It is suggested that the collapse of homeostasis at the multicellular level may originate from the fundamental nature of cell biology regarding the physics of some non-equilibrium processes instead of subcellular details.

We explain theoretical peculiarities of the smectic-A-hexatic-B equilibrium phase coexistence in a finite-temperature range recently observed experimentally in free-standing smectic films [I. A. Zaluzhnyy et al., Phys. Rev. E 98, 052703 (2018)2470-004510.1103/PhysRevE.98.052703]. We quantitatively describe this unexpected phenomenon within Landau phase transitions theory assuming that the film state is close to a tricritical point. We found that the surface hexatic order diminishes the phase coexistence range as the film thickness decreases, shrinking it to zero at some minimal film thickness L_{c}, of the order of a few hexatic correlation length. We established universal laws for the temperature width of the phase coexistence range in terms of the reduced variables. Our theory is in agreement with the existing experimental data.

A fast time propagation method for nonequilibrium Green's functions based on the generalized Kadanoff--Baym Ansatz (GKBA) is applied to a lattice system with a symmetry-broken equilibrium phase, namely an excitonic insulator. The adiabatic preparation of a correlated symmetry-broken initial state from a Hartree--Fock wave function within GKBA is assessed by comparing with a solution of the imaginary-time Dyson equation. We find that it is possible to reach a symmetry-broken correlated initial state with nonzero excitonic order parameter by the adiabatic switching procedure. We discuss under which circumstances this is possible in practice within reasonably short switching times., 10 pages, 5 figures, Progress in Nonequilibrium Green's Functions VII proceedings

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.

Correction for ‘Phase mechanics of colloidal gels: osmotic pressure drives non-equilibrium phase separation’ by Lilian C. Johnson et al., Soft Matter, 2021, 17, 3784–3797, DOI: 10.1039/D0SM02180F.

Problems of unsteady gas-liquid flows in wellbores with phase transitions are common for hydrocarbon production and well drilling. Typically, flow in wellbores is sufficiently fast which requires taking into account the non-equilibrium nature of phase transitions. The set of equations describing conservation of mass for components and momentum conservation for the mixture is supplemented by the relaxation equation for concentration of gas dissolved in the liquid. It is known that the characteristic times of gas evolution from the liquid and gas dissolution in the liquid differ significantly and depend on fluid properties, thermobaric conditions, and the flow pattern. Therefore, obtaining estimates of relaxation times for real flows turns to be a difficult problem. In this study, we propose a method for estimating the characteristic relaxation times for gas evolution and dissolution during the gas-liquid flow in a well. The method combines the solution of the convective diffusion equation for the growth/collapse of a vapor bubble in a liquid with the current parameters of the gas-liquid flow. Estimates of the relaxation times for the bubbly flow (small bubbles, gas evolution predominates) and slug flow (large bubbles, dissolution predominates), as functions of time from the beginning of the process, are obtained for the parameters of a real flow in a wellbore. It is shown that the obtained dependencies are consistent with the typical scaling of the diffusion process with respect to the size of bubbles. The results are important for mathematical simulation of gas-liquid flows in wellbores during hydrocarbon production, as well as for calculation of the gas-kick process during well drilling with oil-based muds.

To compare abdominal equilibrium phase (EP) CT images of obese and non-obese patients to identify the reconstruction method that preserves the diagnostic value of images obtained in obese patients.We compared EP images of 50 obese patients whose body mass index (BMI) exceeded 25 (group 1) with EP images of 50 non-obese patients (BMI 25, group 2). Group 1 images were subjected to deep learning reconstruction (DLR), hybrid iterative reconstruction (hybrid-IR), and model-based IR (MBIR), group 2 images to hybrid-IR; group 2 hybrid-IR images served as the reference standard. A radiologist recorded the standard deviation of attenuation in the paraspinal muscle as the image noise. The overall image quality was assessed by 3 other radiologists; they used a confidence scale ranging from 1 (unacceptable) to 5 (excellent). Non-inferiority and potential superiority were assessed.With respect to the image noise, group 1 DLR- were superior to group 2 hybrid-IR images; group 1 hybrid-IR- and MBIR images were neither superior nor non-inferior to group 2 hybrid-IR images. The quality scores of only DLR images in group 1 were superior to hybrid-IR images of group 2 while the quality scores of group 1 hybrid-IR- and MBIR images were neither superior nor non-inferior to group 2 hybrid-IR images.DLR preserved the quality of EP images obtained in obese patients.

Clusters of aligned, highly elongate, prismatic quartz (Qtz) rods occur in a few fayalite (Fa) crystals in an eulysite from a recently identified ∼1.8 Gy UHP site in central West Greenland (Glassley et al. 2014). Additional detailed analyses of the crystallography and phase compositions of these olivines were conducted to evaluate the postulate that the Qtz rods formed during inversion of super-silicic ahrensite to Fa+Qtz during decompression. These new observations show the Qtz rods consistently occur in crystallographically coherent clusters with the Qtz grains aligned parallel to [100] of Fa. The contrasting compositions of coexisting primary UHP Fa and Fa postulated to have formed by inversion of ahrensite are consistent with the inversion scenario. We thus conclude that all available data are consistent with the postulate that ahrensite was part of the equilibrium phase assemblage formed during UHP metamorphism and that it inverted to Fa+Qtz upon decompression. If true, this would represent the first occurrence of terrestrial ahrensite formed through natural tectonic processes.

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.

The present work is devoted to the modelling which is based on the modified Cahn-Hilliard equation, the interplay of equilibrium and non-equilibrium phase transitions. The non-equilibrium phase transitions are modelled by the Schl\"ogl reactions systems. We consider the advancing fronts which combine these both transitions. The traveling wave solutions are obtained; the conditions of their existence and dependence on the parameters of the models are studied in detail. The possibility of the existance of non-equilibrated phase is discussed., Comment: 17 pages, 2 figures

N point particles move within a billiard table made of two circular cavities connected by a straight channel. The usual billiard dynamics is modified so that it remains deterministic, phase space volumes preserving and time reversal invariant. Particles move in straight lines and are elastically reflected at the boundary of the table, as usual, but those in a channel that are moving away from a cavity invert their motion (rebound), if their number exceeds a given threshold T. When the geometrical parameters of the billiard table are fixed, this mechanism gives rise to non--equilibrium phase transitions in the large N limit: letting T/N decrease, the homogeneous particle distribution abruptly turns into a stationary inhomogeneous one. The equivalence with a modified Ehrenfest two urn model, motivated by the ergodicity of the billiard with no rebound, allows us to obtain analytical results that accurately describe the numerical billiard simulation results. Thus, a stochastic exactly solvable model that exhibits non-equilibrium phase transitions is also introduced.

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.

The microstructure of a Cu-0.13 wt%Zr alloy cast or aged at 450–950 °C for 1 min–30 days (d) after solutionizing was investigated. Spherical fine precipitates having an ordered fcc lattice with a = 0.416 nm and a cube-on-cube orientation relationship to the Cu matrix were newly found in the cast alloy. Aging the alloy at 450 and 500 °C up to 30 d produced only disk-shaped Cu5Zr precipitates. In addition to the disk-shaped precipitates, the fine ordered fcc precipitates were formed in the alloy aged at 600–850 °C for a short time. The alloy aged at 900–950 °C for 1 min showed the coexistence of the fine fcc precipitates and coarse rod-shaped Cu5Zr precipitates of the equilibrium phase. Even after prolonged aging for 7–14 d at 600–950 °C, the fine fcc precipitates still remained together with the rod-shaped Cu5Zr precipitates of the equilibrium phase, indicating that the fcc precipitated phase is fairly stable at 600–950 °C. The aging time dependences of electrical resistivity at temperatures between 600 and 950 °C allowed us to obtain the solid solubility limits at these temperatures. The obtained solvus is coincident with the data reported previously.

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.

Phase stability of a mixture at given conditions is studied. The modelling of equilibrium phase compositions is considered when the original phase of the mixture is unstable. The tangent plane distance criterion is used for stability analysis and the Gibbs energy minimisation is employed for phase equilibrium calculation when the successive substitution does not work well. With the Helmholtz free energy equation of state, thermodynamic properties in single phase and two-phase equilibrium were calculated for methane-ethane mixtures. Phase envelopes were also calculated.

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.

We investigate nonequilibrium phase transitions in classical Heisenberg spin chains associated with spontaneous breaking of parity-time ($\mathcal{PT}$) symmetry of the system under the action of Slonczewski spin-transfer torque (STT) modeled by an applied \textit{imaginary} magnetic field. We reveal the STT-driven $\mathcal{PT}$ symmetry-breaking phase transition between the regimes of precessional and exponentially damped spin dynamics and show that its several properties can be derived from the distribution of zeros of the system's partition function, the approach first introduced by Yang and Lee for studying equilibrium phase transitions in Ising spin chains. The physical interpretation of imaginary magnetic field as describing the action of non-conservative forces opens the possibility of direct observations of Lee-Yang zeros in nonequilibrium physical systems., 5 pages, 4 figures

Density-functional theory calculations have been performed to systematically investigate the behaviors of solute atoms in 7000 series Al–Zn–Mg based alloys. It is found that solute atoms Mg and Zn are likely to segregate to the Σ5(210)[001] tilt Al GB. The bonding environment and interface cohesion will be affected to different degrees. Also, for GPI(100) our calculations indicate that a Zn/Mg/Zn sandwich configuration in the Al matrix (100) planes is energetically favorable. However, for GPII(111) the disordered structure turns out to be the most stable one. It mainly results from strong 3d–3s hybridization interactions between Zn and Mg atoms. Furthermore, the properties of the metastable phase η′ and the equilibrium phase η have also been addressed. The present study provides valuable insight for developing Al alloys with superior performance.

Objectives To assess whether extracellular volume fraction (ECV) obtained from routine liver CT equilibrium phase data utilizing new subtraction algorithm is useful in estimating the degree of liver fibrosis. Materials and methods Consecutive 41 patients, 21 men and 20 women, with chronic liver diseases who underwent quadri-phase liver CT and MR elastography within 3 months were retrospectively enrolled. Subtraction image of unenhanced from equilibrium phase (240 s) images using conventional and new algorithms were made. We firstly assessed the quality of these subtraction algorithms using patients in whom anatomical misregistration between the two image sets were prominent. Then, ECVs were calculated using both subtraction data sets (ECV-convSub, and ECV-newSub, respectively). ECV were also calculated by traditional manual method (ECV-man). Correlation coefficients of 3 types of ECV were compared using liver stiffness (kPa) as measured by MR elastography and pathologically proven fibrosis grades as reference standards. Results For eleven patients with prominent anatomical misregistration between the unenhanced and equilibrium phases, new algorithm provided significantly better subtraction images than the conventional one (p = 0.001, Wilcoxon’s signed rank test). As for correlation with liver stiffness, R2 for ECV-man, ECV-convSub, and ECV-newSub, were 0.57, 0.59, and 0.66, respectively (all p Conclusion ECV-newSub showed better correlation to liver stiffness and pathological fibrosis grades than ECV-convSub and ECV-man, which could be a reliable biomarker of liver fibrosis obtained from routine clinical diagnostic imaging data, where equilibrium phase delay time was set at 240 s.

We show that resonance phenomena can be treated as nonequilibrium phase transitions. Resonance phenomena, similar to equilibrium phase transitions, are accompanied by some kind of symmetry breaking and can be characterized by order parameters. This is demonstrated for spin-wave resonance, helicon resonance, and spin-reversal resonance.

Several aspects of anelastic behavior of Fe-(27-28%)Ga-Tb alloys are considered in this paper: (i) the phase transitions from a metastable to an equilibrium phase and phase transitions between equilibrium phases at higher temperatures in as cast alloys, (ii) the nature of corresponding three transient anelastic effects, (iii) the formation of an intrinsic composite microstructure with a different ratio between the bcc-derivative metastable and fcc-derivative equilibrium phases that have different magnetostriction and the effect of alloys doping by Tb to stabilize the metastable phase with high positive values of magnetostriction.

Thermodynamic calculation of the equilibrium phase composition and evolution of the size and composition of carbide particles was carried out using Thermo-Calc and TC-Prisma 2.0 in order to identify the optimal modes of the final heat treatment for 15H2NMFA and 26HN3M2FA steels. The formation of structure and mechanical properties complex of the investigated steels was experimentally studied after tempering. The model describing the precipitation and growth of carbide particles was suggested based on the experimental results. This model will be used as part of the developed control complex of thermodynamic and kinetic conditions for the formation of micro grains and nano-sized hardening phases.

We study simple models of intermittency, involving switching between two states, within the dynamical large-deviation formalism. Singularities appear in the formalism when switching is cooperative, or when its basic timescale diverges. In the first case the unbiased trajectory distribution undergoes a symmetry breaking, leading to a change of shape of the large-deviation rate function for a particular dynamical observable. In the second case the symmetry of the unbiased trajectory distribution remains unbroken. Comparison of these models suggests that singularities of the dynamical large-deviation formalism can signal the dynamical equivalent of an equilibrium phase transition, but do not necessarily do so.

The objective of this study is to experimentally and theoretically investigate the phase stability of non-equiatomic FexMn62−xNi30Co6Cr2 based high entropy alloys, where x ranges from 22 to 42 at.%. Another aim is to systematically and critically assess the predictive capability of the CALPHAD approach for such high entropy alloy systems. We find that the CALPHAD simulations provide a very consistent assessment of phase stability yielding good agreement with experimental observations. These include the equilibrium phase formation at high temperatures, the constituent phases after non-equilibrium solidification processes, unfavorable segregation profiles inherited from solidification together with the associated nucleation and growth of low temperature phases, and undesired martensitic transformation effects. Encouraged by these consistent theoretical and experimental results, we extend our simulations to other alloy systems with equiatomic compositions reported in the literature. Using these other equiatomic model systems we demonstrate how systematic CALPHAD simulations can improve and accelerate the design of multicomponent alloy systems.

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.

The ordered ω phases in high Nb containing TiAl (Nb-TiAl) alloys have been garnering increasing attention in the recent years. However, the investigations on the Nb dependence on the ω o precipitation are scarce. In this study, the effect of Nb content on the ω o precipitation in high Nb (6–10 at%) containing TiAl alloys after long-time annealing at 850 °C has been studied. The results show that small ordered ω particles in the retained β o phase cannot be discerned under scanning electron microscope (SEM) but can be observed using transmission electron microscopy (TEM). Although the Nb segregation can be eliminated after the homogenization heat treatment, the ω o phase precipitated in all the alloys studied after annealing at 850 °C. TEM examination reveals that the orientation relationship between the ω o and α 2 phases can be derived as: [0001] ω o //[1120] α 2 ; (1120) ω o //(0001) α 2 , which indicates that the ω o phase is directly transformed from the parent α 2 phase. Small γ particles are also observed within the ω o areas. The α 2 → ω o + γ decomposition process is expected during annealing. It is concluded that ω o phase is an equilibrium phase in high Nb-TiAl alloys at 850 °C.

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.

The new type dynamic phase diagrams and the non-equilibrium lever principle of carbon steel have been established and discussed, the corresponding structures and chemical compositions are analyzed. The computer calculation programming of phase diagram and main computer program have been setted.

Despite many attempts, ordered equilibrium microphases have yet to be obtained in experimental colloidal suspensions. The recent computation of the equilibrium phase diagram of a microscopic, particle–based microphase former [Zhuang et al., Phys. Rev. Lett. 116, 098301 (2016)] has nonetheless found such mesoscale assemblies to be thermodynamically stable. Here, we consider their equilibrium and assembly dynamics. At intermediate densities above the order-disorder transition, we identify four different dynamical regimes and the structural changes that underlie the dynamical crossovers from one disordered regime to the next. Below the order-disorder transition, we also find that periodic lamellae are the most dynamically accessible of the periodic microphases. Our analysis thus offers a comprehensive view of the dynamics of disordered microphases and a route to the assembly of periodic microphases in a putative well-controlled, experimental system.

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.

We introduce a model of interacting lattices at different resolutions driven by the two-dimensional Ising dynamics with a nearest-neighbor interaction. We study this model both with tools borrowed from equilibrium statistical mechanics as well as non-equilibrium thermodynamics. Our findings show that this model keeps the signature of the equilibrium phase transition. The critical temperature of the equilibrium models corresponds to the state maximizing the entropy and delimits two out-of-equilibrium regimes, one satisfying the Onsager relations for systems close to equilibrium and one resembling convective turbulent states. Since the model preserves the entropy and energy fluxes in the scale space, it seems a good candidate for parametric studies of out-of-equilibrium turbulent systems.

Phase equilibria of the Na,K,Mg,Ca‖SO4,Cl-H2O system at 50°C in the halite (NaCl) crystallization field were studied using the translation method. Halite, which is an equilibrium phase of the title system at 50°C, was found to be involved in 25 invariant points, 59 monovariant curves, and 43 divariant fields. A fragment of the equilibrium phase diagram of the title system in the halite crystallization field was constructed.