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We present the explicit bonding Reaction ensemble Monte Carlo (eb-RxMC) method, designed to sample reversible bonding reactions in macromolecular systems in thermodynamic equilibrium. Our eb-RxMC method is based on the reaction ensemble method; however, its implementation differs from the latter by the representation of the reaction. In the eb-RxMC implementation, we are adding or deleting bonds between existing particles, instead of inserting or deleting particles with different chemical identities. This new implementation makes the eb-RxMC method suitable for simulating the formation of reversible linkages between macromolecules, which would not be feasible with the original implementation. To enable coupling of our eb-RxMC algorithm with molecular dynamics algorithm for the sampling of the configuration space, we biased the sampling of reactions only within a certain inclusion radius. We validated our algorithm using a set of ideally behaving systems undergoing dimerization and polycondensation reactions, for which analytical results are available. For dimerization reactions with various equilibrium constants and initial compositions, the degree of conversion measured in our simulations perfectly matched the reference values given by the analytical equations. We also showed that this agreement is not affected by the arbitrary choice of the inclusion radius or the stiffness of the harmonic bond potential. Next, we showed that our simulations can correctly match the analytical results for the distribution of the degree of polymerization and end-to-end distance of ideal chains in polycondensation reactions. Altogether, we demonstrated that our eb-RxMC simulations correctly sample both reaction and configuration spaces of these reference systems, opening the door to future simulations of more complex interacting macromolecular systems. [ABSTRACT FROM AUTHOR]

Colloidal building blocks with re-configurable shapes and dynamic interactions can exhibit unusual self-assembly behaviors and pathways. In this work, we consider the phase behavior of colloids coated with surface-mobile polymer brushes that behave as "dynamic surfactants." Unlike traditional polymer-grafted colloids, we show that colloids coated with dynamic surfactants can acquire anisotropic macroscopic assemblies, even for spherical colloids with isotropic attractive interactions. We use Brownian Dynamics simulations and dynamic density functional theory to demonstrate that time-dependent reorganization of the dynamic surfactants leads to phase diagrams with anisotropic assemblies. We observed that the microscopic polymer distributions impose unique geometric constraints between colloids that control their packing into lamellar, string, and vesicle phases. Our work may help discover versatile building blocks and provide extensive design freedom for assembly out of thermodynamic equilibrium. [ABSTRACT FROM AUTHOR]

Clathrate hydrates are crystals formed by guest molecules that stabilize cages of hydrogen-bonded water molecules. Whereas thermodynamic equilibrium is well described via the van der Waals and Platteeuw approach, the increasing concerns with global warming and energy transition require extending the knowledge to non-equilibrium conditions in multiphase, sheared systems, in a multiscale framework. Potential macro-applications concern the storage of carbon dioxide in the form of clathrates, and the reduction of hydrate inhibition additives currently required in hydrocarbon production. We evidence porous mesomorphologies as key to bridging the molecular scales to macro-applications of low solubility guests. We discuss the coupling of molecular ordering with the mesoscales, including (i) the emergence of porous patterns as a combined factor from the walk over the free energy landscape and 3D competitive nucleation and growth and (ii) the role of molecular attachment rates in crystallization–diffusion models that allow predicting the timescale of pore sealing. This is a perspective study that discusses the use of discrete models (molecular dynamics) to build continuum models (phase field models, crystallization laws, and transport phenomena) to predict multiscale manifestations at a feasible computational cost. Several advances in correlated fields (ice, polymers, alloys, and nanoparticles) are discussed in the scenario of clathrate hydrates, as well as the challenges and necessary developments to push the field forward. [ABSTRACT FROM AUTHOR]

A fundamental equation of state in terms of the Helmholtz energy is presented for mixtures of nitrogen, oxygen, and argon at any composition. It is expressed in terms of the residual Helmholtz energy and can be used to calculate all thermodynamic equilibrium properties including vapor–liquid equilibria. The parameters of the equations for the pure-fluid and mixture contributions are fitted exclusively to molecular simulation data so that the model has a predictive character. The description of the mixture-specific reducing parameters is realized via generalized correlations of the critical parameters of the pure fluids so that an extension of the model to additional components can be implemented straightforwardly. Extensive comparisons to experimental data and the GERG-2008 reference equation of state show that the prediction of thermodynamic properties is satisfactory. [ABSTRACT FROM AUTHOR]

Vapor–liquid equilibria and thermodynamic properties of saturated argon and krypton were calculated by semi-classical Monte Carlo simulations with the NpT + test particle method using ab initio potentials for the two-body and nonadditive three-body interactions. The NpT + test particle method was extended to the calculation of second-order thermodynamic properties, such as the isochoric and isobaric heat capacities or the speed of sound, of the saturated liquid and vapor by using our recently developed approach for the systematic calculation of arbitrary thermodynamic properties in the isothermal–isobaric ensemble. Generally, the results for all simulated properties agree well with experimental data and the current reference equations of state for argon and krypton. In particular, the results for the vapor pressure and for the density and speed of sound of the saturated liquid and vapor agree with the most accurate experimental data for both noble gases almost within the uncertainty of these data, a level of agreement unprecedented for many-particle simulations. This study demonstrates that the vapor–liquid equilibrium and thermodynamic properties at saturation of a pure fluid can be predicted by Monte Carlo simulations with high accuracy when the intermolecular interactions are described by state-of-the-art ab initio pair and nonadditive three-body potentials and quantum effects are accounted for. [ABSTRACT FROM AUTHOR]

We develop a model for the thermodynamics and evaporation dynamics of aerosol droplets of a liquid, such as water, surrounded by gas. When the temperature and the chemical potential (or equivalently the humidity) are such that the vapor phase is in the thermodynamic equilibrium state, then, of course, droplets of the pure liquid evaporate over a relatively short time. However, if the droplets also contain nanoparticles or any other non-volatile solute, then the droplets can become thermodynamically stable. We show that the equilibrium droplet size depends strongly on the amount and solubility of the nanoparticles within, i.e., on the nature of the particle interactions with the liquid and, of course, also on the vapor temperature and chemical potential. We develop a simple thermodynamic model for such droplets and compare predictions with results from a lattice density functional theory that takes as input the same particle interaction properties, finding very good agreement. We also use dynamical density functional theory to study the evaporation/condensation dynamics of liquid from/to droplets as they equilibrate with the vapor, thereby demonstrating droplet stability. [ABSTRACT FROM AUTHOR]

Equilibrium thermodynamics describes the energy exchange of a body with its environment. Here, we describe the global energy exchange of an ideal gas in the Coutte flow in a thermodynamic-like manner. We derive a fundamental relation between internal energy as a function of parameters of state. We analyze a non-equilibrium transition in the system and postulate the extremum principle, which determines stable steady states in the system. The steady-state thermodynamic framework resembles equilibrium thermodynamics. [ABSTRACT FROM AUTHOR]

Freezing of water under nanoconfinement exhibits physical peculiarities with respect to the bulk water. However, experimental observations are extremely challenging at this scale, which limits our understanding of the effect of confinement on water properties upon freezing. In this study, we use molecular dynamic simulations to investigate how confinement affects the kinetics of growth of ice and the thermodynamic equilibrium of ice-liquid coexistence. TIP4P/Ice water model and CSH-FF model were applied to simulate ice crystallization in a confined cement system at temperatures down to 220 K. We adapted an interface detection algorithm and reparameterized the CHILL/CHILL+ algorithm to capture ice growth. The confinement leads to a shift of the maximum growth rate of ice to a higher temperature than for bulk water. Both the confinement and surface impurities contribute to slowing down the ice growth. For the ice-liquid coexistence at equilibrium, we derive a formulation of Thomson's equation adapted to statistical physics quantities accessible by molecular simulation, and we show that this adapted equation predicts accurately the melting line of bulk and confined ice Ih as a function of pressure. The confinement decreases systematically the melting temperature of ice of about 5 K compared with bulk ice Ih. A premelted water film about 1 nm thick is observed between the solid wall and ice, and its thickness is found to decrease continuously as temperature is lowered. We note that the surface impurities are key to the formation of the premelted water nanofilm when the temperature is lower than 250 K. [ABSTRACT FROM AUTHOR]

Chemically driven fluids can demix to form condensed droplets that exhibit phase behaviors not observed at equilibrium. In particular, nonequilibrium interfacial properties can emerge when the chemical reactions are driven differentially between the interior and exterior of the phase-separated droplets. Here, we use a minimal model to study changes in the interfacial tension between coexisting phases away from equilibrium. Simulations of both droplet nucleation and interface roughness indicate that the nonequilibrium interfacial tension can either be increased or decreased relative to its equilibrium value, depending on whether the driven chemical reactions are accelerated or decelerated within the droplets. Finally, we show that these observations can be understood using a predictive theory based on an effective thermodynamic equilibrium. [ABSTRACT FROM AUTHOR]

This work investigates the hydrogen embrittlement (HE) behavior of Nickel-201 alloy using experimental and numerical approaches. In experimentation, the effect of electrochemical hydrogen charging on the deformation behavior of tensile oligocrystals is investigated at different strain rates. Irrespective of the strain rate levels, all the hydrogen-charged tensile oligocrystals exhibited intergranular (IG) fracture exclusively along the random high-angle grain boundaries (RHAGBs). At the same time, no crack was observed along the coincident site lattice (CSL) Σ 3 type grain boundaries. The absence of an interconnected grain boundary network, lower stress levels, and insensitivity of H-induced IG fracture to the strain rate levels of investigated FCC oligocrystals (with low lattice hydrogen diffusion coefficient) established the insignificance of dynamic H-redistribution toward HE. In numerical simulations, a crystal plasticity-phase field fracture finite element model simulates the macroscopic tensile response and corresponding microscopic fracture evolution behavior for hydrogen-free and hydrogen-charged tensile oligocrystals. The experimental results corroborated by numerical simulations, validate that the reduction in fracture energy of RHAGBs, induced by hydrogen segregation through thermodynamic equilibrium during hydrogen charging prior to deformation, is the dominating factor governing HE. • Hydrogen embrittlement (HE) of Ni- oligocrystals at various strain rate is investigated. • Experimental results are corroborated by crystal plasticity-phase field fracture simulations. • H-induced intergranular fracture initiated and propagated along the RHAGBs only. • H-segregation by thermodynamic equilibrium established prior to deformation governs the HE. [ABSTRACT FROM AUTHOR]

Magnetic graphene hybrid has encouraging application in environmental remediation. Herein, adsorption-reduction behavior of Cr (Ⅵ) on Fe 3 O 4 -graphene oxide (Fe 3 O 4 -GO) surface was inspected via both theoretical and experimental methods. In the theoretical level, acidity impact on Cr (Ⅵ) species evolution and Cr (Ⅵ)→Cr (Ⅲ) reduction was investigated with the methodology of equilibrium thermodynamics. In the experimental level, adsorption fittings and spectroscopic tests (FTIR, UV–Vis, XPS) were performed to clarify the adsorbent-adsorbate interaction. Results indicate: (1) Under acidic condition, Cr (Ⅵ) is adsorbed by Fe 3 O 4 -GO in the form of H 2 CrO 4. Afterwards, over three-fifths of H 2 CrO 4 is reduced to Cr (Ⅲ), reaching adsorption percent and quantity 95.53 % and 382.10 mg g−1 in 10 min (2) Under basic condition, Cr (Ⅵ) is adsorbed in the form of CrO 4 2− without reduction. In the context of environmental remediation, two special implications are thereby procured. (1) Under acidic condition, Cr (Ⅵ) removal efficiency at the first cycle is maximized, while magnetic recovery is deteriorated, resulting in unsatisfactory cyclic performance. (2) Under basic condition, Cr (Ⅵ) removal efficiency is inferior to that under acidic condition, while magnetic recovery is guaranteed, leading to satisfactory cyclic performance. Exploration of this work provides reference especially for developing Fe 3 O 4 -GO architecture towards efficient sequestering of hexavalent chromium. Adsorption-reduction behavior of Cr (Ⅵ) on Fe 3 O 4 -GO surface(a) Illumination of redox reaction between Cr (Ⅵ) and Fe 3 O 4 given by thermodynamic calculation. Under acidic condition: spontaneous reaction H2CrO4+3Fe 2+ +6H + ⇌Cr 3+ +3Fe 3+ +4H2O owing to highly negative standard molar Gibbs free energy change. Under basic condition, non spontaneous reaction CrO4 2− +3Fe 2+ +4H2O⇌Cr(OH)4 - +3Fe 3+ +4OH − owing to highly positive standard molar Gibbs free energy change. (b) Adsorption-reduction behavior of Cr (Ⅵ) on Fe 3 O 4 -GO surface deciphered by Cr (Ⅵ) species distribution and XPS test. Under acidic condition: five small orange balls symbolizing H 2 CrO 4 adsorbed onto the surface of the big green ball representing Fe 3 O 4 -GO. Subsequently, three out of five small orange balls were transformed into small violet balls representing Cr3+, approaching the molar ratio Cr (Ⅲ)/Cr (Ⅵ) = 1.52 of the sample Fe 3 O 4 -GO-Cr as determined by XPS test (Fig. 8). The big blue ball represents Fe 3 O 4 -GO oxidized by H 2 CrO 4. Under basic condition: five small pink balls symbolizing CrO 4 2− adsorbed onto the surface of the big green ball representing Fe 3 O 4 -GO ensued by no reduction, as confirmed by thermodynamic analysis. [Display omitted] • Adsorption-reduction behavior of Cr (Ⅵ) on Fe 3 O 4 -graphene oxide surface is inspected. • In acidic media, H 2 CrO 4 is adsorbed, three-fifths of which is reduced to Cr (Ⅲ). • In basic media, CrO 4 2− is adsorbed without reduction. • Superior Cr (Ⅵ) removal efficiency but unsatisfactory cyclic performance in acidic media. [ABSTRACT FROM AUTHOR]

• The effect of temperature on plasma gasification of CPMW is explored experimentally. • A temperature of 1800 °C provides the optimum performance for air-CPMW gasification. • The volume fraction of H 2 and CO increases with the increased reactor temperature. Plasma gasification melting (PGM) provides reliable disposal of toxic medical waste with a low heating value, which is capable of converting waste into energy. This study investigates the performance of experiments on plasma gasification for the treatment of chemical-pharmaceutical medical waste (CPMW) with an air medium. A comparative analysis is performed for gasification characteristics at three reactor temperatures (1000, 1400, and 1800 °C). Moreover, a thermodynamic equilibrium model is developed to assess performance features such as syngas yield, high heating value, and cold gas efficiency in the gasification temperature range of 1000–1800 °C. A comparison of the experiment and computational outcomes shows a good agreement. The results show that the quality of syngas and heating value is improved by increasing the temperature of the plasma gasifier so that at 1800 °C, H 2 , CO, and higher heating value (HHV) are obtained as 41 %, 37 %, and 10 MJ/Nm3, respectively. The obtained syngas is a clean fuel with low sulfur-containing and nitrogen-containing. The experimental results provide an extensive comprehension of CPMW gasification in a plasma reactor and consider a possibility for hydrogen and energy production. [ABSTRACT FROM AUTHOR]

The limited velocity in a geometry of Lorentzian signature seem to prevent the universe to reach thermodynamic equilibrium as suggested by the cosmic microwave background. Thus it was suggested that the universe which was initially minuscule has reached a more considerable radius in a short duration by a process known as cosmic inflation. However, to drive such a process have led to the suggestion of an ad-hoc scalar field the inflaton, which has no purpose in nature other than driving the cosmic inflation field and then stopping it once the universe reached the right size. In a recent paper it was shown that rapid expansion can occur without postulating an inflation by following Hawking's suggestion and assuming that primordially the metric of the universe had an Euclidean signature, in which case velocity is not limited and thermalization and rapid expansion are derived without the need to assume an ad-hoc field. However, while in the previous work emphasis was put on the dynamics and physical statistics of the particles in a Euclidean space versus Lorentzian space in which both spaces were given. No mathematical model was given regarding the development of current Lorentzian space-time from the early Euclidean space-time, and how fundamental problems such as the space-time singularity and the homogeneity of the CMB can be solved in the hybrid Euclidean–Lorentzian picture. This lacuna is to be rectified in this paper. [ABSTRACT FROM AUTHOR]

Thorium biosorption by a green microalga, Chlorella Vulgaris, was studied in a stirred batch reactor to investigate the effect of initial solution pH, metal ion concentration, biomass dosage, contact time, kinetics, equilibrium and thermodynamics of uptake. The green microalgae showed the highest Th adsorption capacity at 45 °C for the solution with a thorium concentration of 350 mg L−1 and initial pH of 4. The amount of uptake raised from 84 to 104 mg g−1 as the temperature increased from 15 to 45 °C for an initial metal concentration of 75 mg L−1 at pH 4. Transformation Infrared Spectroscopy (FTIR) was employed to characterize the vibrational frequency changes for peaks related to surface functional groups. Also, the scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX) were used to determine the morphological changes and elemental analysis of the biosorbent before and after the sorption process. The Langmuir isotherm was in perfect agreement with the equilibrium empirical data of thorium biosorption and the highest sorption capacity of the Chlorella Vulgaris microalgae was determined as 185.19 mg g−1. Also, the results of kinetic studies show that the thorium biosorption process follows a pseudo-second-order kinetic model. The negative value of ΔG0 indicates spontaneity and the positive values of ΔH0 indicate the endothermic nature of the adsorption process. [ABSTRACT FROM AUTHOR]

MgO–ZrO 2 refractories were produced by combining MgO refractories (with a CaO/SiO 2 ratio of 2.1) with monoclinic ZrO 2 powder using wet-bag cold isostatic pressing. The phase composition and mechano-physical properties of the MgO–ZrO 2 materials were influenced by the interaction between ZrO 2 and MgO refractories. ZrO 2 enhanced the cold modulus of fracture of MgO refractories but decreased the hot modulus of fracture due to changes in bonding phases. The addition of 1 wt% ZrO 2 transformed Ca 2 SiO 4 into CaMgSiO 4 and CaZrO 3. CaMgSiO 4 with a low melting point deteriorated the hot modulus of fracture of MgO–ZrO 2 refractories from 13.3 to 2.97 MPa. With an increase in ZrO 2 to 3–5 wt.%, CaMgSiO 4 remained while CaZrO 3 gradually transformed into the solid-solution Ca 0.2 Zr 0.8 O 1.8. This transformation occurred because ZrO 2 seized CaO from CaZrO 3 to stabilize itself. Based on thermodynamic equilibrium ZrO 2 preferentially reacts with CaO-containing phases in the MgO matrix in the following order: Ca 3 SiO 5 > Ca 2 SiO 4 > CaZrO 3 > CaMgSiO 4. The thermal shock resistance of MgO–ZrO 2 refractories with less than 5 wt% ZrO 2 was not significantly improved by assessing their strength loss and coefficient of thermal expansion. In conclusion, it is recommended to incorporate ZrO 2 into MgO refractories with low SiO 2 or CaO to develop high-performance MgO–ZrO 2 refractories. [ABSTRACT FROM AUTHOR]

A thermodynamic analysis was performed for the production of synthesis gas and hydrogen gas from steam reforming of propionic acid, one of the constituents of the bio-oil, using ASPEN Plus v8.8. The aim of the study was to perform a global analysis on steam reforming of propionic acid focusing on several parameters such as steam-to-propionic acid ratio, reaction temperature, addition of O 2 in the feed stream and presence of CaO as a CO 2 sorbent in the reaction environment. The results showed that higher amounts of steam/propionic acid ratio resulted in higher H 2 and CO 2 yields. It was also observed that high H 2 O/PA molar ratios led to reduced coke production as WGS reaction was favored with excess steam, causing CO in the reaction mixture to be consumed through the WGS reaction rather than the Boudouard reaction. Addition of O 2 in the reaction environment was observed to negatively affect yield of H 2. Yet, coke formation was deprived and increasing the O 2 amount in the feed stream decreased the energy required for the process. Furthermore, the presence of CaO enhanced H 2 yield and energy requirements of the process compared to conventional steam reforming process. 100 % yield of H 2 production with a heat generation of −83.4 MJ/kmol of PA and almost zero formation of CO 2 , CO, CH 4 and coke is achieved at 600 °C for sorption enhanced steam reforming of propionic acid. [Display omitted] • Maximum H 2 production is noted as 4.96 kmol/kmol of PA at 750 °C for H 2 O/PA = 4. • O 2 /PA molar ratio significantly affect the heat requirement & coke deposition. • Process enthalpy changes from 38.5 to −49.5 & −83.4 MJ/kmol with higher CaO. • 100% H 2 yield is achieved for CaO = 3 kmol/h at 600 and 700 °C. [ABSTRACT FROM AUTHOR]

Energy sources all around the world are degrading at a rapid pace. The exponential rise in population, along with urbanization, requires exploration and advancement in diverse fuel resources. Municipal solid waste (MSW) disposal requires urgent intervention in terms of its utilization and conversion into useful energy forms than being dumped into landfills. Though efforts are being made for its combustion in furnaces, the plastic contents in RDF often pose environmental concerns when used for combustion. The gasification process has been explored for the effective processing of different forms of waste in the present study. The composition of MSW varies widely with demography, weather, and habitats. In the present study, MSW of Surat metropolitan city of India is processed post collection, through sorting, segregation, and compaction, and transformed to fuel, which is termed as refuse-derived fuel (RDF). A chemical representation of the RDF is used to perform gasification studies with the help of two thermodynamic equilibrium models. Parametric analysis of the gasification models is performed to analyze the effect of equivalence ratio and gasification reaction temperatures on the product gas composition for the prepared composition of RDF. Results reveal that the combined equilibrium model is more accurate in predicting product gas composition compared to the Homogeneous model. It is observed that the variation of the equivalence ratio has a more significant influence on the product gas composition than the variation in the gasification temperature. The study concludes that RDF from MSW may be efficiently transformed into useful gaseous fuel through gasification resulting in product gas with a calorific value of approximately 25 MJ per kg of RDF gasified. [ABSTRACT FROM AUTHOR]

Ion‐acoustic waves (IAWs) commonly occur near interplanetary (IP) shocks. These waves are important because of their potential role in the dissipation required for collisionless shocks to exist. We study IAW occurrence statistically at different heliocentric distances using Solar Orbiter to identify the processes responsible for IAW generation near IP shocks. We show that close to IP shocks the occurrence rate of IAW increases and peaks at the ramp. In the upstream region, the IAW activity is highly variable among different shocks and increases with decreasing distance from the Sun. We show that the observed currents near IP shocks are insufficient to reach the threshold for the current‐driven instability. We argue that two‐stream proton distributions and suprathermal electrons are likely sources of the waves. Plain Language Summary: Ion‐acoustic waves (IAWs) are fluctuations in the electric field that occur at frequencies close to the ion plasma frequency. These waves are commonly found in the solar wind and often cluster around interplanetary (IP) shock waves. In this study, we investigate and quantify how common IAWs are in the vicinity of IP shocks. Our research revealed that IAW activity is enhanced before and after most IP shock passages. Furthermore, IAWs are more likely to be observed preceding IP shocks that are closer to the Sun. We find that the occurrence rate of IAWs shows no clear dependence on the IP shock parameters. We explore the possible mechanisms that could explain the presence of these IAWs. For instance, IAW modes can be excited by electric currents if the associated drift velocity between ions and electrons is above a certain threshold. However, the currents alone are not strong enough to generate the IAWs found near IP shocks. We discuss other potential generation mechanisms, such as velocity distributions of ions and electrons deviating from thermodynamic equilibrium. Key Points: The occurrence of Ion‐acoustic waves (IAWs) is enhanced at interplanetary (IP) shocks, peaking at the shock rampThe occurrence rate of IAWs in the upstream region of IP shocks increases with decreasing radial distance from the SunIAWs are observed upstream of an IP shock together with two‐stream protons and an electron strahl [ABSTRACT FROM AUTHOR]

Understanding the explosion mechanism and hydrodynamic evolution of core-collapse supernovae (SNe) is a long-standing quest in astronomy. The asymmetries caused by the explosion are encoded into the line profiles which appear in the nebular phase of the SN evolution – with particularly clean imprints in He star explosions. Here, we carry out nine different supernova simulations of He-core progenitors, exploding them in 3D with parametrically varied neutrino luminosities using the prometheus-hotb code, hydrodynamically evolving the models to the homologous phase. We then compute nebular phase spectra with the 3D Non-Local Thermodynamic Equilibrium spectral synthesis code extrass (EXplosive TRAnsient Spectral Simulator). We study how line widths and shifts depend on progenitor mass, explosion energy, and viewing angle. We compare the predicted line profile properties against a large set of Type Ib observations, and discuss the degree to which current neutrino-driven explosions can match observationally inferred asymmetries. With self-consistent 3D modelling – circumventing the difficulties of representing |$^{56}$| Ni mixing and clumping accurately in 1D models – we find that neither low-mass He cores exploding with high energies nor high-mass cores exploding with low energies contribute to the Type Ib SN population. Models which have line profile widths in agreement with this population give sufficiently large centroid shifts for calcium emission lines. Calcium is more strongly affected by explosion asymmetries connected to the neutron star kicks than oxygen and magnesium. Lastly, we turn to the near-infrared spectra from our models to investigate the potential of using this regime to look for the presence of He in the nebular phase. [ABSTRACT FROM AUTHOR]

To explain the impact of geological and process factors on underground coal gasification in deep coal seam (>2200 m) and promote the efficient and clean extraction and conversion of coal, this study employs the orthogonal experimental design method to investigate the impact of CO 2 coefficient (0–1), moisture content (30–80 wt%), calcite content (0–10 wt%), albite content (0–10 wt%), kaolinite content (0–20 wt%), reaction temperature (550–650 °C), and reaction pressure (23–27 MPa) on the characteristics of coal underground gasification under supercritical H 2 O/CO 2 conditions. Furthermore, range analysis and variance analysis are utilized to determine the degree of influence of each factor and the interaction between factors. Finally, the Gibbs free energy minimization method is used to conduct a thermodynamic equilibrium analysis of coal supercritical H 2 O/CO 2 gasification at high temperatures (750–1000 °C). The results indicate that the three most significant factors affecting the process of coal supercritical H 2 O/CO 2 gasification are the CO 2 coefficient, moisture content, and reaction temperature. The maximum carbon gasification efficiency at 650 °C in experimental cases and 1000 °C in simulation cases is 22.2% and 88.1%, respectively. Although the addition of CO 2 at lower temperatures reduces the carbon gasification efficiency, at high temperatures (>900 °C), a higher initial CO 2 concentration increases the carbon gasification efficiency. The addition of CO 2 under conditions of low moisture content increases the mole fraction of H 2 , but reduces it under conditions of high moisture content (≥70 wt%). Among the three minerals, calcite has the most significant influence on the gasification process. • Analyzed the effects of different factors on underground coal gasification in deep coal seam. • The interaction of CO 2 coefficient with temperature and moisture content is analyzed. • The effect of calcite, albite and kaolinite is limited. • At ≥950 °C, CO 2 can increase the carbon gasification efficiency. • When the moisture content ≤60 wt%, CO 2 can increase the mole fraction of H 2. [ABSTRACT FROM AUTHOR]

Lewisite is a representative chemical warfare agent that contains arsenic. Thermal decomposition is an essential method for Lewisite destruction, and appropriate destruction conditions can enhance the environmental friendliness of this method by minimizing the hazards of destruction products. In this study, the variation of Lewisite during pyrolysis and incineration was calculated, with particular emphasis on the evolution behaviors of arsenic and chloride with temperature, pressure, and molar ratio. The main products identified during pyrolysis were HCl(g), C, As, and AsCl3(g). Under anoxic conditions, AsCl3(g) and As were the dominant species. In oxygen‐enriched conditions, arsenic existed primarily as AsCl3(g), As2O5, As2O4, and AsOCl. Below 600 °C, arsenic predominantly existed in high valence forms such as As2O5. Above 600 °C, the binding capacity of chlorine and arsenic was stronger than that of oxygen, resulting in an AsCl3(g) molar fraction exceeding 75 % at 1200 °C. The primary chlorides in oxygen‐enriched conditions were Cl2(g), HCl(g), AsCl3(g), and Cl(g). Lower incineration temperatures (around 500 °C), sufficient oxygen conditions (molar ratio above 4 : 1), and positive pressures were conducive to reducing the toxicity of destruction products. The results are in good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

I discuss how five reasonably sounding assumptions lead to a dilemma — the Page-time paradox — which appears to challenge a conventional statistical mechanical underpinning of black hole thermodynamics. By inspecting the conceptual subtleties behind each hypothesis, I list questions that require clarification before the puzzle can be deemed paradoxical. I devote particular attention to using thermodynamic arguments for a system that never reaches equilibrium. As a proof of concept, I show that the paradox is absent in a modified setting that admits an equilibrium thermodynamics formulation. [ABSTRACT FROM AUTHOR]

Biogas presents a renewable fuel source with substantial potential for reducing carbon emissions in the energy sector. Exploring this potential in the farming sector is crucial for fostering the development of small-scale distributed biogas facilities, leveraging indigenous resources while enhancing energy efficiency. The establishment of distributed biogas plants bolsters the proportion of renewable energy in the energy matrix, necessitating efficient power generation technologies. Given their proximity to bio-waste production sites like farms and digesters, optimising combined heat and power generation systems is imperative for energy self-sufficiency. Small-scale biogas facilities demand specific power generation technologies capable of achieving notable efficiencies, ranging from 40% to 55%. This study focuses on employing Solid Oxide Fuel Cells (SOFCs) in biogas-to-power systems and investigates the theoretical operation of SOFCs with fuel mixtures resulting from different biogas lean upgrading pathways. Therefore, starting from ten mixtures including CH4, CO2, H2, H2O, N2, and O2, the study proposes a method to assess their impact on the electrochemical performance, degradation, and energy equilibrium of SOFC units. The model embeds thermodynamic equilibrium, the Nernst potential, and energy balance, enabling a comprehensive comparison across these three analytical domains. The findings underscore the unsuitability of dry biogas and dry biomethane due to the potential risk of carbon deposition. Moreover, mixtures incorporating CO2, with or without H2, present significant thermal balance challenges. [ABSTRACT FROM AUTHOR]

The modes of occurrence, migration, and evolution pathways of lithium (Li) and gallium (Ga) during combustion of an Al-rich coal from Inner Mongolia, China, were investigated using methods of simulated combustion experiments, the sequential chemical extraction procedure (SCEP), and the thermodynamic equilibrium calculation. Mineralogical and chemical compositions of the feed coal and combustion ash were analyzed by X-ray fluorescence (XRF), X-ray diffraction (XRD), inductively coupled plasma mass spectrometry (ICP-MS), and scanning electron microscopy (SEM). The study reveals that Li and Ga are significantly enriched in the ash after combustion, with the contents reaching up to 1086 μg/g and 133 μg/g, respectively. The primary modes of occurrence of Li and Ga in the ash are quartz and aluminosilicates, and sulfides, respectively. Li, in the form of LiAlSi4O10 (s), primarily occurs in hematite, glass, and quartz below 800 °C. However, it migrates into the glass phase, mullite, and quartz above 1000 °C. On the other hand, Ga exists as Ga4S5 (s) and transforms into Ga2S (g) as the temperature rises from 800 °C to 1000 °C, maintaining this gaseous form until 1200 °C. Ga4S5 (s) predominantly occurs in the glass phase at 600 °C, whereas mullite and quartz become its dominant modes of occurrence in industrial combustion ashes and ashes obtained from simulated combustion above 600 °C. [ABSTRACT FROM AUTHOR]

Dimethyl ether (DME) has promising properties as e‐fuel and platform chemical. Its direct synthesis from CO2 and hydrogen, which is thermodynamically more favorable than the indirect route over methanol, is reviewed. Systematic thermodynamic equilibrium calculations are evaluated and compared to bifunctional catalysis experiments performed with Cu/ZnO/ZrO2 methanol catalyst and ferrierite or heteropolyacid‐coated dehydration catalysts under thermodynamic and kinetic conditions. In the thermodynamic region, the methyl yield of direct DME synthesis is superior over sole methanol synthesis. Significant differences among the solid acids used are absent. However, under kinetic conditions, the heteropolyacid‐coated catalysts show superior performance for dehydration over zeolites. [ABSTRACT FROM AUTHOR]

Nitrous oxide (N 2 O) emissions sourced from agricultural and industrial activities have gained much attention because of their contribution to the global greenhouse effect and ozone layer depletion. Significant efforts have been devoted to developing the cost-effective and highly efficient technologies for N 2 O removal. The direct N 2 O decomposition is limited by the thermodynamic equilibrium at high temperatures. Recently, catalytic reduction of N 2 O with carbon-free hydrogen derived from in situ ammonia decomposition is considered as an ideal approach. Herein, thermal decomposition of N 2 O is investigated by employing a BaCe 0.85 Fe 0.15 O 3-δ -BaCe 0.15 Fe 0.85 O 3-δ (BCF8515-BCF1585) hydrogen-transporting membrane or a Ce 0.85 Sm 0.15 O 1.925 -Sm 0.6 Sr 0.4 FeO 3-δ (SDC-SSF) oxygen-transporting membrane respectively. It is noted that the membrane catalysis of N 2 O decomposition by reacting with permeated hydrogen or via in-situ oxygen removal displayed significant advantages over the direct thermal decomposition of N 2 O under a fixed bed condition. Moreover, the N 2 O conversion as well as hydrogen/oxygen permeability of such membranes were greatly improved by the introduction of porous Ni–CeO 2 or SDC-NCO layers due to the increased catalytic activities and hydrogen/oxygen surface exchange kinetics. [ABSTRACT FROM AUTHOR]

We consider three different systems in a heat flow: an ideal gas, a van der Waals gas, and a binary mixture of ideal gases. We divide each system internally into two subsystems by a movable wall. We show that the direction of the motion of the wall, after release, under constant boundary conditions, is determined by the same inequality as in equilibrium thermodynamics d U − đ Q ≤ 0 . The only difference between the equilibrium and non-equilibrium laws is the dependence of the net heat change, đ Q , on the state parameters of the system. We show that the same inequality is valid when introducing the gravitational field in the case of both the ideal gas and the van der Waals gas in the heat flow. It remains true when we consider a thick wall permeable to gas particles and derive Archimedes' principle in the heat flow. Finally, we consider the Couette (shear) flow of the ideal gas. In this system, the direction of the motion of the internal wall follows from the inequality d E − đ Q − đ W s ≤ 0 , where d E is the infinitesimal change in total energy (internal plus kinetic) and đ W s is the infinitesimal work exchanged with the environment due to the shear force imposed on the flowing gas. Ultimately, we synthesize all these cases within a general framework of the second law of non-equilibrium thermodynamics. [ABSTRACT FROM AUTHOR]

Electrochemical oxidation of cyclohexane to KA oil, a mixture of cyclohexanone and cyclohexanol, holds great promise for decarbonized chemical manufacturing based on the value of products and the thermodynamic equilibrium potential. However, fundamental understanding of this reaction is extremely limited. For example, even the number of electrons in this reaction has not yet been identified. In this work, we elucidate the mechanism of electrochemical cyclohexane oxidation to KA oil on fluorine-doped tin oxide (FTO), platinum, and glassy carbon anodes. Using three-electrode electroanalysis, isotopic labeling, and concentration studies, we show that electrochemical cyclohexane oxidation to KA oil is similar to its thermochemical analogue in that O2, not water, is the primary oxygen source. The reaction is initiated through the formation of cyclohexyl or hydroxyl radicals, depending on electrode and electrolyte composition. Additionally, crossover from undivided two-electrode cells is found to impact measurements such that cathodic reaction and reactor design may introduce potential artifacts to anodic activity and selectivity. These findings have significant implications for the technological viability of a theoretically promising electrosynthesis process. [ABSTRACT FROM AUTHOR]

In this study, the thermodynamic simulation model and system of the copper side-blown smelting process were established using the chemical equilibrium constant method, based on the process reaction mechanism, multiphase equilibrium principle, and MetCal software platform (MetCal v7.81). Under typical production conditions, the composition of the product and the distribution behavior of impurity elements were simulated. The results indicate that the average relative error between the calculated mass fractions of major elements such as Cu, S, Fe, SiO2, CaO, MgO, and Al2O3 in copper matte and smelting slag, and the actual production values, is 4.25%. Additionally, the average relative error between the calculated distribution ratios of impurity elements such as Pb, Zn, As, Bi, Mo, Au, and Ag in copper matte and smelting slag, and the actual production data, is 6.74%. Therefore, this model and calculation system accurately reflects the actual production situation of the copper side-blown smelting process well and has potential to predict process output accurately while optimizing process parameters, effectively guiding production practice. [ABSTRACT FROM AUTHOR]

The underutilization of steelmaking slags is primarily ascribed to instability, predominantly influenced by their intricate phase structure. The presence of MgO, a key constituent in steelmaking slag, contributes to the challenges faced in steelmaking slag recycling and sustainable steel production practices. There are currently uncertainties surrounding the impact of fluctuations in MgO content on the mineral phase of steelmaking slag, as well as ongoing controversy regarding the influence of the RO phase on slag stability. This study investigates the phase evolution and microstructures of steelmaking slag with varying MgO contents during the cooling process through high-temperature experiments and FactSage thermodynamic equilibrium calculations. The principal phases in steelmaking slag, namely α′-Ca2SiO4 (C2S), RO (MgO–FeO solid solution), Ca2Fe2O5 (C2F) and Ca3SiO5 (C3S), were identified using XRD and SEM-EDS analyses. As the MgO content increases, the MgO content within the RO continued to increase. With a MgO content of 10 mass pct in steelmaking slag, the precipitation of C3S commences during the cooling of the steelmaking slag. The average size of C3S reaches up to 400 μm, markedly higher than the 35 μm size of C2S. This disparity is attributed to the higher nucleation rate of C2S compared to C3S, coupled with a lower growth rate. The augmentation of MgO content in steelmaking slag induces changes in the C3S formation, facilitated by the substitution of Ca2+ in C3S by Fe2+ and Mg2+.The significance of this work lies in unraveling the intricacies of steelmaking slag behavior, providing crucial insights for optimizing recycling processes. This research sheds light on the factors that influence the phase composition and stability of steelmaking slag, contributing to the utilization of steelmaking slags, promoting environmental sustainability, and bolstering the overall efficiency of metallurgical processes in the current industrial landscape. [ABSTRACT FROM AUTHOR]

Carbon monoxide (CO) emission has been observed in a number of core-collapse supernovae (SNe) and is known to be an important coolant at late times. We have implemented a chemical reaction network in the radiative-transfer code cmfgen to investigate the formation of CO and its impact on SN ejecta. We calculate two 1D SN models with and without CO: a BSG explosion model at one nebular epoch and a full time-sequence (50–300 d) for a red supergiant explosion. In both models, CO forms at nebular times in the dense, inner regions at velocities <2000 km s |$^{-1}$|  where line emission from CO can dominate the cooling and reduce the local temperature by as much as a factor of 2, weakening emission lines and causing the optical light curve to fade faster. That energy is instead emitted in CO bands, primarily the fundamental band at |$\sim 4.5 \mathrm{\mu m}$|⁠ , which accounts for up to 20 per cent of the total luminosity at late times. However, the non-monotonic nature of the CO cooling function can cause numerical difficulties and introduce multiple temperature solutions. This issue is compounded by the sensitivity of the CO abundance to a few reaction rates, many of which have large uncertainties or disparate values across literature sources. Our results also suggest that, in many SNe, CO-level populations are far from their local thermodynamic equilibrium values. Unfortunately, accurate collisional data, necessary to compute non-local thermodynamic equilibrium populations, are limited to a few transitions. [ABSTRACT FROM AUTHOR]

In recent times, there has been an amplified interest in exploring fresh applications of biogas, attributed to the rising concerns surrounding climate change and an enhanced emphasis on the utilization of renewable energy sources. This manuscript undertakes a comprehensive assessment of recent advancements in the domains of dry, bi-, and tri-reforming. Notably, it emphasizes situations in which the CO 2 present in biogas assumes the role of an oxidant or partial oxidant. A comparative evaluation of various techniques and the exploration of recent catalysts employed in the reforming process and techno-economic biogas conversion applications are also deliberated in this analysis. Biogas conversion exhibits economic feasibility, typically with a payback period ranging from 4 to 8 years. Opting for a higher reaction temperature within the range of 830–900 °C is typically favored as it results in increased CH 4 and CO 2 conversions within the bi-reforming of the biogas process. Similarly, the temperature range is maintained between 750 and 850 °C and 850–1000 °C or above (depending on various factors) for dry reforming and tri reforming respectively. In general, biogas can undergo conversion processes to produce hydrogen, methanol, compressed natural gas, liquid fuel, wax, and form of heat. The inclusive conversion of biogas efficiency ranges from around 35%–80%, depending on the specific type of product being generated. [Display omitted] • Study investigates biogas valorization for H 2 production. • Desire H 2 /CO molar ratio decreases for H 2 production above 2.2. • Ni/CeO 2 –ZrO 2 nanoparticles appear promising as a catalyst. • Bi, dry, and tri-reforming optimize at 830–900 °C, 750–850 °C, and 850–1000 °C or higher, respectively. • Biogas conversion is 35–80% efficient, with a 4–8 year average payback period based on economic analysis. [ABSTRACT FROM AUTHOR]

We synthesized 2‐(1‐1,2‐dicarbadodecaboranyl(12))‐6,6,12,12‐tetramethyl‐7,8,11,12‐tetrahydro‐6H,10H‐phenaleno[1,9‐fg]pyrido[3,2,1‐ij]quinoline (4), a julolidine‐like pyrenyl‐o‐carborane, with pyrene substituted at the 2,7‐positions on the HOMO/LUMO nodal plane. Using solid state molecular structures, photophysical data, cyclic voltammetry, DFT and LR‐TDDFT calculations, we compare o‐carborane and B(Mes)2 (Mes=2,4,6‐Me3C6H2) as acceptor groups. Whereas the π‐acceptor strength of B(Mes)2 is sufficient to drop the pyrene LUMO+1 below the LUMO, the carborane does not do this. We confirm the π‐donor strength of the julolidine‐like moiety, however, which raises the pyrene HOMO‐1 above the HOMO. In contrast to the analogous pyrene‐2‐yl‐o‐carborane, 2‐(1‐1,2‐dicarbadodecaboranyl(12))‐pyrene VI, which exhibits dual fluorescence, because the rate of internal conversion between locally‐excited (LE) and charge transfer (CT) (from the pyrene to the carborane) states is faster than the radiative decay rate, leading to a thermodynamic equilibrium between the 2 states, 4 shows only single fluorescence, as the CT state involving the carborane as the acceptor moiety in not kinetically accessible, so a more localized CT emission involving the julolidine‐like pyrene moiety is observed. [ABSTRACT FROM AUTHOR]

Context. Open clusters provide valuable information on stellar nucleosynthesis and the chemical evolution of the Galactic disk, as their age and distances can be measured more precisely with photometry than in the case of field stars. Aims. Our aim is to study the chemical distribution of the Galactic disk using open clusters by analyzing the existence of gradients with Galactocentric distance, azimuth, or height from the plane and dependency with age. Methods. We used the high-resolution spectra (R > 60 000) of 194 stars belonging to 36 open clusters to determine the atmospheric parameters and chemical abundances with two independent methods: equivalent widths and spectral synthesis. The sample was complemented with 63 clusters with high-resolution spectroscopy from literature. Results. We measured LTE abundances for 21 elements: α (Mg, Si, Ca, and Ti), odd-Z (Na and Al), Fe-peak (Fe, Sc, V, Cr, Mn, Co, Ni, Cu, and Zn), and neutron-capture (Sr, Y, Zr, Ba, Ce, and Nd). We also provide non-local thermodynamic equilibrium abundances for elements when corrections are available. We find inner disk young clusters enhanced in [Mg/Fe] and [Si/Fe] compared to other clusters of their age. For [Ba/Fe], we report an age trend flattening for older clusters (age < 2.5 Ga). The studied elements follow the expected radial gradients as a function of their nucleosynthesis groups, which are significantly steeper for the oldest systems. For the first time, we investigate the existence of an azimuthal gradient, finding some hints of its existence among the old clusters (age > Ga). [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) are a group of fluorinated synthetic chemicals that are highly recalcitrant, toxic, and bio-accumulative and have been detected in biosolids worldwide, posing potential risks to humans and the environment. Recent studies suggest that the organic C-F bond in PFAS can be destructed and potentially mineralised into inorganic fluorides during thermal treatment. This study focuses on thermodynamic equilibrium investigations and the fate of fluorine compounds post-PFAS destruction during biosolid thermal treatment. The results indicate that gas-phase fluorine compounds are mainly hydrogen fluoride (HF) and alkali fluorides, whereas solid-phase fluorine compounds include alkaline earth fluorides and their spinels. High moisture and oxygen content in the volatiles increased the concentration of HF in the gas phase. However, adding minerals reduced the emission of HF in the gas phase significantly and enhanced the capture of fluorine as CaF2 spinel in the solid phase. This study also investigates the effect of feedstock composition on the fate of fluorine. High ash content and low volatile matter in the feedstock reduced HF gas emissions and increased fluorine capture in the solid product. The findings of this work are useful in designing thermal systems with optimised operating conditions for minimising the release of fluorinated species during the thermal treatment of PFAS-containing biosolids. [ABSTRACT FROM AUTHOR]

As the understanding of natural gas hydrates as a vast potential resource deepens, their importance as a future clean energy source becomes increasingly evident. However, natural gas hydrates trend towards secondary generation during extraction and transportation, leading to safety issues such as pipeline blockages. Consequently, developing new and efficient natural gas hydrate inhibitors has become a focal point in hydrate research. Kinetic hydrate inhibitors (KHIs) offer an effective solution by disrupting the nucleation and growth processes of hydrates without altering their thermodynamic equilibrium conditions. This paper systematically reviews the latest research progress and development trends in KHIs for natural gas hydrates, covering their development history, classification, and inhibition mechanisms. It particularly focuses on the chemical properties, inhibition effects, and mechanisms of polymer inhibitors such as polyvinylpyrrolidone (PVP) and polyvinylcaprolactam (PVCap). Studies indicate that these polymer inhibitors provide an economical and efficient solution due to their low dosage and environmental friendliness. Additionally, this paper explores the environmental impact and biodegradability of these inhibitors, offering guidance for future research, including the development, optimization, and environmental assessment of new inhibitors. Through a comprehensive analysis of existing research, this work aims to provide a theoretical foundation and technical reference for the commercial development of natural gas hydrates, promoting their safe and efficient use as a clean energy resource. [ABSTRACT FROM AUTHOR]

The aim of the present work is to propose an alternative hydrogen production process using water and sustainable feedstocks to promote the utilisation of cheap and renewable raw materials on a large scale by increasing flexibility, efficiency, and eco-compatibility of existing technologies without sacrificing their reliability and affordability. The idea is to combine non-catalytic Partial Oxidation and Moderate or Intense Low-oxygen Dilution combustion technologies by adding water. Thermodynamic equilibrium calculations, accompanied by kinetic modelling, are used to assess and interpret the general behaviour of a potential unit that uses the interaction of these two technologies and to compare the performances over a range of operating conditions of interest. The results show that thermochemical production of H 2 using the proposed process is theoretically feasible and has the potential to offer many advantages over standard processes. The immediate advantage of such an approach is that a very high H 2 /CO ratio can be obtained that could eliminate the water gas shift conversion stages, making the reactor more compact and simple than conventional reformers. Moreover, water vapour addition limits the formation of soot precursors due to a "leaning" effect from releasing hydroxyl radicals. • An alternative hydrogen production process using sustainable feedstocks is proposed. • The process combines non-catalytic partial oxidation and MILD combustion with water. • The idea has the potential to offer many advantages over standard processes. [ABSTRACT FROM AUTHOR]

The HfO2–Ta2O5 system was investigated using two distinct methods: the equilibration method at temperatures ranging from 1 573 to 1 873 K and the differential thermal analysis method up to 2 473 K. To identify the phases, X‐ray diffraction (XRD) and scanning electron microscopy with energy‐dispersive X‐ray spectroscopy (SEM/EDX) were employed. The temperature of the eutectic reaction L→Hf6Ta2O17+Ta2O5 was measured to be 2 052 K and the eutectic composition to be 66.7 mol.% Ta2O5. The peritectic reaction L+HfO2→Hf6Ta2O17 was observed at a temperature of 2 287 K. The heat capacity of the Hf6Ta2O17 phase was measured using differential scanning calorimetry from 240 to 1 300K. The thermodynamic database for the HfO2–Ta2O5 system was derived. [ABSTRACT FROM AUTHOR]

We present a new routine for calculating the non-local thermodynamic equilibrium (non-LTE) 15 µ m CO 2 cooling–heating of mesosphere and lower thermosphere in general circulation models. It uses the optimized models of the non-LTE in CO 2 for day and night conditions and delivers cooling–heating with an error not exceeding 1 K d -1 even for strong temperature disturbances. The routine uses the accelerated lambda iteration and opacity distribution function techniques for the exact solution of the non-LTE problem and is about 1000 times faster than the standard matrix and line-by-line solution. It has an interface for feedbacks from the model and is ready for implementation. It may use any quenching rate coefficient of the CO 2 (ν2) + O(3 P) reaction, handles large variations in O(3 P), and allows the user to vary the number of vibrational levels and bands to find a balance between the calculation speed and accuracy. The suggested routine can handle the broad variation in CO 2 both below and above the current volume mixing ratio, up to 4000 ppmv. This allows the use of this routine for modeling Earth's ancient atmospheres and the climate changes caused by increasing CO 2. [ABSTRACT FROM AUTHOR]

In order to separate phenol from water, at 101.3 kPa, the liquid-liquid equilibria (LLE) data of water + phenol + solvents (trichloromethane, isoamyl alcohol) were obtained at 298.15, 303.15, and 313.15 K. The ability of the extractant to extract phenol from water was evaluated by the distribution coefficient (D) and selectivity coefficient (S). The Bachman and Hand equations were used to verify the reliability of the LLE data with the linear coefficient was greater than 0.98%. The LLE data was correlated with the NRTL and UNIQUAC models to obtain a binary interaction parameter with an RMSD not greater than 0.36%. [ABSTRACT FROM AUTHOR]

A novel method for preparing CuW composite containing micro- and nano-tungsten particles coated with SixWy phase via silicothermic coupling with aluminothermic reduction is presented in this paper. Compared with powder metallurgy, this method avoids the long sintering process at high temperatures and has the advantages of short process flow and low energy consumption. The thermodynamic equilibrium of the Al-Si-CuO-WO3 system was calculated, and CuW and slag samples were systematically analyzed. The results show that it is feasible to prepare a composite containing micro- and nano-tungsten particles coated with SixWy phase via silicothermic coupling with aluminothermic reduction, and the microstructure of CuW composites mainly composed of matrix, spherical tungsten particles wrapped with irregular SixWy phase and a small number of black inclusions. With an increase in RSi, the proportion of black inclusions decreased, tungsten-containing phases increased and the size distribution range and average diameter of tungsten-containing phases in slag showed an increasing trend. [ABSTRACT FROM AUTHOR]

The solubility of nicotinohydrazide in two binary solvents were determined by a static weight method from 293.15 to 318.15 K. It found that the solubility of nicotinohydrazide was influenced by temperature, solvent polarity, and solvent composition. Meanwhile, the TG-DSC analysis was used to obtain the weight change and thermal effect of nicotinohydrazide. The XRD analysis indicated that the crystal morphology of nicotinohydrazide was coincident in five different solvents. Furthermore, the models including modified Apelblat equation, Van't Hoff equation, Jouyban-Acree model, and CNIBS/R-K model were used to fit the experimental data. It was concluded that the four models were reliable in fitting the experimental data. Then the dissolution apparent thermodynamic was obtained, which explained well the dissolution of nicotinohydrazide. This study could help optimize and control the industrial crystallization of nicotinohydrazide. [ABSTRACT FROM AUTHOR]

Glycylglycine (Gly–Gly) is a crucial biochemical reagent widely used in cosmetics, food additives, and medicine. Using the equilibrium method, the solubility data of Gly–Gly in four binary solvents (ethanol/isopropanol/ethanediol/acetone + water) were investigated at temperatures over a range of 288.15–328.15 K under 101.3 kPa, as well as in the binary solvent of acetic acid + water from 293.15 to 333.15 K. The solubility data were correlated by Apelblat-Jouyban Acree, Van't Hoff-Jouyban Acree, and CNIBS/Redlich-Kister models. Additionally, the radial distribution function was obtained through molecular dynamic simulation. It presented the unusual dissolution behavior of Gly–Gly in acetic acid and water mixture. The apparent thermodynamic properties, including standard enthalpy, Gibbs free energy, and entropy change of dissolution, were obtained accordingly. This article could help the industrial crystallization of Gly–Gly. [ABSTRACT FROM AUTHOR]

A new series of 20-component fluorite-based compositionally complex oxides (20CCFBO x Nb/Ta) with the general chemical formula (15RE 1/15) 2 x +1 (Ce 1/3 Zr 1/3 Hf 1/3) 3–3 x (Nb 1/2 Ta 1/2) x O 8- δ (0 ≤ x ≤ 1, where 15RE 1/15 = La 1/15 Pr 1/15 Nd 1/15 Sm 1/15 Eu 1/15 Gd 1/15 Tb 1/15 Dy 1/15 Y 1/15 Ho 1/15 Er 1/15 Tm 1/15 Yb 1/15 Lu 1/15 Sc 1/15) are synthesized. Despite that the Gibbs phase rule allows for the existence of up to 20 phases at the thermodynamic equilibrium, 17 of the 20CCFBO x Nb/Ta compositions synthesized in this study all possess single ultrahigh-entropy phases in fluorite, pyrochlore, or weberite structure, as shown by X-ray diffraction (XRD). Only < 1 vol% of secondary phases are observed in two compositions near the phase-transition points. With changing compositional variable x , this series of 20CCFBO x Nb/Ta undergoes an abrupt fluorite-pyrochlore transition at x = ∼0.27 and an abrupt pyrochlore-weberite transition at x = ∼0.87. Careful characterization reveals abrupt changes of order parameters at both phase transitions. In addition, weberite short-range ordering can persist into the long-range pyrochlore phase, which leads to the lowest thermal conductivities. [ABSTRACT FROM AUTHOR]

Interface termination bonding between metal oxide and metals is discussed from the viewpoint of thermodynamics. The method of interface termination prediction proposed by the authors for Al2O3–metal and ZnO–metal interfaces is extended to a general interface between metal-oxide and metals. The extension of the prediction method to the interface between metal oxides and elemental semiconductors is also discussed. Information on interface bonding was extracted by carefully examining the experimental results and first-principles calculations in the references. The extracted information on interface bonding from references is compared with the results obtained via the proposed prediction method. It is demonstrated that interface termination bonding can be predicted by extending the method to oxide–metal interfaces in general, when there is no interface reaction such as the reduction of oxide, oxidation of metal, or mixed oxide formation. The method uses only basic quantities of pure elements and the formation enthalpy of oxides. Therefore, it can be applied to most of the metals (including elemental semiconductors) in the periodic table and metal oxides with one stable valence. The method is implemented as a software, “InterChemBond”, and can be used free of charge.

Abstract To improve the utilization of byproduct gases in the steel plant, the coke oven gas (COG) methanation combined with blast furnace gas (BFG) and basic oxygen furnace gas (BOFG) was proposed in viewpoint of economy and environment. The optimization mathematics model based on Gibbs free energy minimization was established to predict the thermodynamic feasibility of the proposed methanation. To solve the proposed model, the convenient method was implemented by using the Gibbs module in Aspen Plus software. Effects of operation parameters on the methanation performance were revealed to identify the optimized conditions. To reduce the solid carbon concentration, it was found that the optimized conditions of temperature, pressure and stoichiometric number were 650 °C, 30 bar and 3.0, respectively. Moreover, it was discovered that 10 mol% of BFG or BOFG could be mixed into COG to obtain the maximum methane yield. In addition, it was testified that there were the good agreements between calculated results and industrial and published data, which indicated that the proposed methanation was thermodynamically feasible. Therefore, the simple and easy method was developed to evaluate the methanation operating conditions from the aspect of thermodynamic equilibrium, which provided the basic process conditions of byproduct gases methanation to enhance the steel plant efficiency and reduce carbon emissions.