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Natural gas hydrates, mainly existing in permafrost and on the seabed, are expected to be a new energy source with great potential. The exploitation technology of natural gas hydrates is one of the main focuses of hydrate-related studies. In this study, a large-size liquid aqueous solution wrapping a methane hydrate system was established and molecular dynamics simulations were used to investigate the phase equilibrium conditions of methane hydrate at different methane concentrations and interfacial geometries. It is found that the methane concentration of a solution significantly affects the phase equilibrium of methane hydrates. Different methane concentrations at the same temperature and pressure can lead to hydrate formation or decomposition. At the same temperature and pressure, in a system reaching equilibrium, the size of spherical hydrate clusters is coupled to the solution concentration, which is proportional to the Laplace pressure at the solid–liquid interface. Lower solution concentrations reduce the phase equilibrium temperature of methane hydrates at the same pressure; as the concentration increases, the phase equilibrium temperature gradually approaches the actual phase equilibrium temperature. In addition, the interfacial geometry of hydrates affects the thermodynamic stability of hydrates. The spherical hydrate particles have the highest stability for the same volume. Through this study, we provide a stronger foundation to understand the principles driving hydrate formation/dissociation relevant to the exploitation of methane hydrates. [ABSTRACT FROM AUTHOR]

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

Sulfate-type salt lakes constitute over half of the total salt lakes in China and are rich in rare elements, such as rubidium and cesium. However, the complex interactions between ions make the separation and extraction process quite challenging. To address this, phase equilibrium studies were conducted on the sulfate system containing rubidium, cesium, and magnesium. Specifically, the phase equilibria of the aqueous quaternary system Rb+, Cs+, Mg2+//SO42− - H2O at 323.2 K were investigated using the isothermal dissolution method. The solubility, density, and refractive index of the system were experimentally measured. The results indicate that the system at 323.2 K belongs to a complex type with the formation of one solid solution (Rb, Cs)2SO4 and two double salts (Rb2SO4·MgSO4·6H2O, Cs2SO4·MgSO4·6H2O). The corresponding phase diagram consists of four quaternary invariant points, nine univariate curves, and six crystallization regions. Among these, the crystalline region for Cs2SO4·MgSO4·6H2O is the largest, while that for the single salt Cs2SO4 is the smallest. Moreover, the crystalline regions for the double salt and solid solutions are significantly larger than those for the single salt, highlighting the difficulty in separation of valuable single salts. A comparison of multi-temperature phase diagrams from 298.2 K to 323.2 K reveals that the crystalline form of MgSO4 changes from MgSO4·7H2O (298.2 K) to MgSO4·6H2O (323.2 K). As the temperature increases, the phase regions for Rb2SO4, Cs2SO4, (Rb, Cs)2SO4, and Cs2SO4·MgSO4·6H2O expand, while the phase region of Rb2SO4·MgSO4·6H2O contracts, indicating that the single salts (Rb2SO4, Cs2SO4) are more readily precipitated at higher temperature, which provides theoretical guidance for the future production and separation of Rb, Cs, and Mg from sulfate-type salt lakes. [ABSTRACT FROM AUTHOR]

Alchemical free energy calculations via molecular dynamics have been applied to obtain thermodynamic properties related to solid–liquid equilibrium conditions, such as melting points. In recent years, the pseudo-supercritical path (PSCP) method has proved to be an important approach to melting point prediction due to its flexibility and applicability. In the present work, we propose improvements to the PSCP alchemical cycle to make it more compact and efficient through a concerted evaluation of different potential energies. The multistate Bennett acceptance ratio (MBAR) estimator was applied at all stages of the new cycle to provide greater accuracy and uniformity, which is essential concerning uncertainty calculations. In particular, for the multistate expansion stage from solid to liquid, we employed the MBAR estimator with a reduced energy function that allows affine transformations of coordinates. Free energy and mean derivative profiles were calculated at different cycle stages for argon, triazole, propenal, and the ionic liquid 1-ethyl-3-methyl-imidazolium hexafluorophosphate. Comparisons showed a better performance of the proposed method than the original PSCP cycle for systems with higher complexity, especially the ionic liquid. A detailed study of the expansion stage revealed that remapping the centers of mass of the molecules or ions is preferable to remapping the coordinates of each atom, yielding better overlap between adjacent states and improving the accuracy of the methodology. [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]

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

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

Binary terpenoid-based eutectic systems consisting of the natural substances camphene (CA), fenchol (FE), thymol (TH), menthol (ME), dodecanoic acid (DA), and 1-dodecanol (DO) are synthesized and screened for their Solid–Liquid Equilibrium (SLE) and eutectic compositions. Out of nine eutectic systems, 13 solvent compositions at eutectic points and next to them, in addition to the reference solvent, TH:ME, are synthesized and applied for the solvent extraction of the aromatic aldehydes vanillin (VAN), syringaldehyde (SYR), and p-hydroxybenzaldehyde (HYD) from an acidic aqueous model solution. The extraction efficiency is determined from aldehyde concentrations measured by High-Performance Liquid Chromatography (HPLC), taking into consideration mutual solubility measured by Karl Fischer titration (KF) and a Total Organic Carbon-analysis (TOC). Physicochemical properties, such as the density, viscosity, and stability of the solvents, are evaluated and discussed. Additionally, 1H-NMR measurements are performed to verify hydrogen bonding present in some of the solvents. The results show that all synthesized eutectic systems have a strong hydrophobic character with a maximum water saturation of ≤2.21 vol.% and solvent losses of ≤0.12 vol.% per extraction step. The hydrophobic eutectic solvents based on CA exhibit lower viscosities, lower mutual solubility, and lower extraction efficiency for the aromatic aldehydes when compared with FE-based solvents. The highest extraction efficiencies for VAN (>95%) and for SYR (>93%) at an extraction efficiency of 92.61% for HYD are achieved by the reference solvent TH:ME (50:50 mol.%). With an extraction efficiency of 93.08%, HYD is most preferably extracted by the FE–DO-solvent (80:20 mol.%), where the extraction efficiencies for VAN and SYR reach their maximum at 93.37% and 90.75%, respectively. The drawbacks of the high viscosities of 34.741 mPas of the TH:ME solvent and 31.801 mPas of the FE–DO solvent can be overcome by the CA–TH solvent, which has a viscosity of 3.436 mPas, while exhibiting extraction efficiencies of 71.92% for HYD, >95% for VAN, and >93% for SYR, respectively. [ABSTRACT FROM AUTHOR]

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

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

Textile dyes are frequently disposable in aqueous effluents, making it difficult to remove them from industrial effluents before their release to natural waters. This paper deals with the fabrication of cellulose-based adsorbents by reacting nanocelulose crystalline (nanocel) with N-[3-(trimethoxysilyl)propyl]ethylenediamine (TMSPEDA), forming the hybrid (silylpropyl)ethylenediamine@nanocellulose (SPEDA@nanocel), which was employed as adsorbent for the uptake of reactive yellow 2 dye (RY-2) from aqueous effluents. Characterisation of SPEDA@nanocel was carried out using FTIR, SEM–EDS, XRD, TGA, surface area, pHpzc, and hydrophobicity/hydrophilicity ratio (HI). Also, adsorption studies were thoroughly investigated. The effect of initial pH indicated that the maximum uptake of RY-2 takes place at pH 2, which is an indication of the electrostatic mechanism. The kinetic data carried out with 250 and 500 mg L−1 RY-2 with SPEDA@nanocel followed better the nonlinear fractional-like pseudo-first-order model. The t0.5 and t0.95 for the dye uptake were about 30 and 141 min, respectively. The equilibrium data from 10 to 45 °C indicated that the Liu isotherm model was the best-fitted isothermal model. The maximum sorption capacity attained was 112.3 mg g−1 at 45 °C. The thermodynamic data have shown that the equilibrium was favorable and endothermic, and the ΔH° was compatible with an electrostatic attraction between RY-2 and SPEDA@nanocel. Experiments of desorption of loaded adsorbent showed promising results for real applications since at least 5 adsorption/desorption cycles could be employed without significant changes in the recovery and with high precision. [ABSTRACT FROM AUTHOR]

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

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

We report the accurate determination of solid–liquid equilibria using a novel molecular simulation method that can be used for solid–liquid equilibria from low to high pressures. A re-evaluation is reported of the solid–liquid equilibria of the noble gases interacting via ab initio two-body potentials combined with three-body interactions and quantum corrections and the results are compared with both existing simulation data and experimental values. The new simulation method yields results that are generally in closer agreement with the experiment than exiting methods, highlighting the important role of the method in fully understanding the interatomic interactions responsible for solid–liquid equilibria. The quality of the comparison of simulation results with the experiment indicates that the solid–liquid equilibria of the noble gases can be now predicted with exceptional accuracy over a large range of pressures. [ABSTRACT FROM AUTHOR]

Reducing the contact time between droplets and solid surfaces is important in anti-icing surface design. The present work investigates the impact dynamics of nanodroplets on hydrophobic/superhydrophobic surfaces decorated by point textures via molecular dynamics (MD) simulations, aiming to significantly reduce the contact by the point textures. Based on distinguishing outcome regimes into a phase diagram, the point texture is found to not affect the outcome regimes of sticky, bouncing, and splash, whereas the internal rupture regime is significantly enhanced so that the new outcome in this regime, ring-bouncing, which is reported for the first time at the nanoscale, is also significantly reinforced. Impacting nanodroplets with ring-bouncing behaviors have remarkably reduced the contact time due to the saved retraction time via creating a retraction of both inner and outer contact lines. Subsequently, an energy conservation equation from the initial to the bouncing states is established for identifying the boundary of this outcome regime, which shows good agreement with the outcome phase diagram. Finally, impacting nanodroplets with three diameters of 8, 10, and 14 nm are implemented for understanding how the ratio of the droplet size to the texture point affects the reduction of the contact time. The MD results show the cases of 8-nm nanodroplets displaying the best performance of reducing the contact time by 52%, which is superior to current studies in reducing the contact time at the nanoscale. This can be explained by the lower ratio of droplet diameter to texture size leading to a further shorter distance of retraction after the internal rupture and hence a shorter contact time. [ABSTRACT FROM AUTHOR]

The phase relationships of Eu 2 O 3 - Gd 2 O 3 – ZrO 2 system at 1873 K and 1673 K were investigated. To experimentally determine the phase relationships, the scanning electron microscopy, X-ray diffraction, and electron probe microanalyzer with wavelength dispersive spectrometer were employed. Our findings indicated that there were no ternary compounds. However, the binary pyrochlore phases (Eu 2 Zr 2 O 7 and Gd 2 Zr 2 O 7) formed a continuous solid solution, denotated as (Eu 2-x Gd x)Zr 2 O 7 at 1673 K. Moreover, the solubility of Gd 2 O 3 was observed to reach at least 28.0 mol.% along Eu 2 Zr 2 O 7 - Gd 2 O 3 composition line at 1873 K. Additionally, a continuous cubic solid solution was formed between C–Gd 2 O 3 and C–Eu 2 O 3 at 1673 K. The obtained experimental data were utilized to optimize the thermodynamic parameters for the Eu 2 O 3 - Gd 2 O 3 – ZrO 2 system. Thermodynamic modeling was carried out to reproduce the present phase diagram experimental results and isothermal phase diagrams of this ternary system at 1673 and 1873 K were calculated. [ABSTRACT FROM AUTHOR]

AbstractThe synthesis of composites comprising chitosan (CS) and magnetite using the co-precipitation method yielded a compound denoted as CS/Fe3O4, which demonstrated magnetic properties. FTIR analysis confirmed the presence of magnetite nanoparticles within the composite. This CS/Fe3O4 composite proved to be highly efficient in adsorbing tetracycline (TC) from solutions of tetracycline hydrochloride (HTCCl), achieving an adsorption efficiency exceeding 65%. Moreover, the composite maintained its adsorption capacity over five cycles of sorption-desorption, indicating its robustness and reusability. The Langmuir isotherm provided a suitable description of the liquid-solid equilibrium of TC at 25 °C and 35 °C. Thermodynamic analysis revealed interesting insights into the nature of TC adsorption on CS. At low concentrations, the adsorption process was found to be exothermic, while at very high concentrations, it became endothermic. This observation suggests that the adsorption of TC at low concentrations is governed by protonation of chitosan and, at high concentrations, by entropic factors, highlighting the importance of considering thermodynamic parameters in understanding the adsorption mechanism. Overall, these findings contribute to the development of efficient and cost-effective adsorbents for the removal of TC from aqueous solutions. [ABSTRACT FROM AUTHOR]

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

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

This study focuses on the improvement of bioremediation of textile dye Reactive Red 195 using agro-industrial waste, groundnut oil cake (GNOC) obtained after oil-pressing. The treatment of GNOC with 1 N H2SO4 had resulted in physiochemical changes on the insoluble porous adsorbent, which improved their adsorption efficiency. The dye removal efficiency increased from 55% to 94% on acidification of GNOC. The raw groundnut oil cake (RGNOC) and acid-treated groundnut oil cake (AGNOC) were characterized using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction, and zeta potential. The rate and efficiency of dye adsorption were examined using adsorption kinetics and isotherm models. The results confirm that acid-treated GNOC eliminates impurities, alter the surface functional groups, and significantly increase porous surface areas of RGNOC. The investigation of key factors such as contact time, initial concentration of dye, static/agitation impact, particle size, and adsorbent dose had significantly influenced adsorption capacity of GNOC. Adsorption of dye fits best into the Langmuir model and equilibrium data of dye on AGNOC was explained by psuedo-second-order reaction with maximum adsorption capacity of 12.65 mg/g. This emphasis AGNOC has a very excellent potential to remove the textile dye Reactive Red dye from industrial effluent. This study reports the primary investigation exploring the application of groundnut oil cake (RGNOC) and its acid-modified (AGNOC) version for the bioremediation of industrially used textile dye Reactive Red 195 (RR195). The core objective of this study is to use a low-cost biosorbent to remove RR195 dye from effluent that pose risk to the health and environment. This study analyses the adsorption capacity of RGNOC and its acid-modified version AGNOC to treat contaminated water and the influencing parameters. AGNOC adsorption potential for RR195 dye sequestration was shown to be higher compared to RGNOC. Acidification of the adsorbent is simple, cost expensive, and more efficient alternate approaches to scale up for industrial application. As a result, an attempt has been made to add a new adsorbent to the database. [ABSTRACT FROM AUTHOR]

Acer truncatum seed oil, extracted from the samaras of the yuanbaofeng (A. truncatum Bunge) tree, is rich in oleic acid, palmitic acid (PA), erucic acid (EA), and nervonic acid (NA). The melt crystallization is a crucial way to isolate NA. In this present study, the solid–liquid equilibrium of erucic acid/palmitic acid (EA– +PA), erucic acid/nervonic acid (EA–NA), and nervonic acid/palmitic acid (NA–PA) binary systems was investigated by differential scanning calorimetry. The solid–liquid phase diagrams of binary systems were constructed by thermodynamic analysis and model simulations, which illustrated the influence of molecular interaction on the melting point change of binary systems. The solid–liquid phase and the enthalpy change diagrams together demonstrated eutectic phenomenon. The eutectic behavior appeared in the EA–NA and EA–PA binary systems at the EA concentration more than 50% and 70%, respectively. Additionally, the FTIR spectra of PA, EA, NA, and various binary systems were characterized, which found that there was no chemical interaction between the binary components. Based on the calculation of the enthalpy, onset melting temperature, and peak temperature in the melting stage, the melting Gibbs free energy of binary systems during phase transformation was predicted. These findings provided a fresh light for the separation of NA from A. truncatum seed oil, hence providing theoretical instruction for the separation of fatty acids in plant oil. [ABSTRACT FROM AUTHOR]

A new thermodynamic assessment of the Co–Ti system is presented on the basis of the literature data concerning phase equilibria and thermodynamics. A set of parameters of Gibbs-energy expressions for phases is obtained by means of CALPHAD approach. Excess Gibbs energy of fcc, bcc, and hcp disordered solutions is modeled using Redlich-Kister polynomials. The thermodynamic properties of liquid alloys are described using the associate solution model. Compound Energy Formalism is used to describe the thermodynamic properties of Laves C15 and C36 phases and order-disorder transformations L12-A1 and B2-A2 by applying of the corresponding two-sublattice models. The CoTi2 compound is treated as stoichiometric. The phase diagram, coordinates of invariant equilibria, and thermodynamic properties of liquid and solid phases are calculated. Metastable phase transformations with the participation of supercooled liquid alloys and boundary solid solutions are analyzed. [ABSTRACT FROM AUTHOR]

Knowledge of the rates of dissolution of rock-forming minerals close to equilibrium and their dependence on Δ G r , the Gibbs free energy of reaction, is essential for describing the temporal and spatial evolution of many environmental and engineering processes involving solid/fluid interactions. In the present study we used the isotope-doping method to quantify albite forward and net dissolution rates. Batch experiments were performed at 150, 180 °C and pH = 9 at near equilibrium and equilibrium conditions (-25 ≤ Δ G r ≤ + 8.2 kJ/mol) in 29Si spiked solutions which were undersaturated with the secondary Al-Si solid phases likely to precipitate. The forward dissolution rates normalized to the initial BET surface area were found to decrease continuously and monotonically with increasing time and Δ G r , achieving values 1.3 to 2.4 orders of magnitude lower at chemical equilibrium than initial far from equilibrium values, with the highest rate decrease for the highest solid to fluid ratio. These rate drops were accompanied by an increase in BET specific surface areas associated with the formation of widespread dissolution features. A decrease of albite forward dissolution rate together with an increase of its BET surface area was also observed as a function of reaction time at far from equilibrium conditions (Δ G r ≤ − 65 kJ/mol). These observations are consistent with a continuous decrease with time and increasing Δ G r of albite effective surface area linked to the formation of unreactive negative crystal facets, in addition to etch pits stopping nucleating above a critical value of Δ G r. Thus, the observed decrease in albite dissolution rate as equilibrium is approached is not linked primarily to the increase in the contribution of the backward reaction but rather to the decrease of the forward reaction rate in conjunction with the decrease in the density of reactive sites at the mineral surface. The results of this study show that the characterization of the effective surface area and its evolution with reaction time and chemical affinity is crucial to deriving robust dissolution rates of well-crystallized minerals like feldspars. Dissolution experiments in 29Si spiked solutions of samples with different history and well-characterized effective surface area and surface morphology should help to better quantify the rate laws controlling silicate minerals weathering. [ABSTRACT FROM AUTHOR]

This study explores the adsorption of doxycycline (DOX) from aqueous solutions onto biochar derived from banana peel, which was prepared using a potassium hydroxide activation method (KOH-BPB). The biochar properties were characterized based on morphology, surface area (SBET of 710.241 m² g-1), functional groups, and surface charge (pHPZC = 7.7). Parameters, including initial pH, DOX concentration, and ionic strength, that influenced the DOX adsorption capacity of KOH-BPB were examined. Adsorption equilibrium of DOX on KOH-BPB was assessed through four isothermal models: the Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich models. The obtained data were most compatible with the Langmuir model (R² = 0.9879). KOH-BPB has a maximum DOX absorption capacity of 121.95 mg g-1 which exceeds that of many comparable absorbents. The maximum DOX removal was 96.7% at pH 6, a DOX concentration of 20 mg L-1, and a KOH-BPB dose of 1.0 g L-1. These findings reveal that biochar from banana peel effectively removes antibiotic residues from water. This study provides a potential, low-cost, and environmentally friendly adsorbent. [ABSTRACT FROM AUTHOR]

What is the most favorite and original chemistry developed in your research group? We originally proposed the design principle for molecular ferroelectrics: ferroelectrochemistry, including quasi‐spherical theory, the introduction of homochirality, and H/F substitution. Ferroelectrochemistry changed the blind search for molecular ferroelectrics into targeted chemical design, which will develop into a new discipline. How do you get into this specific field? Could you please share some experiences with our readers? I have been devoted to the field of molecular ferroelectrics for more than 20 years. In the early stage, I worked on non‐centrosymmetric metal‐organic complexes, which are potential molecular ferroelectrics. This laid a foundation for my further study of molecular ferroelectrics. Non‐centrosymmetric crystal symmetry is only one of the necessary requirements for ferroelectrics, which must adopt one of the 10 polar crystallographic point groups and should also generally undergo symmetry‐breaking phase transitions. Due to the lack of a feasible method, the discovery of molecular ferroelectrics has long depended on blindly searching. This process is like finding a needle in a haystack. After years of exploration in this field, I fully understood the Landau phase transition phenomenological theory, Curie symmetry, and Neumann principle from a chemical perspective, and proposed the design principle for molecular ferroelectrics: ferroelectrochemistry, transforming the discovery of molecular ferroelectrics from blind search to targeted chemical design. Never give up no matter how much difficulty you have met, because maybe there is an opportunity the next second. What is the most important personality for scientific research? Curiosity, divergent thinking, perseverance, team spirit, and gratitude. How do you supervise your students? Emphasis on independent problem‐solving abilities. Encourage students to read professional books frequently while doing research. What are your hobbies? What's your favorite book(s)? Jogging, reading, and swimming. My favorite book is The Journey to the West. Comprehensive Summary: Molecular ferroelectrics have attracted tremendous attention in the past decades due to their excellent ferroelectric performance and superiorities of easy processability, mechanical flexibility, and good biocompatibility. However, the discovery of molecular ferroelectrics is a great challenge and has long relied on blind search. This situation changed recently, with the development of ferroelectrochemistry proposed by our group. As a major design approach in ferroelectrochemistry, introducing homochirality, which facilitates the crystallization of materials in polar crystallographic point groups, greatly improves the probability of being ferroelectrics. Various new molecular ferroelectrics with splendid properties have been precisely synthesized by using this efficient and universal strategy. In this review, we summarize the advances in the chemical design of molecular ferroelectrics through the strategy of introducing homochirality. Key Scientists: [ABSTRACT FROM AUTHOR]

Phase equilibria in the CaO–SiO2–CrOx system were experimentally investigated at 1600°C and pO2 of 10−10 to 10−11 atm using the high‐temperature isothermal equilibration/drop quenching/electron probe X‐ray microanalysis technique. The constrained isothermal sections of the CaO–SiO2–CrOx system were constructed at 1600°C and pO2 of 10−10 to 10−11 atm based on the experimental results. The primary phase fields including cristobalite (SiO2), larnite (Ca2SiO4), (Ca,Cr)Cr2O4, and corundum (Cr2O3) were determined. Simulations by thermodynamic software MTDATA, FactSage, and Thermo‐Calc were compared with the present experimental results. [ABSTRACT FROM AUTHOR]

The solubility of two natural phenolic compounds (vanillic acid (VA) and vanillin (V)) in four individual solvents (ethanol, butan-2-ol, ethylene glycol, and ethyl acetate) was measured using the gravimetric method from 283.15 to 323.15 K at atmospheric pressure. The optimization of the complexes between VA--solvents and V--solvents using the B3LYP theoretic technique and the 6-31+G (d, p) basis set indicated that the absolute value of interaction energy was higher, suggesting that the interaction between solute and the solvent was stronger. In addition, two excellent activity coefficient models (NRTL and Wilson) were used to correlate and evaluate the equilibrium solubility results. The highest relative average deviation and root-mean-square deviation values for VA are 4.36% and 3.09 x 10-3, respectively, and 3.35% and 5.52 x 10-3 for V. Furthermore, the excess enthalpy of the solution was determined on the basis of thermodynamic relations and the Wilson model. The findings indicate that the dissolution process was endothermic. [ABSTRACT FROM AUTHOR]

The sulfur–iodine (S–I) thermochemical cycle for hydrogen production can be widely applied. The solubility of I 2 in complex and non-ideal HI–H 2 O–I 2 (HI x) ternary systems is critical for the phase separation behaviour and Bunsen reactor design. A new apparatus was established to measure the I 2 solubility using potentiometric titration. Fifty-two experimental data points of the I 2 solubility in the HI–H 2 O system were obtained at temperatures ranging from 293 K to 353 K, and the molar fraction of HI ranged from 7.69% to 15.74%. A new solubility model of I 2 in the HI–H 2 O system was developed using the solid-liquid phase equilibrium theory and a local composition model suitable for electrolyte systems (ELECNRTL). The complex effect of I 2 and I− promoting the dissolution of I 2 in the HI x system was also verified, in which the short-range interaction was dominant over the long-range interaction. The parameters of the model were determined by using the experimental data obtained in this work, where the average relative deviation (ARD) of the model was 2.73%. The model was also simultaneously validated using available experimental data, with which the calculated results were in agreement. This model satisfies the application requirements of the engineering design. • A high precision I 2 solubility measurement system for HI x solution system is established. • The I 2 solubility in HI x system is measured in the range of T = 293–353 K and x HI = 7.69–15.74%. • A high accuracy solubility model is established. • The change of internal forces in the HI x system is analysed. [ABSTRACT FROM AUTHOR]

This study investigates the phase equilibria of the Al-Mo-Hf ternary system at 400 °C and 600 °C using X-ray diffraction (XRD) and electron probe microanalysis (EPMA/WDS) techniques. Seven three-phase and five two-phase regions were identified at 400 °C, while eight three-phase and four two-phase regions were identified at 600 °C. Despite variations in the solid solubility ranges of certain compounds, the distribution of phase zones in the isothermal cross-section remained consistent at both temperatures. Using the experimental results and logical deductions, isothermal cross-sections were constructed for the Al-Mo-Hf ternary system at 600 °C and 400 °C. [ABSTRACT FROM AUTHOR]

Using Carex tristachya as the research object, the spectral characteristics of dissolved organic matter (DOM) in moss were analyzed using infrared spectroscopy, ultraviolet absorption spectroscopy, and three-dimensional fluorescence spectroscopy. The effect of DOM of Carex tristachya on soil adsorption of Cu2+ was studied through isothermal adsorption equilibrium experiments and adsorption kinetics experiments, and the changes in composition before and after the reaction between DOM of Carex tristachya and Cu2+ were analyzed. Research showed that the DOM of Carex tristachya had functional groups such as hydroxyl, carboxyl, carbonyl, and methyl, and was composed of four components: fulvic acid, fulvic acid like, humic acid like, and tryptophan like, with humic acid with relatively high molecular weight being the main component. Added DOM of Carex tristachya could reduce the maximum adsorption capacity, adsorption equilibrium rate, and adsorption affinity of Cu2+ in the soil. The ultraviolet region like fulvic acid and humic acid like substances in the DOM of Carex tristachya could form a complex with Cu2+ through functional groups such as carboxyl and hydroxyl groups. After the reaction, the number of unsaturated conjugated double bond structures, humification level, and the content of carbonyl, carboxyl, hydroxyl, and ester in the substituents on the aromatic ring of DOM of Carex tristachya significantly decreased. The research results provide basic data for the composition and structure of DOM of Carex tristachya, and provide scientific basis for resolving disputes over the impact of DOM on heavy metal activity. [ABSTRACT FROM AUTHOR]

Wettability of rock surfaces with respect to oil and water, which is characterized by the contact angle, is an important factor that determines the efficacy of enhanced oil recovery operations. Experimental determination of contact angles for oil–water–rock systems is expensive and time-consuming due to the extremely long times needed for the establishment of adsorption equilibrium at the liquid–solid interface. Hence, molecular simulations form an attractive tool for computing contact angles. In this work, we use the cleaving wall technique that was developed previously in our group [R. K. R. Addula and S. N. Punnathanam, J. Chem. Phys. 153, 154504 (2020)] to compute solid–liquid interfacial free energy, which is then combined with Young's equation to compute the oil–water contact angle on silica surfaces. The silica surface is modeled with the INTERFACE force field that has been developed to accurately reproduce experimental data. We have considered three different surface chemistries of silica, namely, Q2, Q3, and Q4, in this study. Our calculations reveal that while the Q2 and Q3 surfaces are completely wetted by water, the Q4 surface is partially non-wetted by water. All the simulations needed for this calculation can be performed using the Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) molecular package. This should facilitate wider adoption of the Young's equation route to compute contact angles for systems comprised of complex molecules. [ABSTRACT FROM AUTHOR]

The SiO2–H2O binary system serves as a basis for understanding complex silicate-water systems. In this study, based on limited existing experimental data of solubility, we propose a new thermodynamic model for SiO2–H2O fluid by modifying the traditional non-random two-liquid model with a simplified polymerization reaction. This model is applicable from 773 K to the anhydrous quartz melting temperature and from 0.5 GPa to at least 2 GPa across the critical conditions. It can predict solid–liquid equilibrium and vapor–liquid equilibrium in good agreement with available experiments. The upper critical endpoint of the SiO2–H2O system is predicted to be at ~ 1.14 ± 0.18 GPa and 1344 ± 87 K. With the new model, we obtain a quantitative three-dimensional pressure–temperature–composition phase diagram of the SiO2–H2O fluid, which greatly facilitates the understanding of the complex phase behavior of this binary around the upper critical endpoint. In addition, since the model is based on the Gibbs free energy foundation, we further discuss the derived density variations of SiO2–H2O fluid along with its complex phase changes in typical geochemical processes. [ABSTRACT FROM AUTHOR]

L‐Menthol is a commonly used material in food production for flavor enhancement and fragrances, as well as in pharmaceuticals. However, during the solution crystallization process of L‐menthol, there is a major issue of oiling out or liquid–liquid phase separation (LLPS) in most organic solvents and their mixtures. The objective of the current work is to prevent the LLPS phenomenon and grow high‐quality single crystals of L‐menthol. A water–ethanol mixed solvent with nine different mixing ratios is used, ranging from 0.99W:0.01E to 0.91W:0.09E, through the conventional slow evaporation process. The findings indicate that the mixing composition of the solvent plays a significant role in the variation of solubility, refractive index, LLPS, nucleation, and crystallization. This is clearly demonstrated in the phase diagram. The occurrence of LLPS phenomenon, nucleation, growth behavior, and morphology of L‐menthol single crystals through optical microscopy is identified. Additionally, the internal structure and thermal stability of the grown polymorphs using PXRD, SCXRD, and DSC analyses are confirmed. [ABSTRACT FROM AUTHOR]

With the (re)advent of eutectic mixtures within the field of deep eutectic solvents, special attention has been given to the measurement of solid–liquid equilibrium (SLE) phase diagrams, supported by the relevant information they can provide on the molecular interactions and melting temperature depression of any given system. As such, this work investigates the SLE phase diagrams of mixtures between ionic liquids and tetraalkylammonium chlorides (methyl, ethyl, and propyl), with the goal of decreasing the melting temperature of ionic liquids and ammonium salts, thus, expanding their application scope. Results show that tetraalkylammonium salts exhibit negative deviations from thermodynamic ideality when mixed with ionic liquids, which are increased by increasing their alkyl chain length and are interpreted in terms of anion exchange mechanisms. In turn, this nonideality contributes greatly to depression of the melting point of the ionic liquids examined. Overall, this work demonstrates that the correct combination of tetraalkylammonium/ILs anions and cations can lead to significant melting point depressions in both species, thus creating new ionic liquid mixtures using an approach akin to that used to form deep eutectic solvents. [ABSTRACT FROM AUTHOR]

To develop a better process for synthesizing sodium percarbonate and getting separation of the sodium salt, the equilibrium of the ternary system Na2SO4–H2O2–H2O and Na2CO3–H2O2–H2O at 5 °C was determined using the isothermal method, and the appropriate synthesis conditions for sodium carbonate from a theoretical perspective was discussed. The Na2SO4–H2O2–H2O system phase diagram contains one co-saturated point of Na2SO4·0.5H2O2·H2O and Na2SO4·10H2O. The Na2CO3–H2O2–H2O system phase diagram contains three crystal zones: Na2CO3·10H2O crystallization field, 0Na2CO3·1.5H2O2·H2O crystallization field and Na2CO3·2H2O2·H2O crystallization field. According to the phase diagram, the suitable raw material ratio of sodium percarbonate synthesis was obtained, to get the maximum of product yield, the optimal mass ratio of Na2CO3 to 30% H2O2 is 0.609. [ABSTRACT FROM AUTHOR]

Assessing the formation of a deep eutectic solvent (DES) necessitates a solid-liquid equilibrium phase diagram. Yet, many studies focusing on DES applications do not include this diagram because of challenges in measurement, leading to misidentified eutectic points. The present study provides a practical approach for estimating the phase diagram of any binary mixture from the structural information, utilizing machine learning and quantum chemical techniques. The selected machine learning model provides reasonably high accuracy in predicting melting point (R2 = 0.84; RMSE = 40.53 K) and fusion enthalpy (R2 = 0.84; RMSE = 4.96 kJ mol−1) of pure compounds upon evaluation by test data. By pinpointing the eutectic point coordinates within an extensive chemical space, we highlighted the impact of the mole fractions and melting properties on the eutectic temperatures. Molecular dynamics simulations of selected mixtures at the eutectic points emphasized the pivotal role of hydrogen bonds in dictating mixture behavior. Deep eutectic solvents are promising, sustainable alternatives for diverse applications, including separation, gas capture, electrodeposition, or nanomaterial synthesis, but our fundamental understanding of the nature of these solvents remains limited. Here, the authors report a practical approach for estimating the solid–liquid equilibrium phase diagram of any binary mixture from structural information, using machine learning and quantum chemical techniques. [ABSTRACT FROM AUTHOR]

Imiquimod (IMQ) has been successfully formulated to date mainly as semi-solid lipophilic formulations for topical application. In this study, we investigated the solubility of IMQ in solvents suitable for developing innovative formulations in the form of powder obtained, for instance, by spray drying; thus, water, ethanol, methanol, acetone, acetonitrile, and dimethyl sulfoxide were tested at different temperatures. Temperature variations, stirring intensity, and the contact time between IMQ and the solvent greatly affected the evaluation of IMQ equilibrium solubility. The attainment of the solid–liquid equilibrium requires 13 days starting from solid IMQ and 2 days from a cooled-down supersaturated IMQ solution. A correlation between IMQ solubility and the solubility parameters of solvents was not found. IMQ solutions in water, ethanol, methanol, acetonitrile, and dimethyl sulfoxide were neither ideal nor regular. The Scatchard–Hildebrand equation does not apply to IMQ solutions because of association phenomena due to intermolecular hydrogen bonds and/or π-stacking, as supported by the hyperchromic effect that was very pronounced in highly polar solvents, such as water, with the increase in temperature. Finally, IMQ solubility values measured in acetone cannot be considered reliable due to the reaction with the solvent, leading to the formation of new molecules. [ABSTRACT FROM AUTHOR]

The thermal characterization of two binary systems of n-alkanes that can be used as Phase Change Materials (PCMs) for thermal energy storage at low temperatures is reported in this work. The construction of the solid–liquid binary phase diagrams was achieved using differential scanning calorimetry (DSC) and Raman spectroscopy. The solidus and liquidus equilibrium temperatures were determined using DSC for thirty-nine different samples, three for the pure n-alkanes and the remaining for binary mixtures at selected molar compositions and used to acquire the corresponding solid–liquid phase diagrams. The two binary systems of n-octane/n-decane (C8/C10) and n-decane/n-dodecane (C10/C12) are characterized by a eutectic behavior at low temperatures. The eutectic temperature for the system C8/C10 was found at 211.95 K and the eutectic composition appeared at the molar fraction xoctane = 0.87. For the system C10/C12, the eutectic temperature was found at 237.85 K, and the eutectic composition appeared for the molar fraction xdecane = 0.78. This work aims to fulfill the lack of available data in the existing literature, considering the potential application of these systems for low-temperature thermal energy storage. Raman spectroscopy was used to complement the DSC data for the construction of the solid–liquid phase equilibrium diagrams, enabling the identification of the solid and liquid phases of the system. Additionally, the liquidus curve of the phase diagram was successfully described using a modified freezing point depression curve as fitting equation, the absolute root mean square deviation for the data correlation of the C8/C10 and C10/C12 systems being 2.56 K and 1.22 K, respectively. Ultimately, the fitting procedure also enabled a good prediction of the eutectic point for both studied systems. [ABSTRACT FROM AUTHOR]

In the equilibrium model of the solid surface–adatom system, including a three-dimensional interfacial surface, changes in surface properties are considered, taking into account the chemical potential due to the action of surface tension. The relationship between chemical potential and electrochemical potential of the th component in an electrochemical cell is analyzed. Using the density functional theory (DFT), the adsorption, electronic, and thermodynamic properties of 2 × 2 × 1 and 3 × 3 × 1 supercells of crystalline compounds ( , where and are stoichiometric coefficients) of the boundary binary systems of the ternary phase diagram of are studied. The stability of phases and property calculations are carried out with the exchange-correlation functional within the framework of the generalized gradient approximation (GGA PBE). The parameters of the crystal structures of the compounds , the adsorption energy of the lithium adatom on a substrate, the electronic structure, and the thermodynamic properties of supercells are calculated. The thermodynamically stable configurations of the supercells having different locations are determined. The DFT GGA PBE calculations of the enthalpy of formation of compounds are carried out in the ternary system. Taking into account the changes in the Gibbs free energy in the solid-phase exchange reactions between binary compounds, equilibrium sections (connodes) in the concentration triangle of the phase diagram are established. An isothermal section of the phase diagram at 298 K is constructed. The patterns of diffusion processes that are related to the movement of particles on the surface layer of the sample are analyzed. The activation energy of lithium diffusion in is calculated from the Arrhenius type relation in two temperature ranges (769–973 K) and (1873–2673 K). [ABSTRACT FROM AUTHOR]

The underground brines in the Sichuan Basin of China are rich in lithium, potassium, strontium, chlorine, etc. In order to fully develop and utilize these brine resources, it is necessary to carry out phase equilibrium research about the quaternary system LiCl–KCl–SrCl2–H2O and develop a reasonable lithium extraction process. The quaternary system LiCl–KCl–SrCl2–H2O at 273.2 K were determined using the isothermal dissolution equilibrium method. As a result, the corresponding phase diagrams were drawn based on the data. The phase diagram shows that the quaternary system LiCl–KCl–SrCl2–H2O has no double salt or solid solution at 273.2 K and there are two invariant points, five univariate curves and four solid phase crystallization fields, which are LiCl·2H2O, SrCl2·2H2O, SrCl2·6H2O and KCl. Furthermore, Pitzer's model was used to predict the solubility of salts in the quaternary system. The calculated values are in good agreement with the experimental ones. Finally, combined with isothermal evaporation method and the phase diagram of the quaternary system, a brine evaporation process was designed. [ABSTRACT FROM AUTHOR]

The solid-liquid equilibrium data of allantoin were determined by gravimetric method in four binary solvents (methanol-water, ethanol-water, ethylene glycol-water and methanolethylene glycol) at temperatures ranging from 288.15 to 333.15 K. The allantoin exhibited high solubility in ethylene glycol-water solvents. The solubility increased and then decreased with the increasing ratio of ethanol to water above 318.15 K. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) indicated that allantoin would be decomposed above 505 K (T5%). X-ray diffraction (XRD) showed that no crystalline transformation occurred in the investigated system. In the meanwhile, the experimental data were correlated by four thermodynamic models including modified Apelblat equation, Van't Hoff equation, Jouyban-Acree model, and kh equation. All the models fitted well with the experimental data. This study can help the industrial crystallization of allantoin. [ABSTRACT FROM AUTHOR]

It has been a challenge to distinguish between seismic anomalies caused by complex lithology and hydrocarbon reservoirs using conventional fluid identification techniques, leading to difficulties in accurately predicting hydrocarbon-bearing properties and determining oil-water contacts in reservoirs. In this study, we built a petrophysical model tailored to the deep-water area of the Baiyun Sag in the eastern South China Sea based on seismic data and explored the feasibility of the tri-parameter direct inversion method in the fluid identification of complex lithology reservoirs, offering a more precise alternative to conventional techniques. Our research found that the fluid modulus can successfully eliminate seismic amplitude anomalies caused by lithological variations. Furthermore, the seismic databased direct inversion for fluid modulus can remove the cumulative errors caused by indirect inversion and the influence of porosity. We discovered that traditional methods using seismic amplitude anomalies were ineffective in detecting fluids, determining gas-water contacts, or delineating high-quality reservoirs. However, the fluid factor Kf, derived from solid-liquid decoupling, proved to be sensitive to the identification of hydrocarbon-bearing properties, distinguishing between high-quality and poor-quality gas zones. Our findings confirm the value of the fluid modulus in fluid identification and demonstrate that the tri-parameter direct inversion method can significantly enhance hydrocarbon exploration in deep-water areas, reducing associated risks. [ABSTRACT FROM AUTHOR]

The solid-liquid equilibrium and thermodynamic properties of FOX-7 in three binary mixed solvents (N-methyl pyrrolidone-water, N,N-dimethylacetamide-water and 1,4-Butyrolactone-water) are studied by focused beam reflectance measurement (FBRM) dynamic detection method and the solubility is predicted by conductor-like screening model for real solvents (COSMO-RS) under atmospheric pressure from 298.15 to 343.15 K. The results show that the solubility of FOX-7 increase with the increasing temperature and the mole fraction of W-methyl pyrrolidone, N,N-dimethylacetamide and 1,4-Butyrolactone. The solubility data can be well correlated by Apelblat, van't Hoff and Yaws equation. The data of hybrid thermodynamic parameters (including the hybrid enthalpy, entropy, and Gibbs energy) show that the dissolution process is endothermic, non-spontaneous and enthalpy driven. In addition, COSMO-RS can accurately predict the increasing trend of solubility with increasing of temperature and mole fraction of solvent. However, the COSMO-RS overestimates solubility in three binary solvents except for xNMP = 0.1575, the average mean squared quadratic error becomes larger with an increasing mole fraction of water. Solubility data and thermodynamic parameters can lay a foundation for the crystallization and spheroidization modification of FOX-7. [ABSTRACT FROM AUTHOR]

A differential scanning calorimetric technique has been used to obtain solid–liquid equilibrium temperatures for the mixtures naphthalene or biphenyl + 1-tetradecanol, or + 1-hexadecanol. All the systems show a simple eutectic point, whose final composition was determined by means of the Tamman's plots using the needed values of the eutectic heat and of the heat of melting, which are also reported. DISQUAC interaction parameters for the OH/aromatic contacts in the selected systems are given. The present experimental SLE phase diagrams are similarly described by DISQUAC and UNIFAC (Dortmund) models. However, the comparison of DISQUAC and UNIFAC results for systems involving naphthalene and shorter 1-alkanols (methanol + 1-octanol) reveals that the temperature dependence of the interaction parameters is more suitable in DISQUAC. The systems are also investigated in terms of the concentration-concentration structure factor. It is shown that the positive deviations from the Raoult's law of the studied solutions become weaker when the homocoordination decreases. [ABSTRACT FROM AUTHOR]

With the advancement of oilfield extraction technology, since oil-water emulsions in waxy crude oil are prone to be deposited on the pipe wall, increasing the difficulty of crude oil extraction. In this paper, the mesoscopic dissipative particle dynamics method is used to study the mechanism of the crystallization and deposition adsorbed on the wall. The results show that in the absence of water molecules, the paraffin molecules near the substrate are deposited on the metallic surface with a horizontal morphology, while the paraffin molecules close to the fluid side are arranged in a vertical column morphology. In the emulsified system, more water molecules will be absorbed on the metallic substrate than paraffin molecules, which obstructed the direct interaction between paraffin molecules and solid surface. Therefore, the addition of water molecules hinders the crystallization of wax near the substrate. Perversely, on the fluid side, water molecules promote the formation of paraffin crystallization. The research in this paper reveals the crystallization mechanism of paraffin wax in oil-water emulsions in the pipeline from the microscopic scale, which provides theoretical support for improving the recovery of wax-containing crude oil and enhancing the transport efficiency. [ABSTRACT FROM AUTHOR]

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