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Cellulose nanocrystals (CNCs) have the potential to be used as functional hybrid composite materials derived from biological sources. CNCs possess a rod-like structure and surface functionality that allows for chemical modifications. These chemically modified CNCs exhibit liquid-crystalline phases, although their phase behavior has received less attention in research. For this study, we examined CNCs derived from waste lignocellulosic mass. We subjected them to chemical modification using maleic anhydride (MA) at a degree of substitution of 0.39 molecules of MA per glucose unit. The surface modification was confirmed using spectroscopic techniques. The diameter of CNCs that underwent MA tuning was decreased from the original size of 23.8–15.4 nm. The phase behavior of the modified MACNCs was thoroughly examined and showed a biphasic pattern until reaching a concentration of 9.65 × 107 nm−3. Furthermore, an assessment was conducted on the thermal stability of the prepared MACNCs, and a modeling approach was used to determine the thermal degradation kinetics. These MACNCs were used as a subtle pigment on paper through screen printing, stamping, and pen techniques. This type of aqueous ink is highly valuable for protecting books, drafts, and banknotes from counterfeiting. [ABSTRACT FROM AUTHOR]

Summary: Understanding the phase behaviour of biopolymer composites is vital for various technological applications, such as developing functional foods, nutraceuticals, encapsulation, isolation and fractionation of enzymes and proteins. The growing consumer demand for healthier food products pressures the food and nutraceutical industries to innovate while maintaining traditional texture and nutritional quality. This review critically examines various analytical techniques, including spectroscopic, microscopic, calorimetric, rheological, viscometry, and diffraction methods, used to study phase behaviour. Each technique provides unique insights into phase behaviour mechanisms at micro and macroscopic levels, with respective advantages and limitations discussed. The review advocates for a multi‐technique approach for a comprehensive understanding of phase behaviour and highlights the development of in situ probing techniques with minimal sample pre‐processing as a promising advancement. These innovations are expected to significantly enhance the practical applications of these techniques in the food industry, meeting current consumer demands without compromising traditional qualities. [ABSTRACT FROM AUTHOR]

Abstract Background Endogenous substances of krill oil (KO) are lipophilic in nature and have clinical significance viz. DHA/EPA, phospholipids and astaxanthin. To improve the nanodispersibility of endogenous substances of KO, a self-nanoemulsifying system (SNE) was developed. Results Ternary phase behaviour of KO was explored in ethanol (ET); propylene glycol, (PG); and PEG600 using Tween80 and Tween20 as surfactants. PEG600 induced the self-nanoemulsification of KO and yielded one phase region (OPR); dilution lines (KO/Smix fraction containing PEG600) traversed across OPR, produced a fully dilutable nanoemulsion system. PEG600-based nanoformulations (NFs) of KO underwent phase transformation via percolation behaviour in nanostructure domains (86–207 nm). PEG600 induced ternary phase behaviour of KO as revealed from rheological data (higher eta values), refractive index (nonlinear) and conductivity (bimodal) patterns. Induced phase transformation could be an interaction between aqueous phase and KO/Tween20 in PEG600 environment; generating highly viscous domains of low electrical conductivity. NFs offered antioxidant activity over corresponding coarse systems (p

Background: Endogenous substances of krill oil (KO) are lipophilic in nature and have clinical significance viz. DHA/EPA, phospholipids and astaxanthin. To improve the nanodispersibility of endogenous substances of KO, a self-nanoemulsifying system (SNE) was developed. Results: Ternary phase behaviour of KO was explored in ethanol (ET); propylene glycol, (PG); and PEG600 using Tween80 and Tween20 as surfactants. PEG600 induced the self-nanoemulsification of KO and yielded one phase region (OPR); dilution lines (KO/Smix fraction containing PEG600) traversed across OPR, produced a fully dilutable nanoemulsion system. PEG600-based nanoformulations (NFs) of KO underwent phase transformation via percolation behaviour in nanostructure domains (86–207 nm). PEG600 induced ternary phase behaviour of KO as revealed from rheological data (higher eta values), refractive index (nonlinear) and conductivity (bimodal) patterns. Induced phase transformation could be an interaction between aqueous phase and KO/Tween20 in PEG600 environment; generating highly viscous domains of low electrical conductivity. NFs offered antioxidant activity over corresponding coarse systems (p < 0.01) as measured using DPPH method. Optimized NFs (F4 and F6) inhibited the growth of skin cancer cell line (A431) in the range of 100–500 × dilutions. Conclusion: Phase behaviour of KO was induced by PEG600, transforming the dilution pattern via generation of one phase region; however, ethanol and propylene glycol as co-solvents did not. PEG600-based NFs of KO possessed antioxidant as well as cytotoxic to skin cancer cell lines (A431). [ABSTRACT FROM AUTHOR]

The surface activity of potassium heptylene decyl succinate (PHDS) at water-air interface was studied. The obtained results showed a very good correlation between the surface activity of PHDS and concentration of surfactant solutions and temperature of the system. The phase behaviour and structure of aggregates in PHDS)/water binary system were investigated. The phase diagram of the PHDS/water binary system was obtained depending on the concentration of components and temperature of the system. It was established that due to the double hydrocarbon chain of the PHDS molecule, the lamellar liquid crystalline phase exists across a wide range of the phase diagram. It was shown that upon the addition of water, the cross-sectional area of the PHDS molecules in lamellar liquid crystals is changed insignificantly. This result was associated with the invariability of the distance of the lipophilic layers of formed lamellar liquid crystals by PHDS molecules. On the basis of video-enhanced microscopic studies, it was established that in two-phase region of the phase diagram, lamellar liquid crystals coexist with water in the form of vesicles. [ABSTRACT FROM AUTHOR]

The hybrid steam-solvent injection has been considered as a promising technique for enhancing heavy oil/bitumen recovery， while its main mechanisms including the heat transferred and dissolution of solvents （e.g.， CH4， C2H6， C3H8， C4H10， CO2， N2， and DME） into heavy oil/bitumen to reduce its viscosity and swell it are closely related to the phase behaviour of the solvents/water/heavy oil systems. To allow the seamless integration with the existing reservoir simulators， the traditional cubic equations of state （i.e.， SRK EOS and PR EOS） have been modified and improved to accurately quantify the phase behaviour and physical properties of the aforementioned systems under equilibrium and nonequilibrium conditions. Firstly， a huge database has been built to develop the corresponding alpha functions by minimizing the deviation between the measured and calculated vapour pressures for water as well as non-hydrocarbon and hydrocarbon compounds available from the public domain. Such obtained alpha functions are further validated with enthalpy of vaporization for pure substances， and then the reduced temperature has been optimized and the eccentric factor has been redefined. Finally， a pressure-implicit strategy has been developed to optimize the binary interaction parameters （BIPs） by treating heavy oil as one pseudocomponent （PC） or multiple PCs. Also， the contributions of each solvent to the aforementioned systems have been compared and analyzed within a consistent and unified framework. In addition to new alpha functions for hydrocarbons and water， respectively， the reduced temperature is found to have its optimum value of 0.59 for the two equations of state （EOSs）， while 0.60 is recommended for practical use. Such improved EOSs have been further employed to reproduce the experimentally measured multiphase boundaries （or pseudo-bubble-point pressures）， density， viscosity， （mutual） solubility， and preferential mass transfer for the aforementioned mixtures under equilibrium and nonequilibrium conditions. The swelling effect for the heavy oil can be enhanced due to the addition of C3H8 and/or C4H10 or their mixtures into the CO2 stream. Due to the existence of water， isenthalpic flash leads to more accurate quantification of multiphase boundaries and physical properties for the hybrid solvent-thermal processes. Each component of a binary or ternary gas mixture is found to diffuse preferentially into heavy oil at high pressures and elevated temperatures in the absence and presence of porous media， while each of them is found to exsolve differently from gas-saturated heavy oil under nonequilibrium conditions.

The present work investigated the effects of some non‐condensable impurities (i.e., N2, O2, CH4, and Ar) on the phase behaviour of CO2‐rich systems at low temperature conditions (228.15–273.15 K). The study focused on bubble point measurements of CO2‐rich systems using the isothermal (pressure–volume) method at different mole fractions of CO2 (99.5%–95%). The obtained experimental data were used to validate multi‐fluid Helmholtz energy approximation (MFHEA) and Peng–Robinson (PR) equations of state (EoSs). For all data points, the measurements' uncertainties for temperature and pressure were 0.14 K and 0.03 MPa, respectively. While the composition uncertainty of the CO2 systems was a maximum of 0.024%. The findings reveal that as the mole fractions of the impurities increased, the bubble point pressures of the binary mixtures were elevated. Among all the investigated impurities, N2 has the most significant effect on the bubble point pressures of CO2 binary mixture at all the isotherms and compositions. Both MFHEA and PR models agreed well with the measured equilibrium points. For all systems, the average absolute deviations of the measured experimental data against the MFHEA and PR EoSs, were found to be less than 3.4% and 2.2%, respectively. Although the MFHEA EoS overpredicted most of the data points, the overall trend agreed with the experimental data and was consistent with the data available in the literature. The findings imply that the presence of these non‐condensable impurities (even as low as 0.5% mole fraction) increases the risk of two‐phase flow at higher pressures in a CO2‐rich system. © 2023 The Authors. Greenhouse Gases: Science and Technology published by Society of Chemical Industry and John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Past studies broadly discussed the effect of sulfur on the rheological properties of styrene–butadiene–styrene (SBS) modified asphalt, while the relationships between the rheological properties and phase behaviour of SBS-modified asphalt after sulfur vulcanisation have received less attention, which limits the further understanding of the relations between the structure and performance. To this end, this paper is aimed to discuss viscoelastic response at the molecular level and reveal the enhancement mechanism of SBS-modified asphalt after adding sulfur. Thus, the morphology, phase structure, and rheological behaviour of SBS/Sulfur modified asphalt were investigated by experimental assessment and molecular dynamics. Based on the results, it was found that the polybutadiene segments in SBS copolymer are the leading reactive site of vulcanisation, the interactions between SBS copolymer and light components were enhanced by sulfur treatment, the orderliness of asphalt molecules in SBS/sulfur modified asphalt was strengthened, and SBS copolymer presents a stronger attraction to aromatic after vulcanisation, which means the increase of boundary layer is also the significant cause to the improvement of compatibility. The findings are expected to deepen understanding of the vulcanisation mechanism and the rheological behaviour of SBS/Sulfur modified asphalt. [ABSTRACT FROM AUTHOR]

Asphalt pavements are continuously subjected to cyclic temperature variations induced by varying day–night and seasonal temperatures. However, the effect of thermal cycling on asphalt materials has not been thoroughly documented. This study conducted accelerated thermal cycling tests on asphalt mastics to simulate the environmental temperature variation. The evolution of the rheological properties and phase behaviors under cyclic temperature variations was clarified. The temperature factors sensitive to damage were identified by establishing the quantitative relationship between the cyclic temperature parameters and these properties. Results demonstrated that, as the expansion of cyclic temperature ranges, the three asphalt mastics gradually lost their viscosity properties and became increasingly elastic. Thermal cycling increased the stiffness and high temperature deformation resistance of the three asphalt mastics, but significantly reduced their stress relaxation capability. The phase structures were degraded upon thermal cycling, weakening the asphalt-aggregate interaction. The temperature difference and cyclic high temperature were the primary factors affecting the rheological performance of the asphalt mastics. SBS modified asphalt mastic displayed remarkable resistance to thermal cycling, demonstrating its potential for application in regions with frequent temperature fluctuations. This research can help us understand the evolution of asphalt pavement performance in areas with frequent temperature changes at a macro-level. [ABSTRACT FROM AUTHOR]

Cardanol is a natural material that acts to stabilize asphaltenes in crude oil. However, its derivative, polycardanol, obtained via cationic polymerization, has divergent behaviour, with reports of its acting both as asphaltenes stabilizer and flocculant. Recently, it was demonstrated that the reaction conditions influence the conversion rates, structures, and molar masses of the products from synthesizing polycardanol initiated with BF3 · O(C2H5)2. Seeking to elucidate the influence of these variables on the phase behaviour of asphaltenes, in this work six products, previously synthesized and characterized, had their performance evaluated by asphaltenes precipitation onset, using n‐heptane titration and monitoring by near‐infrared spectroscopy, using asphaltenes model systems (C5I and C7I) at 1.00 wt./vol.% in toluene. All the products had the ability to flocculate asphaltenes and have potential for deasphalting process. Flocculation efficiency increased with rising molar mass, higher reaction conversion degree, and presence of lateral hydrocarbon chains. The most efficient structures were not affected by the presence of unreacted cardanol. This indicated that the reaction does not require a purification step. Aged cardanol was also able to produce flocculant polymer, indicating that the distillation of cardanol is not required. The cost to obtain a product without needing reagent distillation becomes lower. [ABSTRACT FROM AUTHOR]

The article analyzes the modern theory and practice of transportation and storage of compressed natural gas. The expediency of the inclusion of a floating storage berth for the loading of gas carriers and container ships into the infrastructure of marine transportation of compressed natural gas is considered. Requirements for storage berth are formulated. It is shown that without using a marine mooring storage facility, the loading time of a gas carrier will considerably increase, and the economic efficiency of compressed gas transportation will lower due to the considerable time of loading and unloading of a gas carrier. The construction of a storage berth is proposed, and calculations of storage parameters and calculation of its buoyancy are made. The possibility of using the REFPROP vs. 9.1 software package to automate the selection of the composition of a multicomponent hydrocarbon mixture for further use at the selected range of temperatures and pressures is substantiated. The use of the system is considered in the example of phase equilibrium of a multicomponent hydrocarbon mixture. [ABSTRACT FROM AUTHOR]

We study the global phase behaviour of n-alkanes applying Wertheim's first order thermodynamic perturbation theory (TPT1). The molecules are modelled as homonuclear chains comprised of m freely jointed spherical segments interacting via the Lennard-Jones potential. Vega et al. [J. Chem. Phys. 116, 17 (2002)] have shown that the TPT1 is suitable to treat solid phases as well as fluid phases when model chains are considered, but that the adoption of a fully flexible chain model leads to the under-prediction of triple point temperatures and overestimation of the fluid ranges in comparison to experiment. Here, we propose a model in which a different number of segments are used to treat the fluid and the solid phase. The number of segments used to model the molecules in the fluid phase m f , and the LJ monomer potential parameters σ and ε are taken from published soft-SAFT values, whereas in the case of the solid phase a reduced temperature-dependent effective chain length m s (T ∗) is determined through a minimisation between theoretical and experimental liquid-solid phase equilibrium data. We refer to this model as effective-solid TPT1 (es-TPT1). We use the model proposed to calculate the solid–liquid–vapour phase diagrams of several n-alkanes and compare with experimental data. In the approach proposed, the conformation of chains in the solid phase is decoupled from the fluid phase, and an excellent description of the melting properties, as well as accurate predictions of the triple point temperatures for the n-alkanes examined is obtained. This simple solution provides an avenue to model the solid–liquid–vapour phase behaviour of other real substances in a TPT1 framework, and hence within the SAFT family of equations. [ABSTRACT FROM AUTHOR]

Formaldehyde is a highly reactive chemical that is usually sold and processed in the form of aqueous solutions, with methanol added for stability. In these solutions, formaldehyde reacts with the solvents to form a variety of reaction products, including oligomers. These chemical reactions can occur in the liquid and vapour phases and have a significant influence on the properties of formaldehyde-containing solutions. Of particular interest to industrial applications is the prediction of the vapour–liquid equilibria (VLE) in formaldehyde solutions, considering the chemical reactions. We use the SAFT-γ Mie group-contribution (GC) equation of state to obtain the fluid-phase behaviour of binary and ternary mixtures of formaldehyde with water and methanol. The oligomerisation reactions taking place in aqueous and methanolic solutions of formaldehyde are modelled implicitly using a physical approach, which is possible within the SAFT-γ Mie framework by adding association (reactive) sites that mediate the formation of the reaction products. Using this approach, the nature of the chemical speciation in formaldehyde + water, formaldehyde + methanol and formaldehyde + water + methanol mixtures is studied. A new group, CH 2 O, characterising formaldehyde within the SAFT-γ Mie GC approach, is developed. Experimental data for the VLE in binary mixtures of formaldehyde + water and formaldehyde + methanol are used to obtain the optimal unlike interaction parameters between the corresponding SAFT-γ Mie groups. The newly developed parameters are used to predict the VLE of ternary formaldehyde + water + methanol mixtures for a wide range of temperatures and pressures, with excellent agreement to experimental data. Additionally, the SAFT-γ Mie approach is shown to provide accurate predictions of the distribution of reaction species (oligomers) in binary and ternary mixtures containing formaldehyde. [ABSTRACT FROM AUTHOR]

The present study examines the co-micellization in different block copolymers (BCPs): P123 and F127 (with almost similar hydrophobic PO block but different hydrophilic %EO content). In varying concentration and in presence of NaCl, these BCP solutions in single and mix system displayed a variety of phases, i.e., blue point (BP), thermoreversible gel formation and cloud point (CP) with a noticeable sol–gel phase transition shift. The nanoscale micellar size distribution expressed as hydrodynamic diameter (Dh) was evaluated using dynamic light scattering (DLS). As F127 is larger than P123 and contains more EO groups, the micelle corona appears larger with greater Dh. The scattering profile from small-angle x-ray scattering (SAXS) offered information into the micellar dimensions employing SasView 4.2.2 program. The quercetin (QCT) solubilization articulated in encapsulation efficiency (EE%) and drug loading (DL%) followed the enhancement order: P123 > (P123 + F127) > F127 which was inferred from spectral and microscopy study. 5%w/v Pluronics® (P123 and F127) in single (pure) and mix environment depicting their micellar dimensions obtained from SAXS. [ABSTRACT FROM AUTHOR]

Almost 40% of undiscovered hydrocarbon reserves have high CO2 and H2S concentrations around the globe. So it is crucial to understand these hydrocarbon systems’ thermophysical properties for the excellent design of production facilities. An experimental investigation is conducted in this study to understand and evaluate the thermodynamic conditions of gas hydrate formation in natural gas systems with high CO2 levels gas and dominant multiphase (high CO2 level gases, deionized water, and crude oil). Three gas mixtures were chosen in this study to simulate natural gas with high CO2 content. The experiments are conducted within the critical pressure of the selected gas to avoid any phase change due to pressure. The impact of high CO2 levels in gas systems on the thermodynamic conditions of the gas hydrates was first explored. Then, the effect of a multiphase system was investigated after the addition of the oil phase into the system. The thermodynamic equilibrium conditions obtained from experiments were used to construct the Hydrate liquid–vapour Equilibrium (HLVE) curves, and the phase behaviour was studied. The details about the temperature variance and enthalpy are also clearly discussed. It has been discovered that gas mixtures with a higher CO2 content tend to promote compared to the pure methane gas system but inhibit compared the pure CO2 system. But in the multiphase system, all the gases show an inhibition effect compared to their respective pure gas system results.

The availability of sufficient amounts of form I of benzocaine has led to the investigation of its phase relationships with the other two existing forms, II and III, using adiabatic calorimetry, powder X-ray diffraction, and high-pressure differential thermal analysis. The latter two forms were known to have an enantiotropic phase relationship in which form III is stable at low-temperatures and high-pressures, while form II is stable at room temperature with respect to form III. Using adiabatic calorimetry data, it can be concluded, that form I is the stable low-temperature, high-pressure form, which also happens to be the most stable form at room temperature; however, due to its persistence at room temperature, form II is still the most convenient polymorph to use in formulations. Form III presents a case of overall monotropy and does not possess any stability domain in the pressure–temperature phase diagram. Heat capacity data for benzocaine have been obtained by adiabatic calorimetry from 11 K to 369 K above its melting point, which can be used to compare to results from in silico crystal structure prediction. [ABSTRACT FROM AUTHOR]

This study examined the phase behaviour and temperature-dependent viscosity of palm stearin and fully hydrogenated soybean oil (FHSBO) mixtures to understand the stability of FHSBO coatings on micronutrient premixes. The Hildebrand equation showed that palm stearin/FHSBO mixtures form liquid solutions, while DSC data indicated partial immiscibility in the solid phase. The melting temperatures and enthalpies of fusion are composition dependent, ranging from 67 °C and 138 J/g for 100 % FHSBO to 13 °C and 71 J/g for 100 % palm stearin. The Arrhenius model provided an excellent fit for the viscosities of the binary mixtures above their melting points, with activation energies of 26–27 kJ/mol and pre-exponential factors of 131–207 MPa.s. At the processing conditions of bouillon cubes, a binary fat coating can form on premix granules and contain approximately 70 % palm stearin at equilibrium. At processing temperatures of 30–60 °C, the premix fat coating contains 68–84 % liquid. • Palm stearin and fully hydrogenated soybean oil (FHSBO) form ideal liquid solutions. • Viscosities of palm stearin and FHSBO mixtures conform to the Arrhenius model. • FHSBO coatings must remain in a solid state to resist deformation and removal during processing. [ABSTRACT FROM AUTHOR]

New vapour–liquid–liquid and vapour–liquid equilibrium data to complement the existing ones are measured at six temperatures (308.15 K to 383.15 K) and at pressures up to 182.9 K using an analytic-static method with phases sampling via special valves (" AnTVisVarCap ", as defined by Prof. Ralf Dohrn and co-workers) for the carbon dioxide (1) + 1-hexanol (2) binary system. Four out of the six isotherm reported here are measured for the first time. The main component of the high-pressure setup is a 60 cm3 visual cell. The new isotherms are compared with the available literature which is also reviewed and analysed. It should be noted that among the data already published, only one other research group reported the compositions of both phases at equilibrium, as we did previously by using another experimental method. The new and literature data were modelled with Peng-Robinson (PR) and Soave-Redlich-Kwong (SRK) equations of state based on a semi-predictive procedure to reproduce as well as possible the minimum and the maximum of the critical curve(s) using one set of binary interaction parameters. The influence of critical data and acentric factors of pure components on the phase behaviour of their binary system is discussed. Although the values of the critical pressures and acentric factors of pure substances are not very different in the database we used, the models predict type III or IV phase behaviour with the same set of binary interaction parameters. This sensitivity, which was not observed for other systems we studied, could be explained by the alcohol structure and high asymmetry of the system. Therefore, we analysed in more depth the influence of the critical temperatures and pressures, as well as the acentric factors of carbon dioxide and 1-hexanol and exemplified for one temperature located above the system UCEP's temperature. [Display omitted] [ABSTRACT FROM AUTHOR]

The techno-economic evaluation of geothermal resources requires knowledge of the geofluid's thermophysical properties. While the properties of pure water and some specific brines have been studied extensively, no universally applicable model currently exists. This can result in a considerable degree of uncertainty as to how different geothermal resources will perform in practice. Geofluid modelling has historically been focused on two research fields: 1) partitioning the geofluid into separate phases, and 2) the estimation of the phases' thermophysical properties. Models for the two fields have commonly been developed separately. Recognising their potential synergy, we introduce GeoProp , a novel geofluid modelling framework, which addresses this application gap by coupling existing state-of-the-art fluid partitioning simulators, such as Reaktoro , with high-accuracy thermophysical fluid property computation engines, like CoolProp and ThermoFun. GeoProp has been validated against field experimental data as well as existing models for some incompressible binary fluids. We corroborate GeoProp's efficacy at modelling the thermophysical properties of geothermal geofluids via a case study on the heat content of different geofluids. Our results highlight the importance of accurately characterising the thermophysical properties of geofluids in order to quantify the resource potential and optimise the design of geothermal power plants. [ABSTRACT FROM AUTHOR]

Water scarcity is becoming a severe problem worldwide due to inadequate freshwater resources and swift population growth. Seawater desalination is one of the vital approaches to meet the demand for freshwater. However, energy and associated costs with conventional seawater desalination techniques are incentivizing non‐conventional water desalination processes. Water desalination using gas hydrates formation is one of the emerging non‐conventional processes. In this perspective article, recent advances in hydrate‐based seawater desalination (HBSD) have been critically analyzed to outline a future path towards a clean and efficient hydrate‐based desalination process. It provides a detailed comparison of various processes developed over decades, and measured desalination efficiencies with their process details. Moreover, the current challenges, limitations, and future perspectives of hydrate‐based desalination are also discussed. The study also recapitulates the thermodynamics and kinetics aspects of the hydrate‐based desalination process. In addition, various factors controlling the desalination efficiencies, such as control of the separation of hydrate crystals, salt deposition on hydrate particles, and hydrate morphology, were thoroughly investigated with their proposed process designs. The kinetics of hydrate formation is also assessed, with the possibility of a zero‐induction regime and its consequent impact on hydrate morphology. The current capabilities of the thermodynamics models (Gibbs energy minimization + electrolyte equation of state) were discussed using various commercially available software. Additionally, the role of hydrate promotors is also discussed, which can reduce the higher cost associated with the hydrate‐based desalination process. [ABSTRACT FROM AUTHOR]

Computation of the critical point of complex fluid mixtures is an important part of understanding their thermodynamic phase behaviour. While algorithms for these calculations are well established, they are often slow when the number of constituting components is large. In this work, we propose a new procedure to significantly accelerate critical point calculations by leveraging deep neural network (DNN) models. A DNN model for critical point predictions of a given mixture is first trained based on the critical points of such a mixture with various compositions. The predictions of the DNN model are then used to initialize both of the commonly used algorithms for mixture critical point calculations: root finding and global minimization. We demonstrate that when using the DNN-based predictions to initialize the root-finding-based and optimization-based algorithms, we can achieve 50-90% and 80-90% reductions in the number of required iterations, respectively. • Deep Neural Networks (DNN) can estimate the critical point of fluid mixtures. • These estimates can be used to initialize analytical calculations. • A 50 − 90 % reduction in the number of iterations can be obtained this way. [ABSTRACT FROM AUTHOR]

• The impact of pressure-dependent factor on crude oil cracking at high pressure conditions was investigated. • The produced fluids as pressure medium conduct a series of effects on crude oil cracking. • The relationship between fluid phase behaviours and pressure influences was elucidated. • Fluid pressure controls the occurrence of multi-phases oil and the accumulation of light oil and condensate in pores. An oil with an initial equivalent maturity of 0.74 % R o, was pyrolyzed in a closed gold tube pyrolysis system with added silica sand and no added water under simulated conditions spanning 0.7 %–2.1 % EasyRo. The internal fluid pressure, ranging from 0 to >150 MPa at individual maturities states of 1.0 %, 1.5 % and 2.1 % EasyRo, was controlled by increasing sample mass and setting external confining pressure (50, 100 and 150 MPa). Results indicate that the increasing fluid pressure initially promoted and then gradually retarded crude oil cracking. The free-radical reaction mechanism (hydrogen radical supply), free space of vessels, and characteristics of pressure medium control the influence of fluid pressure on the chemical reaction process. The decreasing free space of volume-constant vessels and the difference of hydrogen radicals supplied in various thermal maturity stages together gradually reduce the reaction rate of crude oil cracking. Thus, the yields of methane, wet gas, and light and heavy hydrocarbons increase at low fluid pressure ranges and then decrease at high-pressure conditions. Moreover, the physical controls of fluid phase behaviors include the evolution of fluid phase states influencing the increased rates of fluid pressure and fluid pressure influencing the production of multi-phase hydrocarbons. The increase in fluid pressure is faster in the saturated gas–liquid phase than in the unsaturated phase; thus, the phase behaviors induce the yields of product change. The increasing fluid pressure induces the occurrence of multi-phase hydrocarbons and accumulation of light oil and condensate. This study introduces a novel approach to investigate the influence of fluid pressure on reservoir oil cracking, emphasising phase behavior analysis, and shedding light on the evolution of organic matter in deep and ultra-deep strata. [ABSTRACT FROM AUTHOR]

[Display omitted] Glycolipids in biological membranes are ubiquitous and believed to be involved in the formation of ordered functional domains. However, our current knowledge about such glycolipid-enriched domains is limited because they are inherently difficult to characterize. We use grazing-incidence X-ray diffraction, isotherm measurements, and Brewster angle microscopy to investigate the phase behavior and miscibility in Langmuir lipid monolayers containing glycolipids. Glycolipid-enriched domains give rise to distinct diffraction patterns that allow for a systematic structural investigation and reveal a rich phenomenology, ranging from near-complete demixing to the formation of mixed domains with unique features. The phase behavior is governed by the headgroup chemistry and by the length and saturation of the tails. [ABSTRACT FROM AUTHOR]

There is an increasing demand for the design of complex bio-composites with customized structural characteristics for use in processed food products. Phase behaviour of these mixtures determines textural properties, encouraging the pursue of a rapid technique that can accurately quantify it. The present work tests the efficacy of confocal laser scanning microscopy (CLSM) coupled with image analysis software (Imaris), for the quantification of phase behaviour in complex tertiary systems. In doing so, it develops phase separated gels of agarose and gelatin supporting inclusions of canola oil. The polysaccharide was replaced with whey protein isolate (WPI) and the topology of the tertiary dispersion with gelatin and canola oil was also examined. Reproducible phase volume estimates were obtained, including those of the lipid phase, which were a close match to the actual concentrations added to the hydrocolloid gel. The approach could offer an alternative to the rheological estimation, via theoretical blending law analysis, of phase volumes in bio-composites. [ABSTRACT FROM AUTHOR]

Pyrrolidinium-based ionic liquids belong to the relatively common classes of these compounds; however, there are serious gaps in the knowledge and interpretation flaws of their physico-chemical properties, except for those containing the archetypal bistriflimide [NTf2] anion. Compounds combining the 1-butyl-1-methylpyrrolidinium cation [C4C1Pyrr] with various fluorinated sulfonate anions exhibit vast polymorphism, rendering the thermodynamic description even more complicated. Four 1-butyl-1-methylpyrrolidinium ionic liquids, available commercially in high purities, were subjugated to a combined calorimetric and crystallographic study with a special emphasis on establishing a complete interpretation of their phase behaviour.The samples were dried by vacuum heating and their purity was verified using the Karl Fischer titration and van't Hoff analysis of the melting peaks. Polymorphism was readily detected for all four compounds, but a complete description of their phase behaviour required an intensive and careful labour. Despite our experimental efforts, some of the polymorphs were found to be too elusive for a complete characterization by any of the used techniques. The obtained phase-transition temperatures and enthalpies were critically compared to the available literature with a variable agreement. While the existing thermodynamic data for [C4C1Pyrr][NTf2] were found complete and sensible, literature data for the other compounds were incomplete or ambiguous. Heat capacities of the four compounds were determined using a Tian-Calvet calorimeter, the results of which were in a good agreement with the existing adiabatic-calorimetric data for [C4C1Pyrr][NTf2]. Several crystal structures were newly resolved within the phase behaviour study and they are reported in the paper.

The synthesis of novel oligothiophene‐containing carbosilane‐siloxanes of linear or branched structure with conjugation lengths of 4–7 thiophene rings, flexible aliphatic spacers varying from C3 to C11, and various degrees of branching of end‐capping solubilizing groups is reported. The investigation of their phase behavior by differential scanning calorimetry and polarizing optical microscopy showed that although some of them can form liquid‐crystalline phases, the majority of the linear molecules exhibits a high degree of crystallinity, which decreases with increasing degree of branching. Aggregation studies in dilute solutions in toluene at different temperatures allowed determination of the temperature and concentration dependence of their dissociation. The investigation of thin films prepared from dilute solutions revealed the formation of fibril domains confirming aggregation of the molecules. [ABSTRACT FROM AUTHOR]

Thermoplastic polyurethane elastomers (TPUs) have been intensively used as hot-melt adhesives (HMAs) due to their adherence ability that can be applied on hard surfaces. To overcome their drawbacks, such as low peel strength and deformation, the performance improvement of the TPUs-HMAs has become a challenging issue. In this study, the enhancement properties of the TPUs-HMAs were achieved from the copolymerization of a soft-segment technique. Two types of polycarbonate diols (PCDs) were utilized for the TPU production as a co-diol of the soft segment. The properties and phase behaviour of the TPUs with various ratios of copolymerized soft segment were analysed. The compatibility between the different types of the PCDs is defined by the concentration of the hydrogen bonding interaction between the hard and soft phases and the dimensions of the hard domains. The homogeneous dispersion of the hard domains in the soft phase promotes better stress transfer enhancing the mechanical properties and adhesion properties. The peel strength is measured between the TPUs/stainless steel joint, in which the highest value is accomplished with the formulation of 60:40 wt% of copolymerized soft segment, which is associated with the superior mechanical strength and the optimum compatible properties of the soft segment. [ABSTRACT FROM AUTHOR]

The impact of simultaneous additions of cerium and manganese in ZrO 2 –SiO 2 binary oxides to enhance the ZrSiO 4 formation is investigated. The synthesis has been performed through sol-gel technique with the maximum concentration of ionic substitutions investigated being 20 wt % with respect to Zr4+ and Si4+. Analytical characterization techniques involving X-ray diffraction, Raman spectroscopy, Rietveld refinement, X-ray photoelectron spectroscopy, transmission and scanning electron microscopy have been used to investigate the phase behaviour, oxidation state of elements, elemental and morphological analysis of the resultant ZrSiO 4. The results ensured the ZrSiO 4 formation relatively at a low temperature ∼900 °C and consequently its crystallization behaviour indicated a steady enhancement, which is influenced by the dopant concentration and heat treatment conditions. 5 wt % manganese additions yield single phase ZrSiO 4 at 1100 °C while their excess additions led to their segregation at the grain boundaries of ZrSiO 4. Cerium additions until 5 wt % induced the lattice expansion of ZrSiO 4 and this has also facilitated the complete accommodation of manganese in ZrSiO 4. Cerium additions beyond 5 wt % led to the crystallization of CeO 2. The densification phenomenon of ZrSiO 4 has also been influenced by the incremental cerium and manganese additions. Simultaneous additions of cerium and manganese in ZrO 2 -SiO 2 binary oxide. [Display omitted] • 5 wt % Ce3+ and Mn2+ additions in ZrO 2 –SiO 2 system yield single-phase ZrSiO 4 at 1100 °C. • Mn2+ induces earlier ZrSiO 4 crystallization. • Ce3+ expands the occupancy limit of Mn2+ at the crystal lattice of ZrSiO 4. • Crystallization of CeO 2 at ZrSiO 4 matrix beyond 5 wt % additions. • Varied ZrSiO 4 densification as a function of enhanced Ce3+ and Mn2+ inclusions. [ABSTRACT FROM AUTHOR]

Using density functional theory for a simple fluid of hard spheres with a square-well attraction, we study the phase behaviour of the fluid confined in triply periodic porous material, where the pore space is bounded by a bicontinuous minimal surface. We combine our numerical results with the morphometric thermodynamics, an ansatz that expresses thermodynamic quantities as a linear combination of four additive geometrical terms, and analyse the dependency of the transition point between a liquid and a gas on the geometrical properties of the confining space. By demonstrating that the morphometric approach can be employed in order to account for the thermodynamic behaviour of a simple fluid in a complex porous material, we make the first step towards a better understanding of experimental observations that can help to characterise the pore space. [ABSTRACT FROM AUTHOR]

The need for a rapid and direct alternative to the rheology-based blending laws in quantifying phase behaviour in biopolymer composite gels is explored in this study. In doing so, the efficacy of confocal laser scanning microscopy (CLSM) paired with image analysis software – FIJI and Imaris - in quantifying phase volume was studied. That was carried out in a model system of agarose with varying concentrations of microcrystalline cellulose (MCC) in comparison to the rheological blending laws. Structural studies performed using SEM, FTIR, differential scanning calorimetry and dynamic oscillation in-shear unveiled a continuous, weak agarose network supporting the hard, rod-shaped MCC inclusions where the composite gel strength increased with higher 'filler' concentration. The phase volumes of MCC, estimated with the microscopic protocol, matched the predictions obtained from computerized modelling using the Lewis-Nielsen blending laws. Results highlight the suitability of the microscopic protocol in estimating the water partition and effective phase volumes in the agarose-MCC composite gel. [ABSTRACT FROM AUTHOR]

The self-assembly of lipid mixtures in aqueous solution was investigated by dissipative particle dynamics simulation. Two types of lipid molecules were modelled, where three mixed structures, i.e., the membrane, perforated membrane and vesicle, were determined in the self-assembly processes. Phase behaviour was investigated by using the phase diagrams based on the tail chain lengths for the two types of lipids. Several parameters, such as chain number and average radius of gyration, were employed to explore the structural formations of the membrane and perforated membrane in the dynamic processes. Interface tension was used to demonstrate the mechanical properties of the membrane and perforated membrane in the equilibrium state and dynamics processes. Results help us to understand the self-assembly mechanism of the biomolecule mixtures, which has a potential application for designing the lipid molecule-based bio-membranes in solutions.

The increasing risk of environmental pollution and health problems in the day-to-day life due to the usage of synthetic pesticides make the role of nanoemulsions very significant. The study is aimed at development of eco-friendly nanoemulsion of non-edible oil such as Karanj oil and Neem oil by using the Tween80 and PEG400 as surfactant and cosurfactant respectively. The phase behaviour of ternary mixtures and nanoformulations was studied by visual observation. The nanoemulsion was found to be stable for the period of one month at 30°C . The nanoemulsions were characterized by various physicochemical properties such as viscosity, surface tension, pH, droplet size, polydispersity index etc. The Larvicidal activity was studied under 24h of exposure against Aedes agypti and Culex quinquefasciatus larvaes. Rheological study shows the pseudoplastic flow behaviour. [ABSTRACT FROM AUTHOR]

Colloidal lipidic particles with different space groups and geometries (mesosomes) are employed in the development of new nanosystems for the oral delivery of drugs and nutrients. Understanding of the enzymatic digestion rate of these particles is key to the development of novel formulations. In this work, the molecular structure of the lipids has been systematically tuned to examine the effect on their self-assembly and digestion rate. The kinetic and phase changes during the lipase-catalysed hydrolysis of mesosomes formed by four synthetic cyclopropanated lipids and their cis -unsaturated analogues were monitored by dynamic small angle X-ray scattering and acid/base titration. It was established that both the phase behaviour and kinetics of the hydrolysis are greatly affected by small changes in the molecular structure of the lipid as well as by the internal nanostructure of the colloidal particles. [ABSTRACT FROM AUTHOR]

As the symbol of gemini surfactants, the spacer group connects two surfactant monomers and plays an important role in the self-assembling of gemini surfactants. Recent attention has been paid to the effects of spacer nature and length in aqueous systems. In this study, the aggregation behaviours of quaternary ammonium gemini surfactants 12-s-12 with different spacer length (s = 2, 3, 4, 5, 6, 8, 10, 12) have been investigated in the protic ionic liquid EAN. The micellization behaviour was characterized by surface tension measurement. With the help of small-angle X-ray scattering (SAXS), the size and shape of aggregates were verified. The spacer length effect could be reflected by the changes in the micellization and phase behaviours of 12-s-12/EAN systems. The critical packing parameter of gemini molecules would decrease monotonically with the spacer length, which is supported by SAXS results. Due to the charge screening effect of EAN, the aggregation behaviours of 12-s-12 would be mainly influenced by spacer length. Our results would be the important supplement to the spacer length effect of gemini surfactants in the nonaqueous systems. With the increase of spacer chain length, the reverse hexagonal lyotropic liquid crystal phase would transform into the micellar phase. [ABSTRACT FROM AUTHOR]

Aqueous mixtures of anionic and nonionic/cationic surfactants can form non-trivial self-assemblies in solution and exhibit macroscopic responses. Here, we investigate the micellar phase of pure and mixed aqueous solutions of Sodium Dodecyl Sulfate (SDS) and Dimethyldodecyl Amine Oxide (DDAO) using a combination of Small Angle Neutron Scattering (SANS), Fourier-Transform Infrared Spectroscopy (FTIR) and rheological measurements. We examine the effect of temperature (0–60 °C), on the 20 wt% SDS micellar solutions with varying DDAO (⩽ 5 wt%), and seek to correlate micellar structure with zero-shear solution viscosity. SANS establishes the formation of prolate ellipsoidal micelles in aqueous solutions of pure SDS, DDAO and SDS/DDAO mixtures, whose axial ratio is found to increase upon cooling. Elongation of the ellipsoidal micelles of pure SDS is also induced by the introduction of the non-anionic DDAO, which effectively reduces the repulsive interactions between the anionic SDS head-groups. In FTIR measurements, the formation of elongated mixed ellipsoidal micelles is confirmed by the increase of ordering in the hydrocarbon chain tails and interaction between surfactant head-groups. We find that the zero-shear viscosity of the mixed surfactant solutions increases exponentially with decreasing temperature and increasing DDAO content. Significantly, a master curve for solution viscosity can be obtained in terms of micellar aspect ratio, subsuming the effects of both temperature and DDAO composition in the experimental range investigated. The intrinsic viscosity of mixed micellar solutions is significantly larger than the analytical and numerical predictions for Brownian suspensions of ellipsoidal colloids, highlighting the need to consider interactions of soft micelles under shear, especially at high concentrations. [ABSTRACT FROM AUTHOR]

Series of oligomeric ionic liquid crystals (OILCs) based on various anions including bromide (Br−), tetrafluoroborate (BF4−), dodecylbenzenesulphonate (A-SO3−) and (+)-10-camphorsulphonate (D-SO3−) are synthesised by use of pyridine-containing monomers, terminal bromo-substituted alkanes and anion replacement reagents. The effect of anions on the chemical structure, liquid-crystalline behaviour, and ionic conductivity is investigated. The OILCs show various mesophases including smectic, hexagonal columnar and bicontinuous cubic phase due to the change in anions. These mesophase types are determined by two incompatible segments derived from ionic mesogens and flexible alkyl chains in the microstructure. For the OILCs based on A-SO3− and D-SO3− anions, a curvature of the interfaces between the layers arises due to the increased size of one segment, resulting in columnar and cubic mesophases. The ionic conductivity is investigated in the way that a lithium ion solution passing through the oriented OILC films at room temperature. For the OILC films with various anions, ionic conductivities of the measuring system increase a little in the order A-SO3− > D-SO3− > BF4−> Br−. The values based on A-SO3− anion films show nearly twofold increase compared with those based on Br- anions, which can be attributed to the effects of both ion migration and ionic channels in the microstructures. [ABSTRACT FROM AUTHOR]

Control of the nanostructure of self-assembled systems may be achieved through manipulation of surfactant molecular packing and interfacial curvature. In order to phase engineer the inverse micellar cubosomes in some monoolein-fatty acid systems, lipids with wedge shaped molecular geometry were incorporated to promote the formation of this phase, that is of interest as potential sustained released nanocarriers. Liquid crystalline nanoparticle dispersions of monoolein with some cis unsaturated fatty acids were prepared and their partial temperature-composition phase diagrams and structure were established using high throughput Small Angle X-ray Scattering (SAXS) and cryogenic transmission electron microscopy (cryo-TEM). The pH responsiveness of these systems was evaluated in the presence of phosphate buffered saline (PBS). The partial temperature-composition phase diagrams of five nanoparticle formulations containing monoolein and unsaturated fatty acids were established and identified the presence of micellar cubosomes in each of these systems. The results indicate that temperature, fatty acid concentration and structure, as well as pH all directly impact the formation and stability of this phase. Low energy inverse micellar cubic to emulsion phase transformations were identified in the monoolein with oleic acid and vaccenic acid systems at physiological temperatures that may be advantageous for staged therapeutic release strategies in nanomedicine. [ABSTRACT FROM AUTHOR]