Ternary Solutions Research Articles

Study of Thermodynamic Properties of l-Serine and l-Threonine in Aqueous Solutions of 1-(2-Carboxyethyl)-3-methylimidazolium Chloride [HOOCEMIM][Cl

The stability of amino acids in solutions containing electrolytes and the effect of ambient pH on their biological activity is an important research area. In this research work, the volumetric and transport properties of ionic liquid (IL) aqueous solution with special performance of 1-(2-carboxyethyl)-3-methylimidazolium chloride ([HOOCEMIM][Cl]) were studied. The selected IL acts as an electrolyte and allows the study of systems containing amino acids at acidic pH. In this work, the density, speed of sound and viscosity of binary and ternary solutions of IL in aqueous solution of amino acids in the structure of proteins, namely l-serine and l-threonine within IL molality range of (0.05, 0.07 and 0.09 mol·kg−1) were measured at 298.15 K. From these quantities, apparent molar volume, limiting apparent molar volume, apparent molar isentropic compression, limiting apparent molar isentropic compression, transfer standard volumes for amino acids from water to the aqueous IL solutions and viscosity B-coefficients were calculated using the equations of Redlich–Meyer and Jones–Dole. Close examination of literature indicates that there is no data for water activity for solution of l-serine + H2O at 308.15 and 318.15 K. In this way water activity, osmotic coefficient and vapor pressure were measured and using the interaction parameters of Wilson, NRTL, NRF-NRTL and UNIQUAC models, activity coefficient values of l-serine calculated.

14 years of lidar measurements of polar stratospheric clouds at the French Antarctic station Dumont d'Urville

Abstract. Polar stratospheric clouds (PSCs) play a critical role in the stratospheric ozone depletion processes. The last 30 years have seen significant improvements in our understanding of the PSC processes but PSC parametrization in global models still remains a challenge due to the necessary trade-off between the complexity of PSC microphysics and model parametrization constraints. The French Antarctic station Dumont d'Urville (DDU, 66.6∘ S, 140.0∘ E) has one of the few high latitude ground-based lidars in the Southern Hemisphere that has been monitoring PSCs for decades. This study focuses on the PSC data record during the 2007–2020 period. First, the DDU lidar record is analysed through three established classification schemes that prove to be mutually consistent: the PSC population observed above DDU is estimated to be of 30 % supercooled ternary solutions, more than 60 % nitric acid trihydrate mixtures and less than 10 % of water–ice dominated PSC. The Cloud–Aerosol Lidar with Orthogonal Polarization PSC detection around the station are compared to DDU PSC datasets and show a good agreement despite more water–ice PSC detection. Detailed 2015 lidar measurements are presented to highlight interesting features of PSC fields above DDU. Then, combining a temperature proxy to lidar measurements, we build a trend of PSC days per year at DDU from ERA5 (the fifth generation of European ReAnalysis) and NCEP (National Centers for Environment Protection reanalysis) reanalyses fitted on lidar measurements operated at the station. This significant 14-year trend of −4.6 PSC days per decade is consistent with recent temperature satellite measurements at high latitudes. Specific DDU lidar measurements are presented to highlight fine PSC features that are often sub-scale to global models and spaceborne measurements.

Improvement of surface morphology by optimizing the growth conditions in solution growth of SiC single crystal

In this study, 4H-SiC single crystal with 2-inch diameter was grown from Si-Cr-C ternary solution with Al addition and the surface morphology of specimen was improved through optimizing the growth conditions. The results suggested that the SiC single crystal grown at 0.1 MPa of He gas exhibits a relatively stable growth process with hexagonal shape and the growth rate is about 152 μm/h due to the appropriate thermal field distribution near the growth interface. In addition, the appearance of polycrystalline SiC precipitated around the seed crystal and the formation of solvent inclusions in the grown crystal could be significantly suppressed by using specially designed seed holder wrapped by BN cap. However, some pore or void defects can still be clearly observed in the grown crystal and possible improved ways aimed at reducing or eliminating pore defects are briefly summarized and the detailed research will be further discussed in the next step of our work.

Dielectric characterization studies of hydrogen-bonded polar liquids in nonpolar medium using cavity perturbation technique

The dielectric characteristics of polar substances like propan-1-ol, propionaldehyde, isopropyl amine & its equimolar ternary mixtures in benzene are examined at discrete microwave frequency region using the cavity perturbation technique at 6.218 GHz (J-band), 9.880 GHz (X-band), 16.331 GHz (P-band) and 24.951 GHz (K-Band) at room temperature. The minimum energy geometry optimization is performed at 6-311G+ (d, p), 6-311G++ (d, p) basis set with DFT(B3LYP) method for both pure as well as ternary mixtures of propan-1-ol, propionaldehyde & isopropyl amine liquid systems. The dipole moment(s) of these combinations are evaluated using Higasi's approach and verified with theoretical data. The average relaxation times of the ternary solutions are calculated using the Cole-Cole plots. The mean molecular polarizability values of distinct systems of propan-1-ol, propionaldehyde, isopropyl amine, and their ternary solutions are calculated with Lippincott-δ function model. The findings are described through the molecular association between the components by hydrogen bonding.

Synthesis, structural stability and phase diagram of BiFeO3–CaSnO3 ceramics

BiFeO 3 -based materials have received extensive attention in electronic device applications due to their high Curie temperature and large electromechanical response. In this study, new solid solutions of (1- x )BiFeO 3 - x CaSnO 3 (BF-CS) ceramics were successfully synthesized via conventional solid-state reaction method. With increasing CS content, the ceramics exhibit a single-phase perovskite and the structure changes from a main rhombohedral phase with a small amount of impurity phase to a stable rhombohedral phase and then to MPB region separating the rhombohedral and orthorhombic phases in the composition of 0 ≤ x ≤ 0.15, indicating that introducing CS can stabilize the perovskite structure formed in the sintering process. Unfortunately, the solid solubility limit of CS into BF perovskite structure is reached when x > 0.15. The dielectric peak associated with oxygen vacancies become weaker and finally disappear at x = 0.15. Moreover, the ceramics with x = 0.12–0.15 feature saturated and square-shaped P - E hysteresis loops with increased polarization can be attributed to effectively promote domain switching process at MPB, in which the highest piezoelectric coefficient d 33 = 259 pC/N can be ascribed to the combined effect of coexistence phases, high relative bulk density and low leakage current. In particular, a partial phase diagram is constructed in terms of temperature and composition, which helps to understand the structure-property relations. The distinct structures and phase transition behavior on each side of the vertical MPB line offer the guidelines and strategy to design other BF-based binary or ternary solid solutions with enhanced piezoelectric property in high temperature application.

Activation of Viscous Flows of Water–Acetone–Methyl Ethyl Ketone Solutions with High Contents of Water, Compared to Water–Alcohol–Acetone Solutions

Values of kinematic viscosity and density are determined for water–acetone–methyl ethyl ketone solutions for the first time in the region of high contents of water and the 20–40°C range of temperatures. Results are used to calculate the molar kinematic viscosity (νm), the Gibbs energy of viscous flow activation (ΔG≠νΔ), and the entropy of viscous flow activation. The viscometric characteristics of this system are compared to those of water–ethanol–acetone, water–2-propanol–acetone, and water–2-butanol–acetone systems studied earlier. Dependences on the concentration of one organic component at a fixed content of a second are presented for different properties. The viscometric parameters of ternary solutions with methyl ethyl ketone, calculated based on size/molecular weight of the components (νm and ΔG≠νΔ), are close to those obtained for solutions with ethanol but notably higher for solutions with 2-propanol and 2-butanol. It is concluded that molecules participating in the formation of intermolecular hydrogen bonds as proton donors (alcohols) raises viscosity more than an increase in size/mass (methyl ethyl ketone). Different ways of calculating the entropy of viscous flow activation (ΔS≠νΔ) are compared on the basis of literature data. It is found that ΔS≠νΔ is higher than that of water in the studied range of concentrations of the ternary water–acetone–methyl ethyl ketone system, which is also typical of other aqueous solutions.

Investigating the H-bond network of ternary (xylitol-water-acetic acid) aqueous solutions by Raman spectroscopy and DFT

Xylitol, an important sugar substitute, has been widely used in the food and medicine industries, so it is necessary to study the weak interactions between xylitol and other substances. Herein, the H-bonds of ternary solutions comprising xylitol, water, and acetic acid were investigated by Raman spectroscopy and density functional theory (DFT). The generation of an H-bond network between the O–H functional group of xylitol and the C=O of acetic acid was confirmed by a significant new Raman peak at 1639 cm−1. In addition, the H-bond network of water was deformed by the intensive water-acid interactions, leading to a robust Raman peak blue-shift of the O–H stretching vibration. The results are of significance for understanding the effect of acid on xylitol and help further study the H-bond network in complex ternary solutions.

A novel triple templates molecularly imprinted biosensor assisted by second-order calibration methods based on generation of second-order hydrodynamic linear sweep voltammetric data for simultaneous biosensing of insulin, proinsulin and C-peptide: Application to comparing PARAFAC2 and PARASIAS

In this work, a novel, very sensitive and selective electrochemical biosensor was fabricated based on excellent modification of a thick-film boron doped diamond electrode (TFBDDE) for simultaneous biosensing of insulin (IN), proinsulin (PIN) and C-peptide (CPT). The TFBDDE was modified with multiwalled carbon nanotubes-fullerene C60-graphene-ionic liquid (MWCNTs-C60-GR-IL). Then, IN, PIN and CPT as template molecules were mixed with N-methacryloyl-(L) 3-histidine methyl ester, 2-hydroxyethyl methacrylate and ethylene glycol dimethacrylate, and drop-casted onto the sensor surface for the synthesis of triple templates molecularly imprinted polymers (TTMIPs) by ultraviolet polymerization method. After individual immersion of the biosensor with IN, PIN and CPT, its hydrodynamic linear sweep voltammetric (HLSV) responses were recorded. Immersion of the biosensor in a ternary solution of IN, PIN and CPT generated a single HLSV response which forced us to use multi-way calibration methods for simultaneous determination of IN, PIN and CPT based on generation of second-order HLSV data at different step potentials. Building three-way calibration models by PARAFAC2 and PARASIAS was performed, and the results confirmed superiority of PARASIAS than PARAFAC2 in simultaneous determination of IN, PIN and CPT in the ranges of 1–16 pM, 4–25 pM and 8–88 pM, respectively, in both artificial and real human serum samples. According to the results obtained in this work, the biosensor assisted by PARASIAS can be used as a reliable device for simultaneous determination of IN, PIN and CPT in serum samples.

Study of gallic acid antioxidant molecule in interaction with solvents, aiming its utilization as a stabilizer of magnetic nanoparticles in suspensions

Gallic acid (GA) molecule was studied by quantum-chemical and experimental approaches since it is a remarkable antioxidant product that could be used to improve the biocompatibility of magnetite nanoparticles in colloidal suspension. Computational modeling has evidenced significant dipolar character as well as good reactivity and stability. The preparation of magnetite nanoparticles capped with GA has resulted in stable colloidal suspension as revealed by Transmission Electron Microscopy investigation. A solvatochromic study was carried out on GA in binary and ternary solutions, evidencing the coexistence of the main types of universal solute–solvent interactions. Based on the spectral behavior in protic and polar solvents the dipole moment vector in the excited state was found.

Insights into the ultra-high temperature solid solutions Hf-Ta-C-N quaternary system using high-throughput calculation

We investigated the structure, elastic, and thermodynamic properties of Hf-Ta-C-N solid solutions using high-throughput density functional theory calculations. The results of the elastic and mechanical properties indicate that increasing the nitrogen content increases the ductility of solid solutions; it also increases the elastic moduli of solid solutions in a specific range of nitrogen contents. The results indicate that the ternary and quaternary solid solutions of the Hf-Ta-C-N system have excellent formability, elastic, and thermal properties. In addition, thermodynamic analyses were performed to obtain temperature-dependent stable phase diagrams of the Hf-Ta-C-N quaternary system. This investigation was performed to determine the suitability of Hf-Ta-C-N quaternary solid solutions in high temperature condition, which was veiled in previous studies. In total, 51 related phases were studied, including 16 solid solutions and four elemental phases (Hf, Ta, C, and N2(g)). Our results indicate that the nitrogen-rich solid solutions can appear even at room temperature. The solid solutions covered a large area of the Hf-Ta-C-N phase spaces, regardless of temperature. As the temperature increases, the stable phase shifts from Ta and N to the Hf and C rich phases.

Unveiling the salting effects of choline chloride on aqueous polymer solutions

The salting-in and salting-out phenomena occurring in aqueous systems composed of choline chloride (ChCl) and water-soluble polymers were deeply scrutinized in this work. For this purpose, four ternary systems of {polymer + ChCl + water} were subjected to vapor-liquid equilibrium study by the isopiestic measurements at 25 °C. The polymers used are polyethylene glycol 400 (PEG400), polyethylene glycol 10,000 (PEG10000), polypropylene glycol 400 (PPG400), and polyvinylpyrrolidone 10,000 (PVP10000). Deviations of water isoactivity curves from the linear isopiestic relation (LIR) were considered as a benchmark to identify the dominant interactions and the salting effects occurring in the systems under investigation. Ternary aqueous solutions of PEG400/PEG10000/PVP10000 + ChCl showed positive deviations from the LIR, indicating the favorable polymer-ChCl interactions in these systems, and thus the occurrence of the salting-in effect in the concentration range investigated in this work. The strength of the co-solvency effect of ChCl on the aqueous polymer solutions decreases in the order PVP10000 > PEG10000 > PEG400. On the other hand, the aqueous system of PPG400 + ChCl exhibited negative deviations from the LIR in the monophasic region, demonstrating the unfriendly and incompatible behavior of ChCl with PPG in aqueous media resulting in the salting-out effect. The binodal curve determining the boundary between the monophasic and biphasic regions was obtained for the PPG400-ChCl aqueous biphasic system. It was found that the water isoactivity curves in the biphasic region of this system have positive deviations from the LIR due to the partial dehydration of the solutes by phase splitting.

A Novel Cathode Material Synthesis and Thermal Characterization of (1-x-y) LiCo1/3Ti1/3Fe1/3PO4, xLi2MnPO4, yLiFePO4 Composites for Lithium-Ion Batteries (LIBs)

Lithium-ion batteries are known for their high efficiency for storing electrical energy, especially for hybrid vehicles. In this research, the development of mixture composites in the cathode electrode of LIBs has been discussed and designed based on ternary solid solutions. We have given a novel synthesis and method preparation of cathode electrode materials to reduce costs while increasing the efficiency and simultaneity for the future of these technologies. The major problem in the LIBs is related to LiCoO2 as a popular cathode material that, although it has a high efficiency, is expensive and very toxic. Therefore, the usage of a lower weight of cobalt compared to the LiCoO2 cathode material is economically advantageous for this research. Several samples of the (1-x-y) LiCo1/3Ti1/3Fe1/3PO4 xLi2MnPO4 and yLiFePO4 system were synthesized via sol-gel experiments. Various stoichiometric amounts of the LiNO3, Li2MnPO4, Mn (Ac)2. 4H2O, Co (Ac)2.4H2O, Ti(NO3)2.6H2O and LiFePO4 have been used for several compositions of chrome, manganese, cobalt and titanium in 28 samples of (1-x-y) LiCo1/3Ti1/3Fe1/3PO4. By using thermal characterization, five samples have been selected due to their conditions in viewpoints of capacity and cyclability as well as activation energy, which is one of the major factors. These composites exhibited fairly consistent charge/discharge curves during the electrochemical testing. From the viewpoint of the physical and chemical properties, among these samples, the Li1.501Co0.389Ti0.055Fe0.055Mn0.501PO4 structure has a high efficiency compared to other compositions.

Enhancing the relaxor character in K0.5Bi0.5TiO3 based ternary system for energy storage applications

Lead-based ferroelectric materials dominate the electronic industry due to their possible applications in sensors, actuators, advanced storage materials, microwave devices, and MEMS. Due to the toxicity of lead, there is a need for the development of environmentally compatible alternatives. Lead-free ternary solid solutions of (1−2x)K0.5Bi0.5TiO3-xBaTiO3-xLiNbO3 (KBLN100x) with x = 0.03, 0.05, 0.07, and 0.09 are synthesized using a standard solid-state reaction method. X-ray diffraction studies confirm the pseudocubic structure of the samples. Structural, Raman, dielectric and piezoelctric studies indicate that a normal to relaxor ferroelectric transition occurs as dopant concentration increases, and it is attributed to the increase in charge fluctuation and site disorder that resulted in the reduction in correlation lengths of the inbuilt dipole moments. A recoverable energy density of 1.3 J/cm3 was achieved for the KBLN7 sample, making it an attractive candidate in the energy storage realm. A strain value of 0.17% with Smax/Emax of 218 pm/V is observed for KBLN3 sample, indicating that K0.5Bi0.5TiO3 (KBT)-based systems can be used for actuator applications on further improvement. The normal-relaxor crossover of KBT with appropriate dopants indicates that KBT-based systems are efficient for both actuator and energy storage applications on improvising and tuning as required.

Synthesis, crystal structure and IR investigation of Na2SeO4·H2SeO3

From the saturated ternary solution (Na 2 SeO 4 + CdSeO 4 )(aq) at 298 K, which were vigorously stirred for two days, a mixture of two phases: Na 2 Cd(SeO 4 ) 2 ·2H 2 O (nanoparticles) and a new phase, Na 2 SeO 4 ·H 2 SeO 3 were obtained. From the new phase a single crystal was cast. The composition of the new phase was identified by means of the X-ray diffraction, powder X-ray analysis and the infrared spectroscopy methods. Crystal data for H 4 Na 4 O 14 Se 4 (M =635.83 g/mol): monoclinic, space group P2 1 /c, a = 8.5638(6) Å, b = 6.9665(5) Å, c = 11.1596(8) Å, β = 90.149(7)°, α = γ = 90.00°, V = 665.78(8) Å 3 , Z = 2, T = 293(2) K. The IR spectra was recorded and analyzed.

Generic bond energy formalism within the modified quasichemical model for ternary solutions

The Modified Quasichemical Model in the Pair Approximation (MQMPA) can effectively capture the thermodynamic features of a binary solution with Short-Range Ordering (SRO). If the model is used to treat a ternary solution, a geometric interpolation method must be employed to extend the bond energy expression from binary to ternary formalism. The aim of the present work is to implement such extension by means of a generic geometric interpolation approach. The generic method is unbiased and can be transformed into the widely used Kohler, Toop and Muggianu approaches with special interpolation parameters. The interpolation parameters can be calculated by the integration method as well as be optimized by ternary experimental data. The generic bond energy formalism (GBEF) has thus been derived to provide the MQMPA great flexibility to describe ternary solutions with complex configurations. Moreover, the GBEF is more concise than the formula derived by a combinatorial Kohler-Toop method. The concise GBEF is in the respect more conveniently programmed. Eventually, the Cu-Li-Sn liquid where both SRO and clustering among atoms occur is employed to validate the effectiveness and reliability of the GBEF within the MQMPA.

Zein inclusion changes the rheological, hydrophobic and mechanical properties of agar/konjac glucomannan based system

The practical characteristics (rheological, hydrophobic, and mechanical) of biopolymer matrix are essential for its application in food. This work discloses how zein incorporation alters these characteristics of agar/konjac glucomannan (KGM) based matrix. The zein particles formed non-intensive interactions with hydrophilic agar/KGM molecules and thus weakened the chain entanglements in the agar/KGM/zein (AKZ) ternary solutions, which allowed reductions in the zero-shear viscosity (from 4800 to 600 mPa s), sol-gel transition point (Tgel, from 39 to 35 °C) and storage modulus (from about 16000 to ∼1000 Pa) of the resulting AKZ ternary gels. Also, such effects tended to enhance the agar aggregation (zein content: <12%) and the zein crystalline structure (zein content: >12%), reducing the dissolution rate and swelling ability of the acquired AKZ films (dehydrated gels) but increasing their Tg (ca. 10 °C higher). The tensile strength and elongation at break of the composite films reached ca. 70–80 MPa and ca. 5%–7%, respectively. The results here may facilitate the development of agar/KGM-based composites (solution, gel or film) with desirable performance.

A Neural Network Approach to Predict Gibbs Free Energy of Ternary Solid Solutions

We present a data-centric deep learning (DL) approach using neural networks (NNs) to predict the thermodynamics of ternary solid solutions. We explore how NNs can be trained with a dataset of Gibbs free energies computed from a CALPHAD database to predict ternary systems as a function of composition and temperature. We have chosen the energetics of the FCC solid solution phase in 226 binaries consisting of 23 elements at 11 different temperatures to demonstrate the feasibility. The number of binary data points included in the present study is 102,000. We select six ternaries to augment the binary dataset to investigate their influence on the NN prediction accuracy. We examine the sensitivity of data sampling on the prediction accuracy of NNs over selected ternary systems. It is anticipated that the current DL workflow can be further elevated by integrating advanced descriptors beyond the elemental composition and more curated training datasets to improve prediction accuracy and applicability.

Quantitative and structural analysis of water association in water-lithium bromide-1,3-dimethylimidazolium chloride mixtures

In this work we report on the quantitative and structural analysis of the water association in water-lithium bromide-1,3-dimethylimidazolium chloride mixtures using multivariate curve resolution based on alternating least squares (MCR-ALS) of Near Infrared (NIR) spectra and Molecular Dynamics (MD) simulations. (NIR + MCR) methodology was used to determine the bulk water amount, as well as the mole ratio between the H2O/absorbent of the solvated structures. Measurements were performed for ternary mixtures prepared with absorbent mole fraction (LiBr + [Dmim][Cl]) from 0 to 0.5987 and the MD simulations were carried out at selected compositions within this concentration range. The results revealed the existence of three water chemical environments: bulk water in absence of solutes, bulk water coexisting with solvated water and solvated water. The comparative analysis of results with those obtained for binary mixtures (H2O + LiBr) and (H2O + [Dmim][Cl]) evidenced that the water amount that remains as bulk water in ternary solutions is higher than in binary mixtures. Classical MD simulations for five different concentrations of absorbent confirmed that water environment evolves from being essentially coordinated with other water molecules in the most diluted system, to being mainly surrounded by monoatomic ions for the most concentrated mixture. Furthermore, higher interaction between the ions appears with increasing the absorbent mole fraction, which is confirmed by Car-Parrinello MD simulations.

Influence of alkali metals on water dynamics inside imidazolium-based ionic liquid nano-domains.

The global need to expand the design of energy-storage devices led to the investigation of alkali metal - Ionic Liquid (IL) mixtures as a possible class of electrolytes. In this study, 1D and 2D Nuclear Magnetic Resonance (NMR) and Electrochemical Impedance Spectroscopy (EIS) as well as Molecular Dynamics (MD) simulations were used to study the intermolecular interactions in imidazolium-based IL - water - alkali halide ternary mixtures. The 1H and 23Na 1D and 1H DOSY NMR spectra revealed that the presence of small quantities of NaCl does not influence the aggregation of water molecules in the IL nano-domains. The order of adding ionic compounds to water, as well as the certain water and NaCl molecular ratios, lead to the formation of isolated water clusters. Two ternary solutions representing different orders of compounds mixing (H2O+ IL + NaCl or H2O+ NaCl + IL) showed a strong dependence of the initial solvation shell of Na+ and the self-clustering of water. Furthermore, the behaviour of water was found to be independent from the conditions applied during the solution preparation, such as temperature and/or duration of stirring and aging. These findings could be confirmed by large differences in the amount of ionic species, observed in the ternary solutions and depending on the order of mixing/solute preparation.

The influence of cross-interactions between dilute cosolutes upon liquid interfaces.

We employ a statistical mechanical dilute solution theory (DST) and lattice Monte Carlo simulations to investigate the interfacial properties of ternary solutions with a dominant solvent and two dilute cosolutes. We consider cosolutes with weak interfacial preferences in order to focus on the impact of cross-interactions between the two cosolute species. When the cross-interaction is properly balanced, the two cosolutes make independent, additive contributions to both bulk and interfacial properties. Conversely, repulsive cross-interactions slightly enhance the interfacial preference of both solutes. In contrast, attractive cross-interactions reduce interfacial preferences and can convert weak surfactants into weak depletants. We observe a particularly interesting transition in the symmetric case of two equivalent self-repelling cosolutes with attractive cross-interactions. In this regime, the major cosolute acts as a weak surfactant in order to avoid repulsive self-interactions, while the minor cosolute acts as a weak depletant in order to form attractive cross-interactions. The two equivalent cosolutes switch roles depending upon their relative concentration. DST very accurately describes the surface tension and surface excess of simulated lattice solutions up to molar concentrations. More importantly, DST provides quantitative and qualitative insight into the mechanism by which cosolute interactions modulate interfacial preferences.