Respective Binary Systems Research Articles

Thermodynamic Modeling of the Drowning-Out Crystallization Process for LiOH and CHLiO2

This study focuses on the thermodynamic modeling of the crystallization by the drowning process for two lithium salts: lithium hydroxide (LiOH) and lithium formate (CHLiO2). The modeling involves utilizing thermodynamic properties, such as the activity, osmotic, and solubility coefficients, within the ternary systems of LiOH + cosolvent + water and CHLiO2 + cosolvent + water, as well as their respective binary constituent systems. Ethanol is chosen as the cosolvent for both salts, facilitating a comparative analysis. Given the limited availability of thermodynamic data for lithium formate with different cosolvents, the study aims to address this gap. The modified Pitzer model was employed for the modeling process, where the parameters were successfully obtained for both systems, with a deviation of less than 1%. Additionally, the mass and energy balance for the drowning-out crystallization process of both salts was performed.

Correlating Acceptor Structure and Blend Nanostructure with the Photostability of Nonfullerene Organic Solar Cells

The formation of photoinduced traps resulting in the loss of electron mobility deteriorates the performance of organic solar cells under continuous light soaking. The genesis of these loss mechanisms is elucidated by examining the structural stability of halogenated ITIC derivative films and the phase behavior of the respective binary systems by blending with the donor polymer PBDBT‐2F. Under constant illumination, ITIC‐4Cl is found to maintain its structural integrity, whereas fluorine on the peripheral moieties of ITIC‐4F undergoes chemical substitution to form a mixture of ITIC and ITIC‐4F. Thermal analysis of the light‐soaked binary films reveals that ITIC‐4Cl loses its crystalline phase while the crystallinity of ITIC‐4F does not undergo changes. Further, it is shown that the addition of a small amount of ITIC‐4F as a third component hinders the loss of ITIC‐4Cl crystalline phase in bulk heterojunction blends through the formation of cocrystals. These results suggest that long‐range ordering of NFAs does not necessarily improve the photostability of organic solar cells and that the addition of a third component, irrespective of the crystalline nature, can prevent changes in bulk heterojunction blend nanostructure.

Chemical Characterization and Biological Evaluation of New Cobalt(II) Complexes with Bioactive Ligands, 2-Picolinehydroxamic Acid and Reduced Schiff Base N-(2-Hydroxybenzyl)alanine, in Terms of DNA Binding and Antimicrobial Activity.

Five new heteroligand cobalt(II) complexes with 2-picolinehydroxamic acid and reduced Schiff base, N-(2-hydroxybenzyl)alanine, were formed in an aqueous solution over a wide pH range. The coordination properties of ligands towards the metal ion were determined using a pH-metric method, and then the speciation model was confirmed by UV–Vis studies. A stacking interaction between the Schiff base phenol ring and the 2-picolinehydroxamic acid pyridine ring was found to improve the stability of the heteroligand species, indicating more effective coordination in mixed-ligand complexes than in their respective binary systems. The antimicrobial properties of heteroligand complexes were determined against Gram-negative and Gram-positive bacteria, as well as fungal strains. The formulation demonstrated the highest bacteriostatic and bactericidal activity (3.65 mM) against two strains of Gram-negative Helicobacter pylori bacteria and towards Candida albicans and Candida glabrata; this is important due to the potential co-existence of these microorganisms in the gastric milieu and their role in the development of gastritis. The binary complexes in the cobalt(II)—2-picolinehydroxamic acid system and 2-picolinehydroxamic acid were not cytotoxic against L929 mouse fibroblasts, neither freshly prepared solutions or after two weeks’ storage. By comparison, the heteroligand complexes within the range 0.91–3.65 mM diminished the metabolic activity of L929 cells, which was correlated with increased damage to cell nuclei. The concentration of the heteroligand species increased over time; therefore, the complexes stored for two weeks exhibited stronger anticellular toxicity than the freshly prepared samples. The complexes formed in an aqueous solution under physiological pH effectively bound to calf thymus DNA in an intercalative manner. This DNA-binding ability may underpin the antimicrobial/antifungal activity of the heteroligand complexes and their ability to downregulate the growth of eukaryotic cells.

Assessment of the Ti-rich corner of the Ti-Si phase diagram using two sublattices to describe the Ti5Si3 phase

Abstract The thermodynamic optimization of Ti-X-Si systems requires that their respective binary systems be constantly updated. The most recent assessments of the Ti-Si phase diagrams used three sublattices to describe the Ti5Si3 phase. The stable version of this phase diagram indicated the presence of Ti(β)+Ti5Si3→Ti3Si and Ti(β)→Ti(α)+Ti3Si reactions in the Ti-rich corner, while the metastable version featured the presence of a Ti(β)→Ti(α)+Ti5Si3 reaction. The present investigation assessed these phase diagrams using two sublattices to describe the Ti5Si3 phase in order to simplify the optimization of Ti-X-Si systems.

Photocatalytic TiO 2 /porous BNNSs composites for simultaneous LR2B and Cr (VI) removal in wool dyeing bath

Abstract Titanium dioxide/porous boron nitride nanosheets (TiO 2 /P-BNNSs) were prepared to remove dyes (Lanaset Red 2B, LR2B) and heavy metals (hexavalent chromium, Cr (VI)) simultaneously in a simulated wool dyeing bath where pollutants (LR2B or Cr (VI)) and auxiliaries were simultaneously presented. Characterisations of TiO 2 /P-BNNSs were carried out by X-ray diffraction (XRD), Flourier transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM) and N 2 adsorption desorption equilibrium. Application of TiO 2 /P-BNNSs for the treatment of LR2B alone, Cr (VI) alone and their mixture in the simulated wool dyeing bath was discussed. Both LR2B and Cr (VI) removal were decreased in the ternary system (LR2B/Cr (VI)/(TiO 2 /P-BNNSs)) compared with those in their respective binary systems (LR2B/(TiO 2 /P-BNNSs) or Cr (VI)/(TiO 2 /P-BNNSs)) in the simulated wool dyeing bath. In spite of these decreases, simultaneous LR2B and Cr (VI) removal was achieved after 5 successive cycles of use of TiO 2 /P-BNNSs, which particularly maintained the durability for LR2B removal, implicating their potential for real wool dyeing effluent treatment.

Investigation of the Mg-Rich Part of the Mg-Dy-Sm Phase Diagram

Constitution of the Mg-rich part of the ternary phase diagram of Mg with two rare-earth metals, Mg-Dy-Sm was experimentally investigated for the first time using optical and scanning electron microscopy (SEM) with electron probe microanalysis (EPMA), x-ray diffraction and differential thermal analysis. In equilibrium with Mg solid solution only two solid phases were found, each of them being the riches by Mg compound in the respective binary systems, Mg24Dy5 and Mg41Sm5. Each of these compounds can also dissolve some other rare-earth metal. There is significant combine solubility of Dy and Sm in Mg solid solution, which decreases with lowering temperature. In the studied part of the Mg-Dy-Sm system one invariant four-phase equilibrium of L + (Mg24Dy5) ⇆ (Mg) + (Mg41Sm5) exists, which takes place at 535 °C. A number of isothermal partial sections and one temperature-composition section of the Mg-Dy-Sm phase diagram were constructed.

Assessment of the Ti-Rich Corner of the Ti-Si Phase Diagram: The Recent Dispute About the Eutectoid Reaction

The thermodynamic optimization of Ti-Si-X systems requires that their respective binary systems are constantly updated. The Ti-Si system has been experimentally investigated since the 1950s and these critical experimental data can be employed to calculate the Ti-Si phase diagram using thermodynamic modeling. The most recent assessment of the Ti-Si system was performed in 1998, showing the presence of stoichiometric Ti3Si as phase. In the light of the dispute over the stability of Ti3Si phase in the eutectoid reaction of the Ti-Si and Ti-X-Si systems, the present work assessed the Ti-rich corner of the stable (featuring Ti3Si phase) and metastable (featuring Ti5Si3 phase) Ti-Si phase diagrams. The phase boundaries, the values of the error of the least-square method of the optimization procedure and the relative standard deviation of the calculated variables of the assessed diagrams; and previous investigations were discussed in order to inspire further experimental work on the eutectoid reaction of the Ti-Si phase diagram.

Thermodynamic modeling of the Ga–Pt–Sb system

The Ga–Pt–Sb system was modeled using the CALPHAD (CALculation of PHAse Diagram) technique. Solution phases, liquid, fcc(Pt) and rhom(Sb), of the Ga–Pt–Sb ternary system were modeled with the substitutional solution model. The compounds, Ga6Pt, Ga7Pt3, Ga2Pt, Ga3Pt2, GaPt, Ga3Pt5, and GaPt2 of the Ga–Pt system, and PtSb2, PtSb, Pt3Prod. Type: FTPSb2, and Pt7Sb of the Pt–Sb system, were treated as line compounds Ptm(Ga,Sb)n in the Ga–Pt–Sb system. The compounds Ga3Pt and Pt5Sb were treated as (Ga%,Pt,Sb)3(Ga,Pt%) and (Pt%,Sb)5(Ga,Pt,Sb%) in the Ga–Pt–Sb system on the basis of thermodynamic models of the respective binary system. A set of self-consistent thermodynamic parameters was obtained. Using these thermodynamic parameters, the experimental isothermal section phase relation at 773K, the vertical sections at 25at% Pt, the GaPt–GaSb, Ga2Pt–GaSb, Ga7Pt3–GaSb, and GaPt–PtSb2 sections and the partial invariant reactions in the Ga–Pt–Sb system were well reproduced.

Characterization of σ-hole interactions in 1:1 and 1:2 complexes of YOF2X (X = F, Cl, Br, I; Y = P, As) with ammonia: competition between halogen and pnicogen bonds

Ab initio calculations at the MP2/aug-cc-pVTZ level of theory are performed to examine 1:1 and 1:2 complexes of YOF2X (X = F, Cl, Br, I; Y = P, As) with ammonia. The YOF2X:NH3 complexes are formed through the interaction of the lone pair of the ammonia with the σ-hole region associated with the X or Y atom of YOF2X molecule. The calculated interaction energies of halogen-bonded complexes are between −1.06 kcal/mol in the POF3···NH3 and −6.21 kcal/mol in the AsOF2I···NH3 one. For a given Y atom, the largest pnicogen bond interaction energy is found for the YOF3, while the smallest for the YOF2I one. Almost a strong linear relationship is evident between the interaction energies and the magnitudes of the positive electrostatic potentials on the X and Y atoms. The results indicate that the interaction energies of halogen and pnicogen bonds in the ternary H3N:YOF2X:NH3 systems are less negative relative to the respective binary systems. The interaction energy of Y···N bond is decreased by 1–22 %, whereas that of X···N bond by about 5–61 %. That is, both Y···N and X···N interactions exhibit anticooperativity or diminutive effects in the ternary complexes.

Production and characterization of Al-Cu and Al-Ni nanoparticles

ABSTRACTThe present work deals with the production and characterization of metal and bimetallic nanopowders.The electric explosion wire method for production of metal nanopowders is presented. The method enables to produce both metal and bimetallic nanoparticles (BMNP) with controlled content of metals within one particle. An alternative method to obtain bimetallic nanoparticles is also suggested using a spontaneous electrochemical process from salt solutions. BMNP for both Al-Cu and Al-Ni have been prepared and studied.The oxidation, ignition and thermal reactivity of the BMNP of Al-Cu and Al-Ni in a simultaneous thermogravimetric (TG) and differential scanning calorimetry (DSC) experiments have been carried out. The microstructure has been characterized with a scanning electron microscope (SEM) and transmission electron microscope (TEM). The phase compositions of the reaction products have been investigated with X-ray diffraction.By comparing the peak temperature of the first exothermic reaction in DSC and the phase transition temperatures in the respective binary systems, it has been found that for Al-Cu BMNP the melting of an alloy played a pivotal role for the early ignition reaction. The comparison of the reactivity of BMNP with that of aluminum nanoparticles has shown a greater reactivity of BMNP Al-Cu and Al-Ni.

Phase stability in nanoscale material systems: extension from bulk phase diagrams

Phase diagrams of multi-component systems are critical for the development and engineering of material alloys for all technological applications. At nano dimensions, surfaces (and interfaces) play a significant role in changing equilibrium thermodynamics and phase stability. In this work, it is shown that these surfaces at small dimensions affect the relative equilibrium thermodynamics of the different phases. The CALPHAD approach for material surfaces (also termed "nano-CALPHAD") is employed to investigate these changes in three binary systems by calculating their phase diagrams at nano dimensions and comparing them with their bulk counterparts. The surface energy contribution, which is the dominant factor in causing these changes, is evaluated using the spherical particle approximation. It is first validated with the Au-Si system for which experimental data on phase stability of spherical nano-sized particles is available, and then extended to calculate phase diagrams of similarly sized particles of Ge-Si and Al-Cu. Additionally, the surface energies of the associated compounds are calculated using DFT, and integrated into the thermodynamic model of the respective binary systems. In this work we found changes in miscibilities, reaction compositions of about 5 at%, and solubility temperatures ranging from 100-200 K for particles of sizes 5 nm, indicating the importance of phase equilibrium analysis at nano dimensions.

Phase stabilities at a glance II: Ternary ordering variants of pyrite and marcasite type structures

There is a solid history of theoretical and experimental studies of pyrite- and marcasite-like systems that primarily occur for dipnictide and disulfide systems of late transition metals. Ordered mixed occupation of the anionic sites of these compounds results in a multitude of different ternary structures. A full set of possible combinations is presented here including all experimentally known structure prototypes. They are part of a series MPnS (M=Fe, Co, Ni; Pn=As, Sb) that is investigated in terms of recently established stability diagrams with decomposition lines. In contrast to the respective binary systems, significantly lower differences in cohesive energies and cell volumes have to be dealt with particularly for related ordering variants. Due to sufficient experimental data on hand, the accuracy of the GGA-based density functional theory calculations can be estimated within the marginal ranges in order to allow for reliable predictions of new phases of these and many other related systems.

Interplay between Metal⋅⋅⋅π Interactions and Hydrogen Bonds: Some Unusual Synergetic Effects of Coinage Metals and Substituents

The ternary systems of C(2)H(4) (C(2)H(2) or C(6)H(6))-MCN-HF (M=Cu, Ag, Au) and the respective binary systems were investigated to study the interplay between metal⋅⋅⋅π interactions and hydrogen bonds. The metal⋅⋅⋅π interactions in C(2)H(4)-MCN become stronger with the irregular order Ag<Cu<Au, while the hydrogen bonds in MCN-HF become weaker following the same order. The metal⋅⋅⋅π interactions are weakened as the H atoms in the π system are replaced with electron-withdrawing groups and enhanced by electron-donating groups. Type 1 of these ternary systems, in which MCN acts as Lewis base and acid simultaneously, is more stable than type 2, in which C(2)H(4) acts as a double Lewis base. Negative cooperativity is present in type 2 ternary systems with a weakening of the metal⋅⋅⋅π interactions and the hydrogen bonds. Positive cooperativity is found in type 1 ternary systems with an enhancement of the metal⋅⋅⋅π interactions and the hydrogen bonds, except for C(2)(CN)(4)-AuCN-HF-1. The weaker metal⋅⋅⋅π interaction in C(6)H(6)-AuCN has a greater enhancing effect on the hydrogen bond in AuCN-HF than those in C(2)H(4)-AuCN and C(2)H(2)-AuCN. These synergetic effects were analyzed with the natural bond orbital and energy decomposition.

Investigation into the synergistic effects in ternary cementitious systems containing portland cement, fly ash and silica fume

Abstract This research was primarily conducted to verify the presence of synergistic effects in ternary cementitious systems containing portland cement (OPC), class C fly ash (FA) and silica fume (SF). A subsequent objective of the study was to quantify the magnitude of the synergy and to determine its source. For a ternary mixture containing 20% FA and 5% SF by mass, the synergistic effect was observed mostly at later ages (7 days onward) and it resulted in an increased compressive strength and resistance to chloride ion penetration as well as a reduced rate of water absorption (sorptivity) compared to predictions based on individual effects of FA and SF in respective binary systems. The observed synergy was attributed to both chemical and physical effects. The chemical effect manifested itself in the form of an increased amount of hydration products. The physical effect associated with packing density was, somewhat contrary to general belief, not due to an optimized particle size distribution of the binder components of the ternary cementitious system. Instead, it was the result of smaller initial inter-particle spacing caused by lower specific gravities of both FA and SF which, in turn, led to a lower volumetric w/cm. If the mixture design was adjusted to account for these differences, the physical effect would be diminished.

Liquidus determination in the Cu–Sb–Sn ternary system

In this study the liquidus temperature in the ternary Cu–Sb–Sn system was determined by using DTA/DSC experimental technique. Experiments were carried out along three sections of the ternary system assuming x Cu = 0.8; x Cu/ x Sn = 1.22 and x Sb/ x Sn = 1, respectively. The liquidus temperatures obtained in this study were compared with calculated liquidus lines. Muggianu approximation method was used to predict respective isopleths along chosen cross-sections. It was found that measured liquidus temperatures are lower than those calculated from respective binary systems using CALPHAD formalism.

Effect of K+ on Na - Ca exchange and the SAR-ESP relationship

In Australia, application of winery wastewater to land is increasingly being viewed as the most environmentally sound and cost-effective means of disposal. This wastewater contains high concentrations of both sodium (Na+) and potassium (K+), which have the potential to accumulate in the profile of irrigated soils and adversely alter physical properties such as aggregate stability and hydraulic conductivity. Cation exchange equilibria in soil of mixed illite and kaolinite mineralogy have been investigated in binary Ca–Na and Ca–K systems and in a ternary Ca–Na–K system. In the respective binary systems, resulting exchangeable potassium percentage was nearly twice the corresponding exchangeable sodium percentage (ESP), indicating a high binding affinity of K+ in this soil. In a ternary system, soils were equilibrated with solutions of differing sodium adsorption ratio (SAR) and potassium adsorption ratio (PAR) within ranges typical of winery wastewater. The presence of K+ had a significant effect on the relationship between SAR and ESP, whereby ESP decreased with increasing PAR. Resulting ESP in the ternary system was consistently lower than in the binary system. Cation selectivity between solid and solution phases in the ternary system was calculated from the Vanselow and K-selectivity coefficients and showed a decreasing selectivity for Na+ with increasing K+ in solution. It is expected that, due to the high K+ content of winery wastewater (i.e. &gt;400 mg/L), adsorption of Na+, and subsequent ESP, will be less than in wastewaters of comparable Na+ concentration yet absent K+.

Effect of menthol as solid cosolvent on the solubility enhancement of clozapine and lamorigine in supercritical CO 2

The solubilities of mixed clozapine and menthol also lamotrigine and menthol in supercritical carbon dioxide were determined at 313 and 323 K and over pressure ranging from 123 to 337 bar. The solubility of both solutes with solid cosolvent system is observed to increase relative to the value of the corresponding without solid cosolvent system. As compared with their respective binary system (without solid cosolvent), the mixed clozapine (with solid cosolvent) solubility enhancement greatly by around 56 times and the lamotrigine one does by approximately eight times. In presence of menthol these chemicals have solubilities with values ranging from 1.88 × 10 −4 to 4.48 × 10 −4 (clozapine) and 0.09 × 10 −4 to 0.36 × 10 −4 (lamotrigine) mole fraction. The solubility data were correlated using five semi-empirical density-based models (Chrastil, Bartle, K–J, M–T and Thakur models). Correlated results for clozapine with the Chrastil, M–T, K–J, and Bartle models and for lamotrigine with the Chrastil, M–T and Bartel models are in excellent agreement with the experimental data.

The solubility of water in mixtures of dimethyl ether and carbon dioxide

This paper reports measurements of the solubility of water in liquid and supercritical fluid mixtures of dimethyl ether and carbon dioxide. The measurements were made by extracting water under saturation conditions using premixed liquid dimethyl ether–carbon dioxide mixtures. Results are reported for temperatures of 313.8 K and 333.3 K at 9.0 MPa and 15.0 MPa. Results are fitted to the Peng–Robinson cubic equation of state with mixing rules according to Wong and Sandler, using binary interaction parameters fitted to the literature data for the respective binary systems: dimethyl ether–water; dimethyl ether–carbon dioxide; and carbon dioxide–water. Liquid densities for dimethyl ether–carbon dioxide mixtures, measured using a coriolis flow instrument, are also reported.

Liquid Crystalline Systems of Phytantriol and Glyceryl Monooleate Containing a Hydrophilic Protein: Characterisation, Swelling and Release Kinetics

Swelling and phase behaviour of phytantriol and glyceryl monooleate (GMO) matrices with varying water loadings were investigated. Release of a model protein, FITC-Ova was subsequently examined. Polarised light microscopy and small angle X-ray scattering analysis showed that the addition of FITC-Ova only altered the liquid crystalline structure of phytantriol matrices at low water loadings, and that postrelease study, the phase structure of matrices at both low and high loading reflected that of the binary system. Addition of FITC-Ova to GMO matrices also altered the liquid crystalline structure when compared to the respective binary system at low but not at high loading. All samples analysed after the release study had transformed to the reverse hexagonal phase (HII). Swelling studies revealed a faster and more extensive swelling of GMO when compared to phytantriol. Release of FITC-Ova from phytantriol matrices was faster and occurred to a greater extent most likely due to the conversion of GMO matrices into the HII phase. No effect on release as a function of initial water content was observed for either lipid. We have confirmed that phytantriol based liquid crystalline matrices can sustain the release of a hydrophilic protein, suggesting its suitability as a potential sustained antigen-delivery system. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:4191–4204, 2009

Kinematic Viscosity of Aqueous Solutions of Ethanol and Glucose in the Range of Temperatures from 20 to 45°C

The purpose of this investigation was to determine, using a capillary viscosimeter, kinematic viscosity data of aqueous solutions of ethanol and glucose, at several temperatures (from 20 up to 45ºC) and concentrations. Glucose solubility strongly depended on ethanol concentration allowing the kinematic viscosity study (from 5% up to 45% w/w ethanol concentration with variable glucose concentrations as a function of its solubility). Kinematic viscosity modelling with solution concentration and temperature simultaneously, based on previous models for respective binary systems, was successfully carried out. The estimated values by this model give low average deviations (2.62%) from the experimental data. Glucose solubility (at 25ºC) in alcohol solutions and index of refraction (at 20ºC) of ternary solutions were also determined and empirical models are proposed in order to evaluate both physical properties with high (R2 > 0.993 and > 0.991, respectively) accuracy.