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The reaction products formed in the SO2 – ROH – (HOCH2)3CNH2 (where R – CH3, C2H5, n-C3H7, i-C3H7, n-C4H9 and n-C5H11) systems were isolated and identified as: binary salt – ammonium O-methylsulfite [(HOCH2)3CNH3]+ [CH3OSO2]− (1); 1/1 charge transfer complex between diethyl sulfite (2) and tris(hydroxymethyl)aminomethane by S-N binding; polymorhps of zwitterionic internal salt – O-sulfite tris(hydroxymethyl)methylammonium (at R – n-C4H9 and n-C5H11); and its solvates with n-propanol 1/1 (3) and isopropanol 2/1. The structures of all synthesized products were confirmed by FT-IR, Raman, 1H NMR and 13C NMR spectrometry, and the structure of 1 and 3 was characterized by crystal X-ray diffraction studies as well. [ABSTRACT FROM AUTHOR]

Reducing carbon emissions has emerged as a critical challenge, and among various methods, solvent-based CO2 capture technology is the most widely employed. Amines, particularly effective solvents for CO2 capture, play a significant role in this process. To advance this technology, it is essential to understand the thermodynamic properties of the interactions between the constituent components. In this study, we examined the deviation in dynamic viscosity ( Δ η ), and the deviation in refractive index ( Δ n D ) calculated from the measured η and n D data for n-butylamine (NBA) with alkanol systems. The temperature range for our study was 298.15–318.15 K. We utilized the Ab-initio approach for Δ η data analysis. Our findings revealed that the depolymerization power of alkanol is dependent on the unlike interactions. Furthermore, we employed various correlations/mixing rules to predict the η as well as n D values from the experimental pure components data. The standard deviation was utilized to express the predictive abilities of these correlations. [ABSTRACT FROM AUTHOR]

As N-isopropyl-2-propanamine+alkanol (C1-C3) systems are potential absorbents for CO2 capture, we measured density (ρ), viscosity (η) and the ultrasonic speed data (u) for N-isopropyl-2-propanamine (DIPA) with alkanol (C1-C3) at T=(298.15 and 308.15) K and 0.1 MPa. The experimental density (ρ), viscosity (η) and ultrasonic speed (u) data were used to derive excess molar volume (VmE), apparent, partial, and excess partial molar volume, deviation in viscosity and deviation in ultrasonic speed, excess isentropic compressibility ( κ s E ). We predicted the VmE values using the Prigogine-Flory-Patterson theory (PFP) and by Nakata and Sakurai model. An Ab initio approach was proposed for the excess isentropic compressibility (κ s E) and Δη data which not only reproduces the experimental data but also gives important parameters that describe the extent of depolymerization on mixing and strength of intermolecular interactions. [ABSTRACT FROM AUTHOR]

Signal transduction by the high-affinity IgE receptor (FcεRI) depends on membrane lipid and protein compartmentalization. Recently published data show that cells treated with 1-heptanol, a cell membrane fluidizer, exhibit changes in membrane properties. However, the functional consequences of 1-heptanol-induced changes on mast cell signaling are unknown. This study shows that short-term exposure to 1-heptanol reduces membrane thermal stability and dysregulates mast cell signaling at multiple levels. Cells treated with 1-heptanol exhibited increased lateral mobility and decreased internalization of the FcεRI. However, this did not affect the initial phosphorylation of the FcεRI-β chain and components of the SYK/LAT1/PLCγ1 signaling pathway after antigen activation. In contrast, 1-heptanol inhibited SAPK/JNK phosphorylation and effector functions such as calcium response, degranulation, and cytokine production. Membrane hyperfluidization induced a heat shock-like response via increased expression of the heat shock protein 70, increased lateral diffusion of ORAI1-mCherry, and unsatisfactory performance of STIM1-ORAI1 coupling, as determined by flow-FRET. Furthermore, 1-heptanol inhibited the antigen-induced production of reactive oxygen species and potentiated stress-induced plasma membrane permeability by interfering with heat shock protein 70 activity. The combined data suggest that 1-heptanol-mediated membrane fluidization does not interfere with the earliest biochemical steps of FcεRI signaling, such as phosphorylation of the FcεRI-β chain and components of the SYK/LAT/PLCγ1 signaling pathway, instead inhibiting the FcεRI internalization and mast cell effector functions, including degranulation and cytokine production. [ABSTRACT FROM AUTHOR]

Experimental thermodynamic and spectroscopic investigations on binary liquid mixtures containing tri-n-butylamine with 2-propanol, 2-butanol and 2-pentanol have been discussed in this article. The aforesaid binary mixtures have been examined over the entire range of composition at a temperature range of 293.15–308.15 K with a temperature step of 5 K and at 0.1 MPa pressure. To explore the mixtures thermodynamically, the density ( ρ) and speed of sound (u) at various compositions and temperatures have been measured. Experimental values of these two properties have been used to find out various thermodynamic parameters, viz., excess molar volumes ( V m E ), excess isentropic compressibilities ( κ s E ), apparent molar volumes ( V φ ), partial molar volumes ( V ˉ m ), excess partial molar volumes ( V ˉ m E ) and partial molar volumes at infinite dilution ( V ˉ m E , ∞ ). These parameters are analysed in terms of form and degree of unlike interactions. Along with this, these parameters are also examined to figure out the effect of chain length and temperature on interactions. Further, the computed excess parameters have also been correlated with the compositions using the Redlich–Kister-type polynomial. Similar to excess parameters, the density and speed of sound have also been correlated to compositions using the Jouyban–Acree model. Apart from this, the mixtures were also analysed using FTIR spectroscopy studies. [ABSTRACT FROM AUTHOR]

[Display omitted] • The density, and viscosity data of HBM + alkanol (C 3 -C 4) is reported. • Partial, excess partial and apparent molar volume were also calculated. • Graph theoretical approach was used to predict the V m E and Δ η values. • FT-IR analysis and Molecular Dynamic Simulation were also performed. • The η data were analyzed by using various correlations. This study investigates the density (ρ) and viscosity (η) of a binary mixture of methyl 2-hydroxyisobutyrate (HBM) with alkanol such as isomers of propanol and n–butanol at pressure 0.1 MPa and at T = 288.15 K–323.15 K. The excess molar volume (V m E) , and deviation in viscosity (Δ η) for the binary mixtures were calculated by experimentally measured ρ and η data at all temperatures. The V m E and Δ η values exhibited a negative trend for HBM and alkanol systems and to become increasingly negative as temperature increased. For all the systems, minima occur at about (x 1 ≃ 0.40 - 0.50) of HBM. The excess properties were associated with the RK polynomial equation. To examine the intermolecular interactions between the binary (1 + 2) mixtures, the V m E and viscosity data were analyzed using a graph theoretical approach (GTA), molecular dynamics (MD) simulations and numerous correlations. Moreover, the excess free energy of activation (Δ G ∗ E ) was computed utilizing η data. Additionally, FT–IR spectroscopy supported the development of H-bonding between the constituents' molecules. [ABSTRACT FROM AUTHOR]

One new alkanol, 2,4,5‐heptanetriol(1), together with four compounds, 6‐heptene‐2,4,5‐triol (2), rel‐(1S, 4S, 5R, 7R, 10R)‐10‐desmethyl‐1‐methyl‐11‐eudesmene (3), 2,3‐dihydro‐5‐hydroxy‐2‐methyl‐4H‐1‐benzopyran‐4‐one (4), (−)‐regiolone (5) were isolated from the ethyl acetate extract of rice solid‐substrate cultures of endolichenic fungus Daldinia childiae for the first time. Compounds 1, 2, and 3 were separated firstly from the genus Daldinia. Their structures were elucidated by spectral data and compound 3 exhibited α‐amylase inhibitory activity. [ABSTRACT FROM AUTHOR]

Hexafluoroisopropanol-alkanol (C 6 –C 12) supramolecular solvents were proposed and their application potential as restricted access extraction solvents was assessed. Hexafluoroisopropanol acts as alkanol reverse micelle-forming agent and density-regulating agent for the supramolecular solvent synthesis. The formation of supramolecular solvent only needs a small percentage of hexafluoroisopropanol (<10% v/v for alkanol <5% v/v) and is almost not affected by the pH (2-11) and low ionic strength (NaCl <3%, w/v) of aqueous medium. The supramolecular solvents have higher density than water and consist of reversed micellar aggregates with irregular mesh structures and hydrophilic inner cavities, and the hydrophilic cavity size is obviously dependent on the hexafluoroisopropanol amount in the bulk system but almost not relevant to the alkanol amount. The hydrogen-bond and hydrophobic interactions of hexafluoroisopropanol with alkanol and the hydrogen-bond force between hexafluoroisopropanol and water play crucial roles in the formation of supramolecular solvent. The supramolecular solvents not only do not or slightly dissolve macromolecules (proteins, polysaccharides, and humic acid sodium), but also can effectively exclude them in extraction procedure; meanwhile, they can extract small molecules from complex samples with high extraction rate (even near 100% through optimization). The extraction mechanism involves the hydrophilic inner cavity size of supramolecular aggregates and the interactions (hydrogen-bond, hydrophobic) between supramolecular solvent and analytes. The suitability of supramolecular solvents as extractants was evaluated by extracting and determining chlorophenols in real water samples, coupled with high performance liquid chromatography-ultraviolet detector. The enrichment factors of 72–147 were obtained. Limits of detection were from 0.38 to 0.57 ng mL−1. The recoveries ranged from 96.0 to 107.9%, and intra-day and inter-day precisions were less than 4.0%. The novel hexafluoroisopropanol-alkanol supramolecular solvents have promising potential as restricted access extractants. Image 1 • A new type of hexafluoroisopropanol-alkanol supramolecular solvent was proposed. • A small amount of hexafluoroisopropanol was needed to form supramolecular solvent. • High density supramolecular solvent is easily collected even at microvolume. • Supramolecular solvent consists of reverse micelle aggregates with mesh structure. • Supramolecular solvent has promising potential as a restricted access extractant. [ABSTRACT FROM AUTHOR]

Sugarcane smut caused by the basidiomycetes fungus Sporisorium scitamineum is a devastating disease for the sugarcane industry worldwide. As the initial step, the smut teliospores germinate on sugarcane buds, and subsequently, the mycelium infects the bud tissues. However, chemical signals that induce spore germination are still unknown. By comparison of the behavior of the teliospores on the buds of both resistant and susceptible varieties, we found that spore germination rates were significantly lower on the buds of resistant cultivars ZZ1, ZZ6, and ZZ9 than on the susceptible varieties GT42 and ROC22. It was found that the levels of hexacosanol and octacosanol were higher on the buds of smut-susceptible varieties than on the smut-resistant varieties. These observations were extended to the smut-resistant and smut-susceptible sub-genetic populations derived from the cross of ROC25 and YZ89-7. In artificial surface assays, we found that hexacosanol and octacosanol promoted smut teliospore germination. Transcriptome analysis of smut teliospores under the induction by octacosanol revealed that genes in the MAPK signaling pathway and fatty acid metabolism were significantly differentially expressed. Overall, our results provide evidence that alkanol plays important roles in smut teliospore germination and thus could be used as a potential marker for smut resistance in sugarcane breeding programs.

In this study, the viscosity behavior of two mixtures of Ethaline (1 ChCl:2 ethylene glycol) with either methanol or ethanol were investigated over the temperature range of 283.15–333.15 K at atmospheric pressure. The measured viscosities of neat Ethaline, methanol, and ethanol showed reliable agreement with the corresponding reported literature values. The mixture viscosities were modeled by an Arrhenius-like model to determine the behavior of viscosity with respect to temperature. The data were also modeled by the four well-known mixture viscosity models of Grunberg–Nissan, Jouyban–Acree, McAllister, and Preferential Solvation. All of the model results were reliable, with the Jouyban–Acree and Preferential Solvation models showing the most accurate agreement with the experimental measurements. The Jones–Dole viscosity model was also investigated for the measured viscosities, and by analyzing the results of this model, strong interactions among Ethaline and the alcohol molecules were proposed for both systems. As a final analysis, viscosity deviations of the investigated systems were calculated to study the deviations of the viscosity behaviors with respect to ideal behavior. Both systems showed negative viscosity deviations at all of the investigated temperatures, with the negative values tending towards zero, and hence more ideal behavior, with increasing temperatures. Moreover, in order to correlate the calculated viscosity deviations, the Redlich–Kister model was successfully used for both systems and at each investigated temperature.

Graphical abstract Highlights • Langmuir's principle of independent surface action is combined with ANN-structure to form a new model. • The model fits 6 alkanols collectively and obtains the adsorption constant K. • ln K is linearly correlated to the alkyl length. • The correlation captures the net interaction between surface water and hydrophobic/hydrophilic hydration shells. Abstract A new model, inspired by Langmuir's classical "principle of independent surface action" and an artificial neural network algorithm, was developed to predict the surface tension of water/alkanols. The model was applied collectively to experimental data of six 1-alkanols, from ethanol to 1-heptanol. From the modelling results, the surface action of each component in alkanol molecules was determined. More importantly, the model was able to reveal the relationship between the alkanols length and the adsorption constant, K. The relationship was similar to other universal rules of surfactants: ln K is linearly correlated to the alkyl length. The structure-based model provides an important framework to describe the equilibrium between the aqueous phase and the interfacial zone. The new insights can be combined with molecular simulations to describe the molecular arrangement within the interfacial zone. After Langmuir's attempt almost a century ago, a structure-based surface model was successfully obtained. [ABSTRACT FROM AUTHOR]

Deep Eutectic Solvents (DESs) have been introduced recently as a new generation of green solvents. DESs have great potential to be used in different fields and applications, and so, it is important to have information on the properties of DESs and their mixtures. Up to now, the volumetric properties of only aqueous mixtures of DESs have been investigated. In this study, we measured the densities of pseudo-binary mixtures of methanol and choline chloride + urea (1:2) (reline) at atmospheric pressure over the temperature range of 293.15–323.15 K. Based on the measured density data, excess molar volumes of the mixtures were calculated. All of the excess molar volumes had negative values, which show the stronger solvation interactions of the mixture molecules compared to the interactions within pure reline or methanol. Furthermore, the volumetric properties of partial molar volume, excess partial molar volume, partial molar volume at infinite dilution, excess partial molar volume at infinite dilution, and isobaric volume expansion were calculated. By comparing the excess partial molar volumes at infinite dilution of reline and methanol, it is concluded that each prefers to be surrounded by the other, and this tendency is stronger for reline molecules. [ABSTRACT FROM AUTHOR]

The surface hydrophobicity of starch-based films could be regulated using a two-step surface modification method. Such modification was realized by grafting with alkanols of different chain lengths (hexanol, dodecanol and octadecanol) on the surface of starch-based films. The grafting of alkanol increased the mobility of glycerol as the plasticizer within the film surface. Also, this grafting increased the mass ratio of carbon to oxygen on the film surface but reduced the mass ratio of carbon to nitrogen. Under the same reaction conditions, there were fewer dodecyl chains grafted onto the film surface than hexyl or octadecyl chains. Furthermore, the results revealed that the surface hydrophobicity of starch-based films could be enhanced by simply increasing the alkyl chain length. Also, fewer alkyl chains tended to reduce the surface hydrophobicity of the films. These results are valuable for the rational design of starch-based materials with demanded hydrophobic properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • The density, ultrasonic speed, and viscosity data of p -chlorotoluene + alkanol (C 1 -C 2) is reported. • The excess properties data are correlated with the Redlich-Kister polynomial. • Partial and excess partial molar volume were also calculated. • The Δ u values interpretted using FLT and CFT. • Ab-initio approach applied to predict the Δ η and κ s E data. The measurement of density (ρ), viscosity (η) and ultrasonic speed (u) have been conducted at T = 298.15 K–318.15 K and at 0.1 MPa to study the intermolecular interactions between p –chlorotoluene with alkanol (C 1 –C 2). These data were utilized to derive the excess properties like excess molar volume (V m E), deviation in viscosity (Δ η), excess free energy of activation (ΔG*E), deviation in ultrasonic speed (Δ u), and excess isentropic compressibility (κ s E) for binary mixtures. Utilizing the V m E values, partial molar volume and excess partial molar volume were calculated. The Δ η and κ s E were investigated using theoretical models such as the Singh model and ab initio approach, which yielded interactional parameters that not only indicate the extent of unlike interactions and depolymerization of self–associated alkanol but also predicts the Δ η and κ s E for these systems. The conclusions of the ab initio approach were further validated by the Singh model for viscosity. The u data were further interpreted by various correlations and theories. Regarding correlation, Nomoto's correlation demonstrated high predictive power for ultrasonic speed data, respectively, compared to other correlations. The resulting excess properties were fitted to Redlich–Kister polynomial equations. The V m E values were observed to be negative for p –chlorotoluene + alkanol systems at all temperatures. The study of the binary mixtures is significant because it sheds light on the nature of intermolecular interactions which has practical implications in areas such as chemical synthesis, solvent selection, and understanding the effects of solvents on reaction rates and product yields. [ABSTRACT FROM AUTHOR]

New experimental data of mixing properties ( v E and h E ), measured at 298.15 K and atmospheric pressure, are presented for a set of binaries formed by alkyl (methyl to pentyl) methanoates with the first four alkanols (methanol to butanol). The experimental data are represented adequately with a polynomial equation that permits a more detailed analysis of the structural behaviour of the solutions formed. The numerical values of v E and h E are the net result of several effects (positive and negative) due to inter- and/or intramolecular interactions explained by FTIR/ATR spectroscopy, which affect the modelling used. In a predictive context, two versions of the UNIFAC group contribution model were used, introducing in one of them the specificities of the associative effects, both for the methanoates and the alkanols. In both versions, it was necessary to recalculate OH/HCOO interaction parameters, which finally produced acceptable values of h E . To estimate the volumetric and energetic behaviour together, a combined model, EOS/ g E , constituted by Soave-Redlich-Kwong/UNIFAC, was used and the results obtained are acceptable. [ABSTRACT FROM AUTHOR]

The main aim of this work is to study the interface of dimethylsulfoxide + n -alkanol mixtures. To achieve this aim, first, the surface tension of (dimethylsulfoxide + methanol, ethanol, and propanol) was measured as a function of mole fraction and temperature. These measurements were conducted in the temperature range of (293.15–308.15) K and atmospheric pressure. Then the surface tensions of binary mixtures were correlated by Shereshefsky model and excellent results were obtained. The average percent deviation in correlation of surface tension of studied mixtures was 0.7%. Based on Shereshefsky model, the standard Gibbs energy of adsorption and the free energy change in the surface region were calculated. The free energy change was used to obtain the excess number of molecular layers in the surface region. Additionally, the extended Langmuir model was applied. The required parameters of the model were adjusted, the standard Gibbs energy of adsorption was calculated, and positive or negative deviations from ideality were determined. Also surface compositions were calculated by using extended Langmuir model. In addition to these two methods, a predictive model based on the equality of the chemical potential of species in the interface and bulk liquid was used to predict surface compositions and surface tension of mixtures. Additionally, by using surface tensions of studied mixtures at different temperaturs, specific surface enthalpy and specific surface entropy were calculated for (dimethylsulfoxide + n -alkanol) mixtures. [ABSTRACT FROM AUTHOR]

Primordial enzymes are proposed to possess broad specificities. Through divergence and evolution, enzymes have been refined to exhibit specificity towards one reaction or substrate, and are thus commonly assumed as “specialists”. However, some enzymes are “generalists” that catalyze a range of substrates and reactions. This property has been defined as enzyme promiscuity and is of great importance for the evolution of new functions. The promiscuities of two enzymes, namely glycerol dehydratase and diol dehydratase, were herein exploited for catalyzing long-chain polyols, including 1,2-butanediol, 1,2,4-butanetriol, erythritol, 1,2-pentanediol, 1,2,5-pentanetriol, and 1,2,6-hexanetriol. The specific activities required for catalyzing these six long-chain polyols were studied via in vitro enzyme assays, and the catalytic efficiencies were increased through protein engineering. The promiscuous functions were subsequently applied in vivo to establish 1,4-butanediol pathways from lignocellulose derived compounds, including xylose and erythritol. In addition, a pathway for 1-pentanol production from 1,2-pentanediol was also constructed. The results suggest that exploiting enzyme promiscuity is promising for exploring new catalysts, which would expand the repertoire of genetic elements available to synthetic biology and may provide a starting point for designing and engineering novel pathways for valuable chemicals. [ABSTRACT FROM AUTHOR]

• The viscosity and ultrasonic speed data of AMP + alkanol (C 1 -C 3) reported. • The excess properties data were correlated with Redlich-Kister polynomial. • The excess isentropic compressibility and intermolecular free length were also calculated. • An Ab initio approach for viscosity was proposed for binary associated mixtures. • Viscosity data predicted by using various models/correlation. We report the experimental data of dynamic viscosity (η) and ultrasonic speed (u) for 2-amino-2-methylpropan-1-ol (AMP) (1) + alkanol (C 1 -C 3) (2) at T = (298.15–318.15) K and 0.1 MPa pressure. The derived excess (or deviation in) properties like dynamic viscosity (Δ η), speed of sound (Δ u) and excess isentropic compressibility (κ S E) were regressed through Redlich-Kister polynomial equation. The Δ η values were analyzed in terms of an Ab-initio approach, to study the intermolecular interactions between the binary components. Our analysis indicated that compared to propanol, methanol and ethanol interact strongly with AMP and 2-propanol exhibited the weakest interactions with AMP owing to steric hindrance by branched propyl group. In addition, viscosity (η) values and ultrasonic speed (u) data were analyzed using the various thermodynamic models/correlations that agreed well with our experimental data. Furthermore, we analyzed the FT-IR spectra of pure components and their binaries and observed prevailing hydrogen bonding interactions between the N-atom and OH-group of AMP with the OH-group of alkanol. Our findings highlight the great bonding capability of AMP with lower alkanol due to its small size and linear shape and can provide information on designing effective binary mixtures (blended) solvents based on AMP for CO 2 absorption. [ABSTRACT FROM AUTHOR]

Liquid-vapor phase equilibria in dimethyl sulfoxide-alkanol (1-propanol, 1-butanol, and tert-butanol) binary systems are studied using a static method. The total saturated vapor pressure in the temperature range of 293.15-323.15 K is measured. The partial pressures of dimethyl sulfoxide and alkanes have been calculated via integrating the Gibbs-Duhem equation. Excess molar Gibbs energies are described by the Redlich-Kister equation, and the correlation parameters are calculated. The nature of the deviation from the ideal behavior of these solutions is explained by allowing for the presence of competing homo- and heteromolecular interactions and the considerable effect of the length of the alkanols' hydrocarbon chains has on the values of the thermodynamic parameters. [ABSTRACT FROM AUTHOR]

Self-diffusion of methanol, ethanol, 1-propanol and 2-propanol has been studied by molecular dynamics simulation in the temperature range between the melting pressure curve and 478 K at pressures up to 300 MPa. The simulation results on self-diffusion of methanol, ethanol and 2-propanol (for 2-propanol, at high temperatures) agree well with experiment, which suggests that the simulation method is a powerful tool to obtain self-diffusion coefficients over wide range of temperature and pressure, under which it is rather difficult for experiments. The local structures of methanol, ethanol and 2-propanol are investigated by calculating the radial distribution functions, H-bond numbers, coordination numbers and the ratios of H-bond number divided by coordination number. The correlation between self-diffusion and structural properties, and the influence of temperature and pressure on them are discussed. The degree of forming H-bond space network in methanol, ethanol and water is higher than that in 2-propanol, and they are all higher than those in ammonia and methylamine. The simulation results demonstrate that the effect of hydrogen bonding on the translational dynamics in methanol and ethanol is more pronounced than that in 2-propanol. [ABSTRACT FROM PUBLISHER]

Surface tension for seven binary mixtures containing a pyridinium-based ionic liquid (1-propylpyridinium tetrafluoroborate, 1-butylpyridinium tetrafluoroborate, 1-butyl-3-methylpyridinium tetrafluoroborate, or 1-butyl-4-methylpyridinium) and a short chain alkanol (methanol or ethanol) were determined at the temperatures: (293.15, 303.15, 313.15, and 323.15) K. From these data, the surface tension deviations were calculated. These deviations were correlated using a Redlich-Kister polynomial expansion. Moreover, relative adsorptions of alkanol at the (air + liquid) interface were calculated from the Gibbs isotherm. [ABSTRACT FROM AUTHOR]

High pressure–temperature isopleths were obtained, experimentally, for the binary system of methanol + ethylene within a temperature and pressure range of 293–373 K and 38–119 bar, respectively. The experimental results were modeled using the Cubic-Plus-Association (CPA), Peng–Robinson (PR) and Soave–Redlich–Kwong (SRK) equations of state. The ability of the CPA model to predict the phase behavior of methanol + ethylene is much better than the SRK and PR models. However, even though the p–T diagrams indicate that the CPA equation of state correlates well with the experimental results, by increasing ethylene concentrations, the errors of CPA increase due to the solvation that occurs in methanol + ethylene systems. In this work, the effect of solvation is also investigated. Results show that deviations from experimental data are less for CPA with solvation than for the CPA without solvation. Correlations are presented for the binary interaction (kij) and the association volume (βAiBj) parameters to model the phase behavior of methanol + ethylene, as both of these parameters were indicated to be temperature-dependent. [ABSTRACT FROM AUTHOR]

Highlights: [•] The study reports density and ultrasonic velocity data of 2-(dimethylamino)ethanol+methanol/ethanol mixtures. [•] To elucidate the interactions in 2-(dimethylamino)ethanol+methanol/ethanol binary mixtures. [•] Provides information on nature and relative strength of interactions in these mixtures. [•] Correlates physicochemical properties with interactions in these mixtures. [ABSTRACT FROM AUTHOR]

Highlights: [•] Refractive indices of a pyridinium ionic liquid with an alkanol have been reported. [•] From measured data excess refractive indices have been obtained and correlated. [•] Excess refractive indices and excess volumes of the mixtures have been related. [•] Mixing rules have been used to predict the refractive indices of the mixtures. [Copyright &y& Elsevier]

Abstract: Densities and speeds of sound have been determined for the binary mixtures containing an ionic liquid (1-butyl-3-methylpyridinium tetrafluoroborate or 1-butyl-4-methylpyridinium tetrafluoroborate) and an alkanol (methanol or ethanol) over the temperature range (293.15 to 323.15)K. Excess volumes and excess isentropic compressibilities have been calculated from density and speed of sound data and correlated. All the mixtures show negative values for these excess properties. Furthermore, the isothermal (vapour+liquid) equilibrium has been measured at T =(303.15 and 323.15)K, and the corresponding activity coefficients and excess Gibbs functions have been obtained. In this case, positive excess Gibbs functions have been found. We have carried out an exhaustive interpretation of the experimental results in terms of structural and energetic effects taking also into account the thermodynamic information of pure compounds. Finally, in order to study the influence of both, the presence and the position of methyl group in the cation, we have compared the results of these systems with those obtained for the mixtures formed by 1-butylpyridinium tetrafluoroborate and methanol or ethanol. [Copyright &y& Elsevier]

Abstract: Calorimetric measurements were performed for six binary mixtures of isoamyl acetate+alcohols (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol and 2-butanol) by a Parr 1455 solution calorimeter over the entire composition range at T =298.15K and atmospheric pressure. The results were applied to calculate excess molar enthalpies and excess partial molar enthalpies . The values were positive over the whole of composition range and become more positive with increasing the chain length and steric hindrance of the alkanols. The trend of the data was interpreted in terms of the self-association of pure alkanols, dipole–dipole interactions between ester molecules and cross-association between unlike molecules (ester–alkanol). The correlations of experimental data were performed by Redlich–Kister equation and NRTL and UNIQUAC models. [Copyright &y& Elsevier]

The conductivity (σ) measurement was carried out on water/dioctyl sulfosuccinate sodium salt (DOSS)/heptanol (decanol)/toluene reverse microemulsions. Addition of toluene was distinctly observed to inhibit the conductance percolation of water/DOSS/decanol/toluene systems. The effect of additives (sodium chloride, sodium salicylate and sodium cholate) with various concentrations on the conductivity behavior of water/DOSS/heptanol (decanol)/toluene systems was also investigated and discussed. The conductivity of a water/DOSS/heptanol/toluene system was almost unchanged in the concentration ranges of sodium chloride and sodium salicylate studied, while it decreased with the increase in the sodium cholate concentration. The conductance of the water/DOSS/decanol/toluene system increased with increasing of sodium cholate and sodium salicylate concentrations, and it changed little with the sodium chloride concentration. The lnσ value exhibited a linear correlation with temperature in the range of 5-40 °C. No percolation threshold induced by temperature was detected either in the absence or in the presence of additives. Furthermore, the activation energy for conductivity was estimated and discussed according to the Arrhenius type equation. The present study would provide useful information for selecting a suitable template for nanometer materials preparation. [ABSTRACT FROM AUTHOR]

Abstract: The densities of binary mixtures of {isoamyl acetate+alcohols (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, and 2-butanol)}, including those of pure liquids, over the entire composition range were measured at temperatures (293.15 to 333.15)K and atmospheric pressure by means of a vibrating-tube densimeter. The excess molar volume, , thermal expansion coefficients, α, and their excess values, α E, were calculated from density data. The values are positive over the entire range of composition and temperature and become more positive with increasing temperature for all of the mixtures except for the (isoamyl acetate+methanol) mixture. The values were correlated by Redlich–Kister equation and the extended real associated solution (ERAS) model was used for describing values at T =303.15K. [Copyright &y& Elsevier]

multi-layer feed-forward artificial neural network has been presented for accurate prediction of the vapor liquid equilibrium (VLE) of CO+alkanol mixtures. Different types of alkanols namely, 1-propaol, 2-propanol, 1-butanol, 1-pentanol, 2-pentanol, 1-hexanol and 1-heptanol, are used in this study. The proposed network is trained using the Levenberg-Marquardt back propagation algorithm, and the tan-sigmoid activation function is applied to calculate the output values of the neurons of the hidden layers. According to the network's training, validation and testing results, a six layer neural network is selected as the best architecture. The presented model is very accurate over wide ranges of experimental pressure and temperatures. Comparison of the suggested neural network model with the most important thermodynamic correlations shows that the proposed neuromorphic model outperforms the other available alternatives. The predicted equilibrium pressure and vapor phase CO mole fraction are in good agreement with experimental data suggesting the accuracy of the proposed neural network model for process design. [ABSTRACT FROM AUTHOR]

Abstract: Densities and speeds of sound have been determined for the binary mixture (1-butylpyridinium tetrafluoroborate+methanol, or ethanol) over the temperature range 293.15K to 323.15K. From experimental values, excess volume and excess isentropic compressibility have been calculated. The mixtures give negative values for the excess properties. Besides, (vapour+liquid) equilibrium in isothermal conditions has been obtained for these systems at T =303.15K and T =323.15K, which has allowed us to derive activity coefficients and excess Gibbs functions. Positive deviations from Raoult’s law have been found. A detailed analysis and interpretation of results have been carried out in structural and energetic terms using thermodynamic information of the pure compounds. [Copyright &y& Elsevier]

Abstract: Some homogeneous liquid mixtures of an ionic liquid and a lower alkanol (e.g., methanol) can be forced to undergo a liquid–liquid phase split (resulting in a three-phase liquid–liquid–vapor (L1L2V) equilibrium) by pressurization with a gas. Such systems exhibit the phenomenon of “salting out by a nearcritical gas”. That phenomenon is often observed at temperatures around the critical temperature of the gas in liquid mixtures where at least one of the liquid components is a good solvent for that gas. New experimental results for both the L1L2V equilibrium and the corresponding critical endpoint lines of the two ternary systems (carbon dioxide+methanol+1-n-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF6]) and (carbon dioxide+1-butanol+1-n-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide [hmim][Tf2N]) at temperatures between 293 and 333K are reported. The experiments were performed with an “analytical method”. The liquid–liquid phase split exists only at pressures between a lower critical endpoint line (where both liquid phases become critical and coexist with a vapor phase) and an upper critical endpoint line (where one of the phases becomes critical with the vapor phase while the critical phases coexist with another liquid phase). The compositions of the coexisting three phases L1, L2, and V differ considerably; a high-density, ionic liquid-rich liquid phase (L1) coexists with an alkanol-rich liquid phase (L2) of lower density and a vapor phase (V) that is virtually ionic liquid-free. For both systems, it was observed that, at constant temperature, increasing pressure shifts the L1 phase towards higher contents of ionic liquid and gas and less alkanol, whereas in the L2 phase the mole fractions of ionic liquid and alkanol decrease. Higher temperatures result in a smaller difference between the pressures of both critical endpoint lines. Experimental results for both critical endpoint lines and for the compositions of the coexisting liquid phases are reported. [Copyright &y& Elsevier]

The refractive indices, n of binary mixtures of aniline with 1-propanol, 2-propanol, 2-methyl-1-propanol, 2-methyl-2-propanol, including those of pure liquids, covering the whole composition range have been measured at 293.15, 298.15, 303.15, 308.15, 313.15 and 318.15 K. From the experimental data, the deviations in refractive index, Δn has been calculated. The variation of Δn with composition and temperature of the mixtures has been discussed in terms of molecular interaction in these mixtures. It is observed that the extent of the deviation Δn for these mixtures follows the sequence: 1-propanol <2-propanol < 2-methyl-1-propanol < 2-methyl-2-propanol, indicating the presence of strong interactions in these mixtures in the same order. Further, the refractive indices of these binary mixtures were calculated theoretically from the refractive index data of pure components and densities of the mixtures by using various empirical and semi-empirical relations and the results were compared with the experimental findings. [ABSTRACT FROM AUTHOR]

The conductance behaviors of AOT in alkanol (hexanol, heptanol, octanol, and decanol) reverse microemulsions have been investigated. The percolation phenomenon induced by water is observed in the water/AOT/decanol system at 15°C and 30°C, and the water/AOT/octanol system at 15°C. The percolation phenomenon of water/AOT/alkanol systems is discussed from the interaction between the hydroxy group of alkanol and the polar group of AOT, droplets diffusion coefficient, and the rate constant for droplets collision. The droplets size and diffusion coefficient of the water/AOT/alkanol systems have also been studied by modifying the water concentration. The results show that hydrodynamic diameter of droplets decreases and diffusion coefficient increases with the increasing of water content, which may be explained by the polarity of alkanol phase. [ABSTRACT FROM AUTHOR]

Abstract: The experimental densities for the binary systems of an ionic liquid and an alkanol {1-ethyl-3-methylimidazolium ethylsulfate [EMIM]+ [EtSO4]− +methanol or 1-propanol or 2-propanol} were determined at T =(298.15, 303.15, and 313.15)K. The excess molar volumes for the above systems were then calculated from the experimental density values for each temperature. The Redlich–Kister smoothing polynomial was used to fit the experimental results and the partial molar volumes were determined from the Redlich–Kister coefficients. For all the systems studied, the excess molar volume results were negative over the entire composition range for all the temperatures. The excess molar volumes were correlated with the pentic four parameter virial (PFV) equation of state (EoS) model. [Copyright &y& Elsevier]

Water in oil microemulsion (μE) systems comprising water/AOT ± alkanol (n-butanol to n-dodecanol)/cycloalkanone (cyclopentanone to cycloheptanone, CA5, CA6, and CA7) were physicochemically studied with respect to phase and conductance behaviors. In absence of alkanols, AOT produced large clear zone with the cycloalkanones, compared to linear alkanes. Clear zone was comprised of gel, viscous, and clear fluid. Alkanols increased the fluidity of μE while its clarity was reduced. A maximum two-phase region was observed for n-heptanol (also for formulations with n-octanol). Salts, which reduced the clarity of the μE, followed the order of effectivity: Na+ < Mg2+ < Al3+. A correlation between clarity and turbidity was found irrespective of molecular size of oil, cosurfactant and salt. The influence of water and temperature on the conductance behavior of W/O formulations was studied. The studied systems were found to be less conducting than those with linear alkanes. Energetics and other structural parameters of the studied systems were evaluated from conductance behavior and the use of scaling equations. [ABSTRACT FROM AUTHOR]

Abstract: In an equilibrium vessel, the solubility of antioxidant 1010 in pure alkanols was measured in the temperature range from 283.15K to 343.15K using a method in which an excess amount of solute was equilibrated with the alkanol solution. The liquid concentrations of the investigated antioxidant 1010 in the saturated solution were analyzed by UV-spectrometry. The solubility data have been correlated as functions of the temperature. Activity coefficients for antioxidant 1010 have been calculated by means of the Wilson, NRTL and UNIQUAC equations and with them were correlated solubility data that were compared with the experimental ones. The best correlation of the solubility data has been obtained by the Wilson equation, by which the average root-mean-square deviation of temperature for the seven systems is 0.62K. [Copyright &y& Elsevier]

Abstract: The cationic complexes trans-[Pd(COOR)(H2O)(PPh3)2](TsO) have been synthesised by reacting cis-[Pd(H2O)2(PPh3)2](TsO)2·2H2O with CO in ROH (R=Me and Et), practically under room conditions, or by methathetical exchange of trans-[Pd(COOMe)Cl(PPh3)2] with Ag(TsO) (R= n-Pr, iso-Pr, n-Bu, iso-Bu, sec-Bu). They have been characterised by IR, 1H NMR and 31P NMR spectroscopies. The X-ray investigation of trans-[Pd(COOMe)(TsO)(PPh3)2] reveals that the palladium center is surrounded in a virtually square planar environment realized by two PPh3 trans to each other, the carbon atom of the carbomethoxy ligand and an oxygen atom of the p-toluensulfonate anion, with two crystallization molecules of CHCl3. The Pd–O–S angle, 151.9 (3)°, is very wide, probably due to the interaction of one CHCl3 molecule with the complex inner core. The carbomethoxy derivatives react with R′OH yielding the corresponding R′ carboalkoxy derivative (R′=Et, n-Pr and iso-Pr); ethene does not insert into the Pd–COOMe bond; decarbomethoxylation occurs when treated with TsOH/H2O in MeOH at 50°C. All the carboalkoxy are precursors for the catalytic carboalkoxylation of ethene if used in combination of PPh3 and TsOH, better in the presence of some water. Experimental evidences are more in favor of the so-called “hydride” mechanism rather than the “carbomethoxy” mechanism. [Copyright &y& Elsevier]

Abstract: Densities (ρ) and speeds of sound (u) for the binary mixtures of 1-hexanol with n-hexane, n-octane and n-decane have been measured over the entire composition range at 298.15, 303.15 and 308.15 K. The dynamic viscosities (η) for these systems have been measured at 298.15 K. From experimental data, excess molar volumes (V m E), molar isentropic compressibility (K s,m), excess molar isentropic compressibility (K s,m E), deviation in speed of sound (u D) from their ideal values (u id) in an ideal mixture, and excess free volumes (V f E) have been calculated. The excess functions have also been correlated with the Redlich–Kister polynomial equation. The viscosity data have been analysed in terms of some semi-empirical equations. The theoretical values of speed of sound (u) and isentropic compressibility (κ S) have also been estimated using the Prigogine–Flory–Patterson (PFP) theory with the van der Waals (vdW) potential energy model and the results have been compared with experimental values. The effect of chain-length of n-alkanes as well as the temperature on the excess properties has also been studied. [Copyright &y& Elsevier]

Abstract: This article presents a study of the behaviour in solution of 1-butyl-4-methylpyridinium tetrafluoroborate [b4mpy][BF4] in water and in the first five alkanols of the series methanol to pentan-1-ol. The excess enthalpies, and volumes, were determined at the temperatures (298.15 and 318.15)K. At these temperatures, the [b4mpy][BF4] was completely miscible in water, methanol, and ethanol, but only partially miscible in the other alkanols. A solubility study was carried out and the (liquid+liquid) equilibria of the ([b4mpy][BF4]+alkanol) systems were experimentally determined, evaluating zones of complete miscibility and determining the UCST in each case. The mixtures with water gave positive values of and , being also positive the changes of these quantities with temperature. The mixtures with alkanols gave values of and , and for these binary mixtures and . For all cases, results were interpreted and compared with data obtained in mixtures with another isomer [b3mpy][BF4]. Excess properties were correlated with a suitable equation and the area and volume parameters were calculated for [b4mpy][BF4]. [Copyright &y& Elsevier]

Abstract: This paper reports measurements of densities for the binary systems of an ionic liquid and an alkanol at T =(298.15, 303.15, and 313.15)K. The IL is trioctylmethylammonium bis(trifluoromethylsulfonyl)imide [OMA]+[Tf2N]− and the alkanols are methanol, or ethanol, or 1-propanol. The speed of sound at T =298.15K for the same binary systems was also measured. The excess molar volumes and the isentropic compressibilities for the above systems were then calculated from the experimental densities and the speed of sound, respectively. Redlich–Kister smoothing polynomial equation was used to fit the excess molar volume and the deviation in isentropic compressibility data. The partial molar volumes were determined from the Redlich–Kister coefficients. For all the systems studied, the excess molar volumes have both negative and positive values, while the deviations in isentropic compressibility are negative over the entire composition range. [Copyright &y& Elsevier]

Abstract: Excess molar enthalpy of acetonitrile+1-pentanol and acetonitrile+1-hexanol as a function of composition at 288.15, 293.15, 298.15 and 303.15 K under atmospheric pressure were used to test the applicability of the Prigogine–Flory–Patterson (PFP) model. The model, with only one adjustable parameter, shows to be able to correlate the experimental data of the investigated mixtures within a standard deviation up to 163 Jmol−1. The interactional contribution of the model plays the main role to describe the excess molar enthalpy and its ability of multiproperty description is not observed for the studied systems. [Copyright &y& Elsevier]

Abstract: Limiting activity coefficients in binary mixtures of six lower 1-alkanols (C1–C6) and ethylbenzene were determined employing alternatively the techniques of inert gas stripping and comparative ebulliometry. For each case, the suitable technique was chosen on the basis of the limiting relative volatility of the solute. Measurements were typically carried out at four temperatures covering a range of 30K and were done with a good precision (1–3%). The new data were compared with available literature information on both the activity coefficient and calorimetric partial molar excess enthalpy at infinite dilution. All the critically evaluated information was merged and processed simultaneously to produce the recommended temperature dependences of the limiting activity coefficients. The performance of leading prediction methods (UNIFAC, modified UNIFAC, ASOG, MOSCED, DISQUAC) was further examined using this data. [Copyright &y& Elsevier]

Abstract: Although 1-alkanols have long been known to act as penetration enhancers and anesthetics, the mode of operation is not yet understood. In this study, long-time molecular dynamics simulations have been performed to investigate the effect of 1-alkanols of various carbon chain lengths onto the structure and dynamics of dimyristoylphosphatidylcholine bilayers. The simulations were complemented by microcalorimetry, continuous bleaching and film balance experiments. In the simulations, all investigated 1-alkanols assembled inside the lipid bilayer within tens of nanoseconds. Their hydroxyl groups bound preferentially to the lipid carbonyl group and the hydrocarbon chains stretched into the hydrophobic core of the bilayer. Both molecular dynamics simulations and experiments showed that all 1-alkanols drastically affected the bilayer properties. Insertion of long-chain 1-alkanols decreased the area per lipid while increasing the thickness of the bilayer and the order of the lipids. The bilayer elasticity was reduced and the diffusive motion of the lipids within the bilayer plane was suppressed. On the other hand, integration of ethanol into the bilayer enlarged the area per lipid. The bilayer became softer and lipid diffusion was enhanced. [Copyright &y& Elsevier]

Abstract: The interaction parameters between group chloro (–Cl) and hydroxyl (–OH) for the group contribution model of Nitta et al. 1977 (Nitta–Chao model) have been estimated with the use of a data base of experimental thermodynamic properties. The results obtained by the Nitta–Chao model with these new parameters were compared with predictions by other models such as UNIFAC model (versions of Dang and Tassios 1986, Larsen et al. 1987 and Gmehling et al. 1993). [Copyright &y& Elsevier]