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Natural aragonite was used as a support for different percentages (5%, 10% and 20%) of nano-Ni which obtained from nickel nitrate and reduced by hydrazine hydrate. It was demonstrated that the 20% catalyst has higher activity compared to other nickel percentages for the reduction of p-nitrophenol to p-aminophenol. The reduction process was performed in alkaline medium (NaOH) by using hydrazine hydrate as a source of hydrogen. The catalysts were characterised by using XRD, SEM, FT-IR and XRF. In order to discuss the kinetics of reduction process, the effect of the catalysts load and p-nitrophenol concentration on the initial reduction rate were studied. The value of rate constant, reaction order and the activation energy were estimated. Moreover, thermodynamic functions at different temperatures were obtained. The proposed reaction mechanism was postulated. [ABSTRACT FROM AUTHOR]

The complex dielectric permittivity of Polyvinylpyrrolidone (PVP K-30) [C6H9ON]n in four different alcohols (methanol, ethanol, propanol, and butanol) with no. of carbon atoms ranging from one to four has been determined in the frequency range of 10 MHz to 50 GHz over the temperature range of 278.15–298.15 K at various concentrations of PVP (C) using time-domain reflectometry technique. The dielectric permittivity spectra were described using the Cole-Davidson model. Two modes of relaxation processes were observed, namely low-frequency (secondary) and high-frequency (primary) relaxation. The low-frequency relaxation is due to the interaction between solute–solvent molecules, whereas the reorientation of solvent molecules is responsible for the high-frequency dispersion of relaxation. By using the Harviliak-Negami equation, the frequency-dependent complex dielectric permittivity has been studied. Dielectric parameters such as static dielectric constant (εj), relaxation time (τj), dipole moment (û), Kirkwood correlation factor (g1), number of solvent molecules irrotationally bound to solute molecules (Zib), and effective volume of rotation (Veff) were determined. In addition to this, thermodynamic properties such as the free energy of activation (ΔFj), enthalpy of activation (ΔHj), and entropy of activation (ΔSj) were also calculated. It was observed that the low-frequency static dielectric constant (εl) increases with the PVP concentration in all cases except in methanol. εl values strongly depend on the temperature, and they increase as the temperature of the system decreases, whereas the high-frequency dielectric constant (εh) increases towards higher concentrations of solute molecule as well as towards lower temperatures. [ABSTRACT FROM AUTHOR]

The impact of different concentrations of natural antioxidants (curcumin) on the thermal stability of UHMWPE (ultra-high molecular weight polyethylene) is examined via the thermogravimetric (TGA/DTA) technique, in the temperature region 50–600 °C at a 5 °C/min heating rate. This work employs the model fitting (Coats and Redfern) approach to determine the optimal curcumin concentration. UHMWPE samples at optimum concentration are further subjected to three other heating rates, viz., 10, 15 and 20 °C. A bi-Gaussian asymmetric function is utilized for deconvolution to elucidate the complexities of thermal decomposition. Through deconvolution, two peaks are obtained and the activation energy corresponding to each peak is determined through two iso-conversional kinetic (Friedman and Starink) models. By utilizing activation energy, the random nucleation reaction mechanism involved in thermal decomposition is recognized. Finally, changes in entropy Δ S , enthalpy Δ H and Gibbs free energy Δ G are determined. [ABSTRACT FROM AUTHOR]

Lead (Pb+2) ions considered a crucial neurotoxic heavy metal result in serious troubles in the live biological environment including poisoning, and liver and kidney shortage, in addition to anemia, hepatitis, encephalopathy, and renal syndrome. In the current study, the biomass of Zea mays (ZMS) was prepared as a biosorbent for the elimination of Pb+2 ions from the aquatic environment in batch mode relevant to contact time, pH solution, biosorbent dose, and temperature. The Zea mays biomass was characterized using an SEM microscope coupled with EDX, FTIR, XRD, and BET surface area analysis to investigate the modification of chemical structure for the biosorption system. According to the biosorption experiments, the supreme biosorbent capability of ZMS approaches 16.9 mg/g for 180 min at pH = 5.5. The evaluation of kinetics analysis reveals that the (Pb+2) biosorption by ZMS was better described with pseudo-second-order kinetics. In addition, the nonlinear regression of Freundlich, Langmuir, Temkin, and Elovich isothermal models was modeled to the equilibrium data, and it was deduced that the Langmuir isotherm provides a better fit than Langmuir based on the correlation coefficient values. The thermodynamic factors were calculated for this biosorption process in which the lead ions are sequestered by the ZMS. According to these factors, it was elucidated that the (Pb+2) ions biosorption onto the Zeamays sponge is exothermic and spontaneous. In addition, Monte Carlo (MC) simulations were conducted to screen the adsorption competence of pigments and ligands in Zea mays for Pb+2 ions adsorption. The outputs of experimental and simulation studies proved the potentiality of Zea mays sponge (ZMS) as a promising biosorbent for eliminating heavy metallic elements from aqueous media. [ABSTRACT FROM AUTHOR]

The micellization properties of rhamnolipids (RLs) in extreme electrolyte concentrations and temperatures have gained considerable attention due to their broad industrial applications. In this study, the aggregation behavior, specifically the micellization pattern (critical micelle concentration (CMC)) of RLs produced from a newly isolated thermophilic strain of Pseudomonas aeruginosa from a harsh environment of an oil field, was investigated by a spectrophotometric method at various temperatures (293–393 K) and electrolyte concentrations (NaCl: 2–20%). The result indicated that the CMC values (0.267–0.140 mM⋅dm−3) were both electrolyte- and temperature-dependent exhibiting a U-shaped trend as temperature and NaCl concentration increased. Variations in NaCl concentration and temperature also affected the standard Gibbs free energy (Δ Gomic), enthalpy (Δ Homic), and entropy (Δ Somic) of micellization. The molecule also showed stability at a broad range of temperatures, pH, and NaCl concentrations. Thin-layer chromatography (TLC) and Fourier-transform infrared (FTIR) analysis confirmed the similarity in composition between the crude extract and the commercial RL with Rf values of 0.72 for mono-rhamnolipids and 0.28 for di-rhamnolipids. FTIR analysis confirmed the chemical nature particularly key aliphatic functional groups present in the fatty acid tail of RLs and the -COC- bond in the structure of the rhamnose moiety. Additionally, LC-ESI-QTOF analysis confirmed corresponding ionic fragments of mono- and di-rhamnolipids congeners. Furthermore, the antimicrobial potential was determined against different human pathogens in the absence and presence of NaCl by measuring zones of inhibition. The result revealed enhanced inhibitory effects against Gram-positive pathogens (S. aureus , S. epidermidis , and L. monocytogene), with zones of inhibition of 26, 30, and 20 mm in the presence of NaCl. These findings underline the role of NaCl in the micellization of RL molecules and highlight their importance in environmental applications, pharmaceuticals, and various life science sectors. [ABSTRACT FROM AUTHOR]

The dielectric, thermodynamic and volumetric measurements of neat 2-ethoxyethanol, neat ethanol and their binary mixtures have been carried out using time domain technique at 10°C–25°C with a variation of 5°C. Various dielectric parameters are calculated from complex dielectric spectra and are used to compute Kirkwood correlation factor, Bruggeman factor and activation thermodynamic parameters. These parameters are used to predict heteromolecular hydrogen bonding between associating molecules. The classical and non-classical type H-bonding interactions among the molecules are predicted using FT-IR spectroscopy. [ABSTRACT FROM AUTHOR]

ABSTRACT Background Aims Methods Results Conclusions Soil enzymes are key to predicting nutrient availability and forest fertility.We aimed to evaluate the influence of forest type on the kinetic and thermodynamic characteristics of soil enzymes.Soils were sampled at 0–10 and 10–20 cm depth from two pure forests (Pinus tabulaeformis [PTF] and Quercus acutissima [QAF]) and a mixed forest of PTF and QAF (MF) on the Chinese Loess Plateau. Kinetic parameters (maximum enzyme activity [Vmax], half‐saturation constant [Km], and enzyme efficiency [Kcat]) and thermodynamic parameters (temperature coefficient [Q10] and activation energy [Ea]) of β‐1,4‐glucosidase (BG), β‐1,4‐N‐acetylglucosaminidase (NAG), l‐leucine aminopeptidase (LAP), and alkaline phosphatase (AP) were determined.Forest type exerted significant influence on soil enzyme kinetic parameters. The Vmax and Kcat values of BG, NAG, and AP in PTF of 0–10 cm soil depth were 42.54% and 59.22%, 77.18% and 23.08%, and 62.82% and 58.21% higher than that in MF, respectively. The Vmax of AP and Kcat of NAG in PTF of 10–20 cm depth were 34.61% and 39.90% higher than that in MF. The soil enzyme thermodynamic parameters were significantly influenced by forest type and soil depth. At 0–10 cm depth, low values of Q10–Vmax and Q10–Km of BG, Q10–Vmax and Q10–Kcat of NAG, and Ea of BG and NAG were found in PTF. At 10–20 cm depth, low values of Q10–Vmax, Q10–Kcat, and Ea of BG and NAG were found in MF.PTF was more effective in promoting soil enzymatic reactions, especially in surface soil. MF improved subsoil enzyme thermal stability and reduced temperature sensitivity. The study showed that pure and mixed forests affect soil enzyme characteristics differently, with soil depth as a key factor. [ABSTRACT FROM AUTHOR]

The dielectric measurements of thiamine hydrochloride (vitamin B1 hydrochloride) and dimethyl sulphoxide (DMSO) binary mixtures have been carried out in the frequency range of 10 MHz to 50 GHz at 25°C, 20°C and 15°C using the TDR technique. The dielectric parameters such as complex dielectric permittivity ɛ*(ω), static dielectric permittivity (ɛs), relaxation time (τ), and asymmetric distribution parameter (β) are obtained by using Cole-Davidson model. These parameters are used to compute thermodynamic properties, Kirkwood correlation factor (geff), and excess molar volume (VE). The heteromolecular H-bonding existing in the binary mixture is explained. [ABSTRACT FROM AUTHOR]

Cluster formation has significant implications in atmospheric science and environmental chemistry. These clusters are characterized by complex interactions between their constituents, which influence their structure, stability, and growth. Experimental investigations are difficult for the initial stages of prenucleation cluster formation, which leads to larger aerosols. To understand the formation of clusters, the interactions between sea salts (NaCl, KCl, and MgCl2), water, and sulfuric acid molecules have been investigated. Each step has been comprehensively examined and thermodynamic parameters have been computed using DLPNO‐CCSD(T)/CBS//M06‐2X/6‐311++G(3df,3pd) to find the stabilities of the molecular complexes. Among all complexes, the binding energies of cluster (SS)1(W)1(SA)3 are found to be the lowest due to the formation of HCl, hydrogen bonding, and weak van der Waal forces. Sea salts have shown a more favorable interaction with H2SO4 compared to H2O molecules. The addition of H2SO4 increases the reactivity of the cluster (SS)1(W)n, while the addition of H2O molecules reduces the reactivity of the cluster (SS)1(SA)n. However, further addition of H2SO4 or H2O to the existing cluster (SS)1(W)n(SA)n increases the free energy of formation. Furthermore, the influence of temperature was also investigated, suggesting that complex formation is slightly more favorable at lower temperatures than at higher temperatures. The negative values of thermodynamic parameters indicate, that these complexes are spontaneous and exothermic over the colder regions. [ABSTRACT FROM AUTHOR]

Expressions for the thermodynamic potentials (TPs) of small systems are traditionally used in thermodynamics by analogy with TPs of ordinary macro-phases. This form of introducing TPs for small systems eliminates their specificity consisting in the presence of dimensional dependences for TP values and all other thermodynamic functions. To take into account the sizes of small systems in the traditional method of introducing TPs, it is necessary to explicitly reflect the presence of an interface and the associated heterogeneity of the internal local properties of a small system. The general case is discussed when dimensional dependences of TPs of small systems in limited volumes are introduced, with macroscopic concepts of the phase and the interface non-autonomy being preserved. Options are considered to introduce size dependences into TPs of small droplets and separated fluid phases inside pores. [ABSTRACT FROM AUTHOR]

This research begins with the initial assessment of key physical properties—density (ρ), speed of sound (u), and refractive index (nD) in binary aqueous solutions of dorzolamide hydrochloride. These properties were measured in solutions with varying molalities, ranging from 0.0 to 0.0276, under standard atmospheric conditions and at temperatures between 300.15 and 320.15 K. From these measurements, we were able to calculate a range of important parameters, including the apparent molar volume (Vϕ), its limiting values ( V ϕ 0 ), limiting apparent molar expansivity ( E ϕ 0 ), Helper's constant ( ∂ 2 V ϕ 0 ∂ T 2 ), apparent molar isentropic compression (κϕ), and its limiting values ( κ ϕ 0 ), specific refraction (RD), molar refraction (RM), and hydration number (nh). These calculated values provided insights into the strong interactions between the solute and solvent in the liquid system. They also shed light on the presence of various molecular interactions, such as inter- and intramolecular hydrogen bonds, dipole–dipole, and dipole-induced-dipole interactions, as well as the ability of the solute to influence the structure of the surrounding water molecules. Additionally, we derived the densities of dorzolamide hydrochloride solutions from molecular dynamics (MD) simulations, which showed a strong correlation with our experimental findings, underscoring the reliability of MD simulations in such studies. In the end, our combined study on dorzolamide hydrochloride in water demonstrates that it shapes structures because it has lower volumetric properties and stronger hydrogen bonds in MD simulations. More alchemical free energy calculations show that there are big changes in solvation energies. This is important for understanding how dorzolamide hydrochloride works in water. [ABSTRACT FROM AUTHOR]

Organic inhibitors play a crucial role in the corrosion inhibition process. In this work, the performance of the derivative of quinoline PPMQ against corrosion of carbon steel in the acidic medium HCl 1 M was assessed using electrochemical methods. The findings of the experiments showed that the inhibitor had a strong inhibitory impact on the metal tested in the hydrochloric acid solution. The outcomes of the study displayed that the inhibition efficiency of the tested inhibitor enhanced with its concentrations and remained almost stable during immersion time while decreasing slightly with rising temperature. Electrochemical measurements of this study showed that the corrosion was greatly decreased by the organic inhibitor through a charge transfer mechanism with a high inhibition efficiency of 95.58% at an optimal concentration of 10-2 M at 293 K. While potentiodynamic polarization data reported that the inhibitor was a mixed-type inhibitor. PPMQ was inclined towards the Langmuir adsorption isotherm by spontaneous chemical-physical adsorption on the surface of carbon steel. Additionally, thermodynamic and activation data revealed that this action occurs through an endothermic process. Scanning electron microscopy findings showed that the inhibitor's molecules form a protective layer, which confirms the electrochemical results. [ABSTRACT FROM AUTHOR]

Urea, as a nonelectrolyte molecular solute in aqueous solutions, has a vital role in the thermodynamic, thermophysical and physiochemical studies. To a large extent, addition of Urea to water does not alter the structural dynamics of water. Only a little amount of water molecules is supposed to be closely associated with urea molecules. Therefore, study of intramolecular as well as intermolecular interactions in the binary aqueous urea solution by conducting thermophysical and thermodynamic investigations is quite important. In this work, new experimental data on water activity for solutions containing urea under precisely controlled conditions and derived thermodynamic parameters were reported. Water activity of urea was also estimated from the Kirkwood–Buff integrals in a novel way. [ABSTRACT FROM AUTHOR]

In this paper, the atomic structure and thermodynamic property aspects of the high-temperature melts of Ni-Zr alloys with different compositions are investigated using molecular dynamics simulations to analyze the factors affecting their amorphous formation ability. By observing the change of the average atomic volume with temperature during the cooling process and the change of the proportion of amorphous structure in the visual analysis of the configuration at 300 K, it is found that the amorphous formation ability of Ni-Zr alloy shows a significant decrease and then rebound in the interval of 60%-90% of Ni content. The thermodynamic parameters such as mixing enthalpy, mixing entropy, and mixing free energy did not show significant correlation with the amorphous formation ability, and the change of the second-order partial derivative of the mixing free energy reflected that the change of the thermodynamic factors significantly affected the amorphous formation ability. The structural parameters such as two-body distribution function and coordination number, which are closely related to the amorphous formation ability, show a weak correlation, and the Warren-Cowley parameter and bond length analysis reveal that the variation of Ni-Zr bond shows the same trend with the amorphous formation ability. This study is helpful to deepen the understanding of the relationship between high-temperature melting and amorphous formation ability of alloys. [ABSTRACT FROM AUTHOR]

In this work, the solubility of glibenclamide in the non-aqueous mixtures of carbitol and 1-propanol was studied at temperatures ranging from 293.2 K to 313.2 K using a shake-flask technique. The findings were represented by five computational models, including the van’t Hoff, the Jouyban-Acree, the Jouyban-Acree-van’t Hoff, the mixture response surface and the modified Wilson models. These models showed strong correlation and prediction capabilities, as indicated by the mean relative deviations for the back-calculated data. Furthermore, the thermodynamic analysis was conducted for solubility data using van’t Hoff and Gibbs equations. [ABSTRACT FROM AUTHOR]

This study starts by evaluating essential physical characteristics—density (ρ), sound velocity (u), and refractive index (nD)—in binary mixtures of Moxifloxacin Hydrochloride with water. We measured these properties in solutions with different concentrations, from 0.0 to 0.05 molalities, under normal atmospheric pressure and at temperatures from 305.15 to 320.15 K. From these measurements, we were able to calculate a range of important parameters, including the apparent molar volume V ϕ , its limiting values V ϕ 0 , limiting apparent molar expansibility E ϕ 0 , Hepler's constant ∂ 2 V ϕ 0 ∂ T 2 , apparent molar adiabatic compressibility k ϕ and its limiting values k ϕ 0 , specific refraction R D , molar refraction R M and hydration number n h . The calculated values demonstrated dominant solute–solvent interactions in the liquid mixture in this study. These findings indicated that molecules interact through hydrogen bonds, dipole–dipole interactions, and dipole-induced dipole interactions. They also showed how the solute influences the structure of water molecules. Moxifloxacin Hydrochloride (MOX) solution densities have been determined by MD simulations. These simulations matched our experimental data, proving MD simulation's effectiveness in such investigations. Finally, our in-depth research of MOX in water shows that it changes the way structures are made because it has lower volumetric properties and stronger hydrogen bonds, as seen in MD simulations. Solvation energies changed a lot when we did more calculations of alchemical free energy. These changes are very important for understanding how MOX behaves in water. [ABSTRACT FROM AUTHOR]

Present study determines the Critical Micelle Concentration (CMC) of some market available detergents at different temperatures in aqueous solutions. For this study we use Sunlight Surf and Safed Surf. Sodium Acetate Electrolyte was used. Conductance data was taken at different temperatures (15°C, 25°C, 35°C). From this study it was observed that with increase in temperature, cmc value decreases. Addition of electrolyte with surfactants (detergent), decrease cmc value which support our basic concept of surface chemistry. Different thermodynamic parameters like, ΔG, ΔH, ΔS were calculated and also supporting the formation of cmc. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) and its composites have been widely studied for environmental applications, including for dye removal. In this study, various GO‐based materials namely GF, GFA, and GFC were successfully synthesized and characterized by FTIR, Raman spectroscopy, FESEM, BET, and TGA methods before and after being used to adsorb methylene blue from aqueous solutions. The BET results reveal that MB molecules most filled in the pores at the size of 100–300 nm of the materials. The adsorption process followed the pseudo‐first‐order equation and Sips isothermal model for all the materials. However, GFA showed the maximum adsorption capacity (Qmax=739 mg/g) and the most negative value of ΔG while the least effective material was GFC. The experiment revealed that GF and GFA could remove up to 95.0 % color on the real textile wastewater sample, and the materials are very promising for dye removal application. [ABSTRACT FROM AUTHOR]

This study investigates the temperature‐dependent micellization behaviors of saponin and sodium dodecyl sulfate (SDS) surfactants, which are both important for chemical enhanced oil recovery (CEOR). It also evaluates the effect of silica nanoparticles (SiO2) on these behaviors, given the growing interest in nanoparticle‐enhanced surfactants. The research focuses on the tunable properties of nanoparticle‐surfactant combinations. The structural differences between saponin and SDS were identified using FT‐IR and H‐NMR. The Du Noüy ring method was used to measure surface tension at various concentrations and temperatures (25–75 °C). FTIR analysis showed distinct differences between SDS and Saponin, associated with head group where there is hydroxyl groups in SDS solution. H‐NMR showed higher complexity of Saponin's structure, evidenced by its diverse sugar‐related proton peaks. Both SDS and Saponin reduce surface tension with temperature; SDS is more effective, lowering it to 42.1 mN/m versus 48.5 mN/m for Saponin. With SiO2, tensions drop to 39.2 mN/m for SDS and 45.5 mN/m for Saponin. Both surfactants maintain CMCs under reservoir temperature in the 0.05–0.1 wt % range. Saponin exhibited a more negative ΔG° and consistently negative ΔH°, indicating a thermodynamically favorable exothermic reaction. The novelty of this study lies in its focus on both anionic and nonionic surfactants under simulated reservoir conditions. The study focuses on the role of nanoparticles in enhancing surfactant stability and efficiency by addressing thermodynamic parameters. [ABSTRACT FROM AUTHOR]

A laboratory experiment was carried out to study the ability of soil to adsorption of Zinc added from three sources: nano-Zinc oxide (ZnnO), nano-chelated Zinc (Znn-DTPA), and nano-organic Zinc (Znn-HA), with several concentrations ranging from 0-160 mg Zn kg-1. Zinc was added for each concentration at an amount of 20 ml per 1 gm of soil. As for the ordinary sources, Zinc was added from the ordinary sources, Zinc oxide, ZnO, chelated Zinc, Zn-DTPA, and ordinary organic Zinc, Zn-HA, in several concentrations, ranging from 0-500 mg Zn kg-1. Each concentration was added at 20 ml per 1 gm of soil and two repetitions for each source. The adsorption capacity of the soil and the binding energy of the adsorbed Zinc, and to estimate the thermodynamic parameters for the adsorption of nano-Zinc in desert soils, and Freundlich equations were used to study and evaluate the adsorption process. The thermodynamic parameters Kº, ΔGº, ΔHº, and ΔSº were calculated based on the results of the adsorption experiment. The results of the experiment indicate that both equations succeeded in describing the adsorption of nano and ordinary Zinc depending on the value of the determination coefficient of (R² ), which ranged between (0.959 - 0.971) and (0.884 - 0.985) for each of the Langmuir and Freundlich equations respectively. As for the thermodynamic equilibrium constant Kº, it decreased with the increase in the reaction temperature for three sources: Znn-DTPA, ZnO, and Zn-HA, while it increased with the other three sources. The negative ΔGº values for all sources of nano and ordinary Zinc parameters spontaneity of the reaction at both temperatures 25°C - 45°C. [ABSTRACT FROM AUTHOR]

Herein, the micellization characteristics of tetradecyltrimethylammonium bromide (TTAB) and promethazine hydrochloride (PMH) mixtures have been explored in the presence of various hydrotropes (HyTs) (sodium salicylate (NaS), sodium benzoate (NaB), and p-amino benzoic acids (4-AmBA)) by applying the conductivity measurement method. The investigation was carried out by varying the composition of HyTs at definite temperature as well as variable temperatures while the composition of HyTs remained unchanged. The influences of hydrotropes and temperatures on the micellization of TTAB and PMH mixture have been examined from the changes in physico-chemical parameters of the respective system with the variation in composition/nature of HyTs and temperatures. A single critical micelle concentration (CMC) was noted for the employed drug + surfactant mixture in the appearance of HyTs. The introduction of NaS disrupted the micelle development whereas the presence of NaB and 4-AmBA promoted micelle formation in TTAB and PMH mixtures. At 6 mmol kg−1 concentration of HyTs, the magnitudes of CMC demonstrated the order of CMC as (aq. NaS) > CMC aq. NaB > CMC aq. 4 - AmBA. The CMC values of PMH + TTAB mixtures showed significant changes with the augmentation of temperatures. The appearance of negative Δ G m 0 apparently indicating the spontaneous nature of aggregation of surfactant species. Other thermodynamic parameters such as enthalpy change ( Δ H m 0 ), entropy change ( Δ S m 0 ), molar heat capacity ( Δ C m , P 0 )), thermodynamics of transfer and enthalpy-entropy compensation quantities have also been determined and the results were described in detail. The interaction forces among the components within the studied system were found to be electrostatic and hydrophobic in nature. [ABSTRACT FROM AUTHOR]

Phytochemical-rich natural extracts have recently attracted intense attention as green corrosion inhibitors and costly benign coating components for the protection of metallic structures of immense commercial importance. Herein, various methods were applied to assess the corrosion protection efficiency of a methanolic extract of parsley (Petroselinum crispum) (PCE) on carbon steel C37 in 1 M HCl. Initially, the chemical profile of PCE was analyzed using gas chromatography/mass spectrometry (GC/MS), and myristicin and apiol were identified as the main components. The results from the weight loss, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP) techniques revealed a substantial reduction in the corrosion rate upon the use of PCE, with a maximum inhibition efficiency of 92% at 1 g L−1 PCE. To optimize the performance, the corrosion behavior was investigated over a temperature range of 303–333 K and for concentrations of 0.1–1 g L−1. The inhibition effectiveness increased at higher concentrations of PCE, whilst it decreased when the temperature was elevated. The query suggests that the adsorption process involves both physical and chemical mechanisms. The adsorption of PCE onto C37 was well described by the Langmuir adsorption isotherm. The data were used to determine the activation energy and thermodynamic parameters. The PCE coating acted as a mixed-type inhibitor, hampering both cathodic and anodic corrosion reactions. SEM further confirmed the formation of a protective coating film on the steel surface when exposed to PCE. UV-Vis and XRD were implemented to understand the inhibition mechanism and formed products at the microscopic and spectroscopic levels. Hence, the green PCE inhibitor may potentially be applied in corrosion mitigation due to its high corrosion protection efficacy and its environmentally benign nature. [ABSTRACT FROM AUTHOR]

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In the present work, the thermodynamic parameters for the adsorption of 2,4-dichlorophenoxyacetic acid (2,4-D), a herbicide, onto biomass-based activated carbon coated with magnetite nanoparticles (ACM) were estimated using a high-precision isothermal titration calorimeter (ITC). The obtained thermodynamic parameters, such as change in Gibb's free energy (ΔG), change in enthalpy (ΔH), and change in entropy (ΔS), were compared with the values computed applying conventional methods using equilibrium isotherm model parameters. The thermodynamic parameters suggested that the adsorption of 2,4-D onto ACM was spontaneous and exothermic. ITC proved to be an efficient experimental method in determining the thermodynamic parameters for the adsorption process with minimal adsorbent, adsorbate, and time consumption. The application of ITC can also be extended to determine the thermodynamic parameters of various solid–liquid interactions involved in different processes. Practical Applications: The 2,4-dichlorophenoxyacetic acid (2,4-D) is commonly used as a herbicide, and its occurrence is reported widely in aquatic bodies. Adsorption process using activated carbon impregnated with iron nanoparticles proved to be effective in removing these 2,4-D from the aquatic phase. In general, adsorption dynamics are demonstrated by isotherm, kinetics, and thermodynamic studies so that it can be extended to real-world applications. Conventionally, adsorption thermodynamic parameters are estimated from equilibrium isotherm constants. However, the determination of these parameters using the isotherm constants may not be accurate. Hence, sophisticated equipment such as isothermal titration calorimeter (ITC) can be used as an efficient tool to accurately compute the thermodynamic parameters in less time with minimal requirement of reagents. [ABSTRACT FROM AUTHOR]

Lightweight high-entropy alloys (LWHEAs) present new opportunities for exploring innovative, low-cost materials with a high strength-to-weight ratio, thanks to their expansive alloy-design space. This study introduces the newly designed AlMgxTiSnZn HEAs to examine the relationship between microstructure, phase stability, and functional properties (including mechanical, thermal, and electrochemical properties alongside oxidation resistance). These alloys were produced by mechanically mixing them in a high-energy ball mill (HEBM), followed by heating with spark plasma sintering (SPS). Thermodynamic calculations were utilized to ascertain the phase structure. XRD studies revealed a predominant ordered BCC phase with minor peaks indicating a tetragonal structure. The correlation between microhardness (Hv) and fracture strength (σf) with Mg content indicates that the HEA sample featuring the highest microhardness concurrently exhibits the highest fracture strength (AlMgTiSnZn). This AlMgTiSnZn HEA sample, noted for its high corrosion resistance and distinct properties (such as favorable over-potential, low corrosion current density (Icorr), and minimal corrosion rate), is particularly promising for high-temperature applications.

The micellization properties of rhamnolipids (RLs) in extreme electrolyte concentrations and temperatures have gained considerable attention due to their broad industrial applications. In this study, the aggregation behavior, specifically the micellization pattern (critical micelle concentration (CMC)) of RLs produced from a newly isolated thermophilic strain of Pseudomonas aeruginosa from a harsh environment of an oil field, was investigated by a spectrophotometric method at various temperatures (293–393 K) and electrolyte concentrations (NaCl: 2–20%). The result indicated that the CMC values (0.267–0.140 mM⋅dm−3) were both electrolyte- and temperature-dependent exhibiting a U-shaped trend as temperature and NaCl concentration increased. Variations in NaCl concentration and temperature also affected the standard Gibbs free energy (ΔGomic), enthalpy (ΔHomic), and entropy (ΔSomic) of micellization. The molecule also showed stability at a broad range of temperatures, pH, and NaCl concentrations. Thin-layer chromatography (TLC) and Fourier-transform infrared (FTIR) analysis confirmed the similarity in composition between the crude extract and the commercial RL with Rf values of 0.72 for mono-rhamnolipids and 0.28 for di-rhamnolipids. FTIR analysis confirmed the chemical nature particularly key aliphatic functional groups present in the fatty acid tail of RLs and the -COC- bond in the structure of the rhamnose moiety. Additionally, LC-ESI-QTOF analysis confirmed corresponding ionic fragments of mono- and di-rhamnolipids congeners. Furthermore, the antimicrobial potential was determined against different human pathogens in the absence and presence of NaCl by measuring zones of inhibition. The result revealed enhanced inhibitory effects against Gram-positive pathogens (S. aureus, S. epidermidis, and L. monocytogene), with zones of inhibition of 26, 30, and 20 mm in the presence of NaCl. These findings underline the role of NaCl in the micellization of RL molecules and highlight their importance in environmental applications, pharmaceuticals, and various life science sectors.

The thermodynamics of protein–ligand interactions seems to be associated with a narrow range of Gibbs free energy. As a consequence, a linear enthalpy–entropy relationship showing an apparent enthalpy–entropy compensation (EEC) is frequently associated with protein–ligand interactions. When looking for the most negative values of ∆H to gain affinity, the entropy compensation gives rise to a barely noticeable increase in affinity, therefore negatively affecting the design and discovery of new and more efficient drugs capable of binding protein targets with a higher affinity. Originally attributed to experimental errors, compensation between ∆H and T∆S values is an observable fact, although its molecular origin has remained obscure and controversial. The thermodynamic parameters of a protein–ligand interaction can be interpreted in terms of the changes in molecular weak interactions as well as in vibrational, rotational, and translational energy levels. However, a molecular explanation to an EEC rendering a linear enthalpy–entropy relationship is still lacking. Herein, we show the results of a data search of ∆G values of 3025 protein–ligand interactions and 2558 “in vivo” ligand concentrations from the Protein Data Bank database and the Metabolome Database (2020). These results suggest that the EEC may be plausibly explained as a consequence of the narrow range of ∆G associated with protein–ligand interactions. The Gaussian distribution of the ∆G values matches very well with that of ligands. These results suggest the hypothesis that the set of ∆G values for the protein–ligand interactions is the result of the evolution of proteins. The conformation versatility of present proteins and the exchange of thousands (even millions) of minute amounts of energy with the environment may have functioned as a homeostatic mechanism to make the ∆G of proteins adaptive to changes in the availability of ligands and therefore achieve the maximum regulatory capacity of the protein function. Finally, plausible strategies to avoid the EEC consequences are suggested.

Abstract This study aimed to measure both the solubility and thermodynamics of salicylic acid in binary solvent mixtures of (2-propanol + ethylene glycol) and (2-propanol + propylene glycol) at different temperatures in the range of 293.2–313.2 K. The experimental solubility data were analyzed using various linear and nonlinear cosolvency models, such as the van’tt Hoff, Jouyban-Acree, Jouyban-Acree-van’tt Hoff, mixture response surface and modified Wilson models and to evaluate the models, the mean relative deviations of the back-calculated solubility data were compared with experimental values. Through this analysis, the apparent thermodynamic parameters, including Gibbs energy, enthalpy, and entropy were calculated using the van’tt Hoff and Gibbs equations for this system. Additionally, the density values for salicylic acid saturated mixtures were also measured and represent mathematically using the Jouyban-Acree model.

This review focuses on thermodynamic and physical parameters, synthesis methods, and reported phases of Magnesium (Mg) containing high-entropy alloys (HEAs). Statistical data of publications concerning Mg-containing HEAs were collected and analyzed. Data on the chemical elements included in Mg-containing HEAs, their theoretical end experimental densities, thermodynamic parameters, physical parameters, fabricated techniques and reported phases were also collected and discussed. On the basis of this information, a new classification for HEAs was proposed. It is also shown that the existing thermodynamic parameters cannot accurately predict the formation of a single phase solid solution for Mg-containing HEAs. The physical parameters of Mg-containing HEAs are within a wide range, and most of the synthesized Mg-containing HEAs have a complex multiphase structure.

The complex dielectric permittivity spectra (CPS) of a binary mixture of 1,5-pentanediol (1,5-PD) with 1,4-dioxane (1,4-DX) were determined using time-domain reflectometry in the frequency range of 10 MHz to 30 GHz. The experimental CPS data were fitted to the Cole–Davidson equation using a nonlinear least squares fit method to determine the dielectric relaxation parameters. The intermolecular interactions in the binary liquids were studied through the Kirkwood correlation factor, excess parameters, thermodynamic parameters, and Bruggeman's factor. [ABSTRACT FROM AUTHOR]

Three direct –NSO3H functionalized Brønsted acidic ionic liquids of 2-alkyl-1,3-disulfo imidazolium chloride with varied sizes of alkyl substituents (Me-, Et-, nBu-) were utilized to explore the effects of ionic liquids on aggregation behavior of anionic surfactant sodium dodecyl sulfate in aqueous media at various concentrations of ionic liquids and temperatures (288.15 K, 293.15 K, 298.15 K, 303.15 K, and 308.15 K). Critical micelle concentrations (CMCs) of the IL-surfactant systems obtained from conductivity measurement were found to be in good agreement with the CMC values of surface tension and UV–visible spectroscopy techniques. These CMCs values were used to calculate the thermodynamic parameters of IL-surfactant solutions such as standard free energy of micellization (ΔG°m), standard enthalpy of micellization (ΔH°m), and standard entropy of micellization (ΔS°m). Continuous decrease of the CMC values was observed with increasing concentrations of the ILs as well as temperatures. Packing parameters calculated from the surface tension measurement displayed small spherical shape for all the mixed micellar systems. Structural changes of the IL-surfactant solutions were also observed using FT-IR spectroscopic method. Increased positive inductive effect (+ I) of 2-alkyl substituent of the imidazolium cation of ionic liquid showed stabilizing effect on the micelle formation by lowering of more negative zeta potential values of the IL-surfactant systems. [ABSTRACT FROM AUTHOR]

The thermodynamics of protein–ligand interactions seems to be associated with a narrow range of Gibbs free energy. As a consequence, a linear enthalpy–entropy relationship showing an apparent enthalpy–entropy compensation (EEC) is frequently associated with protein–ligand interactions. When looking for the most negative values of ∆H to gain affinity, the entropy compensation gives rise to a barely noticeable increase in affinity, therefore negatively affecting the design and discovery of new and more efficient drugs capable of binding protein targets with a higher affinity. Originally attributed to experimental errors, compensation between ∆H and T∆S values is an observable fact, although its molecular origin has remained obscure and controversial. The thermodynamic parameters of a protein–ligand interaction can be interpreted in terms of the changes in molecular weak interactions as well as in vibrational, rotational, and translational energy levels. However, a molecular explanation to an EEC rendering a linear enthalpy–entropy relationship is still lacking. Herein, we show the results of a data search of ∆G values of 3025 protein–ligand interactions and 2558 "in vivo" ligand concentrations from the Protein Data Bank database and the Metabolome Database (2020). These results suggest that the EEC may be plausibly explained as a consequence of the narrow range of ∆G associated with protein–ligand interactions. The Gaussian distribution of the ∆G values matches very well with that of ligands. These results suggest the hypothesis that the set of ∆G values for the protein–ligand interactions is the result of the evolution of proteins. The conformation versatility of present proteins and the exchange of thousands (even millions) of minute amounts of energy with the environment may have functioned as a homeostatic mechanism to make the ∆G of proteins adaptive to changes in the availability of ligands and therefore achieve the maximum regulatory capacity of the protein function. Finally, plausible strategies to avoid the EEC consequences are suggested. [ABSTRACT FROM AUTHOR]

Dielectric studies of propionitrile (PPN) and butyronitrile (BTN) with 1,4-dioxane (DX) have been obtained at 25 °C temperature in the frequency range from 10 MHz to 30 GHz using the time-domain reflectometry method. The frequency-dependent complex permittivity spectra (CPS) of PPN and BTN with DX mixtures were fitted to the Harvilik-Nigami equation. The least squares fit method was used to determine the dielectric parameters of binary mixtures. The interaction of nitriles (PPN and BTN) with non-polar dioxane solvents through dipole–dipole and heteromolecular hydrogen bonding has been discussed using excess dielectric properties, thermodynamic parameters, Kirkwood correlation factor, and Bruggeman factor. These studies provide information on the intermolecular and intramolecular interactions between solutes and solvent molecules. [ABSTRACT FROM AUTHOR]

There is a growing need for an economical and efficient method capable of removing heavy metals from residual water. The current contribution aimed to evaluate the capacity of onion peel, an abundant agroindustrial waste product, to remove divalent cobalt (Co2+) from aqueous solutions. Onion peel was submitted to proximal chemical analysis, and various operational factors involved in biosorption were tested. The most suitable temperature (30 °C), pH (7.0), and biosorbent particle size (300–800 µm) were found. With an initial Co2+ concentration of 380 mg L−1, the maximum capacity of Co2+ removal was 59.88 mg g−1 in 120 min. The pseudo-second order and Langmuir models provided the best fit to the experimental kinetics and equilibrium of Co2+ biosorption, respectively. The thermodynamic study evidenced an exothermic, non-spontaneous, and favorable reaction (ΔH0 = −5.78 kJ mol−1; ΔS0 = −21.13 J mol−1 K−1), suggesting the formation of stable bonds in the biosorbent-Co2+ complex. The carbonyl and hydroxyl groups apparently play a fundamental role in Co2+ removal, and electrostatic attraction, ion exchange, and chemisorption are the principal mechanisms. Thus, the biosorption of Co2+ by onion peel has potential as an economical, eco-friendly, efficient, and sustainable treatment for wastewater. [ABSTRACT FROM AUTHOR]

The goal of the research was to examine the thermal degradation of pomegranate peel to determine its pyrolytic behavior for bio-energy generation. Initial characterizations (proximate analysis, ultimate analysis, biochemical analysis, and higher heating value) were performed before thermal deterioration to ensure that it was suitable for the pyrolysis process. Later, in a thermo-gravimetric analyzer with inert gas, thermo-gravimetric studies were carried out from ambient temperature to 1000 °C at three distinct heating rates (15, 20, and 25 °C/min). Thermo-gravimetric measurements revealed that the greatest devolatilization occurred between 200 and 540 °C. Four iso-conversional models (FWO, KAS, Tang, and Starink) were used for kinetic and thermodynamic analysis. The results revealed that the average activation energies were found 137.79, 149.63, 168.47, and 163.97 kJ/mol for FWO, KAS, Tang, and Starink model, respectively. The potential energy barrier (~ 4–8 kJ/mol) between activation energy and reaction enthalpy demonstrated favorable circumstances for product formation. Average Gibbs free energy change (∆G) for pomegranate peel by using iso-conversional FWO, KAS, Tang, and Starink model was found to be 81.84, 145.54, 80.53, and 80.83 kJ/mol, respectively. Thus, kinetic and thermodynamic data demonstrated that pomegranate peel had sufficient bioenergy potential. [ABSTRACT FROM AUTHOR]

Eutectic high-entropy alloys (EHEAs) have unique properties, making them a significant sub-branch of HEAs. Researchers are interested in their high strength, good castability, and ductility. However, due to the lack of a complete phase diagram database and previous research results, the traditional trial-and-error method will greatly reduce the research efficiency, and the composition design of EHEAs faces many difficulties. This paper summarizes the recent proposals of the thermo-dynamic factors that have a decisive role in the design of EHEAs. Regarding previous research, we discussed the methods for designing the main eutectic compositions currently used in research. These methods aid in developing novel approaches to fabricating EHEAs. [ABSTRACT FROM AUTHOR]

AbstractPlatinum-group cytostatic have been found in natural waters due to the current inefficiency of wastewaters treatment plants. This study was aimed to the assessment of inactive biomass of Aspergillus niger O-5 treated with cetyltrimethylammonium bromide as sorbent for solid phase extraction of [PtCl4]2-complex from aqueous dissolutions for the subsequent development of new water treatment technologies. Maximum sorption capacity of 54 mg·g−1 was achieved at 25 °C under the following experimental conditions: pH of dissolution = 5, biomass mass = 10 mg, dissolution volume = 10 mL, Pt(II) mass = 0.5 mg and contact time = 30 min. The good fitting of the model of Ho and the increase of sorption capacity up to 102 mg·g−1 with temperature suggested the chemisorption as predominant mechanism. The mean free energy of adsorption was higher than 8 kJ·mol−1 for all temperatures, which also indicated the chemical character of the interaction. The absolute value of the standard molar Gibbs free energy of formation increased from 3.032 to 8.336 kJ· mol−1 with temperature signifying that the sorption was thermodynamically favored, occurred spontaneously and the degree of spontaneity increased with temperature. The positive value (32.3 kJ·mol−1) of the standard molar enthalpy qualified the sorption as an endothermic process, after which the adsorbent/sorbate system became more thermodynamically stable. [ABSTRACT FROM AUTHOR]

This study aimed to measure both the solubility and thermodynamics of salicylic acid in binary solvent mixtures of (2-propanol + ethylene glycol) and (2-propanol + propylene glycol) at different temperatures in the range of 293.2–313.2 K. The experimental solubility data were analyzed using various linear and nonlinear cosolvency models, such as the van'tt Hoff, Jouyban-Acree, Jouyban-Acree-van'tt Hoff, mixture response surface and modified Wilson models and to evaluate the models, the mean relative deviations of the back-calculated solubility data were compared with experimental values. Through this analysis, the apparent thermodynamic parameters, including Gibbs energy, enthalpy, and entropy were calculated using the van'tt Hoff and Gibbs equations for this system. Additionally, the density values for salicylic acid saturated mixtures were also measured and represent mathematically using the Jouyban-Acree model. [ABSTRACT FROM AUTHOR]

Hybrid Layered Double Hydroxides (HLDH) are promising adsorption materials for water treatment due to their excellent anion exchange capacities, abundance of active sites, and eco-friendliness. HLDH was synthesized utilizing the co-precipitation technique in this work to demonstrate its applicability for the removal of direct sky-blue dye via an adsorption procedure. The effects of pH, dose, contact time, initial dye concentration, and temperature on the direct sky-blue dye adsorption efficiency were thoroughly investigated. The adsorbents were analyzed using scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), energy dispersive X-ray (EDX), and Brunauer–Emmett–Teller (BET). Under the best conditions, the maximum adsorption capacity has been achieved for Mg–Cr–Cl (42.95 mg/g) > Zn–Al–CO3 (39.76 mg/g) > Mg–Fe–Cl (38.08 mg/g). The adsorption of dyes on Mg–Cr–Cl, Zn–Al–CO3, and Mg–Fe–Cl followed a pseudo-second-order kinetic model and exhibited Langmuir-type monolayer adsorption. The influence of temperature was studied to determine the thermodynamic parameters. The estimated results showed spontaneous and exothermic adsorption processes. Electrolyte enhances the adsorption capacity to some extent, while surfactants block the sites, thus reducing the adsorption capacity. The maximum desorption of dye was influenced by the sodium hydroxide solution. The research described here might be utilized to create novel adsorbents with improved adsorption capacities for preserving the aquatic environment. [ABSTRACT FROM AUTHOR]

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

A new nine-principal cation high-entropy oxide of (Y 1/9 La 1/9 Nd 1/9 Sm 1/9 Yb 1/9 Lu 1/9 Eu 1/9 Gd 1/9 Ce 1/9) 2 O 3 (9HEO) was synthesized by co-precipitation method combined with conventional sintering at 1600 °C for 10 h. Two samples of 9HEO-(Ce3+) and 9HEO-(Ce4+) were obtained by adjusting the valence state of Ce element in 9HEO. The ratio of Ce3+ to Ce4+ in 9HEO-(Ce3+) and 9HEO-(Ce4+) is approximately 2:1 and 14:15, respectively. These two samples have the same bixbyite structure and similar microscopic morphology. Their relative density, thermal expansion coefficient, hardness and Young's modulus are close. The higher ratio of Ce3+/Ce4+ in 9HEO-(Ce3+) leads to the expansion of its lattice volume and the decrease of thermal conductivity (κ) compared with 9HEO-(Ce4+). In addition, the κ values of these two samples are lower than those of Y 2 O 3 and (Eu 0.2 Er 0.2 Lu 0.2 Y 0.2 Yb 0.2) 2 O 3 , which have a bixbyite structure and lower entropy. 9HEO-(Ce3+) and 9HEO-(Ce4+) show higher oxygen barrier property compared with Y 2 O 3 -stabilised ZrO 2. [ABSTRACT FROM AUTHOR]

The aim of this study is to purify industrial textile effluents by treating two types of commonly encountered dyes: blue maxilon (BM), of cationic nature, and black eriochrome (NE), of anionic nature. We intend to employ an innovative approach based on the adsorption of these dyes onto a novel vegetal biomaterial derived from Aleppo pine fibers (FPAs). A kinetic and thermodynamic study was conducted. The effect of some physicochemical parameters on both dye adsorption and FPAs was also evaluated. The modeling of the adsorption results was performed using Langmuir, Freundlich, Temkin, and Dubinin Radushkevich (D-R) isotherms. The results indicate that the equilibrium time strongly depends on the initial concentration of the two dyes, being 60 min with pseudo-second-order adsorption kinetics for both dyes. Adsorption isotherms under the optimal conditions of adsorbent mass, temperature, medium pH, and dye concentration were used to determine the maximum adsorption efficiency, which was close to 93% and 98% for BM and NE, respectively. The results also show that the adsorption of both dyes on FPAs fits well with Langmuir's model. The thermodynamic study indicates that the adsorption of both dyes on FPAs is spontaneous and exothermic in nature for BM and endothermic for NE. [ABSTRACT FROM AUTHOR]

In this study, we examined biodegradable packaging made from cassava starch and tomato peel and seed. We evaluated biodegradation using fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG) and visual analysis. Water sorption isotherms and thermodynamic properties were analyzed at various temperatures (5 °C, 15 °C and 25 °C) and humidity levels until reaching constant weight. These packages biodegrade rapidly, typically within about 18 days, in contrast to conventional fossil-based polymer packaging. During degradation, we observed visible surface changes, including roughness, hole formation, fragmentation and color alterations, confirmed by FTIR, TG and Scanning Electron Microscopy analyses. Water solubility decreased with the addition of tomato peel. The Guggenheim-Anderson-de Boer model provided the best fit for the water sorption isotherm data. Monolayer moisture content (Xm) ranged from 11.02 to 7.54 g of H2O/100 g of solids at 5 °C, from 12.99 to 8.89 g of H2O/100 g of solids at 15 °C, and from 34.93 to 16.68 g of H2O/100 g of solids at 25 °C. Thermodynamic properties revealed that lower moisture content led to higher ∆Hdiff values, indicating more active sorption sites, and higher − ∆Sdiff values, suggesting greater order in sorbed water molecules. In conclusion, our results highlight the viability of these active biodegradable packages, which degrade rapidly and exhibit adsorption behavior primarily influenced by entropy, as an environmentally friendly alternative. [ABSTRACT FROM AUTHOR]

The use of surfactants in oil recovery can effectively improve crude oil recovery rate. Due to the enhanced salt and temperature resistance of surfactant molecules by non-ionic chain segments, anionic groups have good emulsifying stability. Currently, there are many studies on anionic non-ionic surfactants for oil recovery in China, but there is relatively little systematic research on introducing EOs into hydrophobic alkyl chains, especially on their self-assembly behavior. This article proposes a simple and effective synthesis method, using 3-aminopropane sulfonic acid, fatty alcohol polyoxyethylene ether, and epichlorohydrin as raw materials, to insert EO into hydrophobic alkyl chains and synthesize a series of new anionic non-ionic Gemini surfactants (CnEO-5, n = 8, 12, 16). The surface activity, thermodynamic properties, and self-assembly behavior of these surfactants were systematically studied through surface tension, conductivity, steady-state fluorescence probes, transmission electron microscopy, and molecular dynamics simulations. The surface tension test results show that CnEO-5 has high surface activity and is higher than traditional single chain surfactants and structurally similar anionic non-ionic Gemini surfactants. Additionally, thermodynamic parameters (e.g., ΔG°mic ΔH°mic ΔS°mic et al. indicate that CnEO-5 molecules are exothermic and spontaneous during the micellization process. DLS, p-values, and TEM results indicate that anionic non-ionic Gemini surfactants with shorter hydrophobic chains (such as C8EO-5) tend to form larger vesicles in aqueous solutions, which are formed in a tail to tail and staggered manner; Negative non-ionic Gemini surfactants with longer hydrophobic chains (such as C12EO-5, C16EO-5) tend to form small micelles. The test results indicate that CnEO-5 anionic non-ionic Gemini surfactants have certain application prospects in improving crude oil recovery. [ABSTRACT FROM AUTHOR]

We have undertaken an ab initio investigation of emerging metal lead-free halide double perovskite materials for renewable energy applications using the WIEN2k simulation code. These materials have garnered significant attention from the research community due to their potential utility in electronic devices. Through an analysis of their electronic structure, we have ascertained that these materials exhibit characteristics of direct band gap semiconductors, falling within the energy range spanning 0.755 to 1.825eV. Furthermore, to check their suitability for use in photovoltaic devices, optical properties have been investigated. The thermoelectric potential of these materials has been explored using the BoltzTraP simulation code. The study of thermoelectric parameters indicates that the studied materials are effective thermoelectric materials with a strong potential for n-type doping. Additionally, thermodynamic parameters have been investigated to check their thermal stability, required to make them promising candidates for a wide range of renewable energy applications. [ABSTRACT FROM AUTHOR]

In the current work, the solubility of amlodipine besylate (ADB) was studied in the ethylene glycol + ethanol at different temperatures (293.2-313.2 K). The experimental solubility data obtained herein were correlated with some well-known cosolvency models and the accuracy of these models was investigated with the mean relative deviations of the back calculated data. The apparent thermodynamic parameters (Gibbs energy, enthalpy and entropy) of ADB in the non-aqueous saturated mixtures were also calculated with the van't Hoff and Gibbs equations at Thm. [ABSTRACT FROM AUTHOR]

The effect of temperature on the stability of anthocyanin extract from aronia as pigment and ascorbic acid as copigment was evaluated. Different temperatures and copigment concentrations were used for the investigation of pigment:copigment interaction. Equilibrium constant of copigmentation process was determined. Thermodynamic parameters such as ΔG, ΔH, ΔS were calculated. At high temperatures, around 60oC destruction was observed. This is confirmation for the reversibility of the copigmentation process. [ABSTRACT FROM AUTHOR]

Recently, the three independent papers cited in the title were published in this journal, dealing with the sorption of cationic dyes on specially prepared solid sorbents. Although kinetics, isotherm and thermodynamics are three important components for the correct description of any sorption process, the authors of these original papers introduced several fundamental errors in these parts. Therefore, we present detailed analyses of these errors in the hope that this "Comment" paper will also be useful to other researchers (especially early career researchers) to avoid replicating such errors elsewhere in the future. Recently, three independent papers were published in this journal by Tan et al. (2023), Saeed et al. (2023), and Yıldız et al. (2023), all dealing with the sorption of cationic dyes on specially prepared solid sorbents. Although kinetics, isotherm and thermodynamics are important components for the correct description of any sorption process, several fundamental errors and inconsistencies have been identified. Therefore, we present detailed analyses of these errors in the hope that this paper will also be useful to other researchers (especially early career researchers) to avoid replicating such errors elsewhere in the future. Furthermore, the present authors emphasize that this paper is not intended to discredit the subject of the considered experimental studies, and they hope that these comments will be read in the spirit in which they are intended, i.e. as constructive criticism to produce better final scientific papers. [ABSTRACT FROM AUTHOR]