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A theoretical study of magnetic, electronic structure, mechanical and thermodynamic properties of Cr2TaZ (Z = Al, Ga and Sb) Heusler alloys has been extensively investigated by the full-potential linearized augmented plane wave (FP-LAPW) method with the Generalized Gradient Approximation (GGA). Structural parameters such as lattice constant (a) , bulk modulus (B) and first pressure derivative of bulk modulus (B ,) were obtained by using the Murnaghan equation. The calculated lattice constants for Cr2TaAl, Cr2TaGa and Cr2TaSb alloys are for 61,029, 61,170 and 60,795 Å, respectively. It is found that the L21-type (AlCu2Mnl-type) structure is energetically more stable than the X-type (CuHg2Ti-type) structure due to the lower total energy. The results of elastic constants robustness show that the mechanical stability of Cr2TaZ (Z = Al, Ga and Sb) can be well-maintained. The calculated electronic band structure reveals the metallic nature of Cr2TaZ (Z = Al, Ga and Sb) and its total magnetic moment of 2.00 μ B is mainly contributed by Cr atom from strong spin splitting effect, as indicated with the distinctive distributions of the density of states in two spin directions. Furthermore temperature and pressure dependence of thermodynamic properties of these materials have been examined in the ranges (0–1400 K) and (0–25 GPa), respectively. [ABSTRACT FROM AUTHOR]

Double perovskites (DPs) have gained the interest of researchers due to their unique properties. In present work, structural, mechanical, electronic, and thermodynamic properties of Rb2XIO6 (X = Ga, In) DPs are investigated using first‐principles calculations. The tolerance and octahedral factors are calculated in the allowed range of DPs. The phonons dispersion curves were computed with positive frequencies. The elastic constants prove the mechanical stability. Mechanical properties explore the anisotropic, brittle, and stiffer nature of both DPs. The computed band structures discover the metallic nature, where O–p and I–s states are found to cross the Fermi level. Debye temperature for Rb2GaIO6 is calculated higher than Rb2InIO6. Grüneisen parameter is evaluated to decrease with increasing pressure and temperature. Specific heat capacity is observed to saturate at 450 K. The coefficient of thermal expansion are calculated as 9 × $\times \textrm{ }$ 10−5 and 8.95 ×$\times$ 10−5 K−1 at 1000 K for Rb2GaIO6 and Rb2InIO6, respectively. [ABSTRACT FROM AUTHOR]

Despite many years of research and continuous improvements in scientific equipment, some of the thermodynamic properties of binary systems are still unknown, or are only theoretically predicted or calculated. This situation often arises from the difficulties in preparing alloys for experimental measurements. The alloys from the Mg-Pd system, especially for the Pd-rich side, are difficult to produce, and the availability of thermodynamic data is very limited. Therefore, this paper presents calorimetric studies on the standard enthalpy of formation of alloys from the Mg-Pd system, which were prepared using mechanical alloying. Three alloys (S1, S2, and S3) were synthesized, homogenized, and subjected to X-ray diffraction (XRD) analysis to investigate their phase composition. The XRD studies showed that the alloys designated as S1 and S2 were the intermetallic phases Mg6Pd and Mg0.9Pd1.1, and the S3 sample was a mixture of MgPd and MgPd3 intermetallic phases. Their heat effects, measured by drop calorimetry, were used to calculate the values of the standard enthalpies of formation of the prepared phases. The values obtained were as follows: −27.5 ± 1.1 kJ/mol at. for the Mg6Pd intermetallic phase, −72.7 ± 1.0 kJ/mol at. for the Mg0.9Pd1.1 intermetallic phase, and −46.8 ± 1.5 kJ/mol at. for the alloy which was a mixture of MgPd and MgPd3. These data were compared with values from the existing literature on the enthalpy of formation of alloys, as well as with data calculated using Miedema's model. [ABSTRACT FROM AUTHOR]

Liquid metals and metallic alloys often exist as metastable phases or can be undercooled below their equilibrium melting point. The Traditional CALPHAD (CALculation of PHAse Diagrams) approach struggles to accurately model these metastable conditions, which are important in rapid quenching techniques like additive manufacturing, and to understand glass formation or oxidation phenomena occurring in the liquid phase during nuclear and high-temperature aerospace applications. On the contrary, the third-generation CALPHAD models have the potential to accurately describe metastable phase diagrams to provide better predictions of molten phase behavior under non-equilibrium conditions. The latter approach is utilized in this study to achieve a more accurate description of the thermodynamic properties of elemental Nb and Zr, with a particular focus on their liquid phases. By incorporating available first-principles data, the representation of the liquid state is improved for both elements, capturing the peculiar behavior of the heat capacity in a wide temperature range. These improvements enable a more reliable prediction of phase stability and liquidus boundaries in the Nb-Zr system. A partial re-assessment of the Nb-Zr binary phase diagram is also conducted with refined predictions of liquidus boundaries that align well with experimental data. [ABSTRACT FROM AUTHOR]

In the present study, density, viscosity, surface tension, and refractive indices of binary mixtures of biodiesel + diethyl ether (DEE), diethylene glycol dimethyl ether (DEGDME), and dimethyl carbonate (DMC), which are used as biodiesel additives, have been measured over the whole range of concentration from 288.15 to 323.15 K and at atmospheric pressure. The density and kinematic viscosity values of the binary mixtures, prepared with different mole fractions of DEE, DEGDME, and DMC, were compared with the limits specified by the biodiesel fuel standard (EN14214). Furthermore, experimentally measured density values were utilized to define a first-order polynomial equation for estimating the densities of the prepared binary mixtures. Excess molar volumes (VE), excess thermal expansion coefficient (αpE), excess Gibbs energy of activation of the viscous flow (∆G*E), deviations in kinematic viscosity (Δν), surface tension (Δσ), and refractive index (ΔnD) values were calculated. These deviation values from ideality were adjusted to a Redlich–Kister (R–K) polynomial equation and the obtained coefficients in the equation were reported. VE values were negative for biodiesel + DEE while positive values were obtained for biodiesel + DEGDME and DMC. Moreover, the values of Δν were negative for all mixtures of biodiesel + DEE, DEGDME, and DMC. The obtained results were analyzed with regard to intermolecular interactions and structural effects between both similar and dissimilar molecules. [ABSTRACT FROM AUTHOR]

Valeramide and halogenated phenol in solvent benzene have been studied using DFT. Dielectric relaxation studies have also been undertaken. The wave functional characteristics like reduced density gradient (RDG), electron localization function (ELF), localized orbital locator (LOL) are also evaluated. It has been found that the computed FMO energies accurately depict the characteristics of electron excitation which provide an explanation for the charge transfer. MEP analysis is done to identify electrophilic and nucleophilic sites. The theoretical analysis of the UV-Visible spectrum using the TD-DFT method in solution and the computational investigation of spectroscopic wavenumbers was also carried out (IR, Raman). Thermodynamic properties of title compound at different temperatures was carried out. Various dielectric parameters, like the dielectric constant ε ′ , the dielectric loss ε ″ at microwave frequency, the static dielectric constant ε0 and the dielectric constant ε∞ at optical frequency, were measured across five distinct molar ratios (i.e. 1:3, 1:2, 1:1, 2:1 and 3:1). While the relaxation time τ2 for group rotation is utilized to identify the steric interaction of the proton donor, Higasi's single-frequency equation is proven to measure multiple relaxation time τ1 to determine the intensity of hydrogen bonding. At a 1:1 (molar ratio), the values of relaxation time were found to be high. Molecular docking was done in a supplementary effort to support intermolecular interactions. [ABSTRACT FROM AUTHOR]

CuCrZr alloy is widely used in vacuum circuit breaker contact materials and high‐speed railroad contact wires, etc. The study of the effect of different Cr and Zr contents on the performance of CuCrZr alloy is of great significance for the improvement of circuit breaker's breaking capacity, as well as the load and structural stability under harsh working conditions. In this paper, the mechanical properties, electronic density of states and thermodynamic properties of CuCrZr solid solution alloys randomly doped by different concentrations of Cr and Zr are comparatively analyzed using first‐principles calculations based on density functional theory. The results show that the alloys with different doping compositions have strong mechanical stability, electrical conductivity, and thermomechanical stability, and the reduction of the Cr/Zr doping concentration ratio can improve the toughness and ductility of the alloys, and the solid solution alloy with the composition of CuCr0.06Zr0.19 has the best machinability. The doping of Cr and Zr can improve the thermal stability of the alloy, Cr and Zr can be used as high‐temperature toughening elements for Cu. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

For thermosetting resins the degree of cross-linking plays a crucial role in the dielectric properties of the resin. In our previous works we confirmed this by simulating the relationship between the dielectric properties of poly(2-(4-benzocyclobutenyl)-divinylbenzene (DVB-S-BCB)) and the degree of cross-linking. In our research described here, we constructed a novel random copolymer with all-hydrocarbon structure based on poly(DVB-S-BCB) by introducing styrene (St) as the second polymerization monomer, thus controlling the number of cross-linking sites in the polymer. The effect of changes in St monomer content (number of cross-linking points) in the polymer chains, i.e. DVB-S-BCB and St, on the dielectric properties of the cured resins was investigated by molecular dynamics simulations. The simulation results showed that increasing the St monomer content in the copolymer, decreasing the cross-linking points, led to an increase in the dielectric constant of the cured resin, in addition to which the copolymer exhibited excellent thermo-mechanical properties. We also tested resin samples prepared by the experimental method and compared them with the simulated data, confirming the reliability of the results within acceptable error limits. [ABSTRACT FROM AUTHOR]

In hydrogen liquefaction process,precooling cycle is an important link,among which the unit energy consumption of MR is relatively low,so it is particularly important to optimize the performance of MR.In this paper,the experimental system of VLE was built by the method of single-phase liquid phase cycle,and the properties of VLE in the ternary system R290+R600a+N2were studied.The temperature range of 273.15 K～323.15 K was used to study the ternary mixing medium R290+R600a+N2,and 18 groups of experimental data were obtained.At the same time,Peng-Pobinson-Stryjek-Vera （PRSV） equation of state combined with van der Waals（vdW） mixing rule was used to calculate the VLE properties of the ternary system.By comparing the experimental data with the calculated results,the average absolute relative deviation AARDp of the system pressure is 0.85%,and the average absolute deviation AADy1,AADy2and AADy3of the system components R290,R600a and N2are 0.0064,0.0027 and 0.0063,respectively. [ABSTRACT FROM AUTHOR]

To assess the performance of potential refrigerant-absorbent pairs, it is essential to have thermodynamic properties of both the pure components and their mixtures. Since these mixtures do not behave ideally, the properties of the solutions can only be obtained through experimental means. This paper's proposed candidate pair is the environmentally friendly refrigerant 2,3,3,3-Tetrafluoropropene (R1234yf) and the organic solvent Dimethylacetamide (DMAC). For this purpose, an experimental setup was designed to obtain data at the equilibrium point between the gas and liquid phases. The collected data was analyzed using models based on the vapor-liquid equilibrium of mixtures. Correlations were established for pressure-temperature and refrigerant concentration in the liquid phase and the solution's enthalpy. These results can facilitate further investigations into the solution's compatibility as an alternative working pair. [ABSTRACT FROM AUTHOR]

Agricultural residues have a high potential to be transformed and utilized into new products through convective drying. In this study, the effects of drying temperature (50, 60, and 70 °C) on kinetic monitoring and mathematical modeling, physical properties, total phenolic compounds, antioxidant activity (ABTS, DPPH, and FRAP), in vitro digestibility, and structural properties of broccoli residues (leaves) were investigated. The analyzed data revealed that the Midilli model adequately fitted the drying data with maximum R2 values (99.74%), minimum mean square error (MSE) (< 0.0020) and chi-square ( χ 2 ) (< 0.0001). Additionally, increasing the drying temperature (50–70 °C) reduced the drying time to 240 min and increased the effective diffusivity (7.25 × 10–10 m2 s−1). The activation energy was estimated at 27.06 kJ mol−1 and thermodynamic properties indicated that the process did not occur spontaneously. Temperature also had a significant effect (p < 0.05) on the physical properties of broccoli leaf powder (BLP), as well as on the total phenolic compound content (185.69–273.81 mg GAE/100 g), antioxidant activity (6.29–12.72 µM TE/g), and bioaccessibility (8.42–14.10%), with the highest contents observed at 50 °C. Finally, structural properties classified BLP as amorphous with preserved primary structures. These findings help to understand the drying behavior of broccoli leaves while promoting practices for recycling agro-food residues. [ABSTRACT FROM AUTHOR]

In this article, we have conducted a comprehensive study on the structural, mechanical, electronic, magnetic and thermodynamic properties of the Heusler alloys FeZrTiZ ( Z = A l , G a , G e ). Our investigation utilize the GGA exchange correlational approximation functional. The results of our analysis indicate that among the Y1-, Y2- and Y3-type structures, the Y1-type structure exhibits stability and demonstrates ferromagnetic behavior. Furthermore, mechanical property analysis reveals that all alloys possess ductile characteristics. The analysis of the density of states of the Heusler alloys FeZrTiZ ( Z = A l , G a , G e ) demonstrates the presence of half-metallic nature in all of the alloys. Additionally, the investigated Heusler alloys exhibit integer spin magnetic moments. To study thermodynamic properties, we use quasi-harmonic approximation, which allows to analyze specific heat capacity, thermal expansion, Debye temperature, vibrational free energy, internal energy and entropy of the Heusler alloys FeZrTiZ ( Z = A l , G a , G e ). Overall, our findings provide a clear understanding of the structural, mechanical, electronic, magnetic and thermodynamic characteristics of Heusler alloys FeZrTiZ ( Z = A l , G a , G e ), shedding light on their potential applications in spintronics. [ABSTRACT FROM AUTHOR]

The effect of polaron on the thermodynamic properties of an asymmetric semiconductor quantum wire (ASCQW) in the presence of magnetic field is investigated. Both Lee–Low–Pines (LLP) approach and canonical ensemble theory (CET) are used in order to perform complete free energy spectrum on the one hand and derive thermodynamic parameters including internal and free energies, entropy, heat capacity, Magnetization and magnetic susceptibility on the other hand. It is shown that both Electron-Longitudinal-Optical (ELO) phonon coupling and magnetic effects modified considerably the thermodynamic properties of an ASCQW. Whatever the asymmetric quantum wire value, there is a critical value of the magnetic field ( B ≈ 0.4 mT ) which conducts to the maximum value of the heat capacity. For the given value of the magnetic field, the system stores the most energy, as particles are in the maximum thermal agitation range. In the presence of the magnetic field, entropy is a decreasing function of ELO phonon interaction. Energy, magnetization and magnetic susceptibility increase with magnetic field intensity. Thus, the magnetic field plays a role of confining parameter, which increases the stability of polaronic entities in low-dimensional ASCQW. The thermodynamic properties of the ASCQW are more affected with very high intensity of the magnetic field and low ELO phonon coupling. [ABSTRACT FROM AUTHOR]

This work investigated the influence of Ti and Nb interchangeability on the hydrogen sorption properties of the Ti x Nb 80-x Al 10 Cr 10 (x = 30, 40, and 50) multicomponent system. The CALPHAD method was successfully employed to design body-centered cubic (BCC) solid solutions. These alloys absorb hydrogen at room temperature, achieving a hydrogen-to-metal ratio of about 1.7. Pressure-Composition-Temperature diagram measurements demonstrated that increasing Ti content at the expense of Nb led to increased stability of the metal hydrides. DFT calculations of the pure elements and binary hydrides of the Ti–Nb–Al–Cr system were carried out, and the lattice parameters of the BCC alloy and FCC hydride and the enthalpy of hydride formation were estimated by applying an ideal mixing rule. The calculated and experimental results showed satisfactory agreement, indicating that the theoretical approach can be used to estimate the structural and thermodynamic parameters of alloys and hydrides of the Ti x Nb 80-x Al 10 Cr 10 system. [Display omitted] • The single-phase BCC Ti x Nb 80-x Al 10 Cr 10 (x = 30, 40, and 50) alloys were designed. • Increasing Ti content at the expense of Nb increases the stability of the hydrides. • The hydride stability is not directly correlated with the lattice volume of the host metal. • DFT and the mixture rule were employed to predict structural and thermodynamic parameters. [ABSTRACT FROM AUTHOR]

Sulfamerazine (SMR) is a drug used as an antibacterial agent in the treatment of some pathologies, such as bronchitis, prostatitis and urinary tract infections. Although this drug was developed in 1945 and, due to its toxicity, was partially displaced by penicillin, due to the current problem of bacterial resistance, compounds such as SMR have regained validity. In this context, the thermodynamic study of SMR in cosolvent mixtures of acetonitrile (MeCN) + ethanol (EtOH) at nine temperatures (278.15–318.15 K) is presented. The solubility of SMR was determined by UV–Vis spectrophotometry, following the guidelines of the shake-flask method. The solubility process was endothermic in all cases; thus, the minimum solubility was reached in pure EtOH at 278.15 K, and the maximum solubility was reached in pure MeCN at 318.15 K. Both the solution process and the mixing process were entropy-driven. On the other hand, the solubility data were modeled by using the van't Hoff–Yalkowsky–Roseman model, obtaining an overall average relative deviation of 3.9%. In general terms, it can be concluded that the solution process of SMR in {MeCN (1) + EtOH (2)} mixtures is thermodependent, favored by the entropy of the solution and mixture; additionally, the van't Hoff–Yalkowsky–Roseman model allows very good approximations to be obtained and is a simple model that starts from only four experimental data. [ABSTRACT FROM AUTHOR]

Transparent conducting oxides (TCOs) from the semiconductor family have garnered considerable interest due to the growing popularity of optoelectronic and thermodynamical applications. Our present study has presented findings on the electronic, optical, and thermodynamic characteristics of spinel oxide MnGa2P3H4NO14; using density functional theory (DFT), we utilized first‐principles calculations carried out with the Wien 2 k software package. The calculations were performed using the generalized‐gradient‐approximation plus Hubbard potential U (GGA+U) method for the doped materials. The band structure calculation reveals that the parent compound exhibits a semiconducting nature and a direct band gap of 2.9 and 1.7 eV for spin‐up and down channels, respectively. The stability of the material is assessed by evaluating its formation energies, which reveal that spinel oxide exhibits the highest stability. The thermodynamic properties are determined using the quasiharmonic Debye model, implemented in the GIBBS 2 code. Furthermore, the quasiharmonic Debye model examines the pressure and temperature dependence of all parameters related to the investigated spinel oxides. In order to evaluate the effectiveness of the radiation shielding, we computed the mass attenuation coefficient for the XCOM program that was investigated from the sample. In addition, linear attenuation, half‐value layer, and mean free path values have been evaluated. A thorough investigation into the dielectric function's optical characteristics was conducted. It has been found that the dielectric function exhibits a wide range of energy transparency. The discovery of UV‐absorbing materials with extremely narrow band gaps suggests their potential use in optoelectronic and solar cell applications. These results provide solid proof and motivation for seeking cutting‐edge optoelectronic materials and technology. [ABSTRACT FROM AUTHOR]

With the development of new energy vehicles, there is a growing demand for automotive interior materials that meet higher standards. In this case, thermoplastic elastomer (TPE), being a completely recyclable environment‐friendly polymer material, possesses advantages such as plasticizers and solvents free, excellent mechanical properties, less volatile organic compounds (VOC) release and low processing cost compared with polyvinyl chloride (PVC), polyurethane (PU), and thermoplastic polyolefin (TPO) skins, become a desirable choice for automotive injection molding automotive skin. Hence, this work investigates the influence of hydrogenated styrene‐butadiene‐styrene block copolymer (SEBS) molecular weight, chemical structure, and polypropylene (PP) doping amount on thermodynamic, crystallinity, rheological, and mechanical properties of TPE, which provides a scientific basis for guiding the material selection of TPE injection molding skin. [ABSTRACT FROM AUTHOR]

Today, hydrogen is one of the most credible options for a non-polluting, carbon-free energy carrier. Hydrogen can be obtained or produced by different means from different renewable energy sources and can be stored in solid, liquid, or gaseous form. Storing hydrogen in complex hydrides in solid form is one of the most efficient methods of storage because they are secure, offer high hydrogen capacity, and demand optimal functioning conditions. Complex hydrides give a large gravimetric capacity that allows large amounts of hydrogen to be stored. This study examined the effects of triaxial strains on hydrogen storage properties of the perovskite-type compound K2NaAlH6. The analysis was conducted through first principle calculations using the full potential linearized augmented plane wave (FP-LAPW) approach. Our results indicate that the formation energy and desorption temperature of K2NaAlH6 hydride were improved under a maximum triaxial compressive strains of ε ≈ − 5%. Specifically, the values of formation energy and desorption temperature were − 40.14 kJ/mol.H2 and 308.72 K, respectively, compared to the original values of − 62.98 kJ/mol.H2 and 484.52 K. In addition, the analysis of the densities of states showed that changes in the dehydrogenation and structural properties of K2NaAlH6 were closely linked to the Fermi level value of the total densities of states. These findings provide valuable insights into the potential of K2NaAlH6 as a hydrogen storage material. [ABSTRACT FROM AUTHOR]

Following the path integral approach and within in the context of nonrelativistic Snyder–de Sitter algebra, we formulate the Green function for Dirac oscillator particle in (1 + 1) space-time dimension. Using the momentum space representation | p , p 0 〉 , we determine the energy eigenvalues and the eigenfunctions, where the wave functions can be given in terms of Gegenbauer polynomials. In addition, the high-temperature thermodynamic properties of the relativistic harmonic oscillators are analyzed, which we found that the heat capacity is not equal two times greater than the heat capacity of the one-dimensional harmonic oscillator for higher temperatures in SdS model. The special cases are found and discussed. [ABSTRACT FROM AUTHOR]

The structural, dynamical, and thermodynamic properties of zinc‐blende (ZB) mercury selenide (HgSe) and cadmium selenide (CdSe) were systematically explored using an ab initio pseudopotential approach based on the density functional theory (DFT). The optimized lattice constants are in excellent agreement with the available experimental and theoretical results. The electronic properties show semiconducting behavior with a direct bandgap of 0 and 0.36 eV for HgSe and CdSe, respectively. Also, using the linear response approach, the detailed vibration properties of HgSe and CdSe are obtained. According to the calculated phonon dispersion, it is concluded that HgSe and CdSe are dynamically stable in the ground state; several peculiarities in the dispersion curves of these materials are generally similar, but the zone‐boundary frequencies and zone‐center optical frequencies of HgSe are lower than those of CdSe. The phonon frequencies at the high‐symmetry points Γ, X, and L for HgSe and CdSe are in good agreement with the other theoretical reported. On the other hand, the dielectric properties are investigated and discussed. The results show that the dielectric tensor is diagonal, and the Born effective charge tensor is also isotropic. Finally, based on the lattice dynamical properties, we investigate the thermodynamic properties of both compounds, such as Helmholtz free energy F, internal energy E, entropy S, and specific heat Cv. The results show that HgSe and CdSe exhibit similar but slightly different behaviors in terms of its thermodynamic properties, which is expected because the atoms Hg and Cd are in the same group and exhibit a different atom mass. Most of the results presented in this study are novel and should provide a useful reference for future studies. [ABSTRACT FROM AUTHOR]

The fascinating characteristics, such as straightforward and stable crystal structure, and double perovskites are currently popular materials for applications in renewable energy. In our study, we applied CASTEP and DFT, called density functional theory, to theoretically investigate the mechanical, optical, and thermoelectric characteristics of cubic Rb 2 TlCoF 6. Calculations of the compound Rb 2 TlCoF 6 's structural, electrical, optical, mechanical, and thermodynamic properties are made using the GGA-PBE exchange correlational functional and the Fm3m with space group no.225 vol and compound lattice constant are 9.08 Å and 748.613 Å3, respectively. For Rb 2 TlCoF 6 , the measured energy band gaps are 1.45 eV. The mechanical and elastic constants are calculated to confirm the ductile properties of Rb 2 TlCoF 6. The brittle characteristics have been verified using Passion and Pugh's ratios, which are 1.67 and 0.25, according to elastic constants. Vickers compound hardness H v and anisotropy factor "A" are 4.19 and 0.77, respectively. The compounds' optical characteristics reveal significant conductivity and absorption. The compound exhibits high-efficiency photocatalytic activity based on its optical characteristics. Based on mechanical stability, such as Debye temperature, melting temperature, minimum thermal conductivity, average sound velocity, free energy, and other variables, the thermodynamic and structural stabilities are calculated. These materials controlled electrical and other properties make them potentially useful in photocatalytic applications. According to the outcomes, Rb 2 TlCoF 6 is appropriate for photocatalytic water-splitting applications and water deterioration. • To utilize Density Functional Theory (DFT) with mBJ and GGA-PBE methods. • The elastic constants values show that Rb 2 TlCoF 6 is mechanically stable. • The density of state calculations indicates semiconductor. • Studied materials are most suitable for photocatalytic for water splitting applications. [ABSTRACT FROM AUTHOR]

Cyclic alcohols are commonly found in natural and synthetic products and are involved in many biological processes. An ability to model their thermodynamic properties is of interest in food, flavouring, and pharmaceutical manufacturing, particularly for mixtures for which available experimental data are limited. Good examples are mixtures including menthol, a naturally occurring cyclic alcohol widely used in the food and pharmaceutical industries, well-known for its cooling-sensation properties and its role in the discovery of the TRPM8 receptor. Here, we extend the SAFT-γ Mie group-contribution method to model cyclic alcohols, by introducing a new cCHOH group (c for cyclic) composed of two identical Mie segments. Three association sites (two electronic sites of type e and one hydrogen site of type H) are also included to mediate hydrogen bonding. New parameters that characterise the group interactions (one new like interaction and 26 new unlike interactions) are developed and are employed to determine the thermophysical properties (vapour pressure, saturation density, vaporisation enthalpy, and second-order thermodynamic derivative properties) of pure cyclic alcohols, and mixture properties (vapour–liquid equilibria, liquid–liquid equilibria, solid–liquid equilibria, density, and excess enthalpy) of cyclic alcohols in several solvents. The quality of the model is evaluated by comparing predictive calculations with experimental data of 76 systems: six pure fluids and 70 binary mixtures, selected from a large range of solvent families: cyclic, linear, and branched alkanes, 1-alcohols, 2-alcohols, 2-ketones, esters, aromatic compounds, water, and carbon dioxide. Very good overall agreement is found, including for the prediction of solid–liquid solubility, which confirms the transferability of the new group parameters. Together with previously developed parameters, these open the way for the prediction of the thermodynamic properties of further complex mixtures. [ABSTRACT FROM AUTHOR]

The use of next-generation refrigerant fluids is preferred to improve the global environment's livability. In this context, the thermodynamic properties of R466A, a new-generation refrigerant with low ozone depletion potential and global warming potential, have been modelled using various methods. Linear regression, artificial neural network (ANN), and gene expression programming (GEP) models were used to predict R466A's temperature–pressure relationship in the saturated liquid–vapor phase and its enthalpy-entropy relationship in the superheated vapor phase. The models' performance was evaluated based on statistical parameters such as the determination coefficient (R2), mean absolute error, and root mean square error (RMSE), and compared with actual values. The research results indicate that the GEP model achieved the lowest RMSE values for predicting thermodynamic properties in the saturated vapor phase. On the other hand, ANN models were found to be more suitable for estimating properties in the superheated vapor phase. The R2 values for ANN models ranged from 0.999 to 0.986, whereas GEP models exhibited R2 values between 0.999 and 0.982. Despite slightly lower performance compared to some ANN models, GEP models employed explicit equations. [ABSTRACT FROM AUTHOR]

Pyrazinamide is a first line drug used for the treatment of tuberculosis, a pathology that caused the death of more than 1.3 million people in the world during 2022, according to WHO, being a drug of current interest due to its relevance in pharmaceutical and medical sciences. In this context, solubility is one of the most important physicochemical parameters in the development and/or optimization of new pharmaceutical forms, so the present work aims to present a thermodynamic study of the solubility of pyrazinamide in nine organic solvents of pharmaceutical interest. Using the shake-flask method and UV/Vis spectrophotometry, the solubility of this drug was determined at 9 temperatures; the maximum solubility was obtained in dimethyl sulfoxide at 318.15 K ( x 2 = 0.0816 ± 0.004 ) and the minimum in cyclohexane at 283.15 K ( 1.73 ± 0.05 × 10 − 5 ). From the apparent solubility data, the thermodynamic functions of solution and mixing were calculated, indicating an endothermic process. In addition, the solubility parameter of pyrazinamide was calculated using the Hoftyzer-van Krevelen (32.90 MPa1/2) and Bustamante (28.14 MPa1/2) methods. The maximum solubility was reached in dimethyl sulfoxide and the minimum in cyclohexane. As for the thermodynamic functions, the entropy drives the solution process in all cases. In relation to the solubility parameter, it can be analyzed that the mathematical models offer approximations; however, the experimental data are still primordial at the time of inferring any process. [ABSTRACT FROM AUTHOR]

In this work, the absorption of sulfur dioxide (SO2) was investigated using the 1,3-propanediol (PDO) + dimethyl sulfoxide (DMSO) system, and the gas−liquid equilibrium (GLE) data were analyzed over a temperature range of 298.15–318.15 K (with a temperature gradient of 5 K) at a pressure of 123.15 kPa. By fitting the gas–liquid equilibrium data, it is observed that the process of absorption SO2 conforms to Henry's Law. The change in specific entropy, enthalpy, and Gibbs free energies of the SO2 absorption process was as well calculated. In addition, the capture and regeneration properties of the PDO + DMSO system were investigated under atmospheric pressure, and the results of regeneration experiments demonstrated that 97.3% of SO2 could be desorbed by heating and bubbling with N2. Furthermore, there was no notable reduction in absorption capacity of the absorbent solvents after multiple cycles. Finally, the FTIR spectra and computational information were noted to analyze the interaction between SO2 and the system. As a result, an intermolecular hydrogen bonding association between PDO, DMSO, and SO2 can be inferred. [ABSTRACT FROM AUTHOR]

Free barium (Ba) is critical to the formation of the active layer on the surface of dispenser cathode, which is contributed to the electron emission properties of the cathode. The Ba in the active layer of the dispenser cathode is generated by the chemical reaction between aluminate compounds and tungsten (W) under vacuum and high temperature. Nowadays, the effect of aluminate compounds on the generation of free Ba is not clear. In this work, aluminate impregnants called 411, 532 and 612 impregnants were prepared by coprecipitation method. The structure of the dominate compounds in 411, 532 and 612 impregnants were determined with density functional theory (DFT) calculation and Rietveld structure refinement. It was found that the dominate compounds of 411, 532 and 612 impregnants are Ba 3.5 Ca 0.5 Al 2 O 7 , Ba 5 CaAl 4 O 12 and Ba 3 CaAl 2 O 7 , respectively. Then, the temperature dependence of the thermodynamic properties, such as Debye temperature, entropy, heat capacity and enthalpy, of the aluminate compounds were calculated. Based on the thermodynamic properties, the potential chemical reaction between aluminate compounds and W are energetically determined by deviation Gibbs energy. The effects of different aluminate compounds on the free Ba generation were evaluated with the equilibrium Ba(g) amounts that generated by the chemical reactions between aluminate compounds and W. It is shown that the equilibrium Ba(g) amounts generated by Ba 3.5 Ca 0.5 Al 2 O 7 is higher than that by Ba 5 CaAl 4 O 12 and Ba 3 CaAl 2 O 7 , implying the superiority of electron emission performance of Ba 3.5 Ca 0.5 Al 2 O 7. The electron emission densities of the dispenser cathodes that impregnated with the 411, 612 and 532 impregnants are 5.06, 4.31 and 4.05 A/cm2, respectively. It is revealed that the Ba 3.5 Ca 0.5 Al 2 O 7 has superiority in generating free Ba, which agreed well with thermodynamic simulation results. [ABSTRACT FROM AUTHOR]

Aluminum-silicon (Al-Si) alloys are of significant interest in various engineering applications due to their favorable mechanical properties and low density. Understanding the thermodynamic and transport properties of these alloys is essential for optimizing their performance in practical applications. In this study, an angular dependent potential (ADP) for Al-Si systems is employed to describe the atomic interactions and dynamics of an Al-Si alloy system. A set of molecular dynamics (MD) simulations are performed to explore the diffusion behavior of the Al-Si alloy at different temperatures, with a specific focus on the eutectic composition of the Al-Si system. The mean squared displacement (MSD) method is applied to calculate its diffusion coefficients, enabling a detailed analysis of the system's atomic mobility and transport characteristics. Furthermore, the specific heat capacity of the Al-Si system is determined through energy fluctuation analysis, providing insights into the system's thermodynamic behavior. The obtained diffusion coefficients play a vital role in predicting the kinetics of the eutectic solidification of Al-Si alloys, while the specific heat capacity will facilitate the understanding of the thermal behavior and the energy changes associated with the eutectic reaction in such alloys. [ABSTRACT FROM AUTHOR]

A series of ether-functionalized paramagnetic ionic liquids, 1-(2-methoxyethyl)-3-alkylimidazolium tetra thiocyanate cobalt [Cn2O1IM]2[Co(NCS)4] (n = 1, 2, 3), was synthesized and characterized. The density, surface tension, refractive index, and electrical conductivity of these ionic liquids were measured at 293.15 to 343.15 K at intervals of 5 K, and their thermal expansion coefficients α were calculated. The molecular volume was obtained by measuring the pore volume and porosity. Based on Glasser theory, the standard entropy S0 (298 K), lattice energy UPOT, surface entropy Sa, and surface enthalpy, H of the ionic liquids were calculated, and the reason why the ionic liquid is in a molten state at room temperature was explained from the perspective of lattice energy. The molar surface Gibbs energy was introduced to improve the traditional Eötvös equation, which was combined with the refractive index to estimate the surface tension, obtaining a fitting index exceeding 0.99. Finally, the relationship between the electrical conductivity of the ionic liquids and temperature was investigated, and the activation energy, molar electrical conductivity, and electrical conductivity diffusion coefficient of the ionic liquids were obtained. The relationship between their properties was summarized. Compared with previously reported ionic liquids using 1-(2-methoxyethyl)-3-methylimidazolium as a cation, this type of ionic liquid has higher density and a smaller coefficient of thermal expansion. [ABSTRACT FROM AUTHOR]

Goaf water is mainly composed of weakly acidic and weakly alkaline water, but research on the oxidative thermodynamic properties of coal soaked in weakly acidic and weakly alkaline water is lacking. In this study, long-flame coal samples soaked in pure, weakly acidic, and weakly alkaline water (pH 7, 6.5, and 7.5) for 30 days were prepared. X-ray diffraction and thermogravimetry – differential scanning calorimetry were performed to analyze the microcrystalline structure and oxidative thermodynamic properties of the coal samples. Results showed that the aromatic lamellae of the soaked coal were loosely arranged, and the coal body had a strong water-locking capacity. Water could not easily dissipate, which reduced the heat absorption at the low-temperature stage and the heat release at the high-temperature stage. Soaking under different pH conditions exerted different effects on the crystal structure and oxidative thermodynamic properties of coal. Weakly alkaline water (pH = 7.5) had the most remarkable effect, weakly acidic water (pH = 6.5) had a moderate effect, and pure water (pH = 7) had the least effect. [ABSTRACT FROM AUTHOR]

This comprehensive review examines the structural, mechanical, electronic, and thermodynamic properties of Mg-Li-Al alloys, focusing on their corrosion resistance and mechanical performance enhancement. Utilizing first-principles calculations based on Density Functional Theory (DFT) and the quasi-harmonic approximation (QHA), the combined properties of the Mg-Li-Al phase are explored, revealing superior incompressibility, shear resistance, and stiffness compared to individual elements. The review highlights the brittleness of the alloy, supported by B/G ratios, Cauchy pressures, and Poisson's ratios. Electronic structure analysis shows metallic behavior with varied covalent bonding characteristics, while Mulliken population analysis emphasizes significant electron transfer within the alloy. This paper also studied thermodynamic properties, including Debye temperature, heat capacity, enthalpy, free energy, and entropy, which are precisely examined, highlighting the Mg-Li-Al phase sensitive to thermal conductivity and thermal performance potential. Phonon density of states (PHDOS) confirms dynamic stability, while anisotropic sound velocities reveal elastic anisotropies. This comprehensive review not only consolidates the current understanding of the Mg-Li-Al alloy's properties but also proposes innovative strategies for enhancing corrosion resistance. Among these strategies is the introduction of a corrosion barrier akin to the Mg-Li-Al network, which holds promise for advancing both the applications and performance of these alloys. This review serves as a crucial foundation for future research aimed at optimizing alloy design and processing methods. [ABSTRACT FROM AUTHOR]

In this paper, I present Diatomic, an open-source Excel application that calculates molar thermodynamic properties for diatomic ideal gases. This application is very easy to use and requires only a limited number of molecular constants, which are freely available online. Despite its simplicity, Diatomic provides methodologies and results that are usually unavailable in general quantum chemistry packages. This application uses the general formalism of statistical mechanics, enabling two models to describe the rotational structure and two models to describe the vibrational structure. In this work, Diatomic was used to calculate standard molar thermodynamic properties for a set of fifteen diatomic ideal gases. A special emphasis was placed on the analysis of four properties (standard molar enthalpy of formation, molar heat capacity at constant pressure, average molar thermal enthalpy, and standard molar entropy), which were compared with experimental values. A molecular interpretation for the molar heat capacity at constant pressure, as an interesting pedagogical application of Diatomic, was also explored in this paper. [ABSTRACT FROM AUTHOR]

AbstractThis study explores the development and characterization of 18 novel ZrWNb[(X)(Y)] (where XY are Hf, Ta, Mo, V, Ti) refractory high entropy alloys (RHEAs) designed to enhance mechanical robustness, thermodynamic stability, and radiation shielding effectiveness. Through a rigorous analysis, we evaluated the elastic modulus, entropy, and enthalpy of mixing, atomic size difference, valence electron concentration, and the omega parameter to understand the alloys’ phase behavior and structural integrity. Our findings revealed a broad range of elastic modulus values, indicating diverse mechanical adaptability suitable for high-stress applications. The thermodynamic assessment highlighted several RHEAs with favorable phase stability, particularly ZrWNbTaHf and ZrWNbTiTaHf, which are poised for high-performance usage due to their balanced mixing entropy and enthalpy.This study also benchmarks the RHEAs against conventional alloys, with sample R1 exhibiting the lowest fast neutron effective removal cross section, underscoring its superior neutron shielding capabilities. Additionally, R1 demonstrated exceptional photon attenuation, as evidenced by its competitive half-value layer performance across an extensive energy spectrum. Collectively, these results position R1 as a standout candidate, offering a significant advancement in materials science for applications demanding stringent radiation shielding, such as in nuclear reactor environments and space exploration. [ABSTRACT FROM AUTHOR]

Using first principles calculations, the hydrogen storage, mechanical, dynamic, thermodynamic, electronic and optical properties of YCrH 3 (Y = Ca, Sr, Ba) materials are studied for the first time. The lattice constants of CaCrH 3 , SrCrH 3 and BaCrH 3 are 3.70, 3.88 and 4.07 Å, respectively. Exploration of the mechanical properties shows that both CaCrH 3 and BaCrH 3 are brittle, whereas SrCrH 3 is ductile. In addition, all compounds are metallic, thus facilitating efficient charge transfer during hydrogen storage and release. According to the Bader partial net charges, the charge transfer in the YCrH 3 materials is analyzed. The electron density distributions show that the CaCrH 3 hydride contains ionic and covalent bonds, whereas SrCrH 3 and BaCrH 3 are ionic hydrides. Studies of optical properties reveal that CaCrH 3 has the largest static refractive index and dielectric constant. Notably, all the studied hydrides exhibit dynamic, thermodynamic and mechanical stability. The gravimetric hydrogen storage capacities are 3.08, 2.08 and 1.55 wt% for CaCrH 3 , SrCrH 3 and BaCrH 3 , respectively. These investigations provide an important theoretical basis for further exploring the application of hydride materials in the field of hydrogen storage. [ABSTRACT FROM AUTHOR]

Due to their distinct characteristics and prospective uses in several disciplines, half-Heusler (HH) materials are a family of intermetallic compounds that have garnered a lot of attention. HH compounds have a cubic crystal structure and exhibit a wide range of electronic, optical, mechanical and thermoelectric characteristics. Direct bandgap acquired by the WC-GGA (TB + mBJ) approach is 1.07 eV (2.26 eV), 0.61 eV (1.71 eV), 0.76 eV (1.68 eV), and 0 eV (0.78 eV) for KMgP, KMgAs, KMgSb, and KMgBi, respectively. Threshold power ε 2 (ω) of KMgX (X = P , As, Sb, and Bi), starts from 2.218, 1.701, 1.674, and 0.776 eV, so they exhibit the distinct peaks at 4.014, 3.742, 3.388, and 3.197 eV, correspondingly. Among these materials, the maximum value of Seebeck coefficient (S) has been attained at 300 K. Specifically, KMgP achieves the highest value of S at 3.134 mV/K, followed by KMgAs at 2.947 mV/K, KMgSb at 2.893 mV/K, and KMgBi at 1.431 mV/K, all in their respective p-type configurations. In order to determine the compound's stability, we will explore the elastic and thermodynamic properties. We will also discuss their possible applications in photovoltaic and thermoelectric devices. [ABSTRACT FROM AUTHOR]

The current investigation employs first‐principles DFT (density functional theory) calculations to examine the influence of transition metal replacements on the structural, thermodynamic, and thermoelectric properties of Cu‐based chalcogenides TMCu3Se4 (TM = Nb/Ta/V). The PBE‐generalized gradient approximation (GGA) model is utilized to compute the fundamental properties of Cu‐based chalcogenides under study. A thorough examination of the energy band structures indicates that these chalcogenides are semiconductor compounds with indirect energy bandgaps. We can infer from the calculated energy band structures that the bandgap values are 1.67, 1.77, and 1.05 eV for NbCu3Se4, TaCu3Se4, and VCu3Se4, respectively. The ZTe$$ {\mathrm{ZT}}_e $$ values for NbCu3Se4, TaCu3Se4, and VCu3Se4 are 0.661, 0.998, and 0.996, respectively. These values make them highly appropriate for usage in thermoelectric (TE) devices. The thermoelectric characteristics of pyrochlore oxides TMCu3Se4 (TM = Nb/Ta/V) suggest that these materials have promising potential for energy‐related applications. The analyzed thermodynamic properties demonstrate that the Cu0based chalcogenide materials TMCu3Se4 (TM = Nb/Ta/V) exhibit a notable level of thermal stability. [ABSTRACT FROM AUTHOR]

Herein, the properties of BZA2PbX4 (X = I, Br, and Cl) and mixed halides BZA2PbBrxCl4‐x (x = 1, 2, and 3) perovskites are comprehensively investigated, utilizing density functional theory (DFT). As there has been no prior comprehensive study on the substantial characteristics of mixed halides and the distinctive features of BZA2PbI4, BZA2PbBr4, and BZA2PbCl4 using DFT, a significant gap in the existing literature is addressed. The optical and electronic properties, band structures, band edge orbitals, and effective masses with and without spin‐orbit coupling effects are analyzed. The investigation also examines the impact of strain (tensile and compressive) on the properties of these materials. It is revealed that among the investigated compounds, BZA2PbCl4 emerges as the most thermodynamic and moisture stable. This trend is corroborated by the energy fluctuation, with BZA2PbCl4 demonstrating a narrower range, indicative of superior thermal stability. Furthermore, Voigt–Ruess–Hill approximations indicate that the mechanical moduli increase as the halide changes from I to Cl. Moreover, BZA2PbI4 exhibits the highest level of disorder, whereas BZA2PbCl4 has the lowest entropy value at the same temperature. The results highlight that these materials emerge as promising candidates for applications in the active layer of perovskite light‐emitting diodes and optoelectronic devices. [ABSTRACT FROM AUTHOR]

A density functional theory based calculations are performed to investigate structural, hydrogen storage, mechanical, electronic and thermodynamical properties of lead-free hydride perovskites XGeH 3 (X=Cs, Fr). The optimized lattice constant and hence volume against the minimum energy is obtained and found to be 4.176 Å and 4.184 Å for CsGeH 3 and FrGeH 3 respectively. The gravimetric and volumetric hydrogen storage capacity of 1.43% and 1.00%, 72.81 (g.H 2 / L) and 73.21 (g.H 2 / L) for CsGeH 3 and FrGeH 3 respectively. The density of states and electronic band structure predicted the metallic nature of both hydrides which was affirmed by the Fermi Surfaces. The calculation of Poisson's, Pugh's ratio and Cauchy's pressure suggested their brittle nature. The Debye temperature decreases with the increase of temperature while volume and entropy increase by increasing applied temperature. The present study shows the potential of lead-free hydride perovskites in hydrogen storage applications due to rather suitable gravimetric hydrogen capacity and high stability. • Hydrogen storage capacity of XGeH 3 (X = Cs, Fr) are investigated. • Gravimetric and volumetric hydrogen storage capacity of hydrides are calculated. • XGeH 3 (X = Cs, Fr) hydrides exhibit mechanical and thermodynamical stability. • Both compounds show metallic nature with 0 eV band gap. • Mechanical properties predict brittle nature of XGeH 3 (X = Cs, Fr). [ABSTRACT FROM AUTHOR]

Density functional theory is used to investigate the structural, electronic, thermodynamic and magnetic properties of the cubic antiperovskites InNNi3 and CdNNi3. Elastic and electronic properties were determined using generalized gradient approximation (GGA) and local spin density approximation (LSDA) approaches. The quasi-harmonic Debye model, using a set of total energy versus volume calculations is applied to study the thermal and vibrational effects. The results show that the two compounds are strong ductile and satisfy the Born-Huang criteria, so they are mechanically stable at normal conditions. Electronic properties show that the two compounds studied are metallic and non-magnetic. The thermal effect on the bulk modulus, heat capacity, thermal expansion and Debye temperature was predicted. [ABSTRACT FROM AUTHOR]

Thermodynamic and transport properties of particles interacting via the triangular-well potential in the range of $ 1.4 \leq \lambda \leq ~2.6 $ 1.4 ≤ λ ≤ 2.6 have been studied using perturbation theory and Molecular Dynamics simulations. We present thermodynamic properties such as vapour-liquid coexistence, vapour pressures, and density for different values of the attractive range potential. Good agreement is observed between the theoretical approach and computer simulations in a wide range of densities, temperatures, and pressures. Additionally, we show Molecular Dynamic simulation results of transport properties such as the self-diffusion coefficient as a function of both density and temperature. Finally, thermodynamic and transport properties of real fluids like oxygen, methane, hydrogen sulfide, and fluoromethane have been predicted using both approaches. Results of vapour-liquid coexistence, vapour pressures, and critical points were in excellent agreement with experimental data. The coupling of perturbation theory, Molecular Dynamics simulations, and the triangular-well pair potential offers a versatile and efficient method to explore various real fluid systems, which would include associating fluids, complex molecular liquids, and colloidal systems. This approach can advance our understanding of these systems using a simple approach and to contribute the development of more accurate and predictive models. [ABSTRACT FROM AUTHOR]

This work reports on the critical amplitudes of the thermodynamic properties of fluids, such as the specific heat, the coexistence-curve diameter, the susceptibility, the chemical potential, and the correlation length. These amplitudes are first determined from the crossover model and then correlated as a function of the acentric factor. A comparison with their values from the literature is also made. Finally, this work completes the critical amplitudes data of few fluids not reported in previous publications (Perkins et al., Int J Thermophys 34:191–212, 2013.https://doi.org/10.1007/s10765-013-1409-z). [ABSTRACT FROM AUTHOR]