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Densities of aqueous solutions of MnSO$$_4$$ 4 , CoSO$$_4$$ 4 , NiSO$$_4$$ 4 and CuSO$$_4$$ 4 have been measured by vibrating tube densimetry up to near-saturation concentrations over the temperature range 293.15 $$\le T/$$ ≤ T / K $$\le $$ ≤ 343.15 at 5 K intervals and at 0.1 MPa pressure. Apparent molar volumes, $$V_\phi $$ V ϕ , calculated from the densities revealed close similarities among all four electrolytes, with their $$V_\phi $$ V ϕ values essentially differing by constant concentration-independent addends for each salt at each temperature. It was found that there is an almost linear relationship between $$V_\phi $$ V ϕ (MSO$$_4$$ 4 ,aq) and the M–O bond length of the hydrated cations obtained from structural studies. This relationship can be used to predict values of $$V_\phi $$ V ϕ (MSO$$_4$$ 4 ,aq) for other sulfate salts over wide ranges of concentration and temperature, providing that the requisite structural data are available. Measurements of selected ternary, quaternary and quinary mixtures of these electrolytes at constant total concentrations showed that their $$V_\phi $$ V ϕ values almost always exhibit linear mixing (Young’s rule) behavior at all temperatures investigated. This finding can be exploited to predict the volumetric properties of solutions containing complex mixtures of bivalent metal sulfates.

This work deals with the study of the influence of adding AgI content on the physicochemical properties of (0.5As2Se3–0.5GeTe)100−x(AgI)x chalcohalide glassy system. The molar volume, excess volume, packing density, and compactness were determined. The number of coordination (average), number of constraints, cross-linking density as well as mean bond energy were computed and were found to decrease by adding AgI content. Floppy modes and average single bond energy were found to decrease. A linear relationship linking the heat of atomization to the cohesive energy was proved. Different estimates showed that the optical band gap decreased, and good agreement was found with the experimental results. The results of these estimates were used to determine the positions of the valence and conduction bands. The study also explains the interdependence between physiochemical properties and the optical band gap.

In the present work, we obtained density (ρ123), speed of sound (u123), excess molar volume (Vm123E), and deviation in isentropic compressibility (Δks123) for ternary mixtures of {[BMIM][BF4] (x1) ...

To effectively develop the rare earth elements resources from the geothermal waters, it is essential to understand the volumetric properties of the aqueous solution system to establish the relative thermodynamic model. In this study, densities of YCl3 (aq) at the molalities of 0.08837–1.60639 mol·kg−1 from 283.15 K to 363.15 K at 5 K intervals and ambient pressure were measured experimentally by an Anton Paar digital vibrating-tube densimeter. Based on experimental data, the volumetric properties including apparent molar volume (Vϕ) and the coefficient of thermal expansion of the solution (α) of the binary systems (YCl3 + H2O) were derived. The 3D diagram (mi, T, Vϕ) of apparent molar volumes against temperature and molality was plotted. On the basis of the Pitzer ion-interaction model of electrolyte, the Pitzer single-salt parameters ( β MX 0 v , β MX 1 v , and C MX v ) for YCl3 and temperature-dependence equation F(i, p, T) = a1 + a2ln(T/298.15) + a3(T-298.15) + a4/(620-T) + a5(T-227) as well as their coefficients ai (i = 1–5) in the binary system were obtained for the first time. The values of Pitzer single-salt parameters of YCl3 agree well with the calculated values corresponding to the temperature-dependence equations, indicating that single-salt parameters and temperature-dependent formula obtained in this work are reliable.

Background The influence of deep eutectic solvents (DESs) {(choline chloride (ChCl): lactic acid (LA) and choline chloride: malonic acid (MA)} with different mass fractions of DES on the thermodynamic, transport and electrochemical properties of lithium perchlorate (LiClO4) in propylene carbonate (PC) systems were studied. These investigations are in line with proposing new green electrolyte solutions for future electrochemical applications. Methods Density, speed of sound and viscosity at T = 288.15–318.15 K of (LiClO4 + PC + DESs) solutions have been measured from which the apparent molar volume, apparent molar isentropic compressibility, standard partial molar volume, partial molar isentropic compressibility, partial molar volumes of transfer, partial molar isentropic compressibility of transfer and viscosity B-coefficient were calculated. Also density functional theory (DFT) of LiClO4 with DESs in PC solvent was applied. As well as linear sweep voltammetry (LSV) measurements were performed. Significant findings The calculated thermodynamic and transport parameters indicated that interactions of ChCl/LA with LiClO4 in the presence of PC are more favorable than ChCl/MA. Then, the DFT was applied to find further evidence for these solute-solvent interactions and confirmed the thermodynamic and transport results. Finally, LSV measurements were performed for investigating the electrochemical potential windows of the systems.

The Bulk (100-x)Ge3Se7 - (x)As2Te3 (0 ≤ x ≤ 30) glassy alloys were prepared using the melt quenching technique. The elastic moduli (Bulk (K), Micro-hardness (H), Young (Y)), and Poisson's ratio (Pr) of the prepared glasses have been determined using the measured values of the ultrasonic velocities and density (ρ). Values of ρ were measured, then the molar volume (Vm) was estimated theoretically. The DSC thermograms are used to determine the glass transition temperature (Tg). The thermal evaporation method was used to prepare the (100-x)Ge3Se7- (x)As2Te3 (0 ≤ x ≤ 30) thin films under a vacuum of about 10−4Pa. The absorbance (A) of the films in the spectral range from 0.45 to 0.85 μm has been measured, then the absorption coefficient (α) and energy gap (Eg) were determined. The Chemical Bond Approach (CBA) has been used successfully to estimate theoretically various physical and structural characteristics of the studied system. Theoretical values of Eg and Tg have been obtained using different methods. The results proved a remarkable agreement between the theoretical and experimental values for both the Eg and Tg. The Eg values decreased from 2.1 to 1.73 eV by increasing the As2Te3 content from 0 to 30 at. %. Therefore, these compounds can be used as an absorbing layer for electromagnetic radiation in photovoltaic devices and sensors.

Different batches of weathered basalt ranging from 100 to 50 %, in combination with by-pass cement dust, were used to prepare the glass compositions. Different techniques utilized such as differential thermal analysis, X-ray diffraction, density, FTIR, the mass attenuation coefficients, appropriate atomic number (Zeff), and effective electron density (Neff), were examined for the prepared glass and glass-ceramics samples at different photon energies. In the present study, it was revealed that as the molar volume decreases, the density increases. The experimental and theoretical effects of the mass attenuation component were mostly consistent at different energies. The results revealed that glass samples (WB100) containing a higher percentage of basaltic rocks demonstrated higher radiation protection than those with lower rate (WB50). In addition, glass-ceramics displayed enhanced radiation and gamma rays protection than glass. Therefore, we recommend using glass- ceramics containing 100 % basalt as a protective shield against gamma rays with a lower thickness and higher protection.

The density, speed of sound and viscosity data of drug pentoxifylline in aqueous solutions of glucose (monosaccharide) and lactose (disaccharide) were determined. The various properties of the solutions were characterized and their structural features determined by varying the concentrations of solute and solvent at atmospheric pressure and at five different temperatures (293.15, 298.15, 303.15, 308.15 and 313.15) K. Infinite dilution limiting apparent molar volume ( $$V_{\phi }^{0}$$ ) and limiting apparent molar isentropic compression ( $$K_{\phi ,S}^{0}$$ ) parameters and their variation tendencies were considered in terms of the interactions between solute and solvent. The transfer parameters ( $$\Delta_{{{\text{tr}}}} V_{\phi }^{0}$$ and $$\Delta_{{{\text{tr}}}} K_{\phi ,S}^{0}$$ ) were positive and increased with increase in the concentrations of glucose/lactose in aqueous medium. Limiting apparent molar expansivity ( $$E_{\phi }^{0}$$ ), Hepler’s constant $$\left( {{{\partial^{2} V_{\phi }^{0} } \mathord{\left/ {\vphantom {{\partial^{2} V_{\phi }^{0} } {\partial T^{2} }}} \right. \kern-\nulldelimiterspace} {\partial T^{2} }}} \right)$$ and hydration number (nH) were also evaluated. The viscosity data have also been evaluated using the Jones–Dole equation. The results, analyzed using spectroscopic data, are discussed and rationalized in terms of various interactions.

The interaction in the binary solution of polyethylene glycol 200 (PEG 200) and polyethylene glycol 400 (PEG 400) with d-panthenol at the variation of temperatures has been surveyed by merging acoustic and volumetric processes. The density and speed of sound of PEG 200 and PEG 400 mol $${\mathrm{kg}}^{-1}$$ in the aqueous solution of d-panthenol in the concentrations of (0.00, 0.03, 0.06 and 0.09) at temperature, T = (288.15, 298.15, 308.15 and 318.15) K and experimental pressure 0.1 MPa is measured. From the data of density, the apparent molar volume $${(V}_{\phi })$$ , partial molar volume $${(V}_{\phi }^{0})$$ and partial molar volume of transfer $$(\Delta {V_{\phi }^{0}} )$$ , for PEG 200 and PEG 400 in the aqueous solution of d-panthenol is calculated along with the apparent molar isentropic compression $${(K}_{\phi })$$ , partial molar isentropic compression $${(K}_{\phi }^{0})$$ and the partial molar isentropic compression of transfer, $$(\Delta {K_{\phi }^{0}} )$$ , from the of the speed of sound data. Using the partial molar volume of transfer and partial molar isentropic compression of transfer the pair and triplet coefficients as the functions of temperatures are calculated as well as the partial molar expansibilities ( $${E}_{\phi }^{0}$$ ) with its first-order derivative $$\left( {\partial {E_{\phi }^{0}} /\partial T} \right)_{P}$$ are obtained. Further, these calculated parameters are used to describe the results in terms of (solute–solute); (solute–solvent) interactions including the structure making/breaking ability of polyethylene glycols in the aqueous solution of d-panthenol.

In this report, the physical, optical, and radiation shielding features of 65PbO–(20−x)B2O3–15Bi2O3–xAlO9P3 (x: 0, 2.5, 5, and 7.5 mol%) glasses coded as PBB-Al0, PBB-Al1, PBB-Al2, and PBB-Al3, respectively, are presented. Gamma-ray linear and mass attenuation coefficients were estimated via FLUKA simulations and validated by XCOM calculations for photon energies between 0.1 and 10 MeV. Also, charged particles (electron (e−) proton (p+), α-particle (He2+) and carbon ion (C+)) attenuation competence, $${\Sigma }_{R}, {\sigma }_{tot}$$ , and scattering cross-section for fast, thermal, and cold neutrons of the glasses were estimated. With an increase in AlO9P3 doping rate, the glass density ρglass exhibits a downward trend from 7.358 to 6.987 g⋅cm−3 for PBB-Al0 to PBB-Al3, respectively. Contrary to this, the molar volume Vm grew from 36.06 to 39.77 cm3⋅mol−1, as a function of insertion ratio in AlO9P3 from 0 to 7.5 mol%. Optical parameters such as refractive index (n), dielectric constant (ϵ), molar refractivity (Rm), and molar polarizability (αm) of the glasses were found to vary depending on AlO9P3 content. Analysis of the obtained radiation shielding parameters revealed that gamma-ray shielding capacity of the glasses follows the trend PBB-Al0 > PBB-Al1 > PBB-Al2 > PBB-Al3. However, the influence of Al(PO3)3 on the charged particle shielding abilities of the glasses was insignificant. Furthermore, $${\Sigma }_{R}$$ ranged between 0.1095 and 0.11113 cm−1. $${\sigma }_{tot}$$ for thermal neutron declined as the weight fraction of B, Pb, and Bi declined in the glasses. On the other hand, the scattering cross-section of cold neutrons in the glasses rose throughout the considered energy spectrum as Al(PO3)3 concentration declined in the glass matrix. Comparatively, the investigated PBB-Alx glasses are superior gamma-ray photon shields than ordinary concrete, RS-360 commercial glass shield, P2 polymer, and some recently investigated glass shields. This study concludes that the presently investigated glasses have a significant role to play as alternative radiation shields in contemporary and future application of radiation.

The glass system 22SiO2- 23Bi2O3-37B2O3-13TiO2 $$-(5-x)$$ LiF- $$x$$ BaO $$, (0\le x\le 5) \text{m}\text{o}\text{l}.\text{\%}$$ . was fabricated using melt-quenching techniques. X-ray diffraction and ultrasonic techniques were used to characterize the glasses. X-ray diffraction patterns were used to prove that fabricated glasses are amorphous. The impacts of incorporating BaO on the composition dependence of the elastic characteristics of fabricated samples were explained. Density of the manufacture glasses increment, and molar volume reduced. The elastic moduli were investigated experimentally then compared using theoretical arguments. Makishima – Mazinize model were used to determine the elastic moduli theoretically for fabricated samples. Elastic moduli increase with BaO, and experimental and theoretical elastic moduli are in good agreement. Deviation values between elastic moduli (both experimentally and theoretically) were estimated. All the experimental variations values of elastic moduli of fabricated glasses were increment as BaO increased. Latent heat of melting, diffusion constant, and Gruneisen factor have been used to link the mechanical and thermodynamic characteristics of manufactured glass.

The development of the Li-ion battery Industry in a green way is crucial for human beings' future. Ionic liquids (ILs) are green cosolvents that could be applied in Li-ion battery electrolytes. A thermodynamic study has been carried out for a Li-ion electrolyte (propylene carbonate (PC) + LiCl and LiBr) in the presence of IL 1-alkyl-3-methylimidazolium thiocyanate [RMIM][SCN] (R = butyl, hexyl, and octyl). The studied thermodynamic properties were density, speed of sound, apparent molar volume, and compressibility. The effect of ILs in propylene carbonate (PC) has been investigated under atmospheric pressure at T = (288.15-318.15) K. Also, a microscopic approach using scaled particle theory has been implemented. The solvation effect of lithium halides, LiX (X = Cl-, Br-), on the volumetric and compressibility properties of the ILs has been studied at 298.15 K. The results show that [OMIM][SCN] has the strongest interactions with PC in the studied ILs and these interactions are more weakened with the addition of LiBr than LiCl. According to the partial molar compressibility results, the systems containing [OMIM][SCN] could be used under pressure more beneficially than other systems from the thermodynamic aspect of view.

The Al–Si alloys exhibit many unique properties, but not enough work has been dedicated to their thermophysical properties. In this work, the effect of phosphorus modifier on the density, molar volume and solidification shrinkage rate of Al-25% Si alloys was investigated by using the indirect Archimedes method. The results show that both density–temperature and molar volume–temperature curves show three inflection points: the liquidus temperature point, the eutectic transformation starting point and the finishing point. The density of the solidus linearly decreases and that of the liquidus linearly increases with phosphorus modifier content. Compared with Vegard’s law, the molar volumes show a negative deviation. Finally, the solidification shrinkage rate is calculated from the densities of solidus and liquidus.

The numerical descriptor gathers the data from the molecular graphs and helps to know the characteristics of the chemical structure known as topological index. The QSAR/QSPR/QSTR studies are benefited with the significant role played by topological indices in the drug design. Topological indices provide the information about the physical/chemical/biological properties of chemical compounds. The Zagreb indices are widely studied because of their extensive usage in chemical graph theory. Inspired by the earlier work on inverse sum indeg index (ISI index), novel topological index known as SS index is introduced and computed for four dendrimer structures. Also, the strong correlation coefficient between SS index and 5 physico-chemical characteristics such as boiling point (bp), molar volume (mv), molar refraction (mr), heats of vaporization (hv), and critical pressure (cp) of 67 alkane isomers have been determined. It is found that newly introduced index has shown good correlation in comparison with three most popular existing indices (ISI index and first and second Zagreb indices). In the last part, the mathematical properties of SS index are discussed.

Experimental data of density have been measured for binary liquid mixtures containing {amines (n-butylamine, or s-butylamine, or t-butylamine, or diethylamine, or propylamine) + water}, over the entire range of composition at temperatures between 283.15 and 303.15 K, and atmospheric pressure. The density values enabled the determination of the thermal expansion coefficients. The excess molar volume, $${\text{V}}_{\text{m}}^{\text{E}}$$ , was calculated using the experimental data, from which a Redlich–Kister type polynomial was fit, enabling the determination of the partial molar volumes, the excess partial molar volumes, the apparent molar volumes and the excess partial molar volumes at infinite dilution. The $${\text{V}}_{\text{m}}^{\text{E}}$$ values were also used to test the applicability of the Extended Real Associated Solution Model (ERAS Model). The results for the studied systems suggest that structural effects and chemical interactions must predominate over other possible effects. The magnitude of $${\text{V}}_{\text{m}}^{\text{E}}$$ for the studies systems led to the following order: n-butylamine > propylamine > s-butylamine > diethylamine > t-butylamine.

The structure, thermal stability and dielectric properties of aluminoborosilicate glasses with different contents of Pr2O3 were researched by XRD, FT-IR, DSC and electronic impedance analyzer. FT-IR results showed that the addition of Pr2O3 enhanced the degree of polymerization of glass network. The molar volume decreased at first and then increased, which reached the minimum value with the content of Pr2O3 up to 1.5 mol%. With the addition of Pr2O3 the glass transition temperature (Tg) showed an upward trend, while Dietzel's thermal stability (ΔT) and the Saad parameter (S) both increased initially to be followed by a decrease, which indicated that the thermal stability of glass can be improved by doping proper content of Pr2O3. The dielectric constant (er) and dielectric loss (tanα) both decreased at first then started to go up as the content of Pr2O3 increased. When Pr2O3 content moved up to 0.5 mol% and 1.5 mol%, the er and tanα reached the minimum values 4.68 and 3.13 × 10–4, respectively.

Based on thermodynamic calculations, it is shown that in the temperature range of 298–1273 K, heating and cooling of aluminum are thermodynamically equilibrium processes. When aluminum is heated, the molar volume energy of Gibbs decreases and the molar boundary energy of nanocrystals increases. When aluminum is cooled, the molar volume energy of Gibbs increases and the molar boundary energy of nanocrystals decreases. Liquid aluminum is a nanostructured system. Dendritic microcrystals are formed from nanocrystals. They play a large role in the processes of changing the structure of aluminum during its heating and cooling.

Objectives. The increased use of unmanned aerial vehicles necessitates the search for jet fuels based on hydrocarbon materials with high energy intensity and physical density. The purpose of the work was to analyze the influence of various factors on the mass energy intensity of hydrocarbons. This analysis is required to substantiate the algorithm for locating energy-intensive CnHm structures.Methods. Combustion energy was calculated using additive procedures. The calculations were performed using Microsoft Excel.Results. During the analysis of the mass energy intensity of CnHm hydrocarbons, the m/n ratio was discovered to be the decisive factor for achieving high values of the mass energy intensity of hydrocarbons. The energy intensity decreases when moving from alicyclic to cyclic hydrocarbons, and this decrease is not compensated by the production of strain energy. An additive scheme that allows the molar volume of hydrocarbons to be predicted with sufficient accuracy is proposed for calculating the volumetric enthalpies of combustion.Conclusions. According to the thermodynamic analysis, n-alkanes have the highest mass energy intensities. The technology for extracting n-alkanes from oil fractions is well developed, and a decrease in the hydrogen content in the fuel results in a decrease in the mass energy intensity. It appears improbable that the mass and volumetric energy intensities of hydrocarbons seem will reach their maximum values simultaneously. Hydrocarbons that have a high m/n value, 2, 3, 4, 5, 6-membered rings, and phenyl fragments may have relatively high mass and volumetric energy intensities at the same time.

In this study, a series of glass systems with a composition of (49 − x)H3BO3–35TeO2–15PbO–1.0Nd2O3–xY2O3 (x = 0.0, 0.5, 1.0, 1.5, 2.0, and 2.5 mol%) was prepared via melt-quench technique. The effect of Y2O3 content on the density, molar volume, oxygen packing density, elastic, and structural properties were investigated. The density and molar volume were found to vary concerning Y2O3 content. Ultrasonic non-destructive testing was employed at room temperature for measuring the elastic properties of the prepared glass samples. The density data, ultrasonic velocities, and measured elastic moduli were found to be composition dependent with Y2O3 content. The Y2O3 modifier was expected to change the physical properties of neodymium-doped lead borotellurite glasses. The structure analyzed using X-ray diffraction was confirmed the amorphous nature of the prepared glasses. Fourier Transform Infrared Spectroscopy has been carried out and reveals that the inclusion of Y2O3 into the glass system tends to increase the number of bridging oxygen atoms. All element study of the glass sample was proved by energy dispersive X-ray analysis.

Density, speed of sound and viscosity data for the binary mixtures (1,4-dioxane (1) + water (2)), were measured over the whole composition range at temperatures T = (295.15, 298.15, 301.15, 304.15, 307.15, 310.15 and 313.15) K and at the atmospheric pressure. From experimental data, the excess molar volume, isobaric thermal expansion coefficient, excess of isobaric thermal expansion coefficient, excess speed of sound, isentropic compressibility, excess of isentropic compressibility, intermolecular free-length, the excess intermolecular free-length, the viscosity deviation, the excess free Gibbs energies of activation of viscous flow, the internal pressure, excess internal pressure, acoustic impedance, the excess acoustic, and the free volume were calculated. The excess parameters were fitted by the Redlich–Kister polynomial equation to derive the coefficients and estimate the standard error values. The nature of molecular interactions between the two components of the mixture, have been discussed by means of the thermodynamic properties.

A glass system of 40P2O5–(21 − x) Na2O–38ZnO–x Co3O4–1CuO where (x = 1, 2, 3, 4 and 5) has been prepared by melt quenching technique. The density of the glasses was measured, and molar volume was calculated. The structure has been investigated using IR spectroscopy. The spectral analyses showed that the addition of Co3O4 to P2O5 glass is unequivocally influencing the short-range order of the glassy matrix. The spectra also denote the formation of P–O–Co bonds in the glasses that replace P–O−–Na+ bonds. The results are related to the dual role of cobalt ions as a glass former and modifier.

The fabrication and spectroscopic characterization of varying content of Y3+ doped bismuth titanate borosilicate glasses by the melt quenching technique are described. The nature of glass system composition was established using XRD spectra analysis. The manufactured glasses’ molar volume reduced while their density and refractive index continued to increase. UV transmission, absorption, polarizability, and basicity are all found to be highly sensitive to Y2O3 content. The optical bandgap and Urbach energy have been discussed in detail. It was observed that, as Y2O3 increase, the optical bandgap increases, while Urbach energy decreases. Based on the results of the calculations of molar Refractivity, molar polarization, polarizability, optical basicity and dispersion, the fabricated glasses are thought to be very semi-covalent. Metallization of the present glasses are increased.

From the density (ρ) and speed-of-sound (u) measurements, the interactions of the drug diphenhydramine-hydrochloride (DPH) with three imidazolium-based ionic liquids (ILs) (1-butyl-3-methylimidazolium chloride, [C4mim][Cl], 1-hexyl-3-methylimidazolium chloride1, [C6mim][Cl], and 1-methyl-3-octylimidazolium chloride, [C8mim][Cl]) have been investigated in aqueous medium at T = 293.15-313.15 K and experimental pressure p = 0.1 MPa. From the density calculations, the apparent molar volume (V ϕ) and the apparent partial molar volumes of transfer (Δ t V ϕ o) have been determined for various solutions of DPH in aqueous solutions of different ILs. In addition, from the speed-of-sound data, the apparent molar isentropic compressibility (K ϕ), apparent partial molar isentropic compressibility (K ϕ o), and apparent partial molar isentropic compressibility of transfer (Δ tKϕ ο ) have been calculated. The pair and triplet interaction coefficients are derived from apparent partial molar volumes of transfer. For the present mixtures, the absorption spectra have been also recorded using a UV-visible spectrophotometer. Using Hepler's constant, the structure-making nature of the solute has been confirmed. All these calculated parameters provide detailed insights into various physicochemical interactions prevailing in the ternary system and confirm the presence of a strong attractive interaction between DPH and ILs.