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Abstract An investigation into the optical and mechanical properties of a novel borate glasses with the chemical composition of 70 B2O3-10 Li2O-10ZnO-5Bi2O3-5CaO-xEu2O3 was conducted. The glassy specimens of Eu3+-doped borate were prepared by the melting-quenching technique. An enhanced density from 3.0860 to 3.2176 g cm−3 and reduced molar volume from 29.27819 to 29.17447 (cm3 mol−1) are the outcome of increasing the concentration of Eu3+ in glasses. Plotting the extinction coefficient, dielectric constant (ε1, ε2), and refractive index (n) against wavelength reveals that they all rise as level of Eu3+ elements in the glass lattice increases. An increase in Eu3+ concentration results in a decrease in both the volume (VELF) and surface (SELF) energy loss functions. Also, all elastic-mechanical moduli (such as Young’s, Bulk, Shear, and Elongation) increase with increasing the quantity of Eu3+ ions in the glass lattice. The Young’s modulus (Y, GPa) of the glassy specimens was 34.512, 36.089, 36.504, 36.730 and 37.114 GPa for x equal 0, 0.25, 0.5, 0.75 and 1 mol ratio in the glass system, and coded by Eu-0.0, Eu-0.25, Eu-0.5, Eu-0.75 and Eu-1.0, respectively. Growing Eu2O3 levels resulted in an increase in Micro-Hardness from 2.050 to 2.146 GPa. Poisson’s ratio values for Eu-0.0, Eu-0.250, Eu-0.5, Eu-0.75 and Eu-1.0 were 0.273, 0.275, 0.277, 0.277 and 0.278, respectively.

Abstract The study was conducted on the impact of thermophysical properties on eflornithine drug solute–solvent interactions in aqueous ethyl acetate and acetone at different concentrations and temperatures. The aim of this study is to enhance the understanding of eflornithine’s behavior in different solvents, which is crucial for its effective use in pharmaceutical applications. The density, molar volume, viscometric, and conductometric characteristics of the eflornithine drug solutions (0.025, 0.05, 0.075, 0.1, and 0.125 mol/kg) in acetone and 25% (v/v) aqueous ethyl acetate were measured within a temperature range of 298.15 K–318.15 K. Based on the determined density parameters, the following parameters were assessed: viscosity (η), equivalent molar conductance, limiting apparent molar volume (V0φ), apparent molar volume of transfer (V0φtr), and apparent molar volume (Vφ). The Masson empirical relationship and the viscosity-to-Jones-Dole (JD) equation were used to evaluate the partial molar volume (Vφ), experimental slope (SV), viscosity, and density data. Temperature and concentration were used to determine each parameter. For each set of dilutions, conductometric studies were conducted in both study solvents. The gathered data was analyzed in order to evaluate the ion–solvent interactions. The Walden product Λo mηo’s positive temperature coefficient values indicate that the drug eflornithine functions as a structural modifier in acetone and aqueous acetyl acetate systems. The structure-making and breaking characteristics of the polar solvents acetone and ethyl acetate were identified.

Density, viscosity, refractive index, and ultrasonic velocity were measured for the pure materials anisole, methanol, and toluene, and for the binary mixtures: methanol—anisole and methanol—toluene. Excess molar volume VE, isobaric thermal compressibility α, excess Gibbs activation energy for fluid flow ΔGE*, and excess isentropic compressibility κSE were calculated from the measured quantities. For both binary mixtures VE and κSE were Δn > 0 and ΔGE* > 0 over the entire mole fraction composition range. Anisole mixtures exhibited more negative values for VE and κSE while more positive values were displayed for Δn and ΔGE* compared to toluene mixtures. For Δη, negative values were observed at low alcohol concentrations but positive values at high alcohol concentrations for both systems.

Starch retrogradation is desirable for some food textures and nutritional traits but detrimental to sensory and storage qualities of other foods. The objective of this study was to determine the impact of sweetener structure and concentration on the retrogradation of wheat starch gels. The effects of 20 sweeteners selected based on common food usage and stereochemical structures of interest, and ranging in concentration from 10 to 50%w/w, on the retrogradation of wheat starch gels were monitored spectrophotometrically over time. The sweeteners were sucrose, xylose, ribose, glucose, galactose, fructose, mannose, mannitol, L-sorbose, xylitol, tagatose, allulose, maltose, lactose, isomaltulose, isomalt, sorbitol, maltitol, and raffinose. Retrogradation rates and amounts were compared by Avrami equation rate constants (k = 0.1–0.7) and absorbance values measured on day 28 (Abs = 0.1–1.0), respectively. Both sweetener concentration and type significantly affected retrogradation. Gels made with sugar alcohols and high sweetener concentrations (≈≥40%) tended to retrograde more and faster, whereas gels made with sugars and low sweetener concentrations tended to have lower retrogradation rates and amounts. Sweeteners with more equatorial and exocyclic hydroxyl groups (e.g., glucose and maltitol) and those with larger molar volumes (e.g., isomaltulose and raffinose) tended to increase the rate and amount of retrogradation, particularly at higher concentrations. The impact of sweeteners on retrogradation was a balance of factors that promoted retrogradation (intermolecular interactions and residual short-range molecular order) and inhibiting behaviors (interference at crystallization sites), which are influenced by sweetener concentration and structure. Understanding which sweeteners at which concentrations can be used to promote or inhibit retrogradation is useful for product formulation strategies.

Among thermophysical properties, the surface/interfacial tension, viscosity, and density/molar volume of liquid alloys are the key properties for the modelling of microstructural evolution during solidification. Therefore, only reliable input data can yield accurate predictions preventing the error propagation in numerical simulations of solidification related processes. To this aim, the thermophysical properties of the Fe-Si and Cu-Pb systems were analysed and the connections with the peculiarities of their mixing behaviours are highlighted. Due to experimental difficulties related to reactivity of metallic melts at high temperatures, the measured data are often unreliable or even lacking. The application of containerless processing techniques either leads to a significant improvement of the accuracy or makes the measurement possible at all. On the other side, accurate model predicted property values could be used to compensate for the missing data; otherwise, the experimental data are useful for the validation of theoretical models. The choice of models is particularly important for the surface, transport, and structural properties of liquid alloys representing the two limiting cases of mixing, i.e., ordered and phase separating alloy systems.

The number of organic compounds has exceeded 40 million and further increases by 300 thousand each year. To ensure the fi re safety and the accuracy of the production process design, as well as the safe storage and transportation of materials, it is necessary to determine the level of fi re and explosion hazard of various substances. It is therefore extremely important to develop a method for determining the fi re hazard indicators and thermodynamic properties of substances, based on the minimum amount of experimental data. To solve this problem we consider it necessary to determine the dependencies between the molecular characteristics and the thermodynamic properties of homologous substances. The focus of the present research is on the homologous series of n-alkyl benzenes. The analysis determined that the thermodynamic functions of substances additively depend on the molar weight of n-alkyl benzenes in the homologous series. Similar dependence was observed for the fl ash point of n-alkyl benzenes. Taking into account the fact that the fl ash point values and the Helmholtz energy tend to change depending on the molar weight of the substances in the homologous series, it seems practical to establish their interrelation. The corresponding equations were derived. Similar dependencies were previously observed for the homologous series of n-alkyletanoats, aliphatic ketones, n-alkylamines, and alcohols.The established regularities and proposed equations allow us to forecast the properties of homologous series of substances with suffi cient accuracy.

Two series of glasses were synthesized by conventional rapid melt-quench method for different glass systems 55[(PbxBi1-x).TiO3]-44[2SiO2B2O3] and 65[(PbxBi1-x).TiO3]-34[2SiO2B2O3] doped with 1 mole percent of La2O3. X-ray diffraction study of synthesized glass sample shows amorphous nature while the glass ceramic sample revealed a cubic crystal structure due to devitrification of the glass as major crystalline phase of bismuth titanium oxide. X-ray absorption spectroscopy measurements in transmission mode were carried out and confirm the maximum value of absorption coefficient, 3.05 at energy 13450 eV for lead free glass ceramic sample. Scanning electron microscopy and contact angle measurements were also performed to explain the surface morphology. Energy dispersive X-ray analysis confirmed the presence of grains of bismuth titanium oxide and its elemental analysis with O, Ti, Si, Bi nanoparticles. The inclusions of La2O3 results in development of well interconnected crystallites were formed as major phase of bismuth titanium oxide.

Melt dynamics and glass Topological phases of especially dry and homogenized binary AsxS100−x melts/glasses are examined in Modulated-DSC, Raman scattering, and volumetric experiments. In the S-rich glasses (12% < x < 23%), direct evidence for the elusive 537 cm−1 stretch vibrational mode of the Quasi-Tetrahedral (QT), S = As(S1/2)3, local structure is observed in FT-Raman scattering once melts are homogenized and glasses cycled through Tg+10°C for an extended period. The enthalpy of relaxation at Tg, ΔHnr(x), fragility index, m(x), Molar volumes, Vm(x) each display three distinct regimes of variation. Specifically, m(x) displays a Gaussian like global minimum (fragility window), and ΔHnr(x) displays an abrupt square-well like variation (reversibility window), while Vm(x) displays a Gaussian-like local minimum (Volumetric window) in the isostatically rigid phase (22.5% < x < 28.5%). At low x (< 20%) in the Flexible phase, glasses are segregated with a S8-rich nanophase that decouples from the As-S glassy backbone. At medium x (22.5% < x < 28.5%) glassy backbones form an isostatically rigid phase displaying a vanishing ΔHnr(x) term, and compacted structures with corresponding melts being superstrong (m < 20). At high x (28.5% < x < 40%) in the Stressed-Rigid phase, glasses possess an increasing ΔHnr(x) term, and melts become increasingly fragile, with m(x) >20 as x increases. Taken together, these results underscore that superstrong melts yield isostatically rigid glasses, while fragile ones form either Flexible or Stressed-rigid glasses upon cooling. The onset of the rigidity transition near = 2.22, instead of the usual value of = 2.40, is identified with presence of QT local structures in addition to Pyramidal As(S1/2)3 local structures in the glassy backbone, and with a small but finite fraction of polymeric Sn chains being decoupled from the backbone.

Scores of glass compositions in the equimolar GexAsxSe100−2x ternary system are synthesized across the 0 < x < 26% range, and their homogeneity tracked by ex-situ Raman profiling. In synthesis, we alloyed the starting materials to homogenize until the variance, Ge, in Ge content “x,” across a 1.5-g sized batch composition of 20 outside that range, thus establishing a fragility window. The close correlation between the variations of m(x) and ΔHnr(x) underscores that super-strong melts formed in the fragility window form Intermediate Phase (IP) glasses in the reversibility window, while fragile melts formed at non-IP compositions give rise to either flexible or stressed-rigid glasses. Molar volumes of glasses reveal a global reduction for IP glass compositions, thereby underscoring the compacted nature of the isostatically rigid networks formed in that phase. Evidence for specific dynamic features of the different phases is provided by molecular dynamics simulations, which indicate that the diffusivity is minuscule for x > 17% and increases substantially in the flexible phase. These results show that liquid dynamics and fragility encode glass topological phases in this ternary chalcogenide. The optimization of the glass-forming tendency for IP compositions, the stress-free nature of these networks, and the qualitative suppression of aging, are features that all point to their ideal nature. These ideas of IP glasses as ideal glasses are at variance with the notion that ideal glasses possess a low configurational entropy and form at Tg values that approach the Kauzmann temperature. IP networks display, adaptability, high glass-forming tendency, stress-free nature, and high configurational entropy of networks.

Melt and quench technique was used for the preparation of glassy samples of the composition x Bi2O3-(1-x) B2O3 where x= .05 to .040. XCOM computer program is used for the evaluation of gamma-ray shielding parameters of the prepared glass samples. Further the values of mass attenuation coefficients, effective atomic number and half value layer for the glassy samples have been calculated in the energy range from 1KeV to 100GeV. Rigidity of the glass samples have been analyzed by molar volume of the prepared glass samples.

Variation of dynamic viscosity, density and enthalpy as a function of mole fraction of amine (tri-n-octylamine, triisooctylamine, bis(2-ethylhexyl)amine) in bis(2-ethylhexyl) phosphoric acid (D2EHPA) or Cyanex 272, (bis(2,4,4-trimethylpentyl)phosphinic acid) has been determined at 25 °C. Valuable information regarding structuration and destabilization of the corresponding ionic liquids has been deduced from these data. A simple model describing the variation of dynamic viscosity as a function of mole fraction of amine has been used to determine the speciation in these mixtures. Extraction tests of cobalt(II) and nickel(II) by D2EHPA-amine mixtures have shown the highest cobalt(II)-nickel(II) selectivity has been achieved with D2EHPA-2-ethylhexylamine mixture as cobalt(II) extraction efficiency of 77% was obtained, while no significant nickel(II) extraction was observed at a chloride concentration of 3 mol·L−1.

In order to optimize the removal of boron during the refining of slag to obtain solar grade silicon, the density of molten slag was measured by an improved Archimedean method within a temperature range from 1073 to 1373 K. It was found that the density of molten slag at 1723 K can be deduced by linear fitting, and that the slag density decreases with increasing temperature. However, a reduction in slag density occurs with decreasing CaO concentration. An increase in the molar volume of slag was also observed with increasing temperature.

Density, viscosity, surface tension and molar volume of propylene glycol + water mixtures at 293, 298, 303, 308, 313, 318, and 323 K are reported, compared with the available literature data and the Jouyban–Acree model was used for mathematical correlation of the data. The mean relative deviation (MRD) was used as an error criterion and the MRD values for data correlation of density, viscosity, surface tension and molar volume at different investigated temperatures are 0.1 ± 0.1%, 7.6 ± 6.4%, 3.4 ± 3.7%, and 0.4 ± 0.4%, respectively. The corresponding MRDs for the predicted properties after training the model using the experimental data at 298 K are 0.1 ± 0.2%, 12.8 ± 9.3%, 4.7 ± 4.1% and 0.6 ± 0.5%, respectively for density, viscosity, surface tension, and molar volume data.

It is an important issue to calculate the physicochemical properties of aluminosilicate melt based on some known data. However, it is also a difficult issue to do so, especially for a multicomponent slag system since the available data are very limited due to the difficulty of experimental measurement at high temperature. In this paper, a method is suggested to resolve this problem, which is particularly significant. This model can be well used to estimate the electrical conductivity, viscosity, molar volume and surface tension of aluminosilicate melt.

Using the method of solvation Conductor-like Screening Model (COSMO) and the method of Amovilli-Menucci GAMESS program content, we estimated the free energies of van der Waals and electrostatic of organic molecules in their dielectric medium. With these energy and volume of the solute cavity, we designed two models of structure-property relationship (QSPR) to determine the molar volume and enthalpy of vaporization to the ebullition temperature of organic molecules. The best obtained model using the molecular volume presents a correlation equal to 0.9949 and the correlation of the model using the enthalpy of vaporization was 0. 9895.

Values of molar refraction for every studied mixtures show linear plots versus molar fractions of triglyceride. Values of molar volume show this behaviour, but only for tributyrin-butanol or tricaprylin-butanol miscellas. However, in tributyrin-ethanol mixtures, volume contractions have been found, whereas triacetin-butanol and tributyrin-hexanol show volume expansions. These facts are related to the mode of being structured of the alcohol and triglyceride molecules in mixtures. A linear relationship between molar volume and temperature have been found, and also a linear dependence between the coefficient of thermal expansion at constant pressure and the molar fraction of triglyceride.