Computational studies on physico-chemical properties in the quality analysis of corn and peanut oil

Oils are commonly used in cooking as a frying medium which has been constantly subjected to different levels of heating. In this work, we have considered the most commonly used oils namely peanut oil and corn oil. Quality analyses of corn and peanut oils were made by relating macroscopic properties (ultrasonic velocity, viscosity, and density) to microscopic parameters (intermolecular free length, adiabatic compressibility etc.,) by subjecting them to six cycles of heating (190 ˚C). Variation in the mentioned property indexes, the degree of degradation and reusability for the next heating cycle that could be used in the food industry and processing were monitored. Using Newton-Laplace and Wood’s equation, the adiabatic compressibility, acoustic impedance, and intermolecular free length of the oil were estimated from the experimental data. Ultrasonic velocity was observed linearly as related to viscosity with the dependency factor (R2 = 0.932). With the aid of experiential data, the physical thermodynamic parameters, particularly particle size, packing factor, chemical potential, and L-J potential were computed. A high correlation factor was observed by fitting ultrasonic velocity, viscosity, and density to Parthasarathy and Bakshi, and Rodenbush equations. In the study, ultrasonic velocity, a macroscopic parameter, could be decoded to determine the microscopic variations in oil subjected to different temperatures in an industrial application.

THERMO PHYSICAL PROPERTIES OF TERNARY MIXTURES OF 1-HEXANOL/1- OCTANOL CONTAINING N-N-DIMETHYLFORMAMIDE AND TOLUENE AT 303.15 K

In the present work, ultrasonic velocity (u), viscosity (η) and density (ρ) of ternary mixtures of 1-hexonal and 1-octanol with dimethylformamide in toluene at 303.15 K have been measured over the entire composition range. From the experimental data, acoustical parameters such as adiabatic compressibility (β), intermolecular free length (L ), free volume (V ), acoustic impedance (Z), excess adiabatic compressibility , excess free length , excess free f f E E (b ) (L )f volume and excess acoustic impedance have been computed. The variation of these properties with composition are E E (V ) (Z ) f discussed in terms of molecular interactions between unlike molecules of the mixtures.

Thermo Acoustic Study of Salicylaldehyde in Carbon Tetra Chloride at 303.15K, 308.15K, 313.15K

Thermo-acoustic study in binary mixture of salicylaldehyde and carbon tetra chloride were reported at 303.15K, 308.15K, 313.15K. The molecular interaction have been carried out by computing various thermo acoustical parameters i.e. Intermolecular free length (Lf), Specific acoustic Impedance (Z), Molar Volume (Vm), Available Volume (Va), Isentropic compressibility (S) and other constant and the excess value of foresaid parameters have been evaluated by using ultrasonic velocity, density, viscosity data, the results of these parameters conclude the strength of molecular interaction. Keywords: Excess values of Salicylaldehyde, Acoustic Parameters, Molecular Interaction.

Study of nitrazepam drug interaction with alcohol: An ultrasonic and physiochemical investigation

The intermolecular interaction between the constituent components of liquid mixtures can be revealed by ultrasonic analysis. In the present study, interaction of nitrazepam drug with methyl alcohol has been studied and presented using ultrasonic tools. The investigation involves calculation of ultrasonic velocity (ν), density (ρ), viscosity (η) and the associated derived parameters. The specific acoustic impedance (Z), isentropic compressibility(β), relaxation time (τ), intermolecular free length(L_f) and solvation number Sn are calculated to reveal the interaction information. The solvent-solvent and solute-solvent interaction between the nitrazepam and alcohol molecules is considered. To see the impact of nitrazepam drug with alcohol in ordinary day to day scenario, investigation is carried out at normal temperature and pressure conditions with temperature range varying from 303K to 313K range. The results indicate increased molecule association of nitrazepam drug in presence of alcohol. This study suggests the presence of synergistic depressants effect, when nitrazepam drug is used with alcohol.

Acoustical Parameters of Polyvinyl Alcohol

Ultrasonic investigation provides a wealth of information in understanding the intermolecular interaction of solute and solvent. An attempt has been made to measure density, viscosity and ultrasonic velocity of aqueous solution of polyvinyl alcohol of molecular weight approximately 140,000 at different temperatures 35οC, 40oC, 45οC, 50oC, 55οC, 60oC, 65οC at 0.8% concentration. Ultrasonic velocity is measured using ultrasonic interferometer at 1 MHz frequency. The acoustical parameters like, adiabatic compressibility, acoustic impedance, intermolecular free length and relaxation time have been calculated at different temperatures. These parameters were used to understand the behaviour of solute and solvent.

Density, Viscosity and Ultrasonic Velocity of Polyethylene Glycol

Ultrasonic velocity, density, and viscosity of polyethylene glycol have been measured for the solution in water at concentration range of 0.3% to 1% at temperature 50oC. Ultrasonic velocity has been measured using ultrasonic interferometer at 1MHz frequency. By using the values of ultrasonic velocity, density, and viscosity, various acoustical parameters like adiabatic compressibility, acoustic impedance, intermolecular free length, and relaxation time have been calculated. The change in these acoustical parameters is explained in terms of solutesolvent interaction in a polymer solution.

A Comparison Study on Molecular Interaction of an Acidic Organophosphoric Extractant with Substituted Aromatic Hydrocarbon (p-xylene/toluene) at 303.15K

In the present study, the excess molar volume (VE) and the deviations in intermolecular free length (ΔLf), isentropic compressibility (Δβs), acoustic impedance (ΔZ), and ultrasonic velocity (ΔU) were calculated using the experimentally measured values of density (ρ) and ultrasonic velocity (U) of binary mixtures of an acidic organophosphoric extractant (DEHPA) with two substituted aromatic hydrocarbons, i.e., p-xylene and toluene at 303.15K and atmospheric pressure, 0.1MPa over the entire composition range of DEHPA. The results of both binary mixtures have been presented graphically and compared in terms of molecular interaction between unlike molecules of the mixtures, which outcome may be applied in the solvent extraction process.

Theoretical Values, Percentage Deviations and Calculated Values by Polynomials Equation’s of The liquid Mixture with Equimolar mixture of Ethanol and Formamide.

Background: The Binary mixtures of the isopropanol/isobutanol/isoamylalcohol with equimolar mixture of ethanol and formamide consists of different ultrasonic properties have been studied at room temperature at a fixed frequency of 2 MHz. The ultrasonic related physical parameters like velocity (U), density (ρ), adiabatic compressibility (βad), intermolecular free length (Lf) ,acoustic impedance (Z) etc. have been studied. The theoretical evaluation of ultrasonic velocity in liquid mixtures offers a transparent method for the study of the nature of molecular interactions in the mixtures besides verifying the applicability of different theories such as Nomoto’s, Van Dael and Vangeel’s, Impedance Dependence relation, Junjie’s relation, Rao’s specific sound velocity relation and Jacobson’s relations, Percentage deviations of theoretical ultrasonic velocities from experimental values in the mixtures of all liquid mixture and also calculated values of ultrasonic velocity from polynomials of for all the schemes with mole fraction (x) of isopropanol/isobutanol/isoamyl alcohol. Objective: The main focus of the present work was to prepare the structural changes associated with the liquid mixtures having weakly interacting components as well as strongly interacting components. The study of molecular is association in mixtures having exact information of thermodynamic mixing properties such as adiabatic compressibility, intermolecular free length, free volume, internal pressure and molar volume and has a great importance in theoretical and applied areas of research. The ultrasonic study has been a subject of active interest during the past many years. This branch of physical sciences has played a great role in deciding the interactions between the molecules of compounds under study not only that, but also it exists a potential tool in evaluating energy exchange between various degrees of freedom and nonlinear properties in binary liquid mixtures. Methods: The binary liquid mixtures were prepared by mixing the two components, by weight, using an electronic analytical balance (Reptech RA2012) accurate to within ±0.0001 g. The average uncertainty in mole fraction of binary mixtures was estimated to be ±0.0001. To avoid losses of solvent due to evaporation, mixtures were stored in specially designed ground-glass airtight ampoules and placed in a dark place to avoid photolytic effects. Results: These empirical fittings of data are described qualitatively and quantitatively using experimental speed data even in the specific interaction predominant region where non-ideal behavior of the mixture is observed. The values of sound velocities and percentage deviation, (after determining the co-efficient in the polynomial equations by applying least squares method) have been compiled in the tables respectively. Conclusion: The ultrasonic velocities and densities for all the three mixtures are measured and the values of are calculated from these values.The observed trends of and indicate the presence of weak interactions and the strength of these interactions follow the order EMM+IPA>EMM+IBA>EMM+IAA. Besides, the ultrasonic velocities gauge from different velocity theories are correlated with the experimentally measured ultrasonic velocities. Among these theories the Jacobson’s velocity equation gives good result between the experimental and theoretical ultrasonic velocity values for all the binary mixtures occupied.

Physico-chemical properties of binary systems involving modifier (methanol or propionic acid) and an acidic extractant di (2-ethylhexyl) phosphoric acid (DEHPA): volumetric, acoustic and viscometric routes

In solvent extraction, a suitable modifier, basically polar liquid is used with extractant like DEHPA, TBP, TOPO and MIBK to enhance the efficiency in extraction processes. This paper is related to the study of physico-chemical properties of polar – polar binary mixtures at 303.15K and 0.1 MPa. Molar volume, free volume, isentropic compressibility, intermolecular free length, specific acoustic impedance, relaxation time, Rao’s constant, Wada’s constant, absorption coefficient have been calculated from the experimentally measured data of density, ultrasonic velocity and viscosity of pure components and binary mixtures of methanol/ propionic acid + DEHPA. In addition, excess molar volume, excess Gibb’s energy of activation of viscous flow, deviations in viscosity, isentropic compressibility, free volume, intermolecular free length and acoustic impedance were also computed from the experimental data. The observed variations of excess/deviation functions with the composition of DEHPA have been discussed in terms of molecular interaction between unlike molecules in two binary mixtures due to chemical, physical and structural effects. It is found that the molecular interaction of methanol with extractant DEHPA is better than that of propionic acid and so methanol may be used as a suitable modifier with DEHPA in the solvent extraction process.