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Acustical studies of interactions in the binary mixtures of ethylmethyl ketone (EMK) and N,N-dimethylformamide (DMF) through ultrasonic measurements at different temperatures

Patial B. S.

International Letters of Chemistry, Physics and Astronomy

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2015

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Vol. 47

120--132

EN

Ultrasonic velocities (u), densities (ρ) and viscosities (η) are measured in respect of ethylmethylketone (EMK) and N,N-dimethylformamide (DMF) over the entire composition at 298, 308and 318K. Attempt have been made to extract the information with respect to various kind of intermolecular interactions, such as H-bonding, dipole-dipole, solute –solvent, dispersion type interactions existing between these two components from the following acoustical parameter when examined as a function of solvent composition at different temperatures: adiabatic compressibility (β), specific acoustic impedance (Z), intermolecular free length (Lf), molar sound velocity (Rm), wada’s constant (W), viscous relaxation time (τ), free volume and internal pressure (πi).

2

Theoretical evaluation of ultrasonic velocities of binary liquid mixtures of 1-bromopropane in chlorobenzene at 303.15, 308.15, 313.15 and 318.15 K

Babu Ch. P., Kumar G. P., Nagarjun B., Samatha K.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 11, iss. 1

9-17

EN

Theoretical velocities of binary liquid mixtures of 1-bromopropane with chlorobenzene at 2 MHz and four different temperatures 303.15, 308.15, 313.15 and 318.15 K, have been evaluated as a function of concentration and temperature. The experimental values are compared with theoretical models of liquid mixtures such as Nomoto, Van Dael-Vangeel, Impedance Relation, Rao’s Specific Velocity Method, Junjie’s relations and Free Length Theory. In the chosen system there is a good agreement between experimental and theoretical values calculated by Nomoto’s theory. The deviation in the variation of U2exp/ U2imx from unity has also been evaluated for explaining the non ideality in the mixtures. The results are explained in terms of intermolecular interactions occurring in these binary liquid mixtures.

3

Numerical support of laboratory experiments: Attenuation and velocity estimations

Saenger E., Madonna C., Almqvist B.

Acta Geophysica

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2014

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Vol. 62, no. 1

1--11

EN

We show that numerical support of laboratory experiments can significantly increase the understanding and simplify the interpretation of the obtained laboratory results. First we perform simulations of the Seismic Wave Attenuation Module to measure seismic attenuation of reservoir rocks. Our findings confirm the accuracy of this system. However, precision can be further improved by optimizing the sensor positions. Second, we model wave propagation for an ultrasonic pulse transmission experiment used to determine pressure- and temperature-dependent seismic velocities in the rock. Multiple waves are identified in our computer experiment, including bar waves. The metal jacket that houses the sample assembly needs to be taken into account for a proper estimation of the ultrasonic velocities. This influence is frequency-dependent.