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1

Thermodynamic Interactions of P-Chlorotoluene with P-Xylene at 303.15 K, 308.15 K, 313.15 K and 318.15 K

Kumar G. P., Babu C. P., Samatha K.

International Letters of Chemistry, Physics and Astronomy

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2015

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Vol. 52

53--62

EN

Ultrasonic velocity, density and viscosity of the binary liquid mixtures of P-Chlorotoluene with p-xylene over the whole composition range at 303.15, 308.15, 313.15 and 315.15 K at frequency 2 MHz have been measured. Acoustical parameters such as adiabatic compressibility, intermolecular free length, impedance, molar volume, internal pressure, free volume, Rao constant and Wada constant. The acoustical parameters can be used to assess the strength of induced dipole-dipole interactions in this system studied.

2

Comparative Study of Experimental and Theoretical Ultrasonic Velocities in Binary Mixtures of Cyclohexanone with Aliphatic Esters at Different Temperatures

Divakar P. P., Samatha K.

International Letters of Chemistry, Physics and Astronomy

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2015

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Vol. 42

13--24

EN

Ultrasonic velocity evaluated by various theoretical relations viz., Nomoto, Free Length Theory (FLT), Van deal and Vangeel ideal mixing relation (IMR), Impedance Dependence Relation (IDR), and Junjie in three binary liquid mixtures of cyclohexanone as a common component with aliphatic esters (isopropyl acetate, isobutyl acetate and isoamyl acetate) at 303, 308, 313 and 318K over the entire composition range. An attempt has been made to compare the merits of the relations and the relative applicability of these theories to the present systems have been checked and discussed. The results are explained in terms of intermolecular interactions occurring in these binary systems. The deviation in the variation of U2exp / U2 imx from unity has also been evaluated for explaining the non-ideality in the mixtures.

3

Aqueous Solution and Computed Gas Phase Properties of Meclofenamic Acid Sodium Salt

Kharat S.J.

International Letters of Chemistry, Physics and Astronomy

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2015

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Vol. 41

124--131

EN

Paper reports densities, ultrasonic velocities, and refractive indices of aqueous solutions of meclofenamic acid sodium salt (Na-MCF). Densities, ultrasonic velocities, and refractive indices have been measured at (298.15, 303.15, 308.15, and 313.15) K and at atmospheric pressure. Limiting molar volume and limiting molar isentropic compressibility have been calculated. DFT method has been used for computation of dipole moment, free energy, hydration free energy, and HOMO and LUMO energies of Na-MCF. Gas phase properties have been computed by the use of G09 W Software.

4

Acoustical studies on molecular interaction of 1,3,4-pyrazoline derivatives using ultrasonic technique at 303.15 K

Santhi A. R. N.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 20, iss. 1

100--115

EN

The acoustical parameters for the binary liquid mixtures containing Pyrazoline derivatives in DMF have been estimated at 303.15 K, from the measured values of ultrasonic velocity (U), density (ρ) and viscosity (η). From these data some of acoustical parameters such as adiabatic compressibility (β), free length (Lf), acoustic impedance (Z), Rao’s constant (R), molar compressibility (W), relaxation time (τ), free volume (Vf) and internal pressure (πi), etc., have been computed using the standard relations. The results have been discussed in terms of molecular interactions.

5

Acoustical studies of some synthesized Schiff base derivatives in dimethylsulphoxide at 303.15 K, by ultrasonic velocity measurement

Gopi C., Santhi N.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 17, iss. 1

50--66

EN

The density, viscosity and sound velocity of five Schiff bases (1-5) derivatives in DMSO solutions have been studied at 303.15 K over a wide range of concentration. From these experimental data, some acoustical parameters such as Molar volume (Vm), Specific Acoustic Impedance (Z), Adiabatic compressibility (βad), Intermolecular Free Length (Lf), Rao’s Constant (R), Molar compressibility (W), Relaxation time(τ), van der Waals constant (b), Relaxation strength (r), Relative association (RA), Isothermal compressibility (βT ) , Isothermal expansion co-efficient (α) ,Free volume (Vf) and Internal pressure (πi) and Ultrasonic attenuation (α/f²) have been evaluated. A fairly good correlation between a given parameter and concentration is observed. The results are interpreted in terms of molecular interactions like solvent-solvent, solvent-solute and solute-solute interactions.

6

Acoustical studies of binary liquid mixtures of p-chlorotoluene in benzene at different temperatures

Kumar G. P., Babu Ch. P., Samatha K, Jyosthna A. N., Showrilu K.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 10

25--37

EN

Ultrasonic velocities (U), densities (ρ), and coefficient of viscosities (η) are measured for binary mixtures containing (i) p-chlorotoluene and (ii) benzene at 303.15 K, 308.15 K, 313.15 K and 318.15 K to understand the molecular interaction. Various acoustical parameters such as adiabatic compressibility (βad), free length (Lf), acoustic impedance (Z), free volume (Vf), molar volume (Vm), Rao’s constant (R), Wada’s constant (W) and internal pressure (πi), are calculated from the measured values of U, ρ, and η. The trend in acoustical parameters also substantiates to asses strong molecular interactions.

7

Theoretical ultrasonic velocities in binary liquid mixture containing aniline and anisole at different temperatures – a comparative study

Sreedevi Y., Srinivasu Ch., Fakruddin Sk., Narendra K., Venkateswara Rao B.R., Nirmal Rajeev Y.

International Letters of Chemistry, Physics and Astronomy

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2013

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Vol. 7, iss. 2

120--124

EN

Ultrasonic velocity is measured experimentally at 3MHz frequency in the binary liquid mixture containing aniline and anisole at different temperatures over the entire composition range and theoretical values of ultrasonic velocity have been evaluated by using Nomoto’s relation, Impedance relation, Van Dael ideal mixture relation. These theoretical values are compared with the experimental values. A good agreement has been found between experimental and theoretical ultrasonic velocities.

8

Theoretical evaluation of ultrasonic velocities in binary liquid mixtures at different temperatures

Bhavani M.D., Ratnakar A., Kavitha Ch.

International Letters of Chemistry, Physics and Astronomy

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2013

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Vol. 5

1-6

EN

Ultrasonic velocities calculated from various theories and relations like Nomoto's relation, Van dael ideal mixing relation, Impedance relation, Rao's specific velocity relation and Jungie's theory are compared with experimental values in binary liquid mixtures o-anisidine with o-cresol at temperatures 303.15, 308.15, 313.15 and 318.15 K over the entire mole fraction range. The relative applicability of these theories to the present system is checked and discussed. A good agreement is observed between experimental and theoretical values. The results are explained in the light of molecular interactions occuring in these mixtures.

9

Study of acoustical parameters in binary liquid mixture containing 1-butanol and hexane at temperatures 313.15 K, 318.15 K and 323.15 K

Srinivasu C. H., Kumar A. K., Fakruddin S. K., Narendra K., Anjaneyulu T.

International Letters of Chemistry, Physics and Astronomy

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2013

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Vol. 13

1-7

EN

The values of ultrasonic velocity (u), density (ρ), and viscosity (η) have been measured experimentally in the binary liquid mixture containing 1-butanol and hexane over the entire range of composition at different temperatures 313.15 K, 318.15 K and 323.15 K. This experimental data have been used to calculate the acoustical parameters such as adiabatic compressibility (β), free length (Lf), molar volume (Vm) and acoustic impedance(z). The results have been qualitatively used to explain the molecular interactions between the components of the liquid mixture.

10

Studies of densities, viscosities and ultrasonic speeds of binary mixtures containing isopropyl alcohol and ketones at different temperatures

Srinivas S. S. J., Tulasi Koteswari Bai B., Babu Rao K., Narendra K., Sarath Babu M.

International Letters of Chemistry, Physics and Astronomy

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2013

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Vol. 10, iss. 2

151-158

EN

The densities, viscosities and ultrasonic velocities of binary liquid mixtures of Isopropyl alcohol with acetophenone and methyl isobutyl ketone (MIBK) have been measured at temperatures 298.15 and 308.15 K over the entire range of mole fraction. From these data, acoustical parameters such as adiabatic compressibility (β), free volume (Vf) and free length (Lf) have been estimated using the standard relations. The results are interpreted in terms of molecular interactions present in the mixtures.

11

Structure and Ultrasonic Properties of Vanadium Tellurite Glasses Containing Copper Oxide

Abd El-Aal N. S., Afifi H. A.

Archives of Acoustics

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2009

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Vol. 34, No. 4

641-654

EN

The elastic properties of vanadium tellurite glasses, 65TeO2-(35-x) V2O5-xCuO, with different compositions of Copper (x = 7.5 to 17.5 mol% in steps of 2.5 mol%) have been studied at room temperature (300 K). The ultrasonic velocity measurements have been made, using a transducer having resonating frequency of 4 MHz (both longitudinal and shear). The density, molar volume, and ultrasonic velocities show interesting features, which are used to explore the structural changes in the network. Elastic moduli, Poisson ratio, crosslink density, Microhardnes, and Debye temperature of the glasses have been determined using the experimental data. The composition dependence of the elastic properties explores useful information about the physical properties of the vanadium tellurite glasses doped with Copper. Quantitative analysis has been carried out in order to obtain more information about the structure of the glass under the study, based on bond compression model and the Makishima & Mackenzie model. The observed results through ultrasonic nondestructive evaluation, investigate the structural changes and mechanical properties of the glass.

12

Acoustic Spectroscopy,Experimental Methods and Research

Linde B.

Molecular and Quantum Acoustics

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2006

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Vol. 27

169-188

EN

There was presented in the paper the theoretical discussion about the ultrasonic relaxation process related to energy transfer between translational and vibrational degrees of freedom as well as with the existing of chemical isomerism. The part of the paper describes several ultrasonic equipments for measurements of absorption and velocity in very wide frequency range from hundreds kHz to tens GHz. At the end there were shown several experimental examples of possible taking the advantage of the ultrasonic spectroscopy.

13

Results of Ultrasonic Velocity and Density Investigations of the Nematic Liquid Crystal

Balcerzak A.

Molecular and Quantum Acoustics

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2004

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Vol. 25

17-22

EN

Velocity of ultrasonic longitudinal waves in the nematic liquid crystal 1-(trans-4- hexylcyclohexyl)-4-isothiocyanatobenzene (6CHBT) has been measured as a function of temperature between 24oC and 55oC at 5.2 MHz. The temperature dependence of velocity shows a local minimum in the region of the nematicisotropic (N-I) phase transition. Additional temperature measurements of density have been done to calculate the thermal coefficient of expansion and the temperature coefficient of adiabatic compressibility. Both these parameters exhibit critical behaviour at the transition which has been analysed. The values of the exponent determining the growth of the order fluctuations have been calculated and compared with references.

14

The estimation of structural anisotropy of trabecular and cortical bone tissues based on ultrasonic velocity and attenuation

Trębacz H., Gawda H.

Acta of Bioengineering and Biomechanics

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2001

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Vol. 3, nr 2

41-48

EN

Velocity of ultrasound and broad-band ultrasound attenuation (BUA) were measured in three perpendicular directions in anisotropic samples of cancellous and cortical bones. The aim was to study tte influence of microarchitecture of bone tissue on ultrasound propagation in bone. The pulse transmission method (1 MHz and 3.5 MHz) and the Fourier analysis of transmitted were applied. The dependence of both ultrasonic parameters on the orientation and the correlation between the degree of the anisotropy and bone density were stated. In cancellous bone samples, both velocity and BUA had extreme value in the direction of trabeculae alingment. In cortical bone, maximal velocity was in the axial direction, while BUA in this direction was minimal. The influence of the anisotropy of bone structure, both cancellous and cortical, on ultrasonic parameters is discussed.

15

Badania własności struktury kości gąbczastej z zastosowaniem metod spektroskopii elektrycznej i metody ultradźwiękowej

Łukowski J., Pakuła M., Kaczmarek M.

Zeszyty Naukowe. Mechanika / Akademia Techniczno-Rolnicza w Bydgoszczy

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2000

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Z. 47 (228)

165-173

PL

Kości są materiałami o anizotropowych własnościach mechanicznych i strukturalnych. Główne kierunki anizotropii tych materiałów związane są z obciążeniami, jakimi są poddawane w warunkach fizjologicznych. Badania własności mechanicznych pokazują, że najczęściej materiały kostne charakteryzują się transwersalną izotropią lub ortotropią. Celem niniejszej pracy było wyznaczenie i analiza parametrów anizotropowej struktury kości gąbczastej. tj. współczynnika uformowania oraz krętości w oparciu o pomiary przewodności elektrycznej i porównanie relacji pomiędzy zmierzonymi parametrami struktury a prędkością propagacji podłużnej fali ultradźwiękowej. Do wyznaczenia parametrów struktury wykorzystano metodę dwuelektrodową z zastosowaniem mostka RLC oraz układu umożliwiającego pomiar przewodności metodą techniczną w zakresie częstotliwości od 100 HZ do 100 kHz. Materia� badany stanowiły sześcienne próbki gąbczastej kości wołowej o wymiarze boku ok. 10 mm uzyskane z głowy kości udowej i kręgów kręgosłupa. Pomiary przewodności przeprowadzono dla materiału zawierającego szpik kostny - nasyconego płynem fizjologicznym, w trzech wzajemnie prostopadłych kierunkach.

EN

Bones are materials with anisotropic mechanical and structural properties. The paper investigates parameters of anisotropic structure of trabecular bone: formation factor and tortuosity using measurements of electric impedance and a comparison between the structure parameters measured and velocity of ultrasonic wave propagation. To determine the material impedance, the two-electrode method with RLC bridge and direct technique are applied. The cubic specimens (1 cm x l cm x l cm) of trabecular bovine bone are cut from the distal epiphysis of fresh bovine femora and vertebra. The results show a good correlation between tortuosity measured by electric spectroscopy and velocity of longitudinal waves.