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U. Sridevi ¹, K. Samatha ¹, A. Viswanatha Sarma ¹

Affiliations
1 Ultrasonic Research Laboratories, Department of Physics, Andhra University, Visakhapatnam, IN

Abstract

Ultrasonic velocity and viscosity have been determined in three binary liquid mixtures (i.e.) O- chloroaniline+O-chlorophenol, N, N-Diethyl aniline+O-chlorophenol, N, N-Diethyl aniline+O-cresol at 34°C, 37°C, 40°C and 43°C in the entire composition range. Excess adiabatic compressibilities and excess volumes have been evaluated and found to be negative in the mixtures. Excess compressibilities (experimental) have been compared with the theoretical excess compressibilities as suggested by Barker. The agreement is found to be good. The results are interpreted in the light of molecular association to the hydrogen bonding.

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J. Viswanadha Sastry ¹, K. Samatha ¹, A. Viswanatha Sharma ¹

Affiliations
1 Ultrasonic Research Laboratories, Department of Physics, Andhra University, Visakhapatnam-530003, IN

Abstract

Ultrasonic velocity density, viscosity, in binary mixtures of m-cresol+quinoline, at 18°C, 24°C and 32°C, m-cresol+phenylhydrazine and o-chlorophenol+phenylhydrazine at 32°C, 38°C and 45°C are measured over the entire range of composition. From the experimental data other related thermodynamic parameters, viz., adiabatic compressibility, intermolecular free length, excess volume, excess adiabatic compressibility, excess viscosity, Rao's constant and Wada's constant are calculated. The deviation from ideality of these parameters is explained on the basis of molecular interaction between the constituent of the mixtures.

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V. Naveen Kumar ¹, P. S. Brahmanandam ², M. Purnachandra Rao ³, G. Anil Kumar ⁴, K. Samatha ³, L. Rupa Dhanasri ⁵

Affiliations
1 Department of Basic Science, Gudlavalleru Engineering College, Gudlavalleru - 521356, Andhra Pradesh, IN
2 Departmentof Basic Science, Shri Vishnu Engineering College for Women, Bhimavaram - 534202, Andhra Pradesh, IN
3 Departmentof Physics, Andhra University, Visakhapatnam - 530003, Andhra Pradesh, IN
4 School of Renewable Energy and Environment, JNTUK, Kakinada - 533003, Andhra Pradesh, IN
5 Department of ECE, Shri Vishnu Engineering College for Women, Bhimavaram - 534202, Andhra Pradesh, IN

Abstract

Objectives: Although several methods are available to identify ABLHeight (ABLH), a comprehensive study on the usage of different analytical methods has not been reported widely, particularly on global databases. Methods/Analysis: In this research, we use various analytical methods including, gradient, double gradient and logarithmic gradient to estimate ABLH during two months (March and April 2013) period and applied those methods on COSMIC Radio Occultation retrieved temperature profiles to estimate ABLH. Findings: The estimated ABLHs are arranged in order to present them globally and diurnally that clearly show a few distinct features. Mainly, land and desert areas are associated with higher ABLH during daytime hours. Cold land areas (Arctic and Greenland) show relatively lower magnitudes and reverse are the cases with ABLH over cold oceans (Antarctic oceans). Most importantly, a distinctive diurnal feature is observed with a peak at sharp noon time and relatively lower values in the night time, which indicate both convective and stable layers, have evolved based on the ambient conditions that would exist during the day and nighttime ambient conditions. However, morning and evening transitions are not found in diurnal variations. Applications/Improvements: It is found that both gradient and logarithmic methods are able to find accurate ABLH, though still a great room exists to verify various other methods in finding ABLH.

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