G. Srinivasa Rao

Thermo physical properties and IR spectra of 2-chloroethanol and 2-phenylethanol in N-methyl-2-pyrrolidone at different temperatures and 101.3 kPa

ABSTRACT The interactions of 2-chloroethanol (2-CE) and 2-phenylethanol (2-PE) in N-methyl-2-pyrrolidone (NMP) as a function of temperature have been investigated. The density (ρ), and ultrasonic velocity (u), of 2-CE and 2-PE in NMP have been measured in the temperature interval T = (303.15, 308.15, 313.15 and 318.15) K and atmospheric pressure. The excess molar volume, excess partial molar volume, excess partial molar volume at infinite dilution and excess isentropic compressibility of 2-CE and 2-PE in NMP binary liquid solutions were determined at measured temperatures. The calculated excess functions , and were fitted to Redlich–Kister equation to estimate binary interaction parameters. The excess functions have been discussed in terms of molecular interactions between component molecules of the binary mixtures and their interacting abilities were compared. Infrared spectroscopy (FT-IR) measurements have also been done to explain the molecular interaction in the binary liquid mixtures.

Theoritical Evaluation of Ultrasonic Velocities in Binary Liquid Mixtures of N-Methyl-2-pyrrolidone at Different Temperatures with Some Cyclic Compounds

Ultrasonic velocities and densities of the binary liquid mixtures of N-methyl-2-Pyrrolidone (NMP) with Cyclohexylamine (CHA), Cyclohexanol (CHOL) and Cyclohexene(CHE) at a temperature range of 303.15 to 318.15 K over the entire composition range were measured. The theoretical values of ultrasonic velocity were evaluated using the Nomotos relation(UNR), Impedence relation(UIR), Ideal mixing relation(UIMR), Jungies relation(UJR) and Raos specific velocity relation(UR).The molecular interaction parameter (α) was computed by using the experimental and theoretical ultrasonic velocity values. The variation of interaction parameter with the composition of the mixture has been discussed in terms of molecular interactions.

The spectroscopic investigations on Ni2+ ions in PbO-As2O3 glasses

PbO-As2O3 glasses containing different concentrations of NiO ranging from 0 to 1 mol% (in steps of 0.2) were prepared. The optical absorption and thermoluminescence have been carried out on these glasses. The analysis of the optical absorption spectra indicates the presence of Ni 2+ ions in both tetrahedral and octahedral positions. The increase in the concentration of NiO in the glass matrix shows a gradual transformation of nickel ions from tetrahedral positions to octahedral positions in the glass network. TL light output of the X-ray irradiated glasses has exhibited a glow peak at 353 K in addition to the conventional peak due to the recombination of electron-hole centres; this glow peak is identified due to 3 T2→ 3 A2 emission transition of octahedral Ni 2+ ions. The present study indicates an increasing presence of octahedral (lasing) Ni 2+ ions in these glasses with the concentration of NiO.