Gowrisankar M.,Jkc College |
Venkateswarlu P.,Sv University |
Siva Kumar K.,P.A. College |
Sivarambabu S.,Acharya Nagarjuna University
Journal of Industrial and Engineering Chemistry | Year: 2014
Measurement of densities (ρ), ultrasonic sound speeds (u) and viscosities (η) has been carried out for binary mixtures of N,N-dimethylaniline (N,N-DMA) with acetone(AC), methylethylketone (MEK), methylpropylketone (MPK), diethylketone (DEK), methylisobutylketone (MIBK), acetophenone (AP), cyclopentanone (CP), cyclohexanone (CH) and 2-methylcyclohexanone (MeCH) and their pure liquids at (303.15K and 308.15)K over the entire composition range. These experimental data have been used to calculate the excess molar volume (VE), deviation in ultrasonic sound velocity (δu), deviation in isentropic compressibility (δκs) and deviation in viscosity (δη) were evaluated. The variation of these properties with composition of the mixtures suggests dipole-dipole interactions and charge transfer complex formation between N,N-dimethylaniline and ketones. The magnitude of the property is found to depend on the chain length of the ketones molecule. These results have been fitted to the Redlich-Kister polynomial equation. The viscosity data have been correlated using three equations; Grunberg and Nissan, Katti and Chaudhri, Hind et al. for the system studied. © 2013 The Korean Society of Industrial and Engineering Chemistry.
Gowrisankar M.,Jkc College |
Venkateswarlu P.,Sv University |
Sivakumar K.,P.A. College |
Sivarambabu S.,Acharya Nagarjuna University
Journal of Solution Chemistry | Year: 2013
Densities, ρ, viscosities, η, and ultrasonic sound velocities u of pure methyl isobutylketone, diethylketone, cyclopentanone, cyclohexanone, 2-methyl cyclohexanone and those of their binary mixtures with N-methyl aniline were measured at 303.15 K over the entire composition range. These experimental data have been used to calculate the excess volume (V E), deviation in ultrasonic sound velocity (δu), isentropic compressibility (κ s ), intermolecular free length (L f), excess intermolecular free length (LfE L f E), acoustic impedance (Z), excess isentropic compressibility (κSEκ S E), deviation in viscosity (δη) and excess Gibbs energy of activation of viscous flow (G E). The viscosity data have been correlated using three equations proposed by Grunberg and Nissan, Katti and Chaudhri, and Hind et al. The excess/deviations have been fitted by Redlich-Kister equation and the results are discussed in terms of molecular interactions present in these mixtures. © 2013 Springer Science+Business Media New York.
Sreekala P.P.,Sv University |
Rao S.V.B.,Sv University |
Rajeevan M.,National Atmospheric Research Laboratory
Theoretical and Applied Climatology | Year: 2012
Rainfall over south peninsular India during the northeast (NE) monsoon season (Oct-Dec) shows significant interannual variation. In the present study, we relate the northeast monsoon rainfall (NEMR) over south peninsular India with the major oscillations like El Niño Southern Oscillation (ENSO), Indian Ocean Dipole (IOD), and Equatorial Indian Ocean Oscillation (EQUINOO) in the Indian and Pacific Oceans. For establishing the teleconnections, sea surface temperature, outgoing long wave radiation, and circulation data have been used. The present study reveals that the positive phase of ENSO, IOD, and EQUINOO favor the NEMR to be normal or above normal over southern peninsular India. The study reveals that the variability of NEMR over south peninsula can be well explained by its relationship with positive phase of ENSO, IOD, and EQUINOO. © 2011 Springer-Verlag.
Kiran N.,Sv University
Journal of Molecular Structure | Year: 2014
Sodium-lead borophosphate glasses doped with different concentrations of Eu3+ ion are prepared by using the melt quenching technique to study their physical, XRD FTIR and luminescence properties to understand the lasing potentialities of these glasses. The XRD studies confirm the amorphous nature of the glasses. FTIR spectrum indicates the presence of BO3 and PO 4 structural units. From the emission spectra, Judd-Ofelt (J-O) intensity parameters have been evaluated from the transition 5D 0 → 7FJ (J = 2 and 4). The evaluated (J-O) intensity parameters have been used to calculate the radiative transition probabilities, luminescence branching ratio and radiative decay times. The intensity ratio (R) value due to 5D0 → 7F2/5D0 → 7F 1 transition intensity of Eu3+ ions, increase with increasing concentrations suggesting higher asymmetry and covalent bonding character between rare earth ion and oxygen ligands. The chromaticity coordinates were calculated and analyzed with Commission International deI'Eclairage color diagram. The lifetimes of 5D0 metastable state for the samples with different concentrations were also measured and discussed. The predicted and experimental lifetimes for the 5D0 level in sodium lead borophosphate glasses were compared and discussed in detail. © 2014 Elsevier B.V. All rights reserved.
Babu S.,Sv University |
Balakrishna A.,Sv University |
Rajesh D.,Sv University |
Ratnakaram Y.C.,Sv University
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2014
Different metal oxide based fluoro-phosphate glasses doped with Sm 3+ ions are investigated using XRD, SEM with EDS, FTIR, Raman spectra, optical absorption and photo-luminescence techniques. These glass matrices have been prepared by conventional melt quenching technique. The glassy nature of the present glass matrices are confirmed by XRD profiles and SEM photographs. The composition of the glasses is checked by EDS. Based on FTIR and Raman spectra, the authors have analyzed functional groups that are present in the glass matrices. Judd-Ofelt intensity parameters, ωλ (λ = 2, 4, 6) have been evaluated from absorption spectra. Radiative parameters such as radiative transition probabilities (AR), radiative lifetimes (τR), integrated absorption cross sections (Σ) and branching ratios (βR) are calculated using Judd-Ofelt intensity parameters. From the photoluminescence spectra, experimental branching ratios (βexp) and stimulated emission cross-sections (σP) for all the observed emission transitions are calculated. To investigate luminescence potentiality of 4G5/2 → 6H7/2 emission level of Sm3+ doped different fluorophosphate glasses, experimental radiative lifetimes (τexp) are obtained from decay curve analysis for all glass matrices. Finally, these observed results are discussed and compared with the literature data. Crown Copyright © 2013 Published by Elsevier B.V. All rights reserved.
Basha D.C.,Sv University |
Rani M.U.,Sv University |
Devi C.B.,P.A. College |
Kumar M.R.,Sv University |
Reddy G.R.,Sv University
International Journal of Developmental Neuroscience | Year: 2012
Our earlier studies indicated the role of neurotransmitter systems in lead (Pb) induced behavioral perturbations. In this study, we examined the alterations in synaptosomal acetylcholine (ACh), epinephrine, dopamine, acetylcholinesterase (AChE), and mitochondrial monoamine oxidase (MAO) in the cerebellum and hippocampus of perinatally Pb-exposed rats. Rats (Wistar) were exposed to 0.2% Pb (Pb acetate in drinking water of mother) from gestational day 6 and the pups were exposed lactationally (through mother's milk) to Pb till weaning (postnatal day 21). Studies conducted on different postnatal days (PND 21, 28, 35 and 60) showed significant decreases in synaptosomal AChE and mitochondrial MAO activities, and increases in the levels of ACh, dopamine and epinephrine in the cerebellum and hippocampus of Pb-exposed rats. These alterations were greater at PND 35 and more pronounced in the cholinergic system (ACh and AChE) of hippocampus and the aminergic system (epinephrine, dopamine and MAO) of cerebellum. The total locomotor activity and exploratory behavior were also decreased significantly in Pb-exposed animals corresponding to the alterations observed in cholinergic and aminergic systems. Calcium administration together with Pb, however significantly reversed the Pb-induced alterations in transmitters and enzymes, as well as exploratory and motor behavior suggesting protective effect of calcium in Pb-exposed animals. © 2012 ISDN.
Sandeep N.,Vellore Institute of Technology |
Sugunamma V.,Sv University
Journal of Applied Fluid Mechanics | Year: 2014
We analyse the effects of radiation and rotation on unsteady hydromagnetic free convection flow of a viscous incompressible electrically conducting fluid past an impulsively moving vertical plate in a porous medium by applying inclined magnetic field, Under Boussinesq approximation, assuming that the temperature of the plate has a temporarily ramped profile. An exact solution of the governing equations, in dimensionless form is obtained by Laplace transform technique. To compare the results obtained in this case with that of isothermal plate and exact solution of the governing equations are also obtained for isothermal plate and results are discussed graphically in both ramped temperature and isothermal cases.
Kahleel Basha S.,Osmania college |
Sudarshanam G.,Sv University
International Journal of Phytomedicine | Year: 2010
In India, the use of different parts of several medicinal plants to cure specific ailments has been practiced since ancient times. Ehanobotanical studies were carried out to collect information on the use of medicinal plants by the tribal community (Sugalis) who live in the forests of Yerramalais of Kurnool district, Andhra Pradesh, India. The present paper deals with identification of 40 medicinal plants, with local names used by Sugalis for different diseases. The information about different types of medicinal plants used by them for various diseases recorded orally by interviewing the elders, Vaidyas (doctors) of that tribe by visiting their habitats called Thandas. Collected plants are stored in the Departmental Herbarium of Osmania College, Kurnool. Most of the medicinal plants are taken in as roots, tubers, stem and leaves, are taken orally with or without combination of other plants, external applications like paste, fumigation. Most of plants used by them are Herbs (42%), shrubs (20%), Trees (33%).and Climbers (5%) The most striking feature of tribal life is their simplicity. The forest is able to provide them with everything. Professionally they are peasants, food-gatherers, hunters, small farmers, and, nomads. Sugalis use medicinal plants mainly for viral fevers, skin deceases, snake & scorpion bites and stomach problems. It is observed that the urban educated people are more aware of good effects of herbal medicine over allopathic medicine than the rural people. Due to the degraded forests and depleted resources, they are migrating to urban areas for livelihood. So there is a danger of losing knowledge of medicinal plants for human welfare. Hence there is an urgent need to document and popularize the value of herbal medicine among the rural people through Vana Samrakhak Samithi and other agencies. © arjournals.org, All rights reserved.
Reshma Anjum M.,Sv University |
Sreenivasula Reddy Dr. P.,Sv University
International Journal of Pharma and Bio Sciences | Year: 2013
To asses whether prenatal exposure to lead induces testicular oxidative status at adulthood, pregnant Wistar rats were exposed to an ad libitum drinking water containing lead acetate at 0.05% and 0.15% respectively, throughout their pregnancy period. All the animals were allowed to deliver pups. Lead exposure was continued throughout the lactation period. Weaned pups were allowed to grow on normal diet and tap water (free from lead) and on postnatal day 100, animals weresacrificed, testes was isolated and analyzed for lipid peroxidation. Significant increase in the lipid peroxidation levels were observed in the testis of lead exposed rats when compared with controls. Significant decrease in the activity levels of antioxidant enzymes: superoxide dismutase and catalase in the testes were observed in the testis of lead exposedrats. From the results it can be concluded that perinatal exposure to lead induces oxidative stress in the testis of rats at adulthood.
Rama Mohan K.,Sv University |
Achari V.B.S.,Sv University |
Rao V.V.R.N.,Sv University |
Sharma A.K.,Sv University
Polymer Testing | Year: 2011
Sodium ion conducting polymer blend electrolytes based on poly (vinyl chloride)/poly (ethyl methacralyte) complexed with NaClO4 were prepared using a solution casting technique. The features of complexation of the electrolytes were studied by X-ray diffraction (XRD). DC conductivity of the films was measured in the temperature range 303-398 K. The electrical conductivity increased with increasing dopant concentration, which is attributed to the formation of charge transfer complexes. The polymer complexes exhibited Arrhenius type dependence of conductivity with temperature. In the temperature range studied, two regions with different activation energies were observed. Transference number data showed that the charge transport in this system is predominantly due to ions. Electrochemical cells of configuration Na/(PEMA + PVC + NaClO4)/(I2 + C + electrolyte) were fabricated and the discharge characteristics of these cells were studied under a constant load of 100 KΩ. Several cell parameters associated with the cells were evaluated and compared with earlier reports. Optical properties such as absorption edge, direct band gap and indirect band gap were estimated for pure and doped films from their optical absorption spectra in the wavelength region 200-600 nm. It was found that the energy gap and band edge values shifted to lower energies on doping with NaClO4 salt. © 2011 Elsevier Ltd. All rights reserved.