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Tirunelveli, India

Sivagurunathan A.,The MDT Hindu College | Xavier Innocent B.,St Xaviers College | Muthu Lakshmi S.,The MDT Hindu College
Journal of Applied Pharmaceutical Science | Year: 2012

The present study was carried out to evaluate the immunostimulant potential of Nelumbo nucifera (Lotus). Formulated diets with different concentrations of ethanolic extract of N.nucifera (D1=0%, D2=1% and D3=2%) were fed to Cirrhinus mrigala for 40 days, the Specific Growth Rate (SGR) and Feed Conversion Ratio (FCR) were calculated significant increase was observed in SGR &FCR. Then the experimental fishes were infected with Pseudomonas aeruginosa and after 5 days the haematological parameters like Total Erythrocyte count (TEC), Haemoglobin (Hb), Total leucocyte count (TLC), Differential leucocyte count (DLC), serum total protein, serum albumin and globulin levels were analyzed. The TEC, Hb, TLC, Lymphocytes and monocyte counts increased significantly in D3 diet fed fishes. Highly significant increase was observed in serum total protein and albumin levels only. Globulin levels remain unchanged. Basophil and Eosinophil counts decreased significantly. Thus N.nucifera in fish feed preparations may be included as growth promoter and immunostimulator.

Subramanian S.,The MDT Hindu College | Balaji M.,Manonmaniam Sundaranar University | Chithra Lekha P.,Manonmaniam Sundaranar University | Asokan K.,Inter University Accelerator Center | And 4 more authors.
Current Applied Physics | Year: 2010

Sb2S3 thin films prepared by electrodeposition on indium tin oxide coated glass substrate were irradiated with 150 MeV Ni11+ ions for various fluence in the range of 1011-1013 ions/cm2. The modifications in the structure, surface morphology and optical properties have been studied as a function of ion fluence. X-ray diffraction (XRD) analysis indicates a shift in the (2 4 0) peak position towards lower diffraction angle and a decrease in grain size with increase in ion fluence. Presence of microcracks due to irradiation induced grain splitting effect has been observed from the SEM micrograph at higher ion fluence. The optical absorbance spectrum revealed a shift in the fundamental absorption edge and the band gap energy increased from a value of 1.63 eV for as-deposited films to 1.80 eV for the films irradiated with 1013 ions/cm2. © 2010 Elsevier B.V. All rights reserved.

Chithra Lekha P.,Manonmaniam Sundaranar University | Subramanian S.,The MDT Hindu College | Philip J.,Cochin University of Science and Technology | Pathinettam Padiyan D.,Manonmaniam Sundaranar University
Physica B: Condensed Matter | Year: 2010

Polyaniline (PAni) doped with dodeca tungstophosphoric acid (12TPA) nanomaterials prepared by interfacial polymerization are characterised via UVvis spectroscopy, X-ray diffraction, thermogravimetry and ac impedance analysis. From the X-ray diffraction pattern, the crystallite size of the nanomaterials is found to be around 10-50 nm. The ac impedance studies on these materials in the temperature range 300-398 K show that the conductivity in PAni is due to the hopping of polarons following correlated barrier hopping model whereas in PAni doped with 12TPA (P12TPA) it is due to the tunneling of large polarons. It gives an understanding on the role of thermal annealing over the conductivity of the P12TPA, which arises from the presence of hydroxyl groups and is also evident from the thermogram. The humidity sensing behaviour of the nanomaterial elucidates the P12TPA as a good humidity sensor. The results of optical, structural and thermal analysis illustrate that PAni and 12TPA are not simply blended or mixed up, but a strong interaction is there between the polymer backbone and the polyanion. © 2010 Elsevier B.V. All rights reserved.

Chithra lekha P.,Manonmaniam Sundaranar University | Subramanian S.,The MDT Hindu College | Yi J.,Sungkyunkwan University | Dhanuskodi S.,Bharathidasan University | Pathinettam Padiyan D.,Manonmaniam Sundaranar University
Materials Chemistry and Physics | Year: 2010

The electrochemically prepared polyaniline-12-molybdophosphoric acid (P12MPA) thin films in conducting emeraldine salt form of polyaniline (PAni) matrix is verified by the presence of redox peaks in the UV-vis spectra for different dopant concentrations. The optical band gap energy in these films is dopant concentration dependant and tunable. From the FTIR spectra, it is evidenced that, the characteristic peaks of PAni is present in P12MPA thus there is only conformational change due to the inclusion of molybdophosphoric acid (12MPA) in the polymer matrix. The amorphous nature of the film is proved from the XRD. XPS peaks of PAni and P12MPA thin films have shown the evidence for the presence of quinoid imine, benzenoid amine and the polaronic nitrogen and the oxidation level is quantitatively analysed. P12MPA has the oxidation level of around 51% which matches with that of protonated emeraldine form. Due to the inclusion of 12MPA, in addition to para coupling of the monomer, ortho coupling also takes place. Impedance analysis shows the role of temperature in crosslinking of polymer chain and dopant anions. The high response of P12MPA (64.8%) towards acetone vapor provides evidence for improved sensing behaviour of the doped polymer. © 2010 Elsevier B.V. All rights reserved.

Chithra lekha P.,Manonmaniam Sundaranar University | Balaji M.,Manonmaniam Sundaranar University | Subramanian S.,The MDT Hindu College | Pathinettam Padiyan D.,Manonmaniam Sundaranar University
Current Applied Physics | Year: 2010

The polyoxomolybdates encapsulated PAni hybrid materials are prepared by interfacial polymerisation. In P12MPA, the crystal structure of 12MPA is not modified on doping with PAni. However, P11MPA have the polycrystallinity due to the presence of vanadium in the dopant molecule. Though, the hybrids prepared by interfacial polymerisation are in emaraldine salt form, there is a blue shift in the absorption spectra due to dopant induced decrease in conjugation length and over-oxidation. Interfacially polymerised PAniPOM hybrid materials are exposed with various concentrations of vapours of different volatile organic compounds (VOC) such as acetone, methanol, chloroform and carbon tetrachloride. The oxidising VOCs like acetone and methanol on exposure to PAni decrease the resistivity by hydrogen bonding with the redox cites of the polymer. Among these two, the sensitivity towards acetone is more in PAni and its hybrids which can be linked with the vapour pressure of the analyte. Due to the weak acidic characteristics of chlorinated hydrocarbons which are reducing vapours, the resistivity of PAni and its hybrids increases on exposure to chloroform and CCl4. Here, the chlorinated hydrocarbons interact with the redox sites of PAni and reduce it to base form. Bridging of polymer chains is also proposed for the reduction of conductivity on exposure to the analyte. The sensitivity is higher for the reducing analytes than that of the oxidising one. © 2009 Elsevier B.V. All rights reserved.

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