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S. Babu ¹, K. Seetharaman ¹, R. Nandakumar ¹, I. Johnson ¹

Affiliations
1 Department of Plant Pathology, Tamil Nadu Agricultural University Coimbatore 641 003, Tamil Nadu, IN

Abstract

Fungal antagonists were tested in vitro against the growth of the pathogen Altemaria solani (Ell. and Mart.), and in tomato plants against the leaf blight disease. Although Trichoderma harzianum followed by T. viride were significantly effective in inhibiting the mycelial growth or A. solani. there was no significant difference between the effcctiveness of Trichoderma species in pot culture studies.

Keywords

Antagonist, Alternaria solani, Tomato Leaf blight, Trichoderma.

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Rintu Varghese ¹, H. Joy Prabu ¹, I. Johnson ¹

Affiliations
1 Centre for Nanoscience and Applied Thermodynamics, Department of Physics, St. Joseph's College, Trichy-620002, IN

Abstract

Reduced graphene oxide (rGO) is a radical candidate for energy related sector. In this paper, we report how few layers graphene that can be produced in large quantity with low defect ratio from exfoliation of GO by using a sonication energy. GO was prepared from graphite powder by modified Hummer's method. GO then further exfoliated to graphene oxide by using ultrasonic irradiation.The ultrasonication approach for the exfoliation of rGO nanosheet is relatively fast, cost-effective and efficient as compared to other methods.The characterization techniques such as UV and FT-IR analysis confirmed the reduction of GO to rGO. The structure and morphology of as-prepared rGO nanosheet were studied using a range of techniques such as XRD, Raman spectroscopy, SEM, and TEM.The experimental results suggest that the graphene sheets obtained by this simple exfoliation method after the heat reduction had an excellent exfoliation into a few layered graphene sheets.

Keywords

Ultrasonication, rGO, XRD, Electron Microscopy.

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A. J. Clement Lourduraj ¹, I. Johnson ¹

Affiliations
1 Department of Physics, St. Joseph's College (Autonomous), Trichirappaali - 620 002, IN

Abstract

This paper reports the experimental densities, sound velocities and viscosities of the binary mixtures of Cyclohexanone with Hexane and Heptane respectively, which have been measured at 308.15Kfor the entire range of mole fraction. From these data, excess volume (V^E) have been calculated. Experimental and computed results are used to study the type and nature of inter and intra molecular interactions between the mixing components. Even though these types of studies exist in the literature there is no confirmation for the observed excess properties through other non-ultrasonic techniques. For the confirmation of the excess properties FTIR spectra have been taken for various compositions. This FTIR study gives supportive evidences for the results obtained through the excess properties.

Keywords

Ultrasonic Velocity, Excess Volume, Cyclohexanone, FTIR Spectrum, Dipole Induced Dipole-Interaction.

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I. Johnson ¹, A. J. Clement Lourduraj ¹

Affiliations
1 Department of Physics, St Joseph's College, Trichy-620002, IN

Abstract

A deeper knowledge of mixing properties of multi component liquid systems is essential in many industrial applications, such as design calculation, mass transfer, fluid flow etc. This paper reports the experimental densities, sound velocities and viscosities of the binary mixture 2-Ethoxy ethanol+Dimethyl sulfoxide which have been measured at 308.15K for the entire range of mole fraction. From these data, excess volume V^E, deviations in adiabatic compressibility Δβ_a, viscosity Δη and ultrasonic velocity Δu have been calculated. Experimental and computed results are used to study the type and nature of inter and intra molecular interactions between the mixing components. Even though these type of studies are existing in the literature there is no confirmation for the observed excess properties through other non ultrasonic techniques. For the confirmation of the observed excess properties FTIR spectra have been taken in the regions where the V^E and Δβ_a are maximum negative in addition to some more regions and also for the participating pure liquid components. High-purity spectroscopic and HPLC grade chemicals of 2-Ethoxy ethanol and DMSO were obtained from Merck Co. Their purities were 99.5% or better and no further purification was done. The chemicals were stored over molecular sieves. The verification of the purity of the chemicals was realized by ascertaining the consistency of the values of density, viscosity and ultrasonic velocity at 298.15K which were reasonably in accordance with the values found in the literature. FTIR spectra were taken for the liquid mixtures in a FTIR spectrum photometer (Perkin Elmer Co. model 1605) by using the KBr pellet method.
The excess properties study shows that the maximum interaction occurs for the mole fraction value of 0.6 to 0.7 for 2-Ethoxy ethanol and 0.4 to 0.3 for DMSO which has been confirmed from the detailed spectroscopic study. The frequency shift and intensity variation shows the possibility of maximum interaction in this region when compared with other regions which confirms the conclusions obtained from the excess property studies.

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I. Johnson ¹, M. Kalidoss ¹, R. Srinivasamoorthy ¹

Affiliations
1 Dept. of Physics, St. Joseph's College, Tiruchirappalli-620002, IN

Abstract

Researches have previously shewn that the contribution of internal pressure and the temperature coefficient of volume to the sound velocity in the condensed phase is significant and that volume expansivity is the controlling factor for satisfactory description of the various parameters which describe the thermo-acoustic properties of polycrystalline solid, metal, alkali halide salt, polyatomic ionic liquid and organic liquid mixtures. Such a description employs only volume expansivity data. From the volume expansivity data the isothermal, isobaric and isochoric acoustical parameters, Moelwyn-Hughes parameter, fractional free volume, Huggin's parameter, Sharma's parameters and repulsive exponent in Mie's potential have been evaluated in the mixtures of Cyclohexanone+Heptane, Cyclohexanone+Hexane, Cyclohexanone+Octane and Cyclohexanone + 2, 2, 4-trimethyl pentane at 308.15 K for the entire range of mole fraction.

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