Publications by authors named "S M Hanagodimath"

At room temperature, the absorption and fluorescence properties of coumarin 6-Methoxy-4-(4-nitro-phenoxy methyl)-chromen-2-one (6MNPM) are investigated in pure organic solvents and a combination of acetonitrile (ACN) and tetrahydrofuran (THF). The pure solvents' influence on spectral characteristics is examined by applying theories such as Kamlet and Catalan's multiple linear regression techniques, Reichardt's microscopic solvent polarity parameter, and the Lippert-Mataga polarity function. The significant role of solute-solvent interactions in pure solvents, particularly dielectric interaction and hydrogen bonding.

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The effects of solvent on the absorption and emission spectra and dipole moments of the 5ABBM have been extensively studied in a series of solvents. The dipole moments in the excited state are observed to be greater than those in the ground-state in all the solvents studied for the chosen molecule. The dipole moment increase in the excited singlet state ranges from 2.

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The effect of solvents of varying polarity and hydrogen bonding ability, solvent mixture and silver nanoparticles on the photophysical properties of a ketocyanine dye, 2,5-di[(E)-1-(4-diethylaminophenyl) methylidine]-1-cyclopentanone (2,5-DEAPMC), is investigated at room temperature. Solvent effect is analyzed using Lippert-Mataga bulk polarity function, Reichardt's microscopic solvent polarity parameter, and Kamlet's and Catalan's multiple linear regression approaches. The spectral properties better follow Reichardt's microscopic solvent polarity parameter than the Lippert-Mataga bulk polarity function.

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Energy absorption geometric progression (GP) fitting parameters and the corresponding buildup factors have been computed for human organs and tissues, such as adipose tissue, blood (whole), cortical bone, brain (grey/white matter), breast tissue, eye lens, lung tissue, skeletal muscle, ovary, testis, soft tissue, and soft tissue (4-component), for the photon energy range 0.015-15 MeV and for penetration depths up to 40 mfp (mean free path). The chemical composition of human organs and tissues is seen to influence the energy absorption buildup factors.

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The effect of temperature on the fluorescence intensity of 4-(5-methyl-3-furan-2-yl-benzofuran-2-yl)-7-methyl-chromen-2-one (MFBMC) in different solvents, has been studied in the temperature range 293-333K. A mechanism of fluorescence quenching with increase in temperature is discussed in terms of the relative location of lowest (1)(pipi*) and (3)(npi*) states, and the energy difference between them. The non-radiative deactivation of excited state in the absence of quencher is temperature-dependent; its activation energy has been found to be 9.

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