In this study thermoreversible phase transitions of high (HMP) and low (LMP) melting point agarose gels were investigated by using the UV-vis and fluorescence spectroscopy techniques. Pyranine was added to the aqueous solution of agarose as a fluorescence-probe. Transmitted light (I (tr)) and fluorescence emission (I (fl)) intensities from the gel samples with different agarose concentrations were monitored during the heating (gel-sol) and cooling (sol-gel) processes. For the both techniques gel-sol ...

Effects of graphene nanoplatelet (GNP) addition on the electrical conductivity and optical absorbance of poly(methyl methacrylate)/graphene nanoplatelet (PMMA/GNP) composite films were studied. Optical absorbance and two point probe resistivity techniques were used to determine the variations of the optical and electrical properties of the composites respectively. Absorbance intensity A and surface resistivity R-s of the composite films were monitored as a function of GNP mass fraction (M) at room ...

Effects of multiwall carbon nanotube (MWCNT) addition on the electrical conductivities optical transparencies and fluorescence emissions of poly(vinyl acetate-co-butyl acrylate) (P(VAc-co-BuA))/MWCNT composite films were studied. Optical transmission fluorescence emission and two point probe resistivity techniques were used to determine the variations of the optical fluorescence and electrical properties of the composites respectively. Transmitted photon intensity (I-tr) fluorescence emission ...

A photon scattering technique for research on the sol-gel and gel-sol transitions in kappa-carrageenan-water systems with various carrageenan contents (CC) was utilized for characterizing the fractal dimensions during gelation and swelling. It was observed that the scattered photon intensity I-sc increased at all temperatures with an increase in the CC when I-sc was monitored against temperature. Additionally the sol-gel transition temperatures were found to be much lower than the gel-sol transition ...