Semitransparent composite films were prepared made from TiO 2 nanotubes in chitosan (CS) matrix. Hydrothermally synthesized titanium nanotubes (TiNTs) were dispersed in chitosan matrix in order to produce filmforming solutions at 0.05 and 0.10% w/v. Structural, topological, optical and thermal properties of these films were evaluated. The antimicrobial activity of films against Salmonella enterica serovar Typhimurium, Escherichia coli (Gramnegatives) and Staphylococcus aureus (Gram-positive) was also investigated. Fourier transform infrared (FTIR) spectra showed effective site-selective interactions between chitosan and TiNTs. TiNTs prevented the degradation of films, avoiding the oxidization of the glucosamine ring. Characterizing techniques such as, Scanning electron microscopyenergy dispersive spectroscopy (SEM-EDS) line profile and atomic force microscopy (AFM) were used to examine the TiNTs dispersion within the film. The morphological analysis indicated that the TiNTs were well dispersed and became clustered proportionally to the weight percentage of TiNTs used in the composites. The UV-Vis spectra showed that TiNTs increased the film absorption in the UV region and the light barrier properties of films remained stable over the storage period. Photoacoustic spectroscopy (PAS) was used to study these films, nondestructively for their thermal effusivity (e). The films were effective in reducing the microbial concentration in the liquid culture for all bacteria tested. The effectiveness was found to dependent on the bacterial strain and TiNTs content.

Phenanthroline-based hexadentate ligands L(1) and L(2) bearing two achiral semicarbazone or two chiral imine moieties as well as the respective mononuclear complexes incorporating various lanthanide ions, such as La(III), Eu(III), Tb(III), Lu(III), and Y(III) metal ions, were synthesized, and the crystal structures of [ML(1)Cl(3)] (M=La(III), Eu(III), Tb(III), Lu(III), or Y(III)) complexes were determined. Solvent or water molecules act as coligands for the rare-earth metals in addition to halide anions. The big Ln(III) ion exhibits a coordination number (CN) of 10, whereas the corresponding Eu(III), Tb(III), Lu(III), and Y(III) centers with smaller ionic radii show CN=9. Complexes of L(2), namely [ML(2)Cl(3)] (M=Eu(III), Tb(III), Lu(III), or Y(III)) ions could also be prepared. Only the complex of Eu(III) showed red luminescence, whereas all the others were nonluminescent. The emission properties of the Eu derivative can be applied as a photophysical signal for sensing various anions. The addition of phosphate anions leads to a unique change in the luminescence behavior. As a case study, the quenching behavior of adenosine-5'-triphosphate (ATP) was investigated at physiological pH value in an aqueous solvent. A specificity of the sensor for ATP relative to adenosine-5'-diphosphate (ADP) and adenosine-5'-monophosphate (AMP) was found. (31)P NMR spectroscopic studies revealed the formation of a [EuL(2)(ATP)] coordination species.

Silver nanowires (Ag-NWs) were obtained using microwave-assisted hydrothermal method (MAH). The main advantage of the method is its high NWs production which is greater than 90%. It is also easy, fast, and highly reproducible process. One of the drawbacks presented so far in the synthesis of nanostructures by polyol path is the high temperature used in the process, which is superior than the boiling point of solvent (ethylene glycol), and also its excessive reaction time. Here, Ag-NWs with diameters of 70 to 110 nm were synthesized in 5 min in large quantities. Results showed that dimensions and shape of nanowires were very susceptible to changes with reaction parameters. The reactor power and reactor fill capacity were important for the synthesis. It was found that the reaction time needs to be decreased because of the NWs which start to deform and break up due to significant increase in the pressure's system. Energy-dispersive X-ray spectroscopy and electron diffraction analysis (SAED) did not show corresponding phases of AgO. Some aspects about synthesis parameters which are related to the percent yield and size of nanowires are also discussed.

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Measurements on thermal diffusivity (α) and electrical switching studies have been undertaken on bulk, melt-quenched Ge22Te78−xIx (3≤x≤10) chalcohalide glasses. The thermal diffusivity values of Ge22Te78−xIx glasses lie in the range 0.09–0.02 cm2 s−1, and are found to decrease with increase in iodine content. The variation of α with composition has been understood on the basis of fragmentation of the Ge–Te network with the addition of iodine. The composition x = 5 (), at which a cusp is seen in the composition dependence of thermal diffusivity, has been identified to be the inverse rigidity percolation threshold of the Ge22Te78−xIx system at which the network connectivity is completely lost. Further, Ge22Te78−xIx glasses are found to exhibit memory-type electrical switching. At lower iodine concentrations, a decrease is seen in switching voltages with an increase in iodine content, in comparison with the switching voltage of the Ge22Te78 base glass. The observed initial decrease in the switching voltages with the addition of iodine is due to the decrease in network connectivity. An increase is seen in switching voltages of Ge22Te78−xIx glasses at higher iodine contents, which suggests the domination of the metallicity factor of the additive atoms on the switching voltages at higher iodine proportions. It is also interesting to note that the composition dependence of the threshold voltages shows a slope change at x = 5, the inverse rigidity percolation threshold of the Ge22Te78−xIx system.