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This study is aimed to analyze the use of electronic resources and services in the Library System of the Affiliated institutions of University of Madras. Under graduate students, Post graduate students, Research scholars, faculties were selected for this study. Questionnaire method was adopted to collect the data. Out of 1030 questionnaires 935 (90.77%) were received from respondents. There are about 161 Educational Institution affiliated to University of Madras, of which 15 are Government Colleges, 2 University Constituent Colleges, 24 Aided Colleges, 68 Self Finance Colleges and 52 Research Institutes. Out of these 161 Educational Institutions 136 offer Science courses. Apart from this the university itself has 31 departments catering to Science subjects spread over 3 different campuses. Altogether 167 Institutions affiliated to University of Madras are offering courses in science subjects. Out of these, 45 (8 Govt. Colleges, 12 Aided Colleges, and 25 Self Finance Colleges), Institutions Affiliated to University of Madras have been selected for the study.

Gd2O3 nanoparticles synthesized by solution combustion method were used to prepare PVA-Gd2O3 nanocomposite films of varying concentrations (2 wt%–6 wt% of filler) by solution casting method. Being a rare earth oxide, gadolinium oxide was expected to exhibit good photoluminescence and the nanocomposite was expected to be flexible as well. The Gd2O3 nanoparticles prepared were found to be in cubic phase with an average size of 19 nm. Raman spectra showed the incorporation of Gd2O3 into the polymer matrix. Scanning electron microscope images revealed that the particles were porous in nature, agglomerated and distributed evenly on the surface of the film in the form of clusters. The UV–Visible absorption spectra gave direct optical energy band gap value in the range 5.78–4.86 eV. Both band gap as well as the Urbach energy are seen to decrease with increasing concentration of the dopant. Four prominent photoluminescence peaks were observed in all the three composite films in the UV region (318 nm), deep blue region (396 nm), blue region (477 nm) and green region (553 nm). The color purity of the films using CIE coordinates was found to be the highest, 82.81%, in the 2 wt% film making this film a promising material for blue OLED’s and blue flexible screens.

This study is aimed to analyze the use of electronic resources and services in science subjects by the Madras University Library System. Post graduate students, Research scholars, faculties were selected for this study. Questionnaire method was adopted to collect the data. Out of 745 questionnaires 724 (97%) were received from respondents. There are about 161 Educational Institution affiliated to University of Madras of which 15 are Government Colleges, 2 University Constituent Colleges, 24 Aided Colleges, 68 Self Finance Colleges and 52 Research Institutes. Out of these 161 Educational Institutions 136 offer Science courses. Apart from this the university itself has 31 departments catering to Science subjects spread over 3 different campuses. Altogether 167 Institutions, affiliated to University of Madras, are offering courses in science subjects. Out of these, 31 University departments have been selected for the study.

Nanocomposite films of CeO2 doped polyvinyl alcohol (PVA) of varying concentrations were prepared by a solution casting technique using nanoparticles synthesized by a solution combustion method. Energy Dispersive X-ray (EDX) confirmed the presence of constituent elements in the composite films. The characterization by X-ray Diffraction (XRD) gave the structure of the CeO2 nanoparticles as cubic fluorite and the size of the nanoparticles in the composites as 6.5–44 nm. Scanning Electron Microscopy (SEM) and High Resolution Transmission Electron Microscopy (HRTEM) show homogenous dispersion of nanoparticles with increasing size and some agglomeration for concentrations upto 12.5 wt% while the 25 wt% film is radically different showing a tape-like structure in SEM images and a string of beads-like formation of nanoparticles in the HRTEM images. Raman spectra exhibit shifts as well as new bands in the composites confirming structural change and formation of a new material. The UV-Visible spectrum of the composites exhibit a red shift in the optical band gap with respect to pure PVA and both red and blue shift with respect to nano CeO2 depending on the concentration of the filler. Good absorption in the UV (2.5 wt% and 25 wt%) and visible range (12.5 wt% and 25 wt%) suggest possible use in filters and solar cells. Photoluminescence studies reveal three emission peaks corresponding to the UV region and blue–green regions of the visible range. The maximum PL intensity, nearly equal to that of nano CeO2, was observed for 2.5 wt% films suggesting that this concentration is most suitable for optoelectronic applications.

Dielectric and conductivity behaviors of nano ZnO doped polyvinyl alcohol (PVA) composites for various concentrations of dopant were investigated using impedance spectroscopy for a wide range of temperatures (303 K–423 K) and frequencies (5 Hz–30 MHZ). The dielectric properties of host polymer matrix have been improved by the addition of nano ZnO and are found to be highly temperature dependent. Anomalous dielectric behavior was observed in the frequency range of 2.5 MHz–5 MHz. Increase in dielectric permittivity and dielectric loss was observed with respect to temperature. The Cole-Cole plot could be modeled by low resistance regions in a high resistance matrix and the lowest resistance was observed for the 10 mol. % films. The imaginary part of the electric modulus showed asymmetric peaks with the relaxation following Debye nature below and non-Debye nature above the peaks. The ac conductivity is found to obey Jonscher's power law, whereas the variation of dc conductivity with temperature was found to f...