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A set of nanocomposite films of poly-vinyl alcohol (PVA) and 0.1–0.4 wt% CdSe nanoparticles (NPs) were developed by spin coating and their surface resistance (R) was measured as a function of light illumination intensity (IL) and applied magnetic field (H). The ferromagnetic CdSe NPs were synthesized by a facile chemical method which ensured in situ surface stabilization with a skinny layer of graphitic carbon. The CdSe NPs were uniformly dispersed in an aqueous solution of 2.0 wt% PVA and spin-coated on fluorine-doped tin oxide coated glass substrates. The photoresponse of the nanocomposite films at low H exhibits their efficacy for pertinent applications in optoelectronics. [ABSTRACT FROM AUTHOR]

Structural, optical, and electrical properties of granular thin films of CdSe deposited on HfO 2 dielectric layer are reported. The thin films were deposited on fluorine-doped tin oxide (FTO) coated glass substrates by e -beam evaporation technique. Structural analysis revealed the amorphous nature of the HfO 2 , whereas wurtzite type hexagonal crystal structure was observed in the CdSe thin films. Microstructural analysis showed the granular nature of both the deposited layers. The optical and electrical properties of the thin films were studied in detail. The dielectric properties of the deposited layers were studied in correlation with their microstructure. The appearance of negative permittivity (NP) in the films indicates towards metamaterial type characteristics which has various potential applications viz. high permittivity capacitors, microwave filters, coil free resonators, and thin film transistors (TFTs). [Display omitted] • Granular CdSe thin films were deposited on HfO 2 dielectric by e -beam evaporation. • Optical and electrical properties of the CdSe thin films were studied extensively. • The thin films show metamaterial type characteristics with negative permittivity. • This type of CdSe thin films has numerous potential applications. [ABSTRACT FROM AUTHOR]

Plain jointed concrete pavements laid in Mumbai City (India) during the early 1990s were structurally evaluated using a falling weight deflectometer (FWD) and testing of concrete cores extracted from the pavement slabs. The ultrasonic pulse velocity (UPV) of the concrete in the cores was determined first and then the cores were crushed under compression. The pavement deflections were found to be within the limits as suggested in the Indian codes and the international literature. The joint conditions were also found to be satisfactory. The design strength of the concrete was back-calculated from the compressive strength of the cores and was found to conform to the design specifications. However, the construction quality was found wanting as the thickness of pavement slabs at a few locations was lower than that specified and it has resulted in cracking of the slabs. The dynamic modulus of elasticity of concrete as determined by the FWD was found to correspond well with that computed from the UPV of cores and from the compressive strength of concrete. A method is suggested to estimate the structural parameters of uncracked pavement slabs from the dynamic modulus of elasticity obtained through the indirect method of UPV testing which is less expensive compared to evaluation by the FWD. [ABSTRACT FROM AUTHOR]

Presents a correction to the article "Structural Evaluation of Cement Concrete Roads in Mumbai City" that was published in the May 2006 issue of the journal.