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This paper presents a comparative study of physical properties of a sample of 89 blue early-type galaxies (ETGs) from the local universe by fitting SEDs to their multi-wavelength photometric and spectroscopic data. The detailed template-based SED fitting analysis using the MAGPHY S and SED3FIT codes on the interstellar dust extinction corrected UV-to-far-IR spectro-photometric data enabled us to trace the evolutionary sequence of the blue ETGs on the color-magnitude diagram. This study evidenced a decreasing trend of the SFR, sSFR, dust mass, and dust mass fraction over the sequence from the SF - to - the Seyferts - to - the LINERs. The UV-optical colors also enabled us to estimate the look-back time of the last starburst phase in SF, Seyfert, and LINER galaxies, probably pointing towards the evolutionary sequence of the blue ETGs. Despite the blue colors and strong emission lines in the optical regime of the electromagnetic spectrum, the blue ETGs in the present sample occupy a position off the main sequence, commonly known as the green valley, on the CMD plot and hence indicate the transitional state of their non-secular evolution. A marginal positive correlation was noticed between SFR per unit dust mass and the temperature of the cool ISM. The declining trend of the cold dust temperature Tc over the sequence from the SF-to-Seyfert-to-LINER implies that the AGNs in the systems are not enough powerful to affect the cold component of the ISM.

Polyvinyl chloride (PVC) is one of the most commonly used thermoplastic materials in cables and wires for electrical insulation. PVC has very good-to-excellent electrical and mechanical properties which make it suitable for use as an electrical insulating material in many domestic and industrial electrical insulation applications. Mica-filled PVC composites may become the cost-effective substitutes for other types of cable and wire compositions with their improved properties. In this study, water ground mica samples of different particle sizes, surface areas, and concentrations were used for fabrication of PVC composites with and without its surface treatment. Haake Rheochord 9000 compounder using roller-type blades was used for the fabrication of different PVC test composites. Melt-compounded composite was compression molded for making sheets. Mechanical and electrical properties were determined using these test sheets. Mechanical properties such as Young’s modulus, stiffness, and shore hardness increased with increase in mica concentration, whereas tensile strength and elongation at break values are found to decrease with increase in mica concentration. Dielectric properties also increase with mica loading. Morphological studies revealed that there was good adhesion and dispersion of the mica in the PVC composite. It was revealed that mechanical and electrical properties were marginally improved with the use of silane-treated mica. [ABSTRACT FROM AUTHOR]

Abstract: Creep behavior of metal matrix composites is similar to dispersion strengthen alloys and characterized by the presence of a threshold stress below which the creep rate is negligible. This threshold stress is attributed, at least in dispersion-strengthened alloys, to dislocation particle interactions in which the detachment of the dislocations from the particle is the rate-limiting step. Creep experiments were performed on an Al–5Y2O3–10SiC composite in the temperature range of 473 and 573K and the nature of the dislocation–particle interaction was determined by performing in situ straining experiments at elevated temperature in a transmission electron microscope. The threshold stress and the detachment stress are temperature dependent and the detachment stress is less than the threshold stress emphasizing the contribution of load transfer from the matrix to the reinforcement phase. [Copyright &y& Elsevier]

Abstract: Creep tests were performed on a fine-grained Al–6Mg–1Sc–1Zr–10vol.% SiC particulate composite in the temperature range of 423–533K. The composite exhibited a high value of apparent stress exponent and apparent activation energy for creep at low temperatures. The flow behavior of this composite was characterized by the presence of a threshold stress. Incorporation of threshold stress into analysis reduces the high values of apparent stress exponent and activation energy to those anticipated from the creep of solid solution alloys. The result showed increased creep resistance in the composite compared to the unreinforced alloy. [Copyright &y& Elsevier]