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Here, we present comprehensive electron probe micro analysis, laser Raman spectroscopic and X-ray diffraction (XRD) studies on the Mahadevpur H4/5 chondrite. The calculated full width at half maximum (FWHM) value of ~14-17 cm-1 for the Raman peaks in the Mahadevpur meteorite is in accordance with the shock stage of S4 with medium shock pressure regime of 30-35 GPa. The nanodiamonds were characterized with the observation of Raman peaks at 1333-1358 cm-1 and 1600 cm-1. The FWHM value of the Raman peaks reflects shock metamorphism in the meteorite. The XRD technique provides further independent validation of the nanodiamonds. [ABSTRACT FROM AUTHOR]

We demonstrate herein the catalytic performance of unsupported Ni(OH)2 nanoparticles towards the dehydrogenation of primary alcohols to corresponding acids under aerobic conditions in refluxing toluene. An assortment of aromatic and aliphatic carboxylic acids/acids salts was prepared from corresponding alcohols in moderate to excellent yields. Interestingly, the protocol can also be employed to synthesize carboxylic acids on a gram scale, demonstrating the practical utility of the method. Mechanistic studies suggest that the reaction proceeds through an acceptorless dehydrogenation strategy and follow both Cannizzaro and catalytic dehydrogenative path. Broad substrate scope, operational simplicity, low cost, and reusability are the most interesting features of the current heterogeneous catalytic protocol described herein. [ABSTRACT FROM AUTHOR]

ABSTRACT Plant oil based alkyd resin was prepared from jatropha oil and blended with epoxy resin. Subsequently, alkyd/epoxy/NiO nanocomposites with different wt % of NiO nanoparticles have been prepared by mechanical mixing of the designed components. The structure, morphology, and performance characteristics of the nanocomposites were studied by UV-visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and universal testing machine (UTM). The alkyd/epoxy/NiO nanocomposites showed the gradual increase in thermal stability with increasing NiO content. With 3 wt % NiO content the tensile strength of the nanocomposite increased by 19 MPa (more than twofold) when compared with the pristine polymer. Limiting oxygen index (LOI) value of the nanocomposites indicate that the incorporation of NiO nanoparticles even in 1 wt % can greatly improves the flame retardant property of the nanocomposites. This study confirms the strong influence of NiO nanoparticles on the thermal, mechanical, and flame retardant properties of the alkyd/epoxy/NiO nanocomposites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41490. [ABSTRACT FROM AUTHOR]

We present here optical properties and crystallinity index of quartz (SiO2) in natural rocks samples from the Mikir and Khasi hills, Assam, India. Infrared spectroscopy has been used to study the structure of quartz in rock samples and estimate the mining quality of quartz mineral, which is substantiated by calculating the crystallinity index. Systematic investigations of structure have been carried out in between 10 μm (1000 cm-1) and 20 μm (500 cm-1) bands of silicates. Investigation is based on the assignment of infrared bands to certain structural groups of SiO4 tetrahedra. The crystallinity of samples has been ascertained by comparing the ratio of intensity of the characteristic peak at 778 and 695 cm-1 with the corresponding ratio for a standard sample. The crystallinity parameter is calculated by using a standard procedure which can be used to estimate the distribution of quartz in various rocks for mining purpose. The infrared spectroscopic investigation is found to be an ideal tool for structure elucidation and for estimating quartz crystallinity of the natural samples. [ABSTRACT FROM AUTHOR]