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The spectroscopic characterization of plasma generated in meteorite samples during Laser-Induced Breakdown Spectroscopy (LIBS) shows the emission spectrum of elements present and also allows one to rapidly identify the elemental composition without any sample preparation and with good accuracy compared to some other methods. In addition, LIBS has other advantages, such as multi-elemental response, micro–nano gram level of destructiveness and portability of the instrument. Since the presence of Rare Earth Elements (REEs) in meteorites is usually in trace levels or not at all, LIBS can be used as a potential alternative method for the meteorite fragment analysis which, in turn, gives valuable clues on its origin as well as the origin of the solar system and its impact on life on Earth, particularly on the presence of REEs. The elemental analysis results for a few of the selected samples, such as iron meteorites, lunar meteorites, eucrites and impact glass, are presented and discussed. The LIBS analysis was supplemented by Principal Component Analysis (PCA) with which it was possible to classify the samples into different classes according to their chief constituents, structure and origin.

Biodiesel synthesis from the pongamia oil seed and its characterization is elaborated in this paper. A double stage transesterification i.e. acid catalysed transesterification and base catalysed esterification are adopted to reduce the free fatty acids content and conversion of triglycerides into methyl esters. In this process, H2SO4, NaOH and methanol are used at the methanol/oil molar ratio of 7:1. By this process, 95% of pongamia biodiesel is obtained. The physiochemical properties like calorific value, Cetane number, density, kinematic viscosity, flash point, fire point etc. are analysed and it is found to be within the ASTM standards. GC-MS analysis indicated the existence of 14 prominent fatty acids with oleic acid as the major constituent. 13C and 1H NMR results supported the GC-MS data and it also confirmed the conversion efficiency of converting the vegetable oil into PBD as 87.23%. The shifting and appearance of major peaks in the FT-IR spectrum confirmed the formation of FAMEs from the triglycerides.

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