The present work demonstrates the application of a composite of the zeolite imidazole framework (ZIF-67) and reduced graphene oxide (rGO), synthesized via a simple hydrothermal route for the sensitive sensing of ammonia. The successful synthesis of ZIF-67 and rGO composite was confirmed with structural and spectroscopic characterizations. A porous structure and a high surface area (1080 m 2 g –1 ) of the composite indicate its suitability as a gas sensing material. The composite material was coated as a thin film onto interdigitated gold electrodes. The sensor displays a change in its chemoresistive property (i.e., resistance) in the presence of ammonia (NH 3 ) gas. A sensor response of 1.22 ± 0.02 [standard deviation (sd)] is measured for 20 ppm of NH 3 , while it shows a value of 4.77 ± 0.15 (sd) for 50 ppm of NH 3 . The fabricated sensor is reproducible and offers a stable response, while also providing tolerance against humidity and some other volatile compounds. The average response and recovery times of the sensor, for 50 ppm NH 3 concentration, are found to be 46.5 ± 2.12 (sd) and 66.5 ± 2.12 (sd) s, respectively. The limit of detection of the sensor was found to be 74 ppb.

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Depletion of oil reserves, increasing prices of petroleum products, and environmental concerns related to air pollution are the main driving forces for utilizing renewable energy resources to replace fossil fuels. Vegetable oils can be used to produce biodiesel. Biodiesel is obtained by transesterification of vegetable oil with alcohol using homogeneous or heterogeneous catalysts. In the industry, biodiesel is produced by heterogeneous catalysts due to high activity and selectivity, better reusability, reduction in processing steps, and wastes. The catalytic activity of catalysts depends on the strength and type of intrinsic basic or/and acid properties. Biodiesel production using heterogenous catalysts depends on the various reaction parameters such as reaction time, temperature, molar ratio of alcohol to oil, catalyst amount, and stirring speed. In this paper, the catalytic transesterification of various feedstocks such as edible oil, non‐edible oil, and waste using heterogeneous catalysts has been reviewed and optimization parameters for maximum biodiesel production have been summarized.

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We have synthesized six new congeners of acetamidobenzoxazolone for Translocator Protein [18 kDa, TSPO] imaging. The best in vitro binding affinity (10.8 ± 1.2 nm) for TSPO was found for N-methyl-2-(5-(naphthalen-1-yl)-2-oxobenzo[d]oxazol-3(2H)-yl)-N-phenylacetamide, (NBMP). NBMP was synthesised by Suzuki coupling reaction between 2-(5-bromo-2-oxo-1,3-benzoxazol-3(2H)-yl)-N-phenylacetamide and napthalene-1-boronic acid. Computational docking and simulation studies showed not much impact of intersubject variability on binding which is one of the major drawbacks of several TSPO ligands. These findings suggested that NBMP may become a promising marker for visualization of neuroinflammation via TSPO targeting.