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The high specific stiffness materials are used to design the space payload components. These components should sustain the extreme environmental condition throughout their life cycle without failure. The prerequisites of future space missions need lightweight materials which must be mechanically strong and high thermal and electrically conductive. The Carbon Nanotubes (CNTs) are efficient filler material in composite or metal matrix to enhance greater electrical and thermal conductivity. The quality of the CNT nano composite relies upon several parameters like the types of CNTs, its purity, aspect ratio, amount of loading, alignment, and interfacial adhesion between the nanotube and polymer. The performance of the CNT-CFRP composite depends on the successful execution of the processing technique. This review paper intends to highlight the enhancement of the mechanical, thermal, electrical properties of the composite, and the challenges to achieving it. This review paper helps to optimise the process parameters to fabricate Space Payload Components, required to replace existing high-density Space Qualified Materials. This review paper should help optimize the process parameters to fabricate Space Payload Components, which can be excellent alternatives to the existing high-density Space Qualified Materials without making any compromise on the performance index. [ABSTRACT FROM AUTHOR]

The present study reports a simple and eco-friendly synthesis of copper oxide nanoparticles (CuO NPs) using green synthetic route. The synthesis of copper oxide nanoparticles is explored using reducing as well as stabilizing properties of Elettaria cardamomum (elaichi). The copper oxide nanoparticles are duly characterized using ultraviolet–visible (UV–Vis) spectrometer, dynamic light scattering (DLS) and zeta-potential methods. The UV–Vis spectra confirm the formation of dark brown coloured CuO nanoparticles with a characteristic peak at the λmax value of 220 nm. Due to capping of stabilizing agents around both copper oxide nanoparticles, the hydrodynamic particle size as revealed by DLS experiments is found to be of 175 nm. The stability and overall charge on the nanoparticles are found by its zeta potential, which is found to be of −16.2 mV. Antibacterial activities of copper oxide nanoparticles are tested against both Gram-positive and Gramnegative bacteria. Thus, the present method proves to be the most appropriate for large-scale green synthesis of copper oxide nanoparticles. [ABSTRACT FROM AUTHOR]

Recent advances in functionalized organic Spiro heterocyclic compounds composed of nitrogen bonded five- and six-membered rings have been made, establishing them as a synthetic target in organic-based biomedical applications. In this work, we report a synthesis of spirocyclic compounds under a one-pot reaction using 1,3-dipolar cycloaddition in a regio and diastereoselective manner. The higher atomic economy with higher yield (95%) and regio and stereoselectivity were achieved by a multi-component reaction of L-proline (1), Indenoquinoxaline (2), and the dipolarophile of malononitrile (3) solvents followed by reflux conditions. The reaction intermediate comprised azomethineylides derived from reactive primary amines, and the spiro derivatives were synthesized up to a ≈ 95% yield. The structural and characteristic chemical components of the as-prepared Spiro compounds were characterized by 1H-NMR, FTIR, and Mass spectroscopy. The functionalized spiro-pyrrolizidines were found to be effective for biological uses by considering their in vitro screening and antimicrobial impacts. Spiro constituents were found to be much more effective for Gram-positive bacteria due to the stronger lipophilic character of the molecules, and they resulted feasible membrane permeation in a biological system. Based on the planarity geometry of the Spiro pyrrolizidines, meta-substitution possesses steric hindrance and hence shows less effectiveness compared to para-substitution on the same nucleus, which shows a marginal steric effect. The biological studies showed that the derived spiro heterocyclic systems have an inhibitory effect of 50%. [ABSTRACT FROM AUTHOR]