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In the present study, Nano Silica (n-SiO2) as cementitious nanomaterial and Nano Zinc Oxide (n-ZnO) as non- cementitious nanomaterial in powder form are doped in the concrete mix to replace the cement by 0.5%, 0.75% and 1.0%. The specimens were casted with a constant Water Cement (W/C) ratio of 0.45 with an M25 mix design. From the experimental results, n-SiO2additives with 0.75% replacement and n-ZnO with 0.5% replacement increase the compressive strength by 16.54% and 6.32% and split tensile strength by 19% and 3.86% respectively as compared to the normal concrete. Hydration of Tricalcium Silicate (C3S) is a significant part of Bogue’s compound. Therefore, in the hydration process reactions of nanomaterials with C3S were investigated in this study. Additional cement gel formation due to n-SiO2helps to increase compressive strength as well as durability of concrete. The formation of the Zn(OH)2layer in the hydration process resists the water in cement. Due to doped nanoparticles, the size acid resistance properties of concrete are increased up to some extent but loses the concrete strength. With the help of optimized composition, the exact constituent of concrete can be easily identified for cementitious and non-cementitious nanomaterial. After that Ultrasonic Pulse Velocity (UPV) test was carried out for tap water and acidic media. The n-SiO2additives, concrete shows an excellent quality as compared to n-ZnO additives. As per UPV test results, n-SiO2additives are more suitable to use in the concrete. The outcome of this study will be helpful to the construction industry in understanding the effect of nano-composite in concrete.

Heterocycles are the main structural motif of DNA and RNA and play a crucial role in various chemical reactions of metabolisms. Therefore, heterocyclic compounds show good physiological and pharmacological properties. Coumarin and pyrazole scaffolds are present in many commercial drug molecules and natural products. This review overviews the progress made in the synthesis and functionalization of the coumarin- pyrazole hybrid heterocycle. It also includes discussion on the possible reactive sites of heterocycles, functionalization, and mechanistic pathways to incorporate pyrazole pharmacophore unit in synthesis. Several synthesis and biological studies reveal that the combination of the coumarin-pyrazole moiety is a prominent structural motif to find lead compounds in drug discovery.

Minimization of stress-induced mechanical rupture and delamination of conducting polymer (CP) films is desirable to prevent failure of devices based on these materials. Thus, precise in situmeasurement of voltage-induced stress within these films should provide insight into the cause of these failure mechanisms. The evolution of stress in films of polypyrrole (pPy), doped with indigo carmine (IC), was measured in different electrochemical environments using the multibeam optical stress sensor (MOSS) technique. The stress in these films gradually increases to a constant value during voltage cycling, revealing an initial break-in period for CP films. The nature of the ions involved in charge compensation of pPy[IC] during voltage cycling was determined from electrochemical quartz crystal microbalance (EQCM) data. The magnitude of the voltage-induced stress within pPy[IC] at neutral pH correlated with the radius of the hydrated mobile ion in the order Li+> Na+> K+. At acidic pH, the IC dopant in pPy[IC] undergoes reversible oxidation and reduction within the range of potentials investigated, providing a secondary contribution to the observed voltage-induced stress. We report on the novel stress response of these polymers due to the presence of pH-dependent redox-active dopants and how it can affect material performance.