Nitropyridoindoles—Formation,characterization and mutagenicity

Nitration of pyridoindoles (β‐carbolines) was carried out using different nitration methods and structural assignments of these nitro compounds were made using different spectroscopic techniques. The mutagenic activity of these nitro derivatives was studied using Salmonella typhimurium strains TA 98 NR and TA 100 NR in the absence as well as in the presence of S‐9 mix. Only trinitro derivatives were found to be highly mutagenic to strain TA 98 NR.     

Synthesis of artificial aggregates and their impact on performance of concrete: a review

Infrastructure development and urbanization have created a demand for the prime construction material—"Concrete." The manufacture of concrete has pressurized the aggregate supply chain for over-exploitation of natural resources leading to eco-detrimental impacts besides environmental regulations. The auxiliary sectors of the construction industry are creating a vast quantum of by-products and waste, causing environmental degradation, which concerns governing bodies. Developing aggregates artificially using these by-products and waste materials would be an eco-friendly and economical solution. This article provides an overview of the ingredients, production methods, and factors influencing the characteristics of such sustainable building materials, which can substitute conventional aggregates in the near future.