Council of Scientific and Industrial Research (CSIR)

* Carbon fibres are highly valued for their unique properties like strength, lightness, and stiffness. They are widely used in the manufacturing of various components in automobiles and aircraft to reduce weight and improve performance.  * Carbon Fiber Recycling: While traditional carbon fibre recycling methods were limited, advancements are being made in this field. Here are some possibilities  1. Mechanical recycling - This process breaks down carbon fibres into smaller pieces for use in applications where their original form is not necessary.  2. Chemical recycling -This method dissolves the resin holding the fibres together, potentially allowing the extraction of reusable carbon fibres.  3. Thermal recycling - High temperatures are used to convert the resin into usable materials while recovering the carbon fibres.  * These recycling technologies are still evolving, but they offer a more sustainable approach to using carbon fibres. Hence, statement 2 is incorrect.

* Membrane Bioreactors are often discussed in the context of: D. Wastewater treatment technologies. * Membrane Bioreactors (MBRs) combine a membrane process like microfiltration or ultrafiltration with a biological wastewater treatment process. * They are used to improve the quality of treated wastewater and are known for their efficiency in removing contaminants.

Activated carbon is widely used to clean pollutants because of its unique properties and sustainable production methods. ✅ Statement I: Correct. Activated carbon effectively removes pollutants from industrial effluents due to its high adsorption capacity. It’s commonly used in water treatment and pollution control. ✅Statement II: Correct. This is because activated carbon has an extremely large surface area, created by its porous structure, allowing it to trap heavy metals and other contaminants efficiently. ✅ Statement III: Correct. Moreover, activated carbon can be produced easily and cost-effectively from carbon-rich wastes like coconut shells, rice husks, and other agricultural residues, making it an eco-friendly option. Thus, both Statement II and Statement III are correct, and together they explain why Statement I is true.

Statement 1 is correct: Permaculture farming indeed discourages monocultural practices, promoting biodiversity and the efficient use of available resources. On the other hand, conventional chemical farming often involves monoculture practices. Statement 2 is correct: Conventional chemical farming can lead to an increase in soil salinity due to the heavy use of synthetic fertilizers and pesticides, while permaculture farming promotes soil health and does not contribute to soil salinity. Statement 3 is incorrect: The statement about conventional chemical farming being easily possible in semi-arid regions but permaculture farming not being so easily possible in such regions is not necessarily true. Permaculture farming can be adapted to various climates and environments, including semi-arid regions, by using appropriate design principles and techniques. Statement 4 is correct: The practice of mulching, which involves covering the soil with organic material to conserve moisture, suppress weeds, and improve soil health, is an important aspect of permaculture farming, but it is not necessarily a key practice in conventional chemical farming.

Statement 1 is correct: Nanoparticles from industry can pollute air, water, and soil due to their small size and resistance to breakdown. This buildup can harm plants, and animals, and even contaminate drinking water. Statement 2 is correct: Nanoparticles can be inadvertently ingested by plants or animals, entering the food chain. As they move up the food chain, they can bioaccumulate in organisms, potentially causing harm at higher trophic levels. Statement 3 is correct: Some nanoparticles can trigger the production of free radicals in cells. Free radicals are highly reactive molecules that can damage cells and contribute to various health problems, including inflammation and cancer.