Nanoscience and Nanotechnology: UPSC Previous Year Questions (Science and Technology)

Explanation

Hydrogels are three-dimensional polymer networks that can absorb and retain large amounts of water while preserving their structure. With their biocompatibility, flexibility, and customizable properties, they are widely utilized across various applications.

Option 1 is correct: Hydrogels have a porous, water-attracting structure that allows them to expand and contract in response to stimuli. This makes them ideal for controlled drug delivery, ensuring precise and sustained release in liquid environments.

Option 2 is incorrect: Hydrogels are not commonly used in mobile air-conditioning systems. Air-conditioning relies on compressors, refrigerants, and heat exchangers, and though materials with moisture retention might play a minor auxiliary role (like evaporative cooling pads), hydrogels are not a standard component in these systems.

Option 3 is incorrect: Hydrogels do not serve as specific base materials or additives in conventional industrial lubricants. Industrial lubricants typically rely on oils, greases, and synthetic compounds designed for reducing friction and wear. Hydrogels are not chemically or mechanically suited for this purpose. Note: UPSC has given Option(a) as an official answer.

Explanation

Statement 1 is correct: Carbon fibre is a material consisting of very thin filaments of carbon atoms. Carbon fibers are fibers characterized by a carbon content of 90% or higher. The principal rationale behind the aerospace industry’s adoption of carbon fiber lies in the weight reduction it offers.

Statement 2 is incorrect: Carbon fibre is environmentally friendly and exhibits a longer life cycle. There are numerous technologies to recycle carbon fibres.

Explanation

Carbon nanotubes are cylindrical structures made of carbon atoms arranged in a hexagonal lattice. They possess exceptional strength, high electrical conductivity, and unique mechanical properties, making them promising materials for applications in electronics, materials science, and nanotechnology.

Statement 1 is correct: Carbon nanotubes (CNTs) have been widely researched for their role in drug delivery systems. Their unique hollow structure allows them to transport therapeutic molecules directly to targeted cells, improving treatment precision and effectiveness. Functionalization of CNTs enhances biocompatibility and minimizes toxicity.

Statement 2 is incorrect: Carbon nanotubes have applications in tissue engineering, including constructing artificial blood vessels. Their mechanical strength and ability to support cell growth make them useful for creating scaffolds that mimic natural capillaries, promoting tissue repair. However, UPSC in its official answer key has not given recognition to this development and marked statement 2 as incorrect.

Statement 3 is correct: Due to their exceptional electrical conductivity, carbon nanotubes are integral to the development of highly sensitive biochemical sensors. These sensors can detect specific biological molecules, contributing to advancements in diagnostics and monitoring technologies.

Statement 4 is correct: Multiple types of microbes, including bacteria and fungi, have the ability to degrade carbon nanotubes (CNTs). Thus carbon nanotubes are very much biodegradable in nature.

Explanation

: Nanotechnology is a field of science and engineering that deals with the manipulation of matter on an atomic and molecular scale, typically between 1 to 100 nanometers. It involves the design, synthesis, characterization, and application of materials, devices, and systems at this incredibly small scale. This emerging field has the potential to revolutionize various sectors, including medicine, electronics, materials science, and energy, by creating new materials with unique properties and developing innovative technologies with unprecedented capabilities.

Statement 1 is correct: Targeted drug distribution by nanoscale drug carriers is one of the fundamental tenets of nanomedicine. Numerous nanoscale drug delivery technologies, such as liposomes, dendrimers, quantum dots, nanotubes, polymeric biodegradable nanoparticles, and nanocapsules, have been studied.

Statement 2 is correct: Nanotechnology plays a significant role in gene therapy by creating nanocarriers that can deliver genetic material, such as DNA or RNA, to specific cells. These nanocarriers protect genetic material from degradation and improve its delivery into target cells, offering potential treatments for genetic disorders.

Explanation

Option (c) is correct: DSL (Digital Subscriber Line) is a wired broadband technology that uses telephone lines to transmit digital data. It is used for high-speed internet connections, but it is not a wireless technology. It does NOT belong to the GSM (Global System for Mobile Communication). DSL is a wired broadband technology that provides internet access over telephone lines and is unrelated to mobile networks. Options (a), (b) and (d) are incorrect:

EDGE (Enhanced Data Rates for GSM Evolution) belongs to the GSM family. It is an enhancement of GPRS (General Packet Radio Service) and is considered part of 2.5G and 2.75G networks within the GSM framework. LTE (Long-Term Evolution) belongs to the GSM family. LTE is a 4G technology that evolved from GSM and UMTS (Universal Mobile Telecommunications System). It provides high-speed wireless communication but is not strictly GSM-based; however, it is considered part of the evolutionary path of GSM networks.