Environmental Science- ICAR JRF/SRF 2024

• Initiating Nuclear Fusion: Light nuclei (such as deuterium and tritium) carry positive electrical charges and repel each other via electrostatic Coulomb repulsion.
• Role of High Temperature: Initiating fusion requires extreme kinetic energies achieved only at temperatures exceeding $10^7$ to $10^8\text{ K}$, allowing nuclei to overcome the Coulomb electrostatic barrier and achieve strong nuclear force attraction.

Correct option: (3) High temperature

• Stratification of Facultative Ponds:
• Upper Aerobic Zone: Abundant sunlight and oxygen produced by photosynthetic algae supporting aerobic heterotrophic bacteria.
• Intermediate Facultative Zone: Inhabited by facultative bacteria that metabolize soluble organics oxidatively when dissolved oxygen is present or anaerobically via fermentation when oxygen is depleted.
• Bottom Anaerobic Zone: Devoid of oxygen, where anaerobic methanogens digest settled organic sludge.

Correct option: (3) Facultative bacteria

• Zero Liquid Discharge (ZLD): A comprehensive wastewater treatment engineering cycle where all effluent wastewater is treated, purified, and internal streams/rejects are recycled across all plant operations.
• Ultimate Goal: Eliminates the discharge of any liquid effluent into the surrounding environment, reducing effluent volume to dry solid salts while conserving fresh water intake.

Correct option: (2) The reject is recycled from every part of the treatment plant