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Q.62 If 𝑣⃗ = (2, 2, 2) is an eigenvector of the matrix ( 1 2 3 ; 1 2 3 ; 1 2 3 ) corresponding to the non-zero eigenvalue […]

Q61 Consider scale-up of fungal fermentation from model-type to 20,000 L prototype scale-up tank fermenter. The model-type and prototype have 20.0 L and 500 L impeller, respectively. The scale-up criterion […]

Q60 A fed batch process is running at quasi-steady state with respect to substrate and biomass concentration. Biomass concentration is 50 g L−1, glucose volume is 500 L, with constant […]

Q59 A fermenter is filled with medium at 1 L min−1. A leak develops at the bottom of the fermenter when the rate of medium leakages 200 L in t […]

Q58 E. coli is inoculated in a shake flask containing nutrient medium. The initial number of viable cells in the medium is 102. After few hours, the number of viable […]

Q57 The free energy change of ATP hydrolysis at 25°C is −32 kJ mol−1. The free energy change for the formation of α-glycerophosphate from glycerol and ATP is −8.2 kJ […]

Q.56 Ethanol is produced in a 10,000 L stirred bioreactor using an impeller of diameter 1 m. The density and viscosity of fermentation broth are 1000 kg m-3 and 1 […]

Q.55 Aspergillus niger is grown in a 10,000 L stirred batch bioreactor under aerated conditions to produce citric acid. At steady state oxygen transfer conditions, the specific oxygen uptake rate […]

Q.54 Fermentation medium is cooled from 121 °C to 30 °C in a double pipe heat exchanger. If cold water is flowing in the counter-current direction and is heated from […]

Q.53 Under complete cell washout condition in a chemostat with sterile feed, which of the following statements is/are correct? (A) Biomass concentration in the reactor is maximum (B) Substrate concentration […]