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TLS Online TPP Program

#Question id: 10143

In the carbon assimilation reaction of photosynthesis, the biosynthesis of 1 molecules of glucose from the 6 molecules of carbon dioxide requires;

#Section 2: General Biology
  1. six molecules of NADPH and three molecules of ATP and six molecules of water oxidised
  2. six molecules of NADPH and nine molecules of ATP and twelve molecules of water oxidised
  3. Tweleve molecules of NADPH and eighteen molecules of ATP and twelve molecules of water oxidised
  4. six molecules of NADPH and six molecules of ATP only
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TLS Online TPP Program

#Question id: 14217

#Section 5: Bioprocess Engineering and Process Biotechnology

In a microbial system how true yields are related to apparent growth yield? 
TLS Online TPP Program

#Question id: 14218

#Section 5: Bioprocess Engineering and Process Biotechnology

In CSTR system at steady rate  
TLS Online TPP Program

#Question id: 14219

#Section 5: Bioprocess Engineering and Process Biotechnology

A waste-water stream of F = 1 m3 /h with substrate at 2000 mg/l is treated in an upflow packed bed containing immobilized bacteria in form of biofilm on small ceramic particles. The effluent substrate level is desired to be 30 mg/l. The rate of substrate removal is given by the following equation
                   

By using the following information, determine the required height of the column (H). k = 0.5 h-1, X = 10 g/l, Ks = 200 mg/l, L = 0.2 mm, α = 100 m2 /m3 , A = 4 m2 , η = 0.8
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TLS Online TPP Program

#Question id: 14220

#Section 5: Bioprocess Engineering and Process Biotechnology

A value of kLa = 30 h^-1 has been determined for a fermenter at its maximum practical agitator rotational speed and with air being sparged at 0.5 l gas/l reactor volume-min. E. coli with a qO2 of 10 mmol O2/g-dry wt-h are to be cultured. The critical dissolved oxygen concentration is 0.2 mg/l. The solubility of oxygen from air in the fermentation broth is 7.3 mg/l at 30⁰C.
What maximum concentration of E. coli can be sustained in this fermenter under aerobic conditions?
TLS Online TPP Program

#Question id: 14221

#Section 5: Bioprocess Engineering and Process Biotechnology

E. coli have a maximum respiration rate, qO2max, of about 240-mg O2/g-dry wt-h. It is desired to achieve a cell mass of 20 g dry wt/l. The kLa is 120 h-1 in a 1000-l reactor (800 l working volume). A gas stream enriched in oxygen is used (i.e., 80% O2) which gives a value of C* = 28 mg/L. If oxygen becomes limiting, growth and respiration slow; for example,

                                     
   where CL is the dissolved oxygen concentration in the fermenter. What is CL when the cell mass is  at 20 g/l?
TLS Online TPP Program

#Question id: 14222

#Section 5: Bioprocess Engineering and Process Biotechnology

A stirred-tank reactor is to be scaled down from 10 m3 to 0.1 m3. The dimensions of the large tank are: Dt = 2 m; Di = 0.5 m; N = 100 rpm.Determine the dimensions of the small tank (Dt , Di , H) by using geometric similarity?
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