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TLS Online TPP Program

#Question id: 125

Regions on cell membranes called lipid rafts form because

#Section 2: General Biology

  1. membrane proteins form them.

  2. cholesterol preferentially associates with sphingolipids.

  3. certain membrane protein patches aggregate.

  4. cholesterol and proteins bind to form them.

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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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TLS Online TPP Program

#Question id: 14223

#Section 5: Bioprocess Engineering and Process Biotechnology

A furnace wall is constructed of firebrick 15-cm thick. The temperature inside the wall is 700⁰C the temperature outside is 80⁰C. If the thermal conductivity of the brick under these conditions is 0.3 W m-1 K^-1, what is the rate of heat loss through 1.5 m2 of wall surface?
TLS Online TPP Program

#Question id: 14224

#Section 5: Bioprocess Engineering and Process Biotechnology

Heat is transferred from one fluid to a second fluid across a metal wall. The film coefficients are 1.2 and 1.7kW m^-2 K^- 1. The metal is 6-mm thick and has a thermal conductivity of 19 W m^-1 K^-1. On one side of the wall there is a scale deposit with a fouling factor estimated at 19 W m^-1 K^-1. What is the overall heat-transfer coefficient?
TLS Online TPP Program

#Question id: 14225

#Section 5: Bioprocess Engineering and Process Biotechnology

A fermenter is maintained at 35⁰C by water circulating at a rate of 0.5 kg s^-1 in a cooling coil inside the vessel. The inlet and outlet temperatures of the water are 8⁰C and 15⁰C respectively. The length of the cooling coil is increased by 50%. In order to maintain the same fermentation temperature, the rate of heat removal must be kept the same. Determine the new cooling-water flow rate and outlet temperature by carrying out the following calculations. The heat capacity of the cooling water can be taken as 4.18 kJ kg^- 1 o C^- 1. From a steady-state energy balance on the cooling water, calculate the rate of cooling with the original coil ___________________.
TLS Online TPP Program

#Question id: 14226

#Section 5: Bioprocess Engineering and Process Biotechnology

A fermenter is maintained at 35⁰C by water circulating at a rate of 0.5 kg s^-1 in a cooling coil inside the vessel. The inlet and outlet temperatures of the water are 8⁰C and 15⁰C respectively. The length of the cooling coil is increased by 50%. In order to maintain the same fermentation temperature, the rate of heat removal must be kept the same. Determine the new cooling-water flow rate and outlet temperature by carrying out the following calculations. The heat capacity of the cooling water can be taken as 4.18 kJ kg^- 1 o C^- 1. Determine the mean temperature difference with the original coil.
TLS Online TPP Program

#Question id: 14227

#Section 5: Bioprocess Engineering and Process Biotechnology

A fermenter is maintained at 35⁰C by water circulating at a rate of 0.5 kg s^-1 in a cooling coil inside the vessel. The inlet and outlet temperatures of the water are 8⁰C and 15⁰C respectively. The length of the cooling coil is increased by 50%. In order to maintain the same fermentation temperature, the rate of heat removal must be kept the same. Determine the new cooling-water flow rate and outlet temperature by carrying out the following calculations. The heat capacity of the cooling water can be taken as 4.18 kJ kg^- 1 o C^- 1. Evaluate UA for the original coil. ________________