8.  Assuming the laminar flow across the filter, the rate of filtration (dVf/dt) can be expressed as a function of pressure drop Dp by the modified D'Arcy's equation as (where A is the area of filtering surface, K is the D'Arcy's filter cake permeability and L is the thickness of the filter cake)
A.(1/A) dVf/dt = Δp/μ(L/K)
B.dVf/dt = (1/A)Δp/μ(L/K)
C.(1/A) dVf/dt = Δp/μ LK
D.dVf/dt = (1/A)Δp/μ LK

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9. Filtration leaf test results indicate that the filtration rate of a protein product is 100 dry lbs/(ft2 hr). What size production filter would be required to obtain 100 dry lbs of filter cake/hr?
A.1.54 ft2
B.3.08 ft2
C.65 ft2
D.65 lbs/ ft2.hr

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10. Selectivity can be expressed as
A.ratio of the distribution coefficients in different solute
B.mass fraction of the solute in the extract phase at equilibrium
C.mass fraction of the solute in the raffinate phase
D.ratio of the mass fraction of the solute in the extract phase to the raffinate phase

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11. The disk centrifuge is the type of centrifuge used most often for bio separations due to its
A.continuous operation
B.lesser cost
C.higher speed
D.ease in operation

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12. The effectiveness of a solvent can be measured by the
A.distribution coefficients
B.selectivity
C.both (a) and (b)
D.diffusivity

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13. The stage wise operation of adsorption is called
A.contact filtration
B.conventional adsorption
C.affinity adsorption
D.ion exchange

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14. Which of the following is not the physical method for the cells rupturing?
A.Milling
B.Homogenization
C.Ultrasonication
D.Enzymatic digestion

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