MICROBIOLOGICAL ENGINEERING - QUESTION 28.1 : In the calculation of the growth of bacteria, colony forming unit (CFU) in serial dilution is used. In a laboratory, viable count assay is used to estimate CFU. Formula applied is CFU / mL = (number of colonies x dilution) / (amount plated, in unit mL). Acceptable plate count is either between 20 and 200 or between 30 and 300 according to 2 different references. A wastewater sample of 200 ml is added to and mixed with 1.8 L of sterile water. Another 200 ml of the mixture is added to and mixed with 1.8 L of sterile water. (a) Calculate the dilution of first mixture and the dilution of the second mixture. (b) 100 microlitres of wastewater samples from the first mixture and the second mixture are placed separately on 2 different alga plates. The first plate has 250 colonies and the second plate has 23 colonies. Calculate the average CFU / mL.

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PETROLEUM ENGINEERING - QUESTION 25.2 : (a) The American Petroleum Institute gravity, or API gravity, is a measure of how heavy or light a petroleum liquid is compared to water. Let SG = specific gravity of petroleum liquid, and V = barrels of crude oil per metric ton. Given the formula for API gravity = 141.5 / SG - 131.5 and V = (API gravity + 131.5) / (141.5 x 0.159), find the relationship of SG as a function of V. (b) An oil barrel is about 159 litres. If a cylinder with diameter d = 50 cm and height h = 50 cm is used to contain the oil, find the volume V of the cylinder in the unit of oil barrel by using the formula V = 3.142 x d x h x d / 4. (c) First reference : 1 cubic metre = 6.2898 oil barrels. Second reference : 1 cubic metre = 6.37 oil barrels. What are the 2 factors that cause the difference in such reference data?

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how to calculat suction head in centrifugal pump?

2 Answers   IOCL,

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What type of pump may be appropriate for a liquid near saturation, a low flow rate, and very limited npsha?

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What is pneumatic conveying?

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How much water is lost through a commercial cooling tower system with a throughput of about 600 gpm?

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Why does catalytic converter used in an automobile?

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what is flooding in a column.How do you know flooding has occured?

2 Answers   Cairn,

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Are there any special considerations to be taken into account for combusting ammonia?

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What are the main terms in unit operations? What are its characteristics?

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In engineering economy, the future value of first year is FV = PV (1 i). For second year it is FV = PV (1 i) (1 i). For third year it is FV = PV (1 i) (1 i)(1 i) where FV = future value, PV = present value, i = interest rate per period, n = the number of compounding periods. By induction, what is the future value of $1000 for 5 years at the interest rate of 6%?

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Hi, I am preparing for Indian Forest Service (UPSC). Can you please help me to get previous years question papers (Chemcial Engineerign) (atleast 5).

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