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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Explain what are the methods involved to test helium leak testing in a vacuum system?

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Explain why is post-weld heat treatment (stress relieving) sometimes necessary for welded vessels?

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What are the chemicals are required for cooling tower passivation? Please mail me in my Email id:-nsput2000@gmail.com

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What are some characteristics of bulk solids that can affect their ability to flow properly?

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we have 2 O2/Comb Analyzers Servomex Model 2700 in service for one of the furnaces in our chemical plant. It is giving High Temperature Alarm. Checked Temperature and found it to be 800 Deg C whereas Set Point is 700 Deg c. It is strange why is temperature not at SP. Also response is 23 % with 21 % Inst Air and with N2 reading is not coming down. please clarrify this issuses very urgent

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Question 106 - In a wavefunction, let P(x) = A cos kx + B sin kx. By using the boundary conditions of x = 0 and x = l, where P(0) = P(l) = 0, prove by mathematical calculation that P(x) = B sin (npx / l) where p = 22 / 7 approximately, n is a rounded number. A, B and k are constants.

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Explain the some guidelines for sizing a psv for a fire scenario on a vessel in a refinery service?

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When specifying a cooling tower, should I look up historic wet bulb temperatures for my area or should I take measurements?

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how to calculate overall heat transfer coefficient in insulated pipeline? Please give a answer with formula

2 Answers   NPCIL,

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Why does catalytic converter used in an automobile?

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what is zeroth law ?

6 Answers   ISRO,

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