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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BIOCHEMICAL ENGINEERING INSTRUMENTATION - EXAMPLE 29.5 : The following formula is used as a reference : (analyte signal) / (internal standard signal) = (f-factor) x (concentration of analyte) / (concentration of internal standard). A solution containing 3 mM of analyte and 4 mM of internal standard gave peak signals of 2 and 3 mamps respectively. Another similar solution containing 2 mM of analyte and 1 mM of internal standard gave peak signals of 1 and 4 mamps respectively. Find the average f-factor.

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QUANTUM BIOLOGY - EXAMPLE 33.1 : In quantum biology, conditional entropy is given by H (S | O) = H (SO) - H (O). With reference to such equation, find another equation for H (SA).

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Explain how can one estimate how the friction factor changes in heat exchanger tubes with a change in temperature?

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DIFFERENTIAL EQUATIONS - EXAMPLE 20.1 : By using Excel program either on laptop or desktop PC, solve the differential equation dy / dx = -2y + x + 4 with h = 0.005, initial values : x = 0, y = 1. The 4th order Runge-Kutta method provides : y(N + 1) = y(N) + (1/6) (k1 + 2k2 +2k3 + k4), k1 = h [ -2y(N) + x(N) + 4 ], k2 = h { -2 [ y(N) + k1 / 2 ] + x(N) + h / 2 + 4 }, k3 = h { -2 [ y(N) + k2 / 2 ] + x(N) + h / 2 + 4 }, k4 = h { -2 [ y(N) + k3 ] + x(N) + h + 4 }. What is the value of y at x = 0.5?

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sir i am appearing in railway exam of section engineer and my branch is chemical engineering i want previous question paper of section engineer of chemical branch please tell me as soon as possible my email id is surendrasaroj18@gmail.com THANKYOU

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Explain the factors involved in considering the choice of dry screw compressor?

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why we messure differential pressure in pascle,mmhg,mmwc like different units in different companys?

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hi can anyone tell me some technical questions asked in iocl

0 Answers   GACL, IOCL,

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y we do not differ b/w atomic mass and atomic wieght? from engrtauseef2008@gmail.com

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What are the greenhouse gases in earth's atmosphere?

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What is a good source of equations for calculating discharge flowrates from accidental releases?

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