REACTION ENGINEERING - EXAMPLE 13.3 : The half-life for first order reaction could be described in the differential equation dC / dt = -kC where k is a constant, C is concentration and t is time. (a) Find the equation of C as a function of t. (b) Find the half life for such reaction or the time required to reduce 50 % of the initial concentration, where k = 0.139 per minute. (c) When the initial concentration Co is 16 mol / cubic metre, how long does the reaction required to achieve the final concentration of 1 mol / cubic metre?

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ACCOUNTING AND FINANCIAL ENGINEERING - EXAMPLE 34.28 : In the development of a small engineering facility for biochemical processing, completed contract method is applied in its construction accounting. In a short contract period, let the (contract price) = A. Let the (costs to date) = B; (estimated cost to complete) = C. (a) Find the values of : (i) estimated total costs; (ii) total estimated profit; (iii) percent completion to date. (b) If the project contract is 100 % completed : (i) find the total gross profit recognized; (ii) what is the exact numerical value of C?

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When should one be concerned with the tube wall temperature on the cooling waterside of a shell and tube exchanger?

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can i drink deminaralised?

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ENGINEERING NUMERICAL METHODS - EXAMPLE 19.3 : There are 2 simultaneous equations : (A1) x + (B1) y = D1 and (A2) x + (B2) y = D2. (a) By using Excel program, find the values of x and y when A1 = 80, A2 = 150, B1 = 52, B2 = 100, D1 = 3.5 and D2 = 2.3. (b) Write the expression of Excel in the form of =MMULT(MINVERSE(W:X),Y:Z) in order to get the values of x and y. W, X, Y and Z may be A1, A2, B1, B2, D1 and D2.

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Define a solvent?

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How can wet carbon dioxide be responsible for a corrosion problem in iron-containing metals?

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

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QUANTUM COMPUTING - EXAMPLE 32.9 : In quantum computing, find the equations of S = (a | 0 > + b | 1 >) (g | 0 > + d | 1 >) in term of | 00 >, | 01 >, | 10 > and / or | 11 > when ad = 0.

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NATURAL GAS ENGINEERING - QUESTION 26.1 : (a) In natural gas pipe sizing, the length of the pipe from the gas source metre to the farthest appliances is 60 feet. The maximum capacities for typical metallic pipes of 60 feet in length are : 66 cubic feet per hour for pipe size of 0.5 inches; 138 cubic feet per hour for pipe size of 0.75 inches; 260 cubic feet per hour for pipe size of 1 inch. By using the longest run method : (i) Find the best pipe size needed for the capacity of 75 cubic feet per hour. (ii) Estimate the suitable range of capacities for the pipe size of 1 inch. (b) The maximum capacities for typical metallic pipes of 50 feet in length are : 73 cubic feet per hour for pipe size of 0.5 inches; 151 cubic feet per hour for pipe size of 0.75 inches; 285 cubic feet per hour for pipe size of 1 inch. By using the branch method find the best pipe size needed for the capacity of 75 cubic feet per hour when the length of the pipe from the gas source metre to the appliance is 52 feet.

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What is critical radius of insulation?

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A cylinder with a movable piston contains 0.1 mole of a monoatomic ideal gas. The piston moves through state a, b and c. The heat Q, changes from state c to a is 685 J. The work W, changes from state c to a is -120 J. The work, W performed from state a to b then to c is 75 J. By using the first law of thermodynamic, U = Q W where U is the internal energy : (a) Determine the change in internal energy between states a and c. (b) Is heat added or removed from the gas when the gas is taken along the path abc? (c) Calculate the heat added or removed when the gas is taken along the path abc?

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