Spreadsheet rate calculation

The blood alcohol content of an individual is determined enzymatically by reacting ethanol with NAD" in the presence of the enzyme alcohol dehydrogenase to produce NADH (Table 22.1). The rate of formation of NADH is measured at 340 nm (Figure 22.4). The following absorbances are recorded for a 0.100% (wt/vol) alcohol standard and the unknown, treated in the same way. Use a spreadsheet to calculate the rates of absorbance changes and from these, the unknown concentration. 

Statement, together with an Excel spreadsheet, to calculate the total amounts of substrate and biomass present at any of the indicated times, recognizing that at any time these totals are equal to the product of the volume of the cell-free growth medium and the corresponding concentration of biomass or glucose. The results of these calculations are summarized in Table 113.1-2, which also contains estimates of the total rates of consumption of substrate (-%) and production of biomass ( Kx) hat were obtained by simple numerical differentiation of the appropriate entries in Table 113.1-2 for example. 

Column 12 is used to classify the failure mode with a designation. If only two modes are needed, a "1" and a "0" could be entered. If multiple failure modes are needed, letters can be entered. The failure mode designator can be used in spreadsheets to calculate the various failure rate categories. In Table E-2 only two failure modes are designated, safe and dangerous. 

To use Table 61.2, which is based on the formula 1/(1 -b 0" 5 where i is the rate of interest and n is the number of years, the relevant factor is found for the rate and number of years and multiplied by the amount for which the NPV is required. Thus to find the NPV for 1500 receivable in 5 years at 10 per cent from the table is found the factor of 0.621 and this, multiplied by 1500, gives an NPV of 931.5. Most spreadsheets used on personal computers include a formula for calculating NPV, so avoiding the need to construct tables. 

The heat balance exercise provides a tool for in-depth analysis of the unit operation. Heat balance surveys determine catalyst circulation rate, delta coke, and heat of reaction. The procedures described in this chapter can be easily programmed into a spreadsheet program to calculate the balances on a routine basis. 

The rate constant for the alkyl bromide reaction is equal to the slope of the line. The best way to determine a slope is by doing a linear curve fit using a spreadsheet or graphing calculator. Somewhat less accurately, any two points on the line determine the slope ... 

By constructing a plot of S(t,) versus Xvdt, we can visually identify distinct time periods during the culture where the specific uptake rate (qs) is "constant" and estimates of qs are to be determined. Thus, by using the linear least squares estimation capabilities of any spreadsheet calculation program, we can readily estimate the specific uptake rate over any user-specified time period. The estimated... 

Using the data given below, draw an information flow diagram of the process and calculate the process stream flow-rates and compositions for the production of 600 t/d ammonia. Use either the Nagiev split fraction method, with any suitable spreadsheet or manual calculations. 

The following provides cost information (expressed in fourth-quarter 1993 dollars) for retrofitting an existing scrubber system with a condensation scrubber under typical operating conditions, adapted from EPA cost-estimating spreadsheets (EPA, 1996) and referenced to the volumetric flow rate of the waste stream treated. For purposes of calculating the example cost effectiveness, the pollutant is PM at a loading of approximately 7 g/sm3 or 3 gr/scf. The costs do not include costs for post-treatment or disposal of used solvent or waste. 

Given a suitable algebraic correlation such as equation 2.19, the friction factor chart might be considered obsolete. Both / and fRe2 can be represented algebraically as functions of Re allowing both types of calculations to be done. In the case of the inverse problem, that is the calculation of the flow rate for a specified pressure drop, an alternative is to use an iterative calculation, a procedure that is particularly attractive with a pocket calculator or a spreadsheet. Using equation 2.19 for /, the procedure is as follows ... 

The spreadsheet in Figure 4-62 is heavily matrix based (see Chapter 2, for an introduction to basic matrix functions in Excel). It is the only way to keep the structure reasonably simple. The matrix C in cells A21 C31 is computed in the usual way, see equation (4.63) the parameters required to compute the concentration matrix are in cells Q4 S4, they include the initial concentration for species A and the two rate constants that are to be fitted. In cells E 16 018 the computation of the best absorptivity matrix A for any given concentration matrix C, is done as a matrix equation, as demonstrated in The Pseudo-Inverse in Excel (p.146). Similarly the matrix Ycaic in cells E21 031 is written as the matrix product CA. Even the calculation of the square sum of the residuals in cell R7 is written in a compact way, using the Excel function SUMXMY2, especially designed for this purpose. We refer to... 

As indicated by Eq. 15-36, to estimate the rate of direct photolysis of a pollutant in a given system, one needs to know the k3 value as well as the reaction quantum yield for the compound considered. As we have extensively discussed, k3 values may be estimated with the help of spreadsheet calculations or computer programs. However,... 

Suggestion Near the top of the spreadsheet, enter the values of a b.c.d, and e for each species. Starting several rows below the last of these entries, list in Column A labels for the input variables and all calculated variables (component molar flow rates, specific enthalpies, rad.ao, ,- ., 0f4,A//), and enter in adjacent columns the corresponding values or formulas for these variables in successive runs. Solution for Run 1 = 1743.1°C.)... 

The spreadsheet shows an initially assumed value of the recycle flow rate (ha) of 100.0 mol/s (Cell E13) and an assumed value of the mixing point outlet temperature of 50°C (Cell D8). The value of hi will be varied until the calculated recycle flow rate (/i4c) in Cell J13 equals the assumed value, which it now does not. (The actual calculation will be done by finding the value of 4a that drives the value of ha - ha in Cell 117 to zero.) Once the flow rates are correct, the mixing point temperature will be varied to determine the value that drives A// = S out out (in Cell D4) to zero for the adiabatic mixer. 

As an exercise, after you have familiarized yourself with the material in the next chapter, you might want to try to write such a function. It should have as its input the previous concentrations, the rate parameters, and the time increment. It should then calculate (for this specific reaction scheme) the concentrations at time t+ At, and write these concentrations back onto the spreadsheet. Use the matrix inversion subroutine for the hard work. 

Prepare a spreadsheet for a Lineweaver-Burk plot and calculate the maximum rate and the Michaehs constant... 

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