Software spreadsheets

The equilibrium diagram in Fig. 7.2 is considerably different from the triangular diagram in Fig. 7.1. It is the same extraction liquid-liquid equilibrium, with water the feed-raffinate, benzene the solvent-extract, and acetic acid the solute. The complete solution has been performed in Microsoft Excel, but other commercial software spreadsheets may also be used. Please notice first, as shown in the boxed area in columns A and B, that the equilibrium curve data have been entered. Next we will see how such a curve is made. 

All review sessions should be recorded using a personal computer (PC). Word processing software should be used for the report narrative write-up. A computer software spreadsheet, prepared for process safety reviews, should be used for all HAZOP and What-If reviews. It facilitates speed, ease of use and maintains exact consistency in format. 

Standard application software Spreadsheets, statistical packages, word processor Bug fix, patch, new version in the standard application software... 

The software spreadsheets contained in this disk are implementations of the examples worked in this book. These spreadsheets must be used in conjunction with this text and are not designed as a stand alone product. 

Although equations 5.13 and 5.14 appear formidable, it is only necessary to evaluate four summation terms. In addition, many calculators, spreadsheets, and other computer software packages are capable of performing a linear regression analysis based on this model. To save time and to avoid tedious calculations, learn how to use one of these tools. For illustrative purposes, the necessary calculations are shown in detail in the following example. 

This is a more difficult equation to solve than that for the solubility of Pb(I03)2 in distilled water, and its solution is not immediately obvious. A rigorous solution to equation 6.34 can be found using available computer software packages and spreadsheets. 

A number of statistics and spreadsheet software packages are available to perform ANOVA calculations. 

Many of the topics covered in analytical chemistry benefit from the availability of appropriate computer software. In preparing this text, however, I made a conscious decision to avoid a presentation tied to a single computer platform or software package. Students and faculty are increasingly experienced in the use of computers, spreadsheets, and data analysis software their use is, I think, best left to the personal choice of each student and instructor. 

Additionally, solutions to problems are presented in the text and the accompanying CD contains computer programs (Microsoft Excel spreadsheet and software) for solving modeling problems using numerical methods. The CD also contains colored snapshots on computational fluid mixing in a reactor. Additionally, the CD contains the appendices and conversion table software. 

Calculations of life-cycle costs, net benefits, or other measures of economic performance are commonly performed on electronic calculators, commercial spreadsheet software, or by hand. The calculation approach for life-cycle costs is to first compute the net cost amount in each period for each alternative, C(t,x). The life-cycle cost (LCC) of each alternative is then calculated as the sum of the discounted values of C(t,x) over the entire planning horizon ... 

Kumana, J. D., Run Batch Distillation Processes with Spreadsheet Software, Chem. Eng. Prog. Dec. (1990), p. 53. 

The introduction of computers to many companies allows proprietary software to be used for layout design. Spreadsheet, mathematical modeling and computer-aided design (CAD) techniques are available and greatly assist the design process, and have added to the resources available to planners. However, the traditional scale models described above will still be useful to present the result to management and shop floor personnel. 

Validation also applies to software. In a simple example, you could create an Excel spreadsheet template with fixed formulae to calculate the mean and standard deviation of a range of data. To validate this template you would enter a set of sample data and verify the template-calculated results against the manually calculated results. In order to be confident that the template could be used for further data sets you would password-protect the cell formulae and verify that they cannot be altered without it. 

Within the pharmaceutical industry we have progressed from the point where computers in the laboratory were rarely present or used beyond spreadsheet calculations. Now computers are ubiquitous in pharmaceutical research and development laboratories, and nearly everyone has at least one used in some way to aid in his or her role. It should come as no surprise that the development of hardware and software over the last 30 years has expanded the scope of computer use to virtually all stages of pharmaceutical research and development (data analysis, data capture, monitoring and decision making). Although there are many excellent books published that are focused on in-depth discussions of computer-aided drug design, bioinformatics, or other related individual topics, none has addressed this broader utilization of... 

An additional requirement not noted in Table 1 is compliance with GLP7 These practices establish a paper trail for all procedures involved in the determination of residues. With regard to immunoassays, GLPs require calibration of measurement devices such as adjustable pipettors and dedicated spectrophotometers. Computer software output, as noted above, must be verified prior to use. This process can be simplified by limiting the application of specialized software to the operation of an instrument and carrying out the residue calculations in a broadly available spreadsheet such as Excel. On a positive note, in recent years, the software accompanying most microtiter plate readers has become generally easier to use and usually incorporates internal spreadsheets that are compatible with external systems. 

As will be seen later, these techniques will prove to be useful when solving design problems in general-purpose software, such as spreadsheets. Many of the numerical problems associated with optimization can be avoided by appropriate formulation of the model. Further details of model building can be found elsewhere12. 

Simple phase equilibrium calculations, like the one illustrated here, can be readily implemented in spreadsheet software and automated. In practice, the calculations will most often be carried out in commercial physical property packages, allowing more elaborate methods for calculating the equilibrium K-values to be used. 

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