user must enter initial best guesses for the variables. Useful features include the ability to set constraints on variables, the errorhandling routines [preventing a program crash], and the ability to do m g e solving, where one variable mav,be held constant to ohtaina solution, then rariedasa parameter tc. obtain a cumplete set of solutiunr, as in calrulntingatitrnri~rncurve.Results may he graphed, and graphs, solutions, and equations sets may be saved far later reference. The documentation is supplied in e manual and appears to be quite complete and clear. I t indudes a chemistry example [species concentrations in a solution of a triorotic soeeies , ~~~-~as a function of oH1. There is no dorumentationor helpsupplied from wrthiu the p n w a m itself. No index is avaiinhle in the manual, but the Table of Contents is quite complete and can replace an index. The program behaves as described when using the examples given in the manual. SEQS requires uoapecial set-up. Requirements are DOS 2.x to 4.x. and 640K memory is highly recommended, especially with DOS 4.x. When the program is run, a short title screen first comes up. I t is followed by a small colorful screen described a s the Main Menu, giving a choice of function keys to be pressed to proceed. All other menu screens are presented in the same rather ambiguous format. Unless the manual has been studied closelv. ~, .much confusion can arise here. I t is a g w d idea to follow through all ofthe tutorials i n the manual hefore trying to use the program. Moving around in the program is easy and apparently foolproof. We never had it hang up from pressing the wrong key. In most cases, error statements pop up to explain errors, and corrections are given. Inuut is relativelv easv. . The user first types in the equotiom to be solved. Then, valuer are assigned to all quentifieri. Finally, each quantity is assignrd tcr be a ronstanr ur a variable. The solution process then proceeds. The solution process can be halted at any time to review or modify the equations or values. The versatility in giving names to variables should esoeciallv be anureciated. .. Concentrations, for example, can be denoted by brackets surrounding the chemical formula. Equations may include any standard mathematical function, ranging from square root to complex trigonometric funetions. The program includes more of these than are included in most high level programming languages. I t is not possible tolist or modify the program. SEQS is a general equation solving program, and, therefore, is applicable in a wide variety of situations. The solutions arrived at for chemical equilibrium problems and for a titration curve, at least, appear to he accurate, and agree with solutions arrived at by other methods. The course of iteration when determining a solutioncan be followed on the screen if desired, another useful feature. The SEQS program was given to students in the second semester of Physical Chemistry ttr review. They were asked to use it on their own, since the student version was supplied. The student reaction was generally not very positive. They found the pro~
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A150
Journal of Chemical Education
gram hard to use, especially in the Range Solve mode [where a parameter is varied to obtain a set of solutions]. The absence of help when running the program appeared to be part of the problem. Also, since equations must he entered before variables and constants are defined, the program appears to treat every quantity as a variable initially, which is confusing. One student commented that it wes not very useful for "practical" applications. Two factors would greatly improve this program. Firat, help should be available from the program, even if it is stored on the disk for reference as needed. Most word pracessors, for example, have such help available, as do many other programs such as spreadsheets. Secondly, the symbols for variables, parameters, and constants could be input before the equations are typed in, to prevent confusion and encourage students to carefully define their system. SEQS is a versatile equation solving program but appears to have rather limited use for students. The students who reviewed it have become rather good spreadsheet users during the last year and generally felt that most of what SEQS did could he done an a spreadsheet more easily. Indeed, they have calculated titration curves and have done most of their laboratory data reduction on a spreadsheet this year. Considering the cost of the program, and its limited utility to students, a shareware spreadsheet such as ASEASYAS (Lotus 1-2-3 compatible costs about $45 for a registered copy) by Trius, Inc. of North Andover, Massachusetts, is to be preferred. I t has, in addition to the usual spreadsheet features, the ahility to do matrix manipulation, solve simultaneous linear equations and perform linear regression, which most spreadsheets do not have. Articles on using spreadsheets to solve chemical equilibrium problems, like those that SEQS can solve, were presented recently in thts Journal (I). In addition, a recent issue of Journal of Chemical Education: Software described the use of spreadsheets in Physical Chemistry, and included templates for many common topics (2). One pedagogical objection to the program is that it removes the student one step further away from a knowledge of chemical equilibrium. A student need not know that a buffer solution is formed during an aeidbase standardization titration, or that at the endpoint the solution consists of a single salt, for example. All that is necessary is to type in the equations and assign values. On the other hand, to get the program to give a complete solution often requires considerable experience or advanced knowledge of what should happen. We could not get the general equations far a titration curve to give a correct solution if the volume of added titrsnt was zero. An instructor would understand why this happens. For a student it could lead to considerable frustration. Having acopy of SEQS available [the professional version] makes sense, however. In research or general advanced class work, the necessity of solving sets of complex, seemingly intractable equations can arise. Usually, without a program like SEQS, the solutions would be difficult if not impossible. Having SEQS available promotes the solution of problems that otherwise might not be attempted but could lead to interesting insights or conclusions.
I. Cad W. David, J . Chom.Educ 1989.66, A237 Stephen LPharne, J. Chem Edue. 1989. 66. A239; Clyde Metz and HanryDanafo,Jr.. J . Chem.Educ. 1989.66.A241. 2. David W. Whimant, Journnl of Chemical Education: So/iuore 198%JIB Na 1
K. E. Dierenteldt COncoMia College Maorhead. MN 56562 The Language of Blotechnology: A Dlctlonary of Terms John M. Walker and Michael Cox. American Chemical Society: Washington. DC. 1988. viii 255 pp. 14.6 X 22.6 cm.
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$49.95. HB $29.95 PB.
Today few science-related areas figure as prominently in the news medra as biotechnolow, defined by the lexicographers ofthis volume as "the practical application of biblogical systems-to the ma&facturing and service industries and to the management of the environment." As a recent hook review aptly points out (MacQuitty, J. J. Chem. Eng. News 1990,68(3), 42)), communicating hiotechnology to the nonexpert is difficult hut vital. Yet the problem goes deeper than this. Despite the widespread interest in biatechnology, the problem of understanding it applies to scientists as well as the general public. The field is so broad and uses the techniques of so many specialized areas (e.g., molecular biology, microbiology, pharmacology, biochemistry, organic chemistry, and chemical engineering) that scientists frequently work in interdisciplinary groups, involving researchers educated in different areas and approaching their projects with different backgrounds and different vocabularies. The authun of this dictionary under review, both readers at the Hatfield Polytechnic. Hatfield, Herts. England, have a t rempted -succrssfully in my pinion-"to define routinrly used apecralized language in the various areas irf bLtechnoloa\." so as to standardize the terminology i n i d a common language and thus help workers understand the language or jargon of their collaborators. Despite its size constraints, the volume offers lucid, authoritative definitions of a wide and balanced selection of termsfrom "abomasum" to "zygomycotima"-from the various fields most likely to cause communication problems in an interdiseiplinary research group. Replete with clear equations and diagrams, it deals with terms and concepts from microhial biochemistry and physiology, molecular biology and genetics, genetic engineering, animal and plant cell culture, enzyme and protein technology, fermentation technology, biochemical engineering, process control, downstream processing, and waste and environmental toxicology. This ACS Professional Reference Book deserves a prominent place on the shelf of biotechnolagical research and development firms as well as university and professional libraries. I t also belongs in the reference collection of any scientist or educator who must communicate with colleagues in other fields. George B. Kauffman Califmla State University. Fresno Fresno. CA 93740
