Focus including gas and liquid chromatogra phy with inductively coupled plasma detection. Chemometrics
Bruce Kowalski of the University of Washington makes a careful distinc tion between the concentration deter mined from a calibration curve and the truth. If you just want to do cali brations to determine concentrations, there's not much chemometrics can do for you, according to Kowalski. But if you're interested in the truth—how much of an analyte is really in the sample—then information science has lots to offer. "We're going to have a turn towards truth in analytical chemistry," Kowal ski said. "We're not going to have the analytical chemist in his lab running a calibration curve, knowing full well that the water he's using to run his calibration has nothing to do with the real sample, and that he's got tremen dous matrix effects." There are meth ods from information science, he ex plains, that will enable the chemist to find true concentrations, even in the presence of both matrix effects and in terferences.
Referring to computerized instru mentation, Kowalski pointed out that today's instruments are still rather dumb. "They have big computers, and sometimes you're overbuying the com puter you're getting (sorry if I said something unpopular). But the com puters are doing rather simple things, in many cases just the things analog electronics used to do: simply collect data and print it out," he said. There's going to be more of a bal ance in the 1980s between the time it takes to separate out a mixture by in strumental chromatography and the mathematical resolution of signals. For example, in GC/MS, multivariate statistical methods can determine if two unresolved components are hiding together underneath one peak. And now there's a method to separate the components mathematically (ANAL. C H E M . , 1981,53, 518-522). "So why
put so much burden on the GC?" asked Kowalski. "Shorten the analysis and let the computer have the balance of the resolution." Surface Chemistry The solid/ultrahigh vacuum (solid/ UHV) interface continues to be the
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