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LIVE WITH: PURITAN The new IWT Puritan Cartridge is the last word in de-ionizing purity. Because of its spongelike porous surface, the resin bead removes 90% of particles 0.1 micron or larger, including colloidal silica. Water that pure, you couldn't live with since it would pick up impurities from anything it touched. That's why you must make it up fresh from an IWT Cartridge System. It could extend the life of your submicron filters from 10 to 50 times or more—a real money saver! Such purity is needed for electronics and lab use: 15 megohm water with 90% suspended solids removed!
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Instrumentation
(3) Easy transfer of data to a larger computer. (4) Computer correction of data for experimental error. (5) Computer interpretation of data. (6) Digital storage of data for later retrieval, interpretation, and compari son with new results. At least two trends in computerized analytical chemistry are already dis cernible. New types of research studies are being directed to methods of making use of more information in the analytical signal. When such re search was done earlier, it was chiefly of academic interest because the mea surements and computations would have required too much time for most applications. New instruments and computer methods eliminate the time restriction (in fact, less time may be needed to measure more data and do more calculations). Acceptance of the new methods requires only that ad vantages be demonstrated to justify the extra costs. Such demonstrations al ready have been made in several cases. A second trend is toward more so phisticated control of the instrument by the computer. Presently, the computer is programmed to operate the instru ment by a fixed scheme. The computer potentially can be programmed to alter the experiment in response to analysis of the data being recorded. When this is done, the analytical chemist will specify the desired results to the in strument, rather than stating how the measurements are to be made. At the same time, the computer will be check ing the instrument operation. It will monitor several components directly, as is now being done in a few instances, and also will analyze the output for other signs of malfunction. When these tests indicate an instrument malfunc tion, the computer can terminate the measurement process and indicate to the operator the nature of the disorder. The extra cost for these operations would be regained by more efficient in strument operation.
References
(1) H. Cole, IBM J. Res. Develop. 13, 5 (1969). (2) Heinrich Kaiser, ANAL. CHEM. 42 (2),
24A (1970). (3) Marvin Margoshes, Spectrochim. Acta 25B, 113 (1970). (4) A. W. Helz, F. G. Walthall, and Sol Berman, Appl. Spectrosc. 23, 508 (1969). (5) Marvin Margoshes, Pittsburgh Con ference on Analytical Chemistry and Applied Spectroscopy, Cleveland, Ohio, March 1970. (6) M. J. D. Low, ANAL. CHEM. 41 (6),
97A (1969).
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SPECTRIN! Cryocooîing Module
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ANALYTICAL CHEMISTRY, VOL. 43, NO. 4, APRIL 1971 ·
109 A
