Virtual Instrument Technology Research And Its Applications In Analytical Chemistry

The concepts, characteristics and components of visual instruments(Ⅵ) were introduced particularly and the implementation of system basedonⅥis discussed in the dissertation. The data acquisition system withLabVIEW and Visual Basic respectively and the control system based onsingle-chip were studied, and they were applied in flow injection analysis,automatic electric potential titration and cyclic voltammetry so that usercustomization was realized. The characteristics ofⅥdetermine that thesystem is more flexible and has wider application fields.With LabVIEW and VB programs, the control of data acquisitionmodule, and signals sampling, data display, data analysis, data saving inPC ware realized. Their key techniques in realizing processes arediscussed. At the same time, with the development of AT89C51 singlechip microcomputer, the controls of peristaltic pump, electromagneticvalve and other hardware by PC were realized.A flow injection analysis system based onⅥwas developed.Employed flow injection sulfuric acid and carbazole spectrophotometricdetermination of pectin in tobacco leaf using stopped-flow technique. Thebest condition was gained: the volume of tube is 204μL; Thedetermination wavelength is 540 nm; The content of carbazole is 0.15%;the time of liquid calefaction is 5 min. An automatic electric potentialtitration system based onⅥwas developed. Employed acid-base titrationto measure average numbers of primary and tertiary amine groups inPAMAM, the determination result reaches agreement with theoretic value,and the disfigurement and purity of synthetical PAMAM werecharacterized accurately. A cyclic voltammetry system based onⅥwasdeveloped, cyclic voltammetry determination of potassium ferricyanidewas employed. The output of cyclic voltammetry curves recorded by PCis more accurate and convenient in application than by X-Y recorder.Besides, by the application ofⅥtechnology, the author probed intothe efficient approach of developing computerized measuring instrument systems in analytical chemistry.