A microcomputer-controlled background correction system for atomic spectrometry

Abstract

A novel instrument system has been designed for use in atomic spectrometry. An Apple microcomputer is used to control data acquisition and perform data processing in a single-channel spectrometer system, which may be applied to continuum-source atomic-absorption or atomic-emission measurement. Wavelength modulation, a rapid, repetitive scanning procedure, is employed to perform automatic background correction under computer control. The microcomputer programs are written in BASIC with incorporated assembly language subroutines. The system may be used in a steady-state atomisation mode (e.g., flames) or in a transient atomisation mode (e.g., electrothermal atomisers) for either absorption or emission measurement. The microcomputer program provides peak-height and peak-area data simultaneously and a procedure is available that allows the extension of the linear calibration range. Detection limits obtained using the system are comparable to previously reported values. The software organisation and operating procedures are described and illustrated using typical output signals measured by the system. Keywords : Con tin u um -source a tom ic absorption; a tom ic emission ; microcomputers; flames; background correction * Detailed information on the software described in this paper can be obtained from the authors on request.

Continuum source atomic absorption spectrometry in a graphite furnace with photodiode array detection

“…Sample Preparation. Stock solutions (1000 mg/L in 2% HNOa) were obtained from Inorganic Ventures, Inc. (Brock, NJ) for the 19 elements tested. A mixture of these elements (each element 10 mg/L) was prepared, and dilutions were made as necessary to obtain analytical calibration curves.…”

“…Analytical Figures of Merit. Detection limits for the 19 elements tested are reported in Table II. Those detection limits found for this work compare well with the best previously reported detection limits for graphite furnace CSAAS.…”

Fourier-transform flame atomic absorption spectrometry with continuum source excitation

“…This affords the possibility of using the profile of the absorption line for diagnostic purposes, background correction, and for extension of the calibration curve. The capability of extending the linear range of the calibration curve has been demonstrated with continuum source AAS (26,27).…”

Continuum source atomic absorption spectrometry and detector technology: A historical perspective

“…Resonance lines for the elements Ca, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Se, Sn, V and Zn could thus be recorded simultaneously, and the calculated absorbances were all shot noise limited. Similar systems were used by several groups for many fundamental [71][72][73][74][75][76][77][78][79][80][81][82][83][84] as well as applied [85][86][87][88][89][90][91][92][93][94][95] studies, and are also described in a number of overview papers [96][97][98][99][100]. In a detailed analysis [97], O'Haver and Messman stated that the undoubted advantages, in particular flexibility and excellent background correction, were unfortunately counterbalanced by the disadvantage that for elements with resonance lines at wavelengths shorter than 250 nm LODs were significantly poorer with CS AAS than with LS AAS.…”