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The silver contents of 17 irons and steels have been determined by dropping 0.5-20mg of millings or turnings of the metals into an induction furnace situated within an atomic-absorption spectrophotometer. The limit of detection was 0.005 mug/g and the relative standard deviations were 12% or better for silver contents of not less than 0.05 mug/g. Samples are added to the furnace at 4-5 min intervals.

Results are presented for the atomic-absorption spectrophotometric determination of zinc in aluminium and aluminium-silicon alloys, and aluminium, antimony and tin in steels, by means of solid samples dropped into an induction-heated graphite-well furnace to produce the atomic vapour.

An apparatus has been constructed primarily for determination of nitrogen released from steels on reaction with organic solvent-halogen mixtures. The nitrogen is collected in a coil and then flushed with argon through a spectroanalyser that is selective to nitrogen and coupled to a recorder and integrator. The integrated signal is linearly related to the mass of nitrogen produced. The apparatus has been tested by determining the yield of nitrogen produced by reaction of hydrazine with a large excess of hypobromite in aqueous solution. For ten 57-microg amounts of hydrazine the average yield of nitrogen was 99%, with a relative standard deviation of 2.4%.

Conditions are presented for the determination of indium by atomic-absorption spectrometry following hydride generation. Indium hydride produced by addition of sodium borohydride to a solution of indium in 3M hydrochloric acid is flushed with argon into an electrically heated silica tube. The mass of indium giving 1 % absorption is 0.3 mug.

An induction-heated graphite furnace, coupled to a Unicam SP 90 atomic-absorption spectrometer, is described for the direct determination of trace elements in metals and alloys. The furnace is capable of operation at temperatures up to 2400 degrees , and has been used to obtain calibration graphs for the determination of ppm quantities of bismuth in lead-base alloys, cast irons and stainless steels, and for the determination of cadmium at the ppm level in zinc-base alloys. Milligram samples of the alloys were atomized directly. Calibration graphs for the determination of the elements in solutions were obtained for comparison. The accuracy and precision of the determination are presented and discussed.

The voltammetric oxidation of seven anthraquinones to the singly-charged radical cations has been investigated in acetonitrile and nitromethane. The voltammetric waves can be used for the quantitative determination of anthraquinones. Benzoquinones, naphthaquinones and phenanthraquinones are not oxidized in these solvents.

The voltammetric behaviour of 19 ions in 1M ammonium fluoride solution has been investigated, using a rotating platinum electrode. In this base electrolyte, manganese(II) is oxidised reversibly to manganese(IV) at + 0.52 V vs. S.C.E. and this reaction has formed the basis for a simple voltammetric method for the determination of steels and cast iron of low cobalt content.

An induction furnace coupled to a Unicam SP90 atomic-absorption spectrophotometer is described for the determination of traces of volatile elements in solutions and volatile matrices. The apparatus has been used to obtain calibration graphs for 1-20 and 50-750 ng of cadmium in microl-volumes of solution, the 228.8 and 326.2 nm resonance lines respectively being used, and to determine cadmium in 5-mg samples of zinc-base metals within the concentration range 5-400 microg g by using the less sensitive 326-2-nm line. A furnace temperature of 1,350 degrees was used. Data on accuracy and precision are presented. The apparatus could readily be used to determine trace elements in volatile materials at concentrations of 10-1000 ng/g .