Atsuko Adachi

Determination of vanadium in environmental samples by atomic absorption spectrophotometry

Abstract A simple and sensitive method for the determination of vanadium in water and air samples was established by using atomic absorption spectrophotometry with graphite furnace atomizer. The proposed method includes formation of a chelate complex by reacting vanadium with ammonium 1-pyrrolidine carbodithioate (APDC), extracting the chelate with xylene and measurement of the extract using atomic absorption spectrometry. The recoveries of added vanadium in various environmental samples were 98.5 and 104.4%, with a maximum coefficient variation of 9.5%. The sensitivity on this method is 10–50 times higher than previous methods. The detection limit is 0.5 μg/l.

Determination of Vanadium in Cigarettes by Atomic Absorption Spectrophotometry

In order to clarify the daily intake of vanadium, this elements levels in cigarettes were measured by an atomic absorption spectrophotometric method. In forty five different brands of cigarettes used, vanadium concentrations ranged from 0.49 to 5.33 μg/g, with a mean level of 1.83 μg/g. These were comparatively high levels compared with those in food which were below 0.79 μ g/g assayed by us. Approximately 30% of the vanadium contained in cigarette passed into the smoke. Thus dietary intake of vanadium must take smoking into account.

Adsorption and adsorption mechanism of rice bran for chloroform from tap water.

We have found that rice bran effectively adsorbed chloroform from tap water. The amount of chloroform adsorbed was plotted against the equilibrium concentration of chloroform in solution on a logarithmic scale. A linear relationship was obtained, indicating that the adsorption reaction was a Freundlich type. The removal of chloroform by rice bran was attributed to the uptake into intracellular particles called spherosomes.

Generation of cyanide ion by the reaction of phenol with nitrous acid in wastewater

It was found that phenol reacts with nitrous acid to produce cyanide ions. Cyanide ion generation is attributed to the conversion of phenol to nitrosophenol through the well-known nitrosation reaction, and decomposition of benzoquinonoxim to form cyanide and aliphatic compound.

GAS CHROMATOGRAPHIC ANALYSIS OF VEGETABLES FOR CHLOROFORM

A simple and sensitive method for the determination of chloroform in vegetables was established by using a gas chromatograph equipped with an electron capture detector. The proposed method includes solvent trapping of chloroform, and gas chromatographic separation with a detection system. The recoveries of added chloroform in various vegetable samples were 96.7 and 109.3%, within 8.6% of the coefficient variation. The detection limit is 1 μg/kg. The procedure can be used to determine chloroform at low levels in a variety of foods including mayonaise, fish, oil, and cream, as well as vegetables.

Determination of vanadium in tissues by atomic absorption spectrophotometry

Abstract A simple and sensitive method for the determination of vanadium in tissues was established by using atomic absorption spectrophotometry with graphite furnace atomisation. The proposed method includes formation of a chelate-complex by reacting vanadium with pyrrolidine dithiocarbamate (PDCA), extracting the chelate with xylene and measurement of the extract using atomic absorption spectrometry. The recoveries of added vanadium in various rat tissues were 96.7 and 109.3%, within 8.6% of the coefficient variation. The sensitivity of this method is 10 – 50 times higher than previous methods, the detection limit is 0.01 μg/g.