Atomic absorption procedure

Olafsson [427] has described a semiautomated determination of manganese in seawater using leucomalachite green. The autoanalyser had a 620 nm interference filter and 50 minute flow cells. Findings indicated initial poor precision was related to pFl, temperature, and time variations. With strict controls on sample acidity and reaction conditions, the semiautomated method had high precision, at least as good as that achieved by preconcentration and atomic absorption procedures, and provided precise, rapid, shipboard information... 

The permanganate solutions obtained from both the coal and ash samples were analyzed by the direct aeration flameless atomic absorption procedure. The concentration in each sample was calculated from the measured mercury value, the blank concentration in the permanganate solutions, and the weight of the samples. 

Earlier atomic absorption methods [164-167] from the determination of molybdenum in soils employed a preliminary solvent extraction step to improve sensitivity in view of the low concentrations of molybdenum occurring in most soils. Baucells et al. [5] developed a graphite furnace atomic absorption procedure which was capable of determining down to 8.4 pg of molybdenum in a soil matrix solution with a precision of 4% for 100 pg/1 molybdenum. These workers showed that a char temperature of 1500 °C and an atomisation tem-... 

The determination of dimethylselenides and diethylselenide in scrubbed air samples has been discussed [699], This method is based on a gas chromatographic-atomic absorption procedure and could, no doubt, be adapted for the analysis of waters. 

An alternative to preparing standardized carriers is to purchase certified standards for other analytical methods. For example, standards for atomic absorption procedures have a concentration of 1,000 ppm (mg/L) and could be pipetted in 10-ml aliquots. This choice is suitable if the laboratory analyzes a large number of samples and a certificate is required for the standard solution. 

There were several observations made concerning the arsenic analysis by both the AgDDC technique and the high-sensitivity atomic absorption procedure during the course of this investigation. Turbidity problems were initially encountered in the AgDDC colorimetric procedure. 

In the atomic absorption procedure 5-10 mg of organoantimony compound is dissolved in 5 ml of butan-2-one, acetone, dimethoxyethane or THF depending on the solubility of the organoantimony compound. Concentrated hydrochloric acid and ethanol are added and the mixture diluted with water. The solution is aspirated into a fuel-rich air-hydrogen or air-acetylene flame and the absorbance measured at 217.6 nm in the flame just above the burner head. The calibration graph is slightly curved over the range... 

Volatile organics, either naturally occurring or sampler-induced, may interfere with adsorption at the mercury wavelength (2537 A) during the usual flameless atomic absorption procedure (4). 

Vinas et al. (1993a), determined copper in biscuits and bread using a fast-program slurry electrothermal atomic absorption procedure and Miller-Ihli (1988) also used EAAS after slurry preparation for simultaneous multi-element AAS, as did Littlejohn et al. (1985) who introduced slurried food samples into the graphite furnace for analysis. Haswell and Barclay (1992), carried out on-line microwave digestion of slurry samples with direct flame atomic absorption spectrometric elemental detection. 

ViNAS P, Campillo N, Gaecia IL and Coedoba MH (1993a) Analysis of copper in biscuits and bread using a fast-program slurry electrothermal atomic absorption procedure. J Agric Food Chem 41 2024-2127. 

The results of this investigation show that the method described can be effectively used when the concentration of metals in water is too low for analysis by normal atomic absorption procedures provided the metals form solvent extractable complexes with sodium diethyldithiocarbamate. We use this method routinely for the determination of iron, lead. 

El. Ediger, R. D., and Goleman, R. L., A modified Delves cup atomic absorption procedure for the determination of lead in blood. At. Absorption Newslett. 11, 33-36 (1972). 

A sensitive method is therefore required. As a general rule atomic-absorption procedures and spectrophotometric methods may be employed. 

In comparison with the spectrophotometric method the atomic-absorption procedures are simpler, faster and virtually free of interference. Where no atomic-absorption spectrophotometer is available, sufficiently accurate and reliable results can be obtained with the dithizone spectrophotometric method. 

Persson, J.A., Freeh, W. (1980) Investigations of reactions involved in electro-thermal atomic absorption procedures part 8. A theoretical and experimental study of factors influencing the determination of phosphorus. Anal. Chim. Acta, 119, 75. 

Despite their advantages, it is unlikely that emission methods based on high-energy sources will ever completely displace flame and electrothermal atomic absorption procedures. In fact, atomic emission and absorption methods are complementary. Among the advantages of atomic absorption procedures are simpler and less expensive equipment requirements, lower operating costs, somewhat greater precision (presently, at least), and procedures that require less operator skill to yield satisfactory results. ... 

Cappon and Crispin Smith O evaluated the accuracy and precision of the method by analyzing different sample types fortified with mercuric chloride and methylmercuric chloride (Table 20). Mean deviation and relative accuracy averaging 3.2 and 2,2% respectively, were observed. They also cross checked results obtained by their method and by an atomic absorption procedure. Results obtained on samples by both methods are given in Table 21, There is good agreement between the two methods for samples methyl-, ethyl-, and inorganic mercury, and this is expressed in terms of GC/AA ratios. 

In addition to traces of metals due to catalyst remnants, metal containing processing chemicals and adventicious impurities, polymers might also contain higher concentrations of metals. Examples of this include metallic stearate heat stabilizers in PVC and fire retardant additives such as antimony trioxide in acrylics and polyolefins. Such elements can be determined by atomic absorption procedures such as that described in Method 71. 

Dolcourt, ]., Hamrick, H., OTuama, L., Wooten, J. and Baker, E.L. (1978) Increased lead burden in children of battery workers. Pediatrics, 62, 563-571 Ediger, R.D. and Coleman, R.L. (1972) Modified Delves cup atomic absorption procedure for determination of lead in blood. Atomic Absorpting Newsletter, 11, 33 Elardo, R., Bradley, R. and Caldwell, B.M. (1975) The relation of infants home environments to mental test performance from six to thirty-six months a longitudinal analysis. Child Dev., 46, 71-76... 

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