Perchlorate in Sea Water

Author(s):  
R. Greenhalgh ◽  
J. P. Riley

The use of tetraphenylarsonium chloride for the detection and determination of perchlorate in sea water has been investigated. An aqueous solution of this reagent gives a visible precipitate of tetraphenylarsonium perchlorate with sea water containing 5 μg ClO4-/ml. within 10 min. For the quantitative determination of traces of perchlorate, potassium perrhenate is added to the water sample, and the tetraphenylarsonium perrhenate, which is precipitated by addition of the reagent, co-precipitates tetraphenylarsonium perchlorate. Perchlorate is determined in the mixed precipitate by infra-red absorption spectrophotometry. Using 100 ml. of sea water, a sensitivity of 0·03 μg ClO4-/ml. can be attained, with a coefficient of variation of ca. 10%. No interference is caused by the ions normally present in sea water.

1973 ◽  
Vol 19 (5) ◽  
pp. 492-495 ◽  
Author(s):  
M A Evenson ◽  
Susan Koellner

Abstract Rapid, accurate, and precise gas-chromatographic methods are reported for measurement of propoxyphene ("Darvon") in serum. A sample of 5 ml of serum is required for quantitation in blood after a therapeutic dose of 130-195 mg of propoxyphene; in cases of overdose of propoxyphene, only 1 ml of serum is required in a "toxic method" variation. Neither serum from healthy controls or from hospitalized patients contains interfering substances. Several commonly used analgesic and sedative drugs, added to a serum pool, also did not interfere. Day-to-day precision of the therapeutic method, as measured by the coefficient of variation (CV), is 7%; the CV for the method as applied to overdose cases is less than 3%. Propoxyphene added to serum could be about 86% accounted for analytically.


1965 ◽  
Vol 48 (4) ◽  
pp. 771-774
Author(s):  
D P Johnson ◽  
H A Stansbury

Abstract A method has been developed for detecting residues of carbaryl (1-naphthyl methylcarbamate) as well as its hydrolysis product, 1-naphthol, in dead bees. The method is based on extraction of the bees with benzene, followed by a cleanup involving liquid partitioning and chromatography on Florisil. The quantitative determination involves hydrolysis of carbaryl to 1-naphthol and coupling of the latter with p-nitrobenzenediazonium fluoborate in acetic acid to form a yellow substance. For separate analysis, free 1-naphthol is separated from methylene chloride into a basic aqueous solution. The sensitivity of the method is about 0.1 ppm; recoveries averaged 85.6 ± 6.6% for 1- naphthol and 83.8 ± 2.7% for carbaryl.


1993 ◽  
Vol 47 (6) ◽  
pp. 764-772 ◽  
Author(s):  
Irvin M. Citron ◽  
Patrick M. Hanlon ◽  
Stephen Arthur

This investigation has resulted in an analytical method for the quantitative determination of total lanthanide concentration in aqueous solution by absorbance at 240 nm in the ultraviolet followed by quantitative determination of individual lanthanide ion concentrations by the use of concentration-responsive absorption peaks in the 190–235 nm region. The 240-nm peak is present and is proportional to concentration regardless of the ligand employed to complex the lanthanides (including H2O). The individual lanthanide/ligand peaks in the 190–235 nm region were selected on the basis of their separation from one another, their linearity of absorbance vs. concentration, and their statistical reliability based on replicate sample analyses. Lanthanides involved in this investigation were La+3, Nd+3, Eu+3, Ho+3, and Yb+3. Ligands ultimately selected for complexation were citrate for La+3, Nd+3, and Ho+3, and DTPA for Eu+3, Ho+3, and Yb+3. When large amounts of heavy metal ions were present, a modified method was developed with citrate as the only complexing ligand for all five lanthanides. The method here developed permits the analyses of lanthanide ions in aqueous solution without prior separation and involves the use of comparatively inexpensive instrumentation (UV absorption spectrophotometer).


The Analyst ◽  
1986 ◽  
Vol 111 (5) ◽  
pp. 539 ◽  
Author(s):  
Heather J. Bowley ◽  
Elizabeth A. Crathorne ◽  
Donald L. Gerrard

1969 ◽  
Vol 37 (286) ◽  
pp. 256-261 ◽  
Author(s):  
J. W. Aucott ◽  
M. Marshall

SummaryTwo methods using nujol and hexachloro-butadiene mulls are described to analyse the water content of powdered granite samples. The nujol mull analyses were carried out on a Unicam SP 100 spectrometer using the silica content of the rock as an internal standard. The hexachlorobutadiene mull analyses were done by a twin-path Unicam SP 200 spectrometer, using hexachlorobutadiene as the internal standard. The broader and more pronounced V1 vibrational mode (3450 cm−1) is ratioed to a standard of known composition. Comparisons are also made between absorption due to free water (V1 = 3450 cm−1) and combined water (V3 = 3680 cm−1) in aplites, biotite granite, and chlorite schists.


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