Fresh water sample

Courtot-Coupez and Le Bihan [209,210] determined non-ionic detergents in sea- and fresh-water samples at concentrations down to 2 pg/1 ppm by benzene extraction of the tetrathiocyanatocobaltate (II) (NH4)2 (Co(SCN)4) [ 182] detergent ion-pair, followed by atomic absorption spectrophotometric determination of cobalt [209]. 

Yokoi, K., Yamaguchi, A., Mizumachi, M. and Koide, T. (1995) Direct determination of trace concentrations of lead in fresh water samples by adsorptive cathodic stripping voltammetry of a lead-Calcein Blue complex. Anal. Chim. Acta, 316, 363-369. 

Boyle et al. [47] have described a method for determining cobalt in non saline waters using cation exchange liquid chromatography. Cobalt was determined directly in 500pL fresh water samples with a detection limit of 20pM per kg. 

Fig. 12.8 Chlorine-36 as a function of chlorine for the Lachlan case study. The intake line is based on the fresh water samples from location A (Fig. 12.7). All the data points, except one, lie on or beneath the local intake line, indicating ages on the order of one half-life, that is, about 300,000 years (see text). The single point above the intake line may indicate contributions of bomb 36C1.

Sample matrix the general nature of the sample and its components that can have a significant impact on the performance of an analytical method. For example, sea water and fresh water sample matrices are significantly different and this difference can affect the performance of an analytical method. 

Recent studies show that alkylphenols alone can largely account for the estrogenic activity seen in fresh water samples (Rutishauser et al., 2004 Cespedes et al., 2005 Quiros et al., 2005). However, unpublished data from the authors laboratory show that natural estrogens (in this case Estriol and Estrone) can be found in natural samples at... 

Ultrasonic nebulization This has been applied since the early work on ICP-AES [151], Both nebulizer types where the sample liquid flows over the nebulizer transducer crystal and types where the ultrasonic radiation (at 1 MHz frequency) is focussed through a membrane on the standing sample solution have been used. When applying aerosol desolvation the power of detection of ICP-AES can be improved by a factor of 10 by using ultrasonic nebulization. This specifically applies to elements such as As, Cd and Pb, which are of environmental interest. However, because of the limitations discussed in Section 3.2, the approach is of particular use in the case of dilute analytes such as in water analysis [150]. Additional fine detailed development, however, is regularly carried out, as with ICP-AES the process is crucial for elements such as Cd, As and Pb for which threshold values in fresh water samples can just still be measured reliably with this type of sample introduction. Such a development is the microultrasonic nebulizer (pUSN) operated with argon carrier gas, as described by Tarr et al. [410]. 

A. Schmitt, L. Buttle, R. Uglow, K. Williams, S. Haswell, An integrated reduction method for the determination of urea as ammonia in fresh water samples, Anal. Chim. Acta 284 (1993) 249. 

Kawakubo, S., Naito, A., Fujihara, A. and Iwatsuki, M. (2004) Field determination of trace iron in fresh water samples by visual and spectrophotometric methods. Anal Sci, 20 (8), 1159-1163. 

Results of enrichment cultures (I - V) from fresh water samples after 15-20 volume changes in the chemostat under dual substrate limitation of thiosulfate (t) and actetate (a) at a dilution rate of 0.05 h , using different mixtures of t + a. Adapted from Gottschal and Kuenen, (IJ). 

Chromium(VI) was determined in fresh water samples using solid phase absorptiometry. The complex of chromium(VI) with 1,5-diphenylcafbazide was sorbed on a cation exchanger packed in a flow-cell. The detection limit was as low as 33 ng 1 [12]. 

Henze G, Wagner W, Sander S (1997) Speciation of arsenic(V) and arsenic(III) by cathodic stripping voltammetry in fresh water samples. Fresen J Anal Chem 358 741... 

Low levels of bromide ions could be determined in fresh water samples by the method described by Lundstrom et al. [71]. In the first step, the bromide ion content of the slightly acidified sample is preconcentrated on an anion-exchange resin. Next, it is eluted with 2 M NaC104 and the bromide content is oxidized to BrOs" with persulfate, which is determined spectrophotometrically. The detection limit of this method is 1.5 nM and the lower limit of determination is 5 nM. 

Bings N. H., Steeanka Z. and Mallada S. R. (2003) Flow injection electrochemical hydride generation inductively coupled plasma time-of flight mass spectrometry for the simultaneous determination of hydride-forming elements and its application to the analysis of fresh water samples. Anal. Chim. Acta 479 203-214. 

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