Large-volume samples analysis

Thorinm-232 is the only non-radiogenic thorium isotope of the U/Th decay series. Thorinm-232 enters the ocean by continental weathering and is mostly in the particulate form. Early measurements of Th were by alpha-spectrometry and required large volume samples ca. 1000 T). Not only did this make sample collection difficult, but the signal-to-noise ratio was often low and uncertain. With the development of a neutron activation analysis " and amass spectrometry method " the quality of the data greatly improved, and the required volume for mass spectrometry was reduced to less than a liter. Surface ocean waters typically have elevated concentrations of dissolved and particulate 17,3 7,62... 

Huang, H.Y. et al.. Analysis of food colorants by capillary electrophoresis with large-volume sample stacking, J. Chromatogr. A, 995, 29, 2003. 

He Y. and Lee H.K., Large-volume sample stacking in acidic buffer for analysis of small organic and inorganic anions by capillary electrophoresis, Anal. Chem. 71, 995, 1999. 

An Evaluation of the Preparation of Resin Samplers for Broad Spectrum Analysis of Large-Volume Samples... 

Low-volume sampling is typically used for quantitative analysis for specific compounds, such as pesticides, polychlorobiphenyls (PCBs), and organic acids. Large-volume sampling is used to simultaneously... 

Scott, B.F., C.A. Moody, C. Spencer, et al. 2006. Analysis for perfluorocarboxylic acids/anions in surface waters and precipitation using GC-MS and analysis of PFOA from large-volume samples. Environ. Sci. Technol. 40 6405-6410. 

Powell, M. J., and Timpermann, A. T. (2005). Quantitative analysis of protein recovery from dilute, large volume samples by tangential flow ultrafiltration. J. Memb. Sci. 252(1-2), 227-236. 

Due to nanoliter per minute flows of CE the concentration-based detection limits are seriously degraded in comparison with those obtained by LC, limiting the application of CE in Cd speciation analysis of real samples. In any case, there are CE strategies (e.g., large volume sample stacking) that are able to preconcentrate the analytes and have been successfully applied to real samples in order to improve the detectability of Cd species in MTs by CE-ICP-MS. Figure 2 shows typical electrophoretic results by a hybrid technique for speciation of Cd-MTs in fish samples of environmental monitoring interest. 

Fig. 36.10 Schematic diagrams of the dynamic pH junction-sweeping strategy. Steps (a) large-volume sample injection, (b) begiiming of pH junction sweeping, (c) end of pH junction weeping, and (d) normal MEKC separation (Modified fi om ref. [131]). The analysis is performed on four pyrrolizidine alkaloids whose pKas were in the range 5.44-6.65...

S. Usenko, K.J. Hageman, D.W. Schmedding, G.R. Wilson, and S.L. Simonich. Trace analysis of semivolatile organic compounds in large volume samples of snow, lake water, and ground-water. Environ. Sci. Technol., 39(16) 6006-6015, 2005. 

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