INDEX stream tube

Figure 9. Refractive index signals obtained when 150 gL of distilled water is injected into a seawater carrier stream (a). The postinjector column was 90 cm of 0.8-mm ID tubing. On the abscissa, 100% corresponds to seawater with a salinity of 33.3 ppt and 0% corresponds to distilled water. The seawater was diluted by volume to produce the intermediate solutions. The peak-to-peak signal is also plotted (b).

In segmented flow analysis, axial sample dispersion is not pronounced, being influenced mainly by the characteristics of the thin liquid film established at the tubing inner wall and by the number of segments per sample (see 5.1.2). Reduction in sample concentration is therefore strongly dependent on the addition of confluent streams. Hence, the flow rates of the sample/wash and confluent streams are the main parameters determining sample dispersion, and application of Eqs 3.10 and 3.13 can then make this practical index readily available. 

Fig. 3.41 Schematic pattern of the oxygen index apparatus 1 heat-resistant glass tube 2 gas stream distributor 3 wire gauze 4 specimen 5 control valve and gauge for gas stream 6 gas burner ...

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