Thin-layer Design

There are two popular designs for the flow cells, a thin-layer design and a wall-jet design, both shown in Fig. 15. The potentiostats are generally of the... 

Fig. 15 Amperopetric electrochemical detector cells (a) thin-layer design (b) wall-jet design. Legend (1) inlet from column (2) working electrode (3) cell block (4) passage to reference electrode (5) to counter electrode.

Taking into account the general considerations outlined above the spectroelec-trochemical cell has to be of a thin layer design. A typical example is shown in a cross section in Fig. 5.48 another view is presented in Fig. 5.49, showing major features of the cell. In cases where a standard spectrometer is used, the cell has to be mounted in the optical beam using an external reflection attachment as schematically depicted in Fig. 5.47. 

Mu and Kadish have described an ECESR cell with a thin layer design suitable for measurements at both ambient and low temperatures [617]. The thin layer of electrolyte solution is enclosed by the quartz tube inserted into the microwave cavity of the ESR spectrometer and a solid quartz rod fixed in the center of the tube. An expanded platinum mesh in the gap is used as the working electrode. At low electrode potential scan rates, the cell shows an acceptable electrochemical response. 

The great advantage of the thin-layer design is that the small volume of analyte within the layer is... 

In units designed to use a precoat filter aid, the dmm can be evacuated over the fiiU 360° and fitted with an advancing knife system that continuously shaves off the deposited soHds together with a thin layer of the precoat. The precoat has to be renewed periodically. 

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