Rotating arm collector

This paper is a summary of our findings from a four-year study of the chemical composition of fog and cloud water in California. Fog water was sampled at a number of sites with a rotating arm collector, which was developed in our laboratory and collects representative samples. Field investigations in the Los Angeles basin, the San Gabriel Mountains, and the San Joaquin Valley revealed very high ionic... 

Figure 17. Collection efficiency of model collector (i.e., a scaled-down version of the Caltech rotating arm collector) vs. generalized Stokes number. Predicted (----------) Experimental (H-— ).

A screen collector (lower size cut 2 microns, sampling rate 20 m min ) was designed (68) and has been used in the field. Side-by-side comparison indicates that samples collected with this collector and with the rotating arm have similar concentrations. 

The Faraday collector F is supported on chromel arms to which molybdenum points are attached for pivots. A small nickel rod, at the lower end of a 1-mm molybdenum wire attached to the lower chromel arm, serves as a magnetic control for rotation of the collector about an axis which lies in the face of the crystal and intersects the incident beam at an angle of 90°. 

As the flow spreads out into the rim, the solids are deposited or settled along the way. At the bottom is shown a squeegee mounted on a collector arm. This arm is slowly rotated by a motor as indicated by the label Drive. As the arm rotates, the squeegee collects the deposited solids or sludge into a central sump in the tank. This sludge is then bled off by a sludge draw-off mechanism. 

Polymerisation stations 7 Six arm rotating structure to support mould carriers 8 Central collector of signals, air and warm water 9 Supporting structure (and rotoi not shown)... 

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