Nephelometric turbidity detector

Eor a dilute suspension containing roughly equal amounts of two particle sizes. Figure 20.11 shows the way turbidity changes with time at a distance, L, below the top of the liquid. Turbidity is usually expressed in terms of nephelometric turbidity units (NTu). This is in reference to a specific type of measurement technique. A nephelom-eter specifically measures the light reflected into the detector by the particles. 

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