V O L U M E 2 3, NO. 5, MAY
25A
1951
Coleman Nepho-Colorimeter FOR
THE
EXACT
MEASUREMENT
OF
COLOR, HAZE
FOR NEPHELOMETRY Nephelometry is the science of evaluating haze in liquids by measuring its ability to reflect light, this ability being directly related to the concentration of the suspended phase. The Model 9 Nepho-Colorimetet is an extremely sensitive and highly precise instrument for measuring this reflected (Tyndall) light. Coleman Certified Nephelos Standards permit expression of such measurements in terms of a fixed, numerical scale. Data thus becomes universally significant and comparable. Repeated preparation of temporary standards is eliminated. The linear relation between instrument response and Tyndall light intensity makes Nephelos/ Concentration calibrations simple and exact. Nephelometry is finding increasing application in the examination of Biologicals, Bacterial Suspensions, Industrial Waters, Beverages and Blood Sera. FOR C O L O R I M E T R Y Actuation of a single switch converts the Model 9 Nepho-Colorimeter from a nephelometer to a precision colorimeter capable of colorimetric measurements of a precision and certainty far
AND
TURBIDITY
IN
LIQUIDS
above that ordinarily available in filter instruments. Selected filters cover the visible spectrum in six uniform increments. Scratch-proof mountings assure continued uniformity. Directreading scales for optical density or percent transmittance readings may be interchanged with scales individually calibrated for specific analytical methods. Interchangeable adapters accept cuvettes ranging from 25mm depth down to capillaries requiring only 0.01ml of solution. FOR T U R B I D I M E T R Y When the particles in a liquid suspension are sufficiently concentrated to interfere substantially with the transmission of light, the amount of suspended material may be measured by determining the transmittance of the suspension and relating it to particle concentration. Turbidity measurements with the Model 9 NephoColorimeter are characterized by the ease and speed of directdeflection reading and by the unparalleled precision available from the calibrated potentiometer. Determinations can be made with either white light or colored light.
Write f o r Bulletin A B - 2 1 5 f o r f u l l details.
Coleman Photo-Nephelometer(MODEL 7) For Nephelometty only. The Model 7 Photo-Nephelometer is capable of the same precision in nephelometric measurements as the Model 9 Nepho-Colorimeter but is not equipped for Colorimetric or Turbidimetric measurements by transmitted light. Write f o r Bulletin A B - 2 1 3 f o r f u l l i n f o r m a t i o n .
COLEMAN INSTRUMENTS 318 MADISON ST. MAYWOOD,ILLINOIS
