Device for measuring concn. of soln. or suspension - heated probe is placed in pipe through which soln. is circulated, and concn. is derived from temp. difference between soln. and probe

摘要

The procedure comprises placing an electronically heated probe in the soln. or suspension, the temp. of the probe and the temp. difference between the probe and the soln. or suspension are measured, and the concn. of the soln. or suspension is calculated from the above measurements. The heating current applied to the probe is held constant during measurement, and the probe is inserted in a tube through which the soln. or suspension is circulated by a pump at a velocity in the range 0.01 and 1.0 metres per second. Measurements may be made at a number of different fluid velocities, greatest accuracy usually being achieved at lower velocities. USE/ADVANTAGE - Used in the food industries for the measurement of the concn. of microorganisms or their prods. in solns. or suspensions. The disadvantages of existing optical, reactive and electrochemical measurement methods, which are esp. due to the adherence of the microorganisms to the probes used and to the presence of gas bubbles in the soln. or suspension, are overcome by a method which is simple to operate and requires no complicated instrumentation.