Apparatus to investigate the properties of a fluid and process for investigation of sample of microorganisms or other biological material suspended in a fluid

摘要

Apparatus for determining the density and thus concentration of a suspension of microorgansims, comprises an electrically conducting pipe through which the sample passes. Using an induction coil and with an applied magnetic field, currents are induced in the pipe leading to mechanical vibration. Acoustic waves pass through the sample and are detected by essentially the reverse process. By sweeping frequency and detecting resonances, high accuracy can be achieved.