| 摘要 |
<p>A method is described of tracing the movement of particles conveyed by a fluid medium by determining selected properties of the particles to be traced, selecting or forming tracer particles the corresponding properties of which are substantially similar and having the property that they emit or can be stimulated to emit electromagnetic radiation within a limited range of wavelengths. A quantity of the tracer particles is introduced into the fluid medium and the intensity of electromagnetic radiation within the said limited range from a sample of the fluid medium at or taken from a detection location remote from that at which the tracer particles were introduced is detected. Apparatus for performing the method in situ at the site from which samples are taken is also described.</p> |
