Method and apparatus for determining the quality of a colloidal suspension
US5294891A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 18, 1993 |
| Grant date | Mar 15, 1994 |
| Priority date | — |
| Expiry date | Mar 18, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/07
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for determining the quality of a colloidal suspension. According to the method of the present invention, an oscillating input electrical signal is applied simultaneously to a sample of the colloidal suspension to be tested and to a reference solution. The reference solution is substantially identical to the colloidal suspension except that the colloidal particles have been removed. The input signal causes charge particles and molecules within both substances to move, thereby, giving rise to electrical currents. Thus, a test current is extracted from the colloidal suspension and a reference current is extracted from the reference solution. Thereafter, a differential output current is derived by substracting the reference current from the test current. The peak-to-peak magnitude of the differential output current is measured, and the phase of the output current is compared to the phase of the input signal to determine the difference in phase between the two signals. Based on the peak-to-peak value and the phase difference, the quality of the colloidal suspension is determined.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.