An instrument has been developed to determine the viscosity of liquid samples. It is in effect a modified Ostwald viscometer. A sample aliquot is injected into a carrier stream of similar viscosity to the sample, flowing along a tube of 0.086cm i.d. The passage of the sample is detected at a suitable point down stream and the viscosity of the sample may be determined from the sample velocity or alternatively under "Taylorian" conditions of slow flow rates, a relationship between peak height and (t/+i)9s has been found to exist. Chemical interaction between the sample and carrier, most probably in the form of hydrogen bonding has been found to cause deviations from linearity whereas in systems where no interaction can occur linear relationships have been found to exist for both relationships. The use of calibration curves based on standards of similar composition to the unknown sample should take into account any anomolies occuring in the system, thus enabling the viscosity of the sample to be determined. The instrument is microcomputer controlled, this includes the sample injection, maintenance of a constant temperature throughout the whole flow system via a thermostated water bath and water jacket housing thermistors which relay the temperature to the microcomputer, data collection from the detectors, processing and displaying results to the user, and balancing detector circuits. Two microcomputers have been used, MOUSE developed at AERE, Harwell, and a Commodore 32K PET. The MOUSE collects all the data prior to transmitting it to the PET for the data processing. This distributed computing approach has ensured rapid data collection and ability to perform complicated data processing routines on the data. Precisions of 0.2 to 0.3% have been obtained for selected systems, when the sample volume is 3071 and the time of determination 10-20 sec. In addition the thesis is concerned with automating FIA by microcomputer; several measurements of diffusion coefficents have been made by this method.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:637064 |
| Date | January 1982 |
| Creators | Goad, T. B. |
| Publisher | Swansea University |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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