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Development Of A Portable Carbon Monoxide Sensor Based On An External Cavity Diode Laser At 1565 Nm, Eva Shirley Norris

Theses

Carbon monoxide is a major trace gas pollutant with road traffic being responsible for most emissions. Work has been done on the development of a carbon monoxide sensor, which is potentially capable of measuring the gas in vehicle exhaust emissions. This is based on tunable diode laser absorption spectroscopy The device must distinguish carbon monoxide from other gas species and from particulate matter. The device should also operate with a response time of the order of one second, have the potential for portability and a capacity for remote operation. Experimental work presented compares and contrasts the characteristics of the free-running …

Trace Analysis Of Organic Substances, Alan Giltinan

Theses

One of the major challenges facing the pharmaceutical industry is the control of the amount of trace contaminants during the manufacture of organic substances. Lowering the level of contamination improves the quality of the product and reduces possible side effects.

One of the main techniques used to detect trace contaminants is UV-VIS spectroscopy, where the unique absorption fingerprint of a chemical reveals its presence. UV-VIS absorption is based upon the Beer-Lambert Law. The critical point to note about this law is that the absorption is exponentially dependent on both the concentration of the absorber and the pathlength traversed by the …