Heated sample cell

Abstract

Abstract A known type of heated sample cell assembly for atomic absorption spectroscopy includes an open-ended graphite sample tube having a central hole for initially introducing the sample into the tube and for allowing an inert protective gas to circulate from the otherwise closed surrounding housing into the tube to protect the interior surfaces from oxidization when the device is heated, as by large electrical currents supplied from electrodes in contact with both ends of the graphite tube. A known improvement includes the addition of holes near the ends of the graphite tube to reduce the speed at which a given total protective gas flow causes the sample to be expelled from the open end of the tube, thereby increasing useful measuring time. The present change includes providing bores through the electrodes so that the inert protective gas flows into the area immediately adjacent the open ends of the graphite sample tube. This technique of supplying additional protective gas tends to exclude air from reaching any part of the graphite tube, without causing eddy currents at the tube or complicating manufacturing of the tube by requiring carefully made additional holes in the graphite tube.

Inventors

• 👤 H Schmedes
• 👤 P Hansen
• 👤 B Welz

Bibliographic Details