HP 5890 Series I and Series II Reference Manual (05890 ... - Ipes.us

Detector Systems
Electron capture detector (ECD)
Figure 7-5
Anode
Plated 63 Ni Surface
Makeup Gas Adapter
Electron Capture Detector (ECD)
Anode Purge
Vent
Nickel Plating
Fused Silica Liner
Makeup Gas
Column
The electron capture detector (ECD) cell contains ��Ni, a radioactive
isotope emitting high•energyelectrons (�•particles).These undergo
repeated collisions with carrier gas molecules, producing about 100
secondary electrons for each initial �•particle.
Further collisions reduce energy of these electrons into the thermal
range. These low energy electrons are then captured by suitable sample
molecules, thus reducing total electron population within the cell.
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