The sample chamber is an open quartz tube with two gas ports.
The inner diameter of the gas ports is 4 mm. There are two
carrier gas streams. One gas stream passes through the sample
chamber and carries the laser-ablated mass out of the chamber
and into the ICP. The second gas stream does not enter the
chamber but is combined with the first stream at the exit of the
chamber via a T-joint (Figure 1). The flow rates of both gases
were 0.5 L/min; i.e., the combined central-channel gas flow rate
was 1 L/min. The first stream of carrier gas that passes through
the sample chamber is called “chamber gas”; the second stream
is called “makeup gas”..