Table 4 Experimental empirical formula for calculating plasma electron density based on the concentrations of the contaminant elements.

From: Calibration-free picosecond LIPS for quantifying heavy metals in soils near Egyptian industrial sites

Element

Ne (cm−3), C (ppm)

S1

S2

Cd

Ne = (1.317 + (348.8 × 10−5 × C)) × 1016

Ne = (− 1.067 + (1944.3 × 10−5 × C)) × 1016

Fe

Ne = (1.566 + (0.0 × C)) × 1016

Ne = (− 8.048 + (15488.0 × 10−5 × C)) × 1016

Zn

Ne = (− 1.631 + (2318.3 × 10−5 × C)) × 1016

Ne = (1.190 + (632.0 × 10−5 × C)) × 1016

Ni

Ne = (1.563 + (0.0  ×  C)) × 1016

Ne = (0.429 + (240.0 × 10−5 × C)) × 1016

Back to article page