Background equivalent concentration

Besides these data, background equivalent concentrations (BEC) are presented for the adjustment of the dynamic bandpass tuning parameters. 

In trace analyses, the slope of the analytical evaluation curve (in logarithmic form) is usually I at higher concentrations ij may be > 1 as a result of self-reversal. In trace analysis by AES, the intensity of the spectral background /u can be used as reference signal and cr should be replaced by Cu the concentration at which the line and background intensities are equal (background equivalent concentration or BEC value) ... 

BEC An abbreviation for background equivalent concentration, by-product ions Ionic species formed as a result of secondary reactions that take place in a reaction/collision cell. Also refer to secondary (side) reactions. 

Another figure of merit that is being used more routinely nowadays is background equivalent concentration (EEC). EEC is defined as the intensity of the background at the analyte mass, expressed as an apparent concentration and is typically calculated in the following manner ... 

Chemical ionization by Ar+ in the ion trap (of H2O, O2, N2, pump oil, etc.) can produce background at nearly every elemental m/z. The intensity of the chemical ionization background spectrum in PNNL s early ion trap work was in the range <0.005 to 1 ppb BEC (background equivalent concentration) as shown by a comparison of the mass spectra in Figure 2.38. The background is nearly eliminated if the low mass cut-off of the ion trap is set above m/z 40 during... 

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