base peak


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base peak

The ion in a mass spectrum with the highest measured abundance.
The relative abundance of the base peak ion is assigned a value of 100, and the abundances of all other ions plotted in that mass spectrum are normalised to that value. The y-axis in a mass spectrum is therefore given in terms of relative abundance.
References in periodicals archive ?
All the fragmentations of cellulose are present and the base peak of fragmentation appears at m/e 76 due to positive ion or free radical positive ion of CS2.
The observed base peak at M/Z 163 may be explained by the cleavage of the bond alpha to the carbonyl moiety, leading to the loss of a methoxy group.
For the DMDCS derivative of 9-hydroxyphenanthrene, the molecular ion is at the m/z value (mass-to-charge ratio) of 286, which is the base peak of the mass spectrum.
We were able to determine that the metabolite had a base peak of 270 m/z while metolachlor had a base peak of 284 m/z, suggesting O-demethylation of metolachlor leading to the formation of 2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-hydroxy-1-methylethyl)-acetamide.
The base peak may exhibit minor tailing for an active or contaminated column.
Meanwhile the last peak at m/e+ = 64 is attributing this formula C5H4 The base peak of anthranilic acid at m\e+=137 attributed to the original molecular weight.
The EI mass spectrum exhibited the molecular ion peak as a base peak at m/z 414.
The EIMS spectrum showed molecular ion peak at m/z 302 which was also observed as a base peak which is a characteristic feature of flavones.
The PD values of the linear samples and the base peaks of the coupled samples are quite low as expected for batch-produced anionic PBd.