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A quality index for reference mass spectra

✍ Scribed by David D. Speck; Rengachari Venkataraghavan; Fred W. McLafferty

Publisher
John Wiley and Sons
Year
1978
Tongue
English
Weight
482 KB
Volume
13
Category
Article
ISSN
1076-5174

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✦ Synopsis

A numerical rating for evaluating the qnality of reference maw spectra used for retrieval and interpretive applications is proposed. The overall quality index is the product of seven quality factors: (1) 8oorce of the spectrum; (2) ionization conditions; (3) higher m o l e d u weight impurities; (4) illogical neutral losses; (5) isotopic abundance accuracy; (6) number of peab, and (7) lower ma88 limit of peaks. For quality factor 6 the number of peaks of abundances ~1 9 :

was found to correspond to 15 more than the namber of atoms in the molecule with a correlation coefficient of 0.482. The program has been found osehl in preparing a data base of 41429 1111158 epectra; for the majority of spectra judged to be unsalisfactory by the program this arose from a low quality factor 6 value (too few peaks).

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