Studies in Mass Spectroscopy. Part XI. Mass Spectra of 1,4-Dicarbonyl Compounds.

POSITIVE AND NEGATIVE ION MASS SPECTRA OF RING - SUBSTITUTED NITROBENZENES

The 70 ev positive and negative ion mass spectra of ring-substituted nitrobenzenes were studied. The influence of the substituent group on the fragmentation modes of the molecular ions is discussed. The effect of pressure in the formation of negative ions was also studied. As expected, the ratio of fragment ions to negative molecular ions decreased with increasing pressure in ion source.

Mass Spectra of Some Organa-Lead and Organa-Mercury Compounds

:\<Iass spectra of letramethyl and tetraethyl lead and of dimethyl, diet llyl, and di-n-butyl mercury were obtained with a Co nsolidated 21102 mass spec trometer. Monoisotopic spectra were calculated by using the isotopic abundance derived from eac h spectrum. A variation in the lead isotope abundance was observed in the commercially available lead a lkyls. No variation was observed a mong t he...

Modelling CDA mass spectra

We present the initial results from a simulation of ion behaviour within Cassini’s cosmic dust analyser (CDA) instrument, using an inhouse ion dynamics code. This work is to enable and enhance the detailed interpretation of dust impact ionisation mass spectra returned from the Saturnian system. Early work has already provided insights into the properties of the impact plasma in both lowand high...

accurate-mass spectra

Gas Chromatography-Mass Spectroscopy

Gas chromatography-mass spectroscopy (GC-MS) is one of the so-called hyphenated analytical techniques. As the name implies, it is actually two techniques that are combined to form a single method of analyzing mixtures of chemicals. Gas chromatography separates the components of a mixture and mass spectroscopy characterizes each of the components individually. By combining the two techniques, an...