Atomic mass spectrometiy

The use of soft ionization techniques in mass spectrometiy such as fast atom bombardment (FAB) has grown considerably the last few years, due to its abihty to ionize complex organic molecules not amenable to more conventional mass spectrometric methods (El,Cl). 

Mass spectrometiy (MS) is a powerful tool for identifying compounds that are related. Coupled to an LC system, mass spectrometry can often detect the similarities and relatedness of materials corresponding to chromatographic peaks by their characteristic fragmentation pattern and/or by the fact that they contain particular atoms, e.g.. Cl and Br, that have characteristic isotope ratios. More simply, it may just be that two compounds have a similar molecular weight or molecular weights separated by expected or explicable differences ... 

For atoms other than carbon, hydrogen, oxygen, and nitrogen, it is necessary to calculate the expected intensities of the M + 1 and M+2 peaks for a partieular moleeular formula. You must establish the presence of these other elements by means other than mass spectrometiy. 

Barber, M., Bordoli, R. S., Elliott, G. J., Sedgewick, R. D., and Tyler, A. N., Fast atom bombardment mass spectrometiy. Anal. Chem., 54, 645A, 1982. 

Second-generation reference material refers to the serum preparation of Versieck et al. [49]. ID-MS, isotope dilution-mass spectrometiy NAA, neutron activation analysis FAAS, flame atomic absorption spectrometry ETAAS, electrothermal atomic absorption spectrometiy. 

The only characterization data for La Cg2 was Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometiy data, which did not provide unambiguous evidence that the La atom was actually encapsulated in the fiiUerene. The unambiguous characterization of an endohedral fiillerenes was achieved in 1995, using synchrotron X-ray diffraction maximum entropy method (XRD-MEM)-Rietveld method to provide physical details about the structure of Y Cg2. Interestingly, the Y atom is not located in the center... 

Over the past years a number of small silicon-containing ions have been structurally characterized by collisional-activation mass spectrometiy. These ions have been used as precursors for the generation of their neutral counterparts via Neutralization-Reionization Mass Spectrometry (NRMS) . To a large extent the interest in small elusive silicon-containing molecules is due to the role which these species have been postulated to play as intermediates and building blocks in the genesis of interstellar matter" . In particular, the different conceivable pathways which lead from atomic silicon cations to the formation of neutral silicon-containing molecules have been studied intensely" A second... 

J. H. Analysis of Rntbeninm Carbonyl-Porphyrin Completes a Comparison of Matrix-Assisted Lase- Desorption/Ioni-zation Time-of-Flight, Fast-Atom Bombardment and Held Desorption Mass Spectrometiy. Eur. Mass. Spectrom. 1997,3,427 38. 

Abstract Analyses of cadmiutn concentratiOTis in biological material are performed using inductively coupled plasma mass spectrometry (ICP-MS) and atomic absorption spectrometiy (AAS), but also electrochemical methods, neutron activation... 

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