Penta quadrupole

Analysis All analyses were performed on a Hewlett-Packard 5985 B quadrupole gas chomatograph mass spectrometer. Plasma glucose was initially separated using the technique described above and the penta-acetate derivative of glucose was formed by adding acetic anhydride and pyridine to the dried glucose sample and heating at 100 C for five minutes. Approximately lul of the acetic anhydride solution was required for analysis. 

The Mossbauer spectrum of compound (29) shows it to contain two iron environments, and comparison of the parameters with the other data suggests that the dimeric unit contains one 5-coordinated and one 6-coordinated iron atom. The neutral monomers (31) and (32) are equivalent to the penta-coordinated monoanions with an electron removed, possibly from a ligand-based orbital. A ligand-field treatment for the temperature dependence of the quadrupole splitting in some of these complexes has been suggested [33]. 

The penta-coordinated fluoro-, acetato-, azido-, chloro-, and bromo-derivatives of haemin-type compounds show an increase in the quadrupole... 

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