Manganese monitoring

Fig. 1.9. Atmospheric pressure microwave GC-AED of organometallics. Left carbon monitored at 247.9 nm right A, chromium monitored at 267.7 nm and B, manganese monitored at 257.6 nm. (Reproduced by permission from S.A. Estes, PC. Uden, M.D. Rausch and R.M. Barnes, Journal of High Resolution Chromatography and Chromatographic Communications, 1980, 3, 471 copyright 1980 Dr. Alfred Huthig Publishers.)...

Dithiocarbamates are chemically characterized by the presence of metals in the molecule (iron, manganese, zinc, etc.) therefore, the measurement of these metals in urine has been proposed as an alternative approach to monitor exposure. For instance, increased urinary excretion of manganese has been reported in workers exposed to mancozeb (Canossa et al., 1993). Available data are at present insufficient to confirm the possibility of using metals as biomarkers of human exposure to DTC. 

Finally, NMR has also be used to study other spinels materials that do not contain manganese. For example, the intercalation/deintercalation of lithium titanate spinels such as Li4/3+Ji5/304 and Lii.i-Tii.904+a have been investigated. These materials may be used as anode materials in combination with cathodes operating at 4 V (vs Li) to produce cells with potentials of ca. 2.5 V. These materials are either diamagnetic or metallic, and unlike the mangan-ates, only very small differences in shifts are seen for Li in the different sites of the spinel structure. Nonetheless, these shift differences are enough to allow the concentrations of the different sites to be quantified and monitored following insertion of Li or as a function sample preparation method. ... 

The method described below will use the complexing reagent DTPA (diethylene-triaminepentaacetic acid) to extract, by chelation, copper, iron, manganese and zinc (including zinc on calcareous soils) it also shows promise for monitoring cadmium, nickel and lead in soils receiving sludge appli-... 

H NMR analysis was used to monitor the oxidation of dioxime 30 by manganese dioxide. Earlier work suggested that this reaction produced mainly isomer 31 <1990CHE1195>. More recent work, however, has shown that two isomeric furoxans 31 and 32 are produced in approximately equal amounts <2001RCB874>. 

There is concern that elevated environmental levels of manganese resulting, for example, from the introduction Mn-containing additives to petrol, might be associated with neurological disease. Direct EPR spectroscopy has been used to monitor Mn(II) following the addition of Mn(II) and Mn(III) complexes to human blood plasma and cell lysates.49... 

Manganese oxides As(lll) and As(V) removal by Mn02(s) is similar, up to 5 mmol As mol-1 Mn at micromolar As equilibrium solution concentrations. Freundlich isotherm obeyed. As(lll) oxidized to As(V). Rapid oxidation (minutes) and adsorption of As(lll). Monitored Mn release and effect of pH, Ca, phosphate, and sulfate Driehaus, Seith and Jekel (1995)... 

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