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Estimation of vanadyl porphyrin concentration in sedimentary kerogens and asphaltenes
(Fuel, 2000)
We describe a new, rapid method for determining the concentration of vanadyl porphyrins (VO2+-P) associated with the kerogen of bituminous sedimentary rocks using electron spin resonance (ESR). The method is simple, ...
Air oxidation of the kerogen/asphaltene vanadyl porphyrins: an electron spin resonance study
(Journal of the Serbian Chemical Society, 2000)
The thermal behavior of vanadyl porphyrins was studied by electron spin resonance during heating of kerogens, isolated from the La Luna (Venezuela) anti Serpiano (Switzerland) bituminous rocks, at 250 degrees C for 1 to ...
Copper and copper(II) porphyrins of the Cretaceous-Tertiary boundary at Stevns Klint (Denmark)
(Earth and Planetary Science Letters, 2000)
High levels of copper(II) (Cu2+) were found with the major part ( GT 90%) of the total Cu located in the smectite (Cu: 175 ppm) and kerogen (Cu: up to 1000 ppm) of the basal black marl of the Cretaceous-Tertiary (KT) ...