210Pb chronologies and depth profiles of stable S isotope ratios (834S) and concentrations of organic and inorganic S fractions were determined in peat cores from nine sites in the U.S. and the Czech Republic. Results indicate that depth profiles in S concentrations, S accumulation, and 634S ratios in peat deposits are affected not only by historical patterns in atmospheric S deposition but also by ongoing depthdependent changes in S reduction-oxidation and S immobilization-mineralization processes within a peat deposit. These processes impart a certain degree of mobility to S in peat, bringing into question the validity of reconstructing historical records of S accumulation using dated peat profiles. Over long-term diagenesis, isotopically light S may be continually released from deep peat. This release may result in redistribution of S and S isotopes in peat and suggests that short-term patterns in S accumulation may not persist over much longer time scales.
A simple apparatus is described whereby any quantity of CO2 up to several moles can be converted to methane in one step by catalytic hydrogenation using a ruthenium catalyst. The conversion is very rapid, the entire operation being carried out in about 3 hours. The over-all yield is greater than 98%, and the methane is of high purity.
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