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1993
Chen, RF, Bada JL, Suzuki Y.  1993.  The Relationship between Dissolved Organic-Carbon (Doc) and Fluorescence in Anoxic Marine Porewaters - Implications for Estimating Benthic Doc Fluxes. Geochimica Et Cosmochimica Acta. 57:2149-2153.   10.1016/0016-7037(93)90102-3   AbstractWebsite

Fluorescence and dissolved organic carbon (DOC) measurements of porewaters from the Santa Barbara Basin, the Guaymas Basin, and the upper sections of the Nankai Trough suggest that ultraviolet fluorescence (lambda(ex) = 325 nm, lambda(em) = 450 nm) may be used as a first order estimate of DOC in anoxic marine porewaters. The majority of porewater organic carbon appears to be fluorescent, while a constant approximately 1 mM DOC, probably the low molecular weight compounds, is not fluorescent. These data are consistent with a model in which low molecular weight compounds dissolved in porewater act as the common intermediate between labile sedimentary organic matter and remineralization or polymerization products. Fluorescence may also be used to sensitively estimate benthic DOC fluxes to the overlying water column. Results from the Santa Barbara Basin, if representative of global anoxic oceanic regions, indicate that DOC release from anoxic sediments is not a major source of oceanic DOC when compared to internal recycling rates, but may be comparable to external input or permanent removal processes.

1992
Zenobi, R, Philippoz JM, Zare RN, Wing MR, Bada JL, Marti K.  1992.  Organic-Compounds in the Forest Vale, H4 Ordinary Chondrite. Geochimica Et Cosmochimica Acta. 56:2899-2905.   10.1016/0016-7037(92)90366-q   AbstractWebsite

We have analyzed the H4 ordinary chondrite Forest Vale for polycyclic aromatic hydrocarbons (PAHs) using two-step laser mass spectrometry (L2MS) and for amino acids using a standard chromatographic method. Indigenous PAHs were identified in the matrices of freshly cleaved interior faces but could not be detected in pulverized silicates and chondrules. No depth dependence of the PAHs was found in a chipped interior piece. Amino acids, taken from the entire sample, consisted of protein amino acids that were nonracemic, indicating that they are terrestrial contaminants. The presence of indigenous PAHs and absence of indigenous amino acids provides support for the contention that different processes and environments contributed to the synthesis of the organic matter in the solar system.

1990
Chen, RF, Bada JL.  1990.  A Laser-Based Fluorometry System for Investigations of Seawater and Porewater Fluorescence. Marine Chemistry. 31:219-230.   10.1016/s0304-4203(05)80014-3   AbstractWebsite

A highly sensitive laser-induced fluorescence (LIF) system has been developed to study the fluorescence of dissolved organic carbon (DOC) in the marine environment. The LIF detector has a detection limit of approximately 10 attomoles (10x10(-18) moles) of pterin and eliminates internal quenching in highly fluorescent samples such as anoxic porewaters encountered when using conventional fluorometry. LIF analysis is rapid, reproducible, and uses only 100 mu-l of a sample. This small size requirement permits fluorescence analyses of samples often available only in limited amounts, such as pore-waters, hydrothermal vent waters, and rainwaters. In addition, the LIF detection system may greatly simplify extraction and separation procedures required to characterize the fluorescent components of DOC.