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Publications

Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).

Filter Total Items: 3785

Flame ionization mass spectrometry--Isotope ratio determinations for potassium Flame ionization mass spectrometry--Isotope ratio determinations for potassium

The air/acetylene flame provides a convenient ion source for the determination of potassium isotopic ratios by mass spectrometry. Unlike the argon inductively coupled plasma (ICP), the flame provides low background in the mass region of interest. Ion production is quite satisfactory for isotope ratio measurements at the micrograms per milliliter (μg/mL) level and slightly below, with 1...
Authors
Howard E. Taylor, John R. Garbarino, S. R. Koirtyohann

Formation and transport of deethylatrazine in the soil and vadose zone Formation and transport of deethylatrazine in the soil and vadose zone

Atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) and two degradation products were monitored at seven depths in the soil and vadose zone throughout the growing season in two experimental plots in which corn (Zea mays L.) was grown. The soils in these plots were a Kimo silty clay loam (clayey over loamy, montmorillonitic, mesic, Fluvaquentic Hapludoll) and a Eudora silt loam...
Authors
C.D. Adams, E.M. Thurman

In situ bacterial selenate reduction in the agricultural drainage systems of western Nevada In situ bacterial selenate reduction in the agricultural drainage systems of western Nevada

Dissimilatory in situ selenate reduction to elemental selenium in sediments from irrigated agricultural drainage regions of western Nevada was measured at ambient Se oxyanion concentrations. Selenate reduction was rapid, with turnover rate constants ranging from 0.04 to 1.8 h-1 at total Se concentrations in pore water of 13 to 455 nM. Estimates of removal rates of selenium oxyanions were...
Authors
R.S. Oremland, N.A. Steinberg, T. S. Presser, L.G. Miller

In situ measurement of methane oxidation in groundwater by using natural-gradient tracer tests In situ measurement of methane oxidation in groundwater by using natural-gradient tracer tests

Methane oxidation was measured in an unconfined sand and gravel aquifer (Cape Cod, Mass.) by using in situ natural-gradient tracer tests at both a pristine, oxygenated site and an anoxic, sewage-contaminated site. The tracer sites were equipped with multilevel sampling devices to create target grids of sampling points; the injectate was prepared with groundwater from the tracer site to...
Authors
R. L. Smith, B.L. Howes, S. P. Garabedian
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