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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

Pyrolysis-mass spectrometry/pattern recognition on a well-characterized suite of humic samples Pyrolysis-mass spectrometry/pattern recognition on a well-characterized suite of humic samples

A suite of well-characterized humic and fulvic acids of freshwater, soil and plant origin was subjected to pyrolysis-mass spectrometry and the resulting data were analyzed by pattern recognition and factor analysis. A factor analysis plot of the data shows that the humic acids and fulvic acids can be segregated into two distinct classes. Carbohydrate and phenolic components are more...
Authors
P. MacCarthy, S.J. DeLuca, K.J. Voorhees, Ronald L. Malcolm, E.M. Thurman

Simulation of steady-state flow in three-dimensional fracture networks using the boundary-element method Simulation of steady-state flow in three-dimensional fracture networks using the boundary-element method

An efficient method for simulating steady-state flow in three-dimensional fracture networks is formulated with the use of the boundary-element method. The host rock is considered to be impervious, and the fractures can be of any orientation and areal extent. The fractures are treated as surfaces where fluid movement is essentially two-dimensional. Fracture intersections are regarded as...
Authors
A.M. Shapiro, J. Andersson

Error bounds in cascading regressions Error bounds in cascading regressions

Cascading regressions is a technique for predicting a value of a dependent variable when no paired measurements exist to perform a standard regression analysis. Biases in coefficients of a cascaded-regression line as well as error variance of points about the line are functions of the correlation coefficient between dependent and independent variables. Although this correlation cannot be...
Authors
M.R. Karlinger, B.M. Troutman

Partition coefficients of organic compounds in lipid-water systems and correlations with fish bioconcentration factors Partition coefficients of organic compounds in lipid-water systems and correlations with fish bioconcentration factors

Triolein-water partition coefficients (KtW) have been determined for 38 slightly water-soluble organic compounds, and their magnitudes have been compared with the corresponding octanol-water partition coefficients (KOW). In the absence of major solvent-solute interaction effects in the organic solvent phase, the conventional treatment (based on Raoult's law) predicts sharply lower...
Authors
C. T. Chiou

Culturing Selenastrum capricornutum (Chlorophyta) in a synthetic algal nutrient medium with defined mineral particulates Culturing Selenastrum capricornutum (Chlorophyta) in a synthetic algal nutrient medium with defined mineral particulates

Algal nutrient studies in chemically-defined media typically employ a synthetic chelator to prevent iron hydroxide precipitation. Micronutrient-particulate interactions may, however, significantly affect chemical speciation and hence biovailability of these nutrients in natural waters. A technique is described by which Selenastrum capricornutum Printz (Chlorophyta) may be cultured in a...
Authors
James S. Kuwabara, J.A. Davis, Cecily C.Y. Chang

Unit hydrograph approximations assuming linear flow through topologically random channel networks Unit hydrograph approximations assuming linear flow through topologically random channel networks

The instantaneous unit Hydrograph (IUH) of a drainage basin is derived in terms of fundamental basin characteristics (Z, α, β), where α parameterizes the link (channel segment) length distribution, and β is a vector of hydraulic parameters, Z is one of three basin topological properties, N, (N, D), or (N, M), where N is magnitude (number of first-order streams), D is diameter (mainstream...
Authors
Brent M. Troutman, Michael R. Karlinger

Migration of wood-preserving chemicals in contaminated groundwater in a sand aquifer at Pensacola, Florida Migration of wood-preserving chemicals in contaminated groundwater in a sand aquifer at Pensacola, Florida

Operation of a wood-preserving facility for nearly 80 years at Pensacola, FL, contaminated the near-surface groundwater with creosote and pentachlorophenol. The major source of aquifer contamination was unlined surface impoundments that were in direct hydraulic contact with the groundwater. Episodes of overtopping the impoundments and overland flow of treatment liquor and waste were also
Authors
D.F. Goerlitz, D.E. Troutman, E.M. Godsy, B.J. Franks

Assessment of long-term salinity changes in an irrigated stream-aquifer system Assessment of long-term salinity changes in an irrigated stream-aquifer system

Changes in salinity in groundwater and surface water in the Arkansas River valley of southeastern Colorado are primarily related to irrigation practices. A solute transport model was applied to an 11-mile reach of the valley to compute salinity changes in response to spatially and temporally varying stresses. The model was calibrated in 1973 using detailed field measurements made during...
Authors
Leonard F. Konikow, Mark Person

Partitioning studies of coal-tar constituents in a two-phase contaminated ground-water system Partitioning studies of coal-tar constituents in a two-phase contaminated ground-water system

Organic compounds derived from coal-tar wastes in a contaminated aquifer in St. Louis Park, Minnesota, were identified, and their partition coefficients between the tar phase and aqueous phase were determined and compared with the corresponding n-octanol/water partition coefficients. Coal tar contains numerous polycyclic aromatic compounds, many of which are suspected carcinogens or...
Authors
Colleen E. Rostad, W. E. Pereira, M. F. Hult

Geochemistry of great Salt Lake, Utah II: Pleistocene-Holocene evolution Geochemistry of great Salt Lake, Utah II: Pleistocene-Holocene evolution

Sedimentologic and biostratigraphic evidence is used to develop a geochemical model for Great Salt Lake, Utah, extending back some 30,000 yrs. B.P. Hydrologie conditions as defined by the water budget equation are characterized by a lake initially at a low, saline stage, rising by about 17,000 yrs. B.P. to fresh water basin-full conditions (Bonneville level) and then, after about 15,000...
Authors
R. J. Spencer, H.P. Eugster, B.F. Jones

Geochemistry of Great Salt Lake, Utah I: Hydrochemistry since 1850 Geochemistry of Great Salt Lake, Utah I: Hydrochemistry since 1850

The hydrochemistry of Great Salt Lake, Utah, has been defined for the historic period, 1850 through 1982, from published data combined with new observations. The water balance depends largely on river inflow, atmospheric precipitation onto the lake surface and evaporation. Input of the major solutes can best be accounted for by mixing dilute calcium-bicarbonate type river waters with...
Authors
R. J. Spencer, H.P. Eugster, B.F. Jones, S.L. Rettig
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