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Atmospheric transport and deposition of acidic air pollutants

Description: Although general principles which govern atmospheric chemistry of sulfur are understood, a purely theoretical estimation of the magnitude of the processes is not likely to be useful. Furthermore, the data base necessary to make empirical estimates does not yet exist. The sulfur budget of the atmosphere appears to be dominated by man-associated sulfur. The important processes in deposition of man-associated sulfur are wet deposition of sulfate and dry deposition of SO/sub 2/. The relative importance of sulfate and SO/sub 2/ to sulfur deposition (input to watersheds) depends on the air concentrations, and either compound may be the greater contributor depending on conditions. (PSB)
Date: January 1, 1981
Creator: Murphy, C.E. Jr.
Partner: UNT Libraries Government Documents Department

Effect of vegetation on air quality: the value of forest vegetation as a filter for industrial sources of air pollutants

Description: A general model that can be used to estimate the deposition of gaseous pollutants by forests is made with described. Then the model is used to estimate the deposition of fluoride as hydrogen fluoride (HF) around an aluminum refinery. A comparison of spatial and temporal concentration patterns is made with data collected around the ALUAR plant in Puerto Madryn, Argentina. Finally, the area of forest needed to remove a significant portion of the fluoride from the atmosphere is estimated.
Date: January 1, 1980
Creator: Murphy, C.E. Jr. & Ares, J.O.
Partner: UNT Libraries Government Documents Department

Lysimeter study of vegetative uptake from saltstone

Description: At the Savannah River Site, liquid, low-level nuclear waste will be disposed of by incorporating the waste in concrete, a wasteform called saltstone. Saltstone monoliths will then be buried in the earth. To study the potential uptake of radionuclides by trees and other plants growing in the soil in the area containing buried saltstone, a lysimeter study has been in progress since 1984. Thirty two lysimeters were designed, constructed, and filled with soil. Saltstone samples, containing the liquid, low-level supernate from the tank 50 in-tank precipitation demonstration, were buried in some of the lysimeters. Other lysimeters, not containing saltstone, were used as controls. Crops, grass, and trees were planted in the lysimeters and sampled periodically to determine radionuclide concentrations. Water samples were also collected from the lysimeter sumps and analyzed for radionuclide content. This report documents the results of vegetative and lysimeter sump water measurements from the beginning of the project in November of 1984 through September of 1989. 6 refs., 22 figs., 6 tabs.
Date: June 8, 1990
Creator: Murphy, C.E. Jr.
Partner: UNT Libraries Government Documents Department

Environmental transport and cycling of tritium in the vicinity of atmospheric releases. [Savannah River Plant]

Description: Routine releases of tritium to the atmosphere from the Savannah River Plant (SRP) have averaged 5.12 x 10/sup 5/ curies per year during the period 1974 to 1977. Patterns of tritium dispersion in the environment surrounding SRP indicate a power law relationship between air concentration and distance from the source. The relationship between the concentration of tritiated water in vegetation and distance is more complex. A model of the tritium dispersion and cycling in the environment explains the dispersion patterns in terms of the ratio of tritiated hydrogen to tritiated water, climate, and vegetation characteristics. The annual variation in the environmental patterns around the SRP is almost completely determined by the fraction of tritiated hydrogen in the release.
Date: January 1, 1978
Creator: Murphy, C.E. Jr. & Pendergast, M.M.
Partner: UNT Libraries Government Documents Department

Tritium transport around nuclear facilities

Description: The transport and cycling of tritium around nuclear facilities is reviewed with special emphasis on studies at the Savannah River Laboratory, Aiken, South Carolina. These studies have shown that the rate of deposition from the atmosphere, the site of deposition, and the subsequent cycling are strongly influenced by the compound with which the tritium is associated. Tritiated hydrogen is largely deposited in the soil, while tritiated water is deposited in the greatest quantity in the vegetation. Tritiated hydrogen is converted in the soil to tritiated water that leaves the soil slowly, through drainage and transpiration. Tritiated water deposited directly to the vegetation leaves the vegetation more rapidly after exposure. Only a small part of the tritium entering the vegetation becomes bound in organic molecules. However, it appears tht the existence of soil organic compounds with tritium concentrations greater than the equilibrium concentration in the associated water can be explained by direct metabolism of tritiated hydrogen in vegetation.
Date: January 1, 1981
Creator: Murphy, C.E. Jr. & Sweet, C.W.
Partner: UNT Libraries Government Documents Department

The transport, dispersion, and cycling of tritium in the environment. [Contains Bibliography]

Description: The processes which determine transport, dispersion, and cycling of tritium are identified for atmospheric, terrestrial, aquatic, and groundwater systems. The processes are discussed in terms of the storage capacity for tritium in each component of each system and ranges of residence times are derived. The residence times of each component of the systems are discussed in terms of the residence time of the whole system for transient releases of tritium into different components of the systems. The role of the ocean as a sink for tritium is described. The concentration of tritium in the system at steady state is described in terms of the inputs and outputs to the components of the systems. The analysis indicates that the key residence time for a specific release of tritium into the environment is dependent on both the residence time of the components and the means of introduction into the environment. The initial concentration ad residence time of tritium in the terrestrial system after an exposure to tritiated water vapor are determined by the atmospheric and vegetative conditions at the time of the release. The dominant residence time is that of the vegetation. On the other hand, the initial concentration and residence time of tritium in the terrestrial system after an exposure to tritiated hydrogen are determined by the atmospheric and soil conditions at the time of the release. The dominant residence time is that of the soil. The initial concentration and residence time after a liquid release to the soil surface are determined by the diluting soil water content and the residence time for water in the rooting zone of the soil. Little tritium enters the organic fraction of terrestrial systems from transient releases of gases or liquid water. 102 refs., 19 figs., 2 tabs.
Date: January 1, 1990
Creator: Murphy, C.E. Jr.
Partner: UNT Libraries Government Documents Department

The Canadian experimental HT release of June 10, 1987, US measurements

Description: In June 1987, an experiment was performed at the Chalk River Nuclear Laboratories in Ontario, Canada, to study the oxidation of elemental tritium (HT) released to the environment. The experiment involved a 30-minute release of 3.54 TBq (95.7 Ci)of HT to the atmosphere at an elevation of one meter. Scientists from six countries participated in the experiment. The air measurements showed HT concentrations downwind of the release in general agreement with classical atmospheric diffusion (Gaussian) up to the maximum distance measured (400 m). The HTO/HT ratios were shown to slowly increase downwind (approx. 4 x 10/sup /minus/5/ at 50 m to almost 10/sup /minus/3/ at 400 m) as conversion of HT took place. After the release, HTO concentrations in the atmosphere remained elevated. Vegetation samples were also taken since the vegetation and associated soil system have been implicated in the oxidation of HT. Freeze-dried water from vegetation samples was found to be low in HTO immediately after the release suggesting a low direct uptake of HTO in air by vegetation. The tritiated water concentration increased during the first day, peaking during the second day (about 15--30 kBq/L of water at 50 m from the source), and decreasing by the end of the second day. This pattern suggests oxidation in the soil followed by plant uptake through sorption of soil water. This was confirmed by measurements taken by other groups at the experiment site. The HTO in vegetation decreased with distance downwind with the same pattern as the HT measured during the release indicating that the oxidation of HT was linearly related to the HT concentration in the atmosphere during the exposure period. An adequate description of the process can be made through the observed phenomenon of HT deposition into the soil with subsequent rapid oxidation by soil bacteria. 30 refs., ...
Date: September 1, 1988
Creator: Jalbert, R.A. & Murphy, C.E.
Partner: UNT Libraries Government Documents Department

Lampsilis teres, Specimen #317

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an elliptical shape; moderately thick shell; white internal coloring; tan external coloring; no external sculpturing. Collected in the San Jacinto basin. The specimen measures between 100 - 120 mm in length and was assessed to be recently dead when collected.
Date: October 5, 1975
Creator: Boone, Constance; Murphy, C.; Murphy, C. & Boone, Constance
Partner: Elm Fork Natural Heritage Museum

Model for estimating air pollutant uptake by forests: calculation of forest absorption of sulfur dioxide from dispersed sources

Description: The computer model presented in this paper is designed to estimate the uptake of air pollutants by forests. The model utilizes submodels to describe atmospheric diffusion immediately above and within the canopy, and into the sink areas within or on the trees. The program implementing the model is general and can be used with only minor changes for any gaseous pollutant. To illustrate the utility of the model, estimates are made of the sink strength of forests for sulfur dioxide. The results agree with experimentally derived estimates of sulfur dioxide uptake in crops and forest trees. (auth)
Date: January 1, 1975
Creator: Murphy, C.E. Jr.; Sinclair, T.R. & Knoerr, K.R.
Partner: UNT Libraries Government Documents Department

PATCHY SILICA-COATED SILVER NANOWIRES AS SERS SUBSTRATES

Description: We report a class of core-shell nanomaterials that can be used as efficient surface-enhancement Raman scattering (SERS) substrates. The core consists of silver nanowires, prepared through a chemical reduction process, that are used to capture 4- mercaptobenzoic acid (4-MBA), a model analyte. The shell was prepared through a modified Stöber method and consists of patchy or full silica coats. The formation of silica coats was monitored via transmission electron microscopy, UV-visible spectroscopy and phase-analysis light scattering for measuring effective surface charge. Surprisingly, the patchy silica coated silver nanowires are better SERS substrate than silver nanowires; nanomolar concentration of 4-MBA can be detected. In addition, “nano-matryoshka” configurations were used to quantitate/explore the effect of the electromagnetic field at the tips of the nanowire (“hot spots”) in the Raman scattering experiment.
Date: March 29, 2013
Creator: Murph, S. & Murphy, C.
Partner: UNT Libraries Government Documents Department

Toxolasma parvum, Specimen #1115

Description: One preserved mussel specimen including the left valve only. The specimen exhibits an elliptical shape; thick shell; single looped beak sculpturing; white internal coloring; tan external coloring; no external sculpturing. Collected in the Trinity basin. The specimen measures between 0 - 60 mm in length and was assessed to be very-long dead when collected.
Date: October 18, 1974
Creator: Britton, Joseph & Murphy, C.
Partner: Elm Fork Natural Heritage Museum

Toxolasma parvum, Specimen #1116

Description: One preserved mussel specimen including the left valve only. The specimen exhibits an elliptical shape; thick shell; single looped beak sculpturing; white internal coloring; tan external coloring; no external sculpturing. Collected in the Trinity basin. The specimen measures between 0 - 60 mm in length and was assessed to be long dead when collected.
Date: October 18, 1974
Creator: Britton, Joseph & Murphy, C.
Partner: Elm Fork Natural Heritage Museum

Toxolasma parvum, Specimen #1117

Description: One preserved mussel specimen including the right valve only. The specimen exhibits an elliptical shape; thick shell; single looped beak sculpturing; white internal coloring; tan external coloring; no external sculpturing. Collected in the Trinity basin. The specimen measures between 0 - 60 mm in length and was assessed to be long dead when collected.
Date: October 18, 1974
Creator: Britton, Joseph & Murphy, C.
Partner: Elm Fork Natural Heritage Museum

Leptodea fragilis, Specimen #466

Description: One preserved mussel specimen including the right valve only. The specimen exhibits an oval shape; thin shell; double looped beak sculpturing; white internal coloring; tan external coloring; no external sculpturing. Collected in the Red River basin. The specimen measures between 60 - 100 mm in length and was assessed to be very-long dead when collected.
Date: April 25, 1975
Creator: Britton, Joseph & Murphy, C.
Partner: Elm Fork Natural Heritage Museum

Leptodea fragilis, Specimen #467

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an oval shape; thin shell; double looped beak sculpturing; white internal coloring; off-white external coloring; no external sculpturing. Collected in the Red River basin. The specimen measures between 0 - 60 mm in length and was assessed to be very-long dead when collected.
Date: April 25, 1975
Creator: Britton, Joseph & Murphy, C.
Partner: Elm Fork Natural Heritage Museum

Leptodea fragilis, Specimen #468

Description: One preserved mussel specimen including the right valve only. The specimen exhibits an oval shape; thin shell; double looped beak sculpturing; white internal coloring; tan external coloring; no external sculpturing. Collected in the Red River basin. The specimen measures between 0 - 60 mm in length and was assessed to be long dead when collected.
Date: April 25, 1975
Creator: Britton, Joseph & Murphy, C.
Partner: Elm Fork Natural Heritage Museum

Toxolasma parvum, Specimen #1118

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an elliptical shape; thick shell; single looped beak sculpturing; bluish-white internal coloring; tan external coloring; no external sculpturing. Collected in the Red River basin. The specimen measures between 0 - 60 mm in length and was assessed to be relatively-recently dead when collected.
Date: April 25, 1975
Creator: Britton, Joseph & Murphy, C.
Partner: Elm Fork Natural Heritage Museum

Pyganodon grandis, Specimen #764

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a round shape; thin shell; double looped beak sculpturing; white internal coloring; brown external coloring; no external sculpturing. Collected in the Trinity basin. The specimen measures between 60 - 100 mm in length and was assessed to be relatively-recently dead when collected.
Date: October 18, 1974
Creator: Britton, Joseph & Murphy, C.
Partner: Elm Fork Natural Heritage Museum

Pyganodon grandis, Specimen #765

Description: One preserved mussel specimen including the right valve only. The specimen exhibits a round shape; thin shell; double looped beak sculpturing; white internal coloring; tan external coloring; no external sculpturing. Collected in the Trinity basin. The specimen measures between 100 - 120 mm in length and was assessed to be relatively-recently dead when collected.
Date: October 18, 1974
Creator: Britton, Joseph & Murphy, C.
Partner: Elm Fork Natural Heritage Museum

The Uptake of Hydrogen Fluoride by a Forest

Description: A mathematical model of hydrogen fluoride (HF) deposition and accumulation of fluoride in a Eucalyptus rostrata forest has been developed. The model is based on tree physiology and meteorological principles. The data base for the model was derived from a literature survey of the physiological characteristics of E. rostrata and similar eucalyptus species and from current knowledge of meteorological processes in plant canopies.
Date: December 18, 1980
Creator: Murphy, C.E. Jr.
Partner: UNT Libraries Government Documents Department

Tritium Deposition in Pine Trees and Soil from Atmospheric Releases of Molecular Tritium

Description: Much of the tritium found in soil and leaf litter near a chemical separations facility is incorporated into soil organic matter in a stable non-exchangeable form. Formation of this ''bound'' tritium seems to result from the uptake of molecular tritium (HT) by living pine needles. Soil and litter microbes convert HT to HTO more rapidly, but no measurable organic tritium is formed. This report discusses this study.
Date: February 16, 1982
Creator: Murphy, C.E. Jr.
Partner: UNT Libraries Government Documents Department