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Developing Collections of Web-Published Materials

Description: This article discusses collection development practices to meet the unique characteristics of Web-published materials.
Date: 2007
Creator: Hsieh, Inga K.; Murray, Kathleen R. & Hartman, Cathy Nelson
Partner: UNT Libraries

Mechanisms of Radical Removal by SO2

Description: Article on mechanisms of radical removal by SO2.
Date: January 1, 2007
Creator: Rasmussen, Christian Lund; Glarborg, Peter & Marshall, Paul
Partner: UNT College of Arts and Sciences

Assessing Recharge and Geological Model Uncertainty at the Climax Mine Area of the Nevada Test Site

Description: Hydrologic analyses are commonly based on a single conceptual-mathematical model. Yet hydrologic environments are open and complex, rendering them prone to multiple interpretations and mathematical descriptions. Considering conceptual model uncertainty is a critical process in hydrologic uncertainty assessment. This study assesses recharge and geologic model uncertainty for the Climax mine area of the Nevada Test Site, Nevada. Five alternative recharge models have been independently developed for Nevada and the Death Valley area of California. These models are (1) the Maxey-Eakin model, (2 and 3) a distributed parameter watershed model with and without a runon-runoff component, and (4 and 5) a chloride mass-balance model with two zero-recharge masks, one for alluvium and one for both alluvium and elevation. Similarly, five geological models have been developed based on different interpretations of available geologic information. One of them was developed by the U.S. Geological Survey for the Death Valley Regional Flow System (DVRFS) model; the other four were developed by Bechtel Nevada for the Yucca Flat Corrective Action Unit (CAU). The Climax mine area is in the northern part of the Yucca Flat CAU, which is within the DVRFS. A total of 25 conceptual models are thus formulated based on the five recharge and five geologic models. The objective of our work is to evaluate the conceptual model uncertainty, and quantify its propagation through the groundwater modeling process. A model averaging method is applied that formally incorporates prior information and field measurements into our evaluation. The DVRFS model developed by the U.S. Geological Survey is used as the modeling framework, into which the 25 models are incorporated. Conceptual model uncertainty is first evaluated through expert elicitation based on prior information possessed by two expert panels. Their perceptions of model plausibility are quantified as prior model probabilities, which are then updated by the site ...
Date: November 8, 2007
Creator: Ye, M.; Pohlmann, K.; Chapman, J. & Pohll, G.
Partner: UNT Libraries Government Documents Department

The Community Environmental Monitoring Program: Reducing Public Perception of Risk through Stakeholder Involvement

Description: The Community Environmental Monitoring Program (CEMP) has promoted stakeholder involvement, awareness, and understanding of radiological surveillance in communities surrounding the Nevada Test Site (NTS) since 1981. It involves stakeholders in the operation, data collection, and dissemination of information obtained from a network of 29 stations across a wide area of Nevada, Utah and California. It is sponsored by the U.S. Department of Energy, National Nuclear Security Administration’s Nevada Site Office (NNSA/NSO) and administered by the Desert Research Institute (DRI) of the Nevada System of Higher Education. Integration of a near real-time communications system, a public web site, training workshops for involved stakeholders, and educational programs all help to alleviate public perception of risk of health effects from past activities conducted at the NTS.
Date: May 21, 2007
Creator: Hartwell, William T.
Partner: UNT Libraries Government Documents Department

Impacts of interrelated biotic and abiotic processes during the past 125,000 years of landscape evolution in the Northern Mojave Desert, Nevada, USA

Description: Interrelated, biotic (flora and fauna) and abiotic (pedogenesis and hydrology) processes were examined at four sites (30, and approximately 1000-3000, 7000-12,000, and 125,000 years before present) in the northern Mojave Desert. Data collected at each included floral and faunal surveys; soil texture, structure, and morphology; and soil hydraulic properties. Separate measurements were made in shrub undercanopy and intercanopy microsites. At all sites, shrubs made up greater than 86 percent of total perennial cover, being least on the youngest site (4 percent) and most on the 7000-12,000-year-old site (31 percent). In the intercanopy, winter annual density was highest on the 1000- to 3000-year-old site (249 plants/m{sup 2}) and lowest on the oldest site (4 plants/m{sup 2}). Faunal activity, measured by burrow density, was highest on the 1000-3000- and 7000-12,000-year-old sites (0.21 burrows/m{sup 2}) and density was twice as high in the undercanopy versus the intercanopy. Burrow density was lower at the two oldest sites, although density was not statistically greater in the undercanopy than intercanopy. At the older sites, the soil water balance was increasingly controlled by Av horizons in intercanopy soils in which saturated hydraulic conductivity (K{sub sat}) decreased 95 percent from the youngest to the oldest site. No significant reduction in K{sub sat} in undercanopy soils was observed. Decreases in the intercanopy sites correlated with decreases in annual plant density and bioturbation, suggesting these processes are interrelated with surface age.
Date: March 1, 2007
Creator: Shafer, D.S.; Young, M.H.; Zitzer, S.F.; Caldwell, T.G. & McDonald, E.V.
Partner: UNT Libraries Government Documents Department

ABSTRACT: The Community Environmental Monitoring Program: Reducing Public Perception of Risk Through Stakeholder Involvement

Description: Between 1951 and 1992, 928 nuclear tests were conducted at the Nevada Test Site (NTS), including 100 atmospheric and 828 underground tests. Initial public reaction to the tests was largely supportive, but by the late 1950s this began to change, largely as a result of fear of the potential for adverse health effects to be caused by exposure to ionizing radiation resulting from the tests. The nuclear power plant accident at Three Mile Island in 1979 served to heighten these fears, as well as foster a general distrust of the federal agencies involved and low public confidence in monitoring results. Modeled after a similar program that involved the public in monitoring activities around the Three Mile Island nuclear power plant, the Community Environmental Monitoring Program (CEMP) has promoted stakeholder involvement, awareness, and understanding of radiological surveillance in communities surrounding the NTS since 1981. It involves stakeholders in the operation, data collection, and dissemination of information obtained from a network of 29 stations across a wide area of Nevada, Utah, and California. It is sponsored by the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO) and administered by the Desert Research Institute (DRI) of the Nevada System of Higher Education. Since assuming administration of the program in 2000, DRI has accomplished significant enhancements to the network's data collection and transmission capabilities. A robust datalogging and communications system allows for the near real-time transmission of data to a platform maintained by DRI's Western Regional Climate Center, where the data are uploaded and displayed on a publicly accessible web site (http://cemp.dri.edu/). Additionally, the CEMP can serve as part of an emergency response network in the event of an unplanned radiological release from the NTS, and also provides an excellent platform for testing new environmental sensor technologies. Finally, the CEMP ...
Date: February 28, 2007
Creator: Hartwell, T.
Partner: UNT Libraries Government Documents Department

Ciencia y política: perspectiva histórica y modelos alternativos

Description: Article on the relations between science and policy offering an analysis of the historical antecedents of the policy of science and comparative data and ethical reflections on the policy of scientific budget.
Date: April 2007
Creator: Mitcham, Carl & Briggle, Adam
Partner: UNT College of Arts and Sciences

The Autecology of the Fío-Fío (Elaenia Albiceps Lafresnaye and D'Orbigny) in Subantarctic Forests of the Cape Horn Biosphere Reserve, Chile

Description: Article discussing research on the autecology of the fío-fío (Elaenia albiceps Lafresnaye and D'Orbigny) in subantarctic forests of the Cape Horn Biosphere Reserve, Chile.
Date: 2007
Creator: Brown, Clare E.; Anderson, Christopher B.; Ippi, Silvina; Sherriffs, Margaret; Charlin, Rina; McGehee, Steven M. et al.
Partner: UNT College of Arts and Sciences

Combined Experimental and Computational Study of TpRu{P(pyr)3} (NCMe)Me (pyr = N-pyrrolyl): Inter- and Intramolecular Activation of C-H Bonds and the Impact of Sterics on Catalytic Hydroarylation of Olefins

Description: This article discusses a combined experimental and computational study of TpRu{P(pyr)3} (NCMe)Me (pyr = N-pyrrolyl).
Date: October 4, 2007
Creator: Foley, Nicholas A.; Lail, Marty; Gunnoe, T. Brent; Cundari, Thomas R., 1964-; Boyle, Paul D. & Petersen, Jeffrey L.
Partner: UNT College of Arts and Sciences