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Basin Analysis Of The Central Grand Wash Trough, Northwest Arizona: New Insights Into A Miocene Extensional Basin, Nathan Robert Suurmeyer

UNLV Retrospective Theses & Dissertations

The Grand Wash trough (GWT), a Miocene extensional basin in the Lake Mead region, had been interpreted by previous workers as a rift basin. This study's objective was to test this interpretation by analyzing basin deposits using stratigraphic sections, geologic mapping, and a gravity survey. The results reveal that the structure of the GWT and its axial and foot wall derived deposits resemble those of a rift basin. However, the basin is too shallow (∼1 km) and the hanging wall alluvial fan is larger and coarser grained than those in previously described rift basins. Instead, these aforementioned characteristics are comparable …

Exotic Annual Plant Invasions And Their Relationships To Roads And Native Perennial Species In The Mojave Desert, Southwestern Usa, Donovan J. Craig, Jill Pacovsky Craig, Scott R. Abella

Vegetation Monitoring Presentations

For the last five years, roadside monitoring for exotic invasive species has been a common practice for documenting distributions in Clark County, Nevada (Abella et al., in press). Yet, studies have shown that weed relationships to road corridors differ depending upon the natural system (Hansen and Clevenger, 2005). In the Mojave Desert, it is unknown whether exotic species are limited to or even predominant along roadsides.

Compounding this uncertainty, fertile islands under shrubs are known to enhance conditions for many annuals (Thompson et al., 2005). Thus, a site’s shrub composition could influence exotic invasive plant distributions.

Implications For Management Prioritization Of Exotic Annual Weed Monitoring Near Roadsides In The Eastern Mojave Desert, Usa, Donovan J. Craig, Jill E. Craig, Scott R. Abella, Public Lands Institute,

Vegetation Monitoring Presentations

Invasive exotic plants provide an unnatural conduit for fires in the Mojave Desert. For the last five years, roadside monitoring for exotic invasive species has been a common practice for documenting distributions in Clark County, Nevada (Abella et al., in press). Yet, studies have shown that weed relationships to road corridors differ depending upon the natural system (Hansen and Clevenger, 2005). In the Mojave Desert, it is unknown whether exotic species are limited to or even predominant along roadsides.

Compounding this uncertainty, fertile islands under shrubs are known to enhance conditions for many annuals (Thompson et al., 2005). Thus, a …

University Of Nevada, Las Vegas Transmutation Research Program Annual Progress Report Academic Year 2007-2008, Anthony Hechanova, Rebecca Paulson

Transmutation Research Program Reports (TRP)

It is my pleasure to present the UNLV Transmutation Research Program’s seventh annual report that highlights the academic year 2007-2008. Supporting this document are the many technical reports and theses that have been generated over the past seven years.

In the seventh year of our program, we continued to see growth in the Radiochemistry Ph.D. program with a total of 20 students in the fourth year of the program (we anticipated twelve in the program proposal). Since our inception, the program has sponsored to their conclusion 48 M.S. and 6 Ph.D. degrees. The program supported 53 graduate students, 11 undergraduates, …

Immobilization Of Fission Iodine By Reaction With A Fullerene Containing Carbon Compound And Insoluble Natural Matrix, Spencer M. Steinberg, Gary Cerefice, David W. Emerson

Separations Campaign (TRP)

Observations related to the oxidation of iodide to iodine (I₂) or hypoiodic acid (HIO) by MnO₂ were continued. The formation of triiodide presumable involves the adsorption of iodide onto the MnO₂ surface (perhaps displacing a surface hydroxyl group). The iodide should be subsequently oxidized and released back into solution as IOH or I₂, which rapidly forms I₃ ^-. The kinetic data has been modeled as a first order process. First order rate constants have been obtained for the formation of iodine in the presence of MnO₂. The increase in iodide …

Fundamental Chemistry Of U And Pu In The Tbp-Dodecane-Nitric Acid System, Kenneth Czerwinski

Separations Campaign (TRP)

The research objective is to experimentally evaluate the fundamental speciation of Pu and U in the TBP-dodecane-nitric acid- AHA system and the effect of pertechnetate, specifically:

• To determine the influence of nitrate on the speciation of U and Pu in the TBP-dodecane-nitric acid system. The aqueous and organic speciation of U and Pu are examined as a function of the nitric acid concentration, nitrate concentration, actinide ion concentration, temperature, and time.

• To determine the speciation of U and Pu with AHA in the presence and absence of TBP-dodecane organic phase. The aqueous and organic speciation of U and …

Evaluation Of Fundamental Radionuclide Extraction Data For Urex, Kenneth Czerwinski

Separations Campaign (TRP)

The speciation of technetium and actinides in advanced solvent extraction systems is the basis for their manipulation in separations. The ability to understand and predict radionuclide speciation is paramount to successful modeling of proposed separation systems. This project will examine the speciation of radionuclides in different stages of the uranium extraction (UREX) separation scheme, providing data useful to modeling. The areas to be examined include the speciation of uranium and plutonium with tributylphosphate and the kinetics and thermodynamics of lanthanides and actinides in the TALSPEAK (Trivalent actinide lanthanide separation by phosphorous reagent extraction from aqueous complexes) system. The complexation constants …

Separation Of Technetium From Uranium And Waste Form Synthesis, Kenneth Czerwinski

Waste Forms Campaign (TRP)

In this project, systematic investigations on the Tc-Zr binary metal system will be evaluated for the first time. The synthesis of metallic Tc as well as its alloys with Zr will be evaluated. In order to provide valuable data to AFC R&D, the thermodynamic equilibrium phases, as well as their performance under repository conditions, will be examined.

The research objectives of this project are as follows:

• Evaluate anion exchange methods for achieving the separation of Tc from U.

• Synthesize metallic Tc from the separated product.

• Synthesize and characterize Tc alloys.

• Investigate Tc-corrosion and Tc-leaching of binary …

Evaluation Of Cs/Sr Waste Form For Long Term Storage And Disposal, Gary Cerefice, Longzhou Ma

Waste Forms Campaign (TRP)

To facilitate long-term storage, the disposal containers will need to be able to survive for the entire storage interval. The first aspect of the project will explore the potential interaction of the aluminosilicate waste form with the storage canister materials to determine if there is any corrosion or chemical interaction concerns for the storage of the materials. At the end of the storage interval, most of the cesium (¹³⁷Cs) in the waste form will have decayed to its daughter, barium (¹³⁷Ba). While this decay provides a significant reduction in the decay heat generated by the waste …

Mojave Applied Ecology Notes Winter 2008, Scott R. Abella, E. Cayenne Engel, Jill E. Craig

Mojave Applied Ecology Notes

Mojave Desert collaborative projects, fire history in Spring Mountains, Northshore Road rehabilitation, wildfires and invasive plants in American deserts conference, weed sentry surveys

The Effects Of Electromagnetic Fields On The Detection Of Mercury And Radionuclides, Yogendra M Panta

UNLV Retrospective Theses & Dissertations

Mercury and many radionuclides are extremely toxic, and their monitoring and detection are of importance for human health and environmental protection. This dissertation focuses on the detection of mercury (II) ions and radionuclides including uranium (234U and 238U), plutonium (239Pu), and americium (241Am) in aqueous solutions under the effects of electromagnetic fields. The stripping electrochemical method has been widely used to detect mercury (II) ions in aqueous solutions. To enhance the detection sensitivity of the conventional electrochemical method, mechanically stirring the solution is usually performed to enhance the rate of the ionic mass transport. Instead of mechanically stirring the solution; …

Modeling Natural Resource Scarcity And Poverty Effects On Fertility In Honduras, Nepal, And Tanzania, Ayoub Shaban Ayoub

UNLV Retrospective Theses & Dissertations

This dissertation examines whether the vicious circle theory applies in three developing countries characterized by high population growth. According to the vicious circle theory, natural resource scarcity coupled with poverty leads to population growth via positive effects on fertility particularly in rural areas of developing countries. Population growth then leads to a further increase in natural resource scarcity, creating a "feedback loop." This is the first study to use micro-level data to test and control for endogeneity using a two-stage Probit model (IVPROBIT). The existing literature has largely failed to address endogeneity in the relationship between natural resource scarcity and …

A Systematic Approach To An Integrated Curriculum Model For Dental Education, Tanis Maria Stewart

UNLV Retrospective Theses & Dissertations

The purpose of this quantitative study was to determine the degree of curriculum integration within dental schools in North America. The intent of the study was to determine how an adaptation of the Fogarty (1991) framework of integration exhibits itself in dental education; An electronic survey conducted of the Academic Deans of dental schools in the United States and Canada resulted in a response rate of 54.09% (33/61). Frequencies, chi-square and Spearman rho (p) correlation coefficient were used for the statistical analyses of data; All survey respondents reported that their curricula include all levels of integration which comprise the adapted …

Characterization Of The Mechanism Of Bi-Layer Oxide Growth On Austenitic Stainless Steels 316l And D9 In Oxygen-Controlled Lead-Bismuth Eutectic (Lbe), Daniel Koury

UNLV Retrospective Theses & Dissertations

Lead Bismuth Eutectic (LBE) has been proposed for use in programs for accelerator-based and reactor-based transmutation of nuclear waste. LBE is a leading candidate material as a spallation target (in accelerator-based transmutation) and an option for the sub-critical blanket coolant. The corrosion by LBE of annealed and cold-rolled 316L stainless steels, and the modified austenitic stainless steel alloy D9, has been studied using Scanning Electron Microscopy (SEM), Electron Probe Micro Analysis (EPMA), and X-ray Photoelectron Spectroscopy (XPS). Exposed and unexposed samples have been compared and the differences studied. Small amounts of surface contamination are present on the samples and have …

Examining Unused Pharmaceuticals In The Environment, Ilene Sue Ruhoy

UNLV Retrospective Theses & Dissertations

Unused pharmaceuticals take an unhealthy toll on both the environment and human health. In the US alone, an estimated {dollar}1 billion of prescription drugs are thrown away each year. Increasing availability, marketing, and purchasing of both prescription and over-the-counter medications, coupled with the tendency of patients to discontinue use of and to stockpile drugs at home, is a unique problem that has garnered increasing attention among scientists, policymakers, and the media in the last ten years; These accumulated household drugs become unused pharmaceutical waste. This waste must be discarded and disposed of by the consumer. Historically, consumers have been instructed …

Evaluating The Use Of System Dynamics For Improving Stakeholder Decision Making, Marcia Lynne Turner

UNLV Retrospective Theses & Dissertations

When lay stakeholders are involved in complex environmental decision making, the ensuing decision does not always effectively solve the problem of focus. This can be due to the fact that standard facilitation methods commonly used to manage such efforts frequently fail to promote thorough and rational decision analysis. A review of classical and behavioral decision theory, stakeholder research and standard facilitation practices suggests that standard facilitation methods tend to enable behavioral decision making strategies which oversimplify decision making tasks, rather than employing classical rational strategies which stress a more thorough decision analysis and maximization of decision outcomes; To test this …

Modeling The Unsaturated Zone At The Area 5 Radioactive Waste Management Site: Effects Of Climate Change And Vegetation On Flow Conditions, Amanda Marie Brandt

UNLV Retrospective Theses & Dissertations

This thesis tests a series of potential future climate scenarios and associated environmental conditions that could result in the reversal of the present upward hydraulic gradient in the vadose zone at the Area 5 Radioactive Waste Management Site (RWMS) by implementing a one-dimensional model developed using the HYDRUS 1-D numerical modeling package. The research is divided into two phases. Phase I simulates the system from the Pleistocene to Holocene transition (approximately 13,000 years ago) to the present and is tested by independently varying precipitation, evaporation and transpiration rates. The results provide initial conditions for subsequent modeling under Phase II, which …

The Relationship Between Gestational Pcb Exposure, Thyroid Hormones And Adhd, Vicki M Tripoli

UNLV Retrospective Theses & Dissertations

PCB exposure has been associated with a reduction in circulating thyroid hormones via several different mechanisms. While thyroid hormones can influence many physiological endpoints in adults, precise concentrations during critical periods of gestation are crucial to normal development. Maternal consumption of PCB contaminated fish has been associated with developmental problems in animals and humans. Alterations of thyroid hormones is postulated to be one possible source of the developmental latencies associated with PCB exposure. Thus, this study investigated the influence of maternal thyroxine supplements in rodents exposed to a low dose of commercial PCBs; Pregnant Long-Evans rats were exposed to one …

Impact Of The Synthesis Process On Structure Properties For Afci Fuel Candidates, Kenneth Czerwinski

Fuels Campaign (TRP)

The research objectives are:

• To explore a low-temperature fluoride route to synthesize actinide nitrides. • To characterize actinide nitrides structurally and thermally.

• To use high resolution TEM techniques to explore the microstructure of the radioactive samples.

Solution-Based Synthesis Of Nitride Fuels, Kenneth Czerwinski, Tyler A. Sullens

Fuels Campaign (TRP)

One of the original synthetic routes devised for the synthesis of U (III)N involved the entire reaction taking place in liquid ammonia. Several experimental reactions were conducted in an attempt to synthesize the UI₃(NH₃)_x and U(NH₂)₃(NH₃)_x precursors of U(III) N. Each attempt involved cleaning of the uranium metal to remove the oxide coating of the metal reagent with 3 washes of concentrated nitric acid, each followed by a rinse with liquid ammonia. Success of this cleaning procedure was varied, with a majority of cleaned metal oxidizing rapidly once …

Comparing Values For A Private Environmental Good, Xeriscape: Hedonic Price Method Versus Contingent Valuation Method, Carole Ann Rollins

UNLV Retrospective Theses & Dissertations

The hedonic price method (HPM) and the contingent valuation method (CVM) are two valuation techniques used to estimate and report benefits of public and private environmental goods. Both methods are used in comparison studies for public goods, but not for private goods. The purpose of this study is to extend the knowledge of economic valuation for a private good by comparing a reported value from a contingent valuation survey with an estimate from the HPM using the application of xeriscape landscaping in residential settings. Market data were collected from 500 residential locations in Clark County, Nevada; of this sample, 250 …

A System Dynamics Approach To Water Resources Planning And Management In South Florida, Dinesh Kumar Prashar

UNLV Retrospective Theses & Dissertations

The primary aim of this research is to test a number of policy options to reduce water consumption in agricultural and municipal sectors, and quantify its impact on environmental supply. A System Dynamics model is developed to evaluate the sustainability of agricultural, municipal, and environmental water demands in South Florida. Performance criteria of vulnerability, resilience, and reliability, are used to measure the success of the policies. In addition, scenarios with varying precipitation and population growth rates are generated to account for uncertainty; The status-quo simulations run from 1970 to 2050 show a reduction in environmental flows after 2010. That can …

Understanding The Motivations Of Rock Climbers: A Social Worlds Study, Amy Miller Ansari

UNLV Theses, Dissertations, Professional Papers, and Capstones

Rock climbing affects public lands through erosion, destruction of vegetation, and disturbance to historical sites. Minimum impact messages can help reduce impacts but requires understanding characteristics of the message recipient. The purpose of this study was to understand the motivations of rock climbers to help land managers design more effective minimum impact messages. This study assesses the motivations of rock climbers using a social worlds approach, focusing on the sub-worlds of. traditional climbers, sport climbers, and boulderers. I found that traditional climbers are most motivated to pursue a wilderness experience, climb in a natural wilderness setting, and climb in quiet …

Inside Unlv, Shane Bevell, David Ashley, Tony Allen, Mamie Peers, Allison Miller

Inside UNLV

No abstract provided.

Proposing Measures For Assessing Systems Thinking Interventions, Megan Aline Hopper

UNLV Theses, Dissertations, Professional Papers, and Capstones

This paper presents an analysis of systems thinking interventions in educational settings. Although these interventions have been implemented in K-12 classrooms since the mid 1980s, there is still no clear definition of systems thinking or identification of the best method to test the effectiveness of interventions or methods for teaching systems thinking The goal of this paper is to answer the question: how do we assess the effectiveness of systems thinking interventions in education? In order to answer this question, I had to address the following sub questions: (1) what is systems thinking, (2) what systems thinking interventions are being …

Ground Water Level Measurements In Selected Boreholes Near The Site Of The Proposed Repository, H. Scott Page, Klaus J. Stetzenbach, Amy J. Smiecinski

Publications (YM)

The purpose of this report is to summarize the work and present conclusions of Project Activity Task FY-04-005 conducted under DE-FC28-04RW12232 between the U.S. Department of Energy and the Nevada System of Higher Education (NSHE). The work was conducted in the Harry Reid Center for Environmental Studies of the University of Nevada – Las Vegas from Oct 1, 2003 to Sept 30, 2007.

Inside Unlv, Cate Weeks, Diane Russell, David Ashley, Grace Russell

Inside UNLV

No abstract provided.

Concurrent Panel Session 1: Environmental Sustainability And Las Vegas, Dale A. Devitt, David E. James, Patricia Mulroy, Alan O'Neill, Thomas C. Piechota, Doug Selby, Krystyna Anne Stave, Michael Yackira, Bruce Turner

Shaping the Future of Southern Nevada: Economic, Environmental, and Social Sustainability

Moderator: Dr. Stan Smith, UNLV School of Life Sciences Scribe: Crystal Jackson, UNLV Department of Sociology Conference white paper & Full summary of panel session, 6 pages

Shaping The Future Of Southern Nevada Moderators & Panelists Biographies

Shaping the Future of Southern Nevada: Economic, Environmental, and Social Sustainability

Moderators & Panelists biographies

Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Quarterly Progress Report, Period Ending: October 1, 2007, Limnological Assistance For Lake Mead National Recreation Area

Limnological Studies

• Task Agreement has been formally executed

• Position description and announcement have been drafted for limnologist position

• All projects have been initiated