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2008

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Understanding The Motivations Of Rock Climbers: A Social Worlds Study, Amy Miller Ansari Jan 2008

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 …


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

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 Jan 2008

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 Jan 2008

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 Jan 2008

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 Jan 2008

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 Jan 2008

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 Jan 2008

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 Jan 2008

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 Jan 2008

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 Jan 2008

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 Jan 2008

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 Jan 2008

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 Jan 2008

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 Jan 2008

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 Jan 2008

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 Jan 2008

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 Jan 2008

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 …


Summer 2008 Jan 2008

Summer 2008

University of Richmond Magazine

No abstract provided.


The World Trade Center Disaster: Health Effects And Compensation Mechanisms, John Howard Jan 2008

The World Trade Center Disaster: Health Effects And Compensation Mechanisms, John Howard

Journal of Law and Policy

No abstract provided.


Effective Teaching & Teaching Evaluation Practices: Canadian University Geography Departments, Susan Vajoczki Jan 2008

Effective Teaching & Teaching Evaluation Practices: Canadian University Geography Departments, Susan Vajoczki

Theses and Dissertations (Comprehensive)

In this thesis teaching evaluation practices in Canadian university geography departments are examined. The objective of this research is to identify good practices for teaching evaluation that can be applied within geography departments at Canadian universities and may be applicable to other departments and within other countries. In order to meet this goal a number of research questions were identified. These include:

  1. What is effective teaching in higher education?;
  2. What is effective teaching within the discipline of geography in higher education?;
  3. How and why is teaching evaluated in higher education?;
  4. What is the breadth of teaching evaluation practices currently used …


A Critical Examination Of Sustainability Considerations In Yukon Environmental Assessment—Past And Present, Louisa M. Clementino Jan 2008

A Critical Examination Of Sustainability Considerations In Yukon Environmental Assessment—Past And Present, Louisa M. Clementino

Theses and Dissertations (Comprehensive)

The Northern regions of Canada, as a result of landscape characteristics and political and cultural dynamics, present unique challenges and opportunities for meeting sustainability goals through environmental assessment (EA) processes. In order to understand the significance of the EA process in the North and its applicability to fulfilling sustainability goals, the past and present EA regimes of the Yukon are evaluated adopting a sustainability-focused framework. Unique changes to the Yukon EA process, as a result of land claim agreements and devolution have created innovative structures and processes, reflective of the environmental, socio-economic, cultural and political circumstances of the region. The …


The Traditional Wilderness Conception, Postmodern Cultural Constructionism And The Importance Of Physical Environments, Matthew Adam Gray Jan 2008

The Traditional Wilderness Conception, Postmodern Cultural Constructionism And The Importance Of Physical Environments, Matthew Adam Gray

Graduate Student Theses, Dissertations, & Professional Papers

Recently, a heated debate has emerged between advocates of the traditional wilderness concept and those who believe that this concept is merely a cultural construction. The traditional wilderness conception viewed wilderness as an objective place separate from humans that is defined by being primarily shaped by natural forces, possessing natural origins and being free of human inhabitants and structures. This view culminated in the definition of wilderness featured in the 1964 Wilderness Act. A postmodern critique of the traditional wilderness conception began in the 1980s. In this view, the traditional wilderness conception is thought to be a product of Euro- …


Hydrological Response Patterns And Solute Flux In Canadian Shield Basins: Role Of Different Physical Features And Antecedent Moisture Conditions, Jessica Mueller Jan 2008

Hydrological Response Patterns And Solute Flux In Canadian Shield Basins: Role Of Different Physical Features And Antecedent Moisture Conditions, Jessica Mueller

Theses and Dissertations (Comprehensive)

Patterns of stream flow in relatively undisturbed Canadian Shield basins are closely linked to their physical and vegetative characteristics and meteorological conditions. The physical characteristics include topography, soil-till composition, depth and structure, slope morphology and bedrock geology. Hydrological flowpaths through, and in-situ chemical processes in the soil-till matrix are influenced greatly by the composition of these features and by the antecedent hydrological conditions preceding a given storm or snowmelt event.

A long term data set, collected by the Dorset Environmental Science Centre, is used to examine eight forested basins within the Muskoka-Haliburton region of south-central Ontario. The basins have a …


Intra-Urban Analysis Of Commercial Locations: A Gis-Based Approach, Christopher D. Storie Jan 2008

Intra-Urban Analysis Of Commercial Locations: A Gis-Based Approach, Christopher D. Storie

Theses and Dissertations (Comprehensive)

The urban landscape is an interspersed mixing of residences, shops, theaters, parks, natural areas, and a multitude of other uses. From the early days of the central markets, to the planned downtown, to the heavily planned super-regional shopping complexes, commercial landscapes evolve. There has been considerable research conducted on analyzing the commercial structure of urban environments in an attempt to better understanding the nature of retailing and its resultant impacts on the geography of the city.

This research has three broad goals: a) to develop a technique that makes operational, in a systematized and objective manner, an approach to analyzing …


Disciplinary Differences In Preferred Research Methods: A Comparison Of Groups In The Biglan Classification Scheme, Mark A. Alise Jan 2008

Disciplinary Differences In Preferred Research Methods: A Comparison Of Groups In The Biglan Classification Scheme, Mark A. Alise

LSU Doctoral Dissertations

The Biglan system of classifying disciplines in groups based on similarities and differences in their subject matter has been validated in numerous empirical studies. The present study sought to expand that validation by comparing two Biglan groups that include disciplines representing the social and behavioral sciences. As a unique point of comparison, preferred research methods were contrasted between Psychology and Sociology forming one group of pure disciplines and Education and Nursing forming another group of applied disciplines. A code sheet was developed to categorize the various components of published research, distinguishing at the most basic level quantitative, qualitative, and mixed …


Integration Of Analysis And Deliberation To Evaluate Biodiesel Occupational And Environmental Exposures, Nora M. Traviss Jan 2008

Integration Of Analysis And Deliberation To Evaluate Biodiesel Occupational And Environmental Exposures, Nora M. Traviss

Antioch University Dissertations & Theses

Many U.S. organizations interested in a renewable and domestic source of energy are considering switching from petroleum diesel to biodiesel blends for transportation and heavy-duty equipment use. Biodiesel is a fuel made from vegetable oils or waste grease. While there is a considerable body of evidence on the negative health effects of petroleum diesel exhaust exposures in occupational and urban settings, there has been little research examining the impact of biodiesel fuel on occupational and environmental exposures. This dissertation combined a collaborative exposure assessment of B20 (20% soy-based biodiesel/80% diesel) at a rural recycling center with a policy intervention to …


The Functions Of Standing, Heather Elliott Jan 2008

The Functions Of Standing, Heather Elliott

Articles

The doctrine of standing is said to be key to vindicating the separation of powers guaranteed by the structure of the Constitution But separation of powers is not monolithic and the Supreme Court has used standing doctrine to promote at least three separationofpowers functions for the courts 1 hearing only cases possessing sufficient concrete adversity to make them susceptible of judicial resolution 2 avoiding questions better answered by the political branches and 3 resisting Congresss use of citizen suits and therefore Congresss conscription of the courts to monitor the compliance of the executive branch with the lawWhatever the value of …


Improving Community Water Conservation Behavior In Chachoengsao, Thailand, Kuakul Sathapornvajana Jan 2008

Improving Community Water Conservation Behavior In Chachoengsao, Thailand, Kuakul Sathapornvajana

Theses: Doctorates and Masters

The issue of water supply throughout the world is of concern for many reasons. It is projected that by the year 2025 two-thirds of the world's population will encounter moderate to severe water shortages. As a result of unsustainable development over the past decade, Thailand has faced pollution problems as well as the depletion of many natural resources. These problems have impacted on the country's main rivers (Chaopraya River, Thachine River, and the Bangpakong River), that are crucial to a sustainable economy, society, and culture. There needs to be a concentrated effort at all levels (individual to community) to address …


Customary Marine Tenure And Traditional Ecological Knowledge In Palau, Robin Putney Jan 2008

Customary Marine Tenure And Traditional Ecological Knowledge In Palau, Robin Putney

Master's Theses

No abstract provided.