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Use Of Positron Annihilation Spectroscopy For Stress-Strain Measurements, Ajit K. Roy

Transmutation Sciences Materials (TRP)

The purpose of this collaborative research project involving the University of Nevada, Las Vegas (UNLV) and Idaho State University (ISU) is to evaluate the feasibility of determining residual stresses of welded (after pre-straining) engineering materials using a new nondestructive technique based on positron annihilation spectroscopy. The proposed technique is to use γ-rays 2 from a small MeV electron Linac to generate positrons inside the sample via pair production. This method can be used for materials characterization and investigation of defects in thick samples that could not be accomplished by conventional positron techniques or other nondestructive methods. The data generated will …

An Economic Analysis Of The Arsenic Standard On Nevada, Jill S. Dale

UNLV Theses, Dissertations, Professional Papers, and Capstones

In 2001, the arsenic standard for drinking water was lowered from 50 parts per billion to 10 parts per billion. The clean-up costs for Nevada are estimated at approximately 400 million dollars. The purpose of this project is to examine the economic impacts the State of Nevada will absorb as a result of the new regulation. Research of historical data will be the basis for the project. National data from the U.S. Environmental Protection Agency and data collected from the State of Nevada will be accompanied by comparable research data found through other sources

The Impact Of The Winter's Doctrine On Water Allocation To The Gila River Indian Community, Deana P. Benally

UNLV Theses, Dissertations, Professional Papers, and Capstones

Can the Gila River Indian Community rely upon the Winter's Doctrine (1908) to obtain more water than the past? The purpose of this thesis is to examine the impact of the Winter's Doctrine on the Gila River Indian Community (GRIC). This research paper uses the case study method to evaluate the relevance of the Winter's Doctrine on current negotiations. Results indicate that the Winter's Doctrine is not expected to have much of an impact on current negotiations with the U.S. Congress.

Constraints On Ground Motion At Yucca Mountain Provided By Precarious Rocks, Abdolrasool Anebshehpoor, James N. Brune, David Von Seggern, Kenneth D. Smith, Amy J. Smiecinski

Publications (YM)

This report describes the methodology and results of the use of precariously balanced rocks to study seismic hazard at Yucca Mountain, Nevada, the site of a potential geologic repository for high-level radioactive waste. Precarious rocks are effectively strong-motion seismoscopes that have been in for place thousands of years. Numerous precarious rocks exist in and near Solitario Canyon, Nevada, immediately above the site of the potential repository. Estimates of toppling accelerations using computer models, physical models, and field tests indicate these rocks would be toppled by ground acceleration of a few tenths of the acceleration of gravity (g). Rock-surface age dating …

Inside Unlv, Diane Russell, Cate Weeks, Tom Flagg

Inside UNLV

No abstract provided.

Coastal Resort Development And Impacts On Shallow Water Aquifers In Southern Baja California, Sur. Mexico, Bud J. Bennenman

UNLV Theses, Dissertations, Professional Papers, and Capstones

A Coastal resort named Fiesta Surf is being planned for the southern portion of the Baja peninsula on the Pacific coast between the resort town of Cabo San Lucas and Todos Santos. Two additional resorts and an exclusive housing community are in the planning stages within this region, known as the "Pacific Corridor." The proposal for development is in a high growth region near the southern tip of the Baja peninsula in the state of Baja California, Sur, Mexico. The Pacific coast of southern Baja has seen little development and consists largely of non-developed shoreline. The current economic base of …

University Of Nevada, Las Vegas Advanced Accelerator Applications University Participation Program: Quarterly Report Fourth Quarter (December 2001 To February 2002), Anthony Hechanova

Transmutation Research Program Reports (TRP)

This Quarterly Report is a primary deliverable from the University of Nevada, Las Vegas (UNLV) Advanced Accelerator Applications (AAA) University Participation Program (UPP) Director to the U.S. Department of Energy (DOE) as described in the UNLV AAA proposal and Statement of Work for the Fourth Quarter.

The UNLV AAA UPP Director implements the program’s administration using staff from the Harry Reid Center for Environmental Studies (HRC) to ensure that work conducted under the UNLV AAA UPP meets program objectives. The UNLV AAA program consists of three components: Program Support, Research Infrastructure Augmentation, and Student Research.

Environment-Induced Degradation And Crack-Growth Studies Of Candidate Target Materials: Aaa Task-4 Quarterly (December 1, 2001 – February 28, 2002) Report, Ajit K. Roy, Brendan O'Toole

Transmutation Sciences Materials (TRP)

The primary objective of this task is to evaluate the effect of hydrogen on environment-assisted cracking of candidate materials for applications in spallation-neutron-target (SNT) systems such as accelerator production of tritium (APT) and accelerator transmutation of waste (ATW). The materials selected for evaluation and characterization are martensitic stainless steels including HT- 9, EP 823 and 422. The susceptibility to stress corrosion cracking (SCC) and hydrogen embrittlement (HE) of these alloys will be evaluated in environments of interest using tensile specimens under constant load and slow-strain-rate (SSR) conditions. The extent and morphology of cracking of these alloys will further be evaluated …

Development Of A Mechanistic Understanding Of High-Temperature Deformation Of Alloy Ep-823: Aaa Task-10 Quarterly (12/1, 2001 –02/28, 2002) Report, Ajit K. Roy, Brendan O'Toole

Transmutation Sciences Materials (TRP)

The objective of this task is to evaluate the elevated temperature tensile properties of Alloy EP-823, a leading target material for accelerator-driven waste transmutation applications. The test material will be thermally treated prior to evaluation of its tensile properties at temperatures relevant to the transmutation applications. The deformation characteristics of tensile specimens, upon completion of testing, will be evaluated by surface analytical techniques including scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The overall results are expected to provide a mechanistic understanding of high-temperature deformation behavior of Alloy EP-823 as a function of heat treatment.

Highlights of Accomplishment

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Third Quarter Report, Covering January Through March 2002, John Farley

Transmutation Sciences Materials (TRP)

Progress from June 2001-November 2001 was presented at the winter meeting of the American Nuclear Society in Reno (November 12-15, 2001), and incorporated into a refereed conference proceeding. A copy of the refereed conference proceeding has been provided to Tony Hechanova. In brief, the paper described the new program to examine the corrosive effects of lead-bismuth eutectic (LBE) on steels. We employed various types of surface studies (Scanning Electron Microscope [SEM], and X-ray Photoelectron Spectrometry [XPS]) to examine steel samples that had been exposed to LBE for various lengths of time at various temperatures. The goal is to understand the …

Inside Unlv, Diane Russell, Betty Blodgett, Kevin Force, Jennifer Vaughan, Cate Weeks, Jonathan Paver

Inside UNLV

No abstract provided.

Design And Evaluation Of Processes For Fuel Fabrication: Quarterly Progress Report #2, Georg F. Mauer

Fuels Campaign (TRP)

The second quarter of the project covered the following:

• Project review with Dr. Mitchell Meyer, ANL West: A project review of the transmuter fuels project was conducted during the January 2002 AAA meeting in Las Vegas.

• A second graduate student, Mr. Richard Silva, began working on the project. Rich will develop detailed 3-D process simulation models as his M.Sc. thesis project. Rich is employed with Bechtel at the Yucca Mountain project.

• AAA Seminar Presentation by Mr. Jae-Kyu Lee and G. Mauer. Title: Transmuter Fuel Fabrication Processes.

• More equipment detail and estimates were developed for different manufacturing …

Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics: Quarterly Progress Report 11/16/01- 2/15/02, Samir Moujaes, Yitung Chen

Transmutation Sciences Materials (TRP)

The Lead-Bismuth eutectic (LBE) has been determined from previous experimental studies by the Russians and the European scientific community to be a potential material that can be used as a spallation target and coolant for the AAA proposed application.

Properly controlling the oxygen content in LBE can drastically reduce the LBE corrosion to structural steels. However, existing knowledge of material corrosion performance was obtained from point-wise testing with very limited density. The transport of oxygen and corrosion products, their interaction and variation of corrosion/precipitation along the flow are not well understood.

The first subtask of this project involves using a …

Development Of A Systems Engineering Model Of The Chemical Separations Process: Quarterly Progress Report 11/16/01- 2/15/02, Yitung Chen, Randy Clarksean, Darrell Pepper

Separations Campaign (TRP)

The AAA program is developing technology for the transmutation of nuclear waste to address many of the long-term disposal issues. An integral part of this program is the proposed chemical separations scheme.

Two activities are proposed in this Phase I task: the development of systems engineering model and the refinement of the Argonne code AMUSE (Argonne Model for Universal Solvent Extraction). The detailed systems engineering model is the start of an integrated approach to the analysis of the materials separations associated with the AAA Program. A second portion of the project is to streamline and improve an integral part of …

Design And Analysis For Melt Casting Metallic Fuel Pins Incorporating Volatile Actinides: Quarterly Progress Report 11/16/01- 2/15/02, Yitung Chen, Randy Clarksean, Darrell Pepper

Fuels Campaign (TRP)

An important aspect of the Advanced Accelerator Applications (AAA) program is the development of a casting process by which volatile actinide element (i.e., americium) can be incorporated into metallic alloy fuel pins. The traditional metal fuel casting process uses an inductively heated crucible.

This process works well for the fabrication of metal fuel pins traditionally composed of alloys of uranium and plutonium, but does not work well when highly volatile actinides are included in the melt. The problem occurs both during the extended time period required to superheat the alloy melt as well as when the chamber must be evacuated. …

Hydrogen-Induced Embrittlement Of Candidate Target Materials For Applications In Spallation-Neutron-Target Systems, Ajit K. Roy, Brendan O'Toole

Transmutation Sciences Materials (TRP)

The purpose of this project is to evaluate the effect of hydrogen on cracking of candidate target materials for applications in spallation-neutron-target (SNT) systems such as accelerator production of tritium (APT) and accelerator transmutation of waste (ATW). The test materials will undergo appropriate thermal treatments prior to being hydrogen-charged by potentiostatic cathodic polarization technique in a simulated aqueous environment at different temperatures of interest. The specimens, upon completion of testing, will be metallographically examined. Further, the scanning electron microscopy (SEM) will be used to determine the extent and nature of cracking in the specimens tested. The thrust of the proposed …

Inside Unlv, Diane Russell, Betty Blodgett, Richard Jensen, Cate Weeks

Inside UNLV

No abstract provided.

Rana Catesbeiana Diet, Chad L. Cross, Shawn Gerstenberger

Environmental & Global Health Faculty Research

Data were obtained opportunistically from 28 adult (14M; 14 F) bullfrogs collected during April 2001 from Meadow Valley Wash located between the cities of Carp and Elgin, Lincoln County. Nevada, USA (37⁰17’N, 114⁰30'W). Although there are two summary reports that provide publication lists of bullfrog food/diet literature (Bury and Whelan I 984. Ecology and Management of the Bullfrog. USDI, FWS Resource Publ. 155. 23 pp.; Casper and Hendricks, in press. In M.J. Lannoo [ed.], Status and Conservation of U.S. Amphibians. Univ. California Press, Berkeley), there are, to our knowledge, no published bullfrog diets from this region.

Biological Reduction Of Perchlorate In Ion Exchange Regenerant Solutions Containing High Salinity And Ammonium Levels, Tina M. Gingras, Jacimaria R. Batista

Civil and Environmental Engineering and Construction Faculty Research

The most promising technologies to remove perchlorate from water are ion exchange and biological reduction. Although successful, ion exchange only separates perchlorate from water; it does not eliminate it from the environment. The waste streams from these systems contain the caustic or saline regenerant solutions used in the process as well as high levels of perchlorate. Biological reduction could be used to treat the regenerant waste solutions from the ion exchange process. A treatment scheme, combining ion exchange and biodegradation, is proposed to completely remove perchlorate from the environment. Perchlorate-laden resins generate brines containing salt concentrations up to 6% or …

Loop Detection And Prevention Mechanism In Multiprotocol Label Switching, Vasu Jolly

UNLV Retrospective Theses & Dissertations

The extended color thread algorithm is based on running a thread hop by hop before the labels are distributed inside a MPLS Cloud Since the path for the data packets is set beforehand, the loop formation occurs at the control path. The shortest paths between selected source and destination have been calculated using Dijkstra's shortest path algorithm and threads are allowed to extend through the routers. With the passage of each next hop, a distributed procedure is executed within the thread, generating a unique color at nodes. This keeps a track on router's control path and at the same time …

Pursuit Evasion: The Herding Noncooperative Dynamic Game-The Stochastic Model, Pushkin Kachroo, Samy A. Shedied, H. Vanlandingham

Electrical & Computer Engineering Faculty Research

This article proposes a solution to the herding problem, a class of pursuit evasion problem in a stochastic framework. The problem involves a "pursuer" agent trying to herd a stochastically moving "evader" agent into a pen. The problem is stated in terms of allowable sequential actions of the two agents. The solution is obtained by applying the principles of stochastic dynamic programming. Three algorithms for solution are presented with their accompanying results.

Exploring The Limits Of The Dipole Approximation With Angle-Resolved Electron Time-Of-Flight Spectrometry, Sierra Laidman, Monica Pangilinan, Renaud Guillemin, Sung Woo Yu, Gunnar Ohrwall, Dennis W. Lindle, Oliver Hemmers

Environmental Studies Faculty Publications

Understanding the electronic structure of atoms and molecules is fundamental in determining their basic properties as well as the interactions that occur with different particles such as light. One such interaction is single photoionization; a process in which a photon collides with an atom or molecule and an electron with a certain kinetic energy is emitted, leaving behind a residual ion. Theoretical models of electronic structures use the dipole approximation to simplify x-ray interactions by assuming that the electromagnetic field of the radiation, expressed as a Taylor-series expansion, can be simplified by using only the first term. It has been …

Determination Of Mass Excavation Haul Distance And Direction By Linear Optimization, Donald Scott Myers

UNLV Retrospective Theses & Dissertations

This thesis develops a two-dimensional grid system for the determination of the haul distance and direction to haul the soil on a mass excavation project using linear optimization programming methodology. The system generates a mathematical solution for the minimum haul distance and the direction in which to haul the soil for each unit of the program grid when formulated with the proper input. The necessary inputs are the calculated cut and fill quantities for each cell of an X-Y coordinate grid system. The mathematical outputs from the cut and fill inputs are converted into a vector drawing indicating the quantity …

The Effect Of Mechanical Vibration On Acute Power Output In The Bench Press, Brach John Poston

UNLV Retrospective Theses & Dissertations

The purpose of this study was to investigate the effect of mechanical vibration on acute power output in the bench press. A total of 10 male subjects performed 3 sets of 3 reps of bench presses using a load equal to 70% one repetition maximum (1RM) on two occasions separated by 3 days. One occasion served as the experimental (vibration) condition while the other occasion served as the control (non-vibration) condition. The conditions differed due to a 30 second vibration stimulation period between bench press sets 2 and 3 in the experimental condition. The control condition incorporated a 30 second …

Southern Nevada Interagency Science & Research Program, Public Lands Institute

Interagency Science and Research Strategy

Conduct and support high quality, relevant, up-to-date research that is needed to solve problems and make effective decisions to enhance conservation, restoration, and adaptive management of public lands.

Spatial And Temporal Patterns Of Eastern White Pine Regeneration In The Northwestern Ohio Oak Stand, Scott R. Abella, Neil W. Macdonald

Public Policy and Leadership Faculty Research

Eastern white pine (Pinus strobus L.) was often associated with oaks (Quercus spp.) on upland sites in presettlement forests of the upper Great Lakes region, but widespread logging and subsequent fires in the late 1800s converted these upland sites to fire-tolerant oak forests. Although white pine regeneration is occurring in these second-growth oak forests, white pine regeneration patterns in oak forests of the Great Lakes region are not well documented. We examined white pine regeneration in the southern Great Lakes region in an oak stand within the Oak Openings region of northwestern Ohio, where white pine plantations established in the …

Bonytail (Gila Elegans) May Enhance Survival Of Razorback Suckers (Xyrauchen Texanus) In Rearing Ponds By Preying On Exotic Crayfish, Nathan Lenon, Krystyna Anne Stave, Tom Burke, James E. Deacon

Public Policy and Leadership Faculty Research

This study examined the potential of bonytail (Gila elegans) to enhance survival of young razorback sucker (Xyrauchen texanus) in rearing ponds by serving as a biological control agent for young stages of Red Swamp Crayfish (Procambarus clarki). Large populations of crayfish in rearing ponds negatively affect the survival of razorback suckers, through predation and competition for food. Traps made with 6.34 mm (0.25 inch) mesh have been used in an effort to reduce crayfish populations, however crayfish less than 17 mm carapace length (CPL) are able to escape. Juvenile bonytail in experimental trials ate young crayfish ranging in size from …

Unlv College Of Education Multicultural & Diversity Newsletter, Porter Troutman, Nancy P. Gallavan, John Filler, Steven Grubaugh, Jennifer L. Fabbi, Kyle Higgins, Aimee Govett, Jean Henry, Lisa Bendixen, Cecilia Maldonado-Daniels, Nancy Sileo

College of Education Multicultural & Diversity Newsletter

A newsletter discussing a variety of topics dealing with multicultural topics and diversity in education.

Unlv College Of Education Multicultural & Diversity Newsletter, Porter Troutman, Nancy P. Gallavan, John Filler, Steven Grubaugh, Jennifer L. Fabbi, Kyle Higgins, Aimee Govett, Jean Henry, Lisa Bendixen, Cecilia Maldonado-Daniels, Nancy Sileo

College of Education Multicultural & Diversity Newsletter

A newsletter discussing a variety of topics dealing with multicultural topics and diversity in education.

Project Continuation Proposal: Radiation Transport Modeling Of Beam-Target Experiments For The Aaa Project, William Culbreth

Reactor Campaign (TRP)

The AAA program will rely on the use of an accelerator-based transmuter1 to expose spent nuclear fuel to high-energy neutrons. The neutron flux will be sufficient to activate or fission the long-lived isotopes of Tc, I, Pu, Am, Cm, and Np that present a significant radiological hazard in commercial spent fuel. Transmuter fuel will be subcritical and a high-energy proton accelerator is needed to maintain the necessary neutron flux through the use of a neutron spallation target. The maximum neutron energy produced by spallation (~ 800 MeV) is significantly higher than that produced by a commercial light water reactor (~ …