Resource Type

Monitoring Plan for RCRA Groundwater Assessment at the 216-U-12 Crib, Interim Change Notice 1 (open access)

Monitoring Plan for RCRA Groundwater Assessment at the 216-U-12 Crib, Interim Change Notice 1

This ICN corrects a typing error that was identified for one of the wells listed in Tables 4.1 and 4.2 on page 4.3 of the original document.
Date: November 25, 2003
Creator: Williams, Bruce A.
System: The UNT Digital Library
Near-Field Hydrology Data Package for the Integrated Disposal Facility 2005 Performance Assessment (open access)

Near-Field Hydrology Data Package for the Integrated Disposal Facility 2005 Performance Assessment

CH2MHill Hanford Group, Inc. (CHG) is designing and assessing the performance of an Integrated Disposal Facility (IDF) to receive immobilized low-activity waste (ILAW), Low-Level and Mixed Low-Level Wastes (LLW/MLLW), and the Waste Treatment Plant (WTP) melters used to vitrify the ILAW. The IDF Performance Assessment (PA) assesses the performance of the disposal facility to provide a reasonable expectation that the disposal of the waste is protective of the general public, groundwater resources, air resources, surface water resources, and inadvertent intruders. The PA requires prediction of contaminant migration from the facilities, which is expected to occur primarily via the movement of water through the facilities and the consequent transport of dissolved contaminants in the pore water of the vadose zone. Pacific Northwest National Laboratory (PNNL) assists CHG in its performance assessment activities. One of PNNL’s tasks is to provide estimates of the physical, hydraulic, and transport properties of the materials comprising the disposal facilities and the disturbed region around them. These materials are referred to as the near-field materials. Their properties are expressed as parameters of constitutive models used in simulations of subsurface flow and transport. In addition to the best-estimate parameter values, information on uncertainty in the parameter values and …
Date: June 25, 2004
Creator: Meyer, Philip D.; Saripalli, Prasad & Freedman, Vicky L.
System: The UNT Digital Library
KDP Impurity Data (open access)

KDP Impurity Data

Attached are the impurity data for 20-liter growth runs N. Zaitseva/L. Carman made in the 1996-1997 time frame for which we have both solution and crystal data. The 5 impurities added for the runs are AI(III), Cr(III), Fe(III), Mo(VI), and Sb(V). As an explanation of the tables, I report all impurity concentrations as ppb (ng/g{sub KDP}) with respect to dry KDP (even solution data.) ''MDL'' stands for ''Method Detection Limit.'' Nominal uncertainties are 1 MDL or 10% of the quoted value, whichever is greater. If the measured value is less than the MDL, I report ''ND,'' for ''Not Detected.'' If the value is greater than the MDL, but less than twice the MDL, I report ''D,'' for ''Detected.'' If the value is more than twice the MDL, I report two significant figures. The values come from ICP-ES and ICP-MS measurements. I give the detection limit for the more sensitive technique in the table under the ''MDL'' heading. In case where only one technique was used, I give the MDL for that technique in parentheses after the impurity value in the table. Since these measurements were made, changes in instrumentation have resulted in significant improvements in many of the detection limits. …
Date: October 25, 2001
Creator: Torres, R A
System: The UNT Digital Library
Chord Distributions of a Spherical Shell (open access)

Chord Distributions of a Spherical Shell

None
Date: June 25, 2004
Creator: Chang, B.
System: The UNT Digital Library
Science & Technology Review March 2005 (open access)

Science & Technology Review March 2005

This issue of Science and Technology Review has the following articles: (1) Enhanced National Security through International Research Collaborations--Commentary by Stephen G. Cochran; (2) Building Networks of Trust through Collaborative Science--Livermore scientists are leading collaborative science and technology projects with colleagues from Central and South Asia and the Middle East; (3) Tracing the Steps in Nuclear Material Trafficking--The Laboratory.s nuclear science expertise is helping to thwart the illicit trafficking of nuclear material; (4) Looking at Earth in Action--Geophysicists at Livermore are using laboratory experiments to examine such issues as how best to store nuclear wastes and how to mitigate the effects of greenhouse gases; and (5) Gamma-Ray Bursts Shower the Universe with Metals--Computer models indicate that gamma-ray bursts from dying stars may be important sources of elements such as iron, zinc, titanium, and copper.
Date: January 25, 2005
Creator: Henson, V E
System: The UNT Digital Library
Radiochemical Assays of Irradiated VVER-440 Fuel for Use in Spent Fuel Burnup Credit Activities (open access)

Radiochemical Assays of Irradiated VVER-440 Fuel for Use in Spent Fuel Burnup Credit Activities

The objective of this spent fuel burnup credit work was to study and describe a VVER-440 reactor spent fuel assembly (FA) initial state before irradiation, its operational irradiation history and the resulting radionuclide distribution in the fuel assembly after irradiation. This work includes the following stages: (1) to pick out and select a specific spent (irradiated) FA for examination; (2) to describe the FA initial state before irradiation; (3) to describe the irradiation history, including thermal calculations; (4) to examine the burnup distribution of select radionuclides along the FA height and cross-section; (5) to examine the radionuclide distributions; (6) to determine the Kr-85 release into the plenum; (7) to select and prepare FA rod specimens for destructive examinations; (8) to determine the radionuclide compositions, isotope masses and burnup in the rod specimens; and (9) to analyze, document and process the results. The specific workscope included the destructive assay (DA) of spent fuel assembly rod segments with an {approx}38.5 MWd/KgU burnup from a single VVER-440 fuel assembly from the Novovorenezh reactor in Russia. Based on irradiation history criteria, four rods from the fuel assembly were selected and removed from the assembly for examination. Next, 8 sections were cut from the four …
Date: April 25, 2005
Creator: Jardine, L J
System: The UNT Digital Library
Data Package for Groundwater Monitoring Well 299-W15-43 at the 200-ZP-1 Operable Unit (open access)

Data Package for Groundwater Monitoring Well 299-W15-43 at the 200-ZP-1 Operable Unit

One new groundwater monitoring well was constructed at the 200-ZP-1 Operable Unit in November 2002. This document provides the information on drilling and construction of this well. One new groundwater monitoring well was constructed in the 200-ZP-1 Operable Unit in November 2002. The purpose of the well is to monitor carbon tetrachloride concentrations in response to the 200-ZP-1 carbon tetrachloride pump-and-treat operations. The well name is 299-W15-43 and the corresponding well number is C3955. Well 299-W15-43 is located about 8 meters west of the 216-T-25 trench. The location of the well is shown on Figure 1. Well 299-W15-43 was drilled in response to the recommendations of a Data Quality Objectives process that indicated a need for additional monitoring wells in the area (BHI-01576). The new well was constructed to the specifications and requirements described in Washington Administrative Code (WAC) 173-160 and WAC 173-303, the Data Quality Objectives document (BHI-01576), and the description of work for well drilling and construction. This document compiles information on the drilling and construction, geophysical logging, and sediment and groundwater sampling applicable to the installation of well 299-W15-43. The information on drilling and construction, well development, and pump installation is summarized from CP-14265. Appendix A contains …
Date: April 25, 2003
Creator: Horton, Duane G.
System: The UNT Digital Library
Cold Dissolved Saltcake Waste Simulant Development, Preparation, and Analysis (open access)

Cold Dissolved Saltcake Waste Simulant Development, Preparation, and Analysis

CH2M Hill Hanford Group, Inc. is identifying and developing supplemental process technologies to accelerate the Hanford tank waste cleanup mission. Bulk vitrification, containerized grout, and steam reforming are three technologies under consideration for treatment of the radioactive saltcake wastes in 68 single-shell tanks. To support development and testing of these technologies, Pacific Northwest National Laboratory (PNNL) was tasked with developing a cold dissolved saltcake simulant formulation to be representative of an actual saltcake waste stream, preparing a 25-L batch of the simulant, and analyzing the composition of the batch to assure conformance to formulation targets. Lacking a defined composition for dissolved actual saltcake waste, PNNL used available tank waste composition information and an equilibrium chemistry model (Environmental Simulation Program, ESP) to predict the concentrations of analytes in solution. Observations of insoluble solids in initial laboratory preparations for the model predicted formulation prompted minor modifications in the concentration of phosphate and silicon in the final simulant formulation. The analytical results for the 25-L simulant batch agree within the expected measurement accuracy (~10%) of the target concentrations and are highly consistent for replicate measurements, with a few minor exceptions. The instrumental analyses indicate that the batch of solution adequately reflects the as-formulated …
Date: February 25, 2003
Creator: Rassat, Scot D.; Mahoney, Lenna A.; Russell, Renee L.; Bryan, Samuel A. & Sell, Rachel L.
System: The UNT Digital Library
Slow-Growing Subdivisions in any Dimension: Towards Removing the Curse of Dimensionality (open access)

Slow-Growing Subdivisions in any Dimension: Towards Removing the Curse of Dimensionality

The efficient representation of volumetric meshes is a central problem in scientific visualization. The difference in performance between most visualization algorithm for rectilinear grids and for unstructured mesh is mostly due to fundamental difference in efficiency of their representations. In Computer Graphics the gap in performance between 2D rectilinear grids and unstructured mesh has been overcome with the development of representation schemes based on the concept of subdivision surfaces. This gap has not been bridged in the volumetric cases which is fundamental interest for Scientific Visualization. In this paper we introduce a slow-growing volumetric subdivision scheme for meshes of any topology, any intrinsic dimension d and composed of a general type of polyhedral cells (topological balls). The main feature of this approach is the ability to split in different stages cells of different dimensions. This allows to increase the resolution of the mesh slowly using small stencils for the smoothing rules. ''Sharp features'' of dimension lower than d are embedded naturally in the subdivision procedure. Automatic adaptation is provided for variable resolution. In the uniform case the slow subdivision doubles the number of vertices in the mesh at each refinement independent of its dimension d. The bisection of all the …
Date: June 25, 2001
Creator: Pascucci,V
System: The UNT Digital Library
Evaluation of the 239Pu(n,2n) Integrated Cross Section (open access)

Evaluation of the 239Pu(n,2n) Integrated Cross Section

Recently, new cross section measurements by the GEANIE collaboration have been published for {sup 239}Pu(n, 2n{gamma}) [Ber00] and {sup 235}U(n, 2n{gamma}) [You00] from threshold to 20 MeV. When combined with nuclear reaction calculations [Che00, Cha99, Cha01], these measurements provide the most accurate information available on the shape and magnitude of the {sup 239}Pu(n, 2n) cross section for incident neutron energies, E{sub n} {approx}< 14 MeV. This new data has prompted a re-evaluation of the {sup 239}Pu(n, 2n) {sup 238}Pu reaction cross section considering all available experimental data. The data prior to the measurement of Bernstein et al. [Ber00] is illustrated in Figure 1a. These data sets were considered by previous evaluations [ENDL] of the {sup 239}Pu(n, 2n) cross section. The most precise experiment was an activation measurement done by Lougheed et al. [Lou00] for incident neutron energies, E{sub n}, between 13-15 MeV. In addition, there were two neutron-counting experiments, one by Mather et al. [Mat72] and one by Frehaut et al. [Fre85]. These two measurements cover a wide incident neutron range, with data points from threshold to E{sub n} {approx} 14 MeV. The available data sets are in poor agreement with each other and in some cases do not meet …
Date: January 25, 2001
Creator: McNabb, D. P.; Anderson, J. D.; Bauer, R. W.; Becker, J. A.; Dietrich, F.; Navratil, P. et al.
System: The UNT Digital Library
Saturation of impurity-rich phases in a cerium-substituted pyrochlore-rich titanate ceramic: part 1 experimental results (open access)

Saturation of impurity-rich phases in a cerium-substituted pyrochlore-rich titanate ceramic: part 1 experimental results

The saturation of impurity-rich accessory phases in a Ce-analog baseline ceramic formulation for the immobilization of excess plutonium has been tested by synthesizing an impurity-rich baseline compositions at 1300 C, 1350 C, and 1400 C in air. Impurity oxides are added at the 10 wt% level. The resulting phases assemblages are typically rich in pyrochlore, Hf-zirconolite (hafnolite), brannerite and rutile, but in many instances also contain an accessory mineral enriched in the impurity oxide. The concentration of that oxide in coexisting pyrochlore sets the saturation limit for solid solution of the component in question. In most cases, the accessory phase does not contain significant amounts of Ce, Gd or U. Exceptions are the stabilization of a Ca-lanthanide phosphate and a phosphate glass when P{sub 2}O{sub 5} is added to the formulation. P{sub 2}O{sub 5} addition is also very effective in reducing the modal amount of pyrochlore in the form relative to brannerite. Addition of the sodium-aluminosilicate, NaAlSiO{sub 4}, also results in the formation of a grain boundary melt at run conditions, but the fate of this phase on cooling is not well determined. At temperatures above 1300 C, addition of 10 wt% Fe{sub 2}O{sub 3} also leads to melting. Substitution …
Date: May 25, 2000
Creator: Ryerson, F. J.; Ebbinghaus, B.; Kirkorian, O. & VanKonynenburg, R.
System: The UNT Digital Library
Application of Prompt Gamma-Ray Analysis to Identify Electrorefining Salt-Bearing Plutonium Oxide at the Plutonium Finishing Plant (open access)

Application of Prompt Gamma-Ray Analysis to Identify Electrorefining Salt-Bearing Plutonium Oxide at the Plutonium Finishing Plant

Prompt gamma-ray analysis is being implemented at the Plutonium Finishing Plant (PFP) to screen impure plutonium oxide inventory items, received in the mid-1980s from the Rocky Flats Plant, for the presence of sodium chloride and potassium chloride salts from the electrorefining process. A large fraction of these items are suspected to contain electrorefining salts. Because the salts evaporate at the=950C stabilization temperature mandated for long-term storage under the U.S. Department of Energy plutonium oxide stabilization and storage criteria to plug and corrode process equipment, items found to have these salts qualify for thermal stabilization at 750C. The prompt gamma ray energies characteristic of sodium, potassium, chlorine, and other low atomic weight elements arise from the interaction the light elements with alpha radiation from plutonium and americium radioactive decay. High-resolution gamma ray spectrometers designed to detect energies up to {approx}4.5 MeV are used to gather the high-energy prompt gamma spectra.Observation of the presence of the high-energy gamma peaks representing the natural chlorine-35, sodium-23, and potassium-39 isotopes and the sodium-to-chlorine peak area ratios in the range for plutonium oxide materials known to contain the electrorefining salts give the evidence needed to identify plutonium oxide materials at the PFP that qualify for the …
Date: September 25, 2003
Creator: Fazzari, Dennis M. (FLUOR HANFORD, INC); Jones, Susan A. (FLUOR HANFORD, INC) & Delegard, Calvin H. (BATTELLE (PACIFIC NW LAB))
System: The UNT Digital Library
National Ignition Facility Cryogenic Target Systems Interim Management Plan (open access)

National Ignition Facility Cryogenic Target Systems Interim Management Plan

Restricted availability of funding has had an adverse impact, unforeseen at the time of the original decision to projectize the National Ignition Facility (NIF) Cryogenic Target Handling Systems (NCTS) Program, on the planning and initiation of these efforts. The purpose of this document is to provide an interim project management plan describing the organizational structure and management processes currently in place for NCTS. Preparation of a Program Execution Plan (PEP) for NCTS has been initiated, and a current draft is provided as Attachment 1 to this document. The National Ignition Facility is a multi-megajoule laser facility being constructed at Lawrence Livermore National Laboratory (LLNL) by the National Nuclear Security Administration (NNSA) in the Department of Energy (DOE). Its primary mission is to support the Stockpile Stewardship Program (SSP) by performing experiments studying weapons physics, including fusion ignition. NIF also supports the missions of weapons effects, inertial fusion energy, and basic science in high-energy-density physics. NIF will be operated by LLNL under contract to the University of California (UC) as a national user facility. NIF is a low-hazard, radiological facility, and its operation will meet all applicable federal, state, and local Environmental Safety & Health (ES&H) requirements. The NCTS Interim Management …
Date: April 25, 2002
Creator: Warner, B
System: The UNT Digital Library
Possible Incorporation of Neptunium in Uranyl (VI) Alteration Phases (open access)

Possible Incorporation of Neptunium in Uranyl (VI) Alteration Phases

This study examines existing data on Np behavior from both spent fuel and borosilicate glass tests in effort to resolve issues concerning the selection of possible solubility limiting phases for neptunium and the methods for detecting neptunium at low levels in spent fuel. These issues were raised in a recent report by Finch and Fortner (2002) that argues that the Np analysis with Electron Energy-Loss Spectroscopy (EELS) reported by Buck et al., (1998) is incorrect and that based on a series of experiments with Np-doped U3O8, NpO2 should be adopted as the solubility controlling phase for Np, in the Yucca Mountain performance assessment model. In this report, we will refute the claim that EELS is unable to detect Np and will suggest that the use of NpO2 as the Np solubility controlling phase is not supported by available scientific data from both spent fuel and borosilicate glass.
Date: November 25, 2003
Creator: Buck, Edgar C.; McNamara, Bruce K.; Douglas, Matthew & Hanson, Brady D.
System: The UNT Digital Library
Pyrochlore-rich titanate ceramics for the immobilization of plutonium: redox effects on phase equilibria in cerium- and thorium- substituted analogs (open access)

Pyrochlore-rich titanate ceramics for the immobilization of plutonium: redox effects on phase equilibria in cerium- and thorium- substituted analogs

Three compositions representing plutonium-free analogs of a proposed Ca-Ti-Gd-Hf-U-PU oxide ceramic for the immobilization of plutonium were equilibrated at 1 atm, 1350 C over a range of oxygen fugacities between air and that equivalent to the iron-wuestite buffer. The cerium analog replaces Pu on a mole-per-mole basic with Ce; the thorium analog replaces Pu with Th. A third material has 10 wt% Al{sub 2}O{sub 3} added to the cerium analog to encourage the formation of a Hf-analog of, CaHfTi{sub 2}O{sub 7}, zirconolite, which is referred to as hafnolite. The predominant phase produced in each formulation under all conditions is pyrochlore, A{sub 2}T{sub 2}O{sub 7}, where the T site is filled by Ti, and Ca, the lanthanides, Hf, U and Pu are accommodated on the A-site. Other lanthanide and uranium-bearing phases encountered include brannerite (UTi{sub 2}O{sub 6}), hafnolite (CaHfTi{sub 2}O{sub 7}), perovskite (CaTiO{sub 3}) and a calcium-lanthanide aluminotitanate with nominal stoichiometry (Ca,Ln)Ti{sub 2}Al{sub 9}O{sub 19}, where Ln is a lanthanide. The phase compositions show progressive shifts with decreasing oxygen fugacity. All of the phases observed have previously been identified in titanate-based high-level radioactive waste ceramics and demonstrate the flexibility of these ceramics to variations in processing parameters. The main variation is …
Date: May 25, 2000
Creator: Ryerson, F. J. & Ebbinghaus, B.
System: The UNT Digital Library
Groundwater Monitoring Plan for the 216-S-10 Pond and Ditch, Interim Change Notice 1 (open access)

Groundwater Monitoring Plan for the 216-S-10 Pond and Ditch, Interim Change Notice 1

During 2003, the upgradient well 299-W26-7 went dry and one new groundwater monitoring well was installed downgradient (well 299-W26-14) of the 216-S-10 pond and ditch. This ICN updates the groundwater monitoring wells for the 216-S-10 pond and ditch and adds a revised well location map to the plan.
Date: November 25, 2003
Creator: Williams, Bruce A.
System: The UNT Digital Library
Candidate Reagents for Dissolution of Hanford Site Tank Sludges-Scoping Studies with Simulants Using Single Reagents and Their Mixtures (open access)

Candidate Reagents for Dissolution of Hanford Site Tank Sludges-Scoping Studies with Simulants Using Single Reagents and Their Mixtures

Chemical agents were investigated for their efficacies in dissolving metal compound phases known to be present in Hanford tank waste sludges. The phases included Fe(OH)3, Cr(OH)3, Al(OH)3, MnO2, and Na2U2O7. In conjunction with laboratory testing, a survey of the technical literature also was performed to identify candidate reagents. The tests were conducted in three campaigns. First, scoping tests investigated individual agents identified in the literature review along with other candidate agents. Based on the scoping test results, follow-up testing was performed to investigate the efficacies of mixed citric/oxalic acids (CITROX) and mixed nitric/oxalic acids (NITROX). Overall, oxalic acid is the most effective single reagent, dissolving all of the solid phases to some extent. However, for MnO2 and Na2U2O7, reprecipitation soon followed dissolution. The MnO2 also oxidized at least two of organic acids tested, oxalic acid and citric acid, as shown by the evolution of gas during the tests with these reagents. The CITROX and NITROX tests failed to show beneficial synergistic effects in dissolving sludge phases. Instead, the findings suggest that the sequential addition of individual pure reagents (e.g., first citric acid to dissolve MnO2 and Na2U2O7 and removal of the solution followed by oxalic acid to dissolve the Fe, …
Date: August 25, 2003
Creator: Sinkov, Serguei I.
System: The UNT Digital Library
Interim Status Groundwater Monitoring Plan for Low-Level Waste Management Areas 1 to 4, RCRA Facilities, Hanford,Washington (open access)

Interim Status Groundwater Monitoring Plan for Low-Level Waste Management Areas 1 to 4, RCRA Facilities, Hanford,Washington

This document describes the monitoring plan to meet the requirements for interim status groundwater monitoring at Hanford Site low-level waste burial grounds as specified by 40 CFR 265, incorporated by reference in WAC 173-303-400. The monitoring will take place at four separate low-level waste management areas in the 200-West and 200-East Areas, in the central part of the site. This plan replaces the previous monitoring plan.
Date: October 25, 2004
Creator: Dresel, P Evan
System: The UNT Digital Library
Historical Sulfur Dioxide Emissions 1850-2000: Methods and Results (open access)

Historical Sulfur Dioxide Emissions 1850-2000: Methods and Results

A global, self-consistent estimate of sulfur dioxide emissions over the last one and a half century were estimated by using a combination of bottom-up and best available inventory methods including all anthropogenic sources. We find that global sulfur dioxide emissions peaked about 1980 and have generally declined since this time. Emissions were extrapolated to a 1{sup o} x 1{sup o} grid for the time period 1850-2000 at annual resolution with two emission height levels and by season. Emissions are somewhat higher in the recent past in this new work as compared with some comprehensive estimates. This difference is largely due to our use of emissions factors that vary with time to account for sulfur removals from fossil fuels and industrial smelting processes.
Date: January 25, 2004
Creator: Smith, Steven J.; Andres, Robert; Conception , Elvira & Lurz, Joshua
System: The UNT Digital Library
Impulse Response Estimation for Spatial Resolution Enhancement in Ultrasonic NDE Imaging (open access)

Impulse Response Estimation for Spatial Resolution Enhancement in Ultrasonic NDE Imaging

This report describes a signal processing algorithm and MATLAB software for improving spatial resolution in ultrasonic nondestructive evaluation (NDE) imaging of materials. Given a measured reflection signal and an associated reference signal, the algorithm produces an optimal least-squares estimate of the impulse response of the material under test. This estimated impulse response, when used in place of the raw reflection signal, enhances the spatial resolution of the ultrasonic measurements by removing distortion caused by the limited-bandwidth transducers and the materials under test. The theory behind the processing algorithms is briefly presented, while the reader is referred to the bibliography for details. The main focus of the report is to describe how to use the MATLAB software. Two processing examples using actual ultrasonic measurements are provided for tutorial purposes.
Date: June 25, 2004
Creator: Clark, G A
System: The UNT Digital Library
Ultrasonic Examination of Double-Shell Tank 241-SY-101. Examination Completed March 2004. (open access)

Ultrasonic Examination of Double-Shell Tank 241-SY-101. Examination Completed March 2004.

COGEMA Engineering Corporation (COGEMA), under a contract from CH2M Hill Hanford Group (CH2M Hill), has performed an ultrasonic nondestructive examination of selected portions of Double-Shell Tank 241-SY-101. The purpose of this examination was to provide information that could be used to evaluate the integrity of the wall of the primary tank. The requirements for the ultrasonic examination of Tank 241-SY-101 were to detect, characterize (identify, size, and locate), and record measurements made of any wall thinning, pitting, or cracks that might be present in the wall of the primary tank. Any measurements that exceed the requirements set forth in the Engineering Task Plan (ETP), RPP-17750 (Jensen 2003) and summarized on page 1 of this document, are reported to CH2M Hill and the Pacific Northwest National Laboratory (PNNL) for further evaluation. Under the contract with CH2M Hill, all data is to be recorded on disk and paper copies of all measurements are provided to PNNL for third-party evaluation. PNNL is responsible for preparing a report that describes the results of the COGEMA ultrasonic examinations.
Date: May 25, 2004
Creator: Pardini, Allan F. & Posakony, Gerald J.
System: The UNT Digital Library
An Analysis of Stream Culvert Fish Passage on the Navy Railroad Line between Bremerton and Shelton, Washington (open access)

An Analysis of Stream Culvert Fish Passage on the Navy Railroad Line between Bremerton and Shelton, Washington

The Navy railroad service line runs between Shelton, Bremerton, and Silverdale, and is used by the Navy to transfer freight to its facilities. It is also used by commercial clients to ship service items and bulk cargo for municipalities along portions of the route. Culverts of various size and construction convey streams and stormwater runoff under the railroad line. These allow transfer of water and, in some cases allow for passage of juvenile and adult salmon into waters upstream of the culverts. As part of this project, 21 culverts along a 34-mile reach (Shelton to Bremerton) of this railroad were surveyed to evaluate their function and ability to allow salmon to utilize the streams. The culverts and attached watersheds were evaluated using criteria developed by the Washington Department of Fish and Wildlife to assign a Priority Index (PI) to barriers present on each fish-bearing stream. The PI is a relative numeric rating indicator, assigned using consistent criteria related to the degree of potential habitat gained by removing barriers and improving the function of the watershed. Of the 21 culverts evaluated, five were found to be complete fish-passage barriers and six were found to be partial barriers, primarily to juvenile salmon. …
Date: October 25, 2004
Creator: May, Christopher W.; Miller, Martin C. & Southard, John A.
System: The UNT Digital Library
Simulation of Time-Reversal Processing for Electromagnetic Communication (open access)

Simulation of Time-Reversal Processing for Electromagnetic Communication

Time-reversal processing was simulated for several possible electromagnetic communication channels, including random point scatterers, large plates and a conducting cavity. Communication was from a single transmitting antenna to a receiving array. The effectiveness of time-reversal processing was compared for a single receiver and the array. The aim of these simulations was to determine a communication environment that would give an interesting level of multipath interference and that can be constructed in a laboratory.
Date: July 25, 2003
Creator: Burke, G J & Poggio, A J
System: The UNT Digital Library
Fundamental nucleon-nucleon interaction: probing exotic nuclear structure using GEANIE at LANCE/WNR (open access)

Fundamental nucleon-nucleon interaction: probing exotic nuclear structure using GEANIE at LANCE/WNR

The initial goal of this project was to study the in-medium nucleon-nucleon interaction by testing the fundamental theory of nuclear structure, the shell model, for nuclei between {sup 8}Zr and {sup 100}Sn. The shell model predicts that nuclei with ''magic'' (2,8,20,28,40,50, and 82) numbers of protons or neutrons form closed shells in the same fashion as noble gas atoms [may49]. A ''doubly magic'' nucleus with a closed shell of both protons and neutrons has an extremely simple structure and is therefore ideal for studying the nucleon-nucleon interaction. The shell model predicts that doubly magic nuclei will be spherical and that they will have large first-excited-state energies ({approx} 1 to 3 MeV). Although the first four doubly-magic nuclei exhibit this behavior, the N = Z = 40 nucleus, {sup 80}Zr, has a very low first-excited-state energy (290 keV) and appears to be highly deformed. This breakdown is attributed to the small size of the shell gap at N = Z = 40. If this description is accurate, then the N = Z = 50 doubly magic nucleus, {sup 100}Sn, will exhibit ''normal'' closed-shell behavior. The unique insight provided by doubly-magic nuclei from {sup 80}Zr to {sup 100}Sn has made them the …
Date: February 25, 2000
Creator: Bernstein, L
System: The UNT Digital Library