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  Partner: UNT Libraries Government Documents Department
 Decade: 1990-1999
Point Defect Incorporation During Diamond Chemical Vapor Deposition
The incorporation of vacancies, H atoms, and sp{sup 2} bond defects into single-crystal homoepitaxial (100)(2x1)- and(111)-oriented CVD diamond was simulated by atomic-scale kinetic Monte Carlo. Simulations were performed for substrate temperatures from 600 C to 1200 C with 0.4% CH{sub 4} in the feed gas, and for 0.4% to 7% CH{sub 4} feeds with a substrate temperature of 800 C. The concentrations of incorporated H atoms increase with increasing substrate temperature and feed gas composition, and sp{sup 2} bond trapping increases with increasing feed gas composition. Vacancy concentrations are low under all conditions. The ratio of growth rate to H atom concentration is highest around 800-900 C, and the growth rate to sp{sup 2} ratio is maximum around 1% CH{sub 4}, suggesting that these conditions are ideal for economical diamond growth under the simulated conditions. digital.library.unt.edu/ark:/67531/metadc794918/
The Management of Silica in Los Alamos National Laboratory Tap Water - A Study of Silica Solubility
Well water at Los Alamos National Laboratory (LANL) has a silica (SiO{sub 2}) content of 60 to 100 mg/L, with 4 mg/L of magnesium, 13 mg/L calcium and lesser concentrations of other ions. On evaporation in cooling towers, when the silica concentration reaches 150 to 220 mg/L, silica deposits on heat transfer surfaces. When the high silica well water is used in the reprocessing of plutonium, silica remains in solution at the end of the process and creates a problem of removal from the effluent prior to discharge or evaporation. The work described in this Report is divided into two major parts. The first part describes the behavior of silica when the water is evaporated at various conditions of pH and in the presence of different classes of anions: inorganic and organic. In the second part of this work it was found that precipitation (floccing) of silica was a function of solution pH and mole ratio of metal to silica. digital.library.unt.edu/ark:/67531/metadc793648/
A conceptual design for an electron beam
This report is a brief description of a model electron beam, which is meant to serve as a pulsed heat source that vaporizes a metal fleck into an ''under-dense'' cloud. See Reference 1. The envelope of the electron beam is calculated from the paraxial ray equation, as stated in Reference 2. The examples shown here are for 5 A, 200 keV beams that focus to waists of under 0.4 mm diameter, within a cylindrical volume of 10 cm radius and length. The magnetic fields assumed in the examples are moderate, 0.11 T and 0.35 T, and can probably be created by permanent magnets. digital.library.unt.edu/ark:/67531/metadc793601/
Activity plan for activity E-20-81: development and experimental validation of crevice corrosion models
Alloy 22 [UNS N06022] is now being considered for construction of high level waste containers to be emplaced at the potential repository at Yucca Mountain or elsewhere. In essence, this alloy is 21% Cr, 13% Mo, 4% Fe, 3% W, 2% Co, with the balance being Ni. Variants without tungsten are also being considered. Detailed mechanistic models are being developed to account for the corrosion of Alloy 22 surfaces in crevices that will inevitably form. Such occluded areas experience substantial decreases in pH, with corresponding elevations in chloride concentration. Other relevant materials will also be investigated: nickel-based alloys such as Alloys 825, 625, C-4, C-276 and 59; titanium-based alloys such as Grades 12, 7 and 16, carbon steels such as A516 Grade 55; stainless steels such as 304, 304L, 316, 316L and 316NG; various copper-based alloys; and any materials that would serve as crevice formers (rock, thermally-sprayed ceramics, etc.). Experimental work has been undertaken to validate the crevice corrosion model, including parallel studies with 304 stainless steel. The crevice corrosion model is described in detail in scientific notebooks of the Principal Investigator, as well as other publications. Codes will be prepared in accordance with the YMP QP entitled ''Software Quality Assurance'' (033-YMP-QP 12.0). digital.library.unt.edu/ark:/67531/metadc793693/
Auxiliary analyses in support of performance assessment of a hypothetical low-level waste facility: Two-phase flow and contaminant transport in unsaturated soils with application to low-level radioactive waste disposal. Volume 2
A numerical model of multiphase air-water flow and contaminant transport in the unsaturated zone is presented. The multiphase flow equations are solved using the two-pressure, mixed form of the equations with a modified Picard linearization of the equations and a finite element spatial approximation. A volatile contaminant is assumed to be transported in either phase, or in both phases simultaneously. The contaminant partitions between phases with an equilibrium distribution given by Henry`s Law or via kinetic mass transfer. The transport equations are solved using a Galerkin finite element method with reduced integration to lump the resultant matrices. The numerical model is applied to published experimental studies to examine the behavior of the air phase and associated contaminant movement under water infiltration. The model is also used to evaluate a hypothetical design for a low-level radioactive waste disposal facility. The model has been developed in both one and two dimensions; documentation and computer codes are available for the one-dimensional flow and transport model. digital.library.unt.edu/ark:/67531/metadc793692/
Fabrication of Test Tubes for Coal Ash Corrosion Testing
This paper deals with the fabrication of tube sections of four alloys for incorporating into test sections to be assembled by Babcock & Wilcox (B&W) for installation at Ohio Edison Power, Niles Plant. The primary purpose of the installation was to determine the corrosion behavior of ten different alloys for flue gas corrosion. Ohio Edison Power, Niles Plant is burning an Ohio coal containing approximately 3.4% S (dry basis) and approximately 0.4% alkali which causes chronic coal ash corrosion of the unit�s superheater tubing. The 2.5-in.-OD x 0.4in.-wall x 6-in-long sections of four alloys {type 304H coated with Fe<sub>3</sub>Al alloy FAS [developed at the Oak Ridge National Laboratory (ORNL)], 310 + Ta, modified 800H, and Thermie alloy} were fabricated at ORNL. Each alloy tubing was characterized in terms of chemical analysis and microstructure. The machined tubes of each of the alloys were inspected and shipped on time for incorporation into the test loop fabricated at B&W. Among the alloys fabricated, Thermie was the hardest to extrude and machine. digital.library.unt.edu/ark:/67531/metadc793614/
Radioisotope yields from 1.85-GeV protons on Mo and 1.85- and 5.0-GeV protons on Te
Radioisotope yields from 1.85-GeV proton interactions in a natural isotopic composition Mo target and those from 1.85- and 5.0-GeV protons in natural Te targets were measured at Lawrence Berkeley Laboratory`s Bevatron. The radioisotope yields were determined by {gamma}-counting the targets using a 100-cm{sup 3} coaxial Ge detector following the irradiations. Cross sections were determined for the production of 31 radioactive nuclides, ranging from Z = 35, A = 74, to Z = 43, A = 97, from the Mo target and for 47 radioactive nuclides, ranging from Z = 35, A = 75, to Z = 53, A = 130 from the Te targets. digital.library.unt.edu/ark:/67531/metadc793628/
Aging of turbine drives for safety-related pumps in nuclear power plants
This study was performed to examine the relationship between time-dependent degradation and current industry practices in the areas of maintenance, surveillance, and operation of steam turbine drives for safety-related pumps. These pumps are located in the Auxiliary Feedwater (AFW) system for pressurized-water reactor plants and in the Reactor Core Isolation Cooling and High-Pressure Coolant Injection systems for boiling-water reactor plants. This research has been conducted by examination of failure data in the Nuclear Plant Reliability Data System, review of Licensee Event Reports, discussion of problems with operating plant personnel, and personal observation. The reported failure data were reviewed to determine the cause of the event and the method of discovery. Based on the research results, attempts have been made to determine the predictability of failures and possible preventive measures that may be implemented. Findings in a recent study of AFW systems indicate that the turbine drive is the single largest contributor to AFW system degradation. However, examination of the data shows that the turbine itself is a reliable piece of equipment with a good service record. Most of the problems documented are the result of problems with the turbine controls and the mechanical overspeed trip mechanism; these apparently stem from three major causes which are discussed in the text. Recent improvements in maintenance practices and procedures, combined with a stabilization of the design, have led to improved performance resulting in a reliable safety-related component. However, these improvements have not been universally implemented. digital.library.unt.edu/ark:/67531/metadc793654/
FINITE-ELEMENT ANALYSIS OF ROCK FALL ON UNCANISTERED FUEL WASTE PACKAGE DESIGNS (SCPB: N/A)
The objective of this analysis is to explore the Uncanistered Fuel (UCF) Tube Design waste package (WP) resistance to rock falls. This analysis will also be used to determine the size of rock that can strike the WP without causing failure in the containment barriers from a height based on the starter tunnel dimensions. The purpose of this analysis is to document the models and methods used in the calculations. digital.library.unt.edu/ark:/67531/metadc792228/
Energy R and D in Japan
In 1997, the public and private sectors in Japan invested $90.3 billion in R and D. Japan is the second largest supporter of R and D after the United States. A very large percentage (79.4%) of all R and D in Japan is supported by the private sector. The prolonged economic recession that has plagued the Japanese economy for most of the 1990s has significantly reduced the scale of the Japanese R and D effort compared to what it would have been had the economy been more robust. The Japanese government has recently attempted to bring the economy out of this recession through the use of economic stimulus packages. These stimulus packages have contained significant new funding for R and D, although it is apparent that much of the funding is going to R and D programs and R and D construction projects with very near tern payoff and not to the support of longer term R and D. In 1998, the Japanese government devoted 13.7% of all public R and D funds to the support of energy R and D. The priority accorded to energy R and D in Japan is significantly higher than in any other industrialized nation. The Japanese energy R and D program, which was funded at $2.5 billion in 1997, is overwhelmingly focused on nuclear energy R and D. Nuclear energy R and D (fission and fusion) accounts for 75% of the total national energy R and D budget. The fission energy R and D effort has decreased nearly 24% since 1996 as the government attempts to refocus this program in the face of growing public opposition to the Japanese government's efforts to expand the nuclear power program. Energy efficiency R and D (8% of the total national energy R and D budget) and renewable energy R and D receive relatively modest support from the Japanese government. digital.library.unt.edu/ark:/67531/metadc792291/
Radioactive materials released from nuclear power plants. Volume 13, Annual report 1992
Releases of radioactive materials in airborne and liquid effluents from commercial light water reactors during 1992 have been compiled and reported. The summary data for the years 1973 through 1991 are included for comparison. Data on solid waste shipments as well as selected operating information have been included. This report supplements earlier annual reports issued by the former Atomic Energy Commission and the Nuclear Regulatory Commission. The 1992 release data are summarized in tabular form. Data covering specific radionuclides are summarized. digital.library.unt.edu/ark:/67531/metadc792252/
Federal facilities compliance act waste management
Site Treatment Plans (STPs) developed through the Federal Facilities Compliance Act pose many technical and administrative challenges. Legacy wastes managed under these plans require Land Disposal Restriction (LDR) compliance through treatment and ultimate disposal. Although capacity has been defined for most of the Department of Energy wastes, many waste streams require further characterization and many need additional treatment and handling beyond LDR criteria to be able to dispose of the waste. At Lawrence Livermore National Laboratory (LLNL), the Hazardous Waste Management Division has developed a comprehensive Legacy Waste Program. The program directs work to manage low level and mixed wastes to ensure compliance with nuclear facility rules and its STP. This paper provides a survey of work conducted on these wastes at LLNL. They include commercial waste treatment and disposal, diverse forms of characterization, inventory maintenance and reporting, on-site treatment, and treatability studies. These activities are conducted in an integrated fashion to meet schedules defined in the STP. The processes managing wastes are dynamic due to required integration of administrative, regulatory, and technical concerns spanning the gamut to insure safe proper disposal. digital.library.unt.edu/ark:/67531/metadc792241/
Measurement of inclusive triple differential dijet cross section, d{sup 3}{sigma}/dE{sub T}d{eta}{sub 1}d{eta}{sub 2} in p{bar p} collisions at {radical}s = 1.8 TeV
Measurement of the inclusive triple differential dijet cross section, d{sup 3}{sigma}/dE{sub T}d{sub {eta}1}d{sub {eta}2}, at a center of mass energy {radical}s = 1.8 TeV with the D0 detector during the 1992--1993 run. The sensitivity of this measurement to different parton distribution functions is explored. A comparison of the data to NLO theory using different parton distributions functions indicates the need for a smaller gluon content in the x range accessible at the Tevatron than is predicted by current parton distribution sets. digital.library.unt.edu/ark:/67531/metadc792069/
Oxidation Reactions of Ethane over Ba-Ce-O Based Perovskites
Ethane oxidation reactions were studied over pure and Ca-, Mg-, Sr-, La-, Nd-, and Y-substituted BaCeO{sub 3} perovskites under oxygen limited conditions. Several of the materials, notably the Ca- and Y-substituted materials, show activity for complete oxidation of the hydrocarbon to CO{sub 2} at temperatures below 650 C. At higher temperatures, the oxidative dehydrogenation (ODH) to ethylene becomes significant. Conversions and ethylene yields are enhanced by the perovskites above the thermal reaction in our system in some cases. The perovskite structure is not retained in the high temperature reaction environment. Rather, a mixture of carbonates and oxides is formed. Loss of the perovskite structure correlates with a loss of activity and selectivity to ethylene. digital.library.unt.edu/ark:/67531/metadc792073/
Polarization sensitive optical coherence tomography detection method
This study demonstrates the potential of polarization sensitive optical coherence tomography (PS-OCT) for non-invasive in vivo detection and characterization of early, incipient caries lesions. PS-OCT generates cross-sectional images of biological tissue while measuring the effect of the tissue on the polarization state of incident light. Clear discrimination between regions of normal and demineralized enamel is first shown in PS-OCT images of bovine enamel blocks containing well-characterized artificial lesions. High-resolution, cross-sectional images of extracted human teeth are then generated that clearly discriminate between the normal and carious regions on both the smooth and occlusal surfaces. Regions of the teeth that appeared to be demineralized in the PS-OCT images were verified using histological thin sections examined under polarized light microscopy. The PS-OCT system discriminates between normal and carious regions by measuring the polarization state of the back-scattered 1310 nm light, which is affected by the state of demineralization of the enamel. Demineralization of enamel increases the scattereing coefficient, thus depolarizing the incident light. This study shows that PS-OCT has great potential for the detection, characterization, and monitoring of incipient caries lesions. digital.library.unt.edu/ark:/67531/metadc792088/
Recycling and Energy Recovery Pilot Project: Project Report and Future Efforts
A novel bioprocessing technology was developed that efficiently converts negative-value organic waste, including domestic refuse, animal manures, industrial wastes, food processing wastes, and municipal sewage sludge into saleable products, including fuel gas and compost. This technology is known as high solids anaerobic digestion and was developed at NREL from fundamental research to laboratory- and intermediate-scale system evaluations. digital.library.unt.edu/ark:/67531/metadc792000/
Large-eddy simulation of the Rayleigh-Taylor instability on a massively parallel computer
A computational model for the solution of the three-dimensional Navier-Stokes equations is developed. This model includes a turbulence model: a modified Smagorinsky eddy-viscosity with a stochastic backscatter extension. The resultant equations are solved using finite difference techniques: the second-order explicit Lax-Wendroff schemes. This computational model is implemented on a massively parallel computer. Programming models on massively parallel computers are next studied. It is desired to determine the best programming model for the developed computational model. To this end, three different codes are tested on a current massively parallel computer: the CM-5 at Los Alamos. Each code uses a different programming model: one is a data parallel code; the other two are message passing codes. Timing studies are done to determine which method is the fastest. The data parallel approach turns out to be the fastest method on the CM-5 by at least an order of magnitude. The resultant code is then used to study a current problem of interest to the computational fluid dynamics community. This is the Rayleigh-Taylor instability. The Lax-Wendroff methods handle shocks and sharp interfaces poorly. To this end, the Rayleigh-Taylor linear analysis is modified to include a smoothed interface. The linear growth rate problem is then investigated. Finally, the problem of the randomly perturbed interface is examined. Stochastic backscatter breaks the symmetry of the stationary unstable interface and generates a mixing layer growing at the experimentally observed rate. 115 refs., 51 figs., 19 tabs. digital.library.unt.edu/ark:/67531/metadc792281/
The level 1 central tracking trigger for the D-Zero upgrade
The D0 level 1 tracking trigger uses data from the scintillating fiber tracker, the central and forward preshower detectors, the muon system and the calorimeter. Tracks are found in the scintillating fiber tracker with transverse momentum greater than 1.5 GeV/c. The tracks are then sent to the central preshower detector for electron tagging and to the muon system for muon tagging. Preshower clusters are also used for identifying photon candidates. These multi detector triggers are then sent to the level 1 Trigger Framework where they are further combined with the calorimeter to create the final level 1 trigger. This paper presents an overview of the level 1 trigger system with emphasis on the use of large programmable logic devices (PLD�s) in an extensible system architecture that allows complex, multi detector triggers. digital.library.unt.edu/ark:/67531/metadc792219/
Fabrication of High Performance Microlenses for an Integrated Capillary Channel Electrochromatograph with Fluorescence Detection
We describe the microfabrication of an extremely compact optical system as a key element in an integrated capillary channel electrochromatograph with fluorescence detection. The optical system consists of a vertical cavity surface-emitting laser (VCSEL), two high performance microlenses and a commercial photodetector. The microlenses are multilevel diffractive optics patterned by electron beam lithography and etched by reactive ion etching in fused silica. The design uses substrate-mode propagation within the fused silica substrate. Two generations of optical subsystems are described. The first generation design has a 6 mm optical length and is integrated directly onto the capillary channel-containing substrate. The second generation design separates the optical system onto its own substrate module and the optical path length is further compressed to 3.5 mm. The first generation design has been tested using direct fluorescence detection with a 750 nm VCSEL pumping a 10{sup {minus}4}M solution of CY-7 dye. The observed signal-to-noise ratio of better than 100:1 demonstrates that the background signal from scattered pump light is low despite the compact size of the optical system and is adequate for system sensitivity requirements. digital.library.unt.edu/ark:/67531/metadc792227/
Mobile Surveillance and Monitoring Robots
Long-term nuclear material storage will require in-vault data verification, sensor testing, error and alarm response, inventory, and maintenance operations. System concept development efforts for a comprehensive nuclear material management system have identified the use of a small flexible mobile automation platform to perform these surveillance and maintenance operations. In order to have near-term wide-range application in the Complex, a mobile surveillance system must be small, flexible, and adaptable enough to allow retrofit into existing special nuclear material facilities. The objective of the Mobile Surveillance and Monitoring Robot project is to satisfy these needs by development of a human scale mobile robot to monitor the state of health, physical security and safety of items in storage and process; recognize and respond to alarms, threats, and off-normal operating conditions; and perform material handling and maintenance operations. The system will integrate a tool kit of onboard sensors and monitors, maintenance equipment and capability, and SNL developed non-lethal threat response technology with the intelligence to identify threats and develop and implement first response strategies for abnormal signals and alarm conditions. System versatility will be enhanced by incorporating a robot arm, vision and force sensing, robust obstacle avoidance, and appropriate monitoring and sensing equipment. digital.library.unt.edu/ark:/67531/metadc792257/
Probabilistic Accident Consequence Uncertainty - A Joint CEC/USNRC Study
The joint USNRC/CEC consequence uncertainty study was chartered after the development of two new probabilistic accident consequence codes, MACCS in the U.S. and COSYMA in Europe. Both the USNRC and CEC had a vested interest in expanding the knowledge base of the uncertainty associated with consequence modeling, and teamed up to co-sponsor a consequence uncertainty study. The information acquired from the study was expected to provide understanding of the strengths and weaknesses of current models as well as a basis for direction of future research. This paper looks at the elicitation process implemented in the joint study and discusses some of the uncertainty distributions provided by eight panels of experts from the U.S. and Europe that were convened to provide responses to the elicitation. The phenomenological areas addressed by the expert panels include atmospheric dispersion and deposition, deposited material and external doses, food chain, early health effects, late health effects and internal dosimetry. digital.library.unt.edu/ark:/67531/metadc792020/
Improving the diversity of manufacturing electroluminescent flat panel displays
Crystalline calcium thiogallate with a cerium dopant has been deposited by metal-organic chemical vapor deposition (MOCVD) at temperatures below 600{degrees}C on a low cost glass substrate. An EL luminance of 1.05 fL was observed 40 volts above threshold at 60 Hz. This is more than an order of magnitude improvement over earlier crystalline-as-deposited thiogallate materials. These results pave the way for the use of MOCVD as a potential method for processing full color thin-film electroluminescent (TFEL) flat panel displays. The formation of the CaGa{sub 2}S{sub 4}:Ce phosphor requires precise control over a number of deposition parameters including flow rates, substrate temperature, and reactor pressure. The influence of these parameters will be discussed in terms of structure, uniformity, and TFEL device performance. digital.library.unt.edu/ark:/67531/metadc792266/
Fluorescent Optical Liquid-Level Sensor
An optical method of detecting liquid level is presented that uses fluorescence radiation generated in an impurity-doped glass or plastic slab. In operation, the slab is inserted into the liquid and pump light is coupled into it so that the light is guided by the slab-air interface above the liquid and escapes into the liquid just below its surface. Since the fluorescence is generated only in that section of the slab above the liquid, the fluorescence power will monotonically decrease with increasing liquid level. Thus, a relationship can be established between any signal proportional to it and the liquid level. Because optical fibers link the pump source and the detector of fluorescence radiation to the sensor, no electrical connections are needed in or near the liquid. Their absence vastly decreases the hazard associated with placing a liquid-level sensor in a potentially explosive environment. A laboratory prototype, consisting of a methyl styrene slab doped with an organic dye, has been built and successfully tested in water. Its response to liquid level when pumped by a tunable argon-ion laser at 476, 488, and 496 nm, and by a blue LED, is presented and shown to be consistent with theory. The fluorescence spectra are also presented and discussed. digital.library.unt.edu/ark:/67531/metadc792243/
Radiation-turbulence interactions in pulverized-coal flames. Technical report for quarter VI, December 15, 1994--March 30, 1995
The purpose of this paper is to discuss the nature of the unsteady interactions between buoyant turbulence and radiation feedback to the center of flames. An unfiltered additive turbulent decomposition (ATD) is carried out in a manner similar to that originally developed by McDonough and co-workers for studying Burgers` equation. The new approach is philosophically similar to LES; namely, treat the large and small scales separately. However, the technique requires no formal filtering or averaging for the large-scale equations. and the corresponding subgrid-scale models are obtained as local spectral approximations of the original governing equations. In the present work, only the small-scale part of the governing equations has been solved, and the large-scale parameters are to be obtained directly from either a global computer program or from corresponding experimental results. Preliminarily calculated results show that the radiation in the flame markedly influences the flow in the center of flame, and even periodic radiation fluctuations can lead to chaotic behavior of the flow. The extent to which the flow fluctuates not only depends on fluctuation of radiative properties, but also on the profile of the mean absorption coefficient. digital.library.unt.edu/ark:/67531/metadc792282/
Use grading of classified slugs
This memorandum discusses an agreement reached by members of the Technical Division, Operating Department, and Technical Department as to groups of slug classifications to be assigned to regions of varying degrees of severity of exposure in the pile. Estimates of the slugs to be available in the groups established are included herein, together with a plan for allocation to the pile. digital.library.unt.edu/ark:/67531/metadc792268/
Cross-Industry Performance Modeling: Toward Cooperative Analysis
One of the current unsolved problems in human factors is the difficulty in acquiring information from lessons learned and data collected among human performance analysts in different domains. There are several common concerns and generally accepted issues of importance for human factors, psychology and industry analysts of performance and safety. Among these are the need to incorporate lessons learned in design, to carefully consider implementation of new designs and automation, and the need to reduce human performance-based contributions to risk. In spite of shared concerns, there are several road blocks to widespread sharing of data and lessons learned from operating experience and simulation, including the fact that very few publicly accessible data bases exist(Gertman & Blackman, 1994, and Kirwan, 1997). There is a need to draw together analysts and analytic methodologies to comprise a centralized source of data with sufficient detail to be meaningful while ensuring source anonymity. We propose that a generic source of performance data and a multi-domain data store may provide the first steps toward cooperative performance modeling and analysis across industries. digital.library.unt.edu/ark:/67531/metadc792240/
Carboxylic Acid Modified [Ti({mu}-ONep)(Onep){sub 3}]{sub 2} Compounds. Syntheses, Characterizations, X-Ray Structures, and Implications for the Thin Film Densification of TiO{sub 2} from Ti{sub 3}({mu}{sub 3}-O)(O{sub 2}CH){sub 2}(ONep){sub 8}, etc.
No abstract prepared. digital.library.unt.edu/ark:/67531/metadc792248/
Cooperative Monitoring Center Occasional Paper/11: Cooperative Environmental Monitoring in the Coastal Regions of India and Pakistan
The cessation of hostilities between India and Pakistan is an immediate need and of global concern, as these countries have tested nuclear devices, and have the capability to deploy nuclear weapons and long-range ballistic missiles. Cooperative monitoring projects among neighboring countries in South Asia could build regional confidence, and, through gradual improvements in relations, reduce the threat of war and the proliferation of weapons of mass destruction. This paper discusses monitoring the trans-border movement of flow and sediment in the Indian and Pakistani coastal areas. Through such a project, India and Pakistan could initiate greater cooperation, and engender movement towards the resolution of the Sir Creek territorial dispute in their coastal region. The Joint Working Groups dialogue being conducted by India and Pakistan provides a mechanism for promoting such a project. The proposed project also falls within a regional framework of cooperation agreed to by several South Asian countries. This framework has been codified in the South Asian Seas Action Plan, developed by Bangladesh, India, Maldives, Pakistan and Sri Lanka. This framework provides a useful starting point for Indian and Pakistani cooperative monitoring in their trans-border coastal area. The project discussed in this paper involves computer modeling, the placement of in situ sensors for remote data acquisition, and the development of joint reports. Preliminary computer modeling studies are presented in the paper. These results illustrate the cross-flow connections between Indian and Pakistani coastal regions and strengthen the argument for cooperation. Technologies and actions similar to those suggested for the coastal project are likely to be applied in future arms control and treaty verification agreements. The project, therefore, serves as a demonstration of cooperative monitoring technologies. The project will also increase people-to-people contacts among Indian and Pakistani policy makers and scientists. In the perceptions of the general public, the project will crystallize the idea that the two countries share ecosystems and natural resources, and have a vested interest in increased collaboration. digital.library.unt.edu/ark:/67531/metadc792208/
Integration of Environmental Restoration and Decontamination and Dismantlement Requirements at the INEEL
In 1997, the Environmental Restoration Program at the Idaho National Engineering and Environmental Laboratory (INEEL) determined that it was necessary to remediate a Comprehensive Environmental Response and Liability Act (CERCLA) site to address the risk of subsurface petroleum contamination to human health and the environment. This cleanup project was conducted utilizing the Non-time Critical Removal Action process. Due to the close proximity (above the contaminated soil) of a number of above ground storage tanks and a building, the CERCLA project team worked closely with the D&D group to ensure all requirements for each program were met. Lessons learned and regulatory requirements are discussed in the paper, including the factors unknown to many ER personnel regarding the steps required to be completed prior to the dismantlement of structures. The paper summarizes the background associated with the site, why the removal action was conducted, the scope of the removal action, and the results. The emphasis of the paper is to discuss the integration between ER and D&D requirements and processes. In the current environment where ER and D&D activities are commingled, it is imperative that ER and D&D personnel are aware of the requirements imposed upon each program. By working together and building upon the strengths of each program, the INEEL�s 1997 removal action was a tremendous success. digital.library.unt.edu/ark:/67531/metadc792283/
US/Russian Laboratory-to-Laboratory MPC&A at the RRC Kurchatov Institute
Formal interactions with Kurchatov Institute (KI) began summer 1994 on material protection, control and accountability (MPC&A). Contracts were placed by LANL and Sandia with KI to implement a nuclear material accounting system and a physical security system at a KI demonstration facility which contain two critical assemblies with special nuclear material. LLNL implemented May 1995 a task to measure by gamma-ray spectroscopy the uranium enrichment of fuel in the facility. This laboratory-to-laboratory effort is part of the cooperative program between US and Russian institutes in nuclear material nonproliferation. In 1994-5, KI personnel demonstrated the physical security system. The next facility for work in MPC&A at KI is the Central Storage Facility, which is important for the computerized material accounting system for KI. digital.library.unt.edu/ark:/67531/metadc792278/
Pressure vessels and piping systems: general requirements and documentation for testing
Pressure vessel and piping systems are widely used throughout industry and research laboratories and contain a very large concentration of energy, and yet, despite the fact that their design and installation comply with federal, state and local regulations and recognized industrial standards, there continue to be serious pressure equipment failures. There are many reasons for pressure equipment failure: degradation and thinning of materials with usage, aging, hidden flaws during fabrication, etc. Fortunately, periodic testing and internal and external inspections significantly improve the safety of a pressure vessel or facility. A good testing and inspection program is based on development of procedures for specific industries or types of vessels. This paper describes the elements that should be a part of a pressure testing safety program and the requirements that it should address. The program should comply with pressure safety standards and include the requirements for inspecting pressure vessels, establishing and implementing a written pressure system test work permit, maintaining safety in the testing area, developing in-place pressure testing procedures, keeping records for pressure test calculations and results, and evaluating the system's internal and external integrity. digital.library.unt.edu/ark:/67531/metadc792262/
Cooperative Efforts Raise Building Energy Codes and Appliance Standards
An overview of the U.S. Department of Energy Office of Codes and Standards programs to establish minimum efficiency codes, standards, and guidelines for reduced energy use and lower operating costs in U.S. building components. digital.library.unt.edu/ark:/67531/metadc792067/
Analysis of Subsidence Data for the Big Hill Site, Texas
The elevation change data measured at the Big Hill SPR site over the last 10 years has been studied and a model utilized to project elevation changes into the future. The subsidence rate at Big Hill is low in comparison with other Strategic Petroleum Reserve sites and has decreased with time due to the maintenance of higher operating pressures and the normal decrease in creep closure rate of caverns with time. However, the subsidence at the site is projected to continue. A model was developed to project subsidence values 20 years into the future; no subsidence related issues are apparent from these projections. digital.library.unt.edu/ark:/67531/metadc792046/
Large persistent photochromic effect due to DX centers in AlSb doped with selenium
A large photochromic effect has been observed in bulk AlSb crystals doped with Se. Illumination with light of energy higher than 1 eV leads to an increase of the absorption coefficient in the spectral range 0.1 to 1.6 eV. The enhanced absorption is persistent at temperatures below about K. The effect is a manifestation of a DX-like bistability of Se donors. The illumination transfers the from the DX center to a metastable hydrogenic level. The increased absorption with peaks around 0.2 eV and 0.5 is due to photoionization from the donor level to X{sub l} and X{sub 3} minima of the conduction band. digital.library.unt.edu/ark:/67531/metadc792025/
Wellhead protection area delineation under uncertainty
A program to protect groundwater resources used for water supply from all potential threats due to contamination was established in the Amendments to the Safe Drinking Water Act (SDWA). Goal of the State Wellhead Protection (WHP) Program is to ``protect wellhead areas within their jurisdiction from contaminants which may have any adverse effect on the health of persons.`` A major component of WHP is the determination of zones around water-supply wells called Wellhead Protection Areas (WHPAs) within which contaminant source assessment and management should be addressed. WHPAs are defined in the SDWA as ``the surface and subsurface area surrounding a water well or wellfield, supplying a public water system, through which contaminants are reasonably likely to move toward and reach such water well or wellfield.`` A total of 14 water-supply wells are currently being used at the Nevada Test Site (NTS). Eleven of the wells are used for potable water supplies and the remaining three wells are used for construction purposes only. Purpose of this study is to estimate WHPAs for each water-supply well at the NTS. Due to the limited information about the hydraulic properties needed for estimating the WHPAS, an approach that considered the uncertainty in the estimates of the hydraulic properties was developed and implemented. digital.library.unt.edu/ark:/67531/metadc792099/
Application of Systems Engineering to U.S. Department of Energy Privatization Project Selection at the Hanford Nuclear Reservation
The privatization efforts at the U.S. Department of Energy's Hanford Nuclear Reservation have been very successful primarily due to a disciplined process for project selection and execution. Early in the development of Privatization at Hanford, the Department of Energy determined that a disciplined alternatives generation and analysis (AGA) process would furnish the candidate projects with the best probability for success. Many factors had to be considered in the selection of projects. Westinghouse Hanford Company was assigned to develop this process and facilitate the selection of the first round of candidate privatization projects. Team members for the AGA process were assembled from all concerned organizations and skill groups. Among the selection criteria were legal, financial and technical considerations which had to be weighed. digital.library.unt.edu/ark:/67531/metadc792085/
The effect of uncertainties in nuclear reactor plant-specific failure data on core damage frequency
It is sometimes the case in PRA applications that reported plant-specific failure data are, in fact, only estimates which are uncertain. Even for detailed plant-specific data, the reported exposure time or number of demands is often only an estimate of the actual exposure time or number of demands. Likewise the reported number of failure events or incidents is sometimes also uncertain because incident or malfunction reports may be ambiguous. In this report we determine the corresponding uncertainty in core damage frequency which can b attributed to such uncertainties in plant-specific data using a simple but typical nuclear power reactor example. digital.library.unt.edu/ark:/67531/metadc792263/
Use of the Known-M Method for NDA of Plutonium Scrap
'Plutonium scrap from another Department of Energy site is to be converted at Savannah River Site (SRS) to a form for permanent storage. For accountability and criticality safety, the material must be measured at SRS, and handling restrictions require assay in 9975 shipping drums. A Multiplicity Neutron Counter is available to perform the measurements, but requires about 12 hours per assay, too long to support the measurement schedule. The assay time has been reduced to 2 hours by use of the Known-M method, the first known routine application of Known-M. The approach involves expression of the multiplication in terms of the effective <sup>239</sup>Pu mass and a quadratic polynomial. Because only a few measured values of multiplication were available, values from Monte Carlo neutron transport calculations (using code MCNP) were used. Because the scrap cans have variable fill heights and fill height affects multiplication, an algorithm to correct the effective <sup>239</sup>Pu mass values for that effect was developed. Testing of the Known-M calibration with limited data suggests a 2-sigma uncertainty of about 5 percent. Drums can contain one or two individual scrap cans, and an algorithm for measuring the combined plutonium content in two cans was developed. The Known-M assay calculations will be performed off line using a spreadsheet.' digital.library.unt.edu/ark:/67531/metadc793604/
Report on Biomass Drying Technology
Using dry fuel provides significant benefits to combustion boilers, mainly increased boiler efficiency, lower air emissions, and improved boiler operation. The three main choices for drying biomass are rotary dryers, flash dryers, and superheated steam dryers. Which dryer is chosen for a particular application depends very much on the material characteristics of the biomass, the opportunities for integrating the process and dryer, and the environmental controls needed or already available. digital.library.unt.edu/ark:/67531/metadc793623/
DEFORMATION MONITORING ANALYSIS
No Description digital.library.unt.edu/ark:/67531/metadc792030/
Analysis of F-Canyon Effluents During the Dissolution Cycle with a Fourier Transform Infrared Spectrometer/Multipath Cell
Air samples from F-Canyon effluents were collected at the F-Canyon stack and transported to a laboratory at the Savannah River Technology Center (SRTC) for analysis using a Fourier transform infrared spectrometer in conjunction with a multipath cell. Air samples were collected during the decladding and acid cuts of the dissolution of the irradiated aluminum-cladded slugs. The FTIR analyses of the air samples show the presence of NO2, NO, HNO2, N2O, SF6, and 85Kr during the dissolution cycle. The concentration time profiles of these effluents corresponded with expected release rates from the F-Canyon operations. digital.library.unt.edu/ark:/67531/metadc792014/
EDI as a Treatment Module in Recycling Spent Rinse Waters
Recycling of the spent rinse water discharged from the wet benches commonly used in semiconductor processing is one tactic for responding to the targets for water usage published in the 1997 National Technology Roadmap for Semiconductors (NTRS). Not only does the NTRS list a target that dramatically reduces total water usage/unit area of silicon manufactured by the industry in the future but for the years 2003 and beyond, the NTRS actually touts goals which would have semiconductor manufacturers drawing less water from a regional water supply per unit area of silicon manufactured than the quantity of ultrapure water (UPW) used in the production of that same silicon. Achieving this latter NTRS target strongly implies more widespread recycling of spent rinse waters at semiconductor manufacturing sites. In spite of the fact that, by most metrics, spent rinse waters are of much higher purity than incoming municipal waters, recycling of these spent rinse waters back into the UPW production plant is not a simple, straightforward task. The rub is that certain of the chemicals used in semiconductor manufacturing, and thus potentially present in trace concentrations (or more) in spent rinse waters, are not found in municipal water supplies and are not necessarily removed by the conventional UPW production sequence used by semiconductor manufacturers. Some of these contaminants, unique to spent rinse waters, may actually foul the resins and membranes of the UPW system, posing a threat to UPW production and potentially even causing a shutdown. digital.library.unt.edu/ark:/67531/metadc792057/
Clean Cities Award Winning Coalition: Chicago
The Chicago area coalition marks its five-year anniversary in 1999 as a member of the Clean Cities Program. Their progress in the last five years has been remarkable as they advance the alternative fuel and vehicle markets, increase coalition membership, help support new alternative fuel vehicle (AFV) legislation, and educate fleet managers. The coalition boasts more than 90 stakeholders, including industry, government, environmental and academic organizations, and membership continues to grow. Thanks to dedicated coalition members' efforts, a variety of AFVs can be seen on Chicago's streets, including transit and school buses, taxicabs, sedans, vans, and trucks. digital.library.unt.edu/ark:/67531/metadc792322/
Uncertainty Analysis of Nondestructive Assay Measurements of Nuclear Waste
Regulatory agencies governing the disposal of nuclear waste require that the waste be appropriately characterized prior to disposition. The most important aspect of the characterization process, establishing radionuclide content, is often achieved by nondestructive assay (NDA). For NDA systems to be approved for use in these applications, measurement uncertainty must be established. Standard �propagation of errors� methods provide a good starting point for considering the uncertainty analysis of NDA systems for nuclear waste. However, as compared with other applications (e.g., nuclear material accountability), using NDA systems for nuclear waste measurements presents some unique challenges. These challenges, stemming primarily from the diverse nature of the waste materials encountered, carry over into the uncertainty analysis as well. This paper reviews performance measures appropriate for the assessment of NDA uncertainty, describes characteristics of nuclear waste measurements that contribute to difficulties in assessing uncertainty, and outlines some statistics based methods for incorporating variability in waste characteristics in an uncertainty analysis. digital.library.unt.edu/ark:/67531/metadc792082/
Energy R&amp;D in the United States
In 1997, the US public and private sectors invested $205.7 billion in R&amp;D. Private sector investments in R&amp;D increased 34% between 1990 and 1997; over the same period the federal government decreased its expenditures by 15% in real terms. Projections of outyear federal budgets indicate the federal government will continue to reduce its investments in R&amp;D for the foreseeable future. Defense R&amp;D continues to be the largest area of concentration for federal government's R&amp;D investments, with defense R&amp;D accounting for 54% of all federal R&amp;D outlays in 1998. Defense R&amp;D is funded at a level which is there times higher than health R&amp;D. Health R&amp;D has experienced the largest inflation-adjusted increases of any federal R&amp;D program, up 21% in real terms since 1990. US national (i.e., public and private) investments in energy R&amp;D currently stand at a 23-year low of $4.4 billion in 1996. Federal support for energy R&amp;D has declined 22% in real terms between 1990 and 1996. Federal energy R&amp;D investments are also undergoing changes in priority. Fossil energy R&amp;D programs are at the beginning of a potentially significant change away from ''clean coal'' technology development programs and towards more fundamental research on ways to decarbonize fossil fuels and sequester carbon dioxide. The federal nuclear energy R&amp;D program has restarted (at a modest level) research to develop new reactor concepts after many years of no federal research in this area. The United States has withdrawn from the ITER project, calling into question the viability of this international fusion energy program. Renewable energy and energy efficiency R&amp;D programs continue to be the only consistent areas of growth in the federal energy R&amp;D budget. digital.library.unt.edu/ark:/67531/metadc792068/
Accelerated Aging of Polymer Composite Bridge Materials
Accelerated aging research on samples of composite material and candidate ultraviolet (UV) protective coatings is determining the effects of six environmental factors on material durability. Candidate fastener materials are being evaluated to determine corrosion rates and crevice corrosion effects at load-bearing joints. This work supports field testing of a 30-ft long, 18-ft wide polymer matrix composite (PMC) bridge at the Idaho National Engineering and Environmental Laboratory (INEEL). Durability results and sensor data from tests with live loads provide information required for determining the cost/benefit measures to use in life-cycle planning, determining a maintenance strategy, establishing applicable inspection techniques, and establishing guidelines, standards, and acceptance criteria for PMC bridges for use in the transportation infrastructure. digital.library.unt.edu/ark:/67531/metadc792040/
Ratepayer-funded energy-efficiency programs in a restructuredelectri city industry: Issues and options for regulators andlegislators
Electric industry restructuring requires state regulators and legislators to re-examine the purposes served by and the continuing need for ratepayer-funded energy-efficiency programs, as well as the mechanisms to collect funds for these programs and the institutions appropriate to administer them. This paper offers background to these issues and a series of recommendations based on analysis of recent state experiences. Our recommendations are summarized. digital.library.unt.edu/ark:/67531/metadc792070/
Sorption Energy Maps of Clay Mineral Surfaces
A molecular-level understanding of mineral-water interactions is critical for the evaluation and prediction of the sorption properties of clay minerals that may be used in various chemical and radioactive waste disposal methods. Molecular models of metal sorption incorporate empirical energy force fields, based on molecular orbital calculations and spectroscopic data, that account for Coulombic, van der Waals attractive, and short-range repulsive energies. The summation of the non-bonded energy terms at equally-spaced grid points surrounding a mineral substrate provides a three dimensional potential energy grid. The energy map can be used to determine the optimal sorption sites of metal ions on the exposed surfaces of the mineral. By using this approach, we have evaluated the crystallographic and compositional control of metal sorption on the surfaces of kaolinite and illite. Estimates of the relative sorption energy and most stable sorption sites are derived based on a rigid ion approximation. digital.library.unt.edu/ark:/67531/metadc792015/
The Role of Electron Transport and Trapping in MOS Total-Dose Modeling
Radiation-induced hole and electron transport and trapping are fundamental to MOS total-dose models. Here we separate the effects of electron-hole annihilation and electron trapping on the neutralization of radiation-induced charge during switched-bias irradiation for hard and soft oxides, via combined thermally stimulated current (TSC) and capacitance-voltage measurements. We also show that present total-dose models cannot account for the thermal stability of deeply trapped electrons near the Si/SiO{sub 2} interface, or the inability of electrons in deep or shallow traps to contribute to TSC at positive bias following (1) room-temperature, (2) high-temperature, or (3) switched-bias irradiation. These results require revisions of modeling parameters and boundary conditions for hole and electron transport in SiO{sub 2}. The nature of deep and shallow electron traps in the near-interfacial SiO{sub 2} is discussed. digital.library.unt.edu/ark:/67531/metadc792021/
Coupled Resonator Vertical Cavity Laser Diodes
For many applications, the device performance of edge emitting semiconductor lasers can be significantly improved through the use of multiple section devices. For example, cleaved coupled cavity (C3) lasers have been shown to provide single mode operation, wavelength tuning, high speed switching, as well as the generation of short pulses via mode-locking and Q-switching [1]. Using composite resonators within a vertical cavity laser opens up new possibilities due to the unique ability to tailor the coupling between the monolithic cavities, incorporate passive or active resonators which are spectrally degenerate or detuned, and to fabricate these devices in 2-dimensional arrays. Composite resonator vertical cavity lasers (CRVCL) have been examined using optical pumping and electrical injection [2-5]. We report on CRVCL diodes and show that efficient modulation of the laser emission can be achieved by either forward or reverse biasing the passive cavity within a CRVCL. digital.library.unt.edu/ark:/67531/metadc792060/
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