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  Partner: UNT Libraries Government Documents Department
 Decade: 1990-1999
Advances in the determination of quark masses
Significant progress has been made in the determination of the light quark masses, using both lattice QCD and sum rule methods, in the last year. The authors discuss the different methods and review the status of current results. Finally, they review the calculation of bottom and charm masses. digital.library.unt.edu/ark:/67531/metadc702585/
Advances in the development of FTIR continuous emission monitor for incinerators
The integrated, transportable FTIR-CEM was successfully tested from September 13 to 21, 1994, at the K-25 TSCA incinerator, in Oak Ridge, Tennessee. the field test followed the requirements of a procedure, which was submitted to the EPA for approval. The test results met all the requirement listed in the proposed procedure. Extensive spiking tests were conducted during the field test. The FTIR-CEM quantitatively detected all spiked analytes measured the stack emission variation during the ignition period of the incinerator. For the stack samples obtained under normal incineration conditions, no target analytes were detected at concentrations above the instrument detection limits, except for methane, which was occasionally detected at 4-5 ppM. Future work will involve making the master control software more robust to use, improving the accuracy of the analytical methods, and testing system effectiveness for various emission sources. A commercial version of the system is currently being developed. digital.library.unt.edu/ark:/67531/metadc793433/
Advances in the operation of the DIII-D neutral beam computer systems
The DIII-D neutral beam system routinely provides up to 20 MW of deuterium neutral beam heating in support of experiments on the DIII-D tokamak, and is a critical part of the DIII-D physics experimental program. The four computer systems previously used to control neutral beam operation and data acquisition were designed and implemented in the late 1970`s and used on DIII and DIII-D from 1981--1996. By comparison to modern standards, they had become expensive to maintain, slow and cumbersome, making it difficult to implement improvements. Most critical of all, they were not networked computers. During the 1997 experimental campaign, these systems were replaced with new Unix compliant hardware and, for the most part, commercially available software. This paper describes operational experience with the new neutral beam computer systems, and new advances made possible by using features not previously available. These include retention and access to historical data, an asynchronously fired ``rules`` base, and a relatively straightforward programming interface. Methods and principles for extending the availability of data beyond the scope of the operator consoles will be discussed. digital.library.unt.edu/ark:/67531/metadc697220/
Advances in the reduction and compensation of film stress in high-reflectance multilayer coatings for extreme ultraviolet lithography applications
Due to the stringent surface figure requirements for the multilayer-coated optics in an extreme ultraviolet (EUV) projection lithography system, it is desirable to minimize deformation due to the multilayer film stress. However, the stress must be reduced or compensated without reducing EUV reflectivity, since the reflectivity has a strong impact on the throughput of a EUV lithography tool. In this work we identify and evaluate several leading techniques for stress reduction and compensation as applied to Mo/Si and Mo/Be multilayer films. The measured film stress for Mo/Si films with EUV reflectances near 67.4% at 13.4 nm is approximately - 420 MPa (compressive), while it is approximately +330 MPa (tensile) for Mo/Be films with EUV reflectances near 69.4% at 11.4 nm. Varying the Mo-to-Si ratio can be used to reduce the stress to near zero levels, but at a large loss in EUV reflectance (> 20%). The technique of varying the base pressure (impurity level) yielded a 10% decrease in stress with a 2% decrease in reflectance for our multilayers. Post-deposition annealing was performed and it was observed that while the cost in reflectance is relatively high (3.5%) to bring the stress to near zero levels (i.e., reduce by 1 00%), the stress can be reduced by 75% with only a 1.3% drop in reflectivity at annealing temperatures near 200{degrees}C. A study of annealing during Mo/Si deposition was also performed; however, no practical advantage was observed by heating during deposition. A new non-thermal (athermal) buffer-layer technique was developed to compensate for the effects of stress. Using this technique with amorphous silicon and Mo/Be buffer-layers it was possible to obtain Mo/Be and Mo/Si multilayer films with a near zero net film stress and less than a 1% loss in reflectivity. For example a Mo/Be film with 68.7% reflectivity at 11.4 nm and a Mo/Si film with 66.5% reflectivity at 13.3 nm were produced with net stress values less than 30 MPa. digital.library.unt.edu/ark:/67531/metadc710268/
Advances in the simulation of toroidal gyro Landau fluid model turbulence
The gyro-Landau fluid (GLF) model equations for toroidal geometry have been recently applied to the study ion temperature gradient (ITG) mode turbulence using the 3D nonlinear ballooning mode representation (BMR). The present paper extends this work by treating some unresolved issues conceming ITG turbulence with adiabatic electrons. Although eddies are highly elongated in the radial direction long time radial correlation lengths are short and comparable to poloidal lengths. Although transport at vanishing shear is not particularly large, transport at reverse global shear, is significantly less. Electrostatic transport at moderate shear is not much effected by inclusion of local shear and average favorable curvature. Transport is suppressed when critical E{times}B rotational shear is comparable to the maximum linear growth rate with only a weak dependence on magnetic shear. Self consistent turbulent transport of toroidal momentum can result in a transport bifurcation at suffciently large r/(Rq). However the main thrust of the new formulation in the paper deals with advances in the development of finite beta GLF models with trapped electron and BMR numerical methods for treating the fast parallel field motion of the untrapped electrons. digital.library.unt.edu/ark:/67531/metadc688719/
Advances in the TOUGH2 family of general-purpose reservoir simulators
TOUGH2 is a general-purpose fluid and heat flow simulators, with applications in geothermal reservoir engineering, nuclear waste disposal, and environmental contamination problems. This report summarizes recent developments which enhance the usability of the code, and provide a more accurate and comprehensive description of reservoir processes. digital.library.unt.edu/ark:/67531/metadc666894/
Advances in the use of tomographic inspection techniques for non-destructive analysis of geometric conductor position and correlation with magnetic cross-section modeling
Industrial Computerized Tomography has been applied to magnet components in various stages of the manufacturing process. These Computerized Tomographic images can be analyzed to infer detailed dimensional information about magnet component positions (conductor, wedges, collars, etc.) throughout the magnet manufacturing process (cable winding, collaring, yoked/skinned). An analysis technique will be presented and measurement accuracies will be discussed. digital.library.unt.edu/ark:/67531/metadc712481/
Advances in tubular solid oxide fuel cell technology
This document provides the functional design criteria for an addition to the 222-S facility. This project will provide space for manipulator repair, equipment and manipulator decontamination and laundry storage. The manipulator repair and storage area will provide for storage of 20 manipulators, an area for receiving potentially contaminated manipulators and an area for the repair of manipulators. The decontamination area will be capable of decontamination of manipulators and shipping casks, pigs, T-handle carriers and other shipping containers. The laundry storage area will provide space for potentially contaminated and clean laundry. digital.library.unt.edu/ark:/67531/metadc688051/
Advances in welding science and technology
Over the years, welding has been more of an art than a science, but in the last few decades major advances have taken place in welding science and technology. With the development of new methodologies at the crossroads of basic and applied sciences, enormous opportunities and potential exist to develop a science-based design of composition, structure, and properties of welds with intelligent control and automation of the welding processes. In the last several decades, welding has evolved as an interdisciplinary activity requiring synthesis of knowledge from various disciplines and incorporating the most advanced tools of various basic applied sciences. A series of international conferences and other publications have covered the issues, current trends and directions in welding science and technology. In the last few decades, major progress has been made in (i) understanding physical processes in welding, (ii) characterization of microstructure and properties, and (iii) intelligent control and automation of welding. This paper describes some of these developments. digital.library.unt.edu/ark:/67531/metadc669614/
Advances in x-ray computed microtomography at the NSLS
The X-Ray Computed Microtomography workstation at beamline X27A at the NSLS has been utilized by scientists from a broad range of disciplines from industrial materials processing to environmental science. The most recent applications are presented here as well as a description of the facility that has evolved to accommodate a wide variety of materials and sample sizes. One of the most exciting new developments reported here resulted from a pursuit of faster reconstruction techniques. A Fast Filtered Back Transform (FFBT) reconstruction program has been developed and implemented, that is based on a refinement of the gridding algorithm first developed for use with radio astronomical data. This program has reduced the reconstruction time to 8.5 sec for a 929 x 929 pixel{sup 2} slice on an R10,000 CPU, more than 8x reduction compared with the Filtered Back-Projection method. digital.library.unt.edu/ark:/67531/metadc711142/
ADVANCES IN X-RAY COMPUTED MICROTOMOGRAPHY AT THE NSLS.
The X-Ray Computed Microtomography workstation at beamline X27A at the NSLS has been utilized by scientists from a broad range of disciplines from industrial materials processing to environmental science. The most recent applications are presented here as well as a description of the facility that has evolved to accommodate a wide variety of materials and sample sizes. One of the most exciting new developments reported here resulted from a pursuit of faster reconstruction techniques. A Fast Filtered Back Transform (FFBT) reconstruction program has been developed and implemented, that is based on a refinement of the ''gridding'' algorithm first developed for use with radio astronomical data. This program has reduced the reconstruction time to 8.5 sec for a 929 x 929 pixel{sup 2} slice on an R10,000 CPU, more than 8x reduction compared with the Filtered Back-Projection method. digital.library.unt.edu/ark:/67531/metadc625633/
ADVANCES IN YBCO COATED CONDUCTOR TECHNOLOGY
No abstract prepared. digital.library.unt.edu/ark:/67531/metadc719028/
Advancing Design-for-Assembly: The Next Generation in Assembly Planning
At the 1995 IEEE Symposium on Assembly and Task Planning, Sandia National Laboratories introduced the Archimedes 2 Software Tool [2]. The system was described as a second-generation assembly planning system that allowed preliminmy application of awembly planning for industry, while solidly supporting further research in planning techniques. Sandia has worked closely with indust~ and academia over the last four years. The results of these working relationships have bridged a gap for the next generation in assembly planning. Zke goal of this paper is to share Sandia 's technological advancements in assembly planning over the last four years and the impact these advancements have made on the manufacturing communip. digital.library.unt.edu/ark:/67531/metadc672724/
Advancing lighting and daylighting simulation: The transition from analysis to design aid tools
This paper explores three significant software development requirements for making the transition from stand-alone lighting simulation/analysis tools to simulation-based design aid tools. These requirements include specialized lighting simulation engines, facilitated methods for creating detailed simulatable building descriptions, an automated techniques for providing lighting design guidance. Initial computer implementations meant to address each of these requirements are discussed to further elaborate these requirements and to illustrate work-in-progress. digital.library.unt.edu/ark:/67531/metadc792891/
Advancing manufacturing through computational chemistry
The capabilities of nanotechnology and computational chemistry are reaching a point of convergence. New computer hardware and novel computational methods have created opportunities to test proposed nanometer-scale devices, investigate molecular manufacturing and model and predict properties of new materials. Experimental methods are also beginning to provide new capabilities that make the possibility of manufacturing various devices with atomic precision tangible. In this paper, we will discuss some of the novel computational methods we have used in molecular dynamics simulations of polymer processes, neural network predictions of new materials, and simulations of proposed nano-bearings and fluid dynamics in nano- sized devices. digital.library.unt.edu/ark:/67531/metadc670616/
Advancing precollege science and mathematics education in San Diego County. Progress report, March 1, 1995--June 30, 1996
This report discusses advancing precollege science and mathematics education in San Diego Count. Described in this report are: curriculum and teacher development; pre-tour material; facility tour; student workbook; evaluation and assessment; and internet access. digital.library.unt.edu/ark:/67531/metadc698162/
Advancing the Technology Base for High Temperature Hydrogen Membranes
High purity hydrogen is a critical component for at least two major industrial processes: 1) the refining of conventional steels and raw pig iron into low carbon steels and high purity iron used for high performance magnets in motors, generators, alternators, transformers, and etc.; and 2) refining metallurgical grade silicon to the high- purity, polycrystalline silicon used in fabricating single crystal silicon wafers for semiconductor manufacturing. In the process of producing low carbon iron products, CO and CO2 impurities prevent efficient removal of the carbon already in the raw iron. In the refining of metallurgical grade silicon, the presence of any impurity above the part-per- million level prevents the ultimate fabrication of the large scale single crystals that are essential to the semiconductor device. In a lesser magnitude role, high quality hydrogen is used in a variety of other processes, including specialty metals refining (e.g., iridium, osmium, palladium, platinum, and ruthenium) and R{ampersand}D in areas such as organic synthesis and development of certain types of fuel cells. In all of these applications, a high-temperature hydrogen membrane can provide a method for achieving a very high purity level of hydrogen in a manner that is more economical and/or more rugged than existing techniques. digital.library.unt.edu/ark:/67531/metadc695477/
Advancing the technology base for high-temperature membranes
This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). This project addresses the major issues confronting the implementation of high-temperature membranes for separations and catalysis. We are pursuing high-temperature membrane systems that can have a large impact for DOE and be industrially relevant. A major obstacle for increased use of membranes is that most applications require the membrane material to withstand temperatures above those acceptable for polymer-based systems. Advances made by this project have helped industry and DOE move toward high-temperature membrane applications to improve overall energy efficiency. digital.library.unt.edu/ark:/67531/metadc691951/
The advantages of evaporation of Hafnium in a reactive environment to manufacture high damage threshold multilayer coatings by electron-beam deposition
No abstract prepared. digital.library.unt.edu/ark:/67531/metadc781170/
The advantages of including professionals from different fields of study in the solution of today`s water-related problems
This report presents the details of a meeting of the American Society of Civil Engineers pertaining to water resources and quality. This report suggests an interdisciplinary approach to solving today`s problems dealing with water resources. digital.library.unt.edu/ark:/67531/metadc706596/
Advantages of traveling wave resonant antennas for fast wave heating systems
The resilience of a maximally flat externally coupled traveling wave antenna (TWA) is contrasted with the sensitivity of a simple directly driven resonant loop array to vacuum and plasma conditions in DIII-D. We find a unique synergy between standing and traveling wave resonant TWA components. This synergy extends TWA operation to several passbands between 60 and 120 MHZ, provides 60{degrees}- 120{degrees} tunability between elements within a 1-2 MHZ bandwidth and permits efficient and continuous operation during ELMing H-mode. digital.library.unt.edu/ark:/67531/metadc674952/
Advantages of using a mirror as the first optical component for APS undulator beamlines
The advantages of using a mirror as the first optical component for an APS undulator beamline for thermal management, radiation shielding mitigation, and harmonic rejection are presented. digital.library.unt.edu/ark:/67531/metadc672791/
Adventures in Supercomputing: An innovative program
Within the realm of education, seldom does an innovative program become available with the potential to change an educator`s teaching methodology and serve as a spur to systemic reform. The Adventures in Supercomputing (AiS) program, sponsored by the Department of Energy, is such a program. Adventures in Supercomputing is a program for high school and middle school teachers. It has helped to change the teaching paradigm of many of the teachers involved in the program from a teacher-centered classroom to a student-centered classroom. ``A student-centered classroom offers better opportunities for development of internal motivation, planning skills, goal setting and perseverance than does the traditional teacher-directed mode``. Not only is the process of teaching changed, but evidences of systemic reform are beginning to surface. After describing the program, the authors discuss the teaching strategies being used and the evidences of systemic change in many of the AiS schools in Tennessee. digital.library.unt.edu/ark:/67531/metadc736601/
Adventures in supercomputing: An innovative program for high school teachers
Within the realm of education, seldom does an innovative program become available with the potential to change an educator`s teaching methodology. Adventures in Supercomputing (AiS), sponsored by the U.S. Department of Energy (DOE), is such a program. It is a program for high school teachers that changes the teacher paradigm from a teacher-directed approach of teaching to a student-centered approach. {open_quotes}A student-centered classroom offers better opportunities for development of internal motivation, planning skills, goal setting and perseverance than does the traditional teacher-directed mode{close_quotes}. Not only is the process of teaching changed, but the cross-curricula integration within the AiS materials is remarkable. Written from a teacher`s perspective, this paper will describe the AiS program and its effects on teachers and students, primarily at Wartburg Central High School, in Wartburg, Tennessee. The AiS program in Tennessee is sponsored by Oak Ridge National Laboratory (ORNL). digital.library.unt.edu/ark:/67531/metadc669051/
Adventures in supercomputing: Scientific exploration in an era of change
Students deserve the opportunity to explore the world of science surrounding them. Therefore it is important that scientific exploration and investigation be a part of each student`s educational career. The Department of Energy`s Adventures in Superconducting (AiS) takes students beyond mere scientific literacy to a rich embodiment of scientific exploration. AiS provides today`s science and math students with a greater opportunity to investigate science problems, propose solutions, explore different methods of solving the problem, organize their work into a technical paper, and present their results. Students learn at different rates in different ways. Science classes with students having varying learning styles and levels of achievement have always been a challenge for teachers. The AiS {open_quotes}hands-on, minds-on{close_quotes} project-based method of teaching science meets the challenge of this diversity heads on! AiS uses the development of student chosen projects as the means of achieving a lifelong enthusiasm for scientific proficiency. One goal of AiS is to emulate the research that takes place in the everyday environment of scientists. Students work in teams and often collaborate with students nationwide. With the help of mentors from the academic and scientific community, students pose a problem in science, investigate possible solutions, design a mathematical and computational model for the problem, exercise the model to achieve results, and evaluate the implications of the results. The students then have the opportunity to present the project to their peers, teachers, and scientists. Using this inquiry-based technique, students learn more than science skills, they learn to reason and think -- going well beyond the National Science Education Standard. The teacher becomes a resource person actively working together with the students in their quest for scientific knowledge. digital.library.unt.edu/ark:/67531/metadc697091/
Adverse Reactions to HIV Vaccines: Medical, Ethical, and Legal Issues
The purpose of this background paper is to describe the current state of development of HIV vaccines, and to discuss what is known about adverse reactions that may occur. The background paper provides an overview of ethical issues that arise in the conduct of HIV vaccine trials. The report also discusses alternatives to the current product liability system to encourage the development of HIV vaccines and to fairly compensate those who are harmed as a result of adverse reactions to the vaccine. digital.library.unt.edu/ark:/67531/metadc39788/
Advice and recommendations to the US Department of Energy in response to the charge letter of September 20, 1996
In Jan. 1996, the Fusion Energy Advisory Committee (FEAC) provided recommendations to DOE on how to restructure the fusion program in light of compressional guidance and budget realities. DOE endorsed these recommendations and prepared a strategic plan. The FEAC report concluded that the goals of the restructured program could most effectively be accomplished at a funding level of $275 million per year, including Federal government management costs. DOE requested that Congress appropriate $255.6 million in FY97 for the fusion energy sciences program exclusive of Federal government management costs (about $8 million). On Sept. 11, 1996, the Energy and Water Development Conference Committee settled on a FY97 appropriation for the fusion energy sciences program of $232.5 million. This report contains the response to the charge letter, on how the program described in the strategic plan could be changed to make it consistent with the $232.5 million appropriation. digital.library.unt.edu/ark:/67531/metadc677358/
Advisor 2.0: A Second-Generation Advanced Vehicle Simulator for Systems Analysis
The National Renewable Energy Laboratory has recently publicly released its second-generation advanced vehicle simulator called ADVISOR 2.0. This software program was initially developed four years ago, and after several years of in-house usage and evolution, the tool is now available to the public through a new vehicle systems analysis World Wide Web page. ADVISOR has been applied to many different systems analysis problems, such as helping to develop the SAE J1711 test procedure for hybrid vehicles and helping to evaluate new technologies as part of the Partnership for a New Generation of Vehicles (PNGV) technology selection process. The model has been and will continue to be benchmarked and validated with other models and with real vehicle test data. After two months of being available on the Web, more than 100 users have downloaded ADVISOR. ADVISOR 2.0 has many new features, including an easy-to-use graphical user interface, a detailed exhaust aftertreatment thermal model, and complete browser-based documentation. Future work will include adding to the library of components available in ADVISOR, including optimization functionality, and linking with a more detailed fuel cell model. digital.library.unt.edu/ark:/67531/metadc690816/
Advisory Committee on human radiation experiments final report
When the Advisory Committee began work in April 1994 we were charged with determining whether the radiation experiments design and administration adequately met the ethical and scientific standards, including standards of informed consent, that prevailed at the time of the experiments and that exist today and also to determine the ethical and scientific standards and criteria by which it shall evaluate human radiation experiments. Although this charge seems straightforward, it is in fact difficult to determine what the appropriate standards should be for evaluating the conduct and policies of thirty or fifty years ago. First, we needed to determine the extent to which the standards of that time are similar to the standards of today. To the extent that there were differences we needed to determine the relative roles of each in making moral evaluations. In Chapter 1 we report what we have been able to reconstruct about government rules and policies in the 1940s and 1950s regarding human experiments. We focus primarily on the Atomic Energy Commission and the Department of Defense. In Chapter 2 we turn from a consideration of government standards to an exploration of the norms and practices of physicians and medical scientists who conducted research with human subjects during this period. Using the results of our Ethics Oral History Project, and other sources, we also examine how scientists of the time viewed their moral responsibilities to human subjects as well as how this translated into the manner in which they conducted their research. digital.library.unt.edu/ark:/67531/metadc621845/
Advisory Committee on human radiation experiments. Final report, Supplemental Volume 2. Sources and documentation
This volume and its appendixes supplement the Advisory Committee`s final report by reporting how we went about looking for information concerning human radiation experiments and intentional releases, a description of what we found and where we found it, and a finding aid for the information that we collected. This volume begins with an overview of federal records, including general descriptions of the types of records that have been useful and how the federal government handles these records. This is followed by an agency-by-agency account of the discovery process and descriptions of the records reviewed, together with instructions on how to obtain further information from those agencies. There is also a description of other sources of information that have been important, including institutional records, print resources, and nonprint media and interviews. The third part contains brief accounts of ACHRE`s two major contemporary survey projects (these are described in greater detail in the final report and another supplemental volume) and other research activities. The final section describes how the ACHRE information-nation collections were managed and the records that ACHRE created in the course of its work; this constitutes a general finding aid for the materials deposited with the National Archives. The appendices provide brief references to federal records reviewed, descriptions of the accessions that comprise the ACHRE Research Document Collection, and descriptions of the documents selected for individual treatment. Also included are an account of the documentation available for ACHRE meetings, brief abstracts of the almost 4,000 experiments individually described by ACHRE staff, a full bibliography of secondary sources used, and other information. digital.library.unt.edu/ark:/67531/metadc624150/
Advisory Committee on human radiation experiments. Supplemental, Volume 1, Ancillary materials. Final report
This report is a large collection of contemporary documents pertaining to the consideration of ethical and legal aspects of use of human beings in medical and experimental studies. digital.library.unt.edu/ark:/67531/metadc621280/
Advisory Committee on human radiation experiments. Supplemental Volume 2a, Sources and documentation appendices. Final report
This large document provides a catalog of the location of large numbers of reports pertaining to the charge of the Presidential Advisory Committee on Human Radiation Research and is arranged as a series of appendices. Titles of the appendices are Appendix A- Records at the Washington National Records Center Reviewed in Whole or Part by DoD Personnel or Advisory Committee Staff; Appendix B- Brief Descriptions of Records Accessions in the Advisory Committee on Human Radiation Experiments (ACHRE) Research Document Collection; Appendix C- Bibliography of Secondary Sources Used by ACHRE; Appendix D- Brief Descriptions of Human Radiation Experiments Identified by ACHRE, and Indexes; Appendix E- Documents Cited in the ACHRE Final Report and other Separately Described Materials from the ACHRE Document Collection; Appendix F- Schedule of Advisory Committee Meetings and Meeting Documentation; and Appendix G- Technology Note. digital.library.unt.edu/ark:/67531/metadc620975/
AEA Fluidic Pulse Jet Mixer. Innovative Technology Summary Report
AEA's Fluidic Pulse Jet Mixer was developed to mix and maintain the suspension of solids and to blend process liquids. The mixer can be used to combine a tank's available supernate with the sludge into a slurry that is suitable for pumping. The system uses jet nozzles in the tank coupled to a charge vessel. Then, a jet pump creates a partial vacuum in the charge vessel allowing it to be filled with waste. Next, air pressure is applied to the charge vessel, forcing sludge back into the tank and mixing it with the liquid waste. When the liquid waste contains 10% solids, a batch is pumped out of the tank. digital.library.unt.edu/ark:/67531/metadc716945/
The Aegis initiative: An integrated, real-time, environmental monitoring and response management capability. Final report
The Aegis system at Lawrence Livermore National Laboratory (LLNL) is being developed to provide a real-time emergency response management capability for a diverse range of environmental monitoring applications. The Aegis system is designed to integrate a variety of environmental, emergency, and process monitoring sensor systems using a flexible, modular architecture that can be readily configured for any number of industrial, commercial, or government sites. Several unique LLNL technologies are being integrated via this effort that will provide tracking of environmental contaminants, real-time identification of potentially unacceptable conditions, and facilitation of emergency or measured response management operations. Potential areas of application include: monitoring-surface/ground water, air, radiation; waste effluent & storm/drain line; water quality (water storage, treatment, and distribution); fixed processes, safety systems; critical facilities; hazardous spill management; rapid environmental monitoring deployment; watershed protection; ecosystem management and restoration; enforcement and compliance. digital.library.unt.edu/ark:/67531/metadc785371/
AEM investigation of tetrahedrally coordinated Ti{sup 4+} in nickel-titanate spinel
Stoichiometry and site distribution of metastable nickel-titanate spinel was studied with AEM. Results of EDXS and EELS agree that the metastable spinel is nonstoichiometric and titanium-deficient relative to its hypothetical endmember composition, ``Ni{sub 2}TiO{sub 4}``. The titanium deficiency has been determined by EELS to be {Delta} = 0.025 {plus_minus} 0.005. Channeling-enhanced microanalysis and ELNES studies indicate that the Ti{sup 4+} and Ni{sup 2+} cations are in tetrahedral and octahedral coordination, respectively, so that the metastable spinel has the normal cation distribution: Ti{sub l-{Delta}}[Ni{sub 2(1+{Delta})}]O{sub 4}. This is consistent with neutron powder-diffraction studies and SiO{sub 2}-solubility measurements of similar equilibrated and quenched spinel-containing specimens. Metastable nickel-titanate spinel therefore contrasts with stable stoichiometric spinels which tend to the inverse cation distribution, Me[MeTi]O{sub 4}. digital.library.unt.edu/ark:/67531/metadc669904/
AEM investigations of primary water SCC in nickel alloys
The microstructure of nickel alloys, particularly the grain boundary composition and intergranular precipitates, plays an important role in high temperature primary water stress corrosion cracking (SCC) performance. Analytical electron microscopy (AEM) was used to examine SCC cracks in Alloys 600 and X-750 to investigate the role of grain boundary precipitates, dislocations and oxides in primary water SCC (PWSCC). Analysis of oxides by AEM and ESCA/Auger indicates that the crack tip oxides are different than the oxides formed on the outer surfaces. Comparison of heats with good and poor SCC resistance has identified metallurgical features that affect cracking. These AEM results show that the mechanism of PWSCC in nickel-base alloys does not involve void formation or blunting of the crack tip near intergranular carbides. The role of grain boundary composition, the interaction of cracks with carbides and other intergranular precipitates, and observations from AEM examinations ahead of the crack tip are discussed in relation to the mechanism of SCC. digital.library.unt.edu/ark:/67531/metadc680023/
Aerial and ground-based inspections of mine sites in the Western U.S.-implications for on-site inspection overflights, under the CTBT
The verification regime of the Comprehensive Test Ban Treaty (CTBT) provides for the possibility of On-Site Inspections (OSI`s) to resolve questions concerning suspicious events which may have been clandestine nuclear tests. Overflights by fixed-wing or rotary-wing aircraft, as part of an OSI, are permitted by the Treaty. These flights are intended to facilitate the narrowing of the inspection area, from an initial permissible 1000 km{sup 2}, and to help select the locations to deploy observers and ground-based sensors (seismic, radionuclides, . . .) Because of the substantial amount of seismicity generated by mining operations worldwide, it is expected that mine sites and mine districts would be prime candidates for OSI`S. To gain experience in this context, a number of aerial and ground-based mine site inspections have been performed in the Western U.S. by Lawrence Livermore National Laboratory since 1994. These inspections are part of a broad range of CTBT mining-related projects conducted by the U.S. Department of Energy and its National Laboratories. The various sites are described next, and inferences are made concerning CTBT OSI`S. All the mines are legitimate operations, with no implication whatsoever of any clandestine tests. digital.library.unt.edu/ark:/67531/metadc696390/
An aerial multispectral thermographic survey of the Oak Ridge Reservation for selected areas K-25, X-10, and Y-12, Oak Ridge, Tennessee
During June 5-7, 1996, the Department of Energy`s Remote Sensing Laboratory performed day and night multispectral surveys of three areas at the Oak Ridge Reservation: K-25, X-10, and Y-12. Aerial imagery was collected with both a Daedalus DS1268 multispectral scanner and National Aeronautics and Space Administration`s Thermal Infrared Multispectral System, which has six bands in the thermal infrared region of the spectrum. Imagery from the Thermal Infrared Multispectral System was processed to yield images of absolute terrain temperature and of the terrain`s emissivities in the six spectral bands. The thermal infrared channels of the Daedalus DS1268 were radiometrically calibrated and converted to apparent temperature. A recently developed system for geometrically correcting and geographically registering scanner imagery was used with the Daedalus DS1268 multispectral scanner. The corrected and registered 12-channel imagery was orthorectified using a digital elevation model. 1 ref., 5 figs., 5 tabs. digital.library.unt.edu/ark:/67531/metadc676996/
Aerial oxidation of tetraethyl silicate and effect on ammonia catalyzed hydrolysis
Colloidal suspensions of Si0{sub 2} in ethanol prepared by the ammonia catalyzed hydrolysis of tetraethyl silicate (TEOS) in ethanol have been routinely used for over 10 years to prepare antireflective (AR) coatings on the fused silica transmissive optical components of high power fusion lasers. Very high purity coatings are required to avoid laser damage and these are obtained when the TEOS is fractionally distilled under N{sub 2} prior to use. Recently we found that products from aerial oxidation of distilled TEOS, had a significant effect on the particle size of our coating suspensions to the detriment of the optical performance. We require particle sizes less than 20 nm to avoid light loss due to scatter and contaminated TEOS gave suspensions with much higher particle sizes. Oxidation products were identified by GC mass spectroscopy and included acetaldehyde, acetic acid, silicon acetates and reaction products of these compounds with ethanol. Acetic acid and silicon acetates were found to be the major cause of large particle formation. These could be removed by careful redistillation preferably in the presence of a small quantity of magnesium ethoxide. Storage in sealed containers over N{sub 2} avoided further problems. digital.library.unt.edu/ark:/67531/metadc692668/
Aerial photographic interpretation of lineaments and faults in late cenozoic deposits in the Eastern part of the Benton Range 1:100,000 quadrangle and the Goldfield, Last Chance Range, Beatty, and Death Valley Junction 1:100,000 quadrangles, Nevada and California
Lineaments and faults in Quaternary and late Tertiary deposits in the southern part of the Walker Lane are potentially active and form patterns that are anomalous with respect to the typical fault patterns in most of the Great Basin. Little work has been done to identify and characterize these faults, with the exception of those in the Death Valley-Furnace Creek (DVFCFZ) fault system and those in and near the Nevada Test Site. Four maps at a scale of 1:100,000 summarize the existing knowledge about these lineaments and faults based on extensive aerial-photo interpretation, limited field investigations, and published geologic maps. The lineaments and faults in all four maps can be divided geographically into two groups. The first group includes west- to north-trending lineaments and faults associated with the DVFCFZ and with the Pahrump fault zone in the Death Valley Junction quadrangle. The second group consists of north- to east-northeast-trending lineaments and faults in a broad area that lies east of the DVFCFZ and north of the Pahrump fault zone. Preliminary observations of the orientations and sense of slip of the lineaments and faults suggest that the least principle stress direction is west-east in the area of the first group and northwest-southeast in the area of the second group. The DVFCFZ appears to be part of a regional right-lateral strike-slip system. The DVFCFZ steps right, accompanied by normal faulting in an extensional zone, to the northern part of the Walker Lane a the northern end of Fish Lake Valley (Goldfield quadrangle), and appears to step left, accompanied by faulting and folding in a compressional zone, to the Pahrump fault zone in the area of Ash Meadows (Death Valley Junction quadrangle). 25 refs. digital.library.unt.edu/ark:/67531/metadc628610/
Aerial photographic interpretation of lineaments and faults in late Cenozoic deposits in the eastern parts of the Saline Valley 1:100, 000 quadrangle, Nevada and California, and the Darwin Hills 1:100, 000 quadrangle, California
Faults and fault-related lineaments in Quaternary and late Tertiary deposits in the southern part of the Walker Lane are potentially active and form patterns that are anomalous compared to those in most other areas of the Great Basin. Two maps at a scale of 1:100,000 summarize information about lineaments and faults in the area around and southwest of the Death Valley-Furnace Creek fault system based on extensive aerial-photo interpretation, limited field interpretation, limited field investigations, and published geologic maps. There are three major fault zones and two principal faults in the Saline Valley and Darwin Hills 1:100,000 quadrangles. (1) The Death Valley-Furnace Creek fault system and (2) the Hunter Mountain fault zone are northwest-trending right-lateral strike-slip fault zones. (3) The Panamint Valley fault zone and associated Towne Pass and Emigrant faults are north-trending normal faults. The intersection of the Hunter Mountain and Panamint Valley fault zones is marked by a large complex of faults and lineaments on the floor of Panamint Valley. Additional major faults include (4) the north-northwest-trending Ash Hill fault on the west side of Panamint Valley, and (5) the north-trending range-front Tin Mountain fault on the west side of the northern Cottonwood Mountains. The most active faults at present include those along the Death Valley-Furnace Creek fault system, the Tin Mountain fault, the northwest and southeast ends of the Hunter Mountain fault zone, the Ash Hill fault, and the fault bounding the west side of the Panamint Range south of Hall Canyon. Several large Quaternary landslides on the west sides of the Cottonwood Mountains and the Panamint Range apparently reflect slope instability due chiefly to rapid uplift of these ranges. 16 refs. digital.library.unt.edu/ark:/67531/metadc619289/
Aerial Radiation Detection
An airborne system designed for the detection of radioactive sources on the soil surface from an aircraft normally senses gamma rays emitted by the source. Gamma rays have the longest path length (least attenuation) through the air of any of the common radioactive emissions and will thus permit source detection at large distances. A secondary benefit from gamma rays detection if that nearly all radioactive isotopes can be identified by the spectrum of gammas emitted. Major gaseous emissions from fuel processing plants emit gammas that may be detected and identified. Some types of special nuclear material also emit neutrons which are also useful for detection at a distance. digital.library.unt.edu/ark:/67531/metadc619537/
An aerial radiological survey of Frenchman Flat at the Nevada Test Site, Southern Nevada
An aerial radiological survey was conducted over Frenchman Flat at the Nevada Test Site from January 27 to February 7,1982. Parallel lines were flown at an altitude of 100 feet (30 meters) above ground level with line spacing intervals of 200 feet (61 meters) over a 170-square-mile (440-square-kilometer) area. This covered both Frenchman Flat and the area of the Nellis Range Complex where a fallout deposition plume had exited the Nevada Test Site to the east. The aerial data obtained were reduced to a man-made radiation contour map and overlaid on a U.S. Geological Survey map. The survey detected the presence of fission and activation products. 4 refs., 3 figs., 1 tab. digital.library.unt.edu/ark:/67531/metadc687455/
An aerial radiological survey of Project Gasbuggy and surrounding area, Rio Arriba County, New Mexico. Date of survey: October 27, 1994
An aerial radiological survey was conducted over the Project Gasbuggy site, 55 miles (89 kilometers) east of Farmington, New Mexico, on October 27, 1994. Parallel lines were flown at intervals of 300 feet (91 meters) over a 16-square-mile (41-square-kilometer) area at a 150-foot (46-meter) altitude centered on the Gasbuggy site. The gamma energy spectra obtained were reduced to an exposure rate contour map overlaid on a high altitude aerial photograph of the area. The terrestrial exposure rate varied from 14 to 20 {micro}R/h at 1 meter above ground level. No anomalous or man-made isotopes were found. digital.library.unt.edu/ark:/67531/metadc628176/
An aerial radiological survey of Project Rulison and surrounding area, Battlement Creek Valley, Colorado
An aerial radiological survey was conducted over the Project Rulison site, 40 miles (64 kilometers) northeast of Grand Junction, Colorado, from July 6 through July 12, 1993. Parallel lines were flown at intervals of 250 feet (76 meters) over a 6.5-square-mile (17-square-kilometer) area at a 200-foot (61-meter) altitude surrounding Battlement Creek Valley. The gamma energy spectra obtained were reduced to an exposure rate contour map overlaid on a high altitude aerial photograph of the area. The terrestrial exposure rate varied from 3.5 to 12.5 {mu}R/h (excluding cosmic) at 1 meter above ground level. No anomalous or man-made isotopes were found. digital.library.unt.edu/ark:/67531/metadc625596/
An aerial radiological survey of the Davis-Monthan Air Force Base and surrounding area, Tucson, Arizona
An aerial radiological survey, which was conducted from March 1 to 13, 1995, covered a 51-square-mile (132-square-kilometer) area centered on the Davis-Monthan Air Force Base (DMAFB) in Tucson, Arizona. The results of the survey are reported as contours of bismuth-214 ({sup 214}Bi) soil concentrations, which are characteristic of natural uranium and its progeny, and as contours of the total terrestrial exposure rates extrapolated to one meter above ground level. All data were scaled and overlaid on an aerial photograph of the DMAFB area. The terrestrial exposure rates varied from 9 to 20 microroentgens per hour at one meter above the ground. Elevated levels of terrestrial radiation due to increased concentrations of {sup 214}Bi (natural uranium) were observed over the Southern Pacific railroad yard and along portions of the railroad track bed areas residing both within and outside the base boundaries. No man-made, gamma ray-emitting radioactive material was observed by the aerial survey. High-purity germanium spectrometer and pressurized ionization chamber measurements at eight locations within the base boundaries were used to verify the integrity of the aerial results. The results of the aerial and ground-based measurements were found to be in agreement. However, the ground-based measurements were able to detect minute quantities of cesium-137 ({sup 137}Cs) at six of the eight locations examined. The presence of {sup 137}Cs is a remnant of fallout from foreign and domestic atmospheric nuclear weapons testing that occurred in the 1950s and early 1960s. Cesium-137 concentrations varied from 0.1 to 0.3 picocuries per gram, which is below the minimum detectable activity of the aerial system. digital.library.unt.edu/ark:/67531/metadc622013/
An aerial radiological survey of the Double Track Site and surrounding area. Central Nevada
An aerial radiological survey of the Double Track Site was conducted in December 1993. An interim report was issued. That report described survey procedures and presented terrestrial exposure rate and wide-area-averaged plutonium isopleth plots. This letter report presents additional plutonium plots and some ``rule-of-thumb`` calculations which should help the reader to properly interpret the data presented. Attached to this report are three isopleth plots produced from the Double Track data. No one processing method provides all the answers regarding a particular surveyed area. Where peak values are most important, isopleth {number_sign}1, created from the original unsmoothed data, is the presentation of choice. Isopleth {number_sign}2, from smoothed data, is superior for the detection of areas of widespread low-level contamination. Isopleth {number_sign}3, also smoothed data, satisfied a particular early mission goal but is not as useful for cleanup operations as the other two. digital.library.unt.edu/ark:/67531/metadc665394/
An aerial radiological survey of the Double Track Site and surrounding area, Central Nevada. Date of survey: December 1993
An aerial radiological survey of the Double Track Site was conducted in December 1993. An interim report described survey procedures and presented terrestrial exposure rate and wide-area-averaged plutonium isopleth plots. This letter report presents additional plutonium plots and some rule-of-thumb calculations which should help the reader to properly interpret the data presented. Attached to this report are three isopleth plots produced from the Double Track data. No one processing method provides all the answers regarding a particular surveyed area. Where peak vales are most important, a figure created from the original unsmoothed data is the presentation of choice. A figure from smoothed data is superior for the detection of areas of widespread low-level contamination. A figure , also smoothed data, satisfied a particular early mission goal but is not as useful for cleanup operations as the other two. This last figure is presented for historical completeness only. digital.library.unt.edu/ark:/67531/metadc622936/
An aerial radiological survey of the Fernald Environmental Management Project and surrounding area, Fernald, Ohio
An aerial radiological survey was conducted from May 17--22, 1994, over a 36 square mile (93 square kilometer) area centered on the Fernald Environmental Management Project located in Fernald, Ohio. The purpose of the survey was to detect anomalous gamma radiation in the environment surrounding the plant. The survey was conducted at a nominal altitude of 150 feet (46 meters) with a line spacing of 250 feet (76 meters). A contour map of the terrestrial gamma exposure rate extrapolated to 1 meter (3.3 feet) above ground was prepared and overlaid on an aerial photograph of the area. Analysis of the data for man made sources showed five sites within the boundaries of the Fernald Environmental Management Project having elevated readings. The exposure rates outside the plant boundary were typical of naturally occurring background radiation. Soil samples and pressurized ion chamber measurements were obtained at four locations within the survey boundaries to supplement the aerial data. It was concluded that although the radionuclides identified in the high-exposure-rate areas are naturally occurring, the levels encountered are greatly enhanced due to industrial activities at the plant. digital.library.unt.edu/ark:/67531/metadc709545/
An aerial radiological survey of the Nevada Test Site
A team from the Remote Sensing Laboratory conducted an aerial radiological survey of the US Department of Energy's Nevada Test Site including three neighboring areas during August and September 1994. The survey team measured the terrestrial gamma radiation at the Nevada Test Site to determine the levels of natural and man-made radiation. This survey included the areas covered by previous surveys conducted from 1962 through 1993. The results of the aerial survey showed a terrestrial background exposure rate that varied from less than 6 microroentgens per hour (mR/h) to 50 mR/h plus a cosmic-ray contribution that varied from 4.5 mR/h at an elevation of 900 meters (3,000 feet) to 8.5 mR/h at 2,400 meters (8,000 feet). In addition to the principal gamma-emitting, naturally occurring isotopes (potassium-40, thallium-208, bismuth-214, and actinium-228), the man-made radioactive isotopes found in this survey were cobalt-60, cesium-137, europium-152, protactinium-234m an indicator of depleted uranium, and americium-241, which are due to human actions in the survey area. Individual, site-wide plots of gross terrestrial exposure rate, man-made exposure rate, and americium-241 activity (approximating the distribution of all transuranic material) are presented. In addition, expanded plots of individual areas exhibiting these man-made contaminations are given. A comparison is made between the data from this survey and previous aerial radiological surveys of the Nevada Test Site. Some previous ground-based measurements are discussed and related to the aerial data. In regions away from man-made activity, the exposure rates inferred from the gamma-ray measurements collected during this survey agreed very well with the exposure rates inferred from previous aerial surveys. digital.library.unt.edu/ark:/67531/metadc708016/