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340 waste handling facility interim safety basis (open access)

340 waste handling facility interim safety basis

This document presents an interim safety basis for the 340 Waste Handling Facility classifying the 340 Facility as a Hazard Category 3 facility. The hazard analysis quantifies the operating safety envelop for this facility and demonstrates that the facility can be operated without a significant threat to onsite or offsite people.
Date: April 1, 1999
Creator: VAIL, T.S.
System: The UNT Digital Library
1998 Laboratory Directed Research and Development Annual Report (open access)

1998 Laboratory Directed Research and Development Annual Report

This reports summarizes progress from the Laboratory Directed Research and Development (LDRD) program during fiscal year 1998.
Date: April 1, 1999
Creator: Chavez, D. & Meyers, C.E.
System: The UNT Digital Library
Ab initio calculations of As-vacancy interactions in silicon (open access)

Ab initio calculations of As-vacancy interactions in silicon

Atomistic simulation of a vacancy-assisted dopant diffusion in silicon needs details of the dopant-vacancy interaction, i.e., the potential as a functional of dopant-vacancy separations. In this paper, the authors present a detailed study on the energetics of As-vacancy reaction in silicon and the lattice distortions surrounding the As-vacancy defect by using an ab initio plane wave pseudopotential method and the density functional theory (DFT). A potential-energy diagram as a function of As-vacancy separation is provided, which can be used in the atomistic diffusion simulations. The authors also calculate the binding energy and the formation energy of different complexes such as AsV, As{sub 2}V and AsV{sub 2} (V represents vacancy). They find that the stable configuration of As{sub 2}V is As-V-As, while the stable configuration of AsV{sub 2} is As-V-V. The nature of the binding between As and vacancy is explained from the lattice distortions and the change of chemical bond configuration introduced by the As-vacancy complex.
Date: April 1, 1999
Creator: Xie, J. & Chen, S. P.
System: The UNT Digital Library
Advanced Concepts for High-Power VCSELS and 2-Dimensional VCSEL Arrays (open access)

Advanced Concepts for High-Power VCSELS and 2-Dimensional VCSEL Arrays

We have developed high power vertical cavity surface emitting lasers (VCSELS) for multimode or single mode operation. We have characterized new cavity designs for individual lasers and 2-dimensional VCSEL arrays to maximize output power. Using broad area high power VCSELS under pulsed excitation, we have demonstrated the triggering of a photoconductive semiconductor switch (PCSS) with a VCSEL. We also have developed designs for high output power in a single mode. The first approach is to engineer the oxide aperture profile to influence the optical confinement and thus modal properties. A second approach focuses on "leaky-mode" concepts using lateral modification of the cavity resonance to provide the lateral refractive index difference. To this end, we have developed a regrowth process to fabricate single-mode VCSELS. The overall objective of this work was to develop high-power single-mode or multimode sources appropriate for many applications leveraging the many inherent advantages of VCSELS.
Date: April 1, 1999
Creator: Allerman, A. A.; Choquette, Kent D.; Chow, W. W.; Geib, K. M.; Hadley, R.; Hou, H. Q. et al.
System: The UNT Digital Library
ADVANCED GAS TURBINE SYSTEMS RESEARCH (open access)

ADVANCED GAS TURBINE SYSTEMS RESEARCH

None
Date: April 1, 1999
Creator: unknown
System: The UNT Digital Library
ADVANCED HOT GAS FILTER DEVELOPMENT (open access)

ADVANCED HOT GAS FILTER DEVELOPMENT

Iron aluminide hot gas filters have been developed using powder metallurgy techniques to form seamless cylinders. Three alloys were short-term corrosion tested in simulated IGCC atmospheres with temperatures between 925 F and 1200 F with hydrogen sulfide concentrations ranging from 783 ppm{sub v} to 78,300 ppm{sub v}. Long-term testing was conducted for 1500 hours at 925 F with 78,300 ppm{sub v}. The FAS and FAL alloys were found to be corrosion resistant in the simulated environments. The FAS alloy has been commercialized.
Date: April 1, 1999
Creator: June, Matthew R.; Hurley, John L. & Johnson, Mark W.
System: The UNT Digital Library
ADVANCED HYBRID PARTICULATE COLLECTOR (open access)

ADVANCED HYBRID PARTICULATE COLLECTOR

A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the U.S. Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in a manner that has not been done before. The AHPC concept consists of a combination of fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two collection methods, both in the particulate collection step and in transfer of the dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emission with conventional ESPs, and it solves the problem of reentrainment and collection of dust in conventional baghouses.
Date: April 1, 1999
Creator: Miller, Stanley J. & Schelkoph, Grant L.
System: The UNT Digital Library
ADVANCED SULFUR CONTROL CONCEPTS FOR HOT GAS DESULFURIZATION TECHNOLOGY (open access)

ADVANCED SULFUR CONTROL CONCEPTS FOR HOT GAS DESULFURIZATION TECHNOLOGY

The objective of this project is to develop a hot-gas desulfurization process scheme for control of H{sub 2}S in HTHP coal gas that can be more simply and economically integrated with known regenerable sorbents in DOE/METC-sponsored work than current leading hot-gas desulfurization technologies. In addition to being more economical, the process scheme to be developed must yield an elemental sulfur byproduct.
Date: April 1, 1999
Creator: unknown
System: The UNT Digital Library
Airborne Effluent Monitoring System Certification for New Canister Storage Building Ventilation Exhaust Stack (open access)

Airborne Effluent Monitoring System Certification for New Canister Storage Building Ventilation Exhaust Stack

Pacific Northwest National Laboratory conducted three of the six tests needed to verify that the effluent monitoring system for the new Canister Storage Building ventilation exhaust stack meets applicable regulatory performance criteria for air sampling systems at nuclear facilities. These performance criteria address both the suitability of the location for the air-sampling probe and the transport of the sample to the collection devices. The criteria covering the location for the air-sampling probe ensure that the contaminants in the stack are well mixed with the airflow at the probe location such that the extracted sample represents the whole. The sample-transport criteria ensure that the sampled contaminants are quantitatively delivered to the collection device. The specific performance criteria are described in detail in this report. The tests reported here cover the contaminant tracer uniformity and particle delivery performance criteria. These criteria were successfully met. The other three tests were conducted by the start-up staff of Duke Engineering and Services Hanford Inc. (DESH) and reported elsewhere. The Canister Storage Building is located in the 200 East Area of the U.S. Department of Energy's Hanford Site near Richland, Washington. The new air-exhaust system was built under the W379 Project. The air sampling system features …
Date: April 1, 1999
Creator: Glissmeyer, J. A. & Maughan, A. D.
System: The UNT Digital Library
ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS (open access)

ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS

The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.
Date: April 1, 1999
Creator: unknown
System: The UNT Digital Library
ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS. FINAL QUARTERLY STATUS REPORT (open access)

ALTERNATIVE FUELS AND CHEMICALS FROM SYNTHESIS GAS. FINAL QUARTERLY STATUS REPORT

The overall objectives of this program are to investigate potential technologies for the conversion of synthesis gas to oxygenated and hydrocarbon fuels and industrial chemicals, and to demonstrate the most promising technologies at DOE's LaPorte, Texas, Slurry Phase Alternative Fuels Development Unit (AFDU). The program will involve a continuation of the work performed under the Alternative Fuels from Coal-Derived Synthesis Gas Program and will draw upon information and technologies generated in parallel current and future DOE-funded contracts.
Date: April 1, 1999
Creator: unknown
System: The UNT Digital Library
An Annotated Reference Guide to the Finite-Element Interface Specification Version 1.0 (open access)

An Annotated Reference Guide to the Finite-Element Interface Specification Version 1.0

The Finite-Element Interface (FEI) specification provides a layered abstraction that permits finite-element analysis codes to utilize various linear-algebra solution packages with minimal concern for the internal details of the solver modules. Alternatively, this interface can be viewed as a way for solver developers to provide solution services to finite-element clients without having to embed finite-element abstractions within their solver libraries. The purpose of this document is to provide some level of documentation between the bare interface specification itself, which consists only of C/C++ header files, and the full documentation suite that supports the interface definition by providing considerable detail as to its design and implementation. This document primarily provides the ''how'' of calling the interface member functions, so that programmers can readily learn how to utilize the interface implementation without having to consider all the details contained in the interface's definition, design, and motivation. The interface specification is presented three times in this document, each time with an increasing level of detail. The first presentation provides a general overview of the calling sequence, in order to acquaint the programmer with a basic introduction to how the interface is used to ''train'' the underlying solver software on the particular finite-element problem …
Date: April 1, 1999
Creator: Williams, Alan B.; Otero, Ivan J.; Mish, Kyran D.; Tayor, Lee M. & Clay, Robert L.
System: The UNT Digital Library
Annual report to Congress, 1998 (open access)

Annual report to Congress, 1998

Section 205 of the Department of Energy Organization Act of 1977 established the Energy Information Administration (EIA). One of the mandates in this legislation is that EIA prepare for Congress an annual report summarizing both activities and information collected and published. EIA`s major 1998 accomplishments are profiled in the body of this edition of the Annual Report to Congress. Appendix A contains abstracts of significant reports issued by EIA in 1998 and a chart of all titles and a list of all feature articles published during the year. Appendix B contains graphs of selected performance measures. Appendix C lists contact information for EIA subject matter specialists. Appendix D lists the major laws which form the basis of EIA`s legislative mandate.
Date: April 1, 1999
Creator: unknown
System: The UNT Digital Library
Application of High Performance Computing for Automotive Design and Manufacturing (open access)

Application of High Performance Computing for Automotive Design and Manufacturing

This project developed new computer simulation tools which can be used in DOE internal combustion engine and weapons simulation programs currently being developed. Entirely new massively parallel computer modeling codes for chemically reactive and incompressible fluid mechanics with interactive physics sub-models were developed. Chemically reactive and aerodynamic flows are central parts in many DOE systems. Advanced computer modeling codes with new chemistry and physics capabilities can be used on massively parallel computers to handle more complex problems associated with chemically reactive propulsion systems, energy efficiency, enhanced performance and durability, multi-fuel capability and reduced pollutant emissions. The work for this project is also relevant to the design, development and application of advanced user-friendly computer codes for new high-performance computing platforms for manufacturing and which will also impact and interact with the U.S.'s advanced communications program. Finite element method (FEM) formulations were developed that are directly usable in simulating rapid deformation resulting from collision, impact, projectiles, etc. This simulation capability is applicable to both DOE (e.g., surety and penetration) and DoD (e.g., armor) applications. The models of plate and shell composite structures were developed for simulation of glass continuous strand mat and braided composite in thermoset polymer matrix. The developed numerical tools …
Date: April 1, 1999
Creator: Zacharia, T.
System: The UNT Digital Library
Application of nonlinear wave modulation spectroscopy to discern material damage (open access)

Application of nonlinear wave modulation spectroscopy to discern material damage

Materials containing structural damage have a far greater nonlinear elastic response than materials with no structural damage. This is the basis for nonlinear wave diagnostics of damage, methods which are remarkably sensitive to the detection and progression of damage in materials. Here the authors describe one nonlinear method, the application of harmonics and sum and difference frequency to discern damage in materials. The method is termed Nonlinear Wave Modulation Spectroscopy (NWMS). It consists of exciting a sample with continuous waves of two separate frequencies simultaneously, and inspecting the harmonics of the two waves, and their sum and difference frequencies (sidebands). Undamaged materials are essentially linear in their response to the two waves, while the same material, when damaged, becomes highly nonlinear, manifested by harmonics and sideband generation. The authors illustrate the method by experiments on uncracked and cracked plexiglass and sandstone samples, and by applying it to intact and damaged engine components.
Date: April 1999
Creator: Johnson, Paul A.; Sutin, Alexander & Van Den Abeele, Koen E.-A.
System: The UNT Digital Library
Application of the FETI Method to ASCI Problems: Scalability Results on One Thousand Processors and Discussion of Highly Heterogeneous Problems (open access)

Application of the FETI Method to ASCI Problems: Scalability Results on One Thousand Processors and Discussion of Highly Heterogeneous Problems

We report on the application of the one-level FETI method to the solution of a class of substructural problems associated with the Department of Energy's Accelerated Strategic Computing Initiative (ASCI). We focus on numerical and parallel scalability issues, and on preliminary performance results obtained on the ASCI Option Red supercomputer configured with as many as one thousand processors, for problems with as many as 5 million degrees of freedom.
Date: April 1, 1999
Creator: Bhardwaj, M.; Day, D.; Farhat, C.; Lesoinne, M; Pierson, K. & Rixen, D.
System: The UNT Digital Library
Aries-ST: Studies Report for the Period January 1, 1998 Through December 31, 1998 (open access)

Aries-ST: Studies Report for the Period January 1, 1998 Through December 31, 1998

During 1998, the General Atomics (GA) ARIES-Spherical Torus (ST) team examined several critical issues related to the physics performance of the ARIES-ST design, and a number of suggestions were made concerning possible improvements in performance. These included specification of a reference plasma equilibrium, optimization about the reference equilibrium to achieve higher beta limits, examination of three possible schemes for plasma initiation, development of a detailed scenario for ramp-up of the plasma current and pressure to its full, final operating values, an assessment of the requirement for electron confinement, and several suggestions for divertor heat flux reduction. The reference equilibrium was generated using the TOQ code, with the specification of a 100%, self-consistent bootstrap current. The equilibrium has {beta} = 51%, 10% below the stability limit (a margin specified by the ARIES-ST study). In addition, a series of intermediate equilibria were defined, corresponding to the ramp-up scenario discussed. A study of the influence of shaping on ARIES-ST performance indicates that significant improvement in both kink and ballooning stability can be obtained by modest changes in the squareness of the plasma. In test equilibria the ballooning beta limit is increased from 58% to 67%. Also the maximum allowable plasma-wall separation for kink …
Date: April 1, 1999
Creator: Chan, v. S.; Lao, L. L.; Lin-Liu, Y. R.; Miller, R. L.; Petrie, T. W.; Politzer, P. A. et al.
System: The UNT Digital Library
Attributes of a research environment that contribute to excellent research and development (open access)

Attributes of a research environment that contribute to excellent research and development

This paper presents initial work at two U. S. Department of Energy (DOE) national laboratories to identify attributes of DOE Laboratory research environments that are most important for fostering excellent research.
Date: April 1, 1999
Creator: Jordan, G. B.; Streit, L. D. & Binkley, J. S.
System: The UNT Digital Library
Audit report: Bechtel Jacobs payroll creation (open access)

Audit report: Bechtel Jacobs payroll creation

The Oak Ridge Operations Office (Operations Office) awarded a contract to the Bechtel Jacobs Company, LLC (Bechtel Jacobs) in December 1997. The terms of the contract require Bechtel Jacobs to create new jobs in the Oak Ridge area with a cumulative payroll of $427 million through Fiscal Year (FY) 2003. In FY 1998, the contract required Bechtel Jacobs to create $11 million in new payroll. The objective of the audit was to determine if Bechtel Jacobs met its commitment to create at least $11 million in new payroll in the Oak Ridge, Tennessee area through September 30, 1998. We could not determine if Bechtel Jacobs met its new payroll commitment. Bechtel Jacobs reported that it created $13.5 million in new payroll through September 30, 1998. In our opinion, the Department was not provided with sufficient data to fully verify that all claimed payroll had been created. The Operations Office verified that Bechtel National, Inc., and Jacobs Engineering Group Inc., created $4.9 million in new payroll through September 30, 1998. However, the only data supporting the remaining $8.6 million claimed by Bechtel Jacobs were letters from local companies showing the amount of new payroll claimed. The Operations Office did not require …
Date: April 1, 1999
Creator: Brendlinger, T.L.
System: The UNT Digital Library
An Audit Report on Catalog Operations at the Texas Parks and Wildlife Department (open access)

An Audit Report on Catalog Operations at the Texas Parks and Wildlife Department

Report of the Texas State Auditor's Office related to the correction of gross fiscal mismanagement by the catalog department of the Parks and Wildlife Department.
Date: April 1999
Creator: Texas. Office of the State Auditor.
System: The Portal to Texas History
Bayesian analysis of MEG visual evoked responses (open access)

Bayesian analysis of MEG visual evoked responses

The authors developed a method for analyzing neural electromagnetic data that allows probabilistic inferences to be drawn about regions of activation. The method involves the generation of a large number of possible solutions which both fir the data and prior expectations about the nature of probable solutions made explicit by a Bayesian formalism. In addition, they have introduced a model for the current distributions that produce MEG and (EEG) data that allows extended regions of activity, and can easily incorporate prior information such as anatomical constraints from MRI. To evaluate the feasibility and utility of the Bayesian approach with actual data, they analyzed MEG data from a visual evoked response experiment. They compared Bayesian analyses of MEG responses to visual stimuli in the left and right visual fields, in order to examine the sensitivity of the method to detect known features of human visual cortex organization. They also examined the changing pattern of cortical activation as a function of time.
Date: April 1, 1999
Creator: Schmidt, D. M.; George, J. S. & Wood, C. C.
System: The UNT Digital Library
Beam-Beam Collisions and Crossing Angles in RHIC (open access)

Beam-Beam Collisions and Crossing Angles in RHIC

This paper evaluates the strength of the head on a parasitic beam-beam collisions in RHIC when the crossing angle is 0.
Date: April 1, 1999
Creator: S., Peggs
System: The UNT Digital Library
Beam-target interactions in single-and multi-pulse radiography (open access)

Beam-target interactions in single-and multi-pulse radiography

This report describes calculations concerning the interaction of intense electron beam pulses with a solid target. In Section 2, we treat the propagation of a beam pulse through a dense plasma plume in front of the target, resulting from material blown off from the target by prior pulses. Because of the short magnetic decay-time, the primary effect of the plasma is to shift the focal spot of the beam longitudinally by an amount which is constant over most of the beam pulse. It may be possible to compensate for this effect by changing the upstream focusing elements from one beam pulse to the next. Section 3 describes a mechanism by which lighter ion species can diffuse to the surface of a plasma plume, thereby potentially increasing the concentration of bulk contaminant species such as hydrogen at the leading edge of the plume. These ions could then become a light-ion source for subsequent beam pulses. Based on the calculations, we tentatively recommend bulk contaminant fractions be limited to 10{sup -5}10{sup 4}. In Section 4, we estimate the number of adsorbed monolayers needed to provide a space-charge-limited (SCL) ion source at the target for the initial beam pulse. We find that {approx} …
Date: April 1, 1999
Creator: Chen, Y. J.; Hughes, T. P.; Oliver, B. V. & Welch, D. R.
System: The UNT Digital Library
BENCH-SCALE DEMONSTRATION OF HOT-GAS DESULFURIZATION TECHNOLOGY (open access)

BENCH-SCALE DEMONSTRATION OF HOT-GAS DESULFURIZATION TECHNOLOGY

The U.S. Department of Energy (DOE), Federal Energy Technology Center (FETC), is sponsoring research in advanced methods for controlling contaminants in hot coal gasifier gas (coal derived fuel-gas) streams of integrated gasification combined-cycle (IGCC) power systems. The hot gas cleanup work seeks to eliminate the need for expensive heat recovery equipment, reduce efficiency losses due to quenching, and minimize wastewater treatment costs. Hot-gas desulfurization research has focused on regenerable mixed-metal oxide sorbents that can reduce the sulfur in coal-derived fuel-gas to less than 20 ppmv and can be regenerated in a cyclic manner with air for multicycle operation. Zinc titanate (Zn{sub 2}, TiO{sub 4} or ZnTiO{sub 3}), formed by a solid-state reaction of zinc oxide (ZnO) and titanium dioxide (TiO{sub 2}), is currently one of the leading sorbents.
Date: April 1999
Creator: unknown
System: The UNT Digital Library