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Isotopic Cross Sections for Production of Gamma Rays Created by Neutron Interactions with {sup 11}B for E{sub n} Between 2 and 22 MeV: Tabulated Data

Description: Inelastic and nonelastic neutron interactions with {sup 11}B have been studied for incident neutron energies between 2 and 22 MeV. Neutrons from the Oak Ridge Electron Linear Accelerator (ORELA) impinged a sample of natural boron. Gamma rays resulting from neutron interactions were detected using a well-calibrated intrinsic-Ge detection system. Data reduction included compensation for Doppler broadening of the observed peaks and corrections due to incident neutron attenuation, effects due to multiple scattering of neutrons, and sample attenuation of the outgoing gamma rays. Cross sections for gamma rays having energies (in keV) of 2124, 4445, 4741, 5020, 6434, 6743+6793 (combined), and 7286 following inelastic scattering, of 478 keV from the {sup 11}B(n,n{alpha}{gamma}){sup 7}Li reaction, and of 718 keV from the {sup 11}B(n,2n{gamma}){sup 10}B reaction as functions of incident neutron energy are presented in tabular form.
Date: February 15, 2001
Creator: Larson, DC
Partner: UNT Libraries Government Documents Department

Small-Scale Ion Exchange Removal of Cesium and Technetium from Envelope B Hanford Tank 241-AZ-102

Description: The pretreatment process for the Hanford River Protection Project Waste Treatment Plant is to provide decontaminated Low-Activity Waste and concentrated elute streams for vitrification into low- and high-activity waste glass, respectively. The pretreatment includes sludge washing, filtration, precipitation, and ion exchange processes to remove entrained solids, strontium, transuranics, cesium, and technetium.
Date: February 15, 2001
Creator: King, W.D.
Partner: UNT Libraries Government Documents Department

Plutonium Immobilization Project - Cold Pour Phase 2 Test Results

Description: The U.S. Department of Energy will immobilize excess plutonium in the proposed Plutonium Immobilization Plant (PIP) at the Savannah River site (SRS) as part of a two-track approach for dispositioning weapons-usable plutonium. The Department of Energy is funding the development and testing effort for the PIP being conducted by Lawrence Livermore National Laboratory and Argonne National Laboratory. PIP is developing the ''Can-in Canister'' (CIC) technology that immobilizes plutonium by encapsulating it in ceramic forms (or pucks) and ultimately surrounding the forms with high-level waste glass to provide a deterrent to recovery. A cold (non-radioactive) test program was conducted to develop and verify the baseline design for the canister and internal hardware. Tests were conducted in two phases. Phase 1 Cold Pour Tests, conducted in 1999, were scoping tests. This paper describes the Phase 2 tests conducted in 2000 that verified the adequacy of the baseline and demonstrated compliance with repository requirements.
Date: February 15, 2001
Creator: Hamilton, L.
Partner: UNT Libraries Government Documents Department

Electron-gun-controlled thin film mirrors for remote sensing applications

Description: The ultimate limitation in obtainable resolution and sensitivity for space-based imaging systems is the size of the optical collecting aperture. Large collecting apertures are at odds with maintaining low launch costs and with current launch vehicle configurations. Development of a deployable mirror is one approach being considered to satisfy these conflicting requirements. The focus of this research is to develop fundamental technology toward the realization of deployable electron-gun-controlled piezoelectric thin films mirrors as shown below. A bimorph layer of film will bend in response to an applied electric field and can therefore be deformed into desirable shapes using a scanning electron gun. Surface curvature measurements govern the electron gun scanning strategy, yielding distributed shape corrections.
Date: February 15, 2000
Creator: HENSON,TAMMY D.; REDMOND,JAMES M.; WEHLBURG,JOSEPH C.; MARTIN,JEFFREY W. & MAIN,JOHN A.
Partner: UNT Libraries Government Documents Department

Rapid, automated gas chromatographic detection of organic compounds in ultra-pure water

Description: An automated gas chromatography was used to analyze water samples contaminated with trace (parts-per-billion) concentrations of organic analytes. A custom interface introduced the liquid sample to the chromatography. This was followed by rapid chromatographic analysis. Characteristics of the analysis include response times less than one minute and automated data processing. Analytes were chosen based on their known presence in the recycle water streams of semiconductor manufacturers and their potential to reduce process yield. These include acetone, isopropanol, butyl acetate, ethyl benzene, p-xylene, methyl ethyl ketone and 2-ethoxy ethyl acetate. Detection limits below 20 ppb were demonstrated for all analytes and quantitative analysis with limited speciation was shown for multianalyte mixtures. Results are discussed with respect to the potential for on-line liquid process monitoring by this method.
Date: February 15, 2000
Creator: MOWRY,CURTIS DALE; BLAIR,DIANNA S.; MORRISON,DENNIS J.; REBER,STEPHEN D. & RODACY,PHILIP J.
Partner: UNT Libraries Government Documents Department

Morphologies of uranium deposits produced during electrorefining of EBR-II spent nuclear fuel

Description: The morphologies of U metal samples from deposits produced by electrorefining of Experimental Breeder Reactor-II (EBR-II) spent fuel were examined using scanning electron microscopy, energy- and wavelength-dispersive X-ray spectroscopy, and metallography. The morphologies were analyzed to find correlations with the chemistry of the samples, the ER run conditions, and the deposit performance. A rough correlation was observed between morphology and Zr concentration; samples with Zr contents greater than approximately 200 ppm showed fine-grained, polycrystalline dendritic morphologies, while samples with Zr contents less than approximately 100 ppm were comprised of agglomerations or linked chains of rhomboidal single crystals. There were few correlations found between morphology, run conditions, and deposit performance.
Date: February 15, 2000
Creator: Totemeier, T. C.
Partner: UNT Libraries Government Documents Department

Project definition study for the National Biomedical Tracer Facility

Description: The University of Alabama at Birmingham (UAB) has conducted a study of the proposed National Biomedical Tracer Facility (NBTF). In collaboration with General Atomics, RUST International, Coleman Research Corporation (CRC), IsoMed, Ernst and Young and the advisory committees, they have examined the issues relevant to the NBTF in terms of facility design, operating philosophy, and a business plan. They have utilized resources within UAB, CRC and Chem-Nuclear to develop recommendations on environmental, safety and health issues. The Institute of Medicine Panel`s Report on Isotopes for Medicine and the Life Sciences took the results of prior workshops further in developing recommendations for the mission of the NBTF. The IOM panel recommends that the NBTF accelerator have the capacity to accelerate protons to 80 MeV and a minimum of 750 microamperes of current. The panel declined to recommend a cyclotron or a linac. They emphasized a clear focus on research and development for isotope production including target design, separation chemistry and generator development. The facility needs to emphasize education and training in its mission. The facility must focus on radionuclide production for the research and clinical communities. The formation of a public-private partnership resembling the TRIUMF-Nordion model was encouraged. An advisory panel should assist with the NBTF operations and prioritization.
Date: February 15, 1995
Creator: Roozen, K.
Partner: UNT Libraries Government Documents Department

Search for major genes with progeny test data to accelerate the development of genetically superior loblolly pine. Technical progress report

Description: This report details the progress of the three tasks of this project. The tasks are: (1) develop genetic models and analytical methods; (2) molecular confirmation of major gene segregation; and (3) develop strategies for marker-assisted breeding.
Date: February 15, 2000
Partner: UNT Libraries Government Documents Department

Laser Ultrasonic Furnace Tube Coke Monitor

Description: This reports summarizes the technical progress achieved during the third quarter of the ERIP project entitled, ''Laser Ultrasonic Furnace Tube Coke Monitor.'' The focus of work during this reporting period was the construction of an automated probe that will be used to measure the thickness of coke deposits in thermal cracking furnaces. A discovery was made during the last reporting period, which indicated that a conventional NDE broadband transducer could be used in conjunction with a sacrificial standoff composed of a fusible alloy to efficiently couple the transducer to a rough surface operating at high temperature. A probe was constructed that incorporates the recent discovery and initial testing of the probe is now underway. Because of other project commitments, the manpower available to allocate to the coke detector project was limited during the most recent quarter. As a result, the project is somewhat behind the original schedule. However, project expenditures are consistent with the project progress to date. The total program budget is $98,670 and the current project expenditures are approximately $24,000. The original contract budget period ends on April 30, 1999. We intend to request a six-month no-cost extension to the contract so that we may complete the project objectives.
Date: February 15, 1999
Partner: UNT Libraries Government Documents Department

Three-dimensional control of light in a two-dimensional photonic crystal slab

Description: A two-dimensional (2D) photonic crystal is an attractive alternative and complimentary to its 3D counterpart, due to fabrication simplicity. A 2D crystal, however, confines light only in the 2D plane, but not in the third direction, the z-direction. Earlier experiments show that such a 2D system can exist, providing that the boundary effect in z-direction is negligible and that light is collimated in the 2D plane. Nonetheless, the usefulness of such 2D crystals is limited because they are incapable of guiding light in z-direction, which leads to diffraction loss. This drawback presents a major obstacle for realizing low-loss 2D crystal waveguides, bends and thresholdless lasers. A recent theoretical calculation, though, suggests a novel way to eliminate such a loss with a 2D photonic crystal slab. The concept of a lightcone is introduced as a criterion for fully guiding and controlling light. Although the leaky modes of a crystal slab have been studied, there have until now no experimental reports on probing its guided modes and band gaps. In this paper, a waveguide-coupled 2D photonic crystal slab is successfully fabricated from a GaAs/Al{sub x}O{sub y} material system and its intrinsic transmission properties are studied. The crystal slab is shown to have a strong 2D band gap at {lambda} {approximately} 1.5 {micro}m. Light attenuates as much as {approximately}5dB per period in the gap, the strongest ever reported for any 2D photonic crystal in optical {lambda}. More importantly, for the first time, the crystal slab is shown to be capable of controlling light fully in all three-dimensions. The lightcone criterion is also experimentally confirmed.
Date: February 15, 2000
Creator: CHOW,KAI-CHEUNG; LIN,SHAWN-YU; JOHNSON,S.G.; VILLENEUVE,P.R.; JOANNOPOULOS,J.D.; WENDT,JOEL R. et al.
Partner: UNT Libraries Government Documents Department

Highly-Efficient Buried-Oxide-Waveguide Laser by selective Oxidation

Description: An edge-emitting buried-oxide waveguide (BOW) laser structure employing lateral selective oxidation of AlGaAs layers above and below the active region for waveguiding and current confinement is presented. This laser configuration has the potential for very small lateral optical mode size and high current confinement and is well suited for integrated optics applications where threshold current and overall efficiency are paramount. Optimization of the waveguide design, oxide layer placement, and bi-parabolic grading of the heterointerfaces on both sides of the AlGaAs oxidation layers has yielded 95% external differential quantum efficiency and 40% wall-plug efficiency from a laser that is very simple to fabricate and does not require epitaxial regrowth of any kind.
Date: February 15, 2000
Creator: VAWTER,GREGORY A.; SPAHN,OLGA B.; ALLERMAN,ANDREW A. & GAO,YING
Partner: UNT Libraries Government Documents Department

Utilizing benchmark data from the ANL-ZPR diagnostic cores program

Description: The support of the criticality safety community is allowing the production of benchmark descriptions of several assemblies from the ZPR Diagnostic Cores Program. The assemblies have high sensitivities to nuclear data for a few isotopes. This can highlight limitations in nuclear data for selected nuclides or in standard methods used to treat these data. The present work extends the use of the simplified model of the U9 benchmark assembly beyond the validation of k{sub eff}. Further simplifications have been made to produce a data testing benchmark in the style of the standard CSEWG benchmark specifications. Calculations for this data testing benchmark are compared to results obtained with more detailed models and methods to determine their biases. These biases or corrections factors can then be applied in the use of the less refined methods and models. Data testing results using Versions IV, V, and VI of the ENDF/B nuclear data are presented for k{sub eff}, f{sup 28}/f{sup 25}, c{sup 28}/f{sup 25}, and {beta}{sub eff}. These limited results demonstrate the importance of studying other integral parameters in addition to k{sub eff} in trying to improve nuclear data and methods and the importance of accounting for methods and/or modeling biases when using data testing results to infer the quality of the nuclear data files.
Date: February 15, 2000
Creator: Schaefer, R. W. & McKnight, R. D.
Partner: UNT Libraries Government Documents Department

Petroleum supply monthly, January 1996

Description: The Petroleum Supply Monthly (PSM) is one of a family of four publications produced by the Petroleum Supply Division within the Energy Information Administration (EIA) reflecting different levels of data timeliness and completeness. The other publications are the Weekly Petroleum Status Report (WPSR), the Winter Fuels Report, and the Petroleum Supply Annual (PSA). Data presented in the PSM describe the supply and disposition of petroleum products in the United States and major US geographic regions. The data series describe production, imports and exports, inter-Petroleum Administration for Defense (PAD) District movements, and inventories by the primary suppliers of petroleum products in the United States (50 States and the District of Columbia). The reporting universe includes those petroleum sectors in primary supply. Included are: petroleum refiners, motor gasoline blenders, operators of natural gas processing plants and fractionators, inter-PAD transporters, importers, and major inventory holders of petroleum products and crude oil. When aggregated, the data reported by these sectors approximately represent the consumption of petroleum products in the United States. Data presented in the PSM are divided into two sections: Summary Statistics and Detailed Statistics.
Date: February 15, 1996
Partner: UNT Libraries Government Documents Department

Operating and assurance plan. Revision 5

Description: This document discusses the organization, process management, and performance assessment and improvement of Lawrence Berkeley Laboratory. Topics discussed include: policy; planning; organizational structure; staff proficiency; communication processes; hazards and risks in the work process; process control; documents and records management; self assessments and corrective actions.
Date: February 15, 1996
Partner: UNT Libraries Government Documents Department

Waste characterization for radioactive liquid waste evaporators at Argonne National Laboratory - West.

Description: Several facilities at Argonne National Laboratory - West (ANL-W) generate many thousand gallons of radioactive liquid waste per year. These waste streams are sent to the AFL-W Radioactive Liquid Waste Treatment Facility (RLWTF) where they are processed through hot air evaporators. These evaporators remove the liquid portion of the waste and leave a relatively small volume of solids in a shielded container. The ANL-W sampling, characterization and tracking programs ensure that these solids ultimately meet the disposal requirements of a low-level radioactive waste landfill. One set of evaporators will process an average 25,000 gallons of radioactive liquid waste, provide shielding, and reduce it to a volume of six cubic meters (container volume) for disposal. Waste characterization of the shielded evaporators poses some challenges. The process of evaporating the liquid and reducing the volume of waste increases the concentrations of RCIU regulated metals and radionuclides in the final waste form. Also, once the liquid waste has been processed through the evaporators it is not possible to obtain sample material for characterization. The process for tracking and assessing the final radioactive waste concentrations is described in this paper, The structural components of the evaporator are an approved and integral part of the final waste stream and they are included in the final waste characterization.
Date: February 15, 1999
Creator: Christensen, B. D.
Partner: UNT Libraries Government Documents Department

Large eddy simulation and its implementation in the COMMIX code.

Description: Large eddy simulation (LES) is a numerical simulation method for turbulent flows and is derived by spatial averaging of the Navier-Stokes equations. In contrast with the Reynolds-averaged Navier-Stokes equations (RANS) method, LES is capable of calculating transient turbulent flows with greater accuracy. Application of LES to differing flows has given very encouraging results, as reported in the literature. In recent years, a dynamic LES model that presented even better results was proposed and applied to several flows. This report reviews the LES method and its implementation in the COMMIX code, which was developed at Argonne National Laboratory. As an example of the application of LES, the flow around a square prism is simulated, and some numerical results are presented. These results include a three-dimensional simulation that uses a code developed by one of the authors at the University of Notre Dame, and a two-dimensional simulation that uses the COMMIX code. The numerical results are compared with experimental data from the literature and are found to be in very good agreement.
Date: February 15, 1999
Creator: Sun, J. & Yu, D.-H.
Partner: UNT Libraries Government Documents Department

Ball lens reflections by direct solution of Maxwell`s equations

Description: Ball lenses are important for many applications. For example, ball lenses can be used to match the mode of a laser diode (LD) to a single mode fiber (SMF), essential for low-loss, high bit rate communication systems. Modeling the propagation of LD light through a ball lens presents a challenge due to the large angular divergence of the LD field (typically > 20{degrees} HWHM) and the subsequent significant effect of spherical aberration. Accurately calculating the reflected power is also difficult, but essential, since reflections as small as {minus}30 dB can destabilize the LID. A full-wave analysis of this system using, e.g., a finite-difference time-domain method is not practical because of the size of the ball lens, typically hundreds of wavelengths in diameter. Approximate scalar methods can give good results in some cases, but fail to calculate reflected power and miss polarization effects entirely. The authors` approach exploits the fact that the scattering of an arbitrary electromagnetic beam from a sphere is an exactly solvable problem. The scattering of a plane wave from a sphere is a classical problem which was solved by Mie in 1908. More recently, various workers have considered the scattering of a Gaussian beam from a sphere and its numerical implementation for other applications. To the authors knowledge, this is the first time this approach has been applied to a problem in optical design. They are able to calculate reflection and transmission accurately with modest computational effort.
Date: February 15, 1995
Creator: Ratowsky, R.P.; Deri, R.J. & Kallman, J.S.
Partner: UNT Libraries Government Documents Department

Preparation of bismuth powder

Description: The Purpose of this manual is to describe preparation of bismuth powder for use in process operations. Bismuth powder is to be prepared in Room 232 of ``T`` Building where all necessary apparatus is installed.
Date: February 15, 1949
Creator: Cox, G.C.
Partner: UNT Libraries Government Documents Department

Cooperative research in coal liquefaction. Final report, May 1, 1990-- April 30, 1991

Description: The Consortium for Fossil Fuel Liquefaction Science (CFFLS) is currently engaged in a three year contract with the US Department of Energy investigating a range of research topics dealing with direct coal liquefaction. This report summarizes the results of this program in its second year, from May 1, 1990 to April 30, 1991. Accomplishments for this period are presented for the following tasks: Iron-based catalysts for coal liquefaction, exploratory research on coal conversion, novel coal liquefaction concepts, and novel catalysts for coal liquefaction.
Date: February 15, 1992
Creator: Huffman, G.P.
Partner: UNT Libraries Government Documents Department

Magnetic correlations in doped transition metal oxides

Description: The authors review recent reactor- and spallation-source-based neutron scattering experiments on the magnetic fluctuations and order in a variety of doped transition metal oxides. In particular, data are shown for the NiO chain compound, Y{sub 2{minus}x}Ca{sub x}BaNiO{sub 5}, the two-dimensional cuprate superconductors La{sub 2{minus}x}Sr{sub x}CuO{sub 4} and YBa{sub 2}Cu{sub 3} O{sub 6+x}, and the classical three-dimensional ``Mott-Hubbard`` system V{sub 2{minus}y}O{sub 3}.
Date: February 15, 1995
Creator: Aeppli, G.; Bao, W. & Broholm, C.
Partner: UNT Libraries Government Documents Department

Phonon density of states in Fe/Cr (001) superlattices and Tb-Fe thin-film alloys.

Description: Inelastic nuclear scattering of X-rays from the 14.413 keV nuclear resonance of {sup 57}Fe was employed to measure directly the Fe-projected phonon density of states (DOS) in MBE-grown Fe/Cr(00l) superlattices on MgO(001). The Moessbauer-inactive {sup 56}Fe isotope was used in the Fe layers. A 1{angstrom} thick Moessbauer-active {sup 57}Fe-probe layer (95% enriched) was placed at different locations within the Fe layers. This procedure permits one to distinguish phonon density of states at the Fe-Cr-interface from that at the center of the Fe-film. Distinct differences have been observed in the DOS of our samples. The phonon DOS of an amorphous Tb{sub 33}Fe{sub 67} alloy film was found to be a broad and structureless hump, contrary to that of an epitaxial TbFe{sub 2} film, which exhibits characteristic features.
Date: February 15, 1999
Creator: Alp, E. E.; Keune, W.; Roehlsberger, R.; Ruckert, T.; Schror, H. & Sturhahn, W.
Partner: UNT Libraries Government Documents Department