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Bench-scale co-processing

Description: The objective of this contract is to extend and optimize UOP's single-stage slurry-catalyzed co-processing scheme. Particular emphasis is given to defining and improving Mo catalyst utilization and cost, evaluating alternative and disposable slurry-catalyst systems, and improving catalyst recycle and recovery techniques. During the previous quarter, a catalyst concentration study was completed. The study showed that the highest nondistillable conversions and liquid yields were achieved using liquid recycle at temperatures in the range of 450--460{degree}C. At these high severity conditions, the liquid product yield and light ends yield were nearly independent of catalyst concentration. During the current quarter a follow-up study was conducted without catalyst. The objective of this study was to determine whether the improved high temperature operability was due to improved hydrodynamics resulting from the use of liquid recycle or whether catalyst, also plays a role, even at small concentrations. The results of bench-scale Run 28 are discussed in this report. 1 ref., 12 figs.
Date: July 9, 1990
Creator: Nafis, D.A.; Gatsis, J.G.; Lea, C. & Miller, M.A.
Partner: UNT Libraries Government Documents Department

Bench-scale co-processing

Description: The objective of this current is to extend and optimize UOP's single-stage slurry-catalyzed co-processing scheme, which has developed under previous Contract AC22-84PC70002. Particular emphasis is given to defining and improving catalyst utilization and costs, evaluating alternative and disposable slurry-catalyst systems, and improving catalyst recycle and recovery techniques. The work during this quarter involved a series of bench-scale runs using a new Mo-based slurry catalyst. The results of bench-scale Runs 24 and 25 are discussed in the following report. 7 refs., 4 figs., 3 tabs.
Date: March 7, 1990
Creator: Nafis, D.A.; Gatsis, J.G.; Lea, C. & Miller, M.A.
Partner: UNT Libraries Government Documents Department

Effects of low-level radiation upon the hematopoietic steam cell: implications for leukemogenesis

Description: These studies have addressed firstly the effect of single small doses of x-ray upon murine hematopoietic stem cells to obtain a better estimate of the D/sub q/. It is small, of the order of 20 rads. Secondly, a dose fractionation schedule tht does not kill or perturb the kinetics of hemopoietic cell proliferation was sought in order to investigate the leukemogenic potential of low level radiation upon an unperturbed hemopoietic system. The studies reported herein show tht 1.25 rads every other day decrease the CFU-S content of bone marrow by the time 40 rads are accumulated. Studies on the effect of 0.5, 1.0, 2.0, and 3.0 rads 3 times per week are under way. Two rads 3 times per week produced a modest decrease in CFU-S content of bone marrow after an accumulation of 68 rads. With 3.0 rads 3 times per week an accumulation of 102 rads produces a significant decrease in CFU-S content of bone marrow. Dose fractionation at 0.5 and 1.0 rad 3 times per week has not produced a CFU-S depression after accumulation of 17 and 34 rads. Radiation leukemogenesis studies published to date have utilized single doses and chronic exposure schedules that probably have significantly perturbed the kinetics of hematopoietic stem cells. Whether radiation will produce leukemia in animal models with dose schedules that do not perturb kinetics of hematopoietic stem cells remains to be seen.
Date: January 1, 1983
Creator: Cronkite, E.P.; Bond, V.P.; Carsten, A.L.; Miller, M.E. & Bullis, J.E.
Partner: UNT Libraries Government Documents Department

Microstructural characterization of irradiated Fe-Cu-Ni-P model steels

Description: The microstructure of Fe-Cu-Ni-P model pressure vessel steels after neutron irradiation and thermal aging has been characterized by atom probe field-ion microscopy and augmented by transmission electron microscopy. High densities of small, roughly spherical or disc shaped copper clusters/precipitates were observed in the neutron irradiated alloys that contained copper. Small spherical phosphorus clusters were observed in the irradiated copper-free alloys, and copper phosphides were observed in a high phosphorus Fe-Cu-Ni-P alloy. None of these clusters/precipitates were observed in the thermally aged materials. The increases in the tensile and yield strengths that were observed after neutron irradiation resulted from these clusters and other lattice defects. 14 refs., 8 figs., 2 tabs.
Date: January 1, 1987
Creator: Miller, M.K.; Hoelzer, D.T.; Ebrahimi, F.; Hawthorne, J.R. & Burke, M.G.
Partner: UNT Libraries Government Documents Department

Estimating calibration equations for predicting Ra-226 soil concentrations using RTRAK in-situ detectors at the Ambrosia Lake, New Mexico, Umtra site

Description: This report describes a field study conducted at the Ambrosia Lake, New Mexico, UMTRA site to obtain data for calibrating the RTRAK Sodium Iodide (NaI) detectors for estimating concentrations of Ra-226 in surface soil. The statistical analyses indicate that the data are useful for estimating the calibration equations. Several statistical models are used to evaluate which model is best as a basis for the calibration equations. A procedure is provided for using the estimated calibration equations and extensive RTRAK measurements to estimate the average Ra-226 concentration on 100-m/sup 2/ land areas to determine whether additional remedial action is needed. The UMTRA Project office proposes to use the RTRAK for cleanup verification of surface Ra-226 contamination. The system enables 100% coverage of areas having undergone remedial action. The sensitivity of the system enables verification at less than 5 pCi/g averaged over 100 m/sup 2/, as specified by the Environmental Protection Agency (EPA) standards (40 CFR Part 192). This analysis demonstrates RTRAK's ability to meet reasonable standards of statistical accuracy, using commonly accepted procedures. 5 refs., 8 figs., 1 tab.
Date: June 1, 1988
Creator: Gilbert, R. O.; Meyer, H. R.; Miller, M. L. & Begley, C.
Partner: UNT Libraries Government Documents Department

The role of actinide burning and the Integral Fast Reactor in the future of nuclear power

Description: A preliminary assessment is made of the potential role of actinide burning and the Integral Fast Reactor (IFR) in the future of nuclear power. The development of a usable actinide burning strategy could be an important factor in the acceptance and implementation of a next generation of nuclear power. First, the need for nuclear generating capacity is established through the analysis of energy and electricity demand forecasting models which cover the spectrum of bias from anti-nuclear to pro-nuclear. The analyses take into account the issues of global warming and the potential for technological advances in energy efficiency. We conclude, as do many others, that there will almost certainly be a need for substantial nuclear power capacity in the 2000--2030 time frame. We point out also that any reprocessing scheme will open up proliferation-related questions which can only be assessed in very specific contexts. The focus of this report is on the fuel cycle impacts of actinide burning. Scenarios are developed for the deployment of future nuclear generating capacity which exploit the advantages of actinide partitioning and actinide burning. Three alternative reactor designs are utilized in these future scenarios: The Light Water Reactor (LWR); the Modular Gas-Cooled Reactor (MGR); and the Integral Fast Reactor (FR). Each of these alternative reactor designs is described in some detail, with specific emphasis on their spent fuel streams and the back-end of the nuclear fuel cycle. Four separation and partitioning processes are utilized in building the future nuclear power scenarios: Thermal reactor spent fuel preprocessing to reduce the ceramic oxide spent fuel to metallic form, the conventional PUREX process, the TRUEX process, and pyrometallurgical reprocessing.
Date: December 1, 1990
Creator: Hollaway, W. R.; Lidsky, L. M. & Miller, M. M.
Partner: UNT Libraries Government Documents Department

Sampling errors associated with soil composites used to estimate mean Ra-226 concentrations at an UMTRA remedial-action site

Description: The decision whether to take additional remedial action (removal of soil) from regions contaminated by uranium mill tailings involves collecting 20 plugs of soil from each 10-m by 10-m plot in the region and analyzing a 500-g portion of the mixed soil for /sup 226/Ra. A soil sampling study was conducted in the windblown mill-tailings flood plain area at Shiprock, New Mexico, to evaluate whether reducing the number of soil plugs to 9 would have any appreciable impact on remedial-action decisions. The results of the Shiprock study are described and used in this paper to develop a simple model of the standard deviation of /sup 226/Ra measurements on composite samples formed from 21 or fewer plugs. This model is used to predict as a function of the number of soil plugs per composite, the percent accuracy with which the mean /sup 226/Ra concentration in surface soil can be estimated, and the probability of making incorrect remedial action decisions on the basis of statistical tests. 8 refs., 15 figs., 9 tabs.
Date: July 1, 1987
Creator: Gilbert, R.O.; Baker, K.R.; Nelson, R.A.; Miller, R.H. & Miller, M.L.
Partner: UNT Libraries Government Documents Department

Reservoir engineering studies of the Gladys McCall geopressured-geothermal resource. Final report

Description: Transient pressure analysis techniques have been used to evaluate the performance of the Gladys McCall geopressured-geothermal reservoir. A fault-controlled aquifer influx model has also been developed to account for pressure support observed during both reservoir depletion and recovery phases. The Gladys McCall No. 1 well was drilled and completed in the lower Miocene geopressured sandstones under the US Department of energy geopressured-geothermal research program. The well was shut in october 1987 after producing over 27 MMstb of brine and 676 MMscf gas since October 1983. Eight pressure transient tests were conducted in the well. Analysis of transient pressure data provided a quantitative evaluation of reservoir characteristics, including: (a) formation transmissibility and skin, (b) the size and possible shape of the main producing reservoir, (c) characteristics of the pressure support mechanism. The pressure behavior of 1983 Reservoir Limits Test (RLT) suggested that the Gladys McCall reservoir might have a long narrow shape with the well located off-center. An elongated numerical model developed accordingly was able to reproduce the pressure characteristics show in the test. During both the reservoir production and shut-in periods, pressure buildup tests indicated some degree of external pressure support. Aquifer recharging was believed to be the main source. Based on reservoir material-balance calculations, an aquifer influx model was derived from a conceptual model of water leakage through a partially sealing fault into the reservoir under steady-state conditions. Moreover, a match of the pressure history required that the conductivity of the fault be a function of the pressure difference between the supporting aquifer and the reservoir.
Date: September 1, 1993
Creator: Lea, C. M.; Lee, K. & Miller, M. A.
Partner: UNT Libraries Government Documents Department

Electrofishing survey of the Great Miami River, September 1992. Annual report

Description: At the end of summer in 1992 the fishery of the Great Miami River took an unexpected deviation from the stasis of past years as an intense suspended algal bloom decreased the compositional diversity found at the lower GMR stations. Daytime supersaturation of oxygen and elevated pHs, reaching 9 by midday during the month of August, undoubtedly caused severe deficits of oxygen at night. Despite the aeration at every riffle, the intensities of the biological processes in the water were sufficient to cause very high positive and negative excursions of oxygen over the day and night cycle. This report documents a fish harvest that was conducted as part of the oxygen excess/deficit study.
Date: March 1, 1993
Creator: Miller, M. C.; Bixby, R.; Engman, J.; Ross, L. & Stocker, L.
Partner: UNT Libraries Government Documents Department

Atom probe field ion microscopy of Type 308 CRE stainless steel welds

Description: Addition of controlled residual elements (CRE), such as 0.007 wt % B, to type 308 stainless steel welds, improved creep-rupture properties. In this paper, B distribution and microstructure development were studied. The microstructural evolution during high-temperature aging was found to similar to that of commercial SS308 welds. Atom probe analysis showed that B and C segregate to the ferrite-austenite interface. Thermodynamic calculations suggest that the segregation is due to preferential partitioning of B and C to the liquid during solidification. Further work is needed to study B redistribution in aging stages.
Date: December 31, 1995
Creator: Babu, S. S.; David, S. A.; Vitek, J. M. & Miller, M. K.
Partner: UNT Libraries Government Documents Department

Mechanisms of gas bubble retention

Description: Retention and episodic release of flammable gases are critical safety concerns regarding double-shell tanks (DSTs) containing waste slurries. Previous investigations have concluded that gas bubbles are retained by the slurry that has settled at the bottom of the DST. However, the mechanisms responsible for the retention of these bubbles are not well understood. In addition, the presence of retained gas bubbles is expected to affect the physical properties of the sludge, but essentially no literature data are available to assess the effect of these bubbles. The rheological behavior of the waste, particularly of the settled sludge, is critical to characterizing the tendency of the waste to retain gas bubbles. The objectives of this study are to elucidate the mechanisms contributing to gas bubble retention and release from sludge such as is in Tank 241-SY-101, understand how the bubbles affect the physical properties of the sludge, develop correlations of these physical properties to include in computer models, and collect experimental data on the physical properties of simulated sludges with bubbles. This report presents a theory and experimental observations of bubble retention in simulated sludge and gives correlations and new data on the effect of gas bubbles on sludge yield strength.
Date: September 1, 1994
Creator: Gauglitz, P. A.; Mahoney, L. A.; Mendoza, D. P. & Miller, M. C.
Partner: UNT Libraries Government Documents Department

Atom probe field ion microscopy and related topics: A bibliography 1992

Description: This bibliography contains citations of books, conference proceedings, journals, and patents published in 1992 on the following types of microscopy: atom probe field ion microscopy (108 items); field emission microscopy (101 items); and field ion microscopy (48 items). An addendum of 34 items missed in previous bibliographies is included.
Date: December 1, 1993
Creator: Russell, K. F.; Godfrey, R. D. & Miller, M. K.
Partner: UNT Libraries Government Documents Department

Design and fabrication of the uranium drum standards

Description: The segmented gamma scanner has become an important instrument for assaying the special nuclear material content of low-density scrap and waste in 55-gal. drums. To perform these assays accurately, we need appropriate standards to calibrate the response of the system including the detector efficiency, the absorber in front of the detector, and the collimator geometry. A set of three uranium drum standards has been fabricated at Los Alamos. This paper discusses a Monte Carlo calculation to optimize the design of the drums. The drum standards are prepared using 20 modular 4-{ell} bottles in each drum. This paper also describes the fabrication procedure, which includes weighing the uranium oxide and the chemical analyzing of the uranium concentration. Also presented is the vertical scanning data of the 4- {ell} bottles to assure uniform mixing of the uranium and the diluent. Finally, the nondestructive measurements for checking consistency among the three drum standards am discussed.
Date: August 1, 1993
Creator: Hsue, F.; Long, S. M.; Hsue, S. T. & Miller, M. C.
Partner: UNT Libraries Government Documents Department

Safeguards instrumentation for continuous unattended monitoring in plutonium fuel fabrication plants

Description: Nondestructive assay (NDA) systems have been developed for use in an automated mixed oxide fabrication facility. Unique features have been developed for the NDA systems to accommodate robotic sample handling and remote operation. In addition, the systems have been designed to obtain International Atomic Energy Agency inspection data without the need for an inspector at the facility at the time of the measurements. The equipment is being designed to operate continuously in an unattended mode with data storage for periods of up to one month. The design, performance characteristics, and authentication of the NDA systems are described. The data related to reliability, precision, and accuracy are presented.
Date: June 1, 1993
Creator: Menlove, H. O.; Miller, M. C.; Ohtani, T.; Seya, M. & Takahashi, S.
Partner: UNT Libraries Government Documents Department

Electrostatic reduction of particulates for laser resistant hafnia coatings

Description: The authors have reduced by 50% particulate defect density of hafnia coatings deposited onto silicon substrates through the use of electric fields, physical barriers and deposition rate. In an effort to reduce the number of hafnia (HfO{sub 2}) particulates deposited onto silicon wafers, parallel plate electrodes were placed on either side of the evaporant plume. The particulate level was determined as the deposition rate was varied from 0.75 {angstrom}/sec to 12 {angstrom}/sec. Then, parallel plate electrodes were placed on either side of the plume as a way of electrostatically deflecting hafnia particulates away from the substrates. Later a single plate electrode was used in conjunction with a physical barrier placed over the hearth. The results of the study indicate that minimal defects occur when a parallel plate electric field is applied in conjunction with a fast deposition rate. Using a screen as a physical barrier, and/or a single electrode had little or no effect. This data may be useful in the manufacture of multilayer optical coatings with high laser damage thresholds.
Date: December 1, 1993
Creator: Miller, M. D.; Chow, R. & Loomis, G. E.
Partner: UNT Libraries Government Documents Department

Blue and Green Light? Wavelength Scaling for NIF

Description: Use of the National Ignition Facility to also output frequency-doubled (.53{micro}m) laser light would allow significantly more energy to be delivered to targets as well as significantly greater bandwidth for beam smoothing. This green light option could provide access to new ICF target designs and a wider range of plasma conditions for other applications. The wavelength scaling of the interaction physics is a key issue in assessing this green light option. Wavelength scaling theory based on the collisionless plasma approximation is explored, and some limitations associated with plasma collisionality are examined. Important features of the wavelength scaling are tested using the current data base, which is growing. It appears that, with modest restrictions, .53{micro}m light couples with targets as well as .35{micro}m light does. A more quantitative understanding of the beneficial effects of SSD on the interaction physics is needed for both .53{micro}m and .35{micro}m light.
Date: August 21, 2003
Creator: Suter, L; Miller, M; Moody, J & Kruer, W
Partner: UNT Libraries Government Documents Department

LSST data pipeline prototyping plans and strategy

Description: In this document we describe our approach and strategy for building the prototype for the image-stream analysis data pipeline. We start by describing the main research areas upon which we will be focusing; we then describe our plans on how to carry these research ideas to implement the data pipeline.
Date: May 27, 2004
Creator: Abdulla, G M; Brase, J; Cook, K & Miller, M
Partner: UNT Libraries Government Documents Department

Role of Smarter Grids in Variable Renewable Resource Integration

Description: This presentation discusses the role of smarter grids in variable renewable resource integration and references material from a forthcoming ISGAN issue paper: Smart Grid Contributions to Variable Renewable Resource Integration, co-written by the presenter and currently in review.
Date: July 1, 2012
Creator: Miller, M.
Partner: UNT Libraries Government Documents Department

Area 5 Site Characterization Project: Report of hydraulic property analysis through August 1993

Description: The Area 5 Site Characterization Project is designed to determine the suitability of the Radioactive Waste Management Site (RWMS) for disposal of low-level waste (LLW), mixed waste (MW) and transuranic waste (TRU). The Desert Research Institute (DRI) has supported the Area 5 Site Characterization Project for the US Department of Energy, Nevada Operations Office (DOE/NV), Environmental Restoration and Waste Management Division (ERWM), Waste Operations Branch (WOB). The purpose of DRI`s Area 5 Site Characterization project is to characterize important properties of the upper vadose zone which influence infiltration and redistribution of water and transport of solutes as well as to characterize the water quality and hydrologic conditions of the uppermost aquifer. This report describes methods and presents a summary of all data and results from laboratory physical and chemical testing from Pilot Wells and Science Trench borehole samples through August 1993. DRI laboratories performed soil water content, soil water potential, soil bulk density, soil water extract isotope analyses and soil water chemistry analyses.
Date: December 1, 1993
Creator: Estrella, R.; Tyler, S.; Chapman, J. & Miller, M.
Partner: UNT Libraries Government Documents Department

Area 5 Site characterization project report, FY 1994

Description: The Area 5 Site Characterization Project is designed to determine the suitability of the Radioactive Waste Management Site (RWMS) for disposal of low-level waste (LLW), mixed waste (MW) and transuranic waste (TRU). The Desert Research institute (DRI) has conducted this study for the Area 5 Site Characterization Project for the US Department of Energy, Nevada Operations Office (DOE/NV), Waste Management Division (WMD). The purpose of DRI`s Area 5 Site Characterization Project is to characterize important properties of the upper vadose zone which influence infiltration and redistribution of water and transport of solutes as well as to characterize the water quality and hydrologic conditions of the uppermost aquifer. This report describes methods and presents a summary of all data and results from laboratory physical and chemical testing from borehole samples through September 1994. DRI laboratories performed soil water content, soil water potential, soil bulk density, and soil water extract isotope analyses.
Date: September 1, 1994
Creator: Albright, W.; Tyler, S.; Chapman, J.; Miller, M. & Estrella, R.
Partner: UNT Libraries Government Documents Department

Considerations for How to Rate CPV

Description: The concentrator photovoltaic (CPV) industry is introducing multiple products into the marketplace, but, as yet, the; community has not embraced a unified method for assessing a nameplate rating. The choices of whether to use 850,; 900, or 1000 W/m2 for the direct-normal irradiance and whether to link the rating to ambient or cell temperature will; affect how CPV modules are rated and compared with other technologies. This paper explores the qualitative and; quantitative ramifications of these choices using data from two multi-junction CPV modules and two flat-plate; modules.
Date: February 1, 2011
Creator: Kurtz, S.; Miller, M.; Marion, B.; Emery, K.; McConnell, R.; Surendran, S. et al.
Partner: UNT Libraries Government Documents Department

Smart Libraries: Best SQE Practices for Libraries with an Emphasis on Scientific Computing

Description: As scientific computing applications grow in complexity, more and more functionality is being packaged in independently developed libraries. Worse, as the computing environments in which these applications run grow in complexity, it gets easier to make mistakes in building, installing and using libraries as well as the applications that depend on them. Unfortunately, SQA standards so far developed focus primarily on applications, not libraries. We show that SQA standards for libraries differ from applications in many respects. We introduce and describe a variety of practices aimed at minimizing the likelihood of making mistakes in using libraries and at maximizing users' ability to diagnose and correct them when they occur. We introduce the term Smart Library to refer to a library that is developed with these basic principles in mind. We draw upon specific examples from existing products we believe incorporate smart features: MPI, a parallel message passing library, and HDF5 and SAF, both of which are parallel I/O libraries supporting scientific computing applications. We conclude with a narrative of some real-world experiences in using smart libraries with Ale3d, VisIt and SAF.
Date: December 15, 2004
Creator: Miller, M C; Reus, J F; Matzke, R P; Koziol, Q A & Cheng, A P
Partner: UNT Libraries Government Documents Department

Micropixe as a tool to search for uranium-bearing particles in lung tissues

Description: A proton microbeam is proposed as a tool to search for uranium-bearing particles in lung tissues. Preliminary experiments have been undertaken by irradiating with protons lung tissues of dogs previously exposed to uranium ore. 7 references.
Date: January 1, 1982
Creator: Paschoa, A.S.; Wrenn, S.C.; Miller, M.E.; Jones, K.W.; Cholewa, M. & Hanson, A.L.
Partner: UNT Libraries Government Documents Department

Atom Probe Field Ion Microscopy of Zr-Doped Polysynthetically Twinned Titanium Aluminide

Description: Interracial segregation and partitioning in a polysynthetically twinned Ti-48.4 at.% Al-0.6% Zr alloy were investigated by atom probe field ion microscopy and atom probe tomography. The compositions of the {gamma} and {alpha}{sub 2} phases were determined to be Ti-47.5% Al-O.71% Zr-0.06% O and Ti-31.6% Al-0.68% Zr-2.4% O, respectively. These results indicate a high concentration of zirconium in both matrix phases, confirming a strength increase through solid-solution strengthening, but no significant zirconium partitioning to either phase. Although zirconium additions produced a refined lamellar microstructure in this material, compositional analysis of {gamma}/{gamma} and {gamma}/{alpha}{sub 2} interfaces showed no evidence of significant zirconium segregation. This suggests that zirconium additions may produce a refined lamellar microstructure, but may not be effective at providing resistance to growth and coarsening.
Date: February 28, 1999
Creator: Inui, H.; Larson, D.J.; Miller, M.K. & Yamaguchi, M.
Partner: UNT Libraries Government Documents Department