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An Approach for the Analysis of Regulatory Analytes in High Level Radioactive Waste Stored at Hanford, Richland, Washington

Description: Radiation levels, salt concentration, and the oxidizing nature of the waste dictates modifications to the SW-846 methods. Modified methods will be used to meet target EQLs and QC currently in SW-846. Method modifications will be validated per SW-846 and HASQARD and will be documented consistent with WAC 173-303-910. The affect of modifications to holding times and storage conditions will be evaluated using techniques developed by Maskarinec and Bayne (1996). After validating the methods and performing the holding time study on a minimum of two Phase 1 candidate feed source tank wastes, DOE and Ecology will assess: whether different methods are needed, whether holding time/storage conditions should be altered, whether the high priority analyte list should be refined, and which additional tank waste needs to be characterized.
Date: January 4, 1999
Creator: Wiemers, K. D.; Miller, M. & Lerchen, M. E.
Partner: UNT Libraries Government Documents Department

Bench-scale co-processing. Quarterly report No. 5, April 1, 1989--June 30, 1989

Description: This quarterly report is the fifth for Contract DE-AC22-87PC79818. Objective is to extend and optimize UOP`s single-stage slurry-catalyzed co-processing scheme, which was devleoped under previous Contract DE-AC22-84PC70002. Particular emphasis is given to defining and improving ssscatalyst utilization and costs, evaluating alternative and disposable slsurry-catalyst systems, and improving catalyst recycle and recovery techniques. Work during this quarter has concentrated on Tasks 3.1.1 (pilot plant modification), 3.1.2 (plant recertification), and 3.1.3 (reactor back-mixing study). Results of these tasks are discussed.
Date: August 23, 1989
Creator: Nafis, D.A.; Gatsis, J.G.; Lea, C. & Miller, M.A.
Partner: UNT Libraries Government Documents Department

Summary report for ITER task - T68: MHD facility preparation for Li/V blanket option

Description: A key feasibility issue for the ITER Vanadium/Lithium breeding blanket is the question of insulator coatings. Design calculations show that an electrically insulating layer is necessary to maintain an acceptably low MHD pressure drop. To enable experimental investigations of the MHD performance of candidate insulator materials and the technology for putting them in place, the room-temperature ALEX (Argonne`s Liquid Metal EXperiment) NaK facility was upgraded to a 300{degrees}C lithium system. The objective of this upgrade was to modify the existing facility to the minimum extent necessary, consistent with providing a safe, flexible, and easy to operate MHD test facility which uses lithium at ITER-relevant temperatures, Hartmann numbers, and interaction parameters. The facility was designed to produce MHD pressure drop data, test section voltage distributions, and heat transfer data for mid-scale test sections and blanket mockups. The system design description for this lithium upgrade of the ALEX facility is given in this document.
Date: August 1, 1995
Creator: Reed, C.B.; Haglund, R.C. & Miller, M.E.
Partner: UNT Libraries Government Documents Department

The development of solid methane neutron moderators at the Intense Pulsed Neutron Source facility of Argonne National Laboratory.

Description: The Intense Pulsed Neutron Source (IPNS) started using solid methane moderators in 1985 because of their efficient conversion (about 3.5 times greater than was achieved with a liquid hydrogen moderator) of fast neutrons to long wavelength neutrons. However, the solid methane moderators experienced numerous failures due to pressure surges caused by a combination of (1) the release of stored energy, which occurred when methane radiolytic products recombined, and (2) the expansion of hydrogen, which built up in the solid methane during irradiation. During the ensuing years studies were made to determine how to operate the solid methane moderators without causing failure. The rate at which stored energy built up during irradiation and the temperature at which hydrogen was released during annealing were determined. Since 1993 IPNS has successfully operated the solid methane moderators (at about 30 K) by periodically annealing to the liquid state around 90 K after every roughly three days of irradiation.
Date: March 10, 1999
Creator: Carpenter, J. M.; Miller, M. E. & Scott, T. L.
Partner: UNT Libraries Government Documents Department


Description: A single column model (SCM) is, in essence, an isolated grid column of a general circulation model (GCM). Hence, SCMs have rather demanding input data requirements, but do not suffer from problems associated with balance of a GCM. Among the initial conditions that must be used to describe the initial state of the SCM column are the vertical profile of the horizontal wind components and the vertical profiles of cloud water and ice. In addition, the large-scale divergence and advective tendencies of cloud water and ice must be supplied as external parameters. Finally, the liquid and ice cloud amount as a function of height within the SCM column are required for model evaluation. The scale of the SCM column over which the initial conditions, external parameters, and model evaluation fields must apply is relatively large ({approximately}300 km). To quantify atmospheric structure on this scale, the ARM SGP CART site is located within the NOAA wind profiler network and has boundary and extended measurement facilities in an area compatible with the scale requirements of SCMs. Over an area this size, however, there is often rich mesoscale structure. This mesoscale variability creates a sampling problem that can thwart even the most sophisticated attempts to quantify the initial conditions and external parameters, and to evaluate model performance. There are two approaches that can be used to quantify the time varying quantities required for SCMs: objective analysis and data assimilation. The latter relies on products produced for operational forecasting, while the former involves methods that can be used to combine measurements from various sources to produce synoptic descriptions of the large-scale dynamical and thermodynamic fields. Since data assimilation from operational models introduces the uncertainty of the parameterizations used in the models, most of the focus in the SCM effort has been on developing objective ...
Date: March 23, 1998
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, and (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 shown 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: January 1, 1994
Creator: Chen-Min; Less, K. & Miller, M.A.
Partner: UNT Libraries Government Documents Department

Dynamic stall occurrence on a horizontal axis wind turbine blade

Description: Surface pressure data from the National Renewable Energy Laboratory`s ``Combined Experiment`` were analyzed to provide a statistical representation of dynamic stall occurrence on a downwind horizontal axis wind turbine (HAWT). Over twenty thousand blade rotational cycles were each characterized at four span locations by the maximum leading edge suction pressure and by the azimuth, velocity, and yaw at which it occurred. Peak suction values at least twice that seen in static wind tunnel tests were taken to be indicative of dynamic stall. The occurrence of dynamic stall at all but the inboard station (30% span) shows good quantitative agreement with the theoretical limits on inflow velocity and yaw that should yield dynamic stall. Two hypotheses were developed to explain the discrepancy at 30% span. Estimates are also given for the frequency of dynamic stall occurrence on upwind turbines. Operational regimes were identified which minimize the occurrence of dynamic stall events.
Date: July 1, 1995
Creator: Shipley, D.E.; Miller, M.S. & Robinson, M.C.
Partner: UNT Libraries Government Documents Department


Description: Maintaining compliance with environmental regulatory requirements is a significant priority in successful completion of the Plutonium Finishing Plant (PFP) Nuclear Material Stabilization (NMS) Project. To ensure regulatory compliance throughout the deactivation and decommissioning of the PFP complex, an environmental regulatory strategy was developed. The overall goal of this strategy is to comply with all applicable environmental laws and regulations and/or compliance agreements during PFP stabilization, deactivation, and eventual dismantlement. Significant environmental drivers for the PFP Nuclear Material Stabilization Project include the Tri-Party Agreement; the Resource Conservation and Recovery Act of 1976 (RCRA); the Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA); the National Environmental Policy Act of 1969 (NEPA); the National Historic Preservation Act (NHPA); the Clean Air Act (CAA), and the Clean Water Act (CWA). Recent TPA negotiation s with Ecology and EPA have resulted in milestones that support the use of CERCLA as the primary statutory framework for decommissioning PFP. Milestones have been negotiated to support the preparation of Engineering Evaluations/Cost Analyses for decommissioning major PFP buildings. Specifically, CERCLA EE/CA(s) are anticipated for the following scopes of work: Settling Tank 241-Z-361, the 232-Z Incinerator, , the process facilities (eg, 234-5Z, 242, 236) and the process facility support buildings. These CERCLA EE/CA(s) are for the purpose of analyzing the appropriateness of the slab-on-grade endpoint Additionally, agreement was reached on performing an evaluation of actions necessary to address below-grade structures or other structures remaining after completion of the decommissioning of PFP. Remaining CERCLA actions will be integrated with other Central Plateau activities at the Hanford site.
Date: February 27, 2003
Creator: Hopkins, A.M.; Heineman, R.; Norton, S.; Miller, M. & Oates, L.
Partner: UNT Libraries Government Documents Department

Forensic Application of FM-CW and Pulse Radar

Description: Ground-penetrating radar (GPR) technology has supplied vital assistance in criminal investigations. However, law enforcement personnel desire further developments such that the technology is rapidly deployable, and that it provides both a simple user interface and sophisticated target identification. To assist in the development of target identification algorithms, our efforts involve gathering background GPR data for the various site conditions and circumstances that often typify clandestine burials. For this study, forensic anthropologists established shallow-grave plots at The University of Tennessee Anthropological Research Facility (ARF) that are specific to GPR research. These plots contain donated human cadavers lying in various configurations and depths, surrounded by assorted construction material and backfill debris. We scanned the plots using two GPR technologies: (1) a multi-frequency synthetic-aperture FM-CW radar (200-700 MHz) (GPR-X) developed by the U.S. Department of Energy's (DOE) Special Technologies Laboratory (STL), Bechtel Nevada (Koppenjan et al., 2000), and (2) a commercial pulse radar (SIR-20) manufactured by Geophysical Survey Systems, Inc. (400 and 900 MHz)(GSSI). The sweep-frequency data show the large biological mass decomposing within the torso as encircled ''hot spots.'' The 400-MHz pulse radar exhibit major horizontal reflectors above the body, with shadow reflectors (horizontal multiples) occurring beneath the body at 60 cm depth. The 400-MHz antenna was able to discern the grave walls and folded tarp covering the lower body. Under these moist, clay-rich conditions, the 900-MHz antenna was able to penetrate slightly beyond 30 cm beneath the concrete layer. However, neither system was able to penetrate beyond a one meter depth in the moist, clay-rich soil (fine, mixed, thermic Typic Paleudalf). Example scans from each system are provided, along with a discussion of the survey protocol and general performance.
Date: January 1, 2003
Creator: Koppenjan, S. K.; Freeland, R. S.; Miller, M. L. & Yoder, R. E.
Partner: UNT Libraries Government Documents Department

Simulation of beamline alignment operations

Description: The CORBA-based Simulator was a Laboratory Directed Research and Development (LDRD) project that applied simulation techniques to explore critical questions about distributed control systems. The simulator project used a three-prong approach that studied object-oriented distribution tools, computer network modeling, and simulation of key control system scenarios. The National Ignition Facility's (NIF) optical alignment system was modeled to study control system operations. The alignment of NIF's 192 beamlines is a large complex operation involving more than 100 computer systems and 8000 mechanized devices. The alignment process is defined by a detailed set of procedures; however, many of the steps are deterministic. The alignment steps for a poorly aligned component are similar to that of a nearly aligned component; however, additional operations/iterations are required to complete the process. Thus, the same alignment operations will require variable amounts of time to perform depending on the current alignment condition as well as other factors. Simulation of the alignment process is necessary to understand beamline alignment time requirements and how shared resources such as the Output Sensor and Target Alignment Sensor effect alignment efficiency. The simulation has provided alignment time estimates and other results based on documented alignment procedures and alignment experience gained in the laboratory. Computer communication time, mechanical hardware actuation times, image processing algorithm execution times, etc. have been experimentally determined and incorporated into the model. Previous analysis of alignment operations utilized average implementation times for all alignment operations. Resource sharing becomes rather simple to model when only average values are used. The time required to actually implement the many individual alignment operations will be quite dynamic. The simulation model estimates the time to complete an operation using distributions rather than static values. The only way to accurately understand resource utilization and time requirements for a complex industrial application such as alignment, is ...
Date: February 2, 1999
Creator: Annese, C & Miller, M G
Partner: UNT Libraries Government Documents Department

Effects of humoral factors on amplification of nonrecognizable erythrocytic and granulocytic precursors. [Rats, radiation effects on blood cell production]

Description: The purpose of these studies was to evaluate the effects of humoral factors on amplification of nonrecognizable erythrocytic and granulocytic precursors using the in vivo plasma clot diffusion chamber and the in vitro plasma clot culture methods. Plasma erythropoietin levels changes in the reticulocyte concentration and hematocrits of irradiated and non-irradiated Long-Evans rats exposed to hypoxia were also determined. While erythropoietin plasma levels appeared to effect BFU-E and CFU-E growth, results suggest erythropoietin may not be the sole regulator of red cell production and that inhibitors or chalone-like mechanisms may be involved. Measurements made on granulocyte precursors treated with CSF containing L-cell conditioned medium revealed granulocytic colonies and burst-like formations, similar to those seen for erythrocytic growth. There is strong evidence suggesting that CSF is a regulator of granulopoiesis; however, it is not the sole regulator and it appears that inhibitors may play an in vivo role. Growth of colonies with cell numbers not a power of 2 implies either asymmetric nitosis due to loss of genetic information required for continuing division, or differences in concentration of, or ability to recognize inhibitory factors. These possibilities are examined on the basis of results using in vivo and in vitro culture techniques.
Date: January 1, 1978
Creator: Cronkite, E P; Carsten, A L; Cohen, R; Miller, M E & Moccia, G
Partner: UNT Libraries Government Documents Department

Some target assay uncertainties for passive neutron coincidence counting

Description: This paper provides some target assay uncertainties for passive neutron coincidence counting of plutonium metal, oxide, mixed oxide, and scrap and waste. The target values are based in part on past user experience and in part on the estimated results from new coincidence counting techniques that are under development. The paper summarizes assay error sources and the new coincidence techniques, and recommends the technique that is likely to yield the lowest assay uncertainty for a given material type. These target assay uncertainties are intended to be useful for NDA instrument selection and assay variance propagation studies for both new and existing facilities. 14 refs., 3 tabs.
Date: January 1, 1990
Creator: Ensslin, N.; Langner, D.G.; Menlove, H.O.; Miller, M.C. & Russo, P.A.
Partner: UNT Libraries Government Documents Department

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 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 temperature studies with different concentrations of Mo slurry catalyst. The results of bench-scale Runs 26 and 27 are discussed in the following report. 25 figs.
Date: March 27, 1990
Creator: Nafis, D.A.; Gatsis, J.G.; Lea, C. & Miller, M.A.
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

Atom probe field ion microscopy and related topics: A bibliography 1989

Description: This bibliography includes references related to the following topics: atom probe field ion microscopy (APFIM), field ion spectroscopy (FIM), field emission microscopy (FEM), liquid metal ion sources (LMIS), scanning tunneling microscopy (STM), and theory. Technique-orientated studies and applications are included. This bibliography covers the period 1989. The references contained in this document were compiled from a variety of sources including computer searches and personal lists of publications.
Date: December 1, 1990
Creator: Miller, M.K.; Hawkins, A.R. & Russell, K.F.
Partner: UNT Libraries Government Documents Department

Active neutron multiplicity counting of bulk uranium

Description: This paper describes a new nondestructive assay technique being developed to assay bulk uranium containing kilogram quantities of {sup 235}U. The new technique uses neutron multiplicity analysis of data collected with a coincidence counter outfitted with AmLi neutron sources. We have calculated the expected neutron multiplicity count rate and assay precision for this technique and will report on its expected performance as a function of detector design characteristics, {sup 235 }U sample mass, AmLi source strength, and source-to-sample coupling. 11 refs., 2 figs., 2 tabs.
Date: January 1, 1991
Creator: Ensslin, N.; Krick, M.S.; Langner, D.G. & Miller, M.C.
Partner: UNT Libraries Government Documents Department

A high-efficiency neutron coincidence counter for small samples

Description: The inventory sample coincidence counter (INVS) has been modified to enhance its performance. The new design is suitable for use with a glove box sample-well (in-line application) as well as for use in the standard at-line mode. The counter has been redesigned to count more efficiently and be less sensitive to variations in sample position. These factors lead to a higher degree of precision and accuracy in a given counting period and allow for the practical use of the INVS counter with gamma-ray isotopics to obtain a plutonium assay independent of operator declarations and time-consuming chemicals analysis. A calculation study was performed using the Los Alamos transport code MCNP to optimize the design parameters. 5 refs., 7 figs., 8 tabs.
Date: January 1, 1991
Creator: Miller, M.C.; Menlove, H.O. & Russo, P.A.
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 effect of aging at 343 degrees C on type 308 stainless steel weldments

Description: The effect of long-term aging at intermediate temperatures on the mechanical properties of stainless steel welds has been studied. Three type 308 multipass shielded metal-arc welds with ferrite levels of 4, 8, and 12% were aged up to 343{degrees}C. Tensile tests showed little effect of aging on either the yield or ultimate tensile strengths, but the impact toughness was significantly degraded. The extent of the degradation increased with increasing ferrite content and increasing aging time. Examination of the microstructure with transmission electron microcscopy and atom probe field-ion microscopy revealed that the ferrite phase had undergone spinodal decomposition as a result of aging. In addition, G-phase particles were observed at dislocations, and finer G-phase particles were homogeneously distributed throughout the ferrite phase. The changes in the mechanical properties and the fractography are discussed in light of the observed changes in the microstructure. 19 refs., 7 figs., 2 tabs.
Date: January 1, 1990
Creator: Alexander, D.J.; Alexander, K.B.; Miller, M.K. & Nanstad, R.K.
Partner: UNT Libraries Government Documents Department

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

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