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Analysis at the atomic level: The atom probe field-ion microscope

Description: The atom probe field-ion microscope (APFIM) is a unique analytical instrument that can analyze metals and semiconducting materials on the atomic scale. In recent years, the atom probe has developed into one of the most powerful instruments available for routine microstructural and microchemical analysis of materials. The types of investigations that have been performed have encompassed many diverse metallurgical subjects including phase transformations, segregation, diffusion, catalysis, and radiation damage. 3 refs., 3 figs.
Date: January 1, 1987
Creator: Miller, M.K.
Partner: UNT Libraries Government Documents Department

Nevada Test Site Area 25, Radiological Survey and Cleanup Project, 1974-1983 (a revised final report). Revision 1

Description: This report describes the radiological survey, decontamination and decommissioning (D and D) of the Nevada Test Site (NTS) Area 25 facilities and land areas incorporated in the Nuclear Rocket Development Station (NRDS). Buildings, facilities and support systems used after 1959 for nuclear reactor and engine testing were surveyed for the presence of radioactive contamination. The radiological survey portion of the project encompassed portable instrument surveys and removable contamination surveys (swipe) for beta plus gamma and alpha radioactive contamination of facilities, equipment and land areas. Soil sampling was also accomplished. The majority of Area 25 facilities and land areas have been returned to unrestricted use. Remaining radiologically contaminated areas are posted with warning signs and barricades. 9 references, 23 figures.
Date: December 1, 1984
Creator: Miller, M.G.
Partner: UNT Libraries Government Documents Department

PCB usage at the Grand Junction Area Office Facility. Final report

Description: The development, implementation, and results of the polychlorinated biphenyl (PCB) identification project at the Grand Junction Area Office (GJAO) are summarized. Methodology for the PCB analysis is described, and results are tabulated. Of the 51 transformers and disconnects in use at GJAO, 15 unites were determined to be PCB-contaminated or filled with PCBs. This number falls within EPA's estimate of 25 to 40 percent of all transformers in use being at least contaminated. Approximately 324 gallons of PCBs and 515 gallons of PCB-contaminated fluids are being used currently. No contaminated transformers or disconnects are in a position to contaminate food or feed products at the facility.
Date: June 1, 1982
Creator: Miller, M.E. & Donivan, S.
Partner: UNT Libraries Government Documents Department

Microstructural characterization of primary coolant pipe steel

Description: Atom probe field-ion microscopy, analytical electron microscopy, and optical microscopy have been used to investigate the changes that occur in the microstructure of cast CF 8 primary coolant pipe stainless steel after long term thermal aging. The cast duplex microstructure consisted of austenite with 15% delta-ferrite. Investigation of the aged material revealed that the ferrite spinodally decomposed into a fine scaled network of ..cap alpha.. and ..cap alpha..'. A fine G-phase precipitate was also observed in the ferrite. The observed degradation in mechanical properties is probably a consequence of the spinodal decomposition in the ferrite.
Date: January 1, 1986
Creator: Miller, M.K. & Bentley, J.
Partner: UNT Libraries Government Documents Department

Combined atom-probe and electron microscopy characterization of fine scale structures in aged primary coolant pipe stainless steel

Description: The capabilities and complementary nature of atom probe field-ion microscopy (APFIM) and analytical electron microscopy (AEM) for the characterization of fine-scale microstructures are illustrated by examination of the changes that occur after long term thermal aging of cast CF 8 and CF 8M duplex stainless steels. In material aged at 300 or 400/sup 0/C for up to 70,000 h, the ferrite had spinodally decomposed into a modulated fine-scaled interconnected network consisting of an iron-rich ..cap alpha.. phase and a chromium-enriched ..cap alpha..' phase with periodicities of between 2 and 9 nm. G-phase precipitates 2 to 10 nm in diameter were also observed in the ferrite at concentrations of more than 10/sup 21/ m/sup -3/. The reported degradation in mechanical properties is most likely a consequence of the spinodal decomposition in the ferrite.
Date: January 1, 1986
Creator: Bentley, J. & Miller, M.K.
Partner: UNT Libraries Government Documents Department

An atom probe study of phase decomposition in three iron meteorites

Description: An atom probe field-ion microscopy characterization of the Cape York, Twin City and Santa Catharina iron-nickel meteorites has been performed. This investigation has revealed that the taenite, corresponding to an interface region between the cloudy zone and the clear taenite 2 (CT2) region in the Cape York meteorite and the matrix of the Twin City and Santa Catharina meteorites, has phase separated to form an ultra-fine scale duplex microstructure. The composition of these two phases was determined to be 50 at. % Ni and approximately 15 at. % Ni. These compositions correspond to the equiatomic FeNi L1/sub 0/-ordered phase and a disordered face centered cubic phase. 38 refs., 16 figs., 3 tabs.
Date: January 1, 1989
Creator: Miller, M.K. & Russell, K.F.
Partner: UNT Libraries Government Documents Department

On the diurnal characteristics of cloud structure in the marine stratocumulus transition regime

Description: It is known that stratus-topped marine boundary layers in the mid- latitudes are subject to significant diurnal changes in structure caused by solar heating. One characteristic of the transition cloud regime that has been thoroughly explored is its diurnal variability. Although this variability has been discussed in other studies, the size of the database was restrictive. Thus, it is of importance to examine the diurnal characteristics of transition cloud structure in a larger data sample to validate the conclusions of these previous studies and to enhance our understanding of the effects of this diurnal variability on the climatology of the transition itself. The Atlantic Stratocumulus Transition Experiment (ASTEX) was designed to help understand transition clouds by making comprehensive measurements of their structure over a one-month period. Data was collected using a suite of in-situ and surface-based remote sensors deployed on the island of Santa Maria.
Date: July 1, 1996
Creator: Miller, M.A.
Partner: UNT Libraries Government Documents Department

Developing high-performance cross-functional teams: Understanding motivations, functional loyalties, and teaming fundamentals

Description: Teamwork is the key to the future of effective technology management. Today`s technologies and markets have become too complex for individuals to work alone. Global competition, limited resources, cost consciousness, and time pressures have forced organizations and project managers to encourage teamwork. Many of these teams will be cross-functional teams that can draw on a multitude of talents and knowledge. To develop high-performing cross-functional teams, managers must understand motivations, functional loyalties, and the different backgrounds of the individual team members. To develop a better understanding of these issues, managers can learn from experience and from literature on teams and teaming concepts. When studying the literature to learn about cross-functional teaming, managers will find many good theoretical concepts, but when put into practice, these concepts have varying effects. This issue of varying effectiveness is what drives the research for this paper. The teaming concepts were studied to confirm or modify current understanding. The literature was compared with a {open_quotes}ground truth{close_quotes}, a survey of the reality of teaming practices, to examine the teaming concepts that the literature finds to be critical to the success of teams. These results are compared to existing teams to determine if such techniques apply in real-world cases.
Date: August 1, 1996
Creator: Miller, M.A.
Partner: UNT Libraries Government Documents Department

Energy Savers: Cool Summer Tips

Description: A tri-fold brochure addressing energy-saving tips for homeowners ranging from low- or no-cost suggestions to higher cost suggestions for longer-term savings. Cooling, windows, weatherizing, and landscaping are addressed.
Date: June 18, 2001
Creator: Miller, M.
Partner: UNT Libraries Government Documents Department

Atom Probe Tomography Characterization of the Solute Distributions in a Neutron-Irradiated and Annealed Pressure Vessel Steel Weld

Description: A combined atom probe tomography and atom probe field ion microscopy study has been performed on a submerged arc weld irradiated to high fluence in the Heavy-Section Steel irradiation (HSSI) fifth irradiation series (Weld 73W). The composition of this weld is Fe - 0.27 at. % Cu, 1.58% Mn, 0.57% Ni, 0.34% MO, 0.27% Cr, 0.58% Si, 0.003% V, 0.45% C, 0.009% P, and 0.009% S. The material was examined after five conditions: after a typical stress relief treatment of 40 h at 607 C, after neutron irradiation to a fluence of 2 x 10{sup 23} n m{sup {minus}2} (E > 1 MeV), and after irradiation and isothermal anneals of 0.5, 1, and 168 h at 454 C. This report describes the matrix composition and the size, composition, and number density of the ultrafine copper-enriched precipitates that formed under neutron irradiation and the change in these parameters with post-irradiation annealing treatments.
Date: January 30, 2001
Creator: Miller, M.K.
Partner: UNT Libraries Government Documents Department

Neutron detection and multiplicity counting using a boron-loaded plastic scintillator/bismuth germanate phoswich detector array

Description: Neutron detection and multiplicity counting has been investigated using a boron-loaded plastic scintillator/bismuth germanate phoswich detector array. Boron-loaded plastic combines neutron moderation (H) and detection ({sup 10}B) at the molecular level, thereby physically coupling increasing detection efficiency and decreasing die-away time with detector volume. Both of these characteristics address a fundamental limitation of thermal-neutron multiplicity counters, where {sup 3}He proportional counters are embedded in a polyethylene matrix. Separation of the phoswich response into its plastic scintillator and bismuth germanate components was accomplished on a pulse-by-pulse basis using custom integrator and timing circuits. In addition, a custom time-tag module was used to provide a time for each detector event. Analysis of the combined energy and time event stream was performed by calibrating each detector`s response and filtering based on the presence of a simultaneous energy deposition corresponding to the {sup 10}B(n,alpha) reaction products in the plastic scintillator (93 keV{sub ee}) and the accompanying neutron-capture gamma ray in the bismuth germanate (478 keV). Time-correlation analysis was subsequently performed on the filtered event stream to obtain shift-register-type singles and doubles count rates. Proof-of-principle measurements were conducted with a variety of gamma-ray and neutron sources including {sup 137}Cs, {sup 54}Mn, AmLi, and {sup 252}Cf. Results of this study indicate that a neutron-capture probability of {approximately}10% and a die-away time of {approximately}10 {micro}s are possible with a 4-detector array with a detector volume of 1600 cm{sup 3}. Simulations were performed that indicate neutron-capture probabilities on the order of 50% and die-away times of less than 4 {micro}s are realistically achievable. While further study will be required for practical application of such a detection system, the results obtained in this investigation are encouraging and may lead to a new class of high-efficiency, short die-away time neutron multiplicity counters capable of extending current nondestructive assay methods for ...
Date: March 1998
Creator: Miller, M. C.
Partner: UNT Libraries Government Documents Department


Description: In 1978, on the basis of existing health studies at the time, the Uranium Mill Tailings Remedial Action (UMTRA) Project legislation was proposed that would authorize remedial action at inactive uranium processing sites and vicinity properties. The cost of the program to the Federal Government was expected to be $180 million. With the completion of this project, approximately 1300 theoretical cancer deaths were prevented in the next 100 years at a cost of $1.45 billion, based on the Fiscal Year 1998 Federal UMTRA budget. The individual site costs ranged from $0.2 million up to $18 billion spent per theoretical cancer death averted over the next 100 years. Resources required to sustain remediation activities such as this are subject to reduction over time, and are originally based on conservative assumptions that tend to overestimate risks to the general public. This evaluation used a process incorporating risk-based corrective action (RBCA); a three-tiered, decision-making process tailoring corrective action activities according to site-specific conditions and risks. If RBCA had been applied at the start of the UMTRA Project, and using a criterion of >1 excess cancer death prevented as justification to remediate the site, only 50% of the existing sites would have been remediated, yielding a cost savings of $303.6 million to the Federal Government and affected States, which share 10% of the cost. This cost savings equates to 21% of the overall project budget. In addition, only 22% of the vicinity properties had structural contamination contributing to elevated interior gamma exposure and radon levels. Focusing only on these particular properties could have saved an additional $269.3 million, yielding a total savings of $573 million; 40% of the overall project budget. As operational experience is acquired, including greater understanding of the radiological and nonradiological risks, decisions should be based on the RBCA process, rather ...
Date: February 25, 2002
Creator: Miller, M. L. & Hylko, J. M.
Partner: UNT Libraries Government Documents Department

Microstructural characterization of irradiated PWR steels using the atom probe field-ion microscope

Description: Atom probe field-ion microscopy has been used to characterize the microstructure of a neutron-irradiated A533B pressure vessel steel weld. The atomic spatial resolution of this technique permits a complete structural and chemical description of the ultra-fine features that control the mechanical properties to be made. A variety of fine scale features including roughly spherical copper precipitates and clusters, spherical and rod-shaped molybdenum carbide and disc-shaped molybdenum nitride precipitates were observed to be inhomogeneously distributed in the ferrite. The copper content of the ferrite was substantially reduced from the nominal level. A thin film of molybdenum carbides and nitrides was observed on grain boundaries in addition to a coarse copper-manganese precipitate. Substantial enrichment of manganese and nickel were detected at the copper-manganese precipitate-ferrite interface and this enrichment extended into the ferrite. Enrichment of nickel, manganese and phosphorus were also measured at grain boundaries.
Date: August 1, 1987
Creator: Miller, M.K. & Burke, M.G.
Partner: UNT Libraries Government Documents Department

Hanford environmental CaF2:Mn thermoluminescent dosimeter

Description: The TLD-400 chips combined with the Pb-Ta field capsule provide a sensitive method of measuring penetrating ambient radiation in the environment. The method is best used for field deployments of about 1 month or less to minimize problems associated with fading. A correction factor of about 10% is necessary for the readings obtained for a 28-day field deployment and a 1-day wait before readout. Integration of reader output from 150/sup 0/C to 280/sup 0/C provides a good signal-to-noise ratio for TLD-400 chips exposed to 5 mR for the reader and planchet described herein. Visual inspection of the glow curves is recommended during startup of any new program or following any major instrument repair. The glow curves can be easily drawn with an X-Y recorder. Because of the large energy dependence of bare TLD-400 chips, an energy-flattening filter is necessary to allow a direct conversion from a reference exposure to observed field exposures. The field capsule used, consisting of 10 mil of tantalum and 2 mil of lead, provides an approximate uniform energy response above 70 keV. Below 70 keV, the response decreases rapidly because of the shielding. Experiments conducted have not shown the TLD-400 chips to be sensitive to the extremes of summer temperature (approximately 50/sup 0/C) occasionally encountered at Hanford. Although the field dosimeter exhibits a directional dependence, this is of primary concern during calibration, in which the axis of the dosimeter should be normal to the photon beam. The procedures used to interpret the TLD chip reader output in terms of dose are fully described in the text.
Date: March 1, 1978
Creator: Fix, J.J. & Miller, M.L.
Partner: UNT Libraries Government Documents Department

An Accurate Method of Measuring the Moments of Inertia of Airplanes

Description: From Summary: "This note contains a description of an improved apparatus and procedure used by the NACA for determining the moments of inertia of airplanes. The method used, based on the pendulum theory, is similar to that previously used, but a recent investigation of its accuracy has resulted in the improvements described herein. The error, when using the new apparatus and procedure, has been found to be of the order of 1 per cent."
Date: October 1930
Creator: Miller, M. P.
Partner: UNT Libraries Government Documents Department

Plutonium process control using an advanced on-line gamma monitor for uranium, plutonium, and americium

Description: An on-line gamma monitor has been developed to profile uranium, plutonium, and americium in waste and product streams of the anion exchange process used to recover and purify plutonium at the Los Alamos Plutonium Facility. The gamma monitor employs passive gamma spectrometry to measure /sup 241/Am and /sup 239/Pu, based on their 59.5-keV and 129-keV gamma rays, respectively. Because natural and depleted uranium present in typical process streams have no gamma rays suitable for measurement by such passive methods, uranium measurement requires a novel and less direct technique. Plutonium-241, which is always present in plutonium processed at Los Alamos, decays primarily by beta emission to form /sup 241/Am. However, a small fraction of /sup 241/Pu decays by alpha emission to 6.8-day /sup 237/U. The short half-life and 208-keV gamma energy of /sup 237/U make it an ideal radiotracer to mark the position of macro amounts of uranium impurity in the separation process. The real-time data obtained from an operating process allow operators to optimize many process parameters. The gamma monitor also provides a permanent record of the daily performance of each ion exchange system. 2 refs., 12 figs.
Date: May 1, 1987
Creator: Marsh, S.F. & Miller, M.C.
Partner: UNT Libraries Government Documents Department

Green Pricing Program Marketing Expenditures: Finding the Right Balance

Description: In practice, it is difficult to determine the optimal amount to spend on marketing and administering a green pricing program. Budgets for marketing and administration of green pricing programs are a function of several factors: the region of the country; the size of the utility service area; the customer base and media markets encompassed within that service area; the point or stage in the lifespan of the program; and certainly, not least, the utility's commitment to and goals for the program. All of these factors vary significantly among programs. This report presents data on programs that have funded both marketing and program administration. The National Renewable Energy Laboratory (NREL) gathers the data annually from utility green pricing program managers. Programs reporting data to NREL spent a median of 18.8% of program revenues on marketing their programs in 2008 and 16.6% in 2007. The smallest utilities (those with less than 25,000 in their eligible customer base) spent 49% of revenues on marketing, significantly more than the overall median. This report addresses the role of renewable energy credit (REC) marketers and start-up costs--and the role of marketing, generally, in achieving program objectives, including expansion of renewable energy.
Date: September 1, 2009
Creator: Friedman, B. & Miller, M.
Partner: UNT Libraries Government Documents Department

Silo & HDF5 I/O Scaling Improvements on BG/P Systems

Description: Silo and HDF5 are I/O libraries used by many codes important to the LLNL's Weapons and Complex Integration (WCI) mission. In the past year, modest adjustments and tuning of Silo, HDF5 and the I/O configuration of the BG/P platform, Dawn, were undertaken. A key goal of this work was to improve I/O performance without requiring any changes in the application codes themselves. In particular, the application codes have been allowed to continue to use a simplified yet highly flexible I/O paradigm known as 'Poor Man's Parallel I/O', where scalability is achieved through concurrent, serial I/O to multiple files. The results demonstrate substantial performance gains (better than 50x in many cases) at large scale (greater than 64,000 MPI tasks). They describe key enhancements made to Silo, HDF5 and the I/O configuration of our BG/P platform and present very favorable results from scalability studies over a wide range of operating scenarios.
Date: December 2, 2010
Creator: Collette, M R & Miller, M C
Partner: UNT Libraries Government Documents Department

Oil recovery from naturally fractured reservoirs by steam injection methods

Description: The objective of this study is to develop accurate models for predicting oil recovery in naturally fractured reservoirs by steam injection. This objective is being met through an integrated experimental, numerical, and analytical study of the recovery mechanisms that control oil recovery for this process. These mechanisms include capillary imbibition, thermal expansion, gas generation from chemical reactions, and temperature-dependent thermal properties.
Date: January 1, 1991
Creator: Reis, J. & Miller, M.
Partner: UNT Libraries Government Documents Department

Effect of Prudhoe crude oil on carbon assimilation by planktonic algae in an arctic pond

Description: During the summer of 1975, 240ml/m of Prudhoe crude oil was spilled on an experimental coastal pond similar to those around Prudhoe Bay. Deviaton of algal production, algal biomass and species composition was compared to an adjacent control pond. Planktonic primary productivity was initially inhibited but recovered. Algal density did not deviate in the two ponds; however, the biomass and the species composition was changed, by the elimination of the Cryptophyte Rhodomonas minuta. The time course of the effects was related to the weathering and degradation of the oil. On these ponds the effects on the phytoplankton were not significantly different than those observed in 1970 after a controlled spill at 45 times the 1975 dose rate.
Date: January 1, 1975
Creator: Miller, M.C.; Hater, G.R. & Vestal, J.R.
Partner: UNT Libraries Government Documents Department