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An Experimental and Modeling-Based Study into the Ignition Delay Characteristics of Diesel Surrogate Binary Blend Fuels

An Experimental and Modeling-Based Study into the Ignition Delay Characteristics of Diesel Surrogate Binary Blend Fuels

Date: July 19, 2011
Creator: Carr, M A; Caton, P A; Hamilton, L J; Cowart, J S; Mehl, M & Pitz, W J
Description: Abstract not provided
Contributing Partner: UNT Libraries Government Documents Department
FINAL REPORT: Coupling Sorption to Soil Weathering During Reactive Transport: Impacts of Mineral Transformation and Sorbent Aging on Contaminant Speciation and Mobility

FINAL REPORT: Coupling Sorption to Soil Weathering During Reactive Transport: Impacts of Mineral Transformation and Sorbent Aging on Contaminant Speciation and Mobility

Date: March 21, 2009
Creator: O'Day, Peggy A.; Chorover, Jon; Mueller, Karl; Steefel, Carl & Serne, R. Jeff
Description: The goal of our project is a predictive-mechanistic understanding of the coupling between mineral weathering and contaminant (Cs, Sr, I) fate in caustic waste-impacted sediments at the Hanford Site. Through bench-scale experiments, we have identified geochemical transformations that alter the mobility of priority pollutants (Cs, Sr, I) in subsurface environments characteristic of high-level radioactive waste (HLRW)-impacted DoE sites. Our studies are designed to model the unique chemistry of this subsurface contamination, to quantify rates of contaminant uptake and release, and to identify molecular mechanisms of time-dependent, irreversible sequestration of contaminants into the solid phase. Our approach is to link quantitative macroscopic measures of contaminant mobility and partitioning to the molecular-scale mechanisms that mediate them. We have found that the molecular mechanisms themselves change with time and system composition in response to the evolving chemistry of contaminant-solution-mineral interactions. Specifically, our results show that contaminant fate is closely coupled to the major silicate incongruent weathering reactions that occur when soil solids are contacted with aqueous solutions under conditions that are far from equilibrium. Neoformed precipitates - including carbonate, feldspathoid and zeolite phases, have been observed to sequester Cs and Sr under caustic waste conditions. In contrast, iodide is less effectively sequestered into ...
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Photoelectrochemistry, Electronic Structure, and Bandgap Sizes of Semiconducting Cu(I)-Niobates and Cu(I)-Tantalates

Photoelectrochemistry, Electronic Structure, and Bandgap Sizes of Semiconducting Cu(I)-Niobates and Cu(I)-Tantalates

Date: November 14, 2013
Creator: Maggard, Paul A.
Description: Semiconducting metal-oxides have remained of intense research interest owing to their potential for achieving efficient solar-driven photocatalytic reactions in aqueous solutions that occur as a result of their bandgap excitation. The photocatalytic reduction of water or carbon dioxide to generate hydrogen or hydrocarbon fuels, respectively, can be driven on p-type (photocathodic) electrodes with suitable band energies. However, metal-oxide semiconductors are typically difficult to dope as p-type with a high mobility of carriers. The supported research led to the discovery of new p-type Cu(I)-niobate and Cu(I)-tantalate film electrodes that can be prepared on FTO glass. New high-purity flux syntheses and the full structural determination of several Cu(I)-containing niobates and tantalates have been completed, as well as new investigations of their optical and photoelectrochemical properties and electronic structures via density-functional theory calculations. For example, CuNbO3, Cu5Ta11O30 and CuNb3O8 were prepared in high purity and their structures were characterized by both single-crystal and powder X-ray diffraction techniques. These two classes of Cu(I)-containing compounds exhibit optical bandgap sizes ranging from ~1.3 eV to ~2.6 eV. Photoelectrochemical measurements of these compounds show strong photon-driven cathodic currents that confirm the p-type semiconductor behavior of CuNbO3, CuNb3O8, and Cu5Ta11O30. Incident-photon-to-current efficiencies are measured that approach greater than ...
Contributing Partner: UNT Libraries Government Documents Department
Physics with Rare Isotope Beams

Physics with Rare Isotope Beams

Date: November 8, 2013
Creator: Segel, Ralph E.
Description: Using stable and radioactive beams provided by ATLAS nuclear reactions of special interest in astrophysics have been studied with emphasis on breakout from the hot CNO cycle to the rp-process. The masses of nuclear fragments provided by a strong fission source have been measured in order to help trace the path of the r process. 8Li ions produced by the d(7Li,8Li)n reaction have been trapped and the electrons and alphas emitted in the ensuing beta-decay measured. The neutrino directions were therefore determined, which leads to a measurement of the electron-neutrino correlation. The energies and kinematics are such that a sensitive search for any tensor admixture could be performed and an upper limit of 0.6% was placed on any such admixture. Earlier work on the electromagnetic form factors of the proton was extended. Graduate students were active participants in all of these eperiments, which formed the basis for six PhD theses.
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PLUTONIA/CURIA COMPATIBILITY TESTING. Quarterly Report No. 9, October-- December 1970.

PLUTONIA/CURIA COMPATIBILITY TESTING. Quarterly Report No. 9, October-- December 1970.

Date: January 1, 1971
Creator: Andelin, R.L. & Watrous, J.D.
Description: None
Contributing Partner: UNT Libraries Government Documents Department
Plutonium-238 dioxide/T-111 compatibility studies

Plutonium-238 dioxide/T-111 compatibility studies

Date: September 19, 1975
Creator: Jones, G.J.; Selle, J.E. & Teaney, P.E.
Description: The tantalum-base alloy, T-111, is an ideal radioisotope encapsulant from the aspect of mechanical properties, but unfortunately undergoes severe oxygen embrittlement during long-term, high-temperature exposure to PuO$sub 2$. A study was undertaken in an effort to improve T-111/PuO$sub 2$ compatibility by testing the hypothesis that reduction of fuel stoichiometry to the range PuO$sub 1$.$sub 75$ to PuO$sub 1$.$sub 8$ would suspend the embrittlement process by producing a state of thermodynamic equilibrium within the capsule. Test temperatures ranged from 773 to 1373$sup 0$K, with aging times of 60 days, 240 days, and 2 y. The desired reaction did not proceed rapidly enough at the aging temperatures to stop T-111 embrittlement. Capsules heated above 1573$sup 0$K for 1 hr showed no signs of embrittlement during aging, even after 2 y at temperatures as high as 1173$sup 0$K. Results with test specimens employing pelletized fuel indicated the solid-state diffusion of oxygen from the fuel to the T-111 was the dominating transport process. In nonpretreated capsules oxygen diffusion in T-111 was the rate-controlling process. Pretreatment does result in the desired thermodynamic equilibrium at temperatures up to at least 1173$sup 0$K. (auth)
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PLUTONIUM AEROSOL PARTICLE SIZE DISTRIBUTIONS IN ROOM AIR

PLUTONIUM AEROSOL PARTICLE SIZE DISTRIBUTIONS IN ROOM AIR

Date: April 15, 1964
Creator: Anderson, B.V.
Description: None
Contributing Partner: UNT Libraries Government Documents Department
Final Report. DOE Computational Nanoscience Project DE-FG02-03ER46096: Integrated Multiscale Modeling of Molecular Computing Devices

Final Report. DOE Computational Nanoscience Project DE-FG02-03ER46096: Integrated Multiscale Modeling of Molecular Computing Devices

Date: November 15, 2009
Creator: Cummings, Peter
Description: The document is the final report of the DOE Computational Nanoscience Project DE-FG02-03ER46096: Integrated Multiscale Modeling of Molecular Computing Devices. It included references to 62 publications that were supported by the grant.
Contributing Partner: UNT Libraries Government Documents Department
Final report for DOE Grant No. DE-SC0006609 - Persistence of Microbially Facilitated Calcite Precipitation as an in situ Treatment for Strontium-90

Final report for DOE Grant No. DE-SC0006609 - Persistence of Microbially Facilitated Calcite Precipitation as an in situ Treatment for Strontium-90

Date: November 15, 2013
Creator: Smith, Robert W & Fujita, Yoshiko
Description: Subsurface radionuclide and metal contaminants throughout the U.S. Department of Energy (DOE) complex pose one of DOE?s greatest challenges for long-term stewardship. One promising stabilization mechanism for divalent ions, such as the short-lived radionuclide Sr-90, is co-precipitation in calcite. We have previously found that nutrient addition can stimulate microbial ureolytic activity, that this activity accelerates calcite precipitation and co-precipitation of Sr, and that higher calcite precipitation rates can result in increased Sr partitioning. We have conducted integrated field, laboratory, and computational research to evaluate the relationships between ureolysis and calcite precipitation rates and trace metal partitioning under environmentally relevant conditions, and investigated the coupling between flow/flux manipulations and precipitate distribution. A field experimental campaign conducted at the Integrated Field Research Challenge (IFRC) site located at Rifle, CO was based on a continuous recirculation design; water extracted from a down-gradient well was amended with urea and molasses (a carbon and electron donor) and re-injected into an up-gradient well. The goal of the recirculation design and simultaneous injection of urea and molasses was to uniformly accelerate the hydrolysis of urea and calcite precipitation over the entire inter-wellbore zone. The urea-molasses recirculation phase lasted, with brief interruptions for geophysical surveys, for 12 days ...
Contributing Partner: UNT Libraries Government Documents Department
Final Report for DUSEL R&D: BetaCage: A Screener of Ultra-Low-Level Radioactive Surface Contamination

Final Report for DUSEL R&D: BetaCage: A Screener of Ultra-Low-Level Radioactive Surface Contamination

Date: December 20, 2013
Creator: Golwala, Sunil R.
Description: The eventual full-size, radiopure BetaCage will be a low-background, atmospheric-pressure neon drift chamber with unprecedented sensitivity to emitters of low-energy electrons and alpha particles. We expect that the prototype BetaCage already developed will be an excellent screener of alpha particles. Both the prototype and final BetaCage will provide new infrastructure for rare-event science.
Contributing Partner: UNT Libraries Government Documents Department
PACIFIC NORTHWEST LABORATORY DIVISION OF ISOTOPE DEVELOPMENT PROGRAMS QUARTERLY REPORT: AUGUST--OCTOBER 1970.

PACIFIC NORTHWEST LABORATORY DIVISION OF ISOTOPE DEVELOPMENT PROGRAMS QUARTERLY REPORT: AUGUST--OCTOBER 1970.

Date: January 1, 1970
Creator: Hansen, J.E.
Description: None
Contributing Partner: UNT Libraries Government Documents Department
PACIFIC NORTHWEST LABORATORY DIVISION OF ISOTOPE DEVELOPMENT PROGRAMS. Quarterly Report, May--July 1970.

PACIFIC NORTHWEST LABORATORY DIVISION OF ISOTOPE DEVELOPMENT PROGRAMS. Quarterly Report, May--July 1970.

Date: January 1, 1970
Creator: Hansen, J.E. (ed.)
Description: None
Contributing Partner: UNT Libraries Government Documents Department
PACIFIC NORTHWEST LABORATORY DIVISION OF ISOTOPE DEVELOPMENT PROGRAMS. Quarterly Report, November 1969--January 1970.

PACIFIC NORTHWEST LABORATORY DIVISION OF ISOTOPE DEVELOPMENT PROGRAMS. Quarterly Report, November 1969--January 1970.

Date: January 1, 1970
Creator: Sheely, W.F. (ed.)
Description: None
Contributing Partner: UNT Libraries Government Documents Department
PACIFIC NORTHWEST LABORATORY, DIVISION OF ISOTOPES DEVELOPMENT PROGRAMS QUARTERLY REPORT: NOVEMBER--JANUARY 1970--71.

PACIFIC NORTHWEST LABORATORY, DIVISION OF ISOTOPES DEVELOPMENT PROGRAMS QUARTERLY REPORT: NOVEMBER--JANUARY 1970--71.

Date: January 1, 1971
Creator: Hansen, J.E.
Description: None
Contributing Partner: UNT Libraries Government Documents Department
Experimental Studies of Self Organization with Electron Plasmas

Experimental Studies of Self Organization with Electron Plasmas

Date: April 11, 2011
Creator: Matthaeus, William H.
Description: During the period of this grant we had a very active research effort in our group on the topic of 2D electron plasmas, relaxation, 2D Navier Stokes turbulence, and related issues. The project also motivated other studies we carried out such as a study of 2D turbulence with two-species vorticity.
Contributing Partner: UNT Libraries Government Documents Department
Florida Hydrogen Initiative

Florida Hydrogen Initiative

Date: June 30, 2013
Creator: Block, David L
Description: The Florida Hydrogen Initiative (FHI) was a research, development and demonstration hydrogen and fuel cell program. The FHI program objectives were to develop Florida?s hydrogen and fuel cell infrastructure and to assist DOE in its hydrogen and fuel cell activities The FHI program funded 12 RD&D projects as follows: Hydrogen Refueling Infrastructure and Rental Car Strategies -- L. Lines, Rollins College This project analyzes strategies for Florida's early stage adaptation of hydrogen-powered public transportation. In particular, the report investigates urban and statewide network of refueling stations and the feasibility of establishing a hydrogen rental-car fleet based in Orlando. Methanol Fuel Cell Vehicle Charging Station at Florida Atlantic University ? M. Fuchs, EnerFuel, Inc. The project objectives were to design, and demonstrate a 10 kWnet proton exchange membrane fuel cell stationary power plant operating on methanol, to achieve an electrical energy efficiency of 32% and to demonstrate transient response time of less than 3 milliseconds. Assessment of Public Understanding of the Hydrogen Economy Through Science Center Exhibits, J. Newman, Orlando Science Center The project objective was to design and build an interactive Science Center exhibit called: ?H2Now: the Great Hydrogen Xchange?. On-site Reformation of Diesel Fuel for Hydrogen Fueling Station Applications ...
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Numerical Optimization Algorithms and Software for Systems Biology

Numerical Optimization Algorithms and Software for Systems Biology

Date: February 2, 2013
Creator: Saunders, Michael
Description: The basic aims of this work are: to develop reliable algorithms for solving optimization problems involving large stoi- chiometric matrices; to investigate cyclic dependency between metabolic and macromolecular biosynthetic networks; and to quantify the significance of thermodynamic constraints on prokaryotic metabolism.
Contributing Partner: UNT Libraries Government Documents Department
SciDAC Center for Gyrokinetic Particle Simulation of Turbulent Transport in Burning Plasmas

SciDAC Center for Gyrokinetic Particle Simulation of Turbulent Transport in Burning Plasmas

Date: December 18, 2013
Creator: Lin, Zhihong
Description: During the first year of the SciDAC gyrokinetic particle simulation (GPS) project, the GPS team (Zhihong Lin, Liu Chen, Yasutaro Nishimura, and Igor Holod) at the University of California, Irvine (UCI) studied the tokamak electron transport driven by electron temperature gradient (ETG) turbulence, and by trapped electron mode (TEM) turbulence and ion temperature gradient (ITG) turbulence with kinetic electron effects, extended our studies of ITG turbulence spreading to core-edge coupling. We have developed and optimized an elliptic solver using finite element method (FEM), which enables the implementation of advanced kinetic electron models (split-weight scheme and hybrid model) in the SciDAC GPS production code GTC. The GTC code has been ported and optimized on both scalar and vector parallel computer architectures, and is being transformed into objected-oriented style to facilitate collaborative code development. During this period, the UCI team members presented 11 invited talks at major national and international conferences, published 22 papers in peer-reviewed journals and 10 papers in conference proceedings. The UCI hosted the annual SciDAC Workshop on Plasma Turbulence sponsored by the GPS Center, 2005-2007. The workshop was attended by about fifties US and foreign researchers and financially sponsored several gradual students from MIT, Princeton University, Germany, Switzerland, ...
Contributing Partner: UNT Libraries Government Documents Department
SEARCHING THE NUCLEAR SCIENCE ABSTRACTS DATA BASE BY USE OF THE BERKELEY MASS STORAGE SYSTEM.

SEARCHING THE NUCLEAR SCIENCE ABSTRACTS DATA BASE BY USE OF THE BERKELEY MASS STORAGE SYSTEM.

Date: January 1, 1971
Creator: Smith, G. L. & Herr, J. J.
Description: None
Contributing Partner: UNT Libraries Government Documents Department
Statistical Methods and Tools for Hanford Staged Feed Tank Sampling

Statistical Methods and Tools for Hanford Staged Feed Tank Sampling

Date: October 1, 2013
Creator: Fountain, Matthew S.; Brigantic, Robert T. & Peterson, Reid A.
Description: This report summarizes work conducted by Pacific Northwest National Laboratory to technically evaluate the current approach to staged feed sampling of high-level waste (HLW) sludge to meet waste acceptance criteria (WAC) for transfer from tank farms to the Hanford Waste Treatment and Immobilization Plant (WTP). The current sampling and analysis approach is detailed in the document titled Initial Data Quality Objectives for WTP Feed Acceptance Criteria, 24590-WTP-RPT-MGT-11-014, Revision 0 (Arakali et al. 2011). The goal of this current work is to evaluate and provide recommendations to support a defensible, technical and statistical basis for the staged feed sampling approach that meets WAC data quality objectives (DQOs).
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A STATISTICAL MODEL OF NUCLEAR LEVEL SPACINGS

A STATISTICAL MODEL OF NUCLEAR LEVEL SPACINGS

Date: December 1, 1960
Creator: Dresner, L. & Inonu, E.
Description: A generalization of Wigner's simple model for the distribution of nuclear level spacings is studied. The generalization is based on a stochastic process which reproduces the correct joint probabllity distribution of N energy levels for small spacings. The case N = 3, which includes the effect of the correlation between adjacent spacings, is discussed in detail. The resulting distribution and the correlation coefflcient are compared with experimental data. No definite conclusion can be drawn except that the effect of the correlations on the spacing distribution is very small. (auth)
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Ultra-High Intensity Magnetic Field Generation in Dense Plasma

Ultra-High Intensity Magnetic Field Generation in Dense Plasma

Date: January 8, 2014
Creator: Fisch, Nathaniel J
Description: I. Grant Objective The main objective of this grant proposal was to explore the efficient generation of intense currents. Whereasthefficient generation of electric current in low-­‐energy-­‐ density plasma has occupied the attention of the magnetic fusion community for several decades, scant attention has been paid to carrying over to high-­‐energy-­‐ density plasma the ideas for steady-­‐state current drive developed for low-­‐energy-­‐ density plasma, or, for that matter, to inventing new methodologies for generating electric current in high-­‐energy-­‐density plasma. What we proposed to do was to identify new mechanisms to accomplish current generation, and to assess the operation, physics, and engineering basis of new forms of current drive in regimes appropriate for new fusion concepts.
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Understanding the Subsurface Reactive Transport of Transuranic Contaminants at DOE Sites

Understanding the Subsurface Reactive Transport of Transuranic Contaminants at DOE Sites

Date: December 20, 2013
Creator: Barnett, Mark O.; Albrecht-Schmitt, Thomas E.; Saiers, James E. & Shuh, David K.
Description: Our primary hypothesis is that actinides can interact with surfaces in fundamentally different ways than other metals, metalloids, and oxyanions and that this fundamental difference requires new approaches to studying and modeling transuranic sorption to minerals and geomedia. This project supports a key mission of the SBR program to develop sufficient scientific understanding such that DOE sites will be able to incorporate coupled physical, chemical, and biological processes into decision making for environmental management and long-term stewardship, while also supporting DOE’s commitment to education, training, and collaboration with DOE user facilities.
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Technology to Facilitate the Use of Impaired Waters in Cooling Towers

Technology to Facilitate the Use of Impaired Waters in Cooling Towers

Date: April 30, 2012
Creator: Colborn, Robert
Description: The project goal was to develop an effective silica removal technology and couple that with existing electro-dialysis reversal (EDR) technology to achieve a cost effective treatment for impaired waters to allow for their use in the cooling towers of coal fired power plants. A quantitative target of the program was a 50% reduction in the fresh water withdrawal at a levelized cost of water of $3.90/Kgal. Over the course of the program, a new molybdenum-modified alumina was developed that significantly outperforms existing alumina materials in silica removal both kinetically and thermodynamically. The Langmuir capacity is 0.11g silica/g adsorbent. Moreover, a low cost recycle/regeneration process was discovered to allow for multiple recycles with minimal loss in activity. On the lab scale, five runs were carried out with no drop in performance between the second and fifth run in ability to absorb the silica from water. The Mo-modified alumina was successfully prepared on a multiple kilogram scale and a bench scale model column was used to remove 100 ppm of silica from 400 liters of simulated impaired water. Significant water savings would result from such a process and the regeneration process could be further optimized to reduce water requirements. Current barriers to ...
Contributing Partner: UNT Libraries Government Documents Department