Serial/Series Title
Clean Cities alternative fuel information series
8
Field Demonstration of a Membrane Process to Separate Nitrogen From Natural Gas Progress Report
7
Fiscal Year 2000
6
Evaluation of Roof Bolting Requirements Based on In-Mine Bolter Drilling Progress Report
5
Fiscal Year 2003
5
Investigation of Efficiency Improvements During CO2 Injection in Hydraulically and Naturally Fractured Reservoirs Progress Report
4
MUSC Environmental Biosciences Progress Report
4
National Bioenergy Center Biochemical Platform Integration Project Quarterly Update
4
Reducing Ultra-Clean Transportation Fuel Costs with HyMelt Hydrogen Quarterly Report
4
Science & Technology Review
4
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THE 2ND ERHIC WORKSHOP.
None
Date:
April 4, 2000
Creator:
Venugopalan, R. & Al, Et
Object Type:
Article
System:
The UNT Digital Library
3D Computations and Experiments
This project consists of two activities. Task A, Simulations and Measurements, combines all the material model development and associated numerical work with the materials-oriented experimental activities. The goal of this effort is to provide an improved understanding of dynamic material properties and to provide accurate numerical representations of those properties for use in analysis codes. Task B, ALE3D Development, involves general development activities in the ALE3D code with the focus of improving simulation capabilities for problems of mutual interest to DoD and DOE. Emphasis is on problems involving multi-phase flow, blast loading of structures and system safety/vulnerability studies.
Date:
April 5, 2004
Creator:
Couch, R; Faux, D; Goto, D & Nikkel, D
Object Type:
Report
System:
The UNT Digital Library
A 3D Frictional Segment-to-Segment Contact Method for Large Deformations and Quadratic Elements
Node-on-segment contact is the most common form of contact used today but has many deficiencies ranging from potential locking to non-smooth behavior with large sliding. Furthermore, node-on-segment approaches are not at all applicable to higher order discretizations (e.g. quadratic elements). In a previous work, [3, 4] we developed a segment-to-segment contact approach for eight node hexahedral elements based on the mortar method that was applicable to large deformation mechanics. The approach proved extremely robust since it eliminated the over-constraint that caused 'locking' and provided smooth force variations in large sliding. Here, we extend this previous approach to treat frictional contact problems. In addition, the method is extended to 3D quadratic tetrahedrals and hexahedrals. The proposed approach is then applied to several challenging frictional contact problems that demonstrate its effectiveness.
Date:
April 1, 2004
Creator:
Puso, M; Laursen, T & Solberg, J
Object Type:
Article
System:
The UNT Digital Library
3D Magnetotelluic characterization of the Coso GeothermalField
Electrical resistivity may contribute to progress inunderstanding geothermal systems by imaging the geometry, bounds andcontrolling structures in existing production, and thereby perhapssuggesting new areas for field expansion. To these ends, a dense grid ofmagnetotelluric (MT) stations plus a single line of contiguous bipolearray profiling has been acquired over the east flank of the Cosogeothermal system. Acquiring good quality MT data in producing geothermalsystems is a challenge due to production related electromagnetic (EM)noise and, in the case of Coso, due to proximity of a regional DCintertie power transmission line. To achieve good results, a remotereference completely outside the influence of the dominant source of EMnoise must be established. Experimental results so far indicate thatemplacing a reference site in Amargosa Valley, NV, 65 miles from the DCintertie, isstill insufficient for noise cancellation much of the time.Even though the DC line EM fields are planar at this distance, theyremain coherent with the nonplanar fields in the Coso area hence remotereferencing produces incorrect responses. We have successfully unwrappedand applied MT times series from the permanent observatory at Parkfield,CA, and these appear adequate to suppress the interference of thecultural EM noise. The efficacy of this observatory is confirmed bycomparison to stations taken using an ultra-distant …
Date:
April 23, 2007
Creator:
Newman, Gregory A.; Hoversten, G. Michael; Wannamaker, Philip E. & Gasperikova, Erika
Object Type:
Article
System:
The UNT Digital Library
3Q/4Q 2001 Annual M-Area and Metallurgical Laboratory Hazardous Waste Management Facilities Groundwater Monitoring and Corrective-Action Report - Annual 2001 - Volumes I and II
This report describes the groundwater monitoring and corrective-action program at the M-Area Hazardous Waste Management Facility (HWMF) and the Metallurgical Laboratory (Met Lab) HWMF at the Savannah River Site (SRS) during the third and fourth quarters of 2001. The report also provides a summary of the corrective-action program for the entire year. This program is required by South Carolina Resource Conservation and Recovery Act (RCRA) Hazardous Waste Permit SC1 890 008 989 and Section 264.100(g) of the South Carolina Hazardous Waste Management Regulations.
Date:
April 22, 2002
Creator:
Blas, J. F.
Object Type:
Report
System:
The UNT Digital Library
3Q/4Q00 Annual M-Area and Metallurgical Laboratory Hazardous Waste Management Facilities Groundwater Monitoring and Corrective-Action Report - Third and Fourth Quarters 2000 - Volumes I, II, and II
This report describes the groundwater monitoring and corrective-action program at the M-Area Hazardous Waste Management Facility (HWMF) and the Metallurgical Laboratory (Met Lab) HWMF at the Savannah River Site (SRS) during 2000. This program is required by South Carolina Resource Conservation and Recovery Act (RCRA) Hazardous Waste Permit SC1890008989 and Section 264.100(g) of the South Carolina Hazardous Waste Management Regulations.
Date:
April 17, 2001
Creator:
Cole, C.M. Sr.
Object Type:
Report
System:
The UNT Digital Library
3Q/4Q99 Annual M-Area and Metallurgical Laboratory Hazardous Waste Management Facilities Groundwater Monitoring and Corrective-Action Report - Third and Fourth Quarters 1999 - Volumes I, II, and III
This report describes the groundwater monitoring and corrective-action program at the M-Area Hazardous Waste Management Facility (HWMF) and the Metallurgical Laboratory (Met Lab) HWMF at the Savannah River Site (SRS) during 1999.
Date:
April 19, 2000
Creator:
Chase, J.
Object Type:
Report
System:
The UNT Digital Library
3rd year final contractor report for: U.S. Department of Energy Stewardship Science Academic Alliances Program Project Title: Detailed Measurements of Rayleigh-Taylor Mixing at Large and Small Atwood Numbers
This project had two major tasks: Task 1. The construction of a new air/helium facility to collect detailed measurements of Rayleigh-Taylor (RT) mixing at high Atwood number, and the distribution of these data to LLNL, LANL, and Alliance members for code validation and design purposes. Task 2. The collection of initial condition data from the new Air/Helium facility, for use with validation of RT simulation codes at LLNL and LANL. This report describes work done in the last twelve (12) months of the project, and also contains a summary of the complete work done over the three (3) life of the project. As of April 1, 2006, the air/helium facility (Task 1) is now complete and extensive testing and validation of diagnostics has been performed. Initial condition studies (Task 2) is also comp lete. Detailed experiments with air/helium with Atwood numbers up to 0.1 have been completed, and Atwood numbers of 0.25. Within the last three (3) months we have been able to successfully run the facility at Atwood numbers of 0.5. The progress matches the project plan, as does the budget. We have finished the initial condition studies using the water channel, and this work has been accepted for …
Date:
April 14, 2006
Creator:
Andrews, Malcolm J.
Object Type:
Report
System:
The UNT Digital Library
3w Transmitted Beam Diagnostic at the Omega Laser Facility
A 3{omega} transmitted beam diagnostic has been commissioned on the Omega Laser at the Laboratory for Laser Energetics, University of Rochester [Soures et.al., Laser Part. Beams 11 (1993)]. Transmitted light from one beam is collected by a large focusing mirror and directed onto a diagnostic platform. The near field of the transmitted light is imaged; the system collects information from twice the original f-cone of the beam. Two gated optical cameras capture the near field image of the transmitted light. Thirteen spatial positions around the measurement region are temporally resolved using fast photodiodes to allow a measure of the beam spray evolution. The Forward stimulated Raman scattering and forward simulated Brillion scattering are spectrally and temporally resolved at 5 independent locations within twice the original f-cone. The total transmitted energy is measured in two spectral bands ({delta}{lambda} < 400 nm and {delta}{lambda} > 400 nm).
Date:
April 24, 2006
Creator:
Froula, D. H.; Rekow, V.; Sorce, C.; Piston, K.; Knight, R.; Alvarez, S. et al.
Object Type:
Article
System:
The UNT Digital Library
59Fe(n,g)60Fe and 60Fe(n,g)61Fe Reaction Rates from Local Systematics
We present modeled neutron capture cross sections relevant to stellar production of {sup 60}Fe. Systematics for the input parameters required by the Hauser-Feshbach statistical model are developed based on measured data in the local region of the isotopic plane (20 {le} Z {le} 29, 43 {le} A {le} 65). These parameters and used to calculate reaction cross sections and rates for select target isotopes. Modeled cross sections are compared to experimental data where available. The {sup 59}Fe(n,{gamma}){sup 60}Fe and {sup 60}Fe(n, {gamma}){sup 61}Fe rates are compared to previous calculations. A brief discussion of errors related to the modeling is provided. We conclude by investigating the sensitivity of stellar production of {sup 26}Al and {sup 60}Fe to the {sup 59}Fe(n,{gamma}){sup 60}Fe and {sup 60}Fe(n,{gamma})61Fe reaction rates using a single zone model.
Date:
April 25, 2005
Creator:
Kelley, K; Hoffman, R D & Drake, M
Object Type:
Report
System:
The UNT Digital Library
661N1 and 661N3 Pre Shot Report
None
Date:
April 13, 2004
Creator:
Bosson, S T
Object Type:
Report
System:
The UNT Digital Library
6th Annual Systems Biology Symposium: Systems Biology and the Environment
Systems biology recognizes the complex multi-scale organization of biological systems, from molecules to ecosystems. The International Symposium on Systems Biology is an annual two-day event gathering the most influential researchers transforming biology into an integrative discipline investigating complex systems. In recognition of the fundamental similarity between the scientific problems addressed in environmental science and systems biology studies at the molecular, cellular, and organismal levels, the 2007 Symposium featured global leaders in “Systems Biology and the Environment.” The objective of the 2007 “Systems Biology and the Environment” International Symposium was to stimulate interdisciplinary thinking and research that spans systems biology and environmental science. This Symposium was well aligned with the DOE’s Genomics:GTL program efforts to achieve scientific objectives for each of the three DOE missions: • Develop biofuels as a major secure energy source for this century, • Develop biological solutions for intractable environmental problems, and • Understand biosystems’ climate impacts and assess sequestration strategies Our scientific program highlighted world-class research exemplifying these priorities. The Symposium featured 45 minute lectures from 12 researchers including: Penny/Sallie Chisholm of MIT gave the keynote address “Tiny Cells, Global Impact: What Prochlorococcus Can Teach Us About Systems Biology”, plus Jim Fredrickson of PNNL, Nitin Baliga …
Date:
April 1, 2007
Creator:
Galitski, Timothy, P.
Object Type:
Article
System:
The UNT Digital Library
70193-Influence of Clastic Dikes on Vertical Migration of Contaminants in the Vadose Zonde at Hanford
The purpose of this study was to examine the hypothesis that clastic dikes could form a preferential flow path through the vadose zone to the water table at the Hanford Site. Clastic dikes are subvertical structures that form within sedimentary sequences after deposition and cut across the original sedimentary layers. They are common throughout the Hanford Site, often occurring in organized polygonal networks. In the initial phase of the project, we analyzed the large-scale geometry of the clastic dikes and developed an algorithm for simulating their spatial distribution. This result will be useful in providing maps of the potential distribution of clastic dikes in areas where they are not exposed at the surface (e.g., where covered by windblown sand or construction of facilities like tank farms at the surface). In addition to the study of the large-scale distribution of the dikes, a major focus of the project was on field, laboratory, and modeling studies of the hydrogeological properties of the clastic dikes and the effect that they have on transport of water through the vadose zone. These studies were performed at two field locations at the Hanford Site. We performed an extensive series of field and laboratory measurements of a …
Date:
April 7, 2004
Creator:
Murray, Christopher J; Ward, Anderson L. & Wilson, John L.
Object Type:
Report
System:
The UNT Digital Library
7th Annual Systems Biology Symposium: Systems Biology and Engineering
Systems biology recognizes the complex multi-scale organization of biological systems, from molecules to ecosystems. The International Symposium on Systems Biology has been hosted by the Institute for Systems Biology in Seattle, Washington, since 2002. The annual two-day event gathers the most influential researchers transforming biology into an integrative discipline investingating complex systems. Engineering and application of new technology is a central element of systems biology. Genome-scale, or very small-scale, biological questions drive the enigneering of new technologies, which enable new modes of experimentation and computational analysis, leading to new biological insights and questions. Concepts and analytical methods in engineering are now finding direct applications in biology. Therefore, the 2008 Symposium, funded in partnership with the Department of Energy, featured global leaders in "Systems Biology and Engineering."
Date:
April 1, 2008
Creator:
Galitski, Timothy P.
Object Type:
Article
System:
The UNT Digital Library
AB INITIO AND CALPHAD THERMODYNAMICS OF MATERIALS
Ab initio electronic structure methods can supplement CALPHAD in two major ways for subsequent applications to stability in complex alloys. The first one is rather immediate and concerns the direct input of ab initio energetics in CALPHAD databases. The other way, more involved, is the assessment of ab initio thermodynamics {acute a} la CALPHAD. It will be shown how these results can be used within CALPHAD to predict the equilibrium properties of multi-component alloys.
Date:
April 14, 2004
Creator:
Turchi, P A
Object Type:
Article
System:
The UNT Digital Library
AB Initio Protein Tertiary Structure Prediction: Comparative-Genetic Algorithm with Graph Theoretical Methods
During the period from September 1, 1998 until September 1, 2000 I was awarded a Sloan/DOE postdoctoral fellowship to work in collaboration with Professor John Moult at the Center for Advanced Research in Biotechnology (CARB). Our research project, ''Ab Initio Protein Tertiary Structure Prediction and a Comparative Genetic algorithm'', yielded promising initial results. In short, the project is designed to predict the native fold, or native tertiary structure, of a given protein by inputting only the primary sequence of the protein (one or three letter code). The algorithm is based on a general learning, or evolutionary algorithm and is called Genetic Algorithm (GAS). In our particular application of GAS, we search for native folds, or lowest energy structures, using two different descriptions for the interactions of the atoms and residues in a given protein sequence. One potential energy function is based on a free energy description, while the other function is a threading potential derived by Moult and Samudrala. This modified genetic algorithm was loosely termed a Comparative Genetic Algorithm and was designed to search for native folded structures on both potential energy surfaces, simultaneously. We tested the algorithm on a series of peptides ranging from 11 to 15 residues …
Date:
April 20, 2001
Creator:
Gregurick, S. K.
Object Type:
Report
System:
The UNT Digital Library
Ab initio study of Al(III) adsorption on stepped {100} surfaces of KDP crystals
Crystals of potassium dihydrogen phosphate (KH{sub 2}PO{sub 4}, KDP) are grown in large scale for use as nonlinear material in laser components. Traces of trivalent metal impurities are often added to the supernatant to achieve habit control during crystal growth, selectively inhibiting the growth of the {l_brace}100{r_brace} face. Model systems representing AlPO{sub 4}-doped KDP {l_brace}100{r_brace} stepped surfaces are prepared and studied using ab initio quantum methods. Results of Hartree-Fock partial optimizations are presented, including estimated energies of ion pair binding to the steps. We find that the PO{sub 4}{sup 3-} ion takes a position not unlike that of a standard phosphate in the crystal lattice, while the aluminum atom is displaced far from a K{sup +} ion position to establish coordinations with the PO{sub 4}{sup 3-} ion and to bind with another lattice-bound phosphate. Our optimized structures suggest that it is the formation of a fourth coordination of Al(III) to a third phosphate ion from solution, or perhaps from a nearby position in the lattice, that disrupts further deposition, pinning the steps.
Date:
April 1, 2004
Creator:
Salter, E A; Wierzbicki, A & Land, T A
Object Type:
Article
System:
The UNT Digital Library
Ab initio study of low-energy electron collisions withtertafluoroethene, C2F4
We report the results of variational calculations of elastic electron scattering by tetrafluoroethene, C{sub 2}F{sub 4}, with incident electron energies ranging from 0.5 to 20 eV, using the complex Kohn method and effective core potentials. These are the first fully calculations to reproduce experimental angular differential cross sections at energies below 10 eV. Low-energy electron scattering by C{sub 2}F{sub 4} is sensitive to the inclusion of electronic correlation and target-distortion effects. We therefore present results that describe the dynamic polarization of the target by the incident electron. The calculated cross sections are compared with recent experimental measurements.
Date:
April 26, 2004
Creator:
Trevisan, C. S.; Orel, A. E. & Rescigno, Thomas N.
Object Type:
Article
System:
The UNT Digital Library
Ab initio study of optical absorption spectra of semiconductors and conjugated polymers
The effects of electron-hole interaction on the optical properties of a variety of materials have been calculated using an ab initio method based on solving the Bethe-Salpeter equation. Results on selected semiconductors, insulators, and semiconducting polymers are presented. In the cases of alpha-quartz (SiO2) and poly-phenylene-vinylene, resonant excitonic states qualitatively alter the absorption spectra.
Date:
April 30, 2000
Creator:
Tiago, M.L.; Chang, Eric K.; Rohlfing, Michael & Louie, Steven G.
Object Type:
Article
System:
The UNT Digital Library
Abelian Hidden Sectors at a GeV
We discuss mechanisms for naturally generating GeV-scale hidden sectors in the context of weak-scale supersymmetry. Such low mass scales can arise when hidden sectors are more weakly coupled to supersymmetry breaking than the visible sector, as happens when supersymmetry breaking is communicated to the visible sector by gauge interactions under which the hidden sector is uncharged, or if the hidden sector is sequestered from gravity-mediated supersymmetry breaking. We study these mechanisms in detail in the context of gauge and gaugino mediation, and present specific models of Abelian GeV-scale hidden sectors. In particular, we discuss kinetic mixing of a U(1){sub x} gauge force with hypercharge, singlets or bi-fundamentals which couple to both sectors, and additional loop effects. Finally, we investigate the possible relevance of such sectors for dark matter phenomenology, as well as for low- and high-energy collider searches.
Date:
April 16, 2009
Creator:
Morrissey, David E.; Poland, David; U., /Harvard; Zurek, Kathryn & U., /Fermilab /Michigan
Object Type:
Article
System:
The UNT Digital Library
Aberration-Coreected Electron Microscopy at Brookhaven National Laboratory
The last decade witnessed the rapid development and implementation of aberration correction in electron optics, realizing a more-than-70-year-old dream of aberration-free electron microscopy with a spatial resolution below one angstrom [1-9]. With sophisticated aberration correctors, modern electron microscopes now can reveal local structural information unavailable with neutrons and x-rays, such as the local arrangement of atoms, order/disorder, electronic inhomogeneity, bonding states, spin configuration, quantum confinement, and symmetry breaking [10-17]. Aberration correction through multipole-based correctors, as well as the associated improved stability in accelerating voltage, lens supplies, and goniometers in electron microscopes now enables medium-voltage (200-300kV) microscopes to achieve image resolution at or below 0.1nm. Aberration correction not only improves the instrument's spatial resolution but, equally importantly, allows larger objective lens pole-piece gaps to be employed thus realizing the potential of the instrument as a nanoscale property-measurement tool. That is, while retaining high spatial resolution, we can use various sample stages to observe the materials response under various temperature, electric- and magnetic- fields, and atmospheric environments. Such capabilities afford tremendous opportunities to tackle challenging science and technology issues in physics, chemistry, materials science, and biology. The research goal of the electron microscopy group at the Dept. of Condensed Matter Physics and …
Date:
April 1, 2008
Creator:
Zhu, Y. & Wall, J.
Object Type:
Book
System:
The UNT Digital Library
The Ability of the United States Federal Radiological Monitoring and Assessment Center to Collect and Disseminate Environmental Measurements during Radiological Emergencies
The Federal Radiological Monitoring and Assessment Center (FRMAC) is the United States’ response organization for radiological emergencies. The FRMAC is structured as an operations center and employs the combined resources of several federal agencies to respond to any disaster resulting in the release of radioactivity. The mission of the FRMAC is to support state and local authorities in the gathering of environmental data using an array of survey equipment ranging from alpha probes, beta/gamma probes, and high-purity germanium (HPGe) spectroscopy to the gathering of physical samples. Once collected, the data are projected on maps to assist public officials make protective action decisions. In addition to the accumulation of data, it is the legal obligation of the FRMAC to keep archival records of all data points and their actions. During an event, it is conceivable that hundreds to thousands of sample points will be recorded over a relatively short time. It is in the interest of the federal government and public that the information collected be put to the best use as fast as possible. Toward this end, the Remote Sensing Laboratory, working under the direction of the United States Department of Energy’s National Nuclear Security Administration, is investigating the use …
Date:
April 30, 2007
Creator:
Essex, Craig Marianno and James
Object Type:
Article
System:
The UNT Digital Library
Ablation of NIF Targets and Diagnostic Components by High Power Lasers and X-Rays from High Temperature Plasmas
The National Ignition Facility (NIF) will consist of 192 laser beams that have a total energy of up to 1.8 MJ in the 3rd harmonic ({lambda} = 0.35 {micro}m) with the amount of 2nd harmonic and fundamental light depending on the pulse shape. Material near best focus of the 3rd harmonic light will be vaporized/ablated very rapidly, with a significant fraction of the laser energy converted into plasma x rays. Additional plasma x rays can come from imploding/igniting capsule inside Inertial Confinement Fusion (ICF) hohlraums. Material from outer portions of the target, diagnostic components, first-wall material, and optical components, are ablated by the plasma x rays. Material out to a radius of order 3 cm from target center is also exposed to a significant flux of 2nd harmonic and fundamental laser light. Ablation can accelerate the remaining material to high velocities if it has been fragmented or melted. In addition, the high velocity debris wind of the initially vaporized material pushes on the fragments/droplets and increases their velocity. The high velocity shrapnel fragments/droplets can damage the fused silica shields protecting the final optics in NIF. We discuss modeling efforts to calculate vaporization/ablation, x-ray generation, shrapnel production, and ways to mitigate …
Date:
April 19, 2000
Creator:
Eder, D. C.; Anderson, A. T.; Braun, D. G. & Tobin, M. T.
Object Type:
Article
System:
The UNT Digital Library
About NICADD extruded scintillating strips
The results of control measurements of extruded scintillating strip responses to a radioactive source Sr-90 are provided, and details of strip choice, preparation, and method of measurement are included. About four hundred one meter long extruded scintillating strips were measured at four different points. These results were essential for prototyping a tail catcher and muon tracker for a future international electron positron linear collider detector.
Date:
April 1, 2005
Creator:
Dyshkant, A.; Beznosko, D.; Blazey, G.; Chakraborty, D.; Francis, K.; Kubik, D. et al.
Object Type:
Article
System:
The UNT Digital Library