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20-TeV colliding-beam facilities
In March, a workshop was held at Cornell University on the accelerator. The conclusion of this workshop was that a 20 TeV on 20 TeV proton-proton collider is technically feasable, that construction could begin after 2.5 to 4 years of research and development, and the cost would be 1.3 to 2 billion dollars. To put this machine into perspective one must consider the existing facilities listed in table I. There are about 23 high energy physics laboratories in the world that are being operated or constructed. Most of these labs have an effective energy of less than 100 GeV and study principally the known quarks and leptons. The only accelerator operating at an effective energy greater than 100 GeV is the CERN proton-antiproton system. As has been presented at this conference in other papers their success has been great in a very short time, the discovery of the vector bosons W and Z. The only machine approved that will have an effective energy greater than 1000 GeV is the Russian accelerator UNK. The effective energy of a 20 TeV on 20 TeV proton-proton collider would be about 15 TeV.
Date:
September 15, 1983
Creator:
Huson, F.R.
Object Type:
Report
System:
The UNT Digital Library
District heating and cooling systems for communities through power plant retrofit and distribution network. Final report. Volume II. Appendices
This appendix presents tabulated data used for evaluating the feasibility of retrofitting thermal power plants in the Detroit area so as to provide heat for a district heating system. (LCL)
Date:
September 15, 1979
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Site Environmental Report for 2007 Volume I
The Site Environmental Report is an integrated report on Berkeley Lab's environmental programs to satisfy the requirements of DOE Order 231.1A, Environment, Safety, and Health Reporting. It summarizes Berkeley Lab's environmental management performance, presents environmental monitoring results, and describes significant programs for calendar year 2007. Volume I is organized into an executive summary followed by six chapters that contain an overview of the Laboratory, a discussion of the Laboratory's environmental management system, the status of environmental programs, and summarized results from surveillance and monitoring activities.
Date:
September 15, 2008
Creator:
Lackner, Regina E.; Baskin, David; Fox, Robert; Jelinski, John; Pauer, Ron; Thorson, Patrick et al.
Object Type:
Report
System:
The UNT Digital Library
2007 Plant Metabolic Engineering Gordon Conference and Graduate Research Seminar
Plant Metabolic Engineering is an emerging field that integrates a diverse range of disciplines including plant genetics, genomics, biochemistry, chemistry and cell biology. The Gordon-Kenan Graduate Research Seminar (GRS) in Plant Metabolic Engineering was initiated to provide a unique opportunity for future researcher leaders to present their work in this field. It also creates an environment allowing for peer-review and critical assessment of work without the intimidation usually associated with the presence of senior investigators. The GRS immediately precedes the Plant Metabolic Engineering Gordon Research Conference and will be for and by graduate students and post-docs, with the assistance of the organizers listed.
Date:
September 15, 2008
Creator:
Grotewold, Erich
Object Type:
Article
System:
The UNT Digital Library
Evaluation of production samples of the scintillators LaBr3:Ce and LaCl3:Ce
We report on the evaluation of the performance of two recently developed scintillator materials, LaCl{sub 3}:Ce and LaBr{sub 3}:Ce, at the task of gamma ray spectroscopy. Their performance is compared to a standard scintillator used for gamma ray spectroscopy--a 25 mm diameter 25 mm tall cylinder of NaI:Tl. We measure the pulse height, energy resolution, and full-energy efficiency of production LaBr{sub 3}:Ce and LaCl{sub 3}:Ce scintillation crystals of different sizes and geometries for a variety of gamma-ray energies. Using production rather than specially selected crystals will establish whether immediate large-scale use is feasible. The crystal is excited by gamma rays from one of six isotopic sources ({sup 125}I, {sup 241}Am, {sup 57}Co, {sup 22}Na, {sup 137}Cs, and {sup 60}Co) placed 15 cm away from the scintillator. Our measurements show that both LaCl{sub 3} and LaBr{sub 3} outperform NaI:Tl in almost all cases. They outperform NaI:Tl at all energies for the photopeak fraction and counting rate measurements, and for energy resolution at higher energies (above 200 keV for LaCl{sub 3} and 75 keV for LaBr{sub 3}). The performance of production crystals is excellent and these scintillators should be considered for immediate use in systems where stopping power and energy resolution are …
Date:
September 15, 2005
Creator:
Choong, Woon-Seng; Derenzo, Stephen E. & Moses, William W.
Object Type:
Article
System:
The UNT Digital Library
Chemical Methods for the Production of Proteins
The goal of this research program was to develop improved methods for chemical peptide and protein synthesis, and to apply these methods to the total synthesis of small proteins (<80 amino acids) & integral membrane proteins.
Date:
September 15, 2008
Creator:
Kent, Stephen B. H.
Object Type:
Report
System:
The UNT Digital Library
The effect of temperature on the speciation of U(VI) in sulfate solutions
Sulfate, one of the inorganic constituents that could be present in the nuclear waste repository, forms complexes with U(VI) and affects its migration in the environment. Results show that the complexation of U(VI) with sulfate is enhanced by the increase in temperature. The effect of temperature on the complexation and speciation of U(VI) in sulfate solutions is discussed.
Date:
September 15, 2008
Creator:
Rao, Linfeng & Tian, Guoxin
Object Type:
Book
System:
The UNT Digital Library
Summary of the Hanford Site Environmental Report for Calendar Year 2006
This booklet summarizes the Hanford Site Environmental Report for Calendar Year 2006.
Date:
September 15, 2007
Creator:
Hanf, Robert W.; Poston, Ted M. & Dirkes, Roger L.
Object Type:
Report
System:
The UNT Digital Library
ABSTRACT: Design of Groundwater Monitoring Networks Considering Conceptual Model and Parametric Uncertainty
Uncertainty built into conceptual groundwater flow and transport models and associated parametric uncertainty should be appropriately included when such models are used to develop detection monitoring networks for contaminated sites. We compare alternative approaches of propagating such uncertainty from the flow and transport model into the network design. The focus is on detection monitoring networks where the primary objective is to intercept the contaminant before it reaches a boundary of interest (e.g., compliance boundary). Different uncertainty propagation approaches identify different well locations and different well combinations (networks) as having the highest detection efficiency. It is thus recommended that multiple uncertainty propagation approaches are considered. If several approaches yield consistent results in terms of identifying the best performing candidate wells and the best performing well network for detecting a contaminant plume, this would provide confidence in the suitability of the selected well locations.
Date:
September 15, 2008
Creator:
Hassan, A.; Bekhit, H.; Zhang, Y. & Chapman, J.
Object Type:
Article
System:
The UNT Digital Library
Probing Interactions at the Nanoscale: Sensing Protein Molecules
Introduction We have developed a high-frequency electronic biosensor of parallel-plate geometry that is embedded within a microfluidic device. This novel biosensor allows us to perform dielectric spectroscopy on a variety of biological samples—from cells to molecules—in solution. Because it is purely electronic, the sensor allows for rapid characterization with no sample preparation or chemical alteration. In addition, it is capable of probing length scales from millimeters to microns over a frequency range 50 MHz to 40 GHz, and sample volumes as small as picoliters [1,2]. Our high-frequency biosensor has evolved from previous device designs based on a coplanar waveguide (CPW) geometry [2]. For our current device, we employ microfluidic tectonics (µFT) [3] to embed two microstrip conductors within a microfluidic channel. The electronic coupling between the two conductors is greater than in our previous CPW design and more importantly, leads to an enhanced sensitivity. Our utilization of µFT allows us to incorporate easily this high-frequency electronic biosensor with a variety of lab-on-a-chip architectures. Device Description Figure 1 is a schematic of our high-frequency electronic biosensor. We fabricate this sensor by first depositing a 500 Å seed layer of gold onto two glass microscope slides. We then use photolithography to pattern …
Date:
September 15, 2003
Creator:
Sohn, Lydia; Weiss, Ron & Tavazoie, Saeed
Object Type:
Report
System:
The UNT Digital Library
Microbial Effects on NuclearWaste Packaging Materials
None
Date:
September 15, 2005
Creator:
Horn, J; Martin, S; Carillo, C & Lian, T
Object Type:
Report
System:
The UNT Digital Library
Ductility Characterization of U-6Nb and Ta-W Alloys
We have previously evaluated the ductility behaviors of U-6Nb and pure Ta. One important observation was that both alloys have very stable necking ductility independent of test conditions. In contrast, uniform ductility varied significantly depending upon strain rates and temperatures. In general, higher strain rate and lower temperature reduce the uniform ductility. Using literature data, we have developed two dynamic ductility models to predict the ductility behaviors of pure-Ta and water-quenched U-6Nb respectively under extreme conditions. In this study we further evaluate the aging effect on U-6Nb and the W-addition effect on Ta. For U-6Nb, the objective is to determine whether or not the ductility degradation by low-temperature aging mostly measured in quasi-static condition can still be observed under dynamic loading (high strain rate) condition. For Ta-W alloys, the focus is to identify the key control parameter so that the optimal condition of high-strength/high-ductility of Ta-10W can be achieved for certain defense-related applications.
Date:
September 15, 2006
Creator:
Sun, T & Cervantes, O
Object Type:
Article
System:
The UNT Digital Library
Low Cost Fabrication of 2G Wires for AC Applications
Ink-jet printing has been demonstrated as an adaptable technology for printing YBCO filaments using a Metal Organic (MO) YBCO precursor. The technology was demonstrated using AMSC's proprietary metal organic TFA-based YBCO precursor and a commercial piezoelectric print-head on RABiTS templates. Filaments with a width of 100 um and spacing of 200 um were successfully printed, decomposed and processed to YBCO. Critical currents of {approx} 200 A/cm-w were achieved in a series of filaments with a 2 mm width. The single nozzle laboratory printer used in the Phase 1 program is capable of printing {approx} 100 um wide single filaments at a rate of 8-10 cm/sec. The electrical stabilization of filaments with a Ag ink was also evaluated using ink-jet printing. The overall objective of the Phase 1 Project was the evaluation and demonstration of inkjet-printing for depositing YBCO filaments on textured templates (RABiTS, IBAD, ISD, etc. substrates) with properties appropriate for low loss ac conductors. Goals of the Phase 1 program included development of an appropriate precursor ink, demonstration of the printing process, processing and characterization of printed YBCO filaments and evaluation of the process for further development.
Date:
September 15, 2005
Creator:
Kodenkandath, T. & List, F.A., III
Object Type:
Report
System:
The UNT Digital Library
ABSTRACT: Upscaling Fracture Properties in Support of Dual-permeability Simulations
Rainier Mesa (RM) is a tuffaceous, high-elevation plateau on the Nevada Test Site (NTS) that has been subjected to numerous nuclear tests between 1957 and 1992. Unlike other tests on the NTS located within or just above the saturated zone, tests at the RM T-tunnel complex were conducted within a variably saturated sequence of bedded and non-welded vitric and zeolitized tuff units, located approximately 500 m above the regional groundwater flow system. The low permeability and high porosity of the underlying zeolitized tuff units suggest the downward transport of radionuclides released from these tests are minimal through the tuff matrix. However, numerous faults observed to discharge water into tunnel drifts may serve as preferential pathways for radionuclide migration. Data collected from tunnel drifts indicate that faulting within the zeolitized tuff units is sparse with fractal clustering, and that connectivity between adjacent fault clusters is often weak to non-existent. The sparse fault density at RM, in conjunction with the extreme variability in the spatial distribution of faults, poses challenges not readily addressed by existing upscaling methods that upscale fracture properties as equivalent grid tensors. The unique fault statistics at RM has led to the development of a fracture continuum method designed …
Date:
September 15, 2008
Creator:
Parashar, Rishi & Reeves, Donald M.
Object Type:
Article
System:
The UNT Digital Library
Development of Historical Water Table Maps of the 200 West Area of the Hanford Site (1950-1970)
A series of detailed historical water-table maps for the 200-West Area of the Hanford Site was made to aid interpretation of contaminant distribution in the upper aquifer. The contaminants are the result of disposal of large volumes of waste to the ground during Hanford Site operations, which began in 1944 and continued into the mid-1990s. Examination of the contaminant plumes that currently exist on site shows that the groundwater beneath the 200-West Area has deviated from its pre-Hanford west-to-east flow direction during the past 50 years. By using historical water-level measurements from wells around the 200-West Area, it was possible to create water-table contour maps that show probable historic flow directions. These maps are more detailed than previously published water-table maps that encompass the entire Hanford Site.
Date:
September 15, 2006
Creator:
Kinney, Teena M. & McDonald, John P.
Object Type:
Report
System:
The UNT Digital Library
Updating the Nrc Guidance for Human Factors Engineering Reviews.
None
Date:
September 15, 2002
Creator:
O Hara, J. M.; Brown, W. S.; Higgins, J. C.; Persensky, J. J.; Lewis, P. M. & Bongarra, J.
Object Type:
Article
System:
The UNT Digital Library
Concentration of Actinides in Plant Mounds at Safety Test Nuclear Sites in Nevada
Plant mounds or blow-sand mounds are accumulations of soil particles and plant debris around large shrubs and are common features in deserts in the southwestern United States. Believed to be an important factor in their formation, the shrubs create surface roughness that causes wind-suspended particles to be deposited and resist further suspension. Shrub mounds occur in some plant communities on the Nevada Test Site, the Nevada Test and Training Range (NTTR), and Tonopah Test Range (TTR), including areas of surface soil contamination from past nuclear testing. In the 1970s as part of early studies to understand properties of actinides in the environment, the Nevada Applied Ecology Group (NAEG) examined the accumulation of isotopes of Pu, {sup 241}Am, and U in plant mounds at safety test sites. The NAEG studies found concentrations of these contaminants to be greater in shrub mounds than in the surrounding areas of desert pavement. For example, at Project 57 on the NTTR, it was estimated that 15 percent of the radionuclide inventory of the site was associated with shrub mounds, which accounted for 17 percent of the surface area of the site, a ratio of inventory to area of 0.85. At Clean Slate III at the …
Date:
September 15, 2008
Creator:
Shafer, David S. & Gommes, Jenna
Object Type:
Article
System:
The UNT Digital Library
Particle Physics Booklet 2008
None
Date:
September 15, 2008
Creator:
et al., C. Amsler
Object Type:
Report
System:
The UNT Digital Library
Preliminary Safety Evaluation of the Advanced Burner Test Reactor.
Results of a preliminary safety evaluation of the Advanced Burner Test Reactor (ABTR) pre-conceptual design are reported. The ABTR safety design approach is described. Traditional defense-in-depth design features are supplemented with passive safety performance characteristics that include natural circulation emergency decay heat removal and reactor power reduction by inherent reactivity feedbacks in accidents. ABTR safety performance in design-basis and beyond-design-basis accident sequences is estimated based on analyses. Modeling assumptions and input data for safety analyses are presented. Analysis results for simulation of simultaneous loss of coolant pumping power and normal heat rejection are presented and discussed, both for the case with reactor scram and the case without reactor scram. The analysis results indicate that the ABTR pre-conceptual design is capable of undergoing bounding design-basis and beyond-design-basis accidents without fuel cladding failures. The first line of defense for protection of the public against release of radioactivity in accidents remains intact with significant margin. A comparison and evaluation of general safety design criteria for the ABTR conceptual design phase are presented in an appendix. A second appendix presents SASSYS-1 computer code capabilities and modeling enhancements implemented for ABTR analyses.
Date:
September 15, 2006
Creator:
Dunn, F. E.; Fanning, T. H. & Cahalan, J. E.
Object Type:
Report
System:
The UNT Digital Library
Recent Advances in Developing Platinum Monolayer Electrocatalysts for the O2 Reduction Reaction
For Pt, the best single-element catalyst for many reactions, the question of content and loading is exceedingly important because of its price and availability. Using platinum as a fuel-cell catalyst in automotive applications will cause an unquantifiable increase in the demand for this metal. This big obstacle for using fuel cells in electric cars must be solved by decreasing the content of Pt, which is a great challenge of electrocatalysis Over the last several years we inaugurated a new class of electrocatalysts for the oxygen reduction reaction (ORR) based on a monolayer of Pt deposited on metal or alloy carbon-supported nanoparticles. The possibility of decreasing the Pt content in the ORR catalysts down to a monolayer level has a considerable importance because this reaction requires high loadings due to its slow kinetics. The Pt-monolayer approach has several unique features and some of them are: high Pt utilization, enhanced (or decreased) activity, enhanced stability, and direct activity correlations. The synthesis of Pt monolayer (ML) electrocatalysts was facilitated by our new synthesis method which allowed us to deposit a monolayer of Pt on various metals, or alloy nanoparticles [1, 2] for the cathode electrocatalyst. In this synthesis approach Pt is laid down …
Date:
September 15, 2008
Creator:
Vukmirovic, M. B.; Sasaki, K.; Zhou, W. P.; Li, M.; Liu, P.; Wang, J. X. et al.
Object Type:
Article
System:
The UNT Digital Library
Site Environmental Report for 2007 Volume II
The Site Environmental Report for 2007 is an integrated report on the environmental programs at Lawrence Berkeley National Laboratory and satisfies the requirements of DOE Order 231.1A, Environment, Safety, and Health Reporting. Volume II contains individual data results from surveillance and monitoring activities.
Date:
September 15, 2008
Creator:
Lackner, Regina E; Baskin, David; Fox, Robert; Jelinski, John; Pauer, Ron; Thorson, Patrick et al.
Object Type:
Report
System:
The UNT Digital Library
Fluctuations and Gibbs-Thomson Law - the Simple Physics.
Crystals of slightly soluble materials should be subject of relatively weak attachment/detachment fluctuations on their faces so that steps on that faces have low kink density. These steps are parallel to the most close packed lattice rows and form polygons on a crystal surface. The process responsible for implementation of the classical Gibbs-Thomson law (GTL) for the polygonal step (in two dimensions, 2D) is kink exchange between the step corners. For the 3D crystallites, this mechanism includes step exchange. If these mechanisms do not operate because of slow fluctuations the GTL is not applicable. Physics of these processes and conditions for the GTL applicability are discussed on a simple qualitative level.
Date:
September 15, 2006
Creator:
Chernov, A. A.; De Yoreo, J. J. & Rashkovich, L. N.
Object Type:
Article
System:
The UNT Digital Library
Heavy-Ion Irradiation of Thulium(III) Oxide Targets Prepared by Polymer-Assisted Deposition
Thulium(III) oxide (Tm{sub 2}O{sub 3}) targets prepared by the polymer-assisted deposition (PAD) method were irradiated by heavy-ion beams to test the method's feasibility for nuclear science applications. Targets were prepared on silicon nitride backings (thickness of 1000 nm, 344 {micro}g/cm{sup 2}) and were irradiated with an {sup 40}Ar beam at laboratory frame energy of {approx}210 MeV (50 particle nA). The root mean squared (RMS) roughness prior to irradiation is 1.1 nm for a {approx}250 nm ({approx}220 {micro}g/cm{sup 2}) Tm{sub 2}O{sub 3} target, and an RMS roughness of 2.0 nm after irradiation was measured by atomic force microscopy (AFM). Scanning electron microscopy of the irradiated target reveals no significant differences in surface homogeneity when compared to imaging prior to irradiation. Target flaking was not observed from monitoring Rutherford scattered particles as a function of time.
Date:
September 15, 2008
Creator:
Garcia, Mitch A.; Ali, Mazhar N.; Chang, Noel N.; Parsons-Moss, Tashi; Ashby, Paul D.; Gates, Jacklyn M. et al.
Object Type:
Article
System:
The UNT Digital Library
Surface CO2 leakage during the first shallow subsurface CO2release experiment
A new field facility was used to study CO2 migrationprocesses and test techniques to detect and quantify potential CO2leakage from geologic storage sites. For 10 days starting 9 July 2007,and for seven days starting 5 August 2007, 0.1 and 0.3 t CO2 d-1,respectively, were released from a ~;100-m long, sub-water table (~;2.5-mdepth) horizontal well. The spatio-temporal evolution of leakage wasmapped through repeated grid measurements of soil CO2 flux (FCO2). Thesurface leakage onset, approach to steady state, and post-release declinematched model predictions closely. Modeling suggested that minimal CO2was taken up by groundwater through dissolution, and CO2 spread out ontop of the water table. FCO2 spatial patterns were related to well designand soil physical properties. Estimates of total CO2 discharge along withsoil respiration and leakage discharge highlight the influence ofbackground CO2 flux variations on detection of CO2 leakagesignals.
Date:
September 15, 2007
Creator:
Lewicki, J. L.; Oldenburg, C.; Dobeck, L. & Spangler, L.
Object Type:
Article
System:
The UNT Digital Library