States

SOLVENT EXTRACTION FOR URANIUM MOLYBDENUM ALLOY DISSOLUTION FLOWSHEET (open access)

SOLVENT EXTRACTION FOR URANIUM MOLYBDENUM ALLOY DISSOLUTION FLOWSHEET

H-Canyon Engineering requested the Savannah River National Laboratory (SRNL) to perform two solvent extraction experiments using dissolved Super Kukla (SK) material. The SK material is an uranium (U)-molybdenum (Mo) alloy material of 90% U/10% Mo by weight with 20% 235U enrichment. The first series of solvent extraction tests involved a series of batch distribution coefficient measurements with 7.5 vol % tributylphosphate (TBP)/n-paraffin for extraction from 4-5 M nitric acid (HNO{sub 3}), using 4 M HNO{sub 3}-0.02 M ferrous sulfamate (Fe(SO3NH2)2) scrub, 0.01 M HNO3 strip steps with particular emphasis on the distribution of U and Mo in each step. The second set of solvent extraction tests determined whether the 2.5 wt % sodium carbonate (Na2CO3) solvent wash change frequency would need to be modified for the processing of the SK material. The batch distribution coefficient measurements were performed using dissolved SK material diluted to 20 g/L (U + Mo) in 4 M HNO{sub 3} and 5 M HNO{sub 3}. In these experiments, U had a distribution coefficient greater than 2.5 while at least 99% of the nickel (Ni) and greater than 99.9% of the Mo remained in the aqueous phase. After extraction, scrub, and strip steps, the aqueous U product …
Date: June 7, 2007
Creator: Visser, A & Robert Pierce, R
Object Type: Report
System: The UNT Digital Library
Field Demonstration of Carbon Dioxide Miscible Flooding in the Lansing-Kansas City Formation, Central Kansas (open access)

Field Demonstration of Carbon Dioxide Miscible Flooding in the Lansing-Kansas City Formation, Central Kansas

A pilot carbon dioxide miscible flood was initiated in the Lansing Kansas City C formation in the Hall Gurney Field, Russell County, Kansas. The reservoir zone is an oomoldic carbonate located at a depth of about 2900 feet. The pilot consists of one carbon dioxide injection well and three production wells. Continuous carbon dioxide injection began on December 2, 2003. By the end of June 2005, 16.19 MM lb of carbon dioxide were injected into the pilot area. Injection was converted to water on June 21, 2005 to reduce operating costs to a breakeven level with the expectation that sufficient carbon dioxide has been injected to displace the oil bank to the production wells by water injection. By December 31, 2006, 79,072 bbls of water were injected into CO2 I-1 and 3,923 bbl of oil were produced from the pilot. Water injection rates into CO2 I-1, CO2 No.10 and CO2 No.18 were stabilized during this period. Oil production rates increased from 4.7 B/D to 5.5 to 6 B/D confirming the arrival of an oil bank at CO2 No.12. Production from wells to the northwest of the pilot region indicates that oil displaced from carbon dioxide injection was produced from Colliver …
Date: March 7, 2007
Creator: Byrnes, Alan; Willhite, G. Paul; Green, Don; Dubois, Martin; Pancake, Richard; Carr, Timothy et al.
Object Type: Report
System: The UNT Digital Library
Lattice QCD Thermodynamcis : P4 Action for new beta and MILC Nt=6 (open access)

Lattice QCD Thermodynamcis : P4 Action for new beta and MILC Nt=6

These results are from the continuing Lattice Quantum Chromodynamics runs on BG/L. We show analyzed thermodynamics results for 6-10k trajectories ({beta} dependent), of the 32{sup 3}{chi}8 runs with the p4rhmc v2.0 QMP{_}MPI.X (semi-optimized p4 code using qmp over mpi). These jobs had a number of omitted trajectories, due to zero size and over-sized data files. For this interim report these errors were removed from the output to save space. The results also include the output of a new ''histogram.perl'' script, used to plot the gauge action < S{sub g} >= 10*(1- < plaq >)-(1- < rect >) for three values of {beta}=3.51, 3.54, 3.57. This output will be used to determine the new {beta} values that will be run to define the critical temperature. We also show a preliminary analysis on the first 5,000 trajectories of the 32{sup 3}{chi}6 runs for the milc code, using the new su3{_}rhmc{_}susc{_}eos.3g1f.qmp-bgl2 faster RHMC algorithm.
Date: May 7, 2007
Creator: Soltz, R.; Vranas, P. & Gupta, R.
Object Type: Report
System: The UNT Digital Library
AGING PERFORMANCE OF VITON GLT O-RINGS IN RADIOACTIVE MATERIAL PACKAGES (open access)

AGING PERFORMANCE OF VITON GLT O-RINGS IN RADIOACTIVE MATERIAL PACKAGES

Radioactive material packages used for transportation of plutonium-bearing materials often contain multiple O-ring seals for containment. Packages such as the Model 9975 are also being used for interim storage of Pu-bearing materials at the Savannah River Site (SRS). One of the seal materials used in such packages is Viton{reg_sign} GLT fluoroelastomer. The aging behavior of containment vessel O-rings based on Viton{reg_sign} GLT at long-term containment term storage conditions is being characterized to assess its performance in such applications. This paper summarizes the program and test results to date.
Date: May 7, 2007
Creator: Skidmore, E; Kerry Dunn, K; Elizabeth Hoffman, E; Elise Fox, E & Kathryn Counts, K
Object Type: Article
System: The UNT Digital Library
Electromagnetic Interference from the ILC Beams (open access)

Electromagnetic Interference from the ILC Beams

Electromagnetic interference is an emerging problem of the future. This investigation analyzed the data collected from airborne radiation waves that caused electronic devices to fail. This investigation was set up at SLAC in End Station A and the data collected from the electromagnetic waves were received from antennas. In order to calibrate the antennas it required a signal generator to transmit the signals to the antenna and a digital oscilloscope to receive the radiation waves from the other antenna. The signal generator that was used was only able to generate signals between 1 and 1.45 GHz; therefore, the calibrations were not able to be completed. Instead, excel was used to create a curve fitting for the attenuation factors that were already factory calibrated. The function from the curve fitting was then used to extend the calibrations on the biconical and yagi antennas. A fast Fourier Transform was then ran in Matlab on the radiation waves received by the oscilloscope; in addition, the attenuation factors were calculated into the program to show the actual amplitudes of these radiation waves. For future research, the antennas will be manually calibrated and the results will be reanalyzed.
Date: November 7, 2007
Creator: Brown, LaVonda N. & /SLAC, /Norfolk State U.
Object Type: Article
System: The UNT Digital Library
Superconducting Materials Testing with a High-Q Copper RF Cavity (open access)

Superconducting Materials Testing with a High-Q Copper RF Cavity

Superconducting RF is of increasing importance in particle accelerators. We have developed a resonant cavity with high quality factor and an interchangeable wall for testing of superconducting materials. A compact TE01 mode launcher attached to the coupling iris selectively excites the azimuthally symmetric cavity mode, which allows a gap at the detachable wall and is free of surface electric fields that could cause field emission, multipactor, and RF breakdown. The shape of the cavity is tailored to focus magnetic field on the test sample. We describe cryogenic experiments conducted with this cavity. An initial experiment with copper benchmarked our apparatus. This was followed by tests with Nb and MgB2. In addition to characterizing the onset of superconductivity with temperature, our cavity can be resonated with a high power klystron to determine the surface magnetic field level sustainable by the material in the superconducting state. A feedback code is used to make the low level RF drive track the resonant frequency.
Date: November 7, 2007
Creator: Tantawi, S. G.; Dolgashev, V.; Bowden, G.; Lewandowski, J.; Nantista, C. D.; Canabal, A. et al.
Object Type: Article
System: The UNT Digital Library
Structure of ZnO Nanorods using X-ray Diffraction (open access)

Structure of ZnO Nanorods using X-ray Diffraction

Many properties of zinc oxide, including wide bandgap semiconductivity, photoconductivity, and chemical sensing, make it a very promising material for areas such as optoelectronics and sensors. This research involves analysis of the formation, or nucleation, of zinc oxide by electrochemical deposition in order to gain a better understanding of the effect of different controlled parameters on the subsequently formed nanostructures. Electrochemical deposition involves the application of a potential to an electrolytic solution containing the species of interest, which causes the ions within to precipitate on one of the electrodes. While there are other ways of forming zinc oxide, this particular process is done at relatively low temperatures, and with the high amount of x-ray flux available at SSRL it is possible to observe such nucleation in situ. Additionally, several parameters can be controlled using the x-ray synchrotron; the concentration of Zn{sup 2+} and the potential applied were controlled during this project. The research involved both gathering the X-ray diffraction data on SSRL beamline 11-3, and analyzing it using fit2d, Origin 6.0 and Microsoft Excel. A time series showed that both the in-plane and out-of-plane components of the ZnO nanorods grew steadily at approximately the same rate throughout deposition. Additionally, analysis …
Date: November 7, 2007
Creator: Howdyshell, Marci & /SLAC, /Albion Coll.
Object Type: Article
System: The UNT Digital Library
Scalability of the natural convection shutdown heat removal test facility (NSTF) data to VHTR/NGNP RCCS designs. (open access)

Scalability of the natural convection shutdown heat removal test facility (NSTF) data to VHTR/NGNP RCCS designs.

Passive safety in the Very High Temperature Reactor (VHTR) is strongly dependent on the thermal performance of the Reactor Cavity Cooling System (RCCS). Scaled experiments performed in the Natural Shutdown Test Facility (NSTF) are to provide data for assessing and/or improving computer code models for RCCS phenomena. Design studies and safety analyses that are to support licensing of the VHTR will rely on these models to achieve a high degree of certainty in predicted design heat removal rate. To guide in the selection and development of an appropriate set of experiments a scaling analysis has been performed for the air-cooled RCCS option. The goals were to (1) determine the phenomena that dominate the behavior of the RCCS, (2) determine the general conditions that must be met so that these phenomena and their relative importance are preserved in the experiments, (3) identify constraints specific to the NSTF that potentially might prevent exact similitude, and (4) then to indicate how the experiments can be scaled to prevent distortions in the phenomena of interest. The phenomena identified as important to RCCS operation were also the subject of a recent PIRT study. That work and the present work collectively indicate that the main phenomena …
Date: August 7, 2007
Creator: Vilim, R .B. & Feldman, E. E.
Object Type: Report
System: The UNT Digital Library
Re-Analysis of Hydroacoustic Fish-Passage Data from Bonneville Dam after Spill-Discharge Corrections (open access)

Re-Analysis of Hydroacoustic Fish-Passage Data from Bonneville Dam after Spill-Discharge Corrections

The U.S. Army Corps of Engineers - Portland District asked Pacific Northwest National Laboratory to re-analyze four years of fixed-aspect hydroacoustic data after the District made adjustments to spill discharge estimates. In this report, we present new estimates of all major fish-passage metrics for study years 2000, 2001, 2002, and 2004, as well as estimates for 2005. This study supports the Portland District and its effort to maximize survival of juvenile salmon passing Bonneville Dam. Major passage routes through Bonneville Dam include 10 turbines and a sluiceway at Powerhouse 1 (B1), an 18-bay spillway, and eight turbines at Powerhouse 2 (B2) and a sluiceway including the B2 Corner Collector. The original reports and all associated results, discussion, and conclusions for non flow-related metrics remain valid and useful, but effectiveness measures for study years 2000, 2001, 2002, and 2004 as reported in previous reports by Ploskey et al. should be superseded with the new estimates reported here. The fish-passage metrics that changed the most were related to effectiveness. Re-analysis produced spill effectiveness estimates that ranged from 12% to 21% higher than previous estimates in spring and 16.7% to 27.5% higher in summer, but the mean spill effectiveness over all years was …
Date: June 7, 2007
Creator: Ploskey, Gene R.; Kim, Jina; Weiland, Mark A.; Hughes, James S. & Fischer, Eric S.
Object Type: Report
System: The UNT Digital Library
Final Scientific/Technical Report to the U.S. Department of Energy on NOVA's Einstein's Big Idea (Project title: E-mc2, A Two-Hour Television Program on NOVA) (open access)

Final Scientific/Technical Report to the U.S. Department of Energy on NOVA's Einstein's Big Idea (Project title: E-mc2, A Two-Hour Television Program on NOVA)

Executive Summary A woman in the early 1700s who became one of Europe’s leading interpreters of mathematics and a poor bookbinder who became one of the giants of nineteenth-century science are just two of the pioneers whose stories NOVA explored in Einstein’s Big Idea. This two-hour documentary premiered on PBS in October 2005 and is based on the best-selling book by David Bodanis, E=mc2: A Biography of the World’s Most Famous Equation. The film and book chronicle the scientific challenges and discoveries leading up to Einstein’s startling conclusion that mass and energy are one, related by the formula E = mc2.
Date: May 7, 2007
Creator: Simpson, Susanne
Object Type: Report
System: The UNT Digital Library
Organizing the Extremely Large LSST Database forReal-Time Astronomical Processing (open access)

Organizing the Extremely Large LSST Database forReal-Time Astronomical Processing

The Large Synoptic Survey Telescope (LSST) will catalog billions of astronomical objects and trillions of sources, all of which will be stored and managed by a database management system. One of the main challenges is real-time alert generation. To generate alerts, up to 100K new difference detections have to be cross-correlated with the huge historical catalogs, and then further processed to prune false alerts. This paper explains the challenges, the implementation of the LSST Association Pipeline and the database organization strategies we are planning to use to meet the real-time requirements, including data partitioning, parallelization, and pre-loading.
Date: November 7, 2007
Creator: Becla, Jacek; Lim, Kian-Tat; Monkewitz, Serge; Nieto-Santisteban, Maria & Thakar, Ani
Object Type: Article
System: The UNT Digital Library
Bunch by Bunch Profiling with a Rotating X-ray Mask (open access)

Bunch by Bunch Profiling with a Rotating X-ray Mask

It is desirable to monitor the cross sections of each positron bunch in the Low Energy Ring (LER) storage rings of the Positron Electron Project II (PEP-II) located at the Stanford Linear Accelerator Center. One method is to pass the x-rays given off by each bunch through a scintillator, thereby studying a visible image. A rotating x-ray mask with three slots scans the beam image in three different orientations, allowing us to mechanically collect data to characterize and profile each image. Progress was made in designing the x-ray mask, researching and procuring parts, as well as advancing project plans. However, due to time constraints and difficulties in procuring special parts, the full system was not completed. A simpler setup was built to test the hardware as well as the feasibility of characterizing a circular image with a rotating mask. A blinking green light emitting diode (LED) simulated a single positron bunch stored in the LER ring. The selected hardware handled this simulation setup well and produced data that led to a reasonable estimation of the LED image diameter.
Date: November 7, 2007
Creator: Lee, Christopher J. & /UC, San Diego
Object Type: Article
System: The UNT Digital Library
Final Report: 17th international Symposium on Plant Lipids (open access)

Final Report: 17th international Symposium on Plant Lipids

This meeting covered several emerging areas in the plant lipid field such as the biosynthesis of cuticle components, interorganelle lipid trafficking, the regulation of lipid homeostasis, and the utilization of algal models. Stimulating new insights were provided not only based on research reports based on plant models, but also due to several excellent talks by experts from the yeast field.
Date: March 7, 2007
Creator: Benning, Christoph
Object Type: Text
System: The UNT Digital Library
Measurements of High-Field THz Induced Photocurrents in Semiconductors (open access)

Measurements of High-Field THz Induced Photocurrents in Semiconductors

THz pulses have provided a useful tool for probing, with time resolution, the free carriers in a system. The development of methods to produce intense THz radiation has been slow since spectroscopists and condensed matter physicists first began probing materials with THz pulses. We have developed a method for producing intense ultra-short THz pulses, which have full width half maximum of 300 fs - approximately a half cycle of THz radiation. These intense half cycle pulses (HCPs) allow us to use THz radiation not only as a probe of the free carriers in a system but also as a source of excitation to alter a system in some way. In particular, HPCs perturb free carriers considerably in short time scales but show minimal effect to individual free carriers over long time. By exposing the semiconductor indium antimonide (InSb) to our intense THz HCP radiation, we have observed non-linear optical effects which suggest the generation of new free carriers by below band-gap THz photons. This generation of free carriers appears to be caused by an avalanche multiplication process, which should amplify the number of free carriers already in the system and then induce a current in the timescale of our THz …
Date: November 7, 2007
Creator: Wiczer, Michael
Object Type: Article
System: The UNT Digital Library
Monolithic Active Pixel Matrix with Binary Counters in an SOI Process (open access)

Monolithic Active Pixel Matrix with Binary Counters in an SOI Process

The design of a Prototype monolithic active pixel matrix, designed in a 0.15 {micro}m CMOS SOI Process, is presented. The process allowed connection between the electronics and the silicon volume under the layer of buried oxide (BOX). The small size vias traversing through the BOX and implantation of small p-type islands in the n-type bulk result in a monolithic imager. During the acquisition time, all pixels register individual radiation events incrementing the counters. The counting rate is up to 1 MHz per pixel. The contents of counters are shifted out during the readout phase. The designed prototype is an array of 64 x 64 pixels and the pixel size is 26 x 26 {micro}m{sup 2}.
Date: June 7, 2007
Creator: Duptuch, G. & Yarema, R.
Object Type: Article
System: The UNT Digital Library
DATA QUALITY OBJECTIVES SUMMARY REPORT FOR THE 105K EAST BASIN ION EXCHANGE COLUMN MONOLITH (open access)

DATA QUALITY OBJECTIVES SUMMARY REPORT FOR THE 105K EAST BASIN ION EXCHANGE COLUMN MONOLITH

The 105-K East (KE) Basin Ion Exchange Column (IXC) cells, lead caves, and the surrounding vault are to be removed as necessary components in implementing ''Hanford Federal Facility Agreement and Consert Order'' (Ecology et al. 2003) milestone M-034-32 (Complete Removal of the K East Basin Structure). The IXCs consist of six units located in the KE Basin, three in operating positions in cells and three stored in a lead cave. Methods to remove the IXCs from the KE Basin were evaluated in KBC-28343, ''Disposal of K East Basin Ion Exchange Column Evaluation''. The method selected for removal was grouting of the six IXCs into a single monolith for disposal at the Environmental Restoration Disposal Facility (ERDF). Grout will be added to the IXC cells, IXC lead caves containing spent IXCs, and in the spaces between to immobilize the contaminants, provide self-shielding, minimize void space, and provide a structurally stable waste form. The waste to be offered for disposal is the encapsulated monolith defined by the exterior surfaces of the vault and the lower surface of the underlying slab. This document presents a summary of the data quality objective (DQO) process establishing the decisions and data required to support decision-making activities …
Date: February 7, 2007
Creator: JOCHEN, R.M.
Object Type: Report
System: The UNT Digital Library
Introducing Defects in Photonic Band-Gap (PBG) Crystals (open access)

Introducing Defects in Photonic Band-Gap (PBG) Crystals

Photonic Band-Gap (PBG) fibers are a periodic array of optical materials arranged in a lattice called a photonic crystal. The use of PBG fibers for particle acceleration is being studied by the Advanced Accelerator Research Department (AARD) at SLAC. By introducing defects in such fibers, e.g. removing one or more capillaries from a hexagonal lattice, spatially confined modes suitable for particle acceleration may be created. The AARD has acquired several test samples of PBG fiber arrays with varying refractive index, capillary size, and length from an external vendor for testing. The PBGs were inspected with a microscope and characteristics of the capillaries including radii, spacing, and errors in construction were determined. Transmission tests were performed on these samples using a broad-range spectrophotometer. In addition, detailed E-field simulations of different PBG configurations were done using the CUDOS and RSOFT codes. Several accelerating modes for different configurations were found and studied in detail.
Date: November 7, 2007
Creator: Johnson, Elliott C. & /SLAC, /North Dakota State U.
Object Type: Article
System: The UNT Digital Library
Lethality Effects of a High-Power Solid-State Laser (open access)

Lethality Effects of a High-Power Solid-State Laser

We study the material interactions of a 25-kW solid-state laser, in experiments characterized by relatively large spot size sizes ({approx}3 cm) and the presence of airflow. The targets are 1-cm slabs of iron or aluminum. In the experiments with iron, we show that combustion plays an important role in heating the material. In the experiments with aluminum, there is a narrow range of intensities within which the material interactions vary from no melting at all to complete melt-through. A paint layer serves to increase the absorption. We explain these effects and incorporate them into a comprehensive computational model.
Date: March 7, 2007
Creator: Boley, C.; Fochs, S. & Rubenchik, A.
Object Type: Article
System: The UNT Digital Library
Calculating IP Tuning Knobs for the PEP II High Energy Ring using Singular Value Decomposition, Response Matrices and an Adapted Moore Penrose Method (open access)

Calculating IP Tuning Knobs for the PEP II High Energy Ring using Singular Value Decomposition, Response Matrices and an Adapted Moore Penrose Method

The PEP II lattices are unique in their detector solenoid field compensation scheme by utilizing a set of skew quadrupoles in the IR region and the adjacent arcs left and right of the IP. Additionally, the design orbit through this region is nonzero. This combined with the strong local coupling wave makes it very difficult to calculate IP tuning knobs which are orthogonal and closed. The usual approach results either in non-closure, not being orthogonal or the change in magnet strength being too big. To find a solution, the set of tuning quads had to be extended which resulted having more degrees of freedom than constraints. To find the optimal set of quadrupoles which creates a linear, orthogonal and closed knob and simultaneously minimizing the changes in magnet strength, the method using Singular Value Decomposition, Response Matrices and an Adapted Moore Penrose method had to be extended. The results of these simulations are discussed below and the results of first implementation in the machine are shown.
Date: November 7, 2007
Creator: Wittmer, W.
Object Type: Article
System: The UNT Digital Library
Strontium Isotopic Composition of Paleozoic Carbonate Rocks in the Nevada Test Site Vicinity, Clark, Lincoln, and Nye Counties, Nevada and Inyo County, California. (open access)

Strontium Isotopic Composition of Paleozoic Carbonate Rocks in the Nevada Test Site Vicinity, Clark, Lincoln, and Nye Counties, Nevada and Inyo County, California.

Ground water moving through permeable Paleozoic carbonate rocks represents the most likely pathway for migration of radioactive contaminants from nuclear weapons testing at the Nevada Test Site, Nye County, Nevada. The strontium isotopic composition (87Sr/86Sr) of ground water offers a useful means of testing hydrochemical models of regional flow involving advection and reaction. However, reaction models require knowledge of 87Sr/86Sr data for carbonate rock in the Nevada Test Site vicinity, which is scarce. To fill this data gap, samples of core or cuttings were selected from 22 boreholes at depth intervals from which water samples had been obtained previously around the Nevada Test Site at Yucca Flat, Frenchman Flat, Rainier Mesa, and Mercury Valley. Dilute acid leachates of these samples were analyzed for a suite of major- and trace-element concentrations (MgO, CaO, SiO2, Al2O3, MnO, Rb, Sr, Th, and U) as well as for 87Sr/86Sr. Also presented are unpublished analyses of 114 Paleozoic carbonate samples from outcrops, road cuts, or underground sites in the Funeral Mountains, Bare Mountain, Striped Hills, Specter Range, Spring Mountains, and ranges east of the Nevada Test Site measured in the early 1990's. These data originally were collected to evaluate the potential for economic mineral deposition …
Date: August 7, 2007
Creator: Paces, James B.; Peterman, Zell E.; Futa, Kiyoto; Oliver, Thomas A. & Marshall., and Brian D.
Object Type: Report
System: The UNT Digital Library
Laboratory Assessment of Potential Impacts to Dungeness Crabs from Disposal of Dredged Material from the Columbia River (open access)

Laboratory Assessment of Potential Impacts to Dungeness Crabs from Disposal of Dredged Material from the Columbia River

Dredging of the Columbia River navigation channel has raised concerns about dredging-related impacts on Dungeness crabs (Cancer magister) in the estuary, mouth of the estuary, and nearshore ocean areas adjacent to the Columbia River. The Portland District, U.S. Army Corps of Engineers engaged the Marine Sciences Laboratory (MSL) of the U.S. Department of Energy’s Pacific Northwest National Laboratory to review the state of knowledge and conduct studies concerning impacts on Dungeness crabs resulting from disposal during the Columbia River Channel Improvement Project and annual maintenance dredging in the mouth of the Columbia River. The present study concerns potential effects on Dungeness crabs from dredged material disposal specific to the mouth of the Columbia River.
Date: May 7, 2007
Creator: Vavrinec, John; Pearson, Walter H.; Kohn, Nancy P.; Skalski, J. R.; Lee, Cheegwan; Hall, Kathleen D. et al.
Object Type: Report
System: The UNT Digital Library
NEST-GENERATION TCAP HYDROGEN ISOTOPE SEPARATION PROCESS (open access)

NEST-GENERATION TCAP HYDROGEN ISOTOPE SEPARATION PROCESS

A thermal cycling absorption process (TCAP) for hydrogen isotope separation has been in operation at Savannah River Site since 1994. The process uses a hot/cold nitrogen system to cycle the temperature of the separation column. The hot/cold nitrogen system requires the use of large compressors, heat exchanges, valves and piping that is bulky and maintenance intensive. A new compact thermal cycling (CTC) design has recently been developed. This new design uses liquid nitrogen tubes and electric heaters to heat and cool the column directly so that the bulky hot/cold nitrogen system can be eliminated. This CTC design is simple and is easy to implement, and will be the next generation TCAP system at SRS. A twelve-meter column has been fabricated and installed in the laboratory to demonstrate its performance. The design of the system and its test results to date is discussed.
Date: August 7, 2007
Creator: Heung, L; Henry Sessions, H; Anita Poore, A; William Jacobs, W & Christopher Williams, C
Object Type: Article
System: The UNT Digital Library
Plasma Physics Junior Faculty Development Award (open access)

Plasma Physics Junior Faculty Development Award

None
Date: June 7, 2007
Creator: Lin, Zhihong
Object Type: Report
System: The UNT Digital Library
Minimal Direct Gauge Mediation (open access)

Minimal Direct Gauge Mediation

We propose a simple model of gauge mediation with a small gravitino mass, m{sub 3/2} < O(10) eV, where supersymmetry is broken by a strong dynamics at O(10) TeV.
Date: November 7, 2007
Creator: Ibe, Masahiro & Kitano, Ryuichiro
Object Type: Report
System: The UNT Digital Library