Serial/Series Title
Fiscal Year 2004
4
ADEPT Program
2
ARM Facilities Newsletter
2
Downhole Power Generation and Wireless Communications for Intelligent Completions Applications, Quarterly Report
2
Fiscal Year 1996
2
Winter Fuels Report
2
Active Cathodes for Super-High Power Density Solid Oxide Fuel Cells Through Space Charge Effects Quarterly Report
1
CO2 Capture by Absorption With Potassium Carbonate Quarterly Report
1
Chemical Processing Department Monthly Report
1
Development of Continuous Solvent Extraction Processes for Coal Derived Carbon Products Quarterly Report
1
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Progress and future plans for MPC and A at Chelyabinsk-70
This paper describes that portion of the Nuclear Materials Protection, Control, and Accounting (MPC and A) program that is directed specifically to the needs of the All Russian Scientific Research Institute of Technical Physics (VNIITF), also called Chelyabinsk-70. Chelyabinsk-70 is located in the Ural Mountains, approximately 2000 km east of Moscow and 100 km south of Ekaterinburg. The MPC and A work that has been completed, is underway and planned at the facility will be described. During the first two years of the VNIITF project, emphasis was on the Pulse Research Reactor Facility (PRR), which contains one metal and two liquid pulse reactors and associated nuclear material storage rooms and a control center. A commissioning of the PRR was held in May of 1998. With the completion of the MPC and A work in the PRR, new physical protection work is focusing on other areas. VNIITF-wide physical protection initiatives underway include access control and computerized badging systems, and a central MPC and A control system. Measured physical inventory taking is a high priority for the VNIITF Project Team. A VNIITF-wide computerized accounting system is also being developed for the large and diverse inventory of nuclear material subject to MPC and …
Date:
July 8, 1999
Creator:
Apt, K.; Blasy, J.; Bukin, D.; Cahalane, P.; Churikov, Y.; Curtis, D. et al.
Object Type:
Article
System:
The UNT Digital Library
ICF quarterly report October-December 1998 volume 8, number 1
This issue of the ICF Quarterly Report focuses on the final section of the 192-arm, 1.8-MJ National Ignition Facility (NIF). We describe both technological advances necessary for optimal utilization of the delivered energy and the hohlraum physics resulting from extremely high energy densities. Two articles belong to the first category. The conversion of infrared light to ultraviolet occurs at the tripler in the NIF's Final Optics Assembly. It is then necessary to separate any unconverted (first- and second-harmonic) light from the tripled-frequency light passed to the target. Large-Aperture Color-Separation Gratings for Diverting Unconverted Light Away from the NIF Target describes the design and fabrication of novel diffraction gratings that fulfill this function. In both direct- and indirect-drive ICF, the symmetry of the capsule as it compresses is crucial. The NIF will have 48 clusters of four beams incident on targets. Optimization of Beam Angles for the National Ignition Facility (p. 15) presents the rationale used to assign beam angles for cylindrical indirect drive while still allowing direct-drive and tetrahedral indirect-drive experiments to be performed.
Date:
September 8, 1998
Creator:
Feit, M
Object Type:
Report
System:
The UNT Digital Library
Characterizing the altered zone at Yucca Mountain: The beginning of a testing strategy
The concept of a disturbed zone surrounding the mined openings of a potential geologic repository for high-level radioactive waste was introduced by the US Nuclear Regulatory Commission (NRC) as a region to be excluded for determining groundwater travel time to the accessible environment, but to be included for determining the impact of underground construction and radioactive decay heat on groundwater movement and radionuclide transport for total system performance analysis. This paper explores both the regulatory and technical necessity for characterizing and modeling a larger region -- the altered zone -- within which the temperature is increased significantly by heat from the high-level waste. Particular attention is given to addressing the effects of heterogeneity on groundwater flux and travel time, showing how these effects might be modeled simply on a macroscopic scale, and outlining its parameters. The effect of uncertainty in the parameter values on the performance of a potential repository can then be easily handled by probabilistic analysis.
Date:
January 8, 1992
Creator:
Chesnut, D.A.
Object Type:
Article
System:
The UNT Digital Library
Development of a catalyst for conversion of syngas-derived materials to isobutylene. Quarterly report No. 7, October 1, 1992--December 31, 1992
The main goal of this contract is to develop a catalyst and technology that will produce iC{sub 4}= directly from coal-derived syngas and that is capable of utilizing a lower (0.5 to 1.0) H{sub 2}:CO ratio. The research will identify and optimize the key catalyst and process characteristics that give improved performance for CO conversion by a non-Fischer-Tropsch process. This report, which is the seventh quarterly report covers the testing of various ZrO{sub 2}-based catalyst systems designed to examine the effects of catalyst preparation and process variables, especially low calcination temperature and mild reaction conditions (low temperatures, low pressure and low space velocity). Testing of solvent-extracted sol-gel ZrO{sub 2} catalysts indicate a decrease in isobutene yield. Lowering the reaction temperature, pressure and space velocity resulted in a small improvement in isobutene yield. Three extended runs demonstrated reasonable catalyst stability. In view of the generally poor isobutene yields, the emphasis in this project will shift to isoalcohol production.
Date:
September 8, 1993
Creator:
Gajda, G.J.
Object Type:
Report
System:
The UNT Digital Library
Effects of inflow on NuMI groundwater concentrations
Recent discussions of the NuMI groundwater problem have been concerned with the effect of inflow of water into the tunnel on the overall groundwater concentration. The purpose of this note is to document calculations of these effects using simple mathematical models. These results can, then, be compared with the results obtained using more elaborate methods such as computer modeling techniques. At Fermilab, a concentration model has been developed to address groundwater activation concerns. While this model has evolved to some degree over time, the main features have remained stable.
Date:
September 8, 1999
Creator:
Cossairt, J. Donald
Object Type:
Report
System:
The UNT Digital Library
Beam tests of the 12 MHz RFQ RIB injector for ATLAS.
In recent tests without beam, the Argonne 12 MHz split-coaxial radio-frequency quadruple (RFQ) achieved a cw intervane voltage of more than 100 kV, the design operating voltage for the device. This voltage is sufficient for the RFQ to function as the first stage of a RIB injector for the Argonne Tandem Linear Accelerator System (ATLAS). Previously reported beam dynamics calculations for the structure predict longitudinal emittance growth of only a few keV{center_dot}ns for beams of mass 132 and above with transverse emittance of 0.27 {pi} mm{center_dot}mrad (normalized). Such beam quality is not typical of RFQ devices. The work reported here is preparation for tests with beams of mass up to 132. Beam diagnostic stations are being developed to measure the energy gain and beam quality of heavy ions accelerated by the RFQ using the Dynamitron accelerator facility at the ANL Physics Division as the injector. Beam diagnostic development includes provisions for performing the measurements with both a Si charged-particle detector and an electrostatic energy spectrometer system.
Date:
February 8, 1999
Creator:
Kaye, R. A.
Object Type:
Article
System:
The UNT Digital Library
Medical applications of ultra-short pulse lasers
The medical applications for ultra short pulse lasers (USPLs) and their associated commercial potential are reviewed. Short pulse lasers offer the surgeon the possibility of precision cutting or disruption of tissue with virtually no thermal or mechanical damage to the surrounding areas. Therefore the USPL offers potential improvement to numerous existing medical procedures. Secondly, when USPLs are combined with advanced tissue diagnostics, there are possibilities for tissue-selective precision ablation that may allow for new surgeries that cannot at present be performed. Here we briefly review the advantages of short pulse lasers, examine the potential markets both from an investment community perspective, and from the view. of the technology provider. Finally nominal performance and cost requirements for the lasers, delivery systems and diagnostics and the present state of development will be addressed.
Date:
June 8, 1999
Creator:
Kim, B. M. & Marion, J. E.
Object Type:
Article
System:
The UNT Digital Library
The BTeV Trigger System
BTeV is a dedicated beauty and charm experiment proposed for the Fer- milab Tevatron. The broad physics program envisaged for BTeV requires a trigger that is efficient for a wide variety of heavy-quark decays, includ- ing those to all-hadronic final states. To achieve this, we plan to trigger on evidence of detached vertices at the very first trigger level, taking ad- vantage of fast-readout pixel detectors to facilitate fast pattern recognition. Simulations show that 100-to-1 rejection of light-quark background events can be achieved at Level 1 using specialized trackfinding hardware, and that an additional factor of 10 to 100 in data reduction can be achieved using general-purpose-processor farms at Levels 2 and 3. This is adequate to allow data-taking at luminosities in excess of 2 x 10<sup>32</sup> cm<sup>-2</sup>s<sup>-1</sup>.
Date:
October 8, 1999
Creator:
Kaplan, Daniel M.
Object Type:
Article
System:
The UNT Digital Library
The Role of Strong Coupling in Z-Pinch-Driven Approaches to High Yield Inertial Confinement Fusion
Peak x-ray powers as high as 280 {+-} 40 TW have been generated from the implosion of tungsten wire arrays on the Z Accelerator at Sandia National Laboratories. The high x-ray powers radiated by these z-pinches provide an attractive new driver option for high yield inertial confinement fusion (ICF). The high x-ray powers appear to be a result of using a large number of wires in the array which decreases the perturbation seed to the magnetic Rayleigh-Taylor (MRT) instability and diminishes other 3-D effects. Simulations to confirm this hypothesis require a 3-D MHD code capability, and associated databases, to follow the evolution of the wires from cold solid through melt, vaporization, ionization, and finally to dense imploded plasma. Strong coupling plays a role in this process, the importance of which depends on the wire material and the current time history of the pulsed power driver. Strong coupling regimes are involved in the plasmas in the convolute and transmission line of the powerflow system. Strong coupling can also play a role in the physics of the z-pinch-driven high yield ICF target. Finally, strong coupling can occur in certain z-pinch-driven application experiments.
Date:
November 8, 1999
Creator:
MEHLHORN,THOMAS A.; DESJARLAIS,MICHAEL P.; HAILL,THOMAS A.; LASH,JOEL S.; ROSENTHAL,STEPHEN E.; SLUTZ,STEPHEN A. et al.
Object Type:
Article
System:
The UNT Digital Library
Impedance considerations for the Intense Pulse Neutron Source (IPNS) Rapid Cycling Synchrotron (RCS).
The use of Second Harmonic (SH) rf is being investigated to increase the Rapid Cycling Synchrotron (RCS) current limit. Hofmann-Pedersen distributions are employed to provide analytical guidance. The SH phase {theta}, is optimized using a numerical analysis to maximize transmission and minimize instabilities. The effect of the RCS stainless steel liner on the impedance of the machine is also discussed.
Date:
September 8, 1999
Creator:
Brumwell, F. R.; Dooling, J. C. & McMichael, G. E.
Object Type:
Article
System:
The UNT Digital Library
Test documentation to convert TWRS baseline data for RDD-100 upgrades
This document describes the test documentation required for converting between different versions of the RDD-100 software application. The area of focus is the successful conversion of the master data set between different versions of the database tool and their corresponding data structures.
Date:
April 8, 1997
Creator:
Gneiting, B.C.
Object Type:
Report
System:
The UNT Digital Library
Non-linear Mode Coupling and Saw-Tooth Instability
Dynamics of the longitudinal relaxation oscillations of a single bunch above the threshold of microwave instability is discussed.
Date:
September 8, 1999
Creator:
Heifets, Samuel A
Object Type:
Report
System:
The UNT Digital Library
Online monitoring in the upcoming Fermilab Tevatron Run II
We describe the online event monitoring systems using ROOT [1] for the CDF and D0 collaborations in the upcoming Fermilab Tevatron runII. The CDF and D0 experiments consist of many detector subsystems and will run in a high rate large bandwidth data transfer environment. In the experiments, it is crucial to monitor the performance of each subsystem and the integrity of the data, in real time with minimal interruption. ROOT is used as the main analysis tool for the monitoring systems and its GUI is used to browse the results via socket, allowing multiple GUI client connections.
Date:
September 8, 1999
Creator:
Canal, P.; Kowalkowski, J.; Maeshima, K.; Yu, J.; Wenzel, H.; Snow, J. et al.
Object Type:
Article
System:
The UNT Digital Library
New perspectives on the cancer risks of trichloroethylene, its metabolites, and chlorination by-products
Scientific developments in the 1990`s have important implications for the assessment of cancer risks posed by exposures to trichloroethylene (TCE). These new developments include: epidemiological studies; experimental studies of TCE carcinogenicity, metabolism and metabolite carcinogenicity; applications of new physiologically based pharmacokinetic (PBPK) models for TCE; and new pharmacodynamic data obtained for TCE and its rhetabolites. Following a review of previous assessments of TCE carcinogenicity, each of these new sets of developments is summarized. The new epidemiological data do not provide evidence of TCE carcinogenicity in humans, and the new pharmacodynamic data support the hypothesis that TCE carcinogenicity is caused by TCE-induced cytotoxicity. Based on this information, PBPK-based estimates for likely no-adverse effect levels (NOAELs) for human exposures to TCE are calculated to be 16 ppb for TCE in air respired 24 hr/day, and 210 ppb for TCE in drinking water. Cancer risks of zero are predicted for TCE exposures below these calculated NOAELs. For comparison, hypothetical cancer risks posed by lifetime ingestive and multiroute household exposures to TCE in drinking water, at the currently enforced Maximum Contaminant Level (MCL) concentration of 5 ppb are extrapolated from animal bioassay data using a conservative, linear dose-response model. These TCE-related risks are compared …
Date:
December 8, 1994
Creator:
Bogen, K. T.; Slone, T.; Gold, L. S.; Manley, N. & Revzan, K.
Object Type:
Report
System:
The UNT Digital Library
In-vessel fluid flow measurements using thermocouples cross-correlation.
Fluid flow rate in high temperature and pressure vessels can be difficult to measure due to the associated harsh environment, inaccessible locations and pressure boundary integrity concerns. However, by using quick response miniature thermocouples to measure the naturally occurring temperature variations within the flow, the fluid velocity can be inferred from the transit time analysis. This flow measurement technique has other advantages such as the flow profile is not significantly disturbed, no additional flow restrictions introduced and the system fiction factor is not increased. Furthermore, since the measured flow rate is generally unaffected by the global system dynamics, such as heat increases or losses, as well as changes in the flow regimes, the location of the thermocouple pairs is extremely flexible. Due to the mentioned advantages, the thermocouple cross-correlation flow measurement method has been developed for use at the Purdue University Multi-Dimensional Integral Test Assembly (PUMA). Currently, thermocouple cross-correlation technique is used to measure the Reactor Pressure Vessel downcomer fluid velocity and the suppression pool in-vessel natural circulation velocity.
Date:
May 8, 1998
Creator:
NguyenLe, Q.
Object Type:
Article
System:
The UNT Digital Library
Progress toward hydrogen peroxide micropulsion
A new self-pressurizing propulsion system has liquid thrusters and gas jet attitude control without heavy gas storage vessels. A pump boosts the pressure of a small fraction of the hydrogen peroxide, so that reacted propellant can controllably pressurize its own source tank. The warm decomposition gas also powers the pump and is supplied to the attitude control jets. The system has been incorporated into a prototype microsatellite for terrestrial maneuvering tests. Additional progress includes preliminary testing of a bipropellant thruster, and storage of unstabilized hydrogen peroxide in small sealed tanks.
Date:
July 8, 1999
Creator:
Whitehead, J. C.; Dittman, M. D. & Ledebuhr, A. G.
Object Type:
Article
System:
The UNT Digital Library
Low-temperature MOCVD growth of oriented PbZr{sub x}Ti{sub 1-x}O{sub 3} thin films on Si substrates.
Polycrystalline Pb(Zr{sub 0.6}Ti{sub 0.4})O{sub 3} (PZT) thin films, 3000-6000 {angstrom} thick, have been grown by metal-organic chemical vapor deposition (MOCVD) on (111)Pt/Ti/SiO{sub 2}/Si substrates at temperatures as low as 450-525 C. Random and (111)-oriented, or occasionally (100)-oriented, PZT films can be deposited directly on (111)Pt/Ti/SiO{sub 2}/Si. In addition, highly (100)-oriented films can be deposited consistently by using 150-250 {angstrom} thick (100)-oriented PbTiO{sub 3} (PT) or TiO{sub 2} as a template. Films were characterized by X-ray diffraction, electron microscopy, and electrical measurements. The as-grown (100)-oriented films on (111)Pt/TiSiO{sub 2}/Si substrates exhibited dielectric constants ({var_epsilon}{sub r}) of up to 600, remnant polarization (P{sub r}) of 40 {micro}C/cm{sup 2}, coercive field of 55 kV/cm, and breakdown field of 2-6 x 10{sub 7} V/m.
Date:
May 8, 1998
Creator:
Chen, N.
Object Type:
Article
System:
The UNT Digital Library
Preserving Alaska's early Cold War legacy.
The US Air Force owns and operates numerous facilities that were constructed during the Cold War era. The end of the Cold War prompted many changes in the operation of these properties: missions changed, facilities were modified, and entire bases were closed or realigned. The widespread downsizing of the US military stimulated concern over the potential loss of properties that had acquired historical value in the context of the Cold War. In response, the US Department of Defense in 1991 initiated a broad effort to inventory properties of this era. US Air Force installations in Alaska were in the forefront of these evaluations because of the role of the Cold War in the state's development and history and the high interest on the part of the Alaska State Historic Preservation Officer (SHPO) in these properties. The 611th Air Support Group (611 ASG) owns many of Alaska's early Cold War properties, most were associated with strategic air defense. The 611 ASG determined that three systems it operates, which were all part of the integrated defense against Soviet nuclear strategic bomber threat, were eligible for the National Register of Historic Places (NRHP) and would require treatment as historic properties. These systems include …
Date:
March 8, 1999
Creator:
Hoffecker, J. & Whorton, M.
Object Type:
Article
System:
The UNT Digital Library
THE 15 LAYER SILICON DRIFT DETECTOR TRACKER IN EXPERIMENT 896.
Large linear silicon drift detectors have been developed and are in production for use in several experiments. Recently 15 detectors were used as a tracking device in BNL-AGS heavy ion experiment (E896). The detectors were successfully operated in a 6.2 T magnetic field. The behavior of the detectors, such as drift uniformity, resolution, and charge collection efficiency are presented. The effect of the environment on the detector performance is discussed. Some results from the experimental run are presented. The detectors performed well in an experimental environment. This is the first tracking application of these detectors.
Date:
November 8, 1998
Creator:
Pandy, S. U.
Object Type:
Article
System:
The UNT Digital Library
Basin Analysis of the Mississippi Interior Salt Basin and Petroleum System Modeling of the Jurassic Smackover Formation, Eastern Gulf Coastal Plain
The objective is to provide a comprehensive geologic analysis of the Mississippi Interior Salt Basin.
Date:
April 8, 1998
Creator:
Mancini, Ernest A.
Object Type:
Report
System:
The UNT Digital Library
Manufacturing diamond films using copper vapour lasers
Fifty nanosecond pulses of visible light have been used to produce hard, hydrogen-free diamond-like-carbon (DLC) films at irradiances between 5 x 10{sup 8} and 5 x 10{sup 10} W/cm{sup 2} The films were characterized by a number of techniques including: Raman spectroscopy, Electron Energy Loss Spectroscopy (EELS), atomic force microscopy, and spectroscopic ellipsometry. The cost for manufacturing DLC with high average power, high-pulse repetition frequency, visible light is low enough to compete with other diamond thin film production methods.
Date:
January 8, 1996
Creator:
McLean, M., LLNL
Object Type:
Article
System:
The UNT Digital Library
National Ignition Facility start-up/operations engineering and special equipment construction health and safety plan
This document sets forth the responsibilities, interfaces, guidelines, rules, policy, and regulations for all workers involved in the S/O and SE construction, installation, and acceptance testing. This document is enforced from the first day that S/O and SE workers set foot on the NIF construction site until the end of the Project at Critical Decision 4. This document is applicable only to site activities, which are defined as those that occur within the perimeter of the fenced-off NIF construction zone and the Target Chamber Assembly Area (Helipad). The associated Special Equipment laydown and construction support areas listed in Appendix B are not under this plan; their safety provisions are discussed in the Appendix. Prototype and other support activities, such as the Amplifier Laboratory and Frame Assembly Unit assembly area, are not included in this plan. After completion of the Operational Readiness Review, the Facility Safety Procedure, Operational Safety Requirements, and Operational Safety Procedures are the governing safety documents for the operating facility. The S/O and SE project elements are required to implement measures that create a universal awareness of and promote safe job practices at the site. This includes all Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory, Sandia …
Date:
May 8, 1998
Creator:
Huddleston, P. C.
Object Type:
Report
System:
The UNT Digital Library
Subcarrier multiplexing system with built-in dispersion reduction
Dispersion is effectively reduced in a 1550-nm subcarrier-multiplexed fiber link by using optical pre-filtering at the receiver. Recent experimental results demonstrate transmission of two 2.5 Gbit/s data channels over 220 km of ordinary single-mode fiber.
Date:
September 8, 1995
Creator:
Sargis, P. D.; Haigh, R. E. & McCammon, K. G.
Object Type:
Article
System:
The UNT Digital Library
Uranium and Plutonium Solution Assays by Transmission-Corrected X-Ray Fluorescence
We have refined and tested a previously developed x-ray fluorescence analysis technique for uranium and plutonium solutions that compensates for variations in the absorption of the exciting gamma rays and fluorescent x-rays. We use {sup 57}Co to efficiently excite the K lines of the elements, and a mixed {sup 57}Co plus {sup 153}Gd transmission source to correct for variations in absorption. The absorption correction is a unique feature of our technique. It is possible to accurately calibrate the system with a single solution standard. There does not need to be a close match in composition (i.e., absorption) between the standard(s) and solutions to be analyzed. Specially designed equipment incorporates a planar intrinsic germanium detector, excitation and transmission radioisotopes, and specimen holder. The apparatus can be inserted into a rubber glove of a glovebox, keeping the apparatus outside and the solutions inside the glovebox, thereby protecting the user and the equipment from possible contamination. An alternate design may be used in chemical reprocessing plants, providing continuous monitoring, by measuring the trans-actinides through stainless steel piping. This technique has been tested at the Bochvar Research Institute of Inorganic Materials in Moscow for possible use in the Russian complex of nuclear facilities. This …
Date:
September 8, 1999
Creator:
Ryon, R. W.; Ruhter, W. D.; Rudenko, V.; Sirontinin, A. & Petrov, A. A.
Object Type:
Article
System:
The UNT Digital Library