A Five-Watts G-M/J-T Refrigerator for Lhe Target at Bnl. (open access)

A Five-Watts G-M/J-T Refrigerator for Lhe Target at Bnl.

A five-watts G-M/J-T refrigerator was built and installed for the high-energy physics research at Brookhaven National Laboratory in 2001. A liquid helium target of 8.25 liters was required for an experiment in the proton beam line at the Alternating Gradient Synchrotron (AGS) of BNL. The large radiation heat load towards the target requires a five-watts refrigerator at 4.2 K to support a liquid helium flask of 0.2 meter in diameter and 0.3 meter in length which is made of Mylar film of 0.35 mm in thickness. The liquid helium flask is thermally exposed to the vacuum windows that are also made of 0.35 mm thickness Mylar film at room temperature. The refrigerator uses a two-stage Gifford-McMahon cryocooler for precooling the Joule-Thomson circuit that consists of five Linde-type heat exchangers. A mass flow rate of 0.8 {approx} 1.0 grams per second at 17.7 atm is applied to the refrigerator cold box. The two-phase helium flows between the liquid target and liquid/gas separator by means of thermosyphon. The paper presents the system design as well as the test results including the control of thermal oscillation.
Date: July 16, 2001
Creator: Jia, L. X.; Wang, L.; Addessi, L.; Miglionico, G.; Martin, D.; Leskowicz, J. et al.
Object Type: Article
System: The UNT Digital Library
The Evolution of Stellarator Theory at Princeton (open access)

The Evolution of Stellarator Theory at Princeton

This paper describes the evolution of the stellarator program at the Princeton Plasma Physics Laboratory, beginning with the legend of how Lyman Spitzer, Jr. first conceived the stellarator concept.
Date: November 16, 2001
Creator: Johnson, John L.
Object Type: Report
System: The UNT Digital Library
Tevatron optics with magnet moves for Roman pots at CDF (open access)

Tevatron optics with magnet moves for Roman pots at CDF

CDF would like to install high precision track detectors. There is ample room on A-sector side, but space needs to be created at B11. The favored plan is to shove the first 3 B11 dipoles inwards toward the IP by 2.274 m. This would require removal of the inert Q1 quadrupole and its spool plus an extensive number of other mechanical and cryogenic modifications. The orbit distortion these modifications introduce would then be compensated by shifting the six B16 and B17 dipoles outwards by about half that amount. Space for this dipole move could be generated by replacing the 72 inch spool at B18 with a short 43 inch spool, and removing the 16.5 inch spacer after B17-5. The above scheme certainly recloses the orbit, and doesn't require the detector to move. However, by moving the B16 and B17 dipoles, the B17 and B18 arc quadrupoles also get shifted downstream--B17 by 1.115 m, and B18 by 0.696 m. Longitudinal movements of arc quads by such large fractions of their magnetic lengths will clearly impact the overall machine optics.
Date: August 16, 2001
Creator: Johnstone, John A.
Object Type: Report
System: The UNT Digital Library
Microbial Communities Model Parameter Calculation for TSPA/SR (open access)

Microbial Communities Model Parameter Calculation for TSPA/SR

This calculation has several purposes. First the calculation reduces the information contained in ''Committed Materials in Repository Drifts'' (BSC 2001a) to useable parameters required as input to MING V1.O (CRWMS M&O 1998, CSCI 30018 V1.O) for calculation of the effects of potential in-drift microbial communities as part of the microbial communities model. The calculation is intended to replace the parameters found in Attachment II of the current In-Drift Microbial Communities Model revision (CRWMS M&O 2000c) with the exception of Section 11-5.3. Second, this calculation provides the information necessary to supercede the following DTN: M09909SPAMING1.003 and replace it with a new qualified dataset (see Table 6.2-1). The purpose of this calculation is to create the revised qualified parameter input for MING that will allow {Delta}G (Gibbs Free Energy) to be corrected for long-term changes to the temperature of the near-field environment. Calculated herein are the quadratic or second order regression relationships that are used in the energy limiting calculations to potential growth of microbial communities in the in-drift geochemical environment. Third, the calculation performs an impact review of a new DTN: M00012MAJIONIS.000 that is intended to replace the currently cited DTN: GS9809083 12322.008 for water chemistry data used in the current …
Date: July 16, 2001
Creator: Jolley, D.
Object Type: Report
System: The UNT Digital Library
Quarterly Progress Report for the Chemical and Energy Research Section of the Chemical Technology Division: July-September 1999 (open access)

Quarterly Progress Report for the Chemical and Energy Research Section of the Chemical Technology Division: July-September 1999

This report summarizes the major activities conducted in the Chemical and Energy Research Section of the Chemical Technology Division at Oak Ridge National Laboratory (ORNL) during the period July-September 1999. The section conducts basic and applied research and development in chemical engineering, applied chemistry, and bioprocessing, with an emphasis on energy-driven technologies and advanced chemical separations for nuclear and waste applications. The report describes the various tasks performed within ten major areas of research: Hot Cell Operations, Process Chemistry, Molten Salt Reactor Experiment (MSRE) Remediation Studies, Chemistry Research, Physical Properties Research, Biochemical Engineering, Separations and Materials Synthesis, Fluid Structures and Properties, Biotechnology Research, and Molecular Studies. The name of a technical contact is included with each task described, and readers are encouraged to contact these individuals if they need additional information. Activities conducted within the area of the Cell Operations involved the testing of two continuously stirred tank reactors in series to evaluate the Savannah River-developed process of small-tank tetraphenylborate precipitation to remove cesium, strontium and transuranics from supernatant. Within the area of Process Chemistry, various topics related to solids formation in process solutions from caustic treatment of Hanford sludge were addressed. Saltcake dissolution efforts continued, including the development of …
Date: April 16, 2001
Creator: Jubin, R. T.
Object Type: Report
System: The UNT Digital Library
Agriculture in Afghanistan and Neighboring Asian Countries (open access)

Agriculture in Afghanistan and Neighboring Asian Countries

Agriculture (as measured by share of gross domestic product and employment) is a significant economic sector in seven Central and South Asian countries: Afghanistan, Iran, Kyrgyzstan, Pakistan, Tajikistan, Turkmenistan, and Uzbekistan. All of these countries are net food importers. Some have experienced successive years of drought, which has contributed to noticeable declines in agricultural output and the need to increase commodity imports. The United Nations’ World Food Program reports that both Afghanistan and Tajikistan are currently in need of emergency food assistance to cover sizable food deficits. The food outlook in Afghanistan is made uncertain by ongoing military conflict.
Date: November 16, 2001
Creator: Jurenas, Remy
Object Type: Report
System: The UNT Digital Library
China's Proliferation of Weapons of Mass Destruction and Missiles: Current Policy Issues (open access)

China's Proliferation of Weapons of Mass Destruction and Missiles: Current Policy Issues

This report provides a brief background analysis and recent developments regarding China’s Proliferation of Weapons of Mass Destruction and Missiles. The report includes topics such as: Recent Proliferation Transfers, chemical, nuclear, and missile technology sales to Iran, Pakistan, Libya, Syria, trade controls, nonproliferation and arms control.
Date: May 16, 2001
Creator: Kan, Shirley A.
Object Type: Report
System: The UNT Digital Library
A Sampling End Effector for Steel Waste Tank Walls (open access)

A Sampling End Effector for Steel Waste Tank Walls

None
Date: January 16, 2001
Creator: Killough, S.M.
Object Type: Article
System: The UNT Digital Library
Field Investigation to Determine the Extent of Sediment Recontamination at the United Heckathorn Superfund Site, Richmond, California (open access)

Field Investigation to Determine the Extent of Sediment Recontamination at the United Heckathorn Superfund Site, Richmond, California

This field investigation was undertaken to determine the present condition of sediment in Lauritzen Channel and Parr Canal approximately 2 years after completion of sediment remedial actions at the United Heckathorn Superfund site. The study was designed to supplement the post-remediation monitoring program by determining the extent and identifying potential sources of observed pesticide contamination in marine sediments near the site. Core samples collected from Lauritzen Channel and Parr Canal in July 1999 were described geologically, and samples were prepared from different sediment types, such as younger bay mud or older bay mud. Sediment samples were analyzed for grain size, organic carbon, and DDT compounds. Only minor changes have occurred in Parr Canal since remedial actions were taken in 1996-1997, but in Lauritzen Channel, DDT concentrations exceed the remedial goal of 590 ug/kg dry weight in nearly all the unconsolidated sediment (younger bay mud, sand, and disturbed older bay mud). The source of contaminated sediment could not be confirmed by this study; there was no clear correlation between high DDT concentrations and sediment remaining between the pilings, as was originally suspected. There also was no correlation between high DDT concentrations in sediment and the locations of outfalls, although some of …
Date: November 16, 2001
Creator: Kohn, Nancy P. & Gilmore, Tyler J.
Object Type: Report
System: The UNT Digital Library
Fundamental Statistical Descriptions of Plasma Turbulence in Magnetic Fields (open access)

Fundamental Statistical Descriptions of Plasma Turbulence in Magnetic Fields

A pedagogical review of the historical development and current status (as of early 2000) of systematic statistical theories of plasma turbulence is undertaken. Emphasis is on conceptual foundations and methodology, not practical applications. Particular attention is paid to equations and formalism appropriate to strongly magnetized, fully ionized plasmas. Extensive reference to the literature on neutral-fluid turbulence is made, but the unique properties and problems of plasmas are emphasized throughout. Discussions are given of quasilinear theory, weak-turbulence theory, resonance-broadening theory, and the clump algorithm. Those are developed independently, then shown to be special cases of the direct-interaction approximation (DIA), which provides a central focus for the article. Various methods of renormalized perturbation theory are described, then unified with the aid of the generating-functional formalism of Martin, Siggia, and Rose. A general expression for the renormalized dielectric function is deduced and discussed in detail. Modern approaches such as decimation and PDF methods are described. Derivations of DIA-based Markovian closures are discussed. The eddy-damped quasinormal Markovian closure is shown to be nonrealizable in the presence of waves, and a new realizable Markovian closure is presented. The test-field model and a realizable modification thereof are also summarized. Numerical solutions of various closures for some …
Date: February 16, 2001
Creator: Krommes, John A.
Object Type: Report
System: The UNT Digital Library
Probability Distribution for Flowing Interval Spacing (open access)

Probability Distribution for Flowing Interval Spacing

The purpose of this analysis is to develop a probability distribution for flowing interval spacing. A flowing interval is defined as a fractured zone that transmits flow in the Saturated Zone (SZ), as identified through borehole flow meter surveys (Figure 1). This analysis uses the term ''flowing interval spacing'' as opposed to fractured spacing, which is typically used in the literature. The term fracture spacing was not used in this analysis because the data used identify a zone (or a flowing interval) that contains fluid-conducting fractures but does not distinguish how many or which fractures comprise the flowing interval. The flowing interval spacing is measured between the midpoints of each flowing interval. Fracture spacing within the SZ is defined as the spacing between fractures, with no regard to which fractures are carrying flow. The Development Plan associated with this analysis is entitled, ''Probability Distribution for Flowing Interval Spacing'', (CRWMS M&O 2000a). The parameter from this analysis may be used in the TSPA SR/LA Saturated Zone Flow and Transport Work Direction and Planning Documents: (1) ''Abstraction of Matrix Diffusion for SZ Flow and Transport Analyses'' (CRWMS M&O 1999a) and (2) ''Incorporation of Heterogeneity in SZ Flow and Transport Analyses'', (CRWMS M&O …
Date: May 16, 2001
Creator: Kuzio, S.
Object Type: Report
System: The UNT Digital Library
Efficient Error Calculation for Multiresolution Texture-Based Volume Visualization (open access)

Efficient Error Calculation for Multiresolution Texture-Based Volume Visualization

Multiresolution texture-based volume visualization is an excellent technique to enable interactive rendering of massive data sets. Interactive manipulation of a transfer function is necessary for proper exploration of a data set. However, multiresolution techniques require assessing the accuracy of the resulting images, and re-computing the error after each change in a transfer function is very expensive. They extend their existing multiresolution volume visualization method by introducing a method for accelerating error calculations for multiresolution volume approximations. Computing the error for an approximation requires adding individual error terms. One error value must be computed once for each original voxel and its corresponding approximating voxel. For byte data, i.e., data sets where integer function values between 0 and 255 are given, they observe that the set of error pairs can be quite large, yet the set of unique error pairs is small. instead of evaluating the error function for each original voxel, they construct a table of the unique combinations and the number of their occurrences. To evaluate the error, they add the products of the error function for each unique error pair and the frequency of each error pair. This approach dramatically reduces the amount of computation time involved and allows …
Date: October 16, 2001
Creator: LaMar, E.; Hamann, B. & Joy, K. I.
Object Type: Article
System: The UNT Digital Library
Studies of jet energy resolution (open access)

Studies of jet energy resolution

None
Date: January 16, 2001
Creator: Lami, S.; Bocci, A. & Kuhlmann, S.
Object Type: Article
System: The UNT Digital Library
Neutron Capture and Transmission Measurements and Resonance Parameter Analysis of Samarium (open access)

Neutron Capture and Transmission Measurements and Resonance Parameter Analysis of Samarium

The purpose of the present work is to accurately measure the neutron cross sections of samarium. The most significant isotope is {sup 149}Sm, which has a large neutron absorption cross section at thermal energies and is a {sup 235}U fission product with a 1% yield. Its cross sections are thus of concern to reactor neutronics. Neutron capture and transmission measurements were performed by the time-of-flight technique at the Rensselaer Polytechnic institute (RPI) LINAC facility using metallic and liquid Sm samples. The capture measurements were made at the 25 meter flight station with a multiplicity-type capture detector, and the transmission total cross-section measurements were performed at 15- and 25-meter flight stations with {sup 6}Li glass scintillation detectors. Resonance parameters were determined by a combined analysis of six experiments (three capture and three transmission) using the multi-level R-matrix Bayesian code SAMMY version M2. The significant features of this work are as follows. Dilute samples of samarium nitrate in deuterated water (D{sub 2}O) were prepared to measure the strong resonances at 0.1 and 8 eV without saturation. Disk-shaped spectroscopic quartz cells were obtained with parallel inner surfaces to provide a uniform thickness of solution. The diluent feature of the SAMMY program was used …
Date: July 16, 2001
Creator: Leinweber, G.; Burke, J. A.; Knox, H. D.; Drindak, N. J.; Mesh, D. W.; Haines, W. T. et al.
Object Type: Report
System: The UNT Digital Library
The Cost of Prescription Drugs for the Uninsured Elderly and Legislative Approaches (open access)

The Cost of Prescription Drugs for the Uninsured Elderly and Legislative Approaches

The purpose of this report is to explain why many of those who are least able to afford high drug costs are those who are most frequently charged the most. This report describes the basic economic theory underlying price differentiation and, in the context of the pharmaceutical market, analyzes the role and behavior of pharmacy benefit managers (PBMs), pharmaceutical manufacturers, and retail pharmacies, respectively. It also looks at a number of the criticisms that have been made of the practice of differential pricing. Finally, this report discusses various policy approaches aimed at assisting the elderly to purchase prescription drugs.
Date: January 16, 2001
Creator: Library of Congress. Congressional Research Service. Resources, Science, and Industry Division.
Object Type: Report
System: The UNT Digital Library
SiC-BASED HYDROGEN SELECTIVE MEMBRANES FOR WATER-GAS-SHIFT REACTION (open access)

SiC-BASED HYDROGEN SELECTIVE MEMBRANES FOR WATER-GAS-SHIFT REACTION

This technical report summarizes our activities conducted in Yr II. In Yr I we successfully demonstrated the feasibility of preparing the hydrogen selective SiC membrane with a chemical vapor deposition (CVD) technique. In addition, a SiC macroporous membrane was fabricated as a substrate candidate for the proposed SiC membrane. In Yr II we have focused on the development of a microporous SiC membrane as an intermediate layer between the substrate and the final membrane layer prepared from CVD. Powders and supported thin silicon carbide films (membranes) were prepared by a sol-gel technique using silica sol precursors as the source of silicon, and phenolic resin as the source of carbon. The powders and films were prepared by the carbothermal reduction reaction between the silica and the carbon source. The XRD analysis indicates that the powders and films consist of SiC, while the surface area measurement indicates that they contain micropores. SEM and AFM studies of the same films also validate this observation. The powders and membranes were also stable under different corrosive and harsh environments. The effects of these different treatments on the internal surface area, pore size distribution, and transport properties, were studied for both the powders and the membranes …
Date: October 16, 2001
Creator: Liu, Paul K.T.
Object Type: Report
System: The UNT Digital Library
Flowsheet Development for the New Neptunium Oxalate Precipitation System (open access)

Flowsheet Development for the New Neptunium Oxalate Precipitation System

This report summarizes laboratory development work and provides flowsheet guidelines for neptunium (IV) oxalate precipitation in the new HB-Line.
Date: August 16, 2001
Creator: Luerkens, D.W.
Object Type: Report
System: The UNT Digital Library
Products of pertechnetate radiolysis in highly alkaline solution: structure of TcO2(dot)xH2O (open access)

Products of pertechnetate radiolysis in highly alkaline solution: structure of TcO2(dot)xH2O

None
Date: August 16, 2001
Creator: Lukens, Wayne; Bucher, Jerome; Edelstein, Norman & Shuh, David
Object Type: Article
System: The UNT Digital Library
The Vietnam-U.S. Bilateral Trade Agreement (open access)

The Vietnam-U.S. Bilateral Trade Agreement

None
Date: January 16, 2001
Creator: Manyin, Mark E.
Object Type: Report
System: The UNT Digital Library
Credit Documentation and the Mark 15 Subroutine (open access)

Credit Documentation and the Mark 15 Subroutine

This report documents the rewrite of the heat transfer subroutine. Part of the process of preparing the Mark 15 assembly for production operation is the development of thermal-hydraulic limits for the assembly. These limits require, among other items, the development of a Mark 15 assembly subroutine for the CREDIT code.
Date: August 16, 2001
Creator: McAllister, J.E.
Object Type: Report
System: The UNT Digital Library
Chromaticity Measurements Using Phase Modulated RF and Vector Signal Analyzers (open access)

Chromaticity Measurements Using Phase Modulated RF and Vector Signal Analyzers

Chromaticity measurements are usually done by changing the energy of the beam by a known amount and measuring the change in betatron tune with a spectrum analyzer. The energy change is done by adjusting the RF frequency. The change in RF frequency is made large enough so that the change in betatron tune can be seen. If synchrotron motion is present in the beam, then measuring the change in betatron tune can be difficult. This note will outline a method to measure the change in betatron tune by phase-modulating the RF and measuring the phase modulated betatron spectrum Extremely small resolution bandwidths are available on modern vector signal analyzers. A small resolution bandwidth is equivalent to measuring the chromaticity many times and averaging the results. This would permit much smaller shifts in betatron tunes to be measured. The phase-modulated signal consists of sidebands whose amplitudes are given by Bessel functions. The complication of the Bessel functions can be removed if the vector signal analyzer is capable of phase demodulation. The sign of the chromaticity can be determined by observing the modulation spectrum at both betatron sidebands.
Date: February 16, 2001
Creator: McGinnis, Dave
Object Type: Report
System: The UNT Digital Library
Energy-efficiency labels and standards: A guidebook for appliances, equipment and lighting (open access)

Energy-efficiency labels and standards: A guidebook for appliances, equipment and lighting

Energy-performance improvements in consumer products are an essential element in any government's portfolio of energy-efficiency and climate change mitigation programs. Governments need to develop balanced programs, both voluntary and regulatory, that remove cost-ineffective, energy-wasting products from the marketplace and stimulate the development of cost-effective, energy-efficient technology. Energy-efficiency labels and standards for appliances, equipment, and lighting products deserve to be among the first policy tools considered by a country's energy policy makers. The U.S. Agency for International Development (USAID) and the United Nations Foundation (UNF) recognize the need to support policy makers in their efforts to implement energy-efficiency standards and labeling programs and have developed this guidebook, together with the Collaborative Labeling and Appliance Standards Program (CLASP), as a primary reference. This guidebook was prepared over the course of the past year with significant contribution from the authors and reviewers mentioned previously. Their diligent participation has made this the international guidance tool it was intended to be. The lead authors would also like to thank the following individuals for their support in the development, production, and distribution of the guidebook: Marcy Beck, Elisa Derby, Diana Dhunke, Ted Gartner, and Julie Osborn of Lawrence Berkeley National Laboratory as well as Anthony Ma …
Date: February 16, 2001
Creator: McMahon, James E. & Wiel, Stephen
Object Type: Report
System: The UNT Digital Library
The Supreme Court Addresses Corps of Engineers Jurisdiction Over "Isolated Waters": The SWANCC Decision (open access)

The Supreme Court Addresses Corps of Engineers Jurisdiction Over "Isolated Waters": The SWANCC Decision

On January 9, 2001, the Supreme Court handed down Solid Waste Agency of Northern Cook County (SWANCC) v. U.S. Army Corps of Engineers. At issue in SWANCC was the scope of Clean Water Act section 404, which requires permits for the discharge of dredged or fill materials into "navigable waters," defined by the Act as "waters of the United States." Section 404 is the charter for the federal wetlands permitting program.
Date: February 16, 2001
Creator: Meltz, Robert & Copeland, Claudia
Object Type: Report
System: The UNT Digital Library
Stiff Temperature Profiles in JT-60U ELMy H-mode Plasmas (open access)

Stiff Temperature Profiles in JT-60U ELMy H-mode Plasmas

The 'stiffness' of thermal transport in ELMy H-modes [edge localized high-confinement modes] is examined in a series of carefully chosen JT-60U plasmas, and measured temperatures are compared with the predictions of several transport models. A heating power scan with constant T(subscript ''ped''), a scan of pedestal temperature, T(subscript ''ped''), with constant heating power, and an on-axis/off-axis heating comparison are presented. In the power scan a 45% increase in heating (and a 12% density rise) produces an approximately fixed core temperature profile in a group of five plasmas with the same pedestal temperature. With fixed heating power, we find that a 30-40% increase in T(subscript ''ped'') is associated with similar increases in core temperature. Heating in the deep core is varied by employing different groups of neutral beams that deposit their power near the magnetic axis and farther from the axis. In these plasmas, on-axis heating produces slightly more peaked temperature profiles, although they have 60% more heating power inside r = a/2. Transport models are tested by solving the power balance equations to predict temperatures, which are then compared to the measurements. Predictions of the RLWB and IFS/PPPL models generally agree with the measured temperatures outside r approximately 0.3a, but …
Date: October 16, 2001
Creator: Mikkelsen, D.R.; Urano, H.; Shirai, H.; Takizuka, T.; Kamada, Y.; Hatae, T. et al.
Object Type: Report
System: The UNT Digital Library