205 kA pulse power supply for neutrino focusing horns (open access)

205 kA pulse power supply for neutrino focusing horns

A new underground beamline is being constructed at Fermilab to generate and focus a beam of neutrinos on a detector 450 miles away in Soudan, Minnesota. A compact modulator utilizing capacitive energy storage and SCRs as the switching element has been built and tested at Fermilab. The 0.9 F capacitor bank operates at less than 1 kV. It delivers its output of up to 240 kA directly to the two series connected focusing horns via a multi-layer radiation hard stripline [1]. Dual pulse width capability allows for ready selection of 5.2 ms, for slow beam spills, or 2.6 ms operation for reduced thermal stresses on the focusing horns during fast spill. Intended for installation in an underground equipment room, the design incorporates several novel features to facilitate transport, installation, and maintenance. Various designs were examined to arrive at the most economical approach for providing the high pulse currents to the horns located in the very high radiation field, up to 3 x 10{sup 7} kRads/yr absorbed dose of the beamline. These included charge recovery and electronic polarity reversal systems. The direct coupling approach was selected for its overall economy and compactness. The system has been operational for several months and …
Date: June 21, 2002
Creator: Kenneth R. Bourkland, Kevin Roon and David Tinsley
System: The UNT Digital Library
2002 Gordon Research Conference on CATALYSIS. Final Progress Report (open access)

2002 Gordon Research Conference on CATALYSIS. Final Progress Report

The Gordon Research Conference (GRC) on CATALYSIS was held at Colby-Sawyer College from 6/23/02 thru 6/28/02. The Conference was well-attended with 118 participants. The attendees represented the spectrum of endeavor in this field coming from academia, industry, and government laboratories, both U.S. and foreign scientists, senior researchers, young investigators, and students.
Date: June 28, 2002
Creator: unknown
System: The UNT Digital Library
[3H]Azidodantrolene photoaffinity labeling, synthetic domain peptides and monoclonal antibody reactivity identify the dantrolene binding sequence on RyR1 (open access)

[3H]Azidodantrolene photoaffinity labeling, synthetic domain peptides and monoclonal antibody reactivity identify the dantrolene binding sequence on RyR1

Dantrolene is a drug that suppresses intracellular Ca2+ release from sarcoplasmic reticulum in normal skeletal muscle and is used as a therapeutic agent in individuals susceptible to malignant hyperthermia. Though its precise mechanism of action has not been elucidated, we have identified the N-terminal region (amino acids 1-1400) of the skeletal muscle isoform of the ryanodine receptor (RyR1), the primary Ca2+ release channel in sarcoplasmic reticulum, as a molecular target for dantrolene using the photoaffinity analog [3H]azidodantrolene(1). Here, we demonstrate that heterologously expressed RyR1 retains its capacity to be specifically labeled with [3H]azidodantrolene,indicating that muscle specific factors are not required for this ligand-receptor interaction. Synthetic domain peptides of RyR1, previously shown to affect RyR1 function in vitro and in vivo, were exploited as potential drug binding site mimics and used in photoaffinity labeling experiments. Only DP1 and DP1-2, peptide s containing the amino acid sequence corresponding to RyR1 residues 590-609, were specifically labeled by [3H]azidodantrolene. A monoclonal anti-RyR1 antibody which recognizes RyR1 and its 1400 amino acid N-terminal fragment, recognizes DP1 and DP1-2 in both Western blots and immunoprecipitation assays, and specifically inhibits [3H]azidodantrolene photolabeling of RyR1 and its N-terminal fragment in sarcoplasmic reticulum. Our results indicate that synthetic domain …
Date: June 14, 2002
Creator: Paul-Pletzer, Kalanethee; Yamamoto, Takeshi; Bhat, Manju B.; Ma, Jianjie; Ikemoto, Noriaki; Jimenez, Leslie S. et al.
System: The UNT Digital Library
Abort Gap Cleaning in RHIC (open access)

Abort Gap Cleaning in RHIC

During the RHIC Au-run in 2001 the 200 MHz storage cavity system was used for the first time. The rebucketing procedure caused significant beam debunching in addition to amplifying debunching due to other mechanisms. At the end of a four hour store, debunched beam could account for approximately 30%-40% of the total beam intensity. Some of it will be in the abort gap. In order to minimize the risk of magnet quenching due to uncontrolled beam losses at the time of a beam dump, a combination of a fast transverse kicker and copper collimators were used to clean the abort gap. This report gives an overview of the gap cleaning procedure and the achieved performance.
Date: June 3, 2002
Creator: Drees, A.; Ahrens, L.; Fliller, R., III; Gassner, D.; McIntyre, G. T.; Michnoff, R. et al.
System: The UNT Digital Library
Abrasive wear behavior of heat-treated ABC-silicon carbide (open access)

Abrasive wear behavior of heat-treated ABC-silicon carbide

Hot-pressed silicon carbide, containing aluminum, boron, and carbon additives (ABC-SiC), was subjected to three-body and two-body wear testing using diamond abrasives over a range of sizes. In general, the wear resistance of ABC-SiC, with suitable heat treatment, was superior to that of commercial SiC.
Date: June 17, 2002
Creator: Zhang, Xiao Feng; Lee, Gun Y.; Chen, Da; Ritchie, Robert O. & De Jonghe, Lutgard C.
System: The UNT Digital Library
Accelerating and Colliding Polarized Protons in RHIC With Siberian Snakes (open access)

Accelerating and Colliding Polarized Protons in RHIC With Siberian Snakes

We successfully injected polarized protons in both RHIC rings and maintained polarization during acceleration up to 100 GeV per ring using two Siberian snakes in each ring. Each snake consists of four helical superconducting dipoles which rotate the polarization by 180{sup o} about a horizontal axis. This is the first time that polarized protons have been accelerated to 100 GeV. We report on our experiences during commissioning and operation of collider with polarized protons.
Date: June 2, 2002
Creator: Roser, T.; Ahrens, L.; Alessi, J.; Bai, M.; Beebe-Wang, J.; Brennan, J. M. et al.
System: The UNT Digital Library
Accelerator optimization using a network control and acquisition system (open access)

Accelerator optimization using a network control and acquisition system

Accelerator optimization requires detailed study of many parameters, indicating the need for remote control and automated data acquisition systems. A control and data acquisition system based on a network of commodity PCs and applications with standards based inter-application communication is being built for the l'OASIS accelerator facility. This system allows synchronous acquisition of data at high (> 1 Hz) rates and remote control of the accelerator at low cost, allowing detailed study of the acceleration process.
Date: June 30, 2002
Creator: Geddes, Cameron, G.R.; Catravas, P.E.; Faure, Jerome; Toth, Csaba; van Tilborg, J. & Leemans, Wim P.
System: The UNT Digital Library
ACCELERATOR PHYSICS MODEL OF EXPECTED BEAM LOSS ALONG THE SNS ACCELERATOR FACILITY DURING NORMAL OPERATION. (open access)

ACCELERATOR PHYSICS MODEL OF EXPECTED BEAM LOSS ALONG THE SNS ACCELERATOR FACILITY DURING NORMAL OPERATION.

The most demanding requirement in the design of the SNS accelerator chain is to keep the accelerator complex under hands-on maintenance. This requirement implies a hard limit for residual radiation below 100 mrem/hr at one feet from the vacuum pipe and four hours after shutdown for hundred days of normal operation. It has been shown by measurements as well as simulation [l] that this limit corresponds to 1-2 Watts/meter average beam losses. This loss level is achievable all around the machine except in specific areas where remote handling will be necessary. These areas have been identified and correspond to collimation sections and dumps where a larger amount of controlled beam loss is foreseen. Even if the average level of loss is kept under 1 W/m, there are circumstances under which transient losses occur in the machine. The prompt radiation or potential damage in the accelerator components can not be deduced from an average beam loss of 1 W/m. At the same time, controlled loss areas require a dedicated study to clarify the magnitude and distribution of the beam loss. From the front end to the target, we have estimated the most probable locations for transient losses and given an estimate …
Date: June 3, 2002
Creator: Catalan-Lasheras, N.; Cousineau, S.; Galambos, J.; Holtkamp, N.; Raparia, D.; Shafer, R. et al.
System: The UNT Digital Library
Active load management with advanced window wall systems: Research and industry perspectives (open access)

Active load management with advanced window wall systems: Research and industry perspectives

None
Date: June 1, 2002
Creator: Lee, Eleanor S.; Selkowitz, Stephen E.; Levi, Mark S.; Blanc, Steven L.; McConahey, Erin; McClintock, Maurya et al.
System: The UNT Digital Library
Active load management with advanced window wall systems: Research and industry perspectives (open access)

Active load management with advanced window wall systems: Research and industry perspectives

Advanced window wall systems have the potential to provide demand response by reducing peak electric loads by 20-30% in many commercial buildings through the active control of motorized shading systems, switchable window coatings, operable windows, and ventilated double-skin facade systems. These window strategies involve balancing daylighting and solar heat gains, heat rejection through ventilation, and night-time natural ventilation to achieve space-conditioning and lighting energy use reductions without the negative impacts on occupants associated with other demand responsive (DR) strategies. This paper explores conceptually how advanced window systems fit into the context of active load management programs, which cause customers to directly experience the time-varying costs of their consumption decisions. Technological options are suggested. We present pragmatic criteria that building owners use to determine whether to deploy such strategies. A utility's perspective is given. Industry also provides their perspectives on where the technology is today and what needs to happen to implement such strategies more broadly in the US. While there is significant potential for these advanced window concepts, widespread deployment is unlikely to occur with business-as-usual practice. Technologically, integrated window-lighting-HVAC products are underdeveloped. Implementation is hindered by fragmented labor practices, non-standard communication protocols, and lack of technical expertise. Design tools …
Date: June 1, 2002
Creator: Lee, Eleanor S.; Selkowitz, Stephen E.; Levi, Mark S.; Blanc, Steven L.; McConahey, Erin; McClintock, Maurya et al.
System: The UNT Digital Library
The Advanced Photon Source linac modulators PSpice simulation and upgrade. (open access)

The Advanced Photon Source linac modulators PSpice simulation and upgrade.

The APS linac modulators provide DC pulses to Thales 35/45-MW klystrons. The modulators are pulse forming network (PFN)-type pulsers with EMI 40-kV switch-mode charging supplies. The PFN consists of two 8-cell lines connected in parallel. EEV CX1836A thyratrons are used as discharge switches. The PSpice simulation of the modulators using OrCAD release 9.1 made it possible to find appropriate parameters of RC circuits that reduce high-frequency ringing of the pulse transformer primary voltage. In order to improve pulse top flatness (originally {+-}3%), new coils were built and installed. The coils allow discrete tuning of pulse waveforms by changing the amount of used turns. The advantage of two parallel-line PFN configurations was also used. An equivalent method using a low-voltage generator was used for PFN fine tuning.
Date: June 28, 2002
Creator: Cours, A. & Smith, T.
System: The UNT Digital Library
Advanced Test Reactor (ATR) Facility 10CFR830 Safety Basis Related to Facility Experiments (open access)

Advanced Test Reactor (ATR) Facility 10CFR830 Safety Basis Related to Facility Experiments

The Idaho National Engineering and Environmental Laboratory (INEEL) Advanced Test Reactor (ATR), a DOE Category A reactor, was designed to provide an irradiation test environment for conducting a variety of experiments. The ATR Safety Analysis Report, determined by DOE to meet the requirements of 10 CFR 830, Subpart B, provides versatility in types of experiments that may be conducted. This paper addresses two general types of experiments in the ATR facility and how safety analyses for experiments are related to the ATR safety basis. One type of experiment is more routine and generally represents greater risks; therefore this type of experiment is addressed with more detail in the safety basis. This allows individual safety analyses for these experiments to be more routine and repetitive. The second type of experiment is less defined and is permitted under more general controls. Therefore, individual safety analyses for the second type of experiment tend to be more unique from experiment to experiment. Experiments are also discussed relative to "major modifications" and DOE-STD-1027-92. Application of the USQ process to ATR experiments is also discussed.
Date: June 1, 2002
Creator: Tomberlin, Terry Alan
System: The UNT Digital Library
Advanced Test Reactor (ATR) Facility 10CFR830 Safety Basis Related to Facility Experiments (open access)

Advanced Test Reactor (ATR) Facility 10CFR830 Safety Basis Related to Facility Experiments

The Idaho National Engineering and Environmental Laboratory (INEEL) Advanced Test Reactor (ATR), a DOE Category A reactor, was designed to provide an irradiation test environment for conducting a variety of experiments. The ATR Safety Analysis Report, determined by DOE to meet the requirements of 10 CFR 830, Subpart B, provides versatility in types of experiments that may be conducted. This paper addresses two general types of experiments in the ATR facility and how safety analyses for experiments are related to the ATR safety basis. One type of experiment is more routine and generally represents greater risks; therefore this type of experiment is addressed with more detail in the safety basis. This allows individual safety analyses for these experiments to be more routine and repetitive. The second type of experiment is less defined and is permitted under more general controls. Therefore, individual safety analyses for the second type of experiment tend to be more unique from experiment to experiment. Experiments are also discussed relative to ''major modifications'' and DOE-STD-1027-92. Application of the USQ process to ATR experiments is also discussed.
Date: June 19, 2002
Creator: Tomberlin, T.A.
System: The UNT Digital Library
Airborne measurements of carbonaceous aerosols in southern Africa during the dry, biomass burning season (open access)

Airborne measurements of carbonaceous aerosols in southern Africa during the dry, biomass burning season

Particulate matter collected aboard the University of Washington's Convair-580 research aircraft over southern Africa during the dry, biomass burning season was analyzed for total carbon, organic carbon, and black carbon contents using thermal and optical methods. Samples were collected in smoke plumes of burning savanna and in regional haze. A known artifact, produced by the adsorption of organic gases on the quartz filter substrates used to collect the particulate matter samples, comprised a significant portion of the total carbon collected. Consequently, conclusions derived from the data are greatly dependent on whether or not organic carbon concentrations are corrected for this artifact. For example, the estimated aerosol co-albedo (1 - single scattering albedo), which is a measure of aerosol absorption, of the biomass smoke samples is 60 percent larger using corrected organic carbon concentrations. Thus, the corrected data imply that the biomass smoke is 60 percent more absorbing than do the uncorrected data. The black carbon to (corrected) organic carbon mass ratio (BC/OC) of smoke plume samples (0.18/2610.06) is lower than that of samples collected in the regional haze (0.25/2610.08). The difference may be due to mixing of biomass smoke with background air characterized by a higher BC/OC ratio. A simple …
Date: June 17, 2002
Creator: Kirchstetter, Thomas W.; Novakov, T.; Hobbs, Peter V. & Magi, Brian
System: The UNT Digital Library
Analog Amplitude Modulation of a High Voltage, Solid State Inductive Adder, Pulse Generator Using MOSFETS (open access)

Analog Amplitude Modulation of a High Voltage, Solid State Inductive Adder, Pulse Generator Using MOSFETS

High voltage, solid state, inductive adder, pulse generators have found increasing application as fast kicker pulse modulators for charged particle beams. The solid state, inductive adder, pulse generator is similar in operation to the linear induction accelerator. The main difference is that the solid state, adder couples energy by transformer action from multiple primaries to a voltage summing stalk, instead of an electron beam. Ideally, the inductive adder produces a rectangular voltage pulse at the load. In reality, there is usually some voltage variation at the load due to droop on primary circuit storage capacitors, or, temporal variations in the load impedance. Power MOSFET circuits have been developed to provide analog modulation of the output voltage amplitude of a solid state, inductive adder, pulse generator. The modulation is achieved by including MOSFET based, variable subtraction circuits in the multiple primary stack. The subtraction circuits can be used to compensate for voltage droop, or, to tailor the output pulse amplitude to provide a desired effect in the load. Power MOSFET subtraction circuits have been developed to modulate short, temporal (60-400 ns), voltage and current pulses. MOSFET devices have been tested up to 20 amps and 800 Volts with a band pass …
Date: June 24, 2002
Creator: Gower, E J & Sullivan, J S
System: The UNT Digital Library
Analysis of Beam Induced Pressure Increases in Rhic Warm Vacuum Sections. (open access)

Analysis of Beam Induced Pressure Increases in Rhic Warm Vacuum Sections.

With increasing intensity of gold and proton beams during recent RHIC operations, pressure rises of several decades were observed at a few RHIC warm vacuum sections. The pressure increases were analyzed and compared with the beam parameters such as ion species, bunch intensity, total intensity, number ofbunches, bunch spacing and beam loss. Most of these pressure increases were found to be consistent with those induced by either beam loss and/or electron multipacting.
Date: June 2, 2002
Creator: Hseuh, H. C.; Smart, L. A. & Zhang, S. Y.
System: The UNT Digital Library
Analysis of thermal-hydrologic-mechanical behavior near an emplacement drift at Yucca Mountain (open access)

Analysis of thermal-hydrologic-mechanical behavior near an emplacement drift at Yucca Mountain

A coupled thermal, hydrologic and mechanical (THM) analysis is conducted to evaluate the impact of coupled THM processes on the performance of a potential nuclear waste repository at Yucca Mountain, Nevada. The analysis considers changes in rock mass porosity, permeability, and capillary pressure caused by rock deformations during drift excavation, as well as those caused by thermo-mechanically induced rock deformations after emplacement of the heat-generating waste. The analysis consists of a detailed calibration of coupled hydraulic-mechanical rock mass properties against field experiments, followed by a prediction of the coupled thermal, hydrologic, and mechanical behavior around a potential repository drift. For the particular problem studied and parameters used, the analysis indicates that the stress-induced permeability changes will be within one order of magnitude and that these permeability changes do not significantly impact the overall flow pattern around the repository drift.
Date: June 17, 2002
Creator: Rutqvist, Jonny & Tsang, Chin-Fu
System: The UNT Digital Library
Application of UAL to High Intensity Beam Dynamics Studies in the SNS Accumulator Ring (open access)

Application of UAL to High Intensity Beam Dynamics Studies in the SNS Accumulator Ring

The SNS Ring off-line parallel simulation environment based on the Unified Accelerator Libraries (UAL) has been implemented and used for extensive full-scale beam dynamics studies arising in high-intensity rings. The paper describes the structure of this environment and its application to the development and analysis of the SNS accumulator ring beam loss model including a complex combination of several physical effects.
Date: June 3, 2002
Creator: Malitsky, N.; Fedotov, A. V. & Wei, J.
System: The UNT Digital Library
Assessing Groundwater Model Uncertainty for the Central Nevada Test Area (open access)

Assessing Groundwater Model Uncertainty for the Central Nevada Test Area

The purpose of this study is to quantify the flow and transport model uncertainty for the Central Nevada Test Area (CNTA). Six parameters were identified as uncertain, including the specified head boundary conditions used in the flow model, the spatial distribution of the underlying welded tuff unit, effective porosity, sorption coefficients, matrix diffusion coefficient, and the geochemical release function which describes nuclear glass dissolution. The parameter uncertainty was described by assigning prior statistical distributions for each of these parameters. Standard Monte Carlo techniques were used to sample from the parameter distributions to determine the full prediction uncertainty. Additional analysis is performed to determine the most cost-beneficial characterization activities. The maximum radius of the tritium and strontium-90 contaminant boundary was used as the output metric for evaluation of prediction uncertainty. The results indicate that combining all of the uncertainty in the parameters listed above propagates to a prediction uncertainty in the maximum radius of the contaminant boundary of 234 to 308 m and 234 to 302 m, for tritium and strontium-90, respectively. Although the uncertainty in the input parameters is large, the prediction uncertainty in the contaminant boundary is relatively small. The relatively small prediction uncertainty is primarily due to the …
Date: June 14, 2002
Creator: Pohll, Greg; Pohlmann, Karl; Hassan, Ahmed; Chapman, Jenny & Mihevc, Todd
System: The UNT Digital Library
Assessment of a Particle Bed Based Beam Stop (open access)

Assessment of a Particle Bed Based Beam Stop

Accelerator target/beam stop concepts able to withstand the thermal shock induced by intense, undiluted beams are being assessed in this study. Such conditions normally push target materials beyond their limits leading to limited useful life. A number of ingenious options have been attempted to help reduce the level of stress generated. Attention is paid to a very promising option that calls for a target consisting of a cooled particle bed. In such configuration the ability of the particle bed structure to diffuse and attenuate the generated thermal shock waves is being explored by performing comprehensive dynamic analyses that incorporate anticipated energy depositions, thermal diffusion, and wave propagation and attenuation. Further, options of coolant liquid filling the porous structure of the particle bed, including concerns of pressure drop and heat transfer, are evaluated for maximizing particle yield.
Date: June 3, 2002
Creator: Simos, N.; Ludewig, H.; Montanez, P. & Todosow, M.
System: The UNT Digital Library
Assessment of health benefits from controlling air pollution in Shanghai, China. (open access)

Assessment of health benefits from controlling air pollution in Shanghai, China.

The large urban centers of the industrializing countries of the world are experiencing severe air quality problems as their demands for energy increase faster than their ability to afford strong environmental protection. This situation is particularly true in the fast-growing part of Asia, where coal often provides the fuel for power generation and industrial development and where the transportation sector grows unchecked. This paper describes the development of an integrated assessment of urban air quality and mitigation options for the city of Shanghai, China. First, a sector-specific, gridded inventory of emissions of SO{sub 2}, NO{sub x}, and particulate matter (PM) is developed. PM is divided into three size categories (TSP, PM{sub 10}, and PM{sub 2.5}) and split into carbonaceous and mineral classes. The URBAT model, a non-steady-state Lagrangian puff model, and related techniques are used to determine the spatial distribution of ambient concentrations of primary and secondary pollutant species. Damage functions are developed to determine the effects of these levels on human health in the greater Shanghai area. Two control scenarios are developed (for power generation and industry), and their effects on emissions of each species are estimated. The health benefits of the control measures are determined, and their relative …
Date: June 18, 2002
Creator: Chang, Y.-S.; Streets, D. G.; Tsao, C. L.; Li, J.; Guttikunda, S. & Carmichael, G. R.
System: The UNT Digital Library
Automated nondestructive evaluation method for characterizing ceramic and metallic hot gas filters. (open access)

Automated nondestructive evaluation method for characterizing ceramic and metallic hot gas filters.

In advanced coal-fired power generation, one technology under development to clean up hot gases before their use as fuel for gas turbines is rigid ceramic candle filters. These porous filters are typically 1.5 m long and 60 mm in diameter and are made of various ceramic materials, including clay-bonded SiC. The high costs of downtime in a large utility demands that nondestructive evaluation/characterization (NDE/C) methods be available. At shutdowns, data from such analysis are needed to decide which filters are still usable and which need to be replaced, and if possible, to estimate the remaining lifetimes. Thus our objective was to develop reliable low-cost NDE technology for these filters. Our approach was to develop NDE/C technology, referred to as acousto-ultrasonics (AU), for application to hot gas filters. Lamb waves generated by the AU method were analyzed to derive a stress wave factor (SWF). This technology was tested by comparing SWF data with the measured strength for a variety of rigid ceramic filters and was shown to work on iron-aluminide filters as well but no strength data have been obtained on the iron-aluminides at this time.
Date: June 3, 2002
Creator: Ellingson, W. A.; Koehl, E. R.; Deemer, C.; Pastilla, P.; Wheeler, B. & Forster, G. A.
System: The UNT Digital Library
Autophosphorylation of the DNA-Dependent Protein Kinase Catalyticsubunit is Required for Rejoining of DNA Double-Strand Breaks (open access)

Autophosphorylation of the DNA-Dependent Protein Kinase Catalyticsubunit is Required for Rejoining of DNA Double-Strand Breaks

This report is a descriptive journey of the Autophosphorylation of the DNA-Dependent Protein Kinase Catalyticsubunit is Required for Rejoining of DNA Double-Strand Breaks.
Date: June 5, 2002
Creator: Chan, Doug W.; Chen, Benjamin Ping-Chi; Yang, Shun-Jen; Singh,Sheela; Murphy, Michael B.; Kurimasa, Akihiro et al.
System: The UNT Digital Library
S-Band High Duty Photo-Injection System. (open access)

S-Band High Duty Photo-Injection System.

None
Date: June 3, 2002
Creator: Wang, X. J.; Babzien, M.; Chang, X. Y.; Lynch, D.; Pjerov, S.; Woodle, M. et al.
System: The UNT Digital Library