Correction of dispersion and the betatron functions in the CEBAF accelerator (open access)

Correction of dispersion and the betatron functions in the CEBAF accelerator

During the commissioning of the CEBAF accelerator, correction of dispersion and momentum compaction, and, to a lesser extent, transverse transfer matrices were essential for robust operation. With changing machine conditions, repeated correction was found necessary. To speed the diagnostic process the authors developed a method which allows one to rapidly track the machine optics. The method is based on measuring the propagation of 30 Hz modulated betatron oscillations downstream of a point of perturbation. Compared to the usual methods of dispersion or difference orbit measurement, synchronous detection of the beam displacement, as measured by beam position monitors, offers significantly improved speed and accuracy of the measurements. The beam optics of the accelerator was altered to decrease lattice sensitivity at critical points and to simplify control of the betatron function match. The calculation of the Courant-Snyder invariant from signals of each pair of nearby beam position monitors has allowed one to perform on-line measurement and correction of the lattice properties.
Date: October 1, 1996
Creator: Lebedev, V. A.; Bickley, M.; Schaffner, S.; Zeijts, J. van; Krafft, G. A. & Watson, C.
Object Type: Report
System: The UNT Digital Library
Space-charge-dominated beam dynamics simulations using the massively parallel processors (MPPs) of the Cray T3D (open access)

Space-charge-dominated beam dynamics simulations using the massively parallel processors (MPPs) of the Cray T3D

Computer simulations using the multi-particle code PARMELA with a three-dimensional point-by-point space charge algorithm have turned out to be very helpful in supporting injector commissioning and operations at Thomas Jefferson National Accelerator Facility (Jefferson Lab, formerly called CEBAF). However, this algorithm, which defines a typical N{sup 2} problem in CPU time scaling, is very time-consuming when N, the number of macro-particles, is large. Therefore, it is attractive to use massively parallel processors (MPPs) to speed up the simulations. Motivated by this, the authors modified the space charge subroutine for using the MPPs of the Cray T3D. The techniques used to parallelize and optimize the code on the T3D are discussed in this paper. The performance of the code on the T3D is examined in comparison with a Parallel Vector Processing supercomputer of the Cray C90 and an HP 735/15 high-end workstation.
Date: October 1, 1996
Creator: Liu, H.
Object Type: Report
System: The UNT Digital Library
D0 Silicon Upgrade: Redesign of the Low Conductivity Water (LCW) System at D-Zero (open access)

D0 Silicon Upgrade: Redesign of the Low Conductivity Water (LCW) System at D-Zero

Due to the relocation of a magnet power supply, the installation of a buss, and an installation of chokes. and their need for cooling water a redesign of the Low Conductivity Water (LCW) system has been undertaken. This new system required the determination of an optimal pipe diameter for the High Bay pipe as well as the determination of the pressure drop and temperature rise in the buss. Based on numerous calculations it has been determined that the High Bay pipe should be 1 1/2 inch (1.90 O.D. x 1.610 I.D-40S steel). While the pressure drop in the buss was calculated to be 7.699 psi. Based on such a low pressure drop, no need for any additional pumps has presented itself. Finally, the temperature rise in the buss has been determined to be about 29.39 F for the Assembly Hall (route No.1). and 13.93 F for the Collision Hall (route No.2). The purpose of this engineering note is to explain the redesign of the low conductivity water system (LCW) at D-Zero. The areas to be covered include the sizing of the High Bay, the pressure drop and temperature rise in the buss. In addition, I will try to determine if …
Date: October 15, 1996
Creator: Zaczek, Mariusz
Object Type: Report
System: The UNT Digital Library
Electric Industry Restructuring in Five States: Final Report (open access)

Electric Industry Restructuring in Five States: Final Report

The electric industry in the United States is undergoing fundamental changes; it is transitioning from regulated monopolies to competitive markets offering customer choice. In this process, the states have been in the forefront of considering the changes in the industry structure and regulation. The Energy Information Administration (EIA) spearheaded a project on electric restructuring in the United States. This is the final report prepared under the project. The purpose of the report is to describe and compare the overall restructuring processes that took place in five states through June 30, 1996. The five states are California, Massachusetts, Michigan, New York, and Wisconsin. These are the first major states to consider restructuring or retail wheeling.
Date: October 31, 1996
Creator: Fang, J. M.
Object Type: Report
System: The UNT Digital Library
Measurement of the Angular Distribution of the Electron From W {r_arrow} E = {Nu} decay, in P{Anti P} at {Radical}S = 1.8 Tev, as Function of P{Sub T}{Sup W}; Medida De La Distribucion Angular Del Electron De W en E + Neutrino en P{Anti P} a 1.8 Tev (open access)

Measurement of the Angular Distribution of the Electron From W {r_arrow} E = {Nu} decay, in P{Anti P} at {Radical}S = 1.8 Tev, as Function of P{Sub T}{Sup W}; Medida De La Distribucion Angular Del Electron De W en E + Neutrino en P{Anti P} a 1.8 Tev

The goal of this work was to study the behavior of the angular distribution of the electron form the decay of the W boson in a specific rest-frame of the W, the Collins-Soper frame. This thesis consists of four major divisions, each dealing with closely related themes: (a) Physics Background, (b) Description of the Hardware and General Software Tools, (c) Description of the Analysis and Specific Tools, and (d) Results and Conclusions. Each division is comprised of one or more chapters and each chapter is divided into sections and subsections.
Date: October 7, 1996
Creator: Ramos, M. I. M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Jefferson Lab, a status report (open access)

Jefferson Lab, a status report

Thomas Jefferson National Accelerator Facility (Jefferson Lab; formerly known as CEBAF), operates a 4 GeV, 200 {micro}A continuous wave (CW) electron accelerator that re-circulates the beam five times through two superconducting 400 MeV linacs. Electrons can be extracted from any of the five recirculation passes and beam can be simultaneously delivered to the three experimental halls. As the commissioning stage nears completion, the accelerator is becoming a fully operational machine. Experiments in Hall C have been underway since November 1995 with beam powers of over 300 kW at various energies. Hall A has received beam for spectrometer commissioning, while Hall B is expected to receive its first beam in the fall of 1996. Accelerator availability of greater than 70% during physics runs and excellent beam quality have contributed to making Jefferson Lab a world class laboratory for accelerator-based electromagnetic nuclear physics. With the high performance of the superconducting RF cavities, machine upgrades to 6 GeV, and eventually 8 to 10 GeV are now in the planning stages. Operational and commissioning details concerning all aspects of the machine will be discussed.
Date: October 1, 1996
Creator: Dunham, B. M.
Object Type: Report
System: The UNT Digital Library
QA CLASSIFICATION ANALYSIS OF GROUND SUPPORT SYSTEMS (open access)

QA CLASSIFICATION ANALYSIS OF GROUND SUPPORT SYSTEMS

The purpose and objective of this analysis is to determine if the permanent function Ground Support Systems (CI: BABEEOOOO) are quality-affecting items and if so, to establish the appropriate Quality Assurance (QA) classification.
Date: October 29, 1996
Creator: Gwyn, D. W.
Object Type: Report
System: The UNT Digital Library
Next Generation Geothermal Power Plants (NGGPP) process data for binary cycle plants (open access)

Next Generation Geothermal Power Plants (NGGPP) process data for binary cycle plants

The Next Generation Geothermal Power Plants (NGGPP) study provides the firm estimates - in the public domain - of the cost and performance of U.S. geothermal systems and their main components in the early 1990s. The study was funded by the U.S. Department of Energy Geothermal Research Program, managed for DOE by Evan Hughes of the Electric Power Research Institute, Palo Alto, CA, and conducted by John Brugman and others of the CE Holt Consulting Firm, Pasadena, CA. The printed NGGPP reports contain detailed data on the cost and performance for the flash steam cycles that were characterized, but not for the binary cycles. The nine Tables in this document are the detailed data sheets on cost and performance for the air cooled binary systems that were studied in the NGGPP.
Date: October 2, 1996
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Electrochemical Aging of Thermal-Sprayed Zinc Anodes on Concrete (open access)

Electrochemical Aging of Thermal-Sprayed Zinc Anodes on Concrete

Thermal-sprayed zinc anodes are used in impressed current cathodic protection systems for some of Oregon's coastal reinforced concrete bridges. Electrochemical aging of zinc anodes results in physical and chemical changes at the zinc-concrete interface. Concrete surfaces heated prior to thermal-spraying had initial adhesion strengths 80 pct higher than unheated surfaces. For electrochemical aging greater than 200 kC/m{sup 2} (5.2 A h/ft{sup 2}), there was no difference in adhesion strengths for zinc on preheated and unheated concrete. Adhesion strengths decreased monotonically after about 400 to 600 kC/m{sup 2} (10.4 to 15.6 A-h/ft{sup 2}) as a result of the reaction zones at the zinc-concrete interface. A zone adjacent to the metallic zinc (and originally part of the zinc coating) was primarily zincite (ZnO), with minor constituents of wulfingite (Zn(OH){sub 2}), simonkolleite (Zn{sub 5}(OH) {sub 8}C{sub l2}{sup .}H{sub 2}O), and hydrated zinc hydroxide sulfates (Zn{sub 4}SO{sub 4}(OH){sub 6}{sup .}xH{sub 2}O). This zone is the locus for cohesive fracture when the zinc coating separates from the concrete during adhesion tests. Zinc ions substitute for calcium in the cement paste adjacent to the coating as the result of secondary mineralization. The initial estimate of the coating service life based on adhesion strength measurements in accelerated …
Date: October 1996
Creator: Holcomb, G. R.; Bullard, S. J.; Covino, B. S., Jr.; Cramer, S. D.; Cryer, C. B. & McGill, G. E.
Object Type: Article
System: The UNT Digital Library
FINITE-ELEMENT ANALYSIS OF ROCK FALL ON UNCANISTERED FUEL WASTE PACKAGE DESIGNS (SCPB: N/A) (open access)

FINITE-ELEMENT ANALYSIS OF ROCK FALL ON UNCANISTERED FUEL WASTE PACKAGE DESIGNS (SCPB: N/A)

The objective of this analysis is to explore the Uncanistered Fuel (UCF) Tube Design waste package (WP) resistance to rock falls. This analysis will also be used to determine the size of rock that can strike the WP without causing failure in the containment barriers from a height based on the starter tunnel dimensions. The purpose of this analysis is to document the models and methods used in the calculations.
Date: October 18, 1996
Creator: Ceylan, Z.
Object Type: Report
System: The UNT Digital Library
WESTINGHOUSE 17X17 MOX PWR ASSEMBLY - WASTE PACKAGE STRUCTURAL ANALYSIS (open access)

WESTINGHOUSE 17X17 MOX PWR ASSEMBLY - WASTE PACKAGE STRUCTURAL ANALYSIS

The objective of this analysis is to explore the Westinghouse mixed-oxide (MOX) and Combustion Engineering MOX assembly waste package (WP) resistance to rock fall, slap-down, and two meter drop events. This analysis will be used to evaluate the structural performance of the waste packages. The purpose of this analysis is to document the models and methods used in the calculations. The results of this analysis are not intended to show direct compliance with any design requirements.
Date: October 17, 1996
Creator: Ceylan, Z.
Object Type: Report
System: The UNT Digital Library
Control of Trace Metal Emissions During Coal Combustion (open access)

Control of Trace Metal Emissions During Coal Combustion

Emissions of toxic trace metals in the form of metal fumes or submicron particulate from a coal-fired combustion source have received greater environmental and regulatory concern over the past years. Current practice of controlling these emissions is to collect them at the cold-end of the process by air-pollution control devices (APCDS) such as electrostatic precipitators and baghouses. However, trace metal fumes may not always be effectively collected by these devices because the formed fumes are extremely small. The proposed research is to explore the opportunities for improved control of toxic trace metal emissions, alternatively, at the hot-end of the coal combustion process, i.e., in the combustion chamber. The technology proposed is to prevent the metal fumes from forming during the process, which would effectively eliminate the metal emission problems. Specifically, the technology is to employ suitable sorbents to (1) reduce the amount of metal volatilization during combustion and (2) capture volatilized metal vapors. The objectives of the project are to demonstrate the technology and to characterize the metal capture process during coal combustion in a fluidized bed combustor.
Date: October 1, 1996
Creator: Ho, Thomas C.
Object Type: Report
System: The UNT Digital Library
Preparation of ultralow-friction surface films on vanadium diboride. (open access)

Preparation of ultralow-friction surface films on vanadium diboride.

In this paper, we present a simple annealing procedure (which we refer to as ''flash-annealing'' because of short duration) that results in the formation of an ultralow friction surface film on vanadium diboride (VB{sub 2}) surfaces. This annealing is done in a box furnace at 800 C for a period of 5 min. During annealing, the exposed surface of the VB{sub 2} undergoes oxidation and forms a layer of boron oxide (B{sub 2}O{sub 3}). In open air, the B{sub 2}O{sub 3} layer reacts spontaneously with moisture and forms a boric acid (H{sub 3}BO{sub 3}) film. The friction coefficient of a 440C steel pin against this H{sub 3}BO{sub 3} film is {approx}0.05, compared to 0.8 against the as-received VB{sub 2}. Based on Raman spectroscopy and electron microscopy studies, we elucidate the ultralow friction mechanism of the flash-annealed VB{sub 2} surfaces.
Date: October 14, 1996
Creator: Erdemir, A.; Fenske, G. R. & Halter, M.
Object Type: Article
System: The UNT Digital Library
Bioremediation Techniques of Oil Contaminated Soils in Ohio (open access)

Bioremediation Techniques of Oil Contaminated Soils in Ohio

The objective of this project is to develop environmentally sound and cost-effective remediation techniques for crude oil contaminated soils. By providing a guidance manual to oil and gas operators, the Ohio Division of Oil and Gas regulatory authority hopes to reduce remediation costs while improving voluntary compliance with soil clean-up requirements. This shall be accomplished by conducting a series of field tests to define the optimum range for nutrient and organic enhancement to biologically remediate soils contaminated with brines and crude oil having a wide rage of viscosity.
Date: October 3, 1996
Creator: Hodges, David
Object Type: Report
System: The UNT Digital Library
Application of Catalytic Extraction Processing to DOE Wastes (open access)

Application of Catalytic Extraction Processing to DOE Wastes

None
Date: October 1, 1996
Creator: unknown
Object Type: Article
System: The UNT Digital Library
Scale-Up of Advanced Hot-Gas Desulfurization Sorbents (open access)

Scale-Up of Advanced Hot-Gas Desulfurization Sorbents

The overall objective of this project is to develop regenerable sorbents for hot gas desulfurization in IGCC systems. The specific objective of the project is to develop durable advanced sorbents that demonstrate a strong resistance to attrition and chemical deactivation, and high activity at temperatures as low as 343 C (650 F). A number of formulations will be prepared and screened in a 1/2-inch fixed bed reactor at high pressure (1 to 20 atm) and high temperatures using simulated coal-derived fuel-gases. Screening criteria will include, chemical reactivity, stability, and regenerability over the temperature range of 343 C to 650 C. After initial screening, at least 3 promising formulations will be tested for 25-30 cycles of absorption and regeneration. One of the superior formulations with the best cyclic performance will be selected for investigating scale up parameters. The scaled-up formulation will be tested for long term durability and chemical reactivity.
Date: October 14, 1996
Creator: Jothimurugesan, K. & Gangwal, Santosh K.
Object Type: Report
System: The UNT Digital Library
Fast Wave Heating and Current Drive in DIII-D Discharges With Negative Central Shear (open access)

Fast Wave Heating and Current Drive in DIII-D Discharges With Negative Central Shear

The noninductive current driven by fast Alfven waves (FWCD) has been applied to discharges in DIII-D with negative central shear. Driven currents as high as 275 kA have been achieved with up to 3 MW of fast wave power with the efficiency and profile as predicted by theory-based modeling. When counter-current FWCD was applied to discharges with negative central shear, the negative shear was strengthened and prolonged, showing that FWCD can help to control the current profile in advanced tokamak discharges. Under some conditions in negative central shear, the plasma spontaneously makes a transition into a regime of improved performance, with a reduction in both the ion and the electron heat diffusivities. Up to 3 MW of fast wave power has been successfully coupled into H-mode discharges with large edge localized modes through use of an innovative decoupler/hybrid power splitter combination.
Date: October 1, 1996
Creator: Prater, R.; Austin, M. E. & Baity, F. W.
Object Type: Article
System: The UNT Digital Library
Mixed Waste Focus Area Program Management Plan (open access)

Mixed Waste Focus Area Program Management Plan

This plan describes the program management principles and functions to be implemented in the Mixed Waste Focus Area (MWFA). The mission of the MWFA is to provide acceptable technologies that enable implementation of mixed waste treatment systems developed in partnership with end-users, stakeholders, tribal governments and regulators. The MWFA will develop, demonstrate and deliver implementable technologies for treatment of mixed waste within the DOE Complex. Treatment refers to all post waste-generation activities including sampling and analysis, characterization, storage, processing, packaging, transportation and disposal.
Date: October 1, 1996
Creator: Beitel, G. A.
Object Type: Report
System: The UNT Digital Library
Gene identification and analysis: an application of neural network-based information fusion (open access)

Gene identification and analysis: an application of neural network-based information fusion

Identifying genes within large regions of uncharacterized DNA is a difficult undertaking and is currently the focus of many research efforts. We describe a gene localization and modeling system called GRAIL. GRAIL is a multiple sensor-neural network based system. It localizes genes in anonymous DNA sequence by recognizing gene features related to protein-coding slice sites, and then combines the recognized features using a neural network system. Localized coding regions are then optimally parsed into a gene mode. RNA polymerase II promoters can also be predicted. Through years of extensive testing, GRAIL consistently localizes about 90 percent of coding portions of test genes with a false positive rate of about 10 percent. A number of genes for major genetic diseases have been located through the use of GRAIL, and over 1000 research laboratories worldwide use GRAIL on regular bases for localization of genes on their newly sequenced DNA.
Date: October 1, 1996
Creator: Matis, Sherri; Xu, Ying; Shah, Manesh B.; Mural, Richard J.; Einstein, J. R. & Uberbacher, Edward C.
Object Type: Report
System: The UNT Digital Library
Stability of purgeable VOCs in water samples during pre-analytical holding: Part 1, Analysis by a commercial laboratory (open access)

Stability of purgeable VOCs in water samples during pre-analytical holding: Part 1, Analysis by a commercial laboratory

This study was undertaken to examine the hypothesis that prevalent and priority purgeable VOCs in properly preserved water samples are stable for at least 28 days. (VOCs are considered stable if concentrations do not change by more than 10%.) Surface water was spiked with 44 purgeable VOCs. Results showed that the measurement of 35 out of 44 purgeable VOCs in properly preserved water samples (4 C, 250 mg NaHSO{sub 4}, no headspace in 40 mL VOC vials with 0.010-in. Teflon-lined silicone septum caps) will not be affected by sample storage for 28 days. Larger changes (>10%) and low practical reporting times were observed for a few analytes, e.g. acrolein, CS{sub 2}, vinyl acetate, etc.; these also involve other analytical problems. Advantages of a 28-day (compared to 14-day) holding time are pointed out.
Date: October 1, 1996
Creator: West, Olivia R.; Bayne, Charles K.; Siegrist, Robert L.; Holden, William L.; Scarborough, Shirley S. & Bottrell, David W.
Object Type: Report
System: The UNT Digital Library
NIF pointing and centering systems and target alignment using a 351 nm laser source (open access)

NIF pointing and centering systems and target alignment using a 351 nm laser source

The operational requirements of the National Ignition Facility (NIF) place tight constraints upon its alignment system. In general, the alignment system must establish and maintain the correct relationships between beam position, beam angle, laser component clear apertures, and the target. At the target, this includes adjustment of beam focus to obtain the correct spot size. This must be accomplished for all beamlines in a time consistent with planned shot rates and yet, in the front end and main laser, beam control functions cannot be initiated until the amplifiers have sufficiently cooled so as to minimize dynamic thermal distortions during and after alignment and wavefront optimization. The scope of the task dictates an automated system that implements parallel processes. We describe reticle choices and other alignment references, insertion of alignment beams, principles of operation of the Chamber Center Reference System 2048 and Target Alignment Sensor, and the anticipated alignment sequence that will occur between shots.
Date: October 1, 1996
Creator: Boege, Steven J.; Bliss, Erlan S.; Chocol, Clifford J.; Holdener, Fred R.; Miller, John L.; Toeppen, John S. et al.
Object Type: Article
System: The UNT Digital Library
Trial application of a technique for human error analysis (ATHEANA) (open access)

Trial application of a technique for human error analysis (ATHEANA)

The new method for HRA, ATHEANA, has been developed based on a study of the operating history of serious accidents and an understanding of the reasons why people make errors. Previous publications associated with the project have dealt with the theoretical framework under which errors occur and the retrospective analysis of operational events. This is the first attempt to use ATHEANA in a prospective way, to select and evaluate human errors within the PSA context.
Date: October 1, 1996
Creator: Bley, Dennis C.; Cooper, Susan E.; Parry, Gareth W.; Wreathall, John; Luckas, William J.; Drouin, Mary et al.
Object Type: Article
System: The UNT Digital Library
Using final state gluons as probes of anomalous top quark couplings at the NLC (open access)

Using final state gluons as probes of anomalous top quark couplings at the NLC

The rate and corresponding gluon jet energy distribution for the process e{sup +}e{sup {minus}} {r_arrow} t{anti t}g are sensitive to the presence of anomalous dipole-like couplings of the top to the photon and Z at the production vertex as well as to the gluon itself. For sizeable anomalous couplings substantial derivations in the shape and magnitude of the gluon spectrum from the expectations of the Standard Model are anticipated. The authors explore the capability of the Next Linear Collider to either discover or place bounds on these types of top quark couplings through measurements of the gluon energy distribution. The resulting constraints are found to be quite complementary to those obtained using other techniques.
Date: October 1, 1996
Creator: Rizzo, Thomas G.
Object Type: Article
System: The UNT Digital Library
Recent trends in inorganic mass spectrometry (open access)

Recent trends in inorganic mass spectrometry

The field of inorganic mass spectrometry has seen substantial change in the author`s professional lifetime (over 30 years). Techniques in their infancy 30 years ago have matured; some have almost disappeared. New and previously unthought of techniques have come into being; some of these, such as ICP-MS, are reasonably mature now, while others have some distance to go before they can be so considered. Most of these new areas provide fertile fields for researchers, both in the development of new analytical techniques and by allowing fundamental studies to be undertaken that were previously difficult, impossible, or completely unforeseen. As full coverage of the field is manifestly impossible within the framework of this paper, only those areas with which the author has personal contact will be discussed. Most of the work originated in his own laboratory, but that of other laboratories is covered where it seemed appropriate.
Date: October 1, 1996
Creator: Smith, D. H.; Barshick, C. M.; Duckworth, D. C. & Riciputi, L. R.
Object Type: Article
System: The UNT Digital Library