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Operation and tests of a DDC101 A/D (open access)

Operation and tests of a DDC101 A/D

For the KTeV PMT laser monitoring system, one needs a high resolution device with a large dynamic range to be used for digitizing PIN photodiodes. The dynamic range should be wider than or comparable to the KTeV digitizer (17-bits). The Burr-Brown DDC101 is a precision, wide dynamic range, charge digitizing A/D converter with 20-bit resolution, packaged in a 28-pin plastic, double-wide DP. Low level current output devices, such as photosensors can be directly connected to its input. The digital output can be clocked-out serially from the pins. For typical operations, a relatively wide gate of 1 msec should be used. The full scale charge is 500 pC for unipolar mode. The bipolar mode scale is {+-} 250 pC. The advertised integral nonlinearity is 0.003% of FSR. This document describes only the basic DDC101 operations since full detail can be found in the DDC101 manual. Tests results are given in section 3.
Date: November 1, 1994
Creator: Nguyen, H.
Object Type: Report
System: The UNT Digital Library
Mass transport through polycrystalline microstructures (open access)

Mass transport through polycrystalline microstructures

Mass transport properties are important in polycrystalline materials used as protective films. Traditionally, such properties have been studied by examining model polycrystalline structures, such as a regular array of straight grain boundaries. However, these models do not account for a number of features of real grain ensembles, including the grain size distribution and variations in grain shape. In this study, a finite difference scheme is developed to study transient and steady-state mass transport through realistic two dimensional polycrystalline microstructures. Comparisons with the transport properties of traditional model microstructures provide regimes of applicability of such models. The effects of microstructural parameters such as average grain size are examined.
Date: December 31, 1994
Creator: Swiler, T. P.; Holm, E. A.; Young, M. F. & Wright, S. A.
Object Type: Report
System: The UNT Digital Library
Using and programming the SUPERCODE (open access)

Using and programming the SUPERCODE

SUPERCODE is a systems code used in designing tokamak devices and reactors. This report is divided into 4 chapters. Chapter one covers installing the code and directory organization. The execution of the code, command line editing and history, the shell language, classes, and shell input and output are discussed in chapter two. Chapter three covers the writing modules. In chapter four, the Consts module, Sys module, and Plot module are covered. At the end of the report, the need and use of SUPERCODE are summarized.
Date: June 8, 1994
Creator: Haney, S. W.
Object Type: Report
System: The UNT Digital Library
The railplug: Development of a new ignitor for internal combustion engines. Final report (open access)

The railplug: Development of a new ignitor for internal combustion engines. Final report

A three year investigation of a new type of ignitor for internal combustion engines has been performed using funds from the Advanced Energy Projects Program of The Basic Energy Sciences Division of the U.S. Department of Energy and with matching funding from Research Applications, Inc. This project was a spin-off of {open_quotes}Star Wars{close_quotes} defense technology, specifically the railgun. The {open_quotes}railplug{close_quotes} is a miniaturized railgun which produces a high velocity plume of plasma that is injected into the combustion chamber of an engine. Unlike other types of alternative ignitors, such as plasma jet ignitors, electromagnetic forces enhance the acceleration of the plasma generated by a railplug. Thus, for a railplug, the combined effects of electromagnetic and thermodynamic forces drive the plasma into the combustion chamber. Several engine operating conditions or configurations can be identified that traditionally present ignition problems, and might benefit from enhanced ignition systems. One of these is ultra-lean combustion in spark ignition (SI) engines. This concept has the potential for lowering emissions of NOx while simultaneously improving thermal efficiency. Unfortunately, current lean burn engines cannot be operated sufficiently lean before ignition related problems are encountered to offer any benefits. High EGR engines have similar potential for emissions improvement, …
Date: November 29, 1994
Creator: Matthews, R. D.; Nichols, S. P. & Weldon, W. F.
Object Type: Report
System: The UNT Digital Library
A Simple, Closed-Form Expression for the X-Ray Reflectivity From Superlattices With Cumulative Roughness (open access)

A Simple, Closed-Form Expression for the X-Ray Reflectivity From Superlattices With Cumulative Roughness

The authors present a simple closed-form expression for the reflectivity from a multilayer which includes the effects of absorption, refraction, surface and substrate reflections but neglects dynamical effects. This expression reproduces the exact dynamical calculation except for the regions near the critical angle and for intense Bragg reflections. The expression is generalized to include cumulative interface roughness which follows a t{sup 1/2} power-law growth.
Date: May 1, 1994
Creator: Kelly, D. M.; Santa-Maria, J.; Schuller, I. K. & Fullerton, E. E.
Object Type: Report
System: The UNT Digital Library
Further studies of the effects of oxidation on the surface properties of coal and coal pyrite (open access)

Further studies of the effects of oxidation on the surface properties of coal and coal pyrite

The objective of this research was to investigate the oxidation behavior of coal and coal pyrite and to correlate the changes in the surface properties induced by oxidation, along with the intrinsic physical and chemical properties of these organic and inorganic materials, with the behavior in physical coal cleaning processes. This provide more fundamental knowledge for understanding the way in which different factors interact in a medium as heterogeneous as coal. Fourteen coal samples of different ranks ranging from high to medium sulfur content were studied by dry oxidation tests at different temperatures and humidities, and by wet oxidation tests using different oxidizing agents. The concentration of surface oxygen functional groups was determined by ion-exchange methods. The changes in the coal composition with oxidation were analyzed by spectroscopic techniques. The wettability of as-received and oxidized coal and coal pyrite samples was assessed by film flotation tests. The electrokinetic behavior of different coals and coal pyrite samples was studied by electrokinetic tests using electrophoresis. Possible oxidation mechanisms have been proposed to explain the changes on the coal surface induced by different oxidation treatments.
Date: December 31, 1994
Creator: Herrera, Miguel Nicholas
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Measurement of {alpha}{sub s} from hadronic event observables at the Z{sup 0} resonance (open access)

Measurement of {alpha}{sub s} from hadronic event observables at the Z{sup 0} resonance

The authors have measured the strong coupling {alpha}{sub s} using hadronic decays of Z{sup 0} bosons collected by the SLD experiment at SLAC. The data were compared with QCD predictions both at fixed order, O({alpha}{sub s}{sup 2}), and including resummed analytic formulae based on the leading and next-to-leading logarithm approximation. The study includes event shapes, jet rates, and particle correlations. They checked the consistency between {alpha}{sub s} extracted from these different measures and found the dominant uncertainty on {alpha}{sub s} to be from uncalculated higher order contributions.
Date: August 1, 1994
Creator: Ohnishi, Yukiyoshi
Object Type: Article
System: The UNT Digital Library
Effect of glass composition on waste form durability: A critical review (open access)

Effect of glass composition on waste form durability: A critical review

This report reviews literature concerning the relationship between the composition and durability of silicate glasses, particularly glasses proposed for immobilization of radioactive waste. Standard procedures used to perform durability tests are reviewed. It is shown that tests in which a low-surface area sample is brought into contact with a very large volume of solution provide the most accurate measure of the intrinsic durability of a glass composition, whereas high-surface area/low-solution volume tests are a better measure of the response of a glass to changes in solution chemistry induced by a buildup of glass corrosion products. The structural chemistry of silicate and borosilicate glasses is reviewed to identify those components with the strongest cation-anion bonds. A number of examples are discussed in which two or more cations engage in mutual bonding interactions that result in minima or maxima in the rheologic and thermodynamic properties of the glasses at or near particular optimal compositions. It is shown that in simple glass-forming systems such interactions generally enhance the durability of glasses. Moreover, it is shown that experimental results obtained for simple systems can be used to account for durability rankings of much more complex waste glass compositions. Models that purport to predict the …
Date: November 1, 1994
Creator: Ellison, A. J. G.; Mazer, J. J. & Ebert, W. L.
Object Type: Report
System: The UNT Digital Library
The development of mechanical strength in a ceramic material during firing (open access)

The development of mechanical strength in a ceramic material during firing

This experiment was designed for high school students who have a very limited background in ceramic materials, but the experiments could also be used at the college level. The objective of the experiment is to teach students about the development of mechanical strength in a ceramic material as a result of the firing process and about testing methods used for brittle materials. In the experiment, clay-based ceramic bars of uniform circular cross section are prepared by extrusion. The bars are then fired at temperatures high enough to achieve high strength by development of a glassy bonding phase. Finally, the bars will be stressed to failure in a simple testing machine. This will quantify the increase in strength as a function of firing temperature.
Date: November 1, 1994
Creator: Bunnell, L. R. & Piippo, S. W.
Object Type: Article
System: The UNT Digital Library
Waste minimization at Lawrence Livermore National Laboratory: A case study of environmentally conscious manufacturing (open access)

Waste minimization at Lawrence Livermore National Laboratory: A case study of environmentally conscious manufacturing

The purpose of this paper is to provide an update on what we`ve accomplished and have planned in our plating operation at Lawrence Livermore National Laboratory (LLNL) in the area of waste minimization. Our efforts have included issues other than waste minimization and, therefore, fall under the wider umbrella entitled pollution prevention or environmentally conscious electroplating. Approximately one year has passed since our last report on pollution prevention and since this topic remains a high-effort activity much more has been accomplished. Our efforts to date fall under the first two generation categories of waste reduction. Good housekeeping practices, inventory control, and minor changes in operating practices (first generation) resulted in an impressive amount of waste reduction. In the second generation of waste reduction, current technology, separation technologies, and material substitutions were used to reduce emission and wastes. The third generation of improvements requires significant technological advances in process synthesis and engineering. We are presently starting some projects in this third generation phase and these will be discussed at the end of this paper.
Date: February 1, 1994
Creator: Steffani, C. P. & Dini, J. W.
Object Type: Article
System: The UNT Digital Library
ICRF heating of TFTR deuterium supershot plasmas in the {sup 3}He minority regime (open access)

ICRF heating of TFTR deuterium supershot plasmas in the {sup 3}He minority regime

The increased core electron temperature produced by ICRF heating of TFTR, D-T neutral-beam-heated supershot plasmas is expected to extend the alpha particle slowing down time and hence enhance the central alpha particle pressure. In preparation for the TFTR D-T operational phase, which is due to start in late 1993, a series of experiments were conducted on TFTR to explore the effect of ICRF heating on the performance and stability of low recycling, deuterium supershot plasmas in the {sup 3}He minority heating regime. The coupling of up to 7.4 MW of 47 MHz ICRF power to full size {sup 3}He minority, deuterium supershots heated with up to 30 MW of deuterium neutral beam injection has resulted in a significant increase in core electron temperature. Simulations of equivalent D-T supershots predict that such ICRF heating should result in approximately a 60% increase in the alpha particle slowing down time and an enhancement of about 30% in the central alpha pressure. Future experiments to be conducted at ICRF powers up to 12.5MW during the upcoming TFTR D-T campaign may result in even greater enhancements in core alpha parameters. This paper presents results from experiments performed at an axial toroidal magnetic field of {approximately}4.8T, …
Date: January 1, 1994
Creator: Taylor, G.; Wilson, J. R. & Goldfinger, R. C.
Object Type: Report
System: The UNT Digital Library
Linear non-modal phenomena in numerical analysis and applied mathematics. First annual performance report, February 15, 1994--November 15, 1994 (open access)

Linear non-modal phenomena in numerical analysis and applied mathematics. First annual performance report, February 15, 1994--November 15, 1994

This report contains information on the following topics: pseudospectra of an operator of Hille and Phillips; Schwarz- Christoffel toolbox user`s guide; a matlab toolbox for Schwarz- Christoffel mapping; spectra and pseudospectra for pipe poiseuille flow; faster SVD for matrices with small m/n; calculation of pseudospectra by the Arnoldi iteration; and mostly linear model of transition to turbulence.
Date: November 14, 1994
Creator: Trefethen, L. N.
Object Type: Report
System: The UNT Digital Library
A summary of the report on prospects for pyrolysis technologies in managing municipal, industrial, and Department of Energy cleanup wastes (open access)

A summary of the report on prospects for pyrolysis technologies in managing municipal, industrial, and Department of Energy cleanup wastes

Pyrolysis converts portions of municipal solid wastes, hazardous wastes and special wastes such as tires, medical wastes and even old landfills into solid carbon and a liquid or gaseous hydrocarbon stream. In the past twenty years, advances in the engineering of pyrolysis systems and in sorting and feeding technologies for solid waste industries have ensured consistent feedstocks and system performance. Some vendors now offer complete pyrolysis systems with performance warranties. This report analyzes the potential applications of pyrolysis in the Long Island region and evaluates the four most promising pyrolytic systems for their readiness, applicability to regional waste management needs and conformity with DOE environmental restoration and waste management requirements. This summary characterizes the engineering performance, environmental effects, costs, product applications and markets for these pyrolysis systems.
Date: August 1, 1994
Creator: Reaven, S. J.
Object Type: Report
System: The UNT Digital Library
Geophysical investigation for proposed flow meter installation holes, 100H Area (open access)

Geophysical investigation for proposed flow meter installation holes, 100H Area

The objectives of the surveys were to locate subsurface obstructions that may affect the drilling of two holes to be fit with flow meters in the 100-H Area of the Hanford Site (Figure 1). Possible drill sites with the least likelihood of encountering identified obstructions were identified based upon the results of the survey. Ground-penetrating radar (GPR) was the method selected for the investigations. The electromagnetic induction method was also used to verify that the general site is relatively void of metallic debris at depth.
Date: December 29, 1994
Creator: Kiesler, J. P.
Object Type: Report
System: The UNT Digital Library
q Profile evolution and enhanced core confinement of high {beta}{sub p} plasmas in DIII-D (open access)

q Profile evolution and enhanced core confinement of high {beta}{sub p} plasmas in DIII-D

In DIII-D the authors have investigated the long pulse evolution of high poloidal beta ({sub beta}{sub p}), double-null diverted H-mode discharges, which exhibit high bootstrap current fractions attractive for a reactor. At low currents I{sub p}, the current profile evolved over several seconds and the on-axis safety factor (q{sub 0}) increased. When q{sub 0} increased above {approximately}2, the MHD character changed from an m/n = 2/1 to an m/n = 3/1 internal kink mode, where m(n) are poloidal (toroidal) mode numbers, which then disappeared with further increases in q{sub 0}. Coincident with a strong reduction of fluctuations, the authors observed enhanced core confinement, leading to strong density peaking, a further rise in {beta}{sub p}, and a bootstrap current increasing to I{sub boot}/I{sub p} {approx} 0.8, peaked within the core. Ideal MHD calculations showed access to second stability during the density rise. During the enhanced performance phase core particle lifetime ({tau}{sub p}) and global energy lifetime ({tau}{sub E}) increased by factors of 2 and 1.2 respectively. Transport analysis showed that core particle and thermal diffusivities D{sub e} and {chi}{sub eff} approached neoclassical values. During the low current experiments, large losses of fast ions (typically {approximately}50% at 0.4 MA) were observed; at …
Date: October 1, 1994
Creator: Stallard, B. W.; Casper, T. A. & Fenstermacher, M. E.
Object Type: Article
System: The UNT Digital Library
Interim essential and support drawing list for K Basins (open access)

Interim essential and support drawing list for K Basins

This document presents a list of essential and support drawings that have been identified as required to achieve the mission objectives of K Basin and are an integral part of the in-progress K Basins system baselining effort. The drawings listed in the appendix are those drawings required to safely operate K Basins. These drawings will be authenticated through the field verification and design reconstitution programs to ensure that these identified drawings are consistent with design requirements.
Date: December 16, 1994
Creator: Langevin, M. J.
Object Type: Report
System: The UNT Digital Library
Integrated Data Base report--1993: U.S. spent nuclear fuel and radioactive waste inventories, projections, and characteristics. Revision 10 (open access)

Integrated Data Base report--1993: U.S. spent nuclear fuel and radioactive waste inventories, projections, and characteristics. Revision 10

The Integrated Data Base Program has compiled historic data on inventories and characteristics of both commercial and DOE spent nuclear fuel; also, commercial and US government-owned radioactive wastes through December 31, 1993. These data are based on the most reliable information available from government sources, the open literature, technical reports, and direct contacts. The information forecasted is consistent with the latest US Department of Energy/Energy Information Administration projections of US commercial nuclear power growth and the expected DOE-related and private industrial and institutional activities. The radioactive materials considered, on a chapter-by-chapter basis, are spent nuclear fuel, high-level waste, transuranic waste, low-level waste, commercial uranium mill tailings, DOE Environmental Restoration Program wastes, commercial reactor and fuel-cycle facility decommissioning wastes, and mixed (hazardous and radioactive) low-level waste. For most of these categories, current and projected inventories are given the calendar-year 2030, and the radioactivity and thermal power are calculated based on reported or estimated isotopic compositions. In addition, characteristics and current inventories are reported for miscellaneous radioactive materials that may require geologic disposal. 256 refs., 38 figs., 141 tabs.
Date: December 1, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Near-extinction and final burnout in coal combustion (open access)

Near-extinction and final burnout in coal combustion

The late stages of char combustion have a special technological significance, as carbon conversions of 99% or greater are typically required for the economic operation of pulverized coal fired boilers. In the present article, two independent optical techniques are used to investigate near-extinction and final burnout phenomenas. Captive particle image sequences, combined with in situ optical measurements on entrained particles, provide dramatic illustration of the asymptotic nature of the char burnout process. Single particle combustion to complete burnout is seen to comprise two distinct stages: (1) a rapid high-temperature combustion stage, consuming about 70% of the char carbon and ending with near-extinction of the heterogeneous reactions due to a loss of global particle reactivity, and (2) a final burnout stage occurring slowly at lower temperatures. For particles containing mineral matter, the second stage can be further subdivided into: (2a) late char combustion, which begins after the near-extinction event, and converts carbon-rich particles to mixed particle types at a lower temperature and a slower rate; and (2b) decarburization of ash -- the removal of residual carbon inclusions from inorganic (ash) frameworks in the very late stages of combustion. This latter process can be extremely slow, requiring over an order of magnitude …
Date: February 1, 1994
Creator: Hurt, R. H. & Davis, K. A.
Object Type: Article
System: The UNT Digital Library
K Basins fuel encapsulation and storage hazard categorization (open access)

K Basins fuel encapsulation and storage hazard categorization

This document establishes the initial hazard categorization for K-Basin fuel encapsulation and storage in the 100 K Area of the Hanford site. The Hazard Categorization for K-Basins addresses the potential for release of radioactive and non-radioactive hazardous material located in the K-Basins and their supporting facilities. The Hazard Categorization covers the hazards associated with normal K-Basin fuel storage and handling operations, fuel encapsulation, sludge encapsulation, and canister clean-up and disposal. The criteria categorizes a facility based on total curies per radionuclide located in the facility. Tables 5-3 and 5-4 display the results in section 5.0. In accordance with DOE-STD-1027 and the analysis provided in section 5.0, the K East Basin fuel encapsulation and storage activity and the K West Basin storage are classified as a {open_quotes}Category 2{close_quotes} Facility.
Date: December 1, 1994
Creator: Porten, D. R.
Object Type: Report
System: The UNT Digital Library
Laboratory Studies of the Sensitivity of Tropospheric Ozone to the Chemistry of Sea Salt Aerosol. Final Report, September 15, 1993--September 14, 1994 (open access)

Laboratory Studies of the Sensitivity of Tropospheric Ozone to the Chemistry of Sea Salt Aerosol. Final Report, September 15, 1993--September 14, 1994

Ozone plays a critical role in both the chemistry and radiation balance of the troposphere. Understanding the factors controlling tropospheric ozone levels is critical to our understanding of a variety of issues in global chemistry and climate change. Chlorine atoms have the potential to contribute significantly to the ozone balance in the free troposphere. They can react directly with ozone or alternately, with organics and may actually lead to the formation of ozone in the presence of sufficient NO. Reactions of alkali halides in sea salt particles are a potential source of atomic chlorine, hence reactions of these alkali halides, especially those producing precursors to atomic chlorine, are of great interest. Finally, the mechanisms, intermediates and products of the Cl-biogenic reactions are unknown; these could serve as unique markers of chlorine atom chemistry in the troposphere, and hence are important to define.
Date: November 15, 1994
Creator: Finlayson-Pitts, B. J.
Object Type: Report
System: The UNT Digital Library
Environmental, health, and safety issues of fuel cells in transportation. Volume 1: Phosphoric acid fuel-cell buses (open access)

Environmental, health, and safety issues of fuel cells in transportation. Volume 1: Phosphoric acid fuel-cell buses

The U.S. Department of Energy (DOE) chartered the Phosphoric Acid Fuel-Cell (PAFC) Bus Program to demonstrate the feasibility of fuel cells in heavy-duty transportation systems. As part of this program, PAFC- powered buses are being built to meet transit industry design and performance standards. Test-bed bus-1 (TBB-1) was designed in 1993 and integrated in March 1994. TBB-2 and TBB-3 are under construction and should be integrated in early 1995. In 1987 Phase I of the program began with the development and testing of two conceptual system designs- liquid- and air-cooled systems. The liquid-cooled PAFC system was chosen to continue, through a competitive award, into Phase H, beginning in 1991. Three hybrid buses, which combine fuel-cell and battery technologies, were designed during Phase III. After completing Phase II, DOE plans a comprehensive performance testing program (Phase HI) to verify that the buses meet stringent transit industry requirements. The Phase III study will evaluate the PAFC bus and compare it to a conventional diesel bus. This NREL study assesses the environmental, health, and safety (EH&S) issues that may affect the commercialization of the PAFC bus. Because safety is a critical factor for consumer acceptance of new transportation-based technologies the study focuses on …
Date: December 1, 1994
Creator: Ring, S.
Object Type: Report
System: The UNT Digital Library
B-Physics results from D0 (open access)

B-Physics results from D0

We report on preliminary measurements of the inclusive single muon and dimuon cross sections in p{bar p} collisions at {radical}s = 1.8 TeV using the D0 detector at the Fermilab collider. From these results, we extract the cross section for b-quark production for the kinematic range {vert_bar}yb{vert_bar} < 1.0 and 6 < p{sub t}{sup b} < 50 GeV/c. We also report measurements on the J/{psi} production, and correlations between muons in dimuon events.
Date: December 1, 1994
Creator: Hedin, D. & Markosky, L.
Object Type: Article
System: The UNT Digital Library
A tool for designing pollution prevention into US Department of Energy facilities (open access)

A tool for designing pollution prevention into US Department of Energy facilities

Historically, pollution prevention activities within the Department of Energy (DOE) have focused on existing process waste streams. However, the DOE estimates that 70 percent of the opportunity to reduce or eliminate pollutants is gained or lost during design. Design is considered a critical component of the DOE`s operations, products and services, as evidenced by the numerous new facilities planned to support the cleanup mission of the complex. Pollution prevention during design: (a) significantly reduces the potential generation of waste and environmental releases, (b) promotes the use of energy efficient materials, (c) minimizes resource consumption, and (d) lowers life-cycle costs. Life-cycle cost considerations during design can include construction, operation, and eventual decommissioning of the facility. This paper highlights: (1) the development of the guideline, including specific examples of the guideline`s content and intended use, (2) a discussion on the philosophy and content of the training module, (3) a strategy for integrating the guideline`s use into the existing DOE design process, and (4) future plans for enhancing the guideline and training class while continuing to integrate pollution prevention into the DOE design process.
Date: January 1, 1994
Creator: Dorsey, J. A.; Raney, E. A. & Whitehead, J. K.
Object Type: Article
System: The UNT Digital Library
Petroleum marketing monthly, January 1994 (open access)

Petroleum marketing monthly, January 1994

The Petroleum Marketing Monthly (PMM) is designed to give information and statistical data about a variety of crude oils and refined petroleum products. The publication provides statistics on crude oil costs and refined petroleum products sales for use by industry, government, private sector analysts, educational institutions, and consumers. Data on crude oil include the domestic first purchase price, the f.o.b. and landed cost of imported crude oil, and the refiners` acquisition cost of crude oil. Sales data for motor gasoline, distillates, residuals, aviation fuels, kerosene, and propane are presented.
Date: February 1, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library