New signatures for phase/shape transitional regions (open access)

New signatures for phase/shape transitional regions

The energies of low-spin yrast states, E(4{sub 1}{sup +}) and E(2{sub 1}{sup +}), and the transition probabilities, B(E2; 2{sub 1}{sup +} {yields} 0{sub 1}{sup +}), which are among the most revealing and easiest to measure observables of collectivity, show remarkable global correlations that provide new signatures to identify particular structures.
Date: July 1, 1993
Creator: Zamfir, N. V.; Casten, R. F.; Zhang, J. Y. & Brenner, D. S.
Object Type: Article
System: The UNT Digital Library
Characterization of porosity via secondary reactions. Quarterly technical progress report, 1 January 1993--31 March 1993 (open access)

Characterization of porosity via secondary reactions. Quarterly technical progress report, 1 January 1993--31 March 1993

Temperature-programmed desorption spectra from steam-gasified chars were examined. At least two major CO-liberating features were identified for the resin char samples, one centered 1000 C and the other 1050 C. Presence of catalytic mineral matter appears to be related to the appearance of an additional low temperature feature for the Wyodak char. Although total amount of surface oxygen seems to be a gross indicator of reactivity, analysis of the desorption data assuming two different types of oxygen surface complexes, each exhibiting a single desorption activation energy, shows that the reactivity cannot be explained by the desorption rates of the complexes alone. 6 figs, 4 tabs, 9 refs.
Date: July 1, 1993
Creator: Calo, J. M.; Lu, W. & Zhang, L.
Object Type: Report
System: The UNT Digital Library
Task J: Outstanding Junior Investigator (OJI). Technical progress report, [November 1, 1993--October 31, 1993] (open access)

Task J: Outstanding Junior Investigator (OJI). Technical progress report, [November 1, 1993--October 31, 1993]

We report on an existing program of research on the production and decay of particles containing the charm and beauty quarks. Charm is studied in Fermilab fixed target experiments E769 and E691. Design and development for a hadron collider beauty experiment is studied in CERN test experiment P238 and in simulation studies for the SSC.
Date: July 6, 1993
Creator: Karchin, P. E.
Object Type: Report
System: The UNT Digital Library
Fabrication of the APS Storage Ring radio frequency accelerating cavities (open access)

Fabrication of the APS Storage Ring radio frequency accelerating cavities

Specification, heat treatment, strength, and fatigue life of the Advanced Photon Source (APS) Storage Ring 352-MHz radio frequency (RF) accelerating cavity copper is discussed. Heat transfer studies, including finite element analysis, and configuration of water cooling is described. Requirements for and techniques of machining are considered. Braze and electron beam joint designs are compared. Vacuum considerations during fabrication are discussed.
Date: July 1, 1993
Creator: Primdahl, K.; Bridges, J.; DePaola, F.; Kustom, R. & Snee, D.
Object Type: Article
System: The UNT Digital Library
Fischer Tropsch synthesis in supercritical fluids. Quarterly technical progress report, January 1, 1993--March 31, 1993 (open access)

Fischer Tropsch synthesis in supercritical fluids. Quarterly technical progress report, January 1, 1993--March 31, 1993

Our objective during the second quarter of the project was to complete the procurement of necessary parts for our reactor set-up, complete equipment modification, start safety and shake-down tests and complete preliminary calculations that are needed before starting experimentation. The experimental set-up was completed. Different pieces of equipment such as the reactor, the mass flow controller, steady state low pressure glass trap, etc. were installed in the system. The system was then pressure tested for safety purposes. There were many aspects of the safety tests like the cold pressure tests, the hot pressure tests, the flow through tests, etc. All these tests were successfully completed. various safety devices in the set-up such as relief valves, temperature interlocks, solenoid valves and the emergency shut-down system were also tested successfully.
Date: July 1, 1993
Creator: Akgerman, A. & Bukur, D. B.
Object Type: Report
System: The UNT Digital Library
Tank Farm surveillance and waste status summary report for April 1993 (open access)

Tank Farm surveillance and waste status summary report for April 1993

This report is the official inventory for radioactive waste stored in underground tanks in the 200 Areas at the Hanford Site. Data that depict the status of stored radioactive waste and tank vessel integrity are contained within the report. This report provides data on each of the existing 177 large underground waste storage tanks and 49 smaller catch tanks and special surveillance facilities, and supplemental information regarding tank surveillance anomalies and ongoing investigations.
Date: July 1, 1993
Creator: Hanlon, B. M.
Object Type: Report
System: The UNT Digital Library
Fundamental studies of passivity and passivity breakdown (open access)

Fundamental studies of passivity and passivity breakdown

We developed and experimentally tested physical models for growth and breakdown of passive films on metal surfaces. These models are ``point defect models,`` in which the growth and breakdown are described in terms of movement of anion and cation vacancies. The work during the past 5 years resulted in: theory of growth and breakdown of passive films, theory of corrosion-resistant alloys, electronic structure of passive films, and estimation of damage functions for energy systems. Proposals are give for the five ongoing tasks. 10 figs.
Date: July 1, 1993
Creator: Macdonald, D. D.
Object Type: Report
System: The UNT Digital Library
Performance viewing and editing in ASSESS Outsider (open access)

Performance viewing and editing in ASSESS Outsider

The Analytic System and Software for Evaluation of Safeguards and Security (ASSESS) Facility module records site information in the path elements and areas of an Adversary Sequence Diagram. The ASSESS Outsider evaluation module takes this information and first calculates performance values describing how much detection and delay is assigned at each path element and then uses the performance values to determine most-vulnerable paths. This paper discusses new Outsider capabilities that allow the user to view how elements are being defeated and to modify some of these values in Outsider. Outsider now displays how different path element segments are defeated and contrasts the probability of detection for alternate methods of defeating a door (e.g., the lock or the door face itself). The user can also override element segment delays and detection probabilities directly during analysis in Outsider. These capabilities allow users to compare element performance and to verify correct path element performance for all elements, not just those on the most-vulnerable path as is the case currently. Improvements or reductions in protection can be easily checked without creating a set of new facility files to accomplish it.
Date: July 1, 1993
Creator: Snell, M. K.; Key, B. & Bingham, B.
Object Type: Article
System: The UNT Digital Library
Recent results in explosive and s-process nucleosynthesis from measurements on radioactive and stable targets (open access)

Recent results in explosive and s-process nucleosynthesis from measurements on radioactive and stable targets

Measurements of (n,p) and (n,{alpha}) cross sections are crucial for a better understanding of many scenarios of nucleosynthesis. Current problems in which such reactions play a roll include the possible synthesis of heavy element during the big bang. The production of several rare isotopes in explosive nucleosynthesis, and a better understanding of the role of the s process in the synthesis of light and intermediate mass nuclei. We have recently completed measurements of several (n,p) and (n,{alpha}) cross sections of importance to nuclear astrophysics. The cross sections were measured in the range from thermal energy to approximately 1 MeV by using the white neutron source at the Manuel Lujan, Jr. Neutron Scattering Center (LANSCE) in Los Alamos. We have also made complementary measurements at the Karlsruhe Van de Graaff and at thee Oak Ridge Electron Linear Accelerator (ORELA). We discuss the impact of the results on nuclear astrophysics as well as recent improvements and future plans.
Date: July 1, 1993
Creator: Koehler, P. E.; Kaeppeler, F. & Schatz, H.
Object Type: Article
System: The UNT Digital Library
Photochemical dynamics of surface oriented molecules. Progress report, August 1, 1992--July 31, 1993 (open access)

Photochemical dynamics of surface oriented molecules. Progress report, August 1, 1992--July 31, 1993

Photodesorption and photoreaction was investigated using a mass spectrometer, on O{sub 2} alone and coadsorbed with CO on Pt(111) at 80 K. Desorption of O{sub 2} continues for 1 ps, indicating multiple excitation of adsorbed O{sub 2} by photogenerated hot electrons. The branching ratio for O{sub 2} desorption to CO{sub 2} product formation increases as the O{sub 2} is photoexcited by femtosecond light pulses, in contrast to the larger CO{sub 2} photoyield for nanosecond laser excitation.
Date: July 1, 1993
Creator: Ho, W.
Object Type: Report
System: The UNT Digital Library
Authenticated In-Plant Process Monitor (open access)

Authenticated In-Plant Process Monitor

Transparent and secure process monitoring systems may become an important tool in the dismantlement schemes in support of bilateral and multi-lateral treaties. A prototype system, using public key cryptography to authenticate compliance data, has been developed by Sandia National Laboratories. The Authenticated In-plant Process Monitor (AIPM) is an embedded process monitoring system capable of accepting up to sixteen industry standard process variables, at sample rates of up to two samples per second. Each AIPM will synchronously sample the process, authenticate, and transmit the data in real-time to the host receiving station. The receiving station will validate the compliance data and then display in real-time while updating a relational database. This new generation of monitoring systems must include protection from a host of possible threat scenarios while providing the user authentic clear text data. Data threats are controlled by the use of a public key Treaty Data Authentication Module (TDAM) utilizing the National Institute of Standards and Technology (NIST) Digital Signature Standard. System threats are minimized by the use of a tamper indicating enclosure that monitors unauthorized entry and environmental attacks. Insider threats will be controlled by the use of an authenticated bi-directional communication link between each remote AIPM and the …
Date: July 1, 1993
Creator: Leahy, P. & Draelos, T.
Object Type: Article
System: The UNT Digital Library
An investigation of Inventory Differences (open access)

An investigation of Inventory Differences

The derivation of applicable Limits of Error for Inventory Differences (LEIDs) has been a long-term challenge for some material storage tanks at the Savannah River Site. Several investigations have been unsuccessful in producing usable estimates of the LEIDs. An investigation conducted in November of 1991 revealed some significant inventory characteristics. The corrective action involved the implementation of a multi-case LEID based on historical information and a correction in the use of the tank calibration charts for two storage tanks.
Date: July 1, 1993
Creator: Harvel, C.
Object Type: Article
System: The UNT Digital Library
Evaluation of diurnal thermal energy storage combined with cogeneration systems. Phase 2 (open access)

Evaluation of diurnal thermal energy storage combined with cogeneration systems. Phase 2

This report describes the results of a study of thermal energy storage (TES) systems integrated with combined-cycle gas turbine cogeneration systems. Integrating thermal energy storage with conventional cogeneration equipment increases the initial cost of the combined system; but, by decoupling electric power and process heat production, the system offers two significant advantages. First, electric power can be generated on demand, irrespective of the process heat load profile, thus increasing the value of the power produced. Second, although supplementary firing could be used to serve independently varying electric and process heat loads, this approach is inefficient. Integrating TES with cogeneration can serve the two independent loads while firing all fuel in the gas turbine. An earlier study analyzed TES integrated with a simple-cycle cogeneration system. This follow-on study evaluated the cost of power produced by a combined-cycle electric power plant (CC), a combined-cycle cogeneration plant (CC/Cogen), and a combined-cycle cogeneration plant integrated with thermal energy storage (CC/TES/Cogen). Each of these three systems was designed to serve a fixed (24 hr/day) process steam load. The value of producing electricity was set at the levelized cost for a CC plant, while the value of the process steam was for a conventional stand-alone boiler. …
Date: July 1, 1993
Creator: Somasundaram, S.; Brown, D. R. & Drost, M. K.
Object Type: Report
System: The UNT Digital Library
The partial snake experiment at the AGS. Progress report, 15 August 1992--14 August 1994 (open access)

The partial snake experiment at the AGS. Progress report, 15 August 1992--14 August 1994

In the two year funding period from August 15, 1992--August 14, 1994, the authors progresses can be summarized as follows: (1) the solenoidal partial snake was installed in the AGS synchrotron in May, 1993 and was subsequently successfully tested; (2) the internal polarimeter for the AGS was assembled, tested and installed in the AGS; (3) the 200 MeV polarimeter at the LINAC was tested; (4) the AGS polarized ion source was renovated; (5) the first phase of the polarized beam experiments was successfully accomplished in April 1--8, 1994, of polarized proton acceleration up to G{sub {gamma}} {approx} 20; (6) they are currently renovating tune jump quadrupoles in order to accelerate polarized proton up to 25 GeV/c. The full test of these experiments will be in 1995. During this funding period, the principal investigator has spent about 20% of his research time on this project, which includes the design and manufacturing of the solenoid partial snake, beam dynamics issues of the AGS with the 5% solenoid partial snake and spin dynamics of synchrotrons with snakes in general. The graduate student, Mr. H. Huang has spent 100% of his research time working on spin dynamics. The graduate student is currently staying at …
Date: July 15, 1993
Creator: Lee, S. Y.
Object Type: Report
System: The UNT Digital Library
Inflow characteristics associated with high-blade-loading events in a wind farm (open access)

Inflow characteristics associated with high-blade-loading events in a wind farm

The stochastic characteristics of the turbulent inflow have been shown to be of major significance in the accumulation of fatigue in wind turbines. Because most of the wind turbine installations in the US have taken place in multi-turbine or wind farm configurations, the fatigue damage associated with the higher turbulence levels within such arrangements must be taken into account when making estimates of component service lifetimes. The simultaneous monitoring of two adjacent wind turbines over a wide range of turbulent inflow conditions has given the authors more confidence in describing the structural load distributions that can be expected in such an environment. The adjacent testing of the two turbines allowed the authors to postulate that observed similarities in the response dynamics and load distributions could be considered quasi-universal, while the dissimilarities could be considered to result from the differing design of the rotors. The format has also allowed them to begin to define appropriate statistical load distribution models for many of the critical components in which fatigue is a major driver of the design. In addition to the adjacent turbine measurements, they also briefly discuss load distributions measured on a teetered-hub turbine.
Date: July 1, 1993
Creator: Kelley, N. D.
Object Type: Report
System: The UNT Digital Library
Fuel cell systems program plan, Fiscal year 1993 (open access)

Fuel cell systems program plan, Fiscal year 1993

DOE Office of Fossil Energy (OoFE) is participating with private sector in developing molten carbon fuel cell (MCFC) and advanced concepts including solid oxide fuel cell for application in utility/commercial/industrial sectors. Phosphoric acid fuel cell (PAFC) development was sponsored by OoFE and is now being commercialized. In 1993 DOD is undertaking use and demonstration of PAFC and other fuel cells. DOE Office of Conservation and Renewable Energy is sponsoring fuel cell development for propulsion. The Conservation program is focused on polymer electrolyte or proton exchange membrane fuel cells, although they also are implementing a demonstration program for PAFC buses. DOE fuel cell research, development and demonstration efforts are also supported by private sector funding. This Plan describes the fuel cell activities of the Office of Fossil Energy.
Date: July 1, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
A risk comparison for startup of plutonium thermal stabilization operations (open access)

A risk comparison for startup of plutonium thermal stabilization operations

Plutonium production operations at the Rocky Flats Plant were curtailed in 1989 by the Department of Energy so that a new operating contractor, EG&G Rocky Flats Inc., could assess the safety of resuming plutonium operations and implement a new safety culture consistent with nuclear reactor practices. In 1992, the Plant`s mission was changed to decommissioning, decontamination, and environmental restoration. In order to support this new mission, a safety analysis for Building 707 required rebaselining of the risk of resuming thermal stabilization of pyrophoric forms of plutonium by electrical heating in an air environment, as well as other activities to support the building in a standby and interim storage mode. The general approach was to update the safety analysis that rebaselined risks from fires, explosions, spills, criticalities, and seismic events for the previous production mission. Event tree analyses of the risk dominant scenarios were modified to establish accident sequence frequencies for the new mission. Radiological source terms were revised to reflect the quantities of plutonium at risk for the new mission. While the total amount of plutonium metal is reduced due to the mission change, the amount of plutonium oxide powder is expected to be greater. Radiological consequences and risks were …
Date: July 1, 1993
Creator: Elia, F. Jr.; Foppe, T. L. & Stahlnecker, E.
Object Type: Article
System: The UNT Digital Library
The shock Hugoniot of 316 ss and sound velocity measurements (open access)

The shock Hugoniot of 316 ss and sound velocity measurements

Type 316 stainless steel has been characterized for its high-pressure, shock-wave response. Measurements have been made of shock-wave and particle velocity, and of sound velocity. Our preliminary results for shock and particle velocity have been combined with previously unpublished results, and an overall fit made. Sound velocity results show a discontinuity that is attributed to shock-induced melting.
Date: July 1, 1993
Creator: Hixson, R. S.; McQueen, R. G. & Fritz, J. N.
Object Type: Article
System: The UNT Digital Library
The changing structure of the US coal industry: An update, July 1993 (open access)

The changing structure of the US coal industry: An update, July 1993

Section 205(a)(2) of the Department of Energy Organization Act of 1977 requires the Administrator of the Energy Information Administration (EIA) to carry out a central, comprehensive, and unified energy data and information program that will collect, evaluate, assemble, analyze, and disseminate data and information relevant to energy resources, reserves, production, demand, technology, and related economic and statistical information. The purpose of this report is to provide a comprehensive overview of changes in the structure of the US coal industry between 1976 and 1991. The structural elements examined include the number of mines, average mine size, the size distribution of mines, and the size distribution of coal firms. The report measures changes in the market shares of the largest coal producers at the national level and in various regions. The Central Appalachian low-sulfur coal market is given special attention, and the market for coal reserves is examined. A history of mergers in the coal industry is presented, and changes in the proportions of US coal output that are produced by various types of companies, including foreign-controlled firms, are described. Finally, the impact of post-1991 mergers on the structure of the industry is estimated. The legislation that created the EIA vested the …
Date: July 29, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Variations in convective venting to increase the efficiency of compact fluorescent downlights (open access)

Variations in convective venting to increase the efficiency of compact fluorescent downlights

In most compact fluorescent recessed downlights, hot air stratifies within the fixture, causing the lamps to overheat and lose up to 25% of light output and efficacy. Thermal management techniques, including passive venting of the fixture, are being developed to mitigate these losses in fixture efficiency. This paper demonstrates a sequence of venting configurations and techniques, from an unmodified compact fluorescent downlight as a control fixture, through a series of venting strategies, to the development of a highly efficient downlight that incorporates a new angular concept in convective venting. With this new venting design, an increase in light output of nearly 25% can be attained without the optical losses generally associated with some venting geometries.
Date: July 1, 1993
Creator: Siminovitch, M.; Zhang, C. & Kleinsmith, N.
Object Type: Article
System: The UNT Digital Library
Instrumentation of Dynamic Gas Pulse Loading system. Final technical report (open access)

Instrumentation of Dynamic Gas Pulse Loading system. Final technical report

The Dynamic Gas Pulse Loading (DGPL) process is an hydraulic fracturing method which uses CO{sub 2} and CO gas as a working fluid instead of a liquid. The DGPL system can be used to generate fractures for horizontal and vertical oil and gas well completions in both open hole and perforated casing. The DGPL system provides a cost effective tool for repairing near well bore permeability damage caused by inappropriate chemical treatment, migrating fines and paraffins, or slotted liners blocked by sand. Because the gas is generated from a solid propellant material by chemical reaction, no heavy equipment is required. Tremendous pump rates can be obtained. Peak pressures are naturally localized at the tool position by the tamping effect of well fluids. Thus many of the leakage and sealing problems which plague static hydrofrac processes ore completely avoided. DGPL may be effectively used before acid treatment to provide fresh pathways for the acid to reach the formation. The smaller tools may be positioned by wireline, though most Stressfrac tools are tubing conveyed.
Date: July 31, 1993
Creator: Mohaupt, H.
Object Type: Report
System: The UNT Digital Library
High heat flux engineering in solar energy applications (open access)

High heat flux engineering in solar energy applications

Solar thermal energy systems can produce heat fluxes in excess of 10,000 kW/m{sup 2}. This paper provides an introduction to the solar concentrators that produce high heat flux, the receivers that convert the flux into usable thermal energy, and the instrumentation systems used to measure flux in the solar environment. References are incorporated to direct the reader to detailed technical information.
Date: July 1, 1993
Creator: Cameron, C. P.
Object Type: Article
System: The UNT Digital Library
The theory of relativistic heavy ion collisions. Progress report (open access)

The theory of relativistic heavy ion collisions. Progress report

This program began in January 1993. Its primary goals are studies of highly excited matter and its production in nuclear collisions at very high energies. After a general orientation on the project, abstracts describing the contents of completed papers and providing some details of current projects are given. Principal topics of interest are the following: the dynamics of nuclear collisions at very high energies (RHIC and LHC), the dynamics of nuclear collisions at AGS energies, high-temperature QCD and the physics of the quark-gluon plasma, and the production of strangelets and other rare objects.
Date: July 1, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
X-ray plasma source design simulations (open access)

X-ray plasma source design simulations

The optimization of soft x-ray production from a laser-produced plasma for lithographic applications is discussed in the context of recent experiments by R. Kauffman et al. which indicate that a conversion efficiency of 0.01 can be obtained with Sn targets at modest laser intensity. Computer simulations of the experiments delineate the critical phenomena underlying these high conversion efficiencies, especially the role of hydrodynamic expansion and radiative emission. Qualitative features of the experiments are reproduced including the transition from one-dimensional to two-dimensional flow. The quantitative discrepancy is ascribed to incorrect initiation of the ablating plasma and to inadequate atomic transition rate evaluation.
Date: July 1, 1993
Creator: Cerjan, C.
Object Type: Article
System: The UNT Digital Library