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Bounding burnout risk power limits for the K-14 cycle (open access)

Bounding burnout risk power limits for the K-14 cycle

This document discusses burnout risk (BOR) power limits which are designed to protect the reactor from a significant release of fission products, due to critical heat flux (CHF) burnout of fuel and target assemblies. At expected operating power levels for the reactor restart, approximately 50% of historical full power, the risk of CHF and attendant burnout is negligible. Flow instability power limits will restrict reactor operation, and flow instability will always occur before CHF. BOR power limits must nevertheless be calculated because they are required by the reactor control computer, (2) Bounding BOR limits have been calculated for the K-14 cycle, to fulfill this requirement, and they are presented in this document. Two sets of BOR limits have been calculated: one applicable for the first subcycle, zero to 30% fuel burnup, and the other for the second subcycle, 30% to 55% fuel burnup.
Date: October 1, 1990
Creator: Shadday, M.A. Jr.
Object Type: Report
System: The UNT Digital Library
Hydrological and geochemical investigations of selenium behavior at Kesterson Reservoir (open access)

Hydrological and geochemical investigations of selenium behavior at Kesterson Reservoir

From 1985 to the present we have studied the behavior of selenium in various habitats and environments at Kesterson reservoir, shifting emphasis as remedial actions altered the physical setting. Investigations have evaluated the efficacy of several remedial alternatives, from innovative techniques relying on the complex geochemical behavior of selenium alternatives, from innovative techniques relying on the complex geochemical behavior of selenium in aquatic environments to conventional excavation schemes. Results of these studies supported two cost-effective remedial measures; drain water deliveries were terminated in 1986 and, in 1988, 1 million cubic yards of soil were imported and used to fill the low lying areas of the former Kesterson Reservoir. To date, these two actions appear to have eliminated the aquatic habitat that caused waterfowl death and deformity at Kesterson from the early 1980's to 1987. Biological, surface water and groundwater monitoring data collected by the USBR indicate that Kesterson is now a much safer environment than in past years when drainage water containing 300{mu}g/l of selenium was delivered to the Reservoir. The continued presence of a large inventory of selenium within the upper portions of unfilled areas of Kesterson Reservoir and immediately below the fill material requires that a continued awareness …
Date: October 1, 1990
Creator: Benson, S. M.; Tokunaga, T. K.; Zawislanski, P.; Yee, A. W.; Daggett, J. S.; Oldfather, J. M. et al.
Object Type: Report
System: The UNT Digital Library
Pattern recognition in gamma-gamma coincidence data sets (open access)

Pattern recognition in gamma-gamma coincidence data sets

Considerable amounts of tedious labor are required to manually scan high-resolution 1D slices of two dimensional {gamma}-{gamma} coincident matrices for relevant and exciting structures. This is particularly true when the interesting structures are of weak intensity. We are working on automated search methods for the detection of rotational band structures in the full 2D space using pattern recognition techniques. For nominal sized data sets (1024{times}1024), however, these techniques only become computationally feasible through the use of Fourier Transform methods. Furthermore the presentation of data matrices as images rather than series of 1D spectra has been shown to be useful. In this paper we will present the data manipulation techniques we have developed.
Date: October 1, 1990
Creator: Manatt, D. R.; Barnes, F. L.; Becker, J. A.; Candy, J. V.; Henry, E. A. (Lawrence Livermore National Lab., CA (United States)) & Brinkman, M. J. (Rutgers--the State Univ., New Brunswick, NJ (United States))
Object Type: Article
System: The UNT Digital Library
Design options for low-conductivity window frames (open access)

Design options for low-conductivity window frames

The window industry's commercialization of low-emissivity coatings and low-conductivity gas-filling over the past few years has helped to drastically reduce heat transfer rates through the glazed areas of windows. However, few changes have taken place in the design and construction of window frames and edges, leaving these elements to account for most of the heat transfer through today's state-of-the-art windows. This paper presents design and material requirements for the manufacture of low-conductivity window frames obtained through the use of finite element computer modeling. Such frames will compliment and not degrade today's most energy-efficient insulated glass units. 7 refs., 2 figs., 5 tabs.
Date: October 1, 1990
Creator: Byars, N. & Arasteh, D.
Object Type: Report
System: The UNT Digital Library

Guest Artist Recital: 1990-10-01 - C. James Sheppard-EVI and EWI midi controllers, composer

Access: Use of this item is restricted to the UNT Community
Guest artist recital performed at the UNT College of Music Merrill Ellis Intermedia Theater.
Date: October 1, 1990
Creator: Sheppard, C. James (Charles James), 1943-
Object Type: Sound
System: The UNT Digital Library
Si(Li) detectors with thin dead layers for low energy x-ray detection (open access)

Si(Li) detectors with thin dead layers for low energy x-ray detection

Regions of incomplete charge collection, or dead layers'', are compared for Si(Li) detectors fabricated with Au and Pd entrance window electrodes. The dead layers were measured by characterizing the detector spectral response to x-ray energies above and below the Si K{alpha} absorption edge. It was found that Si(Li) detectors with Pd electrodes exhibit consistently thinner effective Si dead layers than those with Au electrodes. Furthermore, it is demonstrated that the minimum thickness required for low resistivity Pd electrodes is thinner than that required for low resistivity Au electrodes, which further reduces the signal attenuation in Pd/Si(Li) detectors. A model, based on Pd compensation of oxygen vacancies in the SiO{sub 2} at the entrance window Si(Li) surface, is proposed to explain the observed differences in detector dead layer thickness. Electrode structures for optimum Si(Li) detector performance at low x-ray energies are discussed. 18 refs., 8 figs., 1 tab.
Date: October 1, 1990
Creator: Rossington, C.S.; Walton, J.T. & Jaklevic, J.M.
Object Type: Article
System: The UNT Digital Library
Energy dissipation in chemical reactions on ultrafast timescales (open access)

Energy dissipation in chemical reactions on ultrafast timescales

A series of picosecond experiments and computer simulations will be presented that test collisional and hydrodynamic models for vibrational relaxation in liquids. The relationships between isolated binary collision models (IBC) and stochastic dynamics will be presented. The appropriateness of IBC theory in describing vibrational relaxation in liquids will also be discussed.
Date: October 1, 1990
Creator: Russell, D. J.; Paige, M. E. & Harris, C. B.
Object Type: Article
System: The UNT Digital Library
Some new approaches to semiclassical and quantum transition state theory (open access)

Some new approaches to semiclassical and quantum transition state theory

Semiclassical and quantum mechanical transition state theory is reviewed and two new approaches described. One is general implementation of a semiclassical rate expression that involves the good'' action-angle variables associated with the saddle point (i.e., transition state) of a potential energy surface. The other is an evaluation of a formally exact quantum expression for the rate in terms of Siegert eigenvalues associated with the transition state. Siegert eigenvalues are usually associated with scattering resonances, so their identification with the saddle point of a potential surface, and the expression for the reaction rate in terms of them, is quite an unexpected and novel development. 14 refs.
Date: October 1, 1990
Creator: Miller, W.H.
Object Type: Article
System: The UNT Digital Library
Low cost hydrogen/novel membrane technology for hydrogen separation from synthesis gas (open access)

Low cost hydrogen/novel membrane technology for hydrogen separation from synthesis gas

The production of hydrogen from synthesis gas made by gasification of coal is expensive. The separation of hydrogen from synthesis gas is a major cost element in the total process. In this report we describe the results of a program aimed at the development of membranes and membrane modules for the separation and purification of hydrogen from synthesis gas. The performance properties of the developed membranes were used in an economic evaluation of membrane gas separation systems in the coal gasification process. Membranes tested were polyetherimide and a polyamide copolymer. The work began with an examination of the chemical separations required to produce hydrogen from synthesis gas, identification of three specific separations where membranes might be applicable. A range of membrane fabrication techniques and module configurations were investigated to optimize the separation properties of the membrane materials. Parametric data obtained were used to develop the economic comparison of processes incorporating membranes with a base-case system without membranes. The computer calculations for the economic analysis were designed and executed. Finally, we briefly investigated alternative methods of performing the three separations in the production of hydrogen from synthesis gas. The three potential opportunities for membranes in the production of hydrogen from synthesis …
Date: October 1, 1990
Creator: Baker, R.W.; Bell, C.M.; Chow, P.; Louie, J.; Mohr, J.M.; Peinemann, K.V. et al.
Object Type: Report
System: The UNT Digital Library
Plan for advanced microelectronics processing technology application (open access)

Plan for advanced microelectronics processing technology application

The ultimate objective of the tasks described in the research agreement was to identify resources primarily, but not exclusively, within New York State that are available for the development of a Center for Advanced Microelectronics Processing (CAMP). Identification of those resources would enable Brookhaven National Laboratory to prepare a program plan for the CAMP. In order to achieve the stated goal, the principal investigators undertook to meet the key personnel in relevant NYS industrial and academic organizations to discuss the potential for economic development that could accompany such a Center and to gauge the extent of participation that could be expected from each interested party. Integrated of these discussions was to be achieved through a workshop convened in the summer of 1990. The culmination of this workshop was to be a report (the final report) outlining a plan for implementing a Center in the state. As events unfolded, it became possible to identify the elements of a major center for x-ray lithography on Lone Island at Brookhaven National Laboratory. The principal investigators were than advised to substitute a working document based upon that concept in place of a report based upon the more general CAMP workshop originally envisioned. Following that …
Date: October 1, 1990
Creator: Goland, A.N.
Object Type: Report
System: The UNT Digital Library
A study of signal generation and charge collection in a-Si:H diodes for radiation imaging (open access)

A study of signal generation and charge collection in a-Si:H diodes for radiation imaging

Its high radiation resistivity and large-area capability are the expected advantages of this material together with its ability to provide a front-end readout electronics in the vicinity of the sensor element. Electrons and holes created by incoming charged particles, X-rays, {gamma} rays, are drifted by the electric field inside a-Si:H diodes and this carrier movement induces signal charges on electrodes. Charge collection and signal generation process are analyzed in terms of carrier mobilities, lifetimes and electric field. Charge collection in thick a-Si:H diodes is often limited by deep-level trapping of carriers during transit and a finite charge integration time required for single particle counting in some applications and sometimes by volume recombination of carriers for detecting heavily-ionizing particles such as {alpha} particles. The charge collection process is also strongly affected by the non-uniform electric field profiles in a-Si:H diodes caused by the fixed space charges inside the material under reverse-bias. Signal generation due to a weak light pulse irradiating each end of a thick diode is measured as a function of a reverse-bias and it gives a valuable information about the fixed space charges. Field profiles can be manipulated by either doping, electrode geometry, or combination of both to improve …
Date: October 1, 1990
Creator: Fujieda, I.
Object Type: Report
System: The UNT Digital Library
Analysis of source-receptor relationships for sulfur compounds using spatial and trend techniques (open access)

Analysis of source-receptor relationships for sulfur compounds using spatial and trend techniques

The National Acid Precipitation Assessment Program (NAPAP) recently published its Integrated Assessment, which describes the causes and effects of acidic deposition and presents a comparative evaluation of the effects of future emissions control scenarios (NAPAP 1990). One component of this Integrated Assessment is an empirical investigation of the relationship between emissions and deposition of sulfur compounds, using available data on sulfur dioxide (SO{sub 2}) emissions and wet sulfate (SO{sub 4}{sup =}) deposition. The rationale for such an investigation is twofold: (1) the analyses provide observational evidence that links emissions and deposition, with cause and effect relationships inferred when atmospheric processes are considered, and (2) the analyses apply these relationships to policy questions on source attribution at specific receptors and the linearity between emissions changes and deposition changes. This paper summarizes the analysis of the empirical relationship between sources and wet deposition of sulfur compounds presented in Question 2 of the Integrated Assessment. A spatial analysis of the relationship between emissions and wet deposition is presented for 1985. The relationship between trends in emissions and wet deposition is presented for the period from 1979 to 1987. The results of these analyses are discussed in the context of the role such information …
Date: October 1, 1990
Creator: Renne, D. S.; Barchet, W. R.; Olsen, A. R. (Pacific Northwest Lab., Richland, WA (USA)); Shannon, J. D. & Sisterson, D. L. (Argonne National Lab., IL (USA))
Object Type: Article
System: The UNT Digital Library
The dynamic market for SO sub 2 emissions permits under the proposed clean air act amendments (open access)

The dynamic market for SO sub 2 emissions permits under the proposed clean air act amendments

This report describes two models CSTM and AUSM, applied to meeting SO{sub 2} emission standards. The CSTM model is a coal market model which models supply and coal prices. The AUSM model is a generating plant level electric utility simulation model. (CBS)
Date: October 1, 1990
Creator: Hanson, D. A.; Lurie, G.; Fox, J. (Argonne National Lab., IL (USA)) & Lyon, T. (Indiana Univ., Bloomington, IN (USA))
Object Type: Article
System: The UNT Digital Library
The cost-constrained traveling salesman problem (open access)

The cost-constrained traveling salesman problem

The Cost-Constrained Traveling Salesman Problem (CCTSP) is a variant of the well-known Traveling Salesman Problem (TSP). In the TSP, the goal is to find a tour of a given set of cities such that the total cost of the tour is minimized. In the CCTSP, each city is given a value, and a fixed cost-constraint is specified. The objective is to find a subtour of the cities that achieves maximum value without exceeding the cost-constraint. Thus, unlike the TSP, the CCTSP requires both selection and sequencing. As a consequence, most results for the TSP cannot be extended to the CCTSP. We show that the CCTSP is NP-hard and that no K-approximation algorithm or fully polynomial approximation scheme exists, unless P = NP. We also show that several special cases are polynomially solvable. Algorithms for the CCTSP, which outperform previous methods, are developed in three areas: upper bounding methods, exact algorithms, and heuristics. We found that a bounding strategy based on the knapsack problem performs better, both in speed and in the quality of the bounds, than methods based on the assignment problem. Likewise, we found that a branch-and-bound approach using the knapsack bound was superior to a method based on …
Date: October 1, 1990
Creator: Sokkappa, P.R.
Object Type: Report
System: The UNT Digital Library
Low temperature cold trapping of uranium hexafluoride containing hydrogen fluoride (open access)

Low temperature cold trapping of uranium hexafluoride containing hydrogen fluoride

The use of a freezer-sublimer system operating at low desublimation pressures to replace 10-in. nuclearly safe cold traps for low assay (<5% U-235) uranium hexafluoride (UF{sub 6}) would significantly simplify operations and is economically attractive provided the nuclear safety of the system can be assured. A major requirement of such assurance is the availability of conditions guaranteeing that the nuclear safety design criterion, which requires that the H/U atomic ratio in the condensate in the freezer-sublimer always be less than 0.33 for assays up to 5%, will never be violated. A general vapor pressure equation giving the vapor pressure of HF-UF{sub 6} solutions as a function of temperature and mole fraction UF{sub 6} has been developed. The precision of the data at the 95% confidence level is {plus minus}0.1 torr at temperatures between {minus}100{degree}F and {minus}121{degree}F. The calculated vapor pressure of pure HF is 4.6 torr at {minus}100{degree}F and 3.1 torr at {minus}108{degree}F. Theoretical considerations suggest that the true value will be slightly lower. In experimental studies of the cold trapping operation at {minus}108{degree}F and at a trap pressure of 2.2 torr, only 7.3% of the HF entering the trap was retained in the trap. At a trap pressure of …
Date: October 1, 1990
Creator: Hobbs, W. E.; Barber, E. J. & Jones, C. G.
Object Type: Report
System: The UNT Digital Library
Main ring transition crossing simulations (open access)

Main ring transition crossing simulations

We used ESME to simulate transition crossing in the Main Ring (MR). For the simulations, we followed the MR 29 cycle used currently for {bar p} production with a flat top of 120 GeV. In Sect. II, some inputs are discussed. In Sect. III, we present simulations with space charge turned off so that the effect of nonlinearity can be studied independently. When space charge is turned on in Sect. IV, we are faced with the problem of statistical errors due to binning, an analysis of which is given in the Appendices. Finally in Sects. V and VI, the results of simulations with space charge are presented and compared with the experimental measurements. 7 refs., 6 figs.
Date: October 1, 1990
Creator: Kourbanis, I. & Ng, King-Yuen.
Object Type: Article
System: The UNT Digital Library
Flaw Assessment Guide for High-Temperature Reactor Components Subject to Creep-Fatigue Loading (open access)

Flaw Assessment Guide for High-Temperature Reactor Components Subject to Creep-Fatigue Loading

A high-temperature flaw assessment procedure is described. This procedure is a result of a collaborative effort between Electric Power Research Institute in the United States, Central Research Institute of Electric Power Industry in Japan, and Nuclear Electric plc in the United Kingdom. The procedure addresses preexisting defects subject to creep-fatigue loading conditions. Laws employed to calculate the crack growth per cycle are defined in terms of fracture mechanics parameters and constants related to the component material. The crack-growth laws can be integrated to calculate the remaining life of a component or to predict the amount of crack extension in a given period. Fatigue and creep crack growth per cycle are calculated separately, and the total crack extension is taken as the simple sum of the two contributions. An interaction between the two propagation modes is accounted for in the material properties in the separate calculations. In producing the procedure, limitations of the approach have been identified. 25 refs., 1 fig.
Date: October 1, 1990
Creator: Ainsworth, R. A.; Ruggles, M. B. & Takahashi, Y.
Object Type: Report
System: The UNT Digital Library
In-situ derivative cyclic voltabsorptometric studies on poly-3-methylthiophene (open access)

In-situ derivative cyclic voltabsorptometric studies on poly-3-methylthiophene

Spectroscopic behavior of poly-3-methylthiophene (P3MT) has been studied employing derivative cyclic volt-absorptometric (DCVA) techniques. In the DCVA technique, the derivative absorption signal (dA/dt) is recorded as a function of the applied potential. The dA/dt signals, the spectroscopic analog of electrochemical currents in cyclic voltammetry, are capable of monitoring the potential dependency for the absorption band effectively discriminating against nonfaradaic signals. The DCVA studies on the P3MT system show that the neutral form of P3MT, absorbing at 490 nm (at less than 0.3 V vs. Ag), changes to the radical cation from, which absorbs at 760 nm. Initially, the formation of the radical cation goes through an isosbestic point, indicating that the conversion of the neutral to radical (polaron) form is chemically reversible. However, upon increasing the electrode potential, the rate of the radical formation at 760 nm starts to decrease, with the formation of another band at about 1250 nm, attributable to a quinoid (bipolaron) form. This trend begins above 0.6 V, shifting to a more positive voltage as the thickness of the film grows. This observation indicates that the electrochemical conversion of the neutral to radical form, followed by the quinoid form, is a slow process controlled by the …
Date: October 1, 1990
Creator: Hoier, S.N.; Ginley, D.S. (Sandia National Labs., Albuquerque, NM (USA)) & Park, Su-Moon (New Mexico Univ., Albuquerque, NM (USA). Dept. of Chemistry)
Object Type: Article
System: The UNT Digital Library
Measurement capabilities of the DOE (Department of Energy) Contractors' Standards Laboratories (open access)

Measurement capabilities of the DOE (Department of Energy) Contractors' Standards Laboratories

This report lists the measurement capabilities of the Department of Energy Contractors' Standard Laboratories within the Nuclear Weapon Complex. It is intended to foster cross-utilization of measurements between laboratories and provides a guide for survey and audit activities. Although this report was prepared by Sandia Primary Standards Laboratory (PSL), the PSL was intentionally omitted. Capabilities of the PSL are documented in SAND88-3402.UC-700.
Date: October 1, 1990
Creator: Romero, R.R. (ed.)
Object Type: Report
System: The UNT Digital Library
Proceedings of the first international workshop on accelerator alignment (open access)

Proceedings of the first international workshop on accelerator alignment

This report contains papers on the following accelerator topics: current alignment topics; toolboxes: instrumentation, software, and methods; fiducialization of conventional magnets; fiducialization of superconducting magnets; and next generation linear colliders.
Date: October 1, 1990
Creator: unknown
Object Type: Article
System: The UNT Digital Library
Optimal sensor fusion for land vehicle navigation (open access)

Optimal sensor fusion for land vehicle navigation

Position location is a fundamental requirement in autonomous mobile robots which record and subsequently follow x,y paths. The Dept. of Energy, Office of Safeguards and Security, Robotic Security Vehicle (RSV) program involves the development of an autonomous mobile robot for patrolling a structured exterior environment. A straight-forward method for autonomous path-following has been adopted and requires digitizing'' the desired road network by storing x,y coordinates every 2m along the roads. The position location system used to define the locations consists of a radio beacon system which triangulates position off two known transponders, and dead reckoning with compass and odometer. This paper addresses the problem of combining these two measurements to arrive at a best estimate of position. Two algorithms are proposed: the optimal'' algorithm treats the measurements as random variables and minimizes the estimate variance, while the average error'' algorithm considers the bias in dead reckoning and attempts to guarantee an average error. Data collected on the algorithms indicate that both work well in practice. 2 refs., 7 figs.
Date: October 1, 1990
Creator: Morrow, J. D.
Object Type: Report
System: The UNT Digital Library
An historical mullite fiber-reinforced ceramic composite: Characterization of the wootz' crucible refractory (open access)

An historical mullite fiber-reinforced ceramic composite: Characterization of the wootz' crucible refractory

Since at least the sixteenth century, the wootz'' ultra-high carbon white cast-iron ingot was produced in India by melting or carburising iron in a crucible. This ingot was forced into sword blades of so-called Damascus steel. The charged crucible was fired in a long (24-hour) single cycle at high temperature (1150-1250{degree}C) in a strongly reducing atmosphere. Raw materials for the refractory vessel are clay and coked'' rice husks. At high temperatures, two phases reinforce the glassy matrix: cristobalite relics of rice husks and a network of mullite crystals. This paper characterizes the microstructure and chemistry of the mullite network in the glassy matrix by means of a combination of techniques: optical microscopy, XRD, SEM, TEM and EDS, and HREM. 13 refs., 11 figs.
Date: October 1, 1990
Creator: Lowe, T.L. (California Univ., Berkeley, CA (USA)); Merk, N. & Thomas, G. (Lawrence Berkeley Lab., CA (USA))
Object Type: Article
System: The UNT Digital Library
Atmosphere control during preparation of YBa sub 2 Cu sub 3 O sub 7- x magnet windings (open access)

Atmosphere control during preparation of YBa sub 2 Cu sub 3 O sub 7- x magnet windings

Large coils of YBa{sub 2}Cu{sub 3}O{sub 7-x} can be fired successfully if the furnace atmosphere is carefully controlled. Organics added during processing produce CO{sub 2} during the initial portions of the firing schedule. Transmission electron microscopy of material fired in atmospheres containing various levels of CO{sub 2} clearly shows the extent of grain boundary degradation caused by CO{sub 2}. Coils with acceptable critical current density can be produced if the rate of CO{sub 2} removal is adequate. 9 refs., 4 figs., 1 tab.
Date: October 1, 1990
Creator: Poeppel, R. B.; Dorris, S. E.; Picciolo, J. J.; Balachandran, U.; Lanagan, M. T.; Zhang, C. Z. et al.
Object Type: Article
System: The UNT Digital Library
Solar reflector soiling pattern distributions and reflectance measurement requirements (open access)

Solar reflector soiling pattern distributions and reflectance measurement requirements

Short-term specular reflectance losses from optical surfaces used in the collection or concentration of solar energy results in significant reduction of these systems&#x27; output. Losses range from 0.1% to 1.0% per day, approaching asymptotes of 25% to 60% for periods greater than one year, depending onsite and season. To appropriately assess the value of a particular location for the production of power, consideration of the rates of soiling and strategies to minimize losses resulting from soiling must be considered. Strategies for measuring the optical performance of reflector materials to a specified degree of accuracy have been developed, according to the types of soiling patterns observed. It was found most soiling occurs with the accumulation of particulates in spots of different sizes, and the spot sizes follow a lognormal distribution. For most practical situations, it was determined that 10 measurements with a 1-cm-diameter beam are enough to place the average value within 3% of the true value, with a confidence level of 95%.
Date: October 1, 1990
Creator: Kidney, K. (Colorado Univ., Denver, CO (USA))
Object Type: Report
System: The UNT Digital Library