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Analysis of Failed Nuclear Plant Components (open access)

Analysis of Failed Nuclear Plant Components

Argonne National Laboratory has conducted analyses of failed components from nuclear power generating stations since 1974. The considerations involved in working with and analyzing radioactive components are reviewed here, and the decontamination of these components is discussed. Analyses of four failed components from nuclear plants are then described to illustrate the kinds of failures seen in service. The failures discussed are (a) intergranular stress corrosion cracking of core spray injection piping in a boiling water reactor, (b) failure of canopy seal welds in adapter tube assemblies in the control rod drive head of a pressure water reactor, (c) thermal fatigue of a recirculation pump shaft in a boiling water reactor, and (d) failure of pump seal wear rings by nickel leaching in a boiling water reactor.
Date: July 1, 1992
Creator: Diercks, D. R.
System: The UNT Digital Library
X-ray microscopy resource center at the Advanced Light Source (open access)

X-ray microscopy resource center at the Advanced Light Source

An x-ray microscopy resource center for biological x-ray imaging vvill be built at the Advanced Light Source (ALS) in Berkeley. The unique high brightness of the ALS allows short exposure times and high image quality. Two microscopes, an x-ray microscope (XM) and a scanning x-ray microscope (SXM) are planned. These microscopes serve complementary needs. The XM gives images in parallel at comparable short exposure times, and the SXM is optimized for low radiation doses applied to the sample. The microscopes extend visible light microscopy towards significantly higher resolution and permit images of objects in an aqueous medium. High resolution is accomplished by the use of Fresnel zone plates. Design considerations to serve the needs of biological x-ray microscopy are given. Also the preliminary design of the microscopes is presented. Multiple wavelength and multiple view images will provide elemental contrast and some degree of 3D information.
Date: July 1, 1992
Creator: Meyer-Ilse, W.; Koike, M.; Beguiristain, R.; Maser, J. & Attwood, D.
System: The UNT Digital Library
Air exchange effectiveness in office buildings: Measurement techniques and results (open access)

Air exchange effectiveness in office buildings: Measurement techniques and results

We define two air exchange effectiveness parameters which indicate the extent of short circuiting, mixing, or displacement air flow in an entire building, the air diffusion effectiveness which indicates the air flow pattern locally, and the normalized local age of air. After describing two tracer gas procedures for measuring these parameters, we discuss assumptions inherent in the data analysis that are often violated in large office buildings. To obtain valuable data, careful selection of buildings for measurements and assessments to determine if operating conditions are reasonably consistent with the assumptions are necessary. Multiple factors, in addition to the air flow pattern in the occupied space, can affect measurement results, consequently, the interpretation of measurements is not straightforward. We summarize the results of measurements in several office buildings and in a research laboratory. Almost all measurements indicate that the extent of both short circuiting and displacement flow is small. A moderate amount of short circuiting is evident from a few measurements in rooms with heated supply air. Ages of air and their reciprocals (local ventilation rates) often vary substantially between rooms, probably because of room-to-room variation in the rate of air supply. For future research, we suggest assessments of measurement accuracy, …
Date: July 1, 1992
Creator: Fisk, W.J. & Faulkner, D.
System: The UNT Digital Library
ILSE: The next step toward a heavy ion induction accelerator for inertial fusion energy (open access)

ILSE: The next step toward a heavy ion induction accelerator for inertial fusion energy

LBL and LLNL propose to build, at LBL, the Induction Linac Systems Experiments (ILSE), the next logical step towards the eventual goal of a heavy-ion induction accelerator powerful enough to implode or drive'' inertial-confinement fusion targets. ILSE, although much smaller than a driver, will be the first experiment at full driver scale in several important parameters. Most notable among these are line charge density and beam cross section. Many other accelerator components and beam manipulations needed for an inertial fusion energy (IFE) driver will be tested. The ILSE accelerator and research program will permit experimental study of those beam manipulations required of an induction linac inertial fusion driver which have not been tested sufficiently in previous experiments, and will provide a step toward driver technology.
Date: July 1, 1992
Creator: Fessenden, T.; Bangerter, R.; Berners, D.; Chew, J.; Eylon, S.; Faltens, A. et al.
System: The UNT Digital Library
Investigation of PACVD protective coating processes using advanced diagnostics techniques (open access)

Investigation of PACVD protective coating processes using advanced diagnostics techniques

Coherent anti-Stokes Raman Spectroscopy (CARS) is used to study the plasma-assisted chemical vapor deposition (PACVD) of TiB{sub 2}. CARS is applied to the dominent species in an inductively coupled B{sub 2}H{sub 6}/Ar rf plasma. Axial concentration profiles of diborane and hydrogen are probed in the plasma. A five-step mechanism is developed. Photochemical initiation of the chemical reaction is considered. 16 refs, 5 figs.(DLC)
Date: July 10, 1992
Creator: Roman, W.C.
System: The UNT Digital Library
Performance of the LBL AECR source at various frequencies (open access)

Performance of the LBL AECR source at various frequencies

To study the effects of frequency on an electron cyclotron resonance (ECR) ion source, the LBL Advanced ECR ion source (designed to operate at 14 GHz) has been tested at 6.4, 10, and 14 GHz with one plasma chamber (ID = 6.0 cm), a permanent sextuple magnet ( closed sextuple'') with a field strength of 0.84 Tesla at the chamber wall, and no radial vacuum pumping. Pure oxygen was used as the running gas for a fair comparison. The source was tested as a single stage, as well as with cold electron injection using an electron gun in place of a conventional microwave-driven first stage. Higher frequency, with a higher axial magnetic field to ensure a closed ECR zone for electron heating, does give better performance. As demonstrated before, at each frequency electron injection led to about a factor of two increase in the high charge state oxygen beam intensity. The 14 GHz performance of the AECR source with the closed sextuple magnet was compared to the slotted sextuple'' (a plasma chamber with radial pumping slots of 7.0-cm dia and a weaker magnet of 0.64 Tesla at the chamber wall). Results show that a stronger sextuple magnet alone does not …
Date: July 1, 1992
Creator: Xie, Z.Q.; Lyneis, C.M.; Lundgren, S.A. & Collins, D.
System: The UNT Digital Library
An overview of reactor physics standards: Past, present and future (open access)

An overview of reactor physics standards: Past, present and future

This report discusses for determining key static reactor physics parameters which have been developed by groups of experts (working groups) under the aegis of ANS-19, the ANS Reactor Physics Standards Committee. Following a series of sequential reviews, augmented by feedback from potential users, a proposed standard is brought into final form by the working group before it is adopted as a formal standard by the American National Standards Institute (ANSI); Reactor Physics standards are intended to provide guidance in the performance and qualification of complex sequences of reactor calculations and/or measurements and are regularly reviewed for possible updates and/or revisions. The reactor physics standards developed to date are listed and standards now being developed by the respective working groups are also provided.
Date: July 1, 1992
Creator: Cokinos, D.M.
System: The UNT Digital Library
Damping the. pi. -mode instability in the SLC damping rings with a passive cavity (open access)

Damping the. pi. -mode instability in the SLC damping rings with a passive cavity

Operating the Stanford Linear Collider (SLC) at 120Hz repetition rate requires the presence of two bunches in both the electron and the positron damping ring. The {pi}-mode instability, a coupled bunch instability where the two bunches oscillate with a phase difference of 180{degrees}, had been observed in both rings with low current thresholds of 7{sup *}10{sup 9} particles per bunch. To avoid the instability, the RF system had to be operated in ways which in general reduced the cavity gap voltages and required constant operational attention. For the 1992 running cycle a passive cavity was installed and successfully tested. It is tuned to the frequency of the lower synchrotron oscillation sideband of an odd revolution harmonic. The impedance of the cavity then damps {pi}-mode oscillations very similar to the Robinson damping provided by the main RF cavities which damps O-mode synchrotron oscillations. In this report we describe the motivation and physical considerations that led to the final design parameters and the experience obtained from the performance of these cavities.
Date: July 1, 1992
Creator: Chao, Y.; Corredoura, P.; Hill, A.; Krejcik, P.; Limberg, T.; Minty, M. et al.
System: The UNT Digital Library
Fourier transform ion cyclotron resonance precision atomic mass measurement limits (open access)

Fourier transform ion cyclotron resonance precision atomic mass measurement limits

The application of Fourier Transform Ion Cylcotron Resonance Mass Spectroscopy to precision atomic mass measurements is considered. Limits on the mass accuracy of this technique for atomic masses are discussed, and plans for future developments with application to fundamental weak interaction physics are presented.
Date: July 1, 1992
Creator: Kouzes, R.T.
System: The UNT Digital Library
Integrated envelope and lighting technologies for commercial buildings (open access)

Integrated envelope and lighting technologies for commercial buildings

Fenestration systems are major contributors to peak cooling loads in commercial buildings and thus to HVAC system costs, peak electric demand, and annual energy use. These loads can be reduced significantly through proper fenestration design and the use of daylighting strategies. However, there are very few documented applications of energy-saving daylighted buildings today, which suggests that significant obstacles to efficient fenestration and lighting design and utilization still exist. This paper reports results of the first phase of a utility-sponsored research, development, and demonstration project to more effectively address the interrelated issues of designing and implementing energy-efficient envelope and lighting systems. We hypothesize that daylighting and overall energy efficiency will not be achieved at a large scale until true building integration has been accomplished to some meaningful degree. Moving beyond the vague concept of intelligent' buildings long popular in the design sector, we attempt to integrate component technologies into functional systems in order to optimize the relevant building energy performance and occupant comfort parameters. We describe the first set of integrated envelope and lighting concepts we are developing using available component technologies. Emerging and future technologies will be incorporated in later phases. Because new hardware systems alone will not ensure optimal …
Date: July 1, 1992
Creator: Selkowitz, S. & Schuman, J.
System: The UNT Digital Library
On canonical cylinder sections for accurate determination of contact angle in microgravity (open access)

On canonical cylinder sections for accurate determination of contact angle in microgravity

Large shifts of liquid arising from small changes in certain container shapes in zero gravity can be used as a basis for accurately determining contact angle. Canonical'' geometries for this purpose, recently developed mathematically, are investigated here computationally. It is found that the desired nearly- discontinuous'' behavior can be obtained and that the shifts of liquid have sufficient volume to be readily observed.
Date: July 1, 1992
Creator: Concus, P.; Zabihi, F. (Lawrence Berkeley Lab., CA (United States) California Univ., Berkeley, CA (United States). Dept. of Mathematics) & Finn, R. (Stanford Univ., CA (United States). Dept. of Mathematics)
System: The UNT Digital Library
The potential effects of concurrent increases in temperature, CO sub 2 and O sub 3 on net photosynthesis, as mediated by rubisCO (open access)

The potential effects of concurrent increases in temperature, CO sub 2 and O sub 3 on net photosynthesis, as mediated by rubisCO

At the leaf level, under light saturating and light limiting conditions, it is shown that elevated atmospheric CO{sub 2} concentration not only alters the scale of the response of carbon gain to rising temperature, but can alter the direction of response. These points bring into serious question the value of any predictions of plant production which ignore not only the direct effect Of C0{sub 2} on carbon gain, but also the basic interactions of temperature, C0{sub 2} and 0{sub 3}. Whilst many factors may potentially diminish the enhancement of lightsaturated leaf photosynthetic rates with increase in atmospheric CO{sub 2} concentrations, no mechanism has so far been identified which could remove the parallel stimulation of light-limited photosynthesis.
Date: July 1, 1992
Creator: Long, S. (Brookhaven National Lab., Upton, NY (United States) Essex Univ., Colchester (United Kingdom). Dept. of Biology)
System: The UNT Digital Library
Reducing bunch disruption in transition crossing by modification of the rf waveform (open access)

Reducing bunch disruption in transition crossing by modification of the rf waveform

We investigate the utility of accelerating during the nonadiabatic period surrounding the time of transition with an rf waveform modified by a second or third harmonic component to eliminate rf focusing. Simulation study shows this scheme not only to control momentum spread but also to have apparent advantage with respect to microwave instability. An experimental test has been initiated in the Fermilab Main Ring using a cavity at the third harmonic of the rf.
Date: July 1, 1992
Creator: MacLachlan, J.; Griffin, J.; Crawford, C.; Wildman, D.; Bhat, C. & Martens, M.
System: The UNT Digital Library
Oxygen diffusion in high- Tc superconductors (open access)

Oxygen diffusion in high- Tc superconductors

The cuprate superconductors are fascinating not only because of their technical promise, but also because of their structures, especially the anisotropy of the crystal lattice. There are some structural similarities among these compounds, but also significant differences. Measurements of the oxygen tracer diffusion coefficients have been carried out as a function of temperature, oxygen partial pressure, crystal orientation, and doping in the La-Sr-Cu-0, Y-Ba-Cu-0, and Bi-Sr-Ca-Cu-0 systems. These measurements have revealed a variety of defect mechanisms operating in these compounds; the exact nature of the mechanism depends on the details of the structure.
Date: July 1, 1992
Creator: Rothman, S. J. & Routbort, J. L.
System: The UNT Digital Library
Thirteenth international conference on cyclotrons and their applications (open access)

Thirteenth international conference on cyclotrons and their applications

This report contains short descriptions of papers presented at the Thirteenth International Conference on Cyclotrons and Their Applications.
Date: July 1, 1992
Creator: Clark, D. J.
System: The UNT Digital Library
Exclusive two-photon processes: Tests of QCD at the amplitude level (open access)

Exclusive two-photon processes: Tests of QCD at the amplitude level

Exclusive two-photon processes at large momentum transfer, particularly Compton scattering {gamma}p{yields}{gamma}p and its crossed-channel reactions {gamma}{gamma}{yields}{bar p}p and {bar p}p{yields}{gamma}{gamma}, can provide definitive information on the bound-state distributions of quarks in hadrons at the amplitude level. Recent theoretical work has shown that QCD predictions based on the factorization of long and short distance physics are already applicable at momentum transfers of order of a few GeV.
Date: July 1, 1992
Creator: Brodsky, Stanley J.
System: The UNT Digital Library
[Fort Worth Star-Telegram article, July 1, 1992] (open access)

[Fort Worth Star-Telegram article, July 1, 1992]

An article written by Martha Deller for the Fort Worth Star-Telegram about the NTIEVA program and its work in schools in the DFW Metroplex.
Date: July 1, 1992
Creator: Deller, Martha
System: The UNT Digital Library
Low-temperature specific heat of YMn sub 2 in the paramagnetic and antiferromagnetic phases (open access)

Low-temperature specific heat of YMn sub 2 in the paramagnetic and antiferromagnetic phases

The low-temperature specific heat of YMn{sub 2} has been measured at applied pressures of 0 to 7.7 kbar. A paramagnetic state is stabilized for moderate values of the applied pressure (of the order of 1.6 kbar). A large linear term in the specific heat, which decreases regularly with increasing pressure, is observed in this phase. It is ascribed to giant spin fluctuations associated with a magnetic-non magnetic instability and a strong geometrical spin frustration.
Date: July 1, 1992
Creator: Fisher, R. A.; Emerson, J. P.; Phillips, N. E. (Lawrence Berkeley Lab., CA (United States)); Ballou, R. & Lelievre-Berna, E. (Centre National de la Recherche Scientifique (CNRS), 38 - Grenoble (France). Lab. Louis Neel)
System: The UNT Digital Library
Ion sources for cyclotron applications (open access)

Ion sources for cyclotron applications

The use of a multicusp plasma generator as an ion source has many advantages. The development of both positive and negative ion beams based on the multicusp source geometry is presented. It is shown that these sources can be operated at steady state or cw mode. As a result they are very suitable for cyclotron operations.
Date: July 1, 1992
Creator: Leung, K. N.; Bachman, D. A.; McDonald, D. S. & Young, A. T.
System: The UNT Digital Library
XUV synchrotron optical components for the Advanced Light Source: Summary of the requirements and the developmental program (open access)

XUV synchrotron optical components for the Advanced Light Source: Summary of the requirements and the developmental program

We give a brief summary of the requirements for water cooled optical components for the Advanced Light Source (ALS), a third generation synchrotron radiation source under construction at Lawrence Berkeley Laboratory (LBL). Materials choices, surface figure and smoothness specifications, and metrology systems for measuring the plated metal surfaces are discussed. Results from a finished water cooled copper alloy mirror will be used to demonstrate the state of the art in optical metrology with the Takacs Long Trace Profiler (LTP II).
Date: July 1, 1992
Creator: McKinney, W.; Irick, S. & Lunt, D.
System: The UNT Digital Library
Thireenth international conference on cyclotrons and their applications. Conference summary (open access)

Thireenth international conference on cyclotrons and their applications. Conference summary

This report contains short descriptions of papers presented at the Thirteenth International Conference on Cyclotrons and Their Applications.
Date: July 1, 1992
Creator: Clark, D. J.
System: The UNT Digital Library
Reducing bunch disruption in transition crossing by modification of the rf waveform (open access)

Reducing bunch disruption in transition crossing by modification of the rf waveform

We investigate the utility of accelerating during the nonadiabatic period surrounding the time of transition with an rf waveform modified by a second or third harmonic component to eliminate rf focusing. Simulation study shows this scheme not only to control momentum spread but also to have apparent advantage with respect to microwave instability. An experimental test has been initiated in the Fermilab Main Ring using a cavity at the third harmonic of the rf.
Date: July 1, 1992
Creator: MacLachlan, J.; Griffin, J.; Crawford, C.; Wildman, D.; Bhat, C. & Martens, M.
System: The UNT Digital Library
Air exchange effectiveness in office buildings: Measurement techniques and results (open access)

Air exchange effectiveness in office buildings: Measurement techniques and results

We define two air exchange effectiveness parameters which indicate the extent of short circuiting, mixing, or displacement air flow in an entire building, the air diffusion effectiveness which indicates the air flow pattern locally, and the normalized local age of air. After describing two tracer gas procedures for measuring these parameters, we discuss assumptions inherent in the data analysis that are often violated in large office buildings. To obtain valuable data, careful selection of buildings for measurements and assessments to determine if operating conditions are reasonably consistent with the assumptions are necessary. Multiple factors, in addition to the air flow pattern in the occupied space, can affect measurement results, consequently, the interpretation of measurements is not straightforward. We summarize the results of measurements in several office buildings and in a research laboratory. Almost all measurements indicate that the extent of both short circuiting and displacement flow is small. A moderate amount of short circuiting is evident from a few measurements in rooms with heated supply air. Ages of air and their reciprocals (local ventilation rates) often vary substantially between rooms, probably because of room-to-room variation in the rate of air supply. For future research, we suggest assessments of measurement accuracy, …
Date: July 1, 1992
Creator: Fisk, W. J. & Faulkner, D.
System: The UNT Digital Library
Use of GRASS for routing gas pipeline rights-of-way (open access)

Use of GRASS for routing gas pipeline rights-of-way

This study, sponsored by the Gas Research Institute (GRI), was conducted to illustrate how a GIS (Geographic Information System) can be used to assess alternative routes for new gas pipeline rights-of-way (ROWs). The results show that a least-cost analysis using GRASS (Geographic Resources Analysis and Support System) is a good method for siting new gas pipeline ROWs on the basis of environmental and engineering constraints to pipeline construction and maintenance. The cost and time needed to use this least-cost approach compare favorably with the current methods used by gas pipeline company planners and engineers. The types of criteria used, as well as the costs or weights given to the criteria, can be changed easily. This provides the flexibility to assess several alternatives quickly and easily.
Date: July 1, 1992
Creator: Sydelko, P. J.
System: The UNT Digital Library