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Electricity Restructuring Background: Public Utility Holding Company Act of 1935 (PUHCA)
This report provides background information on PUHCA, including its history and impact. It also discusses how PUHCA reform fits into the current electric utility industry restructuring debate. This report will be updated as events warrant. For related information on electricity restructuring, see the CRS Electronic Briefing Book.
Date:
January 7, 1999
Creator:
Abel, Amy
Object Type:
Report
System:
The UNT Digital Library
Behavior of W and WSi(x) Contact Metallization on n- and p- Type GaN
Sputter-deposited W-based contacts on p-GaN (N{sub A} {approximately} 10{sup 18} cm{sup {minus}3}) display non-ohmic behavior independent of annealing temperature when measured at 25 C. The transition to ohmic behavior occurs above {approximately} 250 C as more of the acceptors become ionized. The optimum annealing temperature is {approximately} 700 C under these conditions. These contacts are much more thermally stable than the conventional Ni/Au metallization, which shows a severely degraded morphology even at 700 C. W-based contacts may be ohmic as-deposited on very heavily doped n-GaN, and the specific contact resistance improves with annealing up to {approximately} 900 C.
Date:
January 5, 1999
Creator:
Abernathy, C. R.; Cao, X. A.; Cole, M. W.; Eizenberg, M.; Lothian, J. R.; Pearton, S. J. et al.
Object Type:
Article
System:
The UNT Digital Library
Inductively Coupled Plasma Etching of III-Nitrides in Cl(2)/Xe,Cl(2)/Ar and Cl(2)/He
The role of additive noble gases He, Ar and Xe to C&based Inductively Coupled Plasmas for etching of GaN, AIN and InN were examined. The etch rates were a strong function of chlorine concentration, rf chuck power and ICP source power. The highest etch rates for InN were obtained with C12/Xe, while the highest rates for AIN and GaN were obtained with C12/He. Efficient breaking of the 111-nitrogen bond is crucial for attaining high etch rates. The InN etching was dominated by physical sputtering, in contrast to GaN and AIN. In the latter cases, the etch rates were limited by initial breaking of the III-nitrogen bond. Maximum selectivities of -80 for InN to GaN and InN to AIN were obtained.
Date:
January 5, 1999
Creator:
Abernathy, C.R.; Cho, H.; Donovan, S.M.; Hahn, Y.B.; Hays, D.C.; Jung, K.B. et al.
Object Type:
Article
System:
The UNT Digital Library
Depth Measurement of Moving Slurry at the Wet End of a Paper Machine
The paper industry has long had a need to better understand and control its papermaking process upstream, specifically at the wet end in the forming section of a paper machine. A vision-based system is under development that addresses this need by automatically measuring and interpreting the pertinent paper web parameters at the wet end in real time. The wet-end characterization of the paper web by a vision system involves a four-dimensional measurement of the slurry in real time. These measurements include the two-dimensional spatial information, the intensity profile, and the depth profile. This paper describes the real-time depth profile measurement system for the high-speed moving slurry. A laser line-based measurement method is used with a high-speed programmable camera to directly measure slurry height. The camera is programmed with a profile algorithm, producing depth data at fast sampling rates. Analysis and experimentation have been conducted to optimize the system for the characteristics of the slurry and laser line image. On-line experimental results are presented.
Date:
January 24, 1999
Creator:
Abidi, B. R.; Goddard, J. S., Jr.; Hunt, M. A.; Sari-Sarraf, H. & Turner, J. C.
Object Type:
Article
System:
The UNT Digital Library
[Abilene City Council Minutes: 1999]
Ledger containing minutes of the City Council in Abilene, Texas documenting the group's discussions and activities from January 14, 1999 to December 16, 1999.
Date:
1999-01-14/1999-12-16
Creator:
Abilene (Tex.)
Object Type:
Book
System:
The Portal to Texas History
Corrosion behavior of stainless steel-zirconium alloy waste forms.
Stainless steel-zirconium (SS-Zr) alloys are being considered as waste forms for the disposal of metallic waste generated during the electrometallurgical treatment of spent nuclear fuel. The baseline waste form for spent fuels from the EBR-II reactor is a stainless steel-15 wt.% zirconium (SS-15Zr) alloy. This article briefly reviews the microstructure of various SS-Zr waste form alloys and presents results of immersion corrosion and electrochemical corrosion tests performed on these alloys. The electrochemical tests show that the corrosion behavior of SS-Zr alloys is comparable to those of other alloys being considered for the Yucca Mountain geologic repository. The immersion tests demonstrate that the SS-Zr alloys are resistant to selective leaching of fission product elements and, hence, suitable as candidates for high-level nuclear waste forms.
Date:
January 13, 1999
Creator:
Abraham, D. P.
Object Type:
Article
System:
The UNT Digital Library
Natural Analogues of Nuclear Waste Glass Corrosion.
This report reviews and summarizes studies performed to characterize the products and processes involved in the corrosion of natural glasses. Studies are also reviewed and evaluated on how well the corrosion of natural glasses in natural environments serves as an analogue for the corrosion of high-level radioactive waste glasses in an engineered geologic disposal system. A wide range of natural and experimental corrosion studies has been performed on three major groups of natural glasses: tektite, obsidian, and basalt. Studies of the corrosion of natural glass attempt to characterize both the nature of alteration products and the reaction kinetics. Information available on natural glass was then compared to corresponding information on the corrosion of nuclear waste glasses, specifically to resolve two key questions: (1) whether one or more natural glasses behave similarly to nuclear waste glasses in laboratory tests, and (2) how these similarities can be used to support projections of the long-term corrosion of nuclear waste glasses. The corrosion behavior of basaltic glasses was most similar to that of nuclear waste glasses, but the corrosion of tektite and obsidian glasses involves certain processes that also occur during the corrosion of nuclear waste glasses. The reactions and processes that control basalt …
Date:
January 6, 1999
Creator:
Abrajano, T. A., Jr.; Ebert, W. L. & Luo, J. S.
Object Type:
Report
System:
The UNT Digital Library
Effects of Particulate Debris Morphology on the Rolling Wear Behavior of All-Steel and Si(Sub 3)N(Sub 4)-Steel Bearing Element Couples
Rolling contact fatigue experiments were performed on all-steel and hybrid Si{sub 3}N{sub 4}-M50 steel rolling bearing systems using particulate contaminated lubricants. The particulate contaminants used were glycothermally synthesized {alpha}-Al{sub 2}O{sub 3} platelets or Arizona test dust. The effects of contaminant composition and morphology on rolling contact fatigue and wear behavior were explored. The effects of bearing element material properties on fatigue and wear behavior were also examined. Rolling wear behavior is related to bearing component material configuration and the type of particulate contaminant present in the lubricant. Component and particulate material properties such as hardness and elastic modulus are observed to affect rolling wear behavior. Wear mechanisms such as contact stress fatigue, indenting, cutting and plowing are observed.
Date:
January 25, 1999
Creator:
Adair, J.H.; Mecholsky, J.J., Jr. & Mitchell, D.J.
Object Type:
Article
System:
The UNT Digital Library
Orientation imaging microscopy investigation of the compression deformation of a [011] ta single crystal
High-purity tantalum single crystal cylinders oriented with [110] parallel to the cylinder axis were deformed 10, 20, and 30 percent in compression. The samples were subsequently sectioned for characterization using Orientation Imaging Microscopy (O&I) along two orthogonal sectioning planes: one in the plane containing [001] and [110] (longitudinal) and the other in the plane containing [1{anti 1}0] and[110] (transverse). To examine local lattice rotations, the Euler angles relative to a reference angle at the section center were decomposed to their in-plane and out-of-plane components. The in-plane and out-of-plane misorientation maps for all compression tests reveal inhomogeneous deformation everywhere and particularly large lattice rotations in the comers of the longitudinal section. Of particular interest are the observed alternating orientation changes. This suggests the existence of networks of dislocations with net alternating sign that are required to accommodate the observed rotations. Rotation maps from the transverse section are distinctly different in appearance from those in the longitudinal plane. However, the rotation maps confirm that the rotations observed above were about the [1{anti 1}0] axis. Alternating orientation changes are also observed on this section. Results will be directly compared with crystal rotations predicted using finite element methods and reviewed in light of the …
Date:
January 8, 1999
Creator:
Adams, B L; Campbell, G H; King, W E; Lassila, D H; Stolken, J S; Sun, S et al.
Object Type:
Report
System:
The UNT Digital Library
Scanning Probe-Based Processes for Nanometer-Scale Device Fabrication
This is the final report of an LDRD program entitled 'Scanning Probe-Based Processes for Nanometer-Scale Device Fabrication'. This program intends to expand Sandia's expertise in scanning-probe based fabrication and characterization of nanostructures. Our object is to achieve an order of magnitude decrease in feature size compared to conventional fabrication technology. We are exploring approaches to nanostructure fabrication and characterization using scanning probe-based (STM, AFM). We also are developing numerical simulations of localized electric field and emission current to explore mechanisms and characterize limits to processing techniques. We emphasize novel fabrication processes and characterization of physical, chemical and electronic effects in nanostructures.
Date:
January 1, 1999
Creator:
Adams, D. P.; Houston, J. D.; Mayer, T. M. & Swartzentruber, B. S.
Object Type:
Report
System:
The UNT Digital Library
Tunable laser action at 4.0 microns from Fe:ZnSe
None
Date:
January 29, 1999
Creator:
Adams, J. J.; Page, R. H.; Bibeau, C. & Payne, S. A.
Object Type:
Article
System:
The UNT Digital Library
Experimental Investigation of In Situ Cleanable HEPA Filters
For the past several years studies have been conducted to investigate the use of innovative, alternative approaches to conventional disposable high efficiency particulate air filters.
Date:
January 7, 1999
Creator:
Adamson, D.J.
Object Type:
Report
System:
The UNT Digital Library
Heat Pipe Solar Receiver Development Activities at Sandia National Laboratories
Over the past decade, Sandia National Laboratories has been involved in the development of receivers to transfer energy from the focus of a parabolic dish concentrator to the heater tubes of a Stirling engine. Through the isothermal evaporation and condensation of sodium. a heat-pipe receiver can efficiently transfer energy to an engine's working fluid and compensate for irregularities in the flux distribution that is delivered by the concentrator. The operation of the heat pipe is completely passive because the liquid sodium is distributed over the solar-heated surface by capillary pumping provided by a wick structure. Tests have shown that using a heat pipe can boost the system performance by twenty percent when compared to directly illuminating the engine heater tubes. Designing heat pipe solar receivers has presented several challenges. The relatively large area ({approximately}0.2 m{sup 2}) of the receiver surface makes it difficult to design a wick that can continuously provide liquid sodium to all regions of the heated surface. Selecting a wick structure with smaller pores will improve capillary pumping capabilities of the wick, but the small pores will restrict the flow of liquid and generate high pressure drops. Selecting a wick that is comprised of very tine filaments …
Date:
January 8, 1999
Creator:
Adkins, D. R.; Andraka, C. E.; Moreno, J. B.; Moss, T. A.; Rawlinson, K. S. & Showalter, S. K.
Object Type:
Article
System:
The UNT Digital Library
Public Interest Obligations Advisory Committee Home Page
By Executive Order No. 13038, President Clinton established the Advisory Committee on Public Interest Obligations of Digital Television Broadcasters (PIAC). The Committee studied and recommended the public interest responsibilities that should accompany the broadcasters' receipt of digital television licenses. NTIA serves as the Secretariat for the Advisory Committee.
Date:
January 4, 1999
Creator:
Advisory Committee on Public Interest Obligations of Digital Television Broadcasters
Object Type:
Website
System:
The UNT Digital Library
Fuel processing for fuel cell powered vehicles.
A number of auto companies have announced plans to have fuel cell powered vehicles on the road by the year 2004. The low-temperature polymer electrolyte fuel cells to be used in these vehicles require high quality hydrogen. Without a hydrogen-refueling infrastructure, these vehicles need to convert the available hydrocarbon fuels into a hydrogen-rich gas on-board the vehicle. Earlier analysis has shown that fuel processors based on partial oxidation reforming are well suited to meet the size and weight targets and the other performance-related needs of on-board fuel processors for light-duty fuel cell vehicles (1).
Date:
January 22, 1999
Creator:
Ahmed, S.; Wilkenhoener, R.; Lee, S. H. D.; Carter, J. D.; Kumar, R. & Krumpelt, M.
Object Type:
Article
System:
The UNT Digital Library
Photoluminescence Studies of Lateral Composition Modulated Short-Period AlAs/InAs Superlattices
We present low temperature photoluminescence data for a series of spontaneous lateral composition modulation in (AlAs){sub m}/(InAs){sub n} short period superlattices on InP with differing average lattice constants, i.e., varying global strain. The low temperature photoluminescence peak energies were found to be much lower than the corresponding energy expected for the equivalent In{sub x}Al{sub 1{minus}x}As alloy. The bandgap energy reductions are found to approach 500 meV and this reduction is found to correlated with the strength of the composition modulation wave amplitude.
Date:
January 4, 1999
Creator:
Ahrenkiel, S. P.; Follstaedt, D. M.; Jones, E. D.; Lee, S. R.; Mascarenhas, A.; Mirecki-Millunchick, J. et al.
Object Type:
Article
System:
The UNT Digital Library
Phase Diagram of Iron, Revised-Core Temperatures
Shock-wave experiments on iron preheated to 1,573 K conducted from 14 to 73 GPa, yield new data for sound velocities of the {gamma}- and liquid-phases. Melting was observed in the highest pressure ({approximately} 71 {+-} 2 GPa) experiments at calculated shock temperatures of 2,775 {+-} 160 K. This single crossing of the {gamma}-liquid boundary measured here agrees closely with the {gamma}-iron melting line determined by Boehler [1993], Saxena et al. [1993], and Jephcoat and Besedin [1997]. This {gamma}-iron melting curve is {approximately} 300 C lower than that of Shen et al. [1998b] at 80 GPa.
Date:
January 27, 1999
Creator:
Ahrens, T.J.; Chen, G.Q. & Holland, K.G.
Object Type:
Article
System:
The UNT Digital Library
A Semiconductor Microlaser for Intracavity Flow Cytometry
Semiconductor microlasers are attractive components for micro-analysis systems because of their ability to emit coherent intense light from a small aperture. By using a surface-emitting semiconductor geometry, we were able to incorporate fluid flow inside a laser microcavity for the first time. This confers significant advantages for high throughput screening of cells, particulates and fluid analytes in a sensitive microdevice. In this paper we discuss the intracavity microfluidics and present preliminary results with flowing blood and brain cells.
Date:
January 20, 1999
Creator:
Akhil, O.; Copeland, G. C.; Dunne, J. L.; Gourley, P. L.; Hendricks, J. K. & McDonald, A. E.
Object Type:
Article
System:
The UNT Digital Library
Cyclization Phenomena in the Sol-Gel Polymerization of a,w-Bis(triethoxysilyl)alkanes and Incorporation of the Cyclic Structures into Network Silsesquioxane Polymers
Intramolecular cyclizations during acid-catalyzed, sol-gel polymerizations of ct,co- bis(tietioxysilyl)aWmes substintidly lengtien gelties formonomers witietiylene- (l), propylene- (2), and butylene-(3)-bridging groups. These cyclizations reactions were found, using mass spectrometry and %i NMR spectroscopy, to lead preferentially to monomeric and dimeric products based on six and seven membered disilsesquioxane rings. 1,2- Bis(triethoxysilyl)ethane (1) reacts under acidic conditions to give a bicyclic drier (5) that is composed of two annelated seven membered rings. Under the same conditions, 1,3- bis(triethoxysilyl)propane (2), 1,4-bis(triethoxysilyl)butane (3), and z-1,4- bis(triethoxysilyl)but-2-ene (10) undergo an intramolecular condensation reaction to give the six membemd and seven membered cyclic disilsesquioxanes 6, 7, and 11. Subsequently, these cyclic monomers slowly react to form the tricyclic dirners 8,9 and 12. With NaOH as polymerization catalyst these cyclic silsesquioxanes readily ~aeted to afford gels that were shown by CP MAS z%i NMR and infr=d spectroscopes to retain some cyclic structures. Comparison of the porosity and microstructwe of xerogels prepared from the cyclic monomers 6 and 7 with gels prepared directly from their acyclic precursors 2 and 3, indicate that the final pore structure of the xerogels is markedly dependent on the nature of the precursor. In addition, despite the fact that the monomeric cyclic disilsesquioxane …
Date:
January 4, 1999
Creator:
Alam, T.M.; Carpenter, J.P.; Dorhout, P.K.; Greaves, J.; Loy, D.A.; Shaltout, R. et al.
Object Type:
Article
System:
The UNT Digital Library
Fishing Gear/Sea Floor Impacts Workshop : AFSC, January 27-28 1999
This document contains the daily presentation schedule, presenter information, and attendee list for a Fishing Gear/Sea Floor Impacts Workshop that took place from January 27-28, 1999 at the Alaska Fisheries Science Center.
Date:
January 1999
Creator:
Alaska Fisheries Science Center
Object Type:
Text
System:
The UNT Digital Library
Functions and Requirements for Russian Pulsating Monitor Deployment in the Gunite and Associated Tanks at Oak Ridge National Laboratory
This document provides functions and requirements to support deployment of pulsating mixer pump technology in the Oak Ridge National Laboratory (ORNL) Gunite and Associated Tanks to mobilize and mix the settled sludge and solids in these tanks. In FY 1998 pulsating mixer pump technology, a jet mixer powered by a reciprocating air supply, was selected for FY 1999 deployment in one of the GAAT tanks to mobilize settled solids. Pulsating mixer pump technology was identified in FY 1996 during technical exchanges between the US Department of Energy (DOE) Tanks Focus Area Retrieval and Closure program, the DOE Environmental Management International Programs, and delegates from Russia as a promising technology that could be implemented in the US. The pulsating mixer pump technology, provided by the Russian Integrated Mining Chemical Company, was tested at Pacific Northwest National Laboratory (PNNL) to observe its ability to mobilize settled solids. Based on the results of this demonstration, ORNL and DOE staff determined that a modified pulsating mixer pump would meet project needs for bulk mobilization of Gunite tank sludge prior to deployment of other retrieval systems. The deployment of this device is expected to significantly reduce the costs of operation and maintenance of more expensive …
Date:
January 1999
Creator:
Albert, Thomas
Object Type:
Report
System:
The UNT Digital Library
Optical sensors for process control and emissions monitoring in industry
Sandia National Laboratories has a number of ongoing projects developing optical sensors for industrial environments. Laser-based sensors can be attractive for relatively harsh environments where extractive sampling is difficult, inaccurate, or impractical. Tools developed primarily for laboratory research can often be adapted for the real world and applied to problems far from their original uses. Spectroscopic techniques, appropriately selected, have the potential to impact the bottom line of a number of industries and industrial processes. In this paper the authors discuss three such applications: a laser-based instrument for process control in steelmaking, a laser-induced breakdown method for hazardous metal detection in process streams, and a laser-based imaging sensor for evaluating surface cleanliness. Each has the potential to provide critical, process-related information in a real-time, continuous manner. These sensor techniques encompass process control applications and emissions monitoring for pollution prevention. They also span the range from a field-tested pre-commercial prototype to laboratory instrumentation. Finally, these sensors employ a wide range of sophistication in both the laser source and associated analytical spectroscopy. In the ultimate applications, however, many attributes of the sensors are in common, such as the need for robust operation and hardening for harsh industrial environments.
Date:
January 1, 1999
Creator:
Alendorf, S. W.; Ottensen, D. K.; Hahn, D. W.; Kulp, T. J. & Goers, U. B.
Object Type:
Report
System:
The UNT Digital Library
Oral History Interview with Howard L. Patton, January 5, 1999
Access:
Use of this item is restricted to the UNT Community
Interview with Howard L. Patton, a Army WWII veteran from Flora, Illinois. Patton discusses his family background, commissioning into the Army through ROTC, training with anti-air artillery, his marriage, deployment to New Guinea, the assault on Wakde Island, the battle of Leyte, operations at Zamboanga, and the end of the war.
Date:
January 5, 1999
Creator:
Alexander, William J. & Patton, Howard L.
Object Type:
Book
System:
The UNT Digital Library
Subsurface imaging using the spectral polarization difference technique and NIR illumination
A subsurface imaging system is utilized to test the ability of the spectral polarization difference imaging technique for deep subsurface imaging in tissues. The illumination of the system is derived from compact class III lasers in the red and NIR spectral region and, alternatively, from a white light source and selection of the appropriate illumination wavelength using band-pass optical filters. The experimental results demonstrate detection and imaging of a high-scattering object located up to 1.5 cm underneath the surface of a host chicken tissue.
Date:
January 26, 1999
Creator:
Alfano, R R; Demos, S G & Radousky, H B
Object Type:
Article
System:
The UNT Digital Library