New K Reactor aluminum HCR: Temperature study (open access)

New K Reactor aluminum HCR: Temperature study

Recent (HCR) Horizonal Control Rod operating problems at the K Reactors, caused primarily by graphite stack distortion, have stimulated several designs of HCR`s capable of operating under adverse conditions. One such design is an aluminum HCR, not completely dissimilar to the present HCR`s, conceived by the Research and Engineering Operation of I.P.D. The successful use of aluminum as a structural material is strongly dependent upon the operating temperature of the aluminum. This study was conducted to determine anticipated operating temperatures of the HCR during reactor operation at the present K Reactor conditions.
Date: February 17, 1964
Creator: Agar, J. D.
Object Type: Report
System: The UNT Digital Library
Surface roughness effects on the solar reflectance of cool asphalt shingles (open access)

Surface roughness effects on the solar reflectance of cool asphalt shingles

We analyze the solar reflectance of asphalt roofing shingles that are covered with pigmented mineral roofing granules. The reflecting surface is rough, with a total area approximately twice the nominal area. We introduce a simple analytical model that relates the 'micro-reflectance' of a small surface region to the 'macro-reflectance' of the shingle. This model uses a mean field approximation to account for multiple scattering effects. The model is then used to compute the reflectance of shingles with a mixture of different colored granules, when the reflectances of the corresponding mono-color shingles are known. Simple linear averaging works well, with small corrections to linear averaging derived for highly reflective materials. Reflective base granules and reflective surface coatings aid achievement of high solar reflectance. Other factors that influence the solar reflectance are the size distribution of the granules, coverage of the asphalt substrate, and orientation of the granules as affected by rollers during fabrication.
Date: February 17, 2008
Creator: Akbari, Hashem; Berdahl, Paul; Akbari, Hashem; Jacobs, Jeffry & Klink, Frank
Object Type: Article
System: The UNT Digital Library
Initial Experience to Determine the Solubility of Salts in Low-Level Mix Waste Glasses (open access)

Initial Experience to Determine the Solubility of Salts in Low-Level Mix Waste Glasses

Glass may be used to immobilize low-level mixed waste (LLMW) at the Savannah River Site because of its ability to accept a wide variety of components into its network structure. However, many common salts (sulfates, chlorides, phosphates, and chromates) present in the LLMW streams have limited solubility in glass. Processing and product problems may arise if the solubility of these salts is exceeded. In an effort to determine the factors that most affect salt solubilities, a statistical screening experiment was performed. The screening experiment, a Plackett-Burman design, allowed efficient estimation of the effects of variables, such as the composition of the glass, the temperature of the melt, the duration of melting, and the cooling rate. Each of these factors, along with a combination of sulfate, chloride, phosphate and chromate concentrations, were examined to provide an estimate of the solubility of each salt. The results of the screening experiment were interpreted to determine which variables should be further examined. The composition of the glass, especially the concentrations of boron, calcium and the alkalis, was found to have the greatest effect on the solubilities of the salts. This paper will discuss the results of the screening experiment and describe a path forward.
Date: February 17, 1995
Creator: Andrews, M.K. & Saur, C.C.
Object Type: Article
System: The UNT Digital Library
Dose potential of sludge contaminated and/or TRU contaminated waste in B-25s for tornado and straight wind events (open access)

Dose potential of sludge contaminated and/or TRU contaminated waste in B-25s for tornado and straight wind events

F and H Tank Farms generate supernate and sludge contaminated Low-Level Waste. The waste is collected, characterized, and packaged for disposal. Before the waste can be disposed of, however, it must be properly characterized. Since the radionuclide distribution in typical supernate is well known, its characterization is relatively straight forward and requires minimal effort. Non-routine waste, including potentially sludge contaminated, requires much more effort to effectively characterize. The radionuclide distribution must be determined. In some cases the waste can be contaminated by various sludge transfers with unique radionuclide distributions. In these cases, the characterization can require an extensive effort. Even after an extensive characterization effort, the container must still be prepared for shipping. Therefore a significant amount of time may elapse from the time the waste is generated until the time of disposal. During the time it is possible for a tornado or high wind scenario to occur. The purpose of this report is to determine the effect of a tornado on potential sludge contaminated waste, or Transuranic (TRU) waste in B-25s [large storage containers], to evaluate the potential impact on F and H Tank Farms, and to help establish a B-25 control program for tornado events.
Date: February 17, 2000
Creator: Aponte, C.I.
Object Type: Report
System: The UNT Digital Library
Cretaceous shallow drilling, US Western Interior: Core research. Technical progress report (open access)

Cretaceous shallow drilling, US Western Interior: Core research. Technical progress report

This project is a continuing multidisciplinary study of middle to Upper Cretaceous marine carbonate and clastic rocks in the Utah-Colorado-Kansas corridor of the old Cretaceous seaway that extended from the Gulf Coast to the Arctic during maximum Cretaceous transgressions. It is collaborative between in the US Geological Survey (W.E. Dean, P.I.) and University researchers led by The Pennsylvania State University(M.A. Arthur, P.I.) and funded by DOE and the USGS, in part. Research focusses on the Greenhom, Niobrara and lower Pierre Shale units and their equivalents, combining biostratigraphic/paleoecologic studies, inorganic, organic and stable isotopic geochemical studies, mineralogical investigations and high-resolution geophysical logging. This research requires unweathered samples and continuous smooth ``exposures`` in the form of cores from at least 4 relatively shallow reference holes (i.e. < 1000m) in transect from east to west across the basin. The major initial effort was recovery in Year 1 of the project of continuous cores from each site in the transect. This drilling provided samples and logs of strata ranging from pelagic sequences that contain organic-carbon-rich marine source rocks to nearshore coal-bearing units. This transect also will provide information on the extent of thermal maturation and migration of hydrocarbons in organic-carbon-rich strata along a burial …
Date: February 17, 1993
Creator: Arthur, M. A.
Object Type: Report
System: The UNT Digital Library
Cretaceous shallow drilling, US Western Interior: Core research (open access)

Cretaceous shallow drilling, US Western Interior: Core research

This project is a continuing multidisciplinary study of middle to Upper Cretaceous marine carbonate and clastic rocks in the Utah-Colorado-Kansas corridor of the old Cretaceous seaway that extended from the Gulf Coast to the Arctic during maximum Cretaceous transgressions. It is collaborative between in the US Geological Survey (W.E. Dean, P.I.) and University researchers led by The Pennsylvania State University(M.A. Arthur, P.I.) and funded by DOE and the USGS, in part. Research focusses on the Greenhom, Niobrara and lower Pierre Shale units and their equivalents, combining biostratigraphic/paleoecologic studies, inorganic, organic and stable isotopic geochemical studies, mineralogical investigations and high-resolution geophysical logging. This research requires unweathered samples and continuous smooth exposures'' in the form of cores from at least 4 relatively shallow reference holes (i.e. < 1000m) in transect from east to west across the basin. The major initial effort was recovery in Year 1 of the project of continuous cores from each site in the transect. This drilling provided samples and logs of strata ranging from pelagic sequences that contain organic-carbon-rich marine source rocks to nearshore coal-bearing units. This transect also will provide information on the extent of thermal maturation and migration of hydrocarbons in organic-carbon-rich strata along a burial …
Date: February 17, 1993
Creator: Arthur, Michael A.
Object Type: Report
System: The UNT Digital Library
Melt processing of Yb-123 tapes (open access)

Melt processing of Yb-123 tapes

The innovation of a simple, scalable process for manufacturing long-length conductors of HTS is essential to potential commercial applications such as power cables, magnets, and transformers. In this paper the authors demonstrate that melt processing of Yb-123 tapes made by the PIT route is an alternative to the coated conductor and Bi-2223 PIT tape fabrication techniques. Ag-clad Yb-123 tapes were fabricated by groove rolling and subsequently, melt processed in different oxygen partial pressures in a zone-melting furnace with a gradient of 140 C/cm. The transition temperatures measured were found to be around 81 K undermost processing conditions. EPMA of the tapes processed under different conditions show the 123 phase to be Ba deficient and Cu and Yb rich. Critical current was measured at various temperatures from 77 K to 4.2 K. The J{sub c} increased with decrease in pO{sub 2}. The highest I{sub c} obtained was 52 A at 4.2 K.
Date: February 17, 2000
Creator: Athur, S. P.; Balachandran, U. & Salama, K.
Object Type: Article
System: The UNT Digital Library
In-plane quasi-particle tunneling into Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8} (open access)

In-plane quasi-particle tunneling into Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8}

Planar tunneling spectroscopy is performed into the a-b plane of the high-temperature superconductor Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8}. The tunneling spectra exhibit a zero-bias conductance peak (ZBCP). Preliminary studies as a function of temperature, crystallographic orientation, magnetic field magnitude and direction confirm the ZBCP is an Andreev bound state (ABS) at zero energy. Below 5K, a depletion in the density of states at zero energy is observed.
Date: February 17, 2000
Creator: Aubin, H.; Pugel, D. E.; Badica, E.; Greene, L. H.; Jian, S. & Hinks, D. G.
Object Type: Article
System: The UNT Digital Library
User Manual for the AZ-101 Data Acquisition System (AS-101 DAS) (open access)

User Manual for the AZ-101 Data Acquisition System (AS-101 DAS)

User manual for the TK AZ-101 Waste Retrieval System Data Acquisition System. The purpose of this document is to describe use of the AZ-101 Data Acquisition System (AZ-101 DAS). The AZ-101 DAS is provided to fulfill the requirements for data collection and monitoring as defined in Letters of Instruction (LOI) from Numatec Hanford Corporation (NHC) to Fluor Federal Services (FFS). For a complete description of the system, including design, please refer to the AZ-101 DAS System Description document, RPP-5572.
Date: February 17, 2000
Creator: BRAYTON, D.D.
Object Type: Report
System: The UNT Digital Library
High-Density Plasma Etching of Group-III Nitride Films for Device Application (open access)

High-Density Plasma Etching of Group-III Nitride Films for Device Application

As III-V nitride device structures become more complicated and design rules shrink, well-controlled etch processes are necessary. Due to limited wet chemical etch results for the group-III nitrides, a significant amount of effort has been devoted to the development of dry etch processing. Dry etch development was initially focused on mesa structures where high etch rates, anisotropic profiles, smooth sidewalls, and equi-rate etching of dissimilar materials were required. For example, commercially available LEDs and laser facets for GaN-based laser diodes have been patterned using reactive ion etching (RIE). With the recent interest in high power, high temperature electronic devices, etch characteristics may also require smooth surface morphology, low plasma-induced damage, and selective etching of one layer over another. The principal criteria for any plasma etch process is its utility in the fabrication of a device. In this study, we will report plasma etch results for the group-III nitrides and their application to device structures.
Date: February 17, 1999
Creator: Baca, A. G.; Crawford, M. H.; Han, J.; Lester, L. F.; Pearton, S. J.; Ren, F. et al.
Object Type: Article
System: The UNT Digital Library
Living with genome instability: the adaptation of phytoplasmas todiverse environments of their insect and plant hosts (open access)

Living with genome instability: the adaptation of phytoplasmas todiverse environments of their insect and plant hosts

Phytoplasmas (Candidatus Phytoplasma, Class Mollicutes) cause disease in hundreds of economically important plants, and are obligately transmitted by sap-feeding insects of the order Hemiptera, mainly leafhoppers and psyllids. The 706,569-bp chromosome and four plasmids of aster yellows phytoplasma strain witches broom (AY-WB) were sequenced and compared to the onion yellows phytoplasma strain M (OY-M) genome. The phytoplasmas have small repeat-rich genomes. The repeated DNAs are organized into large clusters, potential mobile units (PMUs), which contain tra5 insertion sequences (ISs), and specialized sigma factors and membrane proteins. So far, PMUs are unique to phytoplasmas. Compared to mycoplasmas, phytoplasmas lack several recombination and DNA modification functions, and therefore phytoplasmas probably use different mechanisms of recombination, likely involving PMUs, for the creation of variability, allowing phytoplasmas to adjust to the diverse environments of plants and insects. The irregular GC skews and presence of ISs and large repeated sequences in the AY-WB and OY-M genomes are indicative of high genomic plasticity. Nevertheless, segments of {approx}250 kb, located between genes lplA and glnQ are syntenic between the two phytoplasmas, contain the majority of the metabolic genes and no ISs. AY-WB is further along in the reductive evolution process than OY-M. The AY-WB genome is {approx}154 …
Date: February 17, 2006
Creator: Bai, Xiaodong; Zhang, Jianhua; Ewing, Adam; Miller, Sally A.; Radek, Agnes; Shevchenko, Dimitriy et al.
Object Type: Article
System: The UNT Digital Library
Am/Cm Canister Temperature Evaluation in Cim5 (open access)

Am/Cm Canister Temperature Evaluation in Cim5

To facilitate the evaluation of alternate canister designs, 2 canisters were outfitted with thermocouples at elevations of 1/2, 3 1/2, and 6 1/2 inches from the canister bottom. The canisters were fabricated from two inch diameter schedule 10 and two inch diameter schedule 40 stainless steel pipe. Each canister was filled with approximately 2 kilograms of 49 wt percent lanthanide (Ln) loaded 25SrABS glass during 5 inch Cylindrical Induction Melter (CIM5) runs for TTR Tasks 3.03 and 4.03. Melter temperature, total mass of glass poured, and the glass pour rates were almost identical in both runs. The schedule 40 canister has a slightly smaller ID compared to the schedule 10 canister and therefore filled to a level of 9.5 inches compared to 8.0 inches for the schedule 40 canister. The schedule 40 canister had an empty mass of 1906 grams compared to 919 grams for the schedule 10 canister. The schedule 10 canister was found to have a higher maximum surface temperature by about 50--100 C (depending on height) during the glass pour compared to the schedule 40 canister. The additional thermal mass of the schedule 40 canister accounts for this difference. Once filled with glass, each of the canisters …
Date: February 17, 2000
Creator: Baich, M. A.
Object Type: Report
System: The UNT Digital Library
Transistor Counting Systems for Scintillation Detectors (open access)

Transistor Counting Systems for Scintillation Detectors

The requirements for multiple-coincidence counting systems with 10{sup -8}- to 10{sup -9}-sec time resolution can be met economically with presently available high-frequency transistors. The design of solid-state coincidence circuits, amplitude discriminators, and decade scalers is considered and their operation discussed. Several systems have been designed utilizing up to 180 channels from scintillation detectors.
Date: February 17, 1960
Creator: Baker, Stanley C.; Jackson, Horace G. & Mack, Dick A.
Object Type: Report
System: The UNT Digital Library
Multi-century Changes to Global Climate and Carbon Cycle: Results from a Coupled Climate and Carbon Cycle Model (open access)

Multi-century Changes to Global Climate and Carbon Cycle: Results from a Coupled Climate and Carbon Cycle Model

In this paper, we use a coupled climate and carbon cycle model to investigate the global climate and carbon cycle changes out to year 2300 that would occur if CO{sub 2} emissions from all the currently estimated fossil fuel resources were released to the atmosphere. By year 2300, the global climate warms by about 8 K and atmospheric CO{sub 2} reaches 1423 ppmv. The warming is higher than anticipated because the sensitivity to radiative forcing increases as the simulation progresses. In our simulation, the rate of emissions peak at over 30 PgC yr{sup -1} early in the 22nd century. Even at year 2300, nearly 50% of cumulative emissions remain in the atmosphere. In our simulations both soils and living biomass are net carbon sinks throughout the simulation. Despite having relatively low climate sensitivity and strong carbon uptake by the land biosphere, our model projections suggest severe long-term consequences for global climate if all the fossil-fuel carbon is ultimately released to the atmosphere.
Date: February 17, 2005
Creator: Bala, G.; Caldeira, K.; Mirin, A.; Wickett, M. & Delire, C.
Object Type: Article
System: The UNT Digital Library
Development of Ag-clad Bi-2223 superconductors for electric power applications. (open access)

Development of Ag-clad Bi-2223 superconductors for electric power applications.

Development of high-temperature superconductor technology will make possible the design and fabrication of smaller, lighter, and more efficient power devices such as motors, generators, transformers, transmission cables, and fault-current limiters. A prototype fault-current limiter, a 200-hp motor, and a 50-m-long transmission cable have already been demonstrated using Ag-clad Bi-2223 superconductor tapes. We have recently enhanced the transport current properties of long lengths of multifilament Ag-clad Bi-2223 tapes through increased packing density of precursor powder, improved mechanical deformation, optimization of conductor design, and adjusted cooling rate. These improved processing parameters had a pronounced effect on the transport critical current of the super-conducting tapes. Our improvements are briefly discussed and their implications are assessed in this paper.
Date: February 17, 1998
Creator: Balachandran, U.; Eror, N. G.; Haldar, P.; Lelovic, M. & Selvamanickam, V.
Object Type: Article
System: The UNT Digital Library
Stabilization and disposal of Argonne-West low-level mixed wastes in ceramicrete waste forms. (open access)

Stabilization and disposal of Argonne-West low-level mixed wastes in ceramicrete waste forms.

The technology of room-temperature-setting phosphate ceramics or Ceramicrete{trademark} technology, developed at Argonne National Laboratory (ANL)-East is being used to treat and dispose of low-level mixed wastes through the Department of Energy complex. During the past year, Ceramicrete{trademark} technology was implemented for field application at ANL-West. Debris wastes were treated and stabilized: (a) Hg-contaminated low-level radioactive crushed light bulbs and (b) low-level radioactive Pb-lined gloves (part of the MWIR {number_sign} AW-W002 waste stream). In addition to hazardous metals, these wastes are contaminated with low-level fission products. Initially, bench-scale waste forms with simulated and actual waste streams were fabricated by acid-base reactions between mixtures of magnesium oxide powders and an acid phosphate solution, and the wastes. Size reduction of Pb-lined plastic glove waste was accomplished by cryofractionation. The Ceramicrete{trademark} process produces dense, hard ceramic waste forms. Toxicity Characteristic Leaching Procedure (TCLP) results showed excellent stabilization of both Hg and Pb in the waste forms. The principal advantage of this technology is that immobilization of contaminants is the result of both chemical stabilization and subsequent microencapsulation of the reaction products. Based on bench-scale studies, Ceramicrete{trademark} technology has been implemented in the fabrication of 5-gal waste forms at ANL-West. Approximately 35 kg of real …
Date: February 17, 1998
Creator: Barber, D. B.; Singh, D.; Strain, R. V.; Tlustochowicz, M. & Wagh, A. S.
Object Type: Article
System: The UNT Digital Library
Nonlinear diffusion and image contour enhancement (open access)

Nonlinear diffusion and image contour enhancement

None
Date: February 17, 2003
Creator: Barenblatt, G.I. & Vazquez, J.L.
Object Type: Article
System: The UNT Digital Library
Results of Self-Absorption Study on the Versapor 3000 Filters for Radioactive Particulate Air Sampling (open access)

Results of Self-Absorption Study on the Versapor 3000 Filters for Radioactive Particulate Air Sampling

Since the mid-1980s, Pacific Northwest National Laboratory (PNNL) has used a value of 0.85 as the correction factor for self absorption of activity for particulate radioactive air samples collected from building exhaust for environmental monitoring. This value accounts for activity that cannot be detected by direct counting of alpha and beta particles. Emissions can be degraded or blocked by filter fibers for particles buried in the filter material or by inactive dust particles collected with the radioactive particles. These filters are used for monitoring air emissions from PNNL stacks for radioactive particles. This paper describes an effort to re-evaluate self-absorption effects in particulate radioactive air sample filters (Versapor® 3000, 47 mm diameter) used at PNNL. There were two methods used to characterize the samples. Sixty samples were selected from the archive for acid digestion to compare the radioactivity measured by direct gas-flow proportional counting of filters to the results obtained after acid digestion of the filter and counting again by gas-flow proportional detection. Thirty different sample filters were selected for visible light microscopy to evaluate filter loading and particulate characteristics. Mass-loading effects were also considered. Filter ratios were calculated by dividing the initial counts by the post-digestion counts with the …
Date: February 17, 2009
Creator: Barnett, J. M.; Cullinan, Valerie I.; Barnett, Debra S.; Trang-Le, Truc LT; Bliss, Mary; Greenwood, Lawrence R. et al.
Object Type: Report
System: The UNT Digital Library
Influence of specimen design on the deformation and failure of zircaloy cladding (open access)

Influence of specimen design on the deformation and failure of zircaloy cladding

Experimental as well as computational analyses have been used to examine the deformation and failure behavior of ring-stretch specimens of Zircaloy-4 cladding tubes. The results show that, at least for plastically anisotropic unirradiated cladding, specimens with a small gauge length l to width w ratio (l/w {approx} 1) exhibit pronounced non-uniform deformation along their length. As a result, specimen necking occurs upon yielding when the specimen is fully plastic. Finite element analysis indicates a minimum l/w of 4 before a significant fraction of the gauge length deforms homogeneously. A brief examination of the contrasting deformation and failure behavior between uniaxial and plane-strain ring tension tests further supports the use of the latter geometry for determining cladding failure ductility data that are relevant to certain reactivity-initiated accident conditions.
Date: February 17, 2000
Creator: Bates, D. W.; Koss, D. A.; Motta, A. T. & S., Majumdar
Object Type: Article
System: The UNT Digital Library
100 Areas weekly report, February 17, 1955 (open access)

100 Areas weekly report, February 17, 1955

None
Date: February 17, 1955
Creator: Bellas, H. W.
Object Type: Report
System: The UNT Digital Library
Improvements to High-Speed Monitoring of Events in Extreme Environments Using Fiber-optic Bragg Sensors (open access)

Improvements to High-Speed Monitoring of Events in Extreme Environments Using Fiber-optic Bragg Sensors

None
Date: February 17, 2012
Creator: Benterou, J J & Udd, E
Object Type: Article
System: The UNT Digital Library
Threshold resummation of soft gluons in hadronic reactions - an introduction. (open access)

Threshold resummation of soft gluons in hadronic reactions - an introduction.

The authors discuss the motivation for resummation of the effects of initial-state soft gluon radiation, to all orders in the strong coupling strength, for processes in which the near-threshold region in the partonic subenergy is important. The author summarizes the method of perturbative resummation and its application to the calculation of the total cross section for top quark production at hadron colliders. Comments are included on the differences between the treatment of subleading logarithmic terms in this method and in other approaches.
Date: February 17, 1998
Creator: Berger, E. L.
Object Type: Article
System: The UNT Digital Library
PROTEIN NUCLEIC ACID INTERACTIONS GRANT # DE-FG02-96ER62166 FINAL REPORT (open access)

PROTEIN NUCLEIC ACID INTERACTIONS GRANT # DE-FG02-96ER62166 FINAL REPORT

The overall goal of this collaborative project is to develop methods for analyzing protein-nucleic acid interactions. Nucleic acid-binding proteins have a central role in all aspects of genetic activity within an organism, such as transcription, replication, and repair. Thus, it is extremely important to examine the nature of complexes that are formed between proteins and nucleic acids, as they form the basis of our understanding of how these processes take place. Over the past decade, the world has witnessed a great expansion in the determination of high-quality structures of nucleic acid-binding proteins. As a result, the number of such structures has seen a constant increase in the Protein Data Bank (PDB) (1) and the Nucleic Acid Database (NDB) (2). These structures, especially those of proteins in complex with DNA, have provided valuable insight into the stereochemical principles of binding, including how particular base sequences are recognized and how the nucleic acid structure is quite often modified on binding. In this project, we designed several approaches to characterize and classify the properties of both protein-DNA and protein-RNA complexes. In work done in the previous grant period, we developed methods to use experimental data to evaluate nucleic acid crystal structures in order …
Date: February 17, 2005
Creator: Berman, Helen M. & Thornton, Janet
Object Type: Report
System: The UNT Digital Library
Optimization of azimuthal uniformity of thermal conductance between AI TMP and Si cooling arms (open access)

Optimization of azimuthal uniformity of thermal conductance between AI TMP and Si cooling arms

None
Date: February 17, 2010
Creator: Bhandarkar, S D; Mapoles, E A; Kroll, J J; Taylor, J S; Haid, B; Sater, J D et al.
Object Type: Article
System: The UNT Digital Library