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Non-Poisson Dichotomous Noise: Higher-Order Correlation Functions and Aging (open access)

Non-Poisson Dichotomous Noise: Higher-Order Correlation Functions and Aging

This article discusses non-Poisson dichotomous noise and higher-order correlation functions and aging.
Date: October 26, 2004
Creator: Allegrini, Paolo; Grigolini, Paolo; Palatella, Luigi & West, Bruce J.
System: The UNT Digital Library
Reversible Beta-Hydrogen Elimination of Three-Coordinate Iron(II) Alkyl Complexes: Mechanistic and Thermodynamic Studies (open access)

Reversible Beta-Hydrogen Elimination of Three-Coordinate Iron(II) Alkyl Complexes: Mechanistic and Thermodynamic Studies

Article discussing mechanistic and thermodynamic studies and reversible beta-hydrogen elimination of three-coordinate iron(II) alkyl complexes.
Date: October 1, 2004
Creator: Vela, Javier; Vaddadi, Sridhar; Cundari, Thomas R., 1964-; Smith, Jeremy M.; Gregory, Elizabeth A.; Lachicotte, Rene J. et al.
System: The UNT Digital Library
Reactions of TpRu(CO) (NCMe) (Me) (Tp = Hydridotris(pyrazolyl)borate) with Heteroaromatic Substrates: Stoichiometric and Catalytic C-H Activation (open access)

Reactions of TpRu(CO) (NCMe) (Me) (Tp = Hydridotris(pyrazolyl)borate) with Heteroaromatic Substrates: Stoichiometric and Catalytic C-H Activation

Article discussing reactions of TpRu(CO)(NCMe)(Me) (Tp = Hydridotris(pyrazolyl)borate) with heteroaromatic substrates and stoichiometric and catalytic C-H activation.
Date: October 15, 2004
Creator: Pittard, Karl A.; Lee, John P.; Cundari, Thomas R., 1964-; Gunnoe, T. Brent & Petersen, Jeffrey L.
System: The UNT Digital Library
Using GIS technology to identify areas of tuberculosis transmission and incidence (open access)

Using GIS technology to identify areas of tuberculosis transmission and incidence

This article discusses using GIS technology to identify areas of tuberculosis transmission and incidence.
Date: October 13, 2004
Creator: Moonan, Patrick K.; Bayona, Manuel; Quitugua, Teresa N.; Oppong, Joseph R.; Dunbar, Denise; Jost, Kenneth C. et al.
System: The UNT Digital Library
The Transcriptional Regulator AlgR Controls Cyanide Production in Pseudomonas aeruginosa (open access)

The Transcriptional Regulator AlgR Controls Cyanide Production in Pseudomonas aeruginosa

Article on the transcriptional regulator AlgR controlling cyanide production in Pseudomonas aeruginosa.
Date: October 2004
Creator: Carterson, Alexander J.; Morici, Lisa A.; Jackson, Debra W.; Frisk, Anders; Lizewski, Stephen E.; Jupiter, Ryan et al.
System: The UNT Digital Library
Surface Tension Calculation of Mixed Solvents with Respect to Solvent Composition and Temperature by Using Jouyban-Acree Model (open access)

Surface Tension Calculation of Mixed Solvents with Respect to Solvent Composition and Temperature by Using Jouyban-Acree Model

Article on the surface tension calculation of mixed solvents with respect to solvent composition and temperature by using Jouyban-Acree model.
Date: October 1, 2004
Creator: Jouyban, Abolghasem; Fathi-Azarbayjani, Anahita & Acree, William E. (William Eugene)
System: The UNT Digital Library
Mechanism and modeling of the formation of gaseous alkali sulfates (open access)

Mechanism and modeling of the formation of gaseous alkali sulfates

Article on the mechanism and modeling of the formation of gaseous alkali sulfates.
Date: October 13, 2004
Creator: Glarborg, Peter & Marshall, Paul
System: The UNT Digital Library
Correlation and prediction of partition coefficients between the gas phase and water, and the solvents dodecane and undecane (open access)

Correlation and prediction of partition coefficients between the gas phase and water, and the solvents dodecane and undecane

Article on the correlation and prediction of partition coefficients between the gas phase and water, and the solvents dodecane and undecane.
Date: October 29, 2004
Creator: Abraham, M. H. (Michael H.) & Acree, William E. (William Eugene)
System: The UNT Digital Library
Potential and Future Trends on Industrial Radiation Processing Technology Application in Emerging Country - Brazil (open access)

Potential and Future Trends on Industrial Radiation Processing Technology Application in Emerging Country - Brazil

Brazil started the use of radiation technology in the seventies on crosslinking polyethylene for insulation of wire and electronic cables and sterilization of medical care devices. The present status of industrial applications of radiation shows that the use of this technology is increasing according to the economical development and the necessity to become the products manufactured in the local industries competitive in quality and price for internal and external market. The on going development activities in this area are concentrated on polymers processing (materials modification), foodstuff treatment and environmental protection. The development, the promotion and the technical support to consolidate this technology to the local industries is the main attribution of Institute for Energetic and Nuclear Research-IPEN, a governmental Institution.
Date: October 6, 2004
Creator: Sampa, Maria Helena O.; Omi, Nelson M.; Rela, Carolina S. & Tsai, David
System: The UNT Digital Library
Pybus -- A Python Software Bus (open access)

Pybus -- A Python Software Bus

A software bus, just like its hardware equivalent, allows for the discovery, installation, configuration, loading, unloading, and run-time replacement of software components, as well as channeling of inter-component communication. Python, a popular open-source programming language, encourages a modular design on software written in it, but it offers little or no component functionality. However, the language and its interpreter provide sufficient hooks to implement a thin, integral layer of component support. This functionality can be presented to the developer in the form of a module, making it very easy to use. This paper describes a Pythonmodule, PyBus, with which the concept of a ''software bus'' can be realized in Python. It demonstrates, within the context of the ATLAS software framework Athena, how PyBus can be used for the installation and (run-time) configuration of software, not necessarily Python modules, from a Python application in a way that is transparent to the end-user.
Date: October 14, 2004
Creator: Lavrijsen, Wim T.L.P.
System: The UNT Digital Library
CHARACTERISTICS OF NEXT-GENERATION SPENT NUCLEAR FUEL (SNF) TRANSPORT AND STORAGE CASKS (open access)

CHARACTERISTICS OF NEXT-GENERATION SPENT NUCLEAR FUEL (SNF) TRANSPORT AND STORAGE CASKS

The design of spent nuclear fuel (SNF) casks used in the present SNF disposition systems has evolved from early concepts about the nuclear fuel cycle. The reality today is much different from that envisioned by early nuclear scientists. Most SNF is placed in pool storage, awaiting reprocessing (as in Russia) or disposal at a geologic SNF repository (as in the United States). Very little transport of SNF occurs. This paper examines the requirements for SNF casks from today's perspective and attempts to answer this question: What type of SNF cask would be produced if we were to start over and design SNF casks based on today's requirements? The characteristics for a next-generation SNF cask system are examined and are found to be essentially the same in Russia and the United States. It appears that the new depleted uranium dioxide (DUO2)-steel cermet material will enable these requirements to be met. Depleted uranium (DU) is uranium in which a portion of the 235U isotope has been removed during a uranium enrichment process. The DUO2-steel cermet material is described. The United States and Russia are cooperating toward the development of a next-generation, dual-purpose, storage and transport SNF system.
Date: October 3, 2004
Creator: Haire, M. J.; Forsberg, C. W.; Matveev, V. Z. & Shapovalov, V. I.
System: The UNT Digital Library
Cycles in fossil diversity (open access)

Cycles in fossil diversity

It is well-known that the diversity of life appears to fluctuate during the course the Phanerozoic, the eon during which hard shells and skeletons left abundant fossils (0-542 Ma). Using Sepkoski's compendium of the first and last stratigraphic appearances of 36380 marine genera, we report a strong 62 {+-} 3 Myr cycle, which is particularly strong in the shorter-lived genera. The five great extinctions enumerated by Raup and Sepkoski may be an aspect of this cycle. Because of the high statistical significance, we also consider contributing environmental factors and possible causes.
Date: October 20, 2004
Creator: Rohde, Robert A. & Muller, Richard A.
System: The UNT Digital Library
SPIN DEPENDENCE IN ELASTIC SCATTERING IN THE CNI REGION. (open access)

SPIN DEPENDENCE IN ELASTIC SCATTERING IN THE CNI REGION.

The interference of the electromagnetic spin-flip amplitude with a hadronic spin-nonflip amplitude in the elastic scattering of hadrons leads to significant spin dependencies at very low 4-momentum transfer t (0.001 < |t| < 0.01 (GeV/c){sup 2}). This kinematical region is known as the Coulomb Nuclear Interference (CNI) region. First results on spin effects in polarized proton-proton elastic scattering in the CNI region at 100 GeV from the 2004 polarized proton run at RHIC are presented. Preliminary results on A{sub N} in the elastic scattering of polarized protons off a carbon target over a wide energy range from 4 GeV to 100 GeV from AGS and RHIC are presented as well. These results allow us to further investigate the spin dependence in elastic scattering and the mechanisms at work.
Date: October 10, 2004
Creator: BRAVAR, A.; MAKDISI, Y. & AL., ET
System: The UNT Digital Library
Targetry at the LANL 100 MeV Isotope Production Facility: Les-Sons Learned From Facility Commissioning (open access)

Targetry at the LANL 100 MeV Isotope Production Facility: Les-Sons Learned From Facility Commissioning

The new Isotope Production Facility (IPF) at Los Alamos National Laboratory has been commissioned during the spring of 2004. Commissioning activities focused on the establishment of a radionuclide database, the review and approval of two specific target stack designs, and four trial irradiation runs with subsequent chemical processing and data analyses. This paper highlights some aspects of the facility and the targetry of the two approved target stacks used during the commissioning process.
Date: October 5, 2004
Creator: Nortier, F. M.; Fassbender, M. E.; DeJohn, M.; Hamilton, V. T.; Heaton, R. C.; Jamriska, D. J. et al.
System: The UNT Digital Library
Cancer and aging: The importance of telomeres in genome maintenance (open access)

Cancer and aging: The importance of telomeres in genome maintenance

Telomeres are the specialized DNA-protein structures that cap the ends of linear chromosomes, thereby protecting them from degradation and fusion by cellular DNA repair processes. In vertebrate cells, telomeres consist of several kilobase pairs of DNA having the sequence TTAGGG, a few hundred base pairs of single-stranded DNA at the 3' end of the telomeric DNA tract, and a host of proteins that organize the telomeric double and single stranded DNA into a protective structure. Functional telomeres are essential for maintaining the integrity and stability of genomes. When combined with loss of cell cycle checkpoint controls, telomere dysfunction can lead to genomic instability, a common cause and hallmark of cancer. Consequently, normal mammalian cells respond to dysfunctional telomeres by undergoing apoptosis (programmed cell death) or cellular senescence (permanent cell cycle arrest), two cellular tumor suppressor mechanisms. These tumor suppressor mechanisms are potent suppressors of cancer, but recent evidence suggests that they can antagonistically also contribute to aging phenotypes. Here, we review what is known about the structure and function of telomeres in mammalian cells, particularly human cells, and how telomere dysfunction may arise and contribute to cancer and aging phenotypes.
Date: October 1, 2004
Creator: Rodier, Francis; Kim, Sahn-ho; Nijjar, Tarlochan; Yaswen, Paul & Campisi, Judith
System: The UNT Digital Library
Diagnostic Application of Absolute Neutron Activation Analysis in Hematology (open access)

Diagnostic Application of Absolute Neutron Activation Analysis in Hematology

The Absolute Neutron Activation Analysis (ANAA) technique was used to determine element concentrations of Cl and Na in blood of healthy group (male and female blood donators), select from Blood Banks at Sao Paulo city, to provide information which can help in diagnosis of patients. This study permitted to perform a discussion about the advantages and limitations of using this nuclear methodology in hematological examinations.
Date: October 3, 2004
Creator: Zamboni, C. B.; Oliveira, L. C. & Dalaqua, L. Jr.
System: The UNT Digital Library
Recent Developments of the IRIS Project of Interest for Latin America (open access)

Recent Developments of the IRIS Project of Interest for Latin America

The IRIS (International Reactor Innovative and Secure) reactor design is being developed by an international consortium of 21 organizations from ten countries, including three members from Brazil and one from Mexico. This reflects the interest that Latin America has for a project which addresses the energy needs of the region. Presented here are some of the most recent developments in the IRIS project. The project's highest priority is the current pre-application licensing with the US NRC, which has required an investigation of the major accident sequences and a preliminary probabilistic risk assessment (PRA). The results of the accident analyses confirmed the outstanding inherent safety of the IRIS configuration and the PRA analyses indicated a core damage frequency due to internal events of the order of 2E-8. This not only highlights the enhanced safety characteristic of IRIS which should enhance its public acceptance, but it has also prompted IRIS to consider the possibility of being licensed without the need for off-site emergency response planning which would have a very positive economic implication. The modular IRIS, with each module rated at {approx} 335 MWe, is of course an ideal size for developing countries as it allows to easily introduce a moderate amount …
Date: October 3, 2004
Creator: Carelli, M. D. & Petrovic, B.
System: The UNT Digital Library
Applications of the 3-D Deterministic Transport Attila{reg_sign} for Core Safety Analysis (open access)

Applications of the 3-D Deterministic Transport Attila{reg_sign} for Core Safety Analysis

An LDRD (Laboratory Directed Research and Development) project is ongoing at the Idaho National Engineering and Environmental Laboratory (INEEL) for applying the three-dimensional multi-group deterministic neutron transport code (Attila{reg_sign}) to criticality, flux and depletion calculations of the Advanced Test Reactor (ATR). This paper discusses the model development, capabilities of Attila, generation of the cross-section libraries, and comparisons to an ATR MCNP model and future.
Date: October 6, 2004
Creator: Lucas, D.S.; Gougar, D.; Roth, P.A.; Wareing, T.; Failla, G.; McGhee, J. et al.
System: The UNT Digital Library
Smelting Associated with the Advanced Spent Fuel Conditioning Process (open access)

Smelting Associated with the Advanced Spent Fuel Conditioning Process

The smelting process associated with the advanced spent fuel conditioning process (ACP) of Korea Atomic Energy Research Institute was studied by using surrogate materials. Considering the vaporization behaviors of input materials, the operation procedure of smelting was set up as (1) removal of residual salts, (2) melting of metal powder, and (3) removal of dross from a metal ingot. The behaviors of porous MgO crucible during smelting were tested and the chemical stability of MgO in the salt-being atmosphere was confirmed.
Date: October 3, 2004
Creator: Hur, J. M.; Jeong, M. S.; Lee, W. K.; Cho, S. H.; Seo, C. S. & Park, S. W.
System: The UNT Digital Library
Design Optimization of Radionuclide Nano-Scale Batteries (open access)

Design Optimization of Radionuclide Nano-Scale Batteries

Radioisotopes have been used for power sources in heart pacemakers and space applications dating back to the 50's. Two key properties of radioisotope power sources are high energy density and long half-life compared to chemical batteries. The tritium battery used in heart pacemakers exceeds 500 mW-hr, and is being evaluated by the University of Florida for feasibility as a MEMS (MicroElectroMechanical Systems) power source. Conversion of radioisotope sources into electrical power within the constraints of nano-scale dimensions requires cutting-edge technologies and novel approaches. Some advances evolving in the III-V and II-IV semiconductor families have led to a broader consideration of radioisotopes rather free of radiation damage limitations. Their properties can lead to novel battery configurations designed to convert externally located emissions from a highly radioactive environment. This paper presents results for the analytical computational assisted design and modeling of semiconductor prototype nano-scale radioisotope nuclear batteries from MCNP and EGS programs. The analysis evaluated proposed designs and was used to guide the selection of appropriate geometries, material properties, and specific activities to attain power requirements for the MEMS batteries. Plans utilizing high specific activity radioisotopes were assessed in the investigation of designs employing multiple conversion cells and graded junctions with varying …
Date: October 6, 2004
Creator: Schoenfeld, D.W.; Tulenko, J.S.; Wang, J. & Smith, B.
System: The UNT Digital Library
Industrial Effluent Treatment Using Ionizing Radiation Combined to Titanium Dioxide (open access)

Industrial Effluent Treatment Using Ionizing Radiation Combined to Titanium Dioxide

The Advanced Oxidation Process (AOP) with OH radicals are the most efficient to mineralize organic compounds, and there are various methods to generate OH radicals as the use of ozone, hydrogen peroxide and ultra-violet radiation and ionizing radiation. The irradiation of aqueous solutions with high-energy electrons results in the excitation and ionizing of the molecules and rapid (10{sup -14} - 10{sup -9} s) formation of reactive intermediates. These reactive species will react with organic compounds present in industrial effluent inducing their decomposition. Titanium dioxide (TiO{sub 2}) catalyzed photoreaction is used to remove a wide range of pollutants in air and water media, combined to UV/VIS light, FeO{sub 2}, and H{sub 2}O{sub 2}, but as far as known there is no report on the combination with ionizing radiation. In some recent studies, the removal of organic pollutants in industrial effluent, such as Benzene, Toluene, and Xylene from petroleum production using ionizing radiation was investigated. It has been ob served that none of the methods can be used individually in wastewater treatment applications with good economics and high degree of energy efficiency. In the present work, the efficiency of ionizing radiation in presence of TiO{sub 2} to treat industrial effluent was evaluated. …
Date: October 4, 2004
Creator: Duarte, C.L.; Oikawa, H.; Mori, M.N. & Sampa, M.H.O.
System: The UNT Digital Library
Radionuclide Inventory Management at the New 100 MeV Isotope Production Facility at LANL (open access)

Radionuclide Inventory Management at the New 100 MeV Isotope Production Facility at LANL

The Isotope Production Facility (IPF) at Los Alamos is operated on the authorization basis of a radiological facility with an inventory limit of a Category 3 Nuclear Facility. For the commissioning of IPF, a ''dummy'' target stack containing Zn, Nb and Al disks, and a ''prototype'' stack were irradiated with a proton beam. The ''prototype'' stack contained two pressed RbCl disks, encapsulated in stainless steel, and a Ga metal target. Typical ''prototype'' stack beam parameters were 88.9 {micro}A, 101.3 h. Operation procedures require the projection of all generated radionuclide activities. This is mandatory in order to determine both maximum beam current and maximum beam exposure time. The Monte Carlo code MCNPX and the burn-up code CINDER90 were used to determine maximum beam parameters prior to irradiation. After irradiation, activity estimates were calculated assuming actual average beam parameters. They were entered into an online inventory database, and were later, after chemical separation and radioactive assays, replaced by experimental values. A comparison of ''prototype'' stack experimental yield data to Monte Carlo calculation results showed that the computer codes provide realistic, conservative estimates.
Date: October 3, 2004
Creator: Fassbender, M. E.; Phillips, D. R.; Nortier, F. M.; Trellue, H. R.; Hamilton, V. T.; Heaton, R. C. et al.
System: The UNT Digital Library
Answering Key Fuel Cycle Questions (open access)

Answering Key Fuel Cycle Questions

Given the range of fuel cycle goals and criteria, and the wide range of fuel cycle options, how can the set of options eventually be narrowed in a transparent and justifiable fashion? It is impractical to develop all options. We suggest an approach that starts by considering a range of goals for the Advanced Fuel Cycle Initiative (AFCI) and then posits seven questions, such as whether Cs and Sr isotopes should be separated from spent fuel and, if so, what should be done with them. For each question, we consider which of the goals may be relevant to eventually providing answers. The AFCI program has both ''outcome'' and ''process'' goals because it must address both waste already accumulating as well as completing the fuel cycle in connection with advanced nuclear power plant concepts. The outcome objectives are waste geologic repository capacity and cost, energy security and sustainability, proliferation resistance, fuel cycle economics, and safety. The process objectives are rea diness to proceed and adaptability and robustness in the face of uncertainties.
Date: October 3, 2004
Creator: Piet, S. J.; Dixon, B. W.; Bennett, R. G.; Smith, J. D. & Hill, R. N.
System: The UNT Digital Library
3-D Thermal Evaluations for a Fueled Experiment in the Advanced Test Reactor (open access)

3-D Thermal Evaluations for a Fueled Experiment in the Advanced Test Reactor

The DOE Advanced Fuel Cycle Initiative and Generation IV reactor programs are developing new fuel types for use in the current Light Water Reactors and future advanced reactor concepts. The Advanced Gas Reactor program is planning to test fuel to be used in the Next Generation Nuclear Plant (NGNP) nuclear reactor. Preliminary information for assessing performance of the fuel will be obtained from irradiations performed in the Advanced Test Reactor large ''B'' experimental facility. A test configuration has been identified for demonstrating fuel types typical of gas cooled reactors or fast reactors that may play a role in closing the fuel cycle or increasing efficiency via high temperature operation Plans are to have 6 capsules, each containing 12 compacts, for the test configuration. Each capsule will have its own temperature control system. Passing a helium-neon gas through the void regions between the fuel compacts and the graphite carrier and between the graphite carrier and the capsule wall will control temperature. This design with three compacts per axial level was evaluated for thermal performance to ascertain the temperature distributions in the capsule and test specimens with heating rates that encompass the range of initial heat generation rates.
Date: October 6, 2004
Creator: Ambrosek, Richard G.; Chang, Gray S. & Utterbeck, Debby J.
System: The UNT Digital Library