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Combination of CDF and D0 Measurements of the $W$ Boson Helicity in Top Quark Decays (open access)

Combination of CDF and D0 Measurements of the $W$ Boson Helicity in Top Quark Decays

This report talks about Combination of CDF and D0 Measurements of the $W$ Boson Helicity in Top Quark Decays
Date: April 20, 2012
Creator: Aaltonen, T
System: The UNT Digital Library
Birth Order and Divergent Thinking: A Meta-Analysis (open access)

Birth Order and Divergent Thinking: A Meta-Analysis

This article is a meta-analysis examining the association of birth order and divergent thinking (DT). The main purpose was to examine how ordinal position (only, first, middle, or last-born) is related to creativity. Results showed that first-borns had higher DT scores than later-born children.
Date: April 20, 2021
Creator: Abdulla Alabbasi, Ahmed M.; Tadik, Harun; Acar, Selcuk & Runco, Mark A.
System: The UNT Digital Library
Air to Muscle and Blood/Plasma to Muscle Distribution of Volatile Organic Compounds and Drugs: Linear Free Energy Analyses (open access)

Air to Muscle and Blood/Plasma to Muscle Distribution of Volatile Organic Compounds and Drugs: Linear Free Energy Analyses

Article on air to muscle and blood/plasma to muscle distribution of volatile organic compounds and drugs and linear free energy analyses.
Date: April 20, 2006
Creator: Abraham, M. H. (Michael H.); Ibrahim, Adam & Acree, William E. (William Eugene)
System: The UNT Digital Library
U.S./Russian cooperative efforts to enhance nuclear MPC&A at VNIITF, (Chelyabinsk-70) (open access)

U.S./Russian cooperative efforts to enhance nuclear MPC&A at VNIITF, (Chelyabinsk-70)

The work described here is part of an effort called the Nuclear Materials Protection, Control, and Accounting (MPC&A) Program, a cooperative program between the US Department of Eenrgy (DOE) and Russia's Ministry of Atomic Energy (MinAtom). The objective of the program is to reduce the risk of nuclear proliferation by strengthening MPC&A systems at Russian nuclear Facilities. This paper describes that portion of the MPC&A program that is directed specifically to the needs of the All Russian Scientific Research Institute of Technical Physics (VNIITF), also called Chelyabinsk-70. A major MPC&A milestone was met at VNIITF when the MPC&A improvements were commissioned at the Pulse Research Reactor Facility in May of this year.
Date: April 20, 1999
Creator: Abramson, B.; Apt, K.; Blasy, J.; Bukin, D.; Churikov, Y.; Curtis, D. et al.
System: The UNT Digital Library
Erratum to: More Comprehensive Forensic Genetic Marker Analyses for Accurate Human Remains Identification Using Massively Parallel DNA Sequencing (open access)

Erratum to: More Comprehensive Forensic Genetic Marker Analyses for Accurate Human Remains Identification Using Massively Parallel DNA Sequencing

This article provides erratum for the article "More Comprehensive Forensic Genetic Marker Analyses for Accurate Human Remains Identification Using Massively Parallel DNA Sequencing," which incorrectly deleted an author from the author list.
Date: April 20, 2017
Creator: Ambers, Angie D.; Churchill, Jennifer D.; King, Jonathan L.; Stoljarova, Monika; Gill-King, Harrell; Assidi, Mourad et al.
System: The UNT Digital Library
Value engineering: A new focus for women in engineering (open access)

Value engineering: A new focus for women in engineering

Value Engineering is an organized problem solving technique that utilizes communication and teamwork skills -- skills heralded as strengths for women. Value Engineering offers an excellent career opportunity for women in the engineering profession. It is an expanded career path that is currently being overlooked by women. Value Engineering is supported by SAVE (Society of American Value Engineers) and certification in the process can be achieved in two years. For women in the engineering profession, VE is an ideal place to redirect their existing skills and training. The number of certified women is a minority, creating a wide-open field of opportunity in federal and state agencies as well as private industry. Value Engineering can provide that new avenue for engineering careers -- a new direction where current skills can be applied to a diverse and exciting profession. 1 fig.
Date: April 20, 1990
Creator: Anderson, L.C.
System: The UNT Digital Library
Fabrication and characterization of Ag-clad Bi-2223 tapes. (open access)

Fabrication and characterization of Ag-clad Bi-2223 tapes.

The powder-in-tube (PIT) technique was used to fabricate multifilament (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub y} (Bi-2223) superconducting tapes. Transport current properties of these tapes were enhanced by increasing the packing density of the precursor powder and improving the mechanical deformation condition. A critical current (I{sub c}) of > 35 A in long lengths (> 200 m) tapes has been achieved. In measuring the dependence of critical current density on magnetic field and temperature for the optimally processed tapes, we found a J{sub c} of > 10{sup 4} A/cm{sup 2} at 20 K in magnetic fields up to 3 T and parallel to the c-axis, which is of interest for use in refrigerator-cooled magnets. I{sub c} declined exponentially when an external field was applied perpendicular to the tape surface at 77 K. Mechanical stability was tested for tapes sheathed with pure Ag and Ag-Mg alloy. Tapes made with pure Ag sheathing can withstand a tensile stress of {approx}20 MPa with no detrimental effect on I{sub c} values. Mechanical performance was improved by using Ag-Mg alloy sheathing: values of transport critical current began to decrease at the tensile stress of {approx} 100 MPa. Transport current measurements on tapes wound on a mandrel …
Date: April 20, 1999
Creator: Balachandran, U.
System: The UNT Digital Library
Mixed-conducting oxides for gas separation applications. (open access)

Mixed-conducting oxides for gas separation applications.

Mixed-conducting oxides are attracting increased attention because of their potential uses in high-temperature electrochemical applications such as solid-oxide fuel cells, batteries, sensors, and gas-permeable membranes. We are developing mixed-conducting, dense ceramic membranes to selectively transport oxygen and hydrogen. Ceramic membranes made of Sr-Fe-Co oxide (SFC), which exhibits high combined electronic and oxygen ionic conductivities, can be used to selectively transport oxygen during the partial oxidation of methane to synthesis gas (syngas, a mixture of CO and H{sub 2}). Steady-state oxygen permeability of SrFeCo{sub 0.5}O{sub x} has been measured as a function of oxygen-partial-pressure gradient and temperature. At 900 C, oxygen permeability was {approx}2.5 scc{center_dot}cm{sup {minus}2}-min{sup {minus}1} for a 2.9-mm-thick membrane, and this value increases as membrane thickness decreases. We have fabricated tubular SrFeCo{sub 0.5}O{sub x} membranes and operated them at 900 C for >1000 h during conversion of methane into syngas. Yttria-doped BaCeO{sub 3} (BCY) is a good protonic conductor; however, its lack of electronic conductivity can potentially limit its hydrogen permeability. To enhance the electronic conductivity and thus improve hydrogen permeation, a membrane composite material was developed. Nongalvanic permeation of hydrogen through the composite membrane was characterized as a function of thickness.
Date: April 20, 1999
Creator: Balachandran, U.
System: The UNT Digital Library
Cooperative Effects in the Annelation of Benzene by Multiple Etheno Groups (open access)

Cooperative Effects in the Annelation of Benzene by Multiple Etheno Groups

Article on cooperative effects in the annelation of benzene by multiple etheno groups.
Date: April 20, 2011
Creator: Bao, Xiaoguang; Hrovat, David A. & Borden, Weston T.
System: The UNT Digital Library
On-Chip Real-Time Single-Copy Polymerase Chain Reaction in Picoliter Droplets (open access)

On-Chip Real-Time Single-Copy Polymerase Chain Reaction in Picoliter Droplets

The first lab-on-chip system for picoliter droplet generation and PCR amplification with real-time fluorescence detection has performed PCR in isolated droplets at volumes 10{sup 6} smaller than commercial real-time PCR systems. The system utilized a shearing T-junction in a silicon device to generate a stream of monodisperse picoliter droplets that were isolated from the microfluidic channel walls and each other by the oil phase carrier. An off-chip valving system stopped the droplets on-chip, allowing them to be thermal cycled through the PCR protocol without droplet motion. With this system a 10-pL droplet, encapsulating less than one copy of viral genomic DNA through Poisson statistics, showed real-time PCR amplification curves with a cycle threshold of {approx}18, twenty cycles earlier than commercial instruments. This combination of the established real-time PCR assay with digital microfluidics is ideal for isolating single-copy nucleic acids in a complex environment.
Date: April 20, 2007
Creator: Beer, N. Reginald; Hindson, Benjamin J.; Wheeler, Elizabeth K.; Hall, Sara B.; Rose, Klint A.; Kennedy, Ian M. et al.
System: The UNT Digital Library
Numerical Simulation of a Laboratory-Scale Turbulent SlotFlame (open access)

Numerical Simulation of a Laboratory-Scale Turbulent SlotFlame

We present three-dimensional, time-dependent simulations ofthe flowfield of a laboratory-scale slot burner. The simulations areperformed using an adaptive time-dependent low Mach number combustionalgorithm based on a second-order projection formulation that conservesboth species mass and total enthalpy. The methodology incorporatesdetailed chemical kinetics and a mixture model for differential speciesdiffusion. Methane chemistry and transport are modeled using the DRM-19mechanism along with its associated thermodynamics and transportdatabases. Adaptive mesh refinementdynamically resolves the flame andturbulent structures. Detailedcomparisons with experimental measurementsshow that the computational results provide a good prediction of theflame height, the shape of the time-averaged parabolic flame surfacearea, and the global consumption speed (the volume per second ofreactants consumed divided by the area of the time-averaged flame). Thethickness of the computed flamebrush increases in the streamwisedirection, and the flamesurface density profiles display the same generalshapes as the experiment. The structure of the simulated flame alsomatches the experiment; reaction layers are thin (typically thinner than1 mm) and the wavelengths of large wrinkles are 5--10 mm. Wrinklesamplify to become long fingers of reactants which burn through at a neckregion, forming isolated pockets of reactants. Thus both the simulatedflame and the experiment are in the "corrugated flameletregime."
Date: April 20, 2006
Creator: Bell, John B.; Day, Marcus S.; Grcar, Joseph F.; Lijewski,Michael J.; Driscoll, James F. & Filatyev, Sergei A.
System: The UNT Digital Library
Review of mirror fusion reactor designs (open access)

Review of mirror fusion reactor designs

Three magnetic confinement concepts, based on the mirror principle, are described. These mirror concepts are summarized as follows: (1) fusion-fission hybrid reactor, (2) tandem mirror reactor, and (3) reversed field mirror reactor. (MOW)
Date: April 20, 1977
Creator: Bender, D. J.
System: The UNT Digital Library
Readiness Reviews: Key to Successfully Implementing Enterprise Systems (open access)

Readiness Reviews: Key to Successfully Implementing Enterprise Systems

Sandia has implemented a formal process to verify that new or modified facilities and operations are ready to safely operate. The readiness review process focuses on the status of management systems, personnel, and systems, structures, and components to do work safely. The scope and depth of the review are tailored to match the potential consequences and the likelihood that the consequences could occur. The precepts and methodology of the process are applicable to verifying the readiness of enterprise systems, and should comprise the final element in developing and implementing an enterprise system. This paper describes the readiness review process, the key elements for success, lessons learned from Sandia's readiness assessment process, and outlines how the process can be applied to enterprise systems. Specific topics addressed include selecting the criteria, approach, and lines of inquiry to be used for the review; selecting members for the review team; team leader responsibilities; reporting and closing deficiencies; and, responsibilities of the facility/project owner and management.
Date: April 20, 1999
Creator: Bendure, A. O.
System: The UNT Digital Library
The APS SASE FEL : modeling and code comparison. (open access)

The APS SASE FEL : modeling and code comparison.

A self-amplified spontaneous emission (SASE) free-electron laser (FEL) is under construction at the Advanced Photon Source (APS). Five FEL simulation codes were used in the design phase: GENESIS, GINGER, MEDUSA, RON, and TDA3D. Initial comparisons between each of these independent formulations show good agreement for the parameters of the APS SASE FEL.
Date: April 20, 1999
Creator: Biedron, S. G.
System: The UNT Digital Library
The operation of the BNL/ATF gun-IV photocathode RF gun at the Advanced Photon Source. (open access)

The operation of the BNL/ATF gun-IV photocathode RF gun at the Advanced Photon Source.

At the Advanced Photon Source (APS) at Argonne National Laboratory (ANL), a free-electron laser (FEL) based on the self-amplified spontaneous emission (SASE) process is nearing completion. Recently, an rf photoinjector gun system was made available to the APS by Brookhaven National Laboratory/Accelerator Test Facility (BNL/ATF). It will be used to provide the high-brightness, low-emittance, and low-energy spread electron beam required by the SASE FEL theory. A Nd:Glass laser system, capable of producing a maximum of 500 {micro}J of UV in a 1-10 ps pulse at up to a 10-Hz repetition rate, serves as the photoinjector's drive laser. Here, the design, commissioning, and integration of this gun with the APS is discussed.
Date: April 20, 1999
Creator: Biedron, S. G.
System: The UNT Digital Library
Reactive Transport Modeling of the Yucca Mountain Site, Nevada (open access)

Reactive Transport Modeling of the Yucca Mountain Site, Nevada

The Yucca Mountain site has a dry climate and deep water table, with the repository located in the middle of an unsaturated zone approximately 600 m thick. Radionuclide transport processes from the repository to the water table are sensitive to the unsaturated zone flow field, as well as to sorption, matrix diffusion, radioactive decay, and colloid transport mechanisms. The unsaturated zone flow and transport models are calibrated against both physical and chemical data, including pneumatic pressure, liquid saturation, water potential, temperature, chloride, and calcite. The transport model predictions are further compared with testing specific to unsaturated zone transport: at Alcove 1 in the Exploratory Studies Facility (ESF), at Alcove 8 and Niche 3 of the ESF, and at the Busted Butte site. The models are applied to predict the breakthroughs at the water table for nonsorbing and sorbing radionuclides, with faults shown as the important paths for radionuclide transport. Daughter products of some important radionuclides, such as {sup 239}Pu and {sup 241}Am, have faster transport than the parents and must be considered in the unsaturated zone transport model. Colloid transport is significantly affected by colloid size, but only negligibly affected by lunetic declogging (reverse filtering) mechanisms. Unsaturated zone model uncertainties …
Date: April 20, 2004
Creator: Bodvarsson, G.
System: The UNT Digital Library
Linear and Nonlinear Ultrasonic Properties of Granular Soils (open access)

Linear and Nonlinear Ultrasonic Properties of Granular Soils

The ultrasonic pulse transmission method (100-500 kHz) was adapted to measure compressional (P) and shear (S) wave velocities for synthetic soils fabricated from quartz-clay and quartz-peat mixtures. Velocities were determined as samples were loaded by small (up to 0.1 MPa) uniaxial stress to determine how stress at grain contacts affects ave amplitudes, velocities, and frequency content. Samples were fabricated from quartz sand mixed with either a swelling clay or peat (natural cellulose). P velocities in these dry synthetic soil samples were low, ranging from about 230 to 430 m/s for pure sand, about 91 to 420 m/s for sand-peat mixtures, and about 230 to 470 m/s for dry sand-clay mixtures. S velocities were about half of the P velocity in most cases, about 130 to 250 m/s for pure sand, about 75-220 m/s for sand-peat mixtures, and about 88-220 m/s for dry sand-clay mixtures. These experiments demonstrate that P and S velocities are sensitive to the amount and type of admixed second phase at low concentrations. They found that dramatic increases in all velocities occur with small uniaxial loads, indicating strong nonlinearity of the acoustic properties. Composition and grain packing contribute to the mechanical response at grain contacts and the …
Date: April 20, 2000
Creator: Bonner, B.; Berge, P. A.; Aracne-Ruddle, C. M.; Bertete-Auguirre, H.; Wildenschild, D.; Trombino, C. N. et al.
System: The UNT Digital Library
Comparison of asymmetric with symmetric feed oil injection parameters in a riser reactor. (open access)

Comparison of asymmetric with symmetric feed oil injection parameters in a riser reactor.

A computational fluid dynamic (CFD) computer code was used to determine the effects of product yields of three feed injection parameters in a fluidized catalytic cracking (FCC) riser reactor. This study includes the effects of both symmetrical and non-symmetrical injection parameters. All these parameters have significant effects on the feed oil spray distribution, vaporization rates and the resulting product yields. This study also indicates that optimum parameter ranges exist for the investigated parameters.
Date: April 20, 1999
Creator: Bowman, B. J.; Chang, S. L.; Lottes, S. A. & Zhou, C. Q.
System: The UNT Digital Library
Assessment and Mitigation of Diagnostic-Generated Electromagnetic Interference at the National Ignition Facility (open access)

Assessment and Mitigation of Diagnostic-Generated Electromagnetic Interference at the National Ignition Facility

Electromagnetic interference (EMI) is an ever-present challenge at laser facilities such as the National Ignition Facility (NIF). The major source of EMI at such facilities is laser-target interaction that can generate intense electromagnetic fields within, and outside of, the laser target chamber. In addition, the diagnostics themselves can be a source of EMI, even interfering with themselves. In this paper we describe EMI generated by ARIANE and DIXI, present measurements, and discuss effects of the diagnostic-generated EMI on ARIANE's CCD and on a PMT nearby DIXI. Finally we present some of the efforts we have made to mitigate the effects of diagnostic-generated EMI on NIF diagnostics.
Date: April 20, 2012
Creator: Brown, C. G.; Ayers, M. J.; Felker, B.; Ferguson, W.; Holder, J P; Nagel, S. R. et al.
System: The UNT Digital Library
Battery charging in float vs. cycling environments (open access)

Battery charging in float vs. cycling environments

In lead-acid battery systems, cycling systems are often managed using float management strategies. There are many differences in battery management strategies for a float environment and battery management strategies for a cycling environment. To complicate matters further, in many cycling environments, such as off-grid domestic power systems, there is usually not an available charging source capable of efficiently equalizing a lead-acid battery let alone bring it to a full state of charge. Typically, rules for battery management which have worked quite well in a floating environment have been routinely applied to cycling batteries without full appreciation of what the cycling battery really needs to reach a full state of charge and to maintain a high state of health. For example, charge target voltages for batteries that are regularly deep cycled in off-grid power sources are the same as voltages applied to stand-by systems following a discharge event. In other charging operations equalization charge requirements are frequently ignored or incorrectly applied in cycled systems which frequently leads to premature capacity loss. The cause of this serious problem: the application of float battery management strategies to cycling battery systems. This paper describes the outcomes to be expected when managing cycling batteries with …
Date: April 20, 2000
Creator: COREY,GARTH P.
System: The UNT Digital Library
Computer simulation of FCC riser reactors. (open access)

Computer simulation of FCC riser reactors.

A three-dimensional computational fluid dynamics (CFD) code, ICRKFLO, was developed to simulate the multiphase reacting flow system in a fluid catalytic cracking (FCC) riser reactor. The code solve flow properties based on fundamental conservation laws of mass, momentum, and energy for gas, liquid, and solid phases. Useful phenomenological models were developed to represent the controlling FCC processes, including droplet dispersion and evaporation, particle-solid interactions, and interfacial heat transfer between gas, droplets, and particles. Techniques were also developed to facilitate numerical calculations. These techniques include a hybrid flow-kinetic treatment to include detailed kinetic calculations, a time-integral approach to overcome numerical stiffness problems of chemical reactions, and a sectional coupling and blocked-cell technique for handling complex geometry. The copyrighted ICRKFLO software has been validated with experimental data from pilot- and commercial-scale FCC units. The code can be used to evaluate the impacts of design and operating conditions on the production of gasoline and other oil products.
Date: April 20, 1999
Creator: Chang, S. L.; Golchert, B.; Lottes, S. A.; Petrick, M. & Zhou, C. Q.
System: The UNT Digital Library
A consortium approach to glass furnace modeling. (open access)

A consortium approach to glass furnace modeling.

Using computational fluid dynamics to model a glass furnace is a difficult task for any one glass company, laboratory, or university to accomplish. The task of building a computational model of the furnace requires knowledge and experience in modeling two dissimilar regimes (the combustion space and the liquid glass bath), along with the skill necessary to couple these two regimes. Also, a detailed set of experimental data is needed in order to evaluate the output of the code to ensure that the code is providing proper results. Since all these diverse skills are not present in any one research institution, a consortium was formed between Argonne National Laboratory, Purdue University, Mississippi State University, and five glass companies in order to marshal these skills into one three-year program. The objective of this program is to develop a fully coupled, validated simulation of a glass melting furnace that may be used by industry to optimize the performance of existing furnaces.
Date: April 20, 1999
Creator: Chang, S.-L.; Golchert, B. & Petrick, M.
System: The UNT Digital Library
Electron Impact Excitation Cross Section Measurement for n=3 to n=2 Line Emission in Fe17+ to Fe23+ (open access)

Electron Impact Excitation Cross Section Measurement for n=3 to n=2 Line Emission in Fe17+ to Fe23+

We have measured the electron impact excitation cross sections for the strong iron L-shell 3 {yields} 2 lines of Fe XVIII to Fe XXIV at the EBIT-I electron beam ion trap using a crystal spectrometer and NASA-Goddard Space Flight Centers 6 x 6 pixel array microcalorimeter. The cross sections were determined by direct normalization to the well established cross section of radiative electron capture through a sophisticated model analysis which results in the excitation cross section for the strong Fe L-shell lines at multiple electron energies. This measurement is part of a laboratory X-ray astrophysics program utilizing the Livermore electron beam ion traps EBIT-I and EBIT-II.
Date: April 20, 2006
Creator: Chen, H; Beiersdorfer, P; Brown, G V; Scofield, J; Gu, M F; Kahn, S M et al.
System: The UNT Digital Library
Laser Peening of Alloy 600 to Improve Intergranular Stress Corrosion Cracking Resistance in Power Plants (open access)

Laser Peening of Alloy 600 to Improve Intergranular Stress Corrosion Cracking Resistance in Power Plants

Laser peening is an emerging modern process that impresses a compressive stress into the surface of metals or alloys. This treatment can reduce the rate of intergranular stress corrosion cracking and fatigue cracking in structural metals or Alloy 600 needed for nuclear power plants.
Date: April 20, 2004
Creator: Chen, H; Rankin, J; Hackel, L; Frederick, G; Hickling, J & Findlan, S
System: The UNT Digital Library