NanoComposite Stainless Steel Powder Technologies (open access)

NanoComposite Stainless Steel Powder Technologies

Oak Ridge National Laboratory has been investigating a new class of Fe-based amorphous material stemming from a DARPA, Defense Advanced Research Projects Agency initiative in structural amorphous metals. Further engineering of the original SAM materials such as chemistry modifications and manufacturing processes, has led to the development of a class of Fe based amorphous materials that upon processing, devitrify into a nearly homogeneous distribution of nano sized complex metal carbides and borides. The powder material is produced through the gas atomization process and subsequently utilized by several methods; laser fusing as a coating to existing components or bulk consolidated into new components through various powder metallurgy techniques (vacuum hot pressing, Dynaforge, and hot isostatic pressing). The unique fine scale distribution of microstructural features yields a material with high hardness and wear resistance compared to material produced through conventional processing techniques such as casting while maintaining adequate fracture toughness. Several compositions have been examined including those specifically designed for high hardness and wear resistance and a composition specifically tailored to devitrify into an austenitic matrix (similar to a stainless steel) which poses improved corrosion behavior.
Date: July 25, 2012
Creator: DeHoff, R. & Glasgow, C. (MesoCoat, Inc.)
Object Type: Report
System: The UNT Digital Library
Carbon-Based Magnets (open access)

Carbon-Based Magnets

Advanced Research Projects Agency-Energy project sheet summarizing general information about the Rare Earth Alternatives in Critical Technologies (REACT) program including critical needs, innovation and advantages, impacts, and contact information. This sheet discusses a new type of magnet for power generators and motors as part of the "Discovery & Design of Novel Permanent Magnets using Non-strategic Elements having Secure Supply Chains" project.
Date: May 25, 2012
Creator: Virginia Commonwealth University
Object Type: Text
System: The UNT Digital Library
Oxy-Combustion Environment Characterization: Fire- and Steam-Side Corrosion in Advanced Combustion (open access)

Oxy-Combustion Environment Characterization: Fire- and Steam-Side Corrosion in Advanced Combustion

Oxy-fuel combustion is burning a fuel in oxygen rather than air. The low nitrogen flue gas that results is relatively easy to capture CO{sub 2} from for reuse or sequestration. Corrosion issues associated with the environment change (replacement of much of the N{sub 2} with CO{sub 2} and higher sulfur levels) from air- to oxy-firing were examined. Alloys studied included model Fe-Cr alloys and commercial ferritic steels, austenitic steels, and nickel base superalloys. The corrosion behavior is described in terms of corrosion rates, scale morphologies, and scale/ash interactions for the different environmental conditions. Additionally, the progress towards laboratory oxidation tests in advanced ultra-supercritical steam is updated.
Date: September 25, 2012
Creator: Holcomb, G. R.; Tylczak, J.; Meier, G. H.; Lutz, B. S.; Yanar, N. M.; Pettit, F. S. et al.
Object Type: Article
System: The UNT Digital Library
Carbon Capture Technology (open access)

Carbon Capture Technology

Advanced Research Projects Agency-Energy project sheet summarizing general information about the 15 projects that are a part of the Innovative Materials and Processes for Advanced Carbon Capture Technologies (IMPACCT) program including project goals, innovation needs, and potential impacts.
Date: May 25, 2012
Creator: United States. Advanced Research Projects Agency-Energy.
Object Type: Text
System: The UNT Digital Library
Study of the e+ e- to Hadrons Via ISR at BaBar (open access)

Study of the e+ e- to Hadrons Via ISR at BaBar

None
Date: September 25, 2012
Creator: Solodov, E. P.
Object Type: Article
System: The UNT Digital Library
Efficient Phase-Change Materials (open access)

Efficient Phase-Change Materials

Advanced Research Projects Agency-Energy project sheet summarizing general information about the High Energy Advanced Thermal Storage (HEATS) program including critical needs, innovation and advantages, impacts, and contact information. This sheet discusses the development of cost-effective thermal energy storage through the use of high-temperature phase-change materials as part of the "Development of a Low-Cost Thermal Energy Storage System Using Phase-Change Materials with Enhanced Radiation Heat Transfer" project.
Date: May 25, 2012
Creator: University of South Florida
Object Type: Text
System: The UNT Digital Library
Zgoubi users guide (open access)

Zgoubi users guide

N/A
Date: October 25, 2012
Creator: F., Meot
Object Type: Report
System: The UNT Digital Library
Manganese-Aluminum-Based Magnets (open access)

Manganese-Aluminum-Based Magnets

Advanced Research Projects Agency-Energy project sheet summarizing general information about the Rare Earth Alternatives in Critical Technologies (REACT) program including critical needs, innovation and advantages, impacts, and contact information. This sheet discusses the development of specialized magnetic alloys as part of the "Nanocrystalline t-MnAI Permanent Magnets" project.
Date: May 25, 2012
Creator: Dartmouth College
Object Type: Text
System: The UNT Digital Library
Estimation of Equivalent Sea Level Cosmic Ray Exposure for Low Background Experiment (open access)

Estimation of Equivalent Sea Level Cosmic Ray Exposure for Low Background Experiment

While scientists at CERN and other particle accelerators around the world explore the boundaries of high energy physics, the Majorana project investigates the other end of the spectrum with its extremely sensitive, low background, low energy detector. The MAJORANA DEMONSTRATOR aims to detect neutrinoless double beta decay (0νββ), a rare theoretical process in which two neutrons decay into two protons and two electrons, without the emission of the two antineutrinos that are a product of a normal double beta decay. This process is only possible if – and therefore a detection would prove — the neutrino is a Majorana particle, meaning that it is its own antiparticle [Aaselth et al. 2004] . The existence of such a decay would also disprove lepton conservation and give information about the neutrino's mass.
Date: August 25, 2012
Creator: Greene, Austen T. & Orrell, John L.
Object Type: Report
System: The UNT Digital Library
Formed Core Sampler Hydraulic Conductivity Testing (open access)

Formed Core Sampler Hydraulic Conductivity Testing

A full-scale formed core sampler was designed and functionally tested for use in the Saltstone Disposal Facility (SDF). Savannah River National Laboratory (SRNL) was requested to compare properties of the formed core samples and core drilled samples taken from adjacent areas in the full-scale sampler. While several physical properties were evaluated, the primary property of interest was hydraulic conductivity. Differences in hydraulic conductivity between the samples from the formed core sampler and those representing the bulk material were noted with respect to the initial handling and storage of the samples. Due to testing conditions, the site port samples were exposed to uncontrolled temperature and humidity conditions prior to testing whereas the formed core samples were kept in sealed containers with minimal exposure to an uncontrolled environment prior to testing. Based on the results of the testing, no significant differences in porosity or density were found between the formed core samples and those representing the bulk material in the test stand.
Date: September 25, 2012
Creator: Miller, D. H. & Reigel, M. M.
Object Type: Report
System: The UNT Digital Library
Cerium-Based Magnets (open access)

Cerium-Based Magnets

Advanced Research Projects Agency-Energy project sheet summarizing general information about the Rare Earth Alternatives in Critical Technologies (REACT) program including critical needs, innovation and advantages, impacts, and contact information. This sheet discusses magnets made of cerium as part of the "Novel High Energy Permanent Magnet Without Critical Elements" project.
Date: May 25, 2012
Creator: Ames Laboratory
Object Type: Text
System: The UNT Digital Library
Polarization Analysis for Seeded FELs in a Crossed-Planar Undulator (open access)

Polarization Analysis for Seeded FELs in a Crossed-Planar Undulator

The crossed-planar undulator is a promising scheme for full polarization control in x-ray FELs. For SASE FELs, it has been shown a maximum degree of circular polarization of about 80% is achievable at fundamental wavelength just before saturation. In this paper, we study the effectiveness of a crossed undulator for a seeded x-ray FEL. The degree of circular polarization for both the fundamental and the harmonic radiation are considered. Simulations with realistic beam distributions show that a degree of circular polarization of over 90% and 80% is obtainable at the fundamental and 2nd harmonic frequencies, respectively.
Date: June 25, 2012
Creator: Geng, Huiping; /SLAC; Ding, Yuantao; /SLAC; Huang, Zhirong; /SLAC et al.
Object Type: Article
System: The UNT Digital Library
Properties and Interactions of Elementary Particles (open access)

Properties and Interactions of Elementary Particles

We summarize the accomplishments over the last renewal period in a broad program of research in experimental and theoretical High Energy Physics, conducted at the University of Michigan, and supported by the U.S. Department of Energy.
Date: August 25, 2012
Creator: Amidei, Dante; Campbell, Myron; Huterer, Dragan; Kane, Gordon; Liu, James; Qian, Jianming et al.
Object Type: Report
System: The UNT Digital Library
Radiocarbon Dating (open access)

Radiocarbon Dating

Abstract: Radiocarbon dating can be used to determine the age of objects that contain components that were once alive. In the case of human remains, a radiocarbon date can distinguish between a crime scene and an archaeological site. Documents, museum artifacts and art objects can be dated to determine if their age is correct for the historical context. A radiocarbon date does not confirm authenticity, but it can help identify a forgery.
Date: May 25, 2012
Creator: Buchholz, Bruce A.
Object Type: Book Chapter
System: The UNT Digital Library
Radiation Field Simulation and Estimation Algorithms for a Mobile Sensor and a Stationary Unknown Source (open access)

Radiation Field Simulation and Estimation Algorithms for a Mobile Sensor and a Stationary Unknown Source

None
Date: July 25, 2012
Creator: Clark, G. A.
Object Type: Report
System: The UNT Digital Library
The Hydrogen Corrosion of Uranium: Identification of Underlying Causes and Proposed Mitigation Strategies (open access)

The Hydrogen Corrosion of Uranium: Identification of Underlying Causes and Proposed Mitigation Strategies

None
Date: October 25, 2012
Creator: Loui, A
Object Type: Report
System: The UNT Digital Library
Explicit Formulas for 2nd-Order Driving Terms Due to Sextupoles and Chromatic Effects of Quadrupoles. (open access)

Explicit Formulas for 2nd-Order Driving Terms Due to Sextupoles and Chromatic Effects of Quadrupoles.

Optimization of nonlinear driving terms have become a useful tool for designing storage rings, especially modern light sources where the strong nonlinearity is dominated by the large chromatic effects of quadrupoles and strong sextupoles for chromaticity control. The Lie algebraic method is well known for computing such driving terms. However, it appears that there was a lack of explicit formulas in the public domain for such computation, resulting in uncertainty and/or inconsistency in widely used codes. This note presents explicit formulas for driving terms due to sextupoles and chromatic effects of quadrupoles, which can be considered as thin elements. The computation is accurate to the 4th-order Hamiltonian and 2nd-order in terms of magnet parameters. The results given here are the same as the APS internal note AOP-TN-2009-020. This internal nte has been revised and published here as a Light Source Note in order to get this information into the public domain, since both ELEGANT and OPA are using these formulas.
Date: April 25, 2012
Creator: Wang, C-X. (Accelerator Systems Division (APS))
Object Type: Report
System: The UNT Digital Library
Evaluation of Cavity Collapse and Surface Crater Formation at the Salut Underground Nuclear Test in U20ak, Nevada National Security Site, and the Impact of Stability of the Ground Surface (open access)

Evaluation of Cavity Collapse and Surface Crater Formation at the Salut Underground Nuclear Test in U20ak, Nevada National Security Site, and the Impact of Stability of the Ground Surface

At the request of Jerry Sweeney, the LLNL Containment Program performed a review of nuclear test-related data for the Salut underground nuclear test in U20ak to assist in evaluating this legacy site as a test bed for application technologies for use in On-Site Inspections (OSI) under the Comprehensive Nuclear Test Ban Treaty. Review of the Salut site is complicated because the test experienced a subsurface, rather than surface, collapse. Of particular interest is the stability of the ground surface above the Salut detonation point. Proposed methods for on-site verification include radiological signatures, artifacts from nuclear testing activities, and imaging to identify alteration to the subsurface hydrogeologogy due to the nuclear detonation. Sweeney's proposal requires physical access at or near the ground surface of specific underground nuclear test locations at the Nevada Nuclear Test Site (NNSS, formerly the Nevada Test Site), and focuses on possible activities such as visual observation, multispectral measurements, and shallow, and deep geophysical surveys.
Date: April 25, 2012
Creator: Pawloski, G. A.
Object Type: Report
System: The UNT Digital Library
Final Report DOE Award # DE-FG02-05ER46218, Texas Tech University: "Cyclic Macromolecules: Dynamics and Nonlinear Rheology" (open access)

Final Report DOE Award # DE-FG02-05ER46218, Texas Tech University: "Cyclic Macromolecules: Dynamics and Nonlinear Rheology"

The work described in the present report had the original goal to produce large, entangled, ring polymers that were uncontaminated by linear chains and to characterize by rheological methods the dynamics of these rings. While the work fell short of this specific goal, the outcomes of the research performed under support from this grant provided novel macromolecular synthesis methods, new separation methods for ring and linear chains, and novel rheological data on bottle brush polymers, wedge polymers and dendron-based ring molecules. The grant funded a total of 8 archival manuscripts and one patent, all of which are attached to the present report.
Date: April 25, 2012
Creator: McKenna, Gregory B.; Grubbs, Robert H. & Kornfield, Julia A.
Object Type: Report
System: The UNT Digital Library
Synergistic Effects of Turbine Wakes and Atmospheric Stability on Power Production at an Onshore Wind Farm (open access)

Synergistic Effects of Turbine Wakes and Atmospheric Stability on Power Production at an Onshore Wind Farm

This report examines the complex interactions between atmospheric stability and turbine-induced wakes on downwind turbine wind speed and power production at a West Coast North American multi-MW wind farm. Wakes are generated when the upwind flow field is distorted by the mechanical movement of the wind turbine blades. This has two consequences for downwind turbines: (1) the downwind turbine encounters wind flows with reduced velocity and (2) the downwind turbine encounters increased turbulence across multiple length scales via mechanical turbulence production by the upwind turbine. This increase in turbulence on top of ambient levels may increase aerodynamic fatigue loads on the blades and reduce the lifetime of turbine component parts. Furthermore, ambient atmospheric conditions, including atmospheric stability, i.e., thermal stratification in the lower boundary layer, play an important role in wake dissipation. Higher levels of ambient turbulence (i.e., a convective or unstable boundary layer) lead to higher turbulent mixing in the wake and a faster recovery in the velocity flow field downwind of a turbine. Lower levels of ambient turbulence, as in a stable boundary layer, will lead to more persistent wakes. The wake of a wind turbine can be divided into two regions: the near wake and far wake, …
Date: January 25, 2012
Creator: Wharton, S; Lundquist, J K & Marjanovic, N
Object Type: Report
System: The UNT Digital Library
Wavelength Shifting Phoswich Detectors for Superior Depth-of-Interaction Resolution (open access)

Wavelength Shifting Phoswich Detectors for Superior Depth-of-Interaction Resolution

In order to simultaneously achieve both high spatial resolution and high sensitivity in small Positron Emission Tomography (PET) systems, scintillation detectors must be long in the radial direction as well as able to provide depth-of-interaction (DOI) information. DOI information is typically provided by constructing detectors from two or more layers of scintillators that are identifiable due to their different decay times. This approach has worked well in tomographs such as the High Resolution Research Tomograph (HRRT, CTI PET Systems, Inc.) in which the emission and excitation bands of the scintillator layers do not overlap each other. However, many potentially important pairs of scintillator crystals exist in which the emission of one crystal is, in fact, absorbed and re-emitted by the second crystal, thus impacting the pulse shape discrimination process used to identify the scintillator layers. These potentially useful pairs of scintillators are unlikely to be implemented in phoswich detectors without a comprehensive understanding of the complex emission that results when the light of one crystal is absorbed by the second crystal and then reemitted. Our objective is to develop a fundamental understanding of the optical phenomena that occur in phoswich detectors and to exploit these phenomena to achieve improved spatial …
Date: October 25, 2012
Creator: Melcher, Charles L & Eriksson, Lars
Object Type: Report
System: The UNT Digital Library
Lawrence Livermore National Laboratory Environmental Report 2011 (open access)

Lawrence Livermore National Laboratory Environmental Report 2011

None
Date: September 25, 2012
Creator: Jones, H E; Bake, R G; Bertoldo, N A; Cerruti, S J; Dibley, V R; Doman, J L et al.
Object Type: Report
System: The UNT Digital Library
Calculation of Eddy Currents In the CTH Vacuum Vessel and Coil Frame (open access)

Calculation of Eddy Currents In the CTH Vacuum Vessel and Coil Frame

Knowledge of eddy currents in the vacuum vessel walls and nearby conducting support structures can significantly contribute to the accuracy of Magnetohydrodynamics (MHD) equilibrium reconstruction in toroidal plasmas. Moreover, the magnetic fields produced by the eddy currents could generate error fields that may give rise to islands at rational surfaces or cause field lines to become chaotic. In the Compact Toroidal Hybrid (CTH) device (R0 = 0.75 m, a = 0.29 m, B ≤ 0.7 T), the primary driver of the eddy currents during the plasma discharge is the changing flux of the ohmic heating transformer. Electromagnetic simulations are used to calculate eddy current paths and profile in the vacuum vessel and in the coil frame pieces with known time dependent currents in the ohmic heating coils. MAXWELL and SPARK codes were used for the Electromagnetic modeling and simulation. MAXWELL code was used for detailed 3D finite-element analysis of the eddy currents in the structures. SPARK code was used to calculate the eddy currents in the structures as modeled with shell/surface elements, with each element representing a current loop. In both cases current filaments representing the eddy currents were prepared for input into VMEC code for MHD equilibrium reconstruction of …
Date: September 25, 2012
Creator: Zolfaghari, A.; Brooks, A; Michaels, A.; Hanson, J. & Hartwell, G.
Object Type: Article
System: The UNT Digital Library
Recent Bottomonium Results from BaBar and Belle (open access)

Recent Bottomonium Results from BaBar and Belle

Selected studies in bottomonium physics carried out by the BaBar and Belle experiments are presented. They include a study of radiative bottomonium transitions using {gamma} {yields} e{sup +}e{sup -} conversions done by BaBar, the search for the h{sub b}(1P) and h{sub b}(2P) states leading to an evidence for the h{sub b}(1P) seen by BaBar in {Upsilon}(3S) {yields} {pi}{sup 0} h{sub b} decay and to the Belle observation of both the h{sub b}(1P) and the h{sub b}(2P) in the reaction e{sup +}e{sup -} {yields} {pi}{sup +}{pi}{sup -} h{sub b}(1P,2P) from {Upsilon}(5S) data.
Date: June 25, 2012
Creator: Ziegler, Veronique
Object Type: Article
System: The UNT Digital Library