METAL MEDIA FILTERS, AG-1 SECTION FI (open access)

METAL MEDIA FILTERS, AG-1 SECTION FI

One application of metal media filters is in various nuclear air cleaning processes including applications for protecting workers, the public and the environment from hazardous and radioactive particles. To support this application the development of the ASME AG-1 FI Standard on Metal Media has been under way for more than ten years. Development of the proposed section has required resolving several difficult issues associated with operating conditions (media velocity, pressure drop, etc.), qualification testing, and quality acceptance testing. Performance characteristics of metal media are dramatically different than the glass fiber media with respect to parameters like differential pressures, operating temperatures, media strength, etc. These differences make existing data for a glass fiber media inadequate for qualifying a metal media filter for AG-1. In the past much work has been conducted on metal media filters at facilities such as Lawrence Livermore National Laboratory (LLNL) and Savannah River National Laboratory (SRNL) to qualify the media as High Efficiency Particulate Air (HEPA) Filters. Particle retention testing has been conducted at Oak Ridge Filter Test Facility and at Air Techniques International (ATI) to prove that the metal media meets or exceeds the 99.97% particle retention required for a HEPA Filter. Even with his testing, …
Date: May 23, 2012
Creator: Adamson, D.
Object Type: Article
System: The UNT Digital Library
2010 MICROBIAL STRESS RESPONSE GORDON RESEARCH CONFERENCE, JULY 18-23, 2010 (open access)

2010 MICROBIAL STRESS RESPONSE GORDON RESEARCH CONFERENCE, JULY 18-23, 2010

The 2010 Gordon Research Conference on Microbial Stress Responses provides an open and exciting forum for the exchange of scientific discoveries on the remarkable mechanisms used by microbes to survive in nearly every niche on the planet. Understanding these stress responses is critical for our ability to control microbial survival, whether in the context of biotechnology, ecology, or pathogenesis. From its inception in 1994, this conference has traditionally employed a very broad definition of stress in microbial systems. Sessions will cover the major steps of stress responses from signal sensing to transcriptional regulation to the effectors that mediate responses. A wide range of stresses will be represented. Some examples include (but are not limited to) oxidative stress, protein quality control, antibiotic-induced stress and survival, envelope stress, DNA damage, and nutritional stress. The 2010 meeting will also focus on the role of stress responses in microbial communities, applied and environmental microbiology, and microbial development. This conference brings together researchers from both the biological and physical sciences investigating stress responses in medically- and environmentally relevant microbes, as well as model organisms, using cutting-edge techniques. Computational, systems-level, and biophysical approaches to exploring stress responsive circuits will be integrated throughout the sessions alongside the …
Date: July 23, 2011
Creator: Ades, Sarah
Object Type: Article
System: The UNT Digital Library
Gravitomagnetism in Quantum Mechanics (open access)

Gravitomagnetism in Quantum Mechanics

None
Date: November 23, 2011
Creator: Adler, Ronald J.; /Stanford U., HEPL; Chen, Pisin & /Taiwan, Natl. Taiwan U. /KIPAC, Menlo Park
Object Type: Article
System: The UNT Digital Library
EVALUATION OF POTENTIAL ELUANTS FOR NON-ACID ELUTION OF CESIUM FROM SPHERICAL RESORCINOL-FORMALDEHYDE RESIN (open access)

EVALUATION OF POTENTIAL ELUANTS FOR NON-ACID ELUTION OF CESIUM FROM SPHERICAL RESORCINOL-FORMALDEHYDE RESIN

Ion Exchange column loading and elution of cesium from spherical resorcinol-formaldehyde resin have been conducted for two potential non-acid eluants -(NH{sub 4}){sub 2}CO{sub 3} and CH{sub 3}COONH{sub 4}. The results revealed encouraging cesium elution performance. 100% elution was achieved in at most 22 hours ({approx}28 bed volumes) of elution. Elution performance was fairly high at 6 hours ({approx}8 bed volumes) of elution for some of the eluants and also practically comparable to the benchmark acid eluant (HNO{sub 3}). Hence, it is quite possible 100% percent elution will be closer to the 6th hour than the 22nd hour. Elution is generally enhanced by increasing the concentration and pH of the eluants, and combining the eluants.
Date: October 23, 2011
Creator: Adu-Wusu, K.; Nash, C. & Pennebaker, F.
Object Type: Article
System: The UNT Digital Library
Linear and chromatic optics measurements at RHIC (open access)

Linear and chromatic optics measurements at RHIC

Measurements of chromatic beta-beating were carried out for the first time in the RHIC accelerator during Run 2009. The analysis package developed for the LHC was used to extract the off-momentum optics for injection and top energy. Results from the beam experiments and compassion to the optics model are presented. The primary goal of the RHIC experiments were execute an on-line measurement of the optics using the tools developed for the LHC. Turn-by-turn BPM trajectories (typically 1000 turns) acquired immediately after an external dipole kick are numerically analyzed to determine the optical parameters at the location of the beam position monitors (BPMs). For chromatic optics, a similar analysis, but on a beam with finite momentum offset(s). Each optical measurement typically is calculated from multiple data sets to capture statistical variations and ensure reproducibility. The procedure of measurement and analysis is detailed in ref [1, 2]. Two dedicated experiments were performed at RHIC with protons during Run 2009. The first at injection energy and optics and the other at 250 GeV and squeezed optics. The basic RHIC parameters relevant for the two experiments are listed in Table 1.
Date: May 23, 2010
Creator: Aiba, M.; Calaga, R.; Aiba, M.; Tomas, R. & Vanbavinkove, G.
Object Type: Article
System: The UNT Digital Library
Offshore Wind Turbines - Estimated Noise from Offshore Wind Turbine, Monhegan Island, Maine: Environmental Effects of Offshore Wind Energy Development (open access)

Offshore Wind Turbines - Estimated Noise from Offshore Wind Turbine, Monhegan Island, Maine: Environmental Effects of Offshore Wind Energy Development

Deep C Wind, a consortium headed by the University of Maine will test the first U.S. offshore wind platforms in 2012. In advance of final siting and permitting of the test turbines off Monhegan Island, residents of the island off Maine require reassurance that the noise levels from the test turbines will not disturb them. Pacific Northwest National Laboratory, at the request of the University of Maine, and with the support of the U.S. Department of Energy Wind Program, modeled the acoustic output of the planned test turbines.
Date: November 23, 2010
Creator: Aker, Pamela M.; Jones, Anthony M. & Copping, Andrea E.
Object Type: Report
System: The UNT Digital Library
Electron Cloud at Low Emittance in CesrTA (open access)

Electron Cloud at Low Emittance in CesrTA

The Cornell Electron Storage Ring (CESR) has been reconfigured as a test accelerator (CesrTA) for a program of electron cloud (EC) research at ultra low emittance. The instrumentation in the ring has been upgraded with local diagnostics for measurement of cloud density and with improved beam diagnostics for the characterization of both the low emittance performance and the beam dynamics of high intensity bunch trains interacting with the cloud. A range of EC mitigation methods have been deployed and tested and their effectiveness is discussed. Measurements of the electron cloud's effect on the beam under a range of conditions are discussed along with the simulations being used to quantitatively understand these results.
Date: May 23, 2010
Creator: Alexander, J. P.; Billing, M. G.; Calvey, J.; Crittenden, J. A.; Dugan, G.; Eggert, N. et al.
Object Type: Article
System: The UNT Digital Library
Method Evaluation And Field Sample Measurements For The Rate Of Movement Of The Oxidation Front In Saltstone (open access)

Method Evaluation And Field Sample Measurements For The Rate Of Movement Of The Oxidation Front In Saltstone

The objective of this work was to develop and evaluate a series of methods and validate their capability to measure differences in oxidized versus reduced saltstone. Validated methods were then applied to samples cured under field conditions to simulate Performance Assessment (PA) needs for the Saltstone Disposal Facility (SDF). Four analytical approaches were evaluated using laboratory-cured saltstone samples. These methods were X-ray absorption spectroscopy (XAS), diffuse reflectance spectroscopy (DRS), chemical redox indicators, and thin-section leaching methods. XAS and thin-section leaching methods were validated as viable methods for studying oxidation movement in saltstone. Each method used samples that were spiked with chromium (Cr) as a tracer for oxidation of the saltstone. The two methods were subsequently applied to field-cured samples containing chromium to characterize the oxidation state of chromium as a function of distance from the exposed air/cementitious material surface.
Date: August 23, 2012
Creator: Almond, P. M.; Kaplan, D. I.; Langton, C. A.; Stefanko, D. B.; Spencer, W. A.; Hatfield, A. et al.
Object Type: Report
System: The UNT Digital Library
Analysis of 2010 Meteorological Data from the Knolls Atomic Power Laboratory and Kesselring Site Operations Facilities (open access)

Analysis of 2010 Meteorological Data from the Knolls Atomic Power Laboratory and Kesselring Site Operations Facilities

None
Date: August 23, 2011
Creator: Aluzzi, F J
Object Type: Report
System: The UNT Digital Library
Ultra-high efficiency multilayer blazed gratings through deposition kinetic control (open access)

Ultra-high efficiency multilayer blazed gratings through deposition kinetic control

Diffraction efficiency of multilayer coated blazed gratings (MBG) strongly depends on the perfection of the saw-toothshaped layers in the overall composite structure. Growth of multilayers on saw-tooth substrates should be carefully optimized in order to reduce groove profile distortion and at the same time to avoid significant roughening of multilayer interfaces. In this work we report on a new way to optimize growth of sputter-deposited Mo/Si multilayers on saw-tooth substrates through variation of the sputtering gas pressure. A new record for diffraction efficiency of 44% was achieved for a optimized MBG with groove density of 5250 lines/mm at the wavelength of 13.1 nm.
Date: January 23, 2012
Creator: Anderson, Erik; Gullikson, Eric; Salmassi, Farhad; Warwick, Tony; Yashchuk, Valeriy & Padmore, Howard
Object Type: Article
System: The UNT Digital Library
Atomic-level cotrol of the thermoelectric properties in polytypoid nanowires (open access)

Atomic-level cotrol of the thermoelectric properties in polytypoid nanowires

Thermoelectric materials have generated interest as a means of increasing the efficiency of power generation through the scavenging of waste heat. Materials containing nanometer-sized structural and compositional features can exhibit enhanced thermoelectric performance due to the decoupling of certain electrical and thermal properties, but the extent to which these features can be controlled is often limited. Here we report a simple synthesis of M{sub 2}O{sub 3}(ZnO){sub n} (M = In, Ga, Fe) nanowires with controllable polytypoid structures, where the nanostructured features are tuned by adjusting the amount of metal precursor. After the introduction of nanometer-scale features (individual atomic layers and alloying), thermal and electrical measurements on single In{sub 2-x}Ga{sub x}O3(ZnO){sub n} nanowires reveal a simultaneous improvement in all contributing factors to the thermoelectric figure of merit, indicating successful modification of the nanowire transport properties.
Date: October 23, 2010
Creator: Andrews, Sean C.; Fardy, Melissa A.; Moore, Michael C.; Aloni, Shaoul; Zhang, Minjuan; Radmilovic, Velimir et al.
Object Type: Article
System: The UNT Digital Library
Observation of off-Hugoniot shocked states with ultrafast time resolution (open access)

Observation of off-Hugoniot shocked states with ultrafast time resolution

We apply ultrafast single shot interferometry to determine the pressure and density of argon shocked from up to 7.8 GPa static initial pressure in a diamond anvil cell. This method enables the observation of thermodynamic states distinct from those observed in either single shock or isothermal compression experiments, and the observation of ultrafast dynamics in shocked materials. We also present a straightforward method for interpreting ultrafast shock wave data which determines the index of refraction at the shock front, and the particle and shock velocities for shock waves in transparent materials. Based on these methods, we observe shocked thermodynamic states between the room temperature isotherm of argon and the shock adiabat of cryogenic argon at final shock pressures up to 28 GPa.
Date: February 23, 2010
Creator: Armstrong, M; Crowhurst, J; Bastea, S & Zaug, J
Object Type: Article
System: The UNT Digital Library
TUNING SILICON NANORODS FOR ANODES OF LI-ION RECHARGEABLE BATTERIES (open access)

TUNING SILICON NANORODS FOR ANODES OF LI-ION RECHARGEABLE BATTERIES

Silicon is a promising anode material for Li-ion batteries in regarding of high capacity, low cost and safety, but it suffers poor cycling stability due to the pulverization induced by severe volume expansion/shrinkage (297%) during lithium insertion/extraction. In our previous investigation on aluminum nanorods anodes, it is found the selection of substrates in which Al nanorods grown plays the role in prevention of pulverization resulting in the increase of cycling life. Adapting this knowledge, we investigated the Si based nanorods anodes by tuning its composition and element distribution. Our results show that although the Si nanorods demonstrated higher initial anodic capacity of 1500 mAh/g, it diminished after 50 cycles due to morphology change and pulverization. By codepositing Cu, the Si-Cu composite nanorods demonstrated sustainable capacity of 500 mAh/g in 100 cycles attributing to its flexible and less brittle nature.
Date: November 23, 2010
Creator: Au, M.
Object Type: Article
System: The UNT Digital Library
Beam Polarization at the ILC: the Physics Impact and the Accelerator Solutions (open access)

Beam Polarization at the ILC: the Physics Impact and the Accelerator Solutions

In this contribution accelerator solutions for polarized beams and their impact on physics measurements are discussed. Focus are physics requirements for precision polarimetry near the interaction point and their realization with polarized sources. Based on the ILC baseline programme as described in the Reference Design Report (RDR), recent developments are discussed and evaluated taking into account physics runs at beam energies between 100 GeV and 250 GeV, as well as calibration runs on the Z-pole and options as the 1TeV upgrade and GigaZ. The studies, talks and discussions presented at this conference demonstrated that beam polarization and its measurement are crucial for the physics success of any future linear collider. To achieve the required precision it is absolutely decisive to employ multiple devices for testing and controlling the systematic uncertainties of each polarimeter. The polarimetry methods for the ILC are complementary: with the upstream polarimeter the measurements are performed in a clean environment, they are fast and allow to monitor time-dependent variations of polarization. The polarimeter downstream the IP will measure the disrupted beam resulting in high background and much lower statistics, but it allows access to the depolarization at the IP. Cross checks between the polarimeter results give redundancy …
Date: November 23, 2011
Creator: Aurand, B.; Bailey, I.; Bartels, C.; Brachmann, A.; Clarke, J.; Hartin, A. et al.
Object Type: Article
System: The UNT Digital Library
Design of Survey X-Ray Spectrometer for NIF, NSS (open access)

Design of Survey X-Ray Spectrometer for NIF, NSS

None
Date: August 23, 2013
Creator: Ayers, Shannon; Bell, Perry; Bradley, Dave; Feldman, Uri; Marlin, Walter; Schneider, Marilyn et al.
Object Type: Article
System: The UNT Digital Library
Novel Geometries for the LHC Crab Cavity (open access)

Novel Geometries for the LHC Crab Cavity

The planned luminosity upgrade to LHC is likely to necessitate a large crossing angle and a local crab crossing scheme. For this scheme crab cavities align bunches prior to collision. The scheme requires at least four such cavities, a pair on each beam line either side of the interaction point (IP). Upstream cavities initiate rotation and downstream cavities cancel rotation. Cancellation is usually done at a location where the optics has re-aligned the bunch. The beam line separation near the IP necessitates a more compact design than is possible with elliptical cavities such as those used at KEK. The reduction in size must be achieved without an increase in the operational frequency to maintain compatibility with the long bunch length of the LHC. This paper proposes a suitable superconducting variant of a four rod coaxial deflecting cavity (to be phased as a crab cavity), and presents analytical models and simulations of suitable designs.
Date: May 23, 2010
Creator: B. Hall, G. Burt, C. Lingwood, R. Rimmer, H. Wang
Object Type: Article
System: The UNT Digital Library
A new first-principles calculation of field-dependent RF surface impedance of BCS superconductor (open access)

A new first-principles calculation of field-dependent RF surface impedance of BCS superconductor

N/A
Date: September 23, 2013
Creator: B., Xiao & Reece, C.
Object Type: Article
System: The UNT Digital Library
International Linear Collider Technical Design Report - Volume 2: Physics (open access)

International Linear Collider Technical Design Report - Volume 2: Physics

None
Date: September 23, 2013
Creator: Baer, Howard; Barklow, Tim; Fujii, Keisuke; Gao, Yuanning; Hoang, Andre; Kanemura, Shinya et al.
Object Type: Report
System: The UNT Digital Library
RHIC Spin Flipper Commissioning Status (open access)

RHIC Spin Flipper Commissioning Status

The commissioning of the RHIC spin flipper in the RHIC Blue ring during the RHIC polarized proton run in 2009 showed the detrimental effects of global vertical coherent betatron oscillation induced by the 2-AC dipole plus 4-DC dipole configuration. This global orbital coherent oscillation of the RHIC beam in the Blue ring in the presence of collision modulated the beam-beam interaction between the two RHIC beams and affected Yellow beam polarization. The experimental data at injection with different spin tunes by changing the snake current also demonstrated that it was not possible to induce a single isolated spin resonance with the global vertical coherent betatron oscillation excited by the two AC dipoles. Hence, a new design was proposed to eliminate the coherent vertical betatron oscillation outside the spin flipper by adding three additional AC dipoles. This paper presents the experimental results as well as the new design.
Date: May 23, 2010
Creator: Bai, M.; Meot, F.; Dawson, C.; Oddo, P.; Pai, C.; Pile, P. et al.
Object Type: Article
System: The UNT Digital Library
Radiative B Decays (open access)

Radiative B Decays

I discuss recent results in radiative B decays from the Belle and BaBar collaborations. I report new measurements of the decay rate and CP asymmetries in b {yields} s{gamma} and b {yields} d{gamma} decays, and measurements of the photon spectrum in b {yields} s{gamma}. Radiative penguin decays are flavour changing neutral currents which do not occur at tree level in the standard model (SM), but must proceed via one loop or higher order diagrams. These transitions are therefore suppressed in the SM, but offer access to poorlyknown SM parameters and are also a sensitive probe of new physics. In the SM, the rate is dominated by the top quark contribution to the loop, but non-SM particles could also contribute with a size comparable to leading SM contributions. The new physics effects are potentially large which makes them theoretically very interesting, but due to their small branching fractions they are typically experimentally challenging.
Date: November 23, 2011
Creator: Bard, D.
Object Type: Article
System: The UNT Digital Library
Development of MMC Gamma Detectors for Nuclear Analysis (open access)

Development of MMC Gamma Detectors for Nuclear Analysis

None
Date: January 23, 2014
Creator: Bates, C. R.; Pies, C.; Kempf, S.; Gastaldo, L.; Fleischmann, A.; Enss, C. et al.
Object Type: Article
System: The UNT Digital Library
2009 ALCF annual report. (open access)

2009 ALCF annual report.

This year the Argonne Leadership Computing Facility (ALCF) delivered nearly 900 million core hours of science. The research conducted at their leadership class facility touched our lives in both minute and massive ways - whether it was studying the catalytic properties of gold nanoparticles, predicting protein structures, or unearthing the secrets of exploding stars. The authors remained true to their vision to act as the forefront computational center in extending science frontiers by solving pressing problems for our nation. Our success in this endeavor was due mainly to the Department of Energy's (DOE) INCITE (Innovative and Novel Computational Impact on Theory and Experiment) program. The program awards significant amounts of computing time to computationally intensive, unclassified research projects that can make high-impact scientific advances. This year, DOE allocated 400 million hours of time to 28 research projects at the ALCF. Scientists from around the world conducted the research, representing such esteemed institutions as the Princeton Plasma Physics Laboratory, National Institute of Standards and Technology, and European Center for Research and Advanced Training in Scientific Computation. Argonne also provided Director's Discretionary allocations for research challenges, addressing such issues as reducing aerodynamic noise, critical for next-generation 'green' energy systems. Intrepid - the …
Date: November 23, 2010
Creator: Beckman, P.; Martin, D. & Drugan, C.
Object Type: Report
System: The UNT Digital Library
Beam break-up estimates for the ERL at BNL (open access)

Beam break-up estimates for the ERL at BNL

A prototype Ampere-class superconducting energy recovery linac (ERL) is under advanced construction at BNL. The ERL facility is comprised of a five-cell SC Linac plus a half-cell SC photo-injector RF electron gun, both operating at 703.75 MHz. The facility is designed for either a high-current mode of operation up to 0.5 A at 703.75 MHz or a high-bunch-charge mode of 5 nC at 10 MHz bunch frequency. The R&D facility serves a test bed for an envisioned electron-hadron collider, eRHIC. The high-current, high-charge operating parameters make effective higher-order-mode (HOM) damping mandatory, and requires the determination of HOM tolerances for a cavity upgrade. The niobium cavity has been tested at superconducting temperatures and has provided measured quality factors (Q) for a large number of modes. These numbers were used for the estimate of the beam breakup instability (BBU). The facility will be assembled with a highly flexible lattice covering a vast operational parameter space for verification of the estimates and to serve as a test bed for the concepts directed at future projects.
Date: May 23, 2010
Creator: Ben-Zvi, Ilan; Calaga, R.; Hahn, H.; Hammons, L.; Johnson, E.; Kayran, D. et al.
Object Type: Article
System: The UNT Digital Library
Integrated Multiscale Modeling of Molecular Computing Devices (open access)

Integrated Multiscale Modeling of Molecular Computing Devices

Significant advances were made on all objectives of the research program. We have developed fast multiresolution methods for performing electronic structure calculations with emphasis on constructing efficient representations of functions and operators. We extended our approach to problems of scattering in solids, i.e. constructing fast algorithms for computing above the Fermi energy level. Part of the work was done in collaboration with Robert Harrison and George Fann at ORNL. Specific results (in part supported by this grant) are listed here and are described in greater detail. (1) We have implemented a fast algorithm to apply the Green's function for the free space (oscillatory) Helmholtz kernel. The algorithm maintains its speed and accuracy when the kernel is applied to functions with singularities. (2) We have developed a fast algorithm for applying periodic and quasi-periodic, oscillatory Green's functions and those with boundary conditions on simple domains. Importantly, the algorithm maintains its speed and accuracy when applied to functions with singularities. (3) We have developed a fast algorithm for obtaining and applying multiresolution representations of periodic and quasi-periodic Green's functions and Green's functions with boundary conditions on simple domains. (4) We have implemented modifications to improve the speed of adaptive multiresolution algorithms for …
Date: March 23, 2012
Creator: Beylkin, Gregory
Object Type: Report
System: The UNT Digital Library