Progress of Bep Treatments on Nb at JLAB (open access)

Progress of Bep Treatments on Nb at JLAB

Recent experimental results have indicated that Buffered Electropolishing (BEP) is a promising candidate for the next generation of surface treatment technique for Nb superconducting radio frequency (SRF) cavities to be used in particle accelerators. In order to lay the foundation for using BEP as the next generation surface treatment technique for Nb SRF cavities, some fundamental aspects of BEP treatments for Nb have to be investigated. In this report, recent progress on BEP study at JLab is shown. Improvements on the existing vertical BEP are made to allow water cooling from outside of a Nb single cell cavity in addition to cooling provided by acid circulation so that the temperature of the cavity can be stable during processing. Some investigation on the electrolyte mixture was performed to check the aging effect of the electrolyte. It is shown that good polishing results can still be obtained on Nb at a current density of 171 mA/cm when the BEP electrolyte was at the stationary condition and was more than 1.5 years old.
Date: May 1, 2010
Creator: A.T. Wu, S. Jin, R.A. Rimmer,X.Y. Lu, K. Zhao
Object Type: Article
System: The UNT Digital Library
Optical Sideband Generation: a Longitudinal Electron Beam Diagnostic Beyond the Laser Bandwidth Resolution Limit (open access)

Optical Sideband Generation: a Longitudinal Electron Beam Diagnostic Beyond the Laser Bandwidth Resolution Limit

Electro-optic sampling (EOS) is widely used as a technique to measure THz-domain electric field pulses such asthe self-fields of femtosecond electron beams. We present an EOS-based approach for single-shot spectral measurement that excels in simplicity (compatible with fiber integration) and bandwidth coverage (overcomes the laser bandwidth limitation), allowing few-fs electron beams or single-cycle THz pulses to be characterized with conventional picosecond probes. It is shown that the EOS-induced optical sidebands on the narrow-bandwidth optical probe are spectrally-shifted replicas of the THz pulse. An experimental demonstration on a 0-3 THz source is presented.
Date: June 1, 2010
Creator: Laboratory, Lawrence Berkeley National; Tilborg, J. van; Matlis, N. H.; Plateau, G. R. & Leemans, W. P.
Object Type: Article
System: The UNT Digital Library
R&D ERL: Beam dynamics, parameters, and physics to be learned (open access)

R&D ERL: Beam dynamics, parameters, and physics to be learned

The R&D ERL facility at BNL aims to demonstrate CW operation of ERL with average beam current in the range of 0.1-1 ampere, combined with very high efficiency of energy recovery. The ERL is being installed in one of the spacious bays in Bldg. 912 of the RHIC/AGS complex (Fig. 1). The bay is equipped with an overhead crane. The facility has a control room, two service rooms and a shielded ERL cave. The control room is located outside of the bay in a separate building. The single story house is used for a high voltage power supply for 1 MW klystron. The two-story unit houses a laser room, the CW 1 MW klystron with its accessories, most of the power supplies and electronics. The ERL R&D program has been started by the Collider Accelerator Department (C-AD) at BNL as an important stepping-stone for 10-fold increase of the luminosity of the Relativistic Heavy Ion Collider (RHIC) using relativistic electron cooling of gold ion beams with energy of 100 GeV per nucleon. Furthermore, the ERL R&D program extends toward a possibility of using 10-20 GeV ERL for future electron-hadron/heavy ion collider, MeRHIC/eRHIC. These projects are the driving force behind the development …
Date: February 1, 2010
Creator: Kayran, D.
Object Type: Report
System: The UNT Digital Library
Recent Developments on ALICE (Accelerators and Lasers In Combined Experiments) at Daresbury Laboratory (open access)

Recent Developments on ALICE (Accelerators and Lasers In Combined Experiments) at Daresbury Laboratory

Progress made in ALICE (Accelerators and Lasers In Combined Experiments) commissioning and a summary of the latest experimental results are presented in this paper. After an extensive work on beam loading effects in SC RF linac (booster) and linac cavities conditioning, ALICE can now operate in full energy recovery mode at the bunch charge of 40pC, the beam energy of 30MeV and train lengths of up to 100us. This improved operation of the machine resulted in generation of coherently enhanced broadband THz radiation with the energy of several tens of uJ per pulse and in successful demonstration of the Compton Backscattering x-ray source experiment. The next steps in the ALICE scientific programme are commissioning of the IR FEL and start of the research on the first non-scaling FFAG accelerator EMMA. Results from both projects will be also reported.
Date: May 1, 2010
Creator: Saveliev, Y. M.; Buckley, R. K.; Buckley, S. R.; Clarke, J. A.; Corlett, P. A.; Dunning, D. J. et al.
Object Type: Article
System: The UNT Digital Library
A Study of the Use of Jatropha Oil Blends in Boilers (open access)

A Study of the Use of Jatropha Oil Blends in Boilers

Executive Summary: This project investigated the combustion performance of blends of unrefined Jatropha oil and its blends in laboratory boilers. Although a very limited amount of testing blends in distillate oil, ASTM No. 2 oil or heating oil was conducted, the primary interest was in testing the performance of blends with residual ASTM No. 6 oil. The basic idea is to provide a renewable fuel option to residual oil used in space heating and in industrial applications. The intent also was to explore the use of non-edible plant oil and one that might be potentially cheaper than biodiesel. The characteristics of No. 6 oil, such as high viscosity at ambient temperature, which requires it to be kept heated, make the blending with such oils feasible. Jatropha oil is one such oil and there is currently considerable interest building up in its use as a source for making biodiesel and jet fuel. A 10% blend of Jatropha oil with heating oil was burned using a standard burner in a residential boiler. Combustion performance was shown to be comparable with that of burning heating oil by itself with some noticeable differences. Typical heating oil has about 2000 ppm of sulfur, while the …
Date: October 1, 2010
Creator: Krishna, C. R.
Object Type: Report
System: The UNT Digital Library
R&D ERL: HTS Solenoid (open access)

R&D ERL: HTS Solenoid

An innovative feature of the ERL project is the use of a solenoid made with High Temperature Superconductor (HTS) with the Superconducting RF cavity. The HTS solenoid design offers many advantages because of several unique design features. Typically the solenoid is placed outside the cryostat which means that the beam gets significantly defused before a focusing element starts. In the current design, the solenoid is placed inside the cryostat which provides an early focusing structure and thus a significant reduction in the emittance of the electron beam. In addition, taking full advantage of the high critical temperature of HTS, the solenoid has been designed to reach the required field at {approx}77 K, which can be obtained with liquid nitrogen. This significantly reduces the cost of testing and allows a variety of critical pre-tests which would have been prohibitively expensive at 4 K in liquid helium because of the additional requirements of cryostat and associated facilities.
Date: January 1, 2010
Creator: Gupta, R.; Muratore, J. & Plate, S.
Object Type: Report
System: The UNT Digital Library
Presto 4.18 user's guide. (open access)

Presto 4.18 user's guide.

Presto is a Lagrangian, three-dimensional explicit, transient dynamics code that is used to analyze solids subjected to large, suddenly applied loads. The code is designed for a parallel computing environment and for problems with large deformations, nonlinear material behavior, and contact. Presto also has a versatile element library that incorporates both continuum elements and structural elements. This user's guide describes the input for Presto that gives users access to all the current functionality in the code. The environment in which Presto is built allows it to be coupled with other engineering analysis codes. Using a concept called scope, the input structure reflects the fact that Presto can be used in a coupled environment. The user's guide describes how scope is implemented from the outermost to the innermost scopes. Within a given scope, the descriptions of input commands are grouped based on functionality of the code. For example, all material input command lines are described in a chapter of the user's guide for all the material models that can be used in Presto.
Date: September 1, 2010
Creator: Spencer, Benjamin Whiting
Object Type: Report
System: The UNT Digital Library
Advanced Fuels Campaign FY 2010 Accomplishments Report (open access)

Advanced Fuels Campaign FY 2010 Accomplishments Report

The Fuel Cycle Research and Development (FCRD) Advanced Fuels Campaign (AFC) Accomplishment Report documents the high-level research and development results achieved in fiscal year 2010. The AFC program has been given responsibility to develop advanced fuel technologies for the Department of Energy (DOE) using a science-based approach focusing on developing a microstructural understanding of nuclear fuels and materials. The science-based approach combines theory, experiments, and multi-scale modeling and simulation aimed at a fundamental understanding of the fuel fabrication processes and fuel and clad performance under irradiation. The scope of the AFC includes evaluation and development of multiple fuel forms to support the three fuel cycle options described in the Sustainable Fuel Cycle Implementation Plan4: Once-Through Cycle, Modified-Open Cycle, and Continuous Recycle. The word “fuel” is used generically to include fuels, targets, and their associated cladding materials. This document includes a brief overview of the management and integration activities; but is primarily focused on the technical accomplishments for FY-10. Each technical section provides a high level overview of the activity, results, technical points of contact, and applicable references.
Date: December 1, 2010
Creator: Braase, Lori
Object Type: Report
System: The UNT Digital Library
Validation of two ribosomal RNA removal methods for microbial metatranscriptomics (open access)

Validation of two ribosomal RNA removal methods for microbial metatranscriptomics

The predominance of rRNAs in the transcriptome is a major technical challenge in sequence-based analysis of cDNAs from microbial isolates and communities. Several approaches have been applied to deplete rRNAs from (meta)transcriptomes, but no systematic investigation of potential biases introduced by any of these approaches has been reported. Here we validated the effectiveness and fidelity of the two most commonly used approaches, subtractive hybridization and exonuclease digestion, as well as combinations of these treatments, on two synthetic five-microorganism metatranscriptomes using massively parallel sequencing. We found that the effectiveness of rRNA removal was a function of community composition and RNA integrity for these treatments. Subtractive hybridization alone introduced the least bias in relative transcript abundance, whereas exonuclease and in particular combined treatments greatly compromised mRNA abundance fidelity. Illumina sequencing itself also can compromise quantitative data analysis by introducing a G+C bias between runs.
Date: October 1, 2010
Creator: He, Shaomei; Wurtzel, Omri; Singh, Kanwar; Froula, Jeff L; Yilmaz, Suzan; Tringe, Susannah G et al.
Object Type: Article
System: The UNT Digital Library
Laser Interactions in Nanomaterials Synthesis (open access)

Laser Interactions in Nanomaterials Synthesis

Laser interactions with materials have unique advantages to explore the rapid synthesis, processing, and in situ characterization of high quality and novel nanoparticles, nanotubes and nanowires. For example, laser vaporization of solids into background gases provides a wide range of processing conditions for the formation of nanomaterials by both catalyst-free and catalyst-assisted growth processes. Laser interactions with the growing nanomaterials provide remote in situ characterization of their size, structure, and composition with unprecedented temporal resolution. In this article, laser interactions involved in the synthesis of primarily carbon nanostructures are reviewed, including the catalyst-free synthesis of single-walled carbon nanohorns and quantum dots, to the catalyst-assisted growth of single and multi-walled carbon nanotubes.
Date: January 1, 2010
Creator: Geohegan, David B.; Puretzky, Alexander A.; Rouleau, Christopher M.; Jackson, Jeremy Joseph; Eres, Gyula; Xiao, Kai et al.
Object Type: Book
System: The UNT Digital Library
Towards Long-Term Corrosion Resistance in FE Service Environments (open access)

Towards Long-Term Corrosion Resistance in FE Service Environments

The push for carbon capture and sequestration for fossil fuel energy production has materials performance challenges in terms of high temperature oxidation and corrosion resistance. Such challenges will be illustrated with examples from several current technologies that are close to being realized. These include cases where existing technologies are being modified—for example fireside corrosion resulting from increased corrosivity of flue gas in coal boilers refit for oxy-fuel combustion, or steam corrosion resulting from increased temperatures in advanced ultra supercritical steam boilers. New technology concepts also push the high temperature corrosion and oxidation limits—for example the effects of multiple oxidants during the use of high CO2 and water flue gas used as turbine working fluids.
Date: October 1, 2010
Creator: Holcomb, G. R. & Wang, P.
Object Type: Article
System: The UNT Digital Library
Implementation of DOWTHERM A Properties into RELAP5-3D/ATHENA (open access)

Implementation of DOWTHERM A Properties into RELAP5-3D/ATHENA

DOWTHERM A oil is being considered for use as a heat transfer fluid in experiments to help in the design of heat transfer components for the Next Generation Nuclear Plant (NGNP). In conjection with the experiments RELAP5-3D/ATHENA will be used to help design and analyzed the data generated by the experiments. Inorder to use RELAP5-3D the thermophysical properties of DOWTHERM A were implemented into the fluids package of the RELAP5-3D/ATHENA computer propgram. DOWTHERM A properties were implemented in RELAP5-3D/ATHENA using thermophysical property data obtain from a Dow Chemical Company brochure. The data were curve fit and the polynomial equations developed for each required property were input into a fluid property generator. The generated data was then compared to the orginal DOWTHERM A data to verify that the fluid property data generated by the RELAP5-3D/ATHENA code was representitive of the original input data to the generator.
Date: April 1, 2010
Creator: Moore, Richard L.
Object Type: Report
System: The UNT Digital Library
Design considerations for concentrating solar power tower systems employing molten salt. (open access)

Design considerations for concentrating solar power tower systems employing molten salt.

The Solar Two Project was a United States Department of Energy sponsored project operated from 1996 to 1999 to demonstrate the coupling of a solar power tower with a molten nitrate salt as a heat transfer media and for thermal storage. Over all, the Solar Two Project was very successful; however many operational challenges were encountered. In this work, the major problems encountered in operation of the Solar Two facility were evaluated and alternative technologies identified for use in a future solar power tower operating with a steam Rankine power cycle. Many of the major problems encountered can be addressed with new technologies that were not available a decade ago. These new technologies include better thermal insulation, analytical equipment, pumps and values specifically designed for molten nitrate salts, and gaskets resistant to thermal cycling and advanced equipment designs.
Date: September 1, 2010
Creator: Moore, Robert Charles; Siegel, Nathan Phillip; Kolb, Gregory J.; Vernon, Milton E. & Ho, Clifford Kuofei
Object Type: Report
System: The UNT Digital Library
Nucleon Magnetic Moments and Electric Polarizabilities (open access)

Nucleon Magnetic Moments and Electric Polarizabilities

Electromagnetic properties of the nucleon are explored with lattice QCD using a novel technique. Focusing on background electric fields, we show how the electric polarizability can be extracted from nucleon correlation functions. A crucial step concerns addressing contributions from the magnetic moment, which affects the relativistic propagation of nucleons in electric fields. By properly handing these contributions, we can determine both magnetic moments and electric po larizabilities. Lattice results from anisotropic clover lattices are presented. Our method is not limited to the neutron; we show results for the proton as well.
Date: June 1, 2010
Creator: Detmold, W. & Walker-Loud, A.
Object Type: Article
System: The UNT Digital Library
Environmental geographic information system. (open access)

Environmental geographic information system.

This document describes how the Environmental Geographic Information System (EGIS) was used, along with externally received data, to create maps for the Site-Wide Environmental Impact Statement (SWEIS) Source Document project. Data quality among the various classes of geographic information system (GIS) data is addressed. A complete listing of map layers used is provided.
Date: August 1, 2010
Creator: Peek, Dennis; Helfrich, Donald Alan & Gorman, Susan
Object Type: Report
System: The UNT Digital Library
Hydrogen-Bromine Flow Battery: Hydrogen Bromine Flow Batteries for Grid Scale Energy Storage (open access)

Hydrogen-Bromine Flow Battery: Hydrogen Bromine Flow Batteries for Grid Scale Energy Storage

GRIDS Project: LBNL is designing a flow battery for grid storage that relies on a hydrogen-bromine chemistry which could be more efficient, last longer and cost less than today’s lead-acid batteries. Flow batteries are fundamentally different from traditional lead-acid batteries because the chemical reactants that provide their energy are stored in external tanks instead of inside the battery. A flow battery can provide more energy because all that is required to increase its storage capacity is to increase the size of the external tanks. The hydrogen-bromine reactants used by LBNL in its flow battery are inexpensive, long lasting, and provide power quickly. The cost of the design could be well below $100 per kilowatt hour, which would rival conventional grid-scale battery technologies.
Date: October 1, 2010
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Methane hydrate distribution from prolonged and repeated formation in natural and compacted sand samples: X-ray CT observations (open access)

Methane hydrate distribution from prolonged and repeated formation in natural and compacted sand samples: X-ray CT observations

To study physical properties of methane gas hydrate-bearing sediments, it is necessary to synthesize laboratory samples due to the limited availability of cores from natural deposits. X-ray computed tomography (CT) and other observations have shown gas hydrate to occur in a number of morphologies over a variety of sediment types. To aid in understanding formation and growth patterns of hydrate in sediments, methane hydrate was repeatedly formed in laboratory-packed sand samples and in a natural sediment core from the Mount Elbert Stratigraphic Test Well. CT scanning was performed during hydrate formation and decomposition steps, and periodically while the hydrate samples remained under stable conditions for up to 60 days. The investigation revealed the impact of water saturation on location and morphology of hydrate in both laboratory and natural sediments during repeated hydrate formations. Significant redistribution of hydrate and water in the samples was observed over both the short and long term.
Date: July 1, 2010
Creator: Rees, E.V.L.; Kneafsey, T.J. & Seol, Y.
Object Type: Article
System: The UNT Digital Library
B physics at CDF - the Beauty of hadron collisions (open access)

B physics at CDF - the Beauty of hadron collisions

The CDF experiment at the Tevatron p{bar p} collider established that extensive and detailed exploration of the b-quark dynamics is possible in hadron collisions, with results competitive and supplementary to those from e{sup +}e{sup -} colliders. This provides an unique, rich, and highly rewarding program that is currently reaching full maturity. I report a few recent world-leading results on rare decays, CP-violation in B{sub s}{sup 0} mixing, and b {yields} s penguin decays.
Date: November 1, 2010
Creator: Tonelli, Diego
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 1, 2010
Creator: B. Hall,G. Burt,C. Lingwood,Robert Rimmer,Haipeng Wang; Hall, B.; Burt, G.; Lingwood, C.; Rimmer, Robert & Wang, Haipeng
Object Type: Article
System: The UNT Digital Library
A Sterile-Neutrino Search with the MINOS Experiment (open access)

A Sterile-Neutrino Search with the MINOS Experiment

The MINOS experiment is a long-baseline neutrino oscillation experiment in the the NuMI beamline at Fermilab, USA. Using a near detector at 1 km distance from the neutrino production target, and a far detector at 735 km from the target, it is designed primarily to measure the disappearance of muon neutrinos. This thesis presents an analysis using MINOS data of the possibility of oscil- lation of the neutrinos in the NuMI beam to a hypothetical sterile flavour, which would have no Standard Model couplings. Such oscillations would result in a deficit in the neutral current interaction rate in the MINOS far detector relative to the expectation derived from the near detector data. The method used to identify neutral current and charged current events in the MINOS detectors is described and a new method of predicting and fitting the far detector spectrum presented, along with the effects of systematic uncertainties on the sterile neutrino oscillation analysis. Using this analysis, the fraction f{sub s} of the disappearing neutrinos that go to steriles is constrained to be below 0.15 at the 90% confidence level in the absence of electron neutrino appearance in the NuMI beam. With electron appearance at the CHOOZ limit, f{sub …
Date: September 1, 2010
Creator: Rodrigues, Philip
Object Type: Thesis or Dissertation
System: The UNT Digital Library
DESIGN AND SHIELDING OF A BEAM LINE FROM ELENA TO ATRAP USING ELECTROSTATIC QUADRUPOLE LENSES AND BENDS (open access)

DESIGN AND SHIELDING OF A BEAM LINE FROM ELENA TO ATRAP USING ELECTROSTATIC QUADRUPOLE LENSES AND BENDS

The construction of the Extra Low ENergy Antiprotons (ELENA) upgrade to the Antiproton Decelerator (AD) ring has been proposed at CERN to produce a greatly increased current of low-energy antiprotons for various experiments including anti-hydrogen studies. This upgrade involves the addition of a small storage ring and electrostatic beam lines. The 5.3-MeV antiproton beams from AD are decelerated down to 100 keV in the compact ring and transported to each experimental apparatus. In this paper, we describe an electrostatic beam line from the ELENA ring to the ATRAP experimental apparatus and magnetic shielding of the low-energy beam line against the ATRAP superconducting solenoid magnet. A possible rough conceptual design of this system is displayed.
Date: September 1, 2010
Creator: Yuri, Yosuke & Lee, Edward P.
Object Type: Article
System: The UNT Digital Library
Uncertainty quantification and validation of combined hydrological and macroeconomic analyses. (open access)

Uncertainty quantification and validation of combined hydrological and macroeconomic analyses.

Changes in climate can lead to instabilities in physical and economic systems, particularly in regions with marginal resources. Global climate models indicate increasing global mean temperatures over the decades to come and uncertainty in the local to national impacts means perceived risks will drive planning decisions. Agent-based models provide one of the few ways to evaluate the potential changes in behavior in coupled social-physical systems and to quantify and compare risks. The current generation of climate impact analyses provides estimates of the economic cost of climate change for a limited set of climate scenarios that account for a small subset of the dynamics and uncertainties. To better understand the risk to national security, the next generation of risk assessment models must represent global stresses, population vulnerability to those stresses, and the uncertainty in population responses and outcomes that could have a significant impact on U.S. national security.
Date: September 1, 2010
Creator: Hernandez, Jacquelynne; Parks, Mancel Jordan; Jennings, Barbara Joan; Kaplan, Paul Garry; Brown, Theresa Jean & Conrad, Stephen Hamilton
Object Type: Report
System: The UNT Digital Library
Tectonic Versus Volcanic Origin of the Summit Depression at Medicine Lake Volcano, California (open access)

Tectonic Versus Volcanic Origin of the Summit Depression at Medicine Lake Volcano, California

Medicine Lake Volcano is a Quaternary shield volcano located in a tectonically complex and active zone at the transition between the Basin and Range Province and the Cascade Range of the Pacific Province. The volcano is topped by a 7x12 km elliptical depression surrounded by a discontinuous constructional ring of basaltic to rhyolitic lava flows. This thesis explores the possibility that the depression may have formed due to regional extension (rift basin) or dextral shear (pull-apart basin) rather than through caldera collapse and examines the relationship between regional tectonics and localized volcanism. Existing data consisting of temperature and magnetotelluric surveys, alteration mineral studies, and core logging were compiled and supplemented with additional core logging, field observations, and fault striae studies in paleomagnetically oriented core samples. These results were then synthesized with regional fault data from existing maps and databases. Faulting patterns near the caldera, extension directions derived from fault striae P and T axes, and three-dimensional temperature and alteration mineral models are consistent with slip across arcuate ring faults related to magma chamber deflation during flank eruptions and/or a pyroclastic eruption at about 180 ka. These results are not consistent with a rift or pull-apart basin. Limited subsidence can be …
Date: May 1, 2010
Creator: Gwynn, Mark Leon
Object Type: Report
System: The UNT Digital Library
Idaho National Laboratory Integrated Safety Management System 2010 Effectiveness Review and Declaration Report (open access)

Idaho National Laboratory Integrated Safety Management System 2010 Effectiveness Review and Declaration Report

Idaho National Laboratory completes an annual Integrated Safety Management System effectiveness review per 48 CFR 970.5223-1 “Integration of Environment, Safety and Health into Work Planning and Execution.” The annual review assesses ISMS effectiveness, provides feedback to maintain system integrity, and helps identify target areas for focused improvements and assessments for the following year. Using one of the three Department of Energy (DOE) descriptors in DOE M 450.4-1 regarding the state of ISMS effectiveness during Fiscal Year (FY) 2010, the information presented in this review shows that INL achieved “Effective Performance.”
Date: December 1, 2010
Creator: Haney, Thomas J.
Object Type: Report
System: The UNT Digital Library