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Bacterial Community Profiling of Milk Samples as a Means to Understand Culture-Negative Bovine Clinical Mastitis (open access)

Bacterial Community Profiling of Milk Samples as a Means to Understand Culture-Negative Bovine Clinical Mastitis

Article discussing a study that was conducted to understand the basis of a bacterial infection that is common among dairy cows.
Date: April 25, 2013
Creator: Kuehn, Joanna S.; Gorden, Patrick J.; Munro, Daniel; Rong, Ruichen; Dong, Qunfeng; Plummer, Paul J. et al.
System: The UNT Digital Library
Thermochemical Investigations of Solute Transfer into Ionic Solvents: Updated Abraham Model Equation Coefficients for Solute Activity Coefficient and Partition Coefficient Predictions (open access)

Thermochemical Investigations of Solute Transfer into Ionic Solvents: Updated Abraham Model Equation Coefficients for Solute Activity Coefficient and Partition Coefficient Predictions

Article on thermochemical investigations of solute transfer into ionic liquid solvents and updated Abraham model equation coefficients for solute activity coefficient and partition coefficient predictions.
Date: February 25, 2014
Creator: Stephens, Timothy W.; Chou, Vicky; Quay, Amanda N.; Shen, Connie; Dabadge, Nishu; Tian, Amy et al.
System: The UNT Digital Library
Optomechanical Design for Precision Lens Positioning and Mounting (open access)

Optomechanical Design for Precision Lens Positioning and Mounting

This article presents a lens positioning and mounting in a few microns accuracy using a kinematic mount module.
Date: August 25, 2016
Creator: Wang, Shuping; Zhang, Chi; Alt, Mark; Davis, Colleen; Gardner, Michael L. & Ji, Zheng
System: The UNT Digital Library
Halo Formation And Emittance Growth of Positron Beams in Plasmas (open access)

Halo Formation And Emittance Growth of Positron Beams in Plasmas

An ultrarelativistic 28.5 GeV, 700-{micro}m-long positron bunch is focused near the entrance of a 1.4-m-long plasma with a density n{sub e} between {approx}10{sup 13} and {approx}5 x 10{sup 14} cm{sup -3}. Partial neutralization of the bunch space charge by the mobile plasma electrons results in a reduction in transverse size by a factor of {approx}3 in the high emittance plane of the beam {approx}1 m downstream from the plasma exit. As n{sub e} increases, the formation of a beam halo containing {approx}40% of the total charge is observed, indicating that the plasma focusing force is nonlinear. Numerical simulations confirm these observations. The bunch with an incoming transverse size ratio of {approx}3 and emittance ratio of {approx}5 suffers emittance growth and exits the plasma with approximately equal sizes and emittances.
Date: October 25, 2011
Creator: Muggli, P.; Blue, B. E.; Clayton, C. E.; Decker, F. J.; Hogan, M. J.; Huang, C. et al.
System: The UNT Digital Library
Performance Validation and Scaling of a Capillary Membrane Solid-Liquid Separation System (open access)

Performance Validation and Scaling of a Capillary Membrane Solid-Liquid Separation System

Algaeventure Systems (AVS) has previously demonstrated an innovative technology for dewatering algae slurries that dramatically reduces energy consumption by utilizing surface physics and capillary action. Funded by a $6M ARPA-E award, transforming the original Harvesting, Dewatering and Drying (HDD) prototype machine into a commercially viable technology has required significant attention to material performance, integration of sensors and control systems, and especially addressing scaling issues that would allow processing extreme volumes of algal cultivation media/slurry. Decoupling the harvesting, dewatering and drying processes, and addressing the rate limiting steps for each of the individual steps has allowed for the development individual technologies that may be tailored to the specific needs of various cultivation systems. The primary performance metric used by AVS to assess the economic viability of its Solid-Liquid Separation (SLS) dewatering technology is algae mass production rate as a function of power consumption (cost), cake solids/moisture content, and solids capture efficiency. An associated secondary performance metric is algae mass loading rate which is dependent on hydraulic loading rate, area-specific hydraulic processing capacity (gpm/in2), filter:capillary belt contact area, and influent algae concentration. The system is capable of dewatering 4 g/L (0.4%) algae streams to solids concentrations up to 30% with capture efficiencies …
Date: October 25, 2011
Creator: Rogers, S.; Cook, J.; Juratovac, J.; Goodwillie, J.; Burke, T. & Stuart, B., ed.
System: The UNT Digital Library
IMPROVEMENT OF CdMnTe DETECTOR PERFORMANCE BY MnTe PURIFICATION (open access)

IMPROVEMENT OF CdMnTe DETECTOR PERFORMANCE BY MnTe PURIFICATION

Residual impurities in manganese (Mn) are a big obstacle to obtaining high-performance CdMnTe (CMT) X-ray and gamma-ray detectors. Generally, the zone-refining method is an effective way to improve the material's purity. In this work, we purified the MnTe compounds combining the zone-refining method with molten Te, which has a very high solubility for most impurities. We confirmed the improved purity of the material by glow-discharge mass spectrometry (GDMS). We also found that CMT crystals from a multiply-refined MnTe source, grown by the vertical Bridgman method, yielded better performing detectors.
Date: April 25, 2011
Creator: Kim, K. H.; Bolotnikov, A. E.; Camarda, G. S.; Tappero, R.; Hossain, A.; Cui, Y. et al.
System: The UNT Digital Library
Nonlinear pulse propagation and phase velocity of laser-driven plasma waves (open access)

Nonlinear pulse propagation and phase velocity of laser-driven plasma waves

Laser evolution and plasma wave excitation by a relativistically-intense short-pulse laser in underdense plasma are investigated in the broad pulse limit, including the effects of pulse steepening, frequency red-shifting, and energy depletion. The nonlinear plasma wave phase velocity is shown to be significantly lower than the laser group velocity and further decreases as the pulse propagates owing to laser evolution. This lowers the thresholds for trapping and wavebreaking, and reduces the energy gain and efficiency of laser-plasma accelerators that use a uniform plasma profile.
Date: March 25, 2011
Creator: Schroeder, Carl B.; Benedetti, Carlo; Esarey, Eric & Leemans, Wim
System: The UNT Digital Library
PHASE II VAULT TESTING OF THE ARGONNE RFID SYSTEM (open access)

PHASE II VAULT TESTING OF THE ARGONNE RFID SYSTEM

The U.S. Department of Energy (DOE) (Environmental Management [EM], Office of Packaging and Transportation [EM-45]) Packaging and Certification Program (DOE PCP) has developed a Radio Frequency Identification (RFID) tracking and monitoring system, called ARG-US, for the management of nuclear materials packages during transportation and storage. The performance of the ARG-US RFID equipment and system has been fully tested in two demonstration projects in April 2008 and August 2009. With the strong support of DOE-SR and DOE PCP, a field testing program was completed in Savannah River Site's K-Area Material Storage (KAMS) Facility, an active Category I Plutonium Storage Facility, in 2010. As the next step (Phase II) of continued vault testing for the ARG-US system, the Savannah River Site K Area Material Storage facility has placed the ARG-US RFIDs into the 910B storage vault for operational testing. This latest version (Mark III) of the Argonne RFID system now has the capability to measure radiation dose and dose rate. This paper will report field testing progress of the ARG-US RFID equipment in KAMS, the operability and reliability trend results associated with the applications of the system, and discuss the potential benefits in enhancing safety, security and materials accountability. The purpose of …
Date: June 25, 2012
Creator: Willoner, T.; Turlington, R. & Koenig, R.
System: The UNT Digital Library
SINGLE-SHELL TANKS LEAK INTEGRITY ELEMENTS/SX FARM LEAK CAUSES AND LOCATIONS - 12127 (open access)

SINGLE-SHELL TANKS LEAK INTEGRITY ELEMENTS/SX FARM LEAK CAUSES AND LOCATIONS - 12127

Washington River Protection Solutions, LLC (WRPS) developed an enhanced single-shell tank (SST) integrity project in 2009. An expert panel on SST integrity was created to provide recommendations supporting the development of the project. One primary recommendation was to expand the leak assessment reports (substitute report or LD-1) to include leak causes and locations. The recommendation has been included in the M-045-9IF Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) as one of four targets relating to SST leak integrity. The 241-SX Farm (SX Farm) tanks with leak losses were addressed on an individual tank basis as part of LD-1. Currently, 8 out of 23 SSTs that have been reported to having a liner leak are located in SX Farm. This percentage was the highest compared to other tank farms which is why SX Farm was analyzed first. The SX Farm is comprised of fifteen SSTs built 1953-1954. The tanks are arranged in rows of three tanks each, forming a cascade. Each of the SX Farm tanks has a nominal I-million-gal storage capacity. Of the fifteen tanks in SX Farm, an assessment reported leak losses for the following tanks: 241-SX-107, 241-SX-108, 241-SX-109, 241-SX-111, 241-SX-112, 241-SX-113, 241-SX-114 and 241-SX-115. The method …
Date: January 25, 2012
Creator: TJ, VENETZ; D, WASHENFELDER; J, JOHNSON & C, GIRARDOT
System: The UNT Digital Library
Real-time Studies of Shocked Polycrystalline Materials with Single-Pulse X-ray Diffraction (open access)

Real-time Studies of Shocked Polycrystalline Materials with Single-Pulse X-ray Diffraction

Characteristic K-α x-rays used for single-pulse XRD are conventionally produced by a 37-stage high-voltage Marx pulse generator coupled to a vacuum needle-and-washer x-ray diode via coaxial transmission line. A large field-of-view x-ray image plate detection system typically enables observation of several Debye-Scherrer rings. Recently, we have developed a fiber-optic reducer, coupled to a CCD camera, to obtain low-noise, large field-of-view images. The direct beam spot is produced by bremsstrahlung radiation attenuated by a twomillimeter tungsten beam stop. Determination of the direct beam position is necessary to perform the ring integration.
Date: May 25, 2011
Creator: Morgan, Dane V.
System: The UNT Digital Library
Field Tolerances for the Triplet Quadrupoles of the LHC High Luminosity Lattice (open access)

Field Tolerances for the Triplet Quadrupoles of the LHC High Luminosity Lattice

It has been proposed to implement the so-called Achromatic Telescopic Squeezing (ATS) scheme in the LHC high luminosity (HL) lattice to reduce beta functions at the Interaction Points (IP) up to a factor of 8. As a result, the nominal 4.5 km peak beta functions reached in the Inner Triplets (IT) at collision will be increased by the same factor. This, therefore, justifies the installation of new, larger aperture, superconducting IT quadrupoles. The higher beta functions will enhance the effects of the triplet quadrupole field errors leading to smaller beam dynamic aperture (DA). To maintain the acceptable DA, the effects of the triplet field errors must be re-evaluated, thus specifying new tolerances. Such a study has been performed for the so-called '4444' collision option of the HL-LHC layout version SLHCV3.01, where the IP beta functions are reduced by a factor of 4 in both planes with respect to a pre-squeezed value of 60 cm at two collision points. The dynamic aperture calculations were performed using SixTrack. The impact on the triplet field quality is presented.
Date: June 25, 2012
Creator: Nosochkov, Yuri; Cai, Y.; Jiao, Y.; Wang, M. H.; Fartoukh, S.; Giovannozzi, M. et al.
System: The UNT Digital Library
Surface Engineering of Corrosion, Environmental Fracture, Cavitation & Impingement Resistant Materials (open access)

Surface Engineering of Corrosion, Environmental Fracture, Cavitation & Impingement Resistant Materials

None
Date: July 25, 2012
Creator: Farmer, J; Rukbenchik, A; Menon, S; McNelley, T & Hackel, L
System: The UNT Digital Library
Electronic Structure of CeFeAsO1-xFx (x=0, 0.11/x=0.12) compounds (open access)

Electronic Structure of CeFeAsO1-xFx (x=0, 0.11/x=0.12) compounds

We report an extensive study on the intrinsic bulk electronic structure of the high-temperature superconductor CeFeAsO{sub 0.89}F{sub 0.11} and its parent compound CeFeAsO by soft and hard x-ray photoemission, x-ray absorption and soft-x-ray emission spectroscopies. The complementary surface/bulk probing depth, and the elemental and chemical sensitivity of these techniques allows resolving the intrinsic electronic structure of each element and correlating it with the local structure, which has been probed by extended-x-ray absorption fine structure spectroscopy. The measurements indicate a predominant 4f{sup 1} (i.e. Ce{sup 3+}) initial state configuration for Cerium and an effective valence-band-to-4f charge-transfer screening of the core hole. The spectra also reveal the presence of a small Ce f{sup 0} initial state configuration, which we assign to the occurrence of an intermediate valence state. The data reveal a reasonably good agreement with the partial density of states as obtained in standard density functional calculations over a large energy range. Implications for the electronic structure of these materials are discussed.
Date: January 25, 2011
Creator: Bondino, F.; Magnano, E.; Booth, C. H.; Offi, F.; Panaccione, G.; Malvestuto, M. et al.
System: The UNT Digital Library
A luminescent nanocrystal stress gauge (open access)

A luminescent nanocrystal stress gauge

Microscale mechanical forces can determine important outcomes ranging from the site of material fracture to stem cell fate. However, local stresses in a vast majority of systems cannot be measured due to the limitations of current techniques. In this work, we present the design and implementation of the CdSe/CdS core/shell tetrapod nanocrystal, a local stress sensor with bright luminescence readout. We calibrate the tetrapod luminescence response to stress, and use the luminescence signal to report the spatial distribution of local stresses in single polyester fibers under uniaxial strain. The bright stress-dependent emission of the tetrapod, its nanoscale size, and its colloidal nature provide a unique tool that may be incorporated into a variety of micromechanical systems including materials and biological samples to quantify local stresses with high spatial resolution.
Date: October 25, 2010
Creator: Choi, Charina; Koski, Kristie; Olson, Andrew & Alivisatos, Paul
System: The UNT Digital Library
Novel deflecting cavity design for eRHIC (open access)

Novel deflecting cavity design for eRHIC

To prevent significant loss of the luminosity due to large crossing angle in the future ERL based Electron Ion Collider at BNL (eRHIC), there is a demand for crab cavities. In this article, we will present a novel design of the deflecting/crabbing 181 MHz superconducting RF cavity that will fulfil the requirements of eRHIC. The quarter-wave resonator structure of the new cavity possesses many advantages, such as compact size, high R{sub t}/Q, the absence of the same order mode and lower order mode, and easy higher order mode damping. We will present the properties and characteristics of the new cavity in detail. As the accelerator systems grow in complexity, developing compact and efficient deflecting cavities is of great interest. Such cavities will benefit situations where the beam line space is limited. The future linac-ring type electron-ion collider requires implementation of a crab-crossing scheme for both beams at the interaction region. The ion beam has a long bunches and high rigidity. Therefore, it requires a low frequency, large kicking angle deflector. The frequency of the deflecting mode for the current collider design is 181 MHz, and the deflecting angle is {approx}5 mrad for each beam. At such low frequency, the previous …
Date: July 25, 2011
Creator: Wu, Q.; Belomestnykh, S. & Ben-Zvi, Ilan
System: The UNT Digital Library
Cosmography From Two-Image Lens Systems: Overcoming the Lens Profile Slope Degeneracy (open access)

Cosmography From Two-Image Lens Systems: Overcoming the Lens Profile Slope Degeneracy

None
Date: April 25, 2013
Creator: Suyu, S.H. & /UC, Santa Barbara /KIPAC, Menlo Park
System: The UNT Digital Library
Status of High Power Tests of Normal Conducting Single-Cell Standing Wave Structures (open access)

Status of High Power Tests of Normal Conducting Single-Cell Standing Wave Structures

Our experiments are directed toward the understanding of the physics of rf breakdown in systems that can be used to accelerate electron beams at {approx}11.4 GHz. The structure geometries have apertures, stored energy per cell, and rf pulse duration close to that of the NLC or CLIC. The breakdown rate is the main parameter that we use to compare rf breakdown behavior for different structures at a given set of rf pulse parameters (pulse shape and peak power) at 60 Hz repetition rate. In our experiments, the typical range of the breakdown rate is from one per few hours to {approx}100 per hour. To date we have tested 29 structures. We consistently found that after the initial conditioning, the behavior of the breakdown rate is reproducible for structures of the same geometry and material, and the breakdown rate dependence on peak magnetic fields is stronger than on peak surface electric fields for structures of different geometries. Below we report the main results from tests of seven structures made from hard copper, soft copper alloys and hard-copper alloys. Additional details on these and other structures will be discussed in future publications.
Date: June 25, 2012
Creator: Dolgashev, Valery; Tantawi, Sami; Yeremian, Anahid; Higashi, Yasuo & Spataro, Bruno
System: The UNT Digital Library
NEW RESULTS ON THE LASER PRODUCED RELATIVISTIC ELECTRON-POSITRON PAIR PLASMA RESEARCH (open access)

NEW RESULTS ON THE LASER PRODUCED RELATIVISTIC ELECTRON-POSITRON PAIR PLASMA RESEARCH

None
Date: March 25, 2013
Creator: Chen, H
System: The UNT Digital Library
2010 INORGANIC CHEMISTRY GORDON RESEARCH CONFERENCE JUNE 20 - 25, 2010 (open access)

2010 INORGANIC CHEMISTRY GORDON RESEARCH CONFERENCE JUNE 20 - 25, 2010

The Inorganic Chemistry GRC is one of the longest-standing of the GRCs, originating in 1951. Over the years, this conference has played a role in spawning many other GRCs in specialized fields, due to the involvement of elements from most of the periodic table. These include coordination, organometallic, main group, f-element, and solid state chemistries; materials science, catalysis, computational chemistry, nanotechnology, bioinorganic, environmental, and biomedical sciences just to name a few. The 2010 Inorganic Chemistry GRC will continue this tradition, where scientists at all levels from academic, industrial, and national laboratories meet to define the important problems in the field and to highlight emerging opportunities through exchange of ideas and discussion of unpublished results. Invited speakers will present on a wide variety of topics, giving attendees a look at areas both inside and outside of their specialized areas of interest. In addition to invited speakers, the poster sessions at GRCs are a key feature of the conference. All conferees at the Inorganic Chemistry GRC are invited to present a poster on their work, and here the informal setting promotes the free exchange of ideas and fosters new relationships. As in previous years, we will offer poster presenters the opportunity to …
Date: June 25, 2010
Creator: LOCKEMEYER, JOHN
System: The UNT Digital Library
Flammability Control In A Nuclear Waste Vitrification System (open access)

Flammability Control In A Nuclear Waste Vitrification System

The Defense Waste Processing Facility at the Savannah River Site processes high-level radioactive waste from the processing of nuclear materials that contains dissolved and precipitated metals and radionuclides. Vitrification of this waste into borosilicate glass for ultimate disposal at a geologic repository involves chemically modifying the waste to make it compatible with the glass melter system. Pretreatment steps include removal of excess aluminum by dissolution and washing, and processing with formic and nitric acids to: 1) adjust the reduction-oxidation (redox) potential in the glass melter to reduce radionuclide volatility and improve melt rate; 2) adjust feed rheology; and 3) reduce by steam stripping the amount of mercury that must be processed in the melter. Elimination of formic acid in pretreatment has been studied to eliminate the production of hydrogen in the pretreatment systems, which requires nuclear grade monitoring equipment. An alternative reductant, glycolic acid, has been studied as a substitute for formic acid. However, in the melter, the potential for greater formation of flammable gases exists with glycolic acid. Melter flammability is difficult to control because flammable mixtures can be formed during surges in offgases that both increase the amount of flammable species and decrease the temperature in the vapor …
Date: July 25, 2013
Creator: Zamecnik, John R.; Choi, Alexander S.; Johnson, Fabienne C.; Miller, Donald H.; Lambert, Daniel P.; Stone, Michael E. et al.
System: The UNT Digital Library
PILOT SCALE TESTING OF MONOSODIUM TITANATE MIXING FOR THE SRS SMALL COLUMN ION EXCHANGE PROCESS - 11224 (open access)

PILOT SCALE TESTING OF MONOSODIUM TITANATE MIXING FOR THE SRS SMALL COLUMN ION EXCHANGE PROCESS - 11224

The Small Column Ion Exchange (SCIX) process is being developed to remove cesium, strontium, and select actinides from Savannah River Site (SRS) Liquid Waste using an existing waste tank (i.e., Tank 41H) to house the process. Savannah River National Laboratory (SRNL) is conducting pilot-scale mixing tests to determine the pump requirements for suspending monosodium titanate (MST), crystalline silicotitanate (CST), and simulated sludge. The purpose of this pilot scale testing is to determine the requirements for the pumps to suspend the MST particles so that they can contact the strontium and actinides in the liquid and be removed from the tank. The pilot-scale tank is a 1/10.85 linear scaled model of SRS Tank 41H. The tank diameter, tank liquid level, pump nozzle diameter, pump elevation, and cooling coil diameter are all 1/10.85 of their dimensions in Tank 41H. The pump locations correspond to the proposed locations in Tank 41H by the SCIX program (Risers B5 and B2 for two pump configurations and Risers B5, B3, and B1 for three pump configurations). The conclusions from this work follow: (i) Neither two standard slurry pumps nor two quad volute slurry pumps will provide sufficient power to initially suspend MST in an SRS waste …
Date: January 25, 2011
Creator: Poirier, M.; Restivo, M.; Williams, M.; Herman, D. & Steeper, T.
System: The UNT Digital Library
Case Study of the Failure of two 13.8kV Control & Metering Transformers that caused significant Equipment Damage (open access)

Case Study of the Failure of two 13.8kV Control & Metering Transformers that caused significant Equipment Damage

The degradation and failure of cast-coil epoxy windings within 13.8kV control power transformers and metering potential transformers has been shown to be dangerous to both equipment and personnel, even though best industrial design practices were followed. Accident scenes will be examined for two events at a U.S. Department of Energy laboratory. Failure modes will be explained and current design practices discussed with changes suggested to prevent a recurrence and to minimize future risk. New maintenance philosophies utilizing partial discharge testing of the transformers as a prediction of end-of-life will be examined.
Date: August 25, 2011
Creator: Dreifuerst, G R; Chew, D B; Mangonon, H L & Swyers, P W
System: The UNT Digital Library
Design Calculations For NIF Convergent Ablator Experiments (open access)

Design Calculations For NIF Convergent Ablator Experiments

The NIF convergent ablation tuning effort is underway. In the early experiments, we have discovered that the design code simulations over-predict the capsule implosion velocity and shock flash rhor, but under-predict the hohlraum x-ray flux measurements. The apparent inconsistency between the x-ray flux and radiography data implies that there are important unexplained aspects of the hohlraum and/or capsule behavior.
Date: October 25, 2011
Creator: Olson, R E; Hicks, D G; Meezan, N B; Callahan, D A; Landen, O L; Jones, O S et al.
System: The UNT Digital Library
High-harmonic Fast Wave Heating and Current Drive Results for Deuterium H-mode Plasmas in the National Spherical Torus Experiment (open access)

High-harmonic Fast Wave Heating and Current Drive Results for Deuterium H-mode Plasmas in the National Spherical Torus Experiment

A critical research goal for the spherical torus (ST) program is to initiate, ramp-up, and sustain a discharge without using the central solenoid. Simulations of non-solenoidal plasma scenarios in the National Spherical Torus Experiment (NSTX) [1] predict that high-harmonic fast wave (HHFW) heating and current drive (CD) [2] can play an important roll in enabling fully non-inductive (fNI {approx} 1) ST operation. The NSTX fNI {approx} 1 strategy requires 5-6 MW of HHFW power (PRF) to be coupled into a non-inductively generated discharge [3] with a plasma current, Ip {approx} 250-350 kA, driving the plasma into an HHFW H-mode with Ip {approx} 500 kA, a level where 90 keV deuterium neutral beam injection (NBI) can heat the plasma and provide additional CD. The initial approach on NSTX has been to heat Ip {approx} 300 kA, inductively heated, deuterium plasmas with CD phased HHFW power [2], in order to drive the plasma into an H-mode with fNI {approx} 1.
Date: July 25, 2012
Creator: Taylor, G.; Bonoli, P. T.; Harvey, R. W.; Hosea, J. C.; Jaeger, E. F.; LeBlanc, B. P. et al.
System: The UNT Digital Library