Non-destructive Identification of Individual Leukemia Cells by Optical Trapping Raman Spectroscopy (open access)

Non-destructive Identification of Individual Leukemia Cells by Optical Trapping Raman Spectroscopy

Currently, a combination of technologies is typically required to assess the malignancy of cancer cells. These methods often lack the specificity and sensitivity necessary for early, accurate diagnosis. Here we demonstrate using clinical samples the application of laser trapping Raman spectroscopy as a novel approach that provides intrinsic biochemical markers for the noninvasive detection of individual cancer cells. The Raman spectra of live, hematopoietic cells provide reliable molecular fingerprints that reflect their biochemical composition and biology. Populations of normal T and B lymphocytes from four healthy individuals, and cells from three leukemia patients were analyzed, and multiple intrinsic Raman markers associated with DNA and protein vibrational modes have been identified that exhibit excellent discriminating power for cancer cell identification. A combination of two multivariate statistical methods, principal component analysis (PCA) and linear discriminant analysis (LDA), was used to confirm the significance of these markers for identifying cancer cells and classifying the data. The results indicate that, on average, 95% of the normal cells and 90% of the patient cells were accurately classified into their respective cell types. We also provide evidence that these markers are unique to cancer cells and not purely a function of differences in their cellular activation.
Date: March 5, 2007
Creator: Chan, J W; Taylor, D S; Lane, S; Zwerdling, T; Tuscano, J & Huser, T
Object Type: Article
System: The UNT Digital Library
WIPP Facility Work Plan for Solid Waste Management Units and Areas of Concern (open access)

WIPP Facility Work Plan for Solid Waste Management Units and Areas of Concern

his 2002 Facility Work Plan (FWP) has been prepared as required by Module VII,Permit Condition VII.U.3 of the Waste Isolation Pilot Plant (WIPP) Hazardous Waste Facility Permit, NM4890139088-TSDF (the Permit) (New Mexico Environment Department [NMED], 1999a), and incorporates comments from the NMED received onDecember 6, 2000 (NMED, 2000a). This February 2002 FWP describes the program-matic facility-wide approach to future investigations at Solid Waste Management Units (SWMU) and Areas of Concern (AOC) specified in the Permit. The Permittees are evaluating data from previous investigations of the SWMUs and AOCs against the mostrecent guidance proposed by the NMED. Based on these data, and completion of the August 2001 sampling requested by the NMED, the Permittees expect that no further sampling will be required and that a request for No Further Action (NFA) at the SWMUs and AOCs will be submitted to the NMED. This FWP addresses the current Permit requirements. It uses the results of previous investigations performed at WIPP and expands the investigations as required by the Permit. As an alternative to the Resource Conservation and Recovery Act (RCRA)Facility Investigation (RFI) specified in Module VII of the Permit, current NMED guidance identifies an Accelerated Corrective Action Approach (ACAA) that may beused …
Date: March 5, 2002
Creator: Westinghouse TRU Solutions LLC
Object Type: Report
System: The UNT Digital Library
Mechanism of Phosphorus Removal from Hanford Tank Sludge by Caustic Leaching (open access)

Mechanism of Phosphorus Removal from Hanford Tank Sludge by Caustic Leaching

Two experiments were conducted to explore the mechanism by which phosphorus is removed from Hanford tank sludge by caustic leaching. In the first experiment, a series of phosphate salts were treated with 3 M NaOH under conditions prototypic of the actual leaching process to be performed in the Waste Treatment and Immobilization Plant (WTP). The phosphates used were aluminum phosphate, bismuth phosphate, chromium(III) phosphate, and -tri-calcium phosphate; all of these phases have previously been determined to exist in Hanford tank sludge. The leachate solution was sampled at selected time intervals and analyzed for the specific metal ion involved (Al, Bi, Ca, or Cr) and for P (total and as phosphate). The solids remaining after completion of the caustic leaching step were analyzed to determine the reaction product. In the second experiment, the dependence of P removal from bismuth phosphate was examined as a function of the hydroxide ion concentration. It was anticipated that a plot of log[phosphate] versus log[hydroxide] would provide insight into the phosphorus-removal mechanism. This report describes the test activities outlined in Section 6.3.2.1, Preliminary Investigation of Phosphate Dissolution, in Test Plan TP-RPP-WTP-467, Rev.1. The objectives, success criteria, and test conditions of Section 6.3.2.1 are summarized here.
Date: March 5, 2008
Creator: Lumetta, Gregg J.
Object Type: Report
System: The UNT Digital Library
Allinea DDT as a Parallel Debugging Alternative to Totalview (open access)

Allinea DDT as a Parallel Debugging Alternative to Totalview

Totalview, from the Etnus Corporation, is a sophisticated and feature rich software debugger for parallel applications. As Totalview has gained in popularity and market share its pricing model has increased to the point where it is often prohibitively expensive for massively parallel supercomputers. Additionally, many of Totalview's advanced features are not used by members of the scientific computing community. For these reasons, supercomputing centers have begun to search for a basic parallel debugging tool which can be used as an alternative to Totalview. As the cost and complexity of Totalview has increased over the years, scientific computing centers have started searching for a viable parallel debugging alternative. DDT (Distributed Debugging Tool) from Allinea Software is a relatively new parallel debugging tool which aims to provide much of the same functionality as Totalview. This review outlines the basic features and limitations of DDT to determine if it can be a reasonable substitute for Totalview. DDT was tested on the NERSC platforms Bassi, Seaborg, Jacquard and Davinci with Fortran90, C, and C++ codes using MPI and OpenMP for parallelism.
Date: March 5, 2007
Creator: Antypas, K.B.
Object Type: Report
System: The UNT Digital Library
OFFGAS GENERATION FROM THE DISPOSITION OF SCRAP PLUTONIUM BY VITRIFICATION SIMULANT TESTS (open access)

OFFGAS GENERATION FROM THE DISPOSITION OF SCRAP PLUTONIUM BY VITRIFICATION SIMULANT TESTS

The Department of Energy Office of Environmental Management is supporting R&D for the conceptual design of the Plutonium Disposition Project at the Savannah River Site in Aiken, SC to reduce the attractiveness of plutonium scrap by fabricating a durable plutonium oxide glass form and immobilizing this form within the high-level waste glass prepared in the Defense Waste Processing Facility. A glass formulation was developed that is capable of incorporating large amounts of actinides as well as accommodating many impurities that may be associated with impure Pu feed streams. The basis for the glass formulation was derived from commercial glasses that had high lanthanide loadings. A development effort led to a Lanthanide BoroSilicate (LaBS) glass that accommodated significant quantities of actinides, tolerated impurities associated with the actinide feed streams and could be processed using established melter technologies. A Cylindrical Induction Melter (CIM) was used for vitrification of the Pu LaBS glass. Induction melting for the immobilization of americium and curium (Am/Cm) in a glass matrix was first demonstrated in 1997. The induction melting system was developed to vitrify a non-radioactive Am/Cm simulant combined with a glass frit. Most of the development of the melter itself was completed as part of that …
Date: March 5, 2008
Creator: Zamecnik, J; Patricia Toole, P; David Best, D; Timothy Jones, T; Donald02 Miller, D; Whitney Thomas, W et al.
Object Type: Article
System: The UNT Digital Library
WIPP Facility Work Plan for Solid Waste Management Units and Areas of Concern (open access)

WIPP Facility Work Plan for Solid Waste Management Units and Areas of Concern

This 2002 Facility Work Plan (FWP) has been prepared as required by Module VII, Permit Condition VII.U.3 of the Waste Isolation Pilot Plant (WIPP) Hazardous Waste Facility Permit, NM4890139088-TSDF (the Permit) (New Mexico Environment Department [NMED], 1999a), and incorporates comments from the NMED received on December 6, 2000 (NMED, 2000a). This February 2002 FWP describes the programmatic facility-wide approach to future investigations at Solid Waste Management Units (SWMU) and Areas of Concern (AOC) specified in the Permit. The Permittees are evaluating data from previous investigations of the SWMUs and AOCs against the most recent guidance proposed by the NMED. Based on these data, and completion of the August 2001 sampling requested by the NMED, the Permittees expect that no further sampling will be required and that a request for No Further Action (NFA) at the SWMUs and AOCs will be submitted to the NMED. This FWP addresses the current Permit requirements. It uses the results of previous investigations performed at WIPP and expands the investigations as required by the Permit. As an alternative to the Resource Conservation and Recovery Act (RCRA) Facility Investigation (RFI) specified in Module VII of the Permit, current NMED guidance identifies an Accelerated Corrective Action Approach …
Date: March 5, 2002
Creator: Westinghouse TRU Solutions LLC
Object Type: Report
System: The UNT Digital Library
RCRA Assessment Plan for Single-Shell Tank Waste Management Area T at the Hanford Site, Interim Change Notice 1 (open access)

RCRA Assessment Plan for Single-Shell Tank Waste Management Area T at the Hanford Site, Interim Change Notice 1

This interim change notice updates the assessment plan to refelct the current wells in the monitoring system and the current constituent list for Waste Management Area T.
Date: March 5, 2002
Creator: Horton, Duane G.
Object Type: Report
System: The UNT Digital Library
The 1997/98 El Nino: A Test for Climate Models (open access)

The 1997/98 El Nino: A Test for Climate Models

Version 3 of the Hadley Centre Atmospheric Model (HadAM3) has been used to demonstrate one means of comparing a general circulation model with observations for a specific climate perturbation, namely the strong 1997/98 El Nino. This event was characterized by the collapse of the tropical Pacific's Walker circulation, caused by the lack of a zonal sea surface temperature gradient during the El Nino. Relative to normal years, cloud altitudes were lower in the western portion of the Pacific and higher in the eastern portion. HadAM3 likewise produced the observed collapse of the Walker circulation, and it did a reasonable job of reproducing the west/east cloud structure changes. This illustrates that the 1997/98 El Nino serves as a useful means of testing cloud-climate interactions in climate models.
Date: March 5, 2004
Creator: Lu, R; Dong, B; Cess, R D & Potter, G L
Object Type: Article
System: The UNT Digital Library
Feasibility Study of Passive Aerosol Sampler for Bio-Agent Detection (open access)

Feasibility Study of Passive Aerosol Sampler for Bio-Agent Detection

We propose to establish the feasibility of a passive aerosol sampler for bio-agent collection through laboratory experiments and theoretical analysis. The passive sampler, unlike the typical active sampler, does not require pumps and complex fixtures, and thereby allows for large-scale field monitoring not possible with current active samplers. We plan to conduct experiments using model (both biological and non-biological) aerosols generated in an instrumented test chamber and compare the particles collected on various passive samplers to conventional filter samplers, commercial aerosol measuring instruments and to conventional surface swipes. Theoretical analysis will be used to design prototype passive samplers and to compare experimental results with theory. A successful feasibility study will be used to seek outside funding for applications that will greatly enhance current LLNL programs such as NARAC's atmospheric dispersal modeling, NAI's programs in bioagent monitoring in public locations and fixed sampling stations, and EPD's environmental monitoring and decontamination research. In addition, the feasibility study will position us favorably for responding to new calls for proposals by NIH and EPA for large scale environmental studies.
Date: March 5, 2003
Creator: Keating, G. & Bergman, W.
Object Type: Report
System: The UNT Digital Library
Status of Optical Coatings for the National Ignition Facility (open access)

Status of Optical Coatings for the National Ignition Facility

Optical coatings are a crucial part of the pulse trapping and extraction in the NIF multipass amplifiers. Coatings also steer the 192 beams from four linear arrays to four converging cones entering the target chamber. There are a total of 1600 physical vapor deposited coatings on NIF consisting of 576 mirrors within the multipass cavity, 192 polarizers that work in tandem with a Pockels cell to create an optical switch, and 832 transport mirrors. These optics are of sufficient size so that they are not aperture-limiting for the 40-cm x 40 cm beams over an incident range of 0 to 56.4 degrees. These coatings must withstand laser fluences up to 25 J/cm{sup 2} at 1053 nm (1 {omega}) and 3-ns pulse length and are the 1{omega} fluence-limiting component on NIF. The coatings must have a minimal impact on the beam wavefront and phase to maintain beam focusability, minimize scattered loss, and minimize nonlinear damage mechanisms. This is achieved by specifications ranging from <50 MPa coating stress, <1% coating nonuniformity, <4{angstrom} RMS surface roughness, and a PSD specification to control the amplitude of periodic spatial frequencies. Finally, the primary mission of optical coatings is efficient beam steering so reflection and transmission …
Date: March 5, 2001
Creator: Stolz, C. J.; Weinzapfel, C.; Rogowski, G. T.; Smith, D.; Rigatti, A.; Oliver, J. et al.
Object Type: Article
System: The UNT Digital Library
Applying Loop Optimizations to Object-oriented Abstractions Through General Classification of Array Semantics (open access)

Applying Loop Optimizations to Object-oriented Abstractions Through General Classification of Array Semantics

Optimizing compilers have a long history of applying loop transformations to C and Fortran scientific applications. However, such optimizations are rare in compilers for object-oriented languages such as C++ or Java, where loops operating on user-defined types are left unoptimized due to their unknown semantics. Our goal is to reduce the performance penalty of using high-level object-oriented abstractions. We propose an approach that allows the explicit communication between programmers and compilers. We have extended the traditional Fortran loop optimizations with an open interface. Through this interface, we have developed techniques to automatically recognize and optimize user-defined array abstractions. In addition, we have developed an adapted constant-propagation algorithm to automatically propagate properties of abstractions. We have implemented these techniques in a C++ source-to-source translator and have applied them to optimize several kernels written using an array-class library. Our experimental results show that using our approach, applications using high-level abstractions can achieve comparable, and in cases superior, performance to that achieved by efficient low-level hand-written codes.
Date: March 5, 2004
Creator: Yi, Q & Quinlan, D
Object Type: Article
System: The UNT Digital Library
Estimated Entrainment of Dungeness Crab During Maintenance Dredging of the Mouth of the Columbia River, Summer 2002 (open access)

Estimated Entrainment of Dungeness Crab During Maintenance Dredging of the Mouth of the Columbia River, Summer 2002

To address concerns about crab entrainment during maintenance dredging at the Mouth of the Columbia River, direct measurements of crab entrainment rates were conducted during the summer of 2002 from River Mile 3 to River Mile+3. The entrainment rate for all age classes over all sampling in the MCR was 0.0603 crabs per cy. The sex ratio of the older crabs entrained in the MCR was significantly skewed to the females. A modified DIM was used to calculate the entrainment (E), Adult Equivalent Loss (AEL) at Age 2+ and Age 3+ and the Loss to the Fishery (LF) for the dredged volumes accomplished in 2002 and for the five-year average dredged volumes (both for the Essayons and the contractor dredges). For both sets of projections, the coefficients of variation on the E, AEL, and LF were all under 5%. For the MCR total dredged volume (4,600,378 cy) in the summer of 2002, the estimated AEL at age 2+ was 180,416 crabs with 95% confidence limits from 163,549 to 197,283 crabs. The AEL at age 3+ estimated for the summer 2002 in the MCR was 81,187 with 95% confidence limits from 73,597 to 88,777 crabs. The projected LF for summer 2002 …
Date: March 5, 2003
Creator: Pearson, Walter H.; Williams, Greg D. & Skalski, John R.
Object Type: Report
System: The UNT Digital Library
Assessment of Physical Properties of Transuranic Waste in Hanford Single-Shell Tanks (open access)

Assessment of Physical Properties of Transuranic Waste in Hanford Single-Shell Tanks

CH2M HILL Hanford Group, Inc. (CH2M HILL) is in the process of identifying and developing supplemental process technologies to accelerate the tank waste cleanup mission. One technology targets disposal of Hanford transuranic (TRU) process wastes stored in single-shell tanks (SSTs). Ten Hanford SSTs are candidates for designation as contact-handled TRU waste type: the B-200 series tanks (241-B-201, -B-202, -B-203, and -B-204), the T-200 series tanks (241-T-201, -T-202, -T-203, and -T-204), and Tanks 241-T-110 and T-111. Current plans identify a process in which these wastes are retrieved from the tanks, either dry or with a recycled liquid stream to help mobilize the waste in the tank and through transfer lines and vessels, dewatered to remove excess liquid, and transferred to waste packages in a form suitable for disposal. CH2M HILL seeks to procure a process for dewatering, handling, and packaging the contact-handled TRU waste after it is retrieved. An understanding of waste physical properties is needed to support design of the SST TRU handling and packaging system and to produce suitable physical simulants to test such a process. Pacific Northwest National Laboratory (PNNL) has been tasked with developing these waste simulants. This report summarizes PNNL's assessment of available waste physical property …
Date: March 5, 2003
Creator: Rassat, Scot D.; Mahoney, Lenna A.; Wells, Beric E.; Mendoza, Donaldo P. & Caldwell, Dustin D.
Object Type: Report
System: The UNT Digital Library
Reinvestigation of the Direct Two-proton Decay of the Long-lived Isomer 94Agm [0.4 s, 6.7 MeV, (21+)] (open access)

Reinvestigation of the Direct Two-proton Decay of the Long-lived Isomer 94Agm [0.4 s, 6.7 MeV, (21+)]

An attempt to confirm the reported direct one-proton and two-proton decays of the (21+) isomer at 6.7(5) MeV in 94Ag has been made. The 0.39(4) s half-life of the isomer permitted use of a helium-jet system to transport reaction products from the 40Ca + natNi reaction at 197 MeV to a low-background area; 24 gas Delta E-(Si) E detector telescopes were used to identify emitted protons down to 0.4 MeV. No evidence was obtained for two-proton radioactivity with a summed energy of 1.9(1) MeV and a branching ratio of 0.5(3)percent. Two groups of one-proton radioactivity from this isomer had also been reported; our data confirm the lower energy group at 0.79(3) MeV with its branching ratio of 1.9(5)percent.
Date: March 5, 2009
Creator: Cerny, J.; Moltz, D. M.; Lee, D. W.; Perajarvi, K.; Barquest, B. R.; Grossman, L. E. et al.
Object Type: Article
System: The UNT Digital Library
Cloud Scavenging Effects on Aerosol Radiative and Cloud-nucleating Properties - Final Technical Report (open access)

Cloud Scavenging Effects on Aerosol Radiative and Cloud-nucleating Properties - Final Technical Report

The optical properties of aerosol particles are the controlling factors in determining direct aerosol radiative forcing. These optical properties depend on the chemical composition and size distribution of the aerosol particles, which can change due to various processes during the particles’ lifetime in the atmosphere. Over the course of this project we have studied how cloud processing of atmospheric aerosol changes the aerosol optical properties. A counterflow virtual impactor was used to separate cloud drops from interstitial aerosol and parallel aerosol systems were used to measure the optical properties of the interstitial and cloud-scavenged aerosol. Specifically, aerosol light scattering, back-scattering and absorption were measured and used to derive radiatively significant parameters such as aerosol single scattering albedo and backscatter fraction for cloud-scavenged and interstitial aerosol. This data allows us to demonstrate that the radiative properties of cloud-processed aerosol can be quite different than pre-cloud aerosol. These differences can be used to improve the parameterization of aerosol forcing in climate models.
Date: March 5, 2009
Creator: Ogren, John A.; Sheridan, Patrick S. & Andrews, Elisabeth
Object Type: Report
System: The UNT Digital Library
Assessing the Effect of Timing of Availability for Carbon Dioxide Storage in the Largest Oil and Gas Pools in the Alberta Basin: Description of Data and Methodology (open access)

Assessing the Effect of Timing of Availability for Carbon Dioxide Storage in the Largest Oil and Gas Pools in the Alberta Basin: Description of Data and Methodology

Carbon dioxide capture from large stationary sources and storage in geological media is a technologically-feasible mitigation measure for the reduction of anthropogenic emissions of CO2 to the atmosphere in response to climate change. Carbon dioxide (CO2) can be sequestered underground in oil and gas reservoirs, in deep saline aquifers, in uneconomic coal beds and in salt caverns. The Alberta Basin provides a very large capacity for CO2 storage in oil and gas reservoirs, along with significant capacity in deep saline formations and possible unmineable coal beds. Regional assessments of potential geological CO2 storage capacity have largely focused so far on estimating the total capacity that might be available within each type of reservoir. While deep saline formations are effectively able to accept CO2 immediately, the storage potential of other classes of candidate storage reservoirs, primarily oil and gas fields, is not fully available at present time. Capacity estimates to date have largely overlooked rates of depletion in these types of storage reservoirs and typically report the total estimated storage capacity that will be available upon depletion. However, CO2 storage will not (and cannot economically) begin until the recoverable oil and gas have been produced via traditional means. This report describes …
Date: March 5, 2007
Creator: Dahowski, Robert T. & Bachu, Stefan
Object Type: Report
System: The UNT Digital Library
The Confinement Problem in Lattice Gauge Theory (open access)

The Confinement Problem in Lattice Gauge Theory

I review investigations of the quark confinement mechanism that have been carried out in the framework of SU(N) lattice gauge theory. The special role of Z(N) center symmetry is emphasized.
Date: March 5, 2003
Creator: Greensite, J.
Object Type: Article
System: The UNT Digital Library
Laboratory Investigations of a Low-Swirl Injector with H2 and CH4 at Gas Turbine Conditions (open access)

Laboratory Investigations of a Low-Swirl Injector with H2 and CH4 at Gas Turbine Conditions

Laboratory experiments were conducted at gas turbine and atmospheric conditions (0.101 < P{sub 0} < 0.810 MPa, 298 < T{sub 0} < 580K, 18 < U{sub 0} < 60 m/s) to characterize the overall behaviors and emissions of the turbulent premixed flames produced by a low-swirl injector (LSI) for gas turbines. The objective was to investigate the effects of hydrogen on the combustion processes for the adaptation to gas turbines in an IGCC power plant. The experiments at high pressures and temperatures showed that the LSI can operate with 100% H{sub 2} at up to {phi} = 0.5 and has a slightly higher flashback tolerance than an idealized high-swirl design. With increasing H{sub 2} fuel concentration, the lifted LSI flame begins to shift closer to the exit and eventually attaches to the nozzle rim and assumes a different shape at 100% H{sub 2}. The STP experiments show the same phenomena. The analysis of velocity data from PIV shows that the stabilization mechanism of the LSI remains unchanged up to 60% H{sub 2}. The change in the flame position with increasing H{sub 2} concentration is attributed to the increase in the turbulent flame speed. The NO{sub x} emissions show a log …
Date: March 5, 2008
Creator: Cheng, R. K.; Littlejohn, D.; Strakey, P.A. & Sidwell, T.
Object Type: Article
System: The UNT Digital Library
Solid Oxide Fuel Cell Technology Stationary Power Application Project (open access)

Solid Oxide Fuel Cell Technology Stationary Power Application Project

The objectives of this program were to: (1) Develop a reliable, cost-effective, and production-friendly technique to apply the power-enhancing layer at the interface of the air electrode and electrolyte of the Siemens SOFC; (2) Design, build, install, and operate in the field two 5 kWe SOFC systems fabricated with the state-of-the-art cylindrical, tubular cell and bundle technology and incorporating advanced module design features. Siemens successfully demonstrated, first in a number of single cell tests and subsequently in a 48-cell bundle test, a significant power enhancement by employing a power-enhancing composite interlayer at the interface between the air electrode and electrolyte. While successful from a cell power enhancement perspective, the interlayer application process was not suitable for mass manufacturing. The application process was of inconsistent quality, labor intensive, and did not have an acceptable yield. This program evaluated the technical feasibility of four interlayer application techniques. The candidate techniques were selected based on their potential to achieve the technical requirements of the interlayer, to minimize costs (both labor and material), and suitably for large-scale manufacturing. Preliminary screening, utilizing lessons learned in manufacturing tubular cells, narrowed the candidate processes to two, ink-roller coating (IRC) and dip coating (DC). Prototype fixtures were successfully …
Date: March 5, 2009
Creator: Pierre, Joseph
Object Type: Report
System: The UNT Digital Library
Design, Installation and Performance of the New insulator for NSTX CHI Experiments (open access)

Design, Installation and Performance of the New insulator for NSTX CHI Experiments

Coaxial Helicity Injection (CHI), a non-inductive method to initiate plasma and generate toroidal plasma current, is being investigated in the National Spherical Torus Experiment (NSTX). The center stack and outer vacuum vessel are separated by insulating gaps at the top and bottom of the slim central column so that a high voltage (up to 2 kV) can be applied between them from a pulsed power supply or a capacitor bank to initiate an arc discharge. In the presence of a suitable poloidal magnetic field, the discharge is initiated at the lower gap (the injector gap) and because of the strong toroidal field develops a helical structure resulting in substantial toroidal plasma current being driven. In NSTX, up to 390 kA of toroidal current has been generated for an injected current of 25 kA. The early investigations of CHI however frequently developed arcs across the insulator at the top of the machine (the absorber gap), which terminated the desired discharge. This arcing greatly restricted the operational space available for CHI studies. During 2002, the absorber region was modified to suppress these arcs. The new design includes a new ceramic insulator on the high field side of the absorber region with a …
Date: March 5, 2008
Creator: Mueller, D.; Chrzanowski, J.; Gates, D.; Menard, J.; Raman, R.; Jarboe, T. R. et al.
Object Type: Article
System: The UNT Digital Library
APPLICATION OF STIR BAR SORPTIVE EXTRACTION TO ANALYSIS OF VOLATILE AND SEMIVOLATILE ORGANIC CHEMICALS OF POTENTIAL CONCERN IN SOLIDS AND AQUEOUS SAMPLES FROM THE HANFORD SITE (open access)

APPLICATION OF STIR BAR SORPTIVE EXTRACTION TO ANALYSIS OF VOLATILE AND SEMIVOLATILE ORGANIC CHEMICALS OF POTENTIAL CONCERN IN SOLIDS AND AQUEOUS SAMPLES FROM THE HANFORD SITE

Stir bar sorptive extraction was applied to aqueous and solid samples for the extraction and analysis of organic compounds from the Hanford chemicals of potential concern list, as identified in the vapor data quality objectives. The 222-S Laboratory analyzed these compounds from vapor samples on thermal desorption tubes as part of the Hanford Site industrial hygiene vapor sampling effort.
Date: March 5, 2009
Creator: JM, FRYE & JM, KUNKEL
Object Type: Report
System: The UNT Digital Library
Mechanisms of High Temperature/Low Stress Creep of Ni-Based Superalloy Single Crystals (open access)

Mechanisms of High Temperature/Low Stress Creep of Ni-Based Superalloy Single Crystals

Cast nickel-based superalloys are used for blades in land-based, energy conversion and powerplant applications, as well as in aircraft gas turbines operating at temperatures up to 1100 C, where creep is one of the life-limiting factors. Creep of superalloy single crystals has been extensively studied over the last several decades. Surprisingly, only recently has work focused specifically on the dislocation mechanisms that govern high temperature and low stress creep. Nevertheless, the perpetual goal of better engine efficiency demands that the creep mechanisms operative in this regime be fully understood in order to develop alloys and microstructures with improved high temperature capability. At present, the micro-mechanisms controlling creep before and after rafting (the microstructure evolution typical of high temperature creep) has occurred have yet to be identified and modeled, particularly for [001] oriented single crystals. This crystal orientation is most interesting technologically since it exhibits the highest creep strength. The major goal of the program entitled ''Mechanisms of High Temperature/Low Stress Creep of Ni-Based Superalloy Single Crystals'' (DOE Grant DE-FG02-04ER46137) has been to elucidate these creep mechanisms in cast nickel-based superalloys. We have utilized a combination of detailed microstructure and dislocation substructure analysis combined with the development of a novel phase-field …
Date: March 5, 2009
Creator: Mills, Michael J.
Object Type: Report
System: The UNT Digital Library
Theory Challenges of the Accelerating Universe (open access)

Theory Challenges of the Accelerating Universe

The accelerating expansion of the universe presents an exciting, fundamental challenge to the standard models of particle physics and cosmology. I highlight some of the outstanding challenges in both developing theoretical models and interpreting without bias the observational results from precision cosmology experiments in the next decade that will return data to help reveal the nature of the new physics. Examples given focus on distinguishing a new component of energy from a new law of gravity, and the effect of early dark energy on baryon acoustic oscillations.
Date: March 5, 2007
Creator: Linder, Eric V.
Object Type: Article
System: The UNT Digital Library
The KamLAND Full-Volume Calibration System (open access)

The KamLAND Full-Volume Calibration System

We have successfully built and operated a source deployment system for the KamLAND detector. This system was used to position radioactive sources throughout the delicate 1-kton liquid scintillator volume, while meeting stringent material cleanliness, material compatibility, and safety requirements. The calibration data obtained with this device were used to fully characterize detector position and energy reconstruction biases. As a result, the uncertainty in the size of the detector fiducial volume was reduced by a factor of two. Prior to calibration with this system, the fiducial volume was the largest source of systematic uncertainty in measuring the number of antineutrinos detected by KamLAND. This paper describes the design, operation and performance of this unique calibration system.
Date: March 5, 2009
Creator: Collaboration, KamLAND; Berger, B. E.; Busenitz, J.; Classen, T.; Decowski, M. P.; Dwyer, D. A. et al.
Object Type: Article
System: The UNT Digital Library