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Technology Overview: Concentrator PV 2010 Boot Camp (CPV)

The presentation introduces the various types of CPV technologies and provides a status report of today's CPV companies. Six different architectures of multijunction cells are shown to near or surpass 40% in efficiency. The design space for CPV is quite complex, which is a curse for those trying to narrow it down for the first prototype, but a blessing for those who want multiple pathways for product improvement in coming years.
Date: October 11, 2010
Creator: Kurtz, S.; Bett, A. & Hartsoch, N.
Object Type: Presentation
System: The UNT Digital Library
Storage Viability and Optimization Web Service (open access)

Storage Viability and Optimization Web Service

Non-residential sectors offer many promising applications for electrical storage (batteries) and photovoltaics (PVs). However, choosing and operating storage under complex tariff structures poses a daunting technical and economic problem that may discourage potential customers and result in lost carbon and economic savings. Equipment vendors are unlikely to provide adequate environmental analysis or unbiased economic results to potential clients, and are even less likely to completely describe the robustness of choices in the face of changing fuel prices and tariffs. Given these considerations, researchers at Lawrence Berkeley National Laboratory (LBNL) have designed the Storage Viability and Optimization Web Service (SVOW): a tool that helps building owners, operators and managers to decide if storage technologies and PVs merit deeper analysis. SVOW is an open access, web-based energy storage and PV analysis calculator, accessible by secure remote login. Upon first login, the user sees an overview of the parameters: load profile, tariff, technologies, and solar radiation location. Each parameter has a pull-down list of possible predefined inputs and users may upload their own as necessary. Since the non-residential sectors encompass a broad range of facilities with fundamentally different characteristics, the tool starts by asking the users to select a load profile from a …
Date: October 11, 2010
Creator: Stadler, Michael; Marnay, Christ; Lai, Judy; Siddiqui, Afzal; Limpaitoon, Tanachai; Phan, Trucy et al.
Object Type: Report
System: The UNT Digital Library
Analysis of Failed and Nickel-coated 3093 Beam Clamp Components at the East Tennessee Technology Park (ettp) (open access)

Analysis of Failed and Nickel-coated 3093 Beam Clamp Components at the East Tennessee Technology Park (ettp)

The U.S. Department of Energy and its contractor, Bechtel Jacobs Company (BJC), are undertaking a major effort to clean up the former gaseous diffusion facility (K-25) located in Oak Ridge, TN. The decontamination and decommissioning activities require systematic removal of contaminated equipment and machinery followed by demolition of the buildings. As part of the cleanup activities, a beam clamp, used for horizontal life lines (HLLs) for fall protection, was discovered to be fractured during routine inspection. The beam clamp (yoke and D-ring) was a component in the HLL system purchased from Reliance Industries LLC. Specifically, the U-shaped stainless steel yoke of the beam clamp failed in a brittle mode at under less than 10% of the rated design capacity of 14,500 lb. The beam clamp had been in service for approximately 16 months. Bechtel Jacobs approached Argonne National Laboratory to assist in identifying the root cause of the failure of the beam clamp. The objectives of this study were to (1) review the prior reports and documents on the subject, (2) understand the possible failure mechanism(s) that resulted in the failed beam clamp components, (3) recommend approaches to mitigate the failure mechanism(s), and (4) evaluate the modified beam clamp assemblies. …
Date: October 11, 2010
Creator: Singh, D.; Pappacena, K.; Gaviria, J.; Burtsteva, T. & Division, Nuclear Engineering
Object Type: Report
System: The UNT Digital Library
Lake Granbury and Lake Whitney Assessment Initiative Final Scientific/Technical Report Summary (open access)

Lake Granbury and Lake Whitney Assessment Initiative Final Scientific/Technical Report Summary

A team of Texas AgriLife Research, Baylor University and University of Texas at Arlington researchers studied the biology and ecology of Prymnesium parvum (golden algae) in Texas lakes using a three-fold approach that involved system-wide monitoring, experimentation at the microcosm and mesocosm scales, and mathematical modeling. The following are conclusions, to date, regarding this organism’s ecology and potential strategies for mitigation of blooms by this organism. In-lake monitoring revealed that golden algae are present throughout the year, even in lakes where blooms do not occur. Compilation of our field monitoring data with data collected by Texas Parks and Wildlife and Brazos River Authority (a period spanning a decade) revealed that inflow and salinity variables affect bloom formations. Thresholds for algae populations vary per lake, likely due to adaptations to local conditions, and also to variations in lake-basin morphometry, especially the presence of coves that may serve as hydraulic storage zones for P. parvum populations. More specifically, our in-lake monitoring showed that the highly toxic bloom that occurred in Lake Granbury in the winter of 2006/2007 was eliminated by increased river inflow events. The bloom was flushed from the system. The lower salinities that resulted contributed to golden algae not blooming …
Date: October 11, 2010
Creator: Harris, B.L.; Roelke, Daniel; Brooks, Bryan & Grover, James
Object Type: Report
System: The UNT Digital Library
Life-Cycle Analysis Results of Geothermal Systems in Comparison to Other Power Systems. (open access)

Life-Cycle Analysis Results of Geothermal Systems in Comparison to Other Power Systems.

A life-cycle energy and greenhouse gas emissions analysis has been conducted with Argonne National Laboratory's expanded Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model for geothermal power-generating technologies, including enhanced geothermal, hydrothermal flash, and hydrothermal binary technologies. As a basis of comparison, a similar analysis has been conducted for other power-generating systems, including coal, natural gas combined cycle, nuclear, hydroelectric, wind, photovoltaic, and biomass by expanding the GREET model to include power plant construction for these latter systems with literature data. In this way, the GREET model has been expanded to include plant construction, as well as the usual fuel production and consumption stages of power plant life cycles. For the plant construction phase, on a per-megawatt (MW) output basis, conventional power plants in general are found to require less steel and concrete than renewable power systems. With the exception of the concrete requirements for gravity dam hydroelectric, enhanced geothermal and hydrothermal binary used more of these materials per MW than other renewable power-generation systems. Energy and greenhouse gas (GHG) ratios for the infrastructure and other life-cycle stages have also been developed in this study per kilowatt-hour (kWh) of electricity output by taking into account both plant …
Date: October 11, 2010
Creator: Sullivan, J. L.; Clark, C. E.; Han, J.; Wang, M. & Systems, Energy
Object Type: Report
System: The UNT Digital Library
A Simple Apparatus for the Injection of Lithium Aerosol into the Scrape-Off Layer of Fusion Research Devices (open access)

A Simple Apparatus for the Injection of Lithium Aerosol into the Scrape-Off Layer of Fusion Research Devices

A simple device has been developed to deposit elemental lithium onto plasma facing components in the National Spherical Torus Experiment. Deposition is accomplished by dropping lithium powder into the plasma column. Once introduced, lithium particles quickly become entrained in scrape-off layer flow as an evaporating aerosol. Particles are delivered through a small central aperture in a computer-controlled resonating piezoelectric disk on which the powder is supported. The device has been used to deposit lithium both during discharges as well as prior to plasma breakdown. Clear improvements to plasma performance have been demonstrated. The use of this apparatus provides flexibility in the amount and timing of lithium deposition and, therefore, may benefit future fusion research devices.
Date: October 11, 2010
Creator: D. K. Mansfield, A.L Roquemore, H. Schneider, J. Timberlake, H. Kugel, M.G. Bell and the NSTX Research Team
Object Type: Report
System: The UNT Digital Library
YALINA-booster Subcritical Assembly Pulsed-Neutron Experiments : Data Processing and Spatial Corrections. (open access)

YALINA-booster Subcritical Assembly Pulsed-Neutron Experiments : Data Processing and Spatial Corrections.

The YALINA-Booster experiments and analyses are part of the collaboration between Argonne National Laboratory of USA and the Joint Institute for Power & Nuclear Research - SOSNY of Belarus for studying the physics of accelerator driven systems for nuclear energy applications using low enriched uranium. The YALINA-Booster subcritical assembly is utilized for studying the kinetics of accelerator driven systems with its highly intensive D-T or D-D pulsed neutron source. In particular, the pulsed neutron methods are used to determine the reactivity of the subcritical system. This report examines the pulsed-neutron experiments performed in the YALINA-Booster facility with different configurations for the subcritical assembly. The 1141 configuration with 90% U-235 fuel and the 1185 configuration with 36% or 21% U-235 fuel are examined. The Sjoestrand area-ratio method is utilized to determine the reactivities of the different configurations. The linear regression method is applied to obtain the prompt neutron decay constants from the pulsed-neutron experimental data. The reactivity values obtained from the experimental data are shown to be dependent on the detector locations inside the subcritical assembly and the types of detector used for the measurements. In this report, Bell's spatial correction factors are calculated based on a Monte Carlo model to …
Date: October 11, 2010
Creator: Cao, Y.; Gohar, Y. & Division, Nuclear Engineering
Object Type: Report
System: The UNT Digital Library
YALINA-booster Subcritical Assembly Pulsed-Neutron E Xperiments: Detector Dead Time and Apatial Corrections. (open access)

YALINA-booster Subcritical Assembly Pulsed-Neutron E Xperiments: Detector Dead Time and Apatial Corrections.

In almost every detector counting system, a minimal dead time is required to record two successive events as two separated pulses. Due to the random nature of neutron interactions in the subcritical assembly, there is always some probability that a true neutron event will not be recorded because it occurs too close to the preceding event. These losses may become rather severe for counting systems with high counting rates, and should be corrected before any utilization of the experimental data. This report examines the dead time effects for the pulsed neutron experiments of the YALINA-Booster subcritical assembly. The nonparalyzable model is utilized to correct the experimental data due to dead time. Overall, the reactivity values are increased by 0.19$ and 0.32$ after the spatial corrections for the YALINA-Booster 36% and 21% configurations respectively. The differences of the reactivities obtained with He-3 long or short detectors at the same detector channel diminish after the dead time corrections of the experimental data for the 36% YALINA-Booster configuration. In addition, better agreements between reactivities obtained from different experimental data sets are also observed after the dead time corrections for the 21% YALINA-Booster configuration.
Date: October 11, 2010
Creator: Cao, Y.; Gohar, Y. & Division, Nuclear Engineering
Object Type: Report
System: The UNT Digital Library
Sweetwater Reporter (Sweetwater, Tex.), Vol. 112, No. 279, Ed. 1 Monday, October 11, 2010 (open access)

Sweetwater Reporter (Sweetwater, Tex.), Vol. 112, No. 279, Ed. 1 Monday, October 11, 2010

Daily newspaper from Sweetwater, Texas that includes local, state, and national news along with advertising.
Date: October 11, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
A Permanent-Magnet Microwave Ion Source for a Compact High-Yield Neutron Generator (open access)

A Permanent-Magnet Microwave Ion Source for a Compact High-Yield Neutron Generator

We present recent work on the development of a microwave ion source that will be used in a high-yield compact neutron generator for active interrogation applications. The sealed tube generator will be capable of producing high neutron yields, 5x1011 n/s for D-T and ~;;1x1010 n/s for D-D reactions, while remaining transportable. We constructed a microwave ion source (2.45 GHz) with permanent magnets to provide the magnetic field strength of 87.5 mT necessary for satisfying the electron cyclotron resonance (ECR) condition. Microwave ion sources can produce high extracted beam currents at the low gas pressures required for sealed tube operation and at lower power levels than previously used RF-driven ion sources. A 100 mA deuterium/tritium beam will be extracted through a large slit (60x6 mm2) to spread the beam power over a larger target area. This paper describes the design of the permanent-magnet microwave ion source and discusses the impact of the magnetic field design on the source performance. The required equivalent proton beam current density of 40 mA/cm2 was extracted at a moderate microwave power of 400 W with an optimized magnetic field.
Date: October 11, 2010
Creator: Waldmann, Ole & Ludewigt, Bernhard
Object Type: Article
System: The UNT Digital Library
Investigation of anti-Relaxation coatings for alkali-metal vapor cells using surface science techniques (open access)

Investigation of anti-Relaxation coatings for alkali-metal vapor cells using surface science techniques

Many technologies based on cells containing alkali-metal atomic vapor benefit from the use of antirelaxation surface coatings in order to preserve atomic spin polarization. In particular, paraffin has been used for this purpose for several decades and has been demonstrated to allow an atom to experience up to 10?000 collisions with the walls of its container without depolarizing, but the details of its operation remain poorly understood. We apply modern surface and bulk techniques to the study of paraffin coatings in order to characterize the properties that enable the effective preservation of alkali spin polarization. These methods include Fourier transform infrared spectroscopy, differential scanning calorimetry, atomic force microscopy, near-edge x-ray absorption fine structure spectroscopy, and x-ray photoelectron spectroscopy. We also compare the light-induced atomic desorption yields of several different paraffin materials. Experimental results include the determination that crystallinity of the coating material is unnecessary, and the detection of C=C double bonds present within a particular class of effective paraffin coatings. Further study should lead to the development of more robust paraffin antirelaxation coatings, as well as the design and synthesis of new classes of coating materials.
Date: October 11, 2010
Creator: Seltzer, S. J.; Michalak, D. J.; Donaldson, M. H.; Balabas, M. V.; Barber, S. K.; Bernasek, S. L. et al.
Object Type: Article
System: The UNT Digital Library

Collaborative Digital Repository Opportunities

This presentation discusses collaborative digital repository opportunities. The presentation offers questions and considerations as well as managing digital collections.
Date: October 11, 2010
Creator: Phillips, Mark Edward
Object Type: Presentation
System: The UNT Digital Library

Doctoral Recital: 2010-10-11 - Tzu-Ying Chan, violin

Recital presented at the UNT College of Music Recital Hall in partial fulfillment of the Doctor of Musical Arts (DMA) degree.
Date: October 11, 2010
Creator: Chan, Tzu-Ying
Object Type: Sound
System: The UNT Digital Library
The Oklahoma Daily (Norman, Okla.), Vol. 96, No. 37, Ed. 1 Monday, October 11, 2010 (open access)

The Oklahoma Daily (Norman, Okla.), Vol. 96, No. 37, Ed. 1 Monday, October 11, 2010

Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date: October 11, 2010
Creator: Moriak, Meredith
Object Type: Newspaper
System: The Gateway to Oklahoma History
Doctoral Lecture Recital: 2010-10-11 – Rachel Yoder, clarinet transcript

Doctoral Lecture Recital: 2010-10-11 – Rachel Yoder, clarinet

Recital presented at the UNT College of Music Merrill Ellis Intermedia Theater in partial fulfillment of the Doctor of Musical Arts(DMA)degree.
Date: October 11, 2010
Creator: Yoder, Rachel
Object Type: Sound
System: The UNT Digital Library