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2005 DOE Hydrogen Program Review PresentationCOST AND PERFORMANCE ENHANCEMENTS FOR A PEM FUEL CELL TURBOCOMPRESSOR (open access)

2005 DOE Hydrogen Program Review PresentationCOST AND PERFORMANCE ENHANCEMENTS FOR A PEM FUEL CELL TURBOCOMPRESSOR

The objectives of the program during the past year was to complete Technical Objectives 2 and 3 and initiate Technical Objective 4 are described. To assist the Department of Energy in the development of a low cost, reliable and high performance air compressor/expander. Technical Objective 1: Perform a turbocompressor systems PEM fuel cell trade study to determine the enhanced turbocompressor approach. Technical Objective 2: Using the results from technical objective 1, an enhanced turbocompressor will be fabricated. The design may be modified to match the flow requirements of a selected fuel cell system developer. Technical Objective 3: Design a cost and performance enhanced compact motor and motor controller. Technical Objective 4: Turbocompressor/motor controller development.
Date: April 1, 2005
Creator: Gee, Mark K.
System: The UNT Digital Library
About NICADD extruded scintillating strips (open access)

About NICADD extruded scintillating strips

The results of control measurements of extruded scintillating strip responses to a radioactive source Sr-90 are provided, and details of strip choice, preparation, and method of measurement are included. About four hundred one meter long extruded scintillating strips were measured at four different points. These results were essential for prototyping a tail catcher and muon tracker for a future international electron positron linear collider detector.
Date: April 1, 2005
Creator: Dyshkant, A.; Beznosko, D.; Blazey, G.; Chakraborty, D.; Francis, K.; Kubik, D. et al.
System: The UNT Digital Library
Abundance of Green Tree Frogs and Insects in Artificial Canopy Gaps in a Bottomland Hardwood Forest. (open access)

Abundance of Green Tree Frogs and Insects in Artificial Canopy Gaps in a Bottomland Hardwood Forest.

ABSTRACT - We found more green tree frogs ( Hyla cinerea) n canopv gaps than in closed canopy forest. Of the 331 green tree frogs observed, 88% were in canopv gaps. Likewise, higher numbers and biomasses of insects were captured in the open gap habitat Flies were the most commonlv collected insect group accounting for 54% of the total capture. These data suggest that one reason green tree frogs were more abundant in canopy gaps was the increased availability of prey and that small canopy gaps provide early successional habitats that are beneficial to green tree frog populations.
Date: April 1, 2005
Creator: Horn, Scott; Hanula, James, L.; Ulyshen, Michael D. & Kilgo, John, C.
System: The UNT Digital Library
Advanced Test Reactor Testing Experience: Past, Present and Future (open access)

Advanced Test Reactor Testing Experience: Past, Present and Future

The Advanced Test Reactor (ATR), at the Idaho National Laboratory (INL), is one of the world’s premier test reactors for providing the capability for studying the effects of intense neutron and gamma radiation on reactor materials and fuels. The physical configuration of the ATR, a 4-leaf clover shape, allows the reactor to be operated at different power levels in the corner “lobes” to allow for different testing conditions for multiple simultaneous experiments. The combination of high flux (maximum thermal neutron fluxes of 1E15 neutrons per square centimeter per second and maximum fast [E>1.0 MeV] neutron fluxes of 5E14 neutrons per square centimeter per second) and large test volumes (up to 48" long and 5.0" diameter) provide unique testing opportunities. The current experiments in the ATR are for a variety of test sponsors -- US government, foreign governments, private researchers, and commercial companies needing neutron irradiation services. There are three basic types of test configurations in the ATR. The simplest configuration is the sealed static capsule, wherein the target material is placed in a capsule, or plate form, and the capsule is in direct contact with the primary coolant. The next level of complexity of an experiment is an instrumented lead …
Date: April 1, 2005
Creator: Marshall, Frances M.
System: The UNT Digital Library
Analysis of the Hydrogen Infrastructure Needed to Enable Commercial Introduction of Hydrogen-Fueled Vehicles (open access)

Analysis of the Hydrogen Infrastructure Needed to Enable Commercial Introduction of Hydrogen-Fueled Vehicles

None
Date: April 1, 2005
Creator: Melendez, M.
System: The UNT Digital Library
Application of a Java-based, univel geometry, neutral particle Monte Carlo code to the searchlight problem (open access)

Application of a Java-based, univel geometry, neutral particle Monte Carlo code to the searchlight problem

A univel geometry, neutral particle Monte Carlo transport code, written entirely in the Java programming language, is under development for medical radiotherapy applications. The code uses ENDF-VI based continuous energy cross section data in a flexible XML format. Full neutron-photon coupling, including detailed photon production and photonuclear reactions, is included. Charged particle equilibrium is assumed within the patient model so that detailed transport of electrons produced by photon interactions may be neglected. External beam and internal distributed source descriptions for mixed neutron-photon sources are allowed. Flux and dose tallies are performed on a univel basis. A four-tap, shift-register-sequence random number generator is used. Initial verification and validation testing of the basic neutron transport routines is underway. The searchlight problem was chosen as a suitable first application because of the simplicity of the physical model. Results show excellent agreement with analytic solutions. Computation times for similar numbers of histories are comparable to other neutron MC codes written in C and FORTRAN.
Date: April 1, 2005
Creator: Wemple, Charles A. & Cogliati, Joshua J.
System: The UNT Digital Library
Automated Demand Response and Commissioning (open access)

Automated Demand Response and Commissioning

This paper describes the results from the second season of research to develop and evaluate the performance of new Automated Demand Response (Auto-DR) hardware and software technology in large facilities. Demand Response (DR) is a set of activities to reduce or shift electricity use to improve the electric grid reliability and manage electricity costs. Fully-Automated Demand Response does not involve human intervention, but is initiated at a home, building, or facility through receipt of an external communications signal. We refer to this as Auto-DR. The evaluation of the control and communications must be properly configured and pass through a set of test stages: Readiness, Approval, Price Client/Price Server Communication, Internet Gateway/Internet Relay Communication, Control of Equipment, and DR Shed Effectiveness. New commissioning tests are needed for such systems to improve connecting demand responsive building systems to the electric grid demand response systems.
Date: April 1, 2005
Creator: Piette, Mary Ann; Watson, David S.; Motegi, Naoya & Bourassa, Norman
System: The UNT Digital Library
Background reduction in cryogenic detectors (open access)

Background reduction in cryogenic detectors

This paper discusses the background reduction and rejection strategy of the Cryogenic Dark Matter Search (CDMS) experiment. Recent measurements of background levels from CDMS II at Soudan are presented, along with estimates for future improvements in sensitivity expected for a proposed SuperCDMS experiment at SNOLAB.
Date: April 1, 2005
Creator: Bauer, Daniel A.
System: The UNT Digital Library
BEopt: Software for Identifying Optimal Building Designs on the Path to Zero Net Energy; Preprint (open access)

BEopt: Software for Identifying Optimal Building Designs on the Path to Zero Net Energy; Preprint

A zero net energy (ZNE) building produces as much energy on-site as it uses on an annual basis--using a grid-tied, net-metered photovoltaic (PV) system and active solar. The optimal path to ZNE extends from a base case to the ZNE building through a series of energy-saving building designs with minimal energy-related owning and operating costs. BEopt is a computer program designed to find optimal building designs along the path to ZNE. A user selects from among predefined options in various categories to specify options to be considered in the optimization. Energy savings are calculated relative to a reference. The reference can be either a user-defined base-case building or a climate-specific Building America Benchmark building automatically generated by BEopt. The user can also review and modify detailed information on all available options and the Building America Benchmark in a linked options library spreadsheet.
Date: April 1, 2005
Creator: Christensen, C.; Horowitz, S.; Givler, T.; Courtney, A. & Barker, G.
System: The UNT Digital Library
Branching fractions and CP asymmetries in B ---> H+ Hh'- (open access)

Branching fractions and CP asymmetries in B ---> H+ Hh'-

Relative branching fractions of B{sub d,s} {yields} h{sup +}h'{sup -} decays (where h, h' = K or {pi}) and direct CP asymmetry in B{sub d} {yields} K{sup +}{pi}{sup -} have been measured with 180 pb{sup -1} of data collected by the CDFII detector at the Tevatron collider. This includes the first BR measurement of a charmless B{sub s} {yields} PP decay (B{sub s} {yields} K{sup +}K{sup -}).
Date: April 1, 2005
Creator: Punzi, Giovanni & /Pisa, Scuola Normale Superiore /INFN, Pisa
System: The UNT Digital Library
Combination of CDF and D0 limits on a gauge mediated SUSY model using diphoton and missing transverse energy channel (open access)

Combination of CDF and D0 limits on a gauge mediated SUSY model using diphoton and missing transverse energy channel

We combine the results of the CDF and D0 searches for chargino and neutralino production in Gauge-Mediated SUSY using the two-photon and missing E{sub T} channel. The data are p{bar p} collisions produced at the Tevatron with {radical}s = 1.96 TeV, with 202 pb{sup -1} collected at CDF and 263 pb{sup -1} collected at D0. The combined limit excludes a chargino mass less than 209 GeV/c{sup 2}. This result significantly extends the individual experimental limits.
Date: April 1, 2005
Creator: Buescher, V.; Culbertson, R.; Conway, J.; Gershtein, Y.; Grivaz, J-F.; Heinemann, B. et al.
System: The UNT Digital Library
Comparison of the complete genome sequences of Pseudomonassyringae pv. syringae B728a and pv. tomato DC3000. (open access)

Comparison of the complete genome sequences of Pseudomonassyringae pv. syringae B728a and pv. tomato DC3000.

The complete genomic sequence of Pseudomonas syringaepathovar syringae B728a (Pss B728a), has been determined and is comparedwith that of Pseudomonas syringae pv. tomato DC3000 (Pst DC3000). Thesetwo pathovars of this economically important species of plant pathogenicbacteria differ in host range and apparent patterns of interaction withplants, with Pss having a more pronounced epiphytic stage of growth andhigher abiotic stress tolerance and Pst DC3000 having a more pronouncedapoplastic growth habitat. The Pss B728a genome (6.1 megabases) containsa circular chromosome and no plasmid, whereas the Pst DC3000 genome is6.5 mbp in size, composed of a circular chromosome and two plasmids.While a high degree of similarity exists between the two sequencedPseudomonads, 976 protein-encoding genes are unique to Pss B728a whencompared to Pst DC3000, including large genomic islands likely tocontribute to virulence and host specificity. Over 375 repetitiveextragenic palindromic sequences (REPs) unique to Pss B728a when comparedto Pst DC3000 are widely distributed throughout the chromosome except in14 genomic islands, which generally had lower GC content than the genomeas a whole. Content of the genomic islands vary, with one containing aprophage and another the plasmid pKLC102 of P. aeruginosa PAO1. Among the976 genes of Pss B728a with no counterpart in Pst DC3000 are thoseencoding for …
Date: April 1, 2005
Creator: Feil, Helene; Feil, William S.; Chain, Patrick; Larimer, Frank; DiBartolo, Genevieve; Copeland, Alex et al.
System: The UNT Digital Library
Correlation of beam electron and LED signal losses under irradiation and long-term recovery of lead tungstate crystals (open access)

Correlation of beam electron and LED signal losses under irradiation and long-term recovery of lead tungstate crystals

None
Date: April 1, 2005
Creator: Batarin, V. A.; Butler, J.; Davidenko, A. M.; Derevschikov, A. A.; Goncharenko, Y. M.; Grishin, V. N. et al.
System: The UNT Digital Library
Dark matter dynamics and indirect detection (open access)

Dark matter dynamics and indirect detection

Non-baryonic, or ''dark'', matter is believed to be a major component of the total mass budget of the universe. We review the candidates for particle dark matter and discuss the prospects for direct detection (via interaction of dark matter particles with laboratory detectors) and indirect detection (via observations of the products of dark matter self-annihilations), focusing in particular on the Galactic center, which is among the most promising targets for indirect detection studies. The gravitational potential at the Galactic center is dominated by stars and by the supermassive black hole, and the dark matter distribution is expected to evolve on sub-parsec scales due to interaction with these components. We discuss the dominant interaction mechanisms and show how they can be used to rule out certain extreme models for the dark matter distribution, thus increasing the information that can be gleaned from indirect detection searches.
Date: April 1, 2005
Creator: Bertone, Gianfranco; /Fermilab; Merritt, David & Tech., /Rochester Inst.
System: The UNT Digital Library
Design Attributes and Scale Up Testing of Annular Centrifugal Contactors (open access)

Design Attributes and Scale Up Testing of Annular Centrifugal Contactors

Annular centrifugal contactors are being used for rapid yet efficient liquid- liquid processing in numerous industrial and government applications. Commercialization of this technology began eleven years ago and now units with throughputs ranging from 0.25 to 700 liters per minute are readily available. Separation, washing, and extraction processes all benefit from the use of this relatively new commercial tool. Processing advantages of this technology include: low in-process volume per stage, rapid mixing and separation in a single unit, connection-in-series for multi-stage use, and a wide operating range of input flow rates and phase ratios without adjustment. Recent design enhancements have been added to simplify maintenance, improve inspection ability, and provide increased reliability. Cartridge-style bearing and mechanical rotary seal assemblies that can include liquid-leak sensors are employed to enhance remote operations, minimize maintenance downtime, prevent equipment damage, and extend service life. Clean-in-place capability eliminates the need for disassembly, facilitates the use of contactors for feed clarification, and can be automated for continuous operation. In nuclear fuel cycle studies, aqueous based separations are being developed that efficiently partition uranium, actinides, and fission products via liquid-liquid solvent extraction. Thus, annular centrifugal contactors are destined to play a significant role in the design of …
Date: April 1, 2005
Creator: Meikrantz, David H. & Law, Jack D.
System: The UNT Digital Library
Design of a non-scaling FFAG accelerator for proton therapy (open access)

Design of a non-scaling FFAG accelerator for proton therapy

In recent years there has been a revival of interest in Fixed Field Alternating Gradient (FFAG) accelerators. In Japan a number have been built, or are under construction. A new non-scaling approach to the FFAG reduces the required orbit offsets during acceleration and the size of the required aperture, while maintaining the advantage of the low cost magnets associated with fixed fields. An advantage of the non-scaling FFAG accelerator, with respect to synchrotrons, is the fixed field and hence the possibility of high current and high repetition rate for spot scanning. There are possible advantages of the nonscaling design with respect to fixed-field cyclotrons. The non-scaling FFAG allows strong focusing and hence smaller aperture requirements compared to scaling designs, thus leading to very low losses and better control over the beam. We present, here, a non-scaling FFAG designed to be used for proton therapy.
Date: April 1, 2005
Creator: Trbojevic, D.; Ruggiero, A. G.; Keil, E.; Neskovic, N.; Belgrade, Vinca & Sessler, A.
System: The UNT Digital Library
Development of Technologies for the Simultaneous Separation of Cesium and Strontium from Spent Nuclear Fuel as Part of an Advanced Fuel Cycle (open access)

Development of Technologies for the Simultaneous Separation of Cesium and Strontium from Spent Nuclear Fuel as Part of an Advanced Fuel Cycle

As part of the Advanced Fuel Cycle Initiative, two solvent extraction technologies are being developed to simultaneously separate cesium and strontium from dissolved spent nuclear fuel. The first process utilizes a solvent consisting of chlorinated cobalt dicarbollide and polyethylene glycol extractants in a phenyltrifluoromethyl sulfone diluent. Recent improvements to the process include development of a new, non-nitroaromatic diluent and development of new stripping reagents, including a regenerable strip reagent that can be recovered and recycled. Countercurrent flowsheets have been designed and tested on simulated and actual spent nuclear fuel feed streams with both cesium and strontium removal efficiencies of greater than 99 %. The second process developed to simultaneously separate cesium and strontium from spent nuclear fuel is based on two highly-specific extractants: 4,4',(5')-Di-(t-butyldicyclo-hexano)-18-crown-6 (DtBuCH18C6) and Calix[4]arene-bis-(tert-octylbenzo-crown-6) (BOBCalixC6). The DtBuCH18C6 extractant is selective for strontium and the BOBCalixC6 extractant is selective for cesium. A solvent composition has been developed that enables both elements to be removed together and, in fact, a synergistic effect was observed with strontium distributions in the combined solvent that are much higher that in the strontium extraction (SREX) process. Initial laboratory test results of the new combined cesium and strontium extraction process indicate good extraction and …
Date: April 1, 2005
Creator: Law, Jack D.; HErbst, R. Scott; Meikrantz, David H.; Peterman, Dean R.; Riddle, Catherine L.; Tillotson, Richard D. et al.
System: The UNT Digital Library
Diet of southern toads (Bufo terrestris) in loblolly pine (Pinus taeda) stands subject to coarse woody debris manipulations. (open access)

Diet of southern toads (Bufo terrestris) in loblolly pine (Pinus taeda) stands subject to coarse woody debris manipulations.

ABSTRACT In the southeastern United States, coarse woody debris (CWD) typically harbors high densities of invertebrates. However, its importance as a foraging substrate for southeastern amphibians is relatively unknown. We examined effects of CWD manipulations on diet composition of southern toads (Bufo terrestris) in upland loblolly pine (Pinus taeda) stands in the Coastal Plain of South Carolina. Twelve 9.3-ha plots were assigned one of the following treatments: removal- all CWD _10 cm in diameter and _60 cm long removed; downed- five-fold increase in volume of down CWD; and unmanipulated control stands. We collected southern toads _4 cm snout-vent length (SVL) during 14 d sampling periods in June and October 2002, June 2003 and during a 28 d sampling period in April 2003. We collected 80, 36 and 35 southern toads in control, downed and removal treatments, respectively. We found no difference in relative abundance or frequency of invertebrate groups consumed among treatments (P.0.05). Average body weight (g), SVL (cm) and stomach content weight (g wet) of individuals also were similar among treatments (P . 0.05). The role of CWD as a foraging substrate for southern toads in loblolly pine stands of the southeastern Coastal Plain may be negligible, at least …
Date: April 1, 2005
Creator: Moseley, Kurtis R.; Castleberry, Steven B.; Hanula, James L. & Ford., Mark
System: The UNT Digital Library
Dopants and Defects in InN and InGaN Alloys (open access)

Dopants and Defects in InN and InGaN Alloys

We have performed systematic studies of the effects of high-energy particle irradiation on the properties of InGaN alloys. In agreement with the amphoteric defect model, irradiation of InN produces donor-like defects. The electron concentration increases with increasing radiation dose and saturates at 4 x 10{sup 20} cm{sup -3} at very high doses. We find that the increase of the electron concentration causes a large blue-shift of the absorption edge, which is well-explained by the Burstein-Moss effect. The maximum electron concentration decreases with increasing Ga fraction in irradiated In{sub 1-x}Ga{sub x}N alloys as the conduction band edge approaches the Fermi level stabilization energy (E{sub FS}). For x > 0.66 the conduction band edge moves above E{sub FS} and the irradiation of n-type films produces acceptor-like defects, resulting in a reduced free electron concentration. An analysis of the concentration dependence of the electron mobility in InN indicates that the dominant defects in irradiated InN are triply-charged donors. Finally, we show that InN films doped with Mg acceptors behave like undoped films above a threshold radiation dose.
Date: April 1, 2005
Creator: Walukiewicz, W.; Jones, R. E.; Li, S. X.; Yu, K. M.; Ager, J. W., III; Haller, E. E. et al.
System: The UNT Digital Library
DWPF Melter Glass Pump Implementation and Design Improvement (open access)

DWPF Melter Glass Pump Implementation and Design Improvement

In order to improve the melt rate of high level waste slurry feed being vitrified in the Savannah River Sites (SRS) Defense Waste Processing Facility (DWPF) Melter, a melter glass pump (pump 1) was installed in the DWPF Melter on February 10, 2004. The glass pump increased melt rate by generating a forced convection within the molten glass pool, thereby increasing the heat transfer from the molten glass to the unmolten feed cold cap that is on top of the glass pool. After operating for over four months, the pump was removed on June 22, 2004 due to indications that it had failed. The removed pump exhibited obvious signs of corrosion, had collapsed inward at the glass exit slots at the melt line, and was dog-legged in the same area. This lead to the pump being redesigned to improve its mechanical integrity (increased wall thickness and strength) while maintaining its hydraulic diameter as large as possible. The improved DWPF glass pump (pump 2) was installed on September 15, 2004. The impact of the new design on pump life, along with analysis of the glass pumps impact on melt rate in the DWPF Melter is discussed in this paper.
Date: April 1, 2005
Creator: Smith, Michael E.; Barnes, Allan B.; Bickford, Dennis F. & Iverson, Daniel C.
System: The UNT Digital Library
Electrical Properties of Carbon Fiber Support Systems (open access)

Electrical Properties of Carbon Fiber Support Systems

None
Date: April 1, 2005
Creator: Cooper, W.; Daly, C.; Demarteau, M.; Fast, J.; Hanagaki, K.; Johnson, M. et al.
System: The UNT Digital Library
Energy Storage Fuel Cell Vehicle Analysis: Preprint (open access)

Energy Storage Fuel Cell Vehicle Analysis: Preprint

In recent years, hydrogen fuel cell (FC) vehicle technology has received considerable attention as a strategy to decrease oil consumption and reduce harmful emissions. However, the cost, transient response, and cold performance of FC systems may present significant challenges to widespread adoption of the technology for transportation in the next 15 years. The objectives of this effort were to perform energy storage modeling with fuel cell vehicle simulations to quantify the benefits of hybridization and to identify a process for setting the requirements of ES for hydrogen-powered FC vehicles for U.S. Department of Energy's Energy Storage Program.
Date: April 1, 2005
Creator: Markel, T.; Pesaran, A.; Zolot, M.; Sprik, S.; Tataria, H. & Duong, T.
System: The UNT Digital Library
Evaluation of the Energy Performance of Six High-Performance Buildings: Preprint (open access)

Evaluation of the Energy Performance of Six High-Performance Buildings: Preprint

The energy performance of six high-performance buildings around the United States was monitored and evaluated by the NREL. The six buildings include the Visitor Center at Zion National Park, the NREL Thermal Test Facility, the Chesapeake Bay Foundation's Merrill Center, the BigHorn Home Improvement Center, the Cambria Office Building, and the Oberlin College Lewis Center.
Date: April 1, 2005
Creator: Torcellini, P. A.; Pless, S. & Crawley, D. B.
System: The UNT Digital Library
Exclusive Dijet production from CDF2LHC (open access)

Exclusive Dijet production from CDF2LHC

Exclusive dijet production at the Tevatron can be used as a benchmark to establish predictions on exclusive diffractive Higgs production, a process with a much smaller cross section. Exclusive dijet production in Double Pomeron Exchange processes, including diffractive Higgs production with measurements at the Tevatron and predictions for the Large Hadron Collider are presented. Using new data from the Tevatron and dedicated diffractive triggers, no excess over a smooth falling distribution for exclusive dijet events could be found. Upper limits on the exclusive dijet production cross section are presented and compared to current theoretical predictions.
Date: April 1, 2005
Creator: Gallinaro, Michele
System: The UNT Digital Library