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Glomus intraradices: Status of the Genome Project (open access)

Glomus intraradices: Status of the Genome Project

None
Date: September 1, 2008
Creator: Shapiro, Harris
Object Type: Article
System: The UNT Digital Library
INTEGRAL BENCHMARKS AVAILABLE THROUGH THE INTERNATIONAL REACTOR PHYSICS EXPERIMENT EVALUATION PROJECT AND THE INTERNATIONAL CRITICALITY SAFETY BENCHMARK EVALUATION PROJECT (open access)

INTEGRAL BENCHMARKS AVAILABLE THROUGH THE INTERNATIONAL REACTOR PHYSICS EXPERIMENT EVALUATION PROJECT AND THE INTERNATIONAL CRITICALITY SAFETY BENCHMARK EVALUATION PROJECT

Interest in high-quality integral benchmark data is increasing as efforts to quantify and reduce calculational uncertainties accelerate to meet the demands of next generation reactor and advanced fuel cycle concepts. The International Reactor Physics Experiment Evaluation Project (IRPhEP) and the International Criticality Safety Benchmark Evaluation Project (ICSBEP) continue to expand their efforts and broaden their scope to identify, evaluate, and provide integral benchmark data for method and data validation. Benchmark model specifications provided by these two projects are used heavily by the international reactor physics, nuclear data, and criticality safety communities. Thus far, 14 countries have contributed to the IRPhEP, and 20 have contributed to the ICSBEP. The status of the IRPhEP and ICSBEP is discussed in this paper, and the future of the two projects is outlined and discussed. Selected benchmarks that have been added to the IRPhEP and ICSBEP handbooks since PHYSOR’06 are highlighted, and the future of the two projects is discussed.
Date: September 1, 2008
Creator: Briggs, J. Blair; Scott, Lori; Sartori, Enrico & Rugama, Yolanda
Object Type: Article
System: The UNT Digital Library
Measurement of Resonance Parameters of Orbitally Excited Narrow B^0 Mesons (open access)

Measurement of Resonance Parameters of Orbitally Excited Narrow B^0 Mesons

The authors report a measurement of resonance parameters of the orbitally excited (L = 1) narrow B{sup 0} mesons in decays to B{sup (*)+}{pi}{sup -} using 1.7 fb{sup -1} of data collected by the CDF II detector at the Fermilab Tevatron. The mass and width of the B*{sub 2}{sup 0} state are measured to be m(B*{sub 2}{sup 0}) = 5740.2{sub -1.8}{sup +1.7}(stat.){sub -0.8}{sup +0.9}(syst.) MeV/c{sup 2} and {Lambda}(B*{sub 2}{sup 0}) = 22.7{sub -3.2}{sup +3.8}(stat.){sub -10.2}{sup +3.2}(syst.) MeV/c{sub 2}. The mass difference between the B*{sub 2}{sup 0} and B{sub 1}{sup 0} states is measured to be 14.9{sub -2.5}{sup +2.2}(stat.){sub -1.4}{sup +1.2}(syst.) MeV/c{sup 2}, resulting in a B{sub 1}{sup 0} mass of 5725.3{sub -2.2}{sup +1.6}(stat.){sub -1.5}{sup +1.4}(syst.) MeV/c{sup 2}. This is currently the most precise measurement of the masses of these states and the first measurement of the B*{sub 2}{sup 0} width.
Date: September 1, 2008
Creator: Aaltonen, : T.
Object Type: Article
System: The UNT Digital Library
Development of nanostructured and surface modified semiconductors for hybrid organic-inorganic solar cells. (open access)

Development of nanostructured and surface modified semiconductors for hybrid organic-inorganic solar cells.

Solar energy conversion is increasingly being recognized as one of the principal ways to meet future energy needs without causing detrimental environmental impact. Hybrid organic-inorganic solar cells (SCs) are attracting particular interest due to the potential for low cost manufacturing and for use in new applications, such as consumer electronics, architectural integration and light-weight sensors. Key materials advantages of these next generation SCs over conventional semiconductor SCs are in design opportunities--since the different functions of the SCs are carried out by different materials, there are greater materials choices for producing optimized structures. In this project, we explore the hybrid organic-inorganic solar cell system that consists of oxide, primarily ZnO, nanostructures as the electron transporter and poly-(3-hexylthiophene) (P3HT) as the light-absorber and hole transporter. It builds on our capabilities in the solution synthesis of nanostructured semiconducting oxide arrays to this photovoltaic (PV) technology. The three challenges in this hybrid material system for solar applications are (1) achieving inorganic nanostructures with critical spacing that matches the exciton diffusion in the polymer, {approx} 10 nm, (2) infiltrating the polymer completely into the dense nanostructure arrays, and (3) optimizing the interfacial properties to facilitate efficient charge transfer. We have gained an understanding and control …
Date: September 1, 2008
Creator: Hsu, Julia, W. P.
Object Type: Report
System: The UNT Digital Library
THE COMPONENT TEST FACILITY – A NATIONAL USER FACILITY FOR TESTING OF HIGH TEMPERATURE GAS-COOLED REACTOR (HTGR) COMPONENTS AND SYSTEMS (open access)

THE COMPONENT TEST FACILITY – A NATIONAL USER FACILITY FOR TESTING OF HIGH TEMPERATURE GAS-COOLED REACTOR (HTGR) COMPONENTS AND SYSTEMS

The Next Generation Nuclear Plant (NGNP) and other High-Temperature Gas-cooled Reactor (HTGR) Projects require research, development, design, construction, and operation of a nuclear plant intended for both high-efficiency electricity production and high-temperature industrial applications, including hydrogen production. During the life cycle stages of an HTGR, plant systems, structures and components (SSCs) will be developed to support this reactor technology. To mitigate technical, schedule, and project risk associated with development of these SSCs, a large-scale test facility is required to support design verification and qualification prior to operational implementation. As a full-scale helium test facility, the Component Test facility (CTF) will provide prototype testing and qualification of heat transfer system components (e.g., Intermediate Heat Exchanger, valves, hot gas ducts), reactor internals, and hydrogen generation processing. It will perform confirmation tests for large-scale effects, validate component performance requirements, perform transient effects tests, and provide production demonstration of hydrogen and other high-temperature applications. Sponsored wholly or in part by the U.S. Department of Energy, the CTF will support NGNP and will also act as a National User Facility to support worldwide development of High-Temperature Gas-cooled Reactor technologies.
Date: September 1, 2008
Creator: Duncan, David S.; Balls, Vondell J. & Austad, Stephanie L.
Object Type: Article
System: The UNT Digital Library
Geothermal Tomorrow 2008 (open access)

Geothermal Tomorrow 2008

Brochure describing the recent activities and future research direction of the DOE Geothermal Program.
Date: September 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Stereo soft x-ray microscopy and elemental mapping of hematite and clay suspensions (open access)

Stereo soft x-ray microscopy and elemental mapping of hematite and clay suspensions

The spatial arrangements of hematite particles within aqueous soil and clay samples are investigated with soft X-ray microscopy, taking advantage of the elemental contrast at the Fe-L edge around E = 707 eV. In combination with stereo microscopy, information about spatial arrangements are revealed and correlated to electrostatic interactions of the different mixtures. Manipulation of a sample mounted to the microscope is possible and particles added while imaging can be detected.
Date: September 1, 2008
Creator: Gleber, S.-C.; Thieme, J.; Chao, W. & Fischer, P.
Object Type: Article
System: The UNT Digital Library
NGNP Process Heat Utilization: Liquid Metal Phase Change Heat Exchanger (open access)

NGNP Process Heat Utilization: Liquid Metal Phase Change Heat Exchanger

One key long-standing issue that must be overcome to fully realize the successful growth of nuclear power is to determine other benefits of nuclear energy apart from meeting the electricity demands. The Next Generation Nuclear Plant (NGNP) will most likely be producing electricity and heat for the production of hydrogen and/or oil retrieval from oil sands and oil shale to help in our national pursuit of energy independence. For nuclear process heat to be utilized, intermediate heat exchange is required to transfer heat from the NGNP to the hydrogen plant or oil recovery field in the most efficient way possible. Development of nuclear reactor - process heat technology has intensified the interest in liquid metals as heat transfer media because of their ideal transport properties. Liquid metal heat exchangers are not new in practical applications. An important rational for considering liquid metals is the potential convective heat transfer is among the highest known. Thus explains the interest in liquid metals as coolant for intermediate heat exchange from NGNP. For process heat it is desired that, intermediate heat exchangers (IHX) transfer heat from the NGNP in the most efficient way possible. The production of electric power at higher efficiency via the …
Date: September 1, 2008
Creator: Sabharwall, Piyush; Patterson, Mike; Utgikar, Vivek & Gunnerson, Fred
Object Type: Article
System: The UNT Digital Library
Corrective Action Decision Document/ Closure Report for Corrective Action Unit 556: Dry Wells and Surface Release Points, Nevada Test Site, Nevada with Errata Sheet, Revision 0 (open access)

Corrective Action Decision Document/ Closure Report for Corrective Action Unit 556: Dry Wells and Surface Release Points, Nevada Test Site, Nevada with Errata Sheet, Revision 0

This Corrective Action Decision Document (CADD)/Closure Report (CR) has been prepared for Corrective Action Unit 556, Dry Wells and Surface Release Points, located at the Nevada Test Site, Nevada, in accordance with the Federal Facility Agreement and Consent Order (FFACO, 1996; as amended February 2008). Corrective Action Unit (CAU) 556 is comprised of four corrective action sites (CASs): • 06-20-04, National Cementers Dry Well • 06-99-09, Birdwell Test Hole • 25-60-03, E-MAD Stormwater Discharge and Piping • 25-64-01, Vehicle Washdown and Drainage Pit The purpose of this CADD/CR is to provide justification and documentation supporting the recommendation for closure of CAU 556 with no further corrective action. To achieve this, corrective action investigation (CAI) activities began on February 7 and were completed on June 19, 2008, as set forth in the Corrective Action Investigation Plan for Corrective Action Unit 556: Dry Wells and Surface Release Points, Nevada Test Site, Nevada (NNSA/NSO, 2007). The purpose of the CAI was to fulfill the following data needs as defined during the data quality objective (DQO) process: • Determine whether contaminants of concern (COCs) are present. • If COCs are present, determine their nature and extent. • Provide sufficient information and data to complete …
Date: September 1, 2008
Creator: Evenson, Grant
Object Type: Report
System: The UNT Digital Library
Geochemical Signatures as a Tool for Vermiculite Provenance Determination (open access)

Geochemical Signatures as a Tool for Vermiculite Provenance Determination

Thirty-eight samples of known origin (China, Libby MT, South Africa, South Carolina) and 6 vermiculite product samples of unknown origin were analyzed for major and trace elements, including rare earth elements to determine the feasibility of distinguishing the provenance of the samples based upon a geochemical signature. Probability plots suggest that two of the four groups (Libby, South Carolina) were comprised of two subgroups. Results of hierarchical cluster analysis are highly sensitive to the linkage method chosen. Ward’s method is the most useful for this data and suggests that there are five groups within the data set (South African samples, two subsets of the Libby samples, a subset of the South Carolina samples, and a second subset of the South Carolina samples combined with the China samples). Similar results were obtained using k-cluster analysis. Neither clustering method was able to distinguish samples from China from the South Carolina samples. Discriminant analysis was used on a four-category model comprised of the original four groups and on a six-category model comprised of the five categories identified from the cluster analysis but with the China samples grouped into a sixth category. The discriminant/classification model was able to distinguish all of the groups including …
Date: September 1, 2008
Creator: Wright, Karen E. & Palmer, Carl D.
Object Type: Report
System: The UNT Digital Library
Fuel Cell Vehicle Infrastructure Learning Demonstration: Status and Results; Preprint (open access)

Fuel Cell Vehicle Infrastructure Learning Demonstration: Status and Results; Preprint

Article prepared for ECS Transactions that describes the results of DOE's Controlled Hydrogen Fleet and Infrastructure Demonstration and Validation project.
Date: September 1, 2008
Creator: Wipke, K.; Sprik, S.; Kurtz, J. & Garbak, J.
Object Type: Report
System: The UNT Digital Library
The Advanced Test Reactor Irradiation Capabilities Available as a National Scientific User Facility (open access)

The Advanced Test Reactor Irradiation Capabilities Available as a National Scientific User Facility

The Advanced Test Reactor (ATR) is one of the world’s premiere test reactors for performing long term, high flux, and/or large volume irradiation test programs. The ATR is a very versatile facility with a wide variety of experimental test capabilities for providing the environment needed in an irradiation experiment. These capabilities include simple capsule experiments, instrumented and/or temperature-controlled experiments, and pressurized water loop experiment facilities. Monitoring systems have also been utilized to monitor different parameters such as fission gases for fuel experiments, to measure specimen performance during irradiation. ATR’s control system provides a stable axial flux profile throughout each reactor operating cycle, and allows the thermal and fast neutron fluxes to be controlled separately in different sections of the core. The ATR irradiation positions vary in diameter from 16 mm to 127 mm over an active core height of 1.2 m. This paper discusses the different irradiation capabilities with examples of different experiments and the cost/benefit issues related to each capability. The recent designation of ATR as a national scientific user facility will make the ATR much more accessible at very low to no cost for research by universities and possibly commercial entities.
Date: September 1, 2008
Creator: Grover, S. Blaine
Object Type: Article
System: The UNT Digital Library
B physics at CDF (open access)

B physics at CDF

We present the latest measurements on production, spectroscopy, lifetimes and branching fractions for b-mesons, b-baryons and quarkonia. We also discuss recent results on B{sub s}{sup 0} mixing as well as on CP violation for the B{sub s}{sup 0} meson and for b-baryons. These results were obtained by analyzing data collected by the CDF II detector at Fermilab.
Date: September 1, 2008
Creator: Papadimitriou, Vaia
Object Type: Article
System: The UNT Digital Library
Photovoltaics (open access)

Photovoltaics

Summarizes the goals and activities of the DOE Solar Energy Technologies Program efforts within its photovoltaics subprogram.
Date: September 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Heat Exchanger Design Options and Tritium Transport Study for the VHTR System (open access)

Heat Exchanger Design Options and Tritium Transport Study for the VHTR System

This report presents the results of a study conducted to consider heat exchanger options and tritium transport in a very high temperature reactor (VHTR) system for the Next Generation Nuclear Plant Project. The heat exchanger options include types, arrangements, channel patterns in printed circuit heat exchangers (PCHE), coolant flow direction, and pipe configuration in shell-and-tube designs. Study considerations include: three types of heat exchanger designs (PCHE, shell-and-tube, and helical coil); single- and two-stage unit arrangements; counter-current and cross flow configurations; and straight pipes and U-tube designs in shell-and-tube type heat exchangers. Thermal designs and simple stress analyses were performed to estimate the heat exchanger options, and the Finite Element Method was applied for more detailed calculations, especially for PCHE designs. Results of the options study show that the PCHE design has the smallest volume and heat transfer area, resulting in the least tritium permeation and greatest cost savings. It is theoretically the most reliable mechanically, leading to a longer lifetime. The two-stage heat exchanger arrangement appears to be safer and more cost effective. The recommended separation temperature between first and second stages in a serial configuration is 800oC, at which the high temperature unit is about one-half the size of …
Date: September 1, 2008
Creator: Oh, Chang H. & Kim, Eung S.
Object Type: Report
System: The UNT Digital Library
Third Quarter Hanford Seismic Report for Fiscal Year 2008 (open access)

Third Quarter Hanford Seismic Report for Fiscal Year 2008

The Hanford Seismic Assessment Program (HSAP) provides an uninterrupted collection of high-quality raw and processed seismic data from the Hanford Seismic Network for the U.S. Department of Energy and its contractors. The Hanford Seismic Assessment Team locates and identifies sources of seismic activity and monitors changes in the historical pattern of seismic activity at the Hanford Site. The data are compiled, archived, and published for use by the Hanford Site for waste management, natural phenomena hazards assessments, and engineering design and construction. In addition, the seismic monitoring organization works with the Hanford Site Emergency Services Organization to provide assistance in the event of a significant earthquake on the Hanford Site. The Hanford Seismic Network and the Eastern Washington Regional Network consist of 44 individual sensor sites and 15 radio relay sites maintained by the Hanford Seismic Assessment Team. For the Hanford Seismic Network, fourteen local earthquakes were recorded during the third quarter of fiscal year 2008. The largest event recorded by the network during the third quarter (May 18, 2008 - magnitude 3.7 Mc) was located approximately 17 km east of Prosser at a depth of 20.5 km. With regard to the depth distribution, five earthquakes occurred at shallow depths …
Date: September 1, 2008
Creator: Rohay, Alan C.; Sweeney, Mark D.; Hartshorn, Donald C.; Clayton, Ray E. & Devary, Joseph L.
Object Type: Report
System: The UNT Digital Library
Clean Cities Annual Metrics Report 2007 (open access)

Clean Cities Annual Metrics Report 2007

Document summarizes 2007 activity and accomplishments reported by Clean Cities coordinators.
Date: September 1, 2008
Creator: Johnson, C. & Bergeron, P.
Object Type: Report
System: The UNT Digital Library
Measurement of the Single Top Quark Production Cross Section at CDF (open access)

Measurement of the Single Top Quark Production Cross Section at CDF

We report a measurement of the single top quark production cross section in 2.2 fb{sup -1} of p{bar p} collision data collected by the Collider Detector at Fermilab at {radical}s = 1.96 TeV. Candidate events are classified as signal-like by three parallel analyses which use likelihood, matrix element, and neural network discriminants. These results are combined in order to improve the sensitivity. We observe a signal consistent with the standard model prediction, but inconsistent with the background only model by 3.7 standard deviations with a median expected sensitivity of 4.9 standard deviations. We measure a cross section of 2.2{sub -0.6}{sup +0.7}(stat+sys) pb, extract the CKM matrix element value |V{sub tb}| = 0.88{sub -0.12}{sup +0.13}(stat + sys) {+-} 0.07(theory), and set the limit |V{sub tb}| > 0.66 at the 95% C.L.
Date: September 1, 2008
Creator: Aaltonen, T.; Adelman, J.; Akimoto, T.; Albrow, Michael G.; Alvarez Gonzalez, B.; Amerio, S. et al.
Object Type: Article
System: The UNT Digital Library
Estimating Loss-of-Coolant Accident Frequencies for the Standardized Plant Analysis Risk Models (open access)

Estimating Loss-of-Coolant Accident Frequencies for the Standardized Plant Analysis Risk Models

The U.S. Nuclear Regulatory Commission maintains a set of risk models covering the U.S. commercial nuclear power plants. These standardized plant analysis risk (SPAR) models include several loss-of-coolant accident (LOCA) initiating events such as small (SLOCA), medium (MLOCA), and large (LLOCA). All of these events involve a loss of coolant inventory from the reactor coolant system. In order to maintain a level of consistency across these models, initiating event frequencies generally are based on plant-type average performance, where the plant types are boiling water reactors and pressurized water reactors. For certain risk analyses, these plant-type initiating event frequencies may be replaced by plant-specific estimates. Frequencies for SPAR LOCA initiating events previously were based on results presented in NUREG/CR-5750, but the newest models use results documented in NUREG/CR-6928. The estimates in NUREG/CR-6928 are based on historical data from the initiating events database for pressurized water reactor SLOCA or an interpretation of results presented in the draft version of NUREG-1829. The information in NUREG-1829 can be used several ways, resulting in different estimates for the various LOCA frequencies. Various ways NUREG-1829 information can be used to estimate LOCA frequencies were investigated and this paper presents two methods for the SPAR model standard …
Date: September 1, 2008
Creator: Eide, S. A.; Rasmuson, D. M. & Atwood, C. L.
Object Type: Article
System: The UNT Digital Library
Observation of transverse space charge effects in a multi-beamlet electron bunch produced in a photo-emission electron source (open access)

Observation of transverse space charge effects in a multi-beamlet electron bunch produced in a photo-emission electron source

A 'multiple beamlet' experiment aimed at investigating the transverse space charge effect was recently conducted at the Argonne Wakefield Accelerator. The experiment generated a symmetric pattern of 5 beamlets on the photocathode of the RF gun with the drive laser. We explored the evolution of the thereby produced 5 MeV, space-charge dominated electron beamlets in the 2m drift following the RF photocathode gun for various external focusing. Two important effects were observed and benchmarked using the particle-in-cell beam dynamics code IMPACT-T. In this paper, we present our experimental observation and their benchmarking with Impact-T.
Date: September 1, 2008
Creator: Rihaoui, M.; /Northern Illinois U. /NICADD, DeKalb; Gai, W.; /Argonne; Piot, P.; /Northern Illinois U. /NICADD, DeKalb /FERMILAB et al.
Object Type: Article
System: The UNT Digital Library
Market Transformation (open access)

Market Transformation

Summarizes the goals and activities of the DOE Solar Energy Technologies Program efforts within its market transformation subprogram.
Date: September 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
SYSTEM ANALYSIS OF NUCLEAR-ASSISTED SYNGAS PRODUCTION FROM COAL (open access)

SYSTEM ANALYSIS OF NUCLEAR-ASSISTED SYNGAS PRODUCTION FROM COAL

A system analysis has been performed to assess the efficiency and carbon utilization of a nuclear-assisted coal gasification process. The nuclear reactor is a high-temperature helium-cooled reactor that is used primarily to provide power for hydrogen production via high-temperature electrolysis. The supplemental hydrogen is mixed with the outlet stream from an oxygen-blown coal gasifier to produce a hydrogen-rich gas mixture, allowing most of the carbon dioxide to be converted into carbon monoxide, with enough excess hydrogen to produce a syngas product stream with a hydrogen/carbon monoxide molar ratio of about 2:1. Oxygen for the gasifier is also provided by the high-temperature electrolysis process. Results of the analysis predict 90.5% carbon utilization with a syngas production efficiency (defined as the ratio of the heating value of the produced syngas to the sum of the heating value of the coal plus the high-temperature reactor heat input) of 66.1% at a gasifier temperature of 1866 K for the high-moisture-content lignite coal considered. Usage of lower moisture coals such as bituminous can yield carbon utilization approaching 100% and 70% syngas production efficiency.
Date: September 1, 2008
Creator: Harvego, E. A.; McKellar, M. G. & O'Brien, J. E.
Object Type: Article
System: The UNT Digital Library
Cathode Ion Bombardment in RF Photoguns (open access)

Cathode Ion Bombardment in RF Photoguns

In this paper, we use the method of rapid oscillating field to solve the equation of ion motion in an RF gun. We apply the method to the BNL 1/2-cell SRF photogun and demonstrate that a significant portion of ions produced in the gun can reach the cathode if no special precautions are taken. Also, the paper proposes a simple mitigation recipe that can reduce the rate of ion bombardment.
Date: September 1, 2008
Creator: Pozdeyev, E.; Kayran, D. & Litvinenko, V.
Object Type: Report
System: The UNT Digital Library
Integrated Alignment Storage and Taxonomic Sorting for High-Throughput Sequencing (open access)

Integrated Alignment Storage and Taxonomic Sorting for High-Throughput Sequencing

None
Date: September 1, 2008
Creator: Shapiro, Harris
Object Type: Article
System: The UNT Digital Library