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National Bioenergy Center Biochemical Platform Integration Project Quarterly Update, Number 18, January-March 2008
Quarterly newsletter describing the activities of the National Bioenergy Center's Biochemical Platform Integration Project including ongoing research and goals.
Date:
April 2008
Creator:
National Renewable Energy Laboratory (U.S.)
Object Type:
Journal/Magazine/Newsletter
System:
The UNT Digital Library
First Observation of the Cabibbo-suppressed Decays Xi+(c) ---> Sigma+ pi- pi+ and Xi+(c) ---> Sigma- pi+ pi+ and Measurement of their Branching Ratios
The authors report the first observation of two Cabibbo-suppressed decay modes, {Xi}{sub c}{sup +} {yields} {Sigma}{sup +}{pi}{sup -}{pi}{sup +} and {Xi}{sub c}{sup +} {yields} {Sigma}{sup -} {pi}{sup +}{pi}{sup +}. They observe 56 {+-} 13 over a background of 21, and 23 {+-} 7 over a background of 12 events, respectively, for the signals. The data were accumulated using the SELEX spectrometer during the 1996-1997 fixed target run at Fermilab, chiefly from a 600 GeV/c {Sigma}{sup -} beam. The branching ratios of the decays relative to the Cabibbo-favored {Xi}{sub c}{sup +} {yields} {Xi}{sup -}{pi}{sup +}{pi}{sup +} are measured to be B({Xi}{sub c}{sup +} {yields} {Sigma}{sup +}{pi}{sup -}{pi}{sup +})/B({xi}{sub c}{sup +} {yields} {Xi}{sup -} {pi}{sup +}{pi}{sup +}) = 0.50 {+-} 0.20, and B({Xi}{sub c}{sup +} {yields} {Sigma}{sup -}{pi}{sup +}{pi}{sup +})/B({Xi}{sub c}{sup +} {yields} {Xi}{sup -}{pi}{sup +}{pi}{sup +}) = 0.23 {+-} 0.11, respectively. They also report branching ratios for the same decay modes of the {Lambda}{sub c}{sup +} relative to {Lambda}{sub c}{sup +} {yields} pK{sup -}{pi}{sup +}.
Date:
April 1, 2008
Creator:
Vazquez-Jauregui, E.; U., /San Luis Potosi; Engelfried, J.; U., /San Luis Potosi; Akgun, U.; U., /Iowa et al.
Object Type:
Article
System:
The UNT Digital Library
Predicting Pattern Tooling and Casting Dimensions for Investment Casting, Phase III
Efforts during Phase III focused mainly on the shell-alloy systems. A high melting point alloy, 17-4PH stainless steel, was considered. The experimental part of the program was conducted at ORNL and commercial foundries, where wax patterns were injected, molds were invested, and alloys were poured. Shell molds made of fused-silica and alumino-silicates were considered. A literature review was conducted on thermophysical and thermomechanical properties alumino-silicates. Material property data, which were not available from material suppliers, was obtained. For all the properties of 17-4PH stainless steel, the experimental data available in the literature did not cover the entire temperature range necessary for process simulation. Thus, some material properties were evaluated using ProCAST, based on CompuTherm database. A comparison between the predicted material property data and measured property data was made. It was found that most material properties were accurately predicted only over several temperature ranges. No experimental data for plastic modulus were found. Thus, several assumptions were made and ProCAST recommendations were followed in order to obtain a complete set of mechanical property data at high temperatures. Thermal expansion measurements for the 17-4PH alloy were conducted during heating and cooling. As a function of temperature, the thermal expansion for both the …
Date:
April 1, 2008
Creator:
Sabau, Adrian S
Object Type:
Report
System:
The UNT Digital Library
Chemical Kinetic Modeling of Hydrogen Combustion Limits
A detailed chemical kinetic model is used to explore the flammability and detonability of hydrogen mixtures. In the case of flammability, a detailed chemical kinetic mechanism for hydrogen is coupled to the CHEMKIN Premix code to compute premixed, laminar flame speeds. The detailed chemical kinetic model reproduces flame speeds in the literature over a range of equivalence ratios, pressures and reactant temperatures. A series of calculation were performed to assess the key parameters determining the flammability of hydrogen mixtures. Increased reactant temperature was found to greatly increase the flame speed and the flammability of the mixture. The effect of added diluents was assessed. Addition of water and carbon dioxide were found to reduce the flame speed and thus the flammability of a hydrogen mixture approximately equally well and much more than the addition of nitrogen. The detailed chemical kinetic model was used to explore the detonability of hydrogen mixtures. A Zeldovich-von Neumann-Doring (ZND) detonation model coupled with detailed chemical kinetics was used to model the detonation. The effectiveness on different diluents was assessed in reducing the detonability of a hydrogen mixture. Carbon dioxide was found to be most effective in reducing the detonability followed by water and nitrogen. The chemical …
Date:
April 2, 2008
Creator:
Pitz, W J & Westbrook, C K
Object Type:
Report
System:
The UNT Digital Library
A Title 40 Code of Federal Regulations Part 191 Evaluation of Buried Transuranic Waste at the Nevada Test Site
In 1986, 21 m{sup 3} of transuranic (TRU) waste was inadvertently buried in a shallow land burial trench at the Area 5 Radioactive Waste Management Site on the Nevada Test Site (NTS). The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office is considered five options for management of the buried TRU waste. One option is to leave the waste in-place if the disposal can meet the requirements of Title 40 Code of Federal Regulations (CFR) Part 191, 'Environmental Radiation Protection Standard for Management and Disposal of Spent Nuclear Fuel, High-Level, and Transuranic Radioactive Wastes'. This paper describes analyses that assess the likelihood that TRU waste in shallow land burial can meet the 40 CFR 191 standards for a geologic repository. The simulated probability of the cumulative release exceeding 1 and 10 times the 40 CFR 191.13 containment requirements is estimated to be 0.009 and less than 0.0001, respectively. The cumulative release is most sensitive to the number of groundwater withdrawal wells drilled through the disposal trench. The mean total effective dose equivalent for a member of the public is estimated to reach a maximum of 0.014 milliSievert (mSv) at 10,000 years, or approximately 10 percent of the …
Date:
April 1, 2008
Creator:
G. J. Shott, V. Yucel, L. Desotell
Object Type:
Article
System:
The UNT Digital Library
A Single-band Cold Mass Support System for the MICE Superconducting Coupling Magnet
The cooling channel of the Muon Ionization Cooling Experiment (MICE) consists of eighteen superconducting solenoid coils, which are magnetically hooked together and contained in seven modules. The operations of a pair of MICE superconducting coupling magnets are affected directly by the other solenoid coils in the MICE channel. In order to meet the stringent requirement for the magnet center and axis azimuthal angle at 4.2 K, a self-centered tension-band cold mass support system with intermediate thermal interruption was applied for the MICE superconducting coupling magnet. The physical center of the magnet does not change as it is cooled down from 300 K to 4.2 K using this support system. This paper analyzed and calculated force loads on the coupling magnet under various operation modes of the MICE cooling channel. The performance parameters of a single-band cold mass support system were calculated also.
Date:
April 2, 2008
Creator:
Wu, Hong; Wang, Li; Liu, X.K.; Liu, C.S.; Li, L.K.; Xu, Feng Yu et al.
Object Type:
Article
System:
The UNT Digital Library
Quantifying uncertainties of a Soil-Foundation Structure-Interaction System under Seismic Excitation
We applied a spectrum of uncertainty quantification (UQ) techniques to the study of a two-dimensional soil-foundation-structure-interaction (2DSFSI) system (obtained from Professor Conte at UCSD) subjected to earthquake excitation. In the process we varied 19 uncertain parameters describing material properties of the structure and the soil. We present in detail the results for the different stages of our UQ analyses.
Date:
April 7, 2008
Creator:
Tong, C
Object Type:
Report
System:
The UNT Digital Library
DOECGF 2008 Site Report
The Data group provides data analysis and visualization support to its customers. This consists primarily of the development and support of VisIt, a data analysis and visualization tool. Support ranges from answering questions about the tool, providing classes on how to use the tool, and performing data analysis and visualization for customers. The Information Management and Graphics Group supports and develops tools that enhance our ability to access, display, and understand large, complex data sets. Activities include applying visualization software for terascale data exploration; running two video production labs; supporting graphics libraries and tools for end users; maintaining PowerWalls and assorted other displays; and developing software for searching, managing, and browsing scientific data. Researchers in the Center for Applied Scientific Computing (CASC) work on various projects including the development of visualization techniques for terascale data exploration that are funded by the ASC program, among others. The researchers also have LDRD projects and collaborations with other lab researchers, academia, and industry. During the past year we have completed our visualization cluster strategy of converting to Opteron/IB clusters. We support a 128-node Opteron/IB cluster providing a visualization production server for our unclassified systems and a 256-node Opteron/IB cluster for the classified systems, …
Date:
April 23, 2008
Creator:
Springmeyer, R & Brugger, E
Object Type:
Report
System:
The UNT Digital Library
Radiographic Capabilities of the MERCURY Monte Carlo Code
MERCURY is a modern, parallel, general-purpose Monte Carlo code being developed at the Lawrence Livermore National Laboratory. Recently, a radiographic capability has been added. MERCURY can create a source of diagnostic, virtual particles that are aimed at pixels in an image tally. This new feature is compared to the radiography code, HADES, for verification and timing. Comparisons for accuracy were made using the French Test Object and for timing were made by tracking through an unstructured mesh. In addition, self consistency tests were run in MERCURY for the British Test Object and scattering test problem. MERCURY and HADES were found to agree to the precision of the input data. HADES appears to run around eight times faster than the MERCURY in the timing study. Profiling the MERCURY code has turned up several differences in the algorithms which account for this. These differences will be addressed in a future release of MERCURY.
Date:
April 7, 2008
Creator:
McKinley, M. Scott & Schach von Wittenau, Alexis E.
Object Type:
Article
System:
The UNT Digital Library
EE&RE, Session: CdTe - Progress and Roadmap Alignment
This project supports the Solar America Initiative by: (1) assistance to SAI Incubators (Primestar Solar, AvA Solar); (2) providing industry with baseline understanding of CdS/CdTe device formation and reliability--incorporation of low-cost, high quality TCOs, functionality and options for buffer layers, effect of various CdS options, effect of and importance CdSTe alloy formation, effect and options for CdCl{sub 2} treatment, effect and options for back contact, and effect of residual impurities during all stages of device formation; (3) understanding modes and mechanisms of cell-level stability; and (4) establishment of CdTe PDIL Tool for rapid material and process screening.
Date:
April 1, 2008
Creator:
Gessert, T.
Object Type:
Presentation
System:
The UNT Digital Library
Habitat-Lite: A GSC case study based on free text terms for environmental metadata
There is an urgent need to capture metadata on the rapidly growing number of genomic, metagenomic and related sequences, such as 16S ribosomal genes. This need is a major focus within the Genomic Standards Consortium (GSC), and Habitat is a key metadata descriptor in the proposed 'Minimum Information about a Genome Sequence' (MIGS) specification. The goal of the work described here is to provide a light-weight, easy-to-use (small) set of terms ('Habitat-Lite') that captures high-level information about habitat while preserving a mapping to the recently launched Environment Ontology (EnvO). Our motivation for building Habitat-Lite is to meet the needs of multiple users, such as annotators curating these data, database providers hosting the data, and biologists and bioinformaticians alike who need to search and employ such data in comparative analyses. Here, we report a case study based on semi-automated identification of terms from GenBank and GOLD. We estimate that the terms in the initial version of Habitat-Lite would provide useful labels for over 60% of the kinds of information found in the GenBank isolation-source field, and around 85% of the terms in the GOLD habitat field. We present a revised version of Habitat-Lite and invite the community's feedback on its further …
Date:
April 1, 2008
Creator:
Kyrpides, Nikos; Hirschman, Lynette; Clark, Cheryl; Cohen, K. Bretonnel; Mardis, Scott; Luciano, Joanne et al.
Object Type:
Article
System:
The UNT Digital Library
Implementation of an interactive matching scheme for the Kapchinskij-Vladimirskij equations in the WARP code
The WARP code is a robust electrostatic particle-in-cell simulation package used to model charged particle beams with strong space-charge forces. A fundamental operation associated with seeding detailed simulations of a beam transport channel is to generate initial conditions where the beam distribution is matched to the structure of a periodic focusing lattice. This is done by solving for periodic, matched solutions to a coupled set of ODEs called the Kapchinskij-Vladimirskij (KV) envelope equations, which describe the evolution of low-order beam moments subject to applied lattice focusing, space-charge defocusing, and thermal defocusing forces. Recently, an iterative numerical method was developed (Lund, Chilton, and Lee, Efficient computation of matched solutions to the KV envelope equations for periodic focusing lattices, Physical Review Special Topics-Accelerators and Beams 9, 064201 2006) to generate matching conditions in a highly flexible, convergent, and fail-safe manner. This method is extended and implemented in the WARP code as a Python package to vastly ease the setup of detailed simulations. In particular, the Python package accommodates any linear applied lattice focusing functions without skew coupling, and a more general set of beam parameter specifications than its predecessor. Lattice strength iteration tools were added to facilitate the implementation of problems with …
Date:
April 15, 2008
Creator:
Chilton, Sven H.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
ACRF Ingest Software Status: New, Current, and Future - April 2008
The purpose of this report is to provide status of the ingest software used to process instrument data for the Atmospheric Radiation Measurement Program Climate Research Facility (ACRF). The report is divided into 4 sections: (1) for news about ingests currently under development, (2) for current production ingests, (3) for future ingest development plans, and (4) for information on retired ingests. Please note that datastreams beginning in “xxx” indicate cases where ingests run at multiple ACRF sites, which results in a datastream(s) for each location.
Date:
April 1, 2008
Creator:
Koontz, A. S.; Choudhury, S.; Ermold, B. D.; Keck, N. N.; Gaustad, K. L. & Perez, R. C.
Object Type:
Report
System:
The UNT Digital Library
An Automated Implementation of On-shell Methods for One-Loop Amplitudes
None
Date:
April 11, 2008
Creator:
Berger, C.F.; Bern, Z.; Dixon, L.J.; Febres Cordero, F.; Forde, D.; Ita, H. et al.
Object Type:
Article
System:
The UNT Digital Library
Measurements of Top Quark Properties at the Tevatron
None
Date:
April 1, 2008
Creator:
Eusebi, Ricardo
Object Type:
Article
System:
The UNT Digital Library
Barium in Twilight Zone suspended matter as a potential proxy for particulate organic carbon remineralization: Results for the North Pacific
This study focuses on the fate of exported organic carbon in the twilight zone at two contrasting environments in the North Pacific: the oligotrophic ALOHA site (22 degrees 45 minutes N 158 degrees W; Hawaii; studied during June-July 2004) and the mesotrophic Subarctic Pacific K2 site (47 degrees N, 161 degrees W; studied during July-August 2005). Earlier work has shown that non-lithogenic, excess particulate Ba (Ba{sub xs}) in the mesopelagic water column is a potential proxy of organic carbon remineralization. In general Ba{sub xs} contents were significantly larger at K2 than at ALOHA. At ALOHA the Ba{sub xs} profiles from repeated sampling (5 casts) showed remarkable consistency over a period of three weeks, suggesting that the system was close to being at steady state. In contrast, more variability was observed at K2 (6 casts sampled) reflecting the more dynamic physical and biological conditions prevailing in this environment. While for both sites Ba{sub xs} concentrations increased with depth, at K2 a clear maximum was present between the base of the mixed layer at around 50m and 500m, reflecting production and release of Ba{sub xs}. Larger mesopelagic Ba{sub xs} contents and larger bacterial production in the twilight zone at the K2 site …
Date:
April 10, 2008
Creator:
Dehairs, F.; Jacquet, S.; Savoye, N.; Van Mooy, B. A. S.; Buesseler, K.; Bishop, J. K. B. et al.
Object Type:
Article
System:
The UNT Digital Library
IMPLEMENTING CHANGES TO AN APPROVED AND IN-USE DOCUMENTED SAFETY ANALYSIS
None
Date:
April 9, 2008
Creator:
JP, KING
Object Type:
Article
System:
The UNT Digital Library
WW production cross section measurement and limits on anomalous trilinear gauge couplings at sqrt(s) = 1.96-TeV
The cross section for WW production is measured and limits on anomalous WW{gamma} and WWZ trilinear gauge couplings are set using WW {yields} ee/e{mu}/{mu}{mu} events collected by the Run II D0 detector at the Fermilab Tevatron Collider corresponding to 1 fb{sup -1} of integrated luminosity at {radical}s = 1.96 TeV. Across the three final states, 108 candidate events are observed with 40.8 {+-} 3.8 total background expected, consistent with {sigma}(p{bar p} {yields} WW) = 11.6 {+-} 1.8(stat) {+-} 0.7(syst) {+-} 0.7(lumi) pb. Using a set of SU(2){sub L} {direct_product} U(1){sub Y} conserving constraints, the one-dimensional 95% C.L. limits on trilinear gauge couplings are -0.63 < {Delta}{kappa}{sub {gamma}} < 0.99, -0.15 < {lambda}{sub {gamma}} < 0.19, and -0.14 < {Delta}g{sub 1}{sup Z} < 0.34.
Date:
April 1, 2008
Creator:
Cooke, Michael P. & U., /Rice
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
PBXN-9 Ignition Kinetics and Deflagration Rates
The ignition kinetics and deflagration rates of PBXN-9 were measured using specially designed instruments at LLNL and compared with previous work on similar HMX based materials. Ignition kinetics were measured based on the One Dimensional Time-to-Explosion combined with ALE3D modeling. Results of these experiments indicate that PBXN-9 behaves much like other HMX based materials (i.e. LX-04, LX-07, LX-10 and PBX-9501) and the dominant factor in these experiments is the type of explosive, not the type of binder/plasticizer. In contrast, the deflagration behavior of PBXN-9 is quite different from similar high weight percent HMX based materials (i.e LX-10, LX-07 and PBX-9501). PBXN-9 burns in a laminar manner over the full pressure range studied (0-310 MPa) unlike LX-10, LX-07, and PBX-9501. The difference in deflagration behavior is attributed to the nature of the binder/plasticizer alone or in conjunction with the volume of binder present in PBXN-9.
Date:
April 24, 2008
Creator:
Glascoe, E; Maienschein, J; Burnham, A; Koerner, J; Hsu, P & Wemhoff, A.
Object Type:
Article
System:
The UNT Digital Library
Formulation of Moist Dynamics and Physics for Future Climate Models
In this project, one of our goals is to develop atmospheric models, in which innovative ideas on improving the quality of moisture predictions can be tested. Our other goal is to develop an explicit time integration scheme based on the multi-point differencing that does the same job as an implicit trapezoidal scheme but uses information only from limited number of grid points.
Date:
April 30, 2008
Creator:
Arakwa, Celal S. Konor and Akio
Object Type:
Text
System:
The UNT Digital Library
Envisioning the Solar Program Beyond the Solar America Initiative (SAI)
None
Date:
April 1, 2008
Creator:
Margolis, R. M.
Object Type:
Presentation
System:
The UNT Digital Library
Long Duration Testing of Type C Thermocouples at 1500 °C
Experience with Type C thermocouples operating for long periods in the 1400 to 1600 °C temperature range indicate that significant decalibration occurs, often leading to expensive downtime and material waste. As part of an effort to understand the mechanisms causing drift in these thermocouples, the Idaho National Laboratory conducted a long duration test at 1500 °C containing eight Type C thermocouples. As report in this document, results from this long duration test were adversely affected due to oxygen ingress. Nevertheless, results provide key insights about the impact of precipitate formation on thermoelectric response. Post-test examinations indicate that thermocouple signal was not adversely impacted by the precipitates detected after 1,000 hours of heating at 1,500 °C and suggest that the signal would not have been adversely impacted by these precipitates for longer durations (if oxygen ingress had not occurred in this test).
Date:
April 1, 2008
Creator:
Rempe, Joy L.; Knudson, Darrell L.; Daw, J. E. & Wilkins, S. C.
Object Type:
Report
System:
The UNT Digital Library
Ultrabright Laser-based MeV-class Light Source
We report first light from a novel, new source of 10-ps 0.776-MeV gamma-ray pulses known as T-REX (Thomson-Radiated Extreme X-rays). The MeV-class radiation produced by TREX is unique in the world with respect to its brightness, spectral purity, tunability, pulse duration and laser-like beam character. With T-REX, one can use photons to efficiently probe and excite the isotope-dependent resonant structure of atomic nucleus. This ability will be enabling to an entirely new class of isotope-specific, high resolution imaging and detection capabilities.
Date:
April 2, 2008
Creator:
Albert, F.; Anderson, G.; Anderson, S.; Bayramian, A.; Berry, B.; Betts, S. et al.
Object Type:
Article
System:
The UNT Digital Library
Clean Cities Fact Sheet, April 2008
Fact sheet describing Clean Cities, a DOE program that deploys alternative and advanced fuels and vehicles to displace petroleum in the transportation sector. It includes the contact information for its 86 active coalitions.
Date:
April 2008
Creator:
United States. Department of Energy. Office of Energy Efficiency and Renewable Energy.
Object Type:
Pamphlet
System:
The UNT Digital Library