Development of a Hydronic Rooftop Unit-HyPak-MA (open access)

Development of a Hydronic Rooftop Unit-HyPak-MA

The majority of U.S. commercial floor space is cooled by rooftop HVAC units (RTUs). RTU popularity derives chiefly from their low initial cost and relative ease of service access without disturbing building occupants. Unfortunately, current RTUs are inherently inefficient due to a combination of characteristics that unnecessarily increase cooling loads and energy use. 36% percent of annual U.S. energy, and two-thirds of electricity, is consumed in and by buildings. Commercial buildings consume approximately 4.2 quads of energy each year at a cost of $230 billion per year, with HVAC equipment consuming 1.2 quads of electricity. More than half of all U.S. commercial floor space is cooled by packaged HVAC units, most of which are rooftop units (RTUs). Inefficient RTUs create an estimated 3.5% of U.S. CO{sub 2} emissions, thus contributing significantly to global warming5. Also, RTUs often fail to maintain adequate ventilation air and air filtration, reducing indoor air quality. This is the second HyPak project to be supported by DOE through NETL. The prior project, referred to as HyPak-1 in this report, had two rounds of prototype fabrication and testing as well as computer modeling and market research. The HyPak-1 prototypes demonstrated the high performance capabilities of the HyPak …
Date: November 14, 2009
Creator: Lee, Eric & Berman, Mark
Object Type: Report
System: The UNT Digital Library
Oxbow Fish Hatchery Snake River Sockeye Salmon Smolt Program, 2008 Annual Report. (open access)

Oxbow Fish Hatchery Snake River Sockeye Salmon Smolt Program, 2008 Annual Report.

This contract proposal is in response to the Federal Columbia River Power System Biological Opinion Implementation Plan/Update Proposed Action (UPA) associated with increasing the number of Snake River sockeye smolts by 150,000. To accomplish this proposal the cooperation and efforts of three government entities has been planned (e.g., Idaho Department of Fish and Game (IDFG), Oregon Department of Fish and Wildlife (ODFW), and the National Marine Fisheries Service (NMFS)). Improvements at the IDFG Eagle Fish Hatchery and NMFS Burley Creek Hatchery will focus on increasing sockeye salmon captive broodstock and egg production. Improvements at the ODFW Oxbow Fish Hatchery will be made to accommodate the incubation, hatching and rearing of 150,000 sockeye salmon smolts for release into Idaho's Sawtooth Valley, Upper Salmon River near IDFG's Sawtooth Fish Hatchery and/or Redfish Lake Creek 1.4 km downstream of Redfish Lake. Modifications to Oxbow Fish Hatchery (ODFW) will include retro-fit existing pond drains so pond cleaning effluent water can be routed to the pollution abatement pond, and modifications to the abatement pond. Also included in this project as an added phase, was the rerouting of the hatchery building effluent water to meet state DEQ guidelines for the use of formalin to treat salmonid …
Date: November 14, 2009
Creator: Banks, Duane D.
Object Type: Report
System: The UNT Digital Library
Santa Clara County Planar Solid Oxide Fuel Cell Demonstration Project (open access)

Santa Clara County Planar Solid Oxide Fuel Cell Demonstration Project

The Santa Clara County Planar Solid Oxide Fuel Cell (PSOFC) project demonstrated the technical viability of pre-commercial PSOFC technology at the County 911 Communications headquarters, as well as the input fuel flexibility of the PSOFC. PSOFC operation was demonstrated on natural gas and denatured ethanol. The Santa Clara County Planar Solid Oxide Fuel Cell (PSOFC) project goals were to acquire, site, and demonstrate the technical viability of a pre-commercial PSOFC technology at the County 911 Communications headquarters. Additional goals included educating local permit approval authorities, and other governmental entities about PSOFC technology, existing fuel cell standards and specific code requirements. The project demonstrated the Bloom Energy (BE) PSOFC technology in grid parallel mode, delivering a minimum 15 kW over 8760 operational hours. The PSOFC system demonstrated greater than 81% electricity availability and 41% electrical efficiency (LHV net AC), providing reliable, stable power to a critical, sensitive 911 communications system that serves geographical boundaries of the entire Santa Clara County. The project also demonstrated input fuel flexibility. BE developed and demonstrated the capability to run its prototype PSOFC system on ethanol. BE designed the hardware necessary to deliver ethanol into its existing PSOFC system. Operational parameters were determined for running the …
Date: November 14, 2009
Creator: Mitlitsky, Fred; Mulhauser, Sara; Chien, David; Shukla, Deepak & Weingaertner, David
Object Type: Report
System: The UNT Digital Library
A Systems Analysis of the Chemosensitivity of Breast Cancer Cells to the Polyamine Analogue PG-11047 (open access)

A Systems Analysis of the Chemosensitivity of Breast Cancer Cells to the Polyamine Analogue PG-11047

Polyamines regulate important cellular functions and polyamine dysregulation frequently occurs in cancer. The objective of this study was to use a systems approach to study the relative effects of PG-11047, a polyamine analogue, across breast cancer cells derived from different patients and to identify genetic markers associated with differential cytotoxicity. A panel of 48 breast cell lines that mirror many transcriptional and genomic features present in primary human breast tumours were used to study the antiproliferative activity of PG-11047. Sensitive cell lines were further examined for cell cycle distribution and apoptotic response. Cell line responses, quantified by the GI50 (dose required for 50% relative growth inhibition) were correlated with the omic profiles of the cell lines to identify markers that predict response and cellular functions associated with drug sensitivity. The concentrations of PG-11047 needed to inhibit growth of members of the panel of breast cell lines varied over a wide range, with basal-like cell lines being inhibited at lower concentrations than the luminal cell lines. Sensitive cell lines showed a significant decrease in S phase fraction at doses that produced little apoptosis. Correlation of the GI50 values with the omic profiles of the cell lines identified genomic, transcriptional and proteomic …
Date: November 14, 2009
Creator: Kuo, Wen-Lin; Das, Debopriya; Ziyad, Safiyyah; Bhattacharya, Sanchita; Gibb, William J.; Heiser, Laura M. et al.
Object Type: Article
System: The UNT Digital Library
Accelerating scientific discovery : 2007 annual report. (open access)

Accelerating scientific discovery : 2007 annual report.

As a gateway for scientific discovery, the Argonne Leadership Computing Facility (ALCF) works hand in hand with the world's best computational scientists to advance research in a diverse span of scientific domains, ranging from chemistry, applied mathematics, and materials science to engineering physics and life sciences. Sponsored by the U.S. Department of Energy's (DOE) Office of Science, researchers are using the IBM Blue Gene/L supercomputer at the ALCF to study and explore key scientific problems that underlie important challenges facing our society. For instance, a research team at the University of California-San Diego/ SDSC is studying the molecular basis of Parkinson's disease. The researchers plan to use the knowledge they gain to discover new drugs to treat the disease and to identify risk factors for other diseases that are equally prevalent. Likewise, scientists from Pratt & Whitney are using the Blue Gene to understand the complex processes within aircraft engines. Expanding our understanding of jet engine combustors is the secret to improved fuel efficiency and reduced emissions. Lessons learned from the scientific simulations of jet engine combustors have already led Pratt & Whitney to newer designs with unprecedented reductions in emissions, noise, and cost of ownership. ALCF staff members provide …
Date: November 14, 2008
Creator: Beckman, P.; Dave, P. & Drugan, C.
Object Type: Report
System: The UNT Digital Library
Accessing tri-gluon correlations in the nucleon via the singlespin asymmetry in open charm production (open access)

Accessing tri-gluon correlations in the nucleon via the singlespin asymmetry in open charm production

We calculate the single transverse-spin asymmetry for open charm production in pp collisions within the QCD collinear factorization approach. We include contributions from both twist-three quark-gluon and tri-gluon correlation functions. We find that the quark-gluon correlation functions alone generate only a very small asymmetry for open charm production in the kinematic region of current interest at RHIC, so that the observation of any significant single-spin asymmetry would be a clear indication of the presence of tri-gluon correlations inside a polarized proton. We furthermore demonstrate that the tri-gluon contribution could be very different for the production of D and \bar{D} mesons. These features make the single spin asymmetry in open charm production in polarized pp collisions at RHIC an excellent probe of tri-gluon correlation functions.
Date: November 14, 2008
Creator: Kang, Zhong-Bo; Qiu, Jian-Wei; Vogelsang, Werner & Yuan, Feng
Object Type: Article
System: The UNT Digital Library
Analysis of Cost-Effective Off-Board Hydrogen Storage and Refueling Stations (open access)

Analysis of Cost-Effective Off-Board Hydrogen Storage and Refueling Stations

This report highlights design and component selection considerations for compressed gas hydrogen fueling stations operating at 5000 psig or 350 bar. The primary focus is on options for compression and storage – in terms of practical equipment options as well as various system configurations and how they influence delivery performance and station economics.
Date: November 14, 2008
Creator: Barnes, Ted & Liss, William
Object Type: Report
System: The UNT Digital Library
Multiple-Coincidence Active Neutron Interrogation of Fissionable Materials (open access)

Multiple-Coincidence Active Neutron Interrogation of Fissionable Materials

In an extension of the Associated Particle Imaging technique that is used for the detection and imaging of hidden explosives, the present measurements use a beam of tagged 14.1 MeV neutrons in coincidence with two or more gammas to probe for the presence of fissionable materials. We have measured neutron-gamma-gamma coincidences with targets of depleted uranium, tungsten, lead, iron, and carbon and will present results that show the multiple-coincidence counting rate for the depleted uranium is substantially higher than any of the non-fissionable materials. In addition, the presence of coincidences involving delayed particle spectra provides a signature for fissionable materials that is distinct from that for non-fissionable ones. Information from the tagged neutron involved in the coincidence event is used to compute the position of the fissionable material in all three dimensions. The result is an imaging probe for fissionable materials that is compact and portable, and produces relatively low levels of background radiation. Simultaneous measurements on packages of interest for both explosives and fissionable materials are now feasible.
Date: November 14, 2008
Creator: Tinsley, J.R., Hurley, J.P., Trainham, R., Keegan, R.P.
Object Type: Article
System: The UNT Digital Library
Performance Contracting and Energy Efficiency in the State Government Market (open access)

Performance Contracting and Energy Efficiency in the State Government Market

There is growing interest in energy efficiency (EE) among state policymakers as a result of increasing environmental concerns, rising electricity and natural gas prices, and lean economic times that motivate states to look more aggressively for cost-saving opportunities in public sector buildings. One logical place for state policymakers to demonstrate their commitment to energy efficiency is to 'lead by example' by developing and implementing strategies to reduce the energy consumption of state government facilities through investments in energy efficient technologies. Traditionally, energy efficiency improvements at state government facilities are viewed as a subset in the general category of building maintenance and construction. These projects are typically funded through direct appropriations. However, energy efficiency projects are often delayed or reduced in scope whereby not all cost-effective measures are implemented because many states have tight capital budgets. Energy Savings Performance Contracting (ESPC) offers a potentially useful strategy for state program and facility managers to proactively finance and develop energy efficiency projects. In an ESPC project, Energy Service Companies (ESCOs) typically guarantee that the energy and cost savings produced by the project will equal or exceed all costs associated with implementing the project over the term of the contract. ESCOs typically provide turnkey …
Date: November 14, 2008
Creator: Bharvirkar, Ranjit; Goldman, Charles; Gilligan, Donald; Singer, Terry E.; Birr, David; Donahue, Patricia et al.
Object Type: Report
System: The UNT Digital Library
Problem Proposed for the American Mathematical Monthly (open access)

Problem Proposed for the American Mathematical Monthly

The problem is to define: P(x) := {Sigma}{sub k = 1}{sup {infinity}} arctan (x - 1/(k + x + 1) {radical}(k + 1) + (k + 2) {radical}(k + x)). (1) (a) Find explicit, finite-expression evaluations of P(n) for all integers n {ge} 0. (b) Show {tau} := lim{sub x {yields} -1{sup +}} P(x) exists, and find an explicit evaluation for {tau}. (c) Are there a more general closed forms for P, say at half-integers? Solution with the abbreviations: r := {radical} (k + 1), s := {radical} (k + x) the argument of arctan in (1) becomes s{sup 2} - r{sup 2}/(s{sup 2} + 1) r + (r{sup 2} + 1) s = s - r/r s + 1 = 1/r - 1/s / 1 + 1/r 1/s.
Date: November 14, 2008
Creator: Bailey, David H.; Borwein, Jonathan M. & Waldvogel, Jorg
Object Type: Article
System: The UNT Digital Library
Theoretical Treatment of the Thermophysical Properties of Fluids Containing Chain-like Molecules (open access)

Theoretical Treatment of the Thermophysical Properties of Fluids Containing Chain-like Molecules

This research program was designed to enhance our understanding of the behavior of fluids and fluid mixtures containing chain-like molecules. The original objective was to explain and predict the experimentally observed thermophysical properties, including phase equilibria and dynamics, of systems containing long flexible molecules ranging in length from alkanes to polymers. Over the years the objectives were expanded to include the treatment of molecules that were not chain-like. Molecular dynamics and Monte Carlo computer simulations were used to investigate how variations in molecular size, shape and architecture influence the types of phase equilibria, thermodynamic properties, structure and surface interactions that are observed experimentally. The molecular insights and theories resulting from this program could eventually serve as the foundation upon which to build correlations of the properties of fluids that are both directly and indirectly related to the Nation’s energy resources including: petroleum, natural gas, and polymer solutions, melts, blends, and materials.
Date: November 14, 2008
Creator: Hall, Carol K.
Object Type: Report
System: The UNT Digital Library
Active Damping of the E-P Instability at the LANL PSR (open access)

Active Damping of the E-P Instability at the LANL PSR

A prototype of an analog, transverse (vertical) feedback system for active damping of the two-stream (e-p) instability has been developed and successfully tested at the Los Alamos National Laboratory Proton Storage Ring (PSR). This system was able to improve the instability threshold by approximately 30% (as measured by the change in RF buncher voltage at instability threshold). Evidence obtained from these tests suggests that further improvement in performance is limited by beam leakage into the gap at lower RF buncher voltage and the onset of instability in the horizontal plane, which had no feedback. Here we describe the present system configuration, system optimization, results of several recent experimental tests, and results from studies of factors limiting its performance.
Date: November 14, 2007
Creator: McCrady, R.; Macek, R.J.; Zaugg, T.; Alamos, /Los; Assadi, S.; Deibele, C. et al.
Object Type: Article
System: The UNT Digital Library
AGN-Induced Cavities in NGC 1399 And NGC 4649 (open access)

AGN-Induced Cavities in NGC 1399 And NGC 4649

We present an analysis of archival Chandra and VLA observations of the E0 galaxy NGC1399 and the E2 galaxy NGC4649 in which we investigate cavities in the surrounding X-ray emitting medium caused by the central AGN. We calculate the jet power required for the AGN to evacuate these cavities and find values of {approx} 8x10{sup 41} erg s-1 and {approx} 14x10{sup 41} erg s{sup -1} for the lobes of NGC1399 and {approx} 7x10{sup 41} erg s{sup -1} and {approx} 6x1041 erg s{sup -1} for those of NGC4649. We also calculate the k/f values for each cavity, where k is the ratio of the total particle energy to that of electrons radiating in the range of 10 MHz to 10 GHz, and f is the volume filling factor of the plasma in the cavity. We find that the values of k/f for the lobes of NGC1399 are {approx} 93 and {approx} 190, and those of the lobes of NGC4649 are {approx} 15000 and {approx} 12000. We conclude that the assumed spectrum describes the electron distribution in the lobes of NGC1399 reasonably well, and that there are few entrained particles. For NGC4649, either there are many entrained particles or the model spectrum …
Date: November 14, 2007
Creator: Shurkin, K.; U., /New Mexico; Dunn, R. J. H.; U., /Southampton; Gentile, G.; Taylor, G. B. et al.
Object Type: Article
System: The UNT Digital Library

Air Cooling Technology for Power Electronics Thermal Control

Assessing potential for air cooling in power electronics is a critical factor in power electronics equipment. NREL aims to assess effective air cooling techniques for power electronics technologies.
Date: November 14, 2007
Creator: Bharathan, D.
Object Type: Presentation
System: The UNT Digital Library
Direct Observation of Cosmic Strings Via Their Strong Gravitational Lensing Effect. 1. Predictions for High Resolution Imaging Surveys (open access)

Direct Observation of Cosmic Strings Via Their Strong Gravitational Lensing Effect. 1. Predictions for High Resolution Imaging Surveys

We use current theoretical estimates for the density of long cosmic strings to predict the number of strong gravitational lensing events in astronomical imaging surveys as a function of angular resolution and survey area. We show that angular resolution is the single most important factor, and that interesting limits on the dimensionless string tension G{mu}/c{sup 2} can be obtained by existing and planned surveys. At the resolution of the Hubble Space Telescope (0'.14), it is sufficient to survey of order a square degree -- well within reach of the current HST archive -- to probe the regime G{mu}/c{sup 2} {approx} 10{sup -8}. If lensing by cosmic strings is not detected, such a survey would improve the limit on the string tension by an order of magnitude on that available from the cosmic microwave background. At the resolution (0'.028) attainable with the next generation of large ground based instruments, both in the radio and the infra-red with adaptive optics, surveying a sky area of order ten square degrees will allow us to probe the G{mu}/c{sup 2} {approx} 10{sup -9} regime. These limits will not be improved significantly by increasing the solid angle of the survey.
Date: November 14, 2007
Creator: Gasparini, Maria Alice; Marshall, Phil; Treu, Tommaso; /UC, Santa Barbara; Morganson, Eric; /KIPAC, Menlo Park et al.
Object Type: Article
System: The UNT Digital Library
Discovery of a Jupiter/Saturn Analog With Gravitational Microlensing (open access)

Discovery of a Jupiter/Saturn Analog With Gravitational Microlensing

Searches for extrasolar planets have uncovered an astonishing diversity of planetary systems, yet the frequency of solar system analogs remains unknown. The gravitational microlensing planet search method is potentially sensitive to multiple-planet systems containing analogs of all the solar system planets except Mercury. We report the first detection of a multiple-planet system with microlensing. We identify two planets with masses of {approx} 0.71 and {approx} 0.27 times the mass of Jupiter and orbital separations of {approx} 2.3 and {approx} 4.6 astronomical units orbiting a primary of mass {approx} 0.50 solar masses. This system resembles a scaled version of our solar system in that the mass ratio, separation ratio, and equilibrium temperatures of the planets are similar to those of Jupiter and Saturn. These planets could not have been detected with other techniques; their discovery from only 6 confirmed microlensing planet detections suggests that solar system analogs may be common.
Date: November 14, 2007
Creator: Gaudi, B. S.; Bennett, D. P.; Udalski, A.; Gould, A.; Christie, G. W.; Maoz, D. et al.
Object Type: Article
System: The UNT Digital Library
ELECTROCHEMICAL CORROSION TESTS FOR TANK 241-AY-101 CORE 325 SEGMENTS 16R1 & 16R2 (open access)

ELECTROCHEMICAL CORROSION TESTS FOR TANK 241-AY-101 CORE 325 SEGMENTS 16R1 & 16R2

The interstitial liquid in the double-shell tank 241-AY-101 settled solids layer is below the hydroxide chemistry control limit required by HNF-SD-WM-TSR-006, Tank Farms Technical Safety Requirements, Administrative Control 5.16, 'Corrosion Mitigation Controls'. Operating tanks outside of the specification may increase the propensity corrosion of the carbon steel wall. This report is concerned with generalized electrochemical corrosion mechanism that may occur at specific loci. All cyclic potentiodynamic polarization scans exhibited a negative hysteresis, scan reversing at lower current density, indicating that there was no pitting propensity. The general electrochemical corrosion rates ranged from 4.4E-02 to 1.5E-03 mpy with the first round of coupons, while the second round yielded corrosion rates of 2.5E-03 to 2.9E-02 mpy.
Date: November 14, 2007
Creator: JB, DUNCAN & RB, WYRWAS
Object Type: Report
System: The UNT Digital Library
Electron Cloud Generation And Trapping in a Quadrupole Magnet at the Los Alamos PSR (open access)

Electron Cloud Generation And Trapping in a Quadrupole Magnet at the Los Alamos PSR

A diagnostic to measure electron cloud formation and trapping in a quadrupole magnet has been developed, installed, and successfully tested at PSR. Beam studies with this diagnostic show that the electron flux striking the wall in the quadrupole is comparable to or larger than in an adjacent drift. In addition, the trapped electron signal, obtained using the sweeping feature of diagnostic, was larger than expected and decayed very slowly with an exponential time constant of 50 to 100 {micro}s. Experimental results were also obtained which suggest that a significant fraction of the electrons observed in the adjacent drift space were seeded by electrons ejected from the quadrupole.
Date: November 14, 2007
Creator: Macek, R. J.; Browman, A. A.; Ledford, J. E.; Borden, M. J.; O'Hara, J. F.; McCrady, R. C. et al.
Object Type: Article
System: The UNT Digital Library
EXAMPLE OF A RISK BASED DISPOSAL APPROVAL SOLIDIFICATION OF HANFORD SITE TRANSURANIC (TRU) WASTE (open access)

EXAMPLE OF A RISK BASED DISPOSAL APPROVAL SOLIDIFICATION OF HANFORD SITE TRANSURANIC (TRU) WASTE

The Hanford Site requested, and the U.S. Environmental Protection Agency (EPA) Region 10 approved, a Toxic Substances Control Act of 1976 (TSCA) risk-based disposal approval (RBDA) for solidifying approximately four cubic meters of waste from a specific area of one of the K East Basin: the North Loadout Pit (NLOP). The NLOP waste is a highly radioactive sludge that contained polychlorinated biphenyls (PCBs) regulated under TSCA. The prescribed disposal method for liquid PCB waste under TSCA regulations is either thermal treatment or decontamination. Due to the radioactive nature of the waste, however, neither thermal treatment nor decontamination was a viable option. As a result, the proposed treatment consisted of solidifying the material to comply with waste acceptance criteria at the Waste Isolation Pilot Plant (WPP) in Carlsbad, New Mexico, or possibly the Environmental Restoration Disposal Facility at the Hanford Site, depending on the resulting transuranic (TRU) content of the stabilized waste. The RBDA evaluated environmental risks associated with potential airborne PCBs. In addition, the RBDA made use of waste management controls already in place at the treatment unit. The treatment unit, the T Plant Complex, is a Resource Conservation and Recovery Act of 1976 (RCRA)-permitted facility used for storing and …
Date: November 14, 2007
Creator: AL, PRIGNANO
Object Type: Article
System: The UNT Digital Library
Experiments to Understand HPC Time to Development (Final report for Department of Energy contract DE-FG02-04ER25633) Report DOE/ER/25633-1 (open access)

Experiments to Understand HPC Time to Development (Final report for Department of Energy contract DE-FG02-04ER25633) Report DOE/ER/25633-1

In order to understand how high performance computing (HPC) programs are developed, a series of experiments, using students in graduate level HPC classes and various research centers, were conducted at various locations in the US. In this report, we discuss this research, give some of the early results of those experiments, and describe a web-based Experiment Manager we are developing that allows us to run studies more easily and consistently at universities and laboratories, allowing us to generate results that more accurately reflect the process of building HPC programs.
Date: November 14, 2007
Creator: Basili, Victor, R. & Zelkowitz, Marvin, V.
Object Type: Report
System: The UNT Digital Library
Final-State Interactions and Single-Spin Asymmetries in Semi-inclusive Deep Inelastic Scattering (open access)

Final-State Interactions and Single-Spin Asymmetries in Semi-inclusive Deep Inelastic Scattering

Recent measurements from the HERMES and SMC collaborations show a remarkably large azimuthal single-spin asymmetries A{sub UL} and A{sub UT} of the proton in semi-inclusive pion leptoproduction {gamma}*(q)p {yields} {pi}X. We show that final-state interactions from gluon exchange between the outgoing quark and the target spectator system leads to single-spin asymmetries in deep inelastic lepton-proton scattering at leading twist in perturbative QCD; i.e., the rescattering corrections are not power-law suppressed at large photon virtuality q{sup 2} at fixed x{sub bj}. The existence of such single-spin asymmetries requires a phase difference between two amplitudes coupling the proton target with J{sup z}{sub p} = {+-}1/2 to the same final-state, the same amplitudes which are necessary to produce a nonzero proton anomalous magnetic moment. We show that the exchange of gauge particles between the outgoing quark and the proton spectators produces a Coulomb-like complex phase which depends on the angular momentum L{sup z} of the proton's constituents and thus is distinct for different proton spin amplitudes. The single-spin asymmetry which arises from such final-state interactions does not factorize into a product of structure function and fragmentation function, and it is not related to the transversity distribution {delta}q(x;Q) which correlates transversely polarized quarks with …
Date: November 14, 2007
Creator: Brodsky, Stanley J.; Hwang, Dae Sung & Schmidt, Ivan
Object Type: Article
System: The UNT Digital Library
HESS J1023-575: Non-Thermal Particle Acceleration Associated With the Young Stellar Cluster Westerlund 2 (open access)

HESS J1023-575: Non-Thermal Particle Acceleration Associated With the Young Stellar Cluster Westerlund 2

The results from H.E.S.S. observations towards Westerlund 2 are presented. The detection of very-high-energy gamma-ray emission towards the young stellar cluster Westerlund 2 in the HII complex RCW49 by H.E.S.S. provides ample evidence that particle acceleration to extreme energies is associated with this region. A variety of possible emission scenarios is mentioned, ranging from high-energy gamma-ray production in the colliding wind zone of the massive Wolf-Rayet binary WR 20a, collective wind scenarios, diffusive shock acceleration at the boundaries of wind-blown bubbles in the stellar cluster, and outbreak phenomena from hot stellar winds into the interstellar medium. These scenarios are briefly compared to the characteristics of the associated new VHE gamma-ray source HESS J1023-575, and conclusions on the validity of the respective emission scenarios for high-energy gamma-ray production in the Westerlund 2 system are drawn.
Date: November 14, 2007
Creator: Reimer, O.; /Stanford U., HEPL /KIPAC, Menlo Park; Hinton, J.; U., /Leeds; Hofmann, W.; Hoppe, S. et al.
Object Type: Article
System: The UNT Digital Library
IMPROVEMENTS IN CONTAINER MANAGEMENT OF TRANSURANIC (TRU) AND LOW LEVEL RADIOACTIVE WASTE STORED AT THE CENTRAL WASTE COMPLEX (CWC) AT HANFORD (open access)

IMPROVEMENTS IN CONTAINER MANAGEMENT OF TRANSURANIC (TRU) AND LOW LEVEL RADIOACTIVE WASTE STORED AT THE CENTRAL WASTE COMPLEX (CWC) AT HANFORD

The Central Waste Complex (CWC) is the interim storage facility for Resource Conservation & Recovery Act (RCRA) mixed waste, transuranic waste, transuranic mixed waste, low-level and low-level mixed radioactive waste at the Department of Energy's (DOE'S) Hanford Site. The majority of the waste stored at the facility is retrieved from the low-level burial grounds in the 200 West Area at the Site, with minor quantities of newly generated waste from on-site and off-site waste generators. The CWC comprises 18 storage buildings that house 13,000 containers. Each waste container within the facility is scanned into its location by building, module, tier and position and the information is stored in a site-wide database. As waste is retrieved from the burial grounds, a preliminary non-destructive assay is performed to determine if the waste is transuranic (TRU) or low-level waste (LLW) and subsequently shipped to the CWC. In general, the TRU and LLW waste containers are stored in separate locations within the CWC, but the final disposition of each waste container is not known upon receipt. The final disposition of each waste container is determined by the appropriate program as process knowledge is applied and characterization data becomes available. Waste containers are stored within …
Date: November 14, 2007
Creator: Uytioco, E. M.
Object Type: Article
System: The UNT Digital Library
In –Situ Spectroscopic Investigation of Immobilized Organometallic Catalysts (open access)

In –Situ Spectroscopic Investigation of Immobilized Organometallic Catalysts

Immobilized organometallic catalysts, in principle, can give high rates and selectivities like homogeneous catalysts with the ease of separation enjoyed by heterogeneous catalysts. However, the science of immobilized organometallics has not been developed because the field lies at the interface between the homogeneous and heterogeneous catalysis communities. By assembling an interdisciplinary research team that can probe all aspects of immobilized organometallic catalyst design, the entire reacting system can be considered, where the transition metal complex, the complex-support interface and the properties of the support can all be considered simultaneously from both experimental and theoretical points of view. Researchers at Georgia Tech and the University of Virginia are studying the fundamental principles that can be used to understand and design future classes of immobilized organometallic catalysts. In the framework of the overall collaborative project with Georgia Tech, our work focused on (a) the X-ray absorption spectroscopy of an immobilized Pd-SCS-O complex (b) the mode of metal leaching from supported Pd catalysts during Heck catalysis and (c) the mode of deactivation of Jacobsen’s Co-salen catalysts during the hydrolytic kinetic resolution of terminal epoxides. Catalysts containing supported Pd pincer complexes, functionalized supports containing mercapto and amine groups, and oligomeric Co-salen catalysts were synthesized …
Date: November 14, 2007
Creator: Davis, Robert, J.
Object Type: Report
System: The UNT Digital Library