Serial/Series Title
Proceedings of the Workshop on Geothermal Reservoir Engineering
11
Fiscal Year 2000
3
Carbon Sequestration on Surface Mine Lands Quarterly Report
2
Downhole Power Generation and Wireless Communications for Intelligent Completions Applications, Quarterly Report
2
Federal Emergency Management Information System (FEMIS)
2
Fiscal Year 1990
2
Fiscal Year 1999
2
Fiscal Year 2001
2
Improved Miscible Nitrogen Flood Performance Utilizing Advanced Reservoir Characterization and Horizontal Laterals in a Class I Reservoir - East Binger (Marchand) Unit Quarterly Report
2
Low-Cost Solar Array Project
2
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Experimental and Numerical Investigation of Flows in Expanding Channels
We present an experimental realization of the classical Jeffery-Hamel flows inside a wedge-shaped channel. We compare the measured velocity fields with the predictions of Jeffery-Hamel theory. A detailed experimental study of bifurcation diagrams for the solutions reveals the absolute stability of the pure outflow solution and an interesting hysteretic structure for bifurcations. We also observe a multiple vortex flow regime predicted earlier numerically and analytically. Experimental studies of the stability of the flow to perturbations at the channel exit are also conducted.
Date:
October 24, 2008
Creator:
Vorobieff, Peter & Putkaradze, Vakhtang
Object Type:
Report
System:
The UNT Digital Library
Measurement of the tau- to eta pi-pi+pi-nu tau Branching Fraction and a Search for a Second-Class Current in the tau- to eta'(958)pi-nu tau Decay
The {tau}{sup -} {yields} {eta}{pi}{sup -}{pi}{sup +}{pi}{sup -}{nu}{sub {tau}} decay with the {eta} {yields} {gamma}{gamma} mode is studied using 384 fb{sup -1} of data collected by the BABAR detector. The branching fraction is measured to be (1.60 {+-} 0.05 {+-} 0.11) x 10{sup -4}. It is found that {tau}{sup -} {yields} f{sub 1}(1285){pi}{sup -} {nu}{sub {tau}} {yields} {eta}{pi}{sup -}{pi}{sup +}{pi}{sup -}{nu}{sub {tau}} is the dominant decay mode with a branching fraction of (1.11 {+-} 0.06 {+-} 0.05) x 10{sup -4}. The first error on the branching fractions is statistical and the second systematic. In addition, a 90% confidence level upper limit on the branching fraction of the {tau}{sup -} {yields} {eta}{prime}(958){pi}{sup -}{nu}{sub {tau}} decay is measured to be 7.2 x 10{sup -6}. This last decay proceeds through a second-class current and is expected to be forbidden in the limit of isospin symmetry.
Date:
March 24, 2008
Creator:
Aubert, B.; Bona, M.; Boutigny, D.; Karyotakis, Y.; Lees, J. P.; Poireau, V. et al.
Object Type:
Article
System:
The UNT Digital Library
Remaining Sites Verification Package for the 100-F-31, 144-F Sanitary Sewer System, Waste Site Reclassification Form 2006-033
The 100-F-31 waste site is a former septic system that supported the inhalation laboratories, also referred to as the 144-F Particle Exposure Laboratory (132-F-2 waste site), which housed animals exposed to particulate material. The 100-F-31 waste site has been remediated to achieve the remedial action objectives specified in the Remaining Sites ROD. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.
Date:
August 24, 2006
Creator:
Dittmer, L. M.
Object Type:
Report
System:
The UNT Digital Library
The impact of retail rate structures on the economics of commercial photovoltaic systems in California
This article examines the impact of retail electricity rate design on the economic value of grid-connected photovoltaic (PV) systems, focusing on commercial customers in California. Using 15-min interval building load and PV production data from a sample of 24 actual commercial PV installations, we compare the value of the bill savings across 20 commercial-customer retail electricity rates currently offered in the state. Across all combinations of customers and rates, we find that the annual bill savings from PV, per kWh generated, ranges from $0.05 to $0.24/kWh. This sizable range in rate-reduction value reflects differences in rate structures, revenue requirements, the size of the PV system relative to building load, and customer load shape. The most significant rate design issue for the value of commercial PV is found to be the percentage of total utility bills recovered through demand charges, though a variety of other factors are also found to be of importance. The value of net metering is found to be substantial, but only when energy from commercial PV systems represents a sizable portion of annual customer load. Though the analysis presented here is specific to California, our general results demonstrate the fundamental importance of retail rate design for the …
Date:
June 24, 2008
Creator:
Mills, Andrew D.; Wiser, Ryan; Barbose, Galen & Golove, William
Object Type:
Article
System:
The UNT Digital Library
Arroyo Mocho Boulder Removal Project: Lawrence Livermore National Laboratory Hetch Hetchy Pump Station
None
Date:
July 24, 2007
Creator:
Burkholder, L; Kato, T & van Hattem, M
Object Type:
Report
System:
The UNT Digital Library
Can cross sections be accurately known for priori?
Distinct maxima and minima in the neutron total cross section uncertainties were observed in our large scale covariance calculations using a spherical optical potential. In this contribution we investigate the physical origin of this oscillating structure. Specifically, we analyze the case of neutron reactions on {sup 56}Fe, for which total cross section uncertainties are characterized by the presence of five distinct minima at 0.1, 1.1, 5, 25, and 70 MeV. To investigate their origin, we calculated total cross sections by perturbing the real volume depth V{sub v} by its expected uncertainty {+-}{Delta}V{sub v}. Inspecting the effect of this perturbation on the partial wave cross sections we found that the first minimum (at 0.1 MeV) is exclusively due to the contribution of the s-wave. On the other hand, the same analysis at 1.1 MeV showed that the minimum is the result of the interplay between s-, p-, and d-waves; namely the change in the s-wave happens to be counterbalanced by changes in the p- and d-waves. Similar considerations can be extended for the third minimum, although it can be also explained in terms of the Ramsauer effect as well as the other ones (at 25 and 70 MeV). We discuss the …
Date:
June 24, 2008
Creator:
Pigni, M. T.; Dietrich, F. S.; Herman, M. & Oblozinsky, P.
Object Type:
Article
System:
The UNT Digital Library
Depth-resolved soft x-ray photoelectron emission microscopy in nanostructures via standing-wave excited photoemission
We present an extension of conventional laterally resolved soft x-ray photoelectron emission microscopy. A depth resolution along the surface normal down to a few {angstrom} can be achieved by setting up standing x-ray wave fields in a multilayer substrate. The sample is an Ag/Co/Au trilayer, whose first layer has a wedge profile, grown on a Si/MoSi2 multilayer mirror. Tuning the incident x-ray to the mirror Bragg angle we set up standing x-ray wave fields. We demonstrate the resulting depth resolution by imaging the standing wave fields as they move through the trilayer wedge structure.
Date:
November 24, 2008
Creator:
Kronast, F.; Ovsyannikov, R.; Kaiser, A.; Wiemann, C.; Yang, S. -H.; Locatelli, A. et al.
Object Type:
Article
System:
The UNT Digital Library
Transient Analyses for the Uzbekistan VVR-SM Reactor with IRT-3M HEU Fuel and IRT-4M LEU fuel : ANL Independent Verification Results.
Calculations have been performed for postulated transients in the VVR-SM Reactor at the Institute of Nuclear Physics (INP) of the Academy of Sciences in the Republic of Uzbekistan. (The reactor designation in Cyrillic is BBP-CM; transliterating characters to English gives VVRSM but translating words gives WWR-SM.) These calculations have been performed at the request of staff of the INP who are performing similar calculations. The transients considered were established during working meetings between Argonne National Laboratory (ANL) and INP staff during summer 2006 [Ref. 1], subsequent email correspondence, and subsequent staff visits. Calculations were performed for the current high-enriched uranium (HEU) core, the proposed low-enriched uranium (LEU) core, and one mixed HEU-LEU core during the transition. These calculations have been performed independently from those being performed by INP and serve as one step in the verification process.
Date:
September 24, 2007
Creator:
Garner, P. L. & Hanan, N. A.
Object Type:
Report
System:
The UNT Digital Library
Center for Programming Models for Scalable Parallel Computing: Future Programming Models
The mission of the pmodel center project is to develop software technology to support scalable parallel programming models for terascale systems. The goal of the specific UD subproject is in the context developing an efficient and robust methodology and tools for HPC programming. More specifically, the focus is on developing new programming models which facilitate programmers in porting their application onto parallel high performance computing systems. During the course of the research in the past 5 years, the landscape of microprocessor chip architecture has witnessed a fundamental change – the emergence of multi-core/many-core chip architecture appear to become the mainstream technology and will have a major impact to for future generation parallel machines. The programming model for shared-address space machines is becoming critical to such multi-core architectures. Our research highlight is the in-depth study of proposed fine-grain parallelism/multithreading support on such future generation multi-core architectures. Our research has demonstrated the significant impact such fine-grain multithreading model can have on the productivity of parallel programming models and their efficient implementation.
Date:
July 24, 2008
Creator:
Gao, Guang, R.
Object Type:
Report
System:
The UNT Digital Library
Energy dependence of jet transport parameter and parton saturationin quark-gluon plasma
We study the evolution and saturation of the gluondistribution function in the quark-gluon plasma as probed by apropagating parton and its effect on the computation of jet quenching ortransport parameter $\hat q $. For thermal partons, the saturation scale$Q2_s$ is found to be proportional to the Debye screening mass $\mu_D2$.For hard probes, evolution at small $x=Q2_s/6ET$ leads to jet energydependence of hat q. We study this dependence for both a conformal gaugetheory in weak and strong coupling limit and for (pure gluon) QCD. Theenergy dependence can be used to extract the shear viscosity $\eta$ ofthe medium since $\eta$ can be related to the transport parameter forthermal partons in a transport description. We also derive upper boundson the transport parameter for both energetic and thermal partons. Thelater leads to a lower bound on shear viscosity-to-entropy density ratiowhich is consistent with the conjectured lower bound $\eta/s\geq 1/4\pi$.Implications on the study of jet quenching at RHIC and LHC and the bulkproperties of the dense matter are discussed.
Date:
June 24, 2007
Creator:
Casalderrey-Solana, Jorge & Wang, Xin-Nian
Object Type:
Article
System:
The UNT Digital Library
Evaluation of near field rock treatment during constructions (LADSfeature #22)
The purpose of this report is to evaluate the effect of near-field rock treatment by injection of reactive material (calcite) above the drift for the purpose of decreasing postclosure drift seepage. The method used for the calculation was a coupled reaction-transport numerical model for gas-water-rock interaction. This includes the mass conservation of heat, liquid and gas for thermohydrological calculations, of aqueous and gaseous species for advective and diffusive transport, and the kinetics of mineral-water reactions.
Date:
November 24, 1998
Creator:
Sonnenthal, Eric & Spycher, Nicolas
Object Type:
Report
System:
The UNT Digital Library
Measurement of electron clouds in large accelerators by microwave dispersion
Clouds of low energy electrons in the vacuum beam pipes of accelerators of positively charged particle beams present a serious limitation for operation at high currents. Furthermore, it is difficult to probe their density over substantial lengths of the beam pipe. We have developed a novel technique to directly measure the electron cloud density via the phase shift induced in a TE wave transmitted over a section of the accelerator and used it to measure the average electron cloud density over a 50 m section in the positron ring of the PEP-II collider at the Stanford Linear Accelerator Center.
Date:
January 24, 2008
Creator:
Desantis, Stefano; De Santis, Stefano; Byrd, John M.; Sonnad, Kiran G.; Pivi, Mauro T.F.; Krasnykh, Anatoly et al.
Object Type:
Article
System:
The UNT Digital Library
Analyses of Oxyanion Materials by Prompt Gamma Activation Analysis
Prompt gamma activation analysis (PGAA) has been used to analyze metal ion oxyanion materials that have multiple applications, including medicine, materials, catalysts, and electronics. The significance for the need for accurate, highly sensitive analyses for the materials is discussed in the context of quality control of end products containing the parent element in each material. Applications of the analytical data for input to models and theoretical calculations related to the electronic and other properties of the materials are discussed.
Date:
March 24, 2008
Creator:
Firestone, Richard B.; Perry, D. L.; English, G. A.; Firestone, R. B.; Leung, K. N.; Garabedian, G. et al.
Object Type:
Article
System:
The UNT Digital Library
Experimental Tests of Cooling: Expectations and Additional Needs
Cooling is a critical aspect for a high-performance Neutrino Factory or a MuonCollider. For this reason, considerable effort is being put toward theexperimental verification of this technique. The international Muon IonizationCooling Experiment, MICE, was approved to operate at Rutherford AppletonLaboratory (RAL) in the UK and beam line commissioning commenced in March, 2008. The MICE collaboration comprises about 130 scientists and engineers from Asia, Europe, and the U.S. In this paper we present the motivation and goals for thisexperiment and describe its present status. MICE is scheduled for completion in2011. We will also indicate the prospects for a future 6D muon coolingexperiment and discuss its possible time schedule.
Date:
September 24, 2008
Creator:
Zisman, Michael S
Object Type:
Article
System:
The UNT Digital Library
Surface Geophysical Exploration of Tx-Ty Tank Farms at the Hanford Site: Results of Background Characterization With Ground Penetrating Radar
Ground penetrating radar surveys of the TX and TY tank farms were performed to identify existing infrastructure in the near surface environment. These surveys were designed to provide background information supporting Surface-to-Surface and Well-to-Well resistivity surveys of Waste Management Area TX-TY. The objective of the preliminary investigation was to collect background characterization information with GPR to understand the spatial distribution of metallic objects that could potentially interfere with the results from high resolution resistivity{trademark} surveys. The results of the background characterization confirm the existence of documented infrastructure, as well as highlight locations of possible additional undocumented subsurface metallic objects.
Date:
July 24, 2008
Creator:
Cubbage, B.; Brauchla, R.; O'Brien, G. & Bergeron, M.
Object Type:
Report
System:
The UNT Digital Library
Development of a Multi Megawatt Circulator for X Band
Research is in progress on a TeV-scale linear collider that will operate at 5-10 times the energy of present-generation accelerators. This will require development of high power RF sources generating of 50-100 MW per source. Transmission of power at this level requires overmoded waveguide to avoid breakdown. In particular, the TE{sub 01} circular waveguide mode is currently the mode of choice for waveguide transmission at Stanford Linear Accelerator Center (SLAC) in the Multimode Delay Line Distribution System (MDLDS). A common device for protecting an RF source from reflected power is the waveguide circulator. A circulator is typically a three-port device that allows low loss power transmission from the source to the load, but diverts power coming from the load (reflected power) to a third terminated port. To achieve a low loss, matched, three port junction requires nonreciprocal behavior. This is achieved using ferrites in a static magnetic field which introduces a propagation constant dependent on RF field direction relative to the static magnetic field. Circulators are currently available at X-Band for power levels up to 1 MW in fundamental rectangular waveguide; however, the next generation of RF sources for TeV-level accelerators will require circulators in the 50-100 MW range. Clearly, …
Date:
March 24, 2008
Creator:
Neilson, J.; Ives, L. & Tantawi, S. G.
Object Type:
Article
System:
The UNT Digital Library
Testing Large CICC in Short Sample Configuration and Predicting Their Performance in Large Magnets
It is well known that large Nb3Sn Cable-in-Conduit Conductors (CICC) do not always completely utilize current carrying capacity of the strands they are made of. The modern state of theory is not accurate enough to eliminate CICC full scale testing. Measuring properties of large CICC is not a simple task due to variety of parameters that need to be controlled, like temperature, exposure of all the strands to the peak magnetic field, mass flow and particular nonuniform current distribution. The paper presents some measurement issues of CICC testing in a short sample test facility, particularly, conditions for uniform current distribution and effect of twist pitches on the critical current.
Date:
August 24, 2007
Creator:
Martovetsky, N. N.
Object Type:
Article
System:
The UNT Digital Library
The dihadron fragmentation function and its evolution
Dihadron fragmentation functions and their evolution arestudied in the process of e+e- annihilation. Under the collinearfactorization approximation and facilitated by the cut-vertex technique,the two hadron inclusive cross section at leading order (LO) is shown tofactorize into a short distance parton cross section and a long distancedihadron fragmentation function. We provide the definition of such adihadron fragmentation function in terms of parton matrix elements andderive its DGLAP evolution equation at leading log. The evolutionequation for the non-singlet quark fragmentation function is solvednumerically with a simple ansatz for the initial condition and resultsare presented for cases of physical interest.
Date:
February 24, 2004
Creator:
Majumder, Abhijit & Wang, Xin-Nian
Object Type:
Article
System:
The UNT Digital Library
A Search for Neutrinoless Tau Decays to Three Leptons
Using approximately 350 million {tau}{sup +}{tau}{sup -} pair events recorded with the BaBar detector at the Stanford Linear Accelerator Center between 1999 and 2006, a search has been made for neutrinoless, lepton-flavor violating tau decays to three lighter leptons. All six decay modes consistent with conservation of electric charge and energy have been considered. With signal selection efficiencies of 5-12%, we obtain 90% confidence level upper limits on the branching fraction {Beta}({tau} {yields} {ell}{ell}{ell}) in the range (4-8) x 10{sup -8}.
Date:
September 24, 2008
Creator:
Kolb, Jeffrey A. & /SLAC, /Oregon U.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Science & Technology Review December 2007
This month's issue has the following articles: (1) Homeland Security Begins Abroad--Commentary by John C. Doesburg; (2) Out of Harm's Way--New physical protection and accountability systems, together with a focus on security, safeguard nuclear materials in the Russian Federation; (3) A Calculated Journey to the Center of the Earth--Determining the permeability of partially melted metals in a mineral matrix unlocks secrets about the formation of Earth's core; (4) Wireless That Works--Communication technologies using ultrawideband radar are improving national security; and (5) Power to the People--Edward Teller envisioned safe and plentiful nuclear power for peaceful applications.
Date:
October 24, 2007
Creator:
Chinn, D. J.
Object Type:
Report
System:
The UNT Digital Library
Vacuum-Ultraviolet (VUV) Photoionization of Small Methanol and Methanol-Water Clusters
In this work, we report on the vacuum-ultraviolet (VUV) photoionization of small methanol and methanol-water clusters. Clusters of methanol with water are generated via co-expansion of the gas phase constituents in a continuous supersonic jet expansion of methanol and water seeded in Ar. The resulting clusters are investigated by single photon ionization with tunable vacuum-ultraviolet synchrotron radiation and mass analyzed using reflectron mass spectrometry. Protonated methanol clusters of the form (CH3OH)nH+(n = 1-12) dominate the mass spectrum below the ionization energy of the methanol monomer. With an increase in water concentration, small amounts of mixed clusters of the form (CH3OH n(H2O)H+ (n = 2-11) are detected. The only unprotonated species observed in this work are the methanol monomer and dimer. Appearance energies are obtained from the photoionization efficiency (PIE) curves for CH3OH+, (CH3OH)2+, (CH3OH)nH+ (n = 1-9), and (CH3OH)n(H2O)H+ (n = 2-9) as a function of photon energy. With an increasein the water content in the molecular beam, there is an enhancement of photoionization intensity for the methanol dimer and protonated methanol monomer at threshold. These results are compared and contrasted to previous experimental observations.
Date:
April 24, 2008
Creator:
Kostko, Oleg; Belau, Leonid; Wilson, Kevin R. & Ahmed, Musahid
Object Type:
Article
System:
The UNT Digital Library
Quantitative comparison between Type Ia supernova spectra at low and high redshifts: A case study
We develop a method to measure the strength of the absorption features in type Ia supernova (SN Ia) spectra and use it to make a quantitative comparisons between the spectra of type Ia supernovae at low and high redshifts. In this case study, we apply the method to 12 high-redshift (0.212 = z = 0.912) SNe Ia observed by the Supernova Cosmology Project. Through measurements of the strengths of these features and of the blueshift of theabsorption minimum in Ca ii H&K, we show that the spectra of the high-redshift SNe Ia are quantitatively similar to spectra of nearby SNe Ia (z< 0.15). One supernova in our high redshift sample, SN 2002fd at z = 0.279, is found to have spectral characteristics that are associated with peculiar SN 1991T/SN 1999aa-like supernovae.
Date:
March 24, 2008
Creator:
Supernova Cosmology Project
Object Type:
Article
System:
The UNT Digital Library
2006 Nevada Test Site Annual Illness and Injury Surveillance Report
The U.S. Department of Energy’s (DOE) commitment to assuring the health and safety of its workers includes the conduct of illness and injury surveillance activities that provide an early warning system to detect health problems among workers. The Illness and Injury Surveillance Program monitors illnesses and health conditions that result in an absence, occupational injuries and illnesses, and disabilities and deaths among current workers.
Date:
April 24, 2008
Creator:
United States. Department of Energy. Office of Health, Safety, and Security.
Object Type:
Report
System:
The UNT Digital Library
Femtosecond Time-Delay X-Ray Holography
X-ray free-electron lasers (XFELs) will produce photon pulses with a unique and desirable combination of properties. Their short X-ray wavelengths allow penetration into materials and the ability to probe structure at and below the nanometer scale. Their ultra-short duration gives information about this structure at the fundamental time-scales of atoms and molecules. The extreme intensity of the pulses will allow this information to be acquired in a single shot, so that these studies can be carried out on non-repeatable processes or on weakly-scattering objects that will be modified by the pulse. A fourth property of XFEL pulses is their high transverse coherence, which brings the promise of decades of innovation in visible optics to the X-ray regime, such as holography, interferometry, and laser-based imaging. Making an effective use of XFEL pulses, however, will benefit from innovations that are new to both X-ray science and coherent optics. One such innovation is the new method of time-delay X-ray holography [1], recently demonstrated at the FLASH FEL at DESY in Hamburg, to measure the evolution of objects irradiated by intense pulses. One of the pressing questions about the high-resolution XFEL imaging and characterization of non-periodic or weakly-scattering objects is the effect of the …
Date:
October 24, 2007
Creator:
Chapman, H N
Object Type:
Report
System:
The UNT Digital Library