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The transfer of neutral molecules, ions and ionic species from water to benzonitrile; comparison with nitrobenzene (open access)

The transfer of neutral molecules, ions and ionic species from water to benzonitrile; comparison with nitrobenzene

Article on the transfer of neutral molecules, ions and ionic species from water to benzonitrile and a comparison with nitrobenzene.
Date: October 15, 2011
Creator: Acree, William E. (William Eugene) & Abraham, M. H. (Michael H.)
System: The UNT Digital Library
Centrality and pseudorapidity dependence of charged hadron production at intermediate p{sub T} in Au+Au collisions at {radical}s{sub NN} = 130 GeV (open access)

Centrality and pseudorapidity dependence of charged hadron production at intermediate p{sub T} in Au+Au collisions at {radical}s{sub NN} = 130 GeV

We present STAR measurements of charged hadron production as a function of centrality in Au + Au collisions at {radical}s{sub NN} = 130 GeV. The measurements cover a phase space region of 0.2 < p{sub T} < 6.0 GeV/c in transverse momentum and -1 < {eta} < 1 in pseudorapidity. Inclusive transverse momentum distributions of charged hadrons in the pseudorapidity region 0.5 < |{eta}| < 1 are reported and compared to our previously published results for |{eta}| < 0.5. No significant difference is seen for inclusive p{sub T} distributions of charged hadrons in these two pseudorapidity bins. We measured dN/d{eta} distributions and truncated mean p{sub T} in a region of p{sub T} > p{sub T}{sup cut}, and studied the results in the framework of participant and binary scaling. No clear evidence is observed for participant scaling of charged hadron yield in the measured p{sub T} region. The relative importance of hard scattering process is investigated through binary scaling fraction of particle production.
Date: April 15, 2004
Creator: Adams, J.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D.; Arkhipkin, D. et al.
System: The UNT Digital Library
Centrality and pseudorapidity dependence of charged hadron production at intermediate p{sub t} in Au+Au collisions at {radical}s{sub NN} = 130 GeV (open access)

Centrality and pseudorapidity dependence of charged hadron production at intermediate p{sub t} in Au+Au collisions at {radical}s{sub NN} = 130 GeV

We present STAR measurements of charged hadron production as a function of centrality in Au + Au collisions at {radical}s{sub NN} = 130 GeV. The measurements cover a phase space region of 0.2 < p{sub T} < 6.0 GeV/c in transverse momentum and 11 < {eta} < 1 in pseudorapidity. Inclusive transverse momentum distributions of charged hadrons in the pseudorapidity region 0.5 < |{eta}| < 1 are reported and compared to our previously published results for |{eta}| < 0.5. No significant difference is seen for inclusive p{sub T} distributions of charged hadrons in these two pseudorapidity bins. We measured dN/d{eta} distributions and truncated mean p{sub T} in a region of p{sub T} > P{sub T}{sup cut}, and studied the results in the framework of participant and binary scaling. No clear evidence is observed for participant scaling of charged hadron yield in the measured pT region. The relative importance of hard scattering process is investigated through binary scaling fraction of particle production.
Date: April 15, 2004
Creator: Adams, J.; Aggarwal, M.M.; Ahammed, Z.; Amonett, J.; Anderson, B. D.; Arkhipkin, D. et al.
System: The UNT Digital Library
Advancing Reverse Electrowetting-on-Dielectric from Planar to Rough Surface Electrodes for High Power Density Energy Harvesting (open access)

Advancing Reverse Electrowetting-on-Dielectric from Planar to Rough Surface Electrodes for High Power Density Energy Harvesting

Article presenting electrical and multiphysics-based modeling approaches of REWOD energy harvester using structured rough surface electrodes. By enhancing the overall available surface area, an increase in the overall capacitance is achieved.
Date: December 15, 2021
Creator: Adhikari, Pashupati R.; Patwary, Adnan B.; Kakaraparty, Karthik; Gunti, Avinash; Reid, Russell C. & Mahbub, Ifana
System: The UNT Digital Library
Magnetic correlations in doped transition metal oxides (open access)

Magnetic correlations in doped transition metal oxides

The authors review recent reactor- and spallation-source-based neutron scattering experiments on the magnetic fluctuations and order in a variety of doped transition metal oxides. In particular, data are shown for the NiO chain compound, Y{sub 2{minus}x}Ca{sub x}BaNiO{sub 5}, the two-dimensional cuprate superconductors La{sub 2{minus}x}Sr{sub x}CuO{sub 4} and YBa{sub 2}Cu{sub 3} O{sub 6+x}, and the classical three-dimensional ``Mott-Hubbard`` system V{sub 2{minus}y}O{sub 3}.
Date: February 15, 1995
Creator: Aeppli, G.; Bao, W. & Broholm, C.
System: The UNT Digital Library
Deletion of ultraconserved elements yields viable mice (open access)

Deletion of ultraconserved elements yields viable mice

Ultraconserved elements have been suggested to retainextended perfect sequence identity between the human, mouse, and ratgenomes due to essential functional properties. To investigate thenecessities of these elements in vivo, we removed four non-codingultraconserved elements (ranging in length from 222 to 731 base pairs)from the mouse genome. To maximize the likelihood of observing aphenotype, we chose to delete elements that function as enhancers in amouse transgenic assay and that are near genes that exhibit markedphenotypes both when completely inactivated in the mouse as well as whentheir expression is altered due to other genomic modifications.Remarkably, all four resulting lines of mice lacking these ultraconservedelements were viable and fertile, and failed to reveal any criticalabnormalities when assayed for a variety of phenotypes including growth,longevity, pathology and metabolism. In addition more targeted screens,informed by the abnormalities observed in mice where genes in proximityto the investigated elements had been altered, also failed to revealnotable abnormalities. These results, while not inclusive of all thepossible phenotypic impact of the deleted sequences, indicate thatextreme sequence constraint does not necessarily reflect crucialfunctions required for viability.
Date: July 15, 2007
Creator: Ahituv, Nadav; Zhu, Yiwen; Visel, Axel; Holt, Amy; Afzal, Veena; Pennacchio, Len A. et al.
System: The UNT Digital Library
The Adiabatic Matching Section Solution for the Source Injector (open access)

The Adiabatic Matching Section Solution for the Source Injector

Typical designs for a Heavy Ion Fusion Power Plant require the source injector to deliver 100 beams, packed into an array with a spacing of 7 cm. When designing source injectors using a single large aperture source for each beam, the emitter surfaces are packed into an array with a spacing of 30 cm. Thus, the matching section of the source injector must not only prepare the beam for transport in a FODO lattice, but also funnel the beams together. This can be accomplished by an ESQ matching section in which each beam travels on average at a slight angle to the axis of the quadrupoles and uses the focusing effect of the FODO lattice to maintain the angle. At the end of the matching section, doublet steering is used to bring the beams parallel to each other for injection into the main accelerator. A specific solution of this type for an 84-beam source injector is presented. PACS: 41.75.Ak,41.85.Ar, 41.85.Ja
Date: September 15, 2000
Creator: Ahle, L.; Grote, D. P.; Halaxa, E.; Henestroza, E.; Kwan, J. W. & Mac Laren, S. A.
System: The UNT Digital Library
Recent progress in inertial confinement fusion at the Lawrence Livermore Laboratory (open access)

Recent progress in inertial confinement fusion at the Lawrence Livermore Laboratory

The Shiva and Argus laser systems at Livermore have been developed to study the physics of inertial confinement fusion. Both laser system designs are predicated on the use of large aperture Nd-glass disk amplifiers and high power spatial filters. During the past year we have irradiated DT filled microshell targets with and without polymer coatings. Recently new instruments have been developed to investigate implosion dynamics and to determine the maximum fuel density achieved by these imploded fusion pellets. A series of target irradiations with thin wall microshells at 15 to 20 TW, exploding pusher designs, resulted in a maximum neutron yield of 3 x 10/sup 10/. Polymer coated microshells designed for high compression were subjected to 4 kJ for 0.2 ns and reached fuel densities of 2.0 to 3.0 gm/cm/sup 3/. Results of these and other recent experiments will be reviewed.
Date: October 15, 1979
Creator: Ahlstrom, H. G. & Manes, K. R.
System: The UNT Digital Library
Overcoming Scalability Challenges for Tool Daemon Launching (open access)

Overcoming Scalability Challenges for Tool Daemon Launching

Many tools that target parallel and distributed environments must co-locate a set of daemons with the distributed processes of the target application. However, efficient and portable deployment of these daemons on large scale systems is an unsolved problem. We overcome this gap with LaunchMON, a scalable, robust, portable, secure, and general purpose infrastructure for launching tool daemons. Its API allows tool builders to identify all processes of a target job, launch daemons on the relevant nodes and control daemon interaction. Our results show that Launch-MON scales to very large daemon counts and substantially enhances performance over existing ad hoc mechanisms.
Date: February 15, 2008
Creator: Ahn, D H; Arnold, D C; de Supinski, B R; Lee, G L; Miller, B P & Schulz, M
System: The UNT Digital Library
Effect of non-axisymmetric magnetic perturbations on divertor profiles in NSTX H-mode plasmas (open access)

Effect of non-axisymmetric magnetic perturbations on divertor profiles in NSTX H-mode plasmas

None
Date: June 15, 2010
Creator: Ahn, J W; Canik, J; Maingi, R; Gray, T; McLean, A; Roquemore, A L et al.
System: The UNT Digital Library
Hydrogen speciation in hydrated layers on nuclear waste glass (open access)

Hydrogen speciation in hydrated layers on nuclear waste glass

The hydration of an outer layer on nuclear waste glasses is known to occur during leaching, but the actual speciation of hydrogen (as water or hydroxyl groups) in these layers has not been determined. As part of the Nevada Nuclear Waste Storage Investigations Project, we have used infrared spectroscopy to determine hydrogen speciations in three nuclear waste glass compositions (SRL-131 & 165, and PNL 76-68), which were leached at 90{sup 0}C (all glasses) or hydrated in a vapor-saturated atmosphere at 202{sup 0}C (SRL-131 only). Hydroxyl groups were found in the surface layers of all the glasses. Molecular water was found in the surface of SRL-131 and PNL 76-68 glasses that had been leached for several months in deionized water, and in the vapor-hydrated sample. The water/hydroxyl ratio increases with increasing reaction time; molecular water makes up most of the hydrogen in the thick reaction layers on vapor-phase hydrated glass while only hydroxyl occurs in the least reacted samples. Using the known molar absorptivities of water and hydroxyl in silica-rich glass the vapor-phase layer contained 4.8 moles/liter of molecular water, and 0.6 moles water in the form hydroxyl. A 15 {mu}m layer on SRL-131 glass formed by leaching at 90{sup 0}C …
Date: January 15, 1987
Creator: Aines, R. D.; Weed, H. C. & Bates, J. K.
System: The UNT Digital Library
Environmental Stewardship: How Semiconductor Suppliers Help to Meet Energy-Efficiency Regulations and Voluntary Specifications in China (open access)

Environmental Stewardship: How Semiconductor Suppliers Help to Meet Energy-Efficiency Regulations and Voluntary Specifications in China

Recognizing the role that semiconductor suppliers can playin meeting energy-efficiency regulations and voluntary specifications,this paper provides an overview of Chinese policies and implementingbodies; a discussion of current programs, their goals, and effectiveness;and possible steps that can be taken tomeet these energy-efficiencyrequirements while also meeting products' high performance and costgoals.
Date: January 15, 2007
Creator: Aizhen, Li; Fanara, Andrew; Fridley, David; Merriman, Louise & Ju, Jeff
System: The UNT Digital Library
Gamma-ray optical counterpart search experiment (GROCSE) (open access)

Gamma-ray optical counterpart search experiment (GROCSE)

The requirements of a gamma-ray burst optical counterpart detector are reviewed. By taking advantage of real-time notification of bursts, new instruments can make sensitive searches while the gamma-ray transient is still in progress. A wide field of view camera at Livermore National Laboratories has recently been adapted for detecting GRB optical counterparts to a limiting magnitude of 8. A more sensitive camera, capable of reaching m{sub upsilon} = 14, is under development.
Date: December 15, 1993
Creator: Akerlof, C.; Fatuzzo, M.; Lee, B.; Bionta, R.; Ledebuhr, A.; Park, H. S. et al.
System: The UNT Digital Library
Hot Electron Generation and Transport Using K(alpha) Emission (open access)

Hot Electron Generation and Transport Using K(alpha) Emission

We have conducted experiments on both the Vulcan and Titan laser facilities to study hot electron generation and transport in the context of fast ignition. Cu wires attached to Al cones were used to investigate the effect on coupling efficiency of plasma surround and the pre-formed plasma inside the cone. We found that with thin cones 15% of laser energy is coupled to the 40{micro}m diameter wire emulating a 40{micro}m fast ignition spot. Thick cone walls, simulating plasma in fast ignition, reduce coupling by x4. An increase of prepulse level inside the cone by a factor of 50 reduces coupling by a factor of 3.
Date: October 15, 2009
Creator: Akli, K. U.; Stephens, R. B.; Key, M. H.; Bartal, T.; Beg, F. N.; Chawla, S. et al.
System: The UNT Digital Library
Proton Decay Studies of the Light Lu, Tm and Ho Isotopes (open access)

Proton Decay Studies of the Light Lu, Tm and Ho Isotopes

A double-sided Si-strip detector system has been installed and commissioned at the focal plane of the Recoil Mass Spectrometer at the Holifield Radioactive Ion Beam Facility. The system can be used for heavy charged particle emission studies with half-lives as low as a few {micro}sec. In this paper the authors present identification and study of the decay properties of the five new proton emitters: {sup 140}Ho, {sup 141m}Ho, {sup 145}Tm, {sup 150m}Lu and {sup 151m}Lu.
Date: October 15, 1998
Creator: Akovali, Y.; Batchelder, J. C.; Bingham, C. R.; Davinson, T.; Ginter, T. N.; Gross, C. J. et al.
System: The UNT Digital Library
Evaluating Alternative Responses to Safeguards Alarms (open access)

Evaluating Alternative Responses to Safeguards Alarms

This paper describes a quantitative approach to help evaluate and respond to safeguards alarms. These alarms may be generated internally by a facility's safeguards systems or externally by individuals claiming to have stolen special nuclear material (SNM). This approach can be used to identify the most likely cause of an alarm - theft, hoax, or error - and to evaluate alternative responses to alarms. Possible responses include conducting investigations, initiating measures to recover stolen SNM, and replying to external threats. Based on the results of each alarm investigation step, the evaluation revises the likelihoods of possible causes of an alarm, and uses this information to determine the optimal sequence of further responses. The choice of an optimal sequence of responses takes into consideration the costs and benefits of successful thefts or hoaxes. These results provide an analytical basis for setting priorities and developing contingency plans for responding to safeguards alarms.
Date: April 15, 1982
Creator: Al-Ayat, R. A.; Judd, B. R. & McCord, R. K.
System: The UNT Digital Library
ASSESS (Analytic System and Software for Evaluating Safeguards and Security) update: Current status and future developments (open access)

ASSESS (Analytic System and Software for Evaluating Safeguards and Security) update: Current status and future developments

The Analytic System and Software for Evaluating Safeguards and Security (ASSESS) has been released for use by DOE field offices and their contractors. In October, 1989, we offered a prototype workshop to selected representatives of the DOE community. Based on the prototype results, we held the first training workshop at the Central Training Academy in January, 1990. Four additional workshops are scheduled for FY 1990. ASSESS is a state-of-the-art analytical tool for management to conduct integrated evaluation of safeguards systems at facilities handling facilities. Currently, ASSESS focuses on the threat of theft/diversion of special nuclear material by insiders, outsiders, and a special form of insider/outsider collusion. ASSESS also includes a neutralization module. Development of the tool is continuing. Plans are underway to expand the capabilities of ASSESS to evaluate against violent insiders, to validate the databases, to expand the neutralization module, and to assist in demonstrating compliance with DOE Material Control and Accountability (MC A) Order 5633.3. These new capabilities include the ability to: compute a weighted average for performance capability against a spectrum of insider adversaries; conduct defense-in-depth analyses; and analyze against protracted theft scenarios. As they become available, these capabilities will be incorporated in our training program. ASSESS …
Date: July 15, 1990
Creator: Al-Ayat, R.A. (Lawrence Livermore National Lab., CA (USA)); Cousins, T.D. (USDOE, Washington, DC (USA)) & Hoover, E.R. (Sandia National Labs., Albuquerque, NM (USA))
System: The UNT Digital Library
Neutrino telescopes as a direct probe of supersymmetrybreaking (open access)

Neutrino telescopes as a direct probe of supersymmetrybreaking

We consider supersymmetric models where the scale of supersymmetry breaking lies between 5 x 10{sup 6} GeV and 5 x 10{sup 8} GeV. In this class of theories, which includes models of gauge mediated supersymmetry breaking, the lightest supersymmetric particle is the gravitino. The next to lightest supersymmetric particle is typically a long lived charged slepton with a lifetime between a microsecond and a second, depending on its mass. Collisions of high energy neutrinos with nucleons in the earth can result in the production of a pair of these sleptons. Their very high boost means they typically decay outside the earth. We investigate the production of these particles by the diffuse flux of high energy neutrinos, and the potential for their observation in large ice or water Cerenkov detectors. The relatively small cross-section for the production of supersymmetric particles is partially compensated for by the very long range of heavy particles. The signal in the detector consists of two parallel charged tracks emerging from the earth about 100 meters apart, with very little background. A detailed calculation using the Waxman-Bahcall limit on the neutrino flux and realistic spectra shows that km{sup 3} experiments could see as many as 4 events …
Date: December 15, 2003
Creator: Albuquerque, Ivone; Burdman, Gustavo & Chacko, Z.
System: The UNT Digital Library
Helium measurements of pore-fluids obtained from SAFOD drillcore (open access)

Helium measurements of pore-fluids obtained from SAFOD drillcore

{sup 4}He accumulated in fluids is a well established geochemical tracer used to study crustal fluid dynamics. Direct fluid samples are not always collectable; therefore, a method to extract rare gases from matrix fluids of whole rocks by diffusion has been adapted. Helium was measured on matrix fluids extracted from sandstones and mudstones recovered during the San Andreas Fault Observatory at Depth (SAFOD) drilling in California, USA. Samples were typically collected as subcores or from drillcore fragments. Helium concentration and isotope ratios were measured 4-6 times on each sample, and indicate a bulk {sup 4}He diffusion coefficient of 3.5 {+-} 1.3 x 10{sup -8} cm{sup 2}s{sup -1} at 21 C, compared to previously published diffusion coefficients of 1.2 x 10{sup -18} cm{sup 2}s{sup -1} (21 C) to 3.0 x 10{sup -15} cm{sup 2}s{sup -1} (150 C) in the sands and clays. Correcting the diffusion coefficient of {sup 4}He{sub water} for matrix porosity ({approx}3%) and tortuosity ({approx}6-13) produces effective diffusion coefficients of 1 x 10{sup -8} cm{sup 2}s{sup -1} (21 C) and 1 x 10{sup -7} (120 C), effectively isolating pore fluid {sup 4}He from the {sup 4}He contained in the rock matrix. Model calculations indicate that <6% of helium initially …
Date: April 15, 2010
Creator: Ali, S.; Stute, M.; Torgersen, T.; Winckler, G. & Kennedy, B.M.
System: The UNT Digital Library
Tests and Calibration of the NIF Neutron Time of Flight Detectors (open access)

Tests and Calibration of the NIF Neutron Time of Flight Detectors

The National Ignition Facility (NIF) Neutron Time of Flight (NTOF) diagnostic will measure neutron yield and ion temperature in all NIF campaigns in DD, DT, and THD* implosions. The NIF NTOF diagnostic is designed to measure neutron yield from 109 to 2 x 1019. The NTOF consists of several detectors of varying sensitivity located on the NIF at about 5 m and 20 m from the target. Production, testing, and calibration of the NIF NTOF detectors have begun at the Laboratory for Laser Energetics (LLE). Operational tests of the NTOF detectors were performed on several facilities including the OMEGA laser at LLE and the Titan laser at Lawrence Livermore National Laboratory (LLNL). Neutron calibrations were carried out on the OMEGA laser. Results of the NTOF detectors tests and calibration will be presented. *(D = deuterium, T = tritium, H = hydrogen)
Date: May 15, 2008
Creator: Ali, Z. A.; Glebov, V. Yu.; Cruz, M.; Duffy, T.; Stoeckl, C.; Roberts, S. et al.
System: The UNT Digital Library
ALPS - advanced limiter-divertor plasma-facing systems. (open access)

ALPS - advanced limiter-divertor plasma-facing systems.

The Advanced Limiter-divertor Plasma-facing Systems (ALPS) program was initiated in order to evaluate the potential for improved performance and lifetime for plasma-facing systems. The main goal of the program is to demonstrate the advantages of advanced limiter/divertor systems over conventional systems in terms of power density capability, component lifetime, and power conversion efficiency, while providing for safe operation and minimizing impurity concerns for the plasma. Most of the work to date has been applied to free surface liquids. A multi-disciplinary team from several institutions has been organized to address the key issues associated with these systems. The main performance goals for advanced limiters and diverters are a peak heat flux of >50 MW/m{sup 2},elimination of a lifetime limit for erosion, and the ability to extract useful heat at high power conversion efficiency ({approximately}40%). The evaluation of various options is being conducted through a combination of laboratory experiments, modeling of key processes, and conceptual design studies. The current emphasis for the work is on the effects of free surface liquids on plasma edge performance.
Date: September 15, 1999
Creator: Allain, J. P.; Bastasz, R.; Brooks, J. N.; Evans, T.; Hassanein, A.; Luckhardt, S. et al.
System: The UNT Digital Library
The Snowmass points and slopes : benchmarks for SUSY searches. (open access)

The Snowmass points and slopes : benchmarks for SUSY searches.

The ''Snowmass Points and Slopes'' (SPS) are a set of benchmark points and parameter lines in the MSSM parameter space corresponding to different scenarios in the search for Supersymmetry at present and future experiments. This set of benchmarks was agreed upon at the 2001 ''Snowmass Workshop on the Future of Particle Physics'' as a consensus based on different existing proposals.
Date: April 15, 2002
Creator: Allanach, B. C.; Battaglia, M.; Blair, G. A.; Carena, M.; De Roeck, A. & Wagner, C. E. M.
System: The UNT Digital Library
Design and Performance Characteristics of the ORNL AdvancedMicroscopy Laboratory and JEOL 2200FS-AC Aberration-CorrectedSTEM/TEM (open access)

Design and Performance Characteristics of the ORNL AdvancedMicroscopy Laboratory and JEOL 2200FS-AC Aberration-CorrectedSTEM/TEM

At ORNL, the new Advanced Microscopy Laboratory (AML) has recently been completed, with two aberration-corrected instruments installed, and two more planned in the near future to fill the 4-laboratory building. The installed JEOL 2200FS-AC has demonstrated aTEM information limit of 0.9A. This limit is expected given the measured instrument parameters (HT and OL power supply stabilities, beam energy spread, etc.), and illustrates that the environmental influences are not adversely affecting the instrument performance. In STEM high-angle annular dark-field (HA-ADF) mode, images of a thin Si crystal in<110>zone axis orientation, after primary aberrations in the illuminating beam were optimally corrected, showed a significant vibration effect. The microscope is fitted with three magnetically levitated turbo pumps (one on the column at about the specimen position,and two near floor level) that pump the Omega energy filter and detector chamber. These pumps run at 48,000 rpm, precisely equivalent to 800Hz. It was determined that the upper turbo pump was contributing essentially all of the 800Hz signal to the image, and in fact that the pump was defective. After replacing the pump with one significantly quieter than the original, the Si atomic column image and associated diffractogram(Fig. 4b) show a much-reduced effect of the 800Hz …
Date: February 15, 2005
Creator: Allard, Lawrence F.; Blom, Douglas A.; O'Keefe, Michael A. & Mishina, S.
System: The UNT Digital Library
Experimental Quenching of Harmonic Stimuli: Universality of Linear Response Theory (open access)

Experimental Quenching of Harmonic Stimuli: Universality of Linear Response Theory

This article discusses experimental quenching of harmonic stimuli.
Date: July 15, 2009
Creator: Allegrini, Paolo; Bologna, Mauro; Fronzoni, Leone; Grigolini, Paolo & Silvestri, Ludovico
System: The UNT Digital Library