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IUPAC Statues and Bylaws. (open access)

IUPAC Statues and Bylaws.

From the history of the Commission, it began with a large number of members. It was found that it was difficult to gain agreement by correspondence between such a large group. A smaller group was elected to operate by correspondence and make decisions. It operated successfully for a half century in this manner. With funding available, the Commission membership grew larger but they.discussed all matters face to face at Commission meetings. Subcommittees were appointed to pursue specialized topics and members reported and discussed their subcommittee results directly to the Commission at the face to face meetings. With the change in the bylaws, future face to face meetings will no longer be an option for the members of the Commission and its subcommittees, unless all members provide their own funds or those of their host institutions. The funding and membership restrictions are all serious topics, which require a thorough discussion.
Date: August 8, 2003
Creator: Holden, Norman E.
System: The UNT Digital Library
Rep-Rated X-ray Damage and Ablation Experiments for IFE and ICF Applications (open access)

Rep-Rated X-ray Damage and Ablation Experiments for IFE and ICF Applications

The response of materials to high-dose x-ray exposures needs to be understood for inertial fusion energy (IFE) and inertial confinement fusion applications, where the requirements for IFE are considerably more stringent. In the IFE context, x-ray damage and/or small levels of ablation are of importance for component survivability, generation of debris, and contamination. Ablation quantities of even 1 angstrom per shot would result in material removal of more than 1 cm per year of operation. If even one part in a million of this material made its way to the final optics, it would coat them with a thickness equivalent to several waves of the laser light. Also, small-scale melting and thermomechanical effects, such as fatigue, can result from x-ray heating. These effects potentially become important when multiple shots are considered, and thus, their study requires use of rep-rated experiments. As a part of the High-Average Power Laser Program, the XAPPER experiment has been initiated at Lawrence Livermore National Laboratory. XAPPER produces high doses of low-energy x-rays at repetition rates of up to 10 Hz. Study of x-ray damage is underway. An overview of facility capabilities, results to date, and future plans are provided.
Date: September 8, 2003
Creator: Latkowski, J. F.; Abbott, R. P.; Payne, S. A.; Reyes, S.; Schmitt, R. C. & Speth, J. A.
System: The UNT Digital Library
Enhancing Scalability of Parallel Structured AMR Calculations (open access)

Enhancing Scalability of Parallel Structured AMR Calculations

None
Date: May 8, 2003
Creator: Wissink, A M; Hysom, D & Hornung, R
System: The UNT Digital Library
CHIRPED PULSE AMPLIFICATION OF HGHG-FEL FACILITY AT BNL. (open access)

CHIRPED PULSE AMPLIFICATION OF HGHG-FEL FACILITY AT BNL.

The DUV-FEL facility has been in operation in High Gain Harmonic Generation (HGHG) mode for one year producing 266 nm output from 177 MeV electrons. In this paper we present preliminary results of the Chirped Pulse Amplification (CPA) of HGHG radiation. In the normal HGHG process, a 1 ps electron beam is seeded by chirped 9 ps long 800 nm Ti:Sapphire laser. The electron beam sees only a narrow fraction of the seed laser bandwidth. However, in the CPA case the seed laser pulse length is reduced to 1 ps, and the electron beam sees the full bandwidth. We introduce an energy chirp on electron beam to match the chirp of the seed pulse, enabling the resonant condition for the whole beam. We present measurements of the spectrum bandwidth for various chirp conditions.
Date: September 8, 2003
Creator: DOYURAN,A. ET AL.
System: The UNT Digital Library
Is U3Ni3Sn4 best described as near a quantum critical point? (open access)

Is U3Ni3Sn4 best described as near a quantum critical point?

Although most known non-Fermi liquid (NFL) materials are structurally or chemically disordered, the role of this disorder remains unclear. In particular, very few systems have been discovered that may be stoichiometric and well ordered. To test whether U{sub 3}Ni{sub 3}Sn{sub 4} belongs in this latter class, we present measurements of the x-ray absorption fine structure (XAFS) of polycrystalline and single-crystal U{sub 3}Ni{sub 3}Sn{sub 4} samples that are consistent with no measurable local atomic disorder. We also present temperature-dependent specific heat data in applied magnetic fields as high as 8 T that show features that are inconsistent with the antiferromagnetic Griffiths' phase model, but do support the conclusion that a Fermi liquid/NFL crossover temperature increases with applied field. These results are inconsistent with theoretical explanations that require strong disorder effects, but do support the view that U{sub 3}Ni{sub 3}Sn{sub 4} is a stoichoiometric, ordered material that exhibits NFL behavior, and is best described as being near an antiferromagnetic quantum critical point.
Date: April 8, 2003
Creator: Booth, C. H.; Shlyk, L.; Nenkov, K.; Huber, J. G. & De Long, L. E.
System: The UNT Digital Library
Seismic imaging of reservoir flow properties: Time-lapse pressurechanges (open access)

Seismic imaging of reservoir flow properties: Time-lapse pressurechanges

Time-lapse fluid pressure and saturation estimates are sensitive to reservoir flow properties such as permeability. In fact, given time-lapse estimates of pressure and saturation changes, one may define a linear partial differential equation for permeability variations within the reservoir. The resulting linear inverse problem can be solved quite efficiently using sparse matrix techniques. An application to a set of crosswell saturation and pressure estimates from a CO{sub 2} flood at the Lost Hills field in California demonstrates the utility of this approach. From the crosswell estimates detailed estimates of reservoir permeability are produced. The resulting permeability estimates agree with a permeability log in an adjacent well and are in accordance with water and CO{sub 2} saturation changes in the interwell region.
Date: April 8, 2003
Creator: Vasco, Don W.
System: The UNT Digital Library
RF Power Detector/Monitor Upgrade for the 500MHz Systems at the ALS (open access)

RF Power Detector/Monitor Upgrade for the 500MHz Systems at the ALS

Several systems rely on the accurate and linear detection of 500 MHz signals, (the fundamental frequency of both the Booster Ring and Storage Ring) over a dynamic range in excess of 25dB. Prior to this upgrade, the detector/monitor was diode based and though this type of detector could handle the dynamic range requirement it could not do so in an accurate and linear manner. In order to meet the requirements (dynamic range greater than or equal to 25dB, accurate and linear to +-0.25dB over the range, and additional circuitry to interface to the legacy control system and interlocks), a new RF Power Detector/Monitor has been developed using two AD8361, Analog Devices Tru RMS Detectors and a fuzzy comparator, which extends the overall detector's range to twice that of the AD8361. Further information is available [www.analogedevices.com/]. Details of the design requirements and the detector/monitor's circuit as well as the performance of the detector will be presented.
Date: May 8, 2003
Creator: Baptiste, K.
System: The UNT Digital Library
In-situ reduction of Cr(VI) in heavily contaminated soils through organic carbon amendment (open access)

In-situ reduction of Cr(VI) in heavily contaminated soils through organic carbon amendment

None
Date: May 8, 2003
Creator: Tokunaga, Tetsu K.; Wan, Jiamin; Firestone, Mary K.; Hazen, Terry C.; Olson, Keith R.; Herman, Donald J. et al.
System: The UNT Digital Library
D0-D bar 0 mixing and rare charm decays (open access)

D0-D bar 0 mixing and rare charm decays

We review the current status of flavor-changing neutral currents in the charm sector. We focus on the standard-model predictions and identify the main sources of theoretical uncertainties in both D{sup 0} - {bar D}{sup 0} mixing and rare charm decays. The potential of these observables for constraining short-distance physics in the standard model and its extensions is compromised by the presence of large nonperturbative effects. We examine the possible discovery windows in which short-distance physics can be tested and study the effects of various extensions of the standard model. The current experimental situation and future prospects are reviewed.
Date: October 8, 2003
Creator: Burdman, Gustavo & Shipsey, Ian
System: The UNT Digital Library
The response of a spherical tissue-equivalent proportional counter to different ions having similar LET. (open access)

The response of a spherical tissue-equivalent proportional counter to different ions having similar LET.

None
Date: September 8, 2003
Creator: Guetersloh, S.; Borak, T.; Taddei, P.; Zeitlin, C.; Heilbronn, L.; Miller, J. et al.
System: The UNT Digital Library
Hom dampers for ALS storage ring RF cavities (open access)

Hom dampers for ALS storage ring RF cavities

The main source of narrowband impedance in the Advanced Light Source (ALS) are higher order modes (HOMs) of the two main RF and three third harmonic cavities. These HOMs drive longitudinal and transverse coupled bunch instabilities, which are controlled using active beam feedback systems. The dominant longitudinal HOMs in both systems are TM011-like modes with the R/Q factor an order of magnitude higher than all other longitudinal modes. To reduce the growth rates within the range of the longitudinal feedback system (LFB), these modes were tuned away from beam resonances by means of cooling water temperature control (main rf system), and the combination of two tuners (third harmonic system). To improve the reliability of the longitudinal dampening system, we have built and installed E-type HOM dampers for the fundamental and harmonic cavities. We present the design, commissioning and performance of the HOM dampers in this paper.
Date: May 8, 2003
Creator: Kwiatkowski, S.; Baptiste, K.; Byrd, J.; DeSantis, S.; Julian, J.; Low, R. et al.
System: The UNT Digital Library
Pressure diffusion waves in porous media (open access)

Pressure diffusion waves in porous media

Pressure diffusion wave in porous rocks are under consideration. The pressure diffusion mechanism can provide an explanation of the high attenuation of low-frequency signals in fluid-saturated rocks. Both single and dual porosity models are considered. In either case, the attenuation coefficient is a function of the frequency.
Date: April 8, 2003
Creator: Silin, Dmitry; Korneev, Valeri & Goloshubin, Gennady
System: The UNT Digital Library
Carbon sequestration in natural gas reservoirs: Enhanced gas recovery and natural gas storage (open access)

Carbon sequestration in natural gas reservoirs: Enhanced gas recovery and natural gas storage

Natural gas reservoirs are obvious targets for carbon sequestration by direct carbon dioxide (CO{sub 2}) injection by virtue of their proven record of gas production and integrity against gas escape. Carbon sequestration in depleted natural gas reservoirs can be coupled with enhanced gas production by injecting CO{sub 2} into the reservoir as it is being produced, a process called Carbon Sequestration with Enhanced Gas Recovery (CSEGR). In this process, supercritical CO{sub 2} is injected deep in the reservoir while methane (CH{sub 4}) is produced at wells some distance away. The active injection of CO{sub 2} causes repressurization and CH{sub 4} displacement to allow the control and enhancement of gas recovery relative to water-drive or depletion-drive reservoir operations. Carbon dioxide undergoes a large change in density as CO{sub 2} gas passes through the critical pressure at temperatures near the critical temperature. This feature makes CO{sub 2} a potentially effective cushion gas for gas storage reservoirs. Thus at the end of the CSEGR process when the reservoir is filled with CO{sub 2}, additional benefit of the reservoir may be obtained through its operation as a natural gas storage reservoir. In this paper, we present discussion and simulation results from TOUGH2/EOS7C of gas …
Date: April 8, 2003
Creator: Oldenburg, Curtis M.
System: The UNT Digital Library
Nanoscale topography control for the fabrication of advanced diffractive optics (open access)

Nanoscale topography control for the fabrication of advanced diffractive optics

None
Date: September 8, 2003
Creator: Liddle, Alexander J.; Farhad, Salmassi; Naulleau, Patrick P. & Gullikson, Eric M.
System: The UNT Digital Library
Azimuthally sensitive HBT in Au+Au collisions at sqrt(snn) = 200 GeV (open access)

Azimuthally sensitive HBT in Au+Au collisions at sqrt(snn) = 200 GeV

No abstract prepared.
Date: December 8, 2003
Creator: Adams, J.; Adler, C.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D. et al.
System: The UNT Digital Library
Fully depleted back-illuminated p-channel CCD development (open access)

Fully depleted back-illuminated p-channel CCD development

An overview of CCD development efforts at Lawrence Berkeley National Laboratory is presented. Operation of fully-depleted, back-illuminated CCD's fabricated on high resistivity silicon is described, along with results on the use of such CCD's at ground-based observatories. Radiation damage and point-spread function measurements are described, as well as discussion of CCD fabrication technologies.
Date: July 8, 2003
Creator: Bebek, Chris J.; Bercovitz, John H.; Groom, Donald E.; Holland, Stephen E.; Kadel, Richard W.; Karcher, Armin et al.
System: The UNT Digital Library
Remote operations in a global accelerator network (open access)

Remote operations in a global accelerator network

The INTRODUCTION to this paper summarizes the history of the Global Accelerator Network (GAN) concept and the recent workshops that discussed the relationship between GAN and Remote Operations. The REMOTE OPERATIONS SCENARIOS section brings out the organizational philosophy embodied in GAN-like and to non-GAN-like scenarios. The set of major TOPICS RAISED AT THE WORKSHOPS are only partially resolved. COLLABORATION TOOLS are described and discussed, followed by examples of REMOTE ACCELERATOR CONTROL PROJECTS around the world.
Date: May 8, 2003
Creator: Peggs, Steve; Satogata, Todd; Agarwal, Deborah & Rice, David
System: The UNT Digital Library
Selection of Batteries and Fuel Cells for Yucca Mountain Robots (open access)

Selection of Batteries and Fuel Cells for Yucca Mountain Robots

The Performance Confirmation program of the Yucca Mountain Repository Development Project needs to employ remotely operated robots to work inside the emplacement drifts which will have an environment unsuitable for humans (radiation environment of up to 200 rad/hour (mostly gamma rays, some neutrons)) and maximum temperatures of 180 C. The robots will be required to operate inside the drifts for up to 8 hours per mission. Based on available functional requirements, we have developed the following specifications for the power needed by the robots:
Date: December 8, 2003
Creator: Upadhye, R S
System: The UNT Digital Library
Hot Electron Measurement and Modeling for Short-Pulse Laser Plasma Interactions (open access)

Hot Electron Measurement and Modeling for Short-Pulse Laser Plasma Interactions

We measured the hot electron production from short pulse laser plasma interactions using a fiber-array-based compact electron spectrometer that uses permanent magnets for electron energy dispersion and over 100 scintillating fibers coupled to a 1024 x 1024 pixel CCD as the detection system. This spectrometer has electron energy coverage from 10 keV to 60 MeV. The whole spectrometer is compact with dimensions of 8 inch x 7 inch x 4 inch. We performed systematic measurements of electron production on the ultra short pulse laser JanUSP (with pulse width less than 100 fs) at intensity range interest to Fast Ignition scheme from 10{sup 17} Wcm{sup -2} up to 10{sup 19} Wcm{sup -2} at Lawrence Livermore National laboratory. The electron distributions were obtained at various laser energies for different solid target materials and observation angles. We determined characteristic temperature of the escaped hot electrons at various incident laser intensity which is confirmed by theoretical simulations using the ZOHAL Particle-in-cell (PIC) code.
Date: September 8, 2003
Creator: Chen, H; McLean, S; Patel, P K & Wilks, S C
System: The UNT Digital Library
Monitoring Permeable Reactive Barriers using Electrical Resistance Tomography (open access)

Monitoring Permeable Reactive Barriers using Electrical Resistance Tomography

An electrical resistivity tomography (ERT) method is being evaluated as a measurement tool to determine the integrity of permeable reactive barriers (PRBs) during and after construction of the barrier and as a monitoring tool to determine the long-term operational health of the barrier. The method is novel because it inserts the electrodes directly into the barrier itself. Numerical modeling calculations indicate that the ERT method can detect flaws (voids) in the barrier as small as 0.11 m{sup 2} (0.33 m x 0.33 m) when the aspect ratio of the electrodes are 2:1. Laboratory measurements indicate that the change in resistance over time of the iron-filling mixture used to create the PRB is sufficient for ERT to monitor the long-term health of the barrier. The use of this ERT method allows for the cost-effective installation of the barrier, especially when the vadose zone is large, because borehole installation methods, rather than trenching methods, can be used.
Date: December 8, 2003
Creator: Ramirez, A.; Bratton, W.; Maresca, J.; Daily, W. & Dickerson, W.
System: The UNT Digital Library
The Solid-State Heat-Capacity Laser (open access)

The Solid-State Heat-Capacity Laser

Heat-capacity operation of a laser is a novel method by which high average powers can be generated. In this paper, we present the principles behind heat-capacity operation, in addition to describing the results of recent experiments.
Date: December 8, 2003
Creator: Rotter, M D; Dane, C B; Gonzales, S A; Merrill, R D; Mitchell, S C; Parks, C W et al.
System: The UNT Digital Library
THE RESUMMED HIGGS BOSON TRANSVERSE MOMENTUM DISTRIBUTION AT THE LHC. (open access)

THE RESUMMED HIGGS BOSON TRANSVERSE MOMENTUM DISTRIBUTION AT THE LHC.

We apply QCD resummation techniques to study the transverse momentum distribution of Higgs bosons produced via gluon-gluon fusion at the LHC. In particular we focus on the joint resummation formalism which resume both threshold and transverse momentum corrections simultaneously. A comparison of results obtained in the joint and the standard recoil resummation frameworks is presented.
Date: December 8, 2003
Creator: KULESZA,A. STERMAN,G. VOGELSANG,W.
System: The UNT Digital Library
Transition to Detonation in Exploding Bridgewire Detonators (open access)

Transition to Detonation in Exploding Bridgewire Detonators

We are investigating using breakout profile measurements and/or Fabry-Perot velocimeter measurements during early stages of initiation in Exploding Bridge Wire (EBW) detonators as a tool for understanding the physics of initiation of these devices and as a tool for monitoring aging effects. We believe any changes due to aging may be more readily observed in the very early stages of the initiation. We have developed a method that allows measurement of the detonation velocity, detonation profile and interface velocity as a function of distance from the bridgewire.
Date: January 8, 2003
Creator: Roeski, F.; Benterou, J.; Lee, R. & Roos, R.
System: The UNT Digital Library