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Improved Energy Coupling into the Gain Region of the Ni-Like Pd Transient Collisional X-Ray Laser (open access)

Improved Energy Coupling into the Gain Region of the Ni-Like Pd Transient Collisional X-Ray Laser

We present within this paper a series of experiments, which yield new observations to further our understanding of the transient collisional x-ray laser medium. We use the recently developed technique of picosecond x-ray laser interferometry to probe the plasma conditions in which the x-ray laser is generated and propagates. This yields two dimensional electron density maps of the plasma taken at different times relative to the peak of the 600ps plasma-forming beam. In another experimental campaign, the output of the x-ray laser plasma column is imaged with a spherical multilayer mirror onto a CCD camera to give a two-dimensional intensity map of the x-ray laser output. Near-field imaging gives insights into refraction, output intensity and spatial mode structure. Combining these images with the density maps gives an indication of the electron density at which the x-ray laser is being emitted at (yielding insights into the effect of density gradients on beam propagation). Experimental observations coupled with simulations predict that most effective coupling of laser pump energy occurs when the duration of the main heating pulse is comparable to the gain lifetime ({approx}10ps for Ni-like schemes). This can increase the output intensity by more than an order of magnitude relative to …
Date: October 5, 2004
Creator: Smith, R.; Dunn, J.; Filevich, J.; Moon, S.; Nilsen, J.; Keenan, R. et al.
Object Type: Article
System: The UNT Digital Library
Dangerous Waste Characteristics of Contact-Handled Transuranic Mixed Wastes from Hanford Tanks (open access)

Dangerous Waste Characteristics of Contact-Handled Transuranic Mixed Wastes from Hanford Tanks

This report summarizes existing analytical data gleaned from samples taken from the Hanford tanks designated as potentially containing transuranic mixed process wastes. Process knowledge of the wastes transferred to these tanks has been reviewed to determine whether the dangerous waste characteristics now assigned to all Hanford underground storage tanks are applicable to these particular wastes. Supplemental technologies are being examined to accelerate the Hanford tank waste cleanup mission and accomplish waste treatment safely and efficiently. To date, 11 Hanford waste tanks have been designated as potentially containing contact-handled (CH) transuranic mixed (TRUM) wastes. The CH-TRUM wastes are found in single-shell tanks B-201 through B-204, T-201 through T-204, T-104, T-110, and T-111. Methods and equipment to solidify and package the CH-TRUM wastes are part of the supplemental technologies being evaluated. The resulting packages and wastes must be acceptable for disposal at the Waste Isolation Pilot Plant (WIPP). The dangerous waste characteristics being considered include ignitability, corrosivity, reactivity, and toxicity arising from the presence of 2,4,5-trichlorophenol at levels above the dangerous waste threshold. The analytical data reviewed include concentrations of sulfur, sulfate, cyanide, 2,4,5-trichlorophenol, total organic carbon, and oxalate; the composition of the tank headspace, pH, and mercury. Differential scanning calorimetry results …
Date: October 5, 2004
Creator: Tingey, Joel M.; Bryan, Garry H. & Deschane, Jaquetta R.
Object Type: Report
System: The UNT Digital Library
Possible Laminographic and Tomosynthesis Applications for Wolter Microscope Scan Geometries (open access)

Possible Laminographic and Tomosynthesis Applications for Wolter Microscope Scan Geometries

The Wolter microscope includes a number of attractive features for x-ray imaging, and possible connections to laminographic and tomosynthesis 3D object recovery algorithms. This type of instrument employs x-ray optics to sift out single energy x-rays from a broader spectral energy source, and direct those x-rays to a ''focus plane'' similar to the operation of a optical microscope (see Figure 1 for schematic of a Wolter instrument). Unlike optical microscopes the 3D object can be thick in the direction of the x-rays and in this case more of the intensity of the image is affected by the out-of-focus planes, since the ray-paths span the entire depth of the object. It is clear that the ''in-focus'' plane of a Wolter contain more 3D information than a simple ''point-projection'' radiograph. However, it is not clear just how the impact of the out-of-focus planes obscures or distorts features of interest for the in-focus planes. Further, it is not clear just how object positioning can be combined with multiple acquisitions to enable recovery of other planes within the object function or the entire object function. Of particular interest here are Wolter microscopes configured for mesoscale objects (mm extent with um features). Laminographic and tomosynthesis …
Date: October 5, 2004
Creator: Schneberk, D; Jackson, J & Martz, H
Object Type: Report
System: The UNT Digital Library
Management Prestart Review Phase 1 for the NIF Optics Assembly Building (OAB) (open access)

Management Prestart Review Phase 1 for the NIF Optics Assembly Building (OAB)

A Management Prestart Review (MPR) for the National Ignition Facility (NIF) Optics Assembly Building (OAB) was conducted from June, 2000, through October, 2000. This review was performed to determine readiness of the facility and management to transfer the facility from the construction to the commissioning and operations phase. This review process provides assurance that the appropriate line management is in place to effect the turnover. Completion and acceptance of this report constitutes a turnover of facility and equipment operational responsibility from the Beampath Infrastructure System Construction organization to the Assembly Installation and Refurbishment Operations (assembly equipment installation/activation and mechanical cleaning operations) and the Beampath Infrastructure System (BIS) Commissioning and Operations Organizations (conventional facility operations). The OAB MPR provides to the NIF Project Manager an independent, systematic assessment of: (1) Readiness of line management for the turnover to take place, (2) Completeness of the equipment and facility installation of the OAB, (3) Readiness of personnel to operate within the facility, and (4) Implementation and efficacy of key management control processes and procedures. The MPR process assures that the technical, cost, and schedule risk associated with the installation/activation of OAB special equipment, mechanical cleaning, and conventional facility operations within the OAB are …
Date: October 5, 2000
Creator: Dragoo, V.
Object Type: Report
System: The UNT Digital Library
Pressure Gradient Effects On Two-Dimensional Plasma Expansion (open access)

Pressure Gradient Effects On Two-Dimensional Plasma Expansion

Recent advances in interferometry has allowed for the characterization of the electron density expansion within a laser produced plasma to within 10 {micro}m of the target surface and over picosecond timescales. This technique employs the high brightness output of the transient gain Ni-like Pd collisional x-ray laser at 14.7 nm to construct an effective moving picture of the two-dimensional (2-D) expansion of the plasma. We present experimentally measured density profiles of an expanding Al plasma generated through laser irradiation in a 14mm line focus geometry. Significant lateral expansion was observed at all times as well as a pronounced on-axis electron density dip. Detailed modeling with a 2-D plasma physics code gives good agreement to experimental observations. Large pressure gradients associated with the tight focal spot conditions are calculated to dominate in shaping the plasma density profile.
Date: October 5, 2004
Creator: Moon, S.; Smith, R. F.; Dunn, J.; Keenan, R.; Nilsen, J.; Hunter, J. R. et al.
Object Type: Article
System: The UNT Digital Library
National Ignition Facility Target Chamber (open access)

National Ignition Facility Target Chamber

On June 11, 1999 the Department of Energy dedicated the single largest piece of the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) in Livermore, California. The ten (10) meter diameter aluminum target high vacuum chamber will serve as the working end of the largest laser in the world. The output of 192 laser beams will converge at the precise center of the chamber. The laser beams will enter the chamber in two by two arrays to illuminate 10 millimeter long gold cylinders called hohlraums enclosing 2 millimeter capsule containing deuterium, tritium and isotopes of hydrogen. The two isotopes will fuse, thereby creating temperatures and pressures resembling those found only inside stars and in detonated nuclear weapons, but on a minute scale. The NIF Project will serve as an essential facility to insure safety and reliability of our nation's nuclear arsenal as well as demonstrating inertial fusion's contribution to creating electrical power. The paper will discuss the requirements that had to be addressed during the design, fabrication and testing of the target chamber. A team from Sandia National Laboratories (SNL) and LLNL with input from industry performed the configuration and basic design of the target chamber. The method …
Date: October 5, 2000
Creator: Wavrik, R W; Cox, J R & Fleming, P J
Object Type: Article
System: The UNT Digital Library
Deformation At Crystallite Interfaces (open access)

Deformation At Crystallite Interfaces

Deformation at grain boundaries is observed and a framework for boundary specific constitutive laws based upon geometric considerations of slip transfer is developed. Orientation images of a pseudo-internal surface during interrupted channel die deformations of a Cu bi-crystal show the heterogeneity of lattice rotation near the grain boundary. The experiments demonstrate that a region near the boundary is strongly influenced by neighboring grain deformation and lend support to the development of deformation models that include the effects of non-local slip system interaction.
Date: October 5, 2001
Creator: Field, D P; Mortensen, A W; Nowell, M M & Campbell, G H
Object Type: Article
System: The UNT Digital Library
Dimensional Measurements of Three Tubes by Computed Tomography (open access)

Dimensional Measurements of Three Tubes by Computed Tomography

Low density polyethylene (LDPE), copper (Cu), and gold (Au) tubes were scanned on KCAT to identify and evaluate the impact of phase effects on quantitative object recovery. These tubes are phantoms for high energy density capsules.[Logan, et al. 2004] Digital radiographs for each tube are shown in Figure 1. The LDPE tube was scanned at 60 kV, while the Cu and the Au tubes were scanned at 140 kV. All tubes were scanned at a magnification of 3, with approximately 100-mm distance between the exit plane of the tube and the scintillator. Notice the prominence of the outer bright and inner dark edges for the LDPE tube DR, and their absence from the Cu and Au tube DRs. The bright and dark edges are a result of change in phase of the x-rays. The x-ray fluence is partly attenuated and partly refracted. The location near the outer edge of the tube appears to be more attenuating since those x-rays have refracted to locations just outside the tube. Alternatively, the added counts from the refraction result in intensities that are greater than the incident intensity effectively representing a ''negative attenuation''. This results in more counts in that location than in the …
Date: October 5, 2004
Creator: Schneberk, D. J.; Martz, H. E., Jr. & Brown, W. D.
Object Type: Report
System: The UNT Digital Library
Nuisance Source Population Modeling for Radiation Detection System Analysis (open access)

Nuisance Source Population Modeling for Radiation Detection System Analysis

A major challenge facing the prospective deployment of radiation detection systems for homeland security applications is the discrimination of radiological or nuclear 'threat sources' from radioactive, but benign, 'nuisance sources'. Common examples of such nuisance sources include naturally occurring radioactive material (NORM), medical patients who have received radioactive drugs for either diagnostics or treatment, and industrial sources. A sensitive detector that cannot distinguish between 'threat' and 'benign' classes will generate false positives which, if sufficiently frequent, will preclude it from being operationally deployed. In this report, we describe a first-principles physics-based modeling approach that is used to approximate the physical properties and corresponding gamma ray spectral signatures of real nuisance sources. Specific models are proposed for the three nuisance source classes - NORM, medical and industrial. The models can be validated against measured data - that is, energy spectra generated with the model can be compared to actual nuisance source data. We show by example how this is done for NORM and medical sources, using data sets obtained from spectroscopic detector deployments for cargo container screening and urban area traffic screening, respectively. In addition to capturing the range of radioactive signatures of individual nuisance sources, a nuisance source population model …
Date: October 5, 2009
Creator: Sokkappa, P; Lange, D; Nelson, K & Wheeler, R
Object Type: Report
System: The UNT Digital Library
KEY FACTORS THAT INFLUENCE THE PERFORMANCE PROPERTIES OF ARP/MCU SALTSTONE MIXES (open access)

KEY FACTORS THAT INFLUENCE THE PERFORMANCE PROPERTIES OF ARP/MCU SALTSTONE MIXES

At the Saltstone Production Facility (SPF), decontaminated salt solution (DSS) is combined with premix (a cementitious mixture of portland cement (PC), blast furnace slag (BFS) and Class F fly ash (FA)) in a Readco mixer to produce fresh (uncured) Saltstone. After transfer to the Saltstone Disposal Facility (SDF) the hydration reactions initiated during the contact of the premix and salt solution continue during the curing period to produce the hardened waste form product. The amount of heat generated from hydration and the resultant temperature increase in the vaults depend on the composition of the decontaminated salt solution being dispositioned as well as the grout formulation (mix design). This report details the results from Task 3 of the Saltstone Variability Study for FY09 which was performed to identify, and quantify when possible, those factors that drive the performance properties of the projected ARP/MCU Batches. A baseline ARP/MCU mix (at 0.60 water to cementitious materials (w/cm) ratio) was established and consisted of the normal premix composition and a salt solution that was an average of the projected compositions of the last three ARP/MCU batches developed by T. A. Le. This task introduced significant variation in (1) wt % slag, w/cm ratio, and …
Date: October 5, 2009
Creator: Harbour, J.; Edwards, T. & Williams, V.
Object Type: Report
System: The UNT Digital Library
Transition Plan for the K-1203 Sewage Treatment Plant, East Tennessee Technology Park, Oak Ridge, Tennessee (open access)

Transition Plan for the K-1203 Sewage Treatment Plant, East Tennessee Technology Park, Oak Ridge, Tennessee

The K-1203 Sewage Treatment Plant (STP) was previously used to treat and process all sanitary sewage waste from the East Tennessee Technology Park (ETTP). The plant was shut down on May 29, 2008 as a result of the transition of sewage treatment for ETTP to the City of Oak Ridge. The City of Oak Ridge expanded the Rarity Ridge Sewage Treatment Plant (RRSTP) to include capacity to treat the waste from the ETTP and the Community Reuse Organization of East Tennessee (CROET) constructed a new ETTP lift station and force main to RRSTP. In preparation for the shutdown of K-1203, the US Department of Energy (DOE) in conjunction with Operation Management International (OMI) developed a shut down plan to outline actions that need to occur prior to the transition of the facility to Bechtel Jacob Company, LLC (BJC) for decontamination and demolition (D and D). This plan outlines the actions, roles, and responsibilities for BJC in order to support the transition of the K-1203 STP from OMI to the BJC Surveillance and Maintenance (S and M) and D and D programs. The D and D of the K-1203 Facilities is planned under the Comprehensive Environmental Response, Compensation, and Liability Act …
Date: October 5, 2008
Creator: J., Hoffmeister
Object Type: Report
System: The UNT Digital Library
Tracking the Sun II: The Installed Cost of Photovoltaics in the U.S. from 1998-2008 (open access)

Tracking the Sun II: The Installed Cost of Photovoltaics in the U.S. from 1998-2008

Installations of solar photovoltaic (PV) systems have been growing at a rapid pace in recent years. In 2008, 5,948 MW of PV was installed globally, up from 2,826 MW in 2007, and was dominated by grid-connected applications. The United States was the world's third largest PV market in terms of annual capacity additions in 2008, behind Spain and Germany; 335 MW of PV was added in the U.S. in 2008, 293 MW of which came in the form of grid-connected installations. Despite the significant year-on-year growth, however, the share of global and U.S. electricity supply met with PV remains small, and annual PV additions are currently modest in the context of the overall electric system. The market for PV in the U.S. is driven by national, state, and local government incentives, including up-front cash rebates, production-based incentives, requirements that electricity suppliers purchase a certain amount of solar energy, and Federal and state tax benefits. These programs are, in part, motivated by the popular appeal of solar energy, and by the positive attributes of PV - modest environmental impacts, avoidance of fuel price risks, coincidence with peak electrical demand, and the location of PV at the point of use. Given the …
Date: October 5, 2009
Creator: Barbose, Galen L.; Wiser, Ryan; Peterman, Carla & Darghouth, Naim
Object Type: Report
System: The UNT Digital Library
2008 Nevada Test Site Annual Illness and Injury Surveillance Report (open access)

2008 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 epidemiologic surveillance activities that provide an early warning system for health problems among workers. The Illness and Injury Surveillance Program monitors illnesses and health conditions that result in an absence of workdays, occupational injuries and illnesses, and disabilities and deaths among current workers.
Date: October 5, 2009
Creator: United States. Department of Energy. Office of Health, Safety, and Security.
Object Type: Report
System: The UNT Digital Library
FINAL REPORT: Coupling Sorption to Soil Weathering During Reactive Transport: Impacts of Mineral Transformation and Sorbent Aging on Contaminant Speciation and Mobility (open access)

FINAL REPORT: Coupling Sorption to Soil Weathering During Reactive Transport: Impacts of Mineral Transformation and Sorbent Aging on Contaminant Speciation and Mobility

This project aimed for a predictive-mechanistic understanding of the coupling between mineral weathering and contaminant (Cs, Sr, I) transport/fate in caustic waste-impacted sediments. Based on our prior studies of model clay mineral systems, we postulated that contaminant uptake to Hanford sediments would reflect concurrent adsorption and co-precipitation effects. Our specific objectives were: (1) to assess the molecular-scale mechanisms responsible for time-dependent sequestration of contaminants (Cs, Sr and I) during penetration of waste-induced weathering fronts; (2) to determine the rate and extent of contaminant release from the sorbed state; (3) to develop a reactive transport model based on molecular mechanisms and macroscopic flow experiments [(1) and (2)] that simulates adsorption, aging, and desorption dynamics. Progress toward achieving each of these objectives is discussed in this Final Report.
Date: October 5, 2009
Creator: Mueller, Karl T; Chorover, John C; ODay, Peggy A; Um, Wooyong & Steefel, Carl I
Object Type: Report
System: The UNT Digital Library
Funnel cone for focusing intense ion beams on a target (open access)

Funnel cone for focusing intense ion beams on a target

We describe a funnel cone for concentrating an ion beam on a target. The cone utilizes the reflection characteristic of ion beams on solid walls to focus the incident beam andincrease beam intensity on target. The cone has been modeled with the TRIM code. A prototype has been tested and installed for use in the 350-keV K+ NDCX target chamber.
Date: October 5, 2009
Creator: Bieniosek, F.M.; Henestroza, E. & Ni, P.
Object Type: Article
System: The UNT Digital Library
Glass Property Data and Models for Estimating High-Level Waste Glass Volume (open access)

Glass Property Data and Models for Estimating High-Level Waste Glass Volume

This report describes recent efforts to develop glass property models that can be used to help estimate the volume of high-level waste (HLW) glass that will result from vitrification of Hanford tank waste. The compositions of acceptable and processable HLW glasses need to be optimized to minimize the waste-form volume and, hence, to save cost. A database of properties and associated compositions for simulated waste glasses was collected for developing property-composition models. This database, although not comprehensive, represents a large fraction of data on waste-glass compositions and properties that were available at the time of this report. Glass property-composition models were fit to subsets of the database for several key glass properties. These models apply to a significantly broader composition space than those previously publised. These models should be considered for interim use in calculating properties of Hanford waste glasses.
Date: October 5, 2009
Creator: Vienna, John D.; Fluegel, Alexander; Kim, Dong-Sang & Hrma, Pavel R.
Object Type: Report
System: The UNT Digital Library
Genetic Control or Repair and Adaptive Response to Low-Level DNA Damage (open access)

Genetic Control or Repair and Adaptive Response to Low-Level DNA Damage

Research was focused on how a single double-strand break - a model of low-dose ionizing radiation-induced DNA damage - could be studied in a simple model system, budding yeast. Breaks were induced in several different ways. We used the site-specific HO endonuclease to create a single DSB in all cells of the population so that its fate could be extensively analyzed genetically and molecularly. We also used two heterologous systems, the plant DS element and the Rag1/Rag2 proteins, to generate different types of DSBs, these containing hairpin ends that needed to be cleaved open before end-joining could take place. All three approaches yielded important new findings. We also extended our analysis of the Mre11 protein that plays key roles in both NHEJ and in homologous recombination. Finally we analyzed the poorly understood recombination events that were independent of the key recombination protein, Rad52. This line of inquiry was strongly motivated by the fact that vertebrate cells do not rely strongly on Rad52 for homologous recombination, so that some clues about alternative mechanisms could be gained by understanding how Rad52-independent recombination occurred. We found that the Mre11 complex was the most important element in Rad52-independent recombination.
Date: October 5, 2009
Creator: Haber, J. E.
Object Type: Report
System: The UNT Digital Library
Optical Model and Cross Section Uncertainties (open access)

Optical Model and Cross Section Uncertainties

Distinct minima and maxima in the neutron total cross section uncertainties were observed in model calculations using spherical optical potential. We found this oscillating structure to be a general feature of quantum mechanical wave scattering. Specifically, we analyzed neutron interaction with 56Fe from 1 keV up to 65 MeV, and investigated physical origin of the minima.We discuss their potential importance for practical applications as well as the implications for the uncertainties in total and absorption cross sections.
Date: October 5, 2009
Creator: Herman, M. W.; Pigni, M. T.; Dietrich, F. S. & Oblozinsky, P.
Object Type: Article
System: The UNT Digital Library
2003 Pantex Plant Annual Illness and Injury Surveillance Report, Revised September 2007 (open access)

2003 Pantex Plant Annual Illness and Injury Surveillance Report, Revised September 2007

Annual Illness and Injury Surveillance Program report for 2003 for the Pantex Plant. DOE is commited to assuring the health and safety of its workers. This includes the conduct of epidemiologic surveillance activities that provide an early warning system for health problems among workers. The IISP monitors illnesses and health conditions that result in an absence of workdays, occupational injuries and illnesses, and disabilities and deaths among current workers.
Date: October 5, 2007
Creator: United States. Department of Energy. Office of Illness and Injury Prevention Programs.
Object Type: Report
System: The UNT Digital Library
Scintillation and Luminescence Properties of Undoped and Cerium-doped LiGdCl4 and NaGdCl4 (open access)

Scintillation and Luminescence Properties of Undoped and Cerium-doped LiGdCl4 and NaGdCl4

We report the scintillation properties of the undoped and cerium-doped variations of LiGdCl4 and NaGdCl4. Powder samples of these materials exhibit significant scintillation under X-rays. The samples were synthesized by solid-state methods from a 1:1 molar ratio of lithium or sodium chloride and gadolinium chloride. Cerium trichloride was used as the dopant. The physical, optical, and scintillation properties of these materials were analyzed by powder X-ray diffraction, photoluminescence, X-ray excited luminescence, and pulsed X-ray luminosity measurements. Increases in light yields are observed as the concentration of cerium increases. The highest light yields occurred at 20 percent cerium doping for both compounds. At larger concentrations neither compound formed, indicating a breakdown of the lattice with the addition of large amounts of cerium cations. At 20 percent cerium, LiGdCl4 and NaGdCl4 display scintillation light 3.6 times and 2.2 times the light yield of the reference material, YAlO3:Ce3+, respectively. Both emit in the ranges of 340 ? 350 nm and 365 - 370 nm and display multiexponential decays with cerium-like decay components at 33 ns (LiGdCl4:Ce) and 26 ns (NaGdCl4:Ce).
Date: October 5, 2008
Creator: Porter-Chapman, Yetta D.; Bourret-Courchesne, Edith D.; Bizarri, Gregory; Weber, Marvin J. & Derenzo, Stephen E.
Object Type: Article
System: The UNT Digital Library
The radiative influence of aerosol effects on liquid-phase cumulusclouds based on sensitivity studies with two climate models (open access)

The radiative influence of aerosol effects on liquid-phase cumulusclouds based on sensitivity studies with two climate models

None
Date: October 5, 2005
Creator: Menon, Surabi & Rotstayn, Leon
Object Type: Article
System: The UNT Digital Library
2003 Savannah River Site Annual Illness and Injury Surveillance Report, Revised September 2007 (open access)

2003 Savannah River Site Annual Illness and Injury Surveillance Report, Revised September 2007

Annual Illness and Injury Surveillance Program report for 2003 for the Savannah River Site. DOE is commitment to assuring the health and safety of its workers includes the conduct of epidemiologic surveillance activities that provide an early warning system for health problems among workers. The report monitors illnesses and health conditions that result in an absence of workdays, occupational injuries and illnesses, and disabilities and deaths among current workers.
Date: October 5, 2007
Creator: United States. Department of Energy. Office of Illness and Injury Prevention Programs.
Object Type: Report
System: The UNT Digital Library
Pressure-Induced Electronic Spin Transition of Iron in Magnesiow?stite-(Mg,Fe)O (open access)

Pressure-Induced Electronic Spin Transition of Iron in Magnesiow?stite-(Mg,Fe)O

An electronic transition of iron in magnesiowuestite has been studied with synchrotron Moessbauer and X-ray emission spectroscopies under high pressures. Synchrotron Moessbauer studies show that the quadrupole splitting disappears and the isomer shift drops significantly across the spin-paring transition of iron in (Mg{sub 0.75},Fe{sub 0.25})O between 62 and 70 GPa, whereas X-ray emission spectroscopy of the Fe-K{sub {beta}} fluorescence lines in dilute (Mg{sub 0.95},Fe{sub 0.05})O also confirms that a high-spin to low-spin transition occurs between 46 GPa and 55 GPa. Based upon current results and percolation theory, we reexamine the high-pressure phase diagram of (Mg,Fe)O and find that iron-iron exchange interaction plays an important role in stabilizing the high-spin state of iron in FeO-rich (Mg,Fe)O.
Date: October 5, 2005
Creator: Lin, J. F.; Gavriliuk, A. G.; Struzhkin, V. V.; Jacobsen, S. D.; Sturhahn, W.; Hu, M. Y. et al.
Object Type: Article
System: The UNT Digital Library
US Activities in the Development of Plasma-Based X-ray Lasers (open access)

US Activities in the Development of Plasma-Based X-ray Lasers

None
Date: October 5, 2005
Creator: Dunn, J
Object Type: Article
System: The UNT Digital Library