Variational formulation of the Gardner's restacking algorithm (open access)

Variational formulation of the Gardner's restacking algorithm

The incompressibility of the phase flow of Hamiltonian wave-plasma interactions restrains the class of realizable wave-driven transformations of the particle distribution. After the interaction, the distribution remains composed of the original phase-space elements, or local densities, which are only rearranged (''restacked'') by the wave. A variational formalism is developed to study the corresponding limitations on the energy and momentum transfer. A case of particular interest is a toroidal plasma immersed in a dc magnetic field. The restacking algorithm by Gardner [Phys. Fluids 6, 839 (1963)] is formulated precisely. The minimum energy state for a plasma with a given current is determined
Date: April 26, 2004
Creator: Dodin, I. Y. & Fisch, N. J.
Object Type: Report
System: The UNT Digital Library
Sequencing Needs for Viral Diagnostics (open access)

Sequencing Needs for Viral Diagnostics

We built a system to guide decisions regarding the amount of genomic sequencing required to develop diagnostic DNA signatures, which are short sequences that are sufficient to uniquely identify a viral species. We used our existing DNA diagnostic signature prediction pipeline, which selects regions of a target species genome that are conserved among strains of the target (for reliability, to prevent false negatives) and unique relative to other species (for specificity, to avoid false positives). We performed simulations, based on existing sequence data, to assess the number of genome sequences of a target species and of close phylogenetic relatives (''near neighbors'') that are required to predict diagnostic signature regions that are conserved among strains of the target species and unique relative to other bacterial and viral species. For DNA viruses such as variola (smallpox), three target genomes provide sufficient guidance for selecting species-wide signatures. Three near neighbor genomes are critical for species specificity. In contrast, most RNA viruses require four target genomes and no near neighbor genomes, since lack of conservation among strains is more limiting than uniqueness. SARS and Ebola Zaire are exceptional, as additional target genomes currently do not improve predictions, but near neighbor sequences are urgently needed. …
Date: January 26, 2004
Creator: Gardner, S N; Lam, M; Mulakken, N J; Torres, C L; Smith, J R & Slezak, T
Object Type: Article
System: The UNT Digital Library
Acceleration of Polarized Protons in the AGS With Two Helical Partial Snakes. (open access)

Acceleration of Polarized Protons in the AGS With Two Helical Partial Snakes.

Acceleration of polarized protons in the energy range of 5 to 25 GeV is particularly difficult: the depolarizing resonances are strong enough to cause significant depolarization but full Siberian snakes cause intolerably large orbit excursions and are not feasible in the AGS since straight sections are too short. Recently, two helical partial snakes with double pitch design have been built and installed in the AGS. With careful setup of optics at injection and along the ramp, this combination can eliminate the intrinsic and imperfection depolarizing resonances encountered during acceleration. This paper presents the accelerator setup and preliminary results.
Date: June 26, 2006
Creator: Huang, H.; Ahrens, L. A.; Bai, M.; Bravar, A.; Brown, K.; Courant, E. D. et al.
Object Type: Article
System: The UNT Digital Library
The budding yeast silencing protein Sir1 is a functional component of centromeric chromatin (open access)

The budding yeast silencing protein Sir1 is a functional component of centromeric chromatin

None
Date: August 26, 2003
Creator: Sharp, Judith A.; Krawitz, Denise C.; Gardner, Kelly A.; Fox, Catherine A. & Kaufman, Paul D.
Object Type: Article
System: The UNT Digital Library
Chemical Technology Division Annual Report 2000. (open access)

Chemical Technology Division Annual Report 2000.

The Chemical Technology Division (CMT) is one of eight engineering research divisions within Argonne National Laboratory (ANL), one of the U.S. government's oldest and largest research laboratories. The University of Chicago oversees the laboratory on behalf of the U.S. Department of Energy (DOE). Argonne's mission is to conduct basic scientific research, to operate national scientific facilities, to enhance the nation's energy resources, and to develop better ways to manage environmental problems. Argonne has the further responsibility of strengthening the nation's technology base through developing industrial technology and transferring that technology to industry. The Chemical Technology Division is a diverse early-stage engineering organization, specializing in the treatment of spent nuclear fuel, development of advanced power sources, and management of both high- and low-level nuclear wastes. Although this work is often indistinguishable from basic research, our efforts are directed toward the practical devices and processes that are covered by ANL's mission. Additionally, the Division operates the Analytical Chemistry Laboratory, which provides a broad range of analytical services to ANL and other organizations. The Division is multi-disciplinary. Its people have formal training as ceramists; physicists; material scientists; electrical, mechanical, chemical, and nuclear engineers; and chemists. They have experience working in academia, urban planning, …
Date: April 26, 2001
Creator: Lewis, D.; Gay, E. C.; Miller, J. F.; Einziger, R. E. & Green, D. W.
Object Type: Report
System: The UNT Digital Library
Solid State Division Progress Report for Period Ending September 30, 1999 (open access)

Solid State Division Progress Report for Period Ending September 30, 1999

This report covers research progress in the Solid State Division from April 1, 1997, through September 30, 1999. During this period, the division conducted a broad, interdisciplinary materials research program in support of Department of Energy science and technology missions. The report includes brief summaries of research activities in condensed matter theory, neutron scattering, synthesis and characterization of materials, ion beam and laser processing, and the structure of solids and surfaces. An addendum includes listings of division publications and professional activities. Over the past two years, a number of important infrastructure improvements that will provide significant new research opportunities and unique capabilities for the division in neutron scattering and synchrotron x-ray research, electron microscopy, nanostructure fabrication, and theory have been pursued. A major upgrade of neutron scattering capabilities at the High Flux Isotope Reactor (HFIR), including a high-performance cold source, new beam lines and guides, and new and upgraded instrumentation, is under way. These upgrades, together with the proposed Spallation Neutron Source at ORNL, will provide the nation with unsurpassed capabilities worldwide in neutron scattering. The division is also involved in the development of two synchrotron beam lines at the Advanced Photon Source at Argonne National Laboratory, an upgrade of …
Date: February 26, 2001
Creator: Cooke, J.F.
Object Type: Report
System: The UNT Digital Library
Approximate Integrals of rf-driven Particle Motion in Magnetic Field (open access)

Approximate Integrals of rf-driven Particle Motion in Magnetic Field

For a particle moving in nonuniform magnetic field under the action of an rf wave, ponderomotive effects result from rf-driven oscillations nonlinearly coupled with Larmor rotation. Using Lagrangian and Hamiltonian formalism, we show how, despite this coupling, two independent integrals of the particle motion are approximately conserved. Those are the magnetic moment of free Larmor rotation and the quasi-energy of the guiding center motion parallel to the magnetic field. Under the assumption of non-resonant interaction of the particle with the rf field, these integrals represent adiabatic invariants of the particle motion.
Date: April 26, 2004
Creator: Dodin, I. Y. & Fisch, N. J.
Object Type: Report
System: The UNT Digital Library
Diagnostic evaluation of a multiplexed RT-PCR microsphere array assay for the detection of foot-and-mouth disease virus and look-alike disease viruses (open access)

Diagnostic evaluation of a multiplexed RT-PCR microsphere array assay for the detection of foot-and-mouth disease virus and look-alike disease viruses

A high-throughput multiplexed assay was developed for the differential laboratory diagnosis of foot-and-mouth disease virus (FMDV) from viruses which cause clinically similar diseases of livestock. This assay simultaneously screens for five RNA and two DNA viruses using multiplexed reverse transcription PCR (mRT-PCR) amplification coupled with a microsphere hybridization array and flow-cytometric detection. Two of the seventeen primer-probe sets included in this multiplex assay were adopted from previously characterized real-time RT-PCR (rRT-PCR) assays for FMDV. The diagnostic accuracy of the mRT-PCR was evaluated using 287 field samples, including 248 (true positive n= 213, true negative n=34) from suspect cases of foot-and-mouth disease collected from 65 countries between 1965 and 2006 and 39 true negative samples collected from healthy animals. The mRT-PCR assay results were compared with two singleplex rRT-PCR assays, using virus isolation with antigen-ELISA as the reference method. The diagnostic sensitivity of the mRT-PCR assay for FMDV was 93.9% [95% C.I. 89.8-96.4%], compared to 98.1% [95% C.I. 95.3-99.3%] for the two singleplex rRT-PCR assays used in combination. In addition, the assay could reliably differentiate between FMDV and other vesicular viruses such as swine vesicular disease virus and vesicular exanthema of swine virus. Interestingly, the mRT-PCR detected parapoxvirus (n=2) and bovine …
Date: July 26, 2007
Creator: Hindson, B J; Reid, S M; Baker, B R; Ebert, K; Ferris, N P; Bentley Tammero, L F et al.
Object Type: Article
System: The UNT Digital Library
Modeled Neutron Induced Nuclear Reaction Cross Sections for Radiochemistry in the region of Iriduim and Gold (open access)

Modeled Neutron Induced Nuclear Reaction Cross Sections for Radiochemistry in the region of Iriduim and Gold

We have developed a set of modeled nuclear reaction cross sections for use in radiochemical diagnostics. Systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron induced nuclear reaction cross sections for targets ranging from osmium (Z = 76) to gold (Z = 79). Of particular interest are the cross sections on Ir and Au including reactions on isomeric targets.
Date: February 26, 2008
Creator: Hoffman, R. D.; Dietrich, F. S.; Kelley, K.; Escher, J.; Bauer, R. & Mustafa, M. G.
Object Type: Report
System: The UNT Digital Library
300 Area Uranium Leach and Adsorption Project (open access)

300 Area Uranium Leach and Adsorption Project

The objective of this study was to measure the leaching and adsorption characteristics of uranium in six near-surface sediment samples collected from the 300 Area of the Hanford Site. Scanning electron micrographs of the samples showed that the uranium contamination in the sediments is most likely present as co-precipitates and/or discrete uranium particles. Molecular probe techniques also confirm the presence of crystalline discrete uranium bearing phases. In all cases, the uranium is present as oxidized uranium (uranyl [U(VI)]). Results from the column leach tests showed that uranium leaching did not follow a constant solubility paradigm. Four of the five contaminated sediments showed a large near instantaneous release of a few percent of the total uranium followed by a slower continual release. Steady-state uranium leachate concentrations were never measured and leaching characteristics and trends were not consistent among the samples. Dissolution kinetics were slow, and the measured leach curves most likely represent a slow kinetically controlled desorption or dissolution paradigm. Batch adsorption experiments were performed to investigate the effect of pH and uranium and carbonate solution concentrations on uranium adsorption onto the uncontaminated sediment. Uranium adsorption Kd values ranged from 0 to > 100 ml/g depending on which solution parameter was …
Date: November 26, 2002
Creator: Serne, R. Jeffrey; Brown, Christopher F.; Schaef, Herbert T.; Pierce, Eric M.; Lindberg, Michael J.; Wang, Zheming et al.
Object Type: Report
System: The UNT Digital Library
The Murmansk Initiative - RF: Acceptance Testing (open access)

The Murmansk Initiative - RF: Acceptance Testing

The Murmansk Initiative-RF (MI) was conceived to provide the Russian Federation (RF) with the capacity to manage low-level liquid radioactive waste (LLRW) and comply with the requirements of the London Convention that prohibit ocean dumping. The trilateral project among Norway, the RF, and the United States of America (U.S.) began in 1994 and was the first to utilize exclusively Russian subcontractors to upgrade and expand an existing LLRW treatment plant on the premises of RTP Atomflot in Murmansk, Russia. The project moved quickly through the design phase. Progress during the construction phase was somewhat slower because of difficulties with acquisition of hardware, inexperience with automated instrumentation and control equipment, and unexpected design changes in the cementation unit. The project advanced into the test-operation phase, which is currently underway, in June 2001. Initial runs with liquid waste have revealed that procedures for unloading spent ion-exchange sorbents could be improved and that sludges formed during removal of alkaline-earth metals should be compacted in order for the facility to operate at its full potential. Resolution of these issues is expected within the next few months.
Date: February 26, 2002
Creator: Czajkowski, C.; Wester, D. W.; Dyer, R. S.; Soerlie, A. A.; Moller, B. & Barnes, E.
Object Type: Article
System: The UNT Digital Library
FEASIBILITY ANALYSIS FOR INSTALLING A CIRCULATING FLUIDIZED BED BOILER FOR COFIRING MULTIPLE BIOFUELS AND OTHER WASTES WITH COAL AT PENN STATE UNIVERSITY (open access)

FEASIBILITY ANALYSIS FOR INSTALLING A CIRCULATING FLUIDIZED BED BOILER FOR COFIRING MULTIPLE BIOFUELS AND OTHER WASTES WITH COAL AT PENN STATE UNIVERSITY

The Pennsylvania State University, utilizing funds furnished by the U.S. Department of Energy's Biomass Power Program, investigated the installation of a state-of-the-art circulating fluidized bed boiler at Penn State's University Park campus for cofiring multiple biofuels and other wastes with coal, and developing a test program to evaluate cofiring biofuels and coal-based feedstocks. The study was performed using a team that included personnel from Penn State's Energy Institute, Office of Physical Plant, and College of Agricultural Sciences; Foster Wheeler Energy Services, Inc.; Foster Wheeler Energy Corporation; Parsons Energy and Chemicals Group, Inc.; and Cofiring Alternatives. The activities included assessing potential feedstocks at the University Park campus and surrounding region with an emphasis on biomass materials, collecting and analyzing potential feedstocks, assessing agglomeration, deposition, and corrosion tendencies, identifying the optimum location for the boiler system through an internal site selection process, performing a three circulating fluidized bed (CFB) boiler design and a 15-year boiler plant transition plan, determining the costs associated with installing the boiler system, developing a preliminary test program, determining the associated costs for the test program, and exploring potential emissions credits when using the biomass CFB boiler.
Date: March 26, 2003
Creator: Miller, Bruce G.; Miller, Sharon Falcone; Cooper, Robert; Gaudlip, John; Lapinsky, Matthew; McLaren, Rhett et al.
Object Type: Report
System: The UNT Digital Library
Development of Mercury and Hydrogen Chloride Emission Monitors for Coal Gasifiers (open access)

Development of Mercury and Hydrogen Chloride Emission Monitors for Coal Gasifiers

The gas conditioning issues involved with coal gasification streams are very complex and do not have simple solutions. This is particularly true in view of the fact that the gas conditioning system must deal with tars, high moisture contents, and problems with NH{sub 3} without affecting low ppb levels of Hg, low levels (low ppm or less) of HCl, or the successful operation of conditioner components and analytical systems. Those issues are far from trivial. Trying to develop a non-chemical system for gas conditioning was very ambitious in view of the difficult sampling environment and unique problems associated with coal gasification streams. Although a great deal was learned regarding calibration, sample transport, instrumentation options, gas stream conditioning, and CEM design options, some challenging issues still remain. Sample transport is one area that is often not adequately considered. Because of the gas stream composition and elevated temperatures involved, special attention will need to be given to the choice of materials for the sample line and other plumbing components. When using gas stream oxidation, there will be sample transport regions under oxidizing as well as reducing conditions, and each of those regions will require different materials of construction for sample transport. The …
Date: February 26, 2001
Creator: Norton, G.; Eckels, D. & Chriswell, C.
Object Type: Report
System: The UNT Digital Library
Spectroscopic Confirmation of A Radio-Selected Galaxy Overdensity at z = 1.11 (open access)

Spectroscopic Confirmation of A Radio-Selected Galaxy Overdensity at z = 1.11

We report the discovery of a galaxy overdensity at z = 1.11 associated with the z = 1.110 high-redshift radio galaxy MG 0442+0202. The group, CL 0442+0202, was found in a near-infrared survey of z > 1 radio galaxies undertaken to identify spatially-coincident regions with a high density of objects red in I - K' color, typical of z > 1 elliptical galaxies. Spectroscopic observations from the Keck I telescope reveal five galaxies within 35'' of MG 0442+0202 at 1.10 < z < 1.11. These member galaxies have broad-band colors and optical spectra consistent with passively-evolving elliptical galaxies formed at high redshift. Archival ROSAT observations reveal a 3{sigma} detection of soft X-ray emission coincident with CL 0442+0202 at a level five times greater than expected for the radio galaxy. These data are suggestive of a rich galaxy cluster and inspired a 45 ks Chandra X-Ray Observatory observation. As expected, the radio galaxy is unresolved to Chandra, but is responsible for approximately half of the observed X-ray flux. The remaining ROSAT flux is resolved into four point sources within 15'' of the radio galaxy, corresponding to a surface density two orders of magnitude higher than average for X-ray sources at these …
Date: February 26, 2004
Creator: Stanford, S; Stern, D; Holden, B & Spinrad, H
Object Type: Article
System: The UNT Digital Library
Studies of Correlated-Electron Systems in High Magnetic Fields and at High Pressures (open access)

Studies of Correlated-Electron Systems in High Magnetic Fields and at High Pressures

None
Date: March 26, 2008
Creator: Cornelius, Dr. Andrew
Object Type: Report
System: The UNT Digital Library
Community Correspondence – Individual Letters regarding the 130th Airlift Wing and Yeager Air Guard (open access)

Community Correspondence – Individual Letters regarding the 130th Airlift Wing and Yeager Air Guard

Community Correspondence – Individual letters from concerned citizens regarding the closure of the 130th Airlift Wing, Air National Guard Unit at Yeager Airport in Charleston West Virginia
Date: July 26, 2005
Creator: unknown
Object Type: Letter
System: The UNT Digital Library
High concentration suspended sediment measurments using acontinuous fiber optic in-stream transmissometer (open access)

High concentration suspended sediment measurments using acontinuous fiber optic in-stream transmissometer

Suspended sediment loads mobilized during high flow periods in rivers and streams are largely uncharacterized. In smaller and intermittent streams, a large storm may transport a majority of the annual sediment budget. Therefore monitoring techniques that can measure high suspended sediment concentrations at semi-continuous time intervals are needed. A Fiber optic In-stream Transmissometer (FIT) is presented for continuous measurement of high concentration suspended sediment in storm runoff. FIT performance and precision were demonstrated to be reasonably good for suspended sediment concentrations up to 10g/L. The FIT was compared to two commercially available turbidity devices and provided better precision and accuracy at both high and low concentrations. Both turbidity devices were unable to collect measurements at concentrations greater than 4 g/L. The FIT and turbidity measurements were sensitive to sediment particle size. Particle size dependence of transmittance and turbidity measurement poses the greatest problem for calibration to suspended sediment concentration. While the FIT was demonstrated to provide acceptable measurements of high suspended sediment concentrations, approaches to real-time suspended sediment detection need to address the particle size dependence in concentration measurements.
Date: May 26, 2004
Creator: Campbell, Chris G.; Laycak, Danny T.; Hoppes, William; Tran,Nguyen T. & Shi, Frank G.
Object Type: Article
System: The UNT Digital Library
Navy-Marine Corps Amphibious and Maritime Prepositioning Ship Programs: Background and Oversight Issues for Congress (open access)

Navy-Marine Corps Amphibious and Maritime Prepositioning Ship Programs: Background and Oversight Issues for Congress

The Navy is proposing to maintain in coming years a Navy with 31 amphibious ships and an additional squadron of 14 Maritime Prepositioning Force (Future), or MPF(F), ships. The squadron is intended to implement a new concept called sea basing, under which forces would be staged at sea and used to conduct expeditionary operations ashore with little or no reliance on nearby land bases. Potential oversight issues for Congress include the amphibious-ship force-level goal, the potential affordability and cost-effectiveness of the sea basing concept, and Navy and Marine Corps coordination with other services in developing the concept.
Date: July 26, 2006
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library
Navy-Marine Corps Amphibious and Maritime Prepositioning Ship Programs: Background and Oversight Issues for Congress (open access)

Navy-Marine Corps Amphibious and Maritime Prepositioning Ship Programs: Background and Oversight Issues for Congress

None
Date: July 26, 2006
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library
Navy-Marine Corps Amphibious and Maritime Prepositioning Ship Programs: Background and Oversight Issues for Congress (open access)

Navy-Marine Corps Amphibious and Maritime Prepositioning Ship Programs: Background and Oversight Issues for Congress

None
Date: July 26, 2006
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library
MAPPING FLOW LOCALIZATION PROCESSES IN DEFORMATION OF IRRADIATED REACTOR STRUCTURAL ALLOYS - FINAL REPORT. Nuclear Energy Research Initiative Program No. MSF99-0072. Period: August 1999 through September 2002. (ORNL/TM-2003/63) (open access)

MAPPING FLOW LOCALIZATION PROCESSES IN DEFORMATION OF IRRADIATED REACTOR STRUCTURAL ALLOYS - FINAL REPORT. Nuclear Energy Research Initiative Program No. MSF99-0072. Period: August 1999 through September 2002. (ORNL/TM-2003/63)

Metals that can sustain plastic deformation homogeneously throughout their bulk tend to be tough and malleable. Often, however, if a metal has been hardened it will no longer deform uniformly. Instead, the deformation occurs in narrow bands on a microscopic scale wherein stresses and strains become concentrated in localized zones. This strain localization degrades the mechanical properties of the metal by causing premature plastic instability failure or by inducing the formation of cracks. Irradiation with neutrons hardens a metal and makes it more prone to deformation by strain localization. Although this has been known since the earliest days of radiation damage studies, a full measure of the connection between neutron irradiation hardening and strain localization is wanting, particularly in commercial alloys used in the construction of nuclear reactors. Therefore, the goal of this project is to systematically map the extent of involvement of strain localization processes in plastic deformation of three reactor alloys that have been neutron irradiated. The deformation processes are to be identified and related to changes in the tensile properties of the alloys as functions of neutron fluence (dose) and degree of plastic strain. The intent is to define the role of strain localization in radiation embrittlement …
Date: September 26, 2003
Creator: Farrell, K.
Object Type: Report
System: The UNT Digital Library
[Navy-Marine Corps Amphibious and Maritime Prepositioning Ship Programs: Background and Oversight Issues for Congress, January 26, 2007] (open access)

[Navy-Marine Corps Amphibious and Maritime Prepositioning Ship Programs: Background and Oversight Issues for Congress, January 26, 2007]

None
Date: January 26, 2007
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library
Intelligent Monitoring System with High Temperature Distributed Fiberoptic Sensor for Power Plant Combustion Processes (open access)

Intelligent Monitoring System with High Temperature Distributed Fiberoptic Sensor for Power Plant Combustion Processes

The objective of the proposed work is to develop an intelligent distributed fiber optical sensor system for real-time monitoring of high temperature in a boiler furnace in power plants. Of particular interest is the estimation of spatial and temporal distributions of high temperatures within a boiler furnace, which will be essential in assessing and controlling the mechanisms that form and remove pollutants at the source, such as NOx. The basic approach in developing the proposed sensor system is three fold: (1) development of high temperature distributed fiber optical sensor capable of measuring temperatures greater than 2000 C degree with spatial resolution of less than 1 cm; (2) development of distributed parameter system (DPS) models to map the three-dimensional (3D) temperature distribution for the furnace; and (3) development of an intelligent monitoring system for real-time monitoring of the 3D boiler temperature distribution. Under Task 1, we have set up a dedicated high power, ultrafast laser system for fabricating in-fiber gratings in harsh environment optical fibers, successfully fabricated gratings in single crystal sapphire fibers by the high power laser system, and developed highly sensitive long period gratings (lpg) by electric arc. Under Task 2, relevant mathematical modeling studies of NOx formation in …
Date: September 26, 2006
Creator: Lee, Kwang Y.; Yin, Stuart S. & Boehman, Andre
Object Type: Report
System: The UNT Digital Library
Advanced Materials for PEM-Based Fuel Cell Systems (open access)

Advanced Materials for PEM-Based Fuel Cell Systems

Proton exchange membrane fuel cells (PEMFCs) are quickly becoming attractive alternative energy sources for transportation, stationary power, and small electronics due to the increasing cost and environmental hazards of traditional fossil fuels. Two main classes of PEMFCs include hydrogen/air or hydrogen/oxygen fuel cells and direct methanol fuel cells (DMFCs). The current benchmark membrane for both types of PEMFCs is Nafion, a perfluorinated sulfonated copolymer made by DuPont. Nafion copolymers exhibit good thermal and chemical stability, as well as very high proton conductivity under hydrated conditions at temperatures below 80 degrees C. However, application of these membranes is limited due to their high methanol permeability and loss of conductivity at high temperatures and low relative humidities. These deficiencies have led to the search for improved materials for proton exchange membranes. Potential PEMs should have good thermal, hydrolytic, and oxidative stability, high proton conductivity, selective permeability, and mechanical durability over long periods of time. Poly(arylene ether)s, polyimides, polybenzimidazoles, and polyphenylenes are among the most widely investigated candidates for PEMs. Poly(arylene ether)s are a promising class of proton exchange membranes due to their excellent thermal and chemical stability and high glass transition temperatures. High proton conductivity can be achieved through post-sulfonation of poly(arylene …
Date: October 26, 2005
Creator: McGrath, James E.; Baird, Donald G. & Spakovsky, Michael von
Object Type: Report
System: The UNT Digital Library