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0.52eV Quaternary InGaAsSb Thermophotovoltaic Diode Technology

Description: Thermophotovoltaic (TPV) diodes fabricated from 0.52eV lattice-matched InGaAsSb alloys are grown by Metal Organic Vapor Phase Epitaxy (MOVPE) on GaSb substrates. 4cm{sup 2} multi-chip diode modules with front-surface spectral filters were tested in a vacuum cavity and attained measured efficiency and power density of 19% and 0.58 W/cm{sup 2} respectively at operating at temperatures of T{sub radiator} = 950 C and T{sub diode} = 27 C. Device modeling and minority carrier lifetime measurements of double heterostructure lifetime specimens indicate that diode conversion efficiency is limited predominantly by interface recombination and photon energy loss to the GaSb substrate and back ohmic contact. Recent improvements to the diode include lattice-matched p-type AlGaAsSb passivating layers with interface recombination velocities less than 100 cm/s and new processing techniques enabling thinned substrates and back surface reflectors. Modeling predictions of these improvements to the diode architecture indicate that conversion efficiencies from 27-30% and {approx}0.85 W/cm{sup 2} could be attained under the above operating temperatures.
Date: June 9, 2004
Creator: Dashiell, M. W.; Beausang, J. F.; Nichols, G.; Depoy, D. M.; Danielson, L. R.; Ehsani, H. et al.
open access

1.5-GEV FFAG ACCELERATOR AS INJECTOR TO THE BNL-AGS.

Description: A 1.5-GeV Fixed-Field Alternating-Gradient (FFAG) proton Accelerator is being studied as a new injector to the Alternating-Gradient Synchrotron (AGS) of Brookhaven National Laboratory (BNL). The major benefit is that it would considerably shorten the overall AGS acceleration cycle, and, consequently, may yield to an improvement of beam stability, intensity and size. The AGS-FFAG will also facilitate the proposed upgrade of the AGS facility toward a 1-MW average proton beam power at the top energy of 28 GeV. This paper describes the FFAG design for acceleration of protons from 400 MeV to 1.5 GeV, with the same circumference of the AGS, and entirely housed in the AGS tunnel.
Date: July 5, 2004
Creator: Ruggiero, A. G.; Blaskiewicz, M.; Trbojevic, D.; Tsoupas, N. & Zhang, W.
open access

01-ERD-111 - The Development of Synthetic High Affinity Ligands

Description: The aim of this project was to develop Synthetic High-Affinity Ligands (SHALs), which bind with high affinity and specificity to proteins of interest for national security and cancer therapy applications. The aim of producing synthetic ligands for sensory devices as an alternative to antibody-based detection assays and therapeutic agents is to overcome the drawbacks associated with antibody-based in next-generation sensors and systems. The focus area of the project was the chemical synthesis of the SHALs. The project concentrated on two different protein targets. (a) The C fragment of tetanus and botulinum toxin, potential biowarfare agents. A SHAL for tetanus or botulinum toxin would be incorporated into a sensory device for the toxins. (b) HLA-DR10, a protein found in high abundance on the surface of Non-Hodgkins Lymphoma. A SHAL specific to a tumor marker, labeled with a radionuclide, would enable the targeted delivery of radiation therapy to metastatic disease. The technical approach used to develop a SHAL for each protein target will be described in more detail below. However, in general, the development of a SHAL requires a combination of computational modeling techniques, modern nuclear magnetic resonance spectroscopy (NMR) and synthetic chemistry.
Date: February 5, 2004
Creator: Perkins, J; Balhorn, R; Cosman, M; Lightstone, F & Zeller, L
open access

A 1-Joule laser for a 16-fiber injection system

Description: A 1-J laser was designed to launch light down 16, multi-mode fibers (400-{micro}m-core dia.). A diffractive-optic splitter was designed in collaboration with Digital Optics Corporation (DOC), and was delivered by DOC. Using this splitter, the energy injected into each fiber varied <1%. The spatial profile out of each fiber was such that there were no ''hot spots,'' a flyer could successfully be launched and a PETN pellet could be initiated. Preliminary designs of the system were driven by system efficiency where a pristine TEM{sub 00} laser beam would be required. The laser is a master oscillator, power amplifier (MOPA) consisting of a 4-mm-dia. Nd:YLF rod in the stable, q-switched oscillator and a 9.5-mm-dia. Nd:YLF rod in the double-passed amplifier. Using a TEM{sub 00} oscillator beam resulted in excellent transmission efficiencies through the fibers at lower energies but proved to be quite unreliable at higher energies, causing premature fiber damage, flyer plate rupture, stimulated Raman scattering (SRS), and stimulated Brillouin scattering (SBS). Upon further investigation, it was found that both temporal and spatial beam formatting of the laser were required to successfully initiate the PETN. Results from the single-mode experiments, including fiber damage, SRS and SBS losses, will be presented. In addition, results showing the improvement that can be obtained by proper laser beam formatting will also be presented.
Date: April 6, 2004
Creator: Honig, J
open access

1 Outreach, Education and Domestic Market Enhancement 2 Export Promotion and Assistance

Description: Geothermal Energy Association supports the US geothermal industry in its efforts to bring more clean geothermal energy on-line throughout the world. Activities designed to accomplish this goal include: (1) developing and maintaining data bases, web pages, (2) commissioning of special studies and reports, (3) preparing, printing and distributing brochures and newsletters, (4) developing exhibits and displays, and participating in trade shows, (5) designing, producing and disseminating audio-video materials, (6) monitoring and coordinating programs carried out by US DOE and other Federal agencies, (7) holding workshops to facilitate communication between researchers and industry and to encourage their recognition of emerging markets for geothermal technology, (8) attending conferences, making speeches and presentation, and otherwise interacting with environmental and other renewable energy organizations and coalitions, (9) hosting events in Washington, DC and other appropriate locations to educate Federal, State and local representatives, environmental groups, the news media, and other about the status and potential of geothermal energy, (10) conducting member services such as the preparation and distribution of a member newsletter related to operating and maintaining s useful and viable association, and (11) performing similar kinds of activities designed to inform others about geothermal energy. The activities of the export promotion aim to assist industry in accomplishing the goal of successfully penetrating and developing energy in country with existing geothermal resources and a desire to develop them. Activities including in export promotion are: (1)needs analysis and assessment involve monitoring the progress of developing markets and projects overseas and working with US industry to determine what future activities by GEA would be of greatest assistance, (2) outreach includes the preparation and dissemination of brochures and videos for foreign professionals, officials and decision-makers as well as presentations of information of the geothermal technology and the capabilities of the US geothermal industry, (3) Market conditioning involves …
Date: March 15, 2004
Creator: Geothermal Energy Association
open access

2-D Imaging of Electron Temperature in Tokamak Plasmas

Description: By taking advantage of recent developments in millimeter wave imaging technology, an Electron Cyclotron Emission Imaging (ECEI) instrument, capable of simultaneously measuring 128 channels of localized electron temperature over a 2-D map in the poloidal plane, has been developed for the TEXTOR tokamak. Data from the new instrument, detailing the MHD activity associated with a sawtooth crash, is presented.
Date: July 8, 2004
Creator: Munsat, T.; Mazzucato, E.; Park, H.; Domier, C. W.; Johnson, M.; Luhmann, N. C. Jr. et al.
open access

2-MV electrostatic quadrupole injector for heavy-ion fusion

Description: High current and low emittance are principal requirements for heavy-ion injection into a linac driver for inertial fusion energy. An electrostatic quadrupole (ESQ) injector is capable of providing these high charge density and low emittance beams. We have modified the existing 2-MV Injector to reduce beam emittance and to double the pulse length. We characterize the beam delivered by the modified injector to the High Current Transport Experiment (HCX) and the effects of finite rise time of the extraction voltage pulse in the diode on the beam head. We demonstrate techniques for mitigating aberrations and reducing beam emittance growth in the injector.
Date: November 10, 2004
Creator: Bieniosek, F. M.; Celata, C. M.; Henestroza, E.; Kwan, J. W.; Prost, L. & Seidl, P. A.
open access

3-D Characterization of the Structure of Paper and Paperboard and Their Application to Optimize Drying and Water Removal Processes and End-Use Applications

Description: The three dimensional structure of paper materials plays a critical role in the paper manufacturing process especially via its impact on the transport properties for fluids. Dewatering of the wet web, pressing and drying will benefit from knowledge of the relationships between the web structure and its transport coefficients. The structure of the pore space within a paper sheet is imaged in serial sections using x-ray micro computed tomography. The three dimensional structure is reconstructed from these sections using digital image processing techniques. The structure is then analyzed by measuring traditional descriptors for the pore space such as specific surface area and porosity. A sequence of microtomographs was imaged at approximately 2 m intervals and the three-dimensional pore-fiber structure was reconstructed. The pore size distributions for both in-plane as well as transverse pores were measured. Significant differences in the in-plane (XY) and the transverse directions in pore characteristics are found and may help partly explain the different liquid and vapor transport properties in the in-plane and transverse directions. Results with varying sheet structures compare favorably with conventional mercury intrusion porosimetry data. Interestingly, the transverse pore structure appears to be more open with larger pore size distribution compared to the in plane pore structure. This may help explain the differences in liquid and vapor transport through the in plane and transverse structures during the paper manufacturing process and during end-use application. Comparison of Z-directional structural details of hand sheet and commercially made fine paper samples show a distinct difference in pore size distribution both in the in-plane and transverse direction. Method presented here may provide a useful tool to the papermaker to truly engineer the structure of paper and board tailored to specific end-use applications. The difference in surface structure between the top and bottom sides of the porous material, i.e. …
Date: August 29, 2004
Creator: Shri Ramaswamy, University of Minnesota & B.V. Ramarao, State University of New York
open access

3-D Seismic Experimentation and Advanced Processing/Inversion Development for Investigations of the Shallow Subsurface

Description: Under ER63662, 3-D Seismic Experimentation and Advanced Processing/Inversion Development for Investigations of the Shallow Subsurface, we have completed a number of subprojects associated with the Hill Air Force Base (HAFB) high resolution 3-D reflection/tomography dataset.
Date: December 1, 2004
Creator: Levander, Alan R.
open access

3-D Thermal Evaluations for a Fueled Experiment in the Advanced Test Reactor

Description: The DOE Advanced Fuel Cycle Initiative and Generation IV reactor programs are developing new fuel types for use in the current Light Water Reactors and future advanced reactor concepts. The Advanced Gas Reactor program is planning to test fuel to be used in the Next Generation Nuclear Plant (NGNP) nuclear reactor. Preliminary information for assessing performance of the fuel will be obtained from irradiations performed in the Advanced Test Reactor large ''B'' experimental facility. A test configuration has been identified for demonstrating fuel types typical of gas cooled reactors or fast reactors that may play a role in closing the fuel cycle or increasing efficiency via high temperature operation Plans are to have 6 capsules, each containing 12 compacts, for the test configuration. Each capsule will have its own temperature control system. Passing a helium-neon gas through the void regions between the fuel compacts and the graphite carrier and between the graphite carrier and the capsule wall will control temperature. This design with three compacts per axial level was evaluated for thermal performance to ascertain the temperature distributions in the capsule and test specimens with heating rates that encompass the range of initial heat generation rates.
Date: October 6, 2004
Creator: Ambrosek, Richard G.; Chang, Gray S. & Utterbeck, Debby J.
open access

3-D Thermal Evaluations for a Fueled Experiment in the Advanced Test Reactor

Description: The DOE Advanced Fuel Cycle Initiative and Generation IV reactor programs are developing new fuel types for use in the current Light Water Reactors and future advanced reactor concepts. The Advanced Gas Reactor program is planning to test fuel to be used in the Next Generation Nuclear Plant (NGNP) nuclear reactor. Preliminary information for assessing performance of the fuel will be obtained from irradiations performed in the Advanced Test Reactor large “B” experimental facility. A test configurations has been identified for demonstrating fuel types typical of gas cooled reactors or fast reactors that may play a role in closing the fuel cycle or increasing efficiency via high temperature operation Plans are to have 6 capsules, each containing 12 compacts, for the test configuration. Each capsule will have its own temperature control system. Passing a helium-neon gas through the void regions between the fuel compacts and the graphite carrier and between the graphite carrier and the capsule wall will control temperature. This design with three compacts per axial level was evaluated for thermal performance to ascertain the temperature distributions in the capsule and test specimens with heating rates that encompass the range of initial heat generation rates.
Date: October 1, 2004
Creator: Ambrosek, Richard; Chang, Gray & Utterbeck, Debra
open access

9/11 and Terrorist Travel: Staff Report of the National Commission on Terrorist Attacks Upon the United States

Description: Report of the National Commission on Terrorist Attacks Upon the United States (9-11 Commission) describing research into the events of September 11, 2001. It contains the Commission's findings based on the thousands of documents and hundreds of interviews collected during the course of the investigations.
Date: August 21, 2004
Creator: Eldridge, Thomas R.; Ginsburg, Susan; Hempel, Walter T., II; Kephart, Janice L. & Moore, Kelly
open access

The 9/11 Commission and a National Counterterrorism Center: Issues and Options for Congress

Description: This report examines a number of issues as Congress considers codification of an NCTC. One issue is whether the centralization remedy the commission has recommended fits the problems associated specifically with the 9/11 intelligence failure, and perhaps more broadly, the systematic maladies affecting the Intelligence Community. There are at least four options for congressional consideration: (1) NCTC with intelligence and operational planning duties, (2) NCTC restricted to an intelligence role, (3) NCTC restricted to an operational planning role, and (4) status quo plus-viewing the newly forming collected entity as a pilot potential NCTC. As one of its 41 recommendations, the 9/11 Commission recommended the creation of a National Counterterroism Center (NCTC).
Date: October 22, 2004
Creator: Masse, Todd
open access

The 9/11 Commission and a National Counterterrorism Center: Issues and Options for Congress

Description: From Summary: "This report, which will be updated, examines a number of issues as Congress considers codification of an NCTC. One issue is whether the centralization remedy the commission has recommended fits the problems associated specifically with the 9/11 intelligence failure, and perhaps more broadly, the systematic maladies affecting the Intelligence Community. There are at least four options for congressional consideration: (1) NCTC with intelligence and operational planning duties, (2) NCTC restricted to an intelligence role, (3) NCTC restricted to an operational planning role, and (4) status quo plus-viewing the newly forming collected entity as a pilot potential NCTC. As one of its 41 recommendations, the 9/11 Commission recommended the creation of a National Counterterroism Center (NCTC)."
Date: October 6, 2004
Creator: Masse, Todd
open access

9/11 Commission: Current Legislative Proposals for U.S. Immigration Law and Policy

Description: This report briefly discusses some of the major immigration areas under consideration in comprehensive reform proposals suggested by the 9/11 Commission, including asylum, biometric tracking systems, border security, document security, exclusion, immigration enforcement, and visa issuances. It refers to other CRS reports that discuss these issues in depth and will be updated as needed.
Date: October 18, 2004
Creator: Garcia, Michael John & Wasem, Ruth Ellen
open access

9/11 Commission: Current Legislative Proposals for U.S. Immigration Law and Policy

Description: This report briefly discusses some of the major immigration areas under consideration in comprehensive reform proposals suggested by the 9/11 Commission, including asylum, biometric tracking systems, border security, document security, exclusion, immigration enforcement, and visa issuances. It refers to other CRS reports that discuss these issues in depth and will be updated as needed.
Date: December 6, 2004
Creator: Garcia, Michael John & Wasem, Ruth Ellen
captions transcript

9-11 Commission Final Report Press Conference

Description: Recording of a press conference held by the National Commission on Terrorist Attacks upon the United States to announce the release of the final report and discuss the findings of the commission.
Date: July 22, 2004
Duration: 1 hour 35 minutes 15 seconds
Creator: National Commission on Terrorist Attacks upon the United States
captions transcript

9-11 Commission Hearing #1, April 1, 2003, Part 2

Description: Recording of the first public hearing held by the National Commission on Terrorist Attacks upon the United States on April 1, 2003 at the Alexander Hamilton U.S. Custom House in New York City. This hearing specifically addresses the topics of borders, money, and transportation; law enforcement, domestic intelligence, and homeland security; and immediate response to the attacks. This section includes testimony from Steven Brill on the subject of law enforcement, domestic intelligence, and homeland security.
Date: April 1, 2004
Duration: 42 minutes 26 seconds
Creator: National Commission on Terrorist Attacks upon the United States
captions transcript

9-11 Commission Hearing #7, January 26, 2004, Part 1

Description: Recording of the seventh public hearing held by the National Commission on Terrorist Attacks upon the United States on January 26-27 at the Hart Senate Office Building in Washington, D.C. This hearing specifically addresses the topics of border and aviation security. In addition, several staff statements from the Commission were delivered during the course of the proceedings. This section includes the first staff statement on the entry of the 9/11 hijackers into the United States and the first panel on the border security system prior to September 11, with testimony from Mary A. Ryan and Doris Meissner.
Date: January 26, 2004
Duration: 2 hours 36 minutes 19 seconds
Creator: National Commission on Terrorist Attacks upon the United States
captions transcript

9-11 Commission Hearing #7, January 26, 2004, Part 2

Description: Recording of the seventh public hearing held by the National Commission on Terrorist Attacks upon the United States on January 26-27 at the Hart Senate Office Building in Washington, D.C. This hearing specifically addresses the topics of border and aviation security. In addition, several staff statements from the Commission were delivered during the course of the proceedings. This section includes the panel on an incident in Florida with testimony from Jose E. Mendelez-Perez.
Date: January 26, 2004
Duration: 49 minutes 16 seconds
Creator: National Commission on Terrorist Attacks upon the United States
captions transcript

9-11 Commission Hearing #7, January 26, 2004, Part 3

Description: Recording of the seventh public hearing held by the National Commission on Terrorist Attacks upon the United States on January 26-27 at the Hart Senate Office Building in Washington, D.C. This hearing specifically addresses the topics of border and aviation security. In addition, several staff statements from the Commission were delivered during the course of the proceedings. This section includes the staff statement on three 9/11 hijackers: identification, watchlisting, and tracking, in addition to the third panel on visas and watchlisting today, with testimony from Maura Harty, Russell E. Travers, and Donna A. Buccella.
Date: January 26, 2004
Duration: 2 hours 18 minutes 48 seconds
Creator: National Commission on Terrorist Attacks upon the United States
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