Certification Testing and Demonstration of Insulated Pressure Vessels for Vehicular Hydrogen Storage (open access)

Certification Testing and Demonstration of Insulated Pressure Vessels for Vehicular Hydrogen Storage

Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen or ambient-temperature compressed hydrogen. This flexibility results in multiple advantages with respect to compressed hydrogen tanks or low-pressure liquid hydrogen tanks. Our work is directed at verifying that commercially available aluminum-lined, fiber-wrapped pressure vessels can be safely used to store liquid hydrogen. A series of tests have been conducted, and the results indicate that no significant vessel damage has resulted from cryogenic operation. Future activities include a demonstration project in which the insulated pressure vessels will be installed and tested on two vehicles. A draft standard will also be generated for certification of insulated pressure vessels.
Date: May 22, 2002
Creator: Aceves, S. M.; Martinez-Frias, J. & Espinosa-Loza, F.
Object Type: Article
System: The UNT Digital Library
Certification Testing and Demonstration of Insulated Pressure Vessels for Vehicular Hydrogen and Natural Gas Storage (open access)

Certification Testing and Demonstration of Insulated Pressure Vessels for Vehicular Hydrogen and Natural Gas Storage

We are working on developing an alternative technology for storage of hydrogen or natural gas on light-duty vehicles. This technology has been titled insulated pressure vessels. Insulated pressure vessels are cryogenic-capable pressure vessels that can accept either liquid fuel or ambient-temperature compressed fuel. Insulated pressure vessels offer the advantages of cryogenic liquid fuel tanks (low weight and volume), with reduced disadvantages (fuel flexibility, lower energy requirement for fuel liquefaction and reduced evaporative losses). The work described in this paper is directed at verifying that commercially available pressure vessels can be safely used to store liquid hydrogen or LNG. The use of commercially available pressure vessels significantly reduces the cost and complexity of the insulated pressure vessel development effort. This paper describes a series of tests that have been done with aluminum-lined, fiber-wrapped vessels to evaluate the damage caused by low temperature operation. All analysis and experiments to date indicate that no significant damage has resulted. Future activities include a demonstration project in which the insulated pressure vessels will be installed and tested on two vehicles. A draft standard will also be generated for obtaining insulated pressure vessel certification.
Date: May 22, 2002
Creator: Aceves, S. M.; Martinez-Frias, J.; Espinosa-Loza, F.; Schaffer, R. & Clapper, W.
Object Type: Article
System: The UNT Digital Library
Supporting collaborative computing and interaction (open access)

Supporting collaborative computing and interaction

To enable collaboration on the daily tasks involved in scientific research, collaborative frameworks should provide lightweight and ubiquitous components that support a wide variety of interaction modes. We envision a collaborative environment as one that provides a persistent space within which participants can locate each other, exchange synchronous and asynchronous messages, share documents and applications, share workflow, and hold videoconferences. We are developing the Pervasive Collaborative Computing Environment (PCCE) as such an environment. The PCCE will provide integrated tools to support shared computing and task control and monitoring. This paper describes the PCCE and the rationale for its design.
Date: May 22, 2002
Creator: Agarwal, Deborah; McParland, Charles & Perry, Marcia
Object Type: Article
System: The UNT Digital Library
Development, field testing of a laser instrument for the measurement of sediment reference concentration in the MARGINS Program. Final report (open access)

Development, field testing of a laser instrument for the measurement of sediment reference concentration in the MARGINS Program. Final report

A small grant was added to an ongoing Navy program to extend the scope of ongoing work by development of a new laser instrument. The instrument, MSCAT (Miniature Scattering and Transmissometry) uses small angle scattering to obtain the needed multi-parameter information for measurement of particle size distribution and number density. During the short course of the grant, the instrument was built and tested in a field experiment off the coast of North Carolina. Useful data were obtained, and these have been presented at the Fall Meeting of the American Geophysical Union in 1994.
Date: May 22, 1998
Creator: Agrawal, Yogesh C.
Object Type: Report
System: The UNT Digital Library
Initial experiments of RF gas plasma source for heavy ionfusion (open access)

Initial experiments of RF gas plasma source for heavy ionfusion

The Source Injector Program for the US Heavy Ion Fusion Virtual National Laboratory is currently exploring the feasibility of using RF gas plasma sources for a HIF driver. This source technology is presently the leading candidate for the multiple aperture concept, in which bright millimeter size beamlets are extracted and accelerated electrostatically up to 1 MeV before the beamlets are allowed to merge and form 1 A beams. Initial experiments have successfully demonstrated simultaneously high current density, {approx} 100 mA/cm{sup 2} and fast turn on, {approx} 1 {micro}s. These experiments were also used to explore operating ranges for pressure and RF power. Results from these experiments are presented as well as progress and plans for the next set of experiments for these sources.
Date: May 22, 2002
Creator: Ahle, L.; Hall, R.; Molvik, A. W.; Chacon-Golcher, E.; Kwan, J. W.; Leung, K. N. et al.
Object Type: Article
System: The UNT Digital Library
Photoconductive properties of GaAs{sub 1{minus}x}N{sub x} double heterostructures as a function of excitation wavelength (open access)

Photoconductive properties of GaAs{sub 1{minus}x}N{sub x} double heterostructures as a function of excitation wavelength

The ternary semiconductor GaAs{sub 1{minus}x}N{sub x} with 0 < x < 0.3 can be grown epitaxially on GaAs and has a very large bowing coefficient. The alloy bandgap can be reduced to about 1.0 eV with about a 3% nitrogen addition. In this work, the authors measured the internal spectral response and recombination lifetime of a number of alloys using the ultra-high frequency photoconductive decay (UHFPCD) method. The data shows that the photoconductive excitation spectra of the GaAs{sub 0.97}N{sub 0.03} alloy shows a gradual increase in response through the absorption edge near E{sub g}. This contrasts with most direct bandgap semiconductors that show a steep onset of photoresponse at E{sub g}. The recombination lifetimes frequently are much longer than expected from radiative recombination and often exceeded 1.0{mu}s. The data were analyzed in terms of a band model that includes large potential fluctuations in the conduction band due to the random distribution of nitrogen atoms in the alloy.
Date: May 22, 2000
Creator: Ahrenkiel, R. K.; Mascarenhas, A.; Johnston, S. W.; Zhang, Y.; Friedman, D. J. & Vernon, S. M.
Object Type: Article
System: The UNT Digital Library
Global Cooling: Effect of Urban Albedo on Global Temperature (open access)

Global Cooling: Effect of Urban Albedo on Global Temperature

In many urban areas, pavements and roofs constitute over 60% of urban surfaces (roof 20-25%, pavements about 40%). The roof and the pavement albedo can be increased by about 0.25 and 0.10, respectively, resulting in a net albedo increase for urban areas of about 0.1. Many studies have demonstrated building cooling-energy savings in excess of 20% upon raising roof reflectivity from an existing 10-20% to about 60%. We estimate U.S. potential savings in excess of $1 billion (B) per year in net annual energy bills. Increasing albedo of urban surfaces can reduce the summertime urban temperature and improve the urban air quality. Increasing the urban albedo has the added benefit of reflecting more of the incoming global solar radiation and countering the effect of global warming. We estimate that increasing albedo of urban areas by 0.1 results in an increase of 3 x 10{sup -4} in Earth albedo. Using a simple global model, the change in air temperature in lowest 1.8 km of the atmosphere is estimated at 0.01K. Modelers predict a warming of about 3K in the next 60 years (0.05K/year). Change of 0.1 in urban albedo will result in 0.01K global cooling, a delay of {approx}0.2 years in …
Date: May 22, 2007
Creator: Akbari, Hashem; Menon, Surabi & Rosenfeld, Arthur
Object Type: Article
System: The UNT Digital Library
Quality + safety = productivity: The implosion of Plant 7 (open access)

Quality + safety = productivity: The implosion of Plant 7

At the Fernald Environmental Restoration Management Corporation (FERMCO), our product is a clean site. We measure productivity by our progress in taking down buildings and dispositioning hazardous waste. To those ends, Quality and Safety work together to ensure that productivity is gained in the safest way possible. The Plant 7 deconstruction is an example of how this teamwork has increased productivity at the site.
Date: May 22, 1995
Creator: Alhadeff, N. & Abernathy, L.
Object Type: Article
System: The UNT Digital Library
US DOE and Polish Institute for Ecology of Industrial Areas JCCES FY01 Annual Report (open access)

US DOE and Polish Institute for Ecology of Industrial Areas JCCES FY01 Annual Report

The project Production Scale Implementation of a Petroleum Contaminated Soils Bioreactor was launched in FY00 and showed that bioremediation can be performed under strictly controlled conditions. Initial results showed a 50 percent reduction of total petroleum hydrocarbon concentration in soil from the Czechowice-Dziedzice refinery. It was determined that changes in the design and construction of the bioreactor could improve system performance.
Date: May 22, 2002
Creator: Altman, D. J.
Object Type: Report
System: The UNT Digital Library
Reach the Bottom Line of the Sbottom Search (open access)

Reach the Bottom Line of the Sbottom Search

We propose a new search strategy for directly-produced sbottoms at the LHC with a small mass splitting between the sbottom and its decayed stable neutralino. Our search strategy is based on boosting sbottoms through an energetic initial state radiation jet. In the final state, we require a large missing transverse energy and one or two b-jets besides the initial state radiation jet. We also define a few kinematic variables to further increase the discovery reach. For the case that the sbottom mainly decays into the bottom quark and the stable neutralino, we have found that even for a mass splitting as small as 10 GeV sbottoms with masses up to around 400 GeV can be excluded at the 95% confidence level with 20 inverse femtobarn data at the 8 TeV LHC.
Date: May 22, 2012
Creator: Alvarez, Ezequiel & Bai, Yang
Object Type: Article
System: The UNT Digital Library
Theory of field-reversed mirrors and field-reversed plasma-gun experiments. Paper IAEA-CN-38/R-2 (open access)

Theory of field-reversed mirrors and field-reversed plasma-gun experiments. Paper IAEA-CN-38/R-2

Experimental and theoretical studies of field reversal in a mirror machine are reported. Plasma-gun experiments demonstrate that reversed-field plasma layers are formed. Low energy plasma flowing behind the initially produced plasma front prevents tearing of the layer from the gun muzzle. MHD simulation shows that tearing can be obtained by impeding the slow plasma flow with a plasma divider. It is demonstrated theoretically that a field-reversed mirror imbedded in a multipole field can be sustained in steady state with neutral-beam injection even in the absence of impurities. MHD stability analysis shows that growth rates of elongated reversed-field theta-pinch configurations decrease with axial extension, which indicates the importance of including finite Larmor radius in the analysis. Tilting-mode criteria are dramatically improved by proper shaping, and a problimak shape is proposed. Tearing mode stability of reversed-field theta-pinches is greatly enhanced by flux exclusion. Self-consistent, 1-1/2-dimensional transport codes have been developed, and initial results are presented.
Date: May 22, 1980
Creator: Anderson, D.V.; Auerbach, S.P. & Berk, H.L.
Object Type: Article
System: The UNT Digital Library
Simultaneous Energy Savings and IEQ Improvements in Relocatable Classrooms (open access)

Simultaneous Energy Savings and IEQ Improvements in Relocatable Classrooms

Relocatable classrooms (RCs) are commonly used by school districts with changing demographics and enrollment sizes. We designed and constructed four energy-efficient RCs for this study to demonstrate technologies with the potential to simultaneously improve energy efficiency and indoor environmental quality (IEQ). Two were installed at each of two school districts, and energy use and IEQ parameters were monitored during occupancy. Two RCs (one per school) were finished with materials selected for reduced emissions of toxic and odorous volatile organic compounds (VOCs). Each had two HVAC systems, operated on alternate weeks, consisting of a standard heat-pump system and an indirect-direct evaporative cooling (IDEC) system with gas-fired hydronic heating. The IDEC system provides continuous outside air ventilation at {sup 3}15 CFM (7.5 L s-1) person-1, efficient particle filtration while using significantly less energy for cooling. School year long measurements included: carbon dioxide (CO2), particles, VOCs, temperature, humidity, thermal comfort, noise, meteorology, and energy use. IEQ monitoring results indicate that important ventilation-relevant indoor CO2 and health-relevant VOC concentration reductions were achieved while average cooling and heating energy costs were simultaneously reduced by 50 percent and 30 percent, respectively.
Date: May 22, 2003
Creator: Apte, Michael G.; Dibartolomeo, Dennis; Hotchi, Toshi; Hodgson, Alfred T.; Lee, Seung-Min; Liff, Shawna M. et al.
Object Type: Report
System: The UNT Digital Library
Transversely Polarized L Production. (open access)

Transversely Polarized L Production.

Transversely polarized {Lambda} production in hard scattering processes is discussed in terms of a leading twist T-odd fragmentation function which describes the fragmentation of an unpolarized quark into a transversely polarized {Lambda}. We focus on the properties of this function and its relevance for the RHIC and HERMES experiments.
Date: May 22, 2000
Creator: BORER, D.
Object Type: Article
System: The UNT Digital Library
AGS 20th anniversary celebration (open access)

AGS 20th anniversary celebration

On May 22, 1980, a symposium was held at Brookhaven to celebrate the 20th birthday of the AGS, to recall its beginnings, and to review major discoveries that have been made with its beams. The talks at the symposium are recorded in this volume.
Date: May 22, 1980
Creator: Baggett, N.V. (ed.)
Object Type: Report
System: The UNT Digital Library
Enhanced adhesion for LIGA microfabrication by using a buffer layer (open access)

Enhanced adhesion for LIGA microfabrication by using a buffer layer

The present invention is an improvement on the LIGA microfabrication process wherein a buffer layer is applied to the upper or working surface of a substrate prior to the placement of a resist onto the surface of the substrate. The buffer layer is made from an inert low-Z material (low atomic weight), a material that absorbs secondary X-rays emissions from the substrate that are generated from the substrate upon exposure to a primary X-rays source. Suitable materials for the buffer layer include polyamides and polyimide. The preferred polyimide is synthesized from pyromellitic anhydride and oxydianiline (PMDA-ODA).
Date: May 22, 1998
Creator: Bajikar, Sateesh S.; DeCarlo, Francesco & Song, Joshua J.
Object Type: Patent
System: The UNT Digital Library
EUVL Mask Blank Repair (open access)

EUVL Mask Blank Repair

EUV mask blanks are fabricated by depositing a reflective Mo/Si multilayer film onto super-polished substrates. Small defects in this thin film coating can significantly alter the reflected field and introduce defects in the printed image. Ideally one would want to produce defect-free mask blanks; however, this may be very difficult to achieve in practice. One practical way to increase the yield of mask blanks is to effectively repair multilayer defects, and to this effect they present two complementary defect repair strategies for use on multilayer-coated EUVL mask blanks. A defect is any area on the mask which causes unwanted variations in EUV dose in the aerial image obtained in a printing tool, and defect repair is correspondingly defined as any strategy that renders a defect unprintable during exposure. The term defect mitigation can be adopted to describe any strategy which renders a critical defect non-critical when printed, and in this regard a non-critical defect is one that does not adversely affect device function. Defects in the patterned absorber layer consist of regions where metal, typically chrome, is unintentionally added or removed from the pattern leading to errors in the reflected field. There currently exists a mature technology based on ion …
Date: May 22, 2002
Creator: Barty, A.; Mirkarimi, P.; Stearns, D. G.; Sweeney, D.; Chapman, H. N.; Clift, M. et al.
Object Type: Article
System: The UNT Digital Library
Final Report - Dynamic Path Scheduling through Extensions to Generalized Multiprotocol Label Switching (GMPLS) (open access)

Final Report - Dynamic Path Scheduling through Extensions to Generalized Multiprotocol Label Switching (GMPLS)

The major accomplishments of the project are the successful software implementation of the Phase I scheduling algorithms for GMPLS Label Switched Paths (LSPs) and the extension of the IETF Path Computation Element (PCE) Protocol to support scheduling extensions. In performing this work, we have demonstrated the theoretical work of Phase I, analyzed key issues, and made relevant extensions. Regarding the software implementation, we developed a proof of concept prototype as part of our Algorithm Evaluation System (AES). This implementation uses the Linux operating system to provide software portability and will be the foundation for our commercial software. To demonstrate proof of concept, we have implemented LSP scheduling algorithms to support two of the key GMPLS switching technologies (Lambda and Packet) and support both Fixed Path (FP) and Switched Path (SP) routing. We chose Lambda and Packet because we felt it was essential to include both circuit and packet switching technologies as well as to address all-optical switching in the study. As conceptualized in Phase I, the FP algorithms use a traditional approach where the LSP uses the same physical path for the entire service duration while the innovative SP algorithms allow the physical path to vary during the service duration. …
Date: May 22, 2009
Creator: Battou, Principal Investigator: Dr. Abdella
Object Type: Report
System: The UNT Digital Library
Project C-187-D design requirements for redox production plants (open access)

Project C-187-D design requirements for redox production plants

The following outline of the requirements for the Redox Production Plant design is transmitted to the Kellex Corporation by the General Electric Company to be used in carrying out the assignment directed by Work Authority C-187-C. This outline briefly describes the critical features of design and emphasizes the General Electric desires for certain types of process and engineering design. The purpose of this transmittal is to outline the minimum requirements as to process flow sheet and design criteria to initiate the carrying out of this assignment by Kellex Corporation. This document was originally produced on May 22, 1948 and was declassified on July 28, 1994.
Date: May 22, 1948
Creator: Beaton, R. H.
Object Type: Report
System: The UNT Digital Library
Reference design for the standard mirror hybrid reactor (open access)

Reference design for the standard mirror hybrid reactor

This report describes the results of a two-year study by Lawrence Livermore Laboratory and General Atomic Co. to develop a conceptual design for the standard (minimum-B) mirror hybrid reactor. The reactor parameters have been chosen to minimize the cost of producing nuclear fuel (/sup 239/Pu) for consumption in fission power reactors (light water reactors). The deuterium-tritium plasma produces approximately 400 MW of fusion power with a plasma Q of 0.64. The fast-fission blanket, which is fueled with depleted uranium and lithium, generates sufficient tritium to run the reactor, has a blanket energy multiplication of M = 10.4, and has a net fissile breeding ratio of Pu/n = 1.51. The reactor has a net electrical output of 600 MWe, a fissile production of 2000 kg of plutonium per year (at a capacity factor of 0.74), and a net plant efficiency of 0.18. The plasma-containment field is generated by a Yin-Yang magnet using NbTi superconductor, and the neutral beam system uses positive-ion acceleration with beam direct conversion. The spherical blanket is based on gas-cooled fast reactor technology. The fusion components, blanket, and primary heat-transfer loop components are all contained within a prestressed-concrete reactor vessel, which provides magnet restraint and supports the primary …
Date: May 22, 1978
Creator: Bender, D. J.; Fink, J. H.; Galloway, T. R.; Kastenberg, W. E.; Lee, J. D.; Devoto, R. S. et al.
Object Type: Report
System: The UNT Digital Library
Direct releases to the surface and associated complementary cumulative distribution functions in the 1996 performance assessment for the Waste Isolation Pilot Plant: Cuttings, cavings and spallings (open access)

Direct releases to the surface and associated complementary cumulative distribution functions in the 1996 performance assessment for the Waste Isolation Pilot Plant: Cuttings, cavings and spallings

The following topics related to the treatment of cuttings, cavings and spallings releases to the surface environment in the 1996 performance assessment for the Waste Isolation Pilot Plant (WIPP) are presented: (1) mathematical description of models. (2) uncertainty and sensitivity analysis results arising from subjective (i.e., epistemic) uncertainty for individual releases, (3) construction of complementary cumulative distribution functions (CCDFs) arising from stochastic (i.e., aleatory) uncertainty, and (4) uncertainty and sensitivity analysis results for CCDFs. The presented results indicate that direct releases due to cuttings, cavings and spallings do not constitute a serious threat to the effectiveness of the WIPP as a disposal facility for transuranic waste. Even when the effects of uncertain analysis inputs are taken into account, the CCDFs for cuttings, cavings and spallings releases fall substantially to the left of the boundary line specified in the US Environmental Protection Agency standard for the geologic disposal of radioactive waste (40 CFR 191, 40 CFR 194).
Date: May 22, 2000
Creator: Berglund, J. W.; Garner, J. W.; Helton, Jon Craig; Johnson, J. D.; Smith, L. N. & Anderson, R. P.
Object Type: Article
System: The UNT Digital Library
Relativistic beam plasma instability in strong magnetic field (open access)

Relativistic beam plasma instability in strong magnetic field

None
Date: May 22, 1972
Creator: Berk, H.L.
Object Type: Report
System: The UNT Digital Library
Metal organic frameworks as templates for nanoscale NaAlH4 (open access)

Metal organic frameworks as templates for nanoscale NaAlH4

None
Date: May 22, 2009
Creator: Bhakta, R. K.; Herberg, J. L.; Jacobs, B.; Highley, A.; Behrens, R., Jr.; Ockwig, N. W. et al.
Object Type: Article
System: The UNT Digital Library
Thin film CuIn{sub 1{minus}x}Ga{sub x}Se-based solar cells prepared from solution-based precursors (open access)

Thin film CuIn{sub 1{minus}x}Ga{sub x}Se-based solar cells prepared from solution-based precursors

The authors have fabricated high-efficiency thin-film CuIn{sub 1{minus}x}Ga{sub x}Se{sub 2} (CIGS)-based photovoltaic devices from solution-based electroplated (EP) and auto-plated (AP) precursors. As-deposited precursors are Cu-rich CIGS. Compositions were adjusted to CuIn{sub 1{minus}x}Ga{sub x}Se{sub 2} with additional In and Ga by physical vapor deposition (PVD) to the EP and AP precursor films. Auger analysis and grazing incident X-ray diffraction (GIXRD) were performed on devices prepared from EP and AP precursor films. The authors have also analyzed and compared EP, AP, and an PVD CIGS device by deep-level transient spectroscopy (DLTS).
Date: May 22, 2000
Creator: Bhattacharya, R. N.; Balcioglu, A.; Ramanathan, K. & Batchelor, W. K., Ahrenkiel, R. K.
Object Type: Article
System: The UNT Digital Library
Irradiation Testing Facilities at the Hanford Atomic Products Operation (open access)

Irradiation Testing Facilities at the Hanford Atomic Products Operation

A wide range of irradiation testing facilities and services are present at the Hanford Atomic Products Operation. A number of these facilities are described as a means of illustrating the testing equipment and techniques which are currently in use. (auth)
Date: May 22, 1957
Creator: Blasewitz, A. G.
Object Type: Report
System: The UNT Digital Library