Hydrogen Storage in Metal-Organic Frameworks (open access)

Hydrogen Storage in Metal-Organic Frameworks

Conventional storage of large amounts of hydrogen in its molecular form is difficult and expensive because it requires employing either extremely high pressure gas or very low temperature liquid. Because of the importance of hydrogen as a fuel, the DOE has set system targets for hydrogen storage of gravimetric (5.5 wt%) and volumetric (40 g L-1) densities to be achieved by 2015. Given that these are system goals, a practical material will need to have higher capacity when the weight of the tank and associated cooling or regeneration system is considered. The size and weight of these components will vary substantially depending on whether the material operates by a chemisorption or physisorption mechanism. In the latter case, metal-organic frameworks (MOFs) have recently been identified as promising adsorbents for hydrogen storage, although little data is available for their sorption behavior. This grant was focused on the study of MOFs with these specific objectives. (1) To examine the effects of functionalization, catenation, and variation of the metal oxide and organic linkers on the low-pressure hydrogen adsorption properties of MOFs. (2) To develop a strategy for producing MOFs with high surface area and porosity to reduce the dead space and increase the hydrogen …
Date: April 26, 2012
Creator: Yaghi, Omar M.
Object Type: Report
System: The UNT Digital Library
Event-by-event study of photon observables in spontaneous and thermal fission (open access)

Event-by-event study of photon observables in spontaneous and thermal fission

None
Date: September 26, 2012
Creator: Vogt, R & Randrup, J
Object Type: Article
System: The UNT Digital Library
Performance Characteristics of Hardware Transactional Memory for Molecular Dynamics Application on BlueGene/Q: Toward Efficient Multithreading Strategies for Large-Scale Scientific Applications (open access)

Performance Characteristics of Hardware Transactional Memory for Molecular Dynamics Application on BlueGene/Q: Toward Efficient Multithreading Strategies for Large-Scale Scientific Applications

None
Date: September 26, 2012
Creator: Kunaseth, M.; Kalia, R. K.; Nakano, A.; Vashishta, P.; Richards, D. F. & Glosli, J. N.
Object Type: Article
System: The UNT Digital Library
Washoe Wisk'e'em Project (open access)

Washoe Wisk'e'em Project

The Washoe Tribe Wiskem Project (Project) was a Congressionally Directed Project identified for funding in the Energy and Water Development and Related Agencies Appropriations Act, 2010. The Project focused on installing up to four small vertical wind turbines at designated locations on Tribal lands to offset energy costs for the Tribe. The Washoe Tribe will use and analyze data collected from the wind turbines to better understand the wind resource.
Date: March 26, 2012
Creator: Hess-McGeown, Tara
Object Type: Report
System: The UNT Digital Library
Position Stability Monitoring of THEthe LCLS Undulator Quadrupoles (open access)

Position Stability Monitoring of THEthe LCLS Undulator Quadrupoles

X-ray FELs demand that the positions of undulator components be stable to less than 1 {mu}m per day. Simultaneously, the undulator length increases significantly in order to saturate at x-ray wavelengths. To minimize the impact of the outside environment, the Linac Coherent Light Source (LCLS) undulator is placed underground, but reliable data about ground motion inside such a tunnel was not available in the required stability range during the planning phase. Therefore, a new position monitor system had been developed and installed with the LCLS undulator. This system is capable of measuring x, y, roll, pitch and yaw of each of the 33 undulator quadrupoles with respect to stretched wires. Instrument resolution is about 10 nm and instrument drift is negligible. Position data of individual quadrupoles can be correlated along the entire 132-m long undulator. The system has been under continuous operation since 2009. This report describes long term experiences with the running system and the observed positional stability of the undulator quadrupoles.
Date: March 26, 2012
Creator: Nuhn, Heinz Dieter; Gassner, Georg & Peters, Franz
Object Type: Article
System: The UNT Digital Library
Metallic Membrane Materials Development for Hydrogen Production from Coal Derived Syngas (open access)

Metallic Membrane Materials Development for Hydrogen Production from Coal Derived Syngas

The goals of Office of Clean Coal are: (1) Improved energy security; (2) Reduced green house gas emissions; (3) High tech job creation; and (4) Reduced energy costs. The goals of the Hydrogen from Coal Program are: (1) Prove the feasibility of a 40% efficient, near zero emissions IGCC plant that uses membrane separation technology and other advanced technologies to reduce the cost of electricity by at least 35%; and (2) Develop H{sub 2} production and processing technologies that will contribute {approx}3% in improved efficiency and 12% reduction in cost of electricity.
Date: February 26, 2012
Creator: Dogan, O. N.; Howard, B. H. & Alman, D. E.
Object Type: Article
System: The UNT Digital Library
Gamma discrimination in pillar structured thermal neutron detectors (open access)

Gamma discrimination in pillar structured thermal neutron detectors

Solid-state thermal neutron detectors are desired to replace {sup 3}He tube based technology for the detection of special nuclear materials. {sup 3}He tubes have some issues with stability, sensitivity to microphonics and very recently, a shortage of {sup 3}He. There are numerous solid-state approaches being investigated that utilize various architectures and material combinations. By using the combination of high-aspect-ratio silicon PIN pillars, which are 2 {micro}m wide with a 2 {micro}m separation, arranged in a square matrix, and surrounded by {sup 10}B, the neutron converter material, a high efficiency thermal neutron detector is possible. Besides intrinsic neutron detection efficiency, neutron to gamma discrimination is an important figure of merit for unambiguous signal identification. In this work, theoretical calculations and experimental measurements are conducted to determine the effect of structure design of pillar structured thermal neutron detectors including: intrinsic layer thickness, pillar height, substrate doping and incident gamma energy on neutron to gamma discrimination.
Date: March 26, 2012
Creator: Shao, Q.; Radev, R. P.; Conway, A. M.; Voss, L. F.; Wang, T. F.; Nikolic, R. J. et al.
Object Type: Article
System: The UNT Digital Library
General Relativistic Magnetohydrodynamic Simulations of Magnetically Choked Accretion Flows around Black Holes (open access)

General Relativistic Magnetohydrodynamic Simulations of Magnetically Choked Accretion Flows around Black Holes

Black hole (BH) accretion flows and jets are qualitatively affected by the presence of ordered magnetic fields. We study fully three-dimensional global general relativistic magnetohydrodynamic (MHD) simulations of radially extended and thick (height H to cylindrical radius R ratio of |H/R| {approx} 0.2-1) accretion flows around BHs with various dimensionless spins (a/M, with BH mass M) and with initially toroidally-dominated ({phi}-directed) and poloidally-dominated (R-z directed) magnetic fields. Firstly, for toroidal field models and BHs with high enough |a/M|, coherent large-scale (i.e. >> H) dipolar poloidal magnetic flux patches emerge, thread the BH, and generate transient relativistic jets. Secondly, for poloidal field models, poloidal magnetic flux readily accretes through the disk from large radii and builds-up to a natural saturation point near the BH. While models with |H/R| {approx} 1 and |a/M| {le} 0.5 do not launch jets due to quenching by mass infall, for sufficiently high |a/M| or low |H/R| the polar magnetic field compresses the inflow into a geometrically thin highly non-axisymmetric 'magnetically choked accretion flow' (MCAF) within which the standard linear magneto-rotational instability is suppressed. The condition of a highly-magnetized state over most of the horizon is optimal for the Blandford-Znajek mechanism that generates persistent relativistic jets with …
Date: April 26, 2012
Creator: McKinney, Jonathan C.; Tchekhovskoy, Alexander & Blandford, Roger D.
Object Type: Article
System: The UNT Digital Library
Measurement of the Cosmic Ray Energy Spectrum Using Hybrid Events of the Pierre Auger Observatory (open access)

Measurement of the Cosmic Ray Energy Spectrum Using Hybrid Events of the Pierre Auger Observatory

None
Date: June 26, 2012
Creator: Settimo, Mariangela & U., /Siegen u. /Salento
Object Type: Article
System: The UNT Digital Library
Reduced order modelling for dynamic simulations: LDRD feasibility study final report (open access)

Reduced order modelling for dynamic simulations: LDRD feasibility study final report

None
Date: November 26, 2012
Creator: Chand, K. K.; Henshaw, W. D. & Vassilevska, T. K.
Object Type: Report
System: The UNT Digital Library
Surfaces of Intermetallics: Quasicrystals and Beyond (open access)

Surfaces of Intermetallics: Quasicrystals and Beyond

The goal of this work is to characterize surfaces of intermetallics, including quasicrystals. In this work, surface characterization is primarily focused on composition and structure using X-ray photoelectron spectroscopy (XPS) and scanning tunneling microscopy (STM) performed under ultrahigh vacuum (UHV) conditions.
Date: October 26, 2012
Creator: Yuen, Chad
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Terahertz Radiation from a Pipe with Small Corrugations (open access)

Terahertz Radiation from a Pipe with Small Corrugations

We have studied through analytical and numerical methods the use of a relativistic electron bunch to drive a metallic beam pipe with small corrugations for the purpose of generating terahertz radiation. For the case of a pipe with dimensions that do not change along its length, we have shown that - with reasonable parameters - one can generate a narrow-band radiation pulse with frequency {approx}1 THz, and total energy of a few milli-Joules. The pulse length tends to be on the order of tens of picoseconds. We have also shown that, if the pipe radius is tapered along its length, the generated pulse will end up with a frequency chirp; if the pulse is then made to pass through a compressor, its final length can be reduced to a few picoseconds and its peak power increased to 1 GW. We have also shown that wall losses tend to be significant and need to be included in the structure design.
Date: January 26, 2012
Creator: Bane, K. L. F. & Stupakov, G.
Object Type: Report
System: The UNT Digital Library
Wynkoop Building Performance Measurement: Water (open access)

Wynkoop Building Performance Measurement: Water

This report is a summary of the water analysis performance for the Denver, Colorado Wynkoop Building. The Wynkoop Building (Figure 1) was built in 2006 as the Environmental Protection Agency (EPA) Region 8 Headquarters intended to house over 900 occupants in the 301,292 gross square feet (248,849 rentable square feet). The building was built on a brownfield in the Lower Downtown Historic District as part of an urban redevelopment effort. The building was designed and constructed through a public-private partnership with the sustainable design elements developed jointly by General Services Administration (GSA) and EPA. That partnership is still active with all parties still engaged to optimize building operations and use the building as a Learning Laboratory. The building design achieved U.S. Green Building Council Leadership in Energy and Environmental Design for New Construction (LEED-NC) Gold Certification in 2008 (Figure 2) and a 2008 EPA Energy Star Rating of 96 with design highlights that include: (1) Water use was designed to use 40% less than a typical design baseline. The design included low flow fixtures, waterless urinals and dual flush toilets; (2) Native and adaptive vegetation were selected to minimize the need for irrigation water for landscaping; and (3) Energy use …
Date: August 26, 2012
Creator: Fowler, Kimberly M. & Kora, Angela R.
Object Type: Report
System: The UNT Digital Library
HANFORD RIVER PROTECTION PROJECT ENHANCED MISSION PLANNING THROUGH INNOVATIVE TOOLS LIFECYCLE COST MODELING AND AQUEOUS THERMODYNAMIC MODELING - 12134 (open access)

HANFORD RIVER PROTECTION PROJECT ENHANCED MISSION PLANNING THROUGH INNOVATIVE TOOLS LIFECYCLE COST MODELING AND AQUEOUS THERMODYNAMIC MODELING - 12134

Two notable modeling efforts within the Hanford Tank Waste Operations Simulator (HTWOS) are currently underway to (1) increase the robustness of the underlying chemistry approximations through the development and implementation of an aqueous thermodynamic model, and (2) add enhanced planning capabilities to the HTWOS model through development and incorporation of the lifecycle cost model (LCM). Since even seemingly small changes in apparent waste composition or treatment parameters can result in large changes in quantities of high-level waste (HLW) and low-activity waste (LAW) glass, mission duration or lifecycle cost, a solubility model that more accurately depicts the phases and concentrations of constituents in tank waste is required. The LCM enables evaluation of the interactions of proposed changes on lifecycle mission costs, which is critical for decision makers.
Date: January 26, 2012
Creator: KL, PIERSON & FL, MEINERT
Object Type: Article
System: The UNT Digital Library
SAMPLE RESULTS FROM THE INTEGRATED SALT DISPOSITION PROGRAM MACROBATCH 5 TANK 21H QUALIFICATION SAMPLES (open access)

SAMPLE RESULTS FROM THE INTEGRATED SALT DISPOSITION PROGRAM MACROBATCH 5 TANK 21H QUALIFICATION SAMPLES

Savannah River National Laboratory (SRNL) analyzed samples from Tank 21H in support of qualification of Macrobatch (Salt Batch) 5 for the Integrated Salt Disposition Project (ISDP). This document reports partial results of the analyses of samples of Tank 21H. No issues with the projected Salt Batch 5 strategy are identified. Results of the analyses of the Tank 21H samples from this report in conjunction with the findings of the previous report, indicates that the material does not display any unusual characteristics.
Date: March 26, 2012
Creator: Peters, T. & Fink, S.
Object Type: Report
System: The UNT Digital Library
SAFETY AND SENSITIVITY OF NITROGLYCERINE (NG) MIXTURES (open access)

SAFETY AND SENSITIVITY OF NITROGLYCERINE (NG) MIXTURES

None
Date: October 26, 2012
Creator: Hsu, P C; Hust, G & Schmidt, R
Object Type: Report
System: The UNT Digital Library
Microstructure and Corrosion Behavior of the Cu-Pd-X Ternary Alloys for Hydrogen Separation Membranes (open access)

Microstructure and Corrosion Behavior of the Cu-Pd-X Ternary Alloys for Hydrogen Separation Membranes

CuPd alloys are among the most promising candidate materials for hydrogen separation membranes and membrane reactor applications due to their high hydrogen permeability and better sulfur resistance. In order to reduce the Pd content and, therefore, the cost of the membrane materials, efforts have been initiated to develop CuPdM ternary alloys having a bcc structure. The advantages of having Pd as a hydrogen separation membrane are: (1) high hydrogen selectivity; and (2) high hydrogen permeability. The disadvantages are: (1) high cost; (2) hydrogen embrittlement ({alpha} {yields} {beta} Pd hydride); and (3) sulfur poisoning. Experiments (XRD, SEM/EDS) verified that Mg, Al, La, Y and Ti are promising alloying elements to expand the B2 phase region in Cu-Pd binary system. HT-XRD showed that the B2 to FCC transition temperatures for Cu-Pd-X (X = Mg, Al, La, Y and Ti) are higher than that of Cu-Pd binary alloys. While the Cu-50Pd alloy had the highest corrosion resistance to the H2S containing syngas, the Cu-Pd-Mg alloy had a comparable resistance.
Date: February 26, 2012
Creator: Dogan, O. N.; Gao, M. C. & Howard, B. H.
Object Type: Article
System: The UNT Digital Library
FULL SCALE TESTING TECHNOLOGY MATURATION OF A THIN FILM EVAPORATOR FOR HIGH-LEVEL LIQUID WASTE MANAGEMENT AT HANFORD - 12125 (open access)

FULL SCALE TESTING TECHNOLOGY MATURATION OF A THIN FILM EVAPORATOR FOR HIGH-LEVEL LIQUID WASTE MANAGEMENT AT HANFORD - 12125

Simulant testing of a full-scale thin-film evaporator system was conducted in 2011 for technology development at the Hanford tank farms. Test results met objectives of water removal rate, effluent quality, and operational evaluation. Dilute tank waste simulant, representing a typical double-shell tank supernatant liquid layer, was concentrated from a 1.1 specific gravity to approximately 1.5 using a 4.6 m{sup 2} (50 ft{sup 2}) heated transfer area Rototherm{reg_sign} evaporator from Artisan Industries. The condensed evaporator vapor stream was collected and sampled validating efficient separation of the water. An overall decontamination factor of 1.2E+06 was achieved demonstrating excellent retention of key radioactive species within the concentrated liquid stream. The evaporator system was supported by a modular steam supply, chiller, and control computer systems which would be typically implemented at the tank farms. Operation of these support systems demonstrated successful integration while identifying areas for efficiency improvement. Overall testing effort increased the maturation of this technology to support final deployment design and continued project implementation.
Date: January 26, 2012
Creator: AR, TEDESCHI; JE, CORBETT; RA, WILSON & J, LARKIN
Object Type: Article
System: The UNT Digital Library
PROPERTIES IMPORTANT TO MIXING FOR WTP LARGE SCALE INTEGRATED TESTING (open access)

PROPERTIES IMPORTANT TO MIXING FOR WTP LARGE SCALE INTEGRATED TESTING

Large Scale Integrated Testing (LSIT) is being planned by Bechtel National, Inc. to address uncertainties in the full scale mixing performance of the Hanford Waste Treatment and Immobilization Plant (WTP). Testing will use simulated waste rather than actual Hanford waste. Therefore, the use of suitable simulants is critical to achieving the goals of the test program. External review boards have raised questions regarding the overall representativeness of simulants used in previous mixing tests. Accordingly, WTP requested the Savannah River National Laboratory (SRNL) to assist with development of simulants for use in LSIT. Among the first tasks assigned to SRNL was to develop a list of waste properties that matter to pulse-jet mixer (PJM) mixing of WTP tanks. This report satisfies Commitment 5.2.3.1 of the Department of Energy Implementation Plan for Defense Nuclear Facilities Safety Board Recommendation 2010-2: physical properties important to mixing and scaling. In support of waste simulant development, the following two objectives are the focus of this report: (1) Assess physical and chemical properties important to the testing and development of mixing scaling relationships; (2) Identify the governing properties and associated ranges for LSIT to achieve the Newtonian and non-Newtonian test objectives. This includes the properties to support …
Date: April 26, 2012
Creator: Koopman, D.; Martino, C. & Poirier, M.
Object Type: Report
System: The UNT Digital Library
Forward Drell-Yan plus backward jet as a test of BFKL evolution (open access)

Forward Drell-Yan plus backward jet as a test of BFKL evolution

N/A
Date: March 26, 2012
Creator: M., Hentschinski & Salas, C.
Object Type: Article
System: The UNT Digital Library
DOE Project: Optimization of Advanced Diesel Engine Combustion Strategies "University Research in Advanced Combustion and Emissions Control" Office of FreedomCAR and Vehicle Technologies Program (open access)

DOE Project: Optimization of Advanced Diesel Engine Combustion Strategies "University Research in Advanced Combustion and Emissions Control" Office of FreedomCAR and Vehicle Technologies Program

The goal of the present technology development was to increase the efficiency of internal combustion engines while minimizing the energy penalty of meeting emissions regulations. This objective was achieved through experimentation and the development of advanced combustion regimes and emission control strategies, coupled with advanced petroleum and non-petroleum fuel formulations. To meet the goals of the project, it was necessary to improve the efficiency of expansion work extraction, and this required optimized combustion phasing and minimized in-cylinder heat transfer losses. To minimize fuel used for diesel particulate filter (DPF) regeneration, soot emissions were also minimized. Because of the complex nature of optimizing production engines for real-world variations in fuels, temperatures and pressures, the project applied high-fidelity computing and high-resolution engine experiments synergistically to create and apply advanced tools (i.e., fast, accurate predictive models) developed for low-emission, fuel-efficient engine designs. The companion experiments were conducted using representative single- and multi-cylinder automotive and truck diesel engines.
Date: October 26, 2012
Creator: Reitz, Rolf; Foster, D.; Ghandhi, J.; Rothamer, D.; Rutland, C.; Sanders, S. et al.
Object Type: Report
System: The UNT Digital Library
Nevada National Security Site Radiological Control Manual (open access)

Nevada National Security Site Radiological Control Manual

This document supersedes DOE/NV/25946--801, 'Nevada Test Site Radiological Control Manual,' Revision 1 issued in February 2010. Brief Description of Revision: A complete revision to reflect a recent change in name for the NTS; changes in name for some tenant organizations; and to update references to current DOE policies, orders, and guidance documents. Article 237.2 was deleted. Appendix 3B was updated. Article 411.2 was modified. Article 422 was re-written to reflect the wording of DOE O 458.1. Article 431.6.d was modified. The glossary was updated. This manual contains the radiological control requirements to be used for all radiological activities conducted by programs under the purview of the U.S. Department of Energy (DOE) and the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO). Compliance with these requirements will ensure compliance with Title 10 Code of Federal Regulations (CFR) Part 835, 'Occupational Radiation Protection.' Programs covered by this manual are located at the Nevada National Security Site (NNSS); Nellis Air Force Base and North Las Vegas, Nevada; Santa Barbara and Livermore, California; and Andrews Air Force Base, Maryland. In addition, fieldwork by NNSA/NSO at other locations is covered by this manual. Current activities at NNSS include operating low-level radioactive …
Date: March 26, 2012
Creator: Council, Radiological Control Managers’
Object Type: Report
System: The UNT Digital Library
THERMAL UPGRADING OF 9977 RADIOACTIVE MATERIAL (RAM) TYPE B PACKAGE (open access)

THERMAL UPGRADING OF 9977 RADIOACTIVE MATERIAL (RAM) TYPE B PACKAGE

The 9977 package is a radioactive material package that was originally certified to ship Heat Sources and RTG contents up to 19 watts and it is now being reviewed to significantly expand its contents in support of additional DOE missions. Thermal upgrading will be accomplished by employing stacked 3013 containers, a 3013 aluminum spacer and an external aluminum sleeve for enhanced heat transfer. The 7th Addendum to the original 9977 package Safety Basis Report describing these modifications is under review for the DOE certification. The analyses described in this paper show that this well-designed and conservatively analyzed package can be upgraded to carry contents with decay heat up to 38 watts with some simple design modifications. The Model 9977 package has been designed as a replacement for the Department of Transportation (DOT) Fissile Specification 6M package. The 9977 package is a very versatile Type B package which is certified to transport and store a wide spectrum of radioactive materials. The package was analyzed quite conservatively to increase its usefulness and store different payload configurations. Its versatility is evident from several daughter packages such as the 9978 and H1700, and several addendums where the payloads have been modified to suit the …
Date: March 26, 2012
Creator: Gupta, N. & Abramczyk, G.
Object Type: Article
System: The UNT Digital Library
Ultra-relativistic Heavy-ion Physics with AFTER@LHC (open access)

Ultra-relativistic Heavy-ion Physics with AFTER@LHC

None
Date: November 26, 2012
Creator: Rakotozafindrabe, A.; Arnaldi, R.; Brodsky, S.J.; Chambert, V.; Didelez, J.P.; Genolini, B. et al.
Object Type: Article
System: The UNT Digital Library