Site-dependent free energy barrier for proton reduction on MoS2 edges (open access)

Site-dependent free energy barrier for proton reduction on MoS2 edges

None
Date: May 30, 2013
Creator: Choi, W; Wood, B C; Schwegler, E & Ogitsu, T
Object Type: Article
System: The UNT Digital Library
Investigation on Flame Characteristics and Burner Operability Issues of Oxy-Fuel Combustion (open access)

Investigation on Flame Characteristics and Burner Operability Issues of Oxy-Fuel Combustion

Oxy-fuel combustion has been used previously in a wide range of industrial applications. Oxy- combustion is carried out by burning a hydrocarbon fuel with oxygen instead of air. Flames burning in this configuration achieve higher flame temperatures which present opportunities for significant efficiency improvements and direct capture of CO{sub 2} from the exhaust stream. In an effort to better understand and characterize the fundamental flame characteristics of oxy-fuel combustion this research presents the experimental measurements of flame stability of various oxyfuel flames. Effects of H{sub 2} concentration, fuel composition, exhaust gas recirculation ratio, firing inputs, and burner diameters on the flame stability of these fuels are discussed. Effects of exhaust gas recirculation i.e. CO{sub 2} and H{sub 2}O (steam) acting as diluents on burner operability are also presented. The roles of firing input on flame stability are then analyzed. For this study it was observed that many oxy-flames did not stabilize without exhaust gas recirculation due to their higher burning velocities. In addition, the stability regime of all compositions was observed to decrease as the burner diameter increased. A flashback model is also presented, using the critical velocity gradient g{sub F}) values for CH{sub 4}-O{sub 2}-CO{sub 2} flames. The scaling …
Date: May 30, 2013
Creator: Choudhuri, Ahsan
Object Type: Report
System: The UNT Digital Library
FBI Director: Appointment and Tenure (open access)

FBI Director: Appointment and Tenure

Report that first reviews the legislative history surrounding the enactment of the 1968 and 1976 amendments to the appointment of the FBI Director, as well as information on the nominees to the FBI Directorship since 1972. The report also provides a legal overview of the extension of a Director's tenure.
Date: May 30, 2013
Creator: Chu, Vivian S. & Hogue, Henry B.
Object Type: Report
System: The UNT Digital Library
Compensation for the eddy current effect in the APS storage ring vacuum chamber (open access)

Compensation for the eddy current effect in the APS storage ring vacuum chamber

The amplitude attenuation and the phase shift of the correction magnet field inside the APS storage ring vacuum chamber due to the eddy current effect were measured. A circuit to compensate for this effect was then inserted between the signal source and the magnet power supply. The amplitude was restored with an error of less than 20% of the source signal amplitude and the phase shift was reduced from 80{degrees} to 12{degrees} at 10 Hz.
Date: May 30, 1990
Creator: Chung, Y.
Object Type: Report
System: The UNT Digital Library
A Note on Differencing the Viscous Dissipation Terms for a Newtonian Fluid (open access)

A Note on Differencing the Viscous Dissipation Terms for a Newtonian Fluid

We compare two finite difference approximations for the viscous dissipation terms in the energy equation. We focus on the strain produced by the every-other-zone (e.g., hour-glass and herringbone) modes in the velocity field. Care must be exercised to produce a viscous dissipation rate consistent with the viscous forces. The examples given are for a rectangular staggered grid, but similar considerations apply to other types of grids. Also, these considerations apply to certain algebraic eddy viscosity models and to the shear creation terms in turbulence transport models.
Date: May 30, 2001
Creator: Cloutman, L
Object Type: Report
System: The UNT Digital Library
Liability of Interactive Computer Service for Violating the Fair Housing Act (open access)

Liability of Interactive Computer Service for Violating the Fair Housing Act

None
Date: May 30, 2007
Creator: Cohen, Henry
Object Type: Report
System: The UNT Digital Library
Hose-Coupling. (open access)

Hose-Coupling.

Patent for a new and useful hose coupling, including instructions and illustrations.
Date: May 30, 1899
Creator: Conley, Andrew Jackson
Object Type: Patent
System: The Portal to Texas History
On the Mechanism of Yielding and Flow in Iron (open access)

On the Mechanism of Yielding and Flow in Iron

The activation energy, activation volume, snd frequency factor were evaluated for yielding (delay time for yielding, upper yield stress, lower yield stress, and Luders band propagation) and flow (friction stress, flow stress, and dislocation mobility) for various irons and steels from data in the literature. It was found that the values of these flow parameters and their stress dependence were the same, within experimental error, for both yielding and flow, and for all the materials considered. This suggests that either the same dislocation mechanism is controlling in every case, or that one or more mechanisms possees approximately the same values for these parameters. The dislocation mechanism for which there was closest agreement between theoretical calculations snd experimental data was overcoming the Peierls stress. On the basis of the available experimental data and the present analysis, it is suggested that the upper and lower yield stresses in iron and steel may represent the sudden generation of a large number of dislocations by the double cross-slip mechanism of Koehler and Orowan, rather than the breaking away from a Cottrell atmosphere. (auth)
Date: May 30, 1961
Creator: Conrad, H.
Object Type: Report
System: The UNT Digital Library
Subnanosecond trigger system for ETA (open access)

Subnanosecond trigger system for ETA

A high-voltage trigger system capable of triggering 30, 250 kV spark gaps; each with less than +- 1 ns jitter has been constructed. In addition to low jitter rates, the trigger system must be capable of delivering the high voltage pulses to the spark gaps either simultaneously or sequentially as determined by other system requirements. The trigger system consists of several stages of pulse amplification culminating in 160 kV pulses having 30 ns risetime. The trigger system is described and test data provided.
Date: May 30, 1980
Creator: Cook, E. G.; Lauer, E. J.; Reginato, L. L.; Rogers, D. & Schmidt, J. A.
Object Type: Article
System: The UNT Digital Library
Steel: Key Issues for Congress (open access)

Steel: Key Issues for Congress

None
Date: May 30, 2002
Creator: Cooney, Stephen
Object Type: Report
System: The UNT Digital Library
SNFP detonation phenomena of hydrogen/oxygen in spent fuel containers (open access)

SNFP detonation phenomena of hydrogen/oxygen in spent fuel containers

Movement of spent nuclear fuels from the Hanford K Basins near the Columbia River to dry interim storage facility on the Hanford plateau will require repackaging the fuel in the basin into multi-canister overpacks (MCOs), drying of the fuel, transporting the contained fuel, hot conditioning, and finally interim storage. Each of these functions will be accomplished while the fuel is contained in the MCOs. Hydrogen and oxygen can be generated within the MCOs by several mechanisms. The principal source of hydrogen and oxygen within the MCOs is residual water from the vacuum drying and hot conditioning operations. This document assesses the detonation phenomena of hydrogen and oxygen in the spent fuel containers. Several process scenarios have been identified that could generate detonation pressures that exceed the nominal 10 atmosphere design limit of the MCOs. Only 42 grams of radiolized water are required to establish this condition.
Date: May 30, 1996
Creator: Cooper, T.D.
Object Type: Report
System: The UNT Digital Library
EU-U.S. Economic Ties: Framework, Scope, and Magnitude (open access)

EU-U.S. Economic Ties: Framework, Scope, and Magnitude

This report provides background information and analysis of the U.S.-EU economic relationship for members of the 112th Congress as they contemplate the costs and benefits of closer U.S. economic ties with the EU. It examines the economic and political framework of the relationship and the scope and magnitude of the ties based on data from various sources. In addition, the report analyzes the implications these factors have for U.S. economic policy toward the EU.
Date: May 30, 2012
Creator: Cooper, William H.
Object Type: Report
System: The UNT Digital Library
Russia's Economic Performance and Policies and Their Implications for the United States (open access)

Russia's Economic Performance and Policies and Their Implications for the United States

This report addresses Russian economic policies and performance raise important policy questions for the United States and the U.S.-Russian relationship.
Date: May 30, 2008
Creator: Cooper, William H.
Object Type: Report
System: The UNT Digital Library
Clean Water: Summary of H.R. 961, As Passed (open access)

Clean Water: Summary of H.R. 961, As Passed

The Clean Water Act, which was last amended in 1987, consists of two major parts: regulatory provisions that impose progressively more stringent requirements on industries and cities to abate pollution and meet the statutory goal of zero discharge of pollutants, and provisions that authorize Federal financial assistance for municipal wastewater treatment construction.
Date: May 30, 1995
Creator: Copeland, Claudia
Object Type: Report
System: The UNT Digital Library
Water Quality Issues in the 112th Congress: Oversight and Implementation (open access)

Water Quality Issues in the 112th Congress: Oversight and Implementation

None
Date: May 30, 2012
Creator: Copeland, Claudia
Object Type: Report
System: The UNT Digital Library
Water Quality Issues in the 112th Congress: Oversight and Implementation (open access)

Water Quality Issues in the 112th Congress: Oversight and Implementation

This report discusses water quality legislation. A number of Clean Water Act issues have been the subject of congressional oversight and legislation, including the environmental and economic impacts of Chesapeake Bay restoration efforts, federal promulgation of water quality standards in Florida, regulation of surface coal mining activities in Appalachia, and other CWA regulatory actions. Congressional interest in several of these issues has been reflected in debate over policy provisions of legislation providing FY2012 appropriations for EPA (P.L. 112-74).
Date: May 30, 2012
Creator: Copeland, Claudia
Object Type: Report
System: The UNT Digital Library
AIDS in Africa (open access)

AIDS in Africa

Sub-Saharan Africa has been far more severely affected by AIDS than any other part of the world. The United Nations reports that 25.3 million adults and children are infected with the HIV virus in the region, which has about 10% of the world's population but more than 70% of the worldwide total of infected people. This report discusses this issue in detail, including the cause of the African AIDS epidemic, the social and economic consequences, response and treatment, and U.S. policy.
Date: May 30, 2002
Creator: Copson, Raymond W.
Object Type: Report
System: The UNT Digital Library
HIV/AIDS International Programs: Appropriations, FY2002-FY2004 (open access)

HIV/AIDS International Programs: Appropriations, FY2002-FY2004

None
Date: May 30, 2003
Creator: Copson, Raymond W.
Object Type: Report
System: The UNT Digital Library
Design review report for modifications to RMCS safety class equipment (open access)

Design review report for modifications to RMCS safety class equipment

This report documents the completion of the formal design review for modifications to the Rotary Mode Core Sampling (RMCS) safety class equipment. These modifications are intended to support core sampling operations in waste tanks requiring flammable gas controls. The objective of this review was to approve the Engineering Change Notices affecting safety class equipment used in the RMCS system. The conclusion reached by the review committee was that these changes are acceptable.
Date: May 30, 1997
Creator: Corbett, J.E.
Object Type: Report
System: The UNT Digital Library
A Recirculating Linac Based Synchrotron Light Source for Ultrafast X-Ray Science (open access)

A Recirculating Linac Based Synchrotron Light Source for Ultrafast X-Ray Science

LBNL is pursuing a multi-divisional initiative that has this year further developed design studies and the scientific program for a facility dedicated to the production of x-ray pulses with ultra-short time duration. Our proposed x-ray facility [1] has the short x-ray pulse length ({approx};60 fs FWHM) necessary to study very fast dynamics, high flux (approximately 1011 photons/sec/0.1 percentBW) to study weakly scattering systems, and tuneability over 1-10 keV photon energy. The photon production section of the machine accomodates seven 2m long undulators and six 2T field dipole magnets. The x-ray pulse repetition rate of 10 kHz is matched to studies of dynamical processes (initiated by ultra-short laser pulses) that typicaly have a long recovery time or are not generally cyclic or reversible and need time to allow relaxation, replacement, or flow of the sample. The technique for producing ultra-short x-ray pulses uses relatively long electron bunches to minimise high-peak-current collective effects, and the ultimate x-ray duration is achieved by a combination of bunch manipulation and optical compression.
Date: May 30, 2002
Creator: Corlett, J.N.; Barry, W.; Byrd, J.M.; DeSantis, S.; Heimann, P.; Lidia, S. et al.
Object Type: Article
System: The UNT Digital Library
Synchronization of x-ray pulses to the pump laser in an ultrafast x-ray facility (open access)

Synchronization of x-ray pulses to the pump laser in an ultrafast x-ray facility

Accurate timing of ultrafast x-ray probe pulses emitted from a synchrotron radiation source with respect to a pump laser exciting processes in the sample under study is critical for the investigation of structural dynamics in the femtosecond regime. We describe a scheme for synchronizing femtosecond x-ray pulses relative to a pump laser. X-ray pulses of <100 fs duration are generated from a proposed source based on a recirculating superconducting linac [1,2,3]. Short x-ray pulses are obtained by a process of electron pulse compression, followed by transverse temporal correlation of the electrons, and ultimately x-ray pulse compression. Timing of the arrival of the x-ray pulse with respect to the pump laser is found to be dominated by the operation of the deflecting cavities which provide the transverse temporal correlation of the electrons. The deflecting cavities are driven from a highly stable RF signal derived from a modelocked laser oscillator which is also the origin of the pump l aser pulses.
Date: May 30, 2002
Creator: Corlett, J.N.; Barry, W.; Byrd, J.M.; Schoenlein, R. & Zholents, A.
Object Type: Article
System: The UNT Digital Library
A 2-Liter, 2000 MPa Air Source for the Radiatively Driven Hypersonic Wind Tunnel (open access)

A 2-Liter, 2000 MPa Air Source for the Radiatively Driven Hypersonic Wind Tunnel

The A2 LITE is a 2 liter, 2000 MPa, 750 K ultra-high pressure (UHP) vessel used to demonstrate UHP technology and to provide an air flow for wind tunnel nozzle development. It is the largest volume UHP vessel in the world. The design is based on a 100:1 pressure intensification using a hydraulic ram as a low pressure driver and a three-layer compound cylinder UHP section. Active control of the 900 mm piston stroke in the 63.5 mm bore permits pressure-time profiles ranging from static to constant pressure during flow through a 1 mm throat diameter nozzle for 1 second.
Date: May 30, 2002
Creator: Costantino, M & Lofftus, D
Object Type: Article
System: The UNT Digital Library
Improved Decontamination: Interfacial Transport, and Chemical Properties of Aqueous Surfactant Cleaners (open access)

Improved Decontamination: Interfacial Transport, and Chemical Properties of Aqueous Surfactant Cleaners

The aqueous cleaning parameter of interest in this series of studies was the pH of the aqueous cleaning solution. A sessile droplet of industrial quench oil was analyzed to determine the effect of varied solution pH its removal from a stainless steel surface.
Date: May 30, 2003
Creator: Counce, Robert M.
Object Type: Report
System: The UNT Digital Library
Monte Carlo Simulations of High-Speed, Time-Gated MCP-based X-ray Detectors: Saturation Effects in DC Pulsed Modes and Detector Dynamic Range (open access)

Monte Carlo Simulations of High-Speed, Time-Gated MCP-based X-ray Detectors: Saturation Effects in DC Pulsed Modes and Detector Dynamic Range

We present here results of continued efforts to understand the performance of microchannel plate (MCP)–based, high-speed, gated, x-ray detectors. This work involves the continued improvement of a Monte Carlo simulation code to describe MCP performance coupled with experimental efforts to better characterize such detectors. Our goal is a quantitative description of MCP saturation behavior in both static and pulsed modes. A new model of charge buildup on the walls of the MCP channels is briefly described. The simulation results agree favorably with experimental data obtained with a short-pulse, high-intensity ultraviolet (UV) laser. These results indicate that a weak saturation can change the exponent of gain with voltage and that a strong saturation lead to a gain plateau. These results also demonstrate that the dynamic range of an MCP in pulsed mode has a value of between 10^2 and 10^3.
Date: May 30, 2008
Creator: Craig Kruschwitz, Ming Wu, Ken Moy, Greg Rochau
Object Type: Article
System: The UNT Digital Library