604 research outputs found
Grenville Foreland Deformation and Sedimentation in Southwest Ohio Indicated by Reprocessed Seismic Reflection Profiles near Middletown, Ohio, USA
The late Mesoproterozoic to early Neoproterozoic Middle Run Formation contains vital information about the crustal evolution of the North American Craton. Four reprocessed seismic reflection lines in the vicinity of the AK Steel facility in Middletown, Ohio, provide new insights into the structural and depositional setting of the Middle Run Formation in this region. A residual statics solution improved the resolution and coherency of reflections in these profiles that underlie the Cambrian Mount Simon Sandstone. Reprocessing revealed gently inclined, west-southwest-dipping reflectors and the occurrence of an angular unconformity between the Middle Run Formation and the overlying Paleozoic strata. The weak and discontinuous seismic reflection character of the Middle Run Formation in these seismic lines overlies a sequence of stronger parallel reflections that are like those observed on the eastward ODNR-1-88 seismic line located near core hole DGS 2627, the stratotype of the Middle Run Formation. This inferred thickness indicates that the basin in which the Middle Run Formation was deposited ranges from at least 670 to 1,128 m (2,200 to 3,700 ft) deep at the AK Steel area and dips gently west-southwest, which is in contrast with the moderate easterly dip observed on the ODNR-1-88 seismic line to the northeast. Correlation of these features across the 10 km (approximately 6 mi) cross-strike gap between the AK Steel lines and the ODNR-1-88 seismic line suggests the presence of a reverse fault with approximately 792 m (2,600 ft) of estimated vertical displacement. A regional cross section—including the WSU 1990 seismic line eastward of the ODNR-1-88 line—exhibits a faulted west-verging asymmetric syncline in near proximity to the Grenville Front. This cross section also shows that deformation of the Middle Run Formation and the underlying layered sequence exhibits a consistent tectonic style of reverse faulting and folding that developed in response to Grenville Front tectonism
Optical properties of TiCx (0.64≤x≤0.90) from 0.1 to 30 eV
The stoichiometry-dependent optical properties of bulk samples of TiCx have been determined for four samples in the range 0.64≤x≤0.90. Reflectance and absorptance data taken in the range 0.1-30 eV have been Kramers-Kronig analyzed to obtain the dielectric function and related functions. Interband absorption begins at 0.1 eV or less. The observed interband transitions are interpreted on the basis of existing energy-band calculations. Comparison of optical structure with joint-density-of-states calculations shows that the rigid-band model cannot be applied strictly to explain the x-dependent structure, especially in the 5-10 eV region. The electron-energy-loss functions exhibit two peaks, one near the free-electron plasmon energy and one near 10 eV, both peaks shifting to higher energy as x increases
Optical properties and electronic structure of β′−NiAl
The optical constants and their temperature derivatives have been determined for β′−NiAl from absorption and thermoreflectance measurements in the energy range of 0.2-4.4 eV. The results are interpreted using the self-consistent energy bands of Moruzzi, Williams, and Gelatt. By comparing a calculated joint density of states with ε2, the imaginary part of the dielectric function, good overall agreement is found between theory and experiment. In contrast to earlier analyses, it is found that the 2.5-eV peak in ε2 is primarily due to direct interband transitions terminating near the Fermi surface. This new interpretation of the 2.5-eV feature is discussed in relation to previously reported concentration effects and the rigid-band model
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The Federal Role in Rail Transit Safety
On June 22, 2009, two transit trains in Washington, DC, collided, resulting in nine deaths and dozens of injuries. It was the worst crash in the history of the Washington Metropolitan Area Transit Authority's rail transit system. This crash has raised questions about the safety of rail transit and the government's role in ensuring that safety. Nationwide, rail transit is considered one of the safest modes of transportation. This report discusses the State Safety Oversight Program, which went into effect in 1997 and mandates that states are responsible for the safety of the rail transit systems within their borders. This report also explores several issues that Federal Transit Administration (FTA) representatives have discussed in regards to improving the Safety Oversight Program
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Amtrak: Budget and Reauthorization
Amtrak was created by Congress in 1970 to provide intercity passenger railroad service. Without a yearly federal grant to cover operating losses, Amtrak would not survive as presently configured. This issue brief discusses reform proposals from both the Administration and Amtrak in the 109th Congress. It addresses the appropriations requested by Amtrak, the reluctance of the Administration to provide aid, and its willingness to let Amtrak enter bankruptcy, resulting in restructuring and reform of inefficient operations
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High Speed Rail (HSR) in the United States
This report provides an overview of high speed rail in the United States. It discusses definitions of high speed rail, looks at high speed rail in selected other countries, and describes congressional initiatives to promote HSR, including provisions in the Passenger Rail Investment and Improvement Act of 2008 (P.L. 110-432) and ARRA. The report then surveys rationales for developing HSR, cost estimates for HSR, and some of the challenges expected in implementing HSR
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112th Congress
This report explains what earmarks are and discusses their use in surface transportation finance. It then discusses how federal transportation funding is distributed with a ban in place and how Members of Congress might influence the distribution
Renormalization-Scale-Invariant PQCD Predictions for R_e+e- and the Bjorken Sum Rule at Next-to-Leading Order
We discuss application of the physical QCD effective charge ,
defined via the heavy-quark potential, in perturbative calculations at
next-to-leading order. When coupled with the Brodsky-Lepage-Mackenzie
prescription for fixing the renormalization scales, the resulting series are
automatically and naturally scale and scheme independent, and represent
unambiguous predictions of perturbative QCD. We consider in detail such
commensurate scale relations for the annihilation ratio
and the Bjorken sum rule. In both cases the improved predictions are in
excellent agreement with experiment.Comment: 13 Latex pages with 5 figures; to be published in Physical Review
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Development of a novel solvent for the simultaneous separation of strontium and cesium from dissolved Spent Nuclear Fuel solutions
The recovery of Cs and Sr from acidic solutions by solvent extraction has been investigated. The goal of this project was to develop an extraction process to remove Cs and Sr from high-level waste in an effort to reduce the heat loading in storage. Solvents for the extraction of Cs and Sr separately have been used on both caustic and acidic spent nuclear fuel waste in the past. The objective of this research was to find a suitable solvent for the extraction of both Cs and Sr simultaneously from acidic nitrate media. The solvents selected for this research possess good stability and extraction behavior when mixed together. The extraction experiments were performed with 4 ,4,(5 )-Di-(tbutyldicyclohexano)- 18-crown-6 {DtBuCH18C6}, Calix[4]arene-bis-(tert-octylbenzocrown-6) {BOBCalixC6} and 1-(2,2,3,3-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol {Cs-7SB modifier} in a branched aliphatic kerosene {Isopar® L}. The BOBCalixC6 and Cs-7SB modifier were developed at Oak Ridge National Laboratory (ORNL) by Bonnesen et al. [1]. The values obtained from the SREX solvent for DSr in 1 M nitric acid ranged from 0.7 to 2.2 at 25oC and 10oC respectively. The values for DCs in 1 M nitric acid with the CSSX solvent ranged from 8.0 to 46.0 at 25oC and 10oC respectively. A new mixed solvent, developed at the Idaho National Engineering and Environmental Laboratory (INEEL) by Riddle et al. [2], showed distributions for Sr ranging from 8.8 to 17.4 in 1 M nitric acid at 25oC and 10oC respectively. The DCs for the mixed solvent ranged from 7.7 to 20.2 in 1 M nitric acid at 25oC to 10oC respectively. The unexpectedly high distributions for Sr at both 25oC and 10oC show a synergy in the mixed solvent. The DCs, although lower than with CSSX solvent, still showed good extraction behavior
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