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Air Pollution: EPA Could Take Additional Steps to Help Maximize the Benefits from the 2007 Diesel Emissions Standards (open access)

Air Pollution: EPA Could Take Additional Steps to Help Maximize the Benefits from the 2007 Diesel Emissions Standards

A letter report issued by the General Accounting Office with an abstract that begins "Diesel engine emissions pose health risks, but one major source--heavy-duty diesel vehicles--is critical for our economy. To reduce risks, the Environmental Protection Agency (EPA) has set stringent emissions standards for diesel engines. In 1998, EPA found that some engine makers were violating standards, so they agreed to build engines that meet 2004 standards early, by October 2002. EPA has set even more stringent standards for 2007. GAO was asked to (1) assess the October 2002 deadline's effects on industry and emissions, and (2) obtain stakeholders' views on the readiness of technology for the 2007 standards and EPA's efforts to ensure this. GAO analyzed information from EPA, 10 large trucking companies, the engine makers subject to the early deadline, and other stakeholders."
Date: March 11, 2004
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
The Albany News (Albany, Tex.), Vol. 128, No. 40, Ed. 1 Thursday, March 11, 2004 (open access)

The Albany News (Albany, Tex.), Vol. 128, No. 40, Ed. 1 Thursday, March 11, 2004

Weekly newspaper from Albany, Texas that includes local, county, and state news along with extensive advertising.
Date: March 11, 2004
Creator: Lucas, Melinda L.
Object Type: Newspaper
System: The Portal to Texas History
Texas Jewish Post (Fort Worth, Tex.), Vol. 58, No. 11, Ed. 1 Thursday, March 11, 2004 (open access)

Texas Jewish Post (Fort Worth, Tex.), Vol. 58, No. 11, Ed. 1 Thursday, March 11, 2004

Weekly Jewish newspaper from Fort Worth, Texas that includes local, state, and national news along with extensive advertising.
Date: March 11, 2004
Creator: Wisch, Rene & Wisch-Ray, Sharon
Object Type: Newspaper
System: The Portal to Texas History
The Odem-Edroy Times (Odem, Tex.), Vol. 58, No. 10, Ed. 1 Thursday, March 11, 2004 (open access)

The Odem-Edroy Times (Odem, Tex.), Vol. 58, No. 10, Ed. 1 Thursday, March 11, 2004

Weekly newspaper from Odem, Texas that includes local, state, and national news along with advertising.
Date: March 11, 2004
Creator: Perez, Jerry
Object Type: Newspaper
System: The Portal to Texas History
Hondo Anvil Herald (Hondo, Tex.), Vol. 118, No. 11, Ed. 1 Thursday, March 11, 2004 (open access)

Hondo Anvil Herald (Hondo, Tex.), Vol. 118, No. 11, Ed. 1 Thursday, March 11, 2004

Weekly newspaper from Hondo, Texas that includes local, state, and national news along with extensive advertising.
Date: March 11, 2004
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Polk County Enterprise (Livingston, Tex.), Vol. 122, No. 21, Ed. 1 Thursday, March 11, 2004 (open access)

Polk County Enterprise (Livingston, Tex.), Vol. 122, No. 21, Ed. 1 Thursday, March 11, 2004

Semi-weekly newspaper from Livingston, Texas that includes local, state and national news along with advertising.
Date: March 11, 2004
Creator: White, Barbara
Object Type: Newspaper
System: The Portal to Texas History
Resonance decay effects on anisotropy parameters (open access)

Resonance decay effects on anisotropy parameters

We present the elliptic flow v{sub 2} of pions produced from resonance decays. The transverse momentum p{sub T} spectra of the parent particles are taken from thermal model fits and their v{sub 2} are fit under the assumption that they follow a number-of-constituent-quark (NCQ) scaling law expected from quark-coalescence models. The v{sub 2} of pions from resonance particle decays is found to be similar to the measured pion v{sub 2}. We also propose the measurement of electron v{sub 2} as a means to extract open-charm v{sub 2} and investigate whether a thermalized system of quasi-free quarks and gluons (a quark-gluon plasma) is created in collisions of Au nuclei at RHIC.
Date: March 11, 2004
Creator: Dong, Xin; Esumi, S.; Sorensen, P.; Xu, Nu & Xu, Z.
Object Type: Article
System: The UNT Digital Library
Compositing, Homogenization, and Characterization of Samples from Hanford Tank 241-AN-107 (open access)

Compositing, Homogenization, and Characterization of Samples from Hanford Tank 241-AN-107

As part of the program to provide pretreatment development and testing services to support the River Protection Project-Waste Treatment Plant (RPP-WTP) mission to treat Hanford tank waste, an approximately 5 L sample of waste from Tank 241-AN-107 was received at the Savannah River Technology Center (SRTC). The waste sample was characterized and mixed with recycle streams to provide feed for pretreatment testing. The characterization data provides a basis for rational development of pretreatment processes, verification of tank composition,and development of physical design parameters for the pretreatment plant.
Date: March 11, 2004
Creator: Martin, K.B.
Object Type: Report
System: The UNT Digital Library
Evaluation of the DWPF Cold Chem Dissolution Method with Tank 7 and Tank 51 Radioactive Sludge (open access)

Evaluation of the DWPF Cold Chem Dissolution Method with Tank 7 and Tank 51 Radioactive Sludge

Dissolution experiments were conducted on radioactive sludge from Tank 7, before transfer of the contents of Tank 7 to Tank 51, and the subsequent sludge in Tank 51 to evaluate the effectiveness of the DWPF Cold Chem Method. The DWPF Cold Chem Method is a room temperature dissolution method (DWPF Cold Chem Method) used in the DWPF on the Slurry Receipt and Adjustment Tank (SRAT) samples in preparation for instrumental analysis. Four types of dissolutions experiments were carried out, the DWPF Cold Chem Method, hot aqua regia, sodium peroxide fusion and hot HF-HNO3. The hot HF-HNO3 digestion is modified version of the DWPF method that incorporates a heating step. The hot aqua regia and sodium peroxide fusion digestions were included as reference digestions. The resulting solutions from all the sludge digestions were analyzed by ICP-ES (Inductively Coupled Plasma Emission Spectroscopy). Visual observations and ICP-ES results were used to evaluate the effectiveness of the DWPF Cold Chem by comparison to the hot aqua regia, sodium peroxide fusion and the hot HF-HNO3 digestions. The data and experimental observations support the following conclusions: The DWPF Cold Chem Method seemed to be effective at dissolving initial species of radioactive sludge, but concurrent precipitation of …
Date: March 11, 2004
Creator: Click, D.R.
Object Type: Report
System: The UNT Digital Library
Hamiltonian Description of Convective-cell Generation (open access)

Hamiltonian Description of Convective-cell Generation

The nonlinear statistical growth rate eq for convective cells driven by drift-wave (DW) interactions is studied with the aid of a covariant Hamiltonian formalism for the gyrofluid nonlinearities. A statistical energy theorem is proven that relates eq to a second functional tensor derivative of the DW energy. This generalizes to a wide class of systems of coupled partial differential equations a previous result for scalar dynamics. Applications to (i) electrostatic ion-temperature-gradient-driven modes at small ion temperature, and (ii) weakly electromagnetic collisional DW's are noted.
Date: March 11, 2004
Creator: Krommes, J. A. & Kolesnikov, R. A.
Object Type: Report
System: The UNT Digital Library
The effect of compression on natural graphite anode performance and matrix conductivity (open access)

The effect of compression on natural graphite anode performance and matrix conductivity

Anodes for lithium-ion cells were constructed from three types of natural graphite, two coated spherical and one flaky. Anode samples were compressed from 0 to 300 kg/cm2 and studied in half-cells to study the relations between anode density, SEI formation and anode cyclability. The C/25 formation of the SEI layer was found to depend on the nature of the graphite and the anode density. Compression of the uncoated graphite lead to an increased conductivity, but only slight improvements in the efficiency of the formation process. Compression of the anodes made from the amorphous-carbon-coated graphites greatly improved both the reversible capacity and first-cycle efficiency. In addition, the fraction of the irreversible charge associated with the surface of the graphite increased with compression, from both an increase in the electrolyte contact as well as compression of the amorphous layer. The cyclability of all of the anodes tended to improve with compression. This suggests that it is the improvement in the conductivity of the anode plays more of a role in the improvement in the cyclability than the formation process.
Date: March 11, 2004
Creator: Striebel, K.A.; Sierra, A.; Shim, J.; Wang, C.-W. & Sastry, A.M.
Object Type: Article
System: The UNT Digital Library
Formation of hollow nanocrystals through the nanoscale kirkendall effect (open access)

Formation of hollow nanocrystals through the nanoscale kirkendall effect

We demonstrate that hollow nanocrystals can be synthesized through a mechanism analogous to the Kirkendall Effect, in which pores form due to the difference in diffusion rates between two components in a diffusion couple. Cobalt nanocrystals are chosen as a primary example to show that their reaction in solution with oxygen, sulfur or selenium leads to the formation of hollow nanocrystals of the resulting oxide and chalcogenides. This process provides a general route to the synthesis of hollow nanostructures of large numbers of compounds. A simple extension of this process yields platinum-cobalt oxide yolk-shell nanostructures which may serve as nanoscale reactors in catalytic applications.
Date: March 11, 2004
Creator: Yin, Yadong; Rioux, Robert M.; Erdonmez, Can K.; Hughes, Steven; Somorjai, Gabor A. & Alivisatos, A. Paul
Object Type: Article
System: The UNT Digital Library
Performance Budgeting: OMB's Performance Rating Tool Presents Opportunities and Challenges For Evaluating Program Performance (open access)

Performance Budgeting: OMB's Performance Rating Tool Presents Opportunities and Challenges For Evaluating Program Performance

Testimony issued by the General Accounting Office with an abstract that begins "The Office of Management and Budget's (OMB) Performance Assessment Rating Tool (PART) is meant to provide a consistent approach to evaluating federal programs during budget formulation. The subcommittee asked GAO to discuss its overall findings and recommendations concerning PART, based on a recent report, Performance Budgeting: Observations on the Use of OMB's Program Assessment Rating Tool for the Fiscal Year 2004 Budget (GAO-04-174)."
Date: March 11, 2004
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Archer County News (Archer City, Tex.), No. 11, Ed. 1 Thursday, March 11, 2004 (open access)

Archer County News (Archer City, Tex.), No. 11, Ed. 1 Thursday, March 11, 2004

Weekly newspaper from Archer City, Texas that includes local, state, and national news along with advertising.
Date: March 11, 2004
Creator: Lewis, Shelley
Object Type: Newspaper
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 82, No. 100, Ed. 1 Thursday, March 11, 2004 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 82, No. 100, Ed. 1 Thursday, March 11, 2004

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: March 11, 2004
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Stamford American (Stamford, Tex.), Vol. 83, No. 49, Ed. 1 Thursday, March 11, 2004 (open access)

Stamford American (Stamford, Tex.), Vol. 83, No. 49, Ed. 1 Thursday, March 11, 2004

Weekly newspaper from Stamford, Texas that includes local, state, and national news along with advertising.
Date: March 11, 2004
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 88, No. 90, Ed. 1 Thursday, March 11, 2004 (open access)

North Texas Daily (Denton, Tex.), Vol. 88, No. 90, Ed. 1 Thursday, March 11, 2004

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: March 11, 2004
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Canadian Record (Canadian, Tex.), Vol. 114, No. 11, Ed. 1 Thursday, March 11, 2004 (open access)

The Canadian Record (Canadian, Tex.), Vol. 114, No. 11, Ed. 1 Thursday, March 11, 2004

Weekly newspaper from Canadian, Texas that includes local, state and national news along with some advertising.
Date: March 11, 2004
Creator: Brown, Laurie Ezzell
Object Type: Newspaper
System: The Portal to Texas History
Rio Grande Herald (Rio Grande City, Tex.), Vol. 91, No. 11, Ed. 1 Thursday, March 11, 2004 (open access)

Rio Grande Herald (Rio Grande City, Tex.), Vol. 91, No. 11, Ed. 1 Thursday, March 11, 2004

Weekly newspaper from Rio Grande City, Texas that includes local, state and national news along with extensive advertising.
Date: March 11, 2004
Creator: Roberts, Kenneth
Object Type: Newspaper
System: The Portal to Texas History
Welfare Reform: An Issue Overview (open access)

Welfare Reform: An Issue Overview

None
Date: March 11, 2004
Creator: Burke, Vee
Object Type: Report
System: The UNT Digital Library
Stochastic Engine Final Report: Applying Markov Chain Monte Carlo Methods with Importance Sampling to Large-Scale Data-Driven Simulation (open access)

Stochastic Engine Final Report: Applying Markov Chain Monte Carlo Methods with Importance Sampling to Large-Scale Data-Driven Simulation

Accurate prediction of complex phenomena can be greatly enhanced through the use of data and observations to update simulations. The ability to create these data-driven simulations is limited by error and uncertainty in both the data and the simulation. The stochastic engine project addressed this problem through the development and application of a family of Markov Chain Monte Carlo methods utilizing importance sampling driven by forward simulators to minimize time spent search very large state spaces. The stochastic engine rapidly chooses among a very large number of hypothesized states and selects those that are consistent (within error) with all the information at hand. Predicted measurements from the simulator are used to estimate the likelihood of actual measurements, which in turn reduces the uncertainty in the original sample space via a conditional probability method called Bayesian inferencing. This highly efficient, staged Metropolis-type search algorithm allows us to address extremely complex problems and opens the door to solving many data-driven, nonlinear, multidimensional problems. A key challenge has been developing representation methods that integrate the local details of real data with the global physics of the simulations, enabling supercomputers to efficiently solve the problem. Development focused on large-scale problems, and on examining the …
Date: March 11, 2004
Creator: Glaser, R. E.; Johannesson, G.; Sengupta, S.; Kosovic, B.; Carle, S.; Franz, G. A. et al.
Object Type: Report
System: The UNT Digital Library
Spectroscopic Monitoring of Kidney Tissue Ischemic Injury (open access)

Spectroscopic Monitoring of Kidney Tissue Ischemic Injury

Noninvasive evaluation of tissue viability of donor kidneys used for transplantation is an issue that current technology is not able to address. In this work, we explore optical spectroscopy for its potential to assess the degree of ischemic damage in kidney tissue. We hypothesized that ischemic damage to kidney tissue will give rise to changes in its optical properties which in turn may be used to asses the degree of tissue injury. The experimental results demonstrate that the autofluorescence intensity of the injured kidney is decreasing as a function of time exposed to ischemic injury. Changes were also observed in the NIR light scattering intensities most probably arising from changes due to injury and death of the tissue.
Date: March 11, 2004
Creator: Demos, S G; Fitzgerald, J T; Michalopoulou, A P & Troppmann, C
Object Type: Article
System: The UNT Digital Library
Army Transformation and Modernization: Overview and Issues for Congress (open access)

Army Transformation and Modernization: Overview and Issues for Congress

This report briefly describes the modernization program for the U.S. military forces and discusses issues of feasibility, viability, and affordability of potential interest to Congress.
Date: March 11, 2004
Creator: Bruner, Edward F.
Object Type: Report
System: The UNT Digital Library
Determination of the Crevice Repassivation Potential of Alloy 22 by a Potentiodynamic-Galvanostatic-Potentiostatic Method (open access)

Determination of the Crevice Repassivation Potential of Alloy 22 by a Potentiodynamic-Galvanostatic-Potentiostatic Method

Alloy 22 (N06022) is a nickel-based alloy highly resistant to corrosion. In some aggressive conditions of high chloride concentration, temperature and applied potential, Alloy 22 may suffer crevice corrosion, a form of localized corrosion. There are several electrochemical methods that can be used to determine localized corrosion in metallic alloys. One of the most popular for rapid screening is the cyclic potentiodynamic polarization (CPP). This work compares the results obtained by measuring the localized corrosion resistance of Alloy 22 using both CPP and the more cumbersome Tsujikawa-Hisamatsu Electrochemical (THE) method. The electrolytes used were 1 M NaCl and 5 M CaCl{sub 2}, both at 90 C. Results show that similar repassivation potentials were obtained for Alloy 22 using both methods. That is, in cases where localized corrosion is observed using the fast CPP method, there is no need to use THE method since it takes ten times longer to obtain comparable results in spite that the mode of corrosion attack that results in the tested specimens are different.
Date: March 11, 2004
Creator: Evans, Kenneth J.; Wong, Lana L. & Rebak, Raul B.
Object Type: Article
System: The UNT Digital Library