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A Comprehensive Study of Surface Chemistry for Application to Engine NOx Aftertreatment (open access)

A Comprehensive Study of Surface Chemistry for Application to Engine NOx Aftertreatment

This work focuses on developing a scientific understanding of the processes associated with NO{sub x} trap operation. NO{sub x} traps are the most advanced technology for achieving future emissions standards with diesel engines. Successful development of NO{sub x} traps will allow widespread use of diesel engines in light-duty vehicles, reducing oil imports by as much as 60%. Diesel engines have a high efficiency and low maintenance that makes them the ideal choice for transportation applications. Use of diesel engines in all light-duty vehicles would reduce oil consumption in the USA by 30% and oil imports by 60%, considerably improving our energy security. For heavy trucks, there is no viable alternative to diesel engines. Only diesel engines can provide the necessary high efficiency and long life. These benefits are offset by high emission of pollutants. Diesel engines have high emissions of NO{sub x} and particulate matter. Over the last 20 years, EPA has been reducing allowable emissions from diesel engines, and NO{sub x} emissions are scheduled to be cut by a factor of 10 over the next 7 years. The target NO{sub x} emissions for year 2010 is 0.20 g/hp-hr. This value is well below 1 g/hp-hr, which has been identified …
Date: February 19, 2004
Creator: Aceves, S M; Piggot, T; Pitz, W; Mundy, C; Kuo, W & Havstad, M
Object Type: Report
System: The UNT Digital Library
Timpson & Tenaha News (Timpson, Tex.), Vol. 19, No. 6, Ed. 1 Thursday, February 19, 2004 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 19, No. 6, Ed. 1 Thursday, February 19, 2004

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: February 19, 2004
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Altus Times (Altus, Okla.), Vol. 105, No. 290, Ed. 1 Thursday, February 19, 2004 (open access)

Altus Times (Altus, Okla.), Vol. 105, No. 290, Ed. 1 Thursday, February 19, 2004

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: February 19, 2004
Creator: Andrews, Mike
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Dictyostelium discoideum cellulose synthase: Structure/function analysis and identification of interacting proteins (open access)

The Dictyostelium discoideum cellulose synthase: Structure/function analysis and identification of interacting proteins

OAK-B135 The major accomplishments of this project were: (1) the initial characterization of dcsA, the gene for the putative catalytic subunit of cellulose synthase in the cellular slime mold Dictyostelium discoideum; (2) the detection of a developmentally regulated event (unidentified, but perhaps a protein modification or association with a protein partner) that is required for cellulose synthase activity (i.e., the dcsA product is necessary, but not sufficient for cellulose synthesis); (3) the continued exploration of the developmental context of cellulose synthesis and DcsA; (4) the isolation of a GFP-DcsA-expressing strain (work in progress); and (5) the identification of Dictyostelium homologues for plant genes whose products play roles in cellulose biosynthesis. Although our progress was slow and many of our results negative, we did develop a number of promising avenues of investigation that can serve as the foundation for future projects.
Date: February 19, 2004
Creator: Blanton, Richard L.
Object Type: Report
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 89, No. 138, Ed. 1 Thursday, February 19, 2004 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 89, No. 138, Ed. 1 Thursday, February 19, 2004

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: February 19, 2004
Creator: Broaddus, Matthew B.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Perry Daily Journal (Perry, Okla.), Vol. 111, No. 33, Ed. 1 Thursday, February 19, 2004 (open access)

Perry Daily Journal (Perry, Okla.), Vol. 111, No. 33, Ed. 1 Thursday, February 19, 2004

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: February 19, 2004
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Canadian Record (Canadian, Tex.), Vol. 114, No. 8, Ed. 1 Thursday, February 19, 2004 (open access)

The Canadian Record (Canadian, Tex.), Vol. 114, No. 8, Ed. 1 Thursday, February 19, 2004

Weekly newspaper from Canadian, Texas that includes local, state and national news along with some advertising.
Date: February 19, 2004
Creator: Brown, Laurie Ezzell
Object Type: Newspaper
System: The Portal to Texas History
The Express-Star (Chickasha, Okla.), Ed. 1 Thursday, February 19, 2004 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Thursday, February 19, 2004

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: February 19, 2004
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Baytown Sun (Baytown, Tex.), Vol. 82, No. 79, Ed. 1 Thursday, February 19, 2004 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 82, No. 79, Ed. 1 Thursday, February 19, 2004

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: February 19, 2004
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
A Report on the use of Weak-Shock Wave Profiles and 3-D Dislocation Dynamics Simulations for Validation of Dislocation Multiplication and Mobility in the Phonon Drag Regime (open access)

A Report on the use of Weak-Shock Wave Profiles and 3-D Dislocation Dynamics Simulations for Validation of Dislocation Multiplication and Mobility in the Phonon Drag Regime

Dynamically loaded gas gun experiments were performed to validate the predictive capabilities of 3-D dislocation dynamics (DD) code simulations at very high strain rates and dislocation velocities where the phonon drag mechanism will be dominant. Experiments were performed in the weak-shock regime on high-purity Mo single crystals with [001] compression axes. We have also performed shock-recovery experiments and are in the process of analyzing the dislocation structure generated by the weak-shock using transmission electron microscopy (TEM), which will also be used to validate the dislocation structure predicted by the DD simulations. The DD simulations being performed at Washington State University by Prof. H. Zbib and co-workers will be compared to the experimentally measured wave profiles, thereby validating mechanisms of dislocation generation and motion. Some DD simulation results are presented to demonstrate the feasibility of using a combined experimental/simulation effort for the validation of dislocation generation and mobility physics issues in the phonon drag regime.
Date: February 19, 2004
Creator: Cazamias, J; Lassila, D; Shehadeh, M & Zbib, H
Object Type: Report
System: The UNT Digital Library
Today Cedar Hill (Duncanville, Tex.), Vol. 38, No. 47, Ed. 1 Thursday, February 19, 2004 (open access)

Today Cedar Hill (Duncanville, Tex.), Vol. 38, No. 47, Ed. 1 Thursday, February 19, 2004

Weekly newspaper published in Duncanville, Texas that includes local Cedar Hill, state, and national news along with advertising.
Date: February 19, 2004
Creator: Gooch, Robin
Object Type: Newspaper
System: The Portal to Texas History
Quantifying human vitamin kinetics using AMS (open access)

Quantifying human vitamin kinetics using AMS

Tracing vitamin kinetics at physiologic concentrations has been hampered by a lack of quantitative sensitivity for chemically equivalent tracers that could be used safely in healthy people. Instead, elderly or ill volunteers were sought for studies involving pharmacologic doses with radioisotopic labels. These studies fail to be relevant in two ways: vitamins are inherently micronutrients, whose biochemical paths are saturated and distorted by pharmacological doses; and while vitamins remain important for health in the elderly or ill, their greatest effects may be in preventing slow and cumulative diseases by proper consumption throughout youth and adulthood. Neither the target dose nor the target population are available for nutrient metabolic studies through decay counting of radioisotopes at high levels. Stable isotopic labels are quantified by isotope ratio mass spectrometry at levels that trace physiologic vitamin doses, but the natural background of stable isotopes severely limits the time span over which the tracer is distinguishable. Indeed, study periods seldom ranged over a single biological mean life of the labeled nutrients, failing to provide data on the important final elimination phase of the compound. Kinetic data for the absorption phase is similarly rare in micronutrient research because the phase is rapid, requiring many consecutive …
Date: February 19, 2004
Creator: Hillegonds, Darren; Dueker, Stephen R.; Ognibene, Ted; Buchholz, Bruce A.; Lin, Yumei; Vogel, John S. et al.
Object Type: Article
System: The UNT Digital Library
Garber Billings News (Garber, Okla.), Vol. 104, No. 17, Ed. 1 Thursday, February 19, 2004 (open access)

Garber Billings News (Garber, Okla.), Vol. 104, No. 17, Ed. 1 Thursday, February 19, 2004

Weekly newspaper from Garber, Oklahoma that includes local, state, and national news along with advertising.
Date: February 19, 2004
Creator: Hogan, Vickie Lee
Object Type: Newspaper
System: The Gateway to Oklahoma History
Observation of Fluorine-Vacancy Complexes in Silicon (open access)

Observation of Fluorine-Vacancy Complexes in Silicon

We show direct evidence, obtained by positron annihilation spectroscopy, for the complexing of fluorine with vacancies in silicon. Both float zone and Czochralski silicon wafers were implanted with 30 keV fluorine ions to a fluence of 2x10{sup 14} ions/cm{sup 2}, and studied in the as-implanted condition, and after annealing to 650o C for 10 and for 30 minutes. The ''2-detector'' background reduction technique for positron annihilation was applied. The spectra reveal a significant concentration of fluorine-vacancy complexes after annealing, for both Czochralski and float zone material, supporting the results of computer simulations of the implantation and annealing process.
Date: February 19, 2004
Creator: Jenei, Z.; Simpson, P. J.; Robison, R. R.; Asoka-Kumar, P. & Law, M. E.
Object Type: Article
System: The UNT Digital Library
Port Aransas South Jetty (Port Aransas, Tex.), Vol. 34, No. 08, Ed. 1 Thursday, February 19, 2004 (open access)

Port Aransas South Jetty (Port Aransas, Tex.), Vol. 34, No. 08, Ed. 1 Thursday, February 19, 2004

Weekly newspaper from Port Aransas, Texas on Mustang Island that includes local, state and national news along with advertising.
Date: February 19, 2004
Creator: Judson, Mary
Object Type: Newspaper
System: The Portal to Texas History
Spring [2004] Visitors' Guide (Port Aransas, Tex.) (open access)

Spring [2004] Visitors' Guide (Port Aransas, Tex.)

Spring visitors' guide from Port Aransas, Texas that includes information of interest to visitors along with extensive advertising.
Date: February 19, 2004
Creator: Judson, Mary Henkel
Object Type: Newspaper
System: The Portal to Texas History
Anomalous Skin Effect for Anisotropic Electron Velocity Distribution Function (open access)

Anomalous Skin Effect for Anisotropic Electron Velocity Distribution Function

The anomalous skin effect in a plasma with a highly anisotropic electron velocity distribution function (EVDF) is very different from skin effect in a plasma with the isotropic EVDF. An analytical solution was derived for the electric field penetrated into plasma with the EVDF described as a Maxwellian with two temperatures Tx >> Tz, where x is the direction along the plasma boundary and z is the direction perpendicular to the plasma boundary. The skin layer was found to consist of two distinctive regions of width of order nTx/w and nTz/w, where nTx,z/w = (Tx,z/m)1/2 is the thermal electron velocity and w is the incident wave frequency.
Date: February 19, 2004
Creator: Kaganovich, Igor; Startsev, Edward & Shvets, Gennady
Object Type: Report
System: The UNT Digital Library
The Budget Reconciliation Process: The Senate's "Byrd" Rule (open access)

The Budget Reconciliation Process: The Senate's "Byrd" Rule

Reconciliation is a procedure under the Congressional Budget Act of 1974 by which Congress implements budget resolution policies affecting mainly permanent spending and revenue programs. The principal focus in the reconciliation process has been deficit reduction, but in recent years reconciliation has encompassed revenue reduction generally and spending increases in selected program areas. The Byrd rule provides six definitions of what constitutes extraneous matter for purposes of the rule (and several exceptions thereto), but the term is generally described as covering provisions unrelated to achieving the goals of the reconciliation instructions.
Date: February 19, 2004
Creator: Keith, Robert
Object Type: Report
System: The UNT Digital Library
The Oklahoma Daily (Norman, Okla.), Vol. 87, No. 107, Ed. 1 Thursday, February 19, 2004 (open access)

The Oklahoma Daily (Norman, Okla.), Vol. 87, No. 107, Ed. 1 Thursday, February 19, 2004

Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date: February 19, 2004
Creator: King, Christopher R.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Electroweak Symmetry Breaking via UV Insensitive Anomaly Mediation (open access)

Electroweak Symmetry Breaking via UV Insensitive Anomaly Mediation

Anomaly mediation solves the supersymmetric flavor and CP problems. This is because the superconformal anomaly dictates that supersymmetry breaking is transmitted through nearly flavor-blind infrared physics that is highly predictive and UV insensitive. Slepton mass squareds, however, are predicted to be negative. This can be solved by adding D-terms for U(1)_Y and U(1)_{B-L} while retaining the UV insensitivity. In this paper we consider electroweak symmetry breaking via UV insensitive anomaly mediation in several models. For the MSSM we find a stable vacuum when tanbeta< 1, but in this region the top Yukawa coupling blows up only slightly above the supersymmetry breaking scale. For the NMSSM, we find a stable electroweak breaking vacuum but with a chargino that is too light. Replacing the cubic singlet term in the NMSSM superpotential with a term linear in the singlet wefind a stable vacuum and viable spectrum. Most of the parameter region with correct vacua requires a large superpotential coupling, precisely what is expected in the"Fat Higgs'" model in which the superpotential is generated dynamically. We have therefore found the first viable UV complete, UV insensitive supersymmetry breaking model that solves the flavor and CP problems automatically: the Fat Higgs model with UV insensitive …
Date: February 19, 2004
Creator: Kitano, Ryuichiro; Kribs, Graham D. & Murayama, Hitoshi
Object Type: Article
System: The UNT Digital Library
Heat Transfer Analysis for a Fixed CST Column (open access)

Heat Transfer Analysis for a Fixed CST Column

In support of a small column ion exchange (SCIX) process for the Savannah River Site waste processing program, a transient two-dimensional heat transfer model that includes the conduction process neglecting the convection cooling mechanism inside the crystalline silicotitanate (CST) column has been constructed and heat transfer calculations made for the present design configurations. For this situation, a no process flow condition through the column was assumed as one of the reference conditions for the simulation of a loss-of-flow accident. A series of the modeling calculations has been performed using a computational heat transfer approach. Results for the baseline model indicate that transit times to reach 130 degrees Celsius maximum temperature of the CST-salt solution column are about 96 hours when the 20-in CST column with 300 Ci/liter heat generation source and 25 degrees Celsius initial column temperature is cooled by natural convection of external air as a primary heat transfer mechanism. The modeling results for the 28-in column equipped with water jacket systems on the external wall surface of the column and water coolant pipe at the center of the CST column demonstrate that the column loaded with 300 Ci/liter heat source can be maintained non-boiling indefinitely. Sensitivity calculations for …
Date: February 19, 2004
Creator: Lee, Si Young
Object Type: Report
System: The UNT Digital Library
Archer County News (Archer City, Tex.), No. 8, Ed. 1 Thursday, February 19, 2004 (open access)

Archer County News (Archer City, Tex.), No. 8, Ed. 1 Thursday, February 19, 2004

Weekly newspaper from Archer City, Texas that includes local, state, and national news along with advertising.
Date: February 19, 2004
Creator: Lewis, Shelley
Object Type: Newspaper
System: The Portal to Texas History
PRELIMINARY FIELD EVALUATION OF MERCURY CONTROL USING COMBUSTION MODIFICATIONS (open access)

PRELIMINARY FIELD EVALUATION OF MERCURY CONTROL USING COMBUSTION MODIFICATIONS

In this project General Electric Energy and Environmental Research Corporation conducts a preliminary field evaluation of a novel technology, referred to as Hg/NO{sub x}, that can reduce emissions of both mercury (Hg) and oxides of nitrogen (NO{sub x}) from coal-fired power plants. The evaluation takes place in Green Station Unit 2 operated by Western Kentucky Energy. Reduction of Hg and NO{sub x} emissions in Unit 2 is achieved using coal reburning. Activities during first project year (January 23, 2003--January 22, 2004) included measurements of baseline Hg emissions in Unit 2 and pilot-scale testing. Baseline testing of Hg emissions in Green Unit 2 has been completed. Two fuels were tested with OFA system operating at minimum air flow. Mercury emissions were measured at ESP inlet and outlet, and at the stack using Ontario Hydro revised method. Testing demonstrated that baseline Hg reductions at ESP outlet and stack were 30-45% and 70-80%, respectively. Pilot-scale testing demonstrated good agreement with baseline measurements in Unit 2. Testing showed that fuel composition had an effect on the efficiency of Hg absorption on fly ash. Maximum achieved Hg removal in reburning was close to 90%. Maximum achieved Hg reduction at air staging conditions was 60%. Testing …
Date: February 19, 2004
Creator: Lissianski, Vitali & Marquez, Antonio
Object Type: Report
System: The UNT Digital Library
CO2 SELECTIVE CERAMIC MEMBRANE FOR WATER-GAS SHIFT REACTION WITH CONCOMITANT RECOVERY OF CO2 (open access)

CO2 SELECTIVE CERAMIC MEMBRANE FOR WATER-GAS SHIFT REACTION WITH CONCOMITANT RECOVERY OF CO2

Two process schemes have been investigated by us for the use of hydrotalcites we prepared as CO{sub 2} adsorbents to enhance water gas shift (WGS) reaction: Case I involves the adsorption enhanced WGS packed bed reactor and Case II involves the adsorption enhanced WGS membrane reactor. Both cases will achieve the same objective as the hydrotalcite membrane reactor: i.e., improving the WGS reactor efficiency via the concomitant removal of CO{sub 2} for sequestration. In this report a detailed investigation of the design characteristics and performance of Case II, termed the Hybrid Adsorbent-Membrane Reactor (HAMR), is presented. The HAMR system includes a packed-bed catalytic membrane reactor (hydrogen selective) coupling the WGS reaction (in a porous hydrogen selective membrane) with CO{sub 2} removal with an adsorbent in the permeate side. The reactor characteristics have been investigated for a range of permeance and selectivity relevant to the aforementioned application. The HAMR system shows enhanced CO conversion, hydrogen yield, and product purity, and provides good promise for reducing the hostile operating conditions of conventional WGS reactors, and for meeting the CO{sub 2} sequestration objective. In the next quarterly report we will present the simulation result for Case I as well as the progress on …
Date: February 19, 2004
Creator: Liu, Paul K. T.
Object Type: Report
System: The UNT Digital Library