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CATALYSIS SCIENCE AND TECHNOLOGY (open access)

CATALYSIS SCIENCE AND TECHNOLOGY

This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Our objectives were to develop a multidisciplinary team and capabilities to develop a fundamental understanding of homogeneous, heterogeneous, and heterogenized catalysts. With the aid of theoretical chemistry approaches we explored and characterized the chemical reactivity and physical properties of a large number of catalytic systems.
Date: August 1, 2000
Creator: ABRAMS, M.; BAKER, R. & AL, ET
Object Type: Report
System: The UNT Digital Library
INVESTIGATION OF HALO FORMATION IN CONTINUOUS BEAMS USING WEIGHTED POLYNOMIAL EXPANSIONS AND PERTURBATIONAL ANALYSIS (open access)

INVESTIGATION OF HALO FORMATION IN CONTINUOUS BEAMS USING WEIGHTED POLYNOMIAL EXPANSIONS AND PERTURBATIONAL ANALYSIS

We consider halo formation in continuous beams oscillating at natural modes by inspecting particle trajectories. Trajectory equations containing field nonlinearities are derived from a weighted polynomial expansion. We then use perturbational techniques to further analyze particle motion.
Date: August 1, 2000
Creator: ALLEN, C.
Object Type: Article
System: The UNT Digital Library
The Law of Church and State: Public Aid to Sectarian Schools (open access)

The Law of Church and State: Public Aid to Sectarian Schools

One of the most difficult issues of constitutional law concerns the extent to which the establishment of religion clause of the First Amendment imposes constraints on the provision of public aid to private sectarian schools. This report gives a brief overview of the evolution of the Court’s interpretation of the establishment clause in this area and itemizes the categories of aid that have been addressed by the Court and held to be constitutionally permissible or impermissible, both at the elementary and secondary school level and at the college level.
Date: August 1, 2000
Creator: Ackerman, David M.
Object Type: Report
System: The UNT Digital Library
Cast Metal Coalition Research and Development Closeout Report (open access)

Cast Metal Coalition Research and Development Closeout Report

The Cast Metal Coalition, composed of more than 22 research providers and universities and 149 industrial partners, has completed a four-year research and development partnership with the Department of Energy. This report provides brief summaries of the 29 projects performed by the Coalition. These projects generated valuable information in such aspects of the metals industry as process prediction technologies, quality control, improved alloys, product machinability, and casting process improvements.
Date: August 1, 2000
Creator: Allen, D.
Object Type: Report
System: The UNT Digital Library
Medical applications of nuclear physics and heavy-ion beams (open access)

Medical applications of nuclear physics and heavy-ion beams

Isotopes and accelerators, hallmarks of nuclear physics, are finding increasingly sophisticated and effective applications in the medical field. Diagnostic and therapeutic uses of radioisotopes are now a $10B/yr business worldwide, with over 10 million procedures and patient studies performed every year. This paper will discuss the use of isotopes for these applications. In addition, beams of protons and heavy ions are being more and more widely used clinically for treatment of malignancies. To be discussed here as well will be the rationale and techniques associated with charged-particle therapy, and the progress in implementation and optimization of these technologies for clinical use.
Date: August 1, 2000
Creator: Alonso, Jose R.
Object Type: Article
System: The UNT Digital Library
IDENTIFICATION OF NONLINEARITIES IN AN 8-DOF SYSTEM THROUGH SPECTRAL FEEDBACK (open access)

IDENTIFICATION OF NONLINEARITIES IN AN 8-DOF SYSTEM THROUGH SPECTRAL FEEDBACK

The accurate detection and characterization of nonlinearities associated with damage in structural systems is an area of vibration analysis that is being widely researched. In this paper, nonlinear behavior is considered a potential indicator of damage. Most conventional damage detection methods, such as those based on resonant frequencies and mode shapes, do not accurately identify the location and extent of nonlinearities present in a given structural system. As an extension of previous work at LANL, an effort is made to validate a damage detection method proposed by Adams. This method states that the frequency response function (FRF) matrix obtained from a low-level vibration test approximates the underlying linear FRF matrix of the system. The nonlinear systems' responses to high level excitation are combined with the linear FRF in a classic feedback loop to obtain the contributions of nonlinear internal forces. The temporal and spatial characteristics of the nonlinearities present in a structural system are identified. An 8-DOF system is used as a test case to validate the aforementioned method. Results of the tests and important issues concerning the method are presented.
Date: August 1, 2000
Creator: Arcand, B. & Wait, J.
Object Type: Article
System: The UNT Digital Library
Chemical Conversion of TNT: Production of 2,4,6-Trinitrobenzoic Acid (open access)

Chemical Conversion of TNT: Production of 2,4,6-Trinitrobenzoic Acid

None
Date: August 1, 2000
Creator: Asrat'ev, A.A.; Marchukov, V.A.; Suschev, V.G.; Aleksandrov, A.V.; Semenov, V.V.; Buchanan, A.C. et al.
Object Type: Report
System: The UNT Digital Library
{sup 3}He MAGNETOMETRY FOR A NEUTRON EDM MEASUREMENT (open access)

{sup 3}He MAGNETOMETRY FOR A NEUTRON EDM MEASUREMENT

The behavior of small amounts of polarized {sup 3}He in a bath of superfluid {sup 4}He at temperatures below 1 K is critical to a new technique for measuring the EDM of the neutron. We report on studies to enhance the number of ultracold neutrons produced in such a bath, on the development of neutron tomography in gaseous mixtures, on magnet properties associated with the precession of {sup 3}He, and on preparations for tests of the distribution and diffusion coefficients of {sup 3}He in the bath.
Date: August 1, 2000
Creator: BANGERT, P. & AL, ET
Object Type: Report
System: The UNT Digital Library
A Risk Assessment Methodology for Physical Security (open access)

A Risk Assessment Methodology for Physical Security

None
Date: August 1, 2000
Creator: BIRINGER,BETTY E.
Object Type: Article
System: The UNT Digital Library
OPTIMIZING THROUGH CO-EVOLUTIONARY AVALANCHES (open access)

OPTIMIZING THROUGH CO-EVOLUTIONARY AVALANCHES

We explore a new general-purpose heuristic for finding high-quality solutions to hard optimization problems. The method, called extremal optimization, is inspired by ''self-organized critically,'' a concept introduced to describe emergent complexity in many physical systems. In contrast to Genetic Algorithms which operate on an entire ''gene-pool'' of possible solutions, extremal optimization successively replaces extremely undesirable elements of a sub-optimal solution with new, random ones. Large fluctuations, called ''avalanches,'' ensue that efficiently explore many local optima. Drawing upon models used to simulate far-from-equilibrium dynamics, extremal optimization complements approximation methods inspired by equilibrium statistical physics, such as simulated annealing. With only one adjustable parameter, its performance has proved competitive with more elaborate methods, especially near phase transitions. Those phase transitions are found in the parameter space of most optimization problems, and have recently been conjectured to be the origin of some of the hardest instances in computational complexity. We will demonstrate how extremal optimization can be implemented for a variety of combinatorial optimization problems. We believe that extremal optimization will be a useful tool in the investigation of phase transitions in combinatorial optimization problems, hence valuable in elucidating the origin of computational complexity.
Date: August 1, 2000
Creator: BOETTCHER, S. & PERCUS, A.
Object Type: Article
System: The UNT Digital Library
DOE-EM SNF Transportation System (open access)

DOE-EM SNF Transportation System

None
Date: August 1, 2000
Creator: BREIVIK,NICOLE L. & AMMERMAN,DOUGLAS J.
Object Type: Report
System: The UNT Digital Library
LESSONS FROM HADRON PHENOMENOLOGY (open access)

LESSONS FROM HADRON PHENOMENOLOGY

Meson spectra can be well approximated by a specific form of a nonlinear Regge trajectory which is consistent with a finite number of bound states. This may have important consequences for experiment, and may be a hint for the theory.
Date: August 1, 2000
Creator: BRISUDOVA, M.; BUAKOVSKY, L. & GOLDMAN, T.
Object Type: Article
System: The UNT Digital Library
PRELIMINARY PROJECT PLAN FOR LANSCE INTEGRATED FLIGHT PATHS 11A, 11B, 12, and 13 (open access)

PRELIMINARY PROJECT PLAN FOR LANSCE INTEGRATED FLIGHT PATHS 11A, 11B, 12, and 13

This Preliminary Project Plan Summarizes the Technical, Cost, and Schedule baselines for an integrated approach to developing several flight paths at the Manual Lujan Jr. Neutron Scattering Center at the Los Alamos Neutron Science Center. For example, the cost estimate is intended to serve only as a rough order of magnitude assessment of the cost that might be incurred as the flight paths are developed. Further refinement of the requirements and interfaces for each beamline will permit additional refinement and confidence in the accuracy of all three baselines (Technical, Cost, Schedule).
Date: August 1, 2000
Creator: BULTMAN, D. H. & CORP., D. WEINACHT - AIRES
Object Type: Report
System: The UNT Digital Library
Oak Ridge Y-12 Plant Emergency Action Level (EAL) Process (open access)

Oak Ridge Y-12 Plant Emergency Action Level (EAL) Process

This report establishes requirements and standard methods for the development and maintenance of the Emergency Action Level (EAL) Process used by all lead and event contractors for emergency planning and preparedness. The EAL process ensures a technically defensible approach to emergency categorization/classification in accordance with DOE Order 151.1. The instructions provided in this document include methods and requirements for the development and approval of the EAL process. EALs are developed to cover events inside and outside the Y-12 Plant and to allow the Emergency Response Organization (ERO) to classify or reclassify events promptly based on specific indicators. This report is divided into the following 11 subsections: (1) EAL Process, (2) Categorization/Classification System for Operational Emergencies, (3) Development of EALs, (4) Barrier Analysis for EALs, (5) Symptom-Based and Event-Based EALs, (6) Other Considerations, (7) Integration of EALs with Normal and Off-Normal Operations, (8) EAL Manual, (9) Testing EALs for Completeness, (10) Training and Implementation of EALs, and (11) Configuration Management.
Date: August 1, 2000
Creator: Bailiff, E. G. & Bolling, J. D.
Object Type: Report
System: The UNT Digital Library
Americium Separations From Nitric Acid Process Effluent Streams (open access)

Americium Separations From Nitric Acid Process Effluent Streams

The aging of the US nuclear stockpile presents a number of challenges, including the ever-increasing radioactivity of plutonium residues from {sup 241}Am. Minimization of this weak gamma-emitter in process and waste solutions is desirable to reduce both worker exposure and the effects of radiolysis on the final waste product. Removal of americium from plutonium nitric acid processing effluents, however, is complicated by the presence of large.quantities of competing metals, particularly Fe and Al, and-strongly oxidizing acidic solutions. The reprocessing operation offers several points at which americium removal maybe attempted, and we are evaluating two classes of materials targeted at different steps in the process. Extraction chromatography resin materials loaded with three different alkylcarbamoyl phosphinates and phosphine oxides were accessed for Am removal efficiency and Am/Fe selectivity from 1-7 molar nitric acid solutions. Commercial and experimental mono- and bifunctional anion-exchange resins were evaluated for total alpha-activity removal from post-evaporator solutions whose composition, relative to the original nitric acid effluent, is reduced in acid and greatly increased in total salt content. With both classes of materials, americium/total alpha emission removal is sufficient to meet regulatory requirements even under sub-optimal conditions. Batch distribution coefficients, column performance data, and the effects of Fe-masking agents …
Date: August 1, 2000
Creator: Barr, M. & Jarvinen, G.
Object Type: Article
System: The UNT Digital Library
Qsar of Distribution Coefficients for Pu (no3)062-Complexes Using Molecular Mechanics (open access)

Qsar of Distribution Coefficients for Pu (no3)062-Complexes Using Molecular Mechanics

Computer-aided modeling has been very successful in the design of chelating ligands for the formation of selective metal complexes. We report herein preliminary efforts to extend the principles developed for ion-specific chelating ligands to the weaker, more diffuse electrostatic interactions between complex anions and dicationic sites of anion-exchange resins. Calculated electrostatic affinity between plutonium (IV) hexanitrato dianions and analogue of dicationic anion-exchange sites correlate well with empirically-determined distribution coefficients. This Quantitative Structure Activity Relationship (QSAR) is useful in the determination of the overall trend within a select series of bifunctional resins and which structural modifications are most likely to be advantageous. Ultimately, we hope to refine this methodology to allow the a priori determination of ion-exchange behavior for abroad class of materials.
Date: August 1, 2000
Creator: Barr, M.; Jarvinen, G. & Moody, E.
Object Type: Article
System: The UNT Digital Library
Ash Deposit Formation and Deposit Properties. A Comprehensive Summary of Research Conducted at Sandia's Combustion Research Facility (open access)

Ash Deposit Formation and Deposit Properties. A Comprehensive Summary of Research Conducted at Sandia's Combustion Research Facility

This report summarizes experimental and theoretical work performed at Sandia's Combustion Research Facility over the past eight years on the fate of inorganic material during coal combustion. This work has been done under four broad categories: coal characterization, fly ash formation, ash deposition, and deposit property development. The objective was to provide sufficient understanding of these four areas to be able to predict coal behavior in current and advanced conversion systems. This work has led to new characterization techniques for fuels that provide, for the first time, systematic and species specific information regarding the inorganic material. The transformations of inorganic material during combustion can be described in terms of the net effects of the transformations of these individual species. Deposit formation mechanisms provide a framework for predicting deposition rates for abroad range of particle sizes. Predictions based on these rates many times are quite accurate although there are important exceptions. A rigorous framework for evaluating deposit has been established. Substantial data have been obtained with which to exercise this framework, but this portion of the work is less mature than is any other. Accurate prediction of deposit properties as functions of fuel properties, boiler design, and boiler operating conditions represents …
Date: August 1, 2000
Creator: Baxter, Larry L.
Object Type: Report
System: The UNT Digital Library
Carbon dioxide reuse and sequestration: The state of the art today (open access)

Carbon dioxide reuse and sequestration: The state of the art today

Atmospheric concentrations of CO{sub 2} and other greenhouse gases (GHGs) are growing steadily. GHG levels seem likely to grow more quickly in the future as developed countries continue to use large amounts of energy, while developing countries become wealthy enough to afford energy-intensive automobiles, refrigerators, and other appliances (as well as live and work in larger, more comfortable structures). To keep GHGs at manageable levels, large decreases in CO{sub 2} emissions will be required. Yet analysts understand the difficulty of developing enough zero- and low-carbon-emission technologies to meet the goal of safe GHG stabilization. Carbon sequestration technologies can help bridge this gap. These technologies are only beginning to be developed, but their promise is already evident. In Europe, CO{sub 2} has been continuously and safely pumped into a below-sea limestone structure for over three years, where it remains. In New Mexico, CO{sub 2} is being used to drive out natural gas from within unminable coal seams 1,000 meters below the surface, and again, continuously injected CO{sub 2} has stayed sequestered for over three years, even though the project was designed for natural gas production, not CO{sub 2} sequestration. These and other beginnings suggest that much CO{sub 2} could be reused …
Date: August 1, 2000
Creator: Benson, Sally M.; Dorchak, Thomas; Jacobs, Gary; Ekmann, James; Bishop, Jim & Grahame, Thomas
Object Type: Article
System: The UNT Digital Library
The Harper Herald (Harper, Tex.), Vol. 70, No. 29, Ed. 1 Tuesday, August 1, 2000 (open access)

The Harper Herald (Harper, Tex.), Vol. 70, No. 29, Ed. 1 Tuesday, August 1, 2000

Weekly newspaper from Harper, Texas that includes local, state, and national news along with advertising.
Date: August 1, 2000
Creator: Bishop, Karen
Object Type: Newspaper
System: The Portal to Texas History
Opening the ultra high energy cosmic ray window from the top (open access)

Opening the ultra high energy cosmic ray window from the top

While several arguments can be proposed against the existence of particles with energy in excess of (3--5) x 10{sup 19} eV in the cosmic ray spectrum, these particles are actually observed and their origin seeks for an explanation. After a description of the problems encountered in explaining these ultra-high energy cosmic rays (UHECRs) in the context of astrophysical sources, the authors review the so-called Top-Down (TD) Models, in which UHECRs are the result of the decay of very massive unstable particles, possibly created in the Early Universe. Particular emphasis will be given to the signatures of the TD models, likely to be accessible to upcoming experiments like Auger.
Date: August 1, 2000
Creator: Blasi, Pasquale
Object Type: Article
System: The UNT Digital Library
Lifetime testing 700 MHz rf windows for the accelerator production of tritium program (open access)

Lifetime testing 700 MHz rf windows for the accelerator production of tritium program

None
Date: August 1, 2000
Creator: Borrego, M.
Object Type: Article
System: The UNT Digital Library
Upgraded Calibrations of the Thomson System at DIII-D (open access)

Upgraded Calibrations of the Thomson System at DIII-D

The DIII-D Thomson system measures electron density and temperature with eight pulsed ND:YAG lasers along three paths through the plasma vessel. The components of the Thomson system are absolutely calibrated so the measurements can be combined into a single profile from a normalized plasma radius ({rho}) of about 0.1 to the edge of the plasma. A monochromator calibration and opto-electronic calibration measure the detectors' absolute sensitivity to background and pulsed light. A Rayleigh scattering calibration and transmission calibrations measure the transmission of light to the detectors. The calibration systems are being upgraded to reduce the effect of systematic errors on the temperature and density measurements. The systematic errors can be checked by a comparison of overlapping channels and estimated from fits to the profiles. The contributions of the systematic uncertainties relative to the statistical uncertainties of the measurement are discussed through simulations and experimental data.
Date: August 1, 2000
Creator: Bray, B.; Hsieh, C.; Carlstrom, T. N. & Makariou, C. C.
Object Type: Article
System: The UNT Digital Library
["A Gay Old Party" article, August 1, 2000] (open access)

["A Gay Old Party" article, August 1, 2000]

An article, written by David Brooks for The Weekly Standard, about a recent lunch get-together for gay and lesbian Republicans. It also focuses on Charles C. Francis and his role in Republican circles.
Date: August 1, 2000
Creator: Brooks, David
Object Type: Clipping
System: The UNT Digital Library
Weld Properties of a Free Machining Stainless Steel (open access)

Weld Properties of a Free Machining Stainless Steel

The all weld metal tensile properties from gas tungsten arc and electron beam welds in free machining austenitic stainless steels have been determined. Ten heats with sulfur contents from 0.04 to 0.4 wt.% and a wide range in Creq/Nieq ratios were studied. Tensile properties of welds with both processes were related to alloy composition and solidification microstructure. The yield and ultimate tensile strengths increased with increasing Creq/Nieq ratios and ferrite content, whereas the ductility measured by RA at fracture decreased with sulfur content. Nevertheless, a range in alloy compositions was identified that provided a good combination of both strength and ductility. The solidification cracking response for the same large range of compositions are discussed, and compositions identified that would be expected to provide good performance in welded applications.
Date: August 1, 2000
Creator: Brooks, J. A.; Goods, S. H. & Robino, C. V.
Object Type: Report
System: The UNT Digital Library