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CARBON DIOXIDE AS A FEEDSTOCK. (open access)

CARBON DIOXIDE AS A FEEDSTOCK.

This report is an overview on the subject of carbon dioxide as a starting material for organic syntheses of potential commercial interest and the utilization of carbon dioxide as a substrate for fuel production. It draws extensively on literature sources, particularly on the report of a 1999 Workshop on the subject of catalysis in carbon dioxide utilization, but with emphasis on systems of most interest to us. Atmospheric carbon dioxide is an abundant (750 billion tons in atmosphere), but dilute source of carbon (only 0.036 % by volume), so technologies for utilization at the production source are crucial for both sequestration and utilization. Sequestration--such as pumping CO{sub 2} into sea or the earth--is beyond the scope of this report, except where it overlaps utilization, for example in converting CO{sub 2} to polymers. But sequestration dominates current thinking on short term solutions to global warming, as should be clear from reports from this and other workshops. The 3500 million tons estimated to be added to the atmosphere annually at present can be compared to the 110 million tons used to produce chemicals, chiefly urea (75 million tons), salicylic acid, cyclic carbonates and polycarbonates. Increased utilization of CO{sub 2} as a starting …
Date: December 9, 2000
Creator: CREUTZ,C. & FUJITA,E.
System: The UNT Digital Library
CARBON DIOXIDE AS A FEEDSTOCK. (open access)

CARBON DIOXIDE AS A FEEDSTOCK.

This report is an overview on the subject of carbon dioxide as a starting material for organic syntheses of potential commercial interest and the utilization of carbon dioxide as a substrate for fuel production. It draws extensively on literature sources, particularly on the report of a 1999 Workshop on the subject of catalysis in carbon dioxide utilization, but with emphasis on systems of most interest to us. Atmospheric carbon dioxide is an abundant (750 billion tons in atmosphere), but dilute source of carbon (only 0.036 % by volume), so technologies for utilization at the production source are crucial for both sequestration and utilization. Sequestration--such as pumping CO{sub 2} into sea or the earth--is beyond the scope of this report, except where it overlaps utilization, for example in converting CO{sub 2} to polymers. But sequestration dominates current thinking on short term solutions to global warming, as should be clear from reports from this and other workshops. The 3500 million tons estimated to be added to the atmosphere annually at present can be compared to the 110 million tons used to produce chemicals, chiefly urea (75 million tons), salicylic acid, cyclic carbonates and polycarbonates. Increased utilization of CO{sub 2} as a starting …
Date: December 9, 2000
Creator: CREUTZ,C. & FUJITA,E.
System: The UNT Digital Library
Comparison of Finite Element Predictions to Measurements from the Sandia Microslip Experiment (open access)

Comparison of Finite Element Predictions to Measurements from the Sandia Microslip Experiment

When embarking on an experimental program for purposes of discovery and understanding, it is only prudent to use appropriate analysis tools to aid in the discovery process. Due to the limited scope of experimental measurement analytical results can significantly complement the data after a reasonable validation process has occurred. In this manner the analytical results can help to explain certain measurements, suggest other measurements to take and point to possible modifications to the experimental apparatus. For these reasons it was decided to create a detailed nonlinear finite element model of the Sandia Microslip Experiment. This experiment was designed to investigate energy dissipation due to microslip in bolted joints and to identify the critical parameters involved. In an attempt to limit the microslip to a single interface a complicated system of rollers and cables was devised to clamp the two slipping members together with a prescribed normal load without using a bolt. An oscillatory tangential load is supplied via a shaker. The finite element model includes the clamping device in addition to the sequence of steps taken in setting up the experiment. The interface is modeled using Coulomb friction requiring a modest validation procedure for estimating the coefficient of friction. Analysis …
Date: November 9, 2000
Creator: LOBITZ,DONALD W.; GREGORY,DANNY LYNN & SMALLWOOD,DAVID O.
System: The UNT Digital Library
Component Technology for High-Performance Scientific Simulation Software (open access)

Component Technology for High-Performance Scientific Simulation Software

We are developing scientific software component technology to manage the complexity of modem, parallel simulation software and increase the interoperability and re-use of scientific software packages. In this paper, we describe a language interoperability tool named Babel that enables the creation and distribution of language-independent software libraries using interface definition language (IDL) techniques. We have created a scientific IDL that focuses on the unique interface description needs of scientific codes, such as complex numbers, dense multidimensional arrays, complicated data types, and parallelism. Preliminary results indicate that in addition to language interoperability, this approach provides useful tools for thinking about the design of modem object-oriented scientific software libraries. Finally, we also describe a web-based component repository called Alexandria that facilitates the distribution, documentation, and re-use of scientific components and libraries.
Date: November 9, 2000
Creator: Epperly, T; Kohn, S & Kumfert, G
System: The UNT Digital Library
The Development of the Yucca Mountain Project Feature, Event, and Process (FEP) Database (open access)

The Development of the Yucca Mountain Project Feature, Event, and Process (FEP) Database

None
Date: November 9, 2000
Creator: FREEZE,GEOFF; SWIFT,PETER N. & BRODSKY,NANCY S.
System: The UNT Digital Library
Differencing Algorithms for Material Interfaces in Two-Phase Darcy Flow (open access)

Differencing Algorithms for Material Interfaces in Two-Phase Darcy Flow

None
Date: November 9, 2000
Creator: REED,ALFRED W.
System: The UNT Digital Library
Flowing Interval Spacing Parameter for Matrix Diffusion in the Saturated Zone (open access)

Flowing Interval Spacing Parameter for Matrix Diffusion in the Saturated Zone

None
Date: November 9, 2000
Creator: Kuzio, Stephanie P.; Arnold, Bill W. & Gauthier, John H.
System: The UNT Digital Library
Modeling Thermal Desaturation of Fracture Porous Rocks (open access)

Modeling Thermal Desaturation of Fracture Porous Rocks

None
Date: November 9, 2000
Creator: REED,ALFRED W.
System: The UNT Digital Library
Parallel Smoothed Aggregation Multigrid: Aggregation Strategies on Massively Parallel Machines (open access)

Parallel Smoothed Aggregation Multigrid: Aggregation Strategies on Massively Parallel Machines

Algebraic multigrid methods offer the hope that multigrid convergence can be achieved (for at least some important applications) without a great deal of effort from engineers and scientists wishing to solve linear systems. In this paper the authors consider parallelization of the smoothed aggregation multi-grid method. Smoothed aggregation is one of the most promising algebraic multigrid methods. Therefore, developing parallel variants with both good convergence and efficiency properties is of great importance. However, parallelization is nontrivial due to the somewhat sequential aggregation (or grid coarsening) phase. In this paper, they discuss three different parallel aggregation algorithms and illustrate the advantages and disadvantages of each variant in terms of parallelism and convergence. Numerical results will be shown on the Intel Teraflop computer for some large problems coming from nontrivial codes: quasi-static electric potential simulation and a fluid flow calculation.
Date: November 9, 2000
Creator: Tuminaro, Ray S.
System: The UNT Digital Library
A possible hadronic excess in psi(2S) decay and the rho pi puzzle (open access)

A possible hadronic excess in psi(2S) decay and the rho pi puzzle

We study the so-called {rho}{pi} puzzle of the {psi}(2S) decay by incorporating two inputs; the relative phase between the one-photon and the gluonic decay amplitude, and a possible hadronic excess in the inclusive nonelectromagnetic decay rate of {psi}(2S). We look into the possibility that the hadronic excess in {psi}(2S) originates from a decay process of long-distance origin which is absent from the J/{upsilon} decay. We propose that the amplitude of this additional process happens to nearly cancel the short-distance gluonic amplitude in the exclusive decay {psi}(2S) {yields} 1{sup -}0{sup -} and turn the sum dominantly real in contrast to the J/{psi} decay. We present general consequences of this mechanism and survey two models which might possibly explain the source of this additional amplitude.
Date: November 9, 2000
Creator: Suzuki, Mahiko
System: The UNT Digital Library
Biomass Power and State Renewable Energy Policies Under Electric Industry Restructuring (open access)

Biomass Power and State Renewable Energy Policies Under Electric Industry Restructuring

The paper discusses policies that foster renewable energy as enacted by states in response to utility restructuring. In particular, it discusses the role of biomass in these policies.
Date: October 9, 2000
Creator: Porter, K. & Wiser, R.
System: The UNT Digital Library
Digitally Marking RSA Moduli (open access)

Digitally Marking RSA Moduli

The moduli used in RSA (see [5]) can be generated by many different sources. The generator of that modulus (assuming a single entity generates the modulus) knows its factorization. They would have the ability to forge signatures or break any system based on this moduli. If a moduli and the RSA parameters associated with it were generated by a reputable source, the system would have higher value than if the parameters were generated by an unknown entity. So for tracking, security, confidence and financial reasons it would be beneficial to know who the generator of the RSA modulus was. This is where digital marking comes in. An RSA modulus ia digitally marked, or digitally trade marked, if the generator and other identifying features of the modulus (such as its intended user, the version number, etc.) can be identified and possibly verified by the modulus itself. The basic concept of digitally marking an RSA modulus would be to fix the upper bits of the modulus to this tag. Thus anyone who sees the public modulus can tell who generated the modulus and who the generator believes the intended user/owner of the modulus is.
Date: October 9, 2000
Creator: Johnston, A. M.
System: The UNT Digital Library
The Dynamic Competition Between Stress Generation and Relaxation Mechanisms During Coalescence of Volmer-Weber Thin Films (open access)

The Dynamic Competition Between Stress Generation and Relaxation Mechanisms During Coalescence of Volmer-Weber Thin Films

None
Date: October 9, 2000
Creator: Floro, J. A.; Hearne, S. J.; Hunter, J. A.; Kotula, P. G.; Chason, E.; Seel, S. C. et al.
System: The UNT Digital Library
Experience of Russian Radiochemical Plant Sites With the Bubbler Probe Manometry Tank Volume Measurement System. (open access)

Experience of Russian Radiochemical Plant Sites With the Bubbler Probe Manometry Tank Volume Measurement System.

None
Date: October 9, 2000
Creator: Suda, S.; Zuhoski, P.; Fishbone, L. G.; Darenskikh, O.; Purygin, V. & Golosovsky, A.
System: The UNT Digital Library
Experimental Testbed for the Study of Hydrodynamic Issues in Supernovae (open access)

Experimental Testbed for the Study of Hydrodynamic Issues in Supernovae

More than a decade after the explosion of SN 1987A, unresolved discrepancies still remain in attempts to numerically simulate the mixing processes initiated by the passage of a very strong shock through the layered structure of the progenitor star. Numerically computed velocities of the radioactive {sup 56}Ni and {sup 56}CO, produced by shock-induced explosive burning within the silicon layer for example, are still more than 50% too low as compared with the measured velocities. In order to resolve such discrepancies between observation and simulation, an experimental testbed has been designed on the Omega Laser for the study of hydrodynamic issues of importance to supernovae (SNe). In this paper, we present results from a series of scaled laboratory experiments designed to isolate and explore several issues in the hydrodynamics of SN explosions. The results of the experiments are compared with numerical simulations and are generally found to be in reasonable agreement.
Date: October 9, 2000
Creator: Robey, H. F.; Kane, J. O.; Remington, B. A.; Drake, R. P.; Hurricane, O. A.; Louis, H. et al.
System: The UNT Digital Library
Gas Phase Chemical Detection with an Integrated Chemical Analysis System (open access)

Gas Phase Chemical Detection with an Integrated Chemical Analysis System

None
Date: October 9, 2000
Creator: Casalnuovo, S. A.; Frye-Mason, G. C.; Kottenstette, R.; Heller, E. J.; Matzke, C. M.; Lewis, P. R. et al.
System: The UNT Digital Library
Multiparticle Production at Rhic and Lhc: A Classical Point of View. (open access)

Multiparticle Production at Rhic and Lhc: A Classical Point of View.

We report results of our ongoing nonperturbative numerical study of a classical effective theory describing low-x partons in the central region of a heavy-ion collision. In particular, we give estimates of the initial transverse energies and multiplicities for a wide range of collision regimes, including those at RHIC and at LHC.
Date: October 9, 2000
Creator: Krasnitz, A. & VENUGOPALAN, R.
System: The UNT Digital Library
National Needs Drivers for Nanotechnology (open access)

National Needs Drivers for Nanotechnology

Societal needs related to demographics, resources, and human behavior will drive technological advances over the next 20 years. Nanotechnology is anticipated to be an important enabler of these advances, and thus maybe anticipated to have significant influence on new systems approaches to solving societal problems as well as on extending current science and technology-based applications. To examine the potential implications of nanotechnology a societal needs-driven approach is taken. Thus the methodology is to present the definition of the problem, and then examine system concepts, technology issues, and promising future directions. We approach the problem definition from a national and global security perspective and identify three key areas involving the condition of the planet, the human condition, and global security. In anticipating societal issues in the context of revolutionary technologies, such as maybe enabled by nanoscience, the importance of working on the entire life cycle of any technological solution is stressed.
Date: October 9, 2000
Creator: Yonas, G. & Picraux, S.T.
System: The UNT Digital Library
Rare K+ Decays from Experiment E787 (open access)

Rare K+ Decays from Experiment E787

This paper presents the latest results from experiment E787, at Brookhaven National Laboratory, on K{sup +} {r_arrow} {pi}{sup +} {nu}{bar {nu}} and radiative K{sup +} decays. The result for K{sup +} {r_arrow} {pi}{sup +} {nu}{bar {nu}} uses data collected in runs taken during 1995, 1996 and 1997. In addition, they discuss plans for future measurements of K{sup +} {r_arrow} {pi}{sup +} {nu}{bar {nu}}.
Date: October 9, 2000
Creator: Jain, V.
System: The UNT Digital Library
Superconductivity in the Polymeric Phase of Na2CsC60 (open access)

Superconductivity in the Polymeric Phase of Na2CsC60

None
Date: October 9, 2000
Creator: Schirber, J. E.; Morosin, B.; Kwei, G. H.; Yildirim, T.; Fischer, J. E. & Jorgensen, J. D.
System: The UNT Digital Library
DD Neutron Yield Measurements on Z Using Lead Probes (open access)

DD Neutron Yield Measurements on Z Using Lead Probes

A series of inertial confinement fusion (ICF) capsule experiments were run on the Z machine at Sandia's Pulsed Power directorate. These experiments were designed specifically to implode a 2 mm diameter hollow plastic capsule filled with deuterium gas. The implosion of the capsule should raise the temperature (kinetic energy) of the deuterium gas ions, which will interact with each other and produce 2.45 MeV fusion neutrons. The author is reporting on one diagnostic technique used to measure the yield of these fusion neutrons. The technique chosen to measure the DD neutron yield is the use of lead (Pb) probe detectors. The assignment was to calibrate two detectors for the 2.50-MeV neutrons produced by the deuterium-deuterium fusion reactions on Z. The author introduces ICF, and then describes the theory, the design, and the calibration of the lead probe. Finally, she presents the results of the ICF experiments and explain the difficulties inherent in analyzing the data.
Date: August 9, 2000
Creator: GERKEN,ERICA S.
System: The UNT Digital Library
Development of a Programming Adapter for a Classified-Data Processor Device (open access)

Development of a Programming Adapter for a Classified-Data Processor Device

This summer, the author was tasked with the development of a design and prototype for a Programming Adapter (PA). This device must interface to a specialized cluster of computers at a US Air Force programming station. The PA is a command/response system capable of recognizing commands from a host Programming Computer (PC) generating a response to these commands according to design requirements. The PA must also route classified serial data between a programming station and any target devices on the PA without compromising the data. In this manner, classified data can pass through the adapter, but when data transfer is complete, the PA can be handled as an unclassified piece of hardware.
Date: August 9, 2000
Creator: Perea, Dominic A.
System: The UNT Digital Library
Microfabrication and Micropatterning with Soft Lithography (open access)

Microfabrication and Micropatterning with Soft Lithography

None
Date: August 9, 2000
Creator: Baca, Justin T. & Myers, Ramona L.
System: The UNT Digital Library
Miniaturized Domain Engineered Multilayer Actuators (open access)

Miniaturized Domain Engineered Multilayer Actuators

None
Date: August 9, 2000
Creator: Tuttle, Bruce A.; Yang, Pin; Bourbina, Matthew F.; Venturini, Eugene L.; Nicolaysen, Scott D.; Olson, Walter R. et al.
System: The UNT Digital Library