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Adhesive Bonding of Polymeric Materials for Automotive Applications (open access)

Adhesive Bonding of Polymeric Materials for Automotive Applications

In 1992, the Oak Ridge National Laboratory (ORNL) began a cooperative research program with the Automotive Composites Consortium (ACC) to develop technologies that would overcome obstacles to the adhesive bonding of current and future automotive materials. This effort is part of a larger Department of Energy (DOE) program to promote the use of lighter weight materials in automotive structures. By reducing the weight of current automobiles, greater fuel economy and reduced emissions can be achieved. The bonding of similar and dissimilar materials was identified as being of primary importance since this enabling technology gives designers the freedom to choose from an expanded menu of low-mass materials for structural component weight reduction. Early in the project`s conception, five key areas were identified as being of primary importance to the automotive industry.
Date: November 18, 1994
Creator: Warren, C.D., Boeman, R.G., Paulauskas, F.L.
System: The UNT Digital Library
Development of subcontractor indirect cost and other direct cost at the DOE Fernald Site (open access)

Development of subcontractor indirect cost and other direct cost at the DOE Fernald Site

The Fernald Environmental Restoration Management Corporation (FERMCO) took great strides in the development of cost estimates at Fernald. There have been many opportunities to improve on how the policies and procedures pertaining to cost estimates were to be implemented. As FERMCO took over the existing Fernald facility, the Project Controls Division began to format the estimating procedures and tools to do business at Fernald. The Estimating Department looked at the problems that pre-existed at the site. One of the key problems that FERMCO encountered was how to summarized the direct and indirect accounts of each subcontracted estimate. Direct costs were broken down by prime and sub-prime accounts. This presented a level of detail that had not been experienced at the site before; it also created many issues concerning accounts and definitions to be applied to ``all other accounts associated with a project.`` Existing subcontract indirect cost accounts were reviewed from existing historical estimates. It was found that some were very detailed and some were not. The Estimating Department was given the task of standardizing the accounts and percentages for each of the subcontractor indirect costs. Then, as the project progressed, the percentages could be revised with actual estimates, subcontract comparisons, …
Date: November 18, 1994
Creator: Cossman, R. L.
System: The UNT Digital Library
Detection of concealed mercury with thermal neutrons (open access)

Detection of concealed mercury with thermal neutrons

In the United States today, governments at all levels and the citizenry are paying increasing attention to the effects, both real and hypothetical, of industrial activity on the environment. Responsible modem industries, reflecting this heightened public and regulatory awareness, are either substituting benign materials for hazardous ones, or using hazardous materials only under carefully controlled conditions. In addition, present-day environmental consciousness dictates that we deal responsibly with legacy wastes. The decontamination and decommissioning (D&D) of facilities at which mercury was used or processed presents a variety of challenges. Elemental mercury is a liquid at room temperature and readily evaporates in air. In large mercury-laden buildings, droplets may evaporate from one area only to recondense in other cooler areas. The rate of evaporation is a function of humidity and temperature; consequently, different parts of a building may be sources or sinks of mercury at different times of the day or even the year. Additionally, although mercury oxidizes in air, the oxides decompose upon heating. Hence, oxides contained within pipes or equipment, may be decomposed when those pipes and equipment are cut with saws or torches. Furthermore, mercury seeps through the pores and cracks in concrete blocks and pads, and collects as …
Date: August 18, 1994
Creator: Bell, Z.W.
System: The UNT Digital Library
EGS4 in `94: A decade of enhancements (open access)

EGS4 in `94: A decade of enhancements

This paper presents an overview of the developments made to the EGS4 code over the past decade. This code is a Monte Carlo code developed to study electron-photon transport properties. It is widely used, in particular in the medical physics field, it has been updated, expanded, benchmarked, and applied to a wide array of problems. The paper covers precursors to this code, a basic snapshop of its physics and calculation methods, and an overview of how it has been expanded during the past decade.
Date: August 18, 1994
Creator: Nelson, W. R.; Bielajew, A. F.; Rogers, D. W. O. & Hirayama, H.
System: The UNT Digital Library
A mixed time integration method for large scale acoustic fluid-structure interaction (open access)

A mixed time integration method for large scale acoustic fluid-structure interaction

The transient, coupled, interaction of sound with structures is a process in which an acoustic fluid surrounding an elastic body contributes to the effective inertia and elasticity of the body. Conversely, the presence of an elastic body in an acoustic medium influences the behavior of propagating disturbances. This paper details the application of a mixed explicit-implicit time integration algorithm to the fully coupled acoustic fluidstructure interaction problem. Based upon a dispersion analysis of the semi-discrete wave equation a second-order, explicit scheme for solving the wave equation is developed. The combination of a highly vectorized, explicit, acoustic fluid solver with an implicit structural code for linear elastodynamics has resulted in a simulation tool, PING, for acoustic fluid-structure interaction. PING`s execution rates range from 1{mu}s/Element/{delta}t for rigid scattering to 10{mu}s/Element/{delta}t for fully coupled problems. Several examples of PING`s application to 3-D problems serve in part to validate the code, and also to demonstrate the capability to treat complex geometry, acoustic fluid-structure problems which require high resolution meshes.
Date: July 18, 1994
Creator: Christon, M. A.; Wineman, S. J.; Goudreau, G. L. & Foch, J. D.
System: The UNT Digital Library
Preliminary studies to determine the shelf life of HEPA filters (open access)

Preliminary studies to determine the shelf life of HEPA filters

We have completed a preliminary study using filter media tests and filter qualification tests to investigate the effect of shelf-life on HEPA filter performance. Our media studies showed that the tensile strength decreased with age, but the data were not sufficient to establish a shelf-life. Thermogravimetric analyses demonstrated that one manufacturer had media with low tensile strength due to insufficient binder. The filter qualification tests (heated air and overpressure) conducted on different aged filters showed that filter age is not the primary factor affecting filter performance; materials and the construction design have a greater effect. An unexpected finding of our study was that sub-standard HEPA filters have been installed in DOE facilities despite existing regulations and filter qualification tests. We found that the filter with low tensile strength failed the overpressure test. The same filter had passed the heated air test, but left the filter so structurally weak, it was prone to blowout. We recommend that DOE initiate a filter qualification program to prevent this occurrence.
Date: July 18, 1994
Creator: Gilbert, H.; Fretthold, J. K.; Rainer, F.; Bergman, W. & Beason, D.
System: The UNT Digital Library
A tau-charm-factory at Argonne (open access)

A tau-charm-factory at Argonne

In this paper we explore the possibility of building a tau-charm-factory at the Argonne National Laboratory. A tau-charm-factory is an e{sup +}e{sup {minus}} collider with a center-of-mass energy between 3.0 GeV and 5.0 GeV and a luminosity of at least 1 {times} 10{sup 33}cm{sup {minus}2}s{sup {minus}1}. Once operational, the facility will produce large samples of {tau} pairs, charm mesons, and charmonium with either negligible or well understood backgrounds. This will lead to high precision measurements in the second generation quark and the third generation lepton sectors that cannot be done at other facilities. Basic physical properties and processes, such as the tau neutrino mass, rare tau decays, charm decay constants, rare charm meson decays, neutral D{sup 0} -- meson mixing, and many more will be studied with unique precision. An initial design of the collider including the injector system is described. The design shows that a luminosity of at least 1 {times} 10{sup 33}cm{sup {minus}2}s{sup {minus}1} can be achieved over the entire center-of-mass energy range of the factory.
Date: July 18, 1994
Creator: Norem, J. & Repond, J.
System: The UNT Digital Library
The superconducting magnet system for the Tokamak Physics Experiment (open access)

The superconducting magnet system for the Tokamak Physics Experiment

The superconducting magnet system for the Tokamak Physics experiment (TPX) will be the first all superconducting magnet system for a Tokamak, where the poloidal field coils, in addition to the toroidal field coils are superconducting. The magnet system is designed to operate in a steady state mode, and to initiate the plasma discharge ohmically. The toroidal field system provides a peak field of 4.0 Tesla on the plasma axis at a plasma major radius of 2.25 m. The peak field on the niobium 3-tin, cable-in-conduit (CIC) conductor is 8.4 Tesla for the 16 toroidal field coils. The toroidal field coils must absorb approximately 5 kW due to nuclear heating, eddy currents, and other sources. The poloidal field system provides a total of 18 volt seconds to initiate the plasma and drive a plasma current up to 2 MA. The poloidal field system consists of 14 individual coils which are arranged symmetrically above and below the horizontal mid plane. Four pairs of coils make up the central solenoid, and three paris of poloidal ring coils complete the system. The poloidal field coils all use a cable-in-conduit conductor, using either niobium 3-tin (NB{sub 3}Sn) or niobium titanium (NbTi) superconducting strands depending on …
Date: June 18, 1994
Creator: Lang, D. D.; Bulmer, R. J. & Chaplin, M. R.
System: The UNT Digital Library
Lithological and rheological constraints on fault rupture scenarios for ground motion hazard prediction (open access)

Lithological and rheological constraints on fault rupture scenarios for ground motion hazard prediction

This paper tests an approach to predict the range of ground motion hazard at specific sites generated by earthquakes on specific faults. The approach is based upon structural, lithological and rheological descriptions of the fault zones, development of fault rupture scenarios, and computation of synthetic seismograms using empirical Green`s functions. Faults are placed within a regional geomechanical model. The approach is based upon three hypothesis: (1) An exact solution of the representation relation that utilizes empirical Green`s functions enables very accurate computation of ground motions generated by a given rupture; (2) a general description of the rupture is sufficient; and (3) the structural, lithological and Theological characteristics of a fault can be used to constrain, in advance, possible future rupture histories. Ground motion hazard here refers to three-component, full wave train descriptions of displacement, velocity, and acceleration over the frequency band 0.01 to 25 Hz. Corollaries to these hypotheses are that the range of possible fault rupture histories is narrow enough to functionally constrain the range of strong ground motion predictions, and that a discreet set of rupture histories is sufficient to span the infinite combinations possible from a given range of rupture parameters.
Date: April 18, 1994
Creator: Hutchings, L. & Foxall, W.
System: The UNT Digital Library
Coupling correction using closed orbit measurements (open access)

Coupling correction using closed orbit measurements

The authors describe a coupling correction scheme they have developed and used to successfully reduce the vertical emittance of the NSLS X-Ray ring by a factor of 6 to below 2 A. This gives a vertical to horizontal emittance ratio of less than 0.2%. They find the strengths of 17 skew quadrupoles to simultaneously minimize the vertical dispersion and the coupling. As a measure of coupling they utilize the shift in vertical closed orbit resulting from a change in strength of a horizontal steering magnet. Experimental measurements confirm the reduced emittance.
Date: February 18, 1994
Creator: Safranek, J. & Krinsky, S.
System: The UNT Digital Library
Stapp`S Quantum Dualism: The James/Heisenberg Model of Consciousness (open access)

Stapp`S Quantum Dualism: The James/Heisenberg Model of Consciousness

Henry Stapp attempts to resolve the Cartesian dilemma by introducing what the author would characterize as an ontological dualism between mind and matter. His model for mind comes from William James` description of conscious events and for matter from Werner Heisenberg`s ontological model for quantum events (wave function collapse). His demonstration of the isomorphism between the two types of events is successful, but in the author`s opinion fails to establish a monistic, scientific theory. The author traces Stapp`s failure to his adamant rejection of arbitrariness, or `randomness`. This makes it impossible for him (or for Bohr and Pauli before him) to understand the power of Darwin`s explanation of biology, let along the triumphs of modern `neo-Darwinism`. The author notes that the point at issue is a modern version of the unresolved opposition between Leucippus and Democritus on one side and Epicurus on the other. Stapp`s views are contrasted with recent discussions of consciousness by two eminent biologists: Crick and Edelman. They locate the problem firmly in the context of natural selection on the surface of the earth. Their approaches provide a sound basis for further scientific work. The author briefly examines the connection between this scientific (rather than ontological) framework …
Date: February 18, 1994
Creator: Noyes, H. P.
System: The UNT Digital Library
Experimental evidence for lattice effects in high temperature superconductors (open access)

Experimental evidence for lattice effects in high temperature superconductors

We present an overview of the experimental evidence for a role of the lattice in the mechanism of high temperature superconductivity. It appears unlikely that a solely conventional electron-phonon interaction produces the pairing. However, there is ample evidence of strong electron and spin to lattice coupling and observations of a response of the lattice to the electronic state. We draw attention to the importance of the local structure in discussions of lattice effects in high-{Tc} superconductivity.
Date: January 18, 1994
Creator: Billinge, S. J. L.; Kwei, G. H. & Thompson, J. D.
System: The UNT Digital Library