Many regulated entities today charge that environmental regulations have become inefficient and could be made more cost effective. The US Environmental Protection Agency (EPA) has identified several initiatives to help ''reinvent'' environmental regulations and address those charges. At the same time, the President and others are pursuing the development and use of new environmental technologies. Reflecting these trends, Argonne National Laboratory is helping develop a prototype multimedia environmental regulatory program for petroleum refineries operating in the Mure. The project differs from other regulatory reinvention efforts in that it is Mure-oriented and, as a result, may result in recommendations that depart significantly from those from existing regulatory systems. This paper notes the importance of communicating environmental information when developing and implementing regulatory approaches. Two approaches--one goal-based and the other risk-based--are being considered for the prototype regulatory program. Both are site-specific, and the implementation of both requires a significant amount of communication among refiners, regulators, and other stakeholders. Of even greater importance, however, is the communication involved in the development of these approaches. Because these new regulatory approaches could fundamentally change the way regulated entities operate, ideas and concerns of groups likely to be affected by the regulatory prototypes need to be …

The Advanced Photon Source at Argonne National Laboratory has implemented a number of methods for people to interact with the accelerator systems. The accelerator operators use Sun workstations running MEDM and WCL to interface interactively with the accelerator, however, many people need to view information rather than interact with the machine. One of the most common interfaces for viewing information at the Advanced Photon Source is the World Wide Web. Information such as operations logbook entries, machine status updates, and displays of archived and current data are easily available to APS personnel. This interface between people and the accelerator has proven to be quite useful. Because the Intranet is operating-system independent and inherently unidirectional, ensuring the prevention of unauthorized or accidental control of the accelerators is straightforward.

The availability of complete emissions and entrainment data, topographic data and statistical meteorology data, and the modeling to account for all aerosol constituents presently found in our atmospheres, is not likely to improve substantially in the foreseeable future. This inability to model all of the transformation and transport processes which result in visibility-impairing aerosol species arriving at a point of interest, does not necessarily prevent our assessment of the benefits of reducing emissions from sources that can be modeled. We must, however, have an adequate statistical record of the concentrations of these materials and we must have a reliable means to apportion the concentration into controllable (i.e., those we can quantify and model) and uncontrollable fractions. Statistical concentration data, for remote scenic regions, are available for relevant aerosol species from the IMPROVE Network, for years beginning in 1988. A comparable network is unfortunately not available for urban areas. Here we describe the evolution of our source apportionment assumptions for two remote sites of much current interest, Grand Canyon and Shenandoah National Parks. Ingenuity and in some cases additional field investigations are necessary to improve such apportionment assumptions. To that end we briefly summarize promising approaches, such as receptor analysis and …

We have studied magnetic field penetration and vortex line formation in a [Nb(100 {angstrom})/Si(15 {angstrom})]x20 multilayer by magnetization and polarized neutron reflection. With the magnetic field applied parallel to the surface, the magnetization revealed the presence of a kink above H{sub cl} indicative of transitions between one row of fluxoids and two rows of fluxoids parallel to the surface. The spin-dependence of neutron reflectivity below H{sub cl} was consistent with a penetration depth of 1200 {angstrom}, substantially larger than that of bulk Nb. In the mixed phase (H{sub ext} > H{sub cl}) the field was found to penetrate the surface, with a slope as found in the case of H{sub ext} < H{sub cl}. At H{sub ext} > H{sub cl} vortex forms in addition to surface penetration. A modulation of the vortex fields was found with the periodicity of the Nb/Si bilayers as evidenced by the spin dependence of the reflectivity at the first Bragg peak of the multilayer.

Depletion calculations have been performed for the McClellan reactor history from January 1990 through August 1996. A database has been generated for continuing use by operations personnel which contains the isotopic inventory for all fuel elements and fuel-followed control rods maintained at McClellan. The calculations are based on the three-dimensional diffusion theory code REBUS-3 which is available through the Radiation Safety Information Computational Center (RSICC). Burnup-dependent cross-sections were developed at zero power temperatures and full power temperatures using the WIMS code (also available through RSICC). WIMS is based on discretized transport theory to calculate the neutron flux as a function of energy and position in a one-dimensional cell. Based on the initial depletion calculations, a method was developed to allow operations personnel to perform depletion calculations and update the database with a minimal amount of effort. Depletion estimates and calculations can be performed by simply entering the core loading configuration, the position of the control rods at the start and end of cycle, the reactor power level, the duration of the reactor cycle, and the time since the last reactor cycle. The depletion and buildup of isotopes of interest (heavy metal isotopes, erbium isotopes, and fission product poisons) are calculated …

In this paper, we review some of the work our group has done in the past few years to obtain the electron self-energy of high temperature superconductors by analysis of angle-resolved photoemission data. We focus on three examples which have revealed: (1) a d-wave superconducting gap, (2) a collective mode in the superconducting state, and (3) pairing correlations in the pseudogap phase. In each case, although a novel result is obtained which captures the essence of the data, the conventional physics used leads to an incomplete picture. This indicates that new physics needs to be developed to obtain a proper understanding of these materials.

Current techniques for assessing the benefits of certain anthropogenic emission reductions are largely influenced by limitations in emissions data and atmospheric modeling capability and by the highly variant nature of meteorology. These data and modeling limitations are likely to continue for the foreseeable future, during which time important strategic decisions need to be made. Statistical atmospheric quality data and apportionment techniques are used in Monte-Carlo models to offset serious shortfalls in emissions, entrainment, topography, statistical meteorology data and atmospheric modeling. This paper describes the evolution of Department of Energy (DOE) Monte-Carlo based assessment models and the development of statistical inputs. A companion paper describes techniques which are used to develop the apportionment factors used in the assessment models.

Ceramic matrix composites are being developed for numerous high temperature applications, including rotors and combustors for advanced turbine engines, heat exchanger and hot-gas filters for coal gasification plants. Among the materials of interest are silicon-carbide-fiber-reinforced-silicon-carbide (SiC{sub (f)}/SiC), silicon-carbide-fiber-reinforced-silicon-nitride (SiC{sub (f)}/Si{sub 3}N{sub 4}), aluminum-oxide-reinforced-alumina (Al{sub 2}O{sub 3(f)}/Al{sub 2}O{sub 3}), etc. In the manufacturing of these ceramic composites, the conditions of the fiber/matrix interface are critical to the mechanical and thermal behavior of the component. Defects such as delaminations and non-uniform porosity can directly effect the performance. A nondestructive evaluation (NDE) method, developed at Argonne National Laboratory has proved beneficial in analyzing as-processed conditions and defect detection created during manufacturing. This NDE method uses infrared thermal imaging for fill-field quantitative measurement of the distribution of thermal diffusivity in large components. Intensity transform algorithms have been used for contrast enhancement of the output image. Nonuniformity correction and automatic gain control are used to dynamically optimize video contrast and brightness, providing additional resolution in the acquired images. Digital filtering, interpolation, and least-squares-estimation techniques have been incorporated for noise reduction and data acquisition. The Argonne NDE system has been utilized to determine thermal shock damage, density variations, and variations in fiber coating in a full …

Glass-bonded zeolite is being considered as a candidate ceramic waste form for storing radioactive isotopes separated from spent nuclear fuel in the electrorefining process. To determine the stability of glass-bonded zeolite under irradiation, transmission electron microscope samples were irradiated using high energy helium, lead, and krypton. The major crystalline phase of the waste form, which retains alkaline and alkaline earth fission products, loses its long range order under both helium and krypton irradiation. The dose at which the long range crystalline structure is lost is about 0.4 dpa for helium and 0.1 dpa for krypton. Because the damage from lead is localized in such a small region of the sample, damage could not be recognized even at a peak damage of 50 dpa. Because the crystalline phase loses its long range structure due to irradiation, the effect on retention capacity needs to be further evaluated.

Innovative, cost-effective technologies that have a positive life-cycle environmental impact and yield marketable products are needed to meet the challenges of the recycling industry. Four materials-recovery technologies that are being developed at Argonne National Laboratory in cooperation with industrial partners are described in this paper: (1) dezincing of galvanized steel scrap; (2) material recovery from auto-shredder residue; (3) high-value-plastics recovery from obsolete appliances; and (4) aluminum salt cake recycling. These technologies are expected to be applicable to the production of low-cost, high-quality raw materials from a wide range of waste streams.

Mixed-conducting ceramic oxides have potential uses in high-temperature electrochemical applications such as solid oxide fuel cells, batteries, sensors, and oxygen-permeable membranes. The Sr-Fe-Co-O system combines high electronic/ionic conductivity with appreciable oxygen permeability at elevated temperatures. Dense ceramic membranes made of this material can be used to separate high-purity oxygen from air without the need for external electrical circuitry, or to partially oxidize methane to produce syngas. Samples of Sr{sub 2}Fe{sub 3{minus}x}Co{sub x}O{sub y} (with x = 0, 0.6, 1.0, and 1.4) were prepared by solid-state reaction method in atmospheres with various oxygen partial pressures (pO{sub 2}) and were characterized by X-ray diffraction, scanning electron microscopy, and electrical conductivity testing. Phase components of the sample are dependent on cobalt concentration and pO{sub 2}. Electrical conductivity increases with increasing temperature and cobalt content in the material.

We describe the use of automatic differentiation (AD) to enhance a compressible Navier-Stokes model. With the solver, AD is used to accelerate convergence by more than an order of magnitude. Outside the solver, AD is used to compute the derivatives needed for optimization. We emphasize the potential for performance gains if the programmer does not treat AD as a black box, but instead utilizes high-level knowledge about the nature of the application.

Given the events of the past 25 years concerning energy and environmental issues and our reaction to them, what lessons can we learn? First, the individual American consumer wants and expects energy to be a stable commodity with low prices and easy availability. As evidenced by the heated debate over increasing the federal gasoline tax by $.05 per gallon (which would still leave Americans paying only one-third of what Europeans pay for gasoline), increases in energy prices elicit very strong public and political opposition. As further evidence, it has been argued that the general public support of the Gulf War was due, in part, to a recognition of the need to maintain a stable source of cheap oil from the region. The American public wants to maintain the benefits of cheap and abundant energy and expects its political leaders to make it happen. A second lesson is that if constraints on the energy supply do occur (e.g., the OPEC-imposed oil embargo) ardor environmental impacts from energy use do appear to be significant (e.g., SO{sub 2} and CO{sub 2} emissions), the preference is for a technology fix rather than a behavioral change. This is evidenced by our reliance on moving low-sulfur …

In 1995, the American Association of Physicists in Medicine Task Group 43 (AAPM TG-43) published a protocol obsoleting all mixed-field radiation dosimetry for Cf-252. Recommendations for a new brachytherapy dosimetry formalism made by this Task Group favor quantification of source strength in terms of air kerma rather than apparent Curies or other radiation units. Additionally, representation of this dosimetry data in terms of radial dose functions, anisotropy functions, geometric factors, and dose rate constants are in an angular and radial (spherical) coordinate system as recommended, rather than the along-away dosimetry data (Cartesian coordinate system) currently available. This paper presents the initial results of calculated neutron dosimetry in a water phantom for a Cf-252 applicator tube (AT) type medical source soon available from Oak Ridge National Laboratory (ORNL).

The Californium User Facility (CUF) for Neutron Science has been established to provide {sup 252}Cf-based neutron irradiation services and research capabilities including neutron activation analysis (NAA). A major advantage of the CUF is its accessibility and controlled experimental conditions compared with those of a reactor environment The CUF maintains the world`s largest inventory of compact {sup 252}Cf neutron sources. Neutron source intensities of {le} 10{sup 11} neutrons/s are available for irradiations within a contamination-free hot cell, capable of providing thermal and fast neutron fluxes exceeding 10{sup 8} cm{sup {minus}2} s{sup {minus}1} at the sample. Total flux of {ge}10{sup 9} cm{sup {minus}2} s{sup {minus}1} is feasible for large-volume irradiation rabbits within the {sup 252}Cf storage pool. Neutron and gamma transport calculations have been performed using the Monte Carlo transport code MCNP to estimate irradiation fluxes available for sample activation within the hot cell and storage pool and to design and optimize a prompt gamma NAA (PGNAA) configuration for large sample volumes. Confirmatory NAA irradiations have been performed within the pool. Gamma spectroscopy capabilities including PGNAA are being established within the CUF for sample analysis.

We have measured the optical constants of montmorillonite and the separated coats and cores of B. subtilis spores over the wavelength interval from 200 nm to 2500 nm. The optical constants of kaolin were obtained over the wavelength interval from 130 nm to 2500 nm. Our results are applicable to the development of systems for detection of airborne biological contaminants. Future work will include measurement of the optical constants of B. cereus spores, B. sub tilts vegetative cells, egg albumin, illite, and a mixture (by weight) of one third kaolin, one third montmorillonite, and one third illite.

Rigid polyurethane foams are frequently used as encapsulants to isolate and support thermally sensitive components within weapon systems. When exposed to abnormal thermal environments, such as fire, the polyurethane foam decomposes to form products having a wide distribution of molecular weights and can dominate the overall thermal response of the system. Mechanical response of the decomposing foam, such as thermal expansion under various loading conditions created by gas generation, remains a major unsolved problem. A constitutive model of the reactive foam is needed to describe the coupling between mechanical response and chemical decomposition of foam exposed to environments such as fire. Towards this end, a reactive elastic-plastic constitutive model based on bubble mechanics describing nucleation, decomposition chemistry, and elastic/plastic mechanical behavior of rigid polyurethane foam has been developed. A local force balance, with mass continuity constraints, forms the basis of the constitutive model requiring input of temperature and the fraction of the material converted to gas. This constitutive model provides a stress-strain relationship which is applicable for a broad class of reacting materials such as explosives, propellants, pyrotechnics, and decomposing foams. The model is applied to a block of foam exposed to various thermal fluxes. The model is also applied …

This paper, an update of papers presented in 1984 and 1995, describes the large number and diverse variety of EMP simulators that exist outside the US. The end of the Cold War has provided the opportunity to learn of new simulators and to compare their characteristics as well as the test methods employed in them. While similarities exist with EMP simulators developed in the US and other western countries, in some cases the simulators developed by researchers of the former Soviet Union and other Warsaw Pact nations provide some very interesting differences in approach. As is the case with US EMP simulators, no one perfect EMP simulator exists. Baum has classified non-source region EMP simulators in three categories: (1) guided wave, (2) dipole, and (3) hybrid. This paper describes several examples that fall into these three categories as well as a unique source region simulator in Russia that does not. All designs have inherent limitations; thus the large variety that exists. Some analysis and extrapolation of results must always be done. The ideal of a simple zap test to prove a system hard to EMP is just that--an unachievable ideal.

The engineering process of integrating the Petawatt (10{sup 15} watts) laser system into the existing 30 kJ (UV) Nova laser at Lawrence Livermore National Laboratory (LLNL) is described in detail. The nanosecond-long, chirped Petawatt laser pulse is initially generated in a separate master oscillator room and then injected into one of Nova`s 10 beamlines. There, the pulse is further amplified and enlarged to {approximately}{phi}60 cm, temporally compressed under vacuum to <500 fs using large diameter diffraction gratings, and then finally focused onto targets using a parabolic mirror. The major Petawatt components are physically large which created many significant engineering challenges in design, installation and implementation. These include the diffraction gratings and mirrors, vacuum compressor chamber, target chamber, and parabolic focusing mirror. Other Petawatt system components were also technically challenging and include: an injection beamline, transport spatial filters, laser diagnostics, alignment components, motor controls, interlocks, timing and synchronization systems, support structures, and vacuum systems. The entire Petawatt laser system was designed, fabricated, installed, and activated while the Nova laser continued its normal two-shift operation. This process required careful engineering and detailed planning to prevent experimental downtime and to complete the project on schedule.

Antiproton production in heavy ion collisions reflects subtle interplay between initial production and absorption by nucleons. Because the AGS energies (10--20 A{center_dot}GeV/c) are close to the antiproton production threshold, antiproton may be sensitive to cooperative processes such as QGP and hadronic multi-step processes. On the other hand, antiproton has been proposed as a probe of baryon density due to large N{anti N} annihilation cross sections. Cascade models predict the maximum baryon density reaches about 10 times the normal nucleus density in central Au+Au collisions, where the strong antiproton absorption is expected. In this paper, the authors show systematic studies of antiproton production from p+A to Au+Au collisions.

Energetic particle populations such as fusion alphas, beams and RF tails can drive a wide variety of shear Alfven instabilities in toroidal confinement systems. These instabilities lead to enhanced loss of fast ions and decreased heating efficiencies. Our gyrofluid stability model has recently been extended to include sheared plasma flow velocities. We also discuss recent results from applying this model to ITER, TFTR, and W7-AS.

Several perovskite-structure oxide compounds, including CaTiO{sub 3}, SrTiO{sub 3}, BaTiO{sub 3}, KNbO{sub 3}, and KTaO{sub 3} were irradiated by 800 keV Kr{sup +} ions in order to investigate and compare their response to heavy-ion irradiation. The critical amorphization temperature T{sub c}, above which amorphization temperature T{sub c}, above which amorphization could not be induced, was found to increase in the order SrTiO{sub 3} {yields} CaTiO{sub 3} {yields} BaTiO{sub 3} {yields} KNbO{sub 3} {yields} KTaO{sub 3}. No single physical parameter explains the observed sequence, although T{sub c} correlates well with the melting temperatures. The well-known temperature-driven phase transformations in these materials did not have a significant effect on the dose required for amorphization. Domain boundaries were observed in the pristine samples; however, after only a low dose, the boundaries became poorly defined and, with increasing dose, eventually disappeared. Dislocation loops were observed to aggregate at the domain boundaries.

The tubular design of solid oxide fuel cells (SOFCs) and the materials used therein have been validated by successful, continuous electrical testing over 69,000 h of early technology cells built on a calcia-stabilized zirconia porous support tube (PST). In the latest technology cells, the PST has been eliminated and replaced by a doped lanthanum manganite air electrode tube. These air electrode supported (AES) cells have shown a power density increase of about 33% with a significantly improved performance stability over the previously used PST type cells. These cells have also demonstrated the ability to thermally cycle over 100 times without any mechanical damage or performance loss. In addition, recent changes in processes used to fabricate these cells have resulted in significant cost reduction. This paper reviews the fabrication and performance of the state-of-the-art AES tubular cells. It also describes the materials and processing studies that are underway to further reduce the cell cost, and summarizes the recently built power generation systems that employed state-of-the-art AES cells.

Precision grinding of optical components is becoming an accepted practice for rapidly and deterministically fabrication optical surfaces to final or near-final surface finish and figure. In this paper, a comparison of grinding techniques and materials is performed. Flat and spherical surfaces were ground in three different substrate materials: BK7 glass, chemical vapor deposited (CVD) silicon carbide ceramic, and sapphire. Spherical surfaces were used to determine the contouring capacity of the process, and flat surfaces were used for surface finish measurements. The recently developed Precitech Optimum 2800 diamond turning and grinding platform was used to grind surfaces in 40mm diameter substrates sapphire and silicon carbide substrates and 200 mm BK7 glass substrates using diamond grinding wheels. The results of this study compare the surface finish and figure for the three materials.