An imaging Raman microscope is used to detect and image phases in high-{Tc} superconductor powders, pellets, and silver-sheathed composites. The procedure involves the following series of measurements: (1) spot-focused (< 5 {micro}m) Raman microprobe spectral measurements on isolated crystallites; (2) defocused (3 50 {micro}m) Raman microprobe spectral measurements on isolated crystallites and surrounding area; (3) Raman spatial images of each band in the defocused Raman spectrum; and (4) spot-focused Raman microprobe spectral measurements on selected regions of Raman imaged area (to confirm findings of Raman image analysis). Materials studied were (Bi,Pb){sub 3}Sr{sub 2}Ca{sub 2}Cu{sub 1}O{sub x}, (Ca,Sr){sub 2}CuO{sub 3}, (Ca,Sr){sub 14}Cu{sub 24}O{sub 41}, and Ag/Bi-2223 composite.

There is a need for real time, reliable density measurement for density control, compatible with the restricted access and radiation environment on ITER. Line average density measurements using microwave or laser interferometry techniques have proven to be robust and reliable for density control on contemporary tokamaks. In ITER, the large path length, high density and density gradients, limit the wavelength of a probing beam to shorter then about 50 {micro}m due to refraction effects. In this paper the authors consider the design of short wavelength vibration compensated interferometers and Faraday rotation techniques for density measurements on ITER. These techniques allow operation of the diagnostics without a prohibitively large vibration isolated structure and permits the optics to be mounted directly on the radial port plugs on ITER. A beam path designed for 10.6 {micro}m (CO2 laser) with a tangential path through the plasma allows both an interferometer and a Faraday rotation measurement of the line average density with good density resolution while avoiding refraction problems. Plasma effects on the probing beams and design tradeoffs will be discussed along with radiation and long pulse issues. A proposed layout of the diagnostic for ITER will be present.

The TRUEX solvent extraction process is being developed to remove and concentrate transuranic (TRU) elements from high-level and TRU radioactive wastes currently stored at US Department of Energy sites. Phosphoric acid is one of the chemical species of concern at the Hanford site where bismuth phosphate was used to recover plutonium. The mechanism of phosphoric acid extraction with TRUEX-NPH solvent at 25{degrees}C was determined by phosphoric acid distribution ratios, which were measured by using phosphoric acid radiotracer and a variety of aqueous phases containing different concentrations of nitric acid and nitrate ions. A model was developed for predicting phosphoric acid distribution ratios as a function of the thermodynamic activities of nitrate ion and hydrogen ion. The Generic TRUEX Model (GTM) was used to calculate these activities based on the Bromley method. The derived model supports CMPO and TBP extraction of a phosphoric acid-nitric acid complex and a CMPO-phosphoric acid complex in TRUEX-NPH solvent.

Because of the complexity, volume of data and calculations required, one preferred analytical tool to perform transportation risk assessments is the RADTRAN computer code. RADTRAN combines user-determined material, packaging, transportation, demographic and meteorological factors, with health physics data to calculate expected radiological consequences and accident risk from transporting radioactive materials by all commercial modes including truck, rail, ship, air and barge. The computer code consists of two major modules for each transport mode: the incident-free module, in which doses from normal transport are calculated; and the accident module, in which dose consequences and probabilities are evaluated to generate risk estimates. The purpose of this presentation is to describe the development of a standardized procedure to perform transportation radiological risk assessments employing conventional spreadsheet programs to automate generation of RADTRAN input files and post-processing analysis of the resulting output.

SDDS is a file protocol for Self Describing Data Sets. This document describes Version 1 of the SDDS protocol and the function library that supports it. It is intended for those who wish to develop programs that use SDDS files.

The Supercell option of the WIMS-D4M code is used with a model for the Advanced Neutron Source design to illustrate the capability, and the results are compared with Monte Carlo. The capability is also used to successfully model Russian designed fuel assemblies with concentric tubes. The capability to model homogenized and resonance corrected fuel and to properly treat secondary regions containing resonance materials is particularly useful. The Supercell option is well suited to modeling non-lattice regions, such as, reflector, control and/or experimental regions of research reactors.

The gradual buildup of rare isotopes from interactions between cosmic rays and atoms in an exposed rock provides a new method of directly determining the exposure age of rock surfaces. The cosmogenic nuclide method can also provide constraints on erosion rates and the length of time surface exposure was interrupted by burial. Numerous successful applications of the technique have been imperative to the complete surface geologic characterization of Yucca Mountain, Nevada, a potential high level nuclear waste repository. In this short paper, we summarize the cosmogenic nuclide method and describe with examples some the utility of the technique in geologic site characterization. We report preliminary results from our ongoing work at Yucca Mountain.

This presentation will focus on current work in the Ames Laboratory where laser ablation is being used for both analytical sampling and metal surface cleaning. Examples will be presented demonstrating the utility of optical spectroscopy for monitoring laser ablation processes.

These proceedings contain edited versions of the technical presentations of the Workshop on Environmental and Energy Applications of Neural Networks, held on March 30--31, 1995, in Richland, Washington. The purpose of the workshop was to provide a forum for discussing environmental, energy, and biomedical applications of neural networks. Panels were held to discuss various research and development issues relating to real-world applications in each of the three areas. The applications covered in the workshop were: Environmental applications -- modeling and predicting soil, air and water pollution, environmental sensing, spectroscopy, hazardous waste handling and cleanup; Energy applications -- process monitoring and optimization of power systems, modeling and control of power plants, environmental monitoring for power systems, power load forecasting, fault location and diagnosis of power systems; and Biomedical applications -- medical image and signal analysis, medical diagnosis, analysis of environmental health effects, and modeling biological systems. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

The APS accelerator control system is a distributed system consisting of operator interfaces, a network, and computer-controlled interfaces to hardware. This implementation of a control system has come to be called the {open_quotes}Standard Model.{close_quotes} The operator interface is a UNDC-based workstation with an X-windows graphical user interface. The workstation may be located at any point on the facility network and maintain full functionality. The function of the network is to provide a generalized communication path between the host computers, operator workstations, input/output crates, and other hardware that comprise the control system. The crate or input/output controller (IOC) provides direct control and input/output interfaces for each accelerator subsystem. The network is an integral part of all modem control systems and network performance will determine many characteristics of a control system. This paper will describe the overall APS network and examine the APS control system network in detail. Metrics are provided on the performance of the system under various conditions.

The first undulator radiation has been extracted from the Advanced Photon Source (APS). The results from the characterization of this radiation are very satisfactory. With the undulator set at a gap of 15.8 mm (K=1.61), harmonics as high as the 17th were observed using a crystal spectrometer. The angular distribution of the third-harmonic radiation was measured, and the source was imaged using a zone plate to determine the particle beam emittance. The horizontal beam emittance was found to be 6.9 {plus_minus} 1.0 nm-rad, and the vertical emittance coupling was found to be less than 3%. The absolute spectral flux was measured over a wide range of photon energies, and it agrees remarkably well with the theoretical calculations based on the measured undulator magnetic field profile and the measured beam emittance. These results indicate that both the emittance of the electron beam and the undulator magnetic field quality exceed the original specifications.

Current modeling of transfer maps for superconducting RF cavities at CEBAF includes only linear effects. Here we extend the transfer mapping modeling capability to include arbitrary order field information generated from the MAFIA field data. We include coupler kicks, normal and skew quadrupole focussing and higher order effects.

During the CEBAF commissioning tests some of the superconducting cavities had light emitting discharges (arcing) which were observed in the guard vacuum space between a warm polymeric rf window and the cold ceramic rf window. A dedicated off-line test system was implemented to investigate the conditions under which arcing may occur and to gain some understanding of the mechanisms leading to this phenomenon through optical spectral analysis. This paper reports on the photoemission spectra observed during the dedicated tests on a single cell 1500 MHz niobium cavity with a ceramic window operated at 10 MV/m and 2 K. The light emission was detected using a spectrometer with an intensified photodiode array. The effect of moving the window away from the beam line using a waveguide elbow is reported. 12 refs.

Under the Scientific Facilities Initiative, IPNS is planning to double its operation to 32 weeks/yr. Additional scientific and technical support staff will be added for the greatly expanded user program. The IPNS Upgrade Feasibility Study was published in April 1995 and is a thoroughly documented study on a 1-MW pulsed spallation neutron source at Argonne, including cost and schedule. A new booster target ({sup 235}U-Mo alloy) has been designed that will increase the neutron flux by a factor of {approximately}3 and construction will begin soon. A new small angle diffractometer (SAND) is in the final stages of commissioning, a prototype inelastic scattering spectrometer for Chemical Excitations (CHEX) was recently constructed and an upgraded quasielastic spectrometer (QENS) has been designed. IPNS has gained considerable operating experience with solid methane moderators, including controlled heating at periodic intervals in order to anneal the accumulated radiation induced stored energy.

ARIES (Autonomous Robotic Inspection Experimental System) is a mobile robot inspection system being developed for the Department of Energy (DOE) to survey and inspect drums containing mixed and low-level radioactive waste stored in warehouses at DOE facilities. The drums are typically stacked four high and arranged in rows with three-foot aisle widths. The robot will navigate through the aisles and perform an autonomous inspection operation, typically performed by a human operator. It will make real-time decisions about the condition of the drums, maintain a database of pertinent information about each drum, and generate reports.

During this quarter, further progress has been made in accomplishing the objectives of the project. The computational model for simulating particle motions in turbulent flows has been further developed. The model was applied to the analysis of particle transport and deposition processes in a circular duct and in a plane recirculating region. A model for evaluating particle deposition rate in the presence of gravitational and electrical forces in turbulent flows formulated. Results concerning the deposition velocity of particles under various conditions were obtained. It is shown that the model predictions are in good agreement with the available experimental and digital simulation data. Experimental study of glass fiber transport and deposition rate is also being planned.

The workshop focused on six topics, all of which are areas of active research: (1) speciation, reactivity and mobility of contaminants in aqueous systems, (2) the role of surfaces and interfaces in molecular environmental science, (3) the role of solid phases in molecular environmental science, (4) molecular biological processes affecting speciation, reactivity, and mobility of contaminants in the environment, (5) molecular constraints on macroscopic- and field-scale processes, and (6) synchrotron radiation facilities and molecular environmental sciences. These topics span a range of important issues in molecular environmental science. They focus on the basic knowledge required for understanding contaminant transport and fate and for the development of science-based remediation and waste management technologies. Each topic was assigned to a working group charged with discussing recent research accomplishments, significant research opportunities, methods required for obtaining molecular-scale information on environmental contaminants and processes, and the value of synchrotron x-ray methods relative to other methods in providing this information. A special working group on synchrotron radiation facilities was convened to provide technical information about experimental facilities at the four DOE-supported synchrotron radiation sources in the US (NSLS, SSRL, AS and UPS) and synchrotron- based methods available for molecular environmental science research. Similar information on …

The overall objective of this research was to assist in the recovery of this non-contacted oil from known reservoirs on the Outer Continental Shelf in the Gulf of Mexico. This project proceeded under three broad phases: analysis, supporting research, and technology transfer. This final report has been organized into a description of the overall work plan of this project and five volumes. Because of the wide variation and complex coverage of several topics and disciplines, each volume contains its own table of contents, list of tables, list of figures, abstract, executive summary, introduction, subject sections or chapters, acknowledgements, bibliographies, index and appendices.

Depleted uranium hexafluoride (UF{sub 6}) at the US Department of Energy`s K-25 Site at Oak Ridge, TN has been stored in large steel cylinders which have undergone significant atmospheric corrosion damage over the last 35 years. A detailed experimental program to characterize and monitor the corrosion damage was initiated in 1992. Large amounts of corrosion scale and deep pits are found to cover cylinder surfaces. Ultrasonic wall thickness measurements have shown uniform corrosion losses up to 20 mils (0.5 mm) and pits up to 100 mils (2.5 mm) deep. Electrical resistance corrosion probes, time-of-wetness sensors and thermocouples have been attached to cylinder bodies. Atmospheric conditions are monitored using rain gauges, relative humidity sensors and thermocouples. Long-term (16 years) data are being obtained from mild steel corrosion coupons on test racks as well as attached directly to cylinder surfaces. Corrosion rates have been found to intimately related to the times-of-wetness, both tending to be higher on cylinder tops due to apparent sheltering effects. Data from the various tests are compared, discrepancies are discussed and a pattern of cylinder corrosion as a function of cylinder position and location is described.

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Addition of controlled residual elements (CRE), such as 0.007 wt % B, to type 308 stainless steel welds, improved creep-rupture properties. In this paper, B distribution and microstructure development were studied. The microstructural evolution during high-temperature aging was found to similar to that of commercial SS308 welds. Atom probe analysis showed that B and C segregate to the ferrite-austenite interface. Thermodynamic calculations suggest that the segregation is due to preferential partitioning of B and C to the liquid during solidification. Further work is needed to study B redistribution in aging stages.

Pulsed-power driven ion diodes generating quasi-static, {approximately}10 MV/cm, 1-cm scale-length electric fields are used to accelerate lithium ion beams for inertial confinement fusion applications. Atomic emission spectroscopy measurements contribute to understanding the acceleration gap physics, in particular by combining time- and space-resolved measurements of the electric field with the Poisson equation to determine the charged particle distributions. This unique high-field configuration also offers the possibility to advance basic atomic physics, for example by testing calculations of the Stark-shifted emission pattern, by measuring field ionization rates for tightly-bound low-principal-quantum-number levels, and by measuring transition-probability quenching.

Surface x-ray scattering has been used to determine the structure of Tl adlayers on the Au(111) electrode surface during the course of 0{sub 2} reduction. 0. reduction is considerably catalyzed by Ti adlayers on Au(111). The half-wave potential is shifted to more positive values in the presence of the Ti adlayer. In both, acid and alkaline solutions TI causes a change in the reaction mechanism from a 2-ereduction to a 4e-reduction in a limited potential range. The in-plane X-ray diffraction measurements revealed that the close-packed rotated-hexagonal Ti phase, which exists in the potential range between -0.4V and the bulk TI deposition at {approx}{minus} 0.7V, has a lower activity for 0. reduction than the low-coverage phases in both solutions. It supports a 2e-reduction.0{sub 2} reduction does not change the TI coverage in this phase but causes a significant decrease of the in-plane diffracted intensity. The lower coverage phases which exist at more positive potentials, viz., aligned hexagonal in alkaline solution and patches of the (2 {times} 2)TI phase in acid solution, are conducive to a 4e-reduction. The diffraction intensity from these two phases, however, vanishes quickly during O{sub 2} reduction. It appears that the TI coverage remains on the surface unchanged. …

Austenitic superalloys exhibit dramatic reductions in ductility and crack growth resistance when high fugacity hydrogen and hydrogen-producing environments trigger a change in fracture mode from microvoid coalescence to slip band and intergranular fracture. Of particular importance is the change to intergranular fracture. We have therefore combined the Embedded Atom Method (EAM) with Monte Carlo simulations and molecular dynamics calculations to help define the effects of hydrogen on segregation and fracture at the atomic level. Nickel was used to simulate the face-centered-cubic austenite lattice while symmetric and asymmetric {sigma}9 tilt boundaries were used to simulate grain boundaries. These simulations show that grain boundaries are strong trap sites for hydrogen. They further show that hydrogen dramatically reduces the bond strength between atoms at grain boundary sites while inhibiting dislocation generation.