This paper describes a simple 2D beam-rastering system to uniformly spread a 100-mA 6.7-MeV cw proton beam over a 50-cm by 50-cm beam stop. The basic circuit uses a 20-mF capacitor bank, a IGBT (insulated gate bipolar transistor) full-wave inverter, and a 1-mH ferrite dipole magnet to produce a {+-} 500-Gauss peak triangular-waveform deflection field at 500 Hz. A dc input voltage of 200 volts at 2.6 amps (520 watts) produces a 160-ampere peak-to-peak triangular current waveform in the ferrite magnet at 500 Hz. For dual-axis rastering, two ferrite dipoles are used, one at 500 Hz, and the other at 575 Hz, to produce a uniform 2D beam distribution at the beam stop. The paper will discuss the IGBT modulator and ferrite deflector in detail, including current and voltage waveforms, and the ferrite magnet B-dot (dB/dt) signal.

The Department of Energy held its annual Technical Standards Program Workshop on July 8--10, 1997, at the Loews L`Enfant Plaza Hotel in Washington, DC. The workshop focused on aspects of implementation of the National Technology Transfer and Advancement Act of 1995 [Public Law (PL) 104-113] and the related revision (still pending) to OMB Circular A119 (OMB A119), Federal Participation in the Development and Use of Voluntary Standards. It also addressed DOE`s efforts in transitioning to a standards-based operating culture, and, through this transition, to change from a developer of internal technical standards to a customer of external technical standards. The workshop was designed to provide a forum to better understand how the new law is affecting Department activities. Panel topics such as ``Public Law 104-113 and Its Influence on Federal Agency Standards Activities`` and ``Update on Global Standards Issues`` provided insight on both the internal and external effects of the new law. Keynote speaker Richard Meier of Meadowbrook International (and formerly the Deputy Assistant US Trade Representative) addressed the subject of international trade balance statistics. He pointed out that increases in US export figures do not necessarily indicate increases in employment. Rather, increased employment results from product growth. Mr Meier …

This paper presents data that supports Accelerator Mass Spectrometry (AMS) as a valid bioanalytical tool for tracing long lived radioisotopes in uses as molecular labels or elemental tracers.

The TRUEX process is being evaluated at the Idaho Chemical Processing Plant (ICPP) for the separation of the actinides from acidic radioactive wastes stored at the ICPP. These efforts have culminated in a recent demonstration of the TRUEX process with actual tank waste. This demonstration was performed using 24 stages of 2-cm diameter centrifugal contactors installed in a shielded hot cell at the ICPP Remote Analytical Laboratory. An overall removal efficiency of 99.97% was obtained for the actinides. As a result, the activity of the actinides was reduced from 457 nCi/g in the feed to 0.12 nCi/g in the aqueous raffinate, which is well below the U.S. NRC Class A LLW requirement of 10 nCi/g for non-TRU waste. Iron was partially extracted by the TRUEX solvent, resulting in 23% of the Fe exiting in the strip product. Mercury was also extracted by the TRUEX solvent (76%) and stripped from the solvent in the 0.25 M Na{sub 2}CO{sub 3} wash section.

In this paper the authors present an adaptive projection method for modeling unsteady, low-Mach reacting flow in an unconfined region. The equations they solve are based on a model for low-Mach number combustion that consists of the evolution equations for density, species concentrations, enthalpy, and momentum coupled with a constraint on the divergence of the flow. The algorithm is based on a projection methodology in which they first advance the evolution equations and then solve an elliptic equation to enforce the divergence constraint. The adaptive mesh refinement (AMR) scheme uses a time-varying, hierarchical grid structure composed of uniform rectangular grids of varying resolution. The integration scheme on the grid hierarchy is a recursive procedure in which a coarse grid is advanced, fine grids are advanced multiple steps to reach the same time as the coarse grid, and the coarse and the fine grids are synchronized. The method is valid for multiple grids on each level and multiple levels of refinement. The method is currently implemented for laminar, axisymmetric flames with a reduced kinetics mechanism and a Lewis number of unity. Two methane-air flames, one steady and the other flickering, are presented as numerical examples.

The Advanced Photon Source at Argonne National Laboratory is now providing researchers with extreme-brilliance undulator radiation in the hard x-ray region of the spectrum. All technical facilities and components are operational and have met design specifications. Fourteen research teams, occupying 20 sectors on the APS experiment hall floor, are currently installing beamline instrumentation or actively taking data. An overview is presented for the first operational years of the Advanced Photon Source. Emphasis is on the performance of accelerators and insertion devices, as well as early scientific results and future plans.

Our studies of the shock compression response of PVDF polymer are continuing in order to understand the physical properties under shock loading and to develop high fidelity, reproducible, time-resolved dynamic stress gauges. New PVDF technology, new electrode configurations and piezoelectric analysis have resulted in enhanced precision gauges. Our new standard gauges have a precision of better than 1% in electric charge release under shock up to 15 GPa. The piezoelectric response of shock compressed PVDF gauges 1 mm{sup 2} in active area has been studied and yielded well-behaved reproducible data up to 20 GPa. Analysis of the response of these gauges in the {open_quotes}thin mode regime{close_quotes} using a Lagrangian hydrocode will be presented. P(VDF-TrFE) copolymers exhibit unique piezoelectric properties over a wide range of temperature depending on the composition. Their properties and phase transitions are being investigated. Emphasis of the presentation will be on key results and implications.

Laboratory data are presented on the thermal conductivity of polyurethane foam insulation in composite test panels that simulate refrigerator walls. The test panels consisted of a steel skin, an ABS plastic liner, and a polyurethane foam core. Foam cores were produced with three different blowing agents (CFC-11, HCFC-141b, and a HCFC-142/22 blend). Periodic thermal measurements have been made on these panels over a three and one half year period in an effort to detect aging processes. Data obtained on foam encased in the panels were compared with measurements on thin foam slices that were removed from similar panels. The data show that the encapsulation of the foam in the solid boundary materials greatly reduces the aging rate. The plan is presented for a follow-on project that is being conducted on the aging of foams blown with HCFC-141b, HFC-134a, HFC-245fa, and cyclopentane.

The Los Alamos Neutron Science Center (LANSCE) 800 MeV proton linear accelerator (linac) operates at a maximum repetition rate of twice the AC power line frequency, i.e. 120 Hz. The start of each machine cycle occurs a fixed delay after each zero-crossing of the AC line voltage. Fluctuations in the AC line frequency and phase are therefore present on all linac timing signals. Proper beam acceleration along the linac requires that the timing signals remain well synchronized to the AC line. For neutron chopper spectrometers, e.g., PHAROS at the Manuel Lujan Jr. Neutron Scattering Center, accurate neutron energy selection requires that precise synchronization be maintained between the beam-on-target arrival time and the neutron chopper rotor position. This is most easily accomplished when the chopper is synchronized to a stable, fixed frequency signal. A new zero-crossing circuit which employs a Phase-Locked Loop (PLL) has been developed to increase the phase and frequency stability of the linac timing signals and thereby improve neutron chopper performance while simultaneously maintaining proper linac operation. Results of timing signal data analysis and modeling and a description of the PLL circuit are presented.

The central Radiological Control Organization, originally under the previous Management and Operations contractor (Westinghouse Hanford Company) decided that a significant improvement in ALARA implementation would result if examples of engineered controls used for radiological work were assembled in one location to provide a ``showcase`` for workers and managers. The facility would be named the ALARA Center of Technology (ACT) and would include the latest technologies used to accomplish radiological work, as well as proven techniques, tools, and equipment. A location for the Center was selected in the 200 East Area of Hanford in a central location to be easily accessible to all facilities and contractors. Since there was little money available for this project, a decision was made to contact several vendors and request loans of their tools, equipment, and materials. In return, the center would help market products on site and assist with product demonstrations when the vendors visited Hanford. Out of 28 vendors originally contacted, 16 responded with offers to loan products. This included a containment tent, several glove bags, BEPA filtered vacuum cleaners, portable ventilation systems, fixatives, temporary shielding, pumps, and several special tools. Vendors who could not provide products sent videos and brochures. Westinghouse Hanford Company …

The 113-kg Array of Low Energy X-ray Imaging Sensors (ALEXIS) satellite was launched from the fourth flight of Pegasus on 25 April, 1993 into a 750 x 850 km, 70 degree inclination orbit. Due to damage sustained at the time of launch, ground controllers did not make contact with the satellite until late June. By late July, full satellite operations had been restored through the implementation of new procedures for attitude control. Science operations with the two onboard experiments began at that time. Now 4 years later is still collecting more than 100 MB of mission data per day. ALEXIS was originally designed to be a high risk, single string. {open_quotes}Smarter-Faster-Cheaper{close_quotes} satellite, with a 1 year nominal and a 3 year design limit. This paper will discuss how well the various satellite and experiment subsystems are surviving a variety of low and high radiation environments and what improvements have been made to make operations more autonomous. 11 refs., 2 figs., 2 tabs.

An amp-hour counting battery charge control algorithm has been defined and tested using the Digital Solar Technologies MPR-9400 microprocessor based photovoltaic hybrid charge controller. This work included extensive laboratory and field testing of the charge algorithm on vented lead-antimony and valve regulated lead-acid batteries. The test results have shown that with proper setup amp-hour counting charge control is more effective than conventional voltage regulated sub-array shedding in returning the lead-acid battery to a high state of charge.

The burning of liquid propellants is a fundamental combustion problem that is applicable to various types of propulsion and energetic systems. The deflagration process is often rather complex, with vaporization and pyrolysis occurring at the liquid/gas interface and distributed combustion occurring either in the gas phase or in a spray. Nonetheless, there are realistic limiting cases in which combustion may be approximated by an overall reaction at the liquid/gas interface. In one such limit, distributed combustion occurs in an intrusive regime, the reaction zone lying closer to the liquid/gas interface than the length scale of any disturbance of interest. Such limiting models have recently been formulated thereby significantly generalizing earlier classical models that were originally introduced to study the hydrodynamic stability of a reactive liquid/gas interface. In all of these investigations, gravity appears explicitly and plays a significant role, along with surface tension, viscosity, and, in the more recent models, certain reaction-rate parameters associated with the pressure and temperature sensitivities of the reaction itself. In particular, these parameters determine the stability of the deflagration with respect to not only classical hydrodynamic disturbances, but also with respect to reactive/diffusive influences as well. These instabilities thus lead to a number of interesting …

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We compare the thermo-elastic-plastic response of fissionable metals calculated by the solid mechanics code DYNA to an analytic model for the case of a uniformly heated thin spherical shell and to experimental data for the case of a thin rod heated in a pulsed reactor. In both cases, the materials are volumetrically heated by neutron exposure. We find good agreement between the code and the analytic model and experimental data for the first and second case, respectively. For very fast heating times, macroscopic displacement may be replaced by microscopic plastic flow. To verify this behavior, an experiment to be done at SNLA SPR III is described. Validation of the code in these simple geometries is a necessary step if calculations involving more complicated geometries are to be understood and trusted.

The frictional properties of sliding metal interfaces at high velocities are not well known from either an experimental or theoretical point of view. The constitutive properties and macroscopic laws of frictional dynamics at high velocities necessary for materials continuum codes have only a qualitative validity and it is of interest to have analytic problems for sliding interfaces to enable separation of model from numerical effects. The authors present an exact solution for the space and time dependence of the plastic strain near a sliding interface in a planar semi-finite geometry. This solution is based on a particular form for the strain rate dependence of the flow stress and results in a hyperbolic telegrapher equation for the plastic strain. The form of the solutions and wave structure will be discussed.

This work considers the problem of maximum utilization of a set of mobile robots with limited sensor-range capabilities and limited travel distances. The robots are initially in random positions. A set of robots properly guards or covers a region if every point within the region is within the effective sensor range of at least one vehicle. The authors wish to move the vehicles into surveillance positions so as to guard or cover a region, while minimizing the maximum distance traveled by any vehicle. This problem can be formulated as an assignment problem, in which they must optimally decide which robot to assign to which slot of a desired matrix of grid points. The cost function is the maximum distance traveled by any robot. Assignment problems can be solved very efficiently. Solutions times for one hundred robots took only seconds on a Silicon Graphics Crimson workstation. The initial positions of all the robots can be sampled by a central base station and their newly assigned positions communicated back to the robots. Alternatively, the robots can establish their own coordinate system with the origin fixed at one of the robots and orientation determined by the compass bearing of another robot relative to …

The Caspian basin blocks the propagation of the regional seismic phase Lg and this has importance consequences for seismic discrimination in the Middle East. Intermediate period surface waves propagating across the basin are also severely affected. In a separate study we have developed a crustal model of the south Caspian basin and the surrounding region. The crust of the basin consists of 15-25 km of low velocity, highly attenuating sediments lying on high velocity crystalline crust. The Moho beneath the basin is at a depth of about 30 km as compared to about 50 km in the surrounding region. In this study we used an idealized rendition of this crustal model to compute hybrid normal mode finite difference synthetic seismograms to identify the features of the Caspian basin which lead to the seismic blockage. Of the various features of the basin, the thickness and attenuation of the sediments appear to be the dominant blocking mechanism.

Atmospheric turbulence causes several effects on a propagating laser beam. The authors have previously studied the effects of beam spreading and beam wander, and feel they have a good understanding of their impact on CO{sub 2} DIAL. Another effect is scintillation where atmospheric turbulence causes irradiance fluctuations within the envelope of the beam profile. They believe that scintillation at the target plays an important role in LIDAR return statistics. A Huygens-Fresnel wave optics computer simulation for propagating beams through atmospheric optical turbulence has been previously developed. They modify this simulation to include the effects of reflective speckle and examine its application in comparison with experimental data.

The Department of Energy has submitted to the NRC staff for review a topical safety analysis report (TSAR) for a Centralized Interim Storage Facility (CISF). The TSAR will be used in licensing the CISF when and if a site is designated. CISF1 design events are identified based on thorough review of design basis events (DBEs) previously identified by dry storage system suppliers and licensees and through the application of hazard assessment techniques. A Preliminary Hazards Assessment (PHA) is performed to identify design events applicable to a Phase 1 non site specific CISF. A PHA is deemed necessary since the Phase 1 CISF is distinguishable from previous dry store applications in several significant operational scope and design basis aspects. In addition to assuring all design events applicable to the Phase 1 CISF are identified, the PHA served as an integral part of the CISF design process by identifying potential important to safety and defense in depth facility design and administrative control features. This paper describes the Phase 1 CISF design event identification process and summarizes significant PHA contributions to the CISF design.

A systems engineering approach to programmatic risk assessment, derived from the aerospace industry, was applied to various stabilization technologies to assess their relative maturity and availability for use in stabilizing nuclear materials. The assessment provided valuable information for trading off available technologies and identified the at-risk technologies that will require close tracking by the Department of Energy (DOE) to mitigate programmatic risks.

A systems engineering approach to programmatic risk assessment, derived from the aerospace industry, was applied to various stabilization technologies to assess their relative maturity and availability for use in stabilizing nuclear materials. The assessment provided valuable information for trading off available technologies and identified the at-risk technologies that will require close tracking by the Department of Energy (DOE) to mitigate programmatic risks. This paper presents the programmatic risk assessment methodology developed for the 1995 R and D Plan and updated for the 1996 R and D Plan. Results of the 1996 assessment also are presented (DOE/ID-10561, 1996).

The Argonne Wakefield Accelerator is presently operational and nearing completion of its initial dielectric structure- and plasma-based experimental program. In this paper a number of possible future improvements and directions for the AWA are discussed including photocathode source upgrades, laser pulse and beam shaping options, multiple drive bunch generation, and novel wakefield device measurements. Plans for a 1 GeV demonstration wakefield accelerator will be presented.

Reserve appreciation, also called reserve growth, is the increase in the estimated ultimate recovery (the sum of year end reserves and cumulative production) from fields subsequent to discovery from extensions, infield drilling, improved recovery of in-place resources, new pools, and intrapool completions. In recent years, reserve appreciation has become a major component of total U.S. annual natural gas reserve additions. Over the past 15 years, reserve appreciation has accounted for more than 80 percent of all annual natural gas reserve additions in the U.S. lower 48 states (Figure 1). The rise of natural gas reserve appreciation basically came with the judgment that reservoirs were much more geologically complex than generally thought, and they hold substantial quantities of natural gas in conventionally movable states that are not recovered by typical well spacing and vertical completion practices. Considerable evidence indicates that many reservoirs show significant geological variations and compartmentalization, and that uniform spacing, unless very dense, does not efficiently tap and drain a sizable volume of the reservoir (Figure 2). Further, by adding reserves within existing infrastructure and commonly by inexpensive recompletion technology in existing wells, reserve appreciation has become the dominant factor in ample, low-cost natural gas supply. Although there is …