This paper introduces new octant-range, composite-type Gauss and mid-point rule angular quadrature formulas for neutron and photon transport computations. A generalization to octant-range quadratures is also introduced in order to allow for discontinuities at material interfaces for two- and three-dimensional transport problems which can be modeled with 60-degree triangular or hexagonal mesh subdivisions in the x-y plane.

A surface-micromachined two-degree-of-freedom system that was driven by parallel-plate actuation at antiresonance was demonstrated. The system consisted of an absorbing mass connected by folded springs to a drive mass. The system demonstrated substantial motion amplification at antiresonance. The absorber mass amplitudes were 0.8-0.85 pm at atmospheric pressure while the drive mass amplitudes were below 0.1 pm. Larger absorber mass amplitudes were not possible because of spring softening in the drive mass springs. Simple theory of the dual-mass oscillator has indicated that the absorber mass may be insensitive to limited variations in strain and damping. This needs experimental verification. Resonant and antiresonant frequencies were measured and compared to the designed values. Resonant frequency measurements were difficult to compare to the design calculations because of time-varying spring softening terms that were caused by the drive configuration. Antiresonant frequency measurements were close to the design value of 5.1 kHz. The antiresonant frequency was not dependent on spring softening. The measured absorber mass displacement at antiresonance was compared to computer simulated results. The measured value was significantly greater, possibly due to neglecting fringe fields in the force expression used in the simulation.

Within the next few decades, several hundred thousand tons of metal and several million cubic meters of concrete are expected to be removed from nuclear facilities across the US Department of Energy (DOE) complex as a result of decontamination and decommissioning (D&D) activities. These materials, together with large quantities of tools, equipment, and other items that are commonly recovered from site cleanup or D&D activities, constitute non-real properties that warrant consideration for release from regulatory control for reuse or recycle, as permitted and practiced under current DOE policy. The provisions for implementing this policy are contained in the Draft Handbook for Controlling Release for Reuse or Recycle of Non-Real Property Containing Residual Radioactive Material published by DOE in 1997 and distributed to DOE Field Offices for interim use and implementation. This manual describes a computer management tool, P2Pro(RSM), that implements the first 5 steps of the 10-step process stipulated by the Handbook. P2Pro(RSM) combines an easy-to-use Windows interface with a comprehensive database to facilitate the development of authorized release limits for non-real property.

Validation of material models in a variety of scientific and technological applications requires accurate data regarding the high-pressure thermodynamic and mechanical properties. Traditional laboratory techniques for striking these measurements involve light gas guns to generate the required thermodynamic states, and the use of high-resolution time-resolved diagnostics to measure the desired material properties. EOS and constitutive material properties of importance to modeling needs include high-pressure Hugoniot curves and off-Hugoniot properties, such as. material strength and isentropic compression and decompression [1]. Conventional light gas guns are limited to impact pressures of about 7 Mbar in high-impedance materials. Pulsed radiation sources, such as high-intensity lasers, and pulsed power techniques significantly extend the accessible pressures and are becoming accepted methods for meeting the needs of material models in regimes inaccessible by gas guns. A present limitation of these new approaches is that samples must necessarily be small, typically a few tens of microns in thickness, which severely limits the accuracy of EOS measurements that can be made and also the ability to perform a variety of off-Hugoniot measurements. However, recent advances in z-pinch techniques for high-pressure material response studies provide potential opportunities for achieving accuracies comparable with gas guns because of the significantly larger …

We have applied ultraviolet Thomson scattering to accurately measure the electron and ion temperature in high-density gas-filled hohlraums at the Nova laser facility. The implementation of a short-wavelength probe laser that operates at 263 nm (4{omega}) has allowed us for the first time to investigate scalings to high gas fill densities and to characterize the hohlraum conditions of the low-Z gas plasma. as well as of the high-Z wall plasma. These measurements have provided us with a unique data set that we use to make critical comparisons with radiation-hydrodynamic modeling using the code LASNEX. This code is presently being applied to design fusion targets for the National Ignition Facility. The Thomson scattering experiments show the existence of electron temperature gradients in the gas plasma that are well modeled when including a self-consistent calculation of magnetic fields. The fields are of relatively small strength not affecting the Thomson scattering spectra directly but limiting the electron thermal transport in the gas resulting into temperature gradients consistent with the experimental observations. In addition, the ion temperature data show that the stagnation time of the gas plasma on the hohlraum axis, which is driven by the radial inward flowing plasma, is sensitive to the …

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An ink coating method was developed for CIS absorber deposition. The technique involves four processing steps: (1) preparation of a Cu-In alloy powder, (2) preparation of an ink using this powder, (3) deposition of the ink on a substrate in the form of a precursor layer, and (4) selenization to convert the Cu-In precursor into a fused CIS film. Absorbers grown by this low-cost, large-area method were used in the fabrication of 10.5% efficient solar cells.

A molecular dynamics (MD) analysis of conservation of momentum through a shock front is presented. The MD model uses a non-traditional boundary condition that allows simulation in the reference frame of the shock front. Higher order terms proportional to gradients in the density are shown to be non-negligible at the shock front. The simulation is used to study the sequence of thermodynamic states during shock loading. Melting is observed in the simulations, though above the thermodynamic melt curve as is common in homogeneous simulations of melting. High strain-rate tensile loading is applied to the growth of nanoscale voids in copper. Void growth is found to occur by plasticity mechanisms with dislocations emerging from the void surface. [molecular dynamics, shock loading, conservation of momentum, shock melting, void growth]

Experimental conditions are studied to optimize transient experiments for estimating temperature dependent thermal conductivity and volumetric heat capacity. Thermal properties are assumed to vary linearly with temperature; a total of four parameters describe linearly varying thermal conductivity and volumetric heat capacity. A numerical model of experimental configurations is studied to determine the optimum conditions to conduct the experiment. The criterion D-optimality is used to study the sensor locations, heating duration and magnitude, and experiment duration for finite and semi-infinite configurations. Results indicate that D-optimality is an order of magnitude larger for the finite configuration and hence will provide estimates with a smaller confidence region.

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A new analysis technique using high-energy helium ions for the simultaneous elastic recoil detection of all three hydrogen isotopes in metal hydride systems extending to depths of several {micro}m's is presented. Analysis shows that it is possible to separate each hydrogen isotope in a heavy matrix such as erbium to depths of 5 {micro}m using incident 11.48MeV {sup 4}He{sup 2} ions with a detection system composed of a range foil and {Delta}E-E telescope detector. Newly measured cross sections for the elastic recoil scattering of {sup 4}He{sup 2} ions from protons and deuterons are presented in the energy range 10 to 11.75 MeV for the laboratory recoil angle of 30{degree}.

Direct metal deposition technologies produce complex, near net shape components from CAD solid models. Most of these techniques fabricate a component by melting powder in a laser weld pool, rastering this weld bead to form a layer, and additively constructing subsequent layers. This talk describes a new direct metal deposition process, known as WireFeed, whereby a small diameter wire is used instead of powder as the feed material to fabricate components. Currently, parts are being fabricated from stainless steel. Microscopy studies show the WireFeed parts to be fully dense with fine microstructural features. Initial mechanical tests show stainless steel parts to have good strength values with retained ductility.

Despite the current worldwide oil glut, the US will ultimately require large-scale production of liquid (transportation) fuels from coal. Slurry phase Fischer-Tropsch (F-T) technology, with its versatile product slate, may be expected to play a major role in production of transportation fuels via indirect coal liquefaction. Some of the F-T catalysts synthesized and tested at Texas A and M University under DOE Contract No. DE-AC22-89PC89868 were more active than any other known catalysts developed for maximizing production of high molecular weight hydrocarbons (waxes). The objectives of the present contract were to demonstrate repeatability of catalyst performance and reproducibility of preparation procedures of two of these catalysts on a laboratory scale. Improvements in the catalyst performance were attempted through the use of: (a) higher reaction pressure and gas space velocity to maximize the reactor productivity; (b) modifications in catalyst preparation steps; and (c) different pretreatment procedures. Repeatability of catalyst performance and reproducibility of catalyst synthesis procedure have been successfully demonstrated in stirred tank slurry reactor tests. Reactor space-time-yield was increased up to 48% by increasing reaction pressure from 1.48 MPa to 2.17 MPa, while maintaining the gas contact time and synthesis gas conversion at a constant value. Use of calcination temperatures …

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Synchrotron X-ray microtomography shows vesicular structures for toluene/cement mixtures, prepared with 1.22 to 3.58 wt% toluene. Three-dimensional imaging of the cured samples shows spherical vesicles, with diameters ranging from 20 to 250 {micro}m; a search with EPMA for vesicles in the range of 1-20 {micro}m proved negative. However, the total vesicle volume, as computed from the microtomography images, accounts for less than 10% of initial toluene. Since the cements were cured in sealed bottles, the larger portion of toluene must be dispersed within the cement matrix. Evidence for toluene in the cement matrix comes from {sup 29}Si MAS NMR spectroscopy, which shows a reduction in chain silicates with added toluene. Also, {sup 2}H NMR of d{sub 8}-toluene/cement samples shows high mobility for all, toluene and thus no toluene/cement binding. A model that accounts for all observations follows: For loadings below about 3 wt%, most toluene is dispersed in the cement matrix, with a small fraction of the initial toluene phase separating from the cement paste and forming vesicular structures that are preserved in the cured cement. Furthermore, at loadings above 3 wt%, the abundance of vesicles formed during toluene/cement paste mixing leads to macroscopic phase separation (most toluene floats to …

This report presents data obtained on 241-SY-101 pump performance. The period covered is January 1 through March 31, 1999. During the quarter: There were changes in pumping parameters. Both the pump volute pressure and amperage decreased during the quarter. It is not clear whether this was due to changes in waste properties (due to less solids or more entrained gas) or due to degradation of the pump. There was an indication of a 7.5-inch increase in the waste level at riser 1 A, and an average growth rate of 0.082 inches per day. There was an indication of a 5.7-inch increase in the waste level at riser 1C. This riser was flushed with water several times, which would lower the level of the crust at this location. Gases continued to be released at less than the pre-pump installation baseline rate, indicating a decrease in the gas generation rate, or an increase in gas retention, or both. The release rate was about 78 percent of the rate in the previous few quarters, and only 34 percent of the generation rate calculated prior to mixer pump installation in 1993. Key controls exist for waste temperature, gas concentration, pump parameters, and long-term waste …

A new test methodology is described which allows access to loading rates that lie between split Hopkinson bar and shock-loading techniques. Gas gun experiments combined with velocity interferometry techniques have been used to experimentally determine the intermediate strain-rate loading behavior of Coors AD995 alumina and Cercom silicon-carbide rods. Graded-density materials have been used as impactors; thereby eliminating the tension states generated by the radial stress components during the loading phase. Results of these experiments demonstrate that the time-dependent stress pulse generated during impact allows an efficient transition from the initial uniaxial strain loading to a uniaxial stress state as the stress pulse propagates through the rod. This allows access to intermediate loading rates over 5 x 10{sup 3}/s to a few times 10{sup 4}/s.

For many applications, the device performance of edge emitting semiconductor lasers can be significantly improved through the use of multiple section devices. For example, cleaved coupled cavity (C3) lasers have been shown to provide single mode operation, wavelength tuning, high speed switching, as well as the generation of short pulses via mode-locking and Q-switching [1]. Using composite resonators within a vertical cavity laser opens up new possibilities due to the unique ability to tailor the coupling between the monolithic cavities, incorporate passive or active resonators which are spectrally degenerate or detuned, and to fabricate these devices in 2-dimensional arrays. Composite resonator vertical cavity lasers (CRVCL) have been examined using optical pumping and electrical injection [2-5]. We report on CRVCL diodes and show that efficient modulation of the laser emission can be achieved by either forward or reverse biasing the passive cavity within a CRVCL.

The purpose of this calculation is to create a high-level estimation of the weights and volume of the commercial spent nuclear fuel (SNF) assemblies, at the time of repository receipt, that will comprise 63,000 metric tons of uranium (MTU) waste. The results of this calculation are for informational purposes only and are not intended to be used as input to design documents. This calculation was prepared in accordance with procedure AP-3.12Q REV 00 ICN 0, Calculations.

An ultrasonic sensor system and method of use for measuring transit time through a liquid sample, comprising at least one ultrasonic transducer coupled to a precision time interval counter. The timing circuit captures changes in transit time, representing small changes in the velocity of sound transmitted, over necessarily small time intervals (nanoseconds) and uses the transit time changes to identify the presence of non-conforming constituents in the sample.

At ultrarelativistic energies, ionization cross sections exceed electron capture cross sections by several orders of magnitude (1,2). Effectively, all electrons transferred to a highly relativistic heavy ion moving in a solid or gaseous target medium are stripped in a relatively short distance. Above ~20 GeV/nucleon, the principal mechanism for electron capture is from pair production (ECPP) (2). The total cross sections for ECPP are te&nically important for making reliable predictions of operating limitations for relativistic heavy-ion colliders, e.g., RHIC and LHC (3). In ECPP, it is expected that ~30% of capture proceeds to excited states of the capturing ion. Some of these relatively weakly bound electrons are radiatively long-lived and easily lost in secondary collisions in solid targets, making measurements of their contributions to total capture experimentally difficult. Electrons lost from high-energy ions in collisions with target atoms form a cusp-shaped spectral peak in the forward direction in the laboratory frame centered at the velocity of the moving ion (4-5). The shape of this electron loss to projectile continuum (ELC) peak has been shown (5,6) to depend on the initial atomic bound state from which the electron is ionized. We have measured and compared ELC electrons from direct ionization of …

I present an overview of radiation monitoring for vertex detectors and the abort system for the Fermilab Tevatron. Details on the detectors, inputs, and measurements for the Run 1 time period are provided. Plans for the monitoring during Run 2 are discussed. The measurements imply an approximately even mix of radiation from beam-beam collisions and beam losses.