Microtomography has successfully been used to characterize loss of structural integrity of wood. Tomographic images were generated with the newly developed third generation x-ray computed microtomography (XCMT) instrument at the X27A beamline at the National Synchrotron Light Source (NSLS). The beamline is equipped with high-flux x-ray monochromator based on multilayer optics developed for this application. The sample is mounted on a translation stage with which to center the sample rotation, a rotation stage to perform the rotation during data collection and a motorized goniometer head for small alignment motions. The absorption image is recorded by a single-crystal scintillator, an optical microscope and a cooled CCD array detector. Data reconstruction has provided three-dimensional geometry of the heterogeneous wood matrix in microtomographic images. Wood is a heterogeneous material composed of long lignocellulose vessels. Although wood is a strong natural product, fungi have evolved chemical systems that weaken the strength properties of wood by degrading structural vessels. Tomographic images with a resolution of three microns were obtained nonintrusively to characterize the compromised structural integrity of wood. Computational tools developed by Lindquist et al (1996) applied to characterize the microstructure of the tomographic volumes.

We give a pedagogical introduction to hard photoproduction processes at HERA, including the production of jets, hadrons, and prompt photons. Recent theoretical developments in the three areas are reviewed. In summary, hard photoproduction processes can provide very useful information on the hadronic structure of the photon, in particular on the gluon density, which is complimentary to the information coming from deep inelastic photon-photon scattering at electron-positron colliders. Among the different hadronic final states, jets are most easily accessible experimentally and phenomenologically. On the other hand, inclusive hadron production offers the possibility to test the universality of hadron fragmentation functions and measure the photon structure down to very low values of p{sub T} and x{sub {gamma}}. Prompt photon production suffers from a reduced cross section and limited data, but allows for the additional testing of photon fragmentation functions.

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]

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.

A new technique to estimate the shape attribute of plutonium assemblies using the Nuclear Materials Identification System (NMIS) is described. The proposed method possesses a number of advantages. It is passive no external radiation source is required to estimate the shape of plutonium assemblies. Instead, inherent gamma and neutron emissions from spontaneous fission of {sup 240}Pu and subsequent induced fission of {sup 239}Pu are detected to estimate the shape attribute. The technique is also stationary: shape is estimated without scanning the assembly by moving the detectors relative to the assembly. The proposed method measures third order correlations between triplets of gamma/neutron-sensitive detectors. The real coincidence of a pair of gammas is used as a ''trigger'' to approximately identify the time of a spontaneous or induced fission event. The spatial location of this fission event is inferred from the real coincidence of a subsequent neutron with the initial pair of correlated gammas by using the neutron's time-of-flight (approximately the delay between the gamma pair and the neutron) and the fission neutron spectra of {sup 240}Pu and {sup 239}Pu. The spatial distribution of fission sites and hence the approximate shape of the plutonium assembly is thereby inferred by measuring the distribution of …

The SAS-DIF3DK code couples a detailed 3-D neutron kinetics treatment with a detailed thermal hydraulics treatment. One goal of the work on SAS-DIF3DK is to produce a detailed code that will run a wide range of transients in real time. Achieving this goal will require efficient numerical methods and efficient coding, and it will probably require the use of multiple processors for larger problems. It has previously been reported that the thermal hydraulics treatment in the code achieves the required speed for typical PWR and BWR cases. This paper presents results from thermal hydraulic analysis of severe LOCA cases in a Soviet design RBMK reactor, and shows that the computing speed goals are also met in these cases.

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 …

At high pressures and temperatures, many molecular solids become unstable and transform into denser extended phases. Recently, we have discovered evidences for two novel extended phases of carbon dioxide at high pressures and temperatures: (1) an ionic form of dimeric CO,, C02+C03*- at 8-13 GPa and above 2000 K [I] and (2) a polymeric phase CO,-V above 35 GPa and 1800 K [2,3]. These extended phases can be quenched at room temperature at low pressures, from which their molecular and crystal structures have been determined. These transitions occur to soften highly repulsive intermolecular potentials via delocalization of electrons at high pressures and temperatures. Based on these and other previous results, we conjecture that three fundamental mechanisms of high-pressure chemistry are ionization, polymerization, and metallization, occurring in high-density molecular solids and fluids. [carbon dioxide, polymeric COZ, ionic CO, dimer, high-pressure chemistry, electron delocalization]

The introduction of Toyota's hybrid electric vehicle (HEV), the Prius, in Japan has generated considerable interest in HEV technology among US automotive experts. In a follow-up survey to Argonne National Laboratory's two-stage Delphi Study on electric and hybrid electric vehicles (EVs and HEVs) during 1994-1996, Argonne researchers gathered the latest opinions of automotive experts on the future ''top-selling'' HEV attributes and costs. The experts predicted that HEVs would have a spark-ignition gasoline engine as a power plant in 2005 and a fuel cell power plant by 2020. The projected 2020 fuel shares were about equal for gasoline and hydrogen, with methanol a distant third. In 2020, HEVs are predicted to have series-drive, moderate battery-alone range and cost significantly more than conventional vehicles (CVs). The HEV is projected to cost 66% more than a $20,000 CV initially and 33% more by 2020. Survey respondents view batteries as the component that contributes the most to the HEV cost increment. The mean projection for battery-alone range is 49 km in 2005, 70 km in 2010, and 92 km in 2020. Responding to a question relating to their personal vision of the most desirable HEV and its likely characteristics when introduced in the US …

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 …

Problems in extrapolation of the rate of tumor formation by strontium 89 from animal to man are addressed. Focus of this paper is on variability of latency period between different animals.

Using a diamond-anvil cell (DAC) phase transformation and room temperature Equation of State (EOS) for some actinides and lanthanides were studied to multimegabar (megabar = 100 GPa) pressures. Experimental data are compared with the theoretically predicted crystal structural changes and the pressure-volume relationships. There is a general agreement between theory and experiment for the structural changes in the lighter actinides, however in detail there are some discrepancies still. A generalized trend for the phase transformations in the lanthanides can be seen, which again has broad agreement with theory. We conclude that an accurate and robust theoretical base for predicting the phase transformations in the f-electron metals can be developed by incorporating the DAC data.

Lawrence Livermore National Laboratory� s (LLNL� s) management assigned the responsibility of conducting TSDF audits to the Waste Certification Office in August of 1994. Prior to this date, there was no mandate for LLNL to audit waste facilities, nor was there a structured program in place for conducting the audits Program development took approximately 10 months. This included writing a TSDF Audit Procedure, writing a Quality Assurance (QA) Plan, developing the required audit check lists, and using the documentation on a trial basis. A typical TSDF audit lasted one full day using three hazardous waste specialists The QA Plan is based on the quality assurance and management system requirements of DOE Order 5700.6C (Quality Assurance) and ASME NQA-1 (Quality Assurance Program Requirements for Nuclear Facilities).

This document outlines the hazard classification methodology used to determine the hazard classification of the NIF LTAB, OAB, and the support facilities on the basis of radionuclides and chemicals. The hazard classification determines the safety analysis requirements for a facility.

This report concerns the packaging configurations being tested by the U.S. DOE and its contractors, and according to U.S. DOT specification 7A Type A (DOT-7A) requirements. The objective of this Test Plan is to describe the testing for the qualification of the M-100 Container, Model M-101/7A/12/90 as a DOT-7A Type A packaging. This packaging system is designed to ship Type A solid radioactive materials, normal form, Form Number 1, Form Number 2, and Form Number 3.

This report provides a summary of the radiological surveys performed in support of near-facility environmental monitoring at the Hanford Site. The Second Quarter 1997 survey results and the status of actions required are summarized below: All of the routine environmental radiological surveys scheduled during April, May, and June 1997, were performed as planned with the exception of UN-216-E-9. This site was not surveyed as stabilization activities were in progress. The sites scheduled for the Environmental Restorations Contractor (ERC) team were switched with those identified for the third quarter as there was a conflict with vegetation management activities.

The Spent Nuclear Fuel (SNF) project technical databook provides project-approved summary tables of selected parameters and derived physical quantities, with nominal design and safety basis values. It contains the parameters necessary for a complete documentation basis of the SNF Project technical and safety baseline. The databook is presented in two volumes. Volume 1 presents K Basins SNF related information. Volume 2 (not yet available) will present selected sludge and water information, as it relates to the sludge and water removal projects. The values, within this databook, shall be used as the foundation for analyses, modeling, assumptions, or other input to SNF project safety analyses or design. All analysis and modeling using a parameter available in this databook are required to use and cite the appropriate associated value, and document any changes to those values (i.e., analysis assumptions, equipment conditions, etc). Characterization and analysis efforts are ongoing to validate, or update these values.

The USDOE Material Protection Control and Accountability Program (MPC&A) has established a Project Team with the goal of providing the Russian Electrochemical Plant (ECP) with equipment and training to enable ECP to evaluate, develop, and implement a comprehensive plan and systems for physical protection, material controls, and accountancy upgrades. The MPC&A project will provide for improvements such as risk assessments, access control upgrades, computerized MC&A, communications systems upgrades, building perimeter surveillance and intrusion detection upgrades, vault upgrades, metal and nuclear material detection upgrades, along with mass measurement and non- destructive analysis (NDA) instrumentation. This paper outlines the overall objectives of the MPC&A project at the Electrochemical Plant.

Automatic control of fine coal cleaning circuits has traditionally been limited by the lack of sensors for on-line ash analysis. Although several nuclear-based analyzers are available, none have seen widespread acceptance. This is largely due to the fact that nuclear sensors are expensive and tend to be influenced by changes in seam type and pyrite content. Recently, researchers at VPI&SU have developed an optical sensor for phosphate analysis. The sensor uses image processing technology to analyze video images of phosphate ore. It is currently being used by PCS Phosphate for off-line analysis of dry flotation concentrate. The primary advantages of optical sensors over nuclear sensors are that they are significantly cheaper, are not subject to measurement variations due to changes in high atomic number minerals, are inherently safer and require no special radiation permitting. The purpose of this work is to apply the knowledge gained in the development of an optical phosphate analyzer to the development of an on-line ash analyzer for fine coal slurries. During the past quarter, an industrially-hardened version of the video-based ash analyzer was designed and constructed. All components are now in place at the Middle Fork plant site awaiting the installation of a sample line …

A direct solver method is developed for solving Poisson`s equation numerically for the electrostatic potential {phi}(r,z) in a cylindrical region (r < R{sub wall}, 0 < z < L). The method assumes the charge density {rho}(r,z) and wall potential {phi}(r = R{sub wall}, z) are specified, and {partial_derivative}{phi}/{partial_derivative}z = 0 at the axial boundaries (z = 0, L).

A parametric study of the Spent Nuclear Fuel Project system capacity is presented. The study was completed using a commercially available software package to develop a summary level model of the major project systems. A base case, reflecting the Fiscal Year 1998 process configuration, is evaluated. Parametric evaluations are also considered, investigating the impact of higher fuel retrieval system productivity and reduced shift operations at the canister storage building on total project duration.

Ultrahigh-carbon steels (UHCSS) can achieve very high strengths in wire or rod form. These high strengths result from the mechanical work introduced during wire and rod processing. These strengths have been observed to increase with carbon content. In wire form, tensile strengths approaching 6000 MPa are predicted for UHCS containing 1. 8%C. In this paper, we will discuss the influence of processing (including rapid transformation during wire patenting) and micros ct- ure on the mechanical behavior of UHCS wire. The tensile properties of as- extruded rods are described as a function of extrusion temperature and composition. For spheroidized steels, yield and ultimate tensile strength are a function of grain size, interparticle spacing and particle size. For pearlitic steels, yield and ultimate strength were found to be functions of colony size, carbide size and plate spacing and orientation. Alloying additions (such as C, Cr, Si, Al and Co) can influence the effect of processing on these microstructural features. For spheroidized steels, fracture was found to be a function of the size of coarse carbides and of composition.

This report contains tables of the analytical results from grab samples from tank 241-AY-101. Activity levels of radionuclides are tabulated. This tanks has not been watch listed.

This test procedure was developed to determine if the 702AZ Tank Ventilation Facility system is Year 2000 Compliant. The procedure provides detailed instructions for performing the operations necessary and documenting the results. This verification procedure will document that the 702AZ Facility Systems are year 2000 compliant and will correctly meet the criteria established in this procedure.