The concept of a disturbed zone surrounding the mined openings of a potential geologic repository for high-level radioactive waste was introduced by the US Nuclear Regulatory Commission (NRC) as a region to be excluded for determining groundwater travel time to the accessible environment, but to be included for determining the impact of underground construction and radioactive decay heat on groundwater movement and radionuclide transport for total system performance analysis. This paper explores both the regulatory and technical necessity for characterizing and modeling a larger region -- the altered zone -- within which the temperature is increased significantly by heat from the high-level waste. Particular attention is given to addressing the effects of heterogeneity on groundwater flux and travel time, showing how these effects might be modeled simply on a macroscopic scale, and outlining its parameters. The effect of uncertainty in the parameter values on the performance of a potential repository can then be easily handled by probabilistic analysis.

Fifty nanosecond pulses of visible light have been used to produce hard, hydrogen-free diamond-like-carbon (DLC) films at irradiances between 5 x 10{sup 8} and 5 x 10{sup 10} W/cm{sup 2} The films were characterized by a number of techniques including: Raman spectroscopy, Electron Energy Loss Spectroscopy (EELS), atomic force microscopy, and spectroscopic ellipsometry. The cost for manufacturing DLC with high average power, high-pulse repetition frequency, visible light is low enough to compete with other diamond thin film production methods.

The basic mechanisms of metastable phase formation produced under highly non-equilibrium thermodynamic conditions within high-energy particle tracks are investigated. In particular, the possible formation of diamond by heavy-ion irradiation of graphite at ambient temperature is examined. This work was motivated, in part, by earlier studies which discovered nanometer-grain polycrystalline diamond aggregates of submicron-size in uranium-rich carbonaceous mineral assemblages of Precambrian age. It was proposed that the radioactive decay of uranium formed diamond in the fission particle tracks produced in the carbonaceous minerals. To test the hypothesis that nanodiamonds can form by ion irradiation, fine-grain polycrystalline graphite sheets were irradiated with 400 MeV Kr ions. The ion irradiated graphite (and unirradiated graphite control) were then subjected to acid dissolution treatments to remove the graphite and isolate any diamonds that were produced. The acid residues were then characterized by analytical and high-resolution transmission electron microscopy. The acid residues of the ion-irradiated graphite were found to contain ppm concentrations of nanodiamonds, suggesting that ion irradiation of bulk graphite at ambient temperature can produce diamond.

An excited minimum, or false vacuum, gives rise to a highly elongated superdeformed (SD) nucleus. A brief review of superdeformation is given, with emphasis on the tunneling from the false to the true vacuum, which occurs in the feeding and decay of SD bands. During the feeding process the tunneling is between hot states, while in the decay it is from a cold to a hot state. The {gamma} spectra connecting SD and normal-deformed (ND) states provide information on several physics issues: the decay mechanism; the spin/parity quantum numbers, energies and microscopic structures of SD bands; the origin of identical SD bands; the quenching of pairing with excitation energy; and the chaoticity of excited ND states at 2.5-5 MeV. Other examples of tunneling in nuclei, which are briefly described, include the possible role of tunneling in {Delta}I = 4 bifurcation in SD bands, sub-barrier fusion and proton emitters.

The existing superconducting linac ATLAS is in many respects an ideal secondary beam accelerator for an ISOL (Isotope separator on-line) type radioactive beam facility. Such a facility would require the addition of two major accelerator elements: a low charge state injector for the existing heavy ion linac, and a primary beam accelerator providing 220 MV of acceleration for protons and light ions. Development work for both of these elements, including the option of superconducting cavities for the primary beam accelerator is discussed.

This report presents the results of groundwater monitoring and summarizes current interpretations of conditions influencing groundwater quality and flow in the 100-K Area. The interpretations build on previous work, and statisticzd evaluations of contaminant concentrations were ptiormed for the period July 1996 through April 1998. No new basin leaks are indicated by data from this period. Tritium from a 1993 leak in the KE Basin has been detected in groundwater and appears to be dissi- pating. Tritium and strontium-90 from inactive injection wells/drain fields are still evident near the KW and KE Basins. These contaminants have increased as a result of infiltration of surface water or a higher- " than-average water table. Inactive condensate cribs near the KW and KE Basins resulted in very high tritium and carbon-14 activities in some wells. Recent tritium decreases are attributed to changes in groundwater-flow direction caused by the higher-than-average river stage in 1996-1998, which caused the contaminant plumes to move away from the monitoring wells. Results of the groundwater-monitoring program were used to identi~ and correct factors that may contribute to contaminant increases. For example, some sources of surface-water infiltration have been diverted. Additional work to reduce infiltration through contaminated sediments is planned …

Amorphous carbon films approximately 20 nm thick are used throughout the computer industry as protective coatings on magnetic storage disks. As storage densities increase, the role of the overcoat becomes increasingly important because of smaller spacings between the recording head and the spinning disk. Furthermore, future-generation disks call for an overcoat thickness of 5 nm or less. These small length scales and the high speed of the spinning disk (10-30 m/s) suggest that a molecular dynamics (MD) model might provide useful insight into friction and wear mechanisms when the head and disk make contact. One of the necessary inputs required to carry out such an MD model is a specification of the position of all the atoms in the simulation, i.e. a detailed model of the material microstructure. Such a detailed understanding of the microstructure of amorphous carbon overcoats does not presently exist. Neutron and electron diffraction studies demonstrate that the material is amorphous. Previous classical MD simulations yield pair distribution functions in qualitative agreement with the diffraction studies, but they all differ in detail. More recent, quantum-mechanical tight-binding MD (TBMD) studies give a better description of the interatomic interactions and the chemical hybridization (sp{sup 2}-graphite-like versus sp{sup 3}-diamond-like). However, …

This thesis comprises three parts: Electrocatalysis of anodic oxygen-transfer reactions: aliphatic amines at mixed Ag-Pb oxide thin-film electrodes; oxidation of ammonia at anodized Ag-Pb eutectic alloy electrodes; and temperature effects on oxidation of ethylamine, alanine, and aquated ammonia.

With the end of the Cold War, the world faces for the first time the need to dismantle vast numbers of ``excess`` nuclear weapons and dispose of the fissile materials they contain, together with fissile residues in the weapons production complex left over from the production of these weapons. If recently agreed US and Russian reductions are fully implemented, tens of thousands of nuclear weapons, containing a hundred tons or more of plutonium and hundreds of tonnes* of highly enriched uranium (HEU), will no longer be needed worldwide for military purposes. These two materials are the essential ingredients of nuclear weapons, and limits on access to them are the primary technical barrier to prospective proliferants who might desire to acquire a nuclear weapons capability. Theoretically, several kilograms of plutonium, or several times that amount of HEU, is sufficient to make a nuclear explosive device. Therefore, these materials will continue to be a potential threat to humanity for as long as they exist.

This monthly reports describes progress in three projects, namely (1) Thermochemical Production of Hydrogen from Wet Biomass, (2) Photoelectrochemical Production, and (3) Photobiological Production.

These lectures are an attempt to a pedagogical introduction into the elementary concepts of chiral symmetry in nuclear physics. Effective chiral models such as the linear and nonlinear sigma model will be discussed as well as the essential ideas of chiral perturbation theory. Some applications to the physics of ultrarelativistic heavy ion collisions will be presented.

An experimental investigation of soft x-ray production resulting from the interaction of intense near infra-red laser radiation with gases is presented in this thesis. Specifically, soft x-ray generation through high order harmonic generation or exploiting intense inverse bremsstrahlung heating is examined. Most of these studies are conducted with femtosecond, terawatt class Cr:LiSrAlF{sub 6} (LiSAF) laser, though results derived from studies with other laser systems are presented as well. The majority of this work is devoted to experimental investigations, however, theoretical and computational models are developed to interpret the data. These studies are motivated by the possibility of utilizing the physics of intense laser/matter interactions as a potential compact source of bright x-rays. Consequently, the thrust of many of the experiments conducted is aimed at characterizing the x-rays produced for possible use in applications. In general, the studies of this manuscript fall into three categories. First, a unique 130 fs, 8 TW laser that is based on chirped pulse amplification, is described, and its performance is evaluated. The generation of x-rays through high order harmonics is then discussed with emphasis on characterizing and optimizing harmonic generation. Finally, the generation of strong, incoherent x-ray radiation by the intense irradiation of large (>1,000 …

High integrity/high consequence systems must be safe and reliable; hence it is only logical that both software safety and software reliability cases should be developed. Risk assessments in safety cases evaluate the severity of the consequences of a hazard and the likelihood of it occurring. The likelihood is directly related to system and software reliability predictions. Software reliability cases, as promoted by SAE JA 1002 and 1003, provide a practical approach to bridge the gap between hardware reliability, software reliability, and system safety and reliability by using a common methodology and information structure. They also facilitate early insight into whether or not a project is on track for meeting stated safety and reliability goals, while facilitating an informed assessment by regulatory and/or contractual authorities.

The Boeing Company's Dish Engine Critical Component (DECC) project started in April of 1998. It is a continuation of a solar energy program started by McDonnell Douglas (now Boeing) and United Stirling of Sweden in the mid 1980s. The overall objectives, schedule, and status of this project are presented in this paper. The hardware test configuration, hardware background, operation, and test plans are also discussed. A summary is given of the test data, which includes the daily power performance, generated energy, working-gas usage, mirror reflectivity, solar insolation, on-sun track time, generating time, and system availability. The system performance based upon the present test data is compared to test data from the 1984/88 McDonnell Douglas/United Stirling AB/Southem California Edison test program. The test data shows that the present power, energy, and mirror performance is comparable to when the hardware was first manufactured 14 years ago.

Using surface micromachined samples, we demonstrate the accurate measurement of cantilever beam adhesion by using test structures which are adhered over long attachment lengths. We show that this configuration has a deep energy well, such that a fracture equilibrium is easily reached. When compared to the commonly used method of determining the shortest attached beam, the present method is much less sensitive to variations in surface topography or to details of capillary drying.

This document is one of the tools used to develop and control the mission work as depicted in the included figure. This Technical Baseline Summary Description document is the top-level tool for management of the Technical Baseline for waste storage operations.

This document is a plan presenting the objectives, organization, and management and technical approaches for the Waste Feed Delivery (WFD) Program. This WFD Plan focuses on the Tank Waste Remediation System (TWRS) Project`s Waste Retrieval and Disposal Mission.

The project`s aim is to complete development of the Radial Cutting Torch, a pyrotechnic cutter, for use in all downhole tubular cutting operations in the petroleum industry. Project objectives are to redesign and pressure test nozzle seals to increase product quality, reliability, and manufacturability; improve the mechanical anchor to increase its temperature tolerance and its ability to function in a wider variety of wellbore fluids; and redesign and pressure test the RCT nozzle for operation at pressures from 10 to 20 ksi. The proposal work statement is included in the statement of work for the grant via this reference.

This system plan presents the objectives, organization, and management and technical approaches for the Infrastructure Program. This Infrastructure Plan focuses on the Tank Waste Remediation System (TWRS) Project`s Retrieval and Disposal Mission.

This revision of the Project W-314 Upgrade Scope Summary Report (USSR) represents a refinement of the project scope and supporting justification from which the Conceptual Design Report (CDR) was developed. It defines the actual upgrades and provides traceability to the requirement or driver for the activity.

Over the past decade, Sandia National Laboratories has been involved in the development of receivers to transfer energy from the focus of a parabolic dish concentrator to the heater tubes of a Stirling engine. Through the isothermal evaporation and condensation of sodium. a heat-pipe receiver can efficiently transfer energy to an engine's working fluid and compensate for irregularities in the flux distribution that is delivered by the concentrator. The operation of the heat pipe is completely passive because the liquid sodium is distributed over the solar-heated surface by capillary pumping provided by a wick structure. Tests have shown that using a heat pipe can boost the system performance by twenty percent when compared to directly illuminating the engine heater tubes. Designing heat pipe solar receivers has presented several challenges. The relatively large area ({approximately}0.2 m{sup 2}) of the receiver surface makes it difficult to design a wick that can continuously provide liquid sodium to all regions of the heated surface. Selecting a wick structure with smaller pores will improve capillary pumping capabilities of the wick, but the small pores will restrict the flow of liquid and generate high pressure drops. Selecting a wick that is comprised of very tine filaments …

Energy Conversions Incorporated has made substantial progress on the EMD-710 dual-fuel test cell in the first quarter of the project. The project is on schedule and has not met with any major roadblocks that would derail the planned timetable. Please note that much of the work done started before the funding arrived, and therefore those items are not included in the financial expenditures for the quarter.

This task plan is a documented agreement between Nuclear Safety and Licensing and the Process Development group within the Waste Feed Delivery organization. The purpose of this task plan is to identify the scope of work, tasks and deliverables, responsibilities, manpower, and schedules associated with an authorization basis amendment as a result of the Waste Feed Waste Delivery Program, Project W-211, and Project W-TBD.

The Waste Remediation System Facilities Configuration Management Integration group has requested development of a system to help resolve many of the difficulties associated with management of master equipment list information. This project has been identified as Master Equipment List (MEL) database system. Further definition is contained in the system requirements specification (SRS).