The carbonate fuel cell promises highly efficient, cost-effective, environmentally superior power generation from pipeline natural gas, coal gas, biogas, and other gaseous and liquid fuels. ERC has been engaged in the development of this unique technology since the late 1970s, primarily focusing on the development of the Direct Fuel Cell (DFC) technology [1-6] pioneered by ERC. The DFC design incorporates the unique internal reforming feature which allows utilization of a hydrocarbon fuel directly in the fuel cell without requiring any external reforming reactor and associated heat exchange equipment. This approach provides upgrading of waste heat to chemical energy; thereby, it contributing to higher overall efficiency for conversion of fuel energy to electricity with low levels of environmental emissions. Among the internal reforming options, ERC has selected the Indirect Internal Reforming (IIR) - Direct Internal Reforming (DIR) combination as its baseline design. ERC plans to offer commercial DFC power plants in various sizes, initially focusing on the MW-scale units. The plan is to offer standardized, packaged MW-scale DFC power plants operating on natural gas or other hydrocarbon-containing fuels for commercial sale by the end of the decade. These power plants, which can be shop-fabricated and sited near the user, are ideally …

A diode-side-pumped discrete-optic E{sup 3+}:YAG laser employs pump-light coupling through a sapphire plate diffusion-bonded to the laser slab, giving reduced thermal lensing and exceptional beam quality (M{sup 2} {approx} 1.3.) The novel architecture is also applicable to other side-pumped lasers.

Fuel Cell Engineering Corporation (FCE) is in the fourth year of a DOE Cooperative Agreement Program (private-sector cost-shared) aimed at the demonstration of ERC's direct carbonate fuel cell (DFC) technology at full scale. FCE is a wholly owned subsidiary of Energy Research Corporation (ERC), which has been pursuing the development of the DFC for commercialization near the end of this decade. The DFC produces power directly from hydrocarbon fuels electrochemically, without the need for external reforming or intermediate mechanical conversion steps. As a result, the DFC has the potential to achieve very high efficiency with very low levels of environmental emissions. Modular DFC power plants, which can be shop-fabricated and sited near the user, are ideally suited for distributed generation, cogeneration, industrial, and defense applications. This project is an integral part of the ERC effort to commercialize the technology to serve these applications. Potential users of the commercial DFC power plant under development at ERC will require that the technology be demonstrated at or near the full scale of the commercial products. The objective of the Santa Clara Demonstration Project (SCDP) is to provide the first such demonstration of the technology. The approach ERC has taken in the commercialization of …

The rapid development and integration of the Internet into the mainstream of professional life provides the fuel cell industry with the opportunity to share new ideas with unprecedented capabilities. The U.S. Department of Energy's (DOE's) Morgantown Energy Technology Center (METC) has undertaken the task to maintain a Fuel Cell Forum on the Internet. Here, members can exchange ideas and information pertaining to fuel cell technologies. The purpose of this forum is to promote a better understanding of fuel cell concepts, terminology, processes, and issues relating to commercialization of fuel cell power technology. The Forum was developed by METC to provide those interested with fuel cell conference information for its current concept of exchanging ideas and information pertaining to fuel cells. Last August, the Forum expanded to an on-line and world-wide network. There are 250 members, and membership is growing at a rate of several new subscribers per week. The forum currently provides updated conference information and interactive information exchange. Forum membership is encouraged from utilities, industry, universities, and government. Because of the public nature of the internet, business sensitive, confidential, or proprietary information should not be placed on this system. The Forum is unmoderated; therefore, the views and opinions of …

There are important differences between the safety principles for nuclear weapons and for nuclear reactors. For example, a principal concern for nuclear weapons is to prevent electrical energy from reaching the nuclear package during accidents produced by crashes, fires, and other hazards, whereas the foremost concern for nuclear reactors is to maintain coolant around the core in the event of certain system failures. Not surprisingly, new methods have had to be developed to assess the risk from nuclear weapons. These include fault tree transformations that accommodate time dependencies, thermal and structural analysis techniques that are fast and unconditionally stable, and parameter sampling methods that incorporate intelligent searching. This paper provides an overview of the new methods for nuclear weapons and compares them with existing methods for nuclear reactors. It also presents a new intelligent searching process for identifying potential nuclear detonation vulnerabilities. The new searching technique runs very rapidly on a workstation and shows promise for providing an accurate assessment of potential vulnerabilities with far fewer physical response calculations than would be required using a standard Monte Carlo sampling procedure.

Typically, katabatic flows have been studied in their least complicated or idealized state. Further, these flows are generally regarded as having simple forcing and non-turbulent structure due to the strong atmospheric stability they are bedded within. Somewhat analogously, mountain waves and their effects have been mostly studied in their idealized state, i.e. for constant upstream flow and stability. Even in the numerous cases where these two atmospheric phenomena have been studied in their realistic state, seldom has their mutual interaction been considered. One exception that includes numerical modeling is Gross (1990). The express purpose of this work is to examine how each of these phenomena interact with each other in an evolving nocturnal atmosphere. This work is motivated by observations from the Atmospheric Studies in Complex Terrain (ASCOT) Program which clearly indicate non-idealized behavior in katabatic flows. Although numerous idealized simulations were also completed, discussion here focuses on the most realistic simulations of the case night 3--4 September 1993. This night was dominated by clear skies and light near surface winds. A high pressure system to the southwest of Colorado caused northwesterly flow at {approximately} 7 m s{sup {minus}1} upstream of the Rockies with a Froude number of 0.45 overnight. …

Currently, states and low-level radioactive waste (LLW) disposal site operators have no method of independently verifying the radionuclide content of packaged LLW that arrive at disposal sites for disposal. At this time, disposal sites rely on LLW generator shipping manifests and accompanying records to insure that LLW received meets the waste acceptance criteria. An independent verification system would provide a method of checking generator LLW characterization methods and help ensure that LLW disposed of at disposal facilities meets requirements. The Mobile Low-Level Waste Verification System (MLLWVS) provides the equipment, software, and methods to enable the independent verification of LLW shipping records to insure that disposal site waste acceptance criteria are being met. The MLLWVS system was developed under a cost share subcontract between WMG, Inc., and Lockheed Martin Idaho Technologies through the Department of Energy`s National Low-Level Waste Management Program at the Idaho National Engineering Laboratory (INEL).

Idealized analytical investigations of katabatic slope flows have usually sought to simplify the analysis by either assuming a particular force balance amenable to analytical solution or using integral (or bulk) models. In each case, steady state conditions are evaluated, with occasional exception. Historically, the modeling of idealized katabatic flows has focused analysis of model time where steady state conditions have been achieved. To investigate the true dynamics of evolving undisturbed katabatic flow, the Regional Atmospheric Modeling System (RAMS) is used. As described in Pielke et al (1992) RAMS is a prognostic numerical model that contains the three-dimensional primitive equations in terrain-following, non- hydrostatic, compressible form. In addition to standard variables, RAMS was configured to output the various components of the governing equations with high temporal resolution. Each of the simulations used idealized 2000m high mountain topography of a given slope (1{degree}, 2.5{degrees},5{degrees}, or 10{degrees}) on either side of the peak. In the 3-d simulations this mountain becomes an infinite north-south ridge (cyclic boundary conditions in the N-S direction). Vertical grid spacing was set to 20m for the first 500m {delta}z increases to a maximum of 400 m over 72 grid points to 10.5 km. Horizontal grid spacing was 500 m …

The Department of Energy (DOE) is preparing for disposal operations at the Waste Isolation Pilot Plant (WIPP) in 1998. WIPP is a deep geological repository designed for the safe and efficient disposal of transuranic (TRU) wastes. The Waste Acceptance Criteria (WAC) for WIPP were initially developed by a DOE steering committee in 1980. Revision 5 reflects the latest negotiations and permit requirements from the Environmental Protection Agency (EPA), the State of New Mexico Environment Department (NMED), and the Nuclear Regulatory Commission (NRC). The regulatory requirements are combined with the requirements derived from the WIPP safety analysis performed for disposal operations and the original criteria established for safe waste handling operations. The WIPP WAC provides a comprehensive overview of the requirements and basis for developing waste acceptance criteria to meet today`s rules and regulations for transportation and disposal of TRU wastes. The authors believe that it is a comprehensive criteria and a guidance manual for generator/storage sites who must characterize and certify TRU waste for disposal at WIPP. It also provides valuable insight to future projects that may develop their own waste acceptance criteria. The WIPP WAC presents the requirements from the following sources: 1) Resource Conservation and Recovery Act (RCRA) …

The Cassini spacecraft is a deep space probe whose mission is to explore the planet Saturn and its moons. Since the spacecraft`s electrical requirements will be supplied by radioisotope thermoelectric generators (RTGs), the spacecraft designers and mission planners must assure that potential accidents involving the spacecraft do not pose significant human risk. The Cassini risk analysis team is seeking to perform a quantitative uncertainty analysis as a part of the overall mission risk assessment program. This paper describes the uncertainty analysis methodology to be used for the Cassini mission and compares it to the methods that were originally developed for evaluation of commercial nuclear power reactors.

In November 1988, the US Nuclear Regulatory Commission (NRC) issued Generic Letter 88-20 requesting that all licensees perform an individual Plant Examination (IPE) to identify any plant-specific vulnerability to severe accidents and report the results to the Commission. This paper provides perspectives gained from reviewing 75 Individual Plant Examination (IPE) submittals covering 108 nuclear power plant units. Variability both within and among reactor types is examined to provide perspectives regarding plant-specific design and operational features, and modeling assumptions that play a significant role in the estimates of core damage frequencies in the IPEs.

Linear alkylbenzenes (phenylalkanes) represent an important class of molecular compounds used widely in today`s society as building blocks for detergent manufacture. Evidence is presented to support the proposition in that phenylalkanes in some Australian crude oils and sediments are of geochemical origin rather than resulting from contamination from byproducts of the petrochemical synthesis of surfactants. Evidence presented shows: (1) an unexposed sediment core was found to contain phenylalkanes; (2) the molecular weight range of phenylalkanes in sediments and crude oils is usually wider than that found in surfactants, extending in some cases beyond C{sub 35}; and (3) phenylalkanes were found in the neutral lipid extract of extant {ital Thermoplasma} bacteria. {ital Thermoplasma acidophilum} is an obligate acidiphilic (pH 2) and thermophilic (60{degrees}C), cell wall-less archaeobacterium originally isolated from self-heating coal refuse piles enriched in pyritic materials.

This paper describes an evolutionary development process that will lead to spent fuel measurements that directly measure fissile reactivity. First, the Fork measurement system has been used to verify the burnup of pressurized water reactor (PWR) spent-fuel assemblies at U.S. nuclear utilities. Fork measurements have demonstrated the utility of the passive Fork system to verify reactor records with a single 100-second measurement on each assembly. Second, an Advanced Fork system incorporating collimated gamma-ray spectroscopy has been designed to permit advanced calibration techniques that are independent of reactor burnup records and to allow rapid axial scanning of spent fuel assemblies. Third, an Active Fork system incorporating a neutron source to interrogate spent fuel is proposed to provide the capability to measure fissile reactivity, when compared to measurements on fresh fuel assemblies of the same design. The Advanced and Active Fork systems have wide applicability to spent fuel verification for PWR, boiling water reactor (BWR), and U.S. Department of Energy (DOE) spent fuel.

This paper describes a groundwater modeling study of waste disposal concepts using grouted waste forms. The focus of the study is on the effects of clay caps and concrete vaults on contaminant migration. The authors modeled three waste disposal scenarios: (1) Grouted waste was solidified in an earthen trench and covered with soil, there was no vault and no cap; (2) grouted waste was solidified in an earthen trench, the entire waste disposal facility was then closed under a clay cap; (3) grouted waste was solidified in a concrete vault and protected by the same closure as in 2. Because of the huge contrast in hydraulic conductivities and highly non-linear multi-phase flow characteristics, these waste disposal concepts presented a difficult problem for numerical simulation. Advanced fluid flow and contaminant transport codes were used to solve the problem. Among the codes tested, ECLIPSE out-performed other codes in speed, accuracy (smaller material balance errors) and capability in handling sophisticated scenarios. The authors used nitrate as a tracer for the simulation. Nitrate does not absorb in the solid phase and does not decay. As a result, predicted release rate based on nitrate is conservative. They also assumed that the facility is intact for …

The Explosive Components Facility (ECF) is a major, low-hazard, non-nuclear, research and development facility of the Sandia National Laboratories/Albuquerque (SNL). Sandia Corporation, a subsidiary of Lockheed-Martin, operates this designated User Facility for the Department of Energy (DOE). The ECF consolidates many SNL energetic-materials activities and provides a unique combination of explosive-technologies, neutronic-components, batteries, and weapons-evaluation capabilities. This paper describes the project objectives, the basic building features, programmatic capabilities, and the processes used to beneficially occupy and assess readiness to operate.

The MELCOR Accident Consequence Code System (MACCS), publicly distributed since 1987, was developed to estimate the potential impacts to the surrounding public of severe accidents at nuclear power plants. The principal phenomena considered in MACCS are atmospheric transport and deposition under time-variant meteorology, short-term and long-term mitigative actions and exposure pathways, deterministic and stochastic health effects, and economic costs of mitigative actions. At this time, no other publicly available code in the US offers all these capabilities. MACCS2 represents a major enhancement of the capabilities of its predecessor MACCS. MACCS2 was developed as a general-purpose analytical tool applicable to diverse reactor and nonreactor Department of Energy (DOE) facilities. The MACCS2 package includes three primary enhancements: (1) a more flexible emergency response model, (2) an expanded library of radionuclides, and (3) a semidynamic food-chain model. The new code features allow detailed evaluations of risks to workers at nearby facilities on large DOE reservations and allow the user to assess the potential impacts of over 700 radionuclides that cannot be considered with MACCS.

In a recent review it is said that free-surface flows ``represent some of the difficult remaining challenges in computational fluid dynamics``. There has been progress with the development of new approaches to treating interfaces, such as the level-set method and the improvement of older methods such as the VOF method. A common theme of many of the new developments has been the regularization of discontinuities at the interface. One example of this approach is the continuum surface force (CSF) formulation for surface tension, which replaces the surface stress given by Laplace`s equation by an equivalent volume force. Here, we describe how CSF might be made more useful. Specifically, we consider a derivation of the CSF equations from a minimization of surface energy as outlined by Jacqmin. This reformulation suggests that if one eliminates the computation of curvature in terms of a unit normal vector, parasitic currents may be eliminated For this reformulation to work, it is necessary that transition region thickness be controlled. Various means for this, in addition to the one discussed by Jacqmin are discussed.

The undulator beamline at the storage ring PETRA of the Hamburger Synchrotronstrahlungslabor HASYLAB delivers hard x-ray photons usable up to 300 keV. The total power of the beam is now up to 7.5 kW with closed gap and 60 mA stored particle beam. After a planned upgrade of the undulator, the power can increase to about 15 kW. The vertical white beam slit for the PETRA undulator beamline is located at about 105 m from the source. The worst case for the slit is when all the power is absorbed in one part of the slit system, which the slits must survive. This paper presents the results from parameter optimization in the worst case. The goal of the optimization is to minimize the maximum temperature of the slits. The geometrical parameters are the cooling hole size, its location from the surface, and the distance between holes. The worst case is found by moving the x-ray beam to all the possible locations. The maximum temperature of an optimized slit that has a two degree angle with the beam is about 192 degrees Celsius. The corresponding thermal stress in the slit is very low. The analysis assumptions, modeling, results, discussion, and conclusion …

This paper describes the competitiveness of Japan in the telecommunications technologies and manufacturing of electronic equipment.

Recently, there has been a resurgence of interest in nuclear medicine therapeutic procedures. Using unsealed sources for therapy is not a new concept; it has been around since the beginnings of nuclear medicine. Treatment of thyroid disorders with radioiodine is a classic example. The availability of radionuclides with suitable therapeutic properties for specific applications, as well as methods for their selective targeting to diseased tissue have, however, remained the main obstacles for therapy to assume a more widespread role in nuclear medicine. Nonetheless, a number of new techniques that have recently emerged, (e.g., tumor therapy with radiolabeled monoclonal antibodies, treatment of metastatic bone pain, etc.) appear to have provided a substantial impetus to research on production of new therapeutic radionuclides. Although there are a number of new therapeutic approaches requiring specific radionuclides, only selected broad areas will be used as examples in this article.

Positron beam position measurement for the Advanced Photon Source (APS) linac beam is affected by the presence of electrons that are also captured and accelerated along with the positrons. This paper presents a method of measuring positron position in a beam consisting of alternating bunches of positrons and electrons. The method is based on Fourier analysis of a stripline signal at the bunching and first harmonic frequencies. In the presence of a mixed species beam, a certain linear combination of bunching and first harmonic signals depends only on the position and charge of one specie of particle. A formula is derived for the stripline signal at all harmonics of the bunching frequency and is used to compute expected signal power at the bunching and first harmonic frequencies for typical electron and positron bunch charges. The stripline is calibrated by measuring the signal power content at the bunching and first harmonic frequencies for a single species beam. A circuit is presented that will be used with an APS positron linac stripline beam position monitor to detect the bunching and first harmonic signals for a beam of positrons and electrons.

In many important cryogenic applications the use of liquid cryogens for system cooling are either not feasible or are unsuitable. In such cases a cryogenic refrigeration system or multi stage cryocooler must be employed to provide the necessary cooling. To shorten cooldown time for such a system, especially if the thermal mass is large, a thermal shunt directly connecting the first stage of the cryocooler to the load during cooldown is desirable. This thermal shunt allows effective utilization of the greater cooling power available from the first stage of the cryocooler early in the cooldown. Upon reaching operating temperature, the thermal shunt must exhibit a high resistance to thermally isolate the first stage of the cryocooler from the load. Heat pipes are well suited to achieve these objectives. The Advanced Lightweight Influence Sweep System (ALISS), under development by the U.S. Navy for shallow water magnetic mine countermeasures, employs a large, conductively cooled, superconducting magnet that must be cooled from 300 to 4.2 K. Cryogenic heat pipes acting as cryocooler thermal shunts are used to shorten the cooldown time. Ethane, nitrogen and oxygen were evaluated as possible working fluids. A thermal model of the ALISS was developed to evaluate the cooldown …

The purpose of the Data Visualization Project at Sandia Labs is to prototype and evaluate new approaches to the presentation of data for CTBT monitoring applications. The great amount of data expected to be available, and the complex interrelationships in that data, make this a promising area for scientific data visualization techniques. We are developing a powerful and flexible prototyping environment with which to explore these possibilities. A user-friendly graphical user interface (GUI) should be an integral part of any data visualization tools developed. The GUI is necessary to select which data to visualize, and to modify and explore the displays that are the result of data visualization. Using our prototyping environment, we have produced data visualization displays of various kinds of data and have also experimented with different GUIs for controlling the visualization process. We present here an overview of that work, including promising results, lessons learned, and work in progress. To better understand what is needed, we have identified several data processing/analysis scenarios which we think will be important in CTBT monitoring. These scenarios help us identify what types of information we should display (together or in sequence), and help us focus on isolating the underlying goals. Each …

Initial commissionings of the Advanced Photon Source (APS) 7 GeV storage ring and the installed synchrotron radiation monitors have been done. Early studies involved single bunch measurements on the transverse beam sizes ({delta}{sub x} {approx} 150 {mu}m, {delta}{sub y} {approx} 50 {mu}m) and longitudinal profile ({delta}{sub {tau}} {approx} 25 to 50 ps) as a function of stored beam current (0.2 to 7.7 mA). Additionally, the vertical head-tail instability was purposely induced by decreasing sextupole fields and graphically displayed by the use of a dual sweep streak camera. These measurements were primarily base on optical synchrotron radiation (OSR). More recent measurements have involved multibunch studies with beam currents up to 100 mA. Progress on the x-ray synchrotron radiation (XSR) imaging station will also be briefly discussed.