The technical basis for air pathway assessment of resuspended radioactive aerosols: LLNL experiences at seven sites around the world (open access)

The technical basis for air pathway assessment of resuspended radioactive aerosols: LLNL experiences at seven sites around the world

There is a large uncertainty in quantifying the inhalation pathway and the aerosol emission rate in human health assessments of radioactive-contamination sites. The need for site-specific assessments led to formation of our team of specialists at LLNL, who have participated in numerous field campaigns around the world. Our goal was to obtain all the information necessary for determining potential human exposures and to estimate source terms for turbulent transport of the emissions during both normal and disturbed soil conditions. That is, measurements were made of the key variables to quantify the suspended aerosols at the actual contamination sites, but different scenarios for habitation, site management, and site cleanup were included. The most notable locations of these site-investigations were the Marshall Islands (Bikini, Enewetak, and Rongelap), Nevada Test Site (GMX, Little Feller, Palanquin, and Plutonium Valley), Tonopah (Nevada--site of Roller Coaster), Savannah River Lab (South Carolina--H-Area site), Johnston Island (cleanup of rocket-impact site), Chernobyl (Ukraine--grass field end sandy beach sites near Nuclear Power Plant Unit 4), and Palomares (Spain--site of aircraft accident). This discussion will review the variables quantified, methods developed, general results, uncertainty of estimations, and recommendations for future research that are a result of our experience in these field …
Date: September 1, 1993
Creator: Shinn, J. H.
System: The UNT Digital Library
Evaluation of the Atmospheric Release Advisory Capability emergency response model for explosive sources (open access)

Evaluation of the Atmospheric Release Advisory Capability emergency response model for explosive sources

The Atmospheric Release Advisory Capability (ARAC) at the Lawrence Livermore National Laboratory (LLNL) uses a modeling system to calculate the impact of accidental radiological or toxic releases to the atmosphere anywhere in the world. Operated for the US Departments of Energy and Defense, ARAC has responded to over 60 incidents in the past 18 years, and conducts over 100 exercises each year. Explosions are one of the most common mechanisms by which toxic particulates are injected into the atmosphere during accidents. Automated algorithms with default assumptions have been developed to estimate the source geometry and the amount of toxic material aerosolized. The paper examines the sensitivity of ARAC`s dispersion model to the range of input values for explosive sources, and analyzes the model`s accuracy using two field measurement programs.
Date: October 7, 1993
Creator: Baskett, R. L.; Freis, R. P. & Nasstrom, J. S.
System: The UNT Digital Library
Basis for the power supply reliability study of the 1 MW neutron source (open access)

Basis for the power supply reliability study of the 1 MW neutron source

The Intense Pulsed Neutron Source (IPNS) upgrade to 1 MW requires new power supply designs. This paper describes the tools and the methodology needed to assess the reliability of the power supplies. Both the design and operation of the power supplies in the synchrotron will be taken into account. To develop a reliability budget, the experiments to be conducted with this accelerator are reviewed, and data is collected on the number and duration of interruptions possible before an experiment is required to start over. Once the budget is established, several accelerators of this type will be examined. The budget is allocated to the different accelerator systems based on their operating experience. The accelerator data is usually in terms of machine availability and system down time. It takes into account mean time to failure (MTTF), time to diagnose, time to repair or replace the failed components, and time to get the machine back online. These estimated times are used as baselines for the design. Even though we are in the early stage of design, available data can be analyzed to estimate the MTTF for the power supplies.
Date: July 1, 1993
Creator: McGhee, D. G. & Fathizadeh, M.
System: The UNT Digital Library
Ninth target fabrication specialists` meeting: Proceedings (open access)

Ninth target fabrication specialists` meeting: Proceedings

This report contains a collection of viewgraphs and short papers on target fabrication for inertial confinement purposes.
Date: December 31, 1993
Creator: unknown
System: The UNT Digital Library
Understanding Superconducting Magnetic Energy Storage (SMES) technology, applications, and economics, for end-use workshop (open access)

Understanding Superconducting Magnetic Energy Storage (SMES) technology, applications, and economics, for end-use workshop

The overall objective of this project was to determine the state-of-the-art and to what extent existing SMES is a viable option in meeting the needs of utilities and their customers for improving electric service power quality. By defining and analyzing SMES electrical/mechanical performance characteristics, and comparing SMES application benefits with competitive stored energy systems, industry will be able to determine SMES unique applications and potential market penetration. Building on this information base, it would also be possible to evaluate the impact of high temperature superconductors (77 K and 20-35 K) on SMES technology applications. The authors of this report constructed a network of industry contacts and research consultants that were used to collect, update, and analyze ongoing SMES R&D and marketing activities in industries, utilities, and equipment manufacturers. These key resources were utilized to assemble performance characteristics on existing SMES, battery, capacitor, flywheel, and high temperature superconductor (HTS) stored energy technologies. From this information, preliminary stored energy system comparisons were accomplished. In this way, the electric load needs would be readily comparable to the potential solutions and applications offered by each aforementioned energy storage technology.
Date: June 1, 1993
Creator: Ferraro, R. J. & McConnell, B. W.
System: The UNT Digital Library
Ninth International Workshop on Plant Membrane Biology (open access)

Ninth International Workshop on Plant Membrane Biology

This report is a compilation of abstracts from papers which were discussed at a workshop on plant membrane biology. Topics include: plasma membrane ATP-ases; plant-environment interactions, membrane receptors; signal transduction; ion channel physiology; biophysics and molecular biology; vaculor H+ pumps; sugar carriers; membrane transport; and cellular structure and function.
Date: December 31, 1993
Creator: unknown
System: The UNT Digital Library