The calculation of downwind concentrations from non-traditional sources, such as explosions, provides unique challenges to dispersion models. The US Department of Energy has assigned the Atmospheric Release Advisory Capability (ARAC) at the Lawrence Livermore National Laboratory (LLNL) the task of estimating the impact of accidental radiological releases to the atmosphere anywhere in the world. Our experience includes responses to over 25 incidents in the past 16 years, and about 150 exercises a year. Examples of responses to explosive accidents include the 1980 Titan 2 missile fuel explosion near Damascus, Arkansas and the hydrogen gas explosion in the 1986 Chernobyl nuclear power plant accident. Based on judgment and experience, we frequently estimate the source geometry and the amount of toxic material aerosolized as well as its particle size distribution. To expedite our real-time response, we developed some automated algorithms and default assumptions about several potential sources. It is useful to know how well these algorithms perform against real-world measurements and how sensitive our dispersion model is to the potential range of input values. In this paper we present the algorithms we use to simulate explosive events, compare these methods with limited field data measurements, and analyze their sensitivity to input parameters. …

We were able to predict acid concentration to {plus_minus}0.08M HNO{sub 3}. In the presence of Al{sup 3} interference, the prediction dropped to {plus_minus}0.29 mols/liter over the range 0 to 9M HNO{sub 3}. Temperature affects the prediction of acid adversely and would have to be modelled out or the sample cell thermostated prior to using this method. 10 refs, 12 figs.(DLC)

We were able to predict acid concentration to {plus minus}0.08M HNO{sub 3}. In the presence of Al{sup 3} interference, the prediction dropped to {plus minus}0.29 mols/liter over the range 0 to 9M HNO{sub 3}. Temperature affects the prediction of acid adversely and would have to be modelled out or the sample cell thermostated prior to using this method. 10 refs, 12 figs.(DLC)

A resonantly photo-pumped x-ray laser is formed of a vanadium and titanium foil combination that is driven by two beams of intense line focused optical laser radiation. Ground state neon-like titanium ions are resonantly photo-pumped by line emission from fluorine-like vanadium ions.