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Creators/Authors contains: "Johnson, Jack S."

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  1. Abstract. Observations over the last decade have demonstrated that theatmosphere contains potentially hundreds of compounds that can react withsulfuric acid to nucleate stable aerosol particles. Consequently, modelingatmospheric nucleation requires detailed knowledge of nucleation reactionkinetics and spatially and temporally resolved measurements of numerousprecursor compounds. This study introduces the Nucleation Potential Model(NPM), a novel nucleation model that dramatically simplifies the diversereactions between sulfuric acid and any combination of precursor gases. The NPMpredicts 1 nm nucleation rates from only two measurable gas concentrations,regardless of whether all precursor gases are known. The NPM describes sulfuricacid nucleating with a parameterized base compound at an effective baseconcentration, [Beff]. [Beff] captures the ability of a compoundor mixture to form stable clusters with sulfuric acid and is estimated frommeasured 1 nm particle concentrations. The NPM is applied to experimental andfield observations of sulfuric acid nucleation to demonstrate how[Beff] varies for different stabilizing compounds, mixtures, andsampling locations. Analysis of previous field observations shows distinctdifferences in [Beff] between locations that follow the emissionsources and stabilizing compound concentrations for that region. Overall,the NPM allows researchers to easily model nucleation across diverseenvironments and estimate the concentration of non-sulfuric acid precursorsusing a condensation particle counter. 
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