Sample records for dynamics aerosol chemistry

  1. Heterogeneous Chemistry: Understanding Aerosol/Oxidant Interactions

    SciTech Connect (OSTI)

    Joyce E. Penner

    2005-03-14T23:59:59.000Z

    Global radiative forcing of nitrate and ammonium aerosols has mostly been estimated from aerosol concentrations calculated at thermodynamic equilibrium or using approximate treatments for their uptake by aerosols. In this study, a more accurate hybrid dynamical approach (DYN) was used to simulate the uptake of nitrate and ammonium by aerosols and the interaction with tropospheric reactive nitrogen chemistry in a three-dimensional global aerosol and chemistry model, IMPACT, which also treats sulfate, sea salt and mineral dust aerosol. 43% of the global annual average nitrate aerosol burden, 0.16 TgN, and 92% of the global annual average ammonium aerosol burden, 0.29 TgN, exist in the fine mode (D<1.25 {micro}m) that scatters most efficiently. Results from an equilibrium calculation differ significantly from those of DYN since the fraction of fine-mode nitrate to total nitrate (gas plus aerosol) is 9.8%, compared to 13% in DYN. Our results suggest that the estimates of aerosol forcing from equilibrium concentrations will be underestimated. We also show that two common approaches used to treat nitrate and ammonium in aerosol in global models, including the first-order gas-to-particle approximation based on uptake coefficients (UPTAKE) and a hybrid method that combines the former with an equilibrium model (HYB), significantly overpredict the nitrate uptake by aerosols especially that by coarse particles, resulting in total nitrate aerosol burdens higher than that in DYN by +106% and +47%, respectively. Thus, nitrate aerosol in the coarse mode calculated by HYB is 0.18 Tg N, a factor of 2 more than that in DYN (0.086 Tg N). Excessive formation of the coarse-mode nitrate in HYB leads to near surface nitrate concentrations in the fine mode lower than that in DYN by up to 50% over continents. In addition, near-surface HNO{sub 3} and NO{sub x} concentrations are underpredicted by HYB by up to 90% and 5%, respectively. UPTAKE overpredicts the NO{sub x} burden by 56% and near-surface NO{sub x} concentrations by a factor of 2-5. These results suggest the importance of using the more accurate hybrid dynamical method in the estimates of both aerosol forcing and tropospheric ozone chemistry.

  2. Molecular Chemistry of Organic Aerosols Through the Application...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Chemistry of Organic Aerosols Through the Application of High Resolution Mass Spectrometry. Molecular Chemistry of Organic Aerosols Through the Application of High Resolution Mass...

  3. Modal aerosol dynamics modeling

    SciTech Connect (OSTI)

    Whitby, E.R.; McMurry, P.H.; Shankar, U.; Binkowski, F.S.

    1991-02-01T23:59:59.000Z

    The report presents the governing equations for representing aerosol dynamics, based on several different representations of the aerosol size distribution. Analytical and numerical solution techniques for these governing equations are also reviewed. Described in detail is a computationally efficient numerical technique for simulating aerosol behavior in systems undergoing simultaneous heat transfer, fluid flow, and mass transfer in and between the gas and condensed phases. The technique belongs to a general class of models known as modal aerosol dynamics (MAD) models. These models solve for the temporal and spatial evolution of the particle size distribution function. Computational efficiency is achieved by representing the complete aerosol population as a sum of additive overlapping populations (modes), and solving for the time rate of change of integral moments of each mode. Applications of MAD models for simulating aerosol dynamics in continuous stirred tank aerosol reactors and flow aerosol reactors are provided. For the application to flow aerosol reactors, the discussion is developed in terms of considerations for merging a MAD model with the SIMPLER routine described by Patankar (1980). Considerations for incorporating a MAD model into the U.S. Environmental Protection Agency's Regional Particulate Model are also described. Numerical and analytical techniques for evaluating the size-space integrals of the modal dynamics equations (MDEs) are described. For multimodal logonormal distributions, an analytical expression for the coagulation integrals of the MDEs, applicable for all size regimes, is derived, and is within 20% of accurate numerical evaluation of the same moment coagulation integrals. A computationally efficient integration technique, based on Gauss-Hermite numerical integration, is also derived.

  4. Role of ammonia chemistry and coarse mode aerosols in global climatological inorganic aerosol distributions

    E-Print Network [OSTI]

    Zender, Charles

    1 Role of ammonia chemistry and coarse mode aerosols in global climatological inorganic aerosol distributions Chao Luo1 , Charles S. Zender1 , Huisheng Bian2 , Swen Metzger3 Abstract We use an inorganic aerosol thermodynamic equilibrium model

  5. EMSL - Atmospheric Aerosol Systems

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    scienceatmospheric The Atmospheric Aerosol Systems Science Theme focuses on understanding the chemistry, physics and molecular-scale dynamics of aerosols for model...

  6. Modeling aerosol growth by aqueous chemistry in nonprecipitating stratiform cloud

    SciTech Connect (OSTI)

    Ovchinnikov, Mikhail; Easter, Richard C.

    2010-07-29T23:59:59.000Z

    A new microphysics module based on a two-dimensional (2D) joint size distribution function representing both interstitial and cloud particles is developed and applied to studying aerosol processing in non-precipitating stratocumulus clouds. The module is implemented in a three-dimensional dynamical framework of a large-eddy simulation (LES) model and in a trajectory ensemble model (TEM). Both models are used to study the modification of sulfate aerosol by the activation - aqueous chemistry - resuspension cycle in shallow marine stratocumulus clouds. The effect of particle mixing and different size-distribution representations on modeled aerosol processing are studied in a comparison of the LES and TEM simulations with the identical microphysics treatment exposes and a comparison of TEM simulations with a 2D fixed and moving bin microphysics. Particle mixing which is represented in LES and neglected in the TEM leads to the mean relative per particle dry mass change in the TEM simulations being about 30% lower than in analogous subsample of LES domain. Particles in the final LES spectrum are mixed in from different “parcels”, some of which have experienced longer in-cloud residence times than the TEM parcels, all of which originated in the subcloud layer, have. The mean relative per particle dry mass change differs by 14% between TEM simulations with fixed and moving bin microphysics. Finally, the TEM model with the moving bin microphysics is used to evaluate assumptions about liquid water mass partitioning among activated cloud condensation nuclei (CCN) of different dry sizes. These assumptions are used in large-scale models to map the bulk aqueous chemistry sulfate production, which is largely proportional to the liquid water mass, to the changes in aerosol size distribution. It is shown that the commonly used assumptions that the droplet mass is independent of CCN size or that the droplet mass is proportional to the CCN size to the third power do not perform well in the considered case. The explicitly predicted water partitioning indicates that the mean mass of droplets participating in the models aqueous chemistry calculations is proportional to the dry CCN size.

  7. Role of ammonia chemistry and coarse mode aerosols in global climatological inorganic aerosol distributions

    E-Print Network [OSTI]

    Luo, Chao; Zender, Charles S; Bian, Huisheng; Metzger, Swen

    2007-01-01T23:59:59.000Z

    times of tropospheric aerosols inferred from a global three-sional simulation of 210Pb aerosols. Journal of Geophysicalof sulfate and nitrate aerosol. Atmospheric Environ- ment

  8. CADS:Cantera Aerosol Dynamics Simulator.

    SciTech Connect (OSTI)

    Moffat, Harry K.

    2007-07-01T23:59:59.000Z

    This manual describes a library for aerosol kinetics and transport, called CADS (Cantera Aerosol Dynamics Simulator), which employs a section-based approach for describing the particle size distributions. CADS is based upon Cantera, a set of C++ libraries and applications that handles gas phase species transport and reactions. The method uses a discontinuous Galerkin formulation to represent the particle distributions within each section and to solve for changes to the aerosol particle distributions due to condensation, coagulation, and nucleation processes. CADS conserves particles, elements, and total enthalpy up to numerical round-off error, in all of its formulations. Both 0-D time dependent and 1-D steady state applications (an opposing-flow flame application) have been developed with CADS, with the initial emphasis on developing fundamental mechanisms for soot formation within fires. This report also describes the 0-D application, TDcads, which models a time-dependent perfectly stirred reactor.

  9. Application of computational fluid dynamics to aerosol sampling and concentration

    E-Print Network [OSTI]

    Hu, Shishan

    2009-05-15T23:59:59.000Z

    An understanding of gas-liquid two-phase interactions, aerosol particle deposition, and heat transfer is needed. Computational Fluid Dynamics (CFD) is becoming a powerful tool to predict aerosol behavior for related design work. In this study...

  10. A Computational Approach to Understanding Aerosol Formation and Oxidant Chemistry in the Troposphere

    SciTech Connect (OSTI)

    Francisco, Joseph S.; Kathmann, Shawn M.; Schenter, Gregory K.; Dang, Liem X.; Xantheas, Sotiris S.; Garrett, Bruce C.; Du, Shiyu; Dixon, David A.; Bianco, Roberto; Wang, Shuzhi; Hynes, James T.; Morita, Akihiro; Peterson, Kirk A.

    2006-04-18T23:59:59.000Z

    An understanding of the mechanisms and kinetics of aerosol formation and ozone production in the troposphere is currently a high priority because these phenomena are recognized as two major effects of energy-related air pollution. Atmospheric aerosols are of concern because of their effect on visibility, climate, and human health. Equally important, aerosols can change the chemistry of the atmosphere, in dramatic fashion, by providing new chemical pathways (in the condensed phase) unavailable in the gas phase. The oxidation of volatile organic compounds (VOCs) and inorganic compounds (e.g., sulfuric acid, ammonia, nitric acid, ions, and mineral) can produce precursor molecules that act as nucleation seeds. The U.S. Department of Energy (DOE) Atmospheric Chemistry Program (ACP) has identified the need to evaluate the causes of variations in tropospheric aerosol chemical composition and concentrations, including determining the sources of aerosol particles and the fraction of such that are of primary and secondary origin. In particular, the ACP has called for a deeper understanding into aerosol formation because nucleation creates substantial concentrations of fresh particles that, via growth and coagulation, influence the Earth's radiation budget. Tropospheric ozone is also of concern primarily because of its impact on human health. Ozone levels are controlled by NOx and by VOCs in the lower troposphere. The VOCs can be either from natural emissions from such sources as vegetation and phytoplankton or from anthropogenic sources such as automobiles and oil-fueled power production plants. The major oxidant for VOCs in the atmosphere is the OH radical. With the increase in VOC emissions, there is rising concern regarding the available abundance of HOx species needed to initiate oxidation. Over the last five years, there have been four field studies aimed at initial measurements of HOx species (OH and HO? radicals). These measurements revealed HOx levels that are two to four times higher than expected from the commonly assumed primary sources. Such elevated abundances of HOx imply a more photochemically active troposphere than previously thought. This implies that rates of ozone formation in the lower region of the atmosphere and the oxidation of SO? can be enhanced, thus promoting the formation of new aerosol properties. Central to unraveling this chemistry is the ability to assess the photochemical product distributions resulting from the photodissociation of by-products of VOC oxidation. We propose to use state-of-the-art theoretical techniques to develop a detailed understanding of the mechanisms of aerosol formation in multicomponent (mixed chemical) systems and the photochemistry of atmospheric organic species. The aerosol studies involve an approach that determines homogeneous gas-particle nucleation rates from knowledge of the molecular interactions that are used to define properties of molecular clusters. Over the past several years we developed Dynamical Nucleation Theory (DNT), a novel advance in the theoretical description of homogeneous gas-liquid nucleation, and applied it to gas-liquid nucleation of a single component system (e.g., water). The goal of the present research is to build upon these advances by extending the theory to multicomponent systems important in the atmosphere (such as clusters containing sulfuric acid, water, ions, ammonia, and organics). In addition, high-level ab initio electronic structure calculations will be used to unravel the chemical reactivity of the OH radical and water clusters.

  11. Atmospheric Aerosol Chemistry, Climate Change, and Air Quality

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    aerosols, or OA, containing nitrogen- containing organic compounds (NOC) and only carbon, hydrogen, and oxygen (CHO). They uncovered a new method for investigating OA that may lead...

  12. Multicomponent aerosol dynamic of the Pb-O[sub 2] system in a bench scale flame incinerator

    SciTech Connect (OSTI)

    Lin, W.Y.; Sethi, V.; Biswas, P.

    1992-01-01T23:59:59.000Z

    The article gives results of a study to understand the formation and growth of lead particles in a flame incinerator. A bench scale flame incinerator was used to perform controlled experiments with lead acetate as a test compound. A dilution probe (in conjunction with real-time aerosol instruments) was used to measure the evolution of the particle size distribution at different locations in the flame region. A multicomponent lognormal aerosol model was developed accounting for the chemistry of the lead-oxygen system, and for such aerosol dynamic phenomena as nucleation, coagulation, and condensation. Reasonable agreement was obtained between the predictions of the model using appropriate kinetic parameters and the experimental results.

  13. Soot particle aerosol dynamics at high pressure

    SciTech Connect (OSTI)

    Harris, S.J. (General Motors Research Labs., Warren, MI (USA). Physics Dept.); Kennedy, I.M. (California Univ., Davis, CA (USA). Dept. of Mechanical Engineering)

    1989-12-01T23:59:59.000Z

    The authors have used detailed calculations to analyze the coagulation dynamics of a soot aerosol at high pressures (20 and 50 atm). They find that the soot size distribution is altered compared to lower-pressure conditions because the mean free path at high pressures is reduced to the point that the particles are similar in size to the mean free path. At lower pressures the form of the size distribution becomes constant (self-preserving) in time, allowing optical measurements to be easily interpreted. However, the authors find that at pressures above about 5 atm the shape of the size distribution continually changes. As a result, proper and accurate interpretation of optical data at high pressures is more difficult than at lower pressures.

  14. Study of Heterogeneouse Processes Related to the Chemistry of Tropospheric Oxidants and Aerosols

    SciTech Connect (OSTI)

    Davidovits, Paul; Worsnop, D R; Jayne, J T; Colb, C E

    2013-02-13T23:59:59.000Z

    The objective of the studies was to elucidate the heterogeneous chemistry of tropospheric aerosols. Experiments were designed to measure both specifically needed parameters, and to obtain systematic data required to build a fundamental understanding of the nature of gas-surface physical and chemical interactions

  15. Computational Fluid Dynamics Study of Aerosol Transport and Deposition Mechanisms

    E-Print Network [OSTI]

    Tang, Yingjie

    2012-07-16T23:59:59.000Z

    In this work, various aerosol particle transport and deposition mechanisms were studied through the computational fluid dynamics (CFD) modeling, including inertial impaction, gravitational effect, lift force, interception, and turbophoresis, within...

  16. AT772, Fall 2007 Aerosol Chemistry and Physics

    E-Print Network [OSTI]

    Relevant program August 22 W 1 Introduction Aerosol size distributions Properties of lognormal distributions Fitting model size distribution functions to data [Other functions (e.g., gamma, power law)] 8 distribution 29 W Extra 1/2 31 3b 4 Overview, continued Time scales for diffusion, coagulation, condensational

  17. Use of a continuous stirred tank reactor for the study of aqueous aerosol chemistry

    SciTech Connect (OSTI)

    Adkins, C.L.J.

    1988-01-01T23:59:59.000Z

    Atmospheric aerosol chemistry is important in areas ranging from urban air pollution to cloud formation. It has long been supposed that droplet-phase reactions account for a significant fraction of the atmospheric conversion of SO/sub 2/ to sulfate. In this thesis a reactor system is developed to carry out gas-aerosol reactions under humid, ambient-like conditions. The apparatus consists of a continuous stirred tank reactor (CSTR) in which the growth of the aqueous aerosol is measured. Absence of mass transfer limitation, coagulation, and nucleation ensure that particle growth is direct evidence of reaction. Special care is taken to minimize size biasing of the aqueous aerosol in the electrostatics classifier used to measure the reactor feed and effluent distributions. Aerosol behavior in the reactor is modeled assuming an ideal CSTR and, given the solution thermodynamics and equilibrium chemistry, the effluent distribution can be predicted using one of the proposed reaction rate mechanisms. Experiments were performed using a pure MnSO/sub 4/ or a MnSO/sub 4/minus// Na/sub 2/SO/sub 4/ mixture feed aerosol. The relative humidity ranged from 86 to 94% and 0.1 ppm < p/sub SO/sub 2// < 50 ppm. The various rate expressions proposed for this system in the literature resulted in varying estimates of growth. When reactor conditions were similar to those at which the rate expression was determined, the agreement between the predicted and observed distributions improved. This indicates that use of a rate expressions beyond its specified range may result in erroneous predictions.

  18. Atmospheric Aerosols Workshop | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Atmospheric Aerosols Workshop Atmospheric Aerosols Workshop EMSL Science Theme Advisory Panel Workshop - Atmospheric Aerosol Chemistry, Climate Change, and Air Quality. Baer DR, BJ...

  19. The modeling of aerosol dynamics during degraded core events

    SciTech Connect (OSTI)

    Clausse, A.; Lahey, R.T. Jr.

    1989-01-01T23:59:59.000Z

    There is substantial interest in developing simple, yet accurate, models for the prediction of aerosol dynamics during degraded core events. The exact aerosol transport equation is given by {partial derivative}n(v,t)/{partial derivative}t = 1/2 {integral}{sub 0}{sup {infinity}} K(u,v {minus} u)n(u,t)n(v {minus} u,t)du {minus} {integral}{sub 0}{sup {infinity}} K(u,v)n(v,t)n(u,t)du {minus} n(v,t)c(v)/h + n{sub p}(v), where n(v,t) is the particle size density distribution function. The kernel, K(v,u), is related to the frequency of coagulation between aerosol particles of volume u and v, and the quantity c(v) is the deposition velocity. The quantity h is the effective height for deposition of aerosol; it is the volume of the aerosol cloud divided by the projected horizontal area A. Finally, the term n{sub p} (v) is the source rate of aerosol. Evaluation of the above equation is discussed.

  20. aerosol dynamics simulator: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    aerosol dynamics simulator First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 5, 79658026, 2005 Simulating...

  1. Toxicity of atmospheric aerosols on marine phytoplankton

    E-Print Network [OSTI]

    2009-01-01T23:59:59.000Z

    metals added from these aerosols to the bioassay incubationsreleased to seawater from the aerosol filters after Author4605 CHEMISTRY Atmospheric aerosol deposition CHEMISTRY

  2. Description and Evaluation of Tropospheric Chemistry and Aerosols in the Community Earth System Model (CESM1.2)

    SciTech Connect (OSTI)

    Tilmes, S.; Lamarque, J.-F.; Emmons, L.; Kinnison, Douglas E.; Ma, Po-Lun; Liu, Xiaohong; Ghan, Steven J.; Bardeen, C.; Arnold, S.; Deeter, M.; Vitt, Francis; Ryerson, T. B.; Elkins, J. W.; Moore, F.; Spackman, R.; Martin, M. V.

    2015-01-01T23:59:59.000Z

    The Community Atmosphere Model (CAM), version 5, is now coupled to extensive tropospheric and stratospheric chemistry, called CAM5-chem, and is available in addition to CAM4-chem in the Community Earth System Model (CESM) version 1.2. Both configurations are well suited as tools for atmospheric-chemistry modeling studies in the troposphere and lower stratosphere, whether with internally derived “free running” (FR) meteorology, or “specified dynamics” (SD). The main focus of this paper is to compare the performance of these configurations against observations from surface, aircraft, and satellite, as well as understand the origin of the identified differences. We particularly focus on comparing present-day methane lifetime estimates within the different model configurations, which range between 7.8 years in the SD configuration of CAM5-chem and 8.8 years in the FR configuration of CAM4-chem. We find that tropospheric surface area density is an important factor in controlling the burden of the hydroxyl radical (OH), which causes differences in tropical methane lifetime of about half a year between CAM4-chem and CAM5-chem. In addition, different distributions of nitrogen oxides (NOx) produced from lightning production explain about half of the difference between SD and FR model versions in both CAM4-chem and CAM5-chem. Remaining differences in the tropical OH burden are due to enhanced tropical ozone burden in SD configurations compared to the FR versions, which are not only caused by differences in chemical production or loss, but also by transport and mixing. For future studies, we recommend the use of CAM5-chem, due to improved aerosol description and inclusion of aerosol-cloud interactions. However, smaller tropospheric surface area density in the current version of CAM5-chem compared to CAM4-chem results in larger oxidizing capacity in the troposphere and therefore a shorter methane lifetime.

  3. he Impact of Primary Marine Aerosol on Atmospheric Chemistry, Radiation and Climate: A CCSM Model Development Study

    SciTech Connect (OSTI)

    Keene, William C. [University of Virginia] [University of Virginia; Long, Michael S. [University of Virginia] [University of Virginia

    2013-05-20T23:59:59.000Z

    This project examined the potential large-scale influence of marine aerosol cycling on atmospheric chemistry, physics and radiative transfer. Measurements indicate that the size-dependent generation of marine aerosols by wind waves at the ocean surface and the subsequent production and cycling of halogen-radicals are important but poorly constrained processes that influence climate regionally and globally. A reliable capacity to examine the role of marine aerosol in the global-scale atmospheric system requires that the important size-resolved chemical processes be treated explicitly. But the treatment of multiphase chemistry across the breadth of chemical scenarios encountered throughout the atmosphere is sensitive to the initial conditions and the precision of the solution method. This study examined this sensitivity, constrained it using high-resolution laboratory and field measurements, and deployed it in a coupled chemical-microphysical 3-D atmosphere model. First, laboratory measurements of fresh, unreacted marine aerosol were used to formulate a sea-state based marine aerosol source parameterization that captured the initial organic, inorganic, and physical conditions of the aerosol population. Second, a multiphase chemical mechanism, solved using the Max Planck Institute for Chemistryâ??s MECCA (Module Efficiently Calculating the Chemistry of the Atmosphere) system, was benchmarked across a broad set of observed chemical and physical conditions in the marine atmosphere. Using these results, the mechanism was systematically reduced to maximize computational speed. Finally, the mechanism was coupled to the 3-mode modal aerosol version of the NCAR Community Atmosphere Model (CAM v3.6.33). Decadal-scale simulations with CAM v.3.6.33, were run both with and without reactive-halogen chemistry and with and without explicit treatment of particulate organic carbon in the marine aerosol source function. Simulated results were interpreted (1) to evaluate influences of marine aerosol production on the microphysical properties of aerosol populations and clouds over the ocean and the corresponding direct and indirect effects on radiative transfer; (2) atmospheric burdens of reactive halogen species and their impacts on O3, NOx, OH, DMS, and particulate non-sea-salt SO42-; and (3) the global production and influences of marine-derived particulate organic carbon. The model reproduced major characteristics of the marine aerosol system and demonstrated the potential sensitivity of global, decadal-scale climate metrics to multiphase marine-derived components of Earthâ??s troposphere. Due to the combined computational burden of the coupled system, the currently available computational resources were the limiting factor preventing the adequate statistical analysis of the overall impact that multiphase chemistry might have on climate-scale radiative transfer and climate.

  4. Modeling Space-Time Dynamics of Aerosols Using Satellite Data and Atmospheric Transport Model Output

    E-Print Network [OSTI]

    Shi, Tao

    Modeling Space-Time Dynamics of Aerosols Using Satellite Data and Atmospheric Transport Model of aerosol optical depth across mainland Southeast Asia. We include a cross validation study to assess

  5. Numerical solutions of the aerosol general dynamic equation for nuclear reactor safety studies

    SciTech Connect (OSTI)

    Park, J.W.

    1988-01-01T23:59:59.000Z

    Methods and approximations inherent in modeling of aerosol dynamics and evolution for nuclear reactor source term estimation have been investigated. Several aerosol evolution problems are considered to assess numerical methods of solving the aerosol dynamic equation. A new condensational growth model is constructed by generalizing Mason's formula to arbitrary particle sizes, and arbitrary accommodation of the condensing vapor and background gas at particle surface. Analytical solution is developed for the aerosol growth equation employing the new condensation model. The space-dependent aerosol dynamic equation is solved to assess implications of spatial homogenization of aerosol distributions. The results of our findings are as follows. The sectional method solving the aerosol dynamic equation is quite efficient in modeling of coagulation problems, but should be improved for simulation of strong condensation problems. The J-space transform method is accurate in modeling of condensation problems, but is very slow. For the situation considered, the new condensation model predicts slower aerosol growth than the corresponding isothermal model as well as Mason's model, the effect of partial accommodation is considerable on the particle evolution, and the effect of the energy accommodation coefficient is more pronounced than that of the mass accommodation coefficient. For the initial conditions considered, the space-dependent aerosol dynamics leads to results that are substantially different from those based on the spatially homogeneous aerosol dynamic equation.

  6. Atmospheric Aerosol Systems | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science Themes Atmospheric Aerosol Systems Overview Atmospheric Aerosol Systems Biosystem Dynamics & Design Energy Materials & Processes Terrestrial & Subsurface Ecosystems...

  7. Gaseous Chemistry and Aerosol Mechanism Developments for Version 3.5.1 of the Online Regional Model, WRF-Chem

    SciTech Connect (OSTI)

    Archer-Nicholls, Scott; Lowe, Douglas; Utembe, Steve; Allan, James D.; Zaveri, Rahul A.; Fast, Jerome D.; Hodnebrog, Oivind; Denier van der Gon, Hugo; McFiggans, Gordon

    2014-11-08T23:59:59.000Z

    We have made a number of developments in the regional coupled model WRF-Chem, with the aim of making the model more suitable for prediction of atmospheric composition and of interactions between air quality and weather. We have worked on the European domain, with a particular focus on making the model suitable for the study of night time chemistry and oxidation by the nitrate radical in the UK atmosphere. A reduced form of the Common Reactive Intermediates gas-phase chemical mechanism (CRIv2-R5) has been implemented to enable more explicit simulation of VOC degradation. N2O5 heterogeneous chemistry has been added to the existing sectional MOSAIC aerosol module, and coupled to both the CRIv2-R5 and existing CBM-Z gas phase scheme. Modifications have also been made to the sea-spray aerosol emission representation, allowing the inclusion of primary organic material in sea-spray aerosol. Driven by appropriate emissions, wind fields and chemical boundary conditions, implementation of the different developments is illustrated in order to demonstrate the impact that these changes have in the North-West European domain. These developments are now part of the freely available WRF-Chem distribution.

  8. Direct measurements of marine aerosols to examine the influence of biological activity, anthropogenic emissions, and secondary processing on particle chemistry

    E-Print Network [OSTI]

    Gaston, Cassandra Jayne

    2012-01-01T23:59:59.000Z

    for fog processing of individual aerosol particles, Atmos.of marine secondary organic aerosol from biogenic amines,Pacific and their impacts on aerosol hygroscopicity in the

  9. Air Pollution Physics and Chemistry EAS/CEE 6790 Fall 2010 Aerosols

    E-Print Network [OSTI]

    Weber, Rodney

    -3 ). 4 (a). For each bin in the size distribution of part 1, assuming monodisperse coagulation, is coagulation important for this aerosol distribution given the typical lifetime of tropospheric aerosols? #12; by 1/2, then determine the average for the whole size distribution. Note, that this is a size

  10. Protein-directed dynamic combinatorial chemistry 

    E-Print Network [OSTI]

    Bhat, Venugopal T.

    2011-11-23T23:59:59.000Z

    -friendly conditions. In the presence of aniline as a trans-imination catalyst, acylhydrazone dynamic combinatorial libraries equilibrate rapidly at pH 6.2 and are switched off by an increase in pH. We designed acylhydrazone libraries targeting the enzyme superfamily...

  11. Phenol-benzene complexation dynamics: Quantum chemistry calculation, molecular dynamics simulations, and two dimensional IR spectroscopy

    E-Print Network [OSTI]

    Fayer, Michael D.

    Phenol-benzene complexation dynamics: Quantum chemistry calculation, molecular dynamics simulations the nature and dynamics of the phenol-benzene complex in the mixed solvent, benzene/CCl4. Under thermal used for the phenol-benzene interaction in the MD simulations is in good accord with the highest level

  12. Chemistry of carbonaceous aerosols : studies of atmospheric processing and OH-initiated oxidation

    E-Print Network [OSTI]

    Johnson, Kirsten S. (Kirsten Sue)

    2008-01-01T23:59:59.000Z

    Carbonaceous aerosols are among the most prevalent yet least understood constituents of the atmosphere, particularly in urban environments. We have performed analyses of field samples and laboratory studies to probe the ...

  13. A one-dimensional sectional model to simulate multicomponent aerosol dynamics in the marine boundary layer 1. Model description

    SciTech Connect (OSTI)

    Fitzgerald, J.W.; Hoppel, W.A. [Remote Sensing Division, Naval Research Laboratory, Washington, District of Columbia (United States)] [Remote Sensing Division, Naval Research Laboratory, Washington, District of Columbia (United States); Gelbard, F. [Modeling and Analysis Department, Sandia National Laboratories, Albuquerque, New Mexico (United States)] [Modeling and Analysis Department, Sandia National Laboratories, Albuquerque, New Mexico (United States)

    1998-07-01T23:59:59.000Z

    A one-dimensional, multicomponent sectional model has been developed to simulate the temporal and vertical variations of the aerosol size distribution and composition in the marine boundary layer (MBL). An important aspect of the model is its ability to handle the transport of aerosols in an atmosphere with humidity gradients with no numerical diffusion caused by the swelling and shrinking of the particles as they move through the humidity gradients. This is achieved by rewriting the aerosol general dynamical equation (GDE) in terms of dry radius thus transferring all variations in radius caused by temporal and spatial humidity variations to the rate coefficients appearing in the equations. The model then solves the new GDE in fixed dry size sections, with the humidity dependence of the processes now included in variable coefficients. This procedure also results in correct gradient transport. A limiting assumption is that the particles equilibrate instantaneously with the ambient water vapor. This assumption limits the maximum particle size which can be treated in the model to ambient (wet) radii less than about 30 {mu}m. All processes currently believed to be important in shaping the MBL size distribution are included in the current version of the model. These include generation of sea-salt aerosol at the ocean surface, nucleation of new particles, coagulation, growth due to condensation of gas-phase reaction products, growth due to sulfate formation during cloud processing, precipitation scavenging, surface deposition, turbulent mixing, gravitational settling, and exchange with the free troposphere. Simple gas-phase chemistry which includes the oxidation of dimethylsulfide and SO{sub 2} to sulfate is incorporated in the current version of the model. {copyright} 1998 American Geophysical Union

  14. Simulation of aerosol dynamics: a comparative review of mathematical models

    SciTech Connect (OSTI)

    Seigneur, C.; Hudischewskyj, A.B.; Seinfeld, J.H.; Whitby, K.T.; Whitby, E.R.

    1986-01-01T23:59:59.000Z

    Three modeling approaches used are based-continuous, discrete (sectional), and parameterized representations of the aerosol size distribution. Simulations of coagulation and condensation are performed with the three models for clear, hazy, and urban atmospheric conditions. Relative accuracies and computational costs are compared. Reference for the comparison is the continuous approach. The results of the study provide useful information for the selection of an aerosol model, depending on the accuracy requirements and computational constraints associated with a specific application.

  15. Carbon oxidation state as a metric for describing the chemistry of atmospheric organic aerosol

    SciTech Connect (OSTI)

    Massachusetts Institute of Technology; Kroll, Jesse H.; Donahue, Neil M.; Jimenez, Jose L.; Kessler, Sean H.; Canagaratna, Manjula R.; Wilson, Kevin R.; Altieri, Katye E.; Mazzoleni, Lynn R.; Wozniak, Andrew S.; Bluhm, Hendrik; Mysak, Erin R.; Smith, Jared D.; Kolb, Charles E.; Worsnop, Douglas R.

    2010-11-05T23:59:59.000Z

    A detailed understanding of the sources, transformations, and fates of organic species in the environment is crucial because of the central roles that organics play in human health, biogeochemical cycles, and Earth's climate. However, such an understanding is hindered by the immense chemical complexity of environmental mixtures of organics; for example, atmospheric organic aerosol consists of at least thousands of individual compounds, all of which likely evolve chemically over their atmospheric lifetimes. Here we demonstrate the utility of describing organic aerosol (and other complex organic mixtures) in terms of average carbon oxidation state (OSC), a quantity that always increases with oxidation, and is readily measured using state-of-the-art analytical techniques. Field and laboratory measurements of OSC , using several such techniques, constrain the chemical properties of the organics and demonstrate that the formation and evolution of organic aerosol involves simultaneous changes to both carbon oxidation state and carbon number (nC).

  16. Aerosol composition, chemistry, and source characterization during the 2008 VOCALS Experiment

    SciTech Connect (OSTI)

    Lee, Y.; Springston, S.; Jayne, J.; Wang, J.; Senum, G.; Hubbe, J.; Alexander, L.; Brioude, J.; Spak, S.; Mena-Carrasco, M.; Kleinman, L.; Daum, P.

    2010-03-15T23:59:59.000Z

    Chemical composition of fine aerosol particles over the northern Chilean coastal waters was determined onboard the U.S. DOE G-1 aircraft during the VOCALS (VAMOS Ocean-Cloud-Atmosphere-Land Study) field campaign between October 16 and November 15, 2008. SO42-, NO3-, NH4+, and total organics (Org) were determined using an Aerodyne Aerosol Mass Spectrometer, and SO42-, NO3-, NH4+, Na+, Cl-, CH3SO3-, Mg2+, Ca2+, and K+ were determined using a particle-into-liquid sampler-ion chromatography technique. The results show the marine boundary layer (MBL) aerosol mass was dominated by non- sea-salt SO42- followed by Na+, Cl-, Org, NO3-, and NH4+, in decreasing importance; CH3SO3-, Ca2+, and K+ rarely exceeded their respective limits of detection. The SO42- aerosols were strongly acidic as the equivalent NH4+ to SO42- ratio was only {approx}0.25 on average. NaCl particles, presumably of sea-salt origin, showed chloride deficits but retained Cl- typically more than half the equivalency of Na+, and are externally mixed with the acidic sulfate aerosols. Nitrate was observed only on sea-salt particles, consistent with adsorption of HNO3 on sea-salt aerosols, responsible for the Cl- deficit. Dust particles appeared to play a minor role, judging from the small volume differences between that derived from the observed mass concentrations and that calculated based on particle size distributions. Because SO42- concentrations were substantial ({approx}0.5 - {approx}3 {micro}g/m3) with a strong gradient (highest near the shore), and the ocean-emitted dimethylsulfide and its unique oxidation product, CH3SO3-, were very low (i.e., {le} 40 parts per trillion and <0.05 {micro}g/m3, respectively), the observed SO42- aerosols are believed to be primarily of terrestrial origin. Back trajectory calculations indicate sulfur emissions from smelters and power plants along coastal regions of Peru and Chile are the main sources of these SO4- aerosols. However, compared to observations, model calculations appeared to underestimate sulfate concentrations based on an existing emission inventory. The agreement between observations and model predictions of CO as well as total sulfur is reexamined in this work with a new emission inventory made available recently.

  17. Air Pollution Physics and Chemistry EAS 6790 Home Work Assignment No. 5, Aerosols: CMB Modeling

    E-Print Network [OSTI]

    Weber, Rodney

    or Species Tailpipe Fuel Oil Flyash Soildust Seasalt Ambient Aerosol Al 0.0 0.008 0.082 0.000055 0.008 Ba 0 of these primary sources are underlined. Is it a good assumption that ambient loadings of the tracer species derive solely from the associated primary source? Under this assumption, estimate the contributions (in percent

  18. Modeling particle formation during low-pressure silane oxidation: Detailed chemical kinetics and aerosol dynamics

    E-Print Network [OSTI]

    Zachariah, Michael R.

    that the generation of SiOHx species from fast gas- phase reactions can significantly degrade film quality. Based conservation equations and a moment-type aerosol dynamics model were formulated for a batch reactor undergoing to impurity diffusion.1 During LPCVD film deposition rates are limited by the gas-phase nucleation

  19. Laboratory Studies of the Reactive Chemistry and Changing CCN Properties of Secondary Organic Aerosol, Including Model Development

    SciTech Connect (OSTI)

    Scot Martin

    2013-01-31T23:59:59.000Z

    The chemical evolution of secondary-organic-aerosol (SOA) particles and how this evolution alters their cloud-nucleating properties were studied. Simplified forms of full Koehler theory were targeted, specifically forms that contain only those aspects essential to describing the laboratory observations, because of the requirement to minimize computational burden for use in integrated climate and chemistry models. The associated data analysis and interpretation have therefore focused on model development in the framework of modified kappa-Koehler theory. Kappa is a single parameter describing effective hygroscopicity, grouping together several separate physicochemical parameters (e.g., molar volume, surface tension, and van't Hoff factor) that otherwise must be tracked and evaluated in an iterative full-Koehler equation in a large-scale model. A major finding of the project was that secondary organic materials produced by the oxidation of a range of biogenic volatile organic compounds for diverse conditions have kappa values bracketed in the range of 0.10 +/- 0.05. In these same experiments, somewhat incongruently there was significant chemical variation in the secondary organic material, especially oxidation state, as was indicated by changes in the particle mass spectra. Taken together, these findings then support the use of kappa as a simplified yet accurate general parameter to represent the CCN activation of secondary organic material in large-scale atmospheric and climate models, thereby greatly reducing the computational burden while simultaneously including the most recent mechanistic findings of laboratory studies.

  20. Simulation of aerosol dynamics: A comparative review of algorithms used in air quality models

    SciTech Connect (OSTI)

    Zhang, Y.; Seigneur, C.; Seinfeld, J.H.; Jacobson, M.Z.; Binkowski, F.S.

    1999-01-01T23:59:59.000Z

    A comparative review of algorithms currently used in air quality models to simulate aerosol dynamics is presented. This review addresses coagulation, condensational growth, nucleation, and gas/particle mass transfer. Two major approaches are used in air quality models to represent the particle size distribution: (1) the sectional approach in which the size distribution is discretized into sections and particle properties are assumed to be constant over particle size sections and (2) the modal approach in which the size distribution is approximated by several modes and particle properties are assumed to be uniform in each mode. The results of this study provide useful information to select algorithms to simulate aerosol dynamics in air quality models and to improve the accuracy of existing algorithms.

  1. Real time in situ detection of organic nitrates in atmospheric aerosols

    E-Print Network [OSTI]

    Rollins, Andrew W.

    2011-01-01T23:59:59.000Z

    Biogenic Secondary Organic Aerosol. J. Phys. Chem. A 2008,H. Secondary organic aerosol (SOA) formation from reactionsec- ondary organic aerosol yields. Atmospheric Chemistry

  2. Direct measurements of marine aerosols to examine the influence of biological activity, anthropogenic emissions, and secondary processing on particle chemistry

    E-Print Network [OSTI]

    Gaston, Cassandra Jayne

    2012-01-01T23:59:59.000Z

    radiation contributing to the aerosol direct effect [IPCC, 2007; Poschl, 2005] and also serve as nuclei for the formation of cloud

  3. The coupling of dynamics and molecular chemistry in galaxies

    E-Print Network [OSTI]

    F. Combes

    2007-09-24T23:59:59.000Z

    While the best tracer of the molecular component and its dynamics in galaxies is the CO molecule, which excitation is revealed by its isotopic and (2-1)/(1-0) ratios, the denser gas is revealed by molecules such as HCN, HNC, HCO+ or CN, which are now widely used to probe star formation regions, or to quantify the impact of the nuclear activity on the interstellar medium. This paper reviews recent observations in nearby galaxies, where these molecular line ratios serve as diagnostic tools of the physical conditions of the gas and also of its chemical properties. Those differ significantly according to the proximity of an AGN or of a starburst. The origin of the differences is not yet well known and could be due to different densities, temperatures, chemical abundances or non-collisional excitation of the gas (e.g. Aalto et al 2007, Krips et al 2007). HCN or HNC line enhancements can be caused not only by higher gas densities/temperatures, but also UV/X-ray radiation, and global IR pumping. The chemistry can be dominated by PDR regions near a starburst, or X-ray dominated in a molecular torus surrounding an AGN (XDR regions). The molecular line ratios expected in those regions vary according to the different models (Meijerink et al. 2007).

  4. Discovery of An Aurora Kinase Inhibitor Through Site-Specific Dynamic Combinatorial Chemistry

    SciTech Connect (OSTI)

    Cancilla, M.T.; He, M.M.; Viswanathan, N.; Simmons, R.L.; Taylor, M.; Fung, A.D.; Cao, K.; Erlanson, D.A.

    2009-05-12T23:59:59.000Z

    We demonstrate a fragment-based lead discovery method that combines site-directed ligand discovery with dynamic combinatorial chemistry. Our technique targets dynamic combinatorial screening to a specified region of a protein by using reversible disulfide chemistry. We have used this technology to rapidly identify inhibitors of the drug target Aurora A that span the purine-binding site and the adaptive pocket of the kinase. The binding mode of a noncovalent inhibitor has been further characterized through crystallography.

  5. Secondary Ion Mass Spectrometry of Environmental Aerosols

    SciTech Connect (OSTI)

    Gaspar, Daniel J.; Cliff, John B.

    2010-08-01T23:59:59.000Z

    Atmospheric particles influence many aspects of climate, air quality and human health. Understanding the composition, chemistry and behavior of atmospheric aerosols is a key remaining challenge in improving climate models. Furthermore, particles may be traced back to a particular source based on composition, stable isotope ratios, or the presence of particular surface chemistries. Finally, the characterization of atmospheric particles in the workplace plays an important role in understanding the potential for exposure and environmental and human health effects to engineered and natural nanoscale particles. Secondary ion mass spectrometry (SIMS) is a useful tool in determining any of several aspects of the structure, composition and chemistry of these particles. Often used in conjunction with other surface analysis and electron microscopy methods, SIMS has been used to determine or confirm reactions on and in particles, the presence of particular organic species on the surface of atmospheric aerosols and several other interesting and relevant findings. Various versions of SIMS instruments – dynamic SIMS, time of flight secondary ion mass spectrometry or TOF-SIMS, nanoSIMS – have been used to determine specific aspects of aerosol structure and chemistry. This article describes the strengths of each type of SIMS instrument in the characterization of aerosols, along with guidance on sample preparation, specific characterization specific to the particular information sought in the analysis. Examples and guidance are given for each type of SIMS analysis.

  6. Chemistry

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced. C o w l i t z CPlasma of theChemistry

  7. Chemistry

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem NotEnergy,ARMForms AboutRESEARCH CAPABILITIES Thematerials | CenterChemistry

  8. 5, 79658026, 2005 Simulating aerosol

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    composition, number concentration, and size distribution of the global submicrometer aerosol. The present, coagulation, condensation, nucleation of sulfuric acid vapor, aerosol chemistry, cloud processing, and sizeACPD 5, 7965­8026, 2005 Simulating aerosol microphysics with ECHAM/MADE A. Lauer et al. Title Page

  9. VARIATION OF AEROSOL OPTICAL PROPERTIES

    E-Print Network [OSTI]

    Schwartz, Stephen E.

    radiative forcing due to the aerosol, W m-2 FT is the solar constant, W m-2 Ac is the fractional cloud cover;APPROACH TO MODELING AEROSOL RADIATIVE EFFECTS Transport Chemistry Microphysics Removal ModelEmissions Size-distributed Composition Optical Properties Radiative Effects Optics Model Radiation Transfer Model #12;CLASSES OF AEROSOL

  10. Mass spectrometric approaches for chemical characterisation of atmospheric aerosols: critical

    E-Print Network [OSTI]

    Nizkorodov, Sergey

    Mass spectrometric approaches for chemical characterisation of atmospheric aerosols: critical. Atmospheric aerosols have profound effects on the environment through several physicochemical processes on the respiratory and cardiovascular systems. Understanding aerosol atmospheric chemistry and its environmental

  11. Computational fluid dynamics (CFD) simulations of aerosol in a u-shaped steam generator tube 

    E-Print Network [OSTI]

    Longmire, Pamela

    2009-05-15T23:59:59.000Z

    To quantify primary side aerosol retention, an Eulerian/Lagrangian approach was used to investigate aerosol transport in a compressible, turbulent, adiabatic, internal, wall-bounded flow. The ARTIST experimental project ...

  12. Green Chemistry Dynamic Article Links Cite this: Green Chem., 2011, 13, 91

    E-Print Network [OSTI]

    California at Riverside, University of

    Green Chemistry Dynamic Article Links Cite this: Green Chem., 2011, 13, 91 www.rsc.org/greenchem PAPER Renewable gasoline from aqueous phase hydrodeoxygenation of aqueous sugar solutions prepared In this paper we demonstrate an integrated process for the production of high octane gasoline from maple wood

  13. Using Chemistry and Microfluidics To Understand the Spatial Dynamics of Complex Biological Networks

    E-Print Network [OSTI]

    Ismagilov, Rustem F.

    Using Chemistry and Microfluidics To Understand the Spatial Dynamics of Complex Biological Networks of a network are simultaneously considered. Here, we describe chemical concepts and microfluidic tools or computational models can be created by replacing each module with a single reaction. Microfluidics can be used

  14. REPRESENTING AEROSOL DYNAMICS AND PROPERTIES IN CHEMICAL TRANSPORT MODELS BY THE METHOD OF MOMENTS.

    SciTech Connect (OSTI)

    SCHWARTZ,S.E.; MCGRAW,R.; BENKOVITZ,C.M.; WRIGHT,D.L.

    2001-04-01T23:59:59.000Z

    Atmospheric aerosols, suspensions of solid or liquid particles, are an important multi-phase system. Aerosols scatter and absorb shortwave (solar) radiation, affecting climate (Charlson et al., 1992; Schwartz, 1996) and visibility; nucleate cloud droplet formation, modifying the reflectivity of clouds (Twomey et al., 1984; Schwartz and Slingo, 1996) as well as contributing to composition of cloudwater and to wet deposition (Seinfeld and Pandis, 1998); and affect human health through inhalation (NRC, 1998). Existing and prospective air quality regulations impose standards on concentrations of atmospheric aerosols to protect human health and welfare (EPA, 1998). Chemical transport and transformation models representing the loading and geographical distribution of aerosols and precursor gases are needed to permit development of effective and efficient strategies for meeting air quality standards, and for examining aerosol effects on climate retrospectively and prospectively for different emissions scenarios. Important aerosol properties and processes depend on their size distribution: light scattering, cloud nucleating properties, dry deposition, and penetration into airways of lungs. The evolution of the mass loading itself depends on particle size because of the size dependence of growth and removal processes. For these reasons it is increasingly recognized that chemical transport and transformation models must represent not just the mass loading of atmospheric particulate matter but also the aerosol microphysical properties and the evolution of these properties if aerosols are to be accurately represented in these models. If the size distribution of the aerosol is known, a given property can be evaluated as the integral of the appropriate kernel function over the size distribution. This has motivated the approach of determining aerosol size distribution, and of explicitly representing this distribution and its evolution in chemical transport models.

  15. GASFLOW: A Computational Fluid Dynamics Code for Gases, Aerosols, and Combustion, Volume 2: User's Manual

    SciTech Connect (OSTI)

    B. D. Nichols; C. Müller; G. A. Necker; J. R. Travis; J. W. Spore; K. L. Lam; P. Royl; T. L. Wilson

    1998-10-01T23:59:59.000Z

    Los Alamos National Laboratory (LANL) and Forschungszentrum Karlsruhe (FzK) are developing GASFLOW, a three-dimensional (3D) fluid dynamics field code as a best-estimate tool to characterize local phenomena within a flow field. Examples of 3D phenomena include circulation patterns; flow stratification; hydrogen distribution mixing and stratification; combustion and flame propagation; effects of noncondensable gas distribution on local condensation and evaporation; and aerosol entrainment, transport, and deposition. An analysis with GASFLOW will result in a prediction of the gas composition and discrete particle distribution in space and time throughout the facility and the resulting pressure and temperature loadings on the walls and internal structures with or without combustion. A major application of GASFLOW is for predicting the transport, mixing, and combustion of hydrogen and other gases in nuclear reactor containment and other facilities. It has been applied to situations involving transporting and distributing combustible gas mixtures. It has been used to study gas dynamic behavior in low-speed, buoyancy-driven flows, as well as sonic flows or diffusion dominated flows; and during chemically reacting flows, including deflagrations. The effects of controlling such mixtures by safety systems can be analyzed. The code version described in this manual is designated GASFLOW 2.1, which combines previous versions of the United States Nuclear Regulatory Commission code HMS (for Hydrogen Mixing Studies) and the Department of Energy and FzK versions of GASFLOW. The code was written in standard Fortran 90. This manual comprises three volumes. Volume I describes the governing physical equations and computational model. Volume II describes how to use the code to set up a model geometry, specify gas species and material properties, define initial and boundary conditions, and specify different outputs, especially graphical displays. Sample problems are included. Volume III contains some of the assessments performed by LANL and FzK.

  16. GASFLOW: A Computational Fluid Dynamics Code for Gases, Aerosols, and Combustion, Volume 3: Assessment Manual

    SciTech Connect (OSTI)

    C. Müller; E. D. Hughes; G. F. Niederauer; H. Wilkening; J. R. Travis; J. W. Spore; P. Royl; W. Baumann

    1998-10-01T23:59:59.000Z

    Los Alamos National Laboratory (LANL) and Forschungszentrum Karlsruhe (FzK) are developing GASFLOW, a three-dimensional (3D) fluid dynamics field code as a best- estimate tool to characterize local phenomena within a flow field. Examples of 3D phenomena include circulation patterns; flow stratification; hydrogen distribution mixing and stratification; combustion and flame propagation; effects of noncondensable gas distribution on local condensation and evaporation; and aerosol entrainment, transport, and deposition. An analysis with GASFLOW will result in a prediction of the gas composition and discrete particle distribution in space and time throughout the facility and the resulting pressure and temperature loadings on the walls and internal structures with or without combustion. A major application of GASFLOW is for predicting the transport, mixing, and combustion of hydrogen and other gases in nuclear reactor containment and other facilities. It has been applied to situations involving transporting and distributing combustible gas mixtures. It has been used to study gas dynamic behavior in low-speed, buoyancy-driven flows, as well as sonic flows or diffusion dominated flows; and during chemically reacting flows, including deflagrations. The effects of controlling such mixtures by safety systems can be analyzed. The code version described in this manual is designated GASFLOW 2.1, which combines previous versions of the United States Nuclear Regulatory Commission code HMS (for Hydrogen Mixing Studies) and the Department of Energy and FzK versions of GASFLOW. The code was written in standard Fortran 90. This manual comprises three volumes. Volume I describes the governing physical equations and computational model. Volume II describes how to use the code to set up a model geometry, specify gas species and material properties, define initial and boundary conditions, and specify different outputs, especially graphical displays. Sample problems are included. Volume III contains some of the assessments performed by LANL and FzK

  17. 6, 42134249, 2006 Organic aerosols in

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ACPD 6, 4213­4249, 2006 Organic aerosols in the Northeastern Pacific K. K. Crahan et al. Title Page Chemistry and Physics Discussions Organics in the Northeastern Pacific and their impacts on aerosol Organic aerosols in the Northeastern Pacific K. K. Crahan et al. Title Page Abstract Introduction

  18. 6, 93519388, 2006 Aerosol-cloud

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ACPD 6, 9351­9388, 2006 Aerosol-cloud interaction inferred from MODIS and models G. Myhre et al Chemistry and Physics Discussions Aerosol-cloud interaction inferred from MODIS satellite data and global 6, 9351­9388, 2006 Aerosol-cloud interaction inferred from MODIS and models G. Myhre et al. Title

  19. The impact of detailed urbanscale processing on the composition, distribution, and radiative forcing of anthropogenic aerosols

    E-Print Network [OSTI]

    forcing of anthropogenic aerosols Jason Blake Cohen,1,2 Ronald G. Prinn,1 and Chien Wang1 Received 11 model to simulate the effects of cities around the world on aerosol chemistry, physics, and radiative values of total aerosol surface concentration, the total aerosol column abundance, the aerosol optical

  20. aerosol characteristic researching: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    as they have significant impacts both on localregional air pollution and global climate. Recent for Aerosol and Cloud Chemistry, Aerodyne Research, Incorporated, Billerica,...

  1. Formation of ozone and growth of aerosols in young smoke plumes from biomass burning: 1. Lagrangian parcel studies

    E-Print Network [OSTI]

    Alvarado, Matthew James

    We have developed a new model of the gas- and aerosol-phase chemistry of biomass burning smoke plumes called Aerosol Simulation Program (ASP). Here we use ASP combined with a Lagrangian parcel model to simulate the chemistry ...

  2. Aerosol engineering: design and stability of aerosol reactors

    SciTech Connect (OSTI)

    Pratsinis, S.E.

    1985-01-01T23:59:59.000Z

    A theoretical study of the performance of aerosol reactors is presented. The goals of this study are (1) to identify the appropriate reactor types (batch, CSTR, and tubular) for production of aerosol with specific properties (for example, uniform size particles, high aerosol surface area, etc.) and (2) to investigate the effect of various process parameters on product aerosol characteristics and on the stability of operation of aerosol reactors. In all the reactors considered, the aerosol dynamics were detemined by chemical reaction, nucleation, and aerosol growth in the free molecule regime in the absence of coagulation at isothermal conditions. Formulation of the aerosol dynamics in terms of moments of the aerosol size distribution facilitated the numerical solution of the resulting systems of ordinary or partial differential equations. The stability characteristics of a continuous stirred tank aerosol reactor (CSTAR) were investigated since experimental data in the literature indicate that under certain conditions this reactor exhibits oscillatory behavior with respect to product aerosol concentration and size distribution.

  3. Emission and Chemistry of Organic Carbon in the Gas and Aerosol Phase at a Sub-Urban Site Near Mexico City in March 2006 During the MILAGRO Study

    SciTech Connect (OSTI)

    de Gouw, Joost A.; Welsh-Bon, Daniel; Warneke, Carsten; Kuster, W. C.; Alexander, M. L.; Baker, Angela K.; Beyersdorf, Andreas J.; Blake, D. R.; Canagaratna, Manjula R.; Celada, A. T.; Huey, L. G.; Junkermann, W.; Onasch, Timothy B.; Salcido, A.; Sjostedt, S. J.; Sullivan, Amy; Tanner, David J.; Vargas-Ortiz, Leroy; Weber, R. J.; Worsnop, Douglas R.; Yu, Xiao-Ying; Zaveri, Rahul A.

    2009-05-28T23:59:59.000Z

    Volatile organic compounds (VOCs) and carbonaceous aerosol were measured at a sub-urban site near Mexico City in March of 2006 during the MILAGRO study (Megacity Initiative: Local and Global Research Objectives). Diurnal variations of hydrocarbons, elemental carbon (EC) and hydrocarbon-like organic aerosol (HOA) were dominated by a high peak in the early morning when local emissions accumulated in a shallow boundary layer, and a minimum in the afternoon when the emissions were diluted in a significantly expanded boundary layer and, in case of the reactive gases, removed by OH. In comparison, diurnal variations of species with secondary sources such as the aldehydes, ketones, oxygenated organic aerosol (OOA) and water-soluble organic carbon (WSOC) stayed relatively high in the afternoon indicating strong photochemical formation. Emission ratios of many hydrocarbon species relative to CO were higher in Mexico City than in the U.S., but we found similar emission ratios for most oxygenated VOCs and organic aerosol. Secondary formation of acetone may be more efficient in Mexico City than in the U.S., due to higher emissions of alkane precursors from the use of liquefied petroleum gas. Secondary formation of organic aerosol was similar between Mexico City and the U.S. Combining the data for all measured gas and aerosol species, we describe the budget of total observed organic carbon (TOOC), and find that the enhancement ratio of TOOC relative to CO is conserved between the early morning and mid afternoon despite large compositional changes. Finally, the influence of biomass burning is investigated using the measurements of acetonitrile, which was found to correlate with levoglucosan in the particle phase. Diurnal variations of acetonitrile indicate a contribution from local burning sources. Scatter plots of acetonitrile versus CO suggest that the contribution of biomass burning to the enhancement of most gas and aerosol species was not dominant and perhaps not dissimilar from observations in the U.S.

  4. Where do particulate toxins reside? An improved paradigm for the structure and dynamics of the urban mid-Atlantic aerosol

    SciTech Connect (OSTI)

    Ondov, J.M. [Univ. of Maryland, College Park, MD (United States). Dept. of Chemistry and Biochemistry] [Univ. of Maryland, College Park, MD (United States). Dept. of Chemistry and Biochemistry; Wexler, A.S. [Univ. of Delaware, Newark, DE (United States). Dept. of Mechanical Engineering] [Univ. of Delaware, Newark, DE (United States). Dept. of Mechanical Engineering

    1998-09-01T23:59:59.000Z

    Discussions of excess mortality and morbidity from exposure to urban aerosol particles typically invoke the now 20-year-old trimodal aerosol paradigm proposed by Whitby to explain the structure and behavior of ambient aerosol volume and its major constituent, sulfate. However, this paradigm largely ignores the primary high-temperature combustion (HTC) components of the urban aerosol, which contribute minor amounts of the aerosol mass, but carry the bulk of the particulate toxins and numbers of aerosol particles. Studies encompassing the analyses of >100 size distributions of important intrinsic tracers of primary particles from HTC sources collected over the past decade in various environments show that urban aerosol contains a complex mixture of physically-discrete fresh and aged, primary particle populations from a variety of sources. Furthermore, whereas the behavior of fine-particulate aerosol mass and sulfate was described in terms of coagulation and accumulation aerosol scavenging of new secondary sulfate nuclei, studies reviewed herein suggest that the behavior of primary aerosol is mediated more by hygroscopic growth and cloud processing, accompanied by oxidation of SO{sub 2} on wet particles and droplets. The authors conclude that the distribution of airborne particulate toxins and their atmospheric behavior is far more complex than commonly conceptualized on the basis of the classical trimodal model, and they develop an extended paradigm in which the focus is on the primary accumulation aerosol.

  5. The use of dynamic adaptive chemistry in combustion simulation of gasoline surrogate fuels

    SciTech Connect (OSTI)

    Liang, Long; Raman, Sumathy; Farrell, John T. [Corporate Strategic Research Laboratories, ExxonMobil Research and Engineering Company, 1545 Route 22 East, Annandale, NJ 08801 (United States); Stevens, John G. [Corporate Strategic Research Laboratories, ExxonMobil Research and Engineering Company, 1545 Route 22 East, Annandale, NJ 08801 (United States); Department of Mathematical Sciences, Montclair State University, Montclair, NJ 07043 (United States)

    2009-07-15T23:59:59.000Z

    A computationally efficient dynamic adaptive chemistry (DAC) scheme is described that permits on-the-fly mechanism reduction during reactive flow calculations. The scheme reduces a globally valid full mechanism to a locally, instantaneously applicable smaller mechanism. Previously we demonstrated its applicability to homogeneous charge compression ignition (HCCI) problems with n-heptane [L. Liang, J.G. Stevens, J.T. Farrell, Proc. Combust. Inst. 32 (2009) 527-534]. In this work we demonstrate the broader utility of the DAC scheme through the simulation of HCCI and shock tube ignition delay times (IDT) for three gasoline surrogates, including two- and three-component blends of primary reference fuels (PRF) and toluene reference fuels (TRF). Both a detailed 1099-species mechanism and a skeletal 150-species mechanism are investigated as the full mechanism to explore the impact of fuel complexity on the DAC scheme. For all conditions studied, pressure and key species profiles calculated using the DAC scheme are in excellent agreement with the results obtained using the full mechanisms. For the HCCI calculations using the 1099- and 150-species mechanisms, the DAC scheme achieves 70- and 15-fold CPU time reductions, respectively. For the IDT problems, corresponding speed-up factors of 10 and two are obtained. Practical guidance is provided for choosing the search-initiating species set, selecting the threshold, and implementing the DAC scheme in a computational fluid dynamics (CFD) framework. (author)

  6. Secondary Organic Aerosol Formation From the Heterogeneous Chemistry of Isoprene-Derived Epoxides: Implications for Air Quality, Climate and Public Health

    E-Print Network [OSTI]

    Lin, Qiao

    through aerosol-cloud interactions, and is associated with adverse effects on human health. Globally Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel.5 µm) impacts Earth's climate directly through scattering/absorbing solar radiation and indirectly

  7. Assessment of the Upper Particle Size Limit for Quantitative Analysis of Aerosols Using

    E-Print Network [OSTI]

    Hahn, David W.

    the vaporization dynamics of individual aerosol particles, such as thermophoretic forces and vapor expulsion. Since

  8. Department of Chemistry "Supramolecular Chemistry in Polymeric

    E-Print Network [OSTI]

    Mark, James E.

    Department of Chemistry "Supramolecular Chemistry in Polymeric Systems: From Nanoassemblies to Dynamic Materials" Presented by: Professor Stuart J. Rowan Case Western Reserve University Departmental Colloquium Friday, May 15, 2009 3:00 p.m. 502 Rieveschl #12;Supramolecular Chemistry in Polymeric Systems

  9. NON-EQUILIBRIUM CHEMISTRY OF DYNAMICALLY EVOLVING PRESTELLAR CORES. II. IONIZATION AND MAGNETIC FIELD

    SciTech Connect (OSTI)

    Tassis, Konstantinos; Willacy, Karen; Yorke, Harold W.; Turner, Neal J. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

    2012-07-20T23:59:59.000Z

    We study the effect that non-equilibrium chemistry in dynamical models of collapsing molecular cloud cores has on measurements of the magnetic field in these cores, the degree of ionization, and the mean molecular weight of ions. We find that OH and CN, usually used in Zeeman observations of the line-of-sight magnetic field, have an abundance that decreases toward the center of the core much faster than the density increases. As a result, Zeeman observations tend to sample the outer layers of the core and consistently underestimate the core magnetic field. The degree of ionization follows a complicated dependence on the number density at central densities up to 10{sup 5} cm{sup -3} for magnetic models and 10{sup 6} cm{sup -3} in non-magnetic models. At higher central densities, the scaling approaches a power law with a slope of -0.6 and a normalization which depends on the cosmic-ray ionization rate {zeta} and the temperature T as ({zeta}T){sup 1/2}. The mean molecular weight of ions is systematically lower than the usually assumed value of 20-30, and, at high densities, approaches a value of 3 due to the asymptotic dominance of the H{sup +}{sub 3} ion. This significantly lower value implies that ambipolar diffusion operates faster.

  10. 6, 75197562, 2006 Simulating aerosol

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , particle number concentration and aerosol size-distribution. The model takes into account sulfate (SO4. This model system enables explicit simulations of the particle number concentration and size-distribution of aerosol dynamical processes (nucleation, condensation, coagulation) is evaluated by comparison

  11. Chemical Dynamics, Molecular Energetics, and Kinetics at the Synchrotron

    SciTech Connect (OSTI)

    Leone, Stephen R.; Ahmed, Musahid; Wilson, Kevin R.

    2010-03-14T23:59:59.000Z

    Scientists at the Chemical Dynamics Beamline of the Advanced Light Source in Berkeley are continuously reinventing synchrotron investigations of physical chemistry and chemical physics with vacuum ultraviolet light. One of the unique aspects of a synchrotron for chemical physics research is the widely tunable vacuum ultraviolet light that permits threshold ionization of large molecules with minimal fragmentation. This provides novel opportunities to assess molecular energetics and reaction mechanisms, even beyond simple gas phase molecules. In this perspective, significant new directions utilizing the capabilities at the Chemical Dynamics Beamline are presented, along with an outlook for future synchrotron and free electron laser science in chemical dynamics. Among the established and emerging fields of investigations are cluster and biological molecule spectroscopy and structure, combustion flame chemistry mechanisms, radical kinetics and product isomer dynamics, aerosol heterogeneous chemistry, planetary and interstellar chemistry, and secondary neutral ion-beam desorption imaging of biological matter and materials chemistry.

  12. 147Chemistry Chemistry (Chem)

    E-Print Network [OSTI]

    Dresden, Gregory

    147Chemistry Chemistry (Chem) Bayly Foundation PROFESSORS FRANCE, PLEVA ASSOCIATE PROFESSORS ALty A student may complete only one of the majors listed in the Department of Chemistry. The major in chemistry leading to a Bachelor of Arts degree requires completion of 44 credits as follows: 1. Chemistry 111, 112

  13. Aerosol Science and Technology, 44:329338, 2010 Copyright American Association for Aerosol Research

    E-Print Network [OSTI]

    Dabdub, Donald

    for Photochemical and Thermal Studies of Tropospheric Aerosols Michael J. Ezell,1 Stanley N. Johnson,1 Yong Yu,2 V of the UCI Physical Sciences Machine Shop; and J¨org Meyer of the UCI Chemistry Department Glassblow- ing

  14. Do biomass burning aerosols intensify drought in equatorial Asia during El Nińo?

    E-Print Network [OSTI]

    Tosca, M. G; Randerson, J. T; Zender, C. S; Flanner, M. G; Rasch, P. J

    2010-01-01T23:59:59.000Z

    fication of drought-induced biomass burning in Indonesiavariability in global biomass burning emissions from 1997 toChemistry and Physics Do biomass burning aerosols intensify

  15. Separating real and apparent effects of cloud, humidity, and dynamics on aerosol optical thickness near cloud edges

    E-Print Network [OSTI]

    Li, Zhanqing

    have reported correlations between AOT and cloud cover, pointing to potential cloud contamination of Energy's Atmospheric Radiation Measurement Program. It was found that aerosol humidification effects can explain about one fourth of the correlation between the cloud cover and AOT. New particle genesis

  16. The Transformation of Solid Atmospheric Particles into Liquid Droplets Through Heterogeneous Chemistry: Laboratory Insights into the Processing of Calcium Containing Mineral Dust Aerosol in the Troposphere

    SciTech Connect (OSTI)

    Krueger, Brenda J.; Grassian, Vicki H.; Laskin, Alexander; Cowin, James P.

    2003-02-15T23:59:59.000Z

    [1] Individual calcium carbonate particles reacted with gas- phase nitric acid at 293 K have been followed using Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray (EDX) analysis as a function of time and relative humidity (RH). The rate of calcium carbonate to calcium nitrate conversion is significantly enhanced in the presence of water vapor. The SEM images clearly show that solid CaCO3 particles are converted to spherical droplets as the reaction proceeds. The process occurs through a two-step mechanism involving the conversion of calcium carbonate into calcium nitrate followed by the deliquescence of the calcium nitrate product. The change in phase of the particles and the significant reactivity of nitric acid and CaCO3 at low RH are a direct result of the deliquescence of the product at low RH. This is the first laboratory study to show the phase transformation of solid particles into liquid droplets through heterogeneous chemistry.

  17. COBRA: A Computational Brewing Application for Predicting the Molecular Composition of Organic Aerosols

    E-Print Network [OSTI]

    Nizkorodov, Sergey

    Aerosols David R. Fooshee,, Tran B. Nguyen,§, Sergey A. Nizkorodov,*,§ Julia Laskin, Alexander Laskin aerosols (OA) represent a significant fraction of airborne particulate matter and can impact climate insignificant. COBRA is not limited to atmospheric aerosol chemistry; it should be applicable to the prediction

  18. Direct radiative effect of aerosols emitted by transport from road, shipping and

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    Direct radiative effect of aerosols emitted by transport from road, shipping and aviation 1234567.0 License. Atmospheric Chemistry and Physics Direct radiative effect of aerosols emitted by transport: from ­ Published: 17 May 2010 Abstract. Aerosols and their precursors are emitted abun- dantly by transport

  19. Chemistry and dynamics of SF6 injections into the F region

    SciTech Connect (OSTI)

    Bernhardt, P.A.

    1984-06-01T23:59:59.000Z

    The chemistry of SF6 vapor reacting in the F region is critically examined. The SF6 molecule dissociatively attaches an electron, producing the SF5 ion. Reaction between an ambient O ion and the SF5 yields mutual neutralization. During the neutralization process, an electronically excited oxygen atom, O( D), may be produced which will subsequently emit a 630.0-nm photon. A release of 20 kg of SF6 into an ambient O ion concentration of 10V cm T at 300-km altitude is considered. The 630.0-nm airglow intensity may increase following the release. The negative ion plasma is shown to be marginally unstable to a gradient drift instability. 37 references, 7 figures, 4 tables.

  20. Quantifying the Reactive Uptake of OH by Organic Aerosols in aContinuous Flow Stirred Tank Reactor

    SciTech Connect (OSTI)

    Che, Dung L.; Smith, Jared D.; Leone, Stephen R.; Ahmed, Musahid; Wilson, Kevin R.

    2009-03-01T23:59:59.000Z

    Here we report a new method for measuring the heterogeneous chemistry of submicron organic aerosol particles using a continuous flow stirred tank reactor. This approach is designed to quantify the real time heterogeneous kinetics, using a relative rate method, under conditions of low oxidant concentration and long reaction times that more closely mimic the real atmosphere. A general analytical expression, which couples the aerosol chemistry with the flow dynamics in the chamber is developed and applied to the heterogeneous oxidation of squalane particles by hydroxyl radicals (OH) in the presence of O2. The particle phase reaction is monitored via photoionization aerosol mass spectrometry and yields a reactive uptake coefficient of 0.51+-0.10, using OH concentrations of 1-7x108 molec cdot cm-3 and reaction times of 1.5+-3 hours. This uptake coefficient is larger than that found for the reaction carried out under high OH concentrations (~;;1x1010 molec cdot cm-3) and short reaction times in a flow tube reactor. This difference suggests that oxidant concentration and reaction time are not interchangeable quantities in reactions of organic aerosols with radicals. In general, this approach provides a new way to examine how the chemical aging of organic particles measured at short reaction times and high oxidant concentrations in flow tubes might differ from the long reaction times and low oxidant levels found in the real atmosphere.

  1. Aerosol Cans? -Aerosol cans use a pressurized

    E-Print Network [OSTI]

    Jia, Songtao

    WHAT TO DO WITH... Aerosol Cans? -Aerosol cans use a pressurized propellant to distribute the product. Propellants are often flammable and/or toxic. Therefore, never store aerosol cans near ignition aerosol cans must be disposed of as hazardous waste. PROPER SAFETY EQUIPMENT Safety Glasses - Proper eye

  2. aerosol cfd model: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of aerosol dynamics in the atmosphere. The approach taken represents the particle size distribution as the superposition of three lognormal subdistributions, called modes....

  3. aerosol particles originating: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of aerosol dynamics in the atmosphere. The approach taken represents the particle size distribution as the superposition of three lognormal subdistributions, called modes....

  4. aerosol infection model: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of aerosol dynamics in the atmosphere. The approach taken represents the particle size distribution as the superposition of three lognormal subdistributions, called modes....

  5. Extending the Artificial Chemistry to Design Networking Algorithms with Controllable Dynamics

    E-Print Network [OSTI]

    Vetter, Thomas

    networking algorithms which exhibit predictable dynamics. More specifically in a bottom-up manner, we design Massimo Monti, Manolis Sifalakis, Christian F. Tschudin Technical Report CS-2012-003 University of Basel, exhibit predictable behaviors emerging from the un- derlying models. Our approach to design algorithms

  6. 148 Chemistry/Chinese Chemistry 347 (3)--Advanced Organic Chemistry

    E-Print Network [OSTI]

    Dresden, Gregory

    148 Chemistry/Chinese Chemistry 347 (3)--Advanced Organic Chemistry Prerequisite: Chemistry 242,syntheticmethodology,mod- ernsyntheticreactions,protectinggroups,naturalprod- uctssynthesis,andcombinatorialchemistry.France. Spring Chemistry 350 (3)--Advanced Inorganic Chemistry Prerequisites: Chemistry 250, 252, and 262. Anintro

  7. Uncertainties and Frontiers in Aerosol Research

    E-Print Network [OSTI]

    ;Transport Power Industry Biomass burning Residential Human activity Perspective Aerosol Sources (rather than, Mixing, Chemistry, Climate) Climate Effects Resource: AeroCom, an international model intercomparison of fossil fuel (coal, oil, diesel, gasoline), domestic wood burning, forest fires #12;Natural sources

  8. 8, 32273285, 2008 Aerosol DRE in Po

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    in turn reducing cloud cover by heating the lower atmosphere (the semi-direct effect, Hansen et al., 1997 Chemistry and Physics Discussions Aerosol direct radiative effect in the Po Valley region derived from direct radiative effect (ADRE) affecting the Po Valley and the adjacent North Adriatic Sea is studied

  9. Group Report: Connections between Aerosol Properties

    E-Print Network [OSTI]

    increases absorption of solar radiation in clouds. The net effect is expected to be enhancement of shortwave effect and causes surface warming. Absorption of solar or thermal radiation within the atmospheric column after cloud evaporation. 3. Indirect effects ofaerosols on heterogeneous atmospheric chemistry. Aerosol

  10. Combustion chemistry

    SciTech Connect (OSTI)

    Brown, N.J. [Lawrence Berkeley Laboratory, CA (United States)

    1993-12-01T23:59:59.000Z

    This research is concerned with the development and use of sensitivity analysis tools to probe the response of dependent variables to model input variables. Sensitivity analysis is important at all levels of combustion modeling. This group`s research continues to be focused on elucidating the interrelationship between features in the underlying potential energy surface (obtained from ab initio quantum chemistry calculations) and their responses in the quantum dynamics, e.g., reactive transition probabilities, cross sections, and thermal rate coefficients. The goals of this research are: (i) to provide feedback information to quantum chemists in their potential surface refinement efforts, and (ii) to gain a better understanding of how various regions in the potential influence the dynamics. These investigations are carried out with the methodology of quantum functional sensitivity analysis (QFSA).

  11. Atmospheric Chemistry

    E-Print Network [OSTI]

    Finlayson-Pitts, B. J

    2010-01-01T23:59:59.000Z

    in our understanding of important chemistry and highlightedin our knowledge. In summary, the chemistry occurring in theBJ, Pitts JN, Jr (2000) Chemistry of the Upper and Lower

  12. CLUSTER CHEMISTRY

    E-Print Network [OSTI]

    Muetterties, Earl L.

    2013-01-01T23:59:59.000Z

    Advanced Inorganic Chemistry, 11 Wiley Huetterties and C. M.Submitted to the Journal of Organometallic ChemistryCLUSTER CHEMISTRY Earl L. Muetterties TWO-WEEK LOAN COPY May

  13. Aerosol Characterization Data from the Asian Pacific Regional Aerosol Characterization Project (ACE-Asia)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    The Aerosol Characterization Experiments (ACE) were designed to increase understanding of how atmospheric aerosol particles affect the Earth's climate system. These experiments integrated in-situ measurements, satellite observations, and models to reduce the uncertainty in calculations of the climate forcing due to aerosol particles and improve the ability of models to predict the influences of aerosols on the Earth's radiation balance. ACE-Asia was the fourth in a series of experiments organized by the International Global Atmospheric Chemistry (IGAC) Program (A Core Project of the International Geosphere Biosphere Program). The Intensive Field Phase for ACE-Asia took place during the spring of 2001 (mid-March through early May) off the coast of China, Japan and Korea. ACE-Asia pursued three specific objectives: 1) Determine the physical, chemical, and radiative properties of the major aerosol types in the Eastern Asia and Northwest Pacific region and investigate the relationships among these properties. 2) Quantify the physical and chemical processes controlling the evolution of the major aerosol types and in particular their physical, chemical, and radiative properties. 3) Develop procedures to extrapolate aerosol properties and processes from local to regional and global scales, and assess the regional direct and indirect radiative forcing by aerosols in the Eastern Asia and Northwest Pacific region [Edited and shortened version of summary at http://data.eol.ucar.edu/codiac/projs?ACE-ASIA]. The Ace-Asia collection contains 174 datasets.

  14. Fluxes, dynamics and chemistry of suspended particulate matter in a southeast Alaskan fjord

    SciTech Connect (OSTI)

    Hong, G.H.

    1986-01-01T23:59:59.000Z

    The weighted mean fluxes over the June 1982-October 1983 were 290, 519, 812, 1124 g m/sup -2/ yr/sup -1/, respectively, determined using sediment traps deployed at 40, 120, 300 and 375 m depth in the 380 m water column. The long-term sedimentation rate was estimated at average 589 g m/sup -2/ yr/sup -1/ from sediment /sup 210/Pb profiles. Substantial SPM input to mid-depths (below 100 m) from the side arms was noted. Thus, the flux measured at 120 m depth was designated as the primary flux of the SPM to the basin. The sediment focusing resulting from the V shaped basin does not appear to be important. Using particulate Al as a tracer, resuspension rate was estimated at some 30-80% of the vertical flux below 280 m depth. Based on the SPM dynamics, the non-conservative behavior of particulate biogenic matter, Mn and Fe was investigated using a primary-resuspended-altered flux model.

  15. THE ROLE OF SOOT IN AEROSOL CHEMISTRY

    E-Print Network [OSTI]

    Novakov, T.

    2010-01-01T23:59:59.000Z

    of Energy under Contract W-7405-ENG-48 Office of Health andEnergy under contract no. W-7405-ENG-48 and by the NationalEnergy under contract no. W-7405-ENG-48. and by the National

  16. Aerosol and Aqueous Chemistry Equilibrium Partitioning

    E-Print Network [OSTI]

    Russell, Lynn

    that came into contact with it condensed into a fog bank, which the light winds pushed up into a layer to have been around pH 1.4 - 1.9, which is more acidic than lemon juice and almost as acidic car battery eastwards and out over the Dogger Bank. · The Times newspaper recorded the single loss of life during

  17. Modeling kinetic partitioning of secondary organic aerosol and size distribution dynamics: representing effects of volatility, phase state, and particle-phase reaction

    SciTech Connect (OSTI)

    Zaveri, Rahul A.; Easter, Richard C.; Shilling, John E.; Seinfeld, J. H.

    2014-05-27T23:59:59.000Z

    Evidence is mounting that the majority of the climatically active aerosols are produced through the growth of smaller particles via secondary organic aerosol (SOA) formation from gas-to-particle conversion of anthropogenic and biogenic volatile organic compounds (VOCs). The timescale of SOA partitioning and the associated size distribution dynamics are expected to depend on the gas-phase oxidation of the precursor VOCs and their products, volatility of these organic solutes, composition and phase state of the pre-existing particles, and diffusivity and reactivity of the solute within the particle phase. This paper describes a new framework for modeling kinetic gas-particle partitioning of SOA, with an analytical treatment for the diffusion-reaction process within the particle phase. The formulation is amenable for eventual use in regional and global climate models, although it currently awaits implementation of the actual particle-phase reactions that are important for SOA formation. In the present work, the model is applied to investigate the competitive growth dynamics of the Aitken and accumulation mode particles while the Kelvin effect and coagulation are neglected for simplicity. The timescale of SOA partitioning and evolution of number and composition size distributions are evaluated for a range of solute volatilities (C*), particle-phase bulk diffusivities (Db), and particle-phase reactivity, as exemplified by a pseudo-first-order rate constant (kc). Results show that irreversible condensation of non-volatile organic vapors (equivalent to ) produces significant narrowing of the size distribution. At the other extreme, non-reactive partitioning of semi-volatile organic vapors is volume-controlled in which the final (equilibrium) size distribution simply shifts to the right on the diameter axis while its shape remains unchanged. However, appreciable narrowing of the size distribution may occur when the pre-existing particles are highly viscous semi-solids such that small particles reach quasi-equilibrium much faster than the large ones. In the case of reactive partitioning (finite ), the size distribution experiences permanent narrowing, which is especially pronounced for Db < 10-13 cm2 s-1 and kc > 0.01 s-1. As a result, both number and composition size distributions are needed to effectively constrain and evaluate the next generation of SOA models that treat phase state thermodynamics, particle-phase diffusion and particle-phase chemical reactions.

  18. Aerosol Science and Technology, 47:818830, 2013 Copyright C American Association for Aerosol Research

    E-Print Network [OSTI]

    chemical components are affected by in-canopy chemistry, vertical gradients in gas-particle Received 17 secondary organic aerosol (SOA) emitted. During BEARPEX-07, rapid in- canopy oxidation caused rapid SOA, and thermal shifts in gas-particle partitioning. Wet deposition was estimated to be an order of magnitude

  19. aerosols | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Molecular Science Computing Facility: Quiet Wing Science Theme: Biosystem Dynamics & Design Terrestrial & Subsurface Ecosystems Energy Materials & Processes Atmospheric...

  20. Organic Aerosol Component (OACOMP) Value-Added Product Report

    SciTech Connect (OSTI)

    Fast, J; Zhang, Q; Tilp, A; Shippert, T; Parworth, C; Mei, F

    2013-08-23T23:59:59.000Z

    Significantly improved returns in their aerosol chemistry data can be achieved via the development of a value-added product (VAP) of deriving OA components, called Organic Aerosol Components (OACOMP). OACOMP is primarily based on multivariate analysis of the measured organic mass spectral matrix. The key outputs of OACOMP are the concentration time series and the mass spectra of OA factors that are associated with distinct sources, formation and evolution processes, and physicochemical properties.

  1. Speciation of Fe in ambient aerosol and cloudwater

    SciTech Connect (OSTI)

    Siefert, L. [California Institute of Technology, Pasadena, CA (United States)

    1996-08-15T23:59:59.000Z

    Atmospheric iron (Fe) is thought to play an important role in cloudwater chemistry (e.g., S(IV) oxidation, oxidant production, etc.), and is also an important source of Fe to certain regions of the worlds oceans where Fe is believed to be a rate-limiting nutrient for primary productivity. This thesis focuses on understanding the chemistry, speciation and abundance of Fe in cloudwater and aerosol in the troposphere, through observations of Fe speciation in the cloudwater and aerosol samples collected over the continental United States and the Arabian Sea. Different chemical species of atmospheric Fe were measured in aerosol and cloudwater samples to help assess the role of Fe in cloudwater chemistry.

  2. Formation of ozone and growth of aerosols in young smoke plumes from biomass burning

    E-Print Network [OSTI]

    Alvarado, Matthew James

    2008-01-01T23:59:59.000Z

    The combustion of biomass is a major source of atmospheric trace gases and aerosols. Regional and global-scale models of atmospheric chemistry and climate take estimates for these emissions and arbitrarily "mix" them into ...

  3. The aging of organic aerosol in the atmosphere : chemical transformations by heterogeneous oxidation

    E-Print Network [OSTI]

    Kessler, Sean Herbert

    2013-01-01T23:59:59.000Z

    The immense chemical complexity of atmospheric organic particulate matter ("aerosol") has left the general field of condensed-phase atmospheric organic chemistry relatively under-developed when compared with either gas-phase ...

  4. Aerosol collection characteristics of ambient aerosol samplers

    E-Print Network [OSTI]

    Ortiz, Carlos A

    1978-01-01T23:59:59.000Z

    are contained in Appendix C. Dichotomous Sam ler The basic principle of operation of the dichotomous, Figure 9, is that aerosol particles are passed through an acceleration nozzle where the particle velocity is increased to a speed V. at the nozzle exit... AEROSOL COLLECTION CHARACTERISTICS OF AMBIENT AEROSOL SAMPLERS A Thesis by CARLOS A. ORTIZ Submitted to the Graduate College of Texas ARM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE December 1978...

  5. Aerosol mobility size spectrometer

    DOE Patents [OSTI]

    Wang, Jian (Port Jefferson, NY); Kulkarni, Pramod (Port Jefferson Station, NY)

    2007-11-20T23:59:59.000Z

    A device for measuring aerosol size distribution within a sample containing aerosol particles. The device generally includes a spectrometer housing defining an interior chamber and a camera for recording aerosol size streams exiting the chamber. The housing includes an inlet for introducing a flow medium into the chamber in a flow direction, an aerosol injection port adjacent the inlet for introducing a charged aerosol sample into the chamber, a separation section for applying an electric field to the aerosol sample across the flow direction and an outlet opposite the inlet. In the separation section, the aerosol sample becomes entrained in the flow medium and the aerosol particles within the aerosol sample are separated by size into a plurality of aerosol flow streams under the influence of the electric field. The camera is disposed adjacent the housing outlet for optically detecting a relative position of at least one aerosol flow stream exiting the outlet and for optically detecting the number of aerosol particles within the at least one aerosol flow stream.

  6. Point and column aerosol radiative closure during ACE 1: Effects of particle shape and size

    E-Print Network [OSTI]

    impact the earth's climate and photo- chemistry by directly scattering and absorbing solar radia- tion these impacts [e.g., Intergovernmental Panel on Climate Change, 2001]. Because of the short temporal and spatial scales of aerosol heterogeneity, numerical models of aerosol optical behavior are required to make

  7. Environmental Chemistry II (Atmospheric Chemistry)

    E-Print Network [OSTI]

    Dibble, Theodore

    SYLLABUS FOR Environmental Chemistry II (Atmospheric Chemistry) FCH 511 Fall 2013 Theodore S/explaining the trends in J as a function of altitude and solar zenith angle. The second involves analyzing real

  8. Modeling aerosols and their interactions with shallow cumuli during the 2007 CHAPS field study

    SciTech Connect (OSTI)

    Shrivastava, ManishKumar B.; Berg, Larry K.; Fast, Jerome D.; Easter, Richard C.; Laskin, Alexander; Chapman, Elaine G.; Gustafson, William I.; Liu, Ying; Berkowitz, Carl M.

    2013-02-07T23:59:59.000Z

    The Weather Research and Forecasting model coupled with chemistry (WRF-Chem) is used to simulate relationships between aerosols and clouds in the vicinity of Oklahoma City during the June 2007 Cumulus Humilis Aerosol Processing Study (CHAPS). The regional scale simulation completed using 2 km horizontal grid spacing evaluates four important relationships between aerosols and shallow cumulus clouds observed during CHAPS. First, the model reproduces the trends of higher nitrate volume fractions in cloud droplet residuals compared to interstitial non-activated aerosols, as measured using the Aerosol Mass Spectrometer. Comparing simulations with cloud chemistry turned on and off, we show that nitric acid vapor uptake by cloud droplets explains the higher nitrate content of cloud droplet residuals. Second, as documented using an offline code, both aerosol water and other inorganics (OIN), which are related to dust and crustal emissions, significantly affect predicted aerosol optical properties. Reducing the OIN content of wet aerosols by 50% significantly improves agreement of model predictions with measurements of aerosol optical properties. Third, the simulated hygroscopicity of aerosols is too high as compared to their hygroscopicity derived from cloud condensation nuclei and particle size distribution measurements, indicating uncertainties associated with simulating size-dependent chemical composition and treatment of aerosol mixing state within the model. Fourth, the model reasonably represents the observations of the first aerosol indirect effect where pollutants in the vicinity of Oklahoma City increase cloud droplet number concentrations and decrease the droplet effective radius. While previous studies have often focused on cloud-aerosol interactions in stratiform and deep convective clouds, this study highlights the ability of regional-scale models to represent some of the important aspects of cloud-aerosol interactions associated with fields of short-lived shallow cumuli.

  9. Studies of dynamical processes affecting global climate

    SciTech Connect (OSTI)

    Keller, C.; Cooper, D.; Eichinger, W. [and others

    1998-12-31T23:59:59.000Z

    This is the final report of a three-year, Laboratory Directed Research and Development project at the Los Alamos National Laboratory (LANL). The main objective was, by a combined theoretical and observational approach, to develop improved models of dynamic processes in the oceans and atmosphere and to incorporate them into large climate codes, chiefly in four main areas: numerical physics, chemistry, water vapor, and ocean-atmosphere interactions. Main areas of investigation included studies of: cloud parameterizations for global climate codes, Lidar and the planetary boundary layer, chemistry, climate variability using coupled ocean-atmospheric models, and numerical physical methods. This project employed a unique approach that included participation of a number of University of California faculty, postdoctoral fellows and graduate students who collaborated with Los Alamos research staff on specific tasks, thus greatly enhancing the research output. Overall accomplishments during the sensing of the atmospheric planetary were: (1) first two- and three-dimensional remote sensing of the atmospheric planetary boundary layer using Lidars, (2) modeling of 20-year cycle in both pressure and sea surface temperatures in North Pacific, (3) modeling of low frequency internal variability, (4) addition of aerosols to stratosphere to simulate Pinatubo effect on ozone, (5) development of fast, comprehensive chemistry in the troposphere for urban pollution studies, (6) new prognostic cloud parameterization in global atmospheric code remedied problems with North Pacific atmospheric circulation and excessive equatorial precipitation, (7) development of a unique aerosol analysis technique, the aerosol time-of-flight mass spectrometer (ATOFMS), which allows real-time analysis of the size and chemical composition of individual aerosol particles, and (8) numerical physics applying Approximate Inertial Manifolds to ocean circulation. 14 refs., 6 figs.

  10. Organophosphorus chemistry

    E-Print Network [OSTI]

    Hanson, Paul R.

    2014-09-04T23:59:59.000Z

    2087 Organophosphorus chemistry Paul R. Hanson Editorial Open Access Address: Department of Chemistry, University of Kansas, 1251 Wescoe Hall Drive, Lawrence, KS 66045-7582, USA Email: Paul R. Hanson - phanson@ku.edu. Keywords: organophosphorus... Beilstein J. Org. Chem. 2014, 10, 2087–2088. doi:10.3762/bjoc.10.217 Received: 28 July 2014 Accepted: 06 August 2014 Published: 04 September 2014 This article is part of the Thematic Series "Organophosphorus chemistry" Guest Editor: P. R. Hanson © 2014...

  11. Can aerosols be trapped in open flows?

    E-Print Network [OSTI]

    Rafael D. Vilela; Adilson E. Motter

    2008-01-22T23:59:59.000Z

    The fate of aerosols in open flows is relevant in a variety of physical contexts. Previous results are consistent with the assumption that such finite-size particles always escape in open chaotic advection. Here we show that a different behavior is possible. We analyze the dynamics of aerosols both in the absence and presence of gravitational effects, and both when the dynamics of the fluid particles is hyperbolic and nonhyperbolic. Permanent trapping of aerosols much heavier than the advecting fluid is shown to occur in all these cases. This phenomenon is determined by the occurrence of multiple vortices in the flow and is predicted to happen for realistic particle-fluid density ratios.

  12. Development and Characterization of a Thermodenuder for Aerosol Volatility Measurements

    SciTech Connect (OSTI)

    Dr. Timothy Onasch

    2009-09-09T23:59:59.000Z

    This SBIR Phase I project addressed the critical need for improved characterization of carbonaceous aerosol species in the atmosphere. The proposed work focused on the development of a thermodenuder (TD) system capable of systematically measuring volatility profiles of primary and secondary organic aerosol species and providing insight into the effects of absorbing and nonabsorbing organic coatings on particle absorption properties. This work provided the fundamental framework for the generation of essential information needed for improved predictions of ambient aerosol loadings and radiative properties by atmospheric chemistry models. As part of this work, Aerodyne Research, Inc. (ARI) continued to develop and test, with the final objective of commercialization, an improved thermodenuder system that can be used in series with any aerosol instrument or suite of instruments (e.g., aerosol mass spectrometers-AMS, scanning mobility particle sizers-SMPS, photoacoustic absorption spectrometers-PAS, etc.) to obtain aerosol chemical, physical, and optical properties as a function of particle volatility. In particular, we provided the proof of concept for the direct coupling of our improved TD design with a full microphysical model to obtain volatility profiles for different organic aerosol components and to allow for meaningful comparisons between different TD-derived aerosol measurements. In a TD, particles are passed through a heated zone and a denuding (activated charcoal) zone to remove semi-volatile material. Changes in particle size, number concentration, optical absorption, and chemical composition are subsequently detected with aerosol instrumentation. The aerosol volatility profiles provided by the TD will strengthen organic aerosol emission inventories, provide further insight into secondary aerosol formation mechanisms, and provide an important measure of particle absorption (including brown carbon contributions and identification, and absorption enhancements due to coatings on soot particles). The successfully completed Phase I project included construction of a prototype design for the TD with detailed physical modeling, testing with laboratory and ambient aerosol particles, and the initiation of a detailed microphysical model of the aerosol particles passing through the TD to extract vapor pressure distributions. The objective of the microphysical model is to derive vapor pressure distributions (i.e. vapor pressure ranges, including single chemical compounds, mixtures of known compounds, and complex ‘real-world’ aerosols, such as SOA, and soot particles with absorbing and nonabsorbing coatings) from TD measurements of changes in particle size, mass, and chemical composition for known TD temperatures and flow rates (i.e. residence times). The proposed Phase II project was designed to optimize several TD systems for different instrument applications and to combine the hardware and modeling into a robust package for commercial sales.

  13. Modeling Atmospheric Aerosols V. Rao Kotamarthi

    E-Print Network [OSTI]

    Modeling Atmospheric Aerosols V. Rao Kotamarthi and Yan Feng Climate Research Section Environmental Science Division Argonne National Laboratory #12;Outline Atmospheric Aerosols and gas phase heterogeneous reactions Regional Scales and Atmospheric Aerosols Regional Scale Aerosols: Ganges Valley Aerosol

  14. On the relationship between stratospheric aerosols and nitrogen dioxide

    SciTech Connect (OSTI)

    Mills, M.J.; Langford, A.O.; O'Leary, T.J.; Arpag, K.; Miller, H.L.; Proffitt, M.H.; Sanders, R.W.; Solomon, S. (Aeronomy Laboratory, NOAA, Boulder, CO (United States) Univ. of Colorado, Boulder (United States))

    1993-06-18T23:59:59.000Z

    The authors report measurements of stratospheric column abundances of nitrogen dioxide above the Colorado mountains during Jan, Feb, and Mar 1992, following the arrival of the aerosol loading injected by Mt. Pinatubo. The column abundance data was correlated with concurrent lidar measurements which provided vertical aerosol profiles at the same site. Chemical reactions within polar stratospheric clouds have been shown to play a major role in ozone chemistry in the polar regions, and one could ask whether such clouds at mid latitudes could play a similar role. The sulfur dioxide loading due to the volcanic eruption provides an abrupt increase in sulfuric acid aerosol surface area in mid latitude areas, providing a convenient test of this question. Column NO[sub 2] densities are observed to fall, but also found to saturate at a certain stratospheric aerosol density.

  15. MICS Asia Phase II - Sensitivity to the aerosol module

    E-Print Network [OSTI]

    Sartelet, Karine; Sportisse, Bruno

    2007-01-01T23:59:59.000Z

    In the framework of the model inter-comparison study - Asia Phase II (MICS2), where eight models are compared over East Asia, this paper studies the influence of different parameterizations used in the aerosol module on the aerosol concentrations of sulfate and nitrate in PM10. An intracomparison of aerosol concentrations is done for March 2001 using different configurations of the aerosol module of one of the model used for the intercomparison. Single modifications of a reference setup for model configurations are performed and compared to a reference case. These modifications concern the size distribution, i.e. the number of sections, and physical processes, i.e. coagulation, condensation/evaporation, cloud chemistry, heterogeneous reactions and sea-salt emissions. Comparing monthly averaged concentrations at different stations, the importance of each parameterization is first assessed. It is found that sulfate concentrations are little sensitive to sea-salt emissions and to whether condensation is computed...

  16. Journal of Photochemistry and Photobiology A: Chemistry 190 (2007) 342351 Ab initio study of exciton transfer dynamics from a coreshell

    E-Print Network [OSTI]

    and quantum dynamics approaches. The system harvests light in a broad energy range and can transfer Recent advances in the synthesis of nanostructures with con- trollable size, shape, and optical [2,3] and photovoltaics [4­10]. Quantum dots (QDs) form the foundation of many novel devices

  17. Ganges valley aerosol experiment.

    SciTech Connect (OSTI)

    Kotamarthi, V.R.; Satheesh, S.K. (Environmental Science Division); (Indian Institute of Science, Bangalore, India)

    2011-08-01T23:59:59.000Z

    In June 2011, the Ganges Valley Aerosol Experiment (GVAX) began in the Ganges Valley region of India. The objective of this field campaign is to obtain measurements of clouds, precipitation, and complex aerosols to study their impact on cloud formation and monsoon activity in the region.

  18. Direct Aerosol Forcing Uncertainty

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Mccomiskey, Allison

    Understanding sources of uncertainty in aerosol direct radiative forcing (DRF), the difference in a given radiative flux component with and without aerosol, is essential to quantifying changes in Earth's radiation budget. We examine the uncertainty in DRF due to measurement uncertainty in the quantities on which it depends: aerosol optical depth, single scattering albedo, asymmetry parameter, solar geometry, and surface albedo. Direct radiative forcing at the top of the atmosphere and at the surface as well as sensitivities, the changes in DRF in response to unit changes in individual aerosol or surface properties, are calculated at three locations representing distinct aerosol types and radiative environments. The uncertainty in DRF associated with a given property is computed as the product of the sensitivity and typical measurement uncertainty in the respective aerosol or surface property. Sensitivity and uncertainty values permit estimation of total uncertainty in calculated DRF and identification of properties that most limit accuracy in estimating forcing. Total uncertainties in modeled local diurnally averaged forcing range from 0.2 to 1.3 W m-2 (42 to 20%) depending on location (from tropical to polar sites), solar zenith angle, surface reflectance, aerosol type, and aerosol optical depth. The largest contributor to total uncertainty in DRF is usually single scattering albedo; however decreasing measurement uncertainties for any property would increase accuracy in DRF. Comparison of two radiative transfer models suggests the contribution of modeling error is small compared to the total uncertainty although comparable to uncertainty arising from some individual properties.

  19. 7, 55535593, 2007 Nitrate aerosols

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ACPD 7, 5553­5593, 2007 Nitrate aerosols today and in 2030 S. E. Bauer et al. Title Page Abstract Discussions Nitrate aerosols today and in 2030: importance relative to other aerosol species and tropospheric, 5553­5593, 2007 Nitrate aerosols today and in 2030 S. E. Bauer et al. Title Page Abstract Introduction

  20. Characterizing the formation of secondary organic aerosols

    SciTech Connect (OSTI)

    Lunden, Melissa; Black, Douglas; Brown, Nancy

    2004-02-01T23:59:59.000Z

    Organic aerosol is an important fraction of the fine particulate matter present in the atmosphere. This organic aerosol comes from a variety of sources; primary organic aerosol emitted directly from combustion process, and secondary aerosol formed in the atmosphere from condensable vapors. This secondary organic aerosol (SOA) can result from both anthropogenic and biogenic sources. In rural areas of the United States, organic aerosols can be a significant part of the aerosol load in the atmosphere. However, the extent to which gas-phase biogenic emissions contribute to this organic load is poorly understood. Such an understanding is crucial to properly apportion the effect of anthropogenic emissions in these rural areas that are sometimes dominated by biogenic sources. To help gain insight on the effect of biogenic emissions on particle concentrations in rural areas, we have been conducting a field measurement program at the University of California Blodgett Forest Research Facility. The field location includes has been used to acquire an extensive suite of measurements resulting in a rich data set, containing a combination of aerosol, organic, and nitrogenous species concentration and meteorological data with a long time record. The field location was established in 1997 by Allen Goldstein, a professor in the Department of Environmental Science, Policy and Management at the University of California at Berkeley to study interactions between the biosphere and the atmosphere. The Goldstein group focuses on measurements of concentrations and whole ecosystem biosphere-atmosphere fluxes for volatile organic compounds (VOC's), oxygenated volatile organic compounds (OVOC's), ozone, carbon dioxide, water vapor, and energy. Another important collaborator at the Blodgett field location is Ronald Cohen, a professor in the Chemistry Department at the University of California at Berkeley. At the Blodgett field location, his group his group performs measurements of the concentrations of important gas phase nitrogen compounds. Experiments have been ongoing at the Blodgett field site since the fall of 2000, and have included portions of the summer and fall of 2001, 2002, and 2003. Analysis of both the gas and particle phase data from the year 2000 show that the particle loading at the site correlates with both biogenic precursors emitted in the forest and anthropogenic precursors advected to the site from Sacramento and the Central Valley of California. Thus the particles at the site are affected by biogenic processing of anthropogenic emissions. Size distribution measurements show that the aerosol at the site has a geometric median diameter of approximately 100 nm. On many days, in the early afternoon, growth of nuclei mode particles (<20 nm) is also observed. These growth events tend to occur on days with lower average temperatures, but are observed throughout the summer. Analysis of the size resolved data for these growth events, combined with typical measured terpene emissions, show that the particle mass measured in these nuclei mode particles could come from oxidation products of biogenic emissions, and can serve as a significant route for SOA partitioning into the particle phase. During periods of each year, the effect of emissions for forest fires can be detected at the Blodgett field location. During the summer of 2002 emissions from the Biscuit fire, a large fire located in Southwest Oregon, was detected in the aerosol data. The results show that increases in particle scattering can be directly related to increased black carbon concentration and an appearance of a larger mode in the aerosol size distribution. These results show that emissions from fires can have significant impact on visibility over large distances. The results also reinforce the view that forest fires can be a significant source of black carbon in the atmosphere, which has important climate and visibility. Continuing work with the 2002 data set, particularly the combination of the aerosol and gas phase data, will continue to provide important information o

  1. NON-EQUILIBRIUM CHEMISTRY OF DYNAMICALLY EVOLVING PRESTELLAR CORES. I. BASIC MAGNETIC AND NON-MAGNETIC MODELS AND PARAMETER STUDIES

    SciTech Connect (OSTI)

    Tassis, Konstantinos; Willacy, Karen; Yorke, Harold W.; Turner, Neal J. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

    2012-07-01T23:59:59.000Z

    We combine dynamical and non-equilibrium chemical modeling of evolving prestellar molecular cloud cores and investigate the evolution of molecular abundances in the contracting core. We model both magnetic cores, with varying degrees of initial magnetic support, and non-magnetic cores, with varying collapse delay times. We explore, through a parameter study, the competing effects of various model parameters in the evolving molecular abundances, including the elemental C/O ratio, the temperature, and the cosmic-ray ionization rate. We find that different models show their largest quantitative differences at the center of the core, whereas the outer layers, which evolve slower, have abundances which are severely degenerate among different dynamical models. There is a large range of possible abundance values for different models at a fixed evolutionary stage (central density), which demonstrates the large potential of chemical differentiation in prestellar cores. However, degeneracies among different models, compounded with uncertainties induced by other model parameters, make it difficult to discriminate among dynamical models. To address these difficulties, we identify abundance ratios between particular molecules, the measurement of which would have maximal potential for discrimination among the different models examined here. In particular, we find that the ratios between NH{sub 3} and CO, NH{sub 2} and CO, and NH{sub 3} and HCO{sup +} are sensitive to the evolutionary timescale, and that the ratio between HCN and OH is sensitive to the C/O ratio. Finally, we demonstrate that measurements of the central deviation (central depletion or enhancement) of abundances of certain molecules are good indicators of the dynamics of the core.

  2. ARM: 1-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sivaraman, Chitra; Flynn, Connor

    1-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  3. ARM: 10-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Newsom, Rob; Goldsmith, John

    10-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  4. Radiative and climate impacts of absorbing aerosols

    E-Print Network [OSTI]

    Zhu, Aihua

    2010-01-01T23:59:59.000Z

    P.M. Forster (2004), The semi-direct aerosol effect: Impactof absorbing aerosols on marine stratocumulus. Q. J .2005), Global anthropogenic aerosol direct forcing derived

  5. Position: Assistant Professor of Chemistry, Physical Chemistry

    E-Print Network [OSTI]

    John Grey Position: Assistant Professor of Chemistry, Physical Chemistry Email: jkgrey@unm.edu Phone: 505.277.1658; Fax: 505.277.2609 Office: Clark Hall B70 Homepage: http://chemistry.unm.edu/faculty_web/jgrey Education B.S. in Chemistry, 1999, Michigan Technological University, Houghton, MI Ph.D. in Chemistry

  6. Green Chemistry and Workers

    E-Print Network [OSTI]

    2009-01-01T23:59:59.000Z

    J. Warner. 1998. Green Chemistry: Theory and Practice. NewNew Science, Green Chemistry and Environmental Health.abstract.html 5. American Chemistry Council. 2003. Guide to

  7. UCLA CHEMISTRY & BIOCHEMISTRY

    E-Print Network [OSTI]

    Levine, Alex J.

    UCLA CHEMISTRY & BIOCHEMISTRY ORIENTATION HANDBOOK 2012-2013 #12;Table of Contents Introduction .............................................................................................................................................2 Chemistry & Biochemistry Undergraduate Office ..................................................................................................3 Majors in Chemistry

  8. Nanomaterials from Aerosols Aerosols are suspensions of liquid or solid particles in a gas. Aerosol particles

    E-Print Network [OSTI]

    Beaucage, Gregory

    1 Nanomaterials from Aerosols Aerosols are suspensions of liquid or solid particles in a gas. Aerosol particles can range in size from molecular-scale to hundreds of microns with a typical example be synthesized by aerosol routes where precursor species are dispersed either in a vapor or in micron

  9. Actinide Chemistry

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041cloth DocumentationProducts (VAP) VAP7-0973 1 IntroductionActinide Chemistry Actinide chemistry

  10. Air Pollution Physics and Chemistry EAS 6790 Home Work Assignment No. 2, Air Pollution Meteorology: Box Model

    E-Print Network [OSTI]

    Weber, Rodney

    Air Pollution Physics and Chemistry EAS 6790 Fall 2008 Home Work Assignment No. 2, Air Pollution to interpret measurements made in Mexico City. Focus mainly on the discussions relating to nitrate aerosol

  11. Aerosol Sampler Operations Manual

    E-Print Network [OSTI]

    Fischer, Emily V.

    -1123 Laboratory FAX (916) 752-4107 Standard Operating Procedures Technical Information Document TI 201A #12;TI 201.................................................................................................................................................. 3 1.0 Weekly Maintenance ProceduresIMPROVE Aerosol Sampler Operations Manual February 10, 1997 Air Quality Group Crocker Nuclear

  12. Evaluation of the volatility basis-set approach for the simulation of organic aerosol formation in the Mexico City metropolitan area

    E-Print Network [OSTI]

    Tsimpidi, A. P.

    New primary and secondary organic aerosol modules have been added to PMCAMx, a three dimensional chemical transport model (CTM), for use with the SAPRC99 chemistry mechanism based on recent smog chamber studies. The new ...

  13. Aerosols and Clouds: In Cahoots to Change Climate

    ScienceCinema (OSTI)

    Berg, Larry

    2014-06-02T23:59:59.000Z

    Key knowledge gaps persist despite advances in the scientific understanding of how aerosols and clouds evolve and affect climate. The Two-Column Aerosol Project, or TCAP, was designed to provide a detailed set of observations to tackle this area of unknowns. Led by PNNL atmospheric scientist Larry Berg, ARM's Climate Research Facility was deployed in Cape Cod, Massachusetts for the 12-month duration of TCAP, which came to a close in June 2013. "We are developing new tools to look at particle chemistry, like our mass spectrometer used in TCAP that can tell us the individual chemical composition of an aerosol," said Berg. "Then, we'll run our models and compare it with the data that we have to make sure we're getting correct answers and make sure our climate models are reflecting the best information."

  14. Aerosols and Clouds: In Cahoots to Change Climate

    SciTech Connect (OSTI)

    Berg, Larry

    2014-03-29T23:59:59.000Z

    Key knowledge gaps persist despite advances in the scientific understanding of how aerosols and clouds evolve and affect climate. The Two-Column Aerosol Project, or TCAP, was designed to provide a detailed set of observations to tackle this area of unknowns. Led by PNNL atmospheric scientist Larry Berg, ARM's Climate Research Facility was deployed in Cape Cod, Massachusetts for the 12-month duration of TCAP, which came to a close in June 2013. "We are developing new tools to look at particle chemistry, like our mass spectrometer used in TCAP that can tell us the individual chemical composition of an aerosol," said Berg. "Then, we'll run our models and compare it with the data that we have to make sure we're getting correct answers and make sure our climate models are reflecting the best information."

  15. Composition and Characteristics of Aerosols in the Southern High Plains of Texas (USA)

    SciTech Connect (OSTI)

    Gill, Thomas E. [Department of Geological Sciences, University of Texas at El Paso, 500 West University Avenue, El Paso TX 79968 (United States); Environmental Science and Engineering Program, University of Texas at El Paso, 500 West University Avenue, El Paso TX 79968 (United States); Stout, John E. [Wind Erosion and Water Conservation Research Unit, Agricultural Research Service, US Department of Agriculture, 3810 Fourth Street, Lubbock TX 79415 (United States); Peinado, Porfirio [Environmental Science and Engineering Program, University of Texas at El Paso, 500 West University Avenue, El Paso TX 79968 (United States)

    2009-03-10T23:59:59.000Z

    Aerosol samples on polycarbonate filters were collected daily for several years in the Southern High Plains region of western Texas. Selected samples representing a variety of size modes, locations, and air quality conditions were analyzed by PIXE. Silicon and other crustal elements dominated during dust storms and in the coarse mode; sulfur dominated during anthropogenic pollution episodes and in the fine mode. A mixture of both aerosol types was present even during 'clear' conditions. The Al/Si ratio in dust events increases with wind speed. These data provide an initial assessment of aerosol chemistry in the West Texas plains.

  16. Dynamic Processes in Biology, Chemistry, and Materials Science: Opportunities for UltraFast Transmission Electron Microscopy - Workshop Summary Report

    SciTech Connect (OSTI)

    Kabius, Bernd C.; Browning, Nigel D.; Thevuthasan, Suntharampillai; Diehl, Barbara L.; Stach, Eric A.

    2012-07-25T23:59:59.000Z

    This report summarizes a 2011 workshop that addressed the potential role of rapid, time-resolved electron microscopy measurements in accelerating the solution of important scientific and technical problems. A series of U.S. Department of Energy (DOE) and National Academy of Science workshops have highlighted the critical role advanced research tools play in addressing scientific challenges relevant to biology, sustainable energy, and technologies that will fuel economic development without degrading our environment. Among the specific capability needs for advancing science and technology are tools that extract more detailed information in realistic environments (in situ or operando) at extreme conditions (pressure and temperature) and as a function of time (dynamic and time-dependent). One of the DOE workshops, Future Science Needs and Opportunities for Electron Scattering: Next Generation Instrumentation and Beyond, specifically addressed the importance of electron-based characterization methods for a wide range of energy-relevant Grand Scientific Challenges. Boosted by the electron optical advancement in the last decade, a diversity of in situ capabilities already is available in many laboratories. The obvious remaining major capability gap in electron microscopy is in the ability to make these direct in situ observations over a broad spectrum of fast (µs) to ultrafast (picosecond [ps] and faster) temporal regimes. In an effort to address current capability gaps, EMSL, the Environmental Molecular Sciences Laboratory, organized an Ultrafast Electron Microscopy Workshop, held June 14-15, 2011, with the primary goal to identify the scientific needs that could be met by creating a facility capable of a strongly improved time resolution with integrated in situ capabilities. The workshop brought together more than 40 leading scientists involved in applying and/or advancing electron microscopy to address important scientific problems of relevance to DOE’s research mission. This workshop built on previous workshops and included three breakout sessions identifying scientific challenges in biology, biogeochemistry, catalysis, and materials science frontier areas of fundamental science that underpin energy and environmental science that would significantly benefit from ultrafast transmission electron microscopy (UTEM). In addition, the current status of time-resolved electron microscopy was examined, and the technologies that will enable future advances in spatio-temporal resolution were identified in a fourth breakout session.

  17. Chemistry 106X -Fall 2010 General Chemistry

    E-Print Network [OSTI]

    Wagner, Diane

    Chemistry 106X - Fall 2010 General Chemistry Instructor: Christopher Iceman Class: MWF 9 bookstore or elsewhere: · Chemistry and Chemical Reactivity 7th Ed. by Kotz, Treichel, and Townsend-0-495-38703-9 Electronic Book - ISBN 978-0-495-68043-7 · OWL pin number for Chemistry and Chemical Reactivity 7th Ed. (1

  18. Chemistry 411/611 Inorganic Chemistry (2011)

    E-Print Network [OSTI]

    Mather, Patrick T.

    2011-01-01T23:59:59.000Z

    1 Chemistry 411/611 Inorganic Chemistry (2011) Instructor: Assistant Professor Mathew M. Maye Chemistry", 5th Edition, Freeman Press. Available at SU bookstore. The solution manual is optional. (Suggested for CHE611 Students pursuing Inorganic) Huheey, "Inorganic Chemistry: Principles of Structure

  19. Chemistry 106X -Spring 2011 General Chemistry

    E-Print Network [OSTI]

    Wagner, Diane

    Chemistry 106X - Spring 2011 General Chemistry Instructor: Christopher Iceman Class: MWF 1 and can be purchased in the UAF bookstore or elsewhere: · Chemistry and Chemical Reactivity 7th Ed for Chemistry and Chemical Reactivity 7th Ed. (1 or 2 semester) · TurningPoint Technologies ResponseCard RF

  20. Climate implications of carbonaceous aerosols: An aerosol microphysical study using the GISS/MATRIX climate model

    E-Print Network [OSTI]

    Bauer, Susanne E.

    2010-01-01T23:59:59.000Z

    and R. Ruedy, Matrix (multiconfiguration aerosol tracker ofmixing state): An aerosol microphysical module for globalAn investigative review, Aerosol Sci. Technol. , Vol. 40,

  1. A New Aerosol Flow System for Photochemical and Thermal Studies...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Aerosol Flow System for Photochemical and Thermal Studies of Tropospheric Aerosols. A New Aerosol Flow System for Photochemical and Thermal Studies of Tropospheric Aerosols....

  2. School of Chemistry CHEM3100: Chemistry at a Molecular Level

    E-Print Network [OSTI]

    Rzepa, Henry S.

    School of Chemistry CHEM3100: Chemistry at a Molecular Level Tutorial Groups 2013/14 Name Programme Tutor Ahmed, Zacher Medicinal Chemistry Arif, Saboor Chemistry Bagnall, Samuel Chemistry Barbara, David Chemistry Beaumont, Nicholas Chemistry Quinn, Michael J Chemistry Bennett, Matthew Chemistry Booth, Natalie

  3. 6, 11791198, 2006 Aerosols closing

    E-Print Network [OSTI]

    Boyer, Edmond

    ACPD 6, 1179­1198, 2006 Aerosols closing open Benard cells D. Rosenfeld et al. Title Page Abstract of precipitation by aerosols D. Rosenfeld1 , Y. J. Kaufman2 , and I. Koren3 1 Institute of Earth Sciences­1198, 2006 Aerosols closing open Benard cells D. Rosenfeld et al. Title Page Abstract Introduction

  4. 8, 14571503, 2008 The aerosol

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ACPD 8, 1457­1503, 2008 The aerosol distribution in Europe V. Matthias Title Page Abstract Discussions The aerosol distribution in Europe derived with the Community Multiscale Air Quality (CMAQ) model.matthias@gkss.de) 1457 #12;ACPD 8, 1457­1503, 2008 The aerosol distribution in Europe V. Matthias Title Page Abstract

  5. CHEMISTRY CURRICULUM SEMESTER I

    E-Print Network [OSTI]

    Srinivasan, N.

    CHEMISTRY CURRICULUM SEMESTER ­ I Chemistry-I: Physical principles (2:1) Atomic structure-state approximation, Arrhenius equation and collision theory and catalysis. SEMESTER ­ II Chemistry-II: Structure orbital theory: polyatomic molecules - Walsh diagram; Main group chemistry: periodic properties, chemistry

  6. Highly stable aerosol generator

    DOE Patents [OSTI]

    DeFord, H.S.; Clark, M.L.

    1981-11-03T23:59:59.000Z

    An improved compressed air nebulizer has been developed such that a uniform aerosol particle size and concentration may be produced over long time periods. This result is achieved by applying a vacuum pressure to the makeup assembly and by use of a vent tube between the atmosphere and the makeup solution. By applying appropriate vacuum pressures to the makeup solution container and by proper positioning of the vent tube, a constant level of aspirating solution may be maintained within the aspirating assembly with aspirating solution continuously replaced from the makeup solution supply. This device may also be adapted to have a plurality of aerosol generators and only one central makeup assembly. 2 figs.

  7. Aerosol collection characteristics of ambient aerosol samplers 

    E-Print Network [OSTI]

    Ortiz, Carlos A

    1978-01-01T23:59:59.000Z

    . These samplers have an effic1ency approach1ng 100 percent for particles for which the gravitational and 1nertial forces are small (less than approximately 5 um); however, for larger-sized part1cles the efficiency is quite variable and depends not only upon.... According to Agarwal, representative samples can be collected by an aerosol instrument without meeting the Davies criter1a. Raynor ( 7), with the aid of a wind tunnel, observed the effects of environmental and physical parameters on the entrance effic1...

  8. Geometrical Optics of Dense Aerosols

    SciTech Connect (OSTI)

    Hay, Michael J.; Valeo, Ernest J.; Fisch, Nathaniel J.

    2013-04-24T23:59:59.000Z

    Assembling a free-standing, sharp-edged slab of homogeneous material that is much denser than gas, but much more rare ed than a solid, is an outstanding technological challenge. The solution may lie in focusing a dense aerosol to assume this geometry. However, whereas the geometrical optics of dilute aerosols is a well-developed fi eld, the dense aerosol limit is mostly unexplored. Yet controlling the geometrical optics of dense aerosols is necessary in preparing such a material slab. Focusing dense aerosols is shown here to be possible, but the nite particle density reduces the eff ective Stokes number of the flow, a critical result for controlled focusing. __________________________________________________

  9. Chemistry Division: Annual progress report for period ending March 31, 1987

    SciTech Connect (OSTI)

    Not Available

    1987-08-01T23:59:59.000Z

    This report is divided into the following sections: coal chemistry; aqueous chemistry at high temperatures and pressures; geochemistry of crustal processes to high temperatures and pressures; chemistry of advanced inorganic materials; structure and dynamics of advanced polymeric materials; chemistry of transuranium elements and compounds; separations chemistry; reactions and catalysis in molten salts; surface science related to heterogeneous catalysis; electron spectroscopy; chemistry related to nuclear waste disposal; computational modeling of security document printing; and special topics. (DLC)

  10. Absorbing Aerosol Index (AAI) The residue method for the detection of aerosols

    E-Print Network [OSTI]

    Graaf, Martin de

    Absorbing Aerosol Index (AAI) The residue method for the detection of aerosols from space reflection and absorption Surface Rayleigh atmosphere #12;TOA Multiple scattering Multiple scattering Aerosol layer satellite Surface reflection and absorption Surface Rayleigh atmosphere Rayleigh atmophere Aerosol

  11. Electrostatics and radioactive aerosol behavior

    SciTech Connect (OSTI)

    Clement, C.F.

    1994-12-31T23:59:59.000Z

    Radioactive aerosols differ from their nonradioactive counterparts by their ability to charge themselves by emitting charged particles during the radioactive decay process. Evidence that electrostatics, including this charging process, can affect the transport of the aerosols was summarized previously. Charge distributions and the mean charge for a monodisperse radioactive aerosol have been considered in detail. The principal results of theory to calculate charge distributions on a aerosol with a size distribution, changes to Brownian coagulation rates for an aerosol in a reactor containment, and possible changes to aerosol deposition resulting from the charging will be presented. The main purpose of the work has been to improve calculations of aerosol behavior in reactor containments, but behavior in less ionizing environments will be affected more strongly, and some problems remain to be solved in performing reliable calculations.

  12. aerosols and climate : uncertainties

    E-Print Network [OSTI]

    contributes to creating a level playing field. (BC emissions tradeble like CO2 emissions?) OUTLINE #12;size. policy measures, is even more uncertain (emissions & their chemical fingerprint are uncertain (not just aerosol emissions, not just climate impacts) OUTLINE #12;- Standardization doesn't reduce

  13. MASS SPECTROMETRIC APPROACHES FOR CHEMICAL CHARACTERISATION OF ATMOSPHERIC AEROSOLS: CRITICAL REVIEW OF MOST RECENT ADVANCES

    SciTech Connect (OSTI)

    Laskin, Alexander; Laskin, Julia; Nizkorodov, Sergey

    2012-06-29T23:59:59.000Z

    This manuscript presents an overview of the most recent instrument developments, field and laboratory applications of mass spectrometry (MS) in chemistry and physics of atmospheric aerosols. A broad range of MS instruments employing different sample introduction methods, ionization and mass detection techniques are utilized for both “on?line” and “off?line” characterization of aerosols. On?line MS techniques enable detection of individual particles with simultaneous measurements of particle size distributions and aerodynamic characteristics, and are ideally suited for field studies which require high temporal resolution. Off?line MS techniques provide means for detailed molecular?level analysis of aerosol samples which is essential to fundamental knowledge on aerosol chemistry, mechanisms of particle formation and atmospheric aging. Combined together, complementary MS techniques provide comprehensive information on the chemical composition, size, morphology and phase of aerosols ? data of key importance for evaluating hygroscopic and optical properties of particles, their health effects, understanding their origins, and atmospheric evolution. Developments and applications of MS techniques in the aerosol research have expanded remarkably over a couple of last years as evidenced by sky?rocketing publication statistics. The goal of this review is to period of late 2010 ? early2012, which were not conveyed in previous reviews.

  14. Green Chemistry and Workers

    E-Print Network [OSTI]

    2009-01-01T23:59:59.000Z

    19. P. Anastas, J. Warner. 1998. Green Chemistry: Theory andto Advance New Science, Green Chemistry and EnvironmentalChronicle Extra: Guide to Green Jobs. Field with a Future.

  15. 6, 43414373, 2006 Cloud-borne aerosol

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Discussions Impact of cloud-borne aerosol representation on aerosol direct and indirect effects S. J. Ghan of aerosols employ a variety of rep- resentations of such cloud-borne particles. Here we use a global aerosol- ulated aerosol, cloud and radiation fields to various approximations to the representa- tion of cloud

  16. Radiative forcing due to major aerosol emitting sectors in China and India

    E-Print Network [OSTI]

    emissions in key sectors of China and India using the GISS-E2 chemistry-climate model. Diesel trucks aerosol sources is essential for making effective emission control decisions to mitigate climate change, annual average forcings due mainly to the direct and indirect effects of BC. Emissions from these two

  17. Supplement for "Secondary organic aerosol1 formation from idling gasoline passenger vehicle2

    E-Print Network [OSTI]

    Meskhidze, Nicholas

    Supplement for "Secondary organic aerosol1 formation from idling gasoline passenger vehicle2.O. Box 503, FIN-00101 Helsinki, Finland}14 [5]{Department of Chemistry, Atmospheric Science, University experiment show a total concentration of light aromatics of less than 1 ppb.6 Vehicles7 In total six gasoline

  18. Chemistry 411/611 Inorganic Chemistry (2010)

    E-Print Network [OSTI]

    Mather, Patrick T.

    2010-01-01T23:59:59.000Z

    -ligand reactivity, and the chemical synthesis of coordination compounds and other "solid" state materials 1 Chemistry 411/611 Inorganic Chemistry (2010) Instructor: Assistant Professor Mathew M. Maye: M-W 4:00-5:00, and by appointment Credits: 3 Text: (Required) Shriver & Atkins, "Inorganic Chemistry

  19. FACULTY POSITION IN INORGANIC CHEMISTRY Department of Chemistry

    E-Print Network [OSTI]

    Doyle, Robert

    FACULTY POSITION IN INORGANIC CHEMISTRY Department of Chemistry Syracuse University The Department of Chemistry at Syracuse University invites applications for a tenure track faculty position at the Assistant Professor level in inorganic chemistry with specialization in materials chemistry (broadly defined

  20. Representing Cloud Processing of Aerosol in Numerical Models

    SciTech Connect (OSTI)

    Mechem, D.B.; Kogan, Y.L.

    2005-03-18T23:59:59.000Z

    The satellite imagery in Figure 1 provides dramatic examples of how aerosol influences the cloud field. Aerosol from ship exhaust can serve as nucleation centers in otherwise cloud-free regions, forming ship tracks (top image), or can enhance the reflectance/albedo in already cloudy regions. This image is a demonstration of the first indirect effect, in which changes in aerosol modulate cloud droplet radius and concentration, which influences albedo. It is thought that, through the effects it has on precipitation (drizzle), aerosol can also affect the structure and persistence of planetary boundary layer (PBL) clouds. Regions of cellular convection, or open pockets of cloudiness (bottom image) are thought to be remnants of strongly drizzling PBL clouds. Pockets of Open Cloudiness (POCs) (Stevens et al. 2005) or Albrecht's ''rifts'' are low cloud fraction regions characterized by anomalously low aerosol concentrations, implying they result from precipitation. These features may in fact be a demonstration of the second indirect effect. To accurately represent these clouds in numerical models, we have to treat the coupled cloud-aerosol system. We present the following series of mesoscale and large eddy simulation (LES) experiments to evaluate the important aspects of treating the coupled cloud-aerosol problem. 1. Drizzling and nondrizzling simulations demonstrate the effect of drizzle on a mesoscale forecast off the California coast. 2. LES experiments with explicit (bin) microphysics gauge the relative importance of the shape of the aerosol spectrum on the 3D dynamics and cloud structure. 3. Idealized mesoscale model simulations evaluate the relative roles of various processes, sources, and sinks.

  1. Integrating chemistry into 3D climate models: Detailed kinetics in the troposphere and stratosphere of a global climate model

    SciTech Connect (OSTI)

    Kao, C.Y.J.; Elliott, S. [Los Alamos National Lab., NM (United States). Earth and Environmental Sciences Div.; Turco, R.P.; Zhao, X. [Univ. of California, Los Angeles, CA (United States)

    1997-11-01T23:59:59.000Z

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The motivation for the project is to create the first complete, three-dimensional climate model that enfolds atmospheric photochemistry. The LANL chemical global climate model (GCM) not only distributes the trace greenhouse gases and modifies their concentrations within the detailed photochemical web, but also permits them to influence the radiation field and so force their own transport. Both atmospheric chemistry and fluid dynamics are nonlinear and zonally asymmetric phenomena. They can only be adequately modeled in three dimensions on the global grid. The kinetics-augmented GCM is the only program within the atmospheric community capable of investigating interaction involving chemistry and transport. The authors have conducted case studies of timely three-dimensional chemistry issues. Examples include ozone production from biomass burning plumes, kinetic feedbacks in zonally asymmetric transport phenomena with month- to year-long time scales, and volcano sulfate aerosols with respect to their potential effects on tropospheric ozone depletion.

  2. ARM: 10-minute TEMPORARY Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sivaraman, Chitra; Flynn, Connor

    10-minute TEMPORARY Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  3. Aerosol Retrieval Using Remote-sensed Observations

    E-Print Network [OSTI]

    Wang, Yueqing

    2012-01-01T23:59:59.000Z

    1.2 Aerosols Impacts on HumanBayesian Approach for Aerosol Retrieval Using MISR Data 2.1for Including a Richer Variety of Aerosol Compositions . 2.5

  4. Optical Properties of Secondary Organic Aerosols

    E-Print Network [OSTI]

    Kim, Hwajin

    2012-01-01T23:59:59.000Z

    Paulson, S. E. ; Chung, A. Aerosol Sci. Technol. 2007 , 41,Y. G. ; Daum, P. H. J. Aerosol Sci 2008 , 39, 974-986. (32)Accurate Monitoring of Terrestrial Aerosols and Total Solar

  5. Aerosol Observing System (AOS) Handbook

    SciTech Connect (OSTI)

    Jefferson, A

    2011-01-17T23:59:59.000Z

    The Aerosol Observing System (AOS) is a suite of in situ surface measurements of aerosol optical and cloud-forming properties. The instruments measure aerosol properties that influence the earth’s radiative balance. The primary optical measurements are those of the aerosol scattering and absorption coefficients as a function of particle size and radiation wavelength and cloud condensation nuclei (CCN) measurements as a function of percent supersaturation. Additional measurements include those of the particle number concentration and scattering hygroscopic growth. Aerosol optical measurements are useful for calculating parameters used in radiative forcing calculations such as the aerosol single-scattering albedo, asymmetry parameter, mass scattering efficiency, and hygroscopic growth. CCN measurements are important in cloud microphysical models to predict droplet formation.

  6. Nonequilibrium Atmospheric Secondary Organic Aerosol Formation...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Aerosol Formation and Growth. Abstract: Airborne particles play a critical role in air quality, human health effects, visibility and climate. Secondary organic aerosols (SOA)...

  7. Sunlight Changes Aerosols in Clouds | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Sunlight Changes Aerosols in Clouds Sunlight Changes Aerosols in Clouds Released: October 20, 2011 Scientists show how sunlight alters optical, chemical properties of atmospheric...

  8. Molecular Characterization of Biomass Burning Aerosols Using...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomass Burning Aerosols Using High Resolution Mass Spectrometry. Molecular Characterization of Biomass Burning Aerosols Using High Resolution Mass Spectrometry. Abstract: Chemical...

  9. Clustering of Aerosols in Atmospheric Turbulent Flow

    E-Print Network [OSTI]

    T. Elperin; N. Kleeorin; M. A. Liberman; V. L'vov; I. Rogachevskii

    2007-02-15T23:59:59.000Z

    A mechanism of formation of small-scale inhomogeneities in spatial distributions of aerosols and droplets associated with clustering instability in the atmospheric turbulent flow is discussed. The particle clustering is a consequence of a spontaneous breakdown of their homogeneous space distribution due to the clustering instability, and is caused by a combined effect of the particle inertia and a finite correlation time of the turbulent velocity field. In this paper a theoretical approach proposed in Phys. Rev. E 66, 036302 (2002) is further developed and applied to investigate the mechanisms of formation of small-scale aerosol inhomogeneities in the atmospheric turbulent flow. The theory of the particle clustering instability is extended to the case when the particle Stokes time is larger than the Kolmogorov time scale, but is much smaller than the correlation time at the integral scale of turbulence. We determined the criterion of the clustering instability for the Stokes number larger than 1. We discussed applications of the analyzed effects to the dynamics of aerosols and droplets in the atmospheric turbulent flow.

  10. Why chemistry? Chemistry is fundamental: it is the enabling

    E-Print Network [OSTI]

    Sussex, University of

    Chemistry Why chemistry? Chemistry is fundamental: it is the enabling science that underlies many technology. A chemistry degree gives you the understanding to contribute to our future in very topical areas) in Chemistry BSc (Hons) in Chemistry MChem (Hons) in Chemistry (with an industrial placement year) MChem (Hons

  11. Signatures of fractal clustering of aerosols advected under gravity

    E-Print Network [OSTI]

    Rafael Dias Vilela; Tamás Tél; Alessandro P. S. de Moura; Celso Grebogi

    2007-06-15T23:59:59.000Z

    Aerosols under chaotic advection often approach a strange attractor. They move chaotically on this fractal set but, in the presence of gravity, they have a net vertical motion downwards. In practical situations, observational data may be available only at a given level, for example at the ground level. We uncover two fractal signatures of chaotic advection of aerosols under the action of gravity. Each one enables the computation of the fractal dimension $D_{0}$ of the strange attractor governing the advection dynamics from data obtained solely at a given level. We illustrate our theoretical findings with a numerical experiment and discuss their possible relevance to meteorology.

  12. 7, 37193761, 2007 Aerosol indirect

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    effects and is defined as the difference in the top-of-the-atmosphere net radiation be- tween present when either a statistical cloud cover scheme or a different aerosol emission inventory are employed. 1ACPD 7, 3719­3761, 2007 Aerosol indirect effects in ECHAM5-HAM U. Lohmann et al. Title Page

  13. 4, 75617614, 2004 Indirect aerosol

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    . While the cloud albedo enhance- ment (Twomey effect) of warm clouds received most attention so far, they can15 scatter, absorb and emit thermal radiation. Thirdly aerosol particles act as cloud con properties influenced by20 aerosols (e.g. semi-direct effect, suppression of convection). Clouds themselves

  14. 7, 1268712714, 2007 Aerosols' influence

    E-Print Network [OSTI]

    Boyer, Edmond

    in the polluted cloud is due to a more efficient collection process. 1 Introduction10 The effect of aerosol). Numerous studies have addressed the effect of aerosol on marine stratocumulus clouds, due to their key role in the global radiative energy. Marine stratocumuli, bounded by strong marine boundary layer inversion, have

  15. Ganges Valley Aerosol Experiment: Science and Operations Plan

    SciTech Connect (OSTI)

    Kotamarthi, VR

    2010-06-21T23:59:59.000Z

    The Ganges Valley region is one of the largest and most rapidly developing sections of the Indian subcontinent. The Ganges River, which provides the region with water needed for sustaining life, is fed primarily by snow and rainfall associated with Indian summer monsoons. Impacts of changes in precipitation patterns, temperature, and the flow of the snow-fed rivers can be immense. Recent satellite-based measurements have indicated that the upper Ganges Valley has some of the highest persistently observed aerosol optical depth values. The aerosol layer covers a vast region, extending across the Indo-Gangetic Plain to the Bay of Bengal during the winter and early spring of each year. The persistent winter fog in the region is already a cause of much concern, and several studies have been proposed to understand the economic, scientific, and societal dimensions of this problem. During the INDian Ocean EXperiment (INDOEX) field studies, aerosols from this region were shown to affect cloud formation and monsoon activity over the Indian Ocean. This is one of the few regions showing a trend toward increasing surface dimming and enhanced mid-tropospheric warming. Increasing air pollution over this region could modify the radiative balance through direct, indirect, and semi-indirect effects associated with aerosols. The consequences of aerosols and associated pollution for surface insolation over the Ganges Valley and monsoons, in particular, are not well understood. The proposed field study is designed for use of (1) the ARM Mobile Facility (AMF) to measure relevant radiative, cloud, convection, and aerosol optical characteristics over mainland India during an extended period of 9–12 months and (2) the G-1 aircraft and surface sites to measure relevant aerosol chemical, physical, and optical characteristics in the Ganges Valley during a period of 6–12 weeks. The aerosols in this region have complex sources, including burning of coal, biomass, and biofuels; automobile emissions; and dust. The extended AMF deployment will enable measurements under different regimes of the climate and aerosol abundance—in the wet monsoon period with low aerosol loading; in the dry, hot summer with aerosols dispersed throughout the atmospheric column; and in the cool, dry winter with aerosols confined mostly to the boundary later and mid-troposphere. Each regime, in addition, has its own distinct radiative and atmospheric dynamic drivers. The aircraft operational phase will assist in characterizing the aerosols at times when they have been observed to be at the highest concentrations. A number of agencies in India will collaborate with the proposed field study and provide support in terms of planning, aircraft measurements, and surface sites. The high concentration of aerosols in the upper Ganges Valley, together with hypotheses involving several possible mechanisms with direct impacts on the hydrologic cycle of the region, gives us a unique opportunity to generate data sets that will be useful both in understanding the processes at work and in providing answers regarding the effects of aerosols on climate in a region where the perturbation is the highest.

  16. Aerosol Imaging with a Soft X-ray Free Electron Laser

    SciTech Connect (OSTI)

    Bogan, Michael J.; /SLAC /LLNL, Livermore; Boutet, Sebastien; /SLAC; Chapman, Henry N.; /DESY /Hamburg U.; Marchesini, Stefano; /LBL, Berkeley; Barty, Anton; Benner, W.Henry /LLNL, Livermore; Rohner, Urs; /LLNL, Livermore /TOFWERK AG; Frank, Matthias; Hau-Riege, Stefan P.; /LLNL, Livermore; Bajt, Sasa; /DESY; Woods, Bruce; /LLNL, Livermore; Seibert, M.M.; Iwan, Bianca; Timneanu, Nicusor; Hajdu, Janos; /Uppsala U.; Schulz, Joachim; /DESY

    2011-08-22T23:59:59.000Z

    Lasers have long played a critical role in the advancement of aerosol science. A new regime of ultrafast laser technology has recently be realized, the world's first soft xray free electron laser. The Free electron LASer in Hamburg, FLASH, user facility produces a steady source of 10 femtosecond pulses of 7-32 nm x-rays with 10{sub 12} photons per pulse. The high brightness, short wavelength, and high repetition rate (>500 pulses per second) of this laser offers unique capabilities for aerosol characterization. Here we use FLASH to perform the highest resolution imaging of single PM2.5 aerosol particles in flight to date. We resolve to 35 nm the morphology of fibrous and aggregated spherical carbonaceous nanoparticles that existed for less than two milliseconds in vacuum. Our result opens the possibility for high spatialand time-resolved single particle aerosol dynamics studies, filling a critical technological need in aerosol science.

  17. Lognormal Size Distribution Theory for Deposition of Polydisperse Aerosol Particles

    SciTech Connect (OSTI)

    Park, S.H.; Lee, K.W. [Kwangju Institute of Science and Technology (Korea, Republic of)

    2000-07-15T23:59:59.000Z

    The moments method of the lognormal size distribution theory was applied to the deposition equation of a radioactive aerosol within a liquid-metal fast breeder reactor for analysis of postulated accidents. The deposition coefficient of Crump and Seinfeld was utilized to represent the Brownian and turbulent diffusions and the gravitational sedimentation. The deposition equation was converted into a set of three ordinary differential equations. This approach takes the view point that the size distribution of an aerosol is represented by a time-dependent lognormal size distribution function during the deposition process. Numerical calculations have been performed, and the results were found to be in good agreement with the exact solution. The derived model for aerosol deposition is convenient to use in a numerical general dynamic equation solution routine based on the moments method, where nucleation, condensation, coagulation, and deposition need to be solved simultaneously.

  18. Aerosol Science and Technology, 42:115, 2008 Copyright c American Association for Aerosol Research

    E-Print Network [OSTI]

    Aerosol Science and Technology, 42:1­15, 2008 Copyright c American Association for Aerosol Research of a Fast-Response Aerosol Size Spectrometer Jason S. Olfert and Jian Wang Atmospheric Science Department by the mixing of the aerosol in the inlet of the instrument, which `smears' the detected aerosol over a range

  19. Climatological simulations of ozone and atmospheric aerosols in the Greater Cairo region

    SciTech Connect (OSTI)

    Steiner, A. L.; Tawfik, A. B.; Shalaby, A.; Zakey, A. S.; Abdel Wahab, M. M.; Salah, Z.; Solmon, F.; Sillman, S.; Zaveri, Rahul A.

    2014-04-16T23:59:59.000Z

    An integrated chemistry-climate model (RegCM4-CHEM) simulates present-day climate, ozone and tropospheric aerosols over Egypt with a focus on Greater Cairo (GC) region. The densley populated GC region is known for its severe air quality issues driven by high levels of anthropogenic pollution in conjuction with natural sources such as dust and agricultural burning events. We find that current global emission inventories underestimate key pollutants such as nitrogen oxides and anthropogenic aerosol species. In the GC region, average-ground-based NO2 observations of 40-60 ppb are substantially higher than modeled estimates (5-10 ppb), likely due to model grid resolution, improper boundary layer representation, and poor emissions inventories. Observed ozone concentrations range from 35 ppb (winter) to 80 ppb (summer). The model reproduces the seasonal cycle fairly well, but modeled summer ozone is understimated by approximately 15 ppb and exhibits little interannual variability. For aerosols, springtime dust events dominate the seasonal aerosol cycle. The chemistry-climate model captures the springtime peak aerosol optical depth (AOD) of 0.7-1 but is slightly greater than satellite-derived AOD. Observed AOD decreases in the summer and increases again in the fall due to agricultural burning events in the Nile Delta, yet the model underestimates this fall observed AOD peak, as standard emissions inventories underestimate this burning and the resulting aerosol emissions. Our comparison of modeled gas and particulate phase atmospheric chemistry in the GC region indicates that improved emissions inventories of mobile sources and other anthropogenic activities are needed to improve air quality simulations in this region.

  20. The Nearby Supernova Factory Ozone + Aerosol + Rayleigh

    E-Print Network [OSTI]

    Rayleigh + Aerosol Extinction monitor filter Auxiliary Camera CCD Spectrograph picko ff mirror Umbra

  1. MELCOR 1.8.2 assessment: Aerosol experiments ABCOVE AB5, AB6, AB7, and LACE LA2

    SciTech Connect (OSTI)

    Souto, F.J.; Haskin, F.E. [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Chemical and Nuclear Engineering; Kmetyk, L.N. [Sandia National Labs., Albuquerque, NM (United States)

    1994-10-01T23:59:59.000Z

    The MELCOR computer code has been used to model four of the large-scale aerosol behavior experiments conducted in the Containment System Test Facility (CSTF) vessel. Tests AB5, AB6 and AB7 of the ABCOVE program simulate the dry aerosol conditions during a hypothetical severe accident in an LMFBR. Test LA2 of the LACE program simulates aerosol behavior in a condensing steam environment during a postulated severe accident in an LWR with failure to isolate the containment. The comparison of code results to experimental data show that MELCOR is able to correctly predict most of the thermal-hydraulic results in the four tests. MELCOR predicts reasonably well the dry aerosol behavior of the ABCOVE tests, but significant disagreements are found in the aerosol behavior modelling for the LA2 experiment. These results tend to support some of the concerns about the MELCOR modelling of steam condensation onto aerosols expressed in previous works. During these analyses, a limitation in the MELCOR input was detected for the specification of the aerosol parameters for more than one component. A Latin Hypercube Sampling (LHS) sensitivity study of the aerosol dynamic constants is presented for test AB6. The study shows the importance of the aerosol shape factors in the aerosol deposition behavior, and reveals that MELCOR input/output processing is highly labor intensive for uncertainty and sensitivity analyses based on LHS.

  2. Observations of the first aerosol indirect effect in shallow cumuli

    SciTech Connect (OSTI)

    Berg, Larry K.; Berkowitz, Carl M.; Barnard, James C.; Senum, Gunar; Springston, Stephen R.

    2011-02-08T23:59:59.000Z

    Data from the Cumulus Humilis Aerosol Processing Study (CHAPS) are used to estimate the impact of both aerosol indirect effects and cloud dynamics on the microphysical and optical properties of shallow cumuli observed in the vicinity of Oklahoma City, Oklahoma. Not surprisingly, we find that the amount of light scattered by the clouds is dominated by their liquid water content (LWC), which in turn is driven by cloud dynamics. However, removing the effect of cloud dynamics by examining the scattering normalized by LWC shows a strong sensitivity of scattering to pollutant loading. These results suggest that even moderately sized cities, like Oklahoma City, can have a measureable impact on the optical properties of shallow cumuli.

  3. Computational Chemistry Robots

    E-Print Network [OSTI]

    Townsend, Joseph A; Murray-Rust, Peter; Tyrrell, Simon M; Zhang, Yong

    Computational Chemistry Robots ACS Sep 2005 Computational Chemistry Robots J. A. Townsend, P. Murray-Rust, S. M. Tyrrell, Y. Zhang jat45@cam.ac.uk Can high-throughput computation provide a reliable “experimental” resource for molecular...

  4. Soft ionization of thermally evaporated hypergolic ionic liquid aerosols

    E-Print Network [OSTI]

    Koh, Christine J.

    2013-01-01T23:59:59.000Z

    + ][Dca ? ]. Figure 2. Aerosol particle size distribution ofhypergolic ionic liquid aerosols Christine J. Koh † , Chen-ionization of evaporated IL aerosols Isolated ion pairs of a

  5. Amine-Amine Exchange in Aminium-Methanesulfonate Aerosols. |...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Amine-Amine Exchange in Aminium-Methanesulfonate Aerosols. Amine-Amine Exchange in Aminium-Methanesulfonate Aerosols. Abstract: Aerosol particles are ubiquitous in the atmosphere...

  6. Effect of Hydrophobic Primary Organic Aerosols on Secondary Organic...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hydrophobic Primary Organic Aerosols on Secondary Organic Aerosol Formation from Ozonolysis of ?-Pinene. Effect of Hydrophobic Primary Organic Aerosols on Secondary Organic...

  7. Mexico City Aerosol Analysis during MILAGRO using High Resolution...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2: Mexico City Aerosol Analysis during MILAGRO using High Resolution Aerosol Mass Spectrometry at the Urban Supersite (T0). Part 2: Abstract: Submicron aerosol was analyzed during...

  8. Mexico City Aerosol Analysis during MILAGRO using High Resolution...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1: Mexico City Aerosol Analysis during MILAGRO using High Resolution Aerosol Mass Spectrometry at the Urban Supersite (T0). Part 1: Abstract: Submicron aerosol was analyzed during...

  9. aerosol particles collected: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Saller 2002-05-07 6 Nanomaterials from Aerosols Aerosols are suspensions of liquid or solid particles in a gas. Aerosol particles Materials Science Websites Summary: being clouds...

  10. Parameterizations of Cloud Microphysics and Indirect Aerosol Effects

    SciTech Connect (OSTI)

    Tao, Wei-Kuo [NASA/GSFC] [NASA/GSFC

    2014-05-19T23:59:59.000Z

    1. OVERVIEW Aerosols and especially their effect on clouds are one of the key components of the climate system and the hydrological cycle [Ramanathan et al., 2001]. Yet, the aerosol effect on clouds remains largely unknown and the processes involved not well understood. A recent report published by the National Academy of Science states "The greatest uncertainty about the aerosol climate forcing - indeed, the largest of all the uncertainties about global climate forcing - is probably the indirect effect of aerosols on clouds [NRC, 2001]." The aerosol effect on clouds is often categorized into the traditional "first indirect (i.e., Twomey)" effect on the cloud droplet sizes for a constant liquid water path [Twomey, 1977] and the "semi-direct" effect on cloud coverage [e.g., Ackerman et al., 2000]. Enhanced aerosol concentrations can also suppress warm rain processes by producing a narrow droplet spectrum that inhibits collision and coalescence processes [e.g., Squires and Twomey, 1961; Warner and Twomey, 1967; Warner, 1968; Rosenfeld, 1999]. The aerosol effect on precipitation processes, also known as the second type of aerosol indirect effect [Albrecht, 1989], is even more complex, especially for mixed-phase convective clouds. Table 1 summarizes the key observational studies identifying the microphysical properties, cloud characteristics, thermodynamics and dynamics associated with cloud systems from high-aerosol continental environments. For example, atmospheric aerosol concentrations can influence cloud droplet size distributions, warm-rain process, cold-rain process, cloud-top height, the depth of the mixed phase region, and occurrence of lightning. In addition, high aerosol concentrations in urban environments could affect precipitation variability by providing an enhanced source of cloud condensation nuclei (CCN). Hypotheses have been developed to explain the effect of urban regions on convection and precipitation [van den Heever and Cotton, 2007 and Shepherd, 2005]. Recently, a detailed spectral-bin microphysical scheme was implemented into the Goddard Cumulus Ensemble (GCE) model. Atmospheric aerosols are also described using number density size-distribution functions. A spectral-bin microphysical model is very expensive from a computational point of view and has only been implemented into the 2D version of the GCE at the present time. The model is tested by studying the evolution of deep tropical clouds in the west Pacific warm pool region and summertime convection over a mid-latitude continent with different concentrations of CCN: a low "clean" concentration and a high "dirty" concentration. The impact of atmospheric aerosol concentration on cloud and precipitation will be investigated. 2. MODEL DESCRIPTION AND CASE STUDIES 2.1 GCE MODEL The model used in this study is the 2D version of the GCE model. Modeled flow is anelastic. Second- or higher-order advection schemes can produce negative values in the solution. Thus, a Multi-dimensional Positive Definite Advection Transport Algorithm (MPDATA) has been implemented into the model. All scalar variables (potential temperature, water vapor, turbulent coefficient and all five hydrometeor classes) use forward time differencing and the MPDATA for advection. Dynamic variables, u, v and w, use a second-order accurate advection scheme and a leapfrog time integration (kinetic energy semi-conserving method). Short-wave (solar) and long-wave radiation as well as a subgrid-scale TKE turbulence scheme are also included in the model. Details of the model can be found in Tao and Simpson (1993) and Tao et al. (2003). 2.2 Microphysics (Bin Model) The formulation of the explicit spectral-bin microphysical processes is based on solving stochastic kinetic equations for the size distribution functions of water droplets (cloud droplets and raindrops), and six types of ice particles: pristine ice crystals (columnar and plate-like), snow (dendrites and aggregates), graupel and frozen drops/hail. Each type is described by a special size distribution function containing 33 categories (bin

  11. A New WRF-Chem Treatment for Studying Regional Scale Impacts of Cloud-Aerosol Interactions in Parameterized Cumuli

    SciTech Connect (OSTI)

    Berg, Larry K.; Shrivastava, ManishKumar B.; Easter, Richard C.; Fast, Jerome D.; Chapman, Elaine G.; Liu, Ying

    2015-01-01T23:59:59.000Z

    A new treatment of cloud-aerosol interactions within parameterized shallow and deep convection has been implemented in WRF-Chem that can be used to better understand the aerosol lifecycle over regional to synoptic scales. The modifications to the model to represent cloud-aerosol interactions include treatment of the cloud dropletnumber mixing ratio; key cloud microphysical and macrophysical parameters (including the updraft fractional area, updraft and downdraft mass fluxes, and entrainment) averaged over the population of shallow clouds, or a single deep convective cloud; and vertical transport, activation/resuspension, aqueous chemistry, and wet removal of aerosol and trace gases in warm clouds. Thesechanges have been implemented in both the WRF-Chem chemistry packages as well as the Kain-Fritsch cumulus parameterization that has been modified to better represent shallow convective clouds. Preliminary testing of the modified WRF-Chem has been completed using observations from the Cumulus Humilis Aerosol Processing Study (CHAPS) as well as a high-resolution simulation that does not include parameterized convection. The simulation results are used to investigate the impact of cloud-aerosol interactions on the regional scale transport of black carbon (BC), organic aerosol (OA), and sulfate aerosol. Based on the simulations presented here, changes in the column integrated BC can be as large as -50% when cloud-aerosol interactions are considered (due largely to wet removal), or as large as +35% for sulfate in non-precipitating conditions due to the sulfate production in the parameterized clouds. The modifications to WRF-Chem version 3.2.1 are found to account for changes in the cloud drop number concentration (CDNC) and changes in the chemical composition of cloud-drop residuals in a way that is consistent with observations collected during CHAPS. Efforts are currently underway to port the changes described here to WRF-Chem version 3.5, and it is anticipated that they will be included in a future public release of WRF-Chem.

  12. Why chemistry? Chemistry is fundamental: it is the enabling science

    E-Print Network [OSTI]

    Sussex, University of

    Chemistry Why chemistry? Chemistry is fundamental: it is the enabling science that underlies many technology. A chemistry degree allows you to understand and to contribute to our future. Chemistry is challenging: understanding the very fabric of matter is both stimulating and rewarding. Studying chemistry

  13. Chemistry Division Department of Biological

    E-Print Network [OSTI]

    Heller, Barbara

    1 Chemistry Division Department of Biological and Chemical Sciences, Illinois Institute-13 Chemistry Division invites nominations for Kilpatrick Fellowship for the academic year 2012's Chemistry Department from 1947­1960. Mary Kilpatrick was a chemistry faculty member from 1947

  14. Chemistry and Biochemistry Scholarships

    E-Print Network [OSTI]

    Almor, Amit

    Chemistry and Biochemistry Scholarships Complete Scholarship Name Application Deadline Date Contact Endowment Fund To provide support for undergraduate biomedical research in the Department of Chemistry/or the purchase of supplies. Yes w/recommendation s from faculty Call goes out in February to all chemistry

  15. CHEMISTRY DEPARTMENT HANDBOOKFOR STUDENTS

    E-Print Network [OSTI]

    Hardy, Christopher R.

    CHEMISTRY DEPARTMENT HANDBOOKFOR STUDENTS Millersville University Millersville, Pennsylvania in the ChemistryDepartment. It brings together material not collected in other places and is not meant Resources 2 Programs in Chemistry and The General Education Curriculum Record Form 3 The Major Requirements

  16. Chemistry and Biochemistry Scholarships

    E-Print Network [OSTI]

    Almor, Amit

    Chemistry and Biochemistry Scholarships Complete Scholarship Name Application Deadline Date Contact to Chemistry and Biochemistry entering graduate students who have asked for consideration to serve as research@chem.sc.edu Hiram and Lawanda Allen Scholarship for Excellence in Chemistry This award is given to a graduating

  17. Adam Benoit Medicinal Chemistry

    E-Print Network [OSTI]

    Thomas, David D.

    #12;Adam Benoit Medicinal Chemistry Ph.D. Thesis Title: Synthesis and Evaluation of Acridine Country: United States #12;Amit Gangar Medicinal Chemistry Ph.D. Thesis Title: Design and Development Wagner Home Country: India #12;Dan Wang Medicinal Chemistry M.S. Thesis Title: Synthesis and Evaluation

  18. AERONET: The Aerosol Robotic Network

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    AERONET collaboration provides globally distributed observations of spectral aerosol optical Depth (AOD), inversion products, and precipitable water in diverse aerosol regimes. Aerosol optical depth data are computed for three data quality levels: Level 1.0 (unscreened), Level 1.5 (cloud-screened), and Level 2.0 (cloud screened and quality-assured). Inversions, precipitable water, and other AOD-dependent products are derived from these levels and may implement additional quality checks.[Copied from http://aeronet.gsfc.nasa.gov/new_web/system_descriptions.html

  19. Organic Chemistry 51B -Winter 2013 Organic Chemistry Peer Tutoring Program Chemistry 51B Reactions List

    E-Print Network [OSTI]

    Rose, Michael R.

    Organic Chemistry 51B - Winter 2013 Organic Chemistry Peer Tutoring Program Chemistry 51B Reactions(s). Chapter 7: Nucleophilic Substitution + + NaOH CH3O- #12;Organic Chemistry 51B - Winter 2013 Organic Chemistry Peer Tutoring Program Chapter 8: Elimination Reactions #12;Organic Chemistry 51B - Winter 2013

  20. 8, 68456901, 2008 Aerosol optical

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of solar radiation by atmospheric aerosols is a key el- ement of the Earth's radiative energy balance, Germany 2 Helmholtz Center Munich, German Research Center for Environmental Health, Institute

  1. Aerosol penetration through transport lines

    E-Print Network [OSTI]

    Dileep, V.R.

    1996-01-01T23:59:59.000Z

    to predict aerosol penetration thrush shrouded probes and transition fitting('s. Experimnents were carried Out to validate the code. The experiments were carried out for different flow rates for a particle size of IO lam aerodynamic diameter (AD...

  2. 6, 55435583, 2006 Aerosol nucleation

    E-Print Network [OSTI]

    Boyer, Edmond

    and cloud cover via the second indirect aerosol effect that would explain observed variations in global cloud cover. We esti- mate that the variation in radiative forcing resulting from a response of clouds

  3. EAS/CEE 6795 Atmospheric Aerosols Fall 2011

    E-Print Network [OSTI]

    Weber, Rodney

    EAS/CEE 6795 Atmospheric Aerosols Fall 2011 Mon Wed Fri ­ 11 concepts of aerosol physics with applications to atmospheric aerosols. Text Book: Hinds, Aerosol Technology: Properties, behavior and measurement of airborne particles

  4. Global observations of desert dust and biomass burning aerosols

    E-Print Network [OSTI]

    Graaf, Martin de

    Global observations of desert dust and biomass burning aerosols Martin de Graaf KNMI #12; Outline · Absorbing Aerosol Index - Theory · Absorbing Aerosol Index - Reality · Biomass burning and desert dust observations from GOME and SCIAMACHY · Conclusions and Outlook #12; · Absorbing Aerosol

  5. Method for producing monodisperse aerosols

    DOE Patents [OSTI]

    Ortiz, Lawrence W. (Los Alamos, NM); Soderholm, Sidney C. (Pittsford, NY)

    1990-01-01T23:59:59.000Z

    An aerosol generator is described which is capable of producing a monodisperse aerosol within narrow limits utilizing an aqueous solution capable of providing a high population of seed nuclei and an organic solution having a low vapor pressure. The two solutions are cold nebulized, mixed, vaporized, and cooled. During cooling, particles of the organic vapor condense onto the excess seed nuclei, and grow to a uniform particle size.

  6. AEROSOL, CLOUDS, AND CLIMATE CHANGE

    SciTech Connect (OSTI)

    SCHWARTZ, S.E.

    2005-09-01T23:59:59.000Z

    Earth's climate is thought to be quite sensitive to changes in radiative fluxes that are quite small in absolute magnitude, a few watts per square meter, and in relation to these fluxes in the natural climate. Atmospheric aerosol particles exert influence on climate directly, by scattering and absorbing radiation, and indirectly by modifying the microphysical properties of clouds and in turn their radiative effects and hydrology. The forcing of climate change by these indirect effects is thought to be quite substantial relative to forcing by incremental concentrations of greenhouse gases, but highly uncertain. Quantification of aerosol indirect forcing by satellite- or ground-based remote sensing has proved quite difficult in view of inherent large variation in the pertinent observables such as cloud optical depth, which is controlled mainly by liquid water path and only secondarily by aerosols. Limited work has shown instances of large magnitude of aerosol indirect forcing, with local instantaneous forcing upwards of 50 W m{sup 66}-2. Ultimately it will be necessary to represent aerosol indirect effects in climate models to accurately identify the anthropogenic forcing at present and over secular time and to assess the influence of this forcing in the context of other forcings of climate change. While the elements of aerosol processes that must be represented in models describing the evolution and properties of aerosol particles that serve as cloud condensation particles are known, many important components of these processes remain to be understood and to be represented in models, and the models evaluated against observation, before such model-based representations can confidently be used to represent aerosol indirect effects in climate models.

  7. The effects of emission of anthropogenic chemical species on chemical and physical properties of aerosols

    SciTech Connect (OSTI)

    Lee, In Young

    1994-07-01T23:59:59.000Z

    Numerical studies have been carried out to examine the effects of chemically reactive trace gases emitted into the atmosphere on the evolution of chemical species concentrations, on the chemical composition and size distribution of airborne particles, and on optical properties of aerosols. Argonne`s chemistry module has been modified by refining the treatment of gas-to-particle conversion. The changes in size distribution and chemical composition of aerosols are calculated with consideration of heteramolecular diffusion and coagulation. Results of the 24 h real-time simulation indicate that the maximum oxidation rate of sulfur dioxide is about 0.4% h{sup {minus}1}; that the total aerosol volume increases with the increase in relative humidity by as much as 36% (due mainly to the collection of sulfuric acid embryos by preexisting particles); and that the surface area, a measure of optical depth, increases with the increase in relative humidity by as much as 27%.

  8. TCD-IISc Symposium "Chemistry & Chemical Biology"

    E-Print Network [OSTI]

    O'Mahony, Donal E.

    actinide chemistry, with a focus on coordination and organometallic uranium chemistry. Paula ColavitaTCD-IISc Symposium "Chemistry & Chemical Biology" Trinity College Clive Williams, Dean of Chemistry. Research areas include supramolecular organic and inorganic chemistry and medicinal chemistry

  9. Climate effects of anthropogenic sulfate: Simulations from a coupled chemistry/climate model

    SciTech Connect (OSTI)

    Chuang, C.C.; Penner, J.E.; Taylor, K.E.; Walton, J.J.

    1993-09-01T23:59:59.000Z

    In this paper, we use a more comprehensive approach by coupling a climate model with a 3-D global chemistry model to investigate the forcing by anthropogenic aerosol sulfate. The chemistry model treats the global-scale transport, transformation, and removal of SO{sub 2}, DMS and H{sub 2}SO{sub 4} species in the atmosphere. The mass concentration of anthropogenic sulfate from fossil fuel combustion and biomass burning is calculated in the chemistry model and provided to the climate model where it affects the shortwave radiation. We also investigate the effect, with cloud nucleation parameterized in terms of local aerosol number, sulfate mass concentration and updraft velocity. Our simulations indicate that anthropogenic sulfate may result in important increases in reflected solar radiation, which would mask locally the radiative forcing from increased greenhouse gases. Uncertainties in these results will be discussed.

  10. Exploring Tuning Strategies for Quantum Chemistry Computations

    E-Print Network [OSTI]

    Sosonkina, Masha

    to an efficient execution. General Atomic and Molecular Electronic Structure (GAMESS), used for ab-initio molecular quantum chemistry calculations, uses NICAN for dynamically making adaptations so as to improve calculations. These calculations include a wide range of Hartree-Fock (HF) wave function (RHF, ROHF, UHF, GVB

  11. Parameter exploration of optically trapped liquid aerosols

    E-Print Network [OSTI]

    D. R. Burnham; P. J. Reece; D. McGloin

    2010-06-24T23:59:59.000Z

    When studying the motion of optically trapped particles on the $\\mu s$ time scale, in low viscous media such as air, inertia cannot be neglected. Resolution of unusual and interesting behaviour not seen in colloidal trapping experiments is possible. In attempt to explain the phenomena we use power spectral methods to perform a parameter study of the Brownian motion of optically trapped liquid aerosol droplets concentrated around the critically damped regime. We present evidence that the system is suitably described by a simple harmonic oscillator model which must include a description of Fax\\'{e}n's correction, but not necessarily frequency dependent hydrodynamic corrections to Stokes' law. We also provide results describing how the system behaves under several variables and discuss the difficulty in decoupling the parameters responsible for the observed behaviour. We show that due to the relatively low dynamic viscosity and high trap stiffness it is easy to transfer between over- and under-damped motion by experimentally altering either trap stiffness or damping. Our results suggest stable aerosol trapping may be achieved in under-damped conditions, but the onset of deleterious optical forces at high trapping powers prevents the probing of the upper stability limits due to Brownian motion.

  12. Vapor scavenging by atmospheric aerosol particles

    SciTech Connect (OSTI)

    Andrews, E.

    1996-05-01T23:59:59.000Z

    Particle growth due to vapor scavenging was studied using both experimental and computational techniques. Vapor scavenging by particles is an important physical process in the atmosphere because it can result in changes to particle properties (e.g., size, shape, composition, and activity) and, thus, influence atmospheric phenomena in which particles play a role, such as cloud formation and long range transport. The influence of organic vapor on the evolution of a particle mass size distribution was investigated using a modified version of MAEROS (a multicomponent aerosol dynamics code). The modeling study attempted to identify the sources of organic aerosol observed by Novakov and Penner (1993) in a field study in Puerto Rico. Experimentally, vapor scavenging and particle growth were investigated using two techniques. The influence of the presence of organic vapor on the particle`s hydroscopicity was investigated using an electrodynamic balance. The charge on a particle was investigated theoretically and experimentally. A prototype apparatus--the refractive index thermal diffusion chamber (RITDC)--was developed to study multiple particles in the same environment at the same time.

  13. Surveys of research in the Chemistry Division, Argonne National Laboratory

    SciTech Connect (OSTI)

    Grazis, B.M. (ed.)

    1992-01-01T23:59:59.000Z

    Research reports are presented on reactive intermediates in condensed phase (radiation chemistry, photochemistry), electron transfer and energy conversion, photosynthesis and solar energy conversion, metal cluster chemistry, chemical dynamics in gas phase, photoionization-photoelectrons, characterization and reactivity of coal and coal macerals, premium coal sample program, chemical separations, heavy elements coordination chemistry, heavy elements photophysics/photochemistry, f-electron interactions, radiation chemistry of high-level wastes (gas generation in waste tanks), ultrafast molecular electronic devices, and nuclear medicine. Separate abstracts have been prepared. Accelerator activites and computer system/network services are also reported.

  14. Surveys of research in the Chemistry Division, Argonne National Laboratory

    SciTech Connect (OSTI)

    Grazis, B.M. [ed.

    1992-11-01T23:59:59.000Z

    Research reports are presented on reactive intermediates in condensed phase (radiation chemistry, photochemistry), electron transfer and energy conversion, photosynthesis and solar energy conversion, metal cluster chemistry, chemical dynamics in gas phase, photoionization-photoelectrons, characterization and reactivity of coal and coal macerals, premium coal sample program, chemical separations, heavy elements coordination chemistry, heavy elements photophysics/photochemistry, f-electron interactions, radiation chemistry of high-level wastes (gas generation in waste tanks), ultrafast molecular electronic devices, and nuclear medicine. Separate abstracts have been prepared. Accelerator activites and computer system/network services are also reported.

  15. Assessing regional scale predictions of aerosols, marine stratocumulus, and their interactions during VOCALS-REx using WRF-Chem

    SciTech Connect (OSTI)

    Yang Q.; Lee Y.; Gustafson Jr., W. I.; Fast, J. D.; Wang, H.; Easter, R. C.; Morrison, H.; Chapman, E. G.; Spak, S. N.; Mena-Carrasco, M. A.

    2011-12-02T23:59:59.000Z

    This study assesses the ability of the recent chemistry version (v3.3) of the Weather Research and Forecasting (WRF-Chem) model to simulate boundary layer structure, aerosols, stratocumulus clouds, and energy fluxes over the Southeast Pacific Ocean. Measurements from the VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) and satellite retrievals (i.e., products from the MODerate resolution Imaging Spectroradiometer (MODIS), Clouds and Earth's Radiant Energy System (CERES), and GOES-10) are used for this assessment. The Morrison double-moment microphysics scheme is newly coupled with interactive aerosols in the model. The 31-day (15 October-16 November 2008) WRF-Chem simulation with aerosol-cloud interactions (AERO hereafter) is also compared to a simulation (MET hereafter) with fixed cloud droplet number concentrations in the microphysics scheme and simplified cloud and aerosol treatments in the radiation scheme. The well-simulated aerosol quantities (aerosol number, mass composition and optical properties), and the inclusion of full aerosol-cloud couplings lead to significant improvements in many features of the simulated stratocumulus clouds: cloud optical properties and microphysical properties such as cloud top effective radius, cloud water path, and cloud optical thickness. In addition to accounting for the aerosol direct and semi-direct effects, these improvements feed back to the simulation of boundary-layer characteristics and energy budgets. Particularly, inclusion of interactive aerosols in AERO strengthens the temperature and humidity gradients within the capping inversion layer and lowers the marine boundary layer (MBL) depth by 130 m from that of the MET simulation. These differences are associated with weaker entrainment and stronger mean subsidence at the top of the MBL in AERO. Mean top-of-atmosphere outgoing shortwave fluxes, surface latent heat, and surface downwelling longwave fluxes are in better agreement with observations in AERO, compared to the MET simulation. Nevertheless, biases in some of the simulated meteorological quantities (e.g., MBL temperature and humidity) and aerosol quantities (e.g., underestimations of accumulation mode aerosol number) might affect simulated stratocumulus and energy fluxes over the Southeastern Pacific, and require further investigation. The well-simulated timing and outflow patterns of polluted and clean episodes demonstrate the model's ability to capture daily/synoptic scale variations of aerosol and cloud properties, and suggest that the model is suitable for studying atmospheric processes associated with pollution outflow over the ocean. The overall performance of the regional model in simulating mesoscale clouds and boundary layer properties is encouraging and suggests that reproducing gradients of aerosol and cloud droplet concentrations and coupling cloud-aerosol-radiation processes are important when simulating marine stratocumulus over the Southeast Pacific.

  16. Aerosol Science and Technology, 43:641652, 2009 Copyright American Association for Aerosol Research

    E-Print Network [OSTI]

    Aerosol Science and Technology, 43:641­652, 2009 Copyright © American Association for Aerosol is the irreversibility of the hygroscopic growth fac- tor of aerosol particles. The instrument uses the hysteresis for ideal instrument performance in application to a test aerosol of fully deliquesce- able particles

  17. Aerosol Science and Technology, 43:799807, 2009 Copyright American Association for Aerosol Research

    E-Print Network [OSTI]

    Aerosol Science and Technology, 43:799­807, 2009 Copyright © American Association for Aerosol and Efflorescence of Potassium Salts Relevant to Biomass-Burning Aerosol Particles Evelyn J. Freney,1 Scot T. Martin mate- rial into the atmosphere. Such aerosol particles affect the climate in part because

  18. Aerosol Science and Technology, 47:9398, 2013 Copyright C American Association for Aerosol Research

    E-Print Network [OSTI]

    Huang, Jiaxing

    Aerosol Science and Technology, 47:93­98, 2013 Copyright C American Association for Aerosol of Pt-Nanoparticles-Laden Graphene Crumples by Aerosol Spray Pyrolysis and Evaluation of aqueous chloroplatinic acid (H2PtCl6) and graphene oxide (GO) sheets via aerosol spray pyrol- ysis (ASP

  19. Simulating aerosols using a chemical transport model with assimilation of satellite aerosol retrievals

    E-Print Network [OSTI]

    Zender, Charles

    Simulating aerosols using a chemical transport model with assimilation of satellite aerosol for simulating aerosols has been developed using a chemical transport model together with an assimilation of satellite aerosol retrievals. The methodology and model components are described in this paper

  20. Aerosol Science and Technology, 46:12391245, 2012 Copyright C American Association for Aerosol Research

    E-Print Network [OSTI]

    Nizkorodov, Sergey

    Aerosol Science and Technology, 46:1239­1245, 2012 Copyright C American Association for Aerosol of Surfactants in Nanoparticles Produced by an Electrospray Aerosol Generator Amanda C. MacMillan,1 John B, USA Electrospray aerosol generators (EAGs) disperse conducting solutions into air, promptly neutralize

  1. Aerosol Science and Technology, 41:10891101, 2007 Copyright c American Association for Aerosol Research

    E-Print Network [OSTI]

    Aerosol Science and Technology, 41:1089­1101, 2007 Copyright c American Association for Aerosol Interferometric Aerosol Absorption Spectrometry Arthur Sedlacek and Jeonghoon Lee Brookhaven National Laboratory, Atmospheric Sciences, Upton, New York, USA Aerosol light absorption still remains a difficult quantity to mea

  2. Aerosol Science and Technology, 40:97106, 2006 Copyright c American Association for Aerosol Research

    E-Print Network [OSTI]

    Aerosol Science and Technology, 40:97­106, 2006 Copyright c American Association for Aerosol the aerosol particles, namely by vaporizing and condensing granular sodium chloride and by electrospraying materials are available for this article. Go to the publisher's online edition of Aerosol Science and Tech

  3. Aerosol Science and Technology, 46:937949, 2012 Copyright C American Association for Aerosol Research

    E-Print Network [OSTI]

    Aerosol Science and Technology, 46:937­949, 2012 Copyright C American Association for Aerosol Distributions following Condensational Growth in Continuous Flow Aerosol Reactors as Derived from Residence Time Distributions: Theoretical Development and Application to Secondary Organic Aerosol Mikinori Kuwata and Scot T

  4. Aerosol Science and Technology, 44:11401145, 2010 Copyright American Association for Aerosol Research

    E-Print Network [OSTI]

    Huang, Jiaxing

    Aerosol Science and Technology, 44:1140­1145, 2010 Copyright © American Association for Aerosol-Assembly of Nanoparticles in Evaporating Aerosol Droplets: Preparation of Nanoporous Pt/TiO2 Composite Particles Hee Dong, USA Nanoporous Pt/TiO2 micro-particles were synthesized via an aerosol assisted co-assembly (AACA

  5. X-ray Vision for Aerosol Scientists: LCLS Snapshots of Soot (Narrated)

    ScienceCinema (OSTI)

    None

    2014-06-03T23:59:59.000Z

    This short conceptual animation depicts how scientists can now simultaneously capture fractal morphology (structure), chemical composition and nanoscale imagery of individual aerosol particles in flight. These particles, known as "PM2.5" because they are smaller than 2.5 microns in diameter, affect climate by interacting with sunlight and impact human health by entering the lungs. The single LCLS laser pulses travel to the Atomic, Molecular and Optical Sciences (AMO) laboratory in the Near Experimental Hall. As we zoom in, we see deep inside a simplified aerosol inlet, where the complex fractal structure of the soot particles, each one completely unique, is shown. Individual soot particles are then delivered into the pulses of the LCLS beam, which destroys them. X-rays are scattered to the detector before the particle is destroyed, giving information about the morphology of the particle. Ion fragments released in the explosion are sent into a mass spectrometer, which measures their mass-to-charge ratio -- giving scientists information about the chemical composition of the particle. Many different particles are analyzed in this manner, allowing scientists to probe variations in the particles due to changes in their environment before being sent through the aerosol inlet. The final visual of aerosols emitted from a factory is representative of the goal that such LCLS aerosol dynamics experiments can provide critical feedback into modeling and understanding combustion, aerosol processes in manufacturing or aerosol effects on climate change.

  6. Microphysical Effects Determine Macrophysical Response for Aerosol Impacts on Deep Convective Clouds

    SciTech Connect (OSTI)

    Fan, Jiwen; Leung, Lai-Yung R.; Rosenfeld, Daniel; Chen, Qian; Li, Zhanqing; Zhang, Jinqiang; Yan, Hongru

    2013-11-26T23:59:59.000Z

    Deep convective clouds (DCCs) play a crucial role in the general circulation and energy and hydrological cycle of our climate system. Anthropogenic and natural aerosol particles can influence DCCs through changes in cloud properties, precipitation regimes, and radiation balance. Modeling studies have reported both invigoration and suppression of DCCs by aerosols, but none has fully quantified aerosol impacts on convection life cycle and radiative forcing. By conducting multiple month-long cloud-resolving simulations with spectral-bin cloud microphysics that capture the observed macro- and micro-physical properties of summer convective clouds in the tropics and mid-latitudes, this study provides the first comprehensive look at how aerosols affect cloud cover, cloud top height (CTH), and radiative forcing. Observations validate these simulation results. We find that microphysical aerosol effects contribute predominantly to increased cloud cover and CTH by inducing larger amount of smaller but longer lasting ice particles in the stratiform/anvils of DCCs with dynamical aerosol effects contributing at most ~ 1/4 of the total increase of cloud cover. The overall effect is a radiative warming in the atmosphere (3 to 5 W m-2) with strong surface cooling (-5 to -8 W m-2). Herein we clearly identified mechanisms more important than and additional to the invigoration effects hypothesized previously that explain the consistent signatures of increased cloud tops area and height by aerosols in DCCs revealed by observations.

  7. X-ray Vision for Aerosol Scientists: LCLS Snapshots of Soot (Narrated)

    SciTech Connect (OSTI)

    None

    2012-10-22T23:59:59.000Z

    This short conceptual animation depicts how scientists can now simultaneously capture fractal morphology (structure), chemical composition and nanoscale imagery of individual aerosol particles in flight. These particles, known as "PM2.5" because they are smaller than 2.5 microns in diameter, affect climate by interacting with sunlight and impact human health by entering the lungs. The single LCLS laser pulses travel to the Atomic, Molecular and Optical Sciences (AMO) laboratory in the Near Experimental Hall. As we zoom in, we see deep inside a simplified aerosol inlet, where the complex fractal structure of the soot particles, each one completely unique, is shown. Individual soot particles are then delivered into the pulses of the LCLS beam, which destroys them. X-rays are scattered to the detector before the particle is destroyed, giving information about the morphology of the particle. Ion fragments released in the explosion are sent into a mass spectrometer, which measures their mass-to-charge ratio -- giving scientists information about the chemical composition of the particle. Many different particles are analyzed in this manner, allowing scientists to probe variations in the particles due to changes in their environment before being sent through the aerosol inlet. The final visual of aerosols emitted from a factory is representative of the goal that such LCLS aerosol dynamics experiments can provide critical feedback into modeling and understanding combustion, aerosol processes in manufacturing or aerosol effects on climate change.

  8. Single particle characterization, source apportionment, and aging effects of ambient aerosols in Southern California

    E-Print Network [OSTI]

    Shields, Laura Grace

    2008-01-01T23:59:59.000Z

    detection efficiencies of aerosol time of flight masscomposition of ambient aerosol particles. Environmentalsize dependent response of aerosol counters, Atmospheric

  9. Aerosol cluster impact and break-up : model and implementation.

    SciTech Connect (OSTI)

    Lechman, Jeremy B.

    2010-10-01T23:59:59.000Z

    In this report a model for simulating aerosol cluster impact with rigid walls is presented. The model is based on JKR adhesion theory and is implemented as an enhancement to the granular (DEM) package within the LAMMPS code. The theory behind the model is outlined and preliminary results are shown. Modeling the interactions of small particles is relevant to a number of applications (e.g., soils, powders, colloidal suspensions, etc.). Modeling the behavior of aerosol particles during agglomeration and cluster dynamics upon impact with a wall is of particular interest. In this report we describe preliminary efforts to develop and implement physical models for aerosol particle interactions. Future work will consist of deploying these models to simulate aerosol cluster behavior upon impact with a rigid wall for the purpose of developing relationships for impact speed and probability of stick/bounce/break-up as well as to assess the distribution of cluster sizes if break-up occurs. These relationships will be developed consistent with the need for inputs into system-level codes. Section 2 gives background and details on the physical model as well as implementations issues. Section 3 presents some preliminary results which lead to discussion in Section 4 of future plans.

  10. Optimization of aerosol penetration through transport lines

    E-Print Network [OSTI]

    Wong Luque, Fermin Samuel

    1992-01-01T23:59:59.000Z

    function of Reynolds number for the aerosol transport system of Strom. Tube diameter = 15. 9 mm. 69 Figure Page 16. Comparison of model, experiments and Strom's data for aerosol penetration through the transport system of Strom. Tube diameter = 15. 9... mm, AED = 8 nm. 70 17. Comparison of model and experiments for aerosol penetration through the transport system of Strom. Tube diameter = 15. 9 mm, AED = 10 pm. . 71 18. Comparison of model, experiments and Strom's data for aerosol penetration...

  11. 8, 7194, 2008 Sea salt aerosol

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ACPD 8, 71­94, 2008 Sea salt aerosol refractive indices R. Irshad et al. Title Page Abstract Discussions Laboratory measurements of the optical properties of sea salt aerosol R. Irshad 1 , R. G. Grainger salt aerosol refractive indices R. Irshad et al. Title Page Abstract Introduction Conclusions

  12. 4, 20552088, 2004 Aerosol-ozone

    E-Print Network [OSTI]

    Boyer, Edmond

    ACPD 4, 2055­2088, 2004 Aerosol-ozone correlations during dust transport episodes P. Bonasoni et al and Physics Discussions Aerosol-ozone correlations during dust transport episodes P. Bonasoni1 , P.bonasoni@isac.cnr.it) 2055 #12;ACPD 4, 2055­2088, 2004 Aerosol-ozone correlations during dust transport episodes P. Bonasoni

  13. ATI TDA 5A aerosol generator evaluation

    SciTech Connect (OSTI)

    Gilles, D.A.

    1998-07-27T23:59:59.000Z

    Oil based aerosol ``Smoke`` commonly used for testing the efficiency and penetration of High Efficiency Particulate Air filters (HEPA) and HEPA systems can produce flammability hazards that may not have been previously considered. A combustion incident involving an aerosol generator has caused an investigation into the hazards of the aerosol used to test HEPA systems at Hanford.

  14. 5, 50075038, 2005 Aerosol effect on

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    and Physics Discussions Aerosol effect on the distribution of solar radiation over the clear-sky global oceansACPD 5, 5007­5038, 2005 Aerosol effect on solar radiation from MODIS L. A. Remer and Y. J. Kaufman the reflected sunlight by the aerosol over global oceans in cloud free conditions. The MODIS high spatial

  15. CHEMISTRY 450 Spring, 2009

    E-Print Network [OSTI]

    Stuart, Steven J.

    CHEMISTRY 450 Spring, 2009 Gautam Bhattacharyya, 363 Hunter Labs, phone: 656-1356 gautamb. This course does NOT have a separate laboratory meeting time. Course Goals CH 450 is the Chemistry Capstone to change. #12;CH 450 Spring, 2009 -2- Course Outline (Tentative) Journal due dates are designated each week

  16. Real time infrared aerosol analyzer

    DOE Patents [OSTI]

    Johnson, Stanley A. (Countryside, IL); Reedy, Gerald T. (Bourbonnais, IL); Kumar, Romesh (Naperville, IL)

    1990-01-01T23:59:59.000Z

    Apparatus for analyzing aerosols in essentially real time includes a virtual impactor which separates coarse particles from fine and ultrafine particles in an aerosol sample. The coarse and ultrafine particles are captured in PTFE filters, and the fine particles impact onto an internal light reflection element. The composition and quantity of the particles on the PTFE filter and on the internal reflection element are measured by alternately passing infrared light through the filter and the internal light reflection element, and analyzing the light through infrared spectrophotometry to identify the particles in the sample.

  17. Marquette University Department of Chemistry

    E-Print Network [OSTI]

    Reid, Scott A.

    Analysis Inorganic Chemistry Lecture Inorganic Synthesis Lab #12;Our Curriculum Physical Chemistry Lecture.... Directly influence the lives of others? Develop new materials with enhanced flame- retardant properties

  18. CHEMISTRY 1010 CHEMISTRY, HUMANITY AND ENVIRONMENT

    E-Print Network [OSTI]

    Simons, Jack

    day to add classes, select C/NC option or to audit a class is Jan. 23. 3. The last day to withdraw. The University of Utah seeks to provide equal access to its programs, services and activities for people: Chemistry 1010 aims to promote understanding of the basic environmental ingredients, energy, atoms

  19. Review of models applicable to accident aerosols

    SciTech Connect (OSTI)

    Glissmeyer, J.A.

    1983-07-01T23:59:59.000Z

    Estimations of potential airborne-particle releases are essential in safety assessments of nuclear-fuel facilities. This report is a review of aerosol behavior models that have potential applications for predicting aerosol characteristics in compartments containing accident-generated aerosol sources. Such characterization of the accident-generated aerosols is a necessary step toward estimating their eventual release in any accident scenario. Existing aerosol models can predict the size distribution, concentration, and composition of aerosols as they are acted on by ventilation, diffusion, gravity, coagulation, and other phenomena. Models developed in the fields of fluid mechanics, indoor air pollution, and nuclear-reactor accidents are reviewed with this nuclear fuel facility application in mind. The various capabilities of modeling aerosol behavior are tabulated and discussed, and recommendations are made for applying the models to problems of differing complexity.

  20. Dynamic shape factors for hydox-generated plutonium dioxide-type non-sperical objects 

    E-Print Network [OSTI]

    Lohaus, James Harold

    1999-01-01T23:59:59.000Z

    The dynamic shape factors of HYDOX-generated plutonium dioxide-type non-spherical objects were estimated with computational methods. Leith's empirical methods were used to modify classical Stokes's law for aerosol dynamics (1987). The dynamic shape...

  1. Untangling the Chemical Evolution of Titan's Atmosphere and Surface -- From Homogeneous to Heterogeneous Chemistry

    SciTech Connect (OSTI)

    Kaiser, Ralf I.; Maksyutenko, Pavlo; Ennis, Courtney; Zhang, Fangtong; Gu, Xibin; Krishtal, Sergey P.; Mebel, Alexander M.; Kostko, Oleg; Ahmed, Musahid

    2010-03-16T23:59:59.000Z

    The arrival of the Cassini-Huygens probe at Saturn's moon Titan - the only Solar System body besides Earth and Venus with a solid surface and a thick atmosphere with a pressure of 1.4 atm at surface level - in 2004 opened up a new chapter in the history of Solar System exploration. The mission revealed Titan as a world with striking Earth-like landscapes involving hydrocarbon lakes and seas as well as sand dunes and lava-like features interspersed with craters and icy mountains of hitherto unknown chemical composition. The discovery of a dynamic atmosphere and active weather system illustrates further the similarities between Titan and Earth. The aerosol-based haze layers, which give Titan its orange-brownish color, are not only Titan's most prominent optically visible features, but also play a crucial role in determining Titan's thermal structure and chemistry. These smog-like haze layers are thought to be very similar to those that were present in Earth's atmosphere before life developed more than 3.8 billion years ago, absorbing the destructive ultraviolet radiation from the Sun, thus acting as 'prebiotic ozone' to preserve astrobiologically important molecules on Titan. Compared to Earth, Titan's low surface temperature of 94 K and the absence of liquid water preclude the evolution of biological chemistry as we know it. Exactly because of these low temperatures, Titan provides us with a unique prebiotic 'atmospheric laboratory' yielding vital clues - at the frozen stage - on the likely chemical composition of the atmosphere of the primitive Earth. However, the underlying chemical processes, which initiate the haze formation from simple molecules, have been not understood well to date.

  2. National Chemistry Week Theme: "Candy: The Sweet Side of Chemistry"

    E-Print Network [OSTI]

    Stephens, Jacqueline

    National Chemistry Week Theme: "Candy: The Sweet Side of Chemistry" Super Science Saturday Saturday-on chemistry and science demonstrations! All students & families are welcome! Fun & educational for all ages! Sponsored by: American Chemical Society LSU Department of Chemistry LSU Athletic Department Free admission

  3. I. Required core Chemistry Courses (1905 & 1925) Chemistry

    E-Print Network [OSTI]

    Advisor: Advisee: I. Required core Chemistry Courses (1905 & 1925) Chemistry CH 111 PY 211 _____ PY 212 _____ (or PY 242 _____ or PY 252 ______) II. Chemistry Options (one required) 1905 (Concentration in Chemistry) Option A (2 advanced CH courses, 401 or higher, only one may

  4. 7, 71717233, 2007 Aerosol absorption

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    black carbon refractive indices, new cloud radiative properties considering the effect of aerosol absorption and radiative forcing. The effect of the usage of more accurate effective medium approximations radiative properties re- sults in a small global annual-mean all-sky absorption of 0.05 W m-2 and a positive

  5. Impacts of aerosol-cloud interactions on past and future changes in tropospheric composition

    SciTech Connect (OSTI)

    Unger, N.; Menon, S.; Shindell, D. T.; Koch, D. M.

    2009-02-02T23:59:59.000Z

    The development of effective emissions control policies that are beneficial to both climate and air quality requires a detailed understanding of all the feedbacks in the atmospheric composition and climate system. We perform sensitivity studies with a global atmospheric composition-climate model to assess the impact of aerosols on tropospheric chemistry through their modification on clouds, aerosol-cloud interactions (ACI). The model includes coupling between both tropospheric gas-phase and aerosol chemistry and aerosols and liquid-phase clouds. We investigate past impacts from preindustrial (PI) to present day (PD) and future impacts from PD to 2050 (for the moderate IPCC A1B scenario) that embrace a wide spectrum of precursor emission changes and consequential ACI. The aerosol indirect effect (AIE) is estimated to be -2.0 Wm{sup -2} for PD-PI and -0.6 Wm{sup -2} for 2050-PD, at the high end of current estimates. Inclusion of ACI substantially impacts changes in global mean methane lifetime across both time periods, enhancing the past and future increases by 10% and 30%, respectively. In regions where pollution emissions increase, inclusion of ACI leads to 20% enhancements in in-cloud sulfate production and {approx}10% enhancements in sulfate wet deposition that is displaced away from the immediate source regions. The enhanced in-cloud sulfate formation leads to larger increases in surface sulfate across polluted regions ({approx}10-30%). Nitric acid wet deposition is dampened by 15-20% across the industrialized regions due to ACI allowing additional re-release of reactive nitrogen that contributes to 1-2 ppbv increases in surface ozone in outflow regions. Our model findings indicate that ACI must be considered in studies of methane trends and projections of future changes to particulate matter air quality.

  6. Detection of UV-absorbing aerosols using GOME and SCIAMACHY

    E-Print Network [OSTI]

    Graaf, Martin de

    Detection of UV-absorbing aerosols using GOME and SCIAMACHY Martin de Graaf KNMI #12; Outline · The Absorbing Aerosol Index: some theory · Detection of biomass burning aerosols and desert dust. -no clouds -no scattering aerosols Absorbing Aerosol Index AAI Algorithm LUT #12;GOME & SCIAMACHY

  7. DO AEROSOLS CHANGE CLOUD COVER AND AFFECT CLIMATE?

    E-Print Network [OSTI]

    Schwartz, Stephen E.

    BALANCE Global and annual average energy fluxes in watts per square meter Schwartz, 1996, modified from;AEROSOL INFLUENCES ON CLIMATE AND CLIMATE CHANGE #12;DMS #12;AEROSOL IN MEXICO CITY BASIN #12;AEROSOL IN MEXICO CITY BASIN Light scattering by aerosols decreases absorption of solar radiation. #12;AEROSOLS

  8. Aerosol observing system platform integration and AAF instrumentation

    SciTech Connect (OSTI)

    Springston, S.; Sedlacek, A.

    2010-03-15T23:59:59.000Z

    As part of the federal government’s 2009 American Recovery and Reinvestment Act (ARRA), the U.S. DOE Office of Science allocated funds for the capital upgrade of the Atmospheric Radiation Measurement (ARM) Climate Research Facility to improve and expand observational capabilities related to cloud and aerosol properties. The ARM Facility was established as a national user facility for the global scientific community to conduct a wide range of interdisciplinary science. Part of the ARRA-funded expansion of the ARM Facility includes four new Aerosol Observing Systems (AOS) to be designed, instrumented, and mentored by BNL. The enclosures will be customized SeaTainers. These new platforms ([AMF2]: ARM Mobile Facility-2; [TWP-D]: Tropical Western Pacific at Darwin; and [MAOS-A]/[MAOS-C]: Mobile Aerosol Observing System-Aerosol/-Chemistry) will provide a laboratory environment for fielding instruments to collect data on aerosol life cycle, microphysics, and optical/physical properties. The extensive instrument suite includes both established methods and initial deployments of new techniques to add breadth and depth to the AOS data sets. The platforms are designed: (1) to have all instruments pre-installed before deployment, allowing a higher measurement duty cycle; (2) with a standardized configuration improving the robustness of data inter-comparability; (3) to provide remote access capability for instrument mentors; and (4) to readily accommodate guest instrumentation. The first deployment of the AMF2 platform will be at the upcoming StormVEx campaign held at Steamboat Springs, Colorado, October 15, 2010–March 31, 2011 while the TWP-D AOS will be stationed at the ARM Darwin site. The maiden deployments of the MAOS-A and MAOS-C platforms will be during the Ganges Valley Experiment (GVAX) scheduled for April 2011–April 2012. In addition to the ground-based AOS platforms, thee major instrument builds for the AAF are also being undertaken (new trace gas package [NO, NOx, NOy, CO, O3, and SO2]; Scanning Mobility Particle Sampler [SMPS]; and Particle into Liquid Sampler [PILS]). The current status of the AOS platforms, instrument suites, instituted QA/QC activities, projected AOS VAPs, and inlet design, as well as still-unresolved issues, will be presented.

  9. Macromolecular Chemistry and Physics

    E-Print Network [OSTI]

    Guo, John Zhanhu

    Composites Laboratory (ICL), Dan F. Smith Department of Chemical Engineering, Lamar University, Beaumont, TX 77710, USA E-mail: zhanhu.guo@lamar.edu Y. Li, S. Wei Department of Chemistry and Biochemistry, Lamar

  10. Macromolecular Chemistry and Physics

    E-Print Network [OSTI]

    Guo, John Zhanhu

    Engineering, Lamar University, Beaumont, TX 77710, USA E-mail: suying.wei@lamar.edu; zhanhu.guo@lamar.edu Q. He, Prof. S. Wei Department of Chemistry and Biochemistry, Lamar University, Beaumont, TX 77710, USA

  11. Chemistry 455 Chemical Nanotechnology

    E-Print Network [OSTI]

    Rohs, Remo

    Chemistry 455 Chemical Nanotechnology 4 units Prof. Richard Brutchey, Fall 2014 (Lecture = 12:00­12:50 pm MWF) CHEM 455 is an upper-division undergraduate course in Chemical Nanotechnology. The intent

  12. Measurements of Aerosol Charge and Size Distribution for Graphite, Gold, Palladium, and Silver Nanoparticles

    SciTech Connect (OSTI)

    Simones, Matthew P.; Gutti, Veera R.; Meyer, Ryan M.; Loyalka, Sudarshan K.

    2011-11-01T23:59:59.000Z

    The role of charge on aerosol evolution and hence the nuclear source term has been an issue of interest, and there is a need for both experimental techniques and modeling for quantifying this role. Our focus here is on further exploration of a tandem differential mobility analyzer (TDMA) technique to simultaneously measure both the size and charge (positive, negative and neutral) dependent aerosol distributions. We have generated graphite, gold, silver, and palladium nanoparticles (aerosol) using a spark generator. We measure the electrical mobility-size distributions for these aerosols using a TDMA, and from these data we deduce the full charge-size distributions. We observe asymmetry in the particle size distributions for negative and positive charges. This asymmetry could have a bearing on the dynamics of charged aerosols, indicating that the assumption of symmetry for size distributions of negatively and positively charged particles in source term simulations may not be always appropriate. Also, the experimental technique should find applications in measurements of aerosol rate processes that are affected by both particle charge and size (e.g. coagulation, deposition, resuspension), and hence in modeling and simulation of the nuclear source term.

  13. Investigation of multiple scattering effects in aerosols. Final report, Sep 1978 - Dec 1979

    SciTech Connect (OSTI)

    Deepak, A.

    1980-05-01T23:59:59.000Z

    The results are presented of investigations on the various aspects of multiple scattering effects on visible and infrared laser beams transversing dense fog oil aerosols contained in a chamber (4' x 4' x 9'). The report briefly describes: (1) the experimental details and measurements (2) analytical representation of the aerosol size distribution data by two analytical models (the regularized power law distribution and the inverse modified gamma distribution) (3) retrieval of aerosol size distributions from multispectral optical depth measurements by two methods (the two and three parameter fast table search methods and the nonlinear least squares method) (4) modeling of the effects of aerosol microphysical (coagulation and evaporation) and dynamical processes (gravitational settling) on the temporal behavior of aerosol size distribution, and hence on the extinction of four laser beams with wavelengths 0.44, 0.6328, 1.15, and 3.39 micrometers and (5) the exact and approximate formulations for four methods for computing the effects of multiple scattering on the transmittance of laser beams in dense aerosols, all of which are based on the solution of the radiative transfer equation under the small angle approximation.

  14. Intercomparison of 14C Analysis of Carbonaceous Aerosols: Exercise 2009

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    analysis of carbonaceous aerosols: recent developments.Source apportionment of aerosols by 14 C measurements inAnalysis of Carbonaceous Aerosols Table 2a 14 C(TC) results

  15. Enhanced photolysis in aerosols: evidence for important surface effects.

    E-Print Network [OSTI]

    Nissenson, Paul; Knox, Christopher J H; Finlayson-Pitts, Barbara J; Phillips, Leon F; Dabdub, Donald

    2006-01-01T23:59:59.000Z

    irradiated for 30 s in the aerosol phase, (b) Mo(CO) 6 in 1-irradiation for both aerosols and the bulk-liquid solution.Enhanced photolysis in aerosols: evidence for important

  16. Remote sensing of terrestrial tropospheric aerosols from aircraft and satellites

    E-Print Network [OSTI]

    Remote sensing of terrestrial tropospheric aerosols from aircraft and satellites M I Mishchenko1 instruments suitable for aerosol remote sensing and give examples of aerosol retrievals obtained forcing directly by absorbing and reflecting sunlight, thereby cooling or heating the atmosphere

  17. Hygroscopic growth of submicron and supermicron aerosols in the marine boundary layer

    E-Print Network [OSTI]

    balance and climate directly through absorption and scattering of the incoming solar radiation and indirectly through modification of cloud properties [Intergovernmental Panel on Climate Change, 2007 behaviors of the dynamic and complex atmospheric aerosol consisting of particles with a wide range of sizes

  18. Aerosol Science 32 (2001) 14791504 www.elsevier.com/locate/jaerosci

    E-Print Network [OSTI]

    Zachariah, Michael R.

    controlled internal phase segregation during aerosol coagulation H. Struchtrup 1 , M. Luskin, M. R. Zachariah a monodisperse particle size distribution. The dynamical behavior of such a system is presented. c 2001 Elsevier and space of the particle size distribution function, which can include all the driving forces

  19. Aerosol Science 34 (2003) 189209 www.elsevier.com/locate/jaerosci

    E-Print Network [OSTI]

    the size distribution. Thus the QMOM has become a viable candidate for modeling aerosols under very general dynamics; Moment methods; Coagulation; Self-preserving distributions 1. Introduction The accurate and e explicitly represent the particle size distribution using either discrete bins (the sectional approach

  20. A Model for Kinetically Controlled Internal Phase Segregation During Aerosol Coagulation

    E-Print Network [OSTI]

    A Model for Kinetically Controlled Internal Phase Segregation During Aerosol Coagulation H size distribution. The dynamical behavior of such a system is presented. 1 Introduction The evolution). The GDE has been employed to characterize the behavior in time and space of the particle size distribution

  1. Chemistry Student Handbook College of Science

    E-Print Network [OSTI]

    Hickman, Mark

    Chemistry Student Handbook College of Science React. Science #12;Contents 2 Welcome to the Department of Chemistry 2 Course Advice 3 What is Chemistry? 4 Career Profiles in Chemistry 5 An Undergraduate Degree in Chemistry 6 Chemistry Streams 13 Chemistry Honours Programme 14 Research

  2. Chemistry Division annual progress report for period ending April 30, 1993

    SciTech Connect (OSTI)

    Poutsma, M.L.; Ferris, L.M.; Mesmer, R.E.

    1993-08-01T23:59:59.000Z

    The Chemistry Division conducts basic and applied chemical research on projects important to DOE`s missions in sciences, energy technologies, advanced materials, and waste management/environmental restoration; it also conducts complementary research for other sponsors. The research are arranged according to: coal chemistry, aqueous chemistry at high temperatures and pressures, geochemistry, chemistry of advanced inorganic materials, structure and dynamics of advanced polymeric materials, chemistry of transuranium elements and compounds, chemical and structural principles in solvent extraction, surface science related to heterogeneous catalysis, photolytic transformations of hazardous organics, DNA sequencing and mapping, and special topics.

  3. Ultrafine calcium aerosol: Generation and use as a sorbent for sulfur in coal combustion. Volume 1, Experimental work: Final report, August 1, 1988--October 31, 1991

    SciTech Connect (OSTI)

    Alam, M.K.; Nahar, N.U.; Stewart, G.D.; Prudich, M.E. [comps.] [Ohio Coal Research Center, Athens, OH (United States)

    1991-11-01T23:59:59.000Z

    Studies conducted at Ohio University and elsewhere have demonstrated that ultrafine aerosols, which have the highest surface area per unit mass, have enhanced potential to efficiently remove sulfur dioxide form combustion gases. Therefore it is proposed to generate a very fine aerosol calcium-rich sorbent (or similar aerosols) for gas conditioning. The aerosol will be generated by vaporization of the sorbent compound and subsequent homogeneous nucleation. In experimental studies liquids as well as solids will be converted into ultrafine aerosols by using suitable aerosol generator. The aerosol generator could be a simple bubbler or a flame spray jet using powders of calcium ``Compounds. Studies will then be carried out, to determine the dynamics of sulfur dioxide capture by the ultrafine aerosol. The primary objective of this research was to generate fine aerosols and to use them for coal combustion SO{sub 2}/NO{sub x} gas removal purposes. From the background study on the dry scrubbing system, it can be concluded that the most important experimental parameters are addition ratio, reactor temperature, residence time, total inlet flow rate and inlet SO{sub 2} concentration. Addition ratio is the inlet molar ratio of calcium to sulfur. Before any experimentation, it was necessary to decide and investigate the values of each of the parameters. Each of these parameters were investigated individually and the effects on SO{sub 2} removal were determined.

  4. Molecular Characterization of Organic Aerosols Using Nanospray...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in OA, which is important for understanding chemical aging phenomena. Citation: Roach PJ, J Laskin, and A Laskin.2010."Molecular Characterization of Organic Aerosols Using...

  5. Researchers Model Impact of Aerosols Over California

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Impact of Aerosols Over California Research may clarify the effectiveness of regional pollution controls May 28, 2013 | Tags: Climate Research, Hopper Contact: Linda Vu,...

  6. Photolytic processing of secondary organic aerosols dissolved...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    processing of secondary organic aerosols dissolved in cloud droplets. Abstract: The effect of UV irradiation on the molecular composition of aqueous extracts of secondary...

  7. Quantifying aerosol direct radiative effect with Multiangle Imaging Spectroradiometer observations: Top-of-atmosphere albedo change by aerosols based on land surface types

    E-Print Network [OSTI]

    Chen, Yang; Li, Qinbin; Kahn, Ralph A; Randerson, James T; Diner, David J

    2009-01-01T23:59:59.000Z

    coincident MISR and MODIS aerosol optical depths over land2003), Estimates of the spectral aerosol single scatteringalbedo and aerosol radiative effects during SAFARI 2000, J.

  8. Synergy between Secondary Organic Aerosols and Long Range Transport...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    between Secondary Organic Aerosols and Long Range Transport of Polycyclic Aromatic Hydrocarbons. Synergy between Secondary Organic Aerosols and Long Range Transport of Polycyclic...

  9. acid aerosol exposure: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Nenes, Athanasios 8 Neutralization of soil aerosol and its impact on the distribution of acid rain over east Asia Geosciences Websites Summary: Neutralization of soil aerosol and...

  10. Spectro-Microscopic Measurements of Carbonaceous Aerosol Aging...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of Carbonaceous Aerosol Aging in Central California. Abstract: Carbonaceous aerosols are responsible for large uncertainties in climate models, degraded visibility, and...

  11. Measurements of submicron aerosols in Houston, Texas during the...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of submicron aerosols in Houston, Texas during the 2009 SHARP field campaign. Measurements of submicron aerosols in Houston, Texas during the 2009 SHARP field campaign. Abstract:...

  12. Building America Webinar: Sealing of Home Enclosures with Aerosol...

    Energy Savers [EERE]

    Sealing of Home Enclosures with Aerosol Particles Building America Webinar: Sealing of Home Enclosures with Aerosol Particles This webinar was presented by research team Building...

  13. The dependence of ice microphysics on aerosol concentration in...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The dependence of ice microphysics on aerosol concentration in arctic mixed-phase stratus clouds during ISDAC and M-PACE. The dependence of ice microphysics on aerosol...

  14. Reduction in biomass burning aerosol light absorption upon humidificat...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in biomass burning aerosol light absorption upon humidification: Roles of inorganically-induced hygroscopicity, Reduction in biomass burning aerosol light absorption upon...

  15. aerosols iii morphologic: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Sciences Websites Summary: of aerosols. Keywords: metal waste recycling; aerosols; fire hazard; explosion hazard. 1. OVERVIEW ProductsRisks generated by the treatment of...

  16. Comparative Analysis of Urban Atmospheric Aerosol by Particle...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Analysis of Urban Atmospheric Aerosol by Particle-Induced X-ray Emission (PIXE), Proton Elastic Scattering Analysis Comparative Analysis of Urban Atmospheric Aerosol by...

  17. ambient aerosol concentrations: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    soluble in water: 2. Isolation of acid, neutral, and basic fractions by modified size Weber, Rodney 4 Ambient aerosol sampling using the Aerodyne Aerosol Mass Spectrometer...

  18. ambient ultrafine aerosols: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    soluble in water: 2. Isolation of acid, neutral, and basic fractions by modified size Weber, Rodney 4 Ambient aerosol sampling using the Aerodyne Aerosol Mass Spectrometer...

  19. aerosol flow reactor: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    APPROACH TO SPACEBORN HYPERSPECTRAL OPTICAL FLOW ESTIMATION ON DUST AEROSOLS Fabian E, Canada ABSTRACT The significant role dust aerosols play in the earth's climate sys- tem and...

  20. aerosol formation durint: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    XI, Universit de 86 8, 68456901, 2008 Aerosol optical Physics Websites Summary: of solar radiation by atmospheric aerosols is a key el- ement of the Earth's radiative energy...

  1. The Indirect and Semi-Direct Aerosol Campaign

    ScienceCinema (OSTI)

    Ghan, Steve

    2014-06-12T23:59:59.000Z

    Research projects like the Indirect and Semi-Direct Aerosol Campaign, or ISDAC, increase our knowledge of atmospheric aerosol particles and cloud physics.

  2. aerosol ratio program: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    contribute a major portion of atmospheric aerosol mass loading 5. The estimated global annual Liou, K. N. 2 Studying Clouds and Aerosols with Lidar Depolarization Ratio and...

  3. aerosol optical thickness: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of solar radiation by atmospheric aerosols is a key el- ement of the Earth's radiative energy balance and climate. The optical properties of aerosol particles are, however,...

  4. aerosol black carbon: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of solar radiation by atmospheric aerosols is a key el- ement of the Earth's radiative energy balance and climate. The optical properties of aerosol particles are, however,...

  5. The Indirect and Semi-Direct Aerosol Campaign

    SciTech Connect (OSTI)

    Ghan, Steve

    2014-03-24T23:59:59.000Z

    Research projects like the Indirect and Semi-Direct Aerosol Campaign, or ISDAC, increase our knowledge of atmospheric aerosol particles and cloud physics.

  6. aerosol samples collected: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    elements analysis of aerosol samples from some CiteSeer Summary: Aerosols deposits on filters from ten Romanian towns with different kinds and levels of industrial development...

  7. aerosol particles emitted: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    aerosols scatter and absorb solar, estimates of the impact of aerosols on visibility, the solar radiation balance, and crop production is presented. 1. INTRODUCTION The attenuation...

  8. aerosol size classification: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2006 Aerosol size Physics Websites Summary: ACPD 6, 10493-10522, 2006 Aerosol size distribution source identification T. W. Chan and M Esc Printer-friendly Version...

  9. aerosolized pentamidine effect: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ON CCN CONCENTRATION AND AEROSOL FIRST INDIRECT RADIATIVE composition, aerosol size distribution is the more dominant parameter on CCN activation Feingold, GRL 2003;...

  10. aerosol monitoring: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ON CCN CONCENTRATION AND AEROSOL FIRST INDIRECT RADIATIVE composition, aerosol size distribution is the more dominant parameter on CCN activation Feingold, GRL 2003;...

  11. aerosols radioactifs artificiels: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ON CCN CONCENTRATION AND AEROSOL FIRST INDIRECT RADIATIVE composition, aerosol size distribution is the more dominant parameter on CCN activation Feingold, GRL 2003;...

  12. aerosolized polymerized type: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ON CCN CONCENTRATION AND AEROSOL FIRST INDIRECT RADIATIVE composition, aerosol size distribution is the more dominant parameter on CCN activation Feingold, GRL 2003;...

  13. aerosol concentration enrichment: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ON CCN CONCENTRATION AND AEROSOL FIRST INDIRECT RADIATIVE composition, aerosol size distribution is the more dominant parameter on CCN activation Feingold, GRL 2003;...

  14. aerosol direct radiative: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ON CCN CONCENTRATION AND AEROSOL FIRST INDIRECT RADIATIVE composition, aerosol size distribution is the more dominant parameter on CCN activation Feingold, GRL 2003;...

  15. aerosol biokinetics concentrations: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ON CCN CONCENTRATION AND AEROSOL FIRST INDIRECT RADIATIVE composition, aerosol size distribution is the more dominant parameter on CCN activation Feingold, GRL 2003;...

  16. aerosol particle analysis: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Summary: data analysis algorithm is presented. Our earlier algorithm assumed a monomodal aerosol size distribution, while the new algorithm allows us to partition the aerosol...

  17. aerosol radiative forcing: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ON CCN CONCENTRATION AND AEROSOL FIRST INDIRECT RADIATIVE composition, aerosol size distribution is the more dominant parameter on CCN activation Feingold, GRL 2003;...

  18. aerosol research study: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in atmospheric thermal structure, burning, bio-sources changes? 12;Aerosol microphysics: size distribution, mixing state, morphology, shape 9 Aerosol Science and Technology,...

  19. aerosol chemical composition: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ON CCN CONCENTRATION AND AEROSOL FIRST INDIRECT RADIATIVE composition, aerosol size distribution is the more dominant parameter on CCN activation Feingold, GRL 2003;...

  20. Ice-condenser aerosol tests

    SciTech Connect (OSTI)

    Ligotke, M.W.; Eschbach, E.J.; Winegardner, W.K. (Pacific Northwest Lab., Richland, WA (United States))

    1991-09-01T23:59:59.000Z

    This report presents the results of an experimental investigation of aerosol particle transport and capture using a full-scale height and reduced-scale cross section test facility based on the design of the ice compartment of a pressurized water reactor (PWR) ice-condenser containment system. Results of 38 tests included thermal-hydraulic as well as aerosol particle data. Particle retention in the test section was greatly influenced by thermal-hydraulic and aerosol test parameters. Test-average decontamination factor (DF) ranged between 1.0 and 36 (retentions between {approximately}0 and 97.2%). The measured test-average particle retentions for tests without and with ice and steam ranged between DF = 1.0 and 2.2 and DF = 2.4 and 36, respectively. In order to apparent importance, parameters that caused particle retention in the test section in the presence of ice were steam mole fraction (SMF), noncondensible gas flow rate (residence time), particle solubility, and inlet particle size. Ice-basket section noncondensible flows greater than 0.1 m{sup 3}/s resulted in stable thermal stratification whereas flows less than 0.1 m{sup 3}/s resulted in thermal behavior termed meandering with frequent temperature crossovers between flow channels. 10 refs., 66 figs., 16 tabs.

  1. Chemistry at the Dirac Point of Graphene

    E-Print Network [OSTI]

    Sarkar, Santanu

    2013-01-01T23:59:59.000Z

    Haddon, R. C. Covalent Chemistry for Graphene Electronics.P. K. ; Yang, J. X. The Chemistry of Graphene. J. Mater.R. C. Organometallic Chemistry of Extended Periodic ?-

  2. CMR: Chemistry and Metallurgy Research Facility

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    CMR: Chemistry and Metallurgy Research Facility CMR: Chemistry and Metallurgy Research Facility The Los Alamos National Laboratory (LANL) Chemistry and Metallurgy Research (CMR)...

  3. Assessing regional scale predictions of aerosols, marine stratocumulus, and their interactions during VOCALS-REx using WRF-Chem

    SciTech Connect (OSTI)

    Yang, Qing; Gustafson, William I.; Fast, Jerome D.; Wang, Hailong; Easter, Richard C.; Morrison, H.; Lee, Y.- N.; Chapman, Elaine G.; Spak, S. N.; Mena-Carrasco, M. A.

    2011-12-02T23:59:59.000Z

    In the recent chemistry version (v3.3) of the Weather Research and Forecasting (WRF-Chem) model, we have coupled the Morrison double-moment microphysics scheme with interactive aerosols so that full two-way aerosol-cloud interactions are included in simulations. We have used this new WRF-Chem functionality in a study focused on assessing predictions of aerosols, marine stratocumulus clouds, and their interactions over the Southeast Pacific using measurements from the VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) and satellite retrievals. This study also serves as a detailed analysis of our WRF-Chem simulations contributed to the VOCALS model Assessment (VOCA) project. The WRF-Chem 31-day (October 15-November 16, 2008) simulation with aerosol-cloud interactions (AERO hereafter) is also compared to a simulation (MET hereafter) with fixed cloud droplet number concentrations assumed by the default in Morrison microphysics scheme with no interactive aerosols. The well-predicted aerosol properties such as number, mass composition, and optical depth lead to significant improvements in many features of the predicted stratocumulus clouds: cloud optical properties and microphysical properties such as cloud top effective radius, cloud water path, and cloud optical thickness, and cloud macrostructure such as cloud depth and cloud base height. These improvements in addition to the aerosol direct and semi-direct effects, in turn, feed back to the prediction of boundary-layer characteristics and energy budgets. Particularly, inclusion of interactive aerosols in AERO strengths temperature and humidity gradients within capping inversion layer and lowers the MBL depth by 150 m from that of the MET simulation. Mean top-of-the-atmosphere outgoing shortwave fluxes, surface latent heat, and surface downwelling longwave fluxes are in better agreement with observations in AERO, compared to the MET simulation. Nevertheless, biases in some of the simulated meteorological quantities (e.g., MBL temperature and humidity over the remote ocean) and aerosol quantities (e.g., overestimations of supermicron sea salt mass) might affect simulated stratocumulus and energy fluxes over the SEP, and require further investigations. Although not perfect, the overall performance of the regional model in simulating mesoscale aerosol-cloud interactions is encouraging and suggests that the inclusion of spatially varying aerosol characteristics is important when simulating marine stratocumulus over the southeastern Pacific.

  4. Dynamic

    Office of Legacy Management (LM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOn AprilA group currentBradleyTableSelling7111AWell: Gas productionDynamic , and Static ,

  5. Chemistry | More Science | ORNL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWPSuccessAlamosCharacterization ofChemistry and TransportChemistry of

  6. Chemistry | ornl.gov

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced. C o w l i t z CPlasma of theChemistry OxideChemistry Soft Matter

  7. Characterization of aerosols produced by surgical procedures

    SciTech Connect (OSTI)

    Yeh, H.C.; Muggenburg, B.A.; Lundgren, D.L.; Guilmette, R.A.; Snipes, M.B.; Jones, R.K. [Inhalation Toxicology Research Institute, Albuquerque, NM (United States); Turner, R.S. [Lovelace Health Systems, Albuquerque, NM (United States)

    1994-07-01T23:59:59.000Z

    In many surgeries, especially orthopedic procedures, power tools such as saws and drills are used. These tools may produce aerosolized blood and other biological material from bone and soft tissues. Surgical lasers and electrocautery tools can also produce aerosols when tissues are vaporized and condensed. Studies have been reported in the literature concerning production of aerosols during surgery, and some of these aerosols may contain infectious material. Garden et al. (1988) reported the presence of papilloma virus DNA in the fumes produced from laser surgery, but the infectivity of the aerosol was not assessed. Moon and Nininger (1989) measured the size distribution and production rate of emissions from laser surgery and found that particles were generally less than 0.5 {mu}m diameter. More recently there has been concern expressed over the production of aerosolized blood during surgical procedures that require power tools. In an in vitro study, the production of an aerosol containing the human immunodeficiency virus (HIV) was reported when power tools were used to cut tissues with blood infected with HIV. Another study measured the size distribution of blood aerosols produced by surgical power tools and found blood-containing particles in a number of size ranges. Health care workers are anxious and concerned about whether surgically produced aerosols are inspirable and can contain viable pathogens such as HIV. Other pathogens such as hepatitis B virus (HBV) are also of concern. The Occupational Safety and Health funded a project at the National Institute for Inhalation Toxicology Research Institute to assess the extent of aerosolization of blood and other tissues during surgical procedures. This document reports details of the experimental and sampling approach, methods, analyses, and results on potential production of blood-associated aerosols from surgical procedures in the laboratory and in the hospital surgical suite.

  8. The role of size-dependent dry deposition of sulfate aerosol in a three-dimensional Eulerian air quality model

    SciTech Connect (OSTI)

    Binkowski, F.S. [NOAA, Research Triangle Park, NC (United States); Shankar, U. [MCNC, Research Triangle Park, NC (United States)

    1994-12-31T23:59:59.000Z

    The Regional Particulate Model, a three-dimensional Eulerian air quality model, was developed to investigate aerosol particle issues of important to the US EPA and to meet the demands of the Clean Air Act amendments of 1990. In addition to aerosol dynamics such as growth and coagulation, the model includes photochemistry, transport, and deposition. A new formulation of dry deposition as a function of the aerosol size distribution has been incorporated into the model. This formulation allows for the representation of dry deposition of total particle number and total particle mass by deposition velocities specifically formulated for these two quantities as a function of particle size. Results for the dry deposition of sulfate mass from the new model will be compared with those from the Tagged Species Engineering Model for a variety of local conditions. The behavior of the aerosol size distribution responding to the new formulation will also be discussed.

  9. Aerosol Condensational Growth in Cloud Formation

    E-Print Network [OSTI]

    Geng, Jun

    2010-10-12T23:59:59.000Z

    A code for the quasi-stationary solution of the coupled heat and mass transport equations for aerosols in a finite volume was developed. Both mass and heat are conserved effectively in the volume, which results in a competitive aerosol condensation...

  10. 6, 32653319, 2006 Study aerosol with

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ACPD 6, 3265­3319, 2006 Study aerosol with two emission inventories and time factors A. de Meij et in Europe to two different emission inventories and temporal distribution of emissions A. de Meij 1 , M Study aerosol with two emission inventories and time factors A. de Meij et al. Title Page Abstract

  11. 5, 75777611, 2005 A look at aerosol

    E-Print Network [OSTI]

    Boyer, Edmond

    ACPD 5, 7577­7611, 2005 A look at aerosol formation using data mining techniques S. Hyv and Physics Discussions A look at aerosol formation using data mining techniques S. Hyv¨onen1 , H. Junninen2 Korkeakoski, Finland 4 Department of Forest Ecology, Faculty of Agriculture and Forestry, P.O. Box 27, FIN

  12. 2, 12871315, 2002 Aerosol sources and

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    in climate variability and climate change studies (IPCC, 2001). Radiative forcing of natural and their contribution to the chemical composition of aerosols in the Eastern Mediterranean Sea during summertime J aerosol sources in the Eastern Mediterranean5 Basin could be investigated at this location since the site

  13. 6, 1217912197, 2006 Aerosol formation in

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    troposphere and lower stratosphere. The model implements a first order scheme for resolving the aerosol size distribution within its geometric size10 sections, which efficiently suppresses numerical diffusion. We operate removes freshly nucleated particles by coagulation. The observation of high ultrafine aerosol

  14. Recovery Boiler Corrosion Chemistry

    E-Print Network [OSTI]

    Das, Suman

    11/13/2014 1 Recovery Boiler Corrosion Chemistry Sandy Sharp and Honghi Tran Symposium on Corrosion of a recovery boiler each cause their own forms of corrosion and cracking Understanding the origin of the corrosive conditions enables us to operate a boiler so as to minimize corrosion and cracking select

  15. Chemistry Portfolio (Revised August, 2011)

    E-Print Network [OSTI]

    Baltisberger, Jay H.

    at or above the 75th percentile on the American Chemical Society (ACS) Introductory Chemistry Exami- nation

  16. MAC 560 --Tropospheric Chemistry I Spring, 2009

    E-Print Network [OSTI]

    Miami, University of

    chemistry · to learn the atmospheric chemistry behind well-known phenomena such as smog, acid rain.3. Sulfur chemistry and acid rain 5.4. Nitrogen chemistry 5.5. Organic acids 5.6. Ecological and structural

  17. Impact of Aerosols on Tropical Cyclones: An Investigation Using Convection-permitting Model Simulation

    SciTech Connect (OSTI)

    Hazra, Anupam; Mukhopadhyay, P.; Taraphdar, Sourav; Chen, J. P.; Cotton, William R.

    2013-07-16T23:59:59.000Z

    The role of aerosols effect on two tropical cyclones over Bay of Bengal are investigated using a convection permitting model with two-moment mixed-phase bulk cloud microphysics scheme. The simulation results show the role of aerosol on the microphysical and dynamical properties of cloud and bring out the change in efficiency of the clouds in producing precipitation. The tracks of the TCs are hardly affected by the changing aerosol types, but the intensity exhibits significant sensitivity due to the change in aerosol contribution. It is also clearly seen from the analyses that higher heating in the middle troposphere within the cyclone center is in response to latent heat release as a consequence of greater graupel formation. Greater heating in the middle level is particularly noticeable for the clean aerosol regime which causes enhanced divergence in the upper level which, in turn, forces the lower level convergence. As a result, the cleaner aerosol perturbation is more unstable within the cyclone core and produces a more intense cyclone as compared to other two perturbations of aerosol. All these studies show the robustness of the concept of TC weakening by storm ingestion of high concentrations of CCN. The consistency of these model results gives us confidence in stating there is a high probability that ingestion of high CCN concentrations in a TC will lead to weakening of the storm but has little impact on storm direction. Moreover, as pollution is increasing over the Indian sub-continent, this study suggests pollution may be weakening TCs over the Bay of Bengal.

  18. Chemistry Department Colloquium: Spring, 2012

    E-Print Network [OSTI]

    Sheridan, Jennifer

    Chemistry Department Colloquium: Spring, 2012 Friday, March 16; 3:30 Seminar Hall (room 1315 Chemistry) Lost in Translation: How Regulators Use Science and How Scientists Can Help Bridge Gaps Stephanie to combine her Chemistry background with a legal education to improve the use of science in environmental

  19. A General Systems Theory for Atmospheric Flows and Atmospheric Aerosol Size Distribution

    E-Print Network [OSTI]

    A. M. Selvam

    2011-07-25T23:59:59.000Z

    Atmospheric flows exhibit selfsimilar fractal spacetime fluctuations manifested as the fractal geometry to global cloud cover pattern and inverse power law form for power spectra of meteorological parameters such as windspeed, temperature, rainfall etc. Inverse power law form for power spectra indicate long-range spacetime correlations or non-local connections and is a signature of selforganised criticality generic to dynamical systems in nature such as river flows, population dynamics, heart beat patterns etc. The author has developed a general systems theory which predicts the observed selforganised criticality as a signature of quantumlike chaos in dynamical systems. The model predictions are (i) The fractal fluctuations can be resolved into an overall logarithmic spiral trajectory with the quasiperiodic Penrose tiling pattern for the internal structure. (ii) The probability distribution represents the power (variance) spectrum for fractal fluctuations and follows universal inverse power law form incorporating the golden mean. Such a result that the additive amplitudes of eddies when squared represent probability distribution is observed in the subatomic dynamics of quantum systems such as the electron or photon. Therefore the irregular or unpredictable fractal fluctuations exhibit quantumlike chaos. (iii) Atmospheric aerosols are held in suspension by the vertical velocity distribution (spectrum). The atmospheric aerosol size spectrum is derived in terms of the universal inverse power law characterizing atmospheric eddy energy spectrum. Model predicted spectrum is in agreement with the following two experimentally determined atmospheric aerosol data sets, (i) SAFARI 2000 CV-580 Aerosol Data, Dry Season 2000 (CARG) (ii) World Data Centre Aerosols data sets for the three stations Ny {\\AA}lesund, Pallas and Hohenpeissenberg.

  20. ARM - AOS Aerosol Properties Plots

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearchSOLICITATIONIMODI FICATION OF CONTRACTOperations AMF2ViewersAOS Aerosol

  1. Aerosol Releases from the ICPP July 2005 FINAL REPORT

    E-Print Network [OSTI]

    Aerosol Releases from the ICPP July 2005 FINAL REPORT AEROSOL RELEASES FROM THE IDAHO CHEMICAL, Inc. July 2005 #12;Aerosol Releases from the ICPP July 2005 TABLE OF CONTENTS 1.0 Introduction ......................................... 5-1 5.1 Beta-minus Iodine Aerosol Formation Mechanism

  2. Exploring matrix effects on photochemistry of organic aerosols

    E-Print Network [OSTI]

    Nizkorodov, Sergey

    Exploring matrix effects on photochemistry of organic aerosols Hanna Lignella,b,1 , Mallory L of photochemical processes in organic aerosols will depend on both relative humidity and temperature and thus and impacts. aerosol aging | particle viscosity | organic photochemistry Aqueous droplets and aerosol

  3. Effects of Aerosols on Autumn Precipitation over Mid-Eastern China

    SciTech Connect (OSTI)

    Chen, Siyu; Huang, J.; Qian, Yun; Ge, Jinming; Su, Jing

    2014-09-20T23:59:59.000Z

    Long-term observational data indicated a decreasing trend for the amount of autumn precipitation (i.e. 54.3 mm per decade) over Mid-Eastern China, especially after 1980s (~ 5.6% per decade). To examine the cause of the decreasing trend, the mechanisms associated with the change of autumn precipitation were investigated from the perspective of water vapor transportation, atmospheric stability and cloud microphysics. Results show that the decrease of convective available potential energy (i.e. 12.81 J kg-1/ decade) and change of cloud microphysics, which were closely related to the increase of aerosol loading during the past twenty years, were the two primary factors responsible for the decrease of autumn precipitation. Ours results showed that increased aerosol could enhance the atmospheric stability thus weaken the convection. Meanwhile, more aerosols also led to a significant decline of raindrop concentration and to a delay of raindrop formation because of smaller size of cloud droplets. Thus, increased aerosols produced by air pollution could be one of the major reasons for the decrease of autumn precipitation. Furthermore, we found that the aerosol effects on precipitation in autumn was more significant than in other seasons, partly due to the relatively more stable synoptic system in autumn. The impact of large-scale circulation dominated in autumn and the dynamic influence on precipitation was more important than the thermodynamic activity.

  4. Long-range forces and the collisions of free-molecular and transition regime aerosols

    SciTech Connect (OSTI)

    Marlow, W.H.

    1988-12-31T23:59:59.000Z

    An aerosol here is understood to be a two-component system comprised of gaseous and condensed phases with the characteristic that the condensed phase is not an equilibrium subsystem. In contrast to the usual definitions based upon geometrical or mechanical variables, this quasi-thermodynamic formulation is framed to emphasize the dynamical behavior of aerosols by allowing for coagulation and other aerosol evolutionary processes as natural consequences of the interactions and state variables appropriate to the system. As will become clear later, it also provides a point of departure for distinguishing aerosol particles from unstable gas-phase cluster systems. The question of accommodation in particle collisions must be addressed as a prelude to the discussion of the role of long-range forces. Microscopic reversibility is frequently assumed for molecular collisions with either molecules or solid surfaces. In the case of aerosol collisions, the implication of this assumption is that collisions are elastic, which is contrary to the evidence from coagulation experiments and the conventional operational assumption of sticking upon collision. Gay and Berne have performed computer simulations of the collision of two clusters consisting of a total of 135 molecules interacting via Lennard-Jones potentials. That work showed that complete accommodation, accompanied by overall heating of the unified cluster, occurred. Since heating represents an irreversible degradation of the kinetic energy of the collision, the hamiltonian of the two-cluster system should be considered as dissipative and therefore microscopic reversibility does not apply.

  5. Global impact of smoke aerosols from landscape fires on climate and the Hadley circulation

    E-Print Network [OSTI]

    Tosca, M. G; Randerson, J. T; Zender, C. S

    2013-01-01T23:59:59.000Z

    of biomass burn- ing aerosol on the monsoon circulationA. , and Rudich, Y. : Aerosol invigoration and restructuring2011. Albrecht, B. A. : Aerosols, cloud microphysics, and

  6. Characterization of the Molecular Composition of Secondary Organic Aerosols using High Resolution Mass Spectrometry

    E-Print Network [OSTI]

    Sellon, Rachel Elizabeth

    2012-01-01T23:59:59.000Z

    in secondary organic aerosol formation from isoprene, Proc.biogenic secondary organic aerosol, J. Phys. Chem. A, 112(in secondary organic aerosol, Environ. Sci. Technol. , 41(

  7. Chapter 3: Evaluating the impacts of carbonaceous aerosols on clouds and climate

    E-Print Network [OSTI]

    Menon, Surabi

    2008-01-01T23:59:59.000Z

    Cloud susceptibility and the first aerosol indirect forcing:Sensitivity to BC and aerosol concentrations. J. Geophys.of cloud droplet and aerosols number concentrations:

  8. Correlations between Optical, Chemical and Physical Properties of Biomass Burn Aerosols

    E-Print Network [OSTI]

    2008-01-01T23:59:59.000Z

    instruments and photoelectric aerosol sensors in source-sampling of black carbon aerosol and particle-bound PAHsAirborne minerals and related aerosol particles: Effects on

  9. Composition, sources, and formation of secondary organic aerosols from urban emissions

    E-Print Network [OSTI]

    Liu, Shang; Liu, Shang

    2012-01-01T23:59:59.000Z

    organonitrate functional groups in aerosol particles200 5.1v aerosol Chapter 3 Meteorological conditions during theSecondary organic aerosol formation from fossil fuel sources

  10. Particles, Aerosols, and Their Transport in Built Environment Particles, aerosols, or collectively called particulate matters (PM) are ubiquitous indoor

    E-Print Network [OSTI]

    Chen, Qingyan "Yan"

    1 Editorial Particles, Aerosols, and Their Transport in Built Environment Particles, aerosols or aerosols and their transport in built environment. The first five papers in this special issue addressed influences ozone removal and the secondary organic aerosols generation. The study from Zuraimi et al

  11. Sources and Formation of OrganicSources and Formation of Organic Aerosols in our AtmosphereAerosols in our Atmosphere

    E-Print Network [OSTI]

    Einat, Aharonov

    Sources and Formation of OrganicSources and Formation of Organic Aerosols in our AtmosphereAerosols Department of Chemical Engineering University of Patras, Greece #12;Sources of Organic AerosolSources of Organic Aerosol Primary Secondary Anthropogenic ·Gasoline ·Diesel ·Biomass burning ·Meat Cooking Biogenic

  12. Studying trends in biomass burning aerosol using the Absorbing Aerosol Index derived from GOME, SCIAMACHY, and GOME-2

    E-Print Network [OSTI]

    Tilstra, Gijsbert

    Studying trends in biomass burning aerosol using the Absorbing Aerosol Index derived from GOME the resulting time series, we use tropospheric NO2 data as a reference in the regions dominated by biomass sensitive to desert dust aerosols (DDA) and biomass burning aerosols (BBA). See Figure 1. The AAI

  13. CARES: Carbonaceous Aerosol and Radiative Effects Study Science Plan

    SciTech Connect (OSTI)

    Zaveri, RA; Shaw, WJ; Cziczo, DJ

    2010-05-27T23:59:59.000Z

    Carbonaceous aerosol components, which include black carbon (BC), urban primary organic aerosols (POA), biomass burning aerosols, and secondary organic aerosols (SOA) from both urban and biogenic precursors, have been previously shown to play a major role in the direct and indirect radiative forcing of climate. The primary objective of the CARES 2010 intensive field study is to investigate the evolution of carbonaceous aerosols of different types and their effects on optical and cloud formation properties.

  14. The behavior of constant rate aerosol reactors

    SciTech Connect (OSTI)

    Friedlander, S.K.

    1982-01-01T23:59:59.000Z

    An aerosol reactor is a gaseous system in which fine particles are formed by chemical reaction in either a batch or flow process. The particle sizes of interest range from less than 10 angstrom (molecular clusters) to 10 ..mu..m. Such reactors may be operated to study the aerosol formation process, as in a smog reactor, or to generate a product such as a pigment or a catalytic aerosol. Aerosol reactors can be characterized by three temporal or spatial zones or regions of operation for batch and flow reactors, respectively. In zone I, chemical reaction results in the formation of condensable molecular products which nucleate and form very high concentrations of small particles. The number density depends on the concentration of preexisting aerosol. Zone II is a transition region in which the aerosol number concentration levels off as a result of hetergeneous condensation by the stable aerosol. In zone III coagulation becomes sufficiently rapid to reduce the particle number concentration. There may be a zone IV in which agglomerates form.

  15. Capstone Depleted Uranium Aerosols: Generation and Characterization

    SciTech Connect (OSTI)

    Parkhurst, MaryAnn; Szrom, Fran; Guilmette, Ray; Holmes, Tom; Cheng, Yung-Sung; Kenoyer, Judson L.; Collins, John W.; Sanderson, T. Ellory; Fliszar, Richard W.; Gold, Kenneth; Beckman, John C.; Long, Julie

    2004-10-19T23:59:59.000Z

    In a study designed to provide an improved scientific basis for assessing possible health effects from inhaling depleted uranium (DU) aerosols, a series of DU penetrators was fired at an Abrams tank and a Bradley fighting vehicle. A robust sampling system was designed to collect aerosols in this difficult environment and continuously monitor the sampler flow rates. Aerosols collected were analyzed for uranium concentration and particle size distribution as a function of time. They were also analyzed for uranium oxide phases, particle morphology, and dissolution in vitro. The resulting data provide input useful in human health risk assessments.

  16. A shrouded probe aerosol sampling cyclone

    E-Print Network [OSTI]

    Little, Stewart Craig

    1992-01-01T23:59:59.000Z

    AED at three different flow rates. The results would then be interpolated to give the needed flow rate value. The collection efficiency of the cyclone was characterized by the approach of generating liquid aerosols containing an analytical tracer... was neutralized by passing the aerosol flow through a chamber which contained a 10 mCi krypton 85 line source. Aerosol size produced by this apparatus depends on the concentration of the non-volatile solute, the size of the orifice, and the frequency applied...

  17. Evaluating Global Aerosol Models and Aerosol and Water Vapor Properties Near Clouds

    SciTech Connect (OSTI)

    Richard A. Ferrare; David D. Turner

    2011-09-01T23:59:59.000Z

    Project goals: (1) Use the routine surface and airborne measurements at the ARM SGP site, and the routine surface measurements at the NSA site, to continue our evaluations of model aerosol simulations; (2) Determine the degree to which the Raman lidar measurements of water vapor and aerosol scattering and extinction can be used to remotely characterize the aerosol humidification factor; (3) Use the high temporal resolution CARL data to examine how aerosol properties vary near clouds; and (4) Use the high temporal resolution CARL and Atmospheric Emitted Radiance Interferometer (AERI) data to quantify entrainment in optically thin continental cumulus clouds.

  18. Aerosol Best Estimate Value-Added Product

    SciTech Connect (OSTI)

    Flynn, C; Turner, D; Koontz, A; Chand, D; Sivaraman, C

    2012-07-19T23:59:59.000Z

    The objective of the Aerosol Best Estimate (AEROSOLBE) value-added product (VAP) is to provide vertical profiles of aerosol extinction, single scatter albedo, asymmetry parameter, and Angstroem exponents for the atmospheric column above the Central Facility at the ARM Southern Great Plains (SGP) site. We expect that AEROSOLBE will provide nearly continuous estimates of aerosol optical properties under a range of conditions (clear, broken clouds, overcast clouds, etc.). The primary requirement of this VAP was to provide an aerosol data set as continuous as possible in both time and height for the Broadband Heating Rate Profile (BBHRP) VAP in order to provide a structure for the comprehensive assessment of our ability to model atmospheric radiative transfer for all conditions. Even though BBHRP has been completed, AEROSOLBE results are very valuable for environmental, atmospheric, and climate research.

  19. 5, 90399063, 2005 Arctic aerosol effect

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Radiation Measurement (ARM) data, we find surface cloud radiative forcing (SCRF) is -22 W/m 2 for shortwave. If aerosols are taken into account, the SCRF has been increased during winter while15 negative SCRF has been

  20. Indirect and Semi-Direct Aerosol Campaign: The Impact of Arctic...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Indirect and Semi-Direct Aerosol Campaign: The Impact of Arctic Aerosols on Clouds . Indirect and Semi-Direct Aerosol Campaign: The Impact of Arctic Aerosols on Clouds . Abstract:...

  1. Aerosol remote sensing in polar regions

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tomasi, C.; Wagener, R.; Kokhanovsky, A. A.; Lupi, A.; Ritter, C.; Smirnov, A.; O Neill, N. T.; Stone, R. S.; Holben, B. N.; Nyeki, S.; Wehrli, C.; Stohl, A.; Mazzola, M.; Lanconelli, C.; Vitale, V.; Stebel, K.; Aaltonen, V.; de Leeuw, G.; Rodriguez, E.; Herber, A. B.; Radionov, V. F.; Zielinski, T.; Petelski, T.; Sakerin, S. M.; Kabanov, D. M.; Xue, Y.; Mei, L.; Istomina, L.; Wagener, R.; McArthur, B.; Sobolewski, P. S.; Kivi, R.; Courcoux, Y.; Larouche, P.; Broccardo, S.; Piketh, S. J.

    2015-01-01T23:59:59.000Z

    Multi-year sets of ground-based sun-photometer measurements conducted at 12 Arctic sites and 9 Antarctic sites were examined to determine daily mean values of aerosol optical thickness ?(?) at visible and near-infrared wavelengths, from which best-fit values of Ĺngström's exponent ? were calculated. Analysing these data, the monthly mean values of ?(0.50 ?m) and ? and the relative frequency histograms of the daily mean values of both parameters were determined for winter–spring and summer–autumn in the Arctic and for austral summer in Antarctica. The Arctic and Antarctic covariance plots of the seasonal median values of ? versus ?(0.50 ?m) showed: (i) a considerable increase in ?(0.50 ?m) for the Arctic aerosol from summer to winter–spring, without marked changes in ?; and (ii) a marked increase in ?(0.50 ?m) passing from the Antarctic Plateau to coastal sites, whereas ? decreased considerably due to the larger fraction of sea-salt aerosol. Good agreement was found when comparing ground-based sun-photometer measurements of ?(?) and ? at Arctic and Antarctic coastal sites with Microtops measurements conducted during numerous AERONET/MAN cruises from 2006 to 2013 in three Arctic Ocean sectors and in coastal and off-shore regions of the Southern Atlantic, Pacific, and Indian Oceans, and the Antarctic Peninsula. Lidar measurements were also examined to characterise vertical profiles of the aerosol backscattering coefficient measured throughout the year at Ny-Ĺlesund. Satellite-based MODIS, MISR, and AATSR retrievals of ?(?) over large parts of the oceanic polar regions during spring and summer were in close agreement with ship-borne and coastal ground-based sun-photometer measurements. An overview of the chemical composition of mode particles is also presented, based on in-situ measurements at Arctic and Antarctic sites. Fourteen log-normal aerosol number size-distributions were defined to represent the average features of nuclei, accumulation and coarse mode particles for Arctic haze, summer background aerosol, Asian dust and boreal forest fire smoke, and for various background austral summer aerosol types at coastal and high-altitude Antarctic sites. The main columnar aerosol optical characteristics were determined for all 14 particle modes, based on in-situ measurements of the scattering and absorption coefficients. Diurnally averaged direct aerosol-induced radiative forcing and efficiency were calculated for a set of multimodal aerosol extinction models, using various Bidirectional Reflectance Distribution Function models over vegetation-covered, oceanic and snow-covered surfaces. These gave a reliable measure of the pronounced effects of aerosols on the radiation balance of the surface–atmosphere system over polar regions.

  2. Aerosol remote sensing in polar regions

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tomasi, C.; Wagener, R.; Kokhanovsky, A. A.; Lupi, A.; Ritter, C.; Smirnov, A.; O Neill, N. T.; Stone, R. S.; Holben, B. N.; Nyeki, S.; et al

    2015-01-01T23:59:59.000Z

    Multi-year sets of ground-based sun-photometer measurements conducted at 12 Arctic sites and 9 Antarctic sites were examined to determine daily mean values of aerosol optical thickness ?(?) at visible and near-infrared wavelengths, from which best-fit values of Ĺngström's exponent ? were calculated. Analysing these data, the monthly mean values of ?(0.50 ?m) and ? and the relative frequency histograms of the daily mean values of both parameters were determined for winter–spring and summer–autumn in the Arctic and for austral summer in Antarctica. The Arctic and Antarctic covariance plots of the seasonal median values of ? versus ?(0.50 ?m) showed: (i)more »a considerable increase in ?(0.50 ?m) for the Arctic aerosol from summer to winter–spring, without marked changes in ?; and (ii) a marked increase in ?(0.50 ?m) passing from the Antarctic Plateau to coastal sites, whereas ? decreased considerably due to the larger fraction of sea-salt aerosol. Good agreement was found when comparing ground-based sun-photometer measurements of ?(?) and ? at Arctic and Antarctic coastal sites with Microtops measurements conducted during numerous AERONET/MAN cruises from 2006 to 2013 in three Arctic Ocean sectors and in coastal and off-shore regions of the Southern Atlantic, Pacific, and Indian Oceans, and the Antarctic Peninsula. Lidar measurements were also examined to characterise vertical profiles of the aerosol backscattering coefficient measured throughout the year at Ny-Ĺlesund. Satellite-based MODIS, MISR, and AATSR retrievals of ?(?) over large parts of the oceanic polar regions during spring and summer were in close agreement with ship-borne and coastal ground-based sun-photometer measurements. An overview of the chemical composition of mode particles is also presented, based on in-situ measurements at Arctic and Antarctic sites. Fourteen log-normal aerosol number size-distributions were defined to represent the average features of nuclei, accumulation and coarse mode particles for Arctic haze, summer background aerosol, Asian dust and boreal forest fire smoke, and for various background austral summer aerosol types at coastal and high-altitude Antarctic sites. The main columnar aerosol optical characteristics were determined for all 14 particle modes, based on in-situ measurements of the scattering and absorption coefficients. Diurnally averaged direct aerosol-induced radiative forcing and efficiency were calculated for a set of multimodal aerosol extinction models, using various Bidirectional Reflectance Distribution Function models over vegetation-covered, oceanic and snow-covered surfaces. These gave a reliable measure of the pronounced effects of aerosols on the radiation balance of the surface–atmosphere system over polar regions.« less

  3. Electrically Driven Technologies for Radioactive Aerosol Abatement

    SciTech Connect (OSTI)

    David W. DePaoli; Ofodike A. Ezekoye; Costas Tsouris; Valmor F. de Almeida

    2003-01-28T23:59:59.000Z

    The purpose of this research project was to develop an improved understanding of how electriexecy driven processes, including electrocoalescence, acoustic agglomeration, and electric filtration, may be employed to efficiently treat problems caused by the formation of aerosols during DOE waste treatment operations. The production of aerosols during treatment and retrieval operations in radioactive waste tanks and during thermal treatment operations such as calcination presents a significant problem of cost, worker exposure, potential for release, and increased waste volume.

  4. Apparatus for sampling and characterizing aerosols

    DOE Patents [OSTI]

    Dunn, P.F.; Herceg, J.E.; Klocksieben, R.H.

    1984-04-11T23:59:59.000Z

    Apparatus for sampling and characterizing aerosols having a wide particle size range at relatively low velocities may comprise a chamber having an inlet and an outlet, the chamber including: a plurality of vertically stacked, successive particle collection stages; each collection stage includes a separator plate and a channel guide mounted transverse to the separator plate, defining a labyrinthine flow path across the collection stage. An opening in each separator plate provides a path for the aerosols from one collection stage t

  5. Aerosol fabrication methods for monodisperse nanoparticles

    DOE Patents [OSTI]

    Jiang, Xingmao; Brinker, C Jeffrey

    2014-10-21T23:59:59.000Z

    Exemplary embodiments provide materials and methods for forming monodisperse particles. In one embodiment, the monodisperse particles can be formed by first spraying a nanoparticle-containing dispersion into aerosol droplets and then heating the aerosol droplets in the presence of a shell precursor to form core-shell particles. By removing either the shell layer or the nanoparticle core of the core-shell particles, monodisperse nanoparticles can be formed.

  6. Development of plutonium aerosol fractionation system 

    E-Print Network [OSTI]

    Mekala, Malla R.

    1993-01-01T23:59:59.000Z

    DEVELOPMENT OF A PLUTONIUM AEROSOL FRACTIONATION SYSTEM A Thesis by MALLA R. MEKALA Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August... 1993 Major Subject: Mechanical Engineering DEVELOPMENT OP A PLUTONIUM AEROSOL FRACTIONATION SYSTEM A Thesis by MALLA R. MEKALA Approved as to style and content by: A. R. McFarland (Chair of Committee) N. K. Anand (Mer toer) (', & C. B...

  7. Development of plutonium aerosol fractionation system

    E-Print Network [OSTI]

    Mekala, Malla R.

    1993-01-01T23:59:59.000Z

    microns), inhalation accidents occurring during maintenance operations can be expected to result in long term retention of 20% to 30% of the inhaled aerosol. Thind"' performed experiments over a span of one year to observe the consistency...DEVELOPMENT OF A PLUTONIUM AEROSOL FRACTIONATION SYSTEM A Thesis by MALLA R. MEKALA Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August...

  8. WRF-Chem Simulations of Aerosols and Anthropogenic Aerosol Radiative Forcing in East Asia

    SciTech Connect (OSTI)

    Gao, Yi; Zhao, Chun; Liu, Xiaohong; Zhang, Meigen; Leung, Lai-Yung R.

    2014-08-01T23:59:59.000Z

    This study aims to provide a first comprehensive evaluation of WRF-Chem for modeling aerosols and anthropogenic aerosol radiative forcing (RF) over East Asia. Several numerical experiments were conducted from November 2007 to December 2008. Comparison between model results and observations shows that the model can generally reproduce the observed spatial distributions of aerosol concentration, aerosol optical depth (AOD) and single scattering albedo (SSA) from measurements at different sites, including the relatively higher aerosol concentration and AOD over East China and the relatively lower AOD over Southeast Asia, Korean, and Japan. The model also depicts the seasonal variation and transport of pollutions over East Asia. Particulate matter of 10 um or less in the aerodynamic diameter (PM10), black carbon (BC), sulfate (SO42-), nitrate (NO3-) and ammonium (NH4+) concentrations are higher in spring than other seasons in Japan due to the pollutant transport from polluted area of East Asia. AOD is high over Southwest and Central China in winter, spring and autumn and over North China in summer while is low over South China in summer due to monsoon precipitation. SSA is lowest in winter and highest in summer. The model also captures the dust events at the Zhangye site in the semi-arid region of China. Anthropogenic aerosol RF is estimated to range from -5 to -20 W m-2 over land and -20 to -40 W m-2 over ocean at the top of atmosphere (TOA), 5 to 30 W m-2 in the atmosphere (ATM) and -15 to -40 W m-2 at the bottom (BOT). The warming effect of anthropogenic aerosol in ATM results from BC aerosol while the negative aerosol RF at TOA is caused by scattering aerosols such as SO4 2-, NO3 - and NH4+. Positive BC RF at TOA compensates 40~50% of the TOA cooling associated with anthropogenic aerosol.

  9. Sandia National Laboratories: atmospheric chemistry

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and atmospheric chemistry that is expected to benefit auto and engine manufacturers, oil and gas utilities, and other industries that employ combustion models. A paper...

  10. Sandia National Laboratories: combustion chemistry

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and atmospheric chemistry that is expected to benefit auto and engine manufacturers, oil and gas utilities, and other industries that employ combustion models. A paper...

  11. aerosol properties in-canopy: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    aerosol, cloud condensation nuclei, water accommodation coefficient, organic of aerosol size distribution, chemical composition and cloud condensation nuclei (CCN) concentration...

  12. agricultural chemistry: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of Chemistry Honors in Chemistry Research Instructions (Seniors only) Materials Science Websites Summary: Department of Chemistry Honors in Chemistry Research Instructions...

  13. Photodissociation Dynamics Laurie J. Butler*

    E-Print Network [OSTI]

    Butler, Laurie J.

    Photodissociation Dynamics Laurie J. Butler* Department of Chemistry, UniVersity of Chicago of photodissociation dynamics over the past 30 years are reviewed. An overview of experimental techniques that have of photodissociation dynamics has grown explo- sively in the past few decades. Spearheaded by developments in laser

  14. Environmental Soil Chemistry Second Edition Environmental Soil Chemistry illustrates fundamental principles of soil

    E-Print Network [OSTI]

    Sparks, Donald L.

    Environmental Soil Chemistry Second Edition Environmental Soil Chemistry illustrates fundamental principles of soil chemistry with respect to environmental reactions between soils and other natural contemporary training in the basics of soil chemistry and applications to real-world environmental concerns

  15. Chemistry Major and Minor At A Glance

    E-Print Network [OSTI]

    Schmitt, William R.

    Chemistry Major and Minor At A Glance Major I ­ Pre-professional (Medicine, Dentistry, Business, Law, Engineering) Major II ­ ACS Certified e.g. Graduate Study or Entry Level Chemistry Employment. Major III ­ Forensic Chemistry Major IV** ­ Biochemistry Option Chemistry Minor General Chemistry I & II

  16. Chemistry and Biochemistry Graduate Student Spring 2012

    E-Print Network [OSTI]

    Chemistry and Biochemistry Graduate Student Tutors Spring 2012 (All arrangements are solely between.axelrod@mail.utexas.edu Organic Chemistry Chris Bates chrismbates@gmail.com General Chemistry Lecture/Lab Organic Chemistry Amy Bonaparte abonaparte@mail.utexas.edu General and Organic Chemistry Shelly Casciato slcasciato

  17. Chemistry UMass Lowell Commonwealth Honors Track

    E-Print Network [OSTI]

    Massachusetts at Lowell, University of

    Chemistry UMass Lowell Commonwealth Honors Track Scholarship Rises. Freshman Year/ Fall Semester Cr) Honors Chemistry I 3 84.136 (H) Honors Chemistry II 3 84.123 (H) Honors Chemistry I Lab 1 84.124 (H) Honors Chemistry II Lab 1 92.131 Calculus I 4 92.132 Honors Calculus II 4 Hon 110 Honors FYSH (AH) 3 Gen

  18. Chemistry and Biochemistry Graduate Student Summer 2012

    E-Print Network [OSTI]

    Chemistry and Biochemistry Graduate Student Tutors Summer 2012 (All arrangements are solely between.axelrod@mail.utexas.edu Organic Chemistry Chris Bates chrismbates@gmail.com General Chemistry Lecture/Lab Organic Chemistry Amy Bonaparte abonaparte@mail.utexas.edu General and Organic Chemistry Shelly Casciato slcasciato

  19. Evaluating Global Aerosol Models and Aerosol and Water Vapor Properties Near Clouds

    SciTech Connect (OSTI)

    Turner, David, D.; Ferrare, Richard, A.

    2011-07-06T23:59:59.000Z

    The 'Evaluating Global Aerosol Models and Aerosol and Water Vapor Properties Near Clouds' project focused extensively on the analysis and utilization of water vapor and aerosol profiles derived from the ARM Raman lidar at the Southern Great Plains ARM site. A wide range of different tasks were performed during this project, all of which improved quality of the data products derived from the lidar or advanced the understanding of atmospheric processes over the site. These activities included: upgrading the Raman lidar to improve its sensitivity; participating in field experiments to validate the lidar aerosol and water vapor retrievals; using the lidar aerosol profiles to evaluate the accuracy of the vertical distribution of aerosols in global aerosol model simulations; examining the correlation between relative humidity and aerosol extinction, and how these change, due to horizontal distance away from cumulus clouds; inferring boundary layer turbulence structure in convective boundary layers from the high-time-resolution lidar water vapor measurements; retrieving cumulus entrainment rates in boundary layer cumulus clouds; and participating in a field experiment that provided data to help validate both the entrainment rate retrievals and the turbulent profiles derived from lidar observations.

  20. Aerosols in Central California: Unexpectedly Large Contribution of Coarse Mode to Aerosol Radiative Forcing

    SciTech Connect (OSTI)

    Kassianov, Evgueni I.; Pekour, Mikhail S.; Barnard, James C.

    2012-10-20T23:59:59.000Z

    The majority of previous studies dealing with effect of coarse-mode aerosols on the radiation budget have focused primary on polluted regions with substantial aerosol loadings. We reexamine this effect for a relatively "pristine" area using a unique 1-month dataset collected during recent Carbonaceous Aerosol and Radiative Effects Study (CARES). We demonstrate that the coarse-mode (supermicron) particles can contribute substantially (more than 50%) and frequently (up to 85% of time) to the total volume. In contrast to the conventional expectations that the radiative impact of coarse-mode aerosols should be small for "pristine" regions, we find that the neglecting of the large particles may lead to significant overestimation (up to 45%) of direct aerosol radiative forcing at the top-of atmosphere despite of very small aerosol optical depth (about 0.05 at 0.5 ). Our findings highlight the potential for widespread impacts of the coarse-mode aerosols on the pristine radiative properties over land and the need for more explicit inclusion of the coarse-mode aerosols in climate-related observational and model studies.

  1. AEROSOL CHEMICAL COMPOSITION CHARACTERIZATION AT THE ARM SOUTHERN GREAT PLAINS (SGP) SITE USING AN AEROSOL CHEMICAL

    E-Print Network [OSTI]

    AEROSOL CHEMICAL COMPOSITION CHARACTERIZATION AT THE ARM SOUTHERN GREAT PLAINS (SGP) SITE USING AN AEROSOL CHEMICAL SPECIATION MONITOR Yin-Nan Lee1 , Fan Mei1 , Stephanie DeJong1 , Anne Jefferson2 1 Atmospheric Sciences Division, Brookhaven National Lab, Upton, NY 2 CIRES, University of Colorado, Boulder, CO

  2. Direct and semidirect aerosol effects of southern African biomass burning aerosol

    E-Print Network [OSTI]

    Wood, Robert

    radiative effects associated with increased low cloud cover dominate over a weaker positive allsky direct 2011; published 21 June 2011. [1] Direct and semidirect radiative effects of biomass burning aerosols radiative effect (DRE). In contrast, over the land where the aerosols are often below or within cloud layers

  3. BA in CHEMISTRY (692827) MAP Sheet Department of Chemistry and Biochemistry

    E-Print Network [OSTI]

    Seamons, Kent E.

    BA in CHEMISTRY (692827) MAP Sheet Department of Chemistry and Biochemistry For students entering Chemistry and Biochemistry Department requires the final 10 hours of required chemistry credit to be taken for graduation. Complete the following: Chem 111* Honors Principles of Chemistry Chem 112 Principles of Chemistry

  4. Chemistry -Bachelor of Science (SCHUG) Total Credits Required: 128 Chemistry -ACS Certified

    E-Print Network [OSTI]

    Chemistry - Bachelor of Science (SCHUG) Total Credits Required: 128 Chemistry - ACS Certified Major of the following courses Course Credits Course Credits CH1150 University Chemistry I AND 3 CH4110 Pharmaceutical Chemistry: Drug Action 3 CH1151 University Chemistry Lab 1 AND 1 CH4120 Pharmaceutical Chemistry: Drug

  5. Chemistry -Bachelor of Science (SCH1UG) Total Credits Required: 128 Chemistry/Polymers -ACS Certified

    E-Print Network [OSTI]

    Chemistry - Bachelor of Science (SCH1UG) Total Credits Required: 128 Chemistry/Polymers - ACS credits Course Credits Course Credits CH1150 University Chemistry I AND 3 CH4610 Intro to Polymer Science 3 CH1151 University Chemistry Lab 1 AND 1 CH4620 Polymer Chemistry 3 CH1153 University Chemistry

  6. Model analysis of the anthropogenic aerosol effect on clouds over East Asia

    SciTech Connect (OSTI)

    Gao, Yi; Zhang, Meigen; Liu, Xiaohong; Zhao, Chun

    2012-01-16T23:59:59.000Z

    A coupled meteorology and aerosol/chemistry model WRF-Chem (Weather Research and Forecast model coupled with Chemistry) was used to conduct a pair of simulations with present-day (PD) and preindustrial (PI) emissions over East Asia to examine the aerosol indirect effect on clouds. As a result of an increase in aerosols in January, the cloud droplet number increased by 650 cm{sup -3} over the ocean and East China, 400 cm{sup -3} over Central and Southwest China, and less than 200 cm{sup -3} over North China. The cloud liquid water path (LWP) increased by 40-60 g m{sup -2} over the ocean and Southeast China and 30 g m{sup -2} over Central China; the LWP increased less than 5 g m{sup -2} or decreased by 5 g m{sup -2} over North China. The effective radius (Re) decreased by more than 4 {mu}m over Southwest, Central, and Southeast China and 2 {mu}m over North China. In July, variations in cloud properties were more uniform; the cloud droplet number increased by approximately 250-400 cm{sup -3}, the LWP increased by approximately 30-50 g m{sup -2}, and Re decreased by approximately 3 {mu}m over most regions of China. In response to cloud property changes from PI to PD, shortwave (SW) cloud radiative forcing strengthened by 30 W m{sup -2} over the ocean and 10 W m{sup -2} over Southeast China, and it weakened slightly by approximately 2-10 W m{sup -2} over Central and Southwest China in January. In July, SW cloud radiative forcing strengthened by 15 W m{sup -2} over Southeast and North China and weakened by 10 W m{sup -2} over Central China. The different responses of SW cloud radiative forcing in different regions was related to cloud feedbacks and natural variability.

  7. The Radiative Role of Free Tropospheric Aerosols and Marine Clouds over the Central North Atlantic

    SciTech Connect (OSTI)

    Mazzoleni, Claudio [Michigan Technological University; Kumar, Sumit [Michigan Technological University; Wright, Kendra [Michigan Technological University; Kramer, Louisa [Michigan Technological University; Mazzoleni, Lynn [Michigan Technological University; Owen, Robert [Michigan Technological University; Helmig, Detlev [University of Colorado at Boulder

    2014-12-09T23:59:59.000Z

    The scientific scope of the project was to exploit the unique location of the Pico Mountain Observatory (PMO) located in the summit caldera of the Pico Volcano in Pico Island in the Azores, for atmospheric studies. The observatory, located at 2225m a.s.l., typically samples free tropospheric aerosols laying above the marine low-level clouds and long-range transported from North America. The broad purpose of this research was to provide the scientific community with a better understanding of fundamental physical processes governing the effects of aerosols on radiative forcing and climate; with the ultimate goal of improving our abilities to understand past climate and to predict future changes through numerical models. The project was 'exploratory' in nature, with the plan to demonstrate the feasibility of deploying for the first time, an extensive aerosol research package at PMO. One of the primary activities was to test the deployment of these instruments at the site, to collect data during the 2012 summer season, and to further develop the infrastructure and the knowledge for performing novel research at PMO in follow-up longer-term aerosol-cloud studies. In the future, PMO could provide an elevated research outpost to support the renewed DOE effort in the Azores that was intensified in 2013 with the opening of the new sea-level ARM-DOE Eastern North Atlantic permanent facility at Graciosa Island. During the project period, extensive new data sets were collected for the planned 2012 season. Thanks to other synergistic activities and opportunities, data collection was then successfully extended to 2013 and 2014. Highlights of the scientific findings during this project include: a) biomass burning contribute significantly to the aerosol loading in the North Atlantic free troposphere; however, long-range transported black carbon concentrations decreased substantially in the last decade. b) Single black carbon particles – analyzed off-line at the electron microscope – were often very compacted, suggesting cloud processing and exhibiting different optical properties from fresh emissions. In addition, black carbon was found to be sometimes mixed with mineral dust, affecting its optical properties and potential forcing. c) Some aerosols collected at PMO acted as ice nuclei, potentially contributing to cirrus cloud formation during their transport in the upper free troposphere. Identified good ice nuclei were often mineral dust particles. d) The free tropospheric aerosols studied at PMO have relevance to low level marine clouds due, for example, to synoptic subsidence entraining free tropospheric aerosols into the marine boundary layer. This has potentially large consequences on cloud condensation nuclei concentrations and compositions in the marine boundary layer; therefore, having an effect on the marine stratus clouds, with potentially important repercussions on the radiative forcing. The scientific products of this project currently include contributions to two papers published in the Nature Publishing group (Nature Communications and Scientific Reports), one paper under revision for Atmospheric Chemistry and Physics, one in review in Geophysical Research Letters and one recently submitted to Atmospheric Chemistry and Physics Discussion. In addition, four manuscripts are in advanced state of preparation. Finally, twenty-eight presentations were given at international conferences, workshops and seminars.

  8. Course Syllabus: Chemistry 3AL Course Information

    E-Print Network [OSTI]

    Alvarez-Cohen, Lisa

    Course Syllabus: Chemistry 3AL Course Information Course Name Chemistry 3AL Course Instructor are online. Chemistry 3AL Syllabus https://elearning.berkeley.edu/AngelUploads/Content/2013SUC... 1 of 5 5

  9. Results and code predictions for ABCOVE (aerosol behavior code validation and evaluation) aerosol code validation: Test AB6 with two aerosol species. [LMFBR

    SciTech Connect (OSTI)

    Hilliard, R K; McCormack, J C; Muhlestein, L D

    1984-12-01T23:59:59.000Z

    A program for aerosol behavior code validation and evaluation (ABCOVE) has been developed in accordance with the LMFBR Safety Program Plan. The ABCOVE program is a cooperative effort between the USDOE, the USNRC, and their contractor organizations currently involved in aerosol code development, testing or application. The second large-scale test in the ABCOVE program, AB6, was performed in the 850-m/sup 3/ CSTF vessel with a two-species test aerosol. The test conditions simulated the release of a fission product aerosol, NaI, in the presence of a sodium spray fire. Five organizations made pretest predictions of aerosol behavior using seven computer codes. Three of the codes (QUICKM, MAEROS and CONTAIN) were discrete, multiple species codes, while four (HAA-3, HAA-4, HAARM-3 and SOFIA) were log-normal codes which assume uniform coagglomeration of different aerosol species. Detailed test results are presented and compared with the code predictions for seven key aerosol behavior parameters.

  10. Aerosol beam-focus laser-induced plasma spectrometer device

    DOE Patents [OSTI]

    Cheng, Meng-Dawn (Oak Ridge, TN)

    2002-01-01T23:59:59.000Z

    An apparatus for detecting elements in an aerosol includes an aerosol beam focuser for concentrating aerosol into an aerosol beam; a laser for directing a laser beam into the aerosol beam to form a plasma; a detection device that detects a wavelength of a light emission caused by the formation of the plasma. The detection device can be a spectrometer having at least one grating and a gated intensified charge-coupled device. The apparatus may also include a processor that correlates the wavelength of the light emission caused by the formation of the plasma with an identity of an element that corresponds to the wavelength. Furthermore, the apparatus can also include an aerosol generator for forming an aerosol beam from bulk materials. A method for detecting elements in an aerosol is also disclosed.

  11. iDirector with Alex Laskin: Atmospheric aerosols | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Alex Laskin: Atmospheric aerosols iDirector with Alex Laskin: Atmospheric aerosols Released: September 03, 2014 iDirector with Alex Laskin iDirector interview with EMSL scientist...

  12. Apparatus for rapid measurement of aerosol bulk chemical composition

    DOE Patents [OSTI]

    Lee, Yin-Nan E. (East Setauket, NY); Weber, Rodney J. (Atlanta, GA)

    2003-01-01T23:59:59.000Z

    An apparatus and method for continuous on-line measurement of chemical composition of aerosol particles with a fast time resolution are provided. The apparatus includes a modified particle size magnifier for producing activated aerosol particles and a collection device which collects the activated aerosol particles into a liquid stream for quantitative analysis by analytical methods. The method provided for on-line measurement of chemical composition of aerosol particles includes exposing aerosol carrying sample air to hot saturated steam thereby forming activated aerosol particles; collecting the activated aerosol particles by a collection device for delivery as a jet stream onto an impaction surface; flushing off the activated aerosol particles from the impaction surface into a liquid stream for delivery of the collected liquid stream to an analytical instrument for quantitative measurement.

  13. Apparatus for rapid measurement of aerosol bulk chemical composition

    DOE Patents [OSTI]

    Lee, Yin-Nan E.; Weber, Rodney J.; Orsini, Douglas

    2006-04-18T23:59:59.000Z

    An apparatus for continuous on-line measurement of chemical composition of aerosol particles with a fast time resolution is provided. The apparatus includes an enhanced particle size magnifier for producing activated aerosol particles and an enhanced collection device which collects the activated aerosol particles into a liquid stream for quantitative analysis by analytical means. Methods for on-line measurement of chemical composition of aerosol particles are also provided, the method including exposing aerosol carrying sample air to hot saturated steam thereby forming activated aerosol particles; collecting the activated aerosol particles by a collection device for delivery as a jet stream onto an impaction surface; and flushing off the activated aerosol particles from the impaction surface into a liquid stream for delivery of the collected liquid stream to an analytical instrument for quantitative measurement.

  14. aerosol deposition method: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and remotely sensed aerosol observations. William D. Collins; Phillip J. Rasch; Brian E. Eaton; Boris V. Khattatov; Jean-francois Lamarque; C. Zender 2001-01-01 43 Ambient aerosol...

  15. The seasonality of aerosol properties in Big Bend National Park

    E-Print Network [OSTI]

    Allen, Christopher Lee

    2007-04-25T23:59:59.000Z

    ), to characterize the seasonal variability of the Big Bend regions aerosol optical properties. Mass extinction efficiencies and relative humidity scattering enhancement factors were calculated for both externally and internally mixed aerosol populations for all size...

  16. Development of the Captive Aerosol Growth and Evolution Chamber System

    E-Print Network [OSTI]

    Antonietti, Carlos G

    2014-08-28T23:59:59.000Z

    The Captive Aerosol Growth and Evolution (CAGE) Chamber System is an tool designed to study the evolution of aerosols under conditions identical or similar to those of the surrounding environment. Our motivation was to quantify the sensitivity...

  17. aerosol particle penetration: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the subsequent aerosol penetration performance through these tubes were conducted for a aerosol particle size range of 5 nm to 20 nm and a flow rate range of 28 Lmin to 169.9...

  18. Atmospheric aerosol microphysics: Formation, characterization, and interaction. Progress report, September 1, 1991--February 28, 1994

    SciTech Connect (OSTI)

    Marlow, W.H.

    1994-12-31T23:59:59.000Z

    This project conducts theoretical and computational studies of the physical transformation processes of aerosols which underlie their atmospheric formation, interaction, transport, and removal and derives results that contribute to improved capabilities for modelling aerosol physical and chemical evolution in support of the environmental component of the National Energy Strategy. The subject of study is submicrometer aerosol particles with primary focus upon the ultrafine fraction. This report summarizes technical progress during the first two and one-half years of the project. Results of calculations of equilibrium vapor pressures over adhering pairs of 50, 100, and 200 nm particles are reported showing substantial depression of equilibrium vapor pressure relative to isolated spheres. Calculations are given of collective, long-range intermolecular energies for irregular particles to be used for growth rate calculations for realistic particles. Molecular dynamic simulations of thermal collisions of small clusters with each other and with single atoms are presented as a function of cluster size in the range from 1 to 8 atoms. Calculations of aerosol condensation in which vapor depletion and heating effects are taken into account for atmospheric cloud nucleation modelling are reported.

  19. Screen Electrode Materials & Cell Chemistries and Streamlining...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    & Cell Chemistries and Streamlining Optimization of Electrode Screen Electrode Materials & Cell Chemistries and Streamlining Optimization of Electrode 2010 DOE Vehicle Technologies...

  20. Cetane Performance and Chemistry Comparing Conventional Fuels...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Performance and Chemistry Comparing Conventional Fuels and Fuels Derived from Heavy Crude Sources Cetane Performance and Chemistry Comparing Conventional Fuels and Fuels...

  1. Nanostructure, Chemistry and Crystallography of Iron Nitride...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Nanostructure, Chemistry and Crystallography of Iron Nitride Magnetic Materials by Ultra-High-Resolution Electron Microscopy and Related Methods Nanostructure, Chemistry and...

  2. A chemistry tale of two carbons | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A chemistry tale of two carbons A chemistry tale of two carbons Released: September 03, 2012 Comprehensive field study of urban, natural emissions interacting to affect climate...

  3. The Statistical Evolution of Multiple Generations of Oxidation Products in the Photochemical Aging of Chemically Reduced Organic Aerosol

    SciTech Connect (OSTI)

    Wilson, Kevin R.; Smith, Jared D.; Kessler, Sean; Kroll, Jesse H.

    2011-10-03T23:59:59.000Z

    The heterogeneous reaction of hydroxyl radicals (OH) with squalane and bis(2-ethylhexyl) sebacate (BES) particles are used as model systems to examine how distributions of reactionproducts evolve during the oxidation of chemically reduced organic aerosol. A kinetic model of multigenerational chemistry, which is compared to previously measured (squalane) and new(BES) experimental data, reveals that it is the statistical mixtures of different generations of oxidation products that control the average particle mass and elemental composition during thereaction. The model suggests that more highly oxidized reaction products, although initially formed with low probability, play a large role in the production of gas phase reaction products.In general, these results highlight the importance of considering atmospheric oxidation as a statistical process, further suggesting that the underlying distribution of molecules could playimportant roles in aerosol formation as well as in the evolution of key physicochemical properties such as volatility and hygroscopicity.

  4. Observations of Secondary Organic Aerosol Production and Soot Aging under Atmospheric Conditions Using a Novel Environmental Aerosol Chamber

    E-Print Network [OSTI]

    Glen, Crystal

    2012-02-14T23:59:59.000Z

    of the processes leading to SOA production under ambient gaseous and particulate concentrations as well as the impact these aerosol types have on climate is poorly understood. Although the majority of atmospheric aerosols scatter radiation either directly...

  5. A numerical model of aerosol scavenging: Part 1, Microphysics parameterization

    SciTech Connect (OSTI)

    Molenkamp, C.R.; Bradley, M.M.

    1991-09-01T23:59:59.000Z

    We have developed a three-dimensional numerical model (OCTET) to simulate the dynamics and microphysics of clouds and the transport, diffusion and precipitation scavenging of aerosol particles. In this paper we describe the cloud microphysics and scavenging parameterizations. The representation of cloud microphysics is a bulk- water parameterization which includes water vapor and five types of hydrometeors (cloud droplets, rain drops, ice crystals, snow, and graupel). A parallel parameterization represents the scavenging interactions between pollutant particles and hydrometeors including collection of particles because of condensation nucleation, Brownian and phoretic attachment, and inertial capture, resuspension because of evaporation and sublimation; and transfer interactions where particles collected by one type of hydrometeor are transferred to another type of freezing, melting, accretion, riming and autoconversion.

  6. Sulfuric acid deposition from stratospheric geoengineering with sulfate aerosols

    E-Print Network [OSTI]

    Robock, Alan

    aerosols can potentially result in an increase in acid deposition. [4] Acid rain has been studiedSulfuric acid deposition from stratospheric geoengineering with sulfate aerosols Ben Kravitz,1 Alan limit of hydration of all sulfate aerosols into sulfuric acid. For annual injection of 5 Tg of SO2

  7. Volume 8 No.1 -Summer 2011 Science & Aerosols

    E-Print Network [OSTI]

    Chen, Ying

    Volume 8 No.1 - Summer 2011 1 Science & Aerosols How advances in spectroscopy may change climate clues to galaxy formation 04Science & Aerosols How advances in spectroscopy may change climate science. No university buildings were injured in the making of this photo! #12;Volume 8 No.1 - Summer 2011 5 &aerosols

  8. SUNLIGHT TRANSMISSION THROUGH DESERT DUST AND MARINE AEROSOLS: DIFFUSE LIGHT

    E-Print Network [OSTI]

    SUNLIGHT TRANSMISSION THROUGH DESERT DUST AND MARINE AEROSOLS: DIFFUSE LIGHT CORRECTIONS TO SUN transmission through desert dust and marine aerosols: Diffuse light corrections to Sun photometry 2004; published 27 April 2004. [1] Desert dust and marine aerosols are receiving increased scientific

  9. Phase transformation and growth of hygroscopic aerosols

    SciTech Connect (OSTI)

    Tang, I.N.

    1999-11-01T23:59:59.000Z

    Ambient aerosols play an important role in many atmospheric processes affecting air quality, visibility degradation, and climatic changes as well. Both natural and anthropogenic sources contribute to the formation of ambient aerosols, which are composed mostly of sulfates, nitrates, and chlorides in either pure or mixed forms. These inorganic salt aerosols are hygroscopic by nature and exhibit the properties of deliquescence and efflorescence in humid air. For pure inorganic salt particles with diameter larger than 0.1 micron, the phase transformation from a solid particle to a saline droplet occurs only when the relative humidity in the surrounding atmosphere reaches a certain critical level corresponding to the water activity of the saturated solution. The droplet size or mass in equilibrium with relative humidity can be calculated in a straightforward manner from thermodynamic considerations. For aqueous droplets 0.1 micron or smaller, the surface curvature effect on vapor pressure becomes important and the Kelvin equation must be used.

  10. A study of the direct and indirect effects of aerosols using global satellite data sets of aerosol and cloud parameters

    E-Print Network [OSTI]

    Daniel, Rosenfeld

    regions consistent with the global mean statistics. However, the effective cloud particle radius showedA study of the direct and indirect effects of aerosols using global satellite data sets of aerosol between aerosol and cloud parameters derived from satellite remote sensing for evaluating the radiative

  11. Indian Summer Monsoon Drought 2009: Role of Aerosol and Cloud Microphysics

    SciTech Connect (OSTI)

    Hazra, Anupam; Taraphdar, Sourav; Halder, Madhuparna; Pokhrel, S.; Chaudhari, H. S.; Salunke, K.; Mukhopadhyay, P.; Rao, S. A.

    2013-07-01T23:59:59.000Z

    Cloud dynamics played a fundamental role in defining Indian summer monsoon (ISM) rainfall during drought in 2009. The anomalously negative precipitation was consistent with cloud properties. Although, aerosols inhibited the growth of cloud effective radius in the background of sparse water vapor, their role is secondary. The primary role, however, is played by the interactive feedback between cloud microphysics and dynamics owing to reduced efficient cloud droplet growth, lesser latent heating release and shortage of water content. Cloud microphysical processes were instrumental for the occurrence of ISM drought 2009.

  12. Apparatus for sampling and characterizing aerosols

    DOE Patents [OSTI]

    Dunn, Patrick F. (Downers Grove, IL); Herceg, Joseph E. (Naperville, IL); Klocksieben, Robert H. (Park Forest, IL)

    1986-01-01T23:59:59.000Z

    Apparatus for sampling and characterizing aerosols having a wide particle size range at relatively low velocities may comprise a chamber having an inlet and an outlet, the chamber including: a plurality of vertically stacked, successive particle collection stages; each collection stage includes a separator plate and a channel guide mounted transverse to the separator plate, defining a labyrinthine flow path across the collection stage. An opening in each separator plate provides a path for the aerosols from one collection stage to the next. Mounted within each collection stage are one or more particle collection frames.

  13. Aerodynamic Focusing Of High-Density Aerosols

    SciTech Connect (OSTI)

    Ruiz, D. E.; Fisch, Nathaniel

    2014-02-24T23:59:59.000Z

    High-density micron-sized particle aerosols might form the basis for a number of applications in which a material target with a particular shape might be quickly ionized to form a cylindrical or sheet shaped plasma. A simple experimental device was built in order to study the properties of high-density aerosol focusing for 1#22; m silica spheres. Preliminary results recover previous findings on aerodynamic focusing at low densities. At higher densities, it is demonstrated that the focusing properties change in a way which is consistent with a density dependent Stokes number.

  14. Near real time vapor detection and enhancement using aerosol adsorption

    DOE Patents [OSTI]

    Novick, V.J.; Johnson, S.A.

    1999-08-03T23:59:59.000Z

    A vapor sample detection method is described where the vapor sample contains vapor and ambient air and surrounding natural background particles. The vapor sample detection method includes the steps of generating a supply of aerosol that have a particular effective median particle size, mixing the aerosol with the vapor sample forming aerosol and adsorbed vapor suspended in an air stream, impacting the suspended aerosol and adsorbed vapor upon a reflecting element, alternatively directing infrared light to the impacted aerosol and adsorbed vapor, detecting and analyzing the alternatively directed infrared light in essentially real time using a spectrometer and a microcomputer and identifying the vapor sample. 13 figs.

  15. Near real time vapor detection and enhancement using aerosol adsorption

    DOE Patents [OSTI]

    Novick, Vincent J. (Downers Grove, IL); Johnson, Stanley A. (Countryside, IL)

    1999-01-01T23:59:59.000Z

    A vapor sample detection method where the vapor sample contains vapor and ambient air and surrounding natural background particles. The vapor sample detection method includes the steps of generating a supply of aerosol that have a particular effective median particle size, mixing the aerosol with the vapor sample forming aerosol and adsorbed vapor suspended in an air stream, impacting the suspended aerosol and adsorbed vapor upon a reflecting element, alternatively directing infrared light to the impacted aerosol and adsorbed vapor, detecting and analyzing the alternatively directed infrared light in essentially real time using a spectrometer and a microcomputer and identifying the vapor sample.

  16. Advanced Chemistry Basins Model

    SciTech Connect (OSTI)

    Blanco, Mario; Cathles, Lawrence; Manhardt, Paul; Meulbroek, Peter; Tang, Yongchun

    2003-02-13T23:59:59.000Z

    The objective of this project is to: (1) Develop a database of additional and better maturity indicators for paleo-heat flow calibration; (2) Develop maturation models capable of predicting the chemical composition of hydrocarbons produced by a specific kerogen as a function of maturity, heating rate, etc.; assemble a compositional kinetic database of representative kerogens; (3) Develop a 4 phase equation of state-flash model that can define the physical properties (viscosity, density, etc.) of the products of kerogen maturation, and phase transitions that occur along secondary migration pathways; (4) Build a conventional basin model and incorporate new maturity indicators and data bases in a user-friendly way; (5) Develop an algorithm which combines the volume change and viscosities of the compositional maturation model to predict the chemistry of the hydrocarbons that will be expelled from the kerogen to the secondary migration pathways; (6) Develop an algorithm that predicts the flow of hydrocarbons along secondary migration pathways, accounts for mixing of miscible hydrocarbon components along the pathway, and calculates the phase fractionation that will occur as the hydrocarbons move upward down the geothermal and fluid pressure gradients in the basin; and (7) Integrate the above components into a functional model implemented on a PC or low cost workstation.

  17. Aerosol-measurement techniques developed for nuclear-reactor-accident simulations

    SciTech Connect (OSTI)

    Novick, V.J.

    1989-01-01T23:59:59.000Z

    The purpose of this research is to investigate and develop techniques for sampling aerosols from a high temperature, high pressure environment. As such, much of this research can be applied to any high temperature, high pressure sampling problem. There are four parts that must be considered in any reactor sampling system: First, the sampling tip is important from the standpoint of (1) representatively sampling the ambient particles, (2) withstanding the high temperatures in the near core region, (3) rapidly reducing the temperature of the sampled gas without causing severe thermophoretic losses or condensing gases onto existing aerosols. The second part of the system is the aerosol transport. The dynamics that must be considered include diffusion, thermophoresis, setting and impaction. The third part involves the collection or analysis of the aerosols. Finally, the ability to control the flow rate through the sampling system affects the first three parts. All four areas are analyzed theoretically for general applications. Experiments were performed on various aspects of the problem that were not dealt with by other researchers or were specific to the experiments performed in the Loss of Fluid Test (LOFT) reactor and the Power Burst Facility (PBF) reactor. Specifically this work includes (1) sampling tip analysis, (2) experimental and theoretical aerosol transport analysis, (3) the development and testing of a new multistage virtual impactor, (4) the analysis and development of a new method of measuring particle concentration using series light extinction cells, and (5) analysis and experimentally determined capabilities and usefulness of a flow control system for experimentally decreasing pressures and changing argon-steam-hydrogen gas compositions.

  18. National Nuclear Chemistry Summer School

    Broader source: Energy.gov [DOE]

    The Division of Nuclear Chemistry and Technology of the American Chemical Society (ACS) is sponsoring two INTENSIVE six-week Summer Schools in Nuclear and Radiochemistry for undergraduates. Funding is provided by the US Department of Energy.

  19. National Nuclear Chemistry Summer School

    Broader source: Energy.gov [DOE]

    he Division of Nuclear Chemistry and Technology of the American Chemical Society (ACS) is sponsoring two INTENSIVE six-week Summer Schools in Nuclear and Radiochemistry for undergraduates. Funding...

  20. Organic aerosol components observed in Northern Hemispheric datasets from Aerosol Mass Spectrometry

    E-Print Network [OSTI]

    Kroll, Jesse

    In this study we compile and present results from the factor analysis of 43 Aerosol Mass Spectrometer (AMS) datasets (27 of the datasets are reanalyzed in this work). The components from all sites, when taken together, ...

  1. Pretest aerosol code comparisons for LWR aerosol containment tests LA1 and LA2

    SciTech Connect (OSTI)

    Wright, A.L.; Wilson, J.H.; Arwood, P.C.

    1986-01-01T23:59:59.000Z

    The Light-Water-Reactor (LWR) Aerosol Containment Experiments (LACE) are being performed in Richland, Washington, at the Hanford Engineering Development Laboratory (HEDL) under the leadership of an international project board and the Electric Power Research Institute. These tests have two objectives: (1) to investigate, at large scale, the inherent aerosol retention behavior in LWR containments under simulated severe accident conditions, and (2) to provide an experimental data base for validating aerosol behavior and thermal-hydraulic computer codes. Aerosol computer-code comparison activities are being coordinated at the Oak Ridge National Laboratory. For each of the six LACE tests, ''pretest'' calculations (for code-to-code comparisons) and ''posttest'' calculations (for code-to-test data comparisons) are being performed. The overall goals of the comparison effort are (1) to provide code users with experience in applying their codes to LWR accident-sequence conditions and (2) to evaluate and improve the code models.

  2. Two Hundred Fifty Years of Aerosols and Climate: The End of the Age of Aerosols

    SciTech Connect (OSTI)

    Smith, Steven J.; Bond, Tami C.

    2014-01-20T23:59:59.000Z

    Carbonaceous and sulfur aerosols have a substantial global and regional influence on climate in addition to their impact on health and ecosystems. The magnitude of this influence has changed substantially over the past and is expected to continue to change into the future. An integrated picture of the changing climatic influence of black carbon, organic carbon and sulfate over the period 1850 through 2100, focusing on uncertainty, is presented using updated historical inventories and a coordinated set of emission projections. While aerosols have had a substantial impact on climate over the past century, by the end of the 21st century aerosols will likely be only a minor contributor to radiative forcing due to increases in greenhouse gas forcing and a global decrease in pollutant emissions. This outcome is even more certain under a successful implementation of a policy to limit greenhouse gas emissions as low-carbon energy technologies that do not emit appreciable aerosol or SO2 are deployed.

  3. Effect of Hydrophobic Primary Organic Aerosols on Secondary Organic Aerosol Formation from Ozonolysis of ?-Pinene

    SciTech Connect (OSTI)

    Song, Chen; Zaveri, Rahul A.; Alexander, M. Lizabeth; Thornton, Joel A.; Madronich, Sasha; Ortega, John V.; Zelenyuk, Alla; Yu, Xiao-Ying; Laskin, Alexander; Maughan, A. D.

    2007-10-16T23:59:59.000Z

    Semi-empirical secondary organic aerosol (SOA) models typically assume a well-mixed organic aerosol phase even in the presence of hydrophobic primary organic aerosols (POA). This assumption significantly enhances the modeled SOA yields as additional organic mass is made available to absorb greater amounts of oxidized secondary organic gases than otherwise. We investigate the applicability of this critical assumption by measuring SOA yields from ozonolysis of ?-pinene (a major biogenic SOA precursor) in a smog chamber in the absence and in the presence of dioctyl phthalate (DOP) and lubricating oil seed aerosol. These particles serve as surrogates for urban hydrophobic POA. The results show that these POA did not enhance the SOA yields. If these results are found to apply to other biogenic SOA precursors, then the semi-empirical models used in many global models would predict significantly less biogenic SOA mass and display reduced sensitivity to anthropogenic POA emissions than previously thought.

  4. Status of the ORNL Aerosol Release and Transport Project

    SciTech Connect (OSTI)

    Adams, R.E.

    1985-01-01T23:59:59.000Z

    The behavior of aerosols assumed to be characteristic of those generated during light water reactor (LWR) accident sequences and released into containment is being studied. Recent activities in the ORNL Aerosol Release and Transport Project include studies of (1) the thermal hydraulic conditions existing during Nuclear Safety Pilot Plant (NSPP) aerosol tests in steam-air environments, (2) the thermal output and aerosol mass generation rates for plasma torch aerosol generators, and (3) the influence of humidity on the shape of agglomerated aerosols of various materials. A new Aerosol-Moisture Interaction Test (AMIT) facility was prepared at the NSPP site to accommodate the aerosol shape studies; several tests with Fe/sub 2/O/sub 3/ aerosol have been conducted. In addition to the above activities a special study was conducted to determine the suitability of the technique of aerosol production by plasma torch under the operating conditions of future tests of the LWR Aerosol Containment Experiments (LACE) at the Hanford Engineering Development Laboratory. 3 refs., 2 figs., 7 tabs.

  5. Change in atmospheric mineral aerosols in response to climate: Last glacial period, preindustrial, modern, and doubled carbon dioxide climates

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    parameters on mineral aerosol mobilization, transport, andand L. Kiehl (2003), Mineral aerosol and cloud interactions,for paleoclimate, in Dust Aerosols, Loess Soils and Global

  6. Real-time characterization of particle-bound polycyclic aromatic hydrocarbons in ambient aerosols and from motor-vehicle exhaust

    E-Print Network [OSTI]

    Polidori, A.; Hu, S.; Biswas, S.; Delfino, R. J; Sioutas, C.

    2008-01-01T23:59:59.000Z

    between in-situ, real-time aerosol photoemis- sion intensityconcentration in combustion aerosols, Water, Air, Soilin-use commercial aircraft, Aerosol Sci. Tech. , 39(8), 799–

  7. Examination of the Effects of Sea Salt Aerosols on Southeast Texas Ozone and Secondary Organic Aerosol

    E-Print Network [OSTI]

    Benoit, Mark David

    2013-02-06T23:59:59.000Z

    condensation nuclei CPC Cloud condensation nuclei counter e-PTFE Expanded polytetrafluoroethylene HR-ToF-AMS High-resolution time-of-flight mass spectrometer HTDMA Humidified Tandem Differential Mobility Analyzer GHG Greenhouse Gas..., but their remains a gap in research of the aging process of sea salt aerosols, their impact on a polluted environment, and their role in heterogeneous reactions of gas phase species. The evolution of sea salt aerosols in the atmosphere results from interactions...

  8. CHEMISTRY 2011 Academic regulations for the Bachelor's degree in Chemistry 2011

    E-Print Network [OSTI]

    CHEMISTRY 2011 Academic regulations for the Bachelor's degree in Chemistry 2011 1. Framework) in Chemistry. Academic line and main subject areas of the degree The Bachelor's degree in Chemistry students a basic introduction to the Chemistry disciplines. In addition, the Bachelor's degree programme

  9. A new aerosol collector for quasi on-line analysis of particulate organic matter: the Aerosol Collection Module (ACM) and first applications with a GC/MS-FID

    E-Print Network [OSTI]

    Hohaus, T.

    In many environments organic matter significantly contributes to the composition of atmospheric aerosol particles influencing its properties. Detailed chemical characterization of ambient aerosols is critical in order to ...

  10. Attachment of radon progeny to cigarette-smoke aerosols

    SciTech Connect (OSTI)

    Biermann, A.H.; Sawyer, S.R.

    1995-05-01T23:59:59.000Z

    The daughter products of radon gas are now recognized as a significant contributor to radiation exposure to the general public. It is also suspected that a synergistic effect exists with the combination cigarette smoking and radon exposure. We have conducted an experimental investigation to determine the physical nature of radon progeny interactions with cigarette smoke aerosols. The size distributions of the aerosols are characterized and attachment rates of radon progeny to cigarette-smoke aerosols are determined. Both the mainstream and sidestream portions of the smoke aerosol are investigated. Unattached radon progeny are very mobile and, in the presence of aerosols, readily attach to the particle surfaces. In this study, an aerosol chamber is used to contain the radon gas, progeny and aerosol mixture while allowing the attachment process to occur. The rate of attachment is dependent on the size distribution, or diffusion coefficient, of the radon progeny as well as the aerosol size distribution. The size distribution of the radon daughter products is monitored using a graded-screen diffusion battery. The diffusion battery also enables separation of the unattached radon progeny from those attached to the aerosol particles. Analysis of the radon decay products is accomplished using alpha spectrometry. The aerosols of interest are size fractionated with the aid of a differential mobility analyzer and cascade impactor. The measured attachment rates of progeny to the cigarette smoke are compared to those found in similar experiments using an ambient aerosol. The lowest attachment coefficients observed, {approximately}10{sup {minus}6} cm{sup 3}/s, occurred for the ambient aerosol. The sidestream and mainstream smoke aerosols exhibited higher attachment rates in that order. The results compared favorably with theories describing the coagulation process of aerosols.

  11. Results from simulated upper-plenum aerosol transport and aerosol resuspension experiments

    SciTech Connect (OSTI)

    Wright, A.L.; Pattison, W.L.

    1984-01-01T23:59:59.000Z

    Recent calculational results published as part of the Battelle-Columbus BMI-2104 source term study indicate that, for some LWR accident sequences, aerosol deposition in the reactor primary coolant system (PCS) can lead to significant reductions in the radionuclide source term. Aerosol transport and deposition in the PCS have been calculated in this study using the TRAP-MELT 2 computer code, which was developed at Battelle-Columbus; the status of validation of the TRAP-MELT 2 code has been described in an Oak Ridge National Laboratory (ORNL) report. The objective of the ORNL TRAP-MELT Validation Project, which is sponsored by the Fuel Systems Behavior Research Branch of the US Nuclear Regulatory Commission, is to conduct simulated reactor-vessel upper-plenum aerosol deposition and transport tests. The results from these tests will be used in the ongoing effort to validate TRAP-MELT 2. The TRAP-MELT Validation Project includes two experimental subtasks. In the Aerosol Transport Tests, aerosol transport in a vertical pipe is being studied; this geometry was chosen to simulate aerosol deposition and transport in the reactor-vessel upper-plenum. To date, four experiments have been performed; the results from these tests are presented in this paper. 7 refs., 4 figs., 4 tabs.

  12. Calibration of the On-Line Aerosol Monitor (OLAM) with ammonium chloride and sodium chloride aerosols

    SciTech Connect (OSTI)

    Brockmann, J.E.; Lucero, D.A.; Romero, T. [Sandia National Labs., Albuquerque, NM (United States); Pentecost, G. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1993-12-01T23:59:59.000Z

    The On-Line Aerosol Monitor (OLAM) is a light attenuation device designed and built at the Idaho National Engineering Laboratory (INEL) by EG&G Idaho. Its purpose is to provide an on-line indication of aerosol concentration in the PHEBUS-FP tests. It does this by measuring the attenuation of a light beam across a tube through which an aerosol is flowing. The OLAM does not inherently give an absolute response and must be calibrated. A calibration has been performed at Sandia National Laboratories` (SNL) Sandia Aerosol Research Laboratory (SARL) and the results are described here. Ammonium chloride and sodium chloride calibration aerosols are used for the calibration and the data for the sodium chloride aerosol is well described by a model presented in this report. Detectable instrument response is seen over a range of 0.1 cm{sup 3} of particulate material per m{sup 3} of gas to 10 cm{sup 3} of particulate material per m{sup 3} of gas.

  13. Group Report: Connections between Aerosol Properties

    E-Print Network [OSTI]

    Schwartz, Stephen E.

    14 Group Report: Connections between Aerosol Properties and Forcing of Climate S.E. XMWRZ, Rapporteur F.ARNOLD,J.-p.BLANCHET,PA. DURKEE, D.J.HOFMANN,W.A. HOPPEL, M.D. KING, A.A. LACE, T. NAKAJIMA

  14. Aerosolcloudprecipitation interactions. Part 1. The nature and sources of cloud-active aerosols

    E-Print Network [OSTI]

    Rutledge, Steven

    Aerosol­cloud­precipitation interactions. Part 1. The nature and sources of cloud-active aerosols M Available online 13 March 2008 Keywords: aerosol precipitation CCN emissions clouds Atmospheric aerosol the chemical composition of aerosols, their microphysical properties, and the factors that enable them to act

  15. Direct and semidirect aerosol effects of Southern African biomass burning aerosol

    SciTech Connect (OSTI)

    Sakaeda, Naoko; Wood, Robert; Rasch, Philip J.

    2011-06-21T23:59:59.000Z

    The direct and semi-direct radiative effects of biomass burning aerosols from Southern African fires during July-October are investigated using 20 year runs of the Community Atmospheric Model (CAM) coupled to a slab ocean model. The aerosol optical depth is constrained using observations in clear skies from MODIS and for aerosol layers above clouds from CALIPSO. Over the ocean, where the absorbing biomass burning aerosol layers are primarily located above cloud, negative top of atmosphere (TOA) semi-direct radiative effects associated with increased low cloud cover dominate over a weaker positive all-sky direct radiative effect (DRE). In contrast, over the land where the aerosols are often below or within cloud layers, reductions in cloud liquid water path (LWP) lead to a positive semi-direct radiative effect that dominates over a near-zero DRE. Over the ocean, the cloud response can be understood as a response to increased lower tropospheric stability (LTS) which is caused both by aerosol absorptive warming in overlying layers and surface cooling in response to direct aerosol forcing. The ocean cloud changes are robust to changes in the cloud parameterization (removal of the hard-wired dependence of clouds on LTS), suggesting that they are physically realistic. Over land where cloud cover changes are minimal, decreased LWP is consistent with weaker convection driven by increased static stability. Over the entire region the overall TOA radiative effect from the biomass burning aerosols is almost zero due to opposing effects over the land and ocean. However, the surface forcing is strongly negative requiring a reduction in precipitation. This is primarily realized through reductions in convective precipitation on both the southern and northern flanks of the convective precipitation region spanning the equatorial rainforest and the ITCZ in the southern Sahel. The changes are consistent with the low-level aerosol forced cooling pattern. The results highlight the importance of semi-direct radiative effects and precipitation responses for determining the climatic effects of aerosols in the African region.

  16. Aerosol Properties and Radiative Forcing over Kanpur during Severe Aerosol Loading Conditions

    SciTech Connect (OSTI)

    Kaskaoutis, D. G.; Sinha, P. R.; Vinoj, V.; Kosmopoulos, P. G.; Tripathi, S. N.; Misra, Amit; Sharma, M.; Singh, R. P.

    2013-11-01T23:59:59.000Z

    Atmospheric aerosols over India exhibit large spatio-temporal fluctuation driven by the local monsoon system, emission rates and seasonally-changed air masses. The northern part of India is well-known for its high aerosol loading throughout the year due to anthropogenic emissions, dust influence and biomass burning. On certain circumstances and, under favorable weather conditions, the aerosol load can be severe, causing significant health concerns and climate implications. The present work analyzes the aerosol episode (AE) days and examines the modification in aerosol properties and radiative forcing during the period 2001-2010 based on Kanpur-AERONET sun photometer data. As AEs are considered the days having daily-mean aerosol optical depth (AOD) above the decadal mean + 1 STD (standard deviation); the threshold value is defined at 0.928. The results identify 277 out of 2095 days (13.2%) of AEs over Kanpur, which are most frequently observed during post-monsoon (78 cases, 18.6%) and monsoon (76, 14.7%) seasons due to biomass-burning episodes and dust influence, respectively. On the other hand, the AEs in winter and pre-monsoon are lower in both absolute and percentage values (65, 12.5% and 58, 9.1%, respectively). The modification in aerosol properties on the AE days is strongly related to season. Thus, in post-monsoon and winter the AEs are associated with enhanced presence of fine-mode aerosols and Black Carbon from anthropogenic pollution and any kind of burning, while in pre-monsoon and monsoon seasons they are mostly associated with transported dust. Aerosol radiative forcing (ARF) calculated using SBDART shows much more surface (~-69 to -97 Wm-2) and Top of Atmosphere cooling (-20 to -30 Wm-2) as well as atmospheric heating (~43 to 71 Wm-2) during the AE days compared to seasonal means. These forcing values are mainly controlled by the higher AODs and the modified aerosol characteristics (Angstrom ?, SSA) during the AE days in each season and may cause severe climate implications over Ganges Basin with further consequences on atmospheric heating, cloud microphysics, monsoon rainfall and melting of Himalayan glaciers.

  17. Environmental Chamber Study of Atmospheric Chemistry and Secondary Organic Aerosol Formation Using Cavity Enhanced Absorption Spectroscopy

    E-Print Network [OSTI]

    Liu, Yingdi

    2011-01-01T23:59:59.000Z

    can either be a xenon arc lamp or an LED. A focusing lens isemitting diode (LED) or xenon arc lamp is sufficient as alight from an LED or xenon arc lamp. In this case, we

  18. Carbon oxidation state as a metric for describing the chemistry of atmospheric organic aerosol

    E-Print Network [OSTI]

    Kroll, Jesse

    A detailed understanding of the sources, transformations and fates of organic species in the environment is crucial because of the central roles that they play in human health, biogeochemical cycles and the Earth's climate. ...

  19. A VIBRATIONAL SPECTROSCOPIC STUDY OF AQUEOUS HYDROGEN HALIDE SOLUTIONS: APPLICATION TO ATMOSPHERIC AEROSOL CHEMISTRY

    E-Print Network [OSTI]

    to thank Carri, Misty, Kelly, and Mindy, who provided the comic relief and road trips that helped me keep

  20. EMSL Science Theme Advisory Panel Workshop - Atmospheric Aerosol Chemistry, Climate Change, and Air Quality

    SciTech Connect (OSTI)

    Baer, Donald R.; Finlayson-Pitts, Barbara J.; Allen, Heather C.; Bertram, Allan K.; Grassian, Vicki H.; Martin, Scot T.; Penner, Joyce E.; Prather, Kimberly; Rasch, Philip J.; Signorell, Ruth; Smith, James N.; Wyslouzil, Barbara; Ziemann, Paul; Dabdub, Donald; Furche, Filipp; Nizkorodov, Sergey; Tobias, Douglas J.; Laskin, Julia; Laskin, Alexander

    2013-07-01T23:59:59.000Z

    This report contains the workshop scope and recommendations from the workshop attendees in identifying scientific gaps in new particle formation, growth and properties of particles and reactions in and on particles as well as the laboratory-focused capabilities, field-deployable capabilities and modeling/theory tools along with linking of models to fundamental data.

  1. Emission and Chemistry of Organic Carbon in the Gas and Aerosol...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Finally, the influence of biomass burning is investigated using the measurements of acetonitrile, which was found to correlate with levoglucosan in the particle phase. Diurnal...

  2. Recent activities in the Aerosol Generation and Transport Program

    SciTech Connect (OSTI)

    Adams, R.E.

    1984-01-01T23:59:59.000Z

    General statements may be made on the behavior of single-component and multi-component aerosols in the Nuclear Safety Pilot Plant vessel. The removal processes for U/sub 3/O/sub 8/, Fe/sub 2/O/sub 3/, and U/sub 3/O/sub 8/ + Fe/sub 2/O/sub 3/ aerosols are enhanced in a steam-air atmosphere. Steam-air seems to have little effect on removal of concrete aerosol from the vessel atmosphere. A steam-air environment causes a change in aerosol shape from chain-agglomerate to basically spherical for U/sub 3/O/sub 8/, Fe/sub 2/O/sub 3/, and U/sub 3/O/sub 8/ + Fe/sub 2/O/sub 3/ aerosol; for concrete the change in aerosol shape is from chain-agglomerate to partially spherical. The mass ratio of the individual components of a multi-component aerosol seems to have an observable influence on the resultant behavior of these aerosols in steam. The enhanced rate of removal of the U/sub 3/O/sub 8/, the Fe/sub 2/O/sub 3/, and the mixed U/sub 3/O/sub 8/ + Fe/sub 2/O/sub 3/ aerosols from the atmosphere of the NSPP vessel by steam-air is probably caused by the change in aerosol shape and the condensation of steam on the aerosol surfaces combining to increase the effect of gravitational settling. The apparent lack of an effect by steam-air on the removal rate of concrete aerosol could result from a differing physical/chemical response of the surfaces of this aerosol to condensing steam.

  3. The mechano-chemistry of cytoskeletal force generation

    E-Print Network [OSTI]

    Mirko Maraldi; Krishna Garikipati

    2014-04-23T23:59:59.000Z

    In this communication, we propose a model to study the non-equilibrium process by which actin stress fibers develop force in contractile cells. The emphasis here is on the non-equilibrium thermodynamics, which is necessary to address the mechanics as well as the chemistry of dynamic cell contractility. In this setting we are able to develop a framework that relates (a) the dynamics of force generation within the cell and (b) the cell response to external stimuli to the chemical processes occurring within the cell, as well as to the mechanics of linkage between the stress fibers, focal adhesions and extra-cellular matrix.

  4. CFD modeling and image analysis of exhaled aerosols due to a growing bronchial tumor: Towards non-invasive diagnosis and treatment of respiratory obstructive diseases

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Xi, Jinxiang; Kim, JongWon; Si, Xiuhua A.; Corley, Richard A.; Kabilan, Senthil; Wang, Shengyu

    2015-01-01T23:59:59.000Z

    Diagnosis and prognosis of tumorigenesis are generally performed with CT, PET, or biopsy. Such methods are accurate, but have the limitations of high cost and posing additional health risks to patients. In this study, we introduce an alternative computer aided diagnostic tool that can locate malignant sites caused by tumorigenesis in a non-invasive and low-cost way. Our hypothesis is that exhaled aerosol distribution is unique to lung structure and is sensitive to airway structure variations. With appropriate approaches, it is possible to locate the disease site, determine the disease severity, and subsequently formulate a targeted drug delivery plan to treatmore »the disease. This study numerically evaluated the feasibility of the proposed breath test in an image-based lung model with varying pathological stages of a bronchial squamous tumor. Large eddy simulations and a Lagrangian tracking approach were used to model respiratory airflows and aerosol dynamics. Respirations of tracer aerosols of 1 ?m at a flow rate of 20 L/min were simulated, with the distributions of exhaled aerosols recorded on a filter at the mouth exit. Aerosol patterns were quantified with multiple analytical techniques such as concentration disparity, spatial scanning and fractal analysis. We demonstrated that a growing bronchial tumor induced notable variations in both the airflow and exhaled aerosol distribution. These variations became more apparent with increasing tumor severity. The exhaled aerosols exhibited distinctive pattern parameters such as spatial probability, fractal dimension, and multifractal spectrum. Results of this study show that morphometric measures of the exhaled aerosol pattern can be used to detect and monitor the pathological states of respiratory diseases in the upper airway. The proposed breath test also has the potential to locate the site of the disease, which is critical in developing a personalized, site-specific drug delivery protocol.« less

  5. 1997 Atmospheric Chemistry Colloquium for Emerging Senior Scientists

    SciTech Connect (OSTI)

    Paul H. Wine

    1998-11-23T23:59:59.000Z

    DOE's Atmospheric Chemistry Program is providing partial funding for the Atmospheric Chemistry Colloquium for Emerging Senior Scientists (ACCESS) and FY 1997 Gordon Research Conference in Atmospheric Chemistry

  6. analytical chemistry organic: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of Electronic Structure and Laser, Foundation for Research and Technology 25 SYLLABUS for CHEMISTRY 2310 ORGANIC CHEMISTRY 1 Chemistry Websites Summary: Discussion...

  7. applied chemistry organic: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of Electronic Structure and Laser, Foundation for Research and Technology 18 SYLLABUS for CHEMISTRY 2310 ORGANIC CHEMISTRY 1 Chemistry Websites Summary: Discussion...

  8. Impact of natural and anthropogenic aerosols on stratocumulus and precipitation in the Southeast Pacific: A regional modeling study using WRF-Chem

    SciTech Connect (OSTI)

    Yang, Qing; Gustafson, William I.; Fast, Jerome D.; Wang, Hailong; Easter, Richard C.; Wang, Minghuai; Ghan, Steven J.; Berg, Larry K.; Leung, Lai-Yung R.; Morrison, H.

    2012-09-28T23:59:59.000Z

    Cloud-system resolving simulations with the chemistry version of the Weather Research and Forecasting (WRF-Chem) model are used to quantify the impacts of regional anthropogenic and oceanic emissions on changes in aerosol properties, cloud macro- and microphysics, and cloud radiative forcing over the Southeast Pacific (SEP) during the VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) (15 Oct–Nov 16, 2008). The effects of oceanic aerosols on cloud properties, precipitation, and the shortwave forcing counteract those of anthropogenic aerosols. Despite the relatively small changes in Na concentrations (2-12%) from regional oceanic emissions, their net effect (direct and indirect) on the surface shortwave forcing is opposite and comparable or even larger in magnitude compared to those of regional anthropogenic emissions over the SEP. Two distinct regions are identified in the VOCALS-REx domain. The near-coast polluted region is characterized with strong droplet activation suppression of small particles by sea-salt particles, the more important role of the first than the second indirect effect, low surface precipitation rate, and low aerosol-cloud interaction strength associated with anthropogenic emissions. The relatively clean remote region is characterized with large contributions of Cloud Condensation Nuclei (CCN, number concentration denoted by NCCN) and droplet number concentrations (Nd) from non-local sources (lateral boundaries), a significant amount of surface precipitation, and high aerosol-cloud interactions under a scenario of five-fold increase in anthropogenic emissions. In the clean region, cloud properties have high sensitivity (e.g., 13% increase in cloud-top height and a 9% surface albedo increase) to the moderate increase in CCN concentration (?Nccn = 13 cm-3; 25%) produced by a five-fold increase in regional anthropogenic emissions. The increased anthropogenic aerosols reduce the precipitation amount over the relatively clean remote ocean. The reduction of precipitation (as a cloud water sink) more than doubles the wet scavenging timescale, resulting in an increased aerosol lifetime in the marine boundary layer. Therefore, the aerosol impacts on precipitation are amplified by the positive feedback of precipitation on aerosol. The positive feedback ultimately alters the cloud micro- and macro-properties, leading to strong aerosol-cloud-precipitation interactions. The higher sensitivity of clouds to anthropogenic aerosols over this region is also related to a 16% entrainment rate increase due to anthropogenic aerosols. The simulated aerosol-cloud-precipitation interactions are stronger at night over the clean marine region, while during the day, solar heating results in more frequent decoupling, thinner clouds, reduced precipitation, and reduced sensitivity to anthropogenic emissions. The simulated high sensitivity to the increased anthropogenic emissions over the clean region suggests that the perturbation of the clean marine environment with anthropogenic aerosols may have a larger effect on climate than that of already polluted marine environments.

  9. Statistical Approaches to Aerosol Dynamics for Climate Simulation

    SciTech Connect (OSTI)

    Zhu, Wei

    2014-09-02T23:59:59.000Z

    In this work, we introduce two general non-parametric regression analysis methods for errors-in-variable (EIV) models: the compound regression, and the constrained regression. It is shown that these approaches are equivalent to each other and, to the general parametric structural modeling approach. The advantages of these methods lie in their intuitive geometric representations, their distribution free nature, and their ability to offer a practical solution when the ratio of the error variances is unknown. Each includes the classic non-parametric regression methods of ordinary least squares, geometric mean regression, and orthogonal regression as special cases. Both methods can be readily generalized to multiple linear regression with two or more random regressors.

  10. Real-time detection of ambient aerosols using photothermal interferometry: Folded Jamin interferometer

    E-Print Network [OSTI]

    Real-time detection of ambient aerosols using photothermal interferometry: Folded Jamin of instrumentation that can directly measure ambient aerosol absorption through photothermal interferometry. The hallmark of this approach is its ability to directly measure aerosol absorption without interference from

  11. The impact of meteorological conditions and variation in chemical composition of aerosols on regional cloud formation

    E-Print Network [OSTI]

    Creamean, Jessie Marie

    2012-01-01T23:59:59.000Z

    MISSION A Global 3D View of Aerosols and Clouds, Bulletin ofJ.H. Seinfeld, Secondary aerosol formation from atmosphericJ.H. Seinfeld, Secondary aerosol formation from atmospheric

  12. Local Environmental Pollution Strongly Influences Culturable Bacterial Aerosols at an Urban Aquatic Superfund Site

    E-Print Network [OSTI]

    Uriarte, Maria

    Local Environmental Pollution Strongly Influences Culturable Bacterial Aerosols at an Urban Aquatic Information ABSTRACT: In polluted environments, when microbial aerosols originate locally, species composition of the aerosols should reflect the polluted source. To test the connection between local environmental pollution

  13. FOSSIL ENERGY, CO2, CLIMATE CHANGE, AND THE AEROSOL PROBLEM Stephen E. Schwartz

    E-Print Network [OSTI]

    been masked by the aerosol cooling forcing. Allowable future CO2 emissions so as not to commit of the greenhouse gas forcing due to cooling forcing by tropospheric aerosols; as aerosols, unlike CO2, are short

  14. Modeling the Direct and Indirect Effects of Atmospheric Aerosols on Tropical Cyclones

    E-Print Network [OSTI]

    Lee, Keun-Hee

    2012-02-14T23:59:59.000Z

    precipitation even in the weakest hurricane. When comparing the model performance between aerosol indirect and direct effect by ensemble experiments, the adjustment time of the circulation due to modification of the aerosol radiative forcing by aerosol layers...

  15. Aerosol indirect effects -- general circulation model intercomparison and evaluation with satellite data

    E-Print Network [OSTI]

    Quaas, Johannes

    2010-01-01T23:59:59.000Z

    such as cloud contamination or 3D radiation effects (Loebeffect relationship behind the aerosol – cloud/radiationradiation resulting in the “aerosol direct effect”. Hy- drophilic aerosols can serve as cloud

  16. Aerosol indirect effects ? general circulation model intercomparison and evaluation with satellite data

    E-Print Network [OSTI]

    Quaas, Johannes

    2010-01-01T23:59:59.000Z

    such as cloud contamination or 3D radiation effects (Loebeffect relationship behind the aerosol – cloud/radiationradiation resulting in the “aerosol direct effect”. Hy- drophilic aerosols can serve as cloud

  17. Inorganic aerosols responses to emission changes in Yangtze River Delta, China

    SciTech Connect (OSTI)

    Dong, Xinyi; Li, Juan; Fu, Joshua S.; Gao, Yang; Huang, Kan; Zhuang, Guoshun

    2014-05-15T23:59:59.000Z

    China announced the Chinese National Ambient Air Quality standards (CH-NAAQS) on Feb. 29th, 2012, and PM2.5 is for the very first time included in the standards as a criteria pollutant. In order to probe into PM2.5 pollution over Yangtze River Delta, which is one of the major urban clusters hosting more than 80 million people in China, the integrated MM5/CMAQ modeling system is applied for a full year simulation to examine the PM2.5 concentration and seasonality, and also the inorganic aerosols responses to precursor emission changes. Both simulation and observation demonstrated that, inorganic aerosols have substantial contributions to PM2.5 over YRD, ranging from 37.1% in November to 52.8% in May. Nocturnal production of nitrate (NO3-) through heterogeneous hydrolysis of N2O5 was found significantly contribute to high NO3-concentration throughout the year. We also found that in winter NO3- was even increased under nitrogen oxides (NOx) emission reduction due to higher production of N2O5 from the excessive ozone (O3) introduced by attenuated titration, which further lead to increase of ammonium (NH4+) and sulfate (SO42-), while other seasons showed decrease response of NO3-. Sensitivity responses of NO3- under anthropogenic VOC emission reduction was examined and demonstrated that in urban areas over YRD, NO3- formation was actually VOC sensitive due to the O3-involved nighttime chemistry of N2O5, while a reduction of NOx emission may have counter-intuitive effect by increasing concentrations of inorganic aerosols.

  18. MELCOR aerosol transport module modification for NSSR-1

    SciTech Connect (OSTI)

    Merrill, B.J.; Hagrman, D.L.

    1996-03-01T23:59:59.000Z

    This report describes modifications of the MELCOR computer code aerosol transport module that will increase the accuracy of calculations for safety analysis of the International Thermonuclear Experimental Reactor (ITER). The modifications generalize aerosol deposition models to consider gases other than air, add specialized models for aerosol deposition during high speed gas flows in ducts, and add models for resuspension of aerosols that are entrained in coolants when these coolants flash. Particular attention has been paid to the adhesion of aerosol particles once they are transported to duct walls. The results of calculations with the modified models have been successfully compared to data from Light Water Reactor Aerosol Containment Experiments (LACE) conducted by an international consortium at Hanford, Washington.

  19. Climate Engineering with Stratospheric Aerosols and Associated Engineering Parameters

    SciTech Connect (OSTI)

    Kravitz, Benjamin S.

    2013-02-12T23:59:59.000Z

    Climate engineering with stratospheric aerosols, an idea inspired by large volcaniceruptions, could cool the Earth’s surface and thus alleviate some of the predicted dangerous impacts of anthropogenic climate change. However, the effectiveness of climate engineering to achieve a particular climate goal, and any associated side effects, depend on certain aerosol parameters and how the aerosols are deployed in the stratosphere. Through the examples of sulfate and black carbon aerosols, this paper examines "engineering" parameters-aerosol composition, aerosol size, and spatial and temporal variations in deployment-for stratospheric climate engineering. The effects of climate engineering are sensitive to these parameters, suggesting that a particle could be found ordesigned to achieve specific desired climate outcomes. This prospect opens the possibility for discussion of societal goals for climate engineering.

  20. Total aerosol effect: forcing or radiative flux perturbation?

    SciTech Connect (OSTI)

    Lohmann, Ulrike; Storelvmo, Trude; Jones, Andy; Rotstayn, Leon; Menon, Surabi; Quaas, Johannes; Ekman, Annica; Koch, Dorothy; Ruedy, Reto

    2009-09-25T23:59:59.000Z

    Uncertainties in aerosol forcings, especially those associated with clouds, contribute to a large extent to uncertainties in the total anthropogenic forcing. The interaction of aerosols with clouds and radiation introduces feedbacks which can affect the rate of rain formation. Traditionally these feedbacks were not included in estimates of total aerosol forcing. Here we argue that they should be included because these feedbacks act quickly compared with the time scale of global warming. We show that for different forcing agents (aerosols and greenhouse gases) the radiative forcings as traditionally defined agree rather well with estimates from a method, here referred to as radiative flux perturbations (RFP), that takes these fast feedbacks and interactions into account. Thus we propose replacing the direct and indirect aerosol forcing in the IPCC forcing chart with RFP estimates. This implies that it is better to evaluate the total anthropogenic aerosol effect as a whole.

  1. Final Report for �¢����Cloud-Aerosol Physics in Super-Parameterized Atmospheric Regional Climate Simulations (CAP-SPARCS)�¢��� (DE-SC0002003) for 8/15/2009 through 8/14/2012

    SciTech Connect (OSTI)

    Lynn M. Russell; Richard C.J. Somerville

    2012-11-05T23:59:59.000Z

    Improving the representation of local and non-local aerosol interactions in state-of-the-science regional climate models is a priority for the coming decade (Zhang, 2008). With this aim in mind, we have combined two new technologies that have a useful synergy: (1) an aerosol-enabled regional climate model (Advanced Weather Research and Forecasting Model with Chemistry WRF-Chem), whose primary weakness is a lack of high quality boundary conditions and (2) an aerosol-enabled multiscale modeling framework (PNNL Multiscale Aerosol Climate Model (MACM)), which is global but captures aerosol-convection-cloud feedbacks, and thus an ideal source of boundary conditions. Combining these two approaches has resulted in an aerosol-enabled modeling framework that not only resolves high resolution details in a particular region, but crucially does so within a global context that is similarly faithful to multi-scale aerosol-climate interactions. We have applied and improved the representation of aerosol interactions by evaluating model performance over multiple domains, with (1) an extensive evaluation of mid-continent precipitation representation by multiscale modeling, (2) two focused comparisons to transport of aerosol plumes to the eastern United States for comparison with observations made as part of the International Consortium for Atmospheric Research on Transport and Transformation (ICARTT), with the first being idealized and the second being linked to an extensive wildfire plume, and (3) the extension of these ideas to the development of a new approach to evaluating aerosol indirect effects with limited-duration model runs by �¢����nudging�¢��� to observations. This research supported the work of one postdoc (Zhan Zhao) for two years and contributed to the training and research of two graduate students. Four peer-reviewed publications have resulted from this work, and ground work for a follow-on project was completed.

  2. Impact of Resolution on Simulation of Closed Mesoscale Cellular Convection Identified by Dynamically Guided Watershed Segmentation

    SciTech Connect (OSTI)

    Martini, Matus; Gustafson, William I.; Yang, Qing; Xiao, Heng

    2014-11-27T23:59:59.000Z

    Organized mesoscale cellular convection (MCC) is a common feature of marine stratocumulus that forms in response to a balance between mesoscale dynamics and smaller scale processes such as cloud radiative cooling and microphysics. We use the Weather Research and Forecasting model with chemistry (WRF-Chem) and fully coupled cloud-aerosol interactions to simulate marine low clouds during the VOCALS-REx campaign over the southeast Pacific. A suite of experiments with 3- and 9-km grid spacing indicates resolution-dependent behavior. The simulations with finer grid spacing have smaller liquid water paths and cloud fractions, while cloud tops are higher. The observed diurnal cycle is reasonably well simulated. To isolate organized MCC characteristics we develop a new automated method, which uses a variation of the watershed segmentation technique that combines the detection of cloud boundaries with a test for coincident vertical velocity characteristics. This ensures that the detected cloud fields are dynamically consistent for closed MCC, the most common MCC type over the VOCALS-REx region. We demonstrate that the 3-km simulation is able to reproduce the scaling between horizontal cell size and boundary layer height seen in satellite observations. However, the 9-km simulation is unable to resolve smaller circulations corresponding to shallower boundary layers, instead producing invariant MCC horizontal scale for all simulated boundary layers depths. The results imply that climate models with grid spacing of roughly 3 km or smaller may be needed to properly simulate the MCC structure in the marine stratocumulus regions.

  3. Molten fluoride fuel salt chemistry

    SciTech Connect (OSTI)

    Toth, L.M.; Del Cul, G.D.; Dai, S.; Metcalf, D.H. [Oak Ridge National Lab., TN (United States). Chemical Technology Div.

    1994-09-01T23:59:59.000Z

    The chemistry of molten fluorides is traced from their development as fuels in the Molten Salt Reactor Experiment with important factors in their selection being discussed. Key chemical characteristics such as solubility, redox behavior, and chemical activity are explained as they relate to the behavior of molten fluoride fuel systems. Fission product behavior is described along with processing experience. Development requirements for fitting the current state of the chemistry to modern nuclear fuel system are described. It is concluded that while much is known about molten fluoride behavior, processing and recycle of the fuel components is a necessary factor if future systems are to be established.

  4. Carbon Chemistry in interstellar clouds

    E-Print Network [OSTI]

    Maryvonne Gerin; David Fosse; Evelyne Roueff

    2002-12-03T23:59:59.000Z

    We discuss new developments of interstellar chemistry, with particular emphasis on the carbon chemistry. We confirm that carbon chains and cycles are ubiquitous in the ISM and closely chemically related to ea ch other, and to carbon. Investigation of the carbon budget in shielded and UV illuminated gas shows that the inventory of interstellar molecules is not complete and more complex molecules with 4 or more carbon atoms must be present. Finally we discuss the consequences for the evolution of clouds and conclude that the ubiquitous presence of carbon chains and cycles is not a necessary consequence of a very young age for interstellar clouds.

  5. Chemistry, Life, and Earth Sciences

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced. C o w l i t z CPlasma of theChemistry OxideChemistry Soft

  6. The Effect of Solvent on the Analysis of Secondary Organic Aerosol Using Electrospray Ionization Mass Spectrometry

    SciTech Connect (OSTI)

    Bateman, Adam P.; Walser, Maggie L.; Dessiaterik, Yury; Laskin, Julia; Laskin, Alexander; Nizkorodov, Serguei

    2008-10-01T23:59:59.000Z

    Solvent-analyte reactions in organic aerosol (OA) extracts prepared for analysis by electrospray ionization mass spectrometry (ESI-MS) were examined. Secondary organic aerosol (SOA) produced by ozonation of d-limonene as well as several test organic chemicals with functional groups typical for OA constituents were dissolved and stored in methanol, d3-methanol, acetonitrile, and d3-acetonitrile to investigate the extent and relative rates of reactions between analyte and solvent. High resolution ESI-MS showed that reactions of carbonyls with methanol produce significant amounts of hemiacetals and acetals on time scales ranging from several minutes to several days, with the reaction rates increasing in acidified solutions. Carboxylic acid groups were observed to react with methanol resulting in the formation of esters. In contrast, acetonitrile extracts showed no evidence of reactions with analyte molecules, suggesting that acetonitrile is the preferred solvent for SOA extraction. The use of solvent-analyte reactivity as an analytical chemistry tool for the improved characterization of functional groups in complex organic mixtures was also demonstrated. Direct comparison between ESI mass spectra of the same SOA samples extracted in reactive (methanol) versus non-reactive (acetonitrile) solvents was used to estimate the relative fractions of ketones (?38%), aldehydes (?6%), and carboxylic acids (?55%) in d-limonene SOA.

  7. Aerosol Retrievals from ARM SGP MFRSR Data

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Alexandrov, Mikhail

    The Multi-Filter Rotating Shadowband Radiometer (MFRSR) makes precise simultaneous measurements of the solar direct normal and diffuse horizontal irradiances at six wavelengths (nominally 415, 500, 615, 673, 870, and 940 nm) at short intervals (20 sec for ARM instruments) throughout the day. Time series of spectral optical depth are derived from these measurements. Besides water vapor at 940 nm, the other gaseous absorbers within the MFRSR channels are NO2 (at 415, 500, and 615 nm) and ozone (at 500, 615, and 670 nm). Aerosols and Rayleigh scattering contribute atmospheric extinction in all MFRSR channels. Our recently updated MFRSR data analysis algorithm allows us to partition the spectral aerosol optical depth into fine and coarse modes and to retrieve the fine mode effective radius. In this approach we rely on climatological amounts of NO2 from SCIAMACHY satellite retrievals and use daily ozone columns from TOMS.

  8. Stackable differential mobility analyzer for aerosol measurement

    DOE Patents [OSTI]

    Cheng, Meng-Dawn (Oak Ridge, TN); Chen, Da-Ren (Creve Coeur, MO)

    2007-05-08T23:59:59.000Z

    A multi-stage differential mobility analyzer (MDMA) for aerosol measurements includes a first electrode or grid including at least one inlet or injection slit for receiving an aerosol including charged particles for analysis. A second electrode or grid is spaced apart from the first electrode. The second electrode has at least one sampling outlet disposed at a plurality different distances along its length. A volume between the first and the second electrode or grid between the inlet or injection slit and a distal one of the plurality of sampling outlets forms a classifying region, the first and second electrodes for charging to suitable potentials to create an electric field within the classifying region. At least one inlet or injection slit in the second electrode receives a sheath gas flow into an upstream end of the classifying region, wherein each sampling outlet functions as an independent DMA stage and classifies different size ranges of charged particles based on electric mobility simultaneously.

  9. Electromagnetic scattering and absorption by aerosol agglomerates

    SciTech Connect (OSTI)

    Chen, Hsingyi.

    1989-01-01T23:59:59.000Z

    Calculation of scattering and absorption by smoke aerosols is required in many applications, including characterization of atmospheric aerosols, prediction of climatic impact of smoke, evaluation of smoke effectiveness in obscuration, calculation of heat transfer from flames, and evaluation of various scenarios of nuclear winter. In this dissertation two procedures were developed to accurately make these calculations utilizing realistic models of smoke agglomerates including oriented chains and fractal geometries. First the Iterative Extended Boundary Condition Method (IEBCM) was utilized to calculate the electromagnetic (EM) scattering and absorption of elongated aerosol particles. The computation efficiency and capability of IEBCM were improved by implementing the sectioning and the segmentation procedures. The sectioning procedure resulted in improving the computational efficiency and the segmentation method made it possible to make calculations for particles with aspect ratios as high as 250. The other procedure employed the Volume Integral Equation Formulation (VIEF) to compute the EM scattering and absorption by agglomerates of complex geometries. The validity of the procedure was checked first by comparing the obtained results with those obtained from the Mie solution for a spherical object and with the IEBCM for nonspherical objects. The comparison between results showed excellent agreement and hence validated the accuracy of the VIEF. The VIEF solution was then used to make calculations for five types of fractal agglomerates of smoke aerosol particles with fractal dimensions in the range from 1.7 to 1.9. The results obtained were compared with those based on the fractal theory recently published by Berry and Percival, and some differences were observed.

  10. aerosols influencing atmospheric: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and other anthropogenic influences have substantially altered the composition and size-distribution of atmospheric aerosol particles over the last century. This, in turn,...

  11. aerodyne aerosol mass: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    independent measurements of fine particle volume or particle-into-liquid sampler (PILS) ion chromatography measurements for 3 field campaigns with different dominant aerosol...

  12. aerosol particle concentration: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the chemical and physical characterization of aerosols using a single particle mass spectrometry based technique University of California eScholarship Repository Summary: Real-...

  13. aerosol particle charger: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Introduction The Universal Serial Bus (USB) port Allen, Jont 9 New approaches for the chemical and physical characterization of aerosols using a single particle mass spectrometry...

  14. aerosol mass spectrometer: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004. The concentration of a species Zhang, Qi 8 Development of a thermal desorption chemical ionization mobility mass spectrometer for the speciation of ultrafine aerosols. Open...

  15. aerosol particles generated: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the chemical and physical characterization of aerosols using a single particle mass spectrometry based technique University of California eScholarship Repository Summary: Real-...

  16. aerosol retrieval validation: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    off the coast of Chile and Peru, where aerosol-cloud interactions are important to the energy balance (15), and limitations in current observing and modeling capabilities...

  17. aerosol detection equipment: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Daniel, Rosenfeld 464 Mixtures of pollution, dust, sea salt, and volcanic aerosol during ACE-Asia: Radiative properties Energy Storage, Conversion and Utilization Websites...

  18. The Time Evolution of Aerosol Size Distribution Over the Mexico...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Size Distribution Over the Mexico City Plateau. The Time Evolution of Aerosol Size Distribution Over the Mexico City Plateau. Abstract: As part of the MILAGRO field campaign, the...

  19. aerosol mass spectrometry: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    analysis of aerosol organic nitrates with electron ionization high-resolution mass spectrometry MIT - DSpace Summary: Four hydroxynitrates (R(OH)R'ONO2) representative of...

  20. aerosol assisted chemical: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    soluble in water: 2. Isolation of acid, neutral, and basic fractions by modified size Weber, Rodney 5 Simulating Aerosols Using a Chemical Transport Model with Assimilation of...

  1. aerosol particle formation: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1. Introduction 2 Current models tend to under-predict secondary organic aerosol (SOA Weber, Rodney 3 Modeling particle formation during low-pressure silane oxidation: Detailed...

  2. aerosol characterization system: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    soluble in water: 2. Isolation of acid, neutral, and basic fractions by modified size Weber, Rodney 4 Desert dust aerosol age characterized by massage tracking of tracers...

  3. ambient fine aerosols: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    soluble in water: 2. Isolation of acid, neutral, and basic fractions by modified size Weber, Rodney 4 Chemical characterization of the ambient organic aerosol soluble in water:...

  4. aerosol chemical characteristion: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    soluble in water: 2. Isolation of acid, neutral, and basic fractions by modified size Weber, Rodney 5 Simulating Aerosols Using a Chemical Transport Model with Assimilation of...

  5. aerosol characterization experiment: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    soluble in water: 2. Isolation of acid, neutral, and basic fractions by modified size Weber, Rodney 8 Desert dust aerosol age characterized by massage tracking of tracers...

  6. aerosol generation characterization: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    soluble in water: 2. Isolation of acid, neutral, and basic fractions by modified size Weber, Rodney 5 Desert dust aerosol age characterized by massage tracking of tracers...

  7. aerosol monitor development: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Paris May 2003John Matthews Monitoring the Aerosol Phase Function University of New Mexico 12;AstroParticles & Atmosphere, Paris May 2003John Matthews 12;AstroParticles &...

  8. aerosol challenge model: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    climate change is important because of its strong capability in causing extinction of solar radiation. A three-dimensional interactive aerosol-climate model has been used to...

  9. aircraft exhaust aerosol: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Window Location on a King Air 200 Aircraft:aerosol.atmos.und.edu) Objective A Raytheon Beechcraft King Air 200 aircraft has been used to obtain Condensation Particle...

  10. Behavior of aerosols in a steam-air environment

    SciTech Connect (OSTI)

    Adams, R.E.; Tobias, M.L.; Longest, A.W.

    1985-01-01T23:59:59.000Z

    The behavior of aerosols assumed to be characteristic of those generated during light water reactor (LWR) accident sequences and released into containment is being studied in the Nuclear Safety Pilot Plant (NSPP) which is located at the Oak Ridge National Laboratory (ORNL). The program plan for the NSPP aerosol project provides for the study of the behavior, within containment, of simulated LWR accident aerosols emanating from fuel, reactor core structural materials, and from concrete-molten core materials interactions. The aerodynamic behavior of each of these aerosols was studied individually to establish its characteristics; current experiments involve mixtures of these aerosols to establish their interaction and collective behavior within containment. Tests have been conducted with U/sub 3/O/sub 8/ aerosols, Fe/sub 2/O/sub 3/ aerosols, and concrete aerosols in an environment of either dry air (relative humidity (RH) less than 20%) or steam-air (relative humidity (RH) approximately 100%) with aerosol mass concentration being the primary experimental variable.

  11. Influence of moisture on the behavior of aerosols

    SciTech Connect (OSTI)

    Adams, R.E.; Longest, A.W.; Tobias, M.L.

    1986-01-01T23:59:59.000Z

    The behavior of aerosols assumed to be characteristic of those generated during light water reactor (LWR) accident sequences and released into containment has been studied in the Nuclear Safety Pilot Plant (NSPP) located at the Oak Ridge National Laboratory (ORNL). It has been observed that in a saturated steam-air environment a change occurs in the shape of aerosol agglomerates of U/sub 3/O/sub 8/ aerosol, Fe/sub 2/O/sub 3/ aerosol, and mixed U/sub 3/O/sub 8/-Fe/sub 2/O/sub 3/ aerosol from branched-chain to spherical, and that the rate of reduction in the airborne aerosol mass concentration is increased relative to the rate observed in a dry atmosphere. The effect of a steam-air environment on the behavior of concrete aerosol is different. The shape of the agglomerated concrete aerosol is intermediate between branched-chain and spherical and the effect on the rate of reduction in airborne mass concentration appears to be slight. In a related project the shape of an agglomerated Fe/sub 2/O/sub 3/ aerosol was observed to change from branched-chain to spherical at, or near, 100% relative humidity.

  12. LWR aerosol containment experiments (LACE) program and initial test results

    SciTech Connect (OSTI)

    Muhlestein, L.D.; Hilliard, R.K.; Bloom, G.R.; McCormack, J.D.

    1983-11-01T23:59:59.000Z

    Objectives of the test program are to demonstrate, at large-scale, inherent radioactive aerosol retention behavior for postulated high consequence LWR accident situations, and to provide a data base to be used for aerosol behavior and thermal hydraulic computer code validation. The LACE program is being performed in two phases. The first phase is scoping studies of aerosol retention for a containment by pass sequence (Event V). The second phase considers three accident situations where significant inherent aerosol retention could considerably reduce the calculated consequences of the postulated accidents.

  13. Aerosol behavior experiments on light water reactor primary systems

    SciTech Connect (OSTI)

    Rahn, F.J.; Collen, J.; Wright, A.L.

    1988-05-01T23:59:59.000Z

    The results of three experimental programs relevant to the behavior of aerosols in the primary systems of light water reactors (LWRs) are presented. These are the Large-Scale Aerosol Transport Test programs performed at the Marviken test facility in Sweden, parts of the LWR Aerosol Containment Experiments (LACE) performed at the Hanford Engineering Development Laboratory, and the TRAP-MELT validation project performed at Oak Ridge National Laboratory. The Marviken experiments focused on the behavior of aerosols released from fuel and structural materials in a damaged core. Data on the transport of these aerosols and their physical characteristics were obtained in five experiments that simulated LWR primary systems. The LACE program data include results from the containment bypass accident tests, which focused on aerosol transport in pipes. The TRAP-MELT validation project data include results from two types of experiments: (a) aerosol transport tests to investigate aerosol wall plateout in a vertical pipe geometry and (b) aerosol resuspension tests to provide a data base from which analytical models can be developed. Typical results from these programs are presented and discussed.

  14. Iron Speciation and Mixing in Single Aerosol Particles from the...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    iron from atmospheric aerosol is an essential nutrient that can control oceanic productivity, thereby impacting the global carbon budget and climate. Particles collected on...

  15. alkali sulfate aerosol: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    chemical transport model and comparison with observations integrals over the aerosol size distribution when only the lower-order moments of the distribution are known...

  16. aerosol main physical: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Mass light-scattering efficiencies were calculated from both an averaged aerosol size distribution and from distributions modified to reflect the effects of cloud. These...

  17. aerosol monitors including: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    schemes which explicitly simulate the microphysical processes that determine the particle size distribution. These models enable aerosol optical ... Ridley, David Andrew 33...

  18. aerosols nanometriques application: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Mass light-scattering efficiencies were calculated from both an averaged aerosol size distribution and from distributions modified to reflect the effects of cloud. These...

  19. aerosols teresa application: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Mass light-scattering efficiencies were calculated from both an averaged aerosol size distribution and from distributions modified to reflect the effects of cloud. These...

  20. analysis od aerosol: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    closely. The retrieval produces a tighter fit to the RSS data. Climatologies Aerosol size distribution climatology used in GISS GCM does not agree with observations Liu et...

  1. aerosol bolus dispersion: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    a significant scientific risk. Even the optimal altitude of injection and aerosol size distribution are poorly known. Past attention focused on guns and airplanes as means...

  2. acidic sulfate aerosols: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    chemical transport model and comparison with observations integrals over the aerosol size distribution when only the lower-order moments of the distribution are known...

  3. aerosol spray method: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Weber, Rodney 24 Use of in situ cloud condensation nuclei, extinction, and aerosol size distribution measurements to test a method for retrieving cloud Environmental...

  4. atmospheric aerosol emissions: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    gases, and sulfate aerosols are predicted to raise global temperatures via the "greenhouse effect" (IPCC, 1996), growing emissions of SO2Interactions Among Emissions, Atmospheric...

  5. atmospheric aerosols basic: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of atmospheric aerosol. Aplin, KL 2012-01-01 13 1. Introduction The atmospheric greenhouse effect is the basic mechanism Environmental Sciences and Ecology Websites Summary: 1....

  6. Aerosols, Clouds, and Climate Change Stephen E. Schwartz

    E-Print Network [OSTI]

    Schwartz, Stephen E.

    in atmospheric carbon dioxide associated with fossil fuel combustion. Briefly the options are mitigation work has shown instances of large magnitude of aerosol indirect forcing, with local instantaneous

  7. Atmospheric pressure flow reactor / aerosol mass spectrometer studies of tropospheric aerosol nucleat and growth kinetics. Final report, June, 2001

    SciTech Connect (OSTI)

    Worsnop, Douglas R.

    2001-06-01T23:59:59.000Z

    The objective of this program was to determine the mechanisms and rates of growth and transformation and growth processes that control secondary aerosol particles in both the clear and polluted troposphere. The experimental plan coupled an aerosol mass spectrometer (AMS) with a chemical ionization mass spectrometer to provide simultaneous measurement of condensed and particle phases. The first task investigated the kinetics of tropospheric particle growth and transformation by measuring vapor accretion to particles (uptake coefficients, including mass accommodation coefficients and heterogeneous reaction rate coefficients). Other work initiated investigation of aerosol nucleation processes by monitoring the appearance of submicron particles with the AMS as a function of precursor gas concentrations. Three projects were investigated during the program: (1) Ozonolysis of oleic acid aerosols as model of chemical reactivity of secondary organic aerosol; (2) Activation of soot particles by measurement deliquescence in the presence of sulfuric acid and water vapor; (3) Controlled nucleation and growth of sulfuric acid aerosols.

  8. SciTech Connect: Results and code predictions for ABCOVE aerosol...

    Office of Scientific and Technical Information (OSTI)

    Results and code predictions for ABCOVE aerosol code validation - Test AB5 Citation Details In-Document Search Title: Results and code predictions for ABCOVE aerosol code...

  9. E-Print Network 3.0 - aerosol load study Sample Search Results

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    conditions... reserved. Keywords: India; Aerosol loading; Aerosol forcing; MODIS; TOMS; Remote sensing 1. Introduction... heating effect on the earth surface and in turn...

  10. E-Print Network 3.0 - aerosol robotic network Sample Search Results

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ), AERONET--A federated instrument network and data archive for aerosol characterization, Remote Sens... Period examining aerosol properties and radiative ... Source: Brookhaven...

  11. aerosol source-receptor relationships: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ON CCN CONCENTRATION AND AEROSOL FIRST INDIRECT RADIATIVE composition, aerosol size distribution is the more dominant parameter on CCN activation Feingold, GRL 2003;...

  12. Characterization of ambient aerosol composition and formation mechanisms and development of quantification methodologies utilizing ATOFMS

    E-Print Network [OSTI]

    Qin, Xueying

    2007-01-01T23:59:59.000Z

    cloud coverage as a consequence of aerosol heating effect after absorbing solar radiation.effects of aerosols can cause cooling since clouds reflect the incoming solar radiation

  13. Thermal chemistry and photochemistry of hexafluoroacetone on...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    chemistry and photochemistry of hexafluoroacetone on rutile TiO2(110) . Thermal chemistry and photochemistry of hexafluoroacetone on rutile TiO2(110) . Abstract: The ultraviolet...

  14. Capturing Chemistry in XML/CML

    E-Print Network [OSTI]

    Townsend, Joseph A; Adams, Sam; Goodman, Jonathan M; Murray-Rust, Peter; Waudby, Chris A

    Chemical Markup Language (CML) is an XML-conformant Schema that describes molecules, spectra, reactions, and computational chemistry. It is capable of capturing the chemistry in a variety of current publications and is becoming adopted by many...

  15. TROPOSPHERIC AEROSOL PROGRAM, PROGRAM PLAN, MARCH 2001

    SciTech Connect (OSTI)

    SCHWARTZ,S.E.; LUNN,P.

    2001-03-01T23:59:59.000Z

    The goal of Tropospheric Aerosol Program (TAP) will be to develop the fundamental scientific understanding required to construct tools for simulating the life cycle of tropospheric aerosols--the processes controlling their mass loading, composition, and microphysical properties, all as a function of time, location, and altitude. The TAP approach to achieving this goal will be by conducting closely linked field, modeling, laboratory, and theoretical studies focused on the processes controlling formation, growth, transport, and deposition of tropospheric aerosols. This understanding will be represented in models suitable for describing these processes on a variety of geographical scales; evaluation of these models will be a key component of TAP field activities. In carrying out these tasks TAP will work closely with other programs in DOE and in other Federal and state agencies, and with the private sector. A forum to directly work with our counterparts in industry to ensure that the results of this research are translated into products that are useful to that community will be provided by NARSTO (formerly the North American Research Strategy on Tropospheric Ozone), a public/private partnership, whose membership spans government, the utilities, industry, and university researchers in Mexico, the US, and Canada.

  16. User Manual Frick Chemistry Laboratory

    E-Print Network [OSTI]

    Torquato, Salvatore

    the atrium connects the laboratory wing with the administrative offices. This provides a light-filled space to make the new Frick Chemistry Laboratory (and the surrounding natural sciences neighborhood) one technologies that reduce energy demand and con- serve water. The design and construction teams have implemented

  17. Theoretical Chemistry Theory, Computation, and

    E-Print Network [OSTI]

    Gherman, Benjamin F.

    1 23 Theoretical Chemistry Accounts Theory, Computation, and Modeling ISSN 1432-881X Volume 128). In order to explore the origin of this preference, density functional theory (DFT) calculations have been-terminus of nascent eubacterial proteins during protein synthesis [1­4]. As PDF is essential for bacterial survival

  18. Interfacial Chemistry and Engineering Annual Report 2000

    SciTech Connect (OSTI)

    Grate, Jay W.

    2001-08-01T23:59:59.000Z

    This annual report describes the research and staff accomplishments in 2000 for the EMSL Interfacial Chemistry and Engineering Directorate.

  19. Eleventh international symposium on radiopharmaceutical chemistry

    SciTech Connect (OSTI)

    NONE

    1995-12-31T23:59:59.000Z

    This document contains abstracts of papers which were presented at the Eleventh International Symposium on Radiopharmaceutical Chemistry. Sessions included: radiopharmaceuticals for the dopaminergic system, strategies for the production and use of labelled reactive small molecules, radiopharmaceuticals for measuring metabolism, radiopharmaceuticals for the serotonin and sigma receptor systems, labelled probes for molecular biology applications, radiopharmaceuticals for receptor systems, radiopharmaceuticals utilizing coordination chemistry, radiolabelled antibodies, radiolabelling methods for small molecules, analytical techniques in radiopharmaceutical chemistry, and analytical techniques in radiopharmaceutical chemistry.

  20. Technetium Chemistry Science Challenges in Environmental Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Technetium Chemistry Science Challenges in Environmental Science and Waste Processing Workshop Sponsored by Environmental Molecular Science Laboratory Richland, Washington July...