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1

ARM Aerosol Working Group Meeting  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)Productssondeadjustsondeadjust Documentation DataProductswsicloudwsicloudsummarygifAOS ProcessingReport

2

ARM Aerosol Working Group Meeting  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)Productssondeadjustsondeadjust Documentation DataProductswsicloudwsicloudsummarygifAOS ProcessingReport

3

Aerosol Working Group Contributions Accomplishments for 2006  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout the BuildingInnovation 2011 Simulation StudiesAerosol

4

Construction work process management  

E-Print Network [OSTI]

-related activities. The study addresses relationships between selected TQM concepts (TQM tools, training, process focus, and teamwork) and work process management, defined in terms of planning, control, and improvement. The investigation was performed in two...

Soares, Jorge Barbosa

1994-01-01T23:59:59.000Z

5

A simplified model of aerosol removal by natural processes in reactor containments  

SciTech Connect (OSTI)

Simplified formulae are developed for estimating the aerosol decontamination that can be achieved by natural processes in the containments of pressurized water reactors and in the drywells of boiling water reactors under severe accident conditions. These simplified formulae were derived by correlation of results of Monte Carlo uncertainty analyses of detailed models of aerosol behavior under accident conditions. Monte Carlo uncertainty analyses of decontamination by natural aerosol processes are reported for 1,000, 2,000, 3,000, and 4,000 MW(th) pressurized water reactors and for 1,500, 2,500, and 3,500 MW(th) boiling water reactors. Uncertainty distributions for the decontamination factors and decontamination coefficients as functions of time were developed in the Monte Carlo analyses by considering uncertainties in aerosol processes, material properties, reactor geometry and severe accident progression. Phenomenological uncertainties examined in this work included uncertainties in aerosol coagulation by gravitational collision, Brownian diffusion, turbulent diffusion and turbulent inertia. Uncertainties in aerosol deposition by gravitational settling, thermophoresis, diffusiophoresis, and turbulent diffusion were examined. Electrostatic charging of aerosol particles in severe accidents is discussed. Such charging could affect both the coagulation and deposition of aerosol particles. Electrostatic effects are not considered in most available models of aerosol behavior during severe accidents and cause uncertainties in predicted natural decontamination processes that could not be taken in to account in this work. Median (50%), 90 and 10% values of the uncertainty distributions for effective decontamination coefficients were correlated with time and reactor thermal power. These correlations constitute a simplified model that can be used to estimate the decontamination by natural aerosol processes at 3 levels of conservatism. Applications of the model are described.

Powers, D.A.; Washington, K.E.; Sprung, J.L. [Sandia National Labs., Albuquerque, NM (United States); Burson, S.B. [Nuclear Regulatory Commission, Washington, DC (United States)

1996-07-01T23:59:59.000Z

6

The Aerosol Modeling Testbed: A community tool to objectively evaluate aerosol process modules  

SciTech Connect (OSTI)

This study describes a new modeling paradigm that significantly advances how the third activity is conducted while also fully exploiting data and findings from the first two activities. The Aerosol Modeling Testbed (AMT) is a computational framework for the atmospheric sciences community that streamlines the process of testing and evaluating aerosol process modules over a wide range of spatial and temporal scales. The AMT consists of a fully-coupled meteorology-chemistry-aerosol model, and a suite of tools to evaluate the performance of aerosol process modules via comparison with a wide range of field measurements. The philosophy of the AMT is to systematically and objectively evaluate aerosol process modules over local to regional spatial scales that are compatible with most field campaigns measurement strategies. The performance of new treatments can then be quantified and compared to existing treatments before they are incorporated into regional and global climate models. Since the AMT is a community tool, it also provides a means of enhancing collaboration and coordination among aerosol modelers.

Fast, Jerome D.; Gustafson, William I.; Chapman, Elaine G.; Easter, Richard C.; Rishel, Jeremy P.; Zaveri, Rahul A.; Grell, Georg; Barth, Mary

2011-03-02T23:59:59.000Z

7

Representing Cloud Processing of Aerosol in Numerical Models  

SciTech Connect (OSTI)

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.

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

2005-03-18T23:59:59.000Z

8

Solar thermal aerosol flow reaction process  

DOE Patents [OSTI]

The present invention provides an environmentally beneficial process using concentrated sunlight to heat radiation absorbing particles to carry out highly endothermic gas phase chemical reactions ultimately resulting in the production of hydrogen or hydrogen synthesis gases.

Weimer, Alan W.; Dahl, Jaimee K.; Pitts, J. Roland; Lewandowski, Allan A.; Bingham, Carl; Tamburini, Joseph R.

2005-03-29T23:59:59.000Z

9

Atmospheric Science Program Cumulus Humilis Aerosol Processing Study (CHAPS)  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAboutScience Program Cumulus Humilis Aerosol Processing Study (CHAPS)

10

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...

11

WRAP process area development control work plan  

SciTech Connect (OSTI)

This work plan defines the manner in which the Waste Receiving and Processing Facility, Module I Process Area will be maintained under development control status. This status permits resolution of identified design discrepancies, control system changes, as-building of equipment, and perform modifications to increase process operability and maintainability as parallel efforts. This work plan maintains configuration control as these efforts are undertaken. This task will end with system testing and reissue of field verified design drawings.

Leist, K.L., Fluor Daniel Hanford

1997-02-27T23:59:59.000Z

12

Laboratory Studies of Processing of Carbonaceous Aerosols by Atmospheric Oxidants/Hygroscopicity and CCN Activity of Secondary & Processed Primary Organic Aerosols  

SciTech Connect (OSTI)

The atmosphere is composed of a complex mixture of gases and suspended microscopic aerosol particles. The ability of these particles to take up water (hygroscopicity) and to act as nuclei for cloud droplet formation significantly impacts aerosol light scattering and absorption, and cloud formation, thereby influencing air quality, visibility, and climate in important ways. A substantial, yet poorly characterized component of the atmospheric aerosol is organic matter. Its major sources are direct emissions from combustion processes, which are referred to as primary organic aerosol (POA), or in situ processes in which volatile organic compounds (VOCs) are oxidized in the atmosphere to low volatility reaction products that subsequent condense to form particles that are referred to as secondary organic aerosol (SOA). POA and VOCs are emitted to the atmosphere from both anthropogenic and natural (biogenic) sources. The overall goal of this experimental research project was to conduct laboratory studies under simulated atmospheric conditions to investigate the effects of the chemical composition of organic aerosol particles on their hygroscopicity and cloud condensation nucleation (CCN) activity, in order to develop quantitative relationships that could be used to more accurately incorporate aerosol-cloud interactions into regional and global atmospheric models. More specifically, the project aimed to determine the products, mechanisms, and rates of chemical reactions involved in the processing of organic aerosol particles by atmospheric oxidants and to investigate the relationships between the chemical composition of organic particles (as represented by molecule sizes and the specific functional groups that are present) and the hygroscopicity and CCN activity of oxidized POA and SOA formed from the oxidation of the major classes of anthropogenic and biogenic VOCs that are emitted to the atmosphere, as well as model hydrocarbons. The general approach for this project was to carry out reactions of representative anthropogenic and biogenic VOCs and organic particles with ozone (O3), and hydroxyl (OH), nitrate (NO3), and chlorine (Cl) radicals, which are the major atmospheric oxidants, under simulated atmospheric conditions in large-volume environmental chambers. A combination of on-line and off-line analytical techniques were used to monitor the chemical and physical properties of the particles including their hygroscopicity and CCN activity. The results of the studies were used to (1) improve scientific understanding of the relationships between the chemical composition of organic particles and their hygroscopicity and CCN activity, (2) develop an improved molecular level theoretical framework for describing these relationships, and (3) establish a large database that is being used to develop parameterizations relating organic aerosol chemical properties and SOA sources to particle hygroscopicity and CCN activity for use in regional and global atmospheric air quality and climate models.

Ziemann, P.J.; Arey, J.; Atkinson, R.; Kreidenweis, S.M.; Petters, M.D.

2012-06-13T23:59:59.000Z

13

Electrostatics and radioactive aerosol behavior  

SciTech Connect (OSTI)

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.

Clement, C.F.

1994-12-31T23:59:59.000Z

14

The importance of aerosol composition and mixing state on predicted CCN concentration and the variation of the importance with atmospheric processing of aerosol  

SciTech Connect (OSTI)

The influences of atmospheric aerosols on cloud properties (i.e., aerosol indirect effects) strongly depend on the aerosol CCN concentrations, which can be effectively predicted from detailed aerosol size distribution, mixing state, and chemical composition using Köhler theory. However, atmospheric aerosols are complex and heterogeneous mixtures of a large number of species that cannot be individually simulated in global or regional models due to computational constraints. Furthermore, the thermodynamic properties or even the molecular identities of many organic species present in ambient aerosols are often not known to predict their cloud-activation behavior using Köhler theory. As a result, simplified presentations of aerosol composition and mixing state are necessary for large-scale models. In this study, aerosol microphysics, CCN concentrations, and chemical composition measured at the T0 urban super-site in Mexico City during MILAGRO are analyzed. During the campaign in March 2006, aerosol size distribution and composition often showed strong diurnal variation as a result of both primary emissions and aging of aerosols through coagulation and local photochemical production of secondary aerosol species. The submicron aerosol composition was ~1/2 organic species. Closure analysis is first carried out by comparing CCN concentrations calculated from the measured aerosol size distribution, mixing state, and chemical composition using extended Köhler theory to concurrent CCN measurements at five supersaturations ranging from 0.11% to 0.35%. The closure agreement and its diurnal variation are studied. CCN concentrations are also derived using various simplifications of the measured aerosol mixing state and chemical composition. The biases associated with these simplifications are compared for different supersaturations, and the variation of the biases is examined as a function of aerosol age. The results show that the simplification of internally mixed, size-independent particle composition leads to substantial overestimation of CCN concentration for freshly emitted aerosols in early morning, but can reasonably predict the CCN concentration after the aerosols underwent atmospheric processing for several hours. This analysis employing various simplifications provides insights into the essential information of particle chemical composition that needs to be represented in models to adequately predict CCN concentration and cloud microphysics.

Wang, J.; Cubison, M.; Aiken, A.; Jimenez, J.; Collins, D.; Gaffney, J.; Marley, N.

2010-03-15T23:59:59.000Z

15

Memorandum, NNSA Activity Level Work Planning & Control Processes...  

Broader source: Energy.gov (indexed) [DOE]

NNSA Activity Level Work Planning & Control Processes, January 2006 Memorandum, NNSA Activity Level Work Planning & Control Processes, January 2006 January 23, 2006 Memorandum from...

16

Clean Energy Works Portland Pilot Process Evaluation | Department...  

Broader source: Energy.gov (indexed) [DOE]

Energy Works Portland Pilot Process Evaluation Clean Energy Works Portland Pilot Process Evaluation This is a document from Research Into Action Inc., posted to the website of the...

17

Photolytic processing of secondary organic aerosols dissolved in cloud droplets  

SciTech Connect (OSTI)

The effect of UV irradiation on the molecular composition of aqueous extracts of secondary organic aerosol (SOA) was investigated. SOA was prepared by the dark reaction of ozone and d-limonene at 0.05 - 1 ppm precursor concentrations and collected with a particle-into-liquid sampler (PILS). The PILS extracts were photolyzed by 300 - 400 nm radiation for up to 24 hours. Water-soluble SOA constituents were analyzed using high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) at different stages of photolysis for all SOA precursor concentrations. Exposure to UV radiation increased the average O/C ratio and decreased the average double bond equivalent (DBE) of the dissolved SOA compounds. Oligomeric compounds were significantly reduced by photolysis relative to the monomeric compounds. Direct pH measurements showed that compounds containing carboxylic acids increased upon photolysis. Methanol reactivity analysis revealed significant photodissociation of molecules containing carbonyl groups and formation of carboxylic acids. Aldehydes, such as limononaldehyde, were almost completely removed. The removal of carbonylswas confirmed by the UV-Vis absorption spectroscopy of the SOA extracts where the absorbance in the carbonyl n??* band decreased significantly upon photolysis. The effective quantum yield (the number of carbonyls destroyed per photon absorbed) was estimated as ~ 0.03. The concentration of peroxides did not change significantly during photolysis as quantified with an iodometric test. Although organic peroxides were photolyzed, the likely end products of photolysis were smaller peroxides, including hydrogen peroxide, resulting in a no net change in the peroxide content.

Bateman, Adam P.; Nizkorodov, Serguei; Laskin, Julia; Laskin, Alexander

2011-05-26T23:59:59.000Z

18

ARM AOS Processing Status and Aerosol Intensive Properties VAP  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)Productssondeadjustsondeadjust Documentation DataProductswsicloudwsicloudsummarygifAOS Processing Status

19

Work as coordination and coordination as work: A process perspective on FLOSS development projects  

E-Print Network [OSTI]

and coordination as work: A process perspective on FLOSS development projects Abstract Coordination in work teamsWork as coordination and coordination as work: A process perspective on FLOSS development projects Dipartimento Impresa e Lavoro UniversitĂ  degli Studi di Cassino Cassino Italy #12;Work as coordination

Crowston, Kevin

20

Laboratory Investigation of Contact Freezing and the Aerosol to Ice Crystal Transformation Process  

SciTech Connect (OSTI)

This project has been focused on the following objectives: 1. Investigations of the physical processes governing immersion versus contact nucleation, specifically surface-induced crystallization; 2. Development of a quadrupole particle trap with full thermodynamic control over the temperature range 0 to –40 °C and precisely controlled water vapor saturation ratios for continuous, single-particle measurement of the aerosol to ice crystal transformation process for realistic ice nuclei; 3. Understanding the role of ice nucleation in determining the microphysical properties of mixed-phase clouds, within a framework that allows bridging between laboratory and field measurements.

Shaw, Raymond A. [Michigan Technological University

2014-10-28T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Work Structuring to Achieve Integrated ProductProcess Design  

E-Print Network [OSTI]

Work Structuring to Achieve Integrated Product­Process Design Cynthia C. Y. Tsao, A.M.ASCE1 ; Iris presents "work structuring," a term used to describe the effort of integrating product and process design. As the project progresses, work structuring becomes more focused to guide the design and execution of interacting

Tommelein, Iris D.

22

A numerical simulation of atmospheric photochemical processes including interactions with aerosol particles  

SciTech Connect (OSTI)

We propose a comprehensive model of atmospheric photochemical processes that can be used to investigate the interactions between gas species and aerosol particles. We considered both gas and particle phase reactions, transport of material between these phases, convection, turbulent diffusion, particle growth, coagulation, nucleation, and sources. The aerosol particle phase is not forced to follow the gas phase in equilibrium; transport to the particles is described by diffusion to the particle surface. The resulting model treats 33 gas phase species and 39 particles phase species; 16 of these are transported between the phases. The particle size distribution is approximated by 9 sections between 0.01 and 10 {mu}m diameter. Strong interactions between the gas and particles are seen. Higher relative humidity results in more particle volume and surface area, allowing the interphase transport to become competitive with the reaction terms. In particular, at high relative humidities the increased scavenging of HO{sub 2} radicals by particles reduces the O{sub 3} maximum concentration. This effect is seen only on days when the maximum relative humidity exceeds 90%. This conclusion has implications for the applicability of models developed for the Los Angeles Basin, where the maximum relative humidity rarely exceeds 75%, to more humid climates like Houston.

Hackler, M.A.

1989-01-01T23:59:59.000Z

23

Hot Work Procedures The Hot Work reviewing process is established to prevent ignition of combustible and  

E-Print Network [OSTI]

Hot Work Procedures Purpose The Hot Work reviewing process is established to prevent ignition requirements when applicable: · Within 35 feet of work: o Remove combustible/flammable materials, dust, lint Eliminate explosive atmosphere. o Cover fixed combustibles with fire resistive covers, guards, or shields. o

de Lijser, Peter

24

AEROSOL, CLOUDS, AND CLIMATE CHANGE  

SciTech Connect (OSTI)

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.

SCHWARTZ, S.E.

2005-09-01T23:59:59.000Z

25

Atmospheric pressure flow reactor / aerosol mass spectrometer studies of tropospheric aerosol nucleat and growth kinetics. Final report, June, 2001  

SciTech Connect (OSTI)

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.

Worsnop, Douglas R.

2001-06-01T23:59:59.000Z

26

Electrospray neutralization process and apparatus for generation of nano-aerosol and nano-structured materials  

DOE Patents [OSTI]

The claimed invention describes methods and apparatuses for manufacturing nano-aerosols and nano-structured materials based on the neutralization of charged electrosprayed products with oppositely charged electrosprayed products. Electrosprayed products include molecular ions, nano-clusters and nano-fibers. Nano-aerosols can be generated when neutralization occurs in the gas phase. Neutralization of electrospan nano-fibers with molecular ions and charged nano-clusters may result in the formation of fibrous aerosols or free nano-mats. Nano-mats can also be produced on a suitable substrate, forming efficient nano-filters.

Bailey, Charles L. (Cross Junction, VA); Morozov, Victor (Manassas, VA); Vsevolodov, Nikolai N. (Kensington, MD)

2010-08-17T23:59:59.000Z

27

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

E-Print Network [OSTI]

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 ...

Johnson, Kirsten S. (Kirsten Sue)

2008-01-01T23:59:59.000Z

28

Process-model Simulations of Cloud Albedo Enhancement by Aerosols in the Arctic  

SciTech Connect (OSTI)

A cloud-resolving model is used to simulate the effectiveness of Arctic marine cloud brightening via injection of cloud condensation nuclei (CCN). An updated cloud microphysical scheme is employed, with prognostic CCN and cloud particle numbers in both liquid and mixed-phase marine low clouds. Injection of CCN into the marine boundary layer can delay the collapse of the boundary layer and increase low-cloud albedo. Because nearly all of the albedo effects are in the liquid phase due to the removal of ice water by snowfall when ice processes are involved, albedo increases are stronger for pure liquid clouds than mixed-phase clouds. Liquid precipitation can be suppressed by CCN injection, whereas ice precipitation (snow) is affected less; thus the effectiveness of brightening mixed-phase clouds is lower than for liquid-only clouds. CCN injection into a clean regime results in a greater albedo increase than injection into a polluted regime, consistent with current knowledge about aerosol-cloud interactions. Unlike previous studies investigating warm clouds, dynamical changes in circulation due to precipitation changes are small.

Kravitz, Benjamin S.; Wang, Hailong; Rasch, Philip J.; Morrison, H.; Solomon, Amy

2014-11-17T23:59:59.000Z

29

A project management focused framework for assuring quality work processes  

SciTech Connect (OSTI)

Federal Manufacturing & Technologies/New Mexico (FM&T/NM) of AlliedSignal is an organization of approximately 300 associates providing operations support, engineering, and other technical services for DOE, New Mexico`s National Laboratories, etc. Work performed is primarily project-oriented and ranges from executing a major long-term contract for retrofitting and maintaining a large fleet of escort vehicles to creating a single, small, prototype electronic device for measuring radiation in a unique environment. FM&T/NM is functionally organized and operates in a classic matrix format with functional departments providing personnel with technical expertise, necessary physical resources, and administrative support to several project-based groups. Like most matrix-based organizations that provide support to diverse customers, FM&T/NM has encountered problems that occur when a group of project managers is expected to work together in using and scheduling a shared set of limited resources for the good of the organization as a whole. The framework for managing projects that we present focuses on developing, understanding, and managing the relationships between the functional organization structure, the system of work processes, and the management of projects. FM&T/NM retains its functional structure which primarily assigns personnel to work processes. The evolving role of the process leader focuses primarily on designing, managing, and improving the process, and the interactions among the subprocesses. The project manager is responsible for (1) translating customer requirements into product specifications, (2) determining the sequence of activities needed to meet project goals, (3) scheduling the required work processes, (4) monitoring project progress, (5) providing liaison between the customer and process leaders, and (6) having the desired product and/or service delivered to a satisfied customer in a timely manner.

Gamsby, S.O.; Mize, J.D. [Allied Signal, Inc., Albuquerque, NM (United States). Federal Mfg. and Technologies; Reid, R.A. [New Mexico Univ., Albuquerque, NM (United States)

1996-10-01T23:59:59.000Z

30

PROCESS ANALYSIS WORK FOR THE DOE HYDROGEN PROGRAM -2001  

E-Print Network [OSTI]

. Mann National Renewable Energy Laboratory Golden, CO 80401 Abstract In 2001, process analysis work conducted at the National Renewable Energy Laboratory for the Department of Energy's Hydrogen Program, and 3) assessment of the mass production of carbon nanotubes. The first study covers a project

31

Irreversible work and inner friction in quantum thermodynamic processes  

E-Print Network [OSTI]

We discuss the thermodynamics of closed quantum systems driven out of equilibrium by a change in a control parameter and undergoing a unitary process. We compare the work actually done on the system with the one that would be performed along ideal adiabatic and isothermal transformations. The comparison with the latter leads to the introduction of irreversible work, while that with the former leads to the introduction of inner friction. We show that these two quantities can be treated on equal footing, as both can be linked with the heat exchanged in thermalization processes and both can be expressed as relative entropies. Furthermore, we show that a specific fluctuation relation for the entropy production associated with the inner friction exists, which allows the inner friction to be written in terms of its cumulants.

F. Plastina; A. Alecce; T. J. G. Apollaro; G. Falcone; G. Francica; F. Galve; N. Lo Gullo; R. Zambrini

2014-07-13T23:59:59.000Z

32

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

SciTech Connect (OSTI)

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

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

2013-02-13T23:59:59.000Z

33

NREL: Process Development and Integration Laboratory - Working with Us  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the Contributions and AchievementsResearchReliabilityand7Working with Us The Process

34

aerosols | EMSL  

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

aerosols aerosols Leads No leads are available at this time. Magnesium behavior and structural defects in Mg+ ion implanted silicon carbide. Abstract: As a candidate material for...

35

5, 79658026, 2005 Simulating aerosol  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

36

Continuous air monitor for alpha-emitting aerosol particles  

SciTech Connect (OSTI)

A new alpha Continuous Air Monitor (CAM) sampler is being developed for use in detecting the presence of alpha-emitting aerosol particles. The effort involves design, fabrication and evaluation of systems for the collection of aerosol and for the processing of data to speciate and quantify the alpha emitters of interest. At the present time we have a prototype of the aerosol sampling system and we have performed wind tunnel tests to characterize the performance of the device for different particle sizes, wind speeds, flow rates and internal design parameters. The results presented herein deal with the aerosol sampling aspects of the new CAM sampler. Work on the data processing, display and alarm functions is being done in parallel with the particle sampling work and will be reported separately at a later date. 17 refs., 5 figs., 3 tabs.

McFarland, A.R.; Ortiz, C.A. (Texas A and M Univ., College Station, TX (USA). Dept. of Mechanical Engineering); Rodgers, J.C.; Nelson, D.C. (Los Alamos National Lab., NM (USA))

1990-01-01T23:59:59.000Z

37

COLLABORATIVE RESEARCH: Study of Aerosol Sources and Processing at the GVAX Pantnagar Supersite  

SciTech Connect (OSTI)

This project funded the participation of scientists from seven research groups, running more than thirty instruments, in the Winter Intensive Operating Period (January-February 2012) of the Clean Air for London (ClearfLo) campaign at a rural site in Detling, UK, 45 km southeast of central London. The primary science questions for the ClearfLo Winter IOP were, 1) what is the urban increment of particulate matter (PM) and other pollutants in the greater London area, and, 2) what is the contribution of solid fuel use for home heating to wintertime PM? An additional motivation for the Detling measurements was the question of whether coatings on black carbon particles enhance absorption. The following four key accomplishments have been identified so far: 1) Chemical, physical and optical characterization of PM from local and regional sources (Figures 2, 4, 5 and 6). 2) Measurement of urban increment in particulate matter and gases in London (Figure 3). 3) Measurement of optical properties and chemical composition of coatings on black carbon containing particles indicates absorption enhancement. 4) First deployment of chemical ionization instrument (MOVI-CI-TOFMS) to measure both particle-phase and gas-phase organic acids. (See final report from Joel Thornton, University of Washington, for details.) Analysis of the large dataset acquired in Detling is ongoing and will yield further key accomplishments. These measurements of urban and rural aerosol properties will contribute to improved modeling of regional aerosol emissions, and of atmospheric aging and removal. The measurement of absorption enhancement by coatings on black carbon will contribute to improved modeling of the direct radiative properties of PM.

Worsnop, Douglas R. [Principal Investigator

2014-07-28T23:59:59.000Z

38

Operational efficiency through resource planning optimization and work process improvement  

E-Print Network [OSTI]

This thesis covers work done at National Grid to improve resource planning and the execution of pipeline construction and maintenance work carried out at the yards. Resource Planning, the art of picking the right jobs for ...

Balwani, Siddharth (Siddharth Vashdev)

2012-01-01T23:59:59.000Z

39

Reimbursable Work For Non-Federal Sponsors Process Manual  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

This Manual provides detailed requirements to supplement DOE O 481.1A, Work for Others (Non-DOE Funded Work), dated 01-03-01, which establishes requirements for the performance of work for non-Department of Energy (DOE) National Nuclear Security Administration (NNSA) entities by DOE/NNSA/contractor personnel and/or the use of DOE facilities that is not directly funded by DOE/NNSA appropriations. (Cancels DOE M 481.1-1).

2001-01-03T23:59:59.000Z

40

12010-10-21 ESDSWG -Technolgy Infusion Working Group Technology Infusion Process  

E-Print Network [OSTI]

12010-10-21 ESDSWG - Technolgy Infusion Working Group Technology Infusion Process Steve Olding 9th Infusion Working Group Technology Infusion Process 2009 Stakeholder needs identification Science needs End technologies Candidate technologies Known infusion barriers Infusion planning Technology matching Identified

Christian, Eric

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Aerosol engineering: design and stability of aerosol reactors  

SciTech Connect (OSTI)

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.

Pratsinis, S.E.

1985-01-01T23:59:59.000Z

42

Reimbursable Work For Non-Federal Sponsors Process Manual  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

This Manual provides detailed requirements to supplement DOE O 481.1B, Work For Others (Non-Department of Energy Funded Work), dated 9-28-01, which establishes requirements for the performance of work for non-Department of Energy (DOE)/non-National Nuclear Security Administration (NNSA) entities by DOE/NNSA/contractor personnel and/or the use of DOE/NNSA facilities that is not directly funded by DOE/NNSA appropriations. Chg 1, dated 9-28-01. Cancels DOE M 481.1-1. Certified 12-28-06.

2001-01-03T23:59:59.000Z

43

Revised process for work zone decision-making based on quantitative performance measures  

E-Print Network [OSTI]

importantly, the revised decision-making process incorporates a feedback loop. Quantitative data collected in work zones is analyzed after the work zone is complete, to determine the impacts specific decisions had on mobility in the work zone. The lessons...

Hartmann, Thomas Wayne

2008-10-10T23:59:59.000Z

44

Development of a robust work transfer iomplementation process  

E-Print Network [OSTI]

The industry-wide need for a robust method of transferring the manufacturing of a component from one location to another is addressed in this thesis. Work transfer activities can be initiated due to a number of business ...

Murdoch, Kimberly R

2004-01-01T23:59:59.000Z

45

Use of the ARM Measurements of Spectral Zenith Radiance for Better Understanding of 3D Cloud-Radiation Processes & Aerosol-Cloud Interaction  

SciTech Connect (OSTI)

We proposed a variety of tasks centered on the following question: what can we learn about 3D cloud-radiation processes and aerosol-cloud interaction from rapid-sampling ARM measurements of spectral zenith radiance? These ARM measurements offer spectacular new and largely unexploited capabilities in both the temporal and spectral domains. Unlike most other ARM instruments, which average over many seconds or take samples many seconds apart, the new spectral zenith radiance measurements are fast enough to resolve natural time scales of cloud change and cloud boundaries as well as the transition zone between cloudy and clear areas. In the case of the shortwave spectrometer, the measurements offer high time resolution and high spectral resolution, allowing new discovery-oriented science which we intend to pursue vigorously. Research objectives are, for convenience, grouped under three themes: â?˘ Understand radiative signature of the transition zone between cloud-free and cloudy areas using data from ARM shortwave radiometers, which has major climatic consequences in both aerosol direct and indirect effect studies. â?˘ Provide cloud property retrievals from the ARM sites and the ARM Mobile Facility for studies of aerosol-cloud interactions. â?˘ Assess impact of 3D cloud structures on aerosol properties using passive and active remote sensing techniques from both ARM and satellite measurements.

Alexander Marshak; Warren Wiscombe; Yuri Knyazikhin; Christine Chiu

2011-05-24T23:59:59.000Z

46

Aerosol Cans? -Aerosol cans use a pressurized  

E-Print Network [OSTI]

? - The waste generated in the processing of images/photos contains silver. Silver is a toxic heavy metal the product. Propellants are often flammable and/or toxic. Therefore, never store aerosol cans near ignition of this pamphlet. -Carefully transfer the old paint thinner from the one gallon closable can to the 30 gallon metal

Jia, Songtao

47

Assessing the Effects of Anthropogenic Aerosols on Pacific Storm Track Using a Multiscale Global Climate Model  

SciTech Connect (OSTI)

Atmospheric aerosols impact weather and global general circulation by modifying cloud and precipitation processes, but the magnitude of cloud adjustment by aerosols remains poorly quantified and represents the largest uncertainty in estimated forcing of climate change. Here we assess the impacts of anthropogenic aerosols on the Pacific storm track using a multi-scale global aerosol-climate model (GCM). Simulations of two aerosol scenarios corresponding to the present day and pre-industrial conditions reveal long-range transport of anthropogenic aerosols across the north Pacific and large resulting changes in the aerosol optical depth, cloud droplet number concentration, and cloud and ice water paths. Shortwave and longwave cloud radiative forcing at the top of atmosphere are changed by - 2.5 and + 1.3 W m-2, respectively, by emission changes from pre-industrial to present day, and an increased cloud-top height indicates invigorated mid-latitude cyclones. The overall increased precipitation and poleward heat transport reflect intensification of the Pacific storm track by anthropogenic aerosols. Hence, this work provides for the first time a global perspective of the impacts of Asian pollution outflows from GCMs. Furthermore, our results suggest that the multi-scale modeling framework is essential in producing the aerosol invigoration effect of deep convective clouds on the global scale.

Wang, Yuan; Wang, Minghuai; Zhang, Renyi; Ghan, Steven J.; Lin, Yun; Hu, Jiaxi; Pan, Bowen; Levy, Misti; Jiang, Jonathan; Molina, Mario J.

2014-05-13T23:59:59.000Z

48

EMSL - aerosols  

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

aerosols en Magnesium behavior and structural defects in Mg+ ion implanted silicon carbide. http:www.emsl.pnl.govemslwebpublicationsmagnesium-behavior-and-structural-defects-m...

49

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

SciTech Connect (OSTI)

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.

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

50

6, 75197562, 2006 Simulating aerosol  

E-Print Network [OSTI]

, 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

Paris-Sud XI, Université de

51

Modal Bin Hybrid Model: A Surface Area Consistent, Triple Moment Sectional Method for Use in Process-oriented Modeling of Atmospheric Aerosols  

SciTech Connect (OSTI)

A triple moment sectional method, Modal Bin Hybrid Model (MBHM), has been developed. In addition to number and mass (volume), surface area is predicted (and preserved), which is important for gas-to-particle mass transfer and light extinction cross section. The performance of MBHM was evaluated against double moment sectional (DMS) methods with various size resolutions up to BIN256 (BINx: x is number of sections over three orders of magnitude in size, ?logD = 3/x) for simulating evolution of particles under simultaneously occurring nucleation, condensation and coagulation processes. Because MBHM gives a physically consistent form of the intra-sectional distributions, errors and biases of MBHM at BIN4-8 resolution were almost equivalent to those of DMS at BIN16-32 resolution for various important variables such as the moments Mk (k: 0, 2, 3), dMk/dt, and the number and volume of particles larger than a certain diameter. Another important feature of MBHM is that only a single bin is adequate to simulate full aerosol dynamics for particles whose size distribution can be approximated by a single lognormal mode. This flexibility is useful for process-oriented (multi category and/or mixing state) modeling: primary aerosols whose size parameters would not differ substantially in time and space can be expressed by a single or a small number of modes, whereas secondary aerosols whose size changes drastically from one to several hundred nanometers can be expressed by a number of modes. Added dimensions can be applied to MBHM to represent mixing state or photo-chemical age for aerosol mixing state studies.

Kajino, Mizuo; Easter, Richard C.; Ghan, Steven J.

2013-09-10T23:59:59.000Z

52

Proficiency and working memory based explanations for nonnative speakers’ sensitivity to agreement in sentence processing  

E-Print Network [OSTI]

This study examines the roles of proficiency and working memory (WM) capacity in second-/foreign-language (L2) learners’ processing of agreement morphology. It investigates the processing of grammatical and ungrammatical ...

Coughlin, Caitlyn E.; Tremblay, Annie

2013-03-07T23:59:59.000Z

53

Influence of limiting working memory resources on contextual facilitation in language processing   

E-Print Network [OSTI]

Language processing is a complex task requiring the integration of many different streams of information. Theorists have considered that working memory plays an important role in language processing and that a reduction ...

Stewart, Oliver William Thomas

2014-07-01T23:59:59.000Z

54

TROPOSPHERIC AEROSOL PROGRAM, PROGRAM PLAN, MARCH 2001  

SciTech Connect (OSTI)

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.

SCHWARTZ,S.E.; LUNN,P.

2001-03-01T23:59:59.000Z

55

Characterizing the formation of secondary organic aerosols  

SciTech Connect (OSTI)

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

Lunden, Melissa; Black, Douglas; Brown, Nancy

2004-02-01T23:59:59.000Z

56

ARM Aerosol Working Group Meeting  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)Productssondeadjustsondeadjust Documentation DataProductswsicloudwsicloudsummarygifAOS

57

Condensation in Totally Asymmetric Inclusion Process Joint work with Paul Chleboun and Stefan Grosskinsky  

E-Print Network [OSTI]

Condensation in Totally Asymmetric Inclusion Process Jiarui Cao Joint work with Paul Chleboun and Stefan Grosskinsky January 10, 2013 Jiarui Cao Condensation in Totally Asymmetric Inclusion Process #12;Outline 1. Totally Asymmetric Inclusion Process (TASIP) 2. Condensation in TASIP Model 3. Dynamics

Sengun, Mehmet Haluk

58

Process Innovation by working miners : a case of user innovation in copper mining industry  

E-Print Network [OSTI]

Employees are known to develop and use key process improvements. In this thesis, I explore innovation by mining employees working in Codelco, a Chilean mining company. The data on these innovations come from a contest ...

Burdiles Orellana, Sergio

2012-01-01T23:59:59.000Z

59

INSTITUT NATIONAL DE RECHERCHE EN INFORMATIQUE ET EN AUTOMATIQUE Scheduling and Controlling Work-In-Process  

E-Print Network [OSTI]

1 INSTITUT NATIONAL DE RECHERCHE EN INFORMATIQUE ET EN AUTOMATIQUE Scheduling and Controlling Work contrĂ´lables. inria-00072699,version1-24May2006 #12;3 Scheduling and controlling Work-In-Process: An On In this paper, we study an approach that aims at scheduling parts and controlling WIP. Hence, w are interested

Paris-Sud XI, Université de

60

Use of the ARM Measurement of Spectral Zenith Radiance For Better Understanding Of 3D Cloud-Radiation Processes and Aerosol-Cloud Interaction  

SciTech Connect (OSTI)

Our proposal focuses on cloud-radiation processes in a general 3D cloud situation, with particular emphasis on cloud optical depth and effective particle size. We also focus on zenith radiance measurements, both active and passive. The proposal has three main parts. Part One exploits the �¢����solar-background�¢��� mode of ARM lidars to allow them to retrieve cloud optical depth not just for thin clouds but for all clouds. This also enables the study of aerosol cloud interactions with a single instrument. Part Two exploits the large number of new wavelengths offered by ARM�¢����s zenith-pointing ShortWave Spectrometer (SWS), especially during CLASIC, to develop better retrievals not only of cloud optical depth but also of cloud particle size. We also propose to take advantage of the SWS�¢���� 1 Hz sampling to study the �¢����twilight zone�¢��� around clouds where strong aerosol-cloud interactions are taking place. Part Three involves continuing our cloud optical depth and cloud fraction retrieval research with ARM�¢����s 2NFOV instrument by, first, analyzing its data from the AMF-COPS/CLOWD deployment, and second, making our algorithms part of ARM�¢����s operational data processing.

D. Jui-Yuan Chiu

2010-10-19T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Application of computational fluid dynamics to aerosol sampling and concentration  

E-Print Network [OSTI]

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...

Hu, Shishan

2009-05-15T23:59:59.000Z

62

Use of the ARM Measurements of Spectral Zenith Radiance for Better Understanding of 3D Cloud-Radiation Processes & Aerosol-Cloud Interaction  

SciTech Connect (OSTI)

This project focuses on cloud-radiation processes in a general three-dimensional cloud situation, with particular emphasis on cloud optical depth and effective particle size. The proposal has two main parts. Part one exploits the large number of new wavelengths offered by the Atmospheric Radiation Measurement (ARM) zenith-pointing ShortWave Spectrometer (SWS), to develop better retrievals not only of cloud optical depth but also of cloud particle size. We also take advantage of the SWS’ high sampling resolution to study the “twilight zone” around clouds where strong aerosol-cloud interactions are taking place. Part two involves continuing our cloud optical depth and cloud fraction retrieval research with ARM’s 2-channel narrow vield-of-view radiometer and sunphotometer instrument by, first, analyzing its data from the ARM Mobile Facility deployments, and second, making our algorithms part of ARM’s operational data processing.

Chiu, Jui-Yuan Christine [University of Reading] [University of Reading

2014-04-10T23:59:59.000Z

63

Optimization of aerosol penetration through transport lines  

E-Print Network [OSTI]

will be minimum and -' he penetration of aerosols through the transport system will be maximal. It is the purpose of the study reported herein to experimentally investigate the optimization of aerosol penetration through transport systems and to obtain a... numbers less than 869, bounded the use of this model to Reynolds numbers less than or equal to 1100. 19 IV. SUNNARY OF WORK AND EXPERINENTAL NETHODOLOGY The purpose of the study reported herein was to further analyze the optimization of aerosol...

Wong Luque, Fermin Samuel

1992-01-01T23:59:59.000Z

64

Effects of operating conditions on a heat transfer fluid aerosol  

E-Print Network [OSTI]

of heat transfer fluid aerosols from process leaks. To simulate industrial leaks, aerosol formation from a plain orifice into ambient air is studied by measuring liquid drop sizes and size distributions at various distances from an orifice. Measurements...

Sukmarg, Passaporn

2000-01-01T23:59:59.000Z

65

Ganges Valley Aerosol Experiment: Science and Operations Plan  

SciTech Connect (OSTI)

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.

Kotamarthi, VR

2010-06-21T23:59:59.000Z

66

The nature of the working memory system underlying language processing and its relationship to the long-term memory system  

E-Print Network [OSTI]

This thesis examines two questions concerning the working memory system underlying language processing: (1) To what extent is the working memory system underlying language processing domain-specific? and (2) What is the ...

Fedorenko, Evelina Georgievna

2007-01-01T23:59:59.000Z

67

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

E-Print Network [OSTI]

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...

Glen, Crystal

2012-02-14T23:59:59.000Z

68

Evaluation of Transportation Vibration Associated with Relocation of Work in Process As Part of KCRIMS  

SciTech Connect (OSTI)

During relocation of the Kansas City Plant (KCP) from the site at Bannister Road to the site at Botts Road, work in process (WIP) within a production department must be transported. This report recommends packaging to mitigate vibration levels experienced by products during between-facility transportation. Measurements and analysis demonstrate that this mitigation results in vibration levels less than those experienced by the product during routine production processes within potentially damaging frequency ranges.

Hartwig, Troy

2013-04-01T23:59:59.000Z

69

Methodological utilities for organizing cooperative work process according to ISO 9001 standard recommendations  

E-Print Network [OSTI]

1 Methodological utilities for organizing cooperative work process according to ISO 9001 standard is based on the recommendations of ISO 9001 standard. Classical methods decompose a project into several, the recommendations of the ISO 9001 standard (ISO, 2000) are applied, which define different requirements to control

Paris-Sud XI, Université de

70

Governance work in inter-organizational networks: driving processes and Chahira Mehouachi,  

E-Print Network [OSTI]

, gain on transaction or productivity costs, improve inter-organizational learning, produce new knowledge1 Governance work in inter-organizational networks: driving processes and structures Chahira,version1-13Jul2013 Author manuscript, published in "29th EGOS Colloquium Sub-theme 14 Organizational

Paris-Sud XI, Université de

71

Aerosols, Clouds, and Climate Change Stephen E. Schwartz  

E-Print Network [OSTI]

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

Schwartz, Stephen E.

72

Executive function processes: inhibition, working memory, planning and attention in children and youth with Attention Deficit Hyperactivity Disorder  

E-Print Network [OSTI]

This study examines the roles of inhibition, attention, working memory, and planning in youth with and without ADHD. As conceptualized in theories of attention, inhibition, and working memory, difficulties with these executive processes interact...

Wolfe, Monica Eileen

2006-04-12T23:59:59.000Z

73

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...

74

Mass Spectral Evidence That Small Changes in Composition Caused by Oxidative Aging Processes Alter Aerosol CCN Properties  

E-Print Network [OSTI]

Mass Spectral Evidence That Small Changes in Composition Caused by Oxidative Aging Processes Alter that small changes in particle chemical composition caused by oxidation could increase the CCN activity increased cloud condensation nuclei (CCN) activity compared to their hydro- phobic counterparts. At present

75

The EM SSAB Annual Work Plan Process: Focusing Board Efforts and Resources - 13667  

SciTech Connect (OSTI)

One of the most daunting tasks for any new member of a local board of the Environmental Management Site Specific Advisory Board (EM SSAB) is to try to understand the scope of the clean-up activities going on at the site. In most cases, there are at least two or three major cleanup activities in progress as well as monitoring of past projects. When planning for future projects is added to the mix, the list of projects can be long. With the clean-up activities involving all major environmental media - air, water, soils, and groundwater, new EM SSAB members can find themselves totally overwhelmed and ineffective. Helping new members get over this initial hurdle is a major objective of EM and all local boards of the EM SSAB. Even as members start to understand the size and scope of the projects at a site, they can still be frustrated at the length of time it takes to see results and get projects completed. Many project and clean-up timelines for most of the sites go beyond 10 years, so it's not unusual for an EM SSAB member to see the completion of only 1 or 2 projects over the course of their 6-year term on the board. This paper explores the annual work planning process of the EM SSAB local boards, one tool that can be used to educate EM SSAB members into seeing the broader picture for the site. EM SSAB local work plans divide the site into projects focused on a specific environmental issue or media such as groundwater and/or waste disposal options. Projects are further broken down into smaller segments by highlighting major milestones. Using these metrics, local boards of the EM SSAB can start to quantify the effectiveness of the project in achieving the ultimate goal of site clean-up. These metrics can also trigger board advice and recommendations for EM. At the beginning of each fiscal year, the EM SSAB work plan provides a road map with quantifiable checkpoints for activities throughout the year. When the work plans are integrated with site-specific, enforceable regulatory milestones, they can provide a comprehensive work plan for not only the board, but also regulators, site contractors, and DOE. Because the work plans are reviewed and approved by DOE, they carry some weight in holding local boards of the EM SSAB accountable. This structure provides the basis for local boards to achieve their primary function, to provide DOE with information, advice, and recommendations concerning issues affecting the EM program at the site. (authors)

Young, Ralph [Paducah Citizens Advisory Board (United States)] [Paducah Citizens Advisory Board (United States)

2013-07-01T23:59:59.000Z

76

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

E-Print Network [OSTI]

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, ...

Kroll, Jesse

77

BESNARD, D. & CACITTI, L. (2001). Troubleshooting in mechanics: A heuristic matching process. Cognition, Technology & Work, 3, 150-160.  

E-Print Network [OSTI]

1 BESNARD, D. & CACITTI, L. (2001). Troubleshooting in mechanics: A heuristic matching process. Cognition, Technology & Work, 3, 150-160. TROUBLE-SHOOTING IN MECHANICS : A HEURISTIC MATCHING PROCESS with expert operators' reasoning processes in trouble-shooting. We want to know more about the information

Newcastle upon Tyne, University of

78

Improved solid aerosol generator  

DOE Patents [OSTI]

An improved solid aerosol generator used to produce a gas borne stream of dry, solid particles of predetermined size and concentration. The improved solid aerosol generator nebulizes a feed solution of known concentration with a flow of preheated gas and dries the resultant wet heated aerosol in a grounded, conical heating chamber, achieving high recovery and flow rates. 2 figs.

Prescott, D.S.; Schober, R.K.; Beller, J.

1988-07-19T23:59:59.000Z

79

The behavior of constant rate aerosol reactors  

SciTech Connect (OSTI)

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.

Friedlander, S.K.

1982-01-01T23:59:59.000Z

80

Development and application of new techniques for blast furnace process control at SSAB Tunnplaat, Luleaa Works  

SciTech Connect (OSTI)

SSAB Tunnplaat AB operates two blast furnaces (M1 and M2) in Luleaa. In recent years research efforts have to a great extent been aimed at the development of new techniques for blast furnace process control. An example is the installation of a burden profile measurement system, which was useful in the development of a new burden distribution praxis on the big furnace (M2), equipped with a bell-less-top. Hearth level detection and continuous measurement of the hot metal temperature in the runner are under evaluation. The purpose of these techniques is to give earlier information concerning the state of the blast furnace process. Parallel to this work, models for prediction of silicon in hot metal, the position and shape of the cohesive zone and slip-warning are being developed and tested off-line. These new models and information from new measuring techniques will be integrated into a new Operating Guidance System, hopefully resulting in a powerful tool in the efforts to stabilize blast furnace operations.

Braemming, M.; Hallin, M. [SSAB Tunnplaat AB, Luleaa (Sweden); Zuo, G. [Luleaa Univ. (Sweden). Dept. of Process Metallurgy

1995-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

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.

82

Attachment of radon progeny to cigarette-smoke aerosols  

SciTech Connect (OSTI)

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.

Biermann, A.H.; Sawyer, S.R.

1995-05-01T23:59:59.000Z

83

Reduce cycle time and work in process in a medical device factory : scheduling of needle hub molding machines  

E-Print Network [OSTI]

Many manufacturing firms have improved their operations by implementing a work-in-process (WIP) limiting control strategy. This project explores the application of this concept to limit WIP and reduce cycle time for the ...

Yao, Jing, M. Eng. Massachusetts Institute of Technology

2007-01-01T23:59:59.000Z

84

Reduced cycle time and work in process in a medical device factory : the problem and a proposed solution  

E-Print Network [OSTI]

Many manufacturing firms have improved their operations by implementing a work-in-process (WIP) limiting control strategy. This project explores the application of this concept to limit WIP and reduce cycle time for the ...

Qian, Yi, M. Eng. Massachusetts Institute of Technology

2007-01-01T23:59:59.000Z

85

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

SciTech Connect (OSTI)

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.

Marlow, W.H.

1988-12-31T23:59:59.000Z

86

Electrically Driven Technologies for Radioactive Aerosol Abatement  

SciTech Connect (OSTI)

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.

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

2003-01-28T23:59:59.000Z

87

Cloud Scavenging Effects on Aerosol Radiative and Cloud-nucleating Properties - Final Technical Report  

SciTech Connect (OSTI)

The optical properties of aerosol particles are the controlling factors in determining direct aerosol radiative forcing. These optical properties depend on the chemical composition and size distribution of the aerosol particles, which can change due to various processes during the particles’ lifetime in the atmosphere. Over the course of this project we have studied how cloud processing of atmospheric aerosol changes the aerosol optical properties. A counterflow virtual impactor was used to separate cloud drops from interstitial aerosol and parallel aerosol systems were used to measure the optical properties of the interstitial and cloud-scavenged aerosol. Specifically, aerosol light scattering, back-scattering and absorption were measured and used to derive radiatively significant parameters such as aerosol single scattering albedo and backscatter fraction for cloud-scavenged and interstitial aerosol. This data allows us to demonstrate that the radiative properties of cloud-processed aerosol can be quite different than pre-cloud aerosol. These differences can be used to improve the parameterization of aerosol forcing in climate models.

Ogren, John A.; Sheridan, Patrick S.; Andrews, Elisabeth

2009-03-05T23:59:59.000Z

88

Cloud-Driven Changes in Aerosol Optical Properties - Final Technical Report  

SciTech Connect (OSTI)

The optical properties of aerosol particles are the controlling factors in determining direct aerosol radiative forcing. These optical properties depend on the chemical composition and size distribution of the aerosol particles, which can change due to various processes during the particles’ lifetime in the atmosphere. Over the course of this project we have studied how cloud processing of atmospheric aerosol changes the aerosol optical properties. A counterflow virtual impactor was used to separate cloud drops from interstitial aerosol and parallel aerosol systems were used to measure the optical properties of the interstitial and cloud-scavenged aerosol. Specifically, aerosol light scattering, back-scattering and absorption were measured and used to derive radiatively significant parameters such as aerosol single scattering albedo and backscatter fraction for cloud-scavenged and interstitial aerosol. This data allows us to demonstrate that the radiative properties of cloud-processed aerosol can be quite different than pre-cloud aerosol. These differences can be used to improve the parameterization of aerosol forcing in climate models.

Ogren, John A.; Sheridan, Patrick S.; Andrews, Elisabeth

2007-09-30T23:59:59.000Z

89

Aerosol Science and Technology, 41:202216, 2007 Copyright c American Association for Aerosol Research  

E-Print Network [OSTI]

processes, such as con- densation, coagulation, gas-to-particle conversion (Reid et al. 1998), and particle Aerosol size distribution is, along with particle refractive in- dex and shape, one of important

90

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

E-Print Network [OSTI]

understanding of the key processes that govern the aerosol size distribution: · Gas-to-particle conversion--conversion, suspensions of solid or liquid particles, are an important multi- phase system. Aerosols scatter and absorb retrospectively and prospectively for different emissions scenarios. Important aerosol properties and processes

91

High Flash-point Fluid Flow System Aerosol Flammability Study and Combustion Mechanism Analysis  

E-Print Network [OSTI]

understanding of this combustion process. The potential application of the ignition delay will be beneficial to the mitigation timing and detector sensor setting of facilities to prevent aerosol cloud fires. Finally, the scientific method of aerosol...

Huang, Szu-Ying

2013-12-02T23:59:59.000Z

92

CHASER: An Innovative Satellite Mission Concept to Measure the Effects of Aerosols on Clouds and Climate  

E-Print Network [OSTI]

The formation of cloud droplets on aerosol particles, technically known as the activation of cloud condensation nuclei (CCN), is the fundamental process driving the interactions of aerosols with clouds and precipitation. ...

Rosenfeld, Daniel

93

Currently, there is a substantial research and development effort directed toward optical signal processing and electronic signal processing for fiber-optic communications. Much of the work  

E-Print Network [OSTI]

Abstract Currently, there is a substantial research and development effort directed toward optical signal processing and electronic signal processing for fiber-optic communications. Much of the work for telecommunication services. For optical signal proc- essing, a variety of approaches are available for implementing

Wu, Shin-Tson

94

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

SciTech Connect (OSTI)

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.

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

2011-07-06T23:59:59.000Z

95

EMSP Final Report: Electrically Driven Technologies for Radioactive Aerosol Abatement  

SciTech Connect (OSTI)

The purpose of this research project was to develop an improved understanding of how electrically 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. There was anecdotal evidence in the literature that acoustic agglomeration and electrical coalescence could be used together to change the size distribution of aerosol particles in such a way as to promote easier filtration and less frequent maintenance of filtration systems. As such, those electrically driven technologies could potentially be used as remote technologies for improved treatment; however, existing theoretical models are not suitable for prediction and design. To investigate the physics of such systems, and also to prototype a system for such processes, a collaborative project was undertaken between Oak Ridge National Laboratory (ORNL) and the University of Texas at Austin (UT). ORNL was responsible for the larger-scale prototyping portion of the project, while UT was primarily responsible for the detailed physics in smaller scale unit reactors. It was found that both electrical coalescence and acoustic agglomeration do in fact increase the rate of aggregation of aerosols. Electrical coalescence requires significantly less input power than acoustic agglomeration, but it is much less effective in its ability to aggregate/coalesce aerosols. The larger-scale prototype showed qualitatively similar results as the unit reactor tests, but presented more difficulty in interpretation of the results because of the complex multi-physics coupling that necessarily occur in all larger-scale system tests. An additional finding from this work is that low-amplitude oscillation may provide an alternative, non-invasive, non-contact means of controlling settling and/or suspension of solids. Further investigation would be necessary to evaluate its utility for radioactive waste treatment applications. This project did not uncover a new technology for radioactive waste treatment. While it may be possible that an efficient electrically driven technology for aerosol treatment could be developed, it appears that other technologies, such as steel and ceramic HEPA filters, can suitably solve this problem. If further studies are to be undertaken, additional fundamental experimentation and modeling is necessary to fully capture the physics; in addition, larger-scale tests are needed to demonstrate the treatment of flowing gas streams through the coupling of acoustic agglomeration with electrocoalescence.

DePaoli, D.W.

2003-01-22T23:59:59.000Z

96

Direct Aerosol Forcing Uncertainty  

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

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.

Mccomiskey, Allison

97

Journal de la Socit Franaise de Statistique Spatial extremes: Max-stable processes at work  

E-Print Network [OSTI]

and conditional simulation of max-stable processes. The paper ends with the modeling of extreme wind gustsSubmission Journal de la Société Française de Statistique Spatial extremes: Max-stable processes many developments to the functional extreme value theory have been made during the last decades

Ribatet, Mathieu

98

Development and Characterization of a Thermodenuder for Aerosol Volatility Measurements  

SciTech Connect (OSTI)

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.

Dr. Timothy Onasch

2009-09-09T23:59:59.000Z

99

Vacuum-free lamination of low work function cathode for efficient solution-processed organic light-emitting diodes  

E-Print Network [OSTI]

-coated organic light-emitting diode is transferred from a soft polydimethylsiloxane (PDMS) mold by lamination, or blade coating [1,2] for organic light emitting diode (OLED) as well as solar cell. The top electrodeVacuum-free lamination of low work function cathode for efficient solution-processed organic light-emitting

Meng, Hsin-Fei

100

Year Report (FY 2000) Evaluation of uncertainties in satellite retrievals of aerosol  

E-Print Network [OSTI]

. Third Year Statement of Work 1. Construct clean aerosol data sets for the Mauna Loa (Hawaii), and Cheeka retrievals to the observed variability of ae

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Effects of aerosols on deep convective cumulus clouds  

E-Print Network [OSTI]

This work investigates the effects of anthropogenic aerosols on deep convective clouds and the associated radiative forcing in the Houston area. The Goddard Cumulus Ensemble model (GCE) coupled with a spectral-bin microphysics is employed...

Fan, Jiwen

2009-05-15T23:59:59.000Z

102

Computational Fluid Dynamics Study of Aerosol Transport and Deposition Mechanisms  

E-Print Network [OSTI]

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...

Tang, Yingjie

2012-07-16T23:59:59.000Z

103

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)]

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

Sivaraman, Chitra; Flynn, Connor

104

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)]

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

Newsom, Rob; Goldsmith, John

105

Demonstration of base catalyzed decomposition process, Navy Public Works Center, Guam, Mariana Islands  

SciTech Connect (OSTI)

Base Catalyzed Decomposition (BCD) is a chemical dehalogenation process designed for treating soils and other substrate contaminated with polychlorinated biphenyls (PCB), pesticides, dioxins, furans, and other hazardous organic substances. PCBs are heavy organic liquids once widely used in industry as lubricants, heat transfer oils, and transformer dielectric fluids. In 1976, production was banned when PCBs were recognized as carcinogenic substances. It was estimated that significant quantities (one billion tons) of U.S. soils, including areas on U.S. military bases outside the country, were contaminated by PCB leaks and spills, and cleanup activities began. The BCD technology was developed in response to these activities. This report details the evolution of the process, from inception to deployment in Guam, and describes the process and system components provided to the Navy to meet the remediation requirements. The report is divided into several sections to cover the range of development and demonstration activities. Section 2.0 gives an overview of the project history. Section 3.0 describes the process chemistry and remediation steps involved. Section 4.0 provides a detailed description of each component and specific development activities. Section 5.0 details the testing and deployment operations and provides the results of the individual demonstration campaigns. Section 6.0 gives an economic assessment of the process. Section 7.0 presents the conclusions and recommendations form this project. The appendices contain equipment and instrument lists, equipment drawings, and detailed run and analytical data.

Schmidt, A.J.; Freeman, H.D.; Brown, M.D.; Zacher, A.H.; Neuenschwander, G.N.; Wilcox, W.A.; Gano, S.R. [Pacific Northwest National Lab., Richland, WA (United States)] [Pacific Northwest National Lab., Richland, WA (United States); Kim, B.C.; Gavaskar, A.R. [Battelle Columbus Div., OH (United States)] [Battelle Columbus Div., OH (United States)

1996-02-01T23:59:59.000Z

106

AEROSOL PARTICLE COLLECTOR DESIGN STUDY  

SciTech Connect (OSTI)

A computational evaluation of a particle collector design was performed to evaluate the behavior of aerosol particles in a fast flowing gas stream. The objective of the work was to improve the collection efficiency of the device while maintaining a minimum specified air throughput, nominal collector size, and minimal power requirements. The impact of a range of parameters was considered subject to constraints on gas flow rate, overall collector dimensions, and power limitations. Potential improvements were identified, some of which have already been implemented. Other more complex changes were identified and are described here for further consideration. In addition, fruitful areas for further study are proposed.

Lee, S; Richard Dimenna, R

2007-09-27T23:59:59.000Z

107

Modal aerosol dynamics modeling  

SciTech Connect (OSTI)

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.

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

1991-02-01T23:59:59.000Z

108

Emerging Issues in Nanoparticle Aerosol Science and Technology Workshop report sponsored by: NSF, Southern California Particle Center and UCLA  

E-Print Network [OSTI]

has responsibility for nuclear reactor safety which includes emissions of radioactive particles pollution sources, (2) industrial production of nanoparticle reinforcing fillers such as carbon black nanoparticle products by aerosol processes, (4) atmospheric dynamics of fractal-like nanoparticle aerosols (e

Jimenez, Jose-Luis

109

Intercomparison and evaluation of global aerosol microphysical properties among AeroCom models of a range of complexity  

E-Print Network [OSTI]

Many of the next generation of global climate models will include aerosol schemes which explicitly simulate the microphysical processes that determine the particle size distribution. These models enable aerosol optical ...

Ridley, David Andrew

110

Preparation of ferric-sulfide-based catalysts using an aerosol technique  

SciTech Connect (OSTI)

Iron sulfides are used as catalysts for direct coal liquefaction. They are reasonably active, cheap, and environmentally benign. This permits their use as once-through, non-regenerated catalysts. Our work in this area is based on the products of disproportionation of ferric sulfide, produced in sufficiently small particle sizes. The small particle sizes have been produced by in-situ impregnation or by using an aerosol reactor. This talk will concentrate on the aerosol process. The resulting particles have been characterized and used as catalysts for coal liquefaction. The effects of precursor solution concentration and the pressure and temperature in the aerosol reactor on the performance of the catalysts have been noted. We have recently investigated the effect of adding small amounts of a second metal to the catalyst. Multi-metal catalysts prepared to date with the aerosol technique include Fe-Cu-S and Fe-Zn-S, each with 10% additive, and Fe-Cu-Zn-S, with 10% Cu and 5% Zn.

Stiller, A.H.; Dadyburjor, D.B.; Stinespring, C.D. [West Virginia Univ., Morgantown, WV (United States)] [and others

1995-12-01T23:59:59.000Z

111

Aerosol Sampler Operations Manual  

E-Print Network [OSTI]

-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

Fischer, Emily V.

112

Aerosol Optical Depth Value-Added Product Report  

SciTech Connect (OSTI)

This document describes the process applied to retrieve aerosol optical depth (AOD) from multifilter rotating shadowband radiometers (MFRSR) and normal incidence multifilter radiometers (NIMFR) operated at the ARM Climate Research Facility’s ground-based facilities.

Koontz, A; Hodges, G; Barnard, J; Flynn, C; Michalsky, J

2013-03-17T23:59:59.000Z

113

Phase transformation and growth of hygroscopic aerosols  

SciTech Connect (OSTI)

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.

Tang, I.N.

1999-11-01T23:59:59.000Z

114

CADS:Cantera Aerosol Dynamics Simulator.  

SciTech Connect (OSTI)

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.

Moffat, Harry K.

2007-07-01T23:59:59.000Z

115

E-Print Network 3.0 - aerosol chemical composition Sample Search...  

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

and temporal emissions of ozone... and aerosol through chemical formation and loss, transport, and deposition processes? 2. Measure distributions... and climate variability and...

116

Sensitivity of Remote Aerosol Distributions to Representation of Cloud-Aerosol Interactions in a Global Climate Model  

SciTech Connect (OSTI)

Many global aerosol and climate models, including the widely used Community Atmosphere Model version 5 (CAM5), have large biases in predicting aerosols in remote regions such as upper troposphere and high latitudes. In this study, we conduct CAM5 sensitivity simulations to understand the role of key processes associated with aerosol transformation and wet removal affecting the vertical and horizontal long-range transport of aerosols to the remote regions. Improvements are made to processes that are currently not well represented in CAM5, which are guided by surface and aircraft measurements together with results from a multi-scale aerosol-climate model (PNNL-MMF) that explicitly represents convection and aerosol-cloud interactions at cloud-resolving scales. We pay particular attention to black carbon (BC) due to its importance in the Earth system and the availability of measurements. We introduce into CAM5 a new unified scheme for convective transport and aerosol wet removal with explicit aerosol activation above convective cloud base. This new implementation reduces the excessive BC aloft to better simulate observed BC profiles that show decreasing mixing ratios in the mid- to upper-troposphere. After implementing this new unified convective scheme, we examine wet removal of submicron aerosols that occurs primarily through cloud processes. The wet removal depends strongly on the sub-grid scale liquid cloud fraction and the rate of conversion of liquid water to precipitation. These processes lead to very strong wet removal of BC and other aerosols over mid- to high latitudes during winter months. With our improvements, the Arctic BC burden has a10-fold (5-fold) increase in the winter (summer) months, resulting in a much better simulation of the BC seasonal cycle as well. Arctic sulphate and other aerosol species also increase but to a lesser extent. An explicit treatment of BC aging with slower aging assumptions produces an additional 30-fold (5-fold) increase in the Arctic winter (summer) BC burden. This BC aging treatment, however, has minimal effect on other under-predicted species. Interestingly, our modifications to CAM5 that aim at improving prediction of high-latitude and upper tropospheric aerosols also produce much better AOD and AAOD over various other regions globally when compared to multi-year AERONET retrievals. The improved aerosol distributions have impacts on other aspects of CAM5, improving the simulation of global mean liquid water path and cloud forcing.

Wang, Hailong; Easter, Richard C.; Rasch, Philip J.; Wang, Minghuai; Liu, Xiaohong; Ghan, Steven J.; Qian, Yun; Yoon, Jin-Ho; Ma, Po-Lun; Vinoj, V.

2013-06-05T23:59:59.000Z

117

Highly stable aerosol generator  

DOE Patents [OSTI]

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.

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

1981-11-03T23:59:59.000Z

118

Intercomparison and Evaluation of Global Aerosol Microphysical Properties among AeroCom Models of a Range of Complexity  

SciTech Connect (OSTI)

Many of the next generation of global climate models will include aerosol schemes which explicitly simulate the microphysical processes that determine the particle size distribution. These models enable aerosol optical properties and cloud condensation nuclei (CCN) concentrations to be determined by fundamental aerosol processes, which should lead to a more physically based simulation of aerosol direct and indirect radiative forcings. This study examines the global variation in particle size distribution simulated by twelve global aerosol microphysics models to quantify model diversity and to identify any common biases against observations. Evaluation against size distribution measurements from a new European network of aerosol supersites shows that the mean model agrees quite well with the observations at many sites on the annual mean, but there are some seasonal biases common to many sites. In particular, at many of these European sites, the accumulation mode number concentration is biased low during winter and Aitken mode concentrations tend to be overestimated in winter and underestimated in summer. At high northern latitudes, the models strongly underpredict Aitken and accumulation particle concentrations compared to the measurements, consistent with previous studies that have highlighted the poor performance of global aerosol models in the Arctic. In the marine boundary layer, the models capture the observed meridional variation in the size distribution, which is dominated by the Aitken mode at high latitudes, with an increasing concentration of accumulation particles with decreasing latitude. Considering vertical profiles, the models reproduce the observed peak in total particle concentrations in the upper troposphere due to new particle formation, although modelled peak concentrations tend to be biased high over Europe. Overall, the results suggest that most global aerosol microphysics models simulate the global variation of the particle size distribution with a good degree of skill, but some models are in poor agreement with the observations. Further work is required to better constrain size-resolved primary and secondary particle number sources, and an improved understanding of nucleation and growth (e.g. the role of nitrate and secondary organics) will improve the fidelity of simulated particle size distributions.

Mann, G. W.; Carslaw, K. S.; Reddington, C. L.; Pringle, K. J.; Schulz, M.; Asmi, A.; Spracklen, D. V.; Ridley, D. A.; Woodhouse, M. T.; Lee, L. A.; Zhang, Kai; Ghan, Steven J.; Easter, Richard C.; Liu, Xiaohong; Stier, P.; Lee, Y. H.; Adams, P. J.; Tost, H.; Lelieveld, J.; Bauer, S.; Tsigaridis, Kostas; van Noije, T.; Strunk, A.; Vignati, E.; Bellouin, N.; Dalvi, M.; Johnson, C. E.; Bergman, T.; Kokkola, H.; Von Salzen, Knut; Yu, Fangqun; Luo, Gan; Petzold, A.; Heintzenberg, J.; Clarke, A. D.; Ogren, J. A.; Gras, J.; Baltensperger, Urs; Kaminski, U.; Jennings, S. G.; O'Dowd, C. D.; Harrison, R. M.; Beddows, D. C.; Kulmala, M.; Viisanen, Y.; Ulevicius, V.; Mihalopoulos, Nikos; Zdimal, V.; Fiebig, M.; Hansson, H. C.; Swietlicki, E.; Henzing, J. S.

2014-05-13T23:59:59.000Z

119

Radiative Processes Working Group  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared at 278, 298, and 323Program Accomplishments of themeeting, 10-14

120

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

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Statistical analysis of 4-year observations of aerosol sizes in a semi-rural continental environment  

E-Print Network [OSTI]

Statistical analysis of 4-year observations of aerosol sizes in a semi-rural continental. Introduction Formation of new aerosol particles via gas-to-particle conver- sion is an important process, which to understanding how new particle formation (NPF) processes lead to formation of cloud condensation nuclei (CCN

Lee, Shan-Hu

122

Analysis of the working process and mechanical losses in a Stirling engine for a solar power unit  

SciTech Connect (OSTI)

In this paper a second level mathematical model for the computational simulation of the working process of a 1-kW Stirling engine has been used and the results obtained are presented. The internal circuit of the engine in the calculation scheme was divided into five chambers, namely, the expansion space, heater, regenerator, cooler and the compression space, and the governing system of ordinary differential equations for the energy and mass conservation were solved in each chamber by Euler`s method. In addition, mechanical losses in the construction of the engine have been determined and the computational results show that the mechanical losses for this particular design of the Stirling engine may be up to 50% of the indicated power of the engine.

Makhkamov, K.K. [Uzbek Academy of Sciences, Tashkent (Uzbekistan). Physical and Technical Inst.; Ingham, D.B. [Univ. of Leeds (United Kingdom). Dept. of Applied Mathematics

1999-05-01T23:59:59.000Z

123

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

SciTech Connect (OSTI)

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.

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

124

MICS Asia Phase II - Sensitivity to the aerosol module  

E-Print Network [OSTI]

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...

Sartelet, Karine; Sportisse, Bruno

2007-01-01T23:59:59.000Z

125

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)]

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

Sivaraman, Chitra; Flynn, Connor

126

Experimental study of nuclear workplace aerosol samplers  

E-Print Network [OSTI]

LITERATURE REVIEW Aerosol Losses in an Inlet . Aerosol Losses in a Transport System Aerosol Losses in CAMs Critical Flow Venturi 8 13 15 16 EXPERIMENT PROCEDURE 18 CAM Evaluation Consideration FAS Evaluation Consideration Test Protocol Mixing... Chamber Setup High Speed Aerosol Wind Tunnel Setup Low Speed Aerosol Wind Tunnel Setup Critical Flow Venturi 18 19 21 22 24 25 27 RESULTS AND DISCUSSION Page 28 Aerosol Penetration through Transport Systems and CAM Areal Uniformity Deposits...

Parulian, Antony

2012-06-07T23:59:59.000Z

127

Production Mechanism, Number Concentration, Size Distribution, Chemical Composition, and Optical Properties of Sea Spray Aerosols Workshop, Summer 2012  

SciTech Connect (OSTI)

The objective of this workshop was to address the most urgent open science questions for improved quantification of sea spray aerosol-radiation-climate interactions. Sea spray emission and its influence on global climate remains one of the most uncertain components of the aerosol-radiation-climate problem, but has received less attention than other aerosol processes (e.g. production of terrestrial secondary organic aerosols). Thus, the special emphasis was placed on the production flux of sea spray aerosol particles, their number concentration and chemical composition and properties.

Meskhidze, Nicholas [NCSU] [NCSU

2013-10-21T23:59:59.000Z

128

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...

129

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)...

130

Effects of Sea-Salt Aerosols on Precipitation in Simulations of Shallow Cumulus  

E-Print Network [OSTI]

A suite of large-eddy simulations with size-resolving microphysical processes was performed in order to assess effects of sea-salt aerosols on precipitation process in trade cumulus. Simulations based on observations from ...

Kogan, Yefim L.; Mechem, David B.; Choi, Kityan

2012-02-01T23:59:59.000Z

131

Laboratory Experiments and Instrument Development for the Study of Atmospheric Aerosols  

SciTech Connect (OSTI)

Soot particles are generated by incomplete combustion of fossil and biomass fuels. Through direct effects clear air aerosols containing black carbon (BC) such as soot aerosols, absorb incoming light heating the atmosphere, while most other aerosols scatter light and produce cooling. Even though BC represents only 1-2% of the total annual emissions of particulate mass to the atmosphere, it has been estimated that the direct radiative effect of BC is the second-most important contributor to global warming after absorption by CO2. Ongoing studies continue to underscore the climate forcing importance of black carbon. However, estimates of the radiative effects of black carbon on climate remain highly uncertain due to the complexity of particles containing black carbon. Quantitative measurement of BC is challenging because BC often occurs in highly non-spherical soot particles of complex morphology. Freshly emitted soot particles are typically fractal hydrophobic aggregates. The aggregates consist of black carbon spherules with diameters typically in the range of about 15-40 nm, and they are usually coated by adsorbed polyaromatic hydrocarbons (PAHs) produced during combustion. Diesel-generated soot particles are often emitted with an organic coating composed primarily of lubricating oil and unburned fuel, as well as well as PAH compounds. Sulfuric acid has also been detected in diesel and aircraft-emitted soot particles. In the course of aging, these particle coatings may be substantially altered by chemical reactions and/or the deposition of other materials. Such processes transform the optical and CCN properties of the soot aerosols in ways that are not yet well understood. Our work over the past seven years consisted of laboratory research, instrument development and characterization, and field studies with the central focus of improving our understanding of the black carbon aerosol climate impacts. During the sixth year as well as during this seventh year (no-cost extension period) of our grant, we extended our studies to perform experiments on the controlled production and characterization of secondary organic aerosol.

Davidovits, Paul

2011-12-10T23:59:59.000Z

132

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)

[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.

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

2003-02-15T23:59:59.000Z

133

Parameterizations of Cloud Microphysics and Indirect Aerosol Effects  

SciTech Connect (OSTI)

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

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

2014-05-19T23:59:59.000Z

134

The Nearby Supernova Factory Ozone + Aerosol + Rayleigh  

E-Print Network [OSTI]

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

135

E-Print Network 3.0 - aerosols dans le Sample Search Results  

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

AN ADVECTIVE HYPOTHESIS FOR THE FORMATION OF THE STRATOSPHERIC AEROSOL LAYER M. KRITZ Abstract... . -- In earlier work we concluded that the large ( 0.3 u rad) particles of...

136

Safe Nanotechnology in the Work Space Different types of nanoparticles are made or used in various industrial processes. To  

E-Print Network [OSTI]

Safety Safe Nanotechnology in the Work Space Different types of nanoparticles are made or used://www.cdc.gov/niosh/docs/2008-112/pdfs/2008-112.pdf http://www.nanoshel.com/buy-nanotubes.php #12;Safety Safe Nanotechnology-112/pdfs/2008-112.pdf #12;Safety Safe Nanotechnology in the Work Space Exposure: Inhalation--The most

Cohen, Robert E.

137

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

SciTech Connect (OSTI)

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.

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

138

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...

139

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...

140

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...

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

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

142

Aerosol Processes Enabling Solar Energy Applications.  

E-Print Network [OSTI]

??Development of alternative energy sources is essential to satisfy future energy demands. While remaining fossil fuel resources may substantially meet these demands, anthropogenic carbon dioxide:… (more)

An, Woo Jin

2012-01-01T23:59:59.000Z

143

ARM - Cumulus Humilis Aerosol Processing Study (CHAPS)  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformationbudapest Comments? We would love toContact Information Related Links TWP-ICESitesStudy (CHAPS)

144

8, 68456901, 2008 Aerosol optical  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

145

DOE research on atmospheric aerosols  

SciTech Connect (OSTI)

Atmospheric aerosols are the subject of a significant component of research within DOE`s environmental research activities, mainly under two programs within the Department`s Environmental Sciences Division, the Atmospheric Radiation Measurement (ARM) Program and the Atmospheric Chemistry Program (ACP). Research activities conducted under these programs include laboratory experiments, field measurements, and theoretical and modeling studies. The objectives and scope of these programs are briefly summarized. The ARM Program is the Department`s major research activity focusing on atmospheric processes pertinent to understanding global climate and developing the capability of predicting global climate change in response to energy related activities. The ARM approach consists mainly of testing and improving models using long-term measurements of atmospheric radiation and controlling variables at highly instrumented sites in north central Oklahoma, in the Tropical Western Pacific, and on the North Slope of Alaska. Atmospheric chemistry research within DOE addresses primarily the issue of atmospheric response to emissions from energy-generation sources. As such this program deals with the broad topic known commonly as the atmospheric source-receptor sequence. This sequence consists of all aspects of energy-related pollutants from the time they are emitted from their sources to the time they are redeposited at the Earth`s surface.

Schwartz, S.E.

1995-11-01T23:59:59.000Z

146

Aerosols and clouds in chemical transport models and climate models.  

SciTech Connect (OSTI)

Clouds exert major influences on both shortwave and longwave radiation as well as on the hydrological cycle. Accurate representation of clouds in climate models is a major unsolved problem because of high sensitivity of radiation and hydrology to cloud properties and processes, incomplete understanding of these processes, and the wide range of length scales over which these processes occur. Small changes in the amount, altitude, physical thickness, and/or microphysical properties of clouds due to human influences can exert changes in Earth's radiation budget that are comparable to the radiative forcing by anthropogenic greenhouse gases, thus either partly offsetting or enhancing the warming due to these gases. Because clouds form on aerosol particles, changes in the amount and/or composition of aerosols affect clouds in a variety of ways. The forcing of the radiation balance due to aerosol-cloud interactions (indirect aerosol effect) has large uncertainties because a variety of important processes are not well understood precluding their accurate representation in models.

Lohmann,U.; Schwartz, S. E.

2008-03-02T23:59:59.000Z

147

Thermophoretic separation of aerosol particles from a sampled gas stream  

DOE Patents [OSTI]

This disclosure relates to separation of aerosol particles from gas samples withdrawn from within a contained atmosphere, such as containment vessels for nuclear reactors or other process equipment where remote gaseous sampling is required. It is specifically directed to separation of dense aerosols including particles of any size and at high mass loadings and high corrosivity. The United States Government has rights in this invention pursuant to Contract DE-AC06-76FF02170 between the US Department of Energy and Westinghouse Electric Corporation.

Postma, A.K.

1984-09-07T23:59:59.000Z

148

Lognormal Size Distribution Theory for Deposition of Polydisperse Aerosol Particles  

SciTech Connect (OSTI)

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.

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

2000-07-15T23:59:59.000Z

149

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

SciTech Connect (OSTI)

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.

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

2001-04-01T23:59:59.000Z

150

Suspended plutonium aerosols near a soil cleanup site on Johnston Atoll in 1992  

SciTech Connect (OSTI)

Plutonium aerosol monitoring was conducted for one month near the 1992 operation of a stationary sorting system used to {open_quotes}mine{close_quotes} contaminated soil on Johnston Atoll. Pairs of high volume cascade impactors and a high volume air sampler were located at each of three locations of the process stream: the {open_quotes}spoils pile{close_quote} that was the feedstock, the {open_quotes}plant area{close_quotes} near the-hot soil gate of the sorter, and the {open_quotes}clean pile{close_quotes} conveyer area where sorted clean soil was moved. These locations were monitored only during the working hours, while air monitoring was also done at an upwind, uncontaminated {open_quotes}background{close_quotes} area 24-hours per day. The three monitoring locations were extremely dusty, even though there were frequent rains during the period of operation. Total suspended particulate mass loadings were 178 {mu}g/m{sup 3} at the spoils pile, 93 {mu}g/m{sup 3} at the plant area, and 79 {mu}g/m{sup 3} at the clean pile during this period, when background mass loadings were 41 {mu}g/m{sup 3}. There was no practical difference in the aerosol specific activity between the three locations, however, which had a median value of 3.64 pCi/g (135 Bq/kg). The aerosol specific activity is enhanced by a factor of 3 over the specific activity of the processed contaminant soil. This is about the same enhancement factor as found by other studies of road traffic, bulldozing, and agricultural operations. Specific activity of processed soil was 1.35 pCi/g (50 Bq/kg). The median mass-loading of the three downwind sites was 109 {mu}g/m{sup 3} (uncorrected for the sea spray contribution), so that the median concentrations in air using the median aerosol specific activity was calculated to be 397 aCi/m{sup 3} (15 {mu}Bq/m{sup 3}). Measured Pu concentrations ranged from 280 to 1508 aCi/m{sup 3} (10 to 56 {mu}Bq/m3).

Shinn, J.H.; Fry, C.F.; Johnson, J.S.

1994-02-01T23:59:59.000Z

151

Nuclear Aerosols: Direct Simulation and Elucidation of the Role of Multiple Components, Radioactivity, Charge, Shape and Spatial Inhomogeneity  

SciTech Connect (OSTI)

Nuclear aerosols can originate from severe core damae in light water reactors, core disruptive accidents in fast reactors, nuclear accidents during nuclear material transport, at waste disposal sites, or explosions. These aerosols evolve under natural transport processes as well as under the influence of engineered safety features. Such aerosols can be hazardous for the equipment inside the reactor, and when leaked into the environment, pose potential risks to the public. Hence, the origin, movement and distribution of these aerosols need to be studied and controlled.

Sudarshan K. Loyalka

2008-10-12T23:59:59.000Z

152

Direct and semi-direct aerosol effects of Southern African1 biomass burning aerosol2  

E-Print Network [OSTI]

1 Direct and semi-direct aerosol effects of Southern African1 biomass burning aerosol2 Naoko effects of biomass burning aerosols from Southern African fires9 during July-October are investigated region the overall TOA radiative effect from the23 biomass burning aerosols is almost zero due

Wood, Robert

153

Composition and Reactions of Atmospheric Aerosol Particles  

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

Source type and mechanism information for the four aerosol samples gathered from the Caribbean, the Sea of Japan, and New Jersey. One way to gauge an aerosol's ability to stay...

154

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

SciTech Connect (OSTI)

Any attempt to reconcile observed surface temperature changes within the last 150 years to changes simulated by climate models that include various atmospheric forcings is sensitive to the changes attributed to aerosols and aerosol-cloud-climate interactions, which are the main contributors that may well balance the positive forcings associated with greenhouse gases, absorbing aerosols, ozone related changes, etc. These aerosol effects on climate, from various modeling studies discussed in Menon (2004), range from +0.8 to -2.4 W m{sup -2}, with an implied value of -1.0 W m{sup -2} (range from -0.5 to -4.5 W m{sup -2}) for the aerosol indirect effects. Quantifying the contribution of aerosols and aerosol-cloud interactions remain complicated for several reasons some of which are related to aerosol distributions and some to the processes used to represent their effects on clouds. Aerosol effects on low lying marine stratocumulus clouds that cover much of the Earth's surface (about 70%) have been the focus of most of prior aerosol-cloud interaction effect simulations. Since cumulus clouds (shallow and deep convective) are short lived and cover about 15 to 20% of the Earth's surface, they are not usually considered as radiatively important. However, the large amount of latent heat released from convective towers, and corresponding changes in precipitation, especially in biomass regions due to convective heating effects (Graf et al. 2004), suggest that these cloud systems and aerosol effects on them, must be examined more closely. The radiative heating effects for mature deep convective systems can account for 10-30% of maximum latent heating effects and thus cannot be ignored (Jensen and Del Genio 2003). The first study that isolated the sensitivity of cumulus clouds to aerosols was from Nober et al. (2003) who found a reduction in precipitation in biomass burning regions and shifts in circulation patterns. Aerosol effects on convection have been included in other models as well (cf. Jacobson, 2002) but the relative impacts on convective and stratiform processes were not separated. Other changes to atmospheric stability and thermodynamical quantities due to aerosol absorption are also known to be important in modifying cloud macro/micro properties. Linkages between convection and boreal biomass burning can also impact the upper troposphere and lower stratosphere, radiation and cloud microphysical properties via transport of tropospheric aerosols to the lower stratosphere during extreme convection (Fromm and Servranckx 2003). Relevant questions regarding the impact of biomass aerosols on convective cloud properties include the effects of vertical transport of aerosols, spatial and temporal distribution of rainfall, vertical shift in latent heat release, phase shift of precipitation, circulation and their impacts on radiation. Over land surfaces, a decrease in surface shortwave radiation ({approx} 3-6 W m{sup -2} per decade) has been observed between 1960 to 1990, whereas, increases of 0.4 K in land temperature during the same period that occurred have resulted in speculations that evaporation and precipitation should also have decreased (Wild et al. 2004). However, precipitation records for the same period over land do not indicate any significant trend (Beck et al. 2005). The changes in precipitation are thought to be related to increased moisture advection from the oceans (Wild et al. 2004), which may well have some contributions from aerosol-radiation-convection coupling that could modify circulation patterns and hence moisture advection in specific regions. Other important aspects of aerosol effects, besides the direct, semi-direct, microphysical and thermodynamical impacts include alteration of surface albedos, especially snow and ice covered surfaces, due to absorbing aerosols. These effects are uncertain (Jacobson, 2004) but may produce as much as 0.3 W m{sup -2} forcing in the Northern hemisphere that could contribute to melting of ice and permafrost and change in the length of the season (e.g. early arrival of Spring

Menon, Surabi; Del Genio, Anthony D.

2007-09-03T23:59:59.000Z

155

Collection of Aerosol Particles by a Conducting Sphere in an External Electric Field-Continuum Regime Approximation  

E-Print Network [OSTI]

caseswhere some effects are absent. INTRODUCTION The collision and coagulation process of aerosol particles to a consid- erable extent the size distribution and thus the reaction rate of the reactants. In this paper weCollection of Aerosol Particles by a Conducting Sphere in an External Electric Field

Wang, Pao K.

156

6, 93519388, 2006 Aerosol-cloud  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

157

Laboratory Testing of Aerosol for Enclosure Air Sealing  

SciTech Connect (OSTI)

Space conditioning energy use can be significantly reduced by addressing uncontrolled infiltration and exfiltration through the envelope of a building. A process for improving the air tightness of a building envelope by sealing shell leaks with an aerosol sealing technology is presented. Both retrofit and new construction applications are possible through applying this process either in attics and crawlspaces or during rough-in stage.

Harrington, C.; Modera, M.

2012-05-01T23:59:59.000Z

158

Quantifying the Uncertainties of Aerosol Indirect Effects and Impacts on Decadal-Scale Climate Variability in NCAR CAM5 and CESM1  

SciTech Connect (OSTI)

The main goal of this project is to systematically quantify the major uncertainties of aerosol indirect effects due to the treatment of moist turbulent processes that drive aerosol activation, cloud macrophysics and microphysics in response to anthropogenic aerosol perturbations using the CAM5/CESM1. To achieve this goal, the P.I. hired a postdoctoral research scientist (Dr. Anna Fitch) who started her work from the Nov.1st.2012. In order to achieve the project goal, the first task that the Postdoc. and the P.I. did was to quantify the role of subgrid vertical velocity variance on the activation and nucleation of cloud liquid droplets and ice crystals and its impact on the aerosol indirect effect in CAM5. First, we analyzed various LES cases (from dry stable to cloud-topped PBL) to check whether this isotropic turbulence assumption used in CAM5 is really valid. It turned out that this isotropic turbulence assumption is not universally valid. Consequently, from the analysis of LES, we derived an empirical formulation relaxing the isotropic turbulence assumption used for the CAM5 aerosol activation and ice nucleation, and implemented the empirical formulation into CAM5/CESM1, and tested in the single-column and global simulation modes, and examined how it changed aerosol indirect effects in the CAM5/CESM1. These results were reported in the poster section in the 18th Annual CESM workshop held in Breckenridge, CO during Jun.17-20.2013. While we derived an empirical formulation from the analysis of couple of LES from the first task, the general applicability of that empirical formulation was questionable, because it was obtained from the limited number of LES simulations. The second task we did was to derive a more fundamental analytical formulation relating vertical velocity variance to TKE using other information starting from basic physical principles. This was a somewhat challenging subject, but if this could be done in a successful way, it could be directly implemented into the CAM5 as a practical parameterization, and substantially contributes to achieving the project goal. Through an intensive research for about one year, we found appropriate mathematical formulation and tried to implement it into the CAM5 PBL and activation routine as a practical parameterized numerical code. During these processes, however, the Postdoc applied for another position in Sweden, Europe, and accepted a job offer there, and left NCAR in August 2014. In Sweden, Dr. Anna Fitch is still working on this subject in a part time, planning to finalize the research and to write the paper in a near future.

Park, Sungsu

2014-12-12T23:59:59.000Z

159

Analysis of fluidized beds for the simultaneous aerosol separation and heat recovery  

SciTech Connect (OSTI)

A mathematical model is developed to describe the performance of fluidized beds for the simultaneous heat recovery and aerosol separation. This new concept is analyzed in light of the various transport processes taking place within the bed. A two-phase model is developed for the system in which heat and aerosol particles are transferred from the bubble phase to the emulsion phase. In addition to aerosol separation via diffusion, interception, impaction and electrostatic precipitation, thermophoretic collection is also analyzed. The results indicate that high thermal and separation efficiencies can be obtained.

El-Halwagi, M.M. [Auburn Univ., AL (United States)

1993-01-01T23:59:59.000Z

160

Constraining cloud lifetime effects of aerosols using A-Train satellite observations  

SciTech Connect (OSTI)

Aerosol indirect effects have remained the largest uncertainty in estimates of the radiative forcing of past and future climate change. Observational constraints on cloud lifetime effects are particularly challenging since it is difficult to separate aerosol effects from meteorological influences. Here we use three global climate models, including a multi-scale aerosol-climate model PNNL-MMF, to show that the dependence of the probability of precipitation on aerosol loading, termed the precipitation frequency susceptibility (S{sub pop}), is a good measure of the liquid water path response to aerosol perturbation ({lambda}), as both Spop and {lambda} strongly depend on the magnitude of autoconversion, a model representation of precipitation formation via collisions among cloud droplets. This provides a method to use satellite observations to constrain cloud lifetime effects in global climate models. S{sub pop} in marine clouds estimated from CloudSat, MODIS and AMSR-E observations is substantially lower than that from global climate models and suggests a liquid water path increase of less than 5% from doubled cloud condensation nuclei concentrations. This implies a substantially smaller impact on shortwave cloud radiative forcing (SWCF) over ocean due to aerosol indirect effects than simulated by current global climate models (a reduction by one-third for one of the conventional aerosol-climate models). Further work is needed to quantify the uncertainties in satellite-derived estimates of S{sub pop} and to examine S{sub pop} in high-resolution models.

Wang, Minghuai; Ghan, Steven J.; Liu, Xiaohong; Ecuyer, Tristan L.; Zhang, Kai; Morrison, H.; Ovchinnikov, Mikhail; Easter, Richard C.; Marchand, Roger; Chand, Duli; Qian, Yun; Penner, Joyce E.

2012-08-15T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
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161

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

SciTech Connect (OSTI)

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.

Lechman, Jeremy B.

2010-10-01T23:59:59.000Z

162

Aerosol tests conducted at Aberdeen Proving Grounds MD.  

SciTech Connect (OSTI)

Test data are reported that demonstrate the deposition from a spray dispersion system (Illinois Tool Works inductively charging rotary atomization nozzle) for application of decontamination solution to various surfaces in the passenger cabin of a Boeing 737 aircraft. The decontamination solution (EnviroTru) was tagged with a known concentration of fluorescein permitting determination of both airborne decontaminant concentration and surface deposited decontaminant solution so that the effective deposition rates and surface coverage could be determined and correlated with the amount of material sprayed. Six aerosol dispersion tests were conducted. In each test, aluminum foil deposition coupons were set out throughout the passenger area and the aerosol was dispersed. The aerosol concentration was measured with filter samplers as well as with optical techniques Average aerosol deposition ranged from 3 to 15 grams of decontamination solution per square meter. Some disagreement was observed between various instruments utilizing different measurement principles. These results demonstrate a potentially effective method to disperse decontaminant to interior surfaces of a passenger aircraft.

Brockmann, John E.; Lucero, Daniel A.; Servantes, Brandon Lee; Hankins, Matthew Granholm

2012-06-01T23:59:59.000Z

163

FY 2011 Second Quarter: Demonstration of New Aerosol Measurement Verification Testbed for Present-Day Global Aerosol Simulations  

SciTech Connect (OSTI)

The regional-scale Weather Research and Forecasting (WRF) model is being used by a DOE Earth System Modeling (ESM) project titled “Improving the Characterization of Clouds, Aerosols and the Cryosphere in Climate Models” to evaluate the performance of atmospheric process modules that treat aerosols and aerosol radiative forcing in the Arctic. We are using a regional-scale modeling framework for three reasons: (1) It is easier to produce a useful comparison to observations with a high resolution model; (2) We can compare the behavior of the CAM parameterization suite with some of the more complex and computationally expensive parameterizations used in WRF; (3) we can explore the behavior of this parameterization suite at high resolution. Climate models like the Community Atmosphere Model version 5 (CAM5) being used within the Community Earth System Model (CESM) will not likely be run at mesoscale spatial resolutions (10–20 km) until 5–10 years from now. The performance of the current suite of physics modules in CAM5 at such resolutions is not known, and current computing resources do not permit high-resolution global simulations to be performed routinely. We are taking advantage of two tools recently developed under PNNL Laboratory Directed Research and Development (LDRD) projects for this activity. The first is the Aerosol Modeling Testbed (Fast et al., 2011b), a new computational framework designed to streamline the process of testing and evaluating aerosol process modules over a range of spatial and temporal scales. The second is the CAM5 suite of physics parameterizations that have been ported into WRF so that their performance and scale dependency can be quantified at mesoscale spatial resolutions (Gustafson et al., 2010; with more publications in preparation).

Koch, D

2011-03-20T23:59:59.000Z

164

Vapor scavenging by atmospheric aerosol particles  

SciTech Connect (OSTI)

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.

Andrews, E.

1996-05-01T23:59:59.000Z

165

A Physically Based Framework for Modelling the Organic Fractionation of Sea Spray Aerosol from Bubble Film Langmuir Equilibria  

SciTech Connect (OSTI)

The presence of a large fraction of organic matter in primary sea spray aerosol (SSA) can strongly affect its cloud condensation nuclei activity and interactions with marine clouds. Global climate models require new parameterizations of the SSA composition in order to improve the representation of these processes. Existing proposals for such a parameterization use remotely-sensed chlorophyll-a concentrations as a proxy for the biogenic contribution to the aerosol. However, both observations and theoretical considerations suggest that existing relationships with chlorophyll-a, derived from observations at only a few locations, may not be representative for all ocean regions. We introduce a novel framework for parameterizing the fractionation of marine organic matter into SSA based on a competitive Langmuir adsorption equilibrium at bubble surfaces. Marine organic matter is partitioned into classes with differing molecular weights, surface excesses, and Langmuir adsorption parameters. The classes include a lipid-like mixture associated with labile dissolved organic carbon (DOC), a polysaccharide-like mixture associated primarily with semi-labile DOC, a protein-like mixture with concentrations intermediate between lipids and polysaccharides, a processed mixture associated with recalcitrant surface DOC, and a deep abyssal humic-like mixture. Box model calculations have been performed for several cases of organic adsorption to illustrate the underlying concepts. We then apply the framework to output from a global marine biogeochemistry model, by partitioning total dissolved organic carbon into several classes of macromolecule. Each class is represented by model compounds with physical and chemical properties based on existing laboratory data. This allows us to globally map the predicted organic mass fraction of the nascent submicron sea spray aerosol. Predicted relationships between chlorophyll-\\textit{a} and organic fraction are similar to existing empirical parameterizations, but can vary between biologically productive and non-productive regions, and seasonally within a given region. Major uncertainties include the bubble film thickness at bursting and the variability of organic surfactant activity in the ocean, which is poorly constrained. In addition, marine colloids and cooperative adsorption of polysaccharides may make important contributions to the aerosol, but are not included here. This organic fractionation framework is an initial step towards a closer linking of ocean biogeochemistry and aerosol chemical composition in Earth system models. Future work should focus on improving constraints on model parameters through new laboratory experiments or through empirical fitting to observed relationships in the real ocean and atmosphere, as well as on atmospheric implications of the variable composition of organic matter in sea spray.

Burrows, Susannah M.; Ogunro, O.; Frossard, Amanda; Russell, Lynn M.; Rasch, Philip J.; Elliott, S.

2014-12-19T23:59:59.000Z

166

Review of models applicable to accident aerosols  

SciTech Connect (OSTI)

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.

Glissmeyer, J.A.

1983-07-01T23:59:59.000Z

167

Stratospheric Aerosol Geoengineering ALAN ROBOCK  

E-Print Network [OSTI]

Stratospheric Aerosol Geoengineering ALAN ROBOCK ABSTRACT In response to global warming, one suggested geoengineering response involves creating a cloud of particles in the stratosphere to reflect some, the volcano analog also warns against geoengineering because of responses such as ozone depletion, regional

Robock, Alan

168

Residence times of fine tropospheric aerosols as determined by {sup 210}Pb progeny.  

SciTech Connect (OSTI)

Fine tropospheric aerosols can play important roles in the radiative balance of the atmosphere. The fine aerosols can act directly to cool the atmosphere by scattering incoming solar radiation, as well as indirectly by serving as cloud condensation nuclei. Fine aerosols, particularly carbonaceous soots, can also warm the atmosphere by absorbing incoming solar radiation. In addition, aerosols smaller than 2.5 {micro}m have recently been implicated in the health effects of air pollution. Aerosol-active radioisotopes are ideal tracers for the study of atmospheric transport processes. The source terms of these radioisotopes are relatively well known, and they are removed from the atmosphere only by radioactive decay or by wet or dry deposition of the host aerosol. The progeny of the primordial radionuclide {sup 238}U are of particular importance to atmospheric studies. Uranium-238 is common throughout Earth's crust and decays to the inert gas {sup 222}Rn, which escapes into the atmosphere. Radon-222 decays by the series of alpha and beta emissions shown in Figure 1 to the long-lived {sup 210}Pb. Once formed, {sup 210}Pb becomes attached to aerosol particles with average attachment times of 40 s to 3 min.

Marley, N. A.; Gaffney, J. S.; Drayton, P. J.; Cunningham, M. M.; Mielcarek, C.; Ravelo, R.; Wagner, C.

1999-10-05T23:59:59.000Z

169

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

ScienceCinema (OSTI)

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.

None

2014-06-03T23:59:59.000Z

170

Factors affecting the indoor concentrations of carbonaceous aerosols of outdoor origin  

SciTech Connect (OSTI)

A field study was conducted in an unoccupied single story residence in Clovis, California to provide data to address issues important to assess the indoor exposure to particles of outdoor origin. Measurements of black and organic carbonaceous aerosols were performed using a variety of methods, resulting in both near real-time measurements as well as integrated filter based measurements. Comparisons of the different measurement methods show that it is crucial to account for gas phase adsorption artifacts when measuring organic carbon (OC). Measured concentrations affected by the emissions of organic compounds sorbed to indoor surfaces imply a higher degree of infiltration of outdoor organic carbon aerosols into the indoor environment for our unoccupied house. Analysis of the indoor and outdoor data for black carbon (BC) aerosols show that, on average, the indoor concentration of black carbon aerosols behaves in a similar manner to sulfate aerosols. In contrast, organic carbon aerosols are subject to chemical transformations indoors that, for our unoccupied home, resulted in lower indoor OC concentrations than would be expected by physical loss mechanisms alone. These results show that gas to particle partitioning of organic compounds, as well as gas to surface interactions within the residence, are an important process governing the indoor concentration to OC aerosols of outdoor origin.

Lunden, Melissa M.; Kirchstetter, Thomas W.; Thatcher, Tracy L.; Hering, Susanne V.; Brown, Nancy J.

2007-06-25T23:59:59.000Z

171

Microsoft Word - Aerosol Working Group_Norfolk 2008.doc  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces andMappingENVIRONMENTAL IMPACT STATEMENTbelow).A NewACCOMMODATES ALL88ARM

172

LESSONS LEARNED IN AEROSOL MONITORING WITH THE RASA  

SciTech Connect (OSTI)

The Radionuclide Aerosol Sampler/Analyzer (RASA) is an automated aerosol collection and analysis system designed by Pacific Northwest National Laboratory (PNNL) in the 1990's and is deployed in several locations around the world as part of the International Monitoring System (IMS) required under the Comprehensive Nuclear-Test-Ban Treaty (CTBT). The RASA operates unattended, save for regularly scheduled maintenance, iterating samples through a three-step process on a 24-hour interval. In its 15-year history, much has been learned from the operation and maintenance of the RASA that can benefit engineering updates or future aerosol systems. On 11 March 2011, a 9.0 magnitude earthquake and tsunami rocked the eastern coast of Japan, resulting in power loss and cooling failures at the Daiichi nuclear power plants in Fukushima Prefecture. Aerosol collections were conducted with the RASA in Richland, WA. We present a summary of the lessons learned over the history of the RASA, including lessons taken from the Fukushima incident, regarding the RASA IMS stations operated by the United States.

Forrester, Joel B.; Bowyer, Ted W.; Carty, Fitz; Comes, Laura; Eslinger, Paul W.; Greenwood, Lawrence R.; Haas, Derek A.; Hayes, James C.; Kirkham, Randy R.; Lepel, Elwood A.; Litke, Kevin E.; Miley, Harry S.; Morris, Scott J.; Schrom, Brian T.; Van Davelaar, Peter; Woods, Vincent T.

2011-09-14T23:59:59.000Z

173

Fission-product aerosol sampling system for LWR experiments in the TREAT reactor  

SciTech Connect (OSTI)

This work summarizes the design and collection characteristics of a fission-product aerosol sampling system that was developed for a series of light water reactor (LWR) source-term experiments under consideration for performance in 1984 at Argonne National Laboratory's TREAT reactor. These tests would be performed using a bundle of four preirradiated, Zircaloy-clad LWR fuel pins. In these tests, fuel pin integrity would be breached under various simulated accident conditions. The aerosol sampling system was designed to efficiently extract and collect these aerosols such that time-averaged aerosol size distributions, number concentrations and mass loadings could be determined accurately for each experiment, using a combination of real-time and time-interval measurements and post-test analytical techniques. The entire system also was designed to be disassembled remotely because of potentially high levels of radioactivity.

Dunn, P.F.

1983-01-01T23:59:59.000Z

174

Spent fuel sabotage aerosol test program :FY 2005-06 testing and aerosol data summary.  

SciTech Connect (OSTI)

This multinational, multi-phase spent fuel sabotage test program is quantifying the aerosol particles produced when the products of a high energy density device (HEDD) interact with and explosively particulate test rodlets that contain pellets of either surrogate materials or actual spent fuel. This program has been underway for several years. This program provides source-term data that are relevant to some sabotage scenarios in relation to spent fuel transport and storage casks, and associated risk assessments. This document focuses on an updated description of the test program and test components for all work and plans made, or revised, primarily during FY 2005 and about the first two-thirds of FY 2006. It also serves as a program status report as of the end of May 2006. We provide details on the significant findings on aerosol results and observations from the recently completed Phase 2 surrogate material tests using cerium oxide ceramic pellets in test rodlets plus non-radioactive fission product dopants. Results include: respirable fractions produced; amounts, nuclide content, and produced particle size distributions and morphology; status on determination of the spent fuel ratio, SFR (the ratio of respirable particles from real spent fuel/respirables from surrogate spent fuel, measured under closely matched test conditions, in a contained test chamber); and, measurements of enhanced volatile fission product species sorption onto respirable particles. We discuss progress and results for the first three, recently performed Phase 3 tests using depleted uranium oxide, DUO{sub 2}, test rodlets. We will also review the status of preparations and the final Phase 4 tests in this program, using short rodlets containing actual spent fuel from U.S. PWR reactors, with both high- and lower-burnup fuel. These data plus testing results and design are tailored to support and guide, follow-on computer modeling of aerosol dispersal hazards and radiological consequence assessments. This spent fuel sabotage--aerosol test program, performed primarily at Sandia National Laboratories, with support provided by both the U.S. Department of Energy and the Nuclear Regulatory Commission, had significant inputs from, and is strongly supported and coordinated by both the U.S. and international program participants in Germany, France, and the U.K., as part of the international Working Group for Sabotage Concerns of Transport and Storage Casks, WGSTSC.

Gregson, Michael Warren; Brockmann, John E.; Nolte, O. (Fraunhofer institut fur toxikologie und experimentelle Medizin, Germany); Loiseau, O. (Institut de radioprotection et de Surete Nucleaire, France); Koch, W. (Fraunhofer institut fur toxikologie und experimentelle Medizin, Germany); Molecke, Martin Alan; Autrusson, Bruno (Institut de radioprotection et de Surete Nucleaire, France); Pretzsch, Gunter Guido (Gesellschaft fur anlagen- und Reaktorsicherheit, Germany); Billone, M. C. (Argonne National Laboratory, USA); Lucero, Daniel A.; Burtseva, T. (Argonne National Laboratory, USA); Brucher, W (Gesellschaft fur anlagen- und Reaktorsicherheit, Germany); Steyskal, Michele D.

2006-10-01T23:59:59.000Z

175

DO AEROSOLS CHANGE CLOUD COVER AND AFFECT CLIMATE?  

E-Print Network [OSTI]

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

Schwartz, Stephen E.

176

Surveillance Guides - Work Control Process  

Broader source: Energy.gov (indexed) [DOE]

in accordance with contractual mechanisms such as Maintenance Implementation Plans, Conduct of Operations Implementation Plans, and the Integrated Safety Management System...

177

Aerosol cluster impact and break-up : II. Atomic and Cluster Scale Models.  

SciTech Connect (OSTI)

Understanding the interaction of aerosol particle clusters/flocs with surfaces is an area of interest for a number of processes in chemical, pharmaceutical, and powder manufacturing as well as in steam-tube rupture in nuclear power plants. Developing predictive capabilities for these applications involves coupled phenomena on multiple length and timescales from the process macroscopic scale ({approx}1m) to the multi-cluster interaction scale (1mm-0.1m) to the single cluster scale ({approx}1000 - 10000 particles) to the particle scale (10nm-10{micro}m) interactions, and on down to the sub-particle, atomic scale interactions. The focus of this report is on the single cluster scale; although work directed toward developing better models of particle-particle interactions by considering sub-particle scale interactions and phenomena is also described. In particular, results of mesoscale (i.e., particle to single cluster scale) discrete element method (DEM) simulations for aerosol cluster impact with rigid walls are presented. The particle-particle interaction model is based on JKR adhesion theory and is implemented as an enhancement to the granular package in the LAMMPS code. The theory behind the model is outlined and preliminary results are shown. Additionally, as mentioned, results from atomistic classical molecular dynamics simulations are also described as a means of developing higher fidelity models of particle-particle interactions. Ultimately, the results from these and other studies at various scales must be collated to provide systems level models with accurate 'sub-grid' information for design, analysis and control of the underlying systems processes.

Lechman, Jeremy B.; Takato, Yoichi (State University of New York at Buffalo, Buffalo, NY)

2010-09-01T23:59:59.000Z

178

Scanning Transmission X-ray Microscopy: Applications in Atmospheric Aerosol Research  

SciTech Connect (OSTI)

Scanning transmission x-ray microscopy (STXM) combines x-ray microscopy and near edge x-ray absorption fine structure spectroscopy (NEXAFS). This combination provides spatially resolved bonding and oxidation state information. While there are reviews relevant to STXM/NEXAFS applications in other environmental fields (and magnetic materials) this chapter focuses on atmospheric aerosols. It provides an introduction to this technique in a manner approachable to non-experts. It begins with relevant background information on synchrotron radiation sources and a description of NEXAFS spectroscopy. The bulk of the chapter provides a survey of STXM/NEXAFS aerosol studies and is organized according to the type of aerosol investigated. The purpose is to illustrate the current range and recent growth of scientific investigations employing STXM-NEXAFS to probe atmospheric aerosol morphology, surface coatings, mixing states, and atmospheric processing.

Moffet, Ryan C.; Tivanski, Alexei V.; Gilles, Mary K.

2011-01-20T23:59:59.000Z

179

Low-temperature Bessel beam trap for single submicrometer aerosol particle studies  

SciTech Connect (OSTI)

We report on a new instrument for single aerosol particle studies at low temperatures that combines an optical trap consisting of two counter-propagating Bessel beams (CPBBs) and temperature control down to 223 K (?50?°C). The apparatus is capable of capturing and stably trapping individual submicrometer- to micrometer-sized aerosol particles for up to several hours. First results from studies of hexadecane, dodecane, and water aerosols reveal that we can trap and freeze supercooled droplets ranging in size from ?450 nm to 5500 nm (radius). We have conducted homogeneous and heterogeneous freezing experiments, freezing-melting cycles, and evaporation studies. To our knowledge, this is the first reported observation of the freezing process for levitated single submicrometer-sized droplets in air using optical trapping techniques. These results show that a temperature-controlled CPBB trap is an attractive new method for studying phase transitions of individual submicrometer aerosol particles.

Lu, Jessica W.; Chasovskikh, Egor; Stapfer, David [Laboratory of Physical Chemistry, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich (Switzerland); Isenor, Merrill; Signorell, Ruth [Laboratory of Physical Chemistry, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich (Switzerland); Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1 (Canada)

2014-09-01T23:59:59.000Z

180

Photoacoustic optical properties at UV, VIS, and near IR wavelengths for laboratory generated and winter time ambient urban aerosols  

SciTech Connect (OSTI)

We present the laboratory and ambient photoacoustic (PA) measurement of aerosol light absorption coefficients at ultraviolet wavelength (i.e., 355 nm) and compare with measurements at 405, 532, 870, and 1047 nm. Simultaneous measurements of aerosol light scattering coefficients were achieved by the integrating reciprocal nephelometer within the PA's acoustic resonator. Absorption and scattering measurements were carried out for various laboratory generated aerosols, including salt, incense, and kerosene soot to evaluate the instrument calibration and gain insight on the spectral dependence of aerosol light absorption and scattering. Ambient measurements were obtained in Reno, Nevada, between 18 December 2009 and 18 January 2010. The measurement period included days with and without strong ground level temperature inversions, corresponding to highly polluted (freshly emitted aerosols) and relatively clean (aged aerosols) conditions. Particulate matter (PM) concentrations were measured and analyzed with other tracers of traffic emissions. The temperature inversion episodes caused very high concentration of PM{sub 2.5} and PM{sub 10} (particulate matter with aerodynamic diameters less than 2.5 {mu}m and 10 {mu}m, respectively) and gaseous pollutants: carbon monoxide (CO), nitric oxide (NO), and nitrogen dioxide (NO{sub 2}). The diurnal change of absorption and scattering coefficients during the polluted (inversion) days increased approximately by a factor of two for all wavelengths compared to the clean days. The spectral variation in aerosol absorption coefficients indicated a significant amount of absorbing aerosol from traffic emissions and residential wood burning. The analysis of single scattering albedo (SSA), Angstrom exponent of absorption (AEA), and Angstrom exponent of scattering (AES) for clean and polluted days provides evidences that the aerosol aging and coating process is suppressed by strong temperature inversion under cloudy conditions. In general, measured UV absorption coefficients were found to be much larger for biomass burning aerosol than for typical ambient aerosols.

Gyawali, Madhu S.; Arnott, W. Patrick; Zaveri, Rahul A.; Song, Chen; Moosmuller, H.; Liu, Li; Mishchenko, M.; Chen, L-W A.; Green, M.; Watson, J. G.; Chow, J. C.

2012-03-08T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

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

182

Direct and semidirect aerosol effects of southern African biomass burning aerosol  

E-Print Network [OSTI]

Direct and semidirect aerosol effects of southern African biomass burning aerosol Naoko Sakaeda,1 2011; published 21 June 2011. [1] Direct and semidirect radiative effects of biomass burning aerosols static stability. Over the entire region the overall TOA radiative effect from the biomass burning

Wood, Robert

183

Investigation of Aerosol Indirect Effects using a Cumulus Microphysics Parameterization in a Regional Climate Model  

SciTech Connect (OSTI)

A new Zhang and McFarlane (ZM) cumulus scheme includes a two-moment cloud microphysics parameterization for convective clouds. This allows aerosol effects to be investigated more comprehensively by linking aerosols with microphysical processes in both stratiform clouds that are explicitly resolved and convective clouds that are parameterized in climate models. This new scheme is implemented in the Weather Research and Forecasting (WRF) model, which is coupled with the physics and aerosol packages from the Community Atmospheric Model version 5 (CAM5). A test case of July 2008 during the East Asian summer monsoon is selected to evaluate the performance of the new ZM scheme and to investigate aerosol effects on monsoon precipitation. The precipitation and radiative fluxes simulated by the new ZM scheme show a better agreement with observations compared to simulations with the original ZM scheme that does not include convective cloud microphysics and aerosol convective cloud interactions. Detailed analysis suggests that an increase in detrained cloud water and ice mass by the new ZM scheme is responsible for this improvement. To investigate precipitation response to increased anthropogenic aerosols, a sensitivity experiment is performed that mimics a clean environment by reducing the primary aerosols and anthropogenic emissions to 30% of that used in the control simulation of a polluted environment. The simulated surface precipitation is reduced by 9.8% from clean to polluted environment and the reduction is less significant when microphysics processes are excluded from the cumulus clouds. Ensemble experiments with ten members under each condition (i.e., clean and polluted) indicate similar response of the monsoon precipitation to increasing aerosols.

Lim, Kyo-Sun; Fan, Jiwen; Leung, Lai-Yung R.; Ma, Po-Lun; Singh, Balwinder; Zhao, Chun; Zhang, Yang; Zhang, Guang; Song, Xiaoliang

2014-01-29T23:59:59.000Z

184

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,...

185

Separating Cloud Forming Nuclei from Interstitial Aerosol  

SciTech Connect (OSTI)

It has become important to characterize the physicochemical properties of aerosol that have initiated the warm and ice clouds. The data is urgently needed to better represent the aerosol-cloud interaction mechanisms in the climate models. The laboratory and in-situ techniques to separate precisely the aerosol particles that act as cloud condensation nuclei (CCN) and ice nuclei (IN), termed as cloud nuclei (CN) henceforth, have become imperative in studying aerosol effects on clouds and the environment. This review summarizes these techniques, design considerations, associated artifacts and challenges, and briefly discusses the need for improved designs to expand the CN measurement database.

Kulkarni, Gourihar R.

2012-09-12T23:59:59.000Z

186

Indirect and Semi-Direct Aerosol Campaign  

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

October? 2. To what extent do the different properties of the Arctic aerosol during April produce differences in clouds? * Do the more polluted conditions during April in the...

187

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...

188

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...

189

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...

190

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,...

191

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,...

192

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...

193

The Indirect and Semi-Direct Aerosol Campaign  

ScienceCinema (OSTI)

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

Ghan, Steve

2014-06-12T23:59:59.000Z

194

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...

195

The Indirect and Semi-Direct Aerosol Campaign  

SciTech Connect (OSTI)

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

Ghan, Steve

2014-03-24T23:59:59.000Z

196

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...

197

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...

198

Aerosol Composition and Source Apportionment in the Mexico City...  

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

Aerosol Composition and Source Apportionment in the Mexico City Metropolitan Area with PIXEPESASTIM and Multivariate Analysis. Aerosol Composition and Source Apportionment in the...

199

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...

200

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...

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Optical, physical, and chemical properties of springtime aerosol...  

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

Optical, physical, and chemical properties of springtime aerosol over Barrow Alaska in 2008. Optical, physical, and chemical properties of springtime aerosol over Barrow Alaska in...

202

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...

203

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;...

204

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;...

205

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...

206

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,...

207

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...

208

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...

209

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

SciTech Connect (OSTI)

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.

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

210

Aerosol particle transport modeling for preclosure safety studies of nuclear waste repositories  

SciTech Connect (OSTI)

An important concern for preclosure safety analysis of a nuclear waste repository is the potential release to the environment of respirable aerosol particles. Such particles, less than 10 {mu}m in aerodynamic diameter, may have significant adverse health effects if inhaled. To assess the potential health effects of these particles, it is not sufficient to determine the mass fraction of respirable aerosol. The chemical composition of the particles is also of importance since different radionuclides may pose vastly different health hazards. Thus, models are needed to determine under normal and accident conditions the particle size and the chemical composition distributions of aerosol particles as a function of time and of position in the repository. In this work a multicomponent sectional aerosol model is used to determine the aerosol particle size and composition distributions in the repository. A range of aerosol mass releases with varying mean particle sizes and chemical compositions is used to demonstrate the sensitivities and uncertainties of the model. Decontamination factors for some locations in the repository are presented. 8 refs., 1 tab.

Gelbard, F. [Sandia National Labs., Albuquerque, NM (USA)

1989-01-01T23:59:59.000Z

211

Heterogeneous Chemistry: Understanding Aerosol/Oxidant Interactions  

SciTech Connect (OSTI)

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.

Joyce E. Penner

2005-03-14T23:59:59.000Z

212

Characterization of aerosols produced by surgical procedures  

SciTech Connect (OSTI)

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.

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

213

Observations of the first aerosol indirect effect in shallow cumuli  

SciTech Connect (OSTI)

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.

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

2011-02-08T23:59:59.000Z

214

DRAFT, last update 5 January 2012 Aerosol cloud-mediated radiative forcing: highly uncertain and  

E-Print Network [OSTI]

phase and ice processes. Respectively, the parameterization of these processes for GCMs is further away and aerosol parameterizations, but intense research efforts aimed at improving the realism of cloud lower than for the shallow clouds, as the deep clouds are much more complicated, because mixed phase

Wood, Robert

215

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

SciTech Connect (OSTI)

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.

Deepak, A.

1980-05-01T23:59:59.000Z

216

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

SciTech Connect (OSTI)

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.

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

2011-11-01T23:59:59.000Z

217

PARAGON - An Integrated Approach for Characterizing Aerosol Climate Impacts and Environmental Interactions  

SciTech Connect (OSTI)

Aerosols exert myriad influences on the Earth?s environment and climate and on human health. The complexity of aerosol-related processes requires that information gathered to improve our understanding of climate change must originate from multiple sources, and that effective strategies for data integration need to be established. Currently, the aerosol community lacks the necessary tools and infrastructure to reap maximum scientific benefit from a vast array of observed and modeled data. Spatial and temporal sampling differences among a diverse set of sensors, nonuniform data qualities, aerosol mesoscale variabilities, and difficulties in separating cloud effects are some of the challenges that need to be addressed. A sustained, long-term program also requires maintaining consistently well-understood accuracies as measurement approaches evolve and improve. Achieving a comprehensive understanding of how aerosol physical, chemical, and radiative processes impact the Earth system can only be achieved through a multidisciplinary, interagency, and international initiative capable of dealing with these issues. A systematic approach, capitalizing on modern measurement and modeling techniques, geospatial statistics methodologies, and high-performance information technologies can provide the necessary machinery to support this objective. We outline a framework for integrating and interpreting observations and models and establishing an accurate, consistent and cohesive long-term record, following a strategy whereby information and tools of progressively greater sophistication are incorporated as problems of increasing complexity are tackled. This concept is named the Progressive Aerosol Retrieval and Assimilation Global Observing Network (PARAGON). To encompass the breadth of effort required, we present a set of recommendations dealing with data interoperability, integration, synergy, summarization and mining, model evaluation, calibration and validation, augmentation of surface and in situ measurements, advances in passive and active remote sensing, and design of satellite missions. Without an initiative of this nature, the scientific and policy communities will continue to struggle with understanding the quantitative impact of complex aerosol processes on regional and global climate change and air quality.

Diner, David J.; Ackerman, Thomas P.; Anderson, Theodore L.; Bosenberg, Jens; Braverman, Amy J.; Charlson, Robert J.; Collins, William D.; Davies, Roger; Holben, B. N.; Hostetler, Chris A.; Kahn, Ralph A.; Martonchik, John V.; Menzies, Robert T.; Miller, Mark A.; Ogren, J. A.; Penner, Joyce E.; Rasch, P; Schwartz, Stephen E.; Seinfeld, John H.; Stephens, Graeme L.; Torres, Omar; Travis, Larry D.; Wielicki, Bruce A.; Yu, Bin

2004-10-01T23:59:59.000Z

218

Spent fuel sabotage aerosol ratio program : FY 2004 test and data summary.  

SciTech Connect (OSTI)

This multinational, multi-phase spent fuel sabotage test program is quantifying the aerosol particles produced when the products of a high energy density device (HEDD) interact with and explosively particulate test rodlets that contain pellets of either surrogate materials or actual spent fuel. This program has been underway for several years. This program provides data that are relevant to some sabotage scenarios in relation to spent fuel transport and storage casks, and associated risk assessments. The program also provides significant technical and political benefits in international cooperation. We are quantifying the Spent Fuel Ratio (SFR), the ratio of the aerosol particles released from HEDD-impacted actual spent fuel to the aerosol particles produced from surrogate materials, measured under closely matched test conditions, in a contained test chamber. In addition, we are measuring the amounts, nuclide content, size distribution of the released aerosol materials, and enhanced sorption of volatile fission product nuclides onto specific aerosol particle size fractions. These data are the input for follow-on modeling studies to quantify respirable hazards, associated radiological risk assessments, vulnerability assessments, and potential cask physical protection design modifications. This document includes an updated description of the test program and test components for all work and plans made, or revised, during FY 2004. It also serves as a program status report as of the end of FY 2004. All available test results, observations, and aerosol analyses plus interpretations--primarily for surrogate material Phase 2 tests, series 2/5A through 2/9B, using cerium oxide sintered ceramic pellets are included. Advanced plans and progress are described for upcoming tests with unirradiated, depleted uranium oxide and actual spent fuel test rodlets. This spent fuel sabotage--aerosol test program is coordinated with the international Working Group for Sabotage Concerns of Transport and Storage Casks (WGSTSC) and supported by both the U.S. Department of Energy and the Nuclear Regulatory Commission.

Brucher, Wenzel (Gesellschaft fur Anlagen- und Reaktorsicherheit, Germany); Koch, Wolfgang (Fraunhofer Institut fur Toxikologie und Experimentelle Medizin, Germany); Pretzsch, Gunter Guido (Gesellschaft fur Anlagen- und Reaktorsicherheit, Germany); Loiseau, Olivier (Institut de Radioprotection et de Surete Nucleaire, France); Mo, Tin (U.S. Nuclear Regulatory Commission, Washington, DC); Billone, Michael C. (Argonne National Laboratory, Argonne, IL); Autrusson, Bruno A. (Institut de Radioprotection et de Surete Nucleaire, France); Young, F. I. (U.S. Nuclear Regulatory Commission, Washington, DC); Coats, Richard Lee; Burtseva, Tatiana (Argonne National Laboratory, Argonne, IL); Luna, Robert Earl; Dickey, Roy R.; Sorenson, Ken Bryce; Nolte, Oliver (Fraunhofer Institut fur Toxikologie und Experimentelle Medizin, Germany); Thompson, Nancy Slater (U.S. Department of Energy, Washington, DC); Hibbs, Russell S. (U.S. Department of Energy, Washington, DC); Gregson, Michael Warren; Lange, Florentin (Gesellschaft fur Anlagen- und Reaktorsicherheit, Germany); Molecke, Martin Alan; Tsai, Han-Chung (Argonne National Laboratory, Argonne, IL)

2005-07-01T23:59:59.000Z

219

ENCAPSULATION EFFECTS ON CARBONACEOUS AEROSOL LIGHT ABSORPTION  

E-Print Network [OSTI]

ENCAPSULATION EFFECTS ON CARBONACEOUS AEROSOL LIGHT ABSORPTION Arthur Sedlacek, Brookhaven National of aerosol absorption on direct radiative forcing is still an active area of research, in part, because. This poster presents data on black carbon (BC) light absorption measured by Photothermal Interferometry

220

2, 12871315, 2002 Aerosol sources and  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

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While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

6, 1217912197, 2006 Aerosol formation in  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

222

6, 32653319, 2006 Study aerosol with  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

223

Small-Scale Spray Releases: Additional Aerosol Test Results  

SciTech Connect (OSTI)

One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. To expand the data set upon which the WTP accident and safety analyses were based, an aerosol spray leak testing program was conducted by Pacific Northwest National Laboratory (PNNL). PNNL’s test program addressed two key technical areas to improve the WTP methodology (Larson and Allen 2010). The first technical area was to quantify the role of slurry particles in small breaches where slurry particles may plug the hole and prevent high-pressure sprays. The results from an effort to address this first technical area can be found in Mahoney et al. (2012a). The second technical area was to determine aerosol droplet size distribution and total droplet volume from prototypic breaches and fluids, including sprays from larger breaches and sprays of slurries for which literature data are largely absent. To address the second technical area, the testing program collected aerosol generation data at two scales, commonly referred to as small-scale and large-scale. The small-scale testing and resultant data are described in Mahoney et al. (2012b) and the large-scale testing and resultant data are presented in Schonewill et al. (2012). In tests at both scales, simulants were used to mimic the relevant physical properties projected for actual WTP process streams.

Schonewill, Philip P.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, G. N.; Mahoney, Lenna A.; Tran, Diana N.; Burns, Carolyn A.; Kurath, Dean E.

2013-08-01T23:59:59.000Z

224

Large-Scale Spray Releases: Additional Aerosol Test Results  

SciTech Connect (OSTI)

One of the events postulated in the hazard analysis for the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak event involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids that behave as a Newtonian fluid. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and in processing facilities across the DOE complex. To expand the data set upon which the WTP accident and safety analyses were based, an aerosol spray leak testing program was conducted by Pacific Northwest National Laboratory (PNNL). PNNL’s test program addressed two key technical areas to improve the WTP methodology (Larson and Allen 2010). The first technical area was to quantify the role of slurry particles in small breaches where slurry particles may plug the hole and prevent high-pressure sprays. The results from an effort to address this first technical area can be found in Mahoney et al. (2012a). The second technical area was to determine aerosol droplet size distribution and total droplet volume from prototypic breaches and fluids, including sprays from larger breaches and sprays of slurries for which literature data are mostly absent. To address the second technical area, the testing program collected aerosol generation data at two scales, commonly referred to as small-scale and large-scale testing. The small-scale testing and resultant data are described in Mahoney et al. (2012b), and the large-scale testing and resultant data are presented in Schonewill et al. (2012). In tests at both scales, simulants were used to mimic the relevant physical properties projected for actual WTP process streams.

Daniel, Richard C.; Gauglitz, Phillip A.; Burns, Carolyn A.; Fountain, Matthew S.; Shimskey, Rick W.; Billing, Justin M.; Bontha, Jagannadha R.; Kurath, Dean E.; Jenks, Jeromy WJ; MacFarlan, Paul J.; Mahoney, Lenna A.

2013-08-01T23:59:59.000Z

225

ARM - Field Campaign - Aerosol IOP  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered‰PNGExperience4AJ01)3, 2010SeptemberInfrared SpectralgovCampaignsAerosol IOP

226

Plutonium working group report on environmental, safety and health vulnerabilities associated with the Department`s plutonium storage. Volume 2, Appendix A: Process and protocol  

SciTech Connect (OSTI)

This appendix contains documentation prepared by the Plutonium ES and H Vulnerability Working Group for conducting the Plutonium ES and H Vulnerability Assessment and training the assessment teams. It has the following five parts. (1) The Project Plan describes the genesis of the project, sets forth the goals, objectives and scope, provides definitions, the projected schedule, and elements of protocol. (2) The Assessment Plan provides a detailed methodology necessary to guide the many professionals who have been recruited to conduct the DOE-wide assessment. It provides guidance on which types and forms of plutonium are to be considered within the scope of the assessment, and lays out the assessment methodology to be used. (3) The memorandum from the Project to Operations Office Managers provides the protocol and direction for participation in the assessment by external stakeholders and members of the public; and the guidance for the physical inspection of plutonium materials in storage. (4) The memorandum from the Project to the assessment teams provides guidance for vulnerability screening criteria, vulnerability evaluation and prioritization process, and vulnerability quantification for prioritization. (5) The Team Training manual was used at the training session held in Colorado Springs on April 19--21, 1994 for all members of the Working Group Assessment Teams and for the leaders of the Site Assessment Teams. The goal was to provide the same training to all of the individuals who would be conducting the assessments, and thereby provide consistency in the conduct of the assessments and uniformity in reporting of the results. The training manual in Section A.5 includes supplemental material provided to the attendees after the meeting.

NONE

1994-09-01T23:59:59.000Z

227

Global observations of desert dust and biomass burning aerosols  

E-Print Network [OSTI]

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.6 Biomass burning over Angola, 09 Sep. 2004 Absorbing Aerosol Index PMD image #12;biomass burning ocean

Graaf, Martin de

228

Work Authorization System  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

To establish a work authorization and control process for work performed by designated site and facility management contractors, and other contractors as determined by the procurement executive, consistent with the budget execution and program evaluation requirements of the Department of Energy's (DOE's) Planning, Programming, Budgeting, and Evaluation process. Cancels DOE O 412.1.

2005-04-21T23:59:59.000Z

229

Work Authorization System  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

To establish a work authorization and control process for work performed by designated site and facility management contractors, and other contractors as determined by the procurement executive, consistent with the budget execution and program evaluation requirements of the Department of Energy's Planning, Programming, Budgeting, and Evaluation process. Admin Chg 1, dated 5-21-2014, cancels DOE O 412.1A.

2005-04-21T23:59:59.000Z

230

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

E-Print Network [OSTI]

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

Tilstra, Gijsbert

231

An Aerosol Condensation Model for Sulfur Trioxide  

SciTech Connect (OSTI)

This document describes a model for condensation of sulfuric acid aerosol given an initial concentration and/or source of gaseous sulfur trioxide (e.g. fuming from oleum). The model includes the thermochemical effects on aerosol condensation and air parcel buoyancy. Condensation is assumed to occur heterogeneously onto a preexisting background aerosol distribution. The model development is both a revisiting of research initially presented at the Fall 2001 American Geophysical Union Meeting [1] and a further extension to provide new capabilities for current atmospheric dispersion modeling efforts [2]. Sulfuric acid is one of the most widely used of all industrial chemicals. In 1992, world consumption of sulfuric acid was 145 million metric tons, with 42.4 Mt (mega-tons) consumed in the United States [10]. In 2001, of 37.5 Mt consumed in the U.S., 74% went into producing phosphate fertilizers [11]. Another significant use is in mining industries. Lawuyi and Fingas [7] estimate that, in 1996, 68% of use was for fertilizers and 5.8% was for mining. They note that H{sub 2}SO{sub 4} use has been and should continue to be very stable. In the United States, the elimination of MTBE (methyl tertiary-butyl ether) and the use of ethanol for gasoline production are further increasing the demand for petroleum alkylate. Alkylate producers have a choice of either a hydrofluoric acid or sulfuric acid process. Both processes are widely used today. Concerns, however, over the safety or potential regulation of hydrofluoric acid are likely to result in most of the growth being for the sulfuric acid process, further increasing demand [11]. The implication of sulfuric acid being a pervasive industrial chemical is that transport is also pervasive. Often, this is in the form of oleum tankers, having around 30% free sulfur trioxide. Although sulfuric acid itself is not a volatile substance, fuming sulfuric acid (referred to as oleum) is [7], the volatile product being sulfur trioxide. Sulfate aerosols and mist may form in the atmosphere on tank rupture. From chemical spill data from 1990-1996, Lawuyi02 and Fingas [7] prioritize sulfuric acid as sixth most serious. During this period, they note 155 spills totaling 13 Mt, out of a supply volume of 3700 Mt. Lawuyi and Fingas [7] summarize information on three major sulfuric acid spills. On 12 February 1984, 93 tons of sulfuric acid were spilled when 14 railroad cars derailed near MacTier, Parry Sound, Ontario. On 13 December 1978, 51 railroad cars derailed near Springhill, Nova Scotia. One car, containing 93% sulfuric acid, ruptured, spilling nearly its entire contents. In July 1993, 20 to 50 tons of fuming sulfuric acid spilled at the General Chemical Corp. plant in Richmond, California, a major industrial center near San Francisco. The release occurred when oleum was being loaded into a nonfuming acid railroad tank car that contained only a rupture disk as a safety device. The tank car was overheated and this rupture disk blew. The resulting cloud of sulfuric acid drifted northeast with prevailing winds over a number of populated areas. More than 3,000 people subsequently sought medical attention for burning eyes, coughing, headaches, and nausea. Almost all were treated and released on the day of the spill. By the day after the release, another 5,000 people had sought medical attention. The spill forced the closure of five freeways in the region as well as some Bay Area Rapid Transit System stations. Apart from corrosive toxicity, there is the additional hazard that the reactions of sulfur trioxide and sulfuric acid vapors with water are extremely exothermic [10, 11]. While the vapors are intrinsically denser than air, there is thus the likelihood of strong, warming-induced buoyancy from reactions with ambient water vapor, water-containing aerosol droplets, and wet environmental surface. Nordin [12] relates just such an occurrence following the Richmond, CA spill, with the plume observed to rise to 300 m. For all practical purposes, sulfur trioxide was the constituent released from the heated tank

Grant, K E

2008-02-07T23:59:59.000Z

232

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

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

Aerosol Campaign: The Impact of Arctic Aerosols on Clouds . Abstract: A comprehensive dataset of microphysical and radiative properties of aerosols and clouds in the arctic...

233

CARES: Carbonaceous Aerosol and Radiative Effects Study Science Plan  

SciTech Connect (OSTI)

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.

Zaveri, RA; Shaw, WJ; Cziczo, DJ

2010-05-27T23:59:59.000Z

234

Capstone Depleted Uranium Aerosols: Generation and Characterization  

SciTech Connect (OSTI)

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.

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

235

The importance of aerosol mixing state and size-resolved composition on CCN concentration and the variation of the importance with atmospheric aging of aerosols  

SciTech Connect (OSTI)

Aerosol microphysics, chemical composition, and CCN concentrations were measured at the T0 urban supersite in Mexico City during Megacity Initiative: Local and Global Research Observations (MILAGRO) in March 2006. The aerosol size distribution and composition often showed strong diurnal variation associated with traffic emissions and aging of aerosols through coagulation and local photochemical production of secondary aerosol species. CCN concentrations (N{sub CCN}) are derived using Kohler theory from the measured aerosol size distribution and various simplified aerosol mixing state and chemical composition, and are compared to concurrent measurements at five supersaturations ranging from 0.11% to 0.35%. The influence of assumed mixing state on calculated N{sub CCN} is examined using both aerosols observed during MILAGRO and representative aerosol types. The results indicate that while ambient aerosols often consist of particles with a wide range of compositions at a given size, N{sub CCN} may be derived within {approx}20% assuming an internal mixture (i.e., particles at a given size are mixtures of all participating species, and have the identical composition) if great majority of particles has an overall {kappa} (hygroscopicity parameter) value greater than 0.1. For a non-hygroscopic particle with a diameter of 100 nm, a 3 nm coating of sulfate or nitrate is sufficient to increase its {kappa} from 0 to 0.1. The measurements during MILAGRO suggest that the mixing of non-hygroscopic primary organic aerosol (POA) and black carbon (BC) particles with photochemically produced hygroscopic species and thereby the increase of their {kappa} to 0.1 take place in a few hours during daytime. This rapid process suggests that during daytime, a few tens of kilometers away for POA and BC sources, N{sub CCN} may be derived with sufficient accuracy by assuming an internal mixture, and using bulk chemical composition. The rapid mixing also indicates that, at least for very active photochemical environments such as Mexico City, a substantially shorter timescale during daytime for the conversion of hydrophobic POA and BC to hydrophilic particles than the 1-2 days used in some global models. The conversion time scale is substantially longer during night. Most POA and BC particles emitted during evening hours likely remain non-hygroscopic until efficiently internally mixed with secondary species in the next morning. The results also suggest that the assumed mixing state strongly impacts calculated N{sub CCN} only when POA and BC represent a large fraction of the total aerosol volume. One of the implications is that while physically unrealistic, external mixtures, which are used in many global models, may also sufficiently predict N{sub CCN} for aged aerosol, as the contribution of non-hygroscopic POA and BC to overall aerosol volume is often substantially reduced due to the condensation of secondary species.

Wang, J.; Cubison, M. J.; Aiken, A. C.; Jimenez, J. L.; Collins, D. R.

2010-05-01T23:59:59.000Z

236

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

SciTech Connect (OSTI)

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.

Richard A. Ferrare; David D. Turner

2011-09-01T23:59:59.000Z

237

Investigation of warm-cloud microphysics using a multi-component cloud model: Interactive effects of the aerosol spectrum. Master's thesis  

SciTech Connect (OSTI)

Clouds, especially low, warm, boundary-layer clouds, play an important role in regulating the earth's climate due to their significant contribution to the global albedo. The radiative effects of individual clouds are controlled largely by cloud microstructure, which is itself sensitive to the concentration and spectral distribution of the atmospheric aerosol. Increases in aerosol particle concentrations from anthropogenic activity could result in increased cloud albedo and global cloudiness, increasing the amount of reflected solar radiation. However, the effects of increased aerosol particle concentrations could be offset by the presence of giant or ultragiant aerosol particles. A one-dimensional, multi-component microphysical cloud model has been used to demonstrate the effects of aerosol particle spectral variations on the microstructure of warm clouds. Simulations performed with this model demonstrate that the introduction of increased concentrations of giant aerosol particles has a destabilizing effect on the cloud microstructure. Also, it is shown that warm-cloud microphysical processes modify the aerosol particle spectrum, favoring the generation of the largest sized particles via the collision-coalescence process. These simulations provide further evidence that the effect of aerosol particles on cloud microstructure must be addressed when considering global climate forecasts.

Zahn, S.G.

1993-12-01T23:59:59.000Z

238

Influence of sky radiance measurement errors on inversion-retrieved aerosol properties  

SciTech Connect (OSTI)

Remote sensing of the atmospheric aerosol is a well-established technique that is currently used for routine monitoring of this atmospheric component, both from ground-based and satellite. The AERONET program, initiated in the 90's, is the most extended network and the data provided are currently used by a wide community of users for aerosol characterization, satellite and model validation and synergetic use with other instrumentation (lidar, in-situ, etc.). Aerosol properties are derived within the network from measurements made by ground-based Sun-sky scanning radiometers. Sky radiances are acquired in two geometries: almucantar and principal plane. Discrepancies in the products obtained following both geometries have been observed and the main aim of this work is to determine if they could be justified by measurement errors. Three systematic errors have been analyzed in order to quantify the effects on the inversion-derived aerosol properties: calibration, pointing accuracy and finite field of view. Simulations have shown that typical uncertainty in the analyzed quantities (5% in calibration, 0.2 Degree-Sign in pointing and 1.2 Degree-Sign field of view) yields to errors in the retrieved parameters that vary depending on the aerosol type and geometry. While calibration and pointing errors have relevant impact on the products, the finite field of view does not produce notable differences.

Torres, B.; Toledano, C.; Cachorro, V. E.; Bennouna, Y. S.; Fuertes, D.; Gonzalez, R.; Frutos, A. M. de [Atmospheric Optics Group (GOA), University of Valladolid, Valladolid (Spain); Berjon, A. J. [Izana Atmospheric Research Center, Meteorological State Agency of Spain (AEMET), Sta. Cruz de Tenerife (Spain); Dubovik, O.; Goloub, P.; Podvin, T.; Blarel, L. [Laboratory of Atmospheric Optics, Universite Lille 1, Villeneuve d'Ascq (France)

2013-05-10T23:59:59.000Z

239

Spectro-Microscopic Measurements of Carbonaceous Aerosol Aging in Central California  

SciTech Connect (OSTI)

Carbonaceous aerosols are responsible for large uncertainties in climate models, degraded visibility, and adverse health effects. The Carbonaceous Aerosols and Radiative Effects Study (CARES) was designed to study carbonaceous aerosols in the natural environment of Central Valley, California, and learn more about their atmospheric formation and aging. This paper presents results from spectro-microscopic measurements of carbonaceous particles collected during CARES at the time of pollution accumulation event (June 27-29, 2010), when in situ measurements indicated an increase in the organic carbon content of aerosols as the Sacramento urban plume aged. Computer controlled scanning electron microscopy coupled with an energy dispersive X-ray detector (CCSEM/EDX) and scanning transmission X-ray microscopy coupled with near edge X-ray absorption spectroscopy (STXM/NEXAFS) were used to probe the chemical composition and morphology of individual particles. It was found that the mass of organic carbon on individual particles increased through condensation of secondary organic aerosol. STXM/NEXAFS indicated that the number fraction of homogenous organic particles lacking inorganic inclusions (greater than ~50 nm diameter) increased with plume age as did the organic mass per particle. Comparison of the CARES spectro-microscopic data set with a similar dataset obtained in Mexico City during the MILAGRO campaign showed that individual particles in Mexico City contained twice as much carbon as those sampled during CARES. The number fraction of soot particles at the Mexico City urban site (30%) was larger than at the CARES urban site (10%) and the most aged samples from CARES contained less carbon-carbon double bonds. Differences between carbonaceous particles in Mexico City and California result from different sources, photochemical conditions, gas phase reactants, and secondary organic aerosol precursors. The detailed results provided by these spectro-microscopic measurements will allow for a comprehensive evaluation of aerosol process models used in climate research.

Moffet, Ryan C.; Rodel, Tobias; Kelly, Stephen T.; Yu, Xiao-Ying; Carroll, Gregory; Fast, Jerome D.; Zaveri, Rahul A.; Laskin, Alexander; Gilles, Mary K.

2013-10-29T23:59:59.000Z

240

Evaluating WRF-Chem aerosol indirect effects in Southeast Pacific marine stratocumulus during VOCALS-REx  

SciTech Connect (OSTI)

We evaluate a regional-scale simulation with the WRF-Chem model for the VAMOS (Variability of the American Monsoon Systems) Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx), which sampled the Southeast Pacific's persistent stratocumulus deck. Evaluation of VOCALS-REx ship-based and aircraft observations focuses on analyzing how aerosol loading affects marine boundary layer (MBL) dynamics and cloud microphysics. We compare local time series and campaign averaged longitudinal gradients, and highlight differences in model simulations with (W) and without wet (NW) deposition processes. The higher aerosol loadings in the NW case produce considerable changes in MBL dynamics and cloud microphysics, in accordance with the established conceptual model of aerosol indirect effects. These include increase in cloud albedo, increase in MBL and cloud heights, drizzle suppression, increase in liquid water content, and increase in cloud lifetime. Moreover, better statistical representation of aerosol mass and number concentration improves model fidelity in reproducing observed spatial and temporal variability in cloud properties, including top and base height, droplet concentration, water content, rain rate, optical depth (COD) and liquid water path (LWP). Together, these help to quantify confidence in WRF-Chem's modeled aerosol-cloud interactions, while identifying structural and parametric uncertainties including: irreversibility in rain wet removal; overestimation of marine DMS and sea salt emissions and accelerated aqueous sulfate conversion. Our findings suggest that WRF-Chem simulates marine cloud-aerosol interactions at a level sufficient for applications in forecasting weather and air quality and studying aerosol climate forcing, including the reliability required for policy analysis and geo-engineering applications.

Saide, Pablo; Spak, S. N.; Carmichael, Gregory; Mena-Carrasco, M. A.; Yang, Qing; Howell, S. G.; Leon, Dolislager; Snider, Jefferson R.; Bandy, Alan R.; Collett, Jeffrey L.; Benedict, K. B.; de Szoeke, S.; Hawkins, Lisa; Allen, Grant; Crawford, I.; Crosier, J.; Springston, S. R.

2012-03-30T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Southern hemisphere tropospheric aerosol microphysics  

SciTech Connect (OSTI)

Aerosol particle size distribution data have been obtained in the southern hemisphere from approximately 4{degree}S to 44{degree}S and between ground level and 6 km, in the vicinity of eastern Australia. The relative shape of the free-tropospheric size distribution for particles with radii larger than approximately 0.04 {mu}m was found to be remarkably stable with time, altitude, and location for the autumn-winter periods considered. This was despite some large concentration changes which were found to be typical of the southeastern Australian coastal region. The majority of free-troposphere large particles were found to have sulfuric acid or lightly ammoniated sulfate morphology. Large particles in the boundary layer almost exclusively had a sea-salt morphology.

Gras, J.L. (Commonwealth Scientific and Industrial Research Organization, Aspendale (Australia))

1991-03-20T23:59:59.000Z

242

Radiative and climate impacts of absorbing aerosols  

E-Print Network [OSTI]

incident radiation are distinguished, and albedos for oceanOceans using multiple satellite datasets in conjunction with MACR (Monte Carlo Aerosol-Cloud-Radiation)ocean temperature is coupled with the rest of the climate system, the dimming of surface radiation

Zhu, Aihua

2010-01-01T23:59:59.000Z

243

Aerosol remote sensing in polar regions  

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

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.

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

244

Aerosol fabrication methods for monodisperse nanoparticles  

DOE Patents [OSTI]

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.

Jiang, Xingmao; Brinker, C Jeffrey

2014-10-21T23:59:59.000Z

245

Development of plutonium aerosol fractionation system  

E-Print Network [OSTI]

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...

Mekala, Malla R.

1993-01-01T23:59:59.000Z

246

Photophoretic, thermophoretic, and diffusophoretic motion of heated nonvolatile aerosol particles  

SciTech Connect (OSTI)

The authors formulate (in the Stokes approximation) a theory of photophoretic, thermophoretic, and diffusophoretic motion of large and moderate-size solid aerosol particles suspended in compressible gaseous media in the case where the particle mean surface temperature is much greater than the temperature of the surrounding medium at infinity. The particle transport process is analyzed at thermal and diffusion Peclet numbers much smaller than unity. The gasdynamic equations are solved with allowance for the compressibility of the gaseous medium along with a power-law temperature dependence for the transfer coefficients. The problem is solved in spherical coordinates with origin at the center of the representative particle.

Shchukin, E.R.; Malai, N.V.

1988-10-01T23:59:59.000Z

247

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

SciTech Connect (OSTI)

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.

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

2014-08-01T23:59:59.000Z

248

Rapid Solar-thermal Dissociation of Natural Gas in an Aerosol Flow Reactor  

E-Print Network [OSTI]

/or hydrogen powered fuel cell vehicles could help to mitigate the energy supply and environmental problems black production. For solar-thermal processing, where carbon black is sold, fossil energy usageRapid Solar-thermal Dissociation of Natural Gas in an Aerosol Flow Reactor Jaimee Dahl a , Karen

249

A Numerical Sensitivity Study of Aerosol Influence on Immersion Freezing in Mixed-Phase Stratiform Clouds  

E-Print Network [OSTI]

freezing in a mixed-phase stratiform cloud. Immersion freez- ing is represented using a parameterization, and the larger droplets nucleate into ice particles through the immersion freezing process. In mixed-phaseA Numerical Sensitivity Study of Aerosol Influence on Immersion Freezing in Mixed-Phase Stratiform

Eloranta, Edwin W.

250

E-Print Network 3.0 - aerosol chemical vapor Sample Search Results  

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

chemical and microphysical properties influence aerosol optical properties and radiative effects... distribution of aerosol extensive and intensive properties will aid ......

251

Small-Scale Spray Releases: Initial Aerosol Test Results  

SciTech Connect (OSTI)

One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of anti-foam agents was assessed with most of the simulants. Orifices included round holes and rectangular slots. The round holes ranged in size from 0.2 to 4.46 mm. The slots ranged from (width × length) 0.3 × 5 to 2.74 × 76.2 mm. Most slots were oriented longitudinally along the pipe, but some were oriented circumferentially. In addition, a limited number of multi-hole test pieces were tested in an attempt to assess the impact of a more complex breach. Much of the testing was conducted at pressures of 200 and 380 psi, but some tests were conducted at 100 psi. Testing the largest postulated breaches was deemed impractical because of the large size of some of the WTP equipment. This report presents the experimental results and analyses for the aerosol measurements obtained in the small-scale test stand. It includes a description of the simulants used and their properties, equipment and operations, data analysis methodologies, and test results. The results of tests investigating the role of slurry particles in plugging small breaches are reported in Mahoney et al. (2012). The results of the aerosol measurements in the large-scale test stand are reported in Schonewill et al. (2012) along with an analysis of the combined results from both test scales.

Mahoney, Lenna A.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, Garrett N.; Kurath, Dean E.; Buchmiller, William C.; Smith, Dennese M.; Blanchard, Jeremy; Song, Chen; Daniel, Richard C.; Wells, Beric E.; Tran, Diana N.; Burns, Carolyn A.

2012-11-01T23:59:59.000Z

252

Small-Scale Spray Releases: Initial Aerosol Test Results  

SciTech Connect (OSTI)

One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and net generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of antifoam agents was assessed with most of the simulants. Orifices included round holes and rectangular slots. For the combination of both test stands, the round holes ranged in size from 0.2 to 4.46 mm. The slots ranged from (width × length) 0.3 × 5 to 2.74 × 76.2 mm. Most slots were oriented longitudinally along the pipe, but some were oriented circumferentially. In addition, a limited number of multi-hole test pieces were tested in an attempt to assess the impact of a more complex breach. Much of the testing was conducted at pressures of 200 and 380 psi, but some tests were conducted at 100 psi. Testing the largest postulated breaches was deemed impractical because of the much larger flow rates and equipment that would be required. This report presents the experimental results and analyses for the aerosol measurements obtained in the small-scale test stand. It includes a description of the simulants used and their properties, equipment and operations, data analysis methodologies, and test results. The results of tests investigating the role of slurry particles in plugging small breaches are reported in Mahoney et al. (2012). The results of the aerosol measurements in the large-scale test stand are reported in Schonewill et al. (2012) along with an analysis of the combined results from both test scales.

Mahoney, Lenna A.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, Garrett N.; Kurath, Dean E.; Buchmiller, William C.; Smith, Dennese M.; Blanchard, Jeremy; Song, Chen; Daniel, Richard C.; Wells, Beric E.; Tran, Diana N.; Burns, Carolyn A.

2013-05-29T23:59:59.000Z

253

Large-Scale Spray Releases: Initial Aerosol Test Results  

SciTech Connect (OSTI)

One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of anti-foam agents was assessed with most of the simulants. Orifices included round holes and rectangular slots. The round holes ranged in size from 0.2 to 4.46 mm. The slots ranged from (width × length) 0.3 × 5 to 2.74 × 76.2 mm. Most slots were oriented longitudinally along the pipe, but some were oriented circumferentially. In addition, a limited number of multi-hole test pieces were tested in an attempt to assess the impact of a more complex breach. Much of the testing was conducted at pressures of 200 and 380 psi, but some tests were conducted at 100 psi. Testing the largest postulated breaches was deemed impractical because of the large size of some of the WTP equipment. The purpose of this report is to present the experimental results and analyses for the aerosol measurements obtained in the large-scale test stand. The report includes a description of the simulants used and their properties, equipment and operations, data analysis methodology, and test results. The results of tests investigating the role of slurry particles in plugging of small breaches are reported in Mahoney et al. 2012a. The results of the aerosol measurements in the small-scale test stand are reported in Mahoney et al. (2012b).

Schonewill, Philip P.; Gauglitz, Phillip A.; Bontha, Jagannadha R.; Daniel, Richard C.; Kurath, Dean E.; Adkins, Harold E.; Billing, Justin M.; Burns, Carolyn A.; Davis, James M.; Enderlin, Carl W.; Fischer, Christopher M.; Jenks, Jeromy WJ; Lukins, Craig D.; MacFarlan, Paul J.; Shutthanandan, Janani I.; Smith, Dennese M.

2012-12-01T23:59:59.000Z

254

Aerosol characterization study using multi-spectrum remote sensing measurement techniques.  

SciTech Connect (OSTI)

A unique aerosol flow chamber coupled with a bistatic LIDAR system was implemented to measure the optical scattering cross sections and depolarization ratio of common atmospheric particulates. Each of seven particle types (ammonium sulfate, ammonium nitrate, sodium chloride, potassium chloride, black carbon and Arizona road dust) was aged by three anthropogenically relevant mechanisms: 1. Sulfuric acid deposition, 2. Toluene ozonolysis reactions, and 3. m-Xylene ozonolysis reactions. The results of pure particle scattering properties were compared with their aged equivalents. Results show that as most particles age under industrial plume conditions, their scattering cross sections are similar to pure black carbon, which has significant impacts to our understanding of aerosol impacts on climate. In addition, evidence emerges that suggest chloride-containing aerosols are chemically altered during the organic aging process. Here we present the direct measured scattering cross section and depolarization ratios for pure and aged atmospheric particulates.

Glen, Crystal Chanea; Sanchez, Andres L.; Lucero, Gabriel Anthony; Schmitt, Randal L.; Johnson, Mark S.; Tezak, Matthew Stephen; Servantes, Brandon Lee

2013-09-01T23:59:59.000Z

255

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

256

Chemical Composition and Sources of Coastal Marine Aerosol Particles during the 2008 VOCALS-REx Campaign  

SciTech Connect (OSTI)

The chemical composition of aerosol particles (Dp 1.5 ?m) was measured over the southeast Pacific Ocean during the VAMOS (Variability of the American Monsoon Systems) Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-Rex) between 16 October and 15 November 2008 using the US Department of Energy (DOE) G-1 aircraft. The objective of these flights was to gain an understanding of the sources and evolution of these aerosols, and of how they interact with the marine stratus cloud layer that prevails in this region of the globe. Our measurements showed that the marine boundary layer (MBL) aerosol mass was dominated by non-sea-salt SO2?4, followed by Na+, Cl?, Org (total organics), NH+4 , and NO?3 , in decreasing order of importance; CH3SO?3 (MSA), Ca2+, and K+ rarely exceeded their limits of detection. Aerosols were strongly acidic with a NH+4 to SO2?4 equivalents ratio typically < 0.3. Sea-salt aerosol (SSA) particles, represented by NaCl, exhibited Cl? deficits caused by both HNO3 and H2SO4, but for the most part were externally mixed with particles, mainly SO2?4. SSA contributed only a small fraction of the total accumulation mode particle number concentration. It was inferred that all aerosol species (except SSA) were of predominantly continental origin because of their strong land-to-sea concentration gradient. Comparison of relative changes in median values suggests that (1) an oceanic source of NH3 is present between 72° W and 76° W, (2) additional organic aerosols from biomass burns or biogenic precursors were emitted from coastal regions south of 31° S, with possible cloud processing, and (3) free tropospheric (FT) contributions to MBL gas and aerosol concentrations were negligible. The very low levels of CH3SO?3 observed as well as the correlation between SO2?4 and NO?3 (which is thought primarily anthropogenic) suggest a limited contribution of DMS to SO2?4 aerosol production during VOCALS.

Lee, Y.- N.; Springston, S.; Jayne, John T.; Wang, Jian; Hubbe, John M.; Senum, Gunnar I.; Kleinman, Lawrence I.; Daum, Peter H.

2014-05-23T23:59:59.000Z

257

Study of Mechanisms of Aerosol Indirect Effects on Glaciated Clouds: Progress during the Project Final Technical Report  

SciTech Connect (OSTI)

This 3-year project has studied how aerosol pollution influences glaciated clouds. The tool applied has been an 'aerosol-cloud model'. It is a type of Cloud-System Resolving Model (CSRM) modified to include 2-moment bulk microphysics and 7 aerosol species, as described by Phillips et al. (2009, 2013). The study has been done by, first, improving the model and then performing sensitivity studies with validated simulations of a couple of observed cases from ARM. These are namely the Tropical Warm Pool International Cloud Experiment (TWP-ICE) over the tropical west Pacific and the Cloud and Land Surface Interaction Campaign (CLASIC) over Oklahoma. During the project, sensitivity tests with the model showed that in continental clouds, extra liquid aerosols (soluble aerosol material) from pollution inhibited warm rain processes for precipitation production. This promoted homogeneous freezing of cloud droplets and aerosols. Mass and number concentrations of cloud-ice particles were boosted. The mean sizes of cloud-ice particles were reduced by the pollution. Hence, the lifetime of glaciated clouds, especially ice-only clouds, was augmented due to inhibition of sedimentation and ice-ice aggregation. Latent heat released from extra homogeneous freezing invigorated convective updrafts, and raised their maximum cloud-tops, when aerosol pollution was included. In the particular cases simulated in the project, the aerosol indirect effect of glaciated clouds was twice than of (warm) water clouds. This was because glaciated clouds are higher in the troposphere than water clouds and have the first interaction with incoming solar radiation. Ice-only clouds caused solar cooling by becoming more extensive as a result of aerosol pollution. This 'lifetime indirect effect' of ice-only clouds was due to higher numbers of homogeneously nucleated ice crystals causing a reduction in their mean size, slowing the ice-crystal process of snow production and slowing sedimentation. In addition to the known indirect effects (glaciation, riming and thermodynamic), new indirect effects were discovered and quantified due to responses of sedimentation, aggregation and coalescence in glaciated clouds to changing aerosol conditions. In summary, the change in horizontal extent of the glaciated clouds ('lifetime indirect effects'), especially of ice-only clouds, was seen to be of higher importance in regulating aerosol indirect effects than changes in cloud properties ('cloud albedo indirect effects').

None

2013-10-18T23:59:59.000Z

258

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

SciTech Connect (OSTI)

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.

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

2013-05-20T23:59:59.000Z

259

Working Paper  

E-Print Network [OSTI]

Jul 2, 2010 ... Working Paper. Branch and Bound Algorithms for ...... interest when evaluating the performance. First, each derived subproblem means usage ...

2010-07-16T23:59:59.000Z

260

Aerosol flow reactor production of superconducting ceramic powder  

SciTech Connect (OSTI)

Potential applications and basic studies of superconducting ceramics require the reproducible production of chemically homogeneous, ultrapure powders with controlled particle size distributions. Previous work has mainly examined the use of liquid and solid phase methods for superconducting powder production. In this work, it is shown that carbon-free, submicron powders based on the Y-Ba-Cu-O, La-Sr-Cu-O, Bi-Ca-Sr-Cu-O and Tl-Ca-Ba-Cu-O systems can be produced in a gaseous flow system by reacting aerosol particles containing the nitrate salts of the appropriate metals in flowing oxygen at temperatures of 900 - 1100C. It is also demonstrated that composite Cu/YBa/sub 2/Cu/sub 3/O/sub 7/ wires can be fabricated by thermophoretic deposition of the particles onto the inner surface of a Cu tube hby sintering/annealing.

Kodas, T. (New Mexico Univ., Albuquerque, NM (USA). Dept. of Nuclear Engineering); Engler, E.; Lee, V.; Parkin, L.S. (Research Div., Almaden Research Center, San Jose, CA (US))

1988-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Work Authorization System  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

It establishes a work authorization and control process for work performed by designated management and operating (M&O), management and integrating (M&I), environmental restoration management contracts (ERMC) and other contracts determined by the Procurement Executive (hereafter referred to as M&O contractors). Cancels DOE O 5700.7C. Canceled by DOE O 412.1A.

1999-04-20T23:59:59.000Z

262

Evaluating Clouds, Aerosols, and their Interactions in Three Global Climate Models using COSP and Satellite Observations  

SciTech Connect (OSTI)

Accurately representing aerosol-cloud interactions in global climate models is challenging. As parameterizations evolve, it is important to evaluate their performance with appropriate use of observations. In this work we compare aerosols, clouds, and their interactions in three climate models (AM3, CAM5, ModelE) to MODIS satellite observations. Modeled cloud properties were diagnosed using the CFMIP Observations Simulator Package (COSP). Cloud droplet number concentrations (N) were derived using the same algorithm for both satellite-simulated model values and observations. We find that aerosol optical depth tau simulated by models is similar to observations. For N, AM3 and CAM5 capture the observed spatial pattern of higher values in near-coast versus remote ocean regions, though modeled values in general are higher than observed. In contrast, ModelE simulates lower N in most near-coast versus remote regions. Aerosol- cloud interactions were computed as the sensitivity of N to tau for marine liquid clouds off the coasts of South Africa and Eastern Asia where aerosol pollution varies in time. AM3 and CAM5 are in most cases more sensitive than observations, while the sensitivity for ModelE is statistically insignificant. This widely used sensitivity could be subject to misinterpretation due to the confounding influence of meteorology on both aerosols and clouds. A simple framework for assessing the N – tau sensitivity at constant meteorology illustrates that observed sensitivity can change from positive to statistically insignificant when including the confounding influence of relative humidity. Satellite simulated values of N were compared to standard model output and found to be higher with a bias of 83 cm-3.

Ban-Weiss, George; Jin, Ling; Bauer, S.; Bennartz, Ralph; Liu, Xiaohong; Zhang, Kai; Ming, Yi; Guo, Huan; Jiang, Jonathan

2014-09-23T23:59:59.000Z

263

Aerosol beam-focus laser-induced plasma spectrometer device  

DOE Patents [OSTI]

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.

Cheng, Meng-Dawn (Oak Ridge, TN)

2002-01-01T23:59:59.000Z

264

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...

265

Process to make core-shell structured nanoparticles  

DOE Patents [OSTI]

Disclosed is a process for making a composite material that contains core-shell structured nanoparticles. The process includes providing a precursor in the form of a powder a liquid and/or a vapor of a liquid that contains a core material and a shell material, and suspending the precursor in an aerosol gas to produce an aerosol containing the precursor. In addition, the process includes providing a plasma that has a hot zone and passing the aerosol through the hot zone of the plasma. As the aerosol passes through the hot zone of the plasma, at least part of the core material and at least part of the shell material in the aerosol is vaporized. Vapor that contains the core material and the shell material that has been vaporized is removed from the hot zone of the plasma and allowed to condense into core-shell structured nanoparticles.

Luhrs, Claudia; Phillips, Jonathan; Richard, Monique N

2014-01-07T23:59:59.000Z

266

Project of Aerosol Optical Depth Change in South America  

E-Print Network [OSTI]

AerosolDepth Brazil Bolivia French Guiana Suriname Guyana Venezuela Colombia Ecuador Peru Chile Argentina Suriname Guyana Venezuela Colombia Ecuador Peru Chile Argentina Paraguay Uruguay #12;Statistics of Aerosol M ean D ec 01 to 06 Mean Month AerosolDepth Brazil Bolivia French Guiana Suriname Guyana Venezuela

Frank, Thomas D.

267

Sulfuric acid deposition from stratospheric geoengineering with sulfate aerosols  

E-Print Network [OSTI]

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

Robock, Alan

268

Organic and Inorganic Aerosol Below-Cloud Scavenging by  

E-Print Network [OSTI]

concentrations, with an average gravimetric PM1.0 of 8.2 ( 1.6 µg m-3 and an average Fourier transform infrared-rinsing behavior was unaffected by source type. The aerosol OM was hydrophilic throughout the sampling period the description of aerosol lifetimes in global models. Introduction Wet and dry deposition of aerosol particles

Russell, Lynn

269

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

SciTech Connect (OSTI)

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.

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

270

Aerodynamic Focusing Of High-Density Aerosols  

SciTech Connect (OSTI)

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.

Ruiz, D. E.; Fisch, Nathaniel

2014-02-24T23:59:59.000Z

271

Near real time vapor detection and enhancement using aerosol adsorption  

SciTech Connect (OSTI)

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.

Novick, Vincent J.; Johnson, Stanley A.

1997-12-01T23:59:59.000Z

272

Technical Note: Estimating Aerosol Effects on Cloud Radiative Forcing  

SciTech Connect (OSTI)

Estimating anthropogenic aerosol effects on the planetary energy balance through the aerosol influence on clouds using the difference in cloud radiative forcing from simulations with and without anthropogenic emissions produces estimates that are positively biased. A more representative method is suggested using the difference in cloud radiative forcing calculated with aerosol radiative effects neglected. The method also yields an aerosol radiative forcing decomposition that includes a term quantifying the impact of changes in surface albedo. The method requires only two additional diagnostic calculations: the whole-sky and clear-sky top-of-atmosphere radiative flux with aerosol radiative effects neglected.

Ghan, Steven J.

2013-10-09T23:59:59.000Z

273

Near real time vapor detection and enhancement using aerosol adsorption  

DOE Patents [OSTI]

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.

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

1999-08-03T23:59:59.000Z

274

Near real time vapor detection and enhancement using aerosol adsorption  

DOE Patents [OSTI]

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.

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

1999-01-01T23:59:59.000Z

275

Spent fuel sabotage test program, characterization of aerosol dispersal : interim final report.  

SciTech Connect (OSTI)

This multinational, multi-phase spent fuel sabotage test program is quantifying the aerosol particles produced when the products of a high energy density device (HEDD) interact with and explosively particulate test rodlets that contain pellets of either surrogate materials or actual spent fuel. This program provides source-term data that are relevant to plausible sabotage scenarios in relation to spent fuel transport and storage casks and associated risk assessments. We present details and significant results obtained from this program from 2001 through 2007. Measured aerosol results include: respirable fractions produced; amounts, nuclide content, and produced particle size distributions and morphology; measurements of volatile fission product species enhanced sorption--enrichment factors onto respirable particles; and, status on determination of the spent fuel ratio, SFR, needed for scaling studies. Emphasis is provided on recent Phase 3 tests using depleted uranium oxide pellets plus non-radioactive fission product dopants in surrogate spent fuel test rodlets, plus the latest surrogate cerium oxide results and aerosol laboratory supporting calibration work. The DUO{sub 2}, CeO{sub 2}, plus fission product dopant aerosol particle results are compared with available historical data. We also provide a status review on continuing preparations for the final Phase 4 in this program, tests using individual short rodlets containing actual spent fuel from U.S. PWR reactors, with both high- and lower-burnup fuel. The source-term data, aerosol results, and program design have been tailored to support and guide follow-on computer modeling of aerosol dispersal hazards and radiological consequence assessments. This spent fuel sabotage, aerosol test program was performed primarily at Sandia National Laboratories, with support provided by both the U.S. Department of Energy and the Nuclear Regulatory Commission. This program has significant input from, and is cooperatively supported and coordinated by both the U.S. and international program participants in Germany, France, and others, as part of the International Working Group for Sabotage Concerns of Transport and Storage Casks (WGSTSC).

Gregson, Michael Warren; Brockmann, John E.; Loiseau, Olivier (Institut de Radioprotection et de Surete Nucleaire, France); Klennert, Lindsay A.; Nolte, Oliver (Fraunhofer Institut fur Toxikologie und Experimentelle Medizin, Germany); Molecke, Martin Alan; Autrusson, Bruno A. (Institut de Radioprotection et de Surete Nucleaire, France); Koch, Wolfgang (Fraunhofer Institut fur Toxikologie und Experimentelle Medizin, Germany); Pretzsch, Gunter Guido (Gesellschaft fur Anlagen- und Reaktorsicherheit, Germany); Brucher, Wenzel (Gesellschaft fur Anlagen- und Reaktorsicherheit, Germany); Steyskal, Michele D.

2008-03-01T23:59:59.000Z

276

Two Hundred Fifty Years of Aerosols and Climate: The End of the Age of Aerosols  

SciTech Connect (OSTI)

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.

Smith, Steven J.; Bond, Tami C.

2014-01-20T23:59:59.000Z

277

Modeling LIDAR Detection of Biological Aerosols to Determine Optimum Implementation Strategy  

SciTech Connect (OSTI)

This report summarizes work performed for a larger multi-laboratory project named the Background Interferent Measurement and Standards project. While originally tasked to develop algorithms to optimize biological warfare agent detection using UV fluorescence LIDAR, the current uncertainties in the reported fluorescence profiles and cross sections the development of any meaningful models. It was decided that a better approach would be to model the wavelength-dependent elastic backscattering from a number of ambient background aerosol types, and compare this with that generated from representative sporulated and vegetative bacterial systems. Calculations in this report show that a 266, 355, 532 and 1064 nm elastic backscatter LIDAR experiment will allow an operator to immediately recognize when sulfate, VOC-based or road dust (silicate) aerosols are approaching, independent of humidity changes. It will be more difficult to distinguish soot aerosols from biological aerosols, or vegetative bacteria from sporulated bacteria. In these latter cases, the elastic scattering data will most likely have to be combined with UV fluorescence data to enable a more robust categorization.

Sheen, David M.; Aker, Pam M.

2007-09-19T23:59:59.000Z

278

Going To Work: Work Relationships  

E-Print Network [OSTI]

One of a worker's top goals should be to develop good relationships with coworkers and supervisers. This publication discusses five general rules for building good relationships at work and offers advice on handling criticism....

Hoffman, Rosemarie

2000-07-20T23:59:59.000Z

279

Aerosol chemical vapor deposition of metal oxide films  

DOE Patents [OSTI]

A process of preparing a film of a multicomponent metal oxide including: forming an aerosol from a solution comprised of a suitable solvent and at least two precursor compounds capable of volatilizing at temperatures lower than the decomposition temperature of said precursor compounds; passing said aerosol in combination with a suitable oxygen-containing carrier gas into a heated zone, said heated zone having a temperature sufficient to evaporate the solvent and volatilize said precursor compounds; and passing said volatilized precursor compounds against the surface of a substrate, said substrate having a sufficient temperature to decompose said volatilized precursor compounds whereby metal atoms contained within said volatilized precursor compounds are deposited as a metal oxide film upon the substrate is disclosed. In addition, a coated article comprising a multicomponent metal oxide film conforming to the surface of a substrate selected from the group consisting of silicon, magnesium oxide, yttrium-stabilized zirconium oxide, sapphire, or lanthanum gallate, said multicomponent metal oxide film characterized as having a substantially uniform thickness upon said substrate.

Ott, K.C.; Kodas, T.T.

1994-01-11T23:59:59.000Z

280

Amine-Amine Exchange in Aminium-Methanesulfonate Aerosols  

SciTech Connect (OSTI)

Aerosol particles are ubiquitous in the atmosphere and have been shown to impact the Earth’s climate, reduce visibility, and adversely affect human health. Modeling the evolution of aerosol systems requires an understanding of the species and mechanisms involved in particle growth, including the complex interactions between particle- and gas-phase species. Here we report studies of displacement of amines (methylamine, dimethylamine or trimethylamine) in methanesulfonate salt particles by exposure to a different gas-phase amine, using a single particle mass spectrometer, SPLAT II. The variation of the displacement with the nature of the amine suggests that behavior is dependent on water in or on the particles. Small clusters of methanesulfonic acid with amines are used as a model in quantum chemical calculations to identify key structural elements that are expected to influence water uptake, and hence the efficiency of displacement by gas-phase molecules in the aminium salts. Such molecular-level understanding of the processes affecting the ability of gas-phase amines to displace particle-phase aminium species is important for modeling the growth of particles and their impacts in the atmosphere.

Dawson, Matthew L.; Varner, Mychel E.; Perraud, Veronique M.; Ezell, Michael J.; Wilson, Jacqueline M.; Zelenyuk, Alla; Gerber, Robert B.; Finlayson-Pitts, Barbara J.

2014-12-18T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

E-Print Network 3.0 - aqueous sol-gel process Sample Search Results  

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

Process control 12 2.4 Aerosol method 18 2... synthesis 27 A.3 Sol-gel process 27 A.4 Aerogel method 27 A.5 Pechini and Citrate gel method 27 A.6 Low... process The sol-gel ......

282

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

E-Print Network [OSTI]

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

Weber, Rodney

283

Work Plan  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched FerromagnetismWaste and MaterialsWenjun1 Table 1.14 Sales of4) MonthlyWork &Work

284

Working Copy  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered energy consumption byAbout PrintableBlenderWhatFellowsWood and4213WorkWork

285

Cyclone aerosol sampling and particle deposition in tubing elements following elbow bends  

E-Print Network [OSTI]

on Deposition. Influence of an Elbow Bend on Straight Tube Deposition. . . Discussion of Errors. . . . . . . . . . . . . . 27 3l 35 SUMMARY AND CONCLUSIONS. 36 Ambient Air Sampling Aerosol Transport . 36 37 FUTI JRE WORK 38 Ambient Air Sampling... Cunningham's correction factor for a particle reference particle concentration concetration of the sodium fluoroscein collected at the inlet to the system cutpoint diameter aerodynamic equivalent diameter cyclone body diameter cyclone outlet tube...

Wente, William Baker

1995-01-01T23:59:59.000Z

286

Calibration of the On-Line Aerosol Monitor (OLAM) with ammonium chloride and sodium chloride aerosols  

SciTech Connect (OSTI)

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.

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

287

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]

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 ...

Hohaus, T.

288

Remedial action plan for the inactive Uranium Processing Site at Naturita, Colorado. Remedial action plan: Attachment 2, Geology report, Attachment 3, Ground water hydrology report: Working draft  

SciTech Connect (OSTI)

The uranium processing site near Naturita, Colorado, is one of 24 inactive uranium mill sites designated to be cleaned up by the US Department of Energy (DOE) under the Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA), 42 USC {section}7901 et seq. Part of the UMTRCA requires that the US Nuclear Regulatory Commission (NRC) concur with the DOE`s remedial action plan (RAP) and certify that the remedial action conducted at the site complies with the standards promulgated by the US Environmental Protection Agency (EPA). This RAP serves two purposes. First, it describes the activities that are proposed by the DOE to accomplish remediation and long-term stabilization and control of the radioactive materials at the inactive uranium processing site near Naturita, Colorado. Second, this RAP, upon concurrence and execution by the DOE, the state of Colorado, and the NRC, become Appendix B of the cooperative agreement between the DOE and the state of Colorado.

Not Available

1994-09-01T23:59:59.000Z

289

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

290

Aerosol Spray Synthesis of Porous Molybdenum Sulfide  

E-Print Network [OSTI]

, and colloidal silica, SiO2, was ultrasonically nebulized using a household humidifier; the resulting aerosol in materials science because of their ability to be scaled-up for industrial applications.[2] USP solution, as indicated by Eq. 2. Typically, micron-sized particles are obtained; however, by adding

Suslick, Kenneth S.

291

3, 59195976, 2003 The nitrate aerosol  

E-Print Network [OSTI]

ACPD 3, 5919­5976, 2003 The nitrate aerosol field over Europe M. Schaap et al. Title Page Abstract of Utrecht, Institute of Marine and Atmospheric Science, PO Box 80005, 3508 TA, Utrecht, The Netherlands 2, The Netherlands 3 Netherlands Energy Research Foundation (ECN), PO Box 1, 1755 LE Petten, The Netherlands 4 Joint

Paris-Sud XI, Université de

292

Source Apportionment of Carbonaceous Aerosols using  

E-Print Network [OSTI]

are different than the collection of particles from water Filtration has high efficiency for all sizes Size Condensation Nuclei (CCN) Human health Carbonaceous aerosol implicated as important for toxicity and adverse of particulate matter Again, agreement between these two approaches would give a high level of confidence

Einat, Aharonov

293

Transportation External Coordination Working Group:  

Broader source: Energy.gov (indexed) [DOE]

External Coordination Working Group: Background and Process Judith Holm National Transportation Program Albuquerque, New Mexico April 21, 2004 TEC History * DOE's Office of...

294

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

SciTech Connect (OSTI)

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.

Marlow, W.H.

1994-12-31T23:59:59.000Z

295

Fermilab at Work | Work Resources  

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

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296

Direct and semidirect aerosol effects of Southern African biomass burning aerosol  

SciTech Connect (OSTI)

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.

Sakaeda, Naoko; Wood, Robert; Rasch, Philip J.

2011-06-21T23:59:59.000Z

297

EVALUATION OF AEROSOL EMISSIONS DOWNSTREAM OF AN AMMONIA-BASED SO2 SCRUBBER  

SciTech Connect (OSTI)

Depending on the size and type of boiler, the 1990 Clean Air Act Amendments required specific reductions in SO{sub 2} emissions from coal-fired electric utilities. To meet these requirements, SO{sub 2} reduction strategies have included installing scrubbing technology, switching to a more expensive low-sulfur coal, or purchasing SO{sub 2} allowances. It is expected that over the next 10 years there will be an increase in the price of low-sulfur coals, but that higher-sulfur coal costs will remain the same. Technologies must be strongly considered that allow the use of high-sulfur fuels while at the same time meeting current and future SO{sub 2} emission limits. One such technology is the ammonia based flue gas desulfurization (FGD) (NH{sub 3}-based FGD) system manufactured by Marsulex Environmental Technologies (MET). The MET scrubber is a patented NH{sub 3}-based FGD process that efficiently converts SO{sub 2} (>95%) into a fertilizer product, ammonium sulfate ([NH{sub 4}]{sub 2}SO{sub 4}). A point of concern for the MET technology, as well as other FGD systems, is the emission of sulfuric acid/SO{sub 3} aerosols that could result in increased opacity at the stack. This is a direct result of firing high-sulfur fuels that naturally generate more SO{sub 3} than do low-sulfur coals. SO{sub 3} is formed during the coal combustion process. SO{sub 3} is converted to gaseous H{sub 2}SO{sub 4} by homogeneous condensation, leading to a submicron acid fume that is very difficult to capture in a dry electrostatic precipitator (ESP). The condensed acid can also combine with the fly ash in the duct and scale the duct wall, potentially resulting in corrosion of both metallic and nonmetallic surfaces. Therefore, SO{sub 3} in flue gas can have a significant impact on the performance of coal-fired utility boilers, air heaters, and ESPs. In addition to corrosion problems, excess SO{sub 3} emissions can result in plume opacity problems. Thus the Energy & Environmental Research Center (EERC) was contracted by MET and the U.S. Department of Energy (DOE) to evaluate the potential of a wet ESP for reducing SO{sub 3} emissions. The work consisted of pilot-scale tests using the EERC's slagging furnace system (SFS) to determine the effectiveness of a wet ESP to control SO{sub 3}/H{sub 2}SO{sub 4} aerosol emissions in conjunction with a dry ESP and MET's NH{sub 3}-based FGD. Because these compounds are in the form of fine particles, it is speculated that a relatively small, highly efficient wet ESP following the MET scrubber would remove these fine aerosol particles. The performance target for the wet ESP was a particulate mass collection efficiency of >90%; this level of performance would likely ensure a stack opacity of <10%.

Dennis L. Laudal

2002-04-01T23:59:59.000Z

298

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

SciTech Connect (OSTI)

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.

Novick, V.J.

1989-01-01T23:59:59.000Z

299

atmospheric aerosol processes: Topics by E-print Network  

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

Size Distribution Physics (arXiv) Summary: Atmospheric flows exhibit selfsimilar fractal spacetime fluctuations manifested as the fractal geometry to global cloud cover...

300

Atmospheric processing of organic aerosols G. Barney Ellison  

E-Print Network [OSTI]

of an aqueous core that is encapsulated in an inert, hydrophobic organic monolayer. The organic materials important roles in climate and elsewhere through their interaction with solar and terrestrial radiation

Ellison, Barney

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301

Photolytic processing of secondary organic aerosols dissolved in cloud  

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

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302

ARM - Field Campaign - 2007 Cumulus Humilis Aerosol Process Study (CHAPS)  

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

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303

Simultaneous Retrieval of Effective Refractive Index and Density from Size Distribution and Light Scattering Data: Weakly-Absorbing Aerosol  

SciTech Connect (OSTI)

We propose here a novel approach for retrieving in parallel the effective density and real refractive index of weakly absorbing aerosol from optical and size distribution measurements. Here we define “weakly absorbing” as aerosol single-scattering albedos that exceed 0.95 at 0.5 um.The required optical measurements are the scattering coefficient and the hemispheric backscatter fraction, obtained in this work from an integrating nephelometer. The required size spectra come from a Scanning Mobility Particle Sizer and an Aerodynamic Particle Sizer. The performance of this approach is first evaluated using a sensitivity study with synthetically generated but measurement-related inputs. The sensitivity study reveals that the proposed approach is robust to random noise; additionally the uncertainties of the retrieval are almost linearly proportional to the measurement errors, and these uncertainties are smaller for the real refractive index than for the effective density. Next, actual measurements are used to evaluate our approach. These measurements include the optical, microphysical, and chemical properties of weakly absorbing aerosol which are representative of a variety of coastal summertime conditions observed during the Two-Column Aerosol Project (TCAP; http://campaign.arm.gov/tcap/). The evaluation includes calculating the root mean square error (RMSE) between the aerosol characteristics retrieved by our approach, and the same quantities calculated using the conventional volume mixing rule for chemical constituents. For dry conditions (defined in this work as relative humidity less than 55%) and sub-micron particles, a very good (RMSE~3%) and reasonable (RMSE~28%) agreement is obtained for the retrieved real refractive index (1.49±0.02) and effective density (1.68±0.21), respectively. Our approach permits discrimination between the retrieved aerosol characteristics of sub-micron and sub-10micron particles. The evaluation results also reveal that the retrieved density and refractive index tend to decrease with an increase of the relative humidity.

Kassianov, Evgueni I.; Barnard, James C.; Pekour, Mikhail S.; Berg, Larry K.; Shilling, John E.; Flynn, Connor J.; Mei, Fan; Jefferson, Anne

2014-10-01T23:59:59.000Z

304

Review: engineering particles using the aerosol-through-plasma method  

SciTech Connect (OSTI)

For decades, plasma processing of materials on the nanoscale has been an underlying enabling technology for many 'planar' technologies, particularly virtually every aspect of modern electronics from integrated-circuit fabrication with nanoscale elements to the newest generation of photovoltaics. However, it is only recent developments that suggest that plasma processing can be used to make 'particulate' structures of value in fields, including catalysis, drug delivery, imaging, higher energy density batteries, and other forms of energy storage. In this paper, the development of the science and technology of one class of plasma production of particulates, namely, aerosol-through-plasma (A-T-P), is reviewed. Various plasma systems, particularly RF and microwave, have been used to create nanoparticles of metals and ceramics, as well as supported metal catalysts. Gradually, the complexity of the nanoparticles, and concomitantly their potential value, has increased. First, unique two-layer particles were generated. These were postprocessed to create unique three-layer nanoscale particles. Also, the technique has been successfully employed to make other high-value materials, including carbon nanotubes, unsupported graphene, and spherical boron nitride. Some interesting plasma science has also emerged from efforts to characterize and map aerosol-containing plasmas. For example, it is clear that even a very low concentration of particles dramatically changes plasma characteristics. Some have also argued that the local-thermodynamic-equilibrium approach is inappropriate to these systems. Instead, it has been suggested that charged- and neutral-species models must be independently developed and allowed to 'interact' only in generation terms.

Phillips, Jonathan [Los Alamos National Laboratory; Luhrs, Claudia C [UNM; Richard, Monique [TEMA

2009-01-01T23:59:59.000Z

305

Indirect radiative forcing by ion-mediated nucleation of aerosol  

SciTech Connect (OSTI)

A clear understanding of particle formation mechanisms is critical for assessing aerosol indirect radiative forcing and associated climate feedback processes. Recent studies reveal the importance of ion-mediated nucleation (IMN) in generating new particles and cloud condensation nuclei (CCN) in the atmosphere. Here we implement for the first time a physically based treatment of IMN into the Community Atmosphere Model version 5. Our simulations show that, compared to globally averaged results based on binary homogeneous nucleation (BHN), the presence of ionization (i.e., IMN) halves H2SO4 column burden, but increases the column integrated nucleation rate by around one order of magnitude, total particle number burden by a factor of ~ 3, CCN burden by ~ 10% (at 0.2% supersaturation) to 65% (at 1.0% supersaturation), and cloud droplet number burden by ~ 18%. Compared to BHN, IMN increases cloud liquid water path by 7.5%, decreases precipitation by 1.1%, and increases total cloud cover by 1.9%. This leads to an increase of total shortwave cloud radiative forcing by 3.67 W/m2 (more negative) and longwave cloud forcing by 1.78 W/m2 (more positive), resulting in a -1.9 W/m2 net change in cloud radiative forcing associated with IMN. The significant impacts of ionization on global aerosol formation, CCN abundance, and cloud radiative forcing may provide an important physical mechanism linking the global energy balance to various processes affecting atmospheric ionization, which should be properly represented in climate models.

Yu, Fangqun; Luo, Gan; Liu, Xiaohong; Easter, Richard C.; Ma, Xiaoyan; Ghan, Steven J.

2012-12-03T23:59:59.000Z

306

EVOLUTION OF TRACE GASES AND AEROSOLS IN THE MEXICO CITY POLLUTION OUTFLOW DURING A LONG RANGE TRANSPORT EVENT  

E-Print Network [OSTI]

EVOLUTION OF TRACE GASES AND AEROSOLS IN THE MEXICO CITY POLLUTION OUTFLOW DURING A LONG RANGE, NY www.bnl.gov ABSTRACT Significant chemical and physical processing of the Mexico City (MC) pollutants is expected to occur as they are advected downwind over a period of several hours to days

307

Atmospheric Chemistry, Carbon Cycle, and Climate (AC4): Observational Constraints on Sources and Sinks of Aerosols and Greenhouse Gases  

E-Print Network [OSTI]

and gas extraction can also inform future energy choices. In FY 2014, Atmospheric Chemistry, Carbon Cycle anthropogenic-biogenic emission intense regions 3. Deposition processes controlling atmospheric concentrations of aerosols and greenhouse gases Projects that quantify sources and sinks via new measurements and/or modeling

308

Climate Engineering with Stratospheric Aerosols and Associated Engineering Parameters  

SciTech Connect (OSTI)

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.

Kravitz, Benjamin S.

2013-02-12T23:59:59.000Z

309

Total aerosol effect: forcing or radiative flux perturbation?  

SciTech Connect (OSTI)

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.

Lohmann, Ulrike; Storelvmo, Trude; Jones, Andy; Rotstayn, Leon; Menon, Surabi; Quaas, Johannes; Ekman, Annica; Koch, Dorothy; Ruedy, Reto

2009-09-25T23:59:59.000Z

310

Retrieval of ozone and nitrogen dioxide concentrations from Stratospheric Aerosol and Gas Experiment III (SAGE III)  

E-Print Network [OSTI]

Retrieval of ozone and nitrogen dioxide concentrations from Stratospheric Aerosol and Gas extinction. We retrieve ozone and nitrogen dioxide number densities and aerosol extinction from transmission), Retrieval of ozone and nitrogen dioxide concentrations from Stratospheric Aerosol and Gas Experiment III

311

Correction to "Sulfuric acid deposition from stratospheric geoengineering with sulfate aerosols"  

E-Print Network [OSTI]

Correction to "Sulfuric acid deposition from stratospheric geoengineering with sulfate aerosols (2010), Correction to "Sulfuric acid deposition from stratospheric geoengineering with sulfate aerosols from stratospheric geoengineering with sulfate aerosols" (Journal of Geophysical Research, 114, D14109

Robock, Alan

312

Statistical analysis of aerosol species, trace gasses, and meteorology in Chicago  

E-Print Network [OSTI]

possible pollutant sources. Keywords Atmospheric aerosols . Canonical correlation analysis . Chicago air pollution studies involve collection and anal- ysis of atmospheric aerosols and concurrent meteorol- ogy) and principal component analysis (PCA) were applied to atmospheric aerosol and trace gas concentrations

O'Brien, Timothy E.

313

Aerosol Retrievals from ARM SGP MFRSR Data  

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

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.

Alexandrov, Mikhail

314

Stackable differential mobility analyzer for aerosol measurement  

DOE Patents [OSTI]

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.

Cheng, Meng-Dawn (Oak Ridge, TN); Chen, Da-Ren (Creve Coeur, MO)

2007-05-08T23:59:59.000Z

315

Aerosol dispersion and coagulation from a coal-fired power plant: a three dimensional numerical model  

SciTech Connect (OSTI)

A computational model to simulate the dispersion and coagulation of aerosols emitted from coal-fired power plants was constructed. In modeling the dispersion of the aerosol, turbulent diffusion and wind-driven advection are treated by a finite-difference method. Molecular coagulation is incorporated in the model to follow shifts in the particle-size distribution. Particulate coagulation is mathematically described by Timiskii's equation. The relevent semi-empirical work of Smirnov is incorporated in the model to provide for the coagultion constant. Input for the model is a bimodal, particle-size distribution measured at an operating coal-fired power plant. Simulations indicate that dispersion competes against coagulation mechanisms to maintain the bimodal shaped distribution for 32 km. Turbulence and particle settling tend to enchance coagulation effects. The size-dependent spatial segregation of particles within the plume is predicted.

Buckholtz, H.T.; Biermann, A.H.

1980-01-01T23:59:59.000Z

316

ARM - PI Product - Niamey Aerosol Optical Depths  

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

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317

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,...

318

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...

319

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...

320

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...

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

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...

322

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...

323

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:...

324

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...

325

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...

326

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...

327

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 &...

328

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...

329

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...

330

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-...

331

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...

332

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...

333

Aerosol generation and entrainment model for cough simulations.  

E-Print Network [OSTI]

??The airborne transmission of diseases is of great concern to the public health community. The possible spread of infectious disease by aerosols is of particular… (more)

Ersahin, Cem.

2007-01-01T23:59:59.000Z

334

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....

335

Resuspension studies at Bikini Atoll. [Pulmonary exposure from dust-borne plutonium aerosols  

SciTech Connect (OSTI)

The following experiments were conducted on Bikini Atoll to provide key parameters for an assessment of inhalation exposure from plutonium-contaminated dust aerosols: (1) a characterization of background (plutonium activity, dust, plutonium, sea spray, and organic aerosol concentrations); (2) a study of plutonium resuspension from a bare field; (3) a study of plutonium resuspension by traffic; and (4) a study of personal inhalation exposure. Dust concentrations of 21 ..mu..g m/sup -3/ and sea spray of 34 ..mu..g m/sup -3/ were the background throughout the Bikini Island except within 50 m of the windward beach. Background concentrations of /sup 239 +240/Pu were 60 aCi m/sup -3/ in the coconut grove and 264 aCi m/sup -3/ over rain-stabilized bare soil. The ratio of plutonium activity in aerosols relative to the activity in underlying soil, defined as the enhancement factor, EF, was typically less than one. Enhancement factors increased about 3.8 as a result of tilling. Plutonium resuspension flux was estimated at 0.49 pCi m/sup -2/ year/sup -1/ over most of Bikini Island. Aerosol size distributions associated with mass and with plutonium activity were typically log-normal with median aerodynamic diameter 2.44 ..mu..m, which decreased to 2.0 ..mu..m above freshly tilled soil. The Pu concentration in aerosols collected over disturbed soil increased by a factor of 19.1. Vehicular traffic produced dust pulses typically of 10 s duration, 28 ..mu..g m/sup -3/ average concentration, and plutonium enhancement factor 2.5. Personal dosimetry showed that enhancement of dust by a worker was a factor of 2.64 for heavy work outdoors and 1.86 for light work in and around houses. Pulmonary deposition of plutonium was calculated for various exposure conditions. The pulmonary deposition ranged from 1476 aCi h/sup -1/ to 12 aCi h/sup -1/ with intermediate values for heavy outdoor work and for light work in and around houses.

Shinn, J.H.; Homan, D.N.; Robison, W.L.

1980-02-01T23:59:59.000Z

336

E-Print Network 3.0 - administrado como aerosol Sample Search...  

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

del ozono estratosfrico, los aerosoles atmosfricos y... a los cambios en las emisiones que los GEI de larga duracin, como el CO2. Los aerosoles antropgenos... ms...

337

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...

338

E-Print Network 3.0 - aerosol condensation model Sample Search...  

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

Applied Science Collection: Environmental Sciences and Ecology 8 DETERMINING AEROSOL RADIATIVE FORCING AT ARM SITES Summary: OF AEROSOL DIRECT FORCING By linear model and by...

339

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...

340

E-Print Network 3.0 - aerosolized polymerized type Sample Search...  

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

spheric aerosol particles and isolated from fog... in atmospheric aerosol particles and rainwater in the 1980's (Si- moneit, 1980; Likens and ... Source: Ecole Polytechnique,...

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

E-Print Network 3.0 - aerosol radiative forcing Sample Search...  

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

No. DE- Summary: : WHY MEASUREMENTS ALONE CANNOT QUANTIFY AEROSOL RADIATIVE FORCING OF CLIMATE CHANGE Stephen E. Schwartz... of radiative forcing of climate change by aerosols,...

342

E-Print Network 3.0 - aerosols nanometriques application Sample...  

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

is studying how aerosol particles affect everything from Summary: of aerosol particles on climate change, public health, and renewable energy applications. In particular, he......

343

E-Print Network 3.0 - aerosol main physical Sample Search Results  

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

AND INTEGRAL AEROSOL PROPERTIES RETRIEVAL FROM RAMAN LIDAR DATA USING PRINCIPLE COMPONENT ANALYSIS Summary: retrievals of physical aerosol parameters from ground-based and...

344

Aerosol-Cloud-Precipitation Interactions in the Trade Wind Boundary Layer.  

E-Print Network [OSTI]

??This dissertation includes an overview of aerosol, cloud, and precipitation properties associated with shallow marine cumulus clouds observed during the Barbados Aerosol Cloud Experiment (BACEX,… (more)

Jung, Eunsil

2012-01-01T23:59:59.000Z

345

E-Print Network 3.0 - aerosol light absorption Sample Search...  

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

AND Summary: population centers were used to calculate the aerosol forcing due to light scattering and absorption. Directly... , NY www.bnl.gov ABSTRACT Aerosols influence...

346

Large Aerosols Play Unexpected Role in Ganges Valley | U.S. DOE...  

Office of Science (SC) Website

The data have revealed that large aerosols in this region absorb a greater amount of light than expected. The Science Aerosol particles in the atmosphere may absorb solar...

347

E-Print Network 3.0 - aerosol atmospheric interactions Sample...  

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

for Climate Summary: order estimates of aerosol-climate interaction But... only Earth System Models can include all... of the interactions (in theory at least) 12;Aerosols <>...

348

E-Print Network 3.0 - atmospheric aerosol size Sample Search...  

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

for about ten percent of all aerosols in the atmosphere. We... , can actually absorb solar energy and warm the atmosphere. Atmospheric aerosols are very important... by...

349

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;...

350

E-Print Network 3.0 - aerosol particle size Sample Search Results  

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

Summary: of aerosol over many orders-of-magnitude of particle size range, from subcritical clusters on the molecular... to modeling aerosol dynamics under conditions of new...

351

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...

352

E-Print Network 3.0 - analysis od aerosol Sample Search Results  

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

Tivanski, Rebecca Hopkins, Yury Desyaterik... of Aerosols 12;Aerosol Transport From Mexico City During MILAGRO T0 T1 T2 Mexico ... Source: Brookhaven National Laboratory,...

353

Atmospheric multiple scattering of fluorescence light from extensive air showers and effect of the aerosol size on the reconstruction of energy and depth of maximum  

E-Print Network [OSTI]

The reconstruction of the energy and the depth of maximum $X_{\\rm max}$ of an extensive air shower depends on the multiple scattering of fluorescence photons in the atmosphere. In this work, we explain how atmospheric aerosols, and especially their size, scatter the fluorescence photons during their propagation. Using a Monte Carlo simulation for the scattering of light, the dependence on the aerosol conditions of the multiple scattered light contribution to the recorded signal is fully parameterised. A clear dependence on the aerosol size is proposed for the first time. Finally, using this new parameterisation, the effect of atmospheric aerosols on the energy and on the $X_{\\rm max}$ reconstructions is presented for a vertical extensive air shower observed by a ground-based detector at $30~$km: for typical aerosol conditions, multiple scattering leads to a systematic over-estimation of $5\\pm1.5\\%$ for the energy and $4.0\\pm 1.5~$g/cm$^2$ for the $X_{\\rm max}$, where the uncertainties refer to a variation of the aerosol size.

K. Louedec; J. Colombi

2014-03-17T23:59:59.000Z

354

Aerosol radiative forcing and the accuracy of satellite aerosol optical depth retrieval  

E-Print Network [OSTI]

) of the AVHRR (Advanced Very High Resolution Radiometer) is typically between 0.06 and 0.15, while the RMSE between t = 0.1 and t = 0.8. The Department of Energy research satellite instrument, the Multispectral aerosol radiative forcing are known, the predictions of future global warming may remain unacceptably high

355

Variability of Aerosol Optical Properties from Long-term  

E-Print Network [OSTI]

%) controlled measurements: sp ­ Aerosol total light scattering coefficient at 450, 550, and 700 nm wavelengths automated generation and review of quality control plots · Weekly editing of data by station scientist]. Indirect Forcing Direct Forcing Carbon Dioxide Forcing Total Forcing Importance of Aerosols #12;Direct

Delene, David J.

356

Sulfate Aerosol Geoengineering: The Question of Justice Toby Svoboda1,*  

E-Print Network [OSTI]

Sulfate Aerosol Geoengineering: The Question of Justice Toby Svoboda1,* , Klaus Keller2 , Marlos of geoengineering as a means to address global climate change. This paper focuses on the question of whether a particular form of geoengineering, namely deploying sulfate aerosols in the stratosphere to counteract some

357

An overview of geoengineering of climate using stratospheric sulphate aerosols  

E-Print Network [OSTI]

REVIEW An overview of geoengineering of climate using stratospheric sulphate aerosols BY PHILIP J, MD 21218, USA We provide an overview of geoengineering by stratospheric sulphate aerosols. The state after geoengineering, with some regions experiencing significant changes in temperature or precipitation

Robock, Alan

358

aerosol ratio test: Topics by E-print Network  

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

aerosol ratio test 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 Effect of mineral dust aerosol...

359

Organic Aerosol Formation Downwind from the Deepwater Horizon Oil Spill  

E-Print Network [OSTI]

Organic Aerosol Formation Downwind from the Deepwater Horizon Oil Spill Nicole ONeill - ATOC 3500 and aerosol composition of air over the Deepwater Horizon oil spill in the Gulf of Mexico. · The lightest chemicals in the oil evaporated within hours, as scientists expected them to do. What they didn't expect

Toohey, Darin W.

360

Spatial and Seasonal Trends in Biogenic Secondary Organic Aerosol  

E-Print Network [OSTI]

Spatial and Seasonal Trends in Biogenic Secondary Organic Aerosol Tracers and Water-Soluble Organic biogenic secondary organic aerosol (SOA) tracers via gas chromatography-mass spectrometry (GC natural and anthropogenic sources and is dominated by terrestrial plant foliage (7). The global

Zheng, Mei

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

CLOUD PHYSICS From aerosol-limited to invigoration  

E-Print Network [OSTI]

CLOUD PHYSICS From aerosol-limited to invigoration of warm convective clouds Ilan Koren,1 * Guy Dagan,1 Orit Altaratz1 Among all cloud-aerosol interactions, the invigoration effect is the most elusive. Most of the studies that do suggest this effect link it to deep convective clouds with a warm base

Napp, Nils

362

Deposition of Biological Aerosols on HVAC Heat Exchangers  

E-Print Network [OSTI]

LBNL-47669 Deposition of Biological Aerosols on HVAC Heat Exchangers Jeffrey Siegel and Iain Walker of Biological Aerosols on HVAC Heat Exchangers Jeffrey A. Siegel Iain S. Walker, Ph.D. ASHRAE Student Member that are found in commercial and residential HVAC systems of 1 - 6 m/s (200 - 1200 ft/min), particle diameters

363

Climatology of aerosol optical depth in northcentral Oklahoma: 19922008  

E-Print Network [OSTI]

of aerosol models; for identification of aerosols from spe- cific events (e.g., the Central American fires Radiation Measurement Program central facility near Lamont, Oklahoma, since the fall of 1992. Most dimming; that is, the decrease in solar radiation reaching Earth's surface. Additionally, the wavelength

364

Absorption cross-section 139 Accumulation mode, of aerosol 146  

E-Print Network [OSTI]

133, 151 residence times 153 size distributions 144 Air composition 2 molecular weight 4, 6 Albedo 122 dioxide Coagulation (aerosol) 146 Column model 32 Conditional unstability 56 Continuity equation 75261 INDEX A Absorption cross-section 139 Accumulation mode, of aerosol 146 Acetaldehyde (CH3CHO

Jacob, Daniel J.

365

Laboratory Measurements of Sea Salt Aerosol Refractive Index  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . . . . 6 1.2.3 Complex Refractive Index . . . . . . . . . . . . . . . . . . . . 6 1.2.4 Size Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 1.3.5 Coagulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 1.4 Sea Salt AerosolsLaboratory Measurements of Sea Salt Aerosol Refractive Index Thesis submitted for the degree

Oxford, University of

366

Cloud Condensation Nuclei (CCN) Analysis of Biogenic Secondary Organic Aerosol  

E-Print Network [OSTI]

Cloud Condensation Nuclei (CCN) Analysis of Biogenic Secondary Organic Aerosol Rachel L. Atlas1' gas-phase emissions and the aerosols they form (figure 6), including a cloud condensation nuclei Cloud condensation nuclei (CCN) are particles which water vapor condenses onto to form cloud droplets

Collins, Gary S.

367

The influence of salt aerosol on alpha radiation detection by WIPP continuous air monitors  

SciTech Connect (OSTI)

Alpha continuous air monitors (CAMs) will be used at the Waste Isolation Pilot Plant (WIPP) to measure airborne transuranic radioactivity that might be present in air exhaust or in work-place areas. WIPP CAMs are important to health and safety because they are used to alert workers to airborne radioactivity, to actuate air-effluent filtration systems, and to detect airborne radioactivity so that the radioactivity can be confined in a limited area. In 1993, the Environmental Evaluation Group (EEG) reported that CAM operational performance was affected by salt aerosol, and subsequently, the WIPP CAM design and usage were modified. In this report, operational data and current theories on aerosol collection were reviewed to determine CAM quantitative performance limitations. Since 1993, the overall CAM performance appears to have improved, but anomalous alpha spectra are present when sampling-filter salt deposits are at normal to high levels. This report shows that sampling-filter salt deposits directly affect radon-thoron daughter alpha spectra and overall monitor efficiency. Previously it was assumed that aerosol was mechanically collected on the surface of CAM sampling filters, but this review suggests that electrostatic and other particle collection mechanisms are more important than previously thought. The mechanism of sampling-filter particle collection is critical to measurement of acute releases of radioactivity. 41 refs.

Bartlett, W.T.; Walker, B.A.

1996-01-01T23:59:59.000Z

368

Method of dispersing particulate aerosol tracer  

DOE Patents [OSTI]

A particulate aerosol tracer which comprises a particulate carrier of sheet silicate composition having a particle size up to one micron, and a cationic dopant chemically absorbed in solid solution in the carrier. The carrier is preferably selected from the group consisting of natural mineral clays such as bentonite, and the dopant is selected from the group consisting of rare earth elements and transition elements. The tracers are dispersed by forming an aqueous salt solution with the dopant present as cations, dispersing the carriers in the solution, and then atomizing the solution under heat sufficient to superheat the solution droplets at a level sufficient to prevent reagglomeration of the carrier particles.

O'Holleran, Thomas P. (Belleville, MI)

1988-01-01T23:59:59.000Z

369

Study of Aerosol Indirect Effects in China  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security AdministrationcontrollerNanocrystalline Gallium Oxide Thin Films.AdministrationAerosol Indirect

370

Aerosol Remote Sealing System - Energy Innovation Portal  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout the BuildingInnovation 2011 Simulation StudiesAerosol Remote Sealing

371

Light Absorption by Secondary Organic Aerosol from ?-Pinene: Effects of Oxidants, Seed Aerosol Acidity, and Relative Humidity  

SciTech Connect (OSTI)

It is well known that light absorption from dust and black carbon aerosols has a warming effect on climate while light scattering from sulfate, nitrate, and sea salt aerosols has a cooling effect. However, there are large uncertainties associated with light absorption and scattering by different types of organic aerosols, especially in the near-UV and UV spectral regions. In this paper, we present the results from a systematic laboratory study focused on measuring light absorption by secondary organic aerosols (SOA) generated from ozonolysis or NO3 oxidation of ?-pinene in the presence of neutral and acidic sulfate seed aerosols. Light absorption was monitored using photoacoustic spectrometers at four different wavelengths: 355, 405, 532 and 870 nm. Light absorption at 355 and 405 nm was observed by SOA generated from oxidation of ?-pinene in the presence of acidic sulfate seed aerosols, under dry conditions. No absorption was observed when the relative humidity was elevated to greater than 27%, or in the presence of neutral sulfate seed aerosols. The light-absorbing compounds are speculated to be aldol condensation oligomers with organosulfate and organic nitrate groups. The results of this study also indicate that organic nitrates from ?-pinene SOA formed in the presence of neutral sulfate seed aerosols do not appear to absorb near-UV and UV radiation.

Song, Chen; Gyawali, Madhu S.; Zaveri, Rahul A.; Shilling, John E.; Arnott, W. Patrick

2013-10-25T23:59:59.000Z

372

ARM: 10-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm  

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

10-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

Newsom, Rob; Goldsmith, John

373

ARM: 2-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm  

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

2-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

Sivaraman, Chitra; Flynn, Connor

374

ARM: 10-second Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm  

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

10-second Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

Sivaraman, Chitra; Flynn, Connor

375

ARM: 1-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm  

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

1-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

Sivaraman, Chitra; Flynn, Connor

376

spectra from size-resolved particle samples col-lected from the Southeastern Aerosol Visibility  

E-Print Network [OSTI]

and acrolein aerosols. We believe that these transformations are due to acid-catalyzed heterogeneous reac

Bishop, James K.B.

377

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

E-Print Network [OSTI]

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

Hahn, David W.

378

Modeling the Direct and Indirect Effects of Atmospheric Aerosols on Tropical Cyclones  

E-Print Network [OSTI]

’ are conducted under the three aerosol scenarios: 1) the clean case with an aerosol number concentration of 200 cm-1, 2) the polluted case with a number concentration of 1000 cm-1, and 3) the aerosol radiative effects (AR) case with same aerosol concentration...

Lee, Keun-Hee

2012-02-14T23:59:59.000Z

379

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

SciTech Connect (OSTI)

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.

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

380

CSREES Nutrient Management Working Meeting  

E-Print Network [OSTI]

planning process ­ Nutrient management training ­ P-Indexes and tools developed ­ Educational materials #12Welcome CSREES Nutrient Management Working Meeting May 4 and 5, 2004 Atlanta, GA #12;University Objectives · Information Sharing Among States ­ Nutrient management regulations ­ Nutrient management

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

CARES Helps Explain Secondary Organic Aerosols  

SciTech Connect (OSTI)

What happens when urban man-made pollution mixes with what we think of as pristine forest air? To know more about what this interaction means for the climate, the Carbonaceous Aerosol and Radiative Effects Study, or CARES, field campaign was designed in 2010. The sampling strategy during CARES was coordinated with CalNex 2010, another major field campaign that was planned in California in 2010 by the California Air Resources Board (CARB), the National Oceanic and Atmospheric Administration (NOAA), and the California Energy Commission (CEC). "We found two things. When urban pollution mixes with forest pollutions we get more secondary organic aerosols," said Rahul Zaveri, FCSD scientist and project lead on CARES. "SOAs are thought to be formed primarily from forest emissions but only when they interact with urban emissions. The data is saying that there will be climate cooling over the central California valley because of these interactions." Knowledge gained from detailed analyses of data gathered during the CARES campaign, together with laboratory experiments, is being used to improve existing climate models.

Zaveri, Rahul

2014-03-28T23:59:59.000Z

382

CARES Helps Explain Secondary Organic Aerosols  

ScienceCinema (OSTI)

What happens when urban man-made pollution mixes with what we think of as pristine forest air? To know more about what this interaction means for the climate, the Carbonaceous Aerosol and Radiative Effects Study, or CARES, field campaign was designed in 2010. The sampling strategy during CARES was coordinated with CalNex 2010, another major field campaign that was planned in California in 2010 by the California Air Resources Board (CARB), the National Oceanic and Atmospheric Administration (NOAA), and the California Energy Commission (CEC). "We found two things. When urban pollution mixes with forest pollutions we get more secondary organic aerosols," said Rahul Zaveri, FCSD scientist and project lead on CARES. "SOAs are thought to be formed primarily from forest emissions but only when they interact with urban emissions. The data is saying that there will be climate cooling over the central California valley because of these interactions." Knowledge gained from detailed analyses of data gathered during the CARES campaign, together with laboratory experiments, is being used to improve existing climate models.

Zaveri, Rahul

2014-06-02T23:59:59.000Z

383

Hyperspectral Aerosol Optical Depths from TCAP Flights  

SciTech Connect (OSTI)

4STAR (Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research), the world’s first hyperspectral airborne tracking sunphotometer, acquired aerosol optical depths (AOD) at 1 Hz during all July 2012 flights of the Two Column Aerosol Project (TCAP). Root-mean square differences from AERONET ground-based observations were 0.01 at wavelengths between 500-1020 nm, 0.02 at 380 and 1640 nm and 0.03 at 440 nm in four clear-sky fly-over events, and similar in ground side-by-side comparisons. Changes in the above-aircraft AOD across 3-km-deep spirals were typically consistent with integrals of coincident in situ (on DOE Gulfstream 1 with 4STAR) and lidar (on NASA B200) extinction measurements within 0.01, 0.03, 0.01, 0.02, 0.02, 0.02 at 355, 450, 532, 550, 700, 1064 nm, respectively, despite atmospheric variations and combined measurement uncertainties. Finer vertical differentials of the 4STAR measurements matched the in situ ambient extinction profile within 14% for one homogeneous column. For the AOD observed between 350-1660 nm, excluding strong water vapor and oxygen absorption bands, estimated uncertainties were ~0.01 and dominated by (then) unpredictable throughput changes, up to +/-0.8%, of the fiber optic rotary joint. The favorable intercomparisons herald 4STAR’s spatially-resolved high-frequency hyperspectral products as a reliable tool for climate studies and satellite validation.

Shinozuka, Yohei; Johnson, Roy R.; Flynn, Connor J.; Russell, P. B.; Schmid, Beat; Redemann, Jens; Dunagan, Stephen; Kluzek, Celine D.; Hubbe, John M.; Segal-Rosenheimer, Michal; Livingston, J. M.; Eck, T.; Wagener, Richard; Gregory, L.; Chand, Duli; Berg, Larry K.; Rogers, Ray; Ferrare, R. A.; Hair, John; Hostetler, Chris A.; Burton, S. P.

2013-11-13T23:59:59.000Z

384

Particle size distribution of indoor aerosol sources  

SciTech Connect (OSTI)

As concern about Indoor Air Quality (IAQ) has grown in recent years, it has become necessary to determine the nature of particles produced by different indoor aerosol sources and the typical concentration that these sources tend to produce. These data are important in predicting the dose of particles to people exposed to these sources and it will also enable us to take effective mitigation procedures. Further, it will also help in designing appropriate air cleaners. A new state of the art technique, DMPS (Differential Mobility Particle Sizer) System is used to determine the particle size distributions of a number of sources. This system employs the electrical mobility characteristics of these particles and is very effective in the 0.01--1.0 {mu}m size range. A modified system that can measure particle sizes in the lower size range down to 3 nm was also used. Experimental results for various aerosol sources is presented in the ensuing chapters. 37 refs., 20 figs., 2 tabs.

Shah, K.B.

1990-10-24T23:59:59.000Z

385

Asthmatic responses to airborne acid aerosols  

SciTech Connect (OSTI)

Controlled exposure studies suggest that asthmatics may be more sensitive to the respiratory effects of acidic aerosols than individuals without asthma. This study investigates whether acidic aerosols and other air pollutants are associated with respiratory symptoms in free-living asthmatics. Daily concentrations of hydrogen ion (H+), nitric acid, fine particulates, sulfates and nitrates were obtained during an intensive air monitoring effort in Denver, Colorado, in the winter of 1987-88. A panel of 207 asthmatics recorded respiratory symptoms, frequency of medication use, and related information in daily diaries. We used a multiple regression time-series model to analyze which air pollutants, if any, were associated with health outcomes reported by study participants. Airborne H+ was found to be significantly associated with several indicators of asthma status, including moderate or severe cough and shortness of breath. Cough was also associated with fine particulates, and shortness of breath with sulfates. Incorporating the participants' time spent outside and exercise intensity into the daily measure of exposure strengthened the association between these pollutants and asthmatic symptoms. Nitric acid and nitrates were not significantly associated with any respiratory symptom analyzed. In this population of asthmatics, several outdoor air pollutants, particularly airborne acidity, were associated with daily respiratory symptoms.

Ostro, B.D.; Lipsett, M.J.; Wiener, M.B.; Selner, J.C. (California Department of Health Services, Berkeley (USA))

1991-06-01T23:59:59.000Z

386

The inertial and electrical effects on aerosol sampling, charging, and size distribution  

SciTech Connect (OSTI)

An experimental study was conducted to investigate the effect of particle inertia on deposition behavior near the filter cassette sampler. Field sampling cassettes were tested in a subsonic wind tunnel for 0.2, 0.5 and 0.68 m/s wind speeds to simulate indoor air environment. Fluorescein aerosols of 2 and 5 {mu}m were generated from Berglund-Liu vibrating orifice generator as test material. Sampling tests were conducted in a subsonic wind tunnel with variables of particle size, wind speed, suction velocity and orientation of sampler examined to evaluate the combined effects. Sampling efficiencies were also examined. Electrostatic force is usually used as an effective method for removing, classifying and separating aerosols according to the electrical mobilities of the particulates. On the other hand, the aerosol charging theories possess differences in the ultrafine size range and need experimental verification. The present TSI's electrostatic aerosol analyzer has particle loss problem and cannot be used as a reliable tool in achieving efficient charging. A new unipolar charger with associated electronic circuits was designed, constructed and tested. The performance of the charger is tested in terms of particle loss, uncharged particles, and the collection efficiency of the precipitator. The results were compared with other investigator's data. The log-Beta distribution function is considered to be more versatile in representing size distribution. This study discussed the method in determining the size parameters under different conditions. Also the mutability of size distribution was evaluated when particles undergo coagulation or classification processes. Comparison of evolution between log-Beta and lognormal distributions were made.

Wang, Chuenchung.

1991-01-01T23:59:59.000Z

387

The Two-Column Aerosol Project (TCAP) Science Plan  

SciTech Connect (OSTI)

The Two-Column Aerosol Project (TCAP) field campaign will provide a detailed set of observations with which to (1) perform radiative and cloud condensation nuclei (CCN) closure studies, (2) evaluate a new retrieval algorithm for aerosol optical depth (AOD) in the presence of clouds using passive remote sensing, (3) extend a previously developed technique to investigate aerosol indirect effects, and (4) evaluate the performance of a detailed regional-scale model and a more parameterized global-scale model in simulating particle activation and AOD associated with the aging of anthropogenic aerosols. To meet these science objectives, the Atmospheric Radiation Measurement (ARM) Climate Research Facility will deploy the ARM Mobile Facility (AMF) and the Mobile Aerosol Observing System (MAOS) on Cape Cod, Massachusetts, for a 12-month period starting in the summer of 2012 in order to quantify aerosol properties, radiation, and cloud characteristics at a location subject to both clear and cloudy conditions, and clean and polluted conditions. These observations will be supplemented by two aircraft intensive observation periods (IOPs), one in the summer and a second in the winter. Each IOP will deploy one, and possibly two, aircraft depending on available resources. The first aircraft will be equipped with a suite of in situ instrumentation to provide measurements of aerosol optical properties, particle composition and direct-beam irradiance. The second aircraft will fly directly over the first and use a multi-wavelength high spectral resolution lidar (HSRL) and scanning polarimeter to provide continuous optical and cloud properties in the column below.

Berkowitz, CM; Berg, LK; Cziczo, DJ; Flynn, CJ; Kassianov, EI; Fast, JD; Rasch, PJ; Shilling, JE; Zaveri, RA; Zelenyuk, A; Ferrare, RA; Hostetler, CA; Cairns, B; Russell, PB; Ervens, B

2011-07-27T23:59:59.000Z

388

Final Report for Ă?¢Ă?Â?Ă?Â?Cloud-Aerosol Physics in Super-Parameterized Atmospheric Regional Climate Simulations (CAP-SPARCS)Ă?¢Ă?Â?Ă?Âť (DE-SC0002003) for 8/15/2009 through 8/14/2012  

SciTech Connect (OSTI)

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.

Lynn M. Russell; Richard C.J. Somerville

2012-11-05T23:59:59.000Z

389

Aerodynamic size associations of natural radioactivity with ambient aerosols  

SciTech Connect (OSTI)

The aerodynamic size of /sup 214/Pb, /sup 212/Pb, /sup 210/Pb, /sup 7/Be, /sup 32/P, /sup 35/S (as SO/sub 4//sup 2 -/), and stable SO/sub 4//sup 2 -/ was measured using cascade impactors. The activity distribution of /sup 212/Pb and /sup 214/Pb, measured by alpha spectroscopy, was largely associated with aerosols smaller than 0.52 ..mu..m. Based on 46 measurements, the activity median aerodynamic diameter of /sup 212/Pb averaged 0.13 ..mu..m (sigma/sub g/ = 2.97), while /sup 214/Pb averaged 0.16 ..mu..m (sigma/sub g/ = 2.86). The larger median size of /sup 214/Pb was attributed to ..cap alpha..-recoil depletion of smaller aerosols following decay of aerosol-associated /sup 218/Po. Subsequent /sup 214/Pb condensation on all aerosols effectively enriches larger aerosols. /sup 212/Pb does not undergo this recoil-driven redistribution. Low-pressure impactor measurements indicated that the mass median aerodynamic diameter of SO/sub 4//sup 2 -/ was about three times larger than the activity median diameter /sup 212/Pb, reflecting differences in atmospheric residence times as well as the differences in surface area and volume distributions of the atmospheric aerosol. Cosmogenic radionuclides, especially /sup 7/Be, were associated with smaller aerosols than SO/sub 4//sup 2 -/ regardless of season, while /sup 210/Pb distributions in summer measurements were similar to sulfate but smaller in winter measurements. Even considering recoil following /sup 214/Po ..cap alpha..-decay, the avervage /sup 210/Pb labeled aerosol grows by about a factor of two during its atmospheric lifetime. The presence of 5 to 10% of the /sup 7/Be on aerosols greater than 1 ..mu..m was indicative of post-condensation growth, probably either in the upper atmosphere or after mixing into the boundary layer.

Bondietti, E.A.; Papastefanou, C.; Rangarajan, C.

1986-04-01T23:59:59.000Z

390

Undergraduate Program Selection Process  

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

Selection Process Undergraduate Program Selection Process Point your career towards Los Alamos Lab: work with the best minds on the planet in an inclusive environment that is rich...

391

Criteria pollutant and acid aerosol characterization study, Catano, Puerto Rico  

SciTech Connect (OSTI)

The primary objective of the Catano Criteria Pollutant and Acid Aerosol Characterization Study (CPAACS) was to measure criteria pollutant concentrations and acid aerosol concentrations in and around the Ward of Catano, Puerto Rico, during the summer of 1994. Continuous air sampling for criteria pollutants was performed at three fixed stations and one moobile station that was deployed to four locations. Air samples for acid aerosol analyses and particulate matter measurements were collected at three sites. Semicontinuous sulfate analysis was performed at the primary site. Continuous measurements of wind speed, wind direction, temperature, and relative humidity were also made at each site. The study was conducted from June 1 through September 30, 1994.

Edgerton, E.S.; Harlos, D.P.; Sune, J.M.; Akland, G.G.; Vallero, D.A.

1995-07-01T23:59:59.000Z

392

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

SciTech Connect (OSTI)

For studying the formation and photochemical/thermal reactions of aerosols relevant to the troposphere, a unique, high-volume, slow-flow, stainless steel aerosol flow system equipped with 5 UV lamps has been constructed and characterized experimentally. The total flow system length 6 is 8.5 m and includes a 1.2 m section used for mixing, a 6.1 m reaction section and a 1.2 m 7 transition cone at the end. The 45.7 cm diameter results in a smaller surface to volume ratio than is found in many other flow systems and thus reduces the potential contribution from wall reactions. The latter are also reduced by frequent cleaning of the flow tube walls which is made feasible by the ease of disassembly. The flow tube is equipped with ultraviolet lamps for photolysis. This flow system allows continuous sampling under stable conditions, thus increasing the amount of sample available for analysis and permitting a wide variety of analytical techniques to be applied simultaneously. The residence time is of the order of an hour, and sampling ports located along the length of the flow tube allow for time-resolved measurements of aerosol and gas-phase products. The system was characterized using both an inert gas (CO2) and particles (atomized NaNO3). Instruments interfaced directly to this flow system include a NOx analyzer, an ozone analyzer, relative humidity and temperature probes, a scanning mobility particle sizer spectrometer, an aerodynamic particle sizer spectrometer, a gas chromatograph-mass spectrometer, an integrating nephelometer, and a Fourier transform infrared spectrophotometer equipped with a long path (64 m) cell. Particles collected with impactors and filters at the various sampling ports can be analyzed subsequently by a variety of techniques. Formation of secondary organic aerosol from ?-pinene reactions (NOx photooxidation and ozonolysis) are used to demonstrate the capabilities of this new system.

Ezell, Michael J.; Johnson, Stanley N.; Yu, Yong; Perraud, Veronique; Bruns, Emily; Alexander, M. L.; Zelenyuk, Alla; Dabdub, Donald; Finlayson-Pitts, Barbara J.

2010-05-01T23:59:59.000Z

393

Mexico City Aerosol Analysis During Milagro Using High Resolution Aerosol Mass Spectrometry at the Urban Supersite (T0) - Part 1: Fine Particle Composition and Organic Source Apportionment.  

E-Print Network [OSTI]

Submicron aerosol was analyzed during the MILAGRO field campaign in March 2006 at the T0 urban supersite in Mexico City with a High-Resolution Aerosol Mass Spectrometer (AMS) and complementary instrumentation. Positive ...

Aiken, A. C.

394

Sensitivity of aerosol properties to new particle formation mechanism and to primary emissions in a continental-scale chemical  

E-Print Network [OSTI]

of aerosol particles and in turn their number concentration and size distribution. Aerosol particles can grow contribution from coagulation. The aerosol mass concentration, which is primarily in the accumulation mode of aerosol number concentration and size distri- bution is important for considerations of the aerosol

395

Applications of High-Resolution Electrospray Ionization Mass Spectrometry to Measurements of Average Oxygen to Carbon Ratios in Secondary Organic Aerosols  

SciTech Connect (OSTI)

The applicability of high resolution electrospray ionization mass spectrometry (HR ESI-MS) to measurements of the average oxygen to carbon ratio (O/C) in organic aerosols was investigated. Solutions with known average O/C containing up to 10 standard compounds representative of secondary organic aerosol (SOA) were analyzed and corresponding electrospray ionization efficiencies were quantified. The assumption of equal ionization efficiency commonly used in estimating O/C ratios of organic aerosols was found to be reasonably accurate. We found that the accuracy of the measured O/C ratios increases by averaging the values obtained from both (+) and (-) modes. A correlation was found between the ratio of the ionization efficiencies in the positive and negative ESI modes with the octanol-water partition constant, and more importantly, with the compound's O/C. To demonstrate the utility of this correlation for estimating average O/C values of unknown mixtures, we analyzed the ESI (+) and ESI (-) data for SOA produced by oxidation of limonene and isoprene and compared to online O/C measurements using an aerosol mass spectrometer (AMS). This work demonstrates that the accuracy of the HR ESI-MS methods is comparable to that of the AMS, with the added benefit of molecular identification of the aerosol constituents.

Bateman, Adam P.; Laskin, Julia; Laskin, Alexander; Nizkorodov, Sergey

2012-07-02T23:59:59.000Z

396

Aerosol mass spectrometry systems and methods  

DOE Patents [OSTI]

A system according to one embodiment includes a particle accelerator that directs a succession of polydisperse aerosol particles along a predetermined particle path; multiple tracking lasers for generating beams of light across the particle path; an optical detector positioned adjacent the particle path for detecting impingement of the beams of light on individual particles; a desorption laser for generating a beam of desorbing light across the particle path about coaxial with a beam of light produced by one of the tracking lasers; and a controller, responsive to detection of a signal produced by the optical detector, that controls the desorption laser to generate the beam of desorbing light. Additional systems and methods are also disclosed.

Fergenson, David P.; Gard, Eric E.

2013-08-20T23:59:59.000Z

397

Soot particle aerosol dynamics at high pressure  

SciTech Connect (OSTI)

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.

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

398

Diesel Aerosol Sampling in the Atmosphere  

SciTech Connect (OSTI)

The University of Minnesota Center for Diesel Research along with a research team including Caterpillar, Cummins, Carnegie Mellon University, West Virginia University (WVU), Paul Scherrer Institute in Switzerland, and Tampere University in Finland have performed measurements of Diesel exhaust particle size distributions under real-world dilution conditions. A mobile aerosol emission laboratory (MEL) equipped to measure particle size distributions, number concentrations, surface area concentrations, particle bound PAHs, as well as CO 2 and NO x concentrations in real time was built and will be described. The MEL was used to follow two different Cummins powered tractors, one with an older engine (L10) and one with a state-of-the-art engine (ISM), on rural highways and measure particles in their exhaust plumes. This paper will describe the goals and objectives of the study and will describe representative particle size distributions observed in roadway experiments with the truck powered by the ISM engine.

David Kittelson; Jason Johnson; Winthrop Watts; Qiang Wei; Marcus Drayton; Dwane Paulsen; Nicolas Bukowiecki

2000-06-19T23:59:59.000Z

399

aerosol content monitoring: Topics by E-print Network  

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

Rings, Jrg 2008-01-01 6 The impact of aerosols on simulated ocean temperature and heat content in the 20th century Environmental Sciences and Ecology Websites Summary: The...

400

Pressure-flow reducer for aerosol focusing devices  

DOE Patents [OSTI]

A pressure-flow reducer, and an aerosol focusing system incorporating such a pressure-flow reducer, for performing high-flow, atmosphere-pressure sampling while delivering a tightly focused particle beam in vacuum via an aerodynamic focusing lens stack. The pressure-flow reducer has an inlet nozzle for adjusting the sampling flow rate, a pressure-flow reduction region with a skimmer and pumping ports for reducing the pressure and flow to enable interfacing with low pressure, low flow aerosol focusing devices, and a relaxation chamber for slowing or stopping aerosol particles. In this manner, the pressure-flow reducer decouples pressure from flow, and enables aerosol sampling at atmospheric pressure and at rates greater than 1 liter per minute.

Gard, Eric (San Francisco, CA); Riot, Vincent (Oakland, CA); Coffee, Keith (Diablo Grande, CA); Woods, Bruce (Livermore, CA); Tobias, Herbert (Kensington, CA); Birch, Jim (Albany, CA); Weisgraber, Todd (Brentwood, CA)

2008-04-22T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

MELCOR 1. 8. 1 assessment: LACE aerosol experiment LA4  

SciTech Connect (OSTI)

The MELCOR code has been used to simulate LACE aerosol experiment LA4. In this test, the behavior of single- and double-component, hygroscopic and nonhygroscopic, aerosols in a condensing environment was monitored. Results are compared to experimental data, and to CONTAIN calculations. Sensitivity studies have been done on time step effects and machine dependencies; thermal/hydraulic parameters such as condensation on heat structures and on pool surface, and radiation heat transfer; and aerosol parameters such as number of MAEROS components and sections assumed, the degree to which plated aerosols are washed off heat structures by condensate film draining, and the effect of non-default values for shape factors and diameter limits. 9 refs., 50 figs., 13 tabs.

Kmetyk, L.N.

1991-09-01T23:59:59.000Z

402

Distinguishing Aerosol Impacts on Climate Over the Past Century  

E-Print Network [OSTI]

Figure 8a). The IE cooling increases snow/ice by about 10% (Their cooling e?ect on surface temperatures promotes ice androw), cooling from the aerosol DE increases snow/ice cover

Koch, Dorothy

2009-01-01T23:59:59.000Z

403

A review of Secondary Organic Aerosol (SOA) formation from isoprene  

E-Print Network [OSTI]

Recent field and laboratory evidence indicates that the oxidation of isoprene, (2-methyl-1,3-butadiene, C[subscript 5]H[subscript 8]) forms secondary organic aerosol (SOA). Global biogenic emissions of isoprene (600 Tg ...

Kroll, Jesse

404

atmospheric aerosol limb: Topics by E-print Network  

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

coefficient is 0.5 and then 1.0 2. For the same conditions calculate the H Weber, Rodney 5 Secondary organic aerosol 1. Atmospheric chemical mechanism for production...

405

atmospheric aerosols recorded: Topics by E-print Network  

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

coefficient is 0.5 and then 1.0 2. For the same conditions calculate the H Weber, Rodney 4 Secondary organic aerosol 1. Atmospheric chemical mechanism for production...

406

atmospheric aerosols relation: Topics by E-print Network  

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

coefficient is 0.5 and then 1.0 2. For the same conditions calculate the H Weber, Rodney 4 Secondary organic aerosol 1. Atmospheric chemical mechanism for production...

407

aerosol source apportionment: Topics by E-print Network  

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

was analyzed during the MILAGRO field campaign in March 2006 at the T0 urban supersite in Mexico City with a High-Resolution Aerosol Mass Spectrometer (AMS) and complementary...

408

aerosolized bacillus anthracis: 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 2001-01-01 118 THESE DE...

409

Aerosol-Cloud interactions : a new perspective in precipitation enhancement  

E-Print Network [OSTI]

Increased industrialization and human activity modified the atmospheric aerosol composition and size-distribution during the last several decades. This has affected the structure and evolution of clouds, and precipitation ...

Gunturu, Udaya Bhaskar

2010-01-01T23:59:59.000Z

410

aerosol optical depths: Topics by E-print Network  

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

AERONET, AVHRR and 3 MODIS 4 A. Hauser, D. Oesch have been used to 9 retrieve the spatial distribution of aerosol optical depth for 10 central Europe. At eight AERONET sites,...

411

aerosol optical depth: Topics by E-print Network  

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

AERONET, AVHRR and 3 MODIS 4 A. Hauser, D. Oesch have been used to 9 retrieve the spatial distribution of aerosol optical depth for 10 central Europe. At eight AERONET sites,...

412

aerosol strong acidity: Topics by E-print Network  

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

nucleation theories. Citation: Erupe, M. E., et al Lee, Shan-Hu 12 Neutralization of soil aerosol and its impact on the distribution of acid rain over east Asia Geosciences...

413

Results from simulated upper-plenum aerosol transport tests  

SciTech Connect (OSTI)

A series of eight aerosol transport experiments, designated as Aerosol Transport Tests (ATT) A101 through A108, has recently been completed at the Oak Ridge National Laboratory (ORNL). These tests provide a data base for validation of aerosol transport modeling used in the TRAP-MELT2 computer code (Jordan and Kuhlman, 1985), which was developed at Battelle Columbus Laboratories to calculate aerosol/fission-product transport in the reactor coolant system in postulated light-water reactor (LWR) core-melt accidents. Results from tests A103 and A104 have been summarized in a previous paper (Wright and Pattison, 1985a); the present paper discusses results from tests A105 through A108.

Wright, A.L.; Pattison, W.L.

1986-01-01T23:59:59.000Z

414

Thermophoresis and Its Thermal Parameters for Aerosol Collection  

E-Print Network [OSTI]

K/cm (a) Figure 3. (a). Thermophoretic collection ratio vs.Lin, J. , et al. , Thermophoretic deposition of particles inof a plate- to-plate thermophoretic precipitator, Aerosol

Huang, Z.

2008-01-01T23:59:59.000Z

415

aerosol particle deposition: Topics by E-print Network  

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

aerosol particles as an alternative way to determine the electron mean free path of low energy electrons in solid and liquid materials. The mean free path is obtained from fits...

416

An investigation of aerosol physical properties in Houston, Texas  

E-Print Network [OSTI]

From June through October 2001, three Tandem Differential Mobility Analyzer (TDMA) systems were operated around Houston, Texas, to obtain a large, high-quality dataset in order to explore characteristics of aerosol size distributions...

Gasparini, Roberto

2002-01-01T23:59:59.000Z

417

Climate impacts of carbonaceous and other non-sulfate aerosols: A proposed study  

SciTech Connect (OSTI)

In addition to sulfate aerosols, carbonaceous and other non-sulfate aerosols are potentially significant contributors to global climate change. We present evidence that strongly suggests that current assessments of the effects of aerosols on climate may be inadequate because major aerosol components, especially carbonaceous aerosols, are not included in these assessments. Although data on the properties and distributions of anthropogenic carbonaceous aerosols are insufficient to allow quantification of their climate impacts, the existing information suggests that climate forcing by this aerosol component may be significant and comparable to that by sulfate aerosols. We propose that a research program be undertaken to support a quantitative assessment of the role in climate forcing of non-sulfate, particularly carbonaceous, aerosols.

Andreae, M.O.; Crutzen, P.J. [Max Planck Institute for Chemistry, Mainz (Germany); Cofer, W.R. III; Hollande, J.M. [NASA Langley Research Center, Hampton, VA (United States). Atmospheric Sciences Division] [and others

1995-06-01T23:59:59.000Z

418

Balloon-borne photometric studies of the stratospheric aerosol layer after Mt. Pinatubo eruption  

SciTech Connect (OSTI)

Using Sun-tracking photometers on board balloons, the Pinatubo volcanic aerosol layer has been studied over Hyderabad (17.5 deg N) during October 1991 and April 1992. From the angular distribution of the scattered radiation intensity measurements the aerosol size parameters is derived. Over a decade of aerosol measurements at Hyderabad, aerosol extinction and number density obtained during October 1991 in the stratosphere are found to be the highest ever obtained with a distinct aerosol layer between 16 and 30 km. The derived aerosol size parameter shows layered structures. Analysis of the size parameter obtained during April 1992 indicates formation of aerosols at higher altitudes by coagulation with a subsequent reduction in the aerosol number density. The obtained results are found to agree well with that of an independent lidar measurement made over Ahmedabad (23 deg N) and with the stratospheric aerosol and gas experiment II (SAGE II) results.

Ramachandran, S.; Jayaraman, A.; Acharya, Y.B.; Subbaraya, B.H. [Physical Research Laboratory, Ahmedabad (India)

1994-08-01T23:59:59.000Z

419

Simulation of aerosol dynamics: a comparative review of mathematical models  

SciTech Connect (OSTI)

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.

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

1986-01-01T23:59:59.000Z

420

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

SciTech Connect (OSTI)

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.

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

2013-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

The modeling of aerosol dynamics during degraded core events  

SciTech Connect (OSTI)

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.

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

1989-01-01T23:59:59.000Z

422

Investigations of cloud altering effects of atmospheric aerosols using a new mixed Eulerian-Lagrangian aerosol model  

E-Print Network [OSTI]

Industry, urban development, and other anthropogenic influences have substantially altered the composition and size-distribution of atmospheric aerosol particles over the last century. This, in turn, has altered cloud ...

Steele, Henry Donnan, 1974-

2004-01-01T23:59:59.000Z

423

Real-time characterization of particle-bound polycyclic aromatic hydrocarbons in ambient aerosols and from motor-vehicle exhaust  

E-Print Network [OSTI]

Response of the Photo-Electric Aerosol Sensor (PAS) to2008 Abstract. A photo-electric aerosol sensor, a diffusionthe measured photo-electric aerosol sensor signal (fA) was

Polidori, A.; Hu, S.; Biswas, S.; Delfino, R. J; Sioutas, C.

2008-01-01T23:59:59.000Z

424

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

SciTech Connect (OSTI)

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

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

425

E-Print Network 3.0 - assessing aerosol retention Sample Search...  

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

sources of aerosol OC and assessing its transformations before... ACPD 8, 6539-6569, 2008 ESI FT-ICR MS characterization of aerosol WSOC A. S. Wozniak et al. Title... .0 License....

426

Investigation of the aerosol-cloud interaction using the WRF framework  

E-Print Network [OSTI]

. Simulations with various aerosol profiles demonstrate that the response of precipitation to the increase of aerosol concentrations is non-monotonic. The maximal cloud cover, core updraft, and maximal vertical velocity exhibit similar responses as precipitation...

Li, Guohui

2009-05-15T23:59:59.000Z

427

Aerodynamic Focusing of High-Density Aerosols D.E. Ruiza,  

E-Print Network [OSTI]

Aerodynamic Focusing of High-Density Aerosols D.E. Ruiza, , L. Gundersona , M.J. Haya , E. Merinob-density aerosol focusing for 1µm silica spheres. Preliminary results recover previous findings on aerodynamic

428

Investigation of the optical and cloud forming properties of pollution, biomass burning, and mineral dust aerosols  

E-Print Network [OSTI]

properties of a biomass burning aerosol generated from fires on the Yucatan Peninsula. Measured aerosol size distributions and size-resolved hygroscopicity and volatility were used to infer critical supersaturation distributions of the distinct particle types...

Lee, Yong Seob

2006-08-16T23:59:59.000Z

429

Climate effects of seasonally varying Biomass Burning emitted Carbonaceous Aerosols (BBCA)  

E-Print Network [OSTI]

The climate impact of the seasonality of Biomass Burning emitted Carbonaceous Aerosols (BBCA) is studied using an aerosol-climate model coupled with a slab ocean model in a set of 60-year long simulations, driven by BBCA ...

Jeong, Gill-Ran

430

E-Print Network 3.0 - aerosolized red tide Sample Search Results  

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

characteristics of desert dust and biomass burning aerosols Summary: in the right panel of Fig. 6. The aerosol scenes spectra are drawn in green, the clear sky scenes in...

431

Mechanisms of aerosol-forced AMOC variability in a state of the art climate model  

E-Print Network [OSTI]

with a new state-of-the-art Earth system model. Anthropogenic aerosols have previously been highlighted anthropogenic aerosols force a strengthening of the AMOC by up to 20% in our state-of-the-art Earth system model

432

Elucidating secondary organic aerosol from diesel and gasoline vehicles through detailed characterization of  

E-Print Network [OSTI]

Elucidating secondary organic aerosol from diesel and gasoline vehicles through detailed 19, 2012 (received for review July 22, 2012) Emissions from gasoline and diesel vehicles composition, mass distribu- tion, and organic aerosol formation potential of emissions from gasoline

Silver, Whendee

433

The effects of volcanic aerosols on mid-latitude ozone recovery  

E-Print Network [OSTI]

In this paper, comparisons between the derived Chemistry Climate Model Initiative aerosol data set to balloon sonde measurements of aerosols made in Laramie, Wyoming are made between 1979- 2012. Using the derived CCMI ...

Haskins, Jessica D

2014-01-01T23:59:59.000Z

434

E-Print Network 3.0 - aerosol pool scrubbing Sample Search Results  

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

sensing of non-aerosol absorption in cloud free atmosphere Yoram J. Kaufman,1 Summary: Remote sensing of non-aerosol absorption in cloud free atmosphere Yoram J. Kaufman,1 Oleg...

435

Aerosol effects on the photochemistry in Mexico City during MCMA-2006/MILAGRO campaign  

E-Print Network [OSTI]

In the present study, the impact of aerosols on the photochemistry in Mexico City is evaluated using the WRF-CHEM model for the period from 24 to 29 March during the MCMA-2006/MILAGRO campaign. An aerosol radiative module ...

Li, Guohui

436

Development of an atmospheric aerosol model for studies of global budgets and effects of airborne particulate material  

SciTech Connect (OSTI)

A microphysics-removal Atmospheric Aerosol Model (AAM) is developed for use in General Circulation Models (GCM) to study global budgets and effects of particulate material. In this model the particle population is assumed to be composed of a set of log-normal modes whose time evolution due to microphysical processes is described via prognostic equations for an appropriate number of moments of the particle size distribution. This newly devised technique, by making use of a small number of prognostic equations for the aerosol variables and utilizing optimized numerical procedures, renders the model computationally efficient, hence particularly suitable for use in complex 3D GCMs. Detailed parameterizations of particle coagulation, sedimentation, dry deposition, and wet removal are incorporated into the AAM.

Giorgi, F.

1986-01-01T23:59:59.000Z

437

CARES: Carbonaceous Aerosol and Radiative Effects Study Operations Plan  

SciTech Connect (OSTI)

The CARES field campaign is motivated by the scientific issues described in the CARES Science Plan. The primary objectives of this field campaign are to investigate the evolution and aging of carbonaceous aerosols and their climate-affecting properties in the urban plume of Sacramento, California, a mid-size, mid-latitude city that is located upwind of a biogenic volatile organic compound (VOC) emission region. Our basic observational strategy is to make comprehensive gas, aerosol, and meteorological measurements upwind, within, and downwind of the urban area with the DOE G-1 aircraft and at strategically located ground sites so as to study the evolution of urban aerosols as they age and mix with biogenic SOA precursors. The NASA B-200 aircraft, equipped with the High Spectral Resolution Lidar (HSRL), digital camera, and the Research Scanning Polarimeter (RSP), will be flown in coordination with the G-1 to characterize the vertical and horizontal distribution of aerosols and aerosol optical properties, and to provide the vertical context for the G-1 and ground in situ measurements.

Zaveri, RA; Shaw, WJ; Cziczo, DJ

2010-07-12T23:59:59.000Z

438

Aerosol Data Sources and Their Roles within PARAGON  

SciTech Connect (OSTI)

We briefly but systematically review major sources of aerosol data, emphasizing suites of measurements that seem most likely to contribute to assessments of global aerosol climate forcing. The strengths and limitations of existing satellite, surface, and aircraft remote-sensing systems are described, along with those of direct sampling networks and ship-based stations. It is evident that an enormous number of aerosol-related observations have been made, on a wide range of spatial and temporal sampling scales, and that many of the key gaps in this collection of data could be filled by technologies that either exist or are expected in the near future. Emphasis must be given to combining remote sensing, in situ, active and passive observations, and integrating them with aerosol chemical transport models, in order to create a more complete environmental picture having sufficient detail to address current climate-forcing questions. The Progressive Aerosol Retrieval and Assimilation Global Observing Network (PARAGON) initiative would provide an organizational framework to meet this goal.

Kahn, Ralph A.; Ogren, J. A.; Ackerman, Thomas P.; Bosenberg, Jens; Charlson, Robert J.; Diner, David J.; Holben, B. N.; Menzies, Robert T.; Miller, Mark A.; Seinfeld, John H.

2004-10-01T23:59:59.000Z

439

Secondary Aerosol: Precursors and Formation Mechanisms. Technical Report on Grant  

SciTech Connect (OSTI)

This project focused on studying trace gases that participate in chemical reactions that form atmospheric aerosols. Ammonium sulfate is a major constituent of these tiny particles, and one important pathway to sulfate formation is oxidation of dissolved sulfur dioxide by hydrogen peroxide in cloud, fog and rainwater. Sulfate aerosols influence the number and size of cloud droplets, and since these factors determine cloud radiative properties, sulfate aerosols also influence climate. Peroxide measurements, in conjunction with those of other gaseous species, can used to distinguish the contribution of in-cloud reaction to new sulfate aerosol formation from gas-phase nucleation reactions. This will lead to more reliable global climate models. We constructed and tested a new 4-channel fluorescence detector for airborne detection of peroxides. We integrated the instrument on the G-1 in January, 2006 and took a test flight in anticipation of the MAX-Mex field program, where we planned to fly under pressurized conditions for the first time. We participated in the 2006 Megacity Initiative: Local and Global Research Observations (MILAGRO) - Megacity Aerosol EXperiment â?? Mexico City (MAX-Mex) field measurement campaign. Peroxide instrumentation was deployed on the DOE G-1 research aircraft based in Veracruz, and at the surface site at Tecamac University.

Weinstein-Lloyd, Judith B

2009-05-04T23:59:59.000Z

440

E-Print Network 3.0 - arctic aerosol burden Sample Search Results  

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

and surface... generally exhibits low aerosol ... Source: National Oceanic and Atmospheric Administration, Pacific Marine Environmental Laboratory, Atmopsheric Chemistry and...

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

E-Print Network 3.0 - aerosol sellest rgivad Sample Search Results  

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

October 4, 2004 Abstract Atmospheric aerosol particles scatter and absorb shortwave (solar) radiation and Source: Brookhaven National Laboratory, Environmental Chemistry...

442

E-Print Network 3.0 - aerosol biokinetics concentrations Sample...  

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

October 4, 2004 Abstract Atmospheric aerosol particles scatter and absorb shortwave (solar) radiation and Source: Brookhaven National Laboratory, Environmental Chemistry...

443

E-Print Network 3.0 - aerosols Sample Search Results  

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

October 4, 2004 Abstract Atmospheric aerosol particles scatter and absorb shortwave (solar) radiation and Source: Brookhaven National Laboratory, Environmental Chemistry...

444

BNL-65388-AB PROPERTIES OF AMMONIATED SULFATE AEROSOLS AT LOW TEMPERATURES  

E-Print Network [OSTI]

BNL-65388-AB PROPERTIES OF AMMONIATED SULFATE AEROSOLS AT LOW TEMPERATURES: WHY ARE THE MODELS SO of Energy under Contract No. DE-AC02-98CH10886. #12;PROPERTIES OF AMMONIATED SULFATE AEROSOLS AT LOW will present a study of the properties of ammoniated sulfate aerosols ((NH4)2SO4, NH4HSO4, and in- between

445

Sensitivity of stratospheric geoengineering with black carbon to aerosol size and altitude of injection  

E-Print Network [OSTI]

Sensitivity of stratospheric geoengineering with black carbon to aerosol size and altitude geoengineering with black carbon (BC) aerosols using a general circulation model with fixed sea surface involving sulfate aerosols, black carbon geoengineering likely carries too many risks to make it a viable

446

Cloud and Aerosol Properties, Precipitable Water, and Profiles of Temperature and Water Vapor from MODIS  

E-Print Network [OSTI]

Cloud and Aerosol Properties, Precipitable Water, and Profiles of Temperature and Water Vapor from such as cloud mask, atmos- pheric profiles, aerosol properties, total precipitable water, and cloud properties vapor amount, aerosol particles, and the subsequently formed clouds [9]. Barnes et al. [2] provide

Sheridan, Jennifer

447

Significant reduction of surface solar irradiance induced by aerosols in a suburban region in northeastern China  

E-Print Network [OSTI]

Significant reduction of surface solar irradiance induced by aerosols in a suburban region in northeastern China Xiangao Xia,1 Hongbin Chen,1 Zhanqing Li,1,2 Pucai Wang,1 and Jiankai Wang1 Received 25 May region in northeastern China. Aerosol properties derived from Sun photometer measurements and aerosol

Li, Zhanqing

448

Speciation of Fe in ambient aerosol and cloudwater  

SciTech Connect (OSTI)

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.

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

1996-08-15T23:59:59.000Z

449

Aerosols and Clouds: In Cahoots to Change Climate  

SciTech Connect (OSTI)

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."

Berg, Larry

2014-03-29T23:59:59.000Z

450

Aerosols and Clouds: In Cahoots to Change Climate  

ScienceCinema (OSTI)

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."

Berg, Larry

2014-06-02T23:59:59.000Z

451

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

SciTech Connect (OSTI)

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.

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

452

Origin of atmospheric aerosols at the Pierre Auger Observatory using studies of air mass trajectories in South America  

E-Print Network [OSTI]

The Pierre Auger Observatory is making significant contributions towards understanding the nature and origin of ultra-high energy cosmic rays. One of its main challenges is the monitoring of the atmosphere, both in terms of its state variables and its optical properties. The aim of this work is to analyze aerosol optical depth $\\tau_{\\rm a}(z)$ values measured from 2004 to 2012 at the observatory, which is located in a remote and relatively unstudied area of the Pampa Amarilla, Argentina. The aerosol optical depth is in average quite low - annual mean $\\tau_{\\rm a}(3.5~{\\rm km})\\sim 0.04$ - and shows a seasonal trend with a winter minimum - $\\tau_{\\rm a}(3.5~{\\rm km})\\sim 0.03$ -, and a summer maximum - $\\tau_{\\rm a}(3.5~{\\rm km})\\sim 0.06$ -, and an unexpected increase from August to September - $\\tau_{\\rm a}(3.5~{\\rm km})\\sim 0.055$). We computed backward trajectories for the years 2005 to 2012 to interpret the air mass origin. Winter nights with low aerosol concentrations show air masses originating from t...

Curci, Gabriele

2014-01-01T23:59:59.000Z

453

Correcting transport errors during advection of aerosol and cloud moment sequences in eulerian models  

SciTech Connect (OSTI)

Moment methods are finding increasing usage for simulations of particle population balance in box models and in more complex flows including two-phase flows. These highly efficient methods have nevertheless had little impact to date for multi-moment representation of aerosols and clouds in atmospheric models. There are evidently two reasons for this: First, atmospheric models, especially if the goal is to simulate climate, tend to be extremely complex and take many man-years to develop. Thus there is considerable inertia to the implementation of novel approaches. Second, and more fundamental, the nonlinear transport algorithms designed to reduce numerical diffusion during advection of various species (tracers) from cell to cell, in the typically coarse grid arrays of these models, can and occasionally do fail to preserve correlations between the moments. Other correlated tracers such as isotopic abundances, composition of aerosol mixtures, hydrometeor phase, etc., are subject to this same fate. In the case of moments, this loss of correlation can and occasionally does give rise to unphysical moment sets. When this happens the simulation can come to a halt. Following a brief description and review of moment methods, the goal of this paper is to present two new approaches that both test moment sequences for validity and correct them when they fail. The new approaches work on individual grid cells without requiring stored information from previous time-steps or neighboring cells.

McGraw R.

2012-03-01T23:59:59.000Z

454

Review: [Untitled] Reviewed Work(s)  

E-Print Network [OSTI]

Review: [Untitled] Reviewed Work(s): Dodonæus in Japan: Translation and the Scientific Mind to leading academic journals and scholarly literature from around the world. The Archive is supported-for-profit organization with a mission to help the scholarly community take advantage of advances in technology. For more

Elman, Benjamin

455

QEP WORKING GROUP CHARGES Assessment Working Group  

E-Print Network [OSTI]

and a framework that details timelines, leadership, resource allocation, and an assessment plan that is clearlyQEP WORKING GROUP CHARGES Assessment Working Group The topic of the QEP should fit should be supported by a thorough understanding of the institutional context and by assessment data

Liu, Paul

456

Distinguishing Aerosol Impacts on Climate Over the Past Century  

SciTech Connect (OSTI)

Aerosol direct (DE), indirect (IE), and black carbon-snow albedo (BAE) effects on climate between 1890 and 1995 are compared using equilibrium aerosol-climate simulations in the Goddard Institute for Space Studies General Circulation Model coupled to a mixed layer ocean. Pairs of control(1890)-perturbation(1995) with successive aerosol effects allow isolation of each effect. The experiments are conducted both with and without concurrent changes in greenhouse gases (GHG's). A new scheme allowing dependence of snow albedo on black carbon snow concentration is introduced. The fixed GHG experiments global surface air temperature (SAT) changed -0.2, -1.0 and +0.2 C from the DE, IE, and BAE. Ice and snow cover increased 1.0% from the IE and decreased 0.3% from the BAE. These changes were a factor of 4 larger in the Arctic. Global cloud cover increased by 0.5% from the IE. Net aerosol cooling effects are about half as large as the GHG warming, and their combined climate effects are smaller than the sum of their individual effects. Increasing GHG's did not affect the IE impact on cloud cover, however they decreased aerosol effects on SAT by 20% and on snow/ice cover by 50%; they also obscure the BAE on snow/ice cover. Arctic snow, ice, cloud, and shortwave forcing changes occur mostly during summer-fall, but SAT, sea level pressure, and long-wave forcing changes occur during winter. An explanation is that aerosols impact the cryosphere during the warm-season but the associated SAT effect is delayed until winter.

Koch, Dorothy; Menon, Surabi; Del Genio, Anthony; Ruedy, Reto; Alienov, Igor; Schmidt, Gavin A.

2008-08-22T23:59:59.000Z

457

High-Resolution Electrospray Ionization Mass Spectrometry Analysis of Water- Soluble Organic Aerosols Collected with a Particle into Liquid Sampler  

SciTech Connect (OSTI)

This work demonstrates the utility of a particle-into-liquid sampler (PILS) a technique traditionally used for identification of inorganic ions present in ambient or laboratory aerosols for the analysis of water soluble organic aerosol (OA) using high resolution electrospray ionization mass spectrometry (HR ESI-MS). Secondary organic aerosol (SOA) was produced from 0.5 ppm mixing ratios of limonene and ozone in a 5 m3 Teflon chamber. SOA was collected simultaneously using a traditional filter sampler and a PILS. The filter samples were later extracted with either water or acetonitrile, while the aqueous PILS samples were analyzed directly. In terms of peak intensities, types of detectable compounds, average O:C ratios, and organic mass to organic carbon ratios, the resulting high resolution mass spectra were essentially identical for the PILS and filter based samples. SOA compounds extracted from both filter/acetonitrile extraction and PILS/water extraction accounted for >95% of the total ion current in ESI mass spectra. This similarity was attributed to high solubility of limonene SOA in water. In contrast, significant differences in detected ions and peak abundances were observed for pine needle biomass burning organic aerosol (BBOA) collected with PILS and filter sampling. The water soluble fraction of BBOA is considerably smaller than for SOA, and a number of unique peaks were detectable only by the filter/acetonitrile method. The combination of PILS collection with HR-ESI-MS analysis offers a new approach for molecular analysis of the water-soluble organic fraction in biogenic SOA, aged photochemical smog, and BBOA.

Bateman, Adam P.; Nizkorodov, Serguei; Laskin, Julia; Laskin, Alexander

2010-10-01T23:59:59.000Z

458

Final Project Report - ARM CLASIC CIRPAS Twin Otter Aerosol  

SciTech Connect (OSTI)

The NOAA/ESRL/GMD aerosol group made three types of contributions related to airborne measurements of aerosol light scattering and absorption for the Cloud and Land Surface Interaction Campaign (CLASIC) in June 2007 on the Twin Otter research airplane operated by the Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS). GMD scientists served as the instrument mentor for the integrating nephelometer and particle soot absorption photometer (PSAP) on the Twin Otter during CLASIC, and were responsible for (1) instrument checks/comparisons; (2) instrument trouble shooting/repair; and (3) data quality control (QC) and submittal to the archive.

John A. Ogren

2010-04-05T23:59:59.000Z

459

Mercury capture by aerosol transformation in combustion environments. Appendix 5  

SciTech Connect (OSTI)

Aerosol transformation of elemental mercury by oxidizing mercury in the air is investigated in this study by varying temperature and residence time. The experimental results show that mercury oxidation is not important at the temperature range and time scale studied. The rate of mercury oxidation is too slow that the capture of mercury vapor by transforming it into mercury oxide in aerosol phase is not practical in real systems. Studies are needed for alternative approaches to capture mercury vapor such as the use of sorbent materials.

NONE

1997-02-01T23:59:59.000Z

460

Thermophoretic separation of aerosol particles from a sampled gas stream  

SciTech Connect (OSTI)

A method for separating gaseous samples from a contained atmosphere that includes aerosol particles uses the step of repelling particles from a gas permeable surface or membrane by heating the surface to a temperature greater than that of the surrounding atmosphere. The resulting thermophoretic forces maintain the gas permeable surface clear of aerosol particles. The disclosed apparatus utilizes a downwardly facing heated plate of gas permeable material to combine thermophoretic repulsion and gravity forces to prevent particles of any size from contacting the separating plate surfaces.

Postma, Arlin K. (Halfway, OR)

1986-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol processes working" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

ARM: 10-minute TEMPORARY Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm  

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

10-minute TEMPORARY Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

Sivaraman, Chitra; Flynn, Connor

462

Aerosol Formation from High-Pressure Sprays for Supporting the Safety Analysis for the Hanford Waste Treatment and Immobilization Plant  

SciTech Connect (OSTI)

The Waste Treatment and Immobilization Plant (WTP) at Hanford is being designed and built to pretreat and vitrify waste currently stored in underground tanks at Hanford. One of the postulated events in the hazard analysis for the WTP is a breach in process piping that produces a pressurized spray with small droplets that can be transported into ventilation systems. Literature correlations are currently used for estimating the generation rate and size distribution of aerosol droplets in postulated spray releases. These correlations, however, are based on results obtained from small engineered nozzles using Newtonian liquids that do not contain slurry particles and thus do not accurately represent the fluids and breaches in the WTP. A test program was developed to measure the generation rate of droplets suspended in a test chamber and droplet size distribution from a range of prototypic sprays. A novel test method was developed to allow measurement of sprays from small to very large breaches and also includes the effect of aerosol generation from splatter when the spray impacts on walls. Results show that the aerosol generation rate increases with increasing the orifice area, though with a weaker dependence on orifice area than the currently-used correlation. A comparison of water sprays to slurry sprays with 8 to 20 wt% gibbsite or boehmite particles shows that the presence of slurry particles depresses the release fraction compared to water for droplets above 10 ?m and increases the release fraction below this droplet size.

Gauglitz, Phillip A.; Mahoney, Lenna A.; Schonewill, Philip P.; Bontha, Jagannadha R.; Blanchard, Jeremy; Kurath, Dean E.; Daniel, Richard C.; Song, Chen

2013-03-05T23:59:59.000Z

463

Soft ionization of thermally evaporated hypergolic ionic liquid aerosols  

SciTech Connect (OSTI)

Isolated ion pairs of a conventional ionic liquid, 1-Ethyl-3-Methyl-Imidazolium Bis(trifluoromethylsulfonyl)imide ([Emim+][Tf2N?]), and a reactive hypergolic ionic liquid, 1- Butyl-3-Methyl-Imidazolium Dicyanamide ([Bmim+][Dca?]), are generated by vaporizing ionic liquid submicron aerosol particles for the first time; the vaporized species are investigated by dissociative ionization with tunable vacuum ultraviolet (VUV) light, exhibiting clear intact cations, Emim+ and Bmim+, presumably originating from intact ion pairs. Mass spectra of ion pair vapor from an effusive source of the hypergolic ionic liquid show substantial reactive decomposition due to the internal energy of the molecules emanating from the source. Photoionization efficiency curves in the near threshold ionization region of isolated ion pairs of [Emim+][Tf2N?] ionic liquid vapor are compared for an aerosol source and an effusive source, revealing changes in the appearance energy due to the amount of internal energy in the ion pairs. The aerosol source has a shift to higher threshold energy (~;;0.3 eV), attributed to reduced internal energy of the isolated ion pairs. The method of ionic liquid submicron aerosol particle vaporization, for reactive ionic liquids such as hypergolic species, is a convenient, thermally ?cooler? source of isolated intact ion pairs in the gas phase compared to effusive sources.

University of California; ERC, Incorporated, Edwards Air Force Base; Air Force Research Laboratory, Edwards Air Force Base; National Synchrotron Radiation Research Center (NSRRC); Koh, Christine J.; Liu, Chen-Lin; Harmon, Christopher W.; Strasser, Daniel; Golan, Amir; Kostko, Oleg; Chambreau, Steven D.; L.Vaghjiani, Ghanshyam; Leone, Stephen R.

2012-03-16T23:59:59.000Z

464

Lubricating Oil Dominates Primary Organic Aerosol Emissions from Motor Vehicles  

E-Print Network [OSTI]

Lubricating Oil Dominates Primary Organic Aerosol Emissions from Motor Vehicles David R. Worton to "fresh" lubricating oil. The gas chromatography retention time data indicates that the cycloalkane ring with lubricating oil being the dominant source from both gasoline and diesel-powered vehicles, with an additional

Cohen, Ronald C.

465

aerosol test chamber: Topics by E-print Network  

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

aerosol test chamber 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 IFE Chamber Technology Testing...

466

aerosol simulant test: Topics by E-print Network  

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

aerosol simulant test 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 6, 75197562, 2006 Simulating...

467

AIRBORNE HIGH SPECTRAL RESOLUTION LIDAR MEASUREMENTS OF ATMOSPHERIC AEROSOLS  

E-Print Network [OSTI]

the evolution and transport of pollution from Mexico City. The second major experiment was the Texas Air Quality Union 2007 Joint Assembly Acapulco, Mexico May 22-25, 2007 Environmental Sciences Department Research Observations (MILAGRO) /Megacity Aerosol Experiment in Mexico City (MAX

468

Boreal forests, aerosols and the impacts on clouds and climate  

E-Print Network [OSTI]

of energy, momentum, water, carbon dioxide and other trace gas and aerosol species (figure 1). Through due to the absorption of the Sun's heat by the dark forest canopy. However, these studies ignored shown in figure 2) have a dark canopy (with low albedo) that obscures the snow-covered ground (with high

Spracklen, Dominick

469

CLOUD DROPLET NUCLEATION AND ITS CONNECTION TO AEROSOL PROPERTIES  

E-Print Network [OSTI]

CLOUD DROPLET NUCLEATION AND ITS CONNECTION TO AEROSOL PROPERTIES STEPHEN E. SCHWARTZ Environmental in cloud-free conditions and indirectly, by increasing concentratiol1S of cloud droplets thereby enhancing cloud shortwave reflectivity. These effecls are thought to be significant in the context of changes

470

Black carbon aerosols and the third polar ice cap  

SciTech Connect (OSTI)

Recent thinning of glaciers over the Himalayas (sometimes referred to as the third polar region) have raised concern on future water supplies since these glaciers supply water to large river systems that support millions of people inhabiting the surrounding areas. Black carbon (BC) aerosols, released from incomplete combustion, have been increasingly implicated as causing large changes in the hydrology and radiative forcing over Asia and its deposition on snow is thought to increase snow melt. In India BC emissions from biofuel combustion is highly prevalent and compared to other regions, BC aerosol amounts are high. Here, we quantify the impact of BC aerosols on snow cover and precipitation from 1990 to 2010 over the Indian subcontinental region using two different BC emission inventories. New estimates indicate that Indian BC emissions from coal and biofuel are large and transport is expected to expand rapidly in coming years. We show that over the Himalayas, from 1990 to 2000, simulated snow/ice cover decreases by {approx}0.9% due to aerosols. The contribution of the enhanced Indian BC to this decline is {approx}36%, similar to that simulated for 2000 to 2010. Spatial patterns of modeled changes in snow cover and precipitation are similar to observations (from 1990 to 2000), and are mainly obtained with the newer BC estimates.

Menon, Surabi; Koch, Dorothy; Beig, Gufran; Sahu, Saroj; Fasullo, John; Orlikowski, Daniel

2010-04-15T23:59:59.000Z

471

Measurements of aerosol vertical profiles and optical properties during INDOEX  

E-Print Network [OSTI]

Markowicz,5 James R. Campbell,6 James D. Spinhirne,7 Howard R. Gordon,2 and James E. Johnson3 Received 5 field phase. Measurements were made from two platforms: the NOAA ship R/V Ronald H. Brown. Markowicz, J. R. Campbell, J. D. Spinhirne, H. R. Gordon, and J. E. Johnson, Measurements of aerosol

472

AT631, Spring 2011 Introduction to Atmospheric Aerosols  

E-Print Network [OSTI]

. Pandis, Atmospheric Chemistry and Physics: From Air Pollution to Climate Change, Wiley-Interscience, 2006AT631, Spring 2011 Introduction to Atmospheric Aerosols Tuesdays 9-9:50 AM, 212B ACRC Wednesdays, Lab, 1-4 PM, ACB 10 Instructor: Prof. Sonia Kreidenweis Atmospheric Chemistry Bldg., Room 19 491

473

Correction to “Hyperspectral Aerosol Optical Depths from TCAP Flights”  

SciTech Connect (OSTI)

In the paper “Hyperspectral aerosol optical depths from TCAP flights” by Y. Shinozuka et al. (Journal of Geophysical Research: Atmospheres, 118, doi:10.1002/2013JD020596, 2013), Tables 1 and 2 were published with the column heads out of order. Tables 1 and 2 are published correctly here. The publisher regrets the error.

Shinozuka, Yohei; Johnson, Roy R.; Flynn, Connor J.; Russell, P. B.; Schmid, Beat; Redemann, Jens; Dunagan, Stephen; Kluzek, Celine D.; Hubbe, John M.; Segal-Rosenheimer, Michal; Livingston, J. M.; Eck, T.; Wagener, Richard; Gregory, L.; Chand, Duli; Berg, Larry K.; Rogers, Ray; Ferrare, R. A.; Hair, John; Hostetler, Chris A.; Burton, S. P.

2014-02-16T23:59:59.000Z

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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

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