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Note: This page contains sample records for the topic "aerosol chemical speciation" from the National Library of EnergyBeta (NLEBeta).
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1

Development of a Wet-Chemical Method for the Speciation of Iron in Atmospheric Aerosols  

Science Journals Connector (OSTI)

The ability to quantify the chemical and physical forms of transition metals in atmospheric particulate matter (PM) is essential in determining potential human health and ecological effects. ... As an application of this method to mobile source emissions, size-resolved PM10 samples were collected at the inlet and outlet of the Caldecott Motor Vehicle Tunnel in northern California. ... A series of 6 h samples was obtained at the inlets and outlets of Bore 1 (approximately 4% Diesel, 96% gasoline vehicles) and Bore 2 (gasoline only). ...

Brian J. Majestic; James J. Schauer; Martin M. Shafer; Jay R. Turner; Philip M. Fine; Manisha Singh; Constantinos Sioutas

2006-02-24T23:59:59.000Z

2

Overview of Detailed Chemical Speciation and Particle Sizing...  

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

Detailed Chemical Speciation and Particle Sizing for Diesel Exhaust, Both Real Time and Filter Based Measurements Overview of Detailed Chemical Speciation and Particle Sizing for...

3

Chemical speciation of radionuclides migrating in groundwaters  

SciTech Connect

In order to more accurately predict the rates and mechanisms of radionuclide migration from low-level waste disposal facilities via groundwater transport, ongoing studies are being conducted at field sites at Chalk River Laboratories to identify and characterize the chemical speciation of mobile, long-lived radionuclides migrating in groundwaters. Large-volume water sampling techniques are being utilized to separate and concentrate radionuclides into particular, cationic, anionic, and nonionic chemical forms. Most radionuclides are migrating as soluble, anionic species that appear to be predominantly organoradionuclide complexes. Laboratory studies utilizing anion exchange chromatography have separated several anionically complexed radionuclides, e.g., {sup 60}Co and {sup 106}Ru, into a number of specific compounds or groups of compounds. Further identification of the anionic organoradionuclide complexes is planned utilizing high resolution mass spectrometry. Large-volume ultra-filtration experiments are characterizing the particulate forms of radionuclides being transported in these groundwaters.

Robertson, D.; Schilk, A.; Abel, K.; Lepel, E.; Thomas, C.; Pratt, S. [Pacific Northwest Lab., Richland, WA (United States); Cooper, E.; Hartwig, P.; Killey, R. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.

1994-04-01T23:59:59.000Z

4

Frontiers in Assessing the Role of Chemical Speciation and Natural Attenuation on the Bioavailability  

E-Print Network (OSTI)

1 Frontiers in Assessing the Role of Chemical Speciation and Natural Attenuation components. Applications of these techniques to assess metal and organic chemical sorption/release, natural widely employed to provide an indirect assessment ofchemical speciation and association ofcontaminants

Sparks, Donald L.

5

Mercury Release and Speciation in Chemical Looping Combustion of Coal  

Science Journals Connector (OSTI)

Mercury Release and Speciation in Chemical Looping Combustion of Coal ... In the in situ Gasification Chemical Looping Combustion of coal (iG-CLC), the fuel is gasified in situ in the fuel reactor and gasification products are converted to CO2 and H2O by reaction with the oxygen carrier. ... This work is the first study on mercury release in Chemical Looping Combustion of coal. ...

T. Mendiara; M. T. Izquierdo; A. Abad; P. Gayán; F. García-Labiano; L. F. de Diego; J. Adánez

2014-03-06T23:59:59.000Z

6

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

NLE Websites -- All DOE Office Websites (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...

7

CHEMICAL SPECIATION OF GOLD IN ARSENOPYRITE  

Science Journals Connector (OSTI)

...ores. Hyperfine Interact. 70 , 945-948. ---, --- Wang, N. (1995): On the chemical state of combined gold in...X-ray synchrotron microprobe techniques and applications. In Synchroton Methods in Clay Science (D.G. Schulze, J.W. Stucki...

Louis J. Cabri; Matthew Newville; Robert A. Gordon; E. Daryl Crozier; Stephen R. Sutton; Greg McMahon; De-Tong Jiang

8

Chemical Speciation of Chromium in Drilling Muds  

SciTech Connect

Drilling muds are made of bentonite and other clays, and/or polymers, mixed with water to the desired viscosity. Without the drilling muds, corporations could not drill for oil and gas and we would have hardly any of the fuels and lubricants considered essential for modern industrial civilization. There are hundreds of drilling muds used and some kinds of drilling muds contain chromium. The chemical states of chromium in muds have been studied carefully due to concerns about the environmental influence. However it is difficult to determine the chemical state of chromium in drilling muds directly by conventional analytical methods. We have studied the chemical form of chromium in drilling muds by using a laboratory XAFS system and a synchrotron facility.

Taguchi, Takeyoshi [X-ray Research Laboratory, RIGAKU Corporation, 3-9-12 Matsubara-cho, Akishima-shi, Tokyo 196-8666 (Japan); Yoshii, Mitsuru [Mud Technical Center, Telnite Co., Ltd., 1-2-14 Ohama, Sakata-shi, Yamagata 998-0064 (Japan); Shinoda, Kohzo [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai-shi, Miyagi 980-8577 (Japan)

2007-02-02T23:59:59.000Z

9

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

NLE Websites -- All DOE Office Websites (Extended Search)

Aerosol on Clouds Summary: chemical composition and mixing stateTime-Resolved Aerosol Collector CCSEMEDX (ASP) Single particle... Sizer CCN spectrum Aerosol absorptionDRI...

10

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

NLE Websites -- All DOE Office Websites (Extended Search)

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

11

Effect of Chemical Speciation on Toxicity of Mercury to Escherichia coli Biofilms and Planktonic Cells  

Science Journals Connector (OSTI)

Effect of Chemical Speciation on Toxicity of Mercury to Escherichia coli Biofilms and Planktonic Cells ... charged forms of mercuric chloride (HgCl3-/HgCl42-) induced less light prodn. ...

Isaac Najera; Chu-Ching Lin; Golenaz Adeli Kohbodi; Jennifer A. Jay

2005-03-25T23:59:59.000Z

12

The application of a chemical equilibrium model, SOLTEQ, to predict the chemical speciations in stabilized/solidified waste forms  

E-Print Network (OSTI)

THE APPLICATION OI' A CHEMICAL EQUILIBRIUM MODEL, SOLTEQ, TO PREDICT THK CHEMICAL SPKCIATIONS IN STABILIZED/SOLIDIFIED WASTE FORMS A Thesis by JOO-YANG PARK 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 December 1994 Major Subject: Civil Engineering THE APPLICATION OF A CHEMICAL EQUILIBRIUM MODEL, SOLTEQ, TO PREDICT THE CHEMICAL SPECIATIONS IN STABILIZED/SOLIDIFIED WASTE FORMS A Thesis...

Park, Joo-Yang

1994-01-01T23:59:59.000Z

13

Chemical Composition and Cloud Nucleation Ability of Marine Aerosol  

E-Print Network (OSTI)

This study is focused on the chemical composition and cloud nucleation ability of marine aerosol based on two cruise researches over Pacific Ocean and North Atlantic Ocean respectively. Implications of CLAW hypothesis and the factors influencing its...

Deng, Chunhua

2013-12-12T23:59:59.000Z

14

Chemical and physical speciation of mercury in Offatts Bayou: A seasonally anoxic bayou in Galveston Bay  

SciTech Connect

A chemical equilibrium model was used to predict the solution speciation of dissolved mercury (Hg) in the stratified water column of Offatts Bayou, a subestuary in Galveston Bay, Texas, which undergoes seasonal anoxia in bottom waters. Chemical equilibrium modeling was conducted using conditional stability constants and concentrations of Hg-complexing organic ligands experimentally determined by competitive ligand equilibration methods. Dissolved Hg complexation was dominated by interactions with sulfide and dissolved organic matter (DOM) (HOHgHS0, HOHgHS(DOM), HgSHS2, and HgS 2{ 2 ) at all depths. Sulfide and glutathione competed for methylmercury (MeHg) complexation in oxic layers; in anoxic waters, sulfide complexation dominated MeHg speciation. The particle–water distribution coefficient (Kd) of Hg decreased in the anoxic layer of the water column, where the dissolved sulfide concentration increased, providing evidence that sulfide complexation influences the solubility of Hg. The solubility of MeHg was elevated in the anoxic as compared to the oxic layers, and this distributional feature was coincident with a change in the solution speciation of dissolved MeHg from glutathione/sulfide complexation in the oxic layers to a predominantly sulfide complexation in the anoxic layers. Maximum enrichment of Hg, MeHg, and iron (Fe) in suspended particulate matter was observed in the lower layer of the pycnocline, most likely resulting from formation of insoluble Fe oxide, which scavenged dissolved Hg sulfide and MeHg-sulfide species. The concomitant decrease in dissolved inorganic Hg, Fe, and sulfide in the anoxic layers is suggested to result from scavenging of inorganic Hg by FeS, which is in accordance with the Hg speciation model. Overall, Hg cycling in the water column of Offatts Bayou was associated with sulfide and DOM complexation, Fe dissolution/precipitation, water column production of MeHg, and/or efflux of MeHg from anoxic sediment.

Han, Seunghee; Lehman, Ronald D.; Choe, Key-Young; Gill, Gary A.

2007-07-01T23:59:59.000Z

15

Raman spectroscopic studies of chemical speciation in calcium chloride melts  

SciTech Connect

Raman spectroscopy was applied to CaCl2 melts at 900 degrees C under both non-electrolyzed and electrolyzed conditions. The later used titania cathodes supplied by TIMET, Inc. and graphite anodes. Use of pulse-gating to collect the Raman spectra successfully eliminated any interference from black-body radiation and other stray light. The spectrum of molten CaCl2 exhibited no distinct, resolvable bands that could be correlated with a calcium chloride complex similar to MgCl42- in MgCl2 melts. Rather, the low frequency region of the spectrum was dominated by a broad “tail” arising from collective oscillations of both charge and mass in the molten salt “network.” Additions of both CaO and Ca at concentrations of a percent or two resulted in no new features in the spectra. Addition of CO2, both chemically and via electrolysis at concentrations dictated by stability and solubility at 900 degrees C and 1 bar pressure, also produced no new bands that could be correlated with either dissolved CO2 or the carbonate ion. These results indicated that Raman spectroscopy, at least under the conditions evaluated in the research, was not well suited for following the reactions and coordination chemistry of calcium ions, nor species such as dissolved metallic Ca and CO2 that are suspected to impact current efficiency in titanium electrolysis cells using molten CaCl2. Raman spectra of TIMET titania electrodes were successfully obtained as a function of temperature up to 900 degrees C, both in air and in-situ in CaCl2 melts. However, spectra of these electrodes could only be obtained when the material was in the unreduced state. When reduced, either with hydrogen or within an electrolysis cell, the resulting electrodes exhibited no measurable Raman bands under the conditions used in this work.

Windisch, Charles F.; Lavender, Curt A.

2005-02-01T23:59:59.000Z

16

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

NLE Websites -- All DOE Office Websites (Extended Search)

American Chemical... Element Methods, Aerosols, Air Pollution Modeling, ... Source: Consortium for Fossil Fuel Science, C1 Chemistry Program Collection: Fossil Fuels 36...

17

Chemical Speciation of Sulfur in Marine Cloud Droplets and Particles: Analysis of Individual Particles from Marine Boundary Layer over the California Current  

SciTech Connect

Detailed chemical speciation of the dry residue particles from individual cloud droplets and interstitial aerosol collected during the Marine Stratus Experiment (MASE) was performed using a combination of complementary microanalysis techniques. Techniques include computer controlled scanning electron microscopy with energy dispersed analysis of X-rays (CCSEM/EDX), time-of-flight secondary ionization mass spectrometry (TOF-SIMS), and scanning transmission X-ray microscopy with near edge X-ray absorption fine structure spectroscopy (STXM/NEXAFS). Samples were collected at the ground site located in Point Reyes National Seashore, approximately 1 km from the coast. This manuscript focuses on the analysis of individual particles sampled from air masses that originated over the open ocean and then passed through the area of the California current located along the northern California coast. Based on composition, morphology, and chemical bonding information, two externally mixed, distinct classes of sulfur containing particles were identified: chemically modified (aged) sea salt particles and secondary formed sulfate particles. The results indicate substantial heterogeneous replacement of chloride by methanesulfonate (CH3SO3-) and non-sea salt sulfate (nss-SO42-) in sea-salt particles with characteristic ratios of nss-S/Na>0.10 and CH3SO3-/nss-SO42->0.6.

William R. Wiley Environmental Sciences Laboratory, Pacific Northwest National Laboratory; Gilles, Mary K; Hopkins, Rebecca J.; Desyaterik, Yury; Tivanski, Alexei V.; Zaveri, Rahul A.; Berkowitz, Carl M.; Tyliszczak, Tolek; Gilles, Mary K.; Laskin, Alexander

2008-03-12T23:59:59.000Z

18

RETENTION AND CHEMICAL SPECIATION OF URANIUM IN A WETLAND ON THE SAVANNAH RIVER SITE  

SciTech Connect

Uranium speciation and retention mechanism onto Savannah River Site (SRS) wetland sediments was studied using batch (ad)sorption experiments, sequential extraction desorption tests and U L{sub 3}-edge X-ray absorption near-edge structure (XANES) spectroscopy of contaminated wetland sediments. U was highly retained by the SRS wetland sediments. In contrast to other similar but much lower natural organic matter (NOM) sediments, significant sorption of U onto the SRS sediments was observed at pH <4 and pH >8. Sequential extraction tests indicated that the U(VI) species were primarily associated with the acid soluble fraction (weak acetic acid extractable) and NOM fraction (Na-pyrophosphate extractable). Uranium L3- edge XANES spectra of the U-retained sediments were nearly identical to that of uranyl acetate. The primary oxidation state of U in these sediments was as U(VI), and there was little evidence that the high sorptive capacity of the sediments could be ascribed to abiotic or biotic reduction to the less soluble U(IV) species. The molecular mechanism responsible for the high U retention in the SRS wetland sediments is likely related to the chemical bonding of U to organic carbon.

Li, D.; CHANG, H.: SEAMAN, J.; Jaffe, P.; Groos, P.; Jiang, D.; Chen, N.; Lin, J.; Arthur, Z.; Scheckel, K.; Kaplan, D.

2013-06-17T23:59:59.000Z

19

Chemical and Physical Properties of Atmospheric Aerosols (a) A Case Study in the Unique Properties of Agricultural Aerosols (b) The Role of Chemical Composition in Ice Nucleation during the Arctic Spring  

E-Print Network (OSTI)

dataset is reported for these physical and chemical properties of agricultural aerosols appropriate for use in a site-specific emission inventory. The emission rate and transport of the aerosols are also discussed. In addition, mixing ratios of total...

Moon, Seong-Gi

20

New Chemical Aerosol Characterization Methods- Examples Using Agricultural and Urban Airborne Particulate Matter  

E-Print Network (OSTI)

quality (Sweeten et al., 1998). However, accurate data for a number of regulated pollutants is lacking, and more measurements of agricultural aerosols are needed. A better understanding of the chemical composition of PM is also necessary for a complete...

Zhou, Lijun

2010-10-12T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

Effect of Fly Ash on Solidification and Heavy Metals Chemical Speciation of Sludge  

Science Journals Connector (OSTI)

In order to explore new municipal sewage sludge treatment method and reduce its harm for environment, fly ash discarded from power plant was used as conditioner in sludge treatment in the paper. The properties of sewage sludge were changed after adding ... Keywords: fly ash, sludge, compressive strength, heavy metal, speciation

Yongjian Piao; Mingsong Wu; Xun Xu; Qingliang Zhao; Fugui Zhang; Nanqi Ren

2011-01-01T23:59:59.000Z

22

Chemical speciation of neptunium in spent fuel. Annual report for period 15 August 1999 to 15 August 2000  

SciTech Connect

(B204) This project will examine the chemical speciation of neptunium in spent nuclear fuel. The R&D fields covered by the project include waste host materials and actinide chemistry. Examination of neptunium is chosen since it was identified as a radionuclide of concern by the NERI workshop. Additionally, information on the chemical form of neptunium in spent fuel is lacking. The identification of the neptunium species in spent fuel would allow a greater scientific based understanding of its long-term fate and behavior in waste forms. Research to establish the application and development of X-ray synchrotrons radiation (XSR) techniques to determine the structure of aqueous, adsorbed, and solid actinide species of importance to nuclear considerations is being conducted at Argonne. These studies extend current efforts within the Chemical Technology Division at Argonne National Laboratory to investigate actinide speciation with more conventional spectroscopic and solids characterization (e.g. SEM, TEM, and XRD) methods. Our project will utilize all these techniques for determining neptunium speciation in spent fuel. We intend to determine the chemical species and oxidation state of neptunium in spent fuel and alteration phases. Different types of spent fuel will be examined. Once characterized, the chemical behavior of the identified neptunium species will be evaluated if it is not present in the literature. Special attention will be given to the behavior of the neptunium species under typical repository near-field conditions (elevated temperature, high pH, varying Eh). This will permit a timely inclusion of project results into near-field geochemical models. Additionally, project results and methodologies have applications to neptunium in the environment, or treatment of neptunium containing waste. Another important aspect of this project is the close cooperation between a university and a national laboratory. The PI has a transuranic laboratory at MIT where students can perform spectroscopic and radiochemical experiments. Through the ANL partner, students can have additional experience performing research in a DOE setting. This will provide a unique and constructive opportunity for developing quality graduate students with experience and expertise in handling actinides. Our ability to produce experienced actinide scientists is currently restricted by the dearth of radiochemistry and nuclear research at universities. Regardless of all else, future researchers must be trained and educated if the United States is to maintain a leadership role in nuclear technology. This project provides such an opportunity.

Ken Czerwinski; Don Reed

2000-09-01T23:59:59.000Z

23

HEMISPHERIC-SCALE CHEMICAL AND MICROPHYSICAL AEROSOL MODEL  

E-Print Network (OSTI)

Dignon Bates/Lamb DRY DEPOSITION Wesely WET DEPOSITION Berkowitz/Hales CHEMISTRY Gas Aqueous SO2 + OH [OH dependent Size Resolved Wesely WET DEPOSITION Berkowitz/Hales CHEMISTRY Gas Phase Aqueous Phase SO2 AEROSOL;Anthropogenic Anthropogenic #12;by Production Mechanism Gas phase Aqueous Phase Primary October 15, 1986 at 6 UT

Schwartz, Stephen E.

24

DISSERTATION THE OPTICAL, CHEMICAL, AND PHYSICAL PROPERTIES OF AEROSOLS AND  

E-Print Network (OSTI)

AND GASES EMITTED BY THE LABORATORY COMBUSTION OF WILDLAND FUELS Biomass burning is a major source of trace BY THE LABORATORY COMBUSTION OF WILDLAND FUELS Submitted by Gavin R. McMeeking Department of Atmospheric Science PROPERTIES OF AEROSOL AND GASES EMITTED BY THE LABORATORY COMBUSTION OF WILDLAND FUELS BE ACCEPTED

Pierce, Jeffrey

25

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

26

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

SciTech Connect

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

27

Time-and size-resolved chemical composition of submicron particles in Pittsburgh: Implications for aerosol sources and processes  

E-Print Network (OSTI)

Time- and size-resolved chemical composition of submicron particles in Pittsburgh: Implications), Time- and size-resolved chemical composition of submicron particles in Pittsburgh: Implications] Atmospheric aerosols have important adverse impacts on human health [Dockery et al., 1993; Pope et al., 2002

Jimenez, Jose-Luis

28

Semi-Continuous Measurements of Aerosol Chemical Composition During the Summer 2002 Yosemite National Park Special Study  

SciTech Connect

Semi-continuous measurements of fine particle composition were made over a period of several weeks in summer 2002 in Yosemite National Park, California. These included measurement of aerosol ionic composition (by PILS- Particle-Into-Liquid System) and aerosol carbon (by dual wavelength aethalometer and an R&P particulate carbon monitor). The data reveal that aerosol composition at the site is highly :variable in time, with a strong diurnal cycle. Interestingly, however, different diurnal cycles were sometimes observed for different chemical constituents of the particles. Organic carbon was observed to dominate fine particle mass, with some periods apparently associated with influx of smoke from wildfires in the western U.S. Measurements of fine particle carbon isotopes revealed the fraction of carbon from biogenic sources to range from approximately 73 to 95%. The ionic fraction of the aerosol was usually dominated by ammoniated sulfate. During most periods, PM{sub 2.5} nitrate was found primarily in sea salt particles from which chloride had been displaced. Strong variations in the extent of ammonia neutralization of sulfate were also observed. The ability to observe rapid changes in aerosol composition using these semi-continuous aerosol composition measurements is helpful for understanding the dynamic chemical composition of fine particles responsible for regional haze.

Collette, J; Lee, T; Heath, J; Carrico, C; Herckes, P; Engling, G; McMeeking, G; Kreidenweis, S; Day, D; Malm, W; Cahill, T

2003-02-16T23:59:59.000Z

29

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

30

Mercury Speciation in the Presence of Polysulfides  

E-Print Network (OSTI)

Mercury Speciation in the Presence of Polysulfides J E N N Y A Y L A J A Y , * , F R A N C¸ O I Environmental mercury methylation appears modulated by sulfide concentrations, possibly via changes in mercury, there has been much recent interest in quantifying the chemical speciation and lipid solubility of mercury

Morel, François M. M.

31

Molecular Characterization of Biomass Burning Aerosols Using...  

NLE Websites -- All DOE Office Websites (Extended Search)

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

32

Laboratory investigation of chemical and physical properties of soot-containing aerosols  

E-Print Network (OSTI)

SO4-coated soot aerosols; (3) effect of H2SO4 coating on scattering and extinction properties of soot particles. A low-pressure laminar-flow reactor, coupled to ion driftchemical ionization mass spectrometry (ID-CIMS) detection, is used to study...

Zhang, Dan

2006-08-16T23:59:59.000Z

33

Physicochemical Characterization of Capstone Depleted Uranium Aerosols III: Morphologic and Chemical Oxide Analyses  

SciTech Connect

The impact of depleted uranium (DU) penetrators against an armored target causes erosion and fragmentation of the penetrators, the extent of which is dependent on the thickness and material composition of the target. Vigorous oxidation of the DU particles and fragments creates an aerosol of DU oxide particles and DU particle agglomerations combined with target materials. Aerosols from the Capstone DU aerosol study, in which vehicles were perforated by DU penetrators, were evaluated for their oxidation states using X-ray diffraction (XRD) and particle morphologies using scanning electron microscopy/energy dispersive spectrometry (SEM/EDS). The oxidation state of a DU aerosol is important as it offers a clue to its solubility in lung fluids. The XRD analysis showed that the aerosols evaluated were a combination primarily of U3O8 (insoluble) and UO3 (relatively more soluble) phases, though intermediate phases resembling U4O9 and other oxides were prominent in some samples. Analysis of particle residues in the micrometer-size range by SEM/EDS provided microstructural information such as phase composition and distribution, fracture morphology, size distribution, and material homogeneity. Observations from SEM analysis show a wide variability in the shapes of the DU particles. Some of the larger particles appear to have been fractured (perhaps as a result of abrasion and comminution); others were spherical, occasionally with dendritic or lobed surface structures. Amorphous conglomerates containing metals other than uranium were also common, especially with the smallest particle sizes. A few samples seemed to contain small chunks of nearly pure uranium metal, which were verified by EDS to have a higher uranium content exceeding that expected for uranium oxides. Results of the XRD and SEM/EDS analyses were used in other studies described in this issue of The Journal of Health Physics to interpret the results of lung solubility studies and in selecting input parameters for dose assessments.

Krupka, Kenneth M.; Parkhurst, MaryAnn; Gold, Kenneth; Arey, Bruce W.; Jenson, Evan D.; Guilmette, Raymond A.

2009-03-01T23:59:59.000Z

34

Integrating biomass, sulphate and sea-salt aerosol responses into a microphysical chemical parcel model: implications for climate studies  

Science Journals Connector (OSTI)

...John Schellnhuber Integrating biomass, sulphate and sea-salt aerosol...biomass burning. In Global biomass burning: atmospheric, climatic...particles from African savanna combustion experiments. Atmos. Res...99)00329-5 . Integrating biomass, sulphate and sea-salt aerosol...

2007-01-01T23:59:59.000Z

35

Experimental determination of the speciation, partitioning, and release of perrhenate as a chemical surrogate for pertechnetate from a sodalite-bearing multiphase ceramic waste form  

SciTech Connect

A key component to closing the nuclear fuel cycle is the storage and disposition of nuclear waste in geologic systems. Multiphase ceramic waste forms have been studied extensively as a potential host matrix for nuclear waste. Understanding the speciation, partitioning, and release behavior of radionuclides immobilized in multiphase ceramic waste forms is a critical aspect of developing the scientific and technical basis for nuclear waste management. In this study, we evaluated a sodalite-bearing multiphase ceramic waste form (i.e., fluidized-bed steam reform sodium aluminosilicate [FBSR NAS] product) as a potential host matrix for long-lived radionuclides, such as technetium (99Tc). The FBSR NAS material consists primarily of nepheline (ideally NaAlSiO4), anion-bearing sodalites (ideally M8[Al6Si6O24]X2, where M refers to alkali and alkaline earth cations and X refers to monovalent anions), and nosean (ideally Na8[AlSiO4]6SO4). Bulk X-ray absorption fine structure analysis of the multiphase ceramic waste form, suggest rhenium (Re) is in the Re(VII) oxidation state and has partitioned to a Re-bearing sodalite phase (most likely a perrhenate sodalite Na8[Al6Si6O24](ReO4)2). Rhenium was added as a chemical surrogate for 99Tc during the FBSR NAS synthesis process. The weathering behavior of the FBSR NAS material was evaluated under hydraulically unsaturated conditions with deionized water at 90 ?C. The steady-state Al, Na, and Si concentrations suggests the weathering mechanisms are consistent with what has been observed for other aluminosilicate minerals and include a combination of ion exchange, network hydrolysis, and the formation of an enriched-silica surface layer or phase. The steady-state S and Re concentrations are within an order of magnitude of the nosean and perrhenate sodalite solubility, respectively. The order of magnitude difference between the observed and predicted concentration for Re and S may be associated with the fact that the anion-bearing sodalites contained in the multiphase ceramic matrix are present as mixed-anion sodalite phases. These results suggest the multiphase FBSR NAS material may be a viable host matrix for long-lived, highly mobilie radionuclides which is a critical aspect in the management of nuclear waste.

Pierce, Eric M.; Lukens, Wayne W.; Fitts, Jeff. P.; Jantzen, Carol. M.; Tang, G.

2013-12-01T23:59:59.000Z

36

Correlations Between Optical, Chemical and Physical Properties...  

NLE Websites -- All DOE Office Websites (Extended Search)

Biomass Burn Aerosols. Correlations Between Optical, Chemical and Physical Properties of Biomass Burn Aerosols. Abstract: Single scattering albedo (?) and Angstrom...

37

The Influence of Fog and Airmass History on Aerosol Optical, Physical and Chemical Properties at Pt. Reyes National Seashore  

SciTech Connect

This paper presents an analysis of the aerosol chemical composition, optical properties and size distributions for a range of conditions encountered during a field measurement campaign conducted between July 7-29, 2005 at Point Reyes National Seashore, north of San Francisco, CA. Observations are partitioned into one-hour periods when conditions were ‘clear’ or ‘foggy’ to identify evidence of cloud processing of aerosols. During the first half of the campaign (July 7-18), conditions at the site were largely maritime. However flow during the second half of the campaigns (July 18-29) was influenced by a thermal trough that added a cyclonic twist to the incoming marine air, bringing it from the south with a more extensive over-land trajectory. Neither flow regime was associated with air coming from the San Francisco Bay area to the south. Measurements by an Aerodyne aerosol mass spectrometer (AMS) of the equivalent molar ratio of ammonium to the sum of sulfate, nitrate and chloride made before the onset of the thermal trough on July 18th were associated with acidic or near-neutral particles. Measurements made after July 18th appear to have excess ammonium. The AMS measurements of mass loading were an order of magnitude less than those reported by a nearby IMPROVE station. However, the AMS measures only non-refractory particles between 0.1 µm and 1 µm, which would not include sea salt. In contrast, the IMPROVE station employs filter-based techniques to measure mass for all particles < 2.5 µm. Assuming chlorine is associated with large sea salt particles at Pt. Reyes and removing this value from the IMPROVE data resulted in good agreement in the total mass fraction between these two techniques,, indicating the importance of sea salt mass in particles greater than 1 µm. Model calculations of the equilibrium gas-phase mixing ratio of NH3 suggest very high values which we attribute to agricultural practices within the park. Reported as an incidental finding is evidence for the cloud droplet activation of large particles (diameter >0.2 mm) with a corresponding reduction in the single scattering albedo of the non-activated particles, followed by a return in the particle size spectrum to the pre-fog conditions immediately afterwards.

Berkowitz, Carl M.; Berg, Larry K.; Yu, Xiao-Ying; Alexander, M. L.; Laskin, Alexander; Zaveri, Rahul A.; Jobson, Bertram Thomas; Andrews, Elisabeth; Ogren, John A.

2011-04-05T23:59:59.000Z

38

THE LIFETIME OF AEROSOLS IN AMBIENT AIR: CONSIDERATION OF THE EFFECTS OF SURFACTANTS AND CHEMICAL REACTIONS  

SciTech Connect

The relatively long lifetime of droplets in atmospheric haze and fog in comparison with similar droplets of pure water is attributed to the presence of a monolayer of surfactant film and to the accumulation Of soluble salts from chemical reactions. The lifetime of these droplets is a significant factor in the evaluation of the role of heterogeneous aqueous chemical reactions occurring in the troposphere. Several mechanisms of SO{sub 2} oxidation in the presence of liquid water are investigated. It is shown that soot-catalyzed oxidation of sulfur dioxide could be responsible for the high level of sulfate concentration observed in the coastal industrial areas.

Toossi, R.; Novakov, T.

1984-04-01T23:59:59.000Z

39

An Improved Equilibrium-Kinetics Speciation Algorithm For Redox Reactions  

Open Energy Info (EERE)

Improved Equilibrium-Kinetics Speciation Algorithm For Redox Reactions Improved Equilibrium-Kinetics Speciation Algorithm For Redox Reactions In Variably Saturated Subsurface Flow Systems Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: An Improved Equilibrium-Kinetics Speciation Algorithm For Redox Reactions In Variably Saturated Subsurface Flow Systems Details Activities (0) Areas (0) Regions (0) Abstract: Reactive chemical transport occurs in a variety of geochemical environments, and over a broad range of space and time scales. Efficiency of the chemical speciation and water-rock-gas interaction calculations is important for modeling field-scale multidimensional reactive transport problems. An improved efficient model, REACT, for simulating water-rock-gas interaction under equilibrium and kinetic conditions, has been developed.

40

Measurement of elemental speciation by liquid chromatography -- inductively coupled plasma mass spectrometry (LC-ICP-MS) with the direct injection nebulizer (DIN)  

SciTech Connect

This thesis is divided into 4 parts: elemental speciation, speciation of mercury and lead compounds by microbore column LC-ICP-MS with direct injection nebulization, spatially resolved measurements of size and velocity distributions of aerosol droplets from a direct injection nebulizer, and elemental speciation by anion exchange and size exclusion chromatography with detection by ICP-MS with direct injection nebulization. Tabs, figs, refs.

Shum, S.

1993-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

DEVELOPMENT OF FINE PARTICULATE EMISSION FACTORS AND SPECIATION PROFILES FOR OIL AND GAS-FIRED COMBUSTION SYSTEMS  

SciTech Connect

In 1997, the United States Environmental Protection Agency (EPA) promulgated new National Ambient Air Quality Standards (NAAQS) for particulate matter, including for the first time particles with aerodynamic diameter smaller than 2.5 micrometers ({micro}m) referred to as PM2.5. PM2.5 in the atmosphere also contributes to reduced atmospheric visibility, which is the subject of existing rules for siting emission sources near Class 1 areas and new Regional Haze rules. There are few existing data regarding emissions and characteristics of fine aerosols from oil, gas and power generation industry combustion sources, and the information that is available is generally outdated and incomplete. Traditional stationary source air emission sampling methods tend to underestimate or overestimate the contribution of the source to ambient aerosols because they do not properly account for primary aerosol formation, which occurs after the gases leave the stack. Primary aerosol includes both filterable particles that are solid or liquid aerosols at stack temperature plus those that form as the stack gases cool through mixing and dilution processes in the plume downwind of the source. These deficiencies in the current methods can have significant impacts on regulatory decision-making. PM2.5 measurement issues were extensively reviewed by the American Petroleum Institute (API) (England et al., 1998), and it was concluded that dilution sampling techniques are more appropriate for obtaining a representative particulate matter sample from combustion systems for determining PM2.5 emission rate and chemical speciation. Dilution sampling is intended to collect aerosols including those that condense and/or react to form solid or liquid aerosols as the exhaust plume mixes and cools to near-ambient temperature immediately after the stack discharge. These techniques have been widely used in recent research studies. For example, Hildemann et al. (1994) and McDonald et al. (1998) used filtered ambient air to dilute the stack gas sample followed by 80-90 seconds residence time to allow aerosol formation and growth to stabilize prior to sample collection and analysis. More accurate and complete emissions data generated using the methods developed in this program will enable more accurate source-receptor and source apportionment analysis for PM2.5 National Ambient Air Quality Standards (NAAQS) implementation and streamline the environmental assessment of oil, gas and power production facilities. The overall goals of this program were to: (1) Develop improved dilution sampling technology and test methods for PM2.5 mass emissions and speciation measurements, and compare results obtained with dilution and traditional stationary source sampling methods. (2) Develop emission factors and speciation profiles for emissions of fine particulate matter, especially organic aerosols, for use in source-receptor and source apportionment analyses. (3) Identify and characterize PM2.5 precursor compound emissions that can be used in source-receptor and source apportionment analyses.

Glenn C. England

2004-10-20T23:59:59.000Z

42

aerosols | EMSL  

NLE Websites -- All DOE Office Websites (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...

43

Reflective Aerosols and the Greenhouse Effect  

Science Journals Connector (OSTI)

The contributions of atmospheric aerosols to add to either a climate-warming effect or climate-cooling effect depend on the chemical composition of the aerosol and the local environment. The best estimation is...

Kathryn E. Kautzman

2014-07-01T23:59:59.000Z

44

Environmental Speciation of Actinides  

Science Journals Connector (OSTI)

We also provide an overview of uranium or plutonium speciation and remediation strategies across a range of contaminated sites (e.g., Hanford, WA; Oak Ridge, TN; Rifle, CO; Fernald, OH; Fry Canyon, UT; and Rocky Flats, CO). ... (12) As a result, the majority of actinides, in particular plutonium, neptunium, americium, and curium, are released to the environment from human activities. ... (234-236) The following discussion compares two cases of uranium contamination in the 200 and 300 Areas, respectively, in order to illustrate how the original waste–rock interactions and the physical distribution of uranium-bearing phases are closely coupled with the ultimate speciation and mobility of uranium. ...

Kate Maher; John R. Bargar; Gordon E. Brown, Jr.

2012-11-08T23:59:59.000Z

45

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

46

Iron Speciation and Mixing in Single Aerosol Particles from the...  

NLE Websites -- All DOE Office Websites (Extended Search)

the global carbon budget and climate. Particles collected on Okinawa Island during an atmospheric pollution transport event from China were analyzed using complementary single...

47

Bird song, ecology and speciation  

Science Journals Connector (OSTI)

...In this way song learning increases the reliability of song as...This could lead to a dramatic increase in the reliability of song...design for vocaliza- tions: quality in the woods, consistency...speciation in animals: new wine in old bottles. Trends Ecol...

2002-01-01T23:59:59.000Z

48

ARM - Field Campaign - Aerosol Life Cycle IOP at BNL  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsAerosol Life Cycle IOP at BNL govCampaignsAerosol Life Cycle IOP at BNL Campaign Links Images Wiki 2011 ASR STM Presentation: Sedlacek 2011 ASR STM Presentation: Springston 2010 ASR Fall Meeting: Sedlacek News, June 14, 2011: Next-generation Aerosol-sampling Stations to Head for India Related Campaigns Aerosol Life Cycle: Chemical Ionization Mass Spectrometer - CIMS 2011.07.10, Lee, OSC Aerosol Life Cycle: HR-ToF-AMS 2011.06.15, Zhang, OSC Aerosol Life Cycle: ARM Mobile Facility 2 Aerosol Observing System 2011.06.15, Sedlacek, OSC Aerosol Life Cycle: UV-APS and Nano-SMPS 2011.06.10, Hallar, OSC Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Aerosol Life Cycle IOP at BNL 2011.06.01 - 2011.08.31 Lead Scientist : Arthur Sedlacek For data sets, see below.

49

Continuous air monitor for alpha-emitting aerosol particles  

SciTech Connect

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

50

Mercury Speciation in Piscivorous Fish from Mining-impacted Reservoirs  

NLE Websites -- All DOE Office Websites (Extended Search)

Mercury Speciation in Piscivorous Mercury Speciation in Piscivorous Fish from Mining-impacted Reservoirs Mercury toxicity generates environmental concerns in diverse aquatic systems because methylmercury enters the water column in diverse ways then biomagnifies through food webs. At the apex of many freshwater food webs, piscivorous fish can then extend that trophic transfer and potential for neurotoxicity to wildlife and humans. Mining activities, particularly those associated with the San Francisco Bay region, can generate both point and non-point mercury sources. Replicate XANES analyses on largemouth bass and hybrid striped bass from Guadalupe Reservoir (GUA), California and Lahontan Reservoir (LAH), Nevada, were performed to determine predominant chemical species of mercury accumulated by high-trophic-level piscivores that are exposed to elevated mercury in both solution and particulate phases in the water column.

51

Mercury speciation in floodplain soils and sediments along a contaminated river transect  

SciTech Connect

A novel mercury-specific sequential extraction procedure (SEP) for the assessment of mercury (Hg) speciation in soils and sediments, with emphasis on studying the interaction between Hg and organic matter (OM), was developed and tested. It was applied to determine Hg speciation in floodplain topsoils and surface sediments along the Hg-contaminated part of the river Elbe, and to simultaneously derive some information on the (re)mobilization potentials for Hg from these matrices. The majority of the total Hg in the ecosystem today is bound in the floodplains, which also still geographically reflect the historic emission record. Most of the Hg in both matrices is bound strongly to OM, suggesting low availability. However, distinct differences between Hg speciation in the floodplain soils and sediments were also discovered. Mercury deposited in the floodplains shows speciation patterns that indicate stronger fixation compared with Hg in the sediments. This difference is attributed to the association of Hg with larger quantities of OM, which presumably also has higher molecular weight (MW). By comparison, Hg in the sediments was distributed among weaker binding forms, which are more likely to liberate Hg. Particularly, sediments showed a total lack of sulfidic binding forms for Hg. Pronounced geographical trends were detected in the Hg speciation along the river transect, with a general downstream shift from weaker to stronger binding forms, probably due to increased association with OM. These studies indicate that Hg speciation in riverine ecosystems is dynamic and reflects the chemical mechanisms underlying (bio) geochemical processes like distribution and transport.

Wallschlaeger, D.; Desai, M.V.M.; Spengler, M. [GKSS Forschungszentrum GmbH, Geesthacht (Germany). Inst. fuer Physikalische und Chemische Analytik; Wilken, R.D. [Johannes-Gutenberg-Univ., Mainz (Germany). Inst. of Geosciences

1998-09-01T23:59:59.000Z

52

On The Importance of Organic Oxygen for Understanding Organic Aerosol  

NLE Websites -- All DOE Office Websites (Extended Search)

On The Importance of Organic Oxygen for Understanding Organic Aerosol On The Importance of Organic Oxygen for Understanding Organic Aerosol Particles Title On The Importance of Organic Oxygen for Understanding Organic Aerosol Particles Publication Type Journal Article Year of Publication 2006 Authors Pang, Yanbo, B. J. Turpin, and Lara A. Gundel Journal Journal of Aerosol Science and Technology Volume 40 Start Page Chapter Pagination 128-133 Abstract This study shows how aerosol organic oxygen data could provide new and independent information about organic aerosol mass, aqueous solubility of organic aerosols, formation of secondary organic aerosol (SOA) and the relative contributions of anthropogenic and biogenic sources. For more than two decades atmospheric aerosol organic mass concentration has usually been estimated by multiplying the measured carbon content by an assumed organic mass (OM)-to-organic carbon (OC ) factor of 1.4. However, this factor can vary from 1.0 to 2.5 depending on location. This great uncertainty about aerosol organic mass limits our understanding of the influence of organic aerosol on climate, visibility and health.New examination of organic aerosol speciation data shows that the oxygen content is the key factor responsible for the observed range in the OM-to-OC factor. When organic oxygen content is excluded, the ratio of non-oxygen organic mass to carbon mass varies very little across different environments (1.12 to 1.14). The non-oxygen-OM-to-non-oxygen OC factor for all studied sites (urban and non-urban) is 1.13± 0.02. The uncertainty becomes an order of magnitude smaller than the uncertainty in the best current estimates of organic mass to organic carbon ratios (1.6± 0.2 for urban and 2.1± 0.2 for non-urban areas). When aerosol organic oxygen data become available, organic aerosol mass can be quite accurately estimated using just OC and organic oxygen (OO) without the need to know whether the aerosol is fresh or aged. In addition, aerosol organic oxygen data will aid prediction of water solubility since compounds with OO-to-OC higher than 0.4 have water solubilities higher than 1g per 100 g water

53

HYBRID SPECIATION IN WILD SUNFLOWERS1  

E-Print Network (OSTI)

HYBRID SPECIATION IN WILD SUNFLOWERS1 Loren H. Rieseberg2 ABSTRACT Hybrid speciation refers to the establishment of novel hybrid genotypes that are reproductively isolated from their parental species, in some instances new hybrid species arise and become reproductively isolated without a change

Rieseberg, Loren

54

Density functional theory study on the interstitial chemical shifts of main-group-element centered hexazirconium halide clusters; synthetic control of speciation in [(Zr6ZCl12)] (Z = B, C)-based mixed ligand complexes  

E-Print Network (OSTI)

. For carbide-, boride-, and nitride-centered carbonyl- ligated clusters of the later transition metals, such exceptional chemical shifts have also been observed and are quite comparable to data for hexazirconium clusters.79-86 A number of correlative... make the main contributions to paramagnetic shielding. Kaupp calculated 13C chemical shift tensors for interstitial carbides of a series of transition metal carbonyl clusters using sum-over-states density functional perturbation theory (SOS-DFPT)90...

Shen, Jingyi

2005-08-29T23:59:59.000Z

55

Importance of aerosol composition, mixing state, and morphology for heterogeneous ice nucleation: A combined field and laboratory approach  

E-Print Network (OSTI)

In this study chemical compositions of background aerosol and ice nuclei were examined through laboratory investigations using Raman spectroscopy and field measurements by single-particle mass spectrometry. Aerosol sampling ...

Baustian, Kelly J.

56

Composition and Reactions of Atmospheric Aerosol Particles  

NLE Websites -- All DOE Office Websites (Extended Search)

Composition and Reactions of Composition and Reactions of Atmospheric Aerosol Particles Composition and Reactions of Atmospheric Aerosol Particles Print Wednesday, 29 June 2005 00:00 Microscopic aerosol particles in the atmosphere contain carbonaceous components from mineral dust and combustion emissions released from around the world. How long these tiny particles remain in the atmosphere can have a huge impact on the global climate. Measurements based on high-resolution scanning transmission x-ray images obtained at the ALS have revealed chemical reactions on and in atmospheric aerosol particles that caused particle growth while changing organic composition by 13 to 24% per day, an oxidation rate significantly slower than is currently used in atmospheric models. Since oxidation has a strong effect on particle lifetime in the atmosphere, these results will help climate scientists refine the computer models used to predict climate change.

57

Composition and Reactions of Atmospheric Aerosol Particles  

NLE Websites -- All DOE Office Websites (Extended Search)

Composition and Reactions of Atmospheric Aerosol Particles Print Composition and Reactions of Atmospheric Aerosol Particles Print Microscopic aerosol particles in the atmosphere contain carbonaceous components from mineral dust and combustion emissions released from around the world. How long these tiny particles remain in the atmosphere can have a huge impact on the global climate. Measurements based on high-resolution scanning transmission x-ray images obtained at the ALS have revealed chemical reactions on and in atmospheric aerosol particles that caused particle growth while changing organic composition by 13 to 24% per day, an oxidation rate significantly slower than is currently used in atmospheric models. Since oxidation has a strong effect on particle lifetime in the atmosphere, these results will help climate scientists refine the computer models used to predict climate change.

58

BNL | Two-Column Aerosol Program (TCAP)  

NLE Websites -- All DOE Office Websites (Extended Search)

Two-Column Aerosol Project (TCAP) Two-Column Aerosol Project (TCAP) There remain many key knowledge gaps despite advances in the scientific understanding of how aerosols and clouds evolve and affect climate. Many climatically important processes depend on particles that undergo continuous changes within a size range spanning a few nanometers to a few microns, and with compositions that consist of a variety of carbonaceous materials, soluble inorganic salts and acids and insoluble mineral dust. Primary particles, which are externally-mixed when emitted, are subject to coagulation and chemical changes associated with the condensation of semi-volatile gases to their surface resulting in a spectrum of compositions or mixing-states with a range of climate-affecting optical and hygroscopic properties. The numerical treatments of aerosol transformation

59

Composition and Reactions of Atmospheric Aerosol Particles  

NLE Websites -- All DOE Office Websites (Extended Search)

Composition and Reactions of Atmospheric Aerosol Particles Print Composition and Reactions of Atmospheric Aerosol Particles Print Microscopic aerosol particles in the atmosphere contain carbonaceous components from mineral dust and combustion emissions released from around the world. How long these tiny particles remain in the atmosphere can have a huge impact on the global climate. Measurements based on high-resolution scanning transmission x-ray images obtained at the ALS have revealed chemical reactions on and in atmospheric aerosol particles that caused particle growth while changing organic composition by 13 to 24% per day, an oxidation rate significantly slower than is currently used in atmospheric models. Since oxidation has a strong effect on particle lifetime in the atmosphere, these results will help climate scientists refine the computer models used to predict climate change.

60

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

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

Speciation of Uranium in Biologically Reduced Sediments in the...  

NLE Websites -- All DOE Office Websites (Extended Search)

Speciation of Uranium in Biologically Reduced Sediments in the Old Rifle Aquifer Wednesday, May 16, 2012 - 1:30pm SSRL Conference Room 137-322 Juan S. Lezama Pacheco The speciation...

62

ARM - Field Campaign - Biogenic Aerosols - Effects on Clouds and Climate:  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsBiogenic Aerosols - Effects on Clouds and Climate: govCampaignsBiogenic Aerosols - Effects on Clouds and Climate: FIGAERO-ToF-CIMS Instrument in Hyytiala with AMF-2 Related Campaigns Biogenic Aerosols- Effects on Clouds and Climate 2014.02.01, Petäjä, AMF Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Biogenic Aerosols - Effects on Clouds and Climate: FIGAERO-ToF-CIMS Instrument in Hyytiala with AMF-2 2014.04.01 - 2014.06.01 Lead Scientist : Joel Thornton Description The ultimate goal of this work is to connect field and laboratory observations of organic aerosol chemical and physical properties during the nascent growth stage to the diurnal and vertical distributions of aerosol abundance measured over the boreal forest by the ARM Mobile Facility 2

63

Persistent sensitivity of Asian aerosol to emissions of nitrogen oxides  

E-Print Network (OSTI)

We use a chemical transport model and its adjoint to examine the sensitivity of secondary inorganic aerosol formation to emissions of precursor trace gases from Asia. Sensitivity simulations indicate that secondary inorganic ...

Kharol, S. K.

64

Selenium Speciation and Management in Wet FGD Systems  

SciTech Connect

This report discusses results from bench- and pilot-scale simulation tests conducted to determine the factors that impact selenium speciation and phase partitioning in wet FGD systems. The selenium chemistry in wet FGD systems is highly complex and not completely understood, thus extrapolation and scale-up of these results may be uncertain. Control of operating parameters and application of scrubber additives have successfully demonstrated the avoidance or decrease of selenite oxidation at the bench and pilot scale. Ongoing efforts to improve sample handling methods for selenium speciation measurements are also discussed. Bench-scale scrubber tests explored the impacts of oxidation air rate, trace metals, scrubber additives, and natural limestone on selenium speciation in synthetic and field-generated full-scale FGD liquors. The presence and concentration of redox-active chemical species as well as the oxidation air rate contribute to the oxidation-reduction potential (ORP) conditions in FGD scrubbers. Selenite oxidation to the undesirable selenate form increases with increasing ORP conditions, and decreases with decreasing ORP conditions. Solid-phase manganese [Mn(IV)] appeared to be the significant metal impacting the oxidation of selenite to selenate. Scrubber additives were tested for their ability to inhibit selenite oxidation. Although dibasic acid and other scrubber additives showed promise in early clear liquor (sodium based and without calcium solids) bench-scale tests, these additives did not show strong inhibition of selenite oxidation in tests with higher manganese concentrations and with slurries from full-scale wet FGD systems. In bench-tests with field liquors, addition of ferric chloride at a 250:1 iron-to-selenium mass ratio sorbed all incoming selenite to the solid phase, although addition of ferric salts had no impact on native selenate that already existed in the field slurry liquor sample. As ORP increases, selenite may oxidize to selenate more rapidly than it sorbs to ferric solids. Though it was not possible to demonstrate a decrease in selenium concentrations to levels below the project�¢����s target of 50 ���µg/L during pilot testing, some trends observed in bench-scale testing were evident at the pilot scale. Specifically, reducing oxidation air rate and ORP tends to either retain selenium as selenite in the liquor or shift selenium phase partitioning to the solid phase. Oxidation air flow rate control may be one option for managing selenium behavior in FGD scrubbers. Units that cycle load widely may find it more difficult to impact ORP conditions with oxidation air flow rate control alone. Because decreasing oxidation air rates to the reaction tank showed that all �¢����new�¢��� selenium reported to the solids, the addition of ferric chloride to the pilot scrubber could not show further improvements in selenium behavior. Ferric chloride addition did shift mercury to the slurry solids, specifically to the fine particles. Several competing pathways may govern the reporting of selenium to the slurry solids: co-precipitation with gypsum into the bulk solids and sorption or co-precipitation with iron into the fine particles. Simultaneous measurement of selenium and mercury behavior suggests a holistic management strategy is best to optimize the fate of both of these elements in FGD waters. Work conducted under this project evaluated sample handling and analytical methods for selenium speciation in FGD waters. Three analytical techniques and several preservation methods were employed. Measurements of selenium speciation over time indicated that for accurate selenium speciation, it is best to conduct measurements on unpreserved, filtered samples as soon after sampling as possible. The capital and operating costs for two selenium management strategies were considered: ferric chloride addition and oxidation air flow rate control. For ferric chloride addition, as migh

Searcy, K.; Richardson, M.; Blythe, G.; Wallschlaeger, D.; Chu, P.; Dene, C.

2012-02-29T23:59:59.000Z

65

Development and Characterization of a Thermodenuder for Aerosol Volatility Measurements  

SciTech Connect

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

66

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

SciTech Connect

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

67

Quantification, Localization, and Speciation of Selenium in Seeds of Canola and Two Mustard Species Compared to Seed-Meals Produced  

E-Print Network (OSTI)

Quantification, Localization, and Speciation of Selenium in Seeds of Canola and Two Mustard Species with Se. We report a chemical analysis of Se in Brassica seeds (canola, Indian mustard, and white mustard shoots of several Brassica species, canola (Brassica napus), Indian mustard (Brassica juncea), and white

68

Mathematical modeling of the effects of aerobic and anaerobic chelate bioegradation on actinide speciation.  

SciTech Connect

Biodegradation of natural and anthropogenic chelating agents directly and indirectly affects the speciation, and, hence, the mobility of actinides in subsurface environments. We combined mathematical modeling with laboratory experimentation to investigate the effects of aerobic and anaerobic chelate biodegradation on actinide [Np(IV/V), Pu(IV)] speciation. Under aerobic conditions, nitrilotriacetic acid (NTA) biodegradation rates were strongly influenced by the actinide concentration. Actinide-chelate complexation reduced the relative abundance of available growth substrate in solution and actinide species present or released during chelate degradation were toxic to the organisms. Aerobic bio-utilization of the chelates as electron-donor substrates directly affected actinide speciation by releasing the radionuclides from complexed form into solution, where their fate was controlled by inorganic ligands in the system. Actinide speciation was also indirectly affected by pH changes caused by organic biodegradation. The two concurrent processes of organic biodegradation and actinide aqueous chemistry were accurately linked and described using CCBATCH, a computer model developed at Northwestern University to investigate the dynamics of coupled biological and chemical reactions in mixed waste subsurface environments. CCBATCH was then used to simulate the fate of Np during anaerobic citrate biodegradation. The modeling studies suggested that, under some conditions, chelate degradation can increase Np(IV) solubility due to carbonate complexation in closed aqueous systems.

Banaszak, J.E.; VanBriesen, J.; Rittmann, B.E.; Reed, D.T.

1998-03-19T23:59:59.000Z

69

Chemical Imaging Analysis of Environmental Particles Using the Focused Ion Beam/Scanning Electron Microscopy Technique: Microanalysis Insights into Atmospheric Chemistry of Fly Ash  

SciTech Connect

Airborne fly ash from coal combustion may represent a source of bioavailable iron (Fe) in the open ocean. However, few studies have been made focusing on Fe speciation and distribution in coal fly ash. In this study, chemical imaging of fly ash has been performed using a dual-beam FIB/SEM (focused ion beam/scanning electron microscope) system for a better understanding of how simulated atmospheric processing modify the morphology, chemical compositions and element distributions of individual particles. A novel approach has been applied for cross-sectioning of fly ash specimen with a FIB in order to explore element distribution within the interior of individual particles. Our results indicate that simulated atmospheric processing causes disintegration of aluminosilicate glass, a dominant material in fly ash particles. Aluminosilicate-phase Fe in the inner core of fly ash particles is more easily mobilized compared with oxide-phase Fe present as surface aggregates on fly ash spheres. Fe release behavior depends strongly on Fe speciation in aerosol particles. The approach for preparation of cross-sectioned specimen described here opens new opportunities for particle microanalysis, particular with respect to inorganic refractive materials like fly ash and mineral dust.

Chen, Haihan; Grassian, Vicki H.; Saraf, Laxmikant V.; Laskin, Alexander

2013-01-21T23:59:59.000Z

70

Linking color polymorphism maintenance and speciation  

E-Print Network (OSTI)

review the literatures of these two fields, seeking in particular to identify insights arising from, WI 53190, USA Here, we review the recently burgeoning literature on color polymorphisms, seeking: the study of the processes maintaining genetic variation in nature and the study of speciation. Here we

71

ARM - Measurement - Aerosol absorption  

NLE Websites -- All DOE Office Websites (Extended Search)

absorption absorption ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Aerosol absorption The process in which radiation energy is retained by aerosols. Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments AOS : Aerosol Observing System CSPHOT : Cimel Sunphotometer IAP : In-situ Aerosol Profiles (Cessna Aerosol Flights) PSAP : Particle Soot Absorption Photometer PASS : Photoacoustic Soot Spectrometer External Instruments OMI : Ozone Monitoring Instrument

72

ARM - Measurement - Aerosol concentration  

NLE Websites -- All DOE Office Websites (Extended Search)

concentration concentration ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Aerosol concentration A measure of the amount of aerosol particles (e.g. number, mass, volume) per unit volume of air. Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments AOS : Aerosol Observing System CSPHOT : Cimel Sunphotometer CPC : Condensation Particle Counter IAP : In-situ Aerosol Profiles (Cessna Aerosol Flights) TDMA : Tandem Differential Mobility Analyzer

73

Carbonaceous Aerosols and Radiative...  

NLE Websites -- All DOE Office Websites (Extended Search)

and absorption of light by aerosols. At the ground sites, a new Humidigraph, a Cloud Condensation Nuclei Counter, a Scanning Mobility Particle Sizer, and an upgraded 915-MHz...

74

Arsenic speciation in multiple metal environments: II. Micro-spectroscopic investigation of a CCA contaminated soil  

Science Journals Connector (OSTI)

The speciation of arsenic (As) in a copper-chromated-arsenate (CCA) contaminated soil was investigated using micro-focused X-ray fluorescence ( ? XRF ) and micro-focused X-ray absorption fine structure ( ? XAFS ) spectroscopies to determine if and how the co-contaminating metal cations (Cu, Zn, Cr) influenced the speciation of As. 15 ? XRF images were collected on 30-?m polished thin sections and powder-on-tape samples from which Pearson correlation coefficients ( ? ) between As and various metal species were determined based on the fluorescence intensity of each element in each image pixel. 29 ? XAFS and two bulk-XAFS spectra were collected from depths of 0–20 cm (LM-A) and 20–40 cm (LM-B) to determine the chemical speciation of As in the soil by target analyses of principal components with circa 52 reference spectra and linear least-square combination fitting of individual experimental spectra with a refined reference phase list (32) of likely As species. Arsenic and metal cations (Cr, Mn, Fe, Cu, Zn) accumulated in distinct, isolated areas often not larger than 50 × 50 ?m in which the Pearson correlation between the elements was strongly positive ( ? > 0.75 ) . The correlation of As to Zn and Cr decreased from >0.9 to 0.8 with depth. Arsenic occurred predominantly in the +5 oxidation state. Abstract factor analysis and linear least square combination fit analysis suggested that As occurred as a continuum of fully and poorly-ordered copper-arsenate precipitates with additional components being characterized by surface adsorption complexes on goethite and gibbsite in the presence and absence of Zn. Precipitates other than copper-based ones, e.g., scorodite, adamite and ojuelaite were also identified. The significant co-localization and chemical speciation of As with Cu suggest that the speciation of As in a contaminated soils is not solely controlled by surface adsorption reactions, but significantly influenced by the co-contaminating metal cation fraction. Future studies into As contaminated soil therefore need to focus on identifying the speciation of As and the co-localizing metal cations.

Markus Gräfe; Ryan V. Tappero; Matthew A. Marcus; Donald L. Sparks

2008-01-01T23:59:59.000Z

75

Direct Aerosol Forcing Uncertainty  

DOE Data Explorer (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

76

BNL | Aerosol Lifecycle IOP  

NLE Websites -- All DOE Office Websites (Extended Search)

Program Program Aerosol Life Cycle IOP The primary objectives that make up the Aerosol Life Cycle IOP can be broken down into three categories: Scientific; Logistical; and GVAX preparation. Scientific Objectives The science goals are to conduct intensive aerosol observations in a region exposed to anthropogenic, biogenic, and marine emissions with atmospheric processing times depending on air mass trajectories and time of day. Take advantage of new instruments in the MAOS (e.g., SP2, HR-PTRMS, ACSM, Trace Gas Suite, PASS-3, Aethelometer, UHSAS). Within this broad umbrella are embedded three main foci: Aerosol light absorption: How does the aerosol mass absorption coefficient (absorption per unit mass of BC) vary with atmospheric processing? Do observations agree with a shell-core model?

77

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

78

Metal Speciation in Landfill Leachates with a Focus on the Influence of Organic Matter  

SciTech Connect

This study characterizes the heavy-metal content in leachates collected from eight landfills in France. In order to identify heavy metal occurrence in the different size fractions of leachates, a cascade filtration protocol was applied directly in the field, under a nitrogen gas atmosphere to avoid metal oxidation. The results of analyses performed on the leachates suggest that most of the metals are concentrated in the <30 kDa fraction, while lead, copper and cadmium show an association with larger particles. Initial speciation calculations, without considering metal association with organic matter, suggest that leachate concentrations in lead, copper, nickel and zinc are super-saturated with respect to sulphur phases. Speciation calculations that account for metal complexation with organic matter, considered as fulvic acids based on C1(s) NEXAFS spectroscopy, show that this mechanism is not sufficient to explain such deviation from equilibrium conditions. It is therefore hypothesized that the deviation results also from the influence of biological activity on the kinetics of mineral phase precipitation and dissolution, thus providing a dynamic system. The results of chemical analyses of sampled fluids are compared with speciation calculations and some implications for the assessment of metal mobility and natural attenuation in a context of landfill risk assessment are discussed.

F Claret; C Tournassat; C Crouzet; E Gaucher; T Schäfer; G Braibant; D Guyonnet

2011-12-31T23:59:59.000Z

79

ARM - Measurement - Aerosol particle size  

NLE Websites -- All DOE Office Websites (Extended Search)

particle size particle size ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Aerosol particle size Linear size (e.g. radius or diameter) of an aerosol particle. Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. Field Campaign Instruments AEROSMASSSPEC : Aerosol Mass Spectrometer CPI : Cloud Particle Imager DRI-GND : Desert Research Institute Ground-Based Aerosol Instruments DRUM-AEROSOL : Drum Aerosol Sampler AEROSOL-TOWER-EML : EML Tower based Aerosol Measurements

80

Tropospheric Reactive Nitrogen Speciation, Deposition, and Chemistry at Harvard Forest  

E-Print Network (OSTI)

and absolute contributions of nitric acid (HNO3) and NOx (nitric oxide (NO) + nitrogen dioxide (NO2)) to totalTropospheric Reactive Nitrogen Speciation, Deposition, and Chemistry at Harvard Forest A thesis. Steven C. Wofsy Cassandra Volpe Horii Tropospheric Reactive Nitrogen Speciation, Deposition

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

How Physical and Chemical Properties Change Ice Nucleation Efficiency of Soot and Polyaromatic Hydrocarbon Particles  

E-Print Network (OSTI)

of laboratory experiments using an optical microscope apparatus equipped with a cooling stage to determine how chemical oxidation changes the ability of atmospheric aerosols to act as IN. Freezing temperatures are reported for aerosols composed of fresh...

Suter, Katie Ann

2012-10-19T23:59:59.000Z

82

A World-wide Stratospheric Aerosol Layer  

Science Journals Connector (OSTI)

...Massachusetts An aerosol layer has been identified by a stratospheric balloon and aircraft aerosol collection program. Measurements...Abstract. An aerosol layer has been identified by a stratospheric balloon and aircraft aerosol collection program. Meas-urements...

Christian E. Junge; Charles W. Chagnon; James E. Manson

1961-05-12T23:59:59.000Z

83

PILOT-SCALE EVALUATION OF THE IMPACT OF SELECTIVE CATALYTIC REDUCTION FOR NOx ON MERCURY SPECIATION  

SciTech Connect

Full-scale tests in Europe and bench-scale tests in the United States have indicated that the catalyst, normally vanadium/titanium metal oxide, used in the selective catalytic reduction (SCR) of NO{sub x}, may promote the formation of Hg{sup 2+} and/or particulate-bound mercury (Hg{sub p}). To investigate the impact of SCR on mercury speciation, pilot-scale screening tests were conducted at the Energy & Environmental Research Center. The primary research goal was to determine whether the catalyst or the injection of ammonia in a representative SCR system promotes the conversion of Hg{sup 0} to Hg{sup 2+} and/or Hg{sub p} and, if so, which coal types and parameters (e.g., rank and chemical composition) affect the degree of conversion. Four different coals, three eastern bituminous coals and a Powder River Basin (PRB) subbituminous coal, were tested. Three tests were conducted for each coal: (1) baseline, (2) NH{sub 3} injection, and (3) SCR of NO{sub x}. Speciated mercury, ammonia slip, SO{sub 3}, and chloride measurements were made to determine the effect the SCR reactor had on mercury speciation. It appears that the impact of SCR of NO{sub x} on mercury speciation is coal-dependent. Although there were several confounding factors such as temperature and ammonia concentrations in the flue gas, two of the eastern bituminous coals showed substantial increases in Hg{sub p} at the inlet to the ESP after passing through an SCR reactor. The PRB coal showed little if any change due to the presence of the SCR. Apparently, the effects of the SCR reactor are related to the chloride, sulfur and, possibly, the calcium content of the coal. It is clear that additional work needs to be done at the full-scale level.

Dennis L. Laudal; John H. Pavlish; Kevin C. Galbreath; Jeffrey S. Thompson; Gregory F. Weber; Everett Sondreal

2000-12-01T23:59:59.000Z

84

Thermally Speciated Mercury in Mineral Exploration | Open Energy  

Open Energy Info (EERE)

Thermally Speciated Mercury in Mineral Exploration Thermally Speciated Mercury in Mineral Exploration Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper: Thermally Speciated Mercury in Mineral Exploration Abstract Abstract unavailable. Author S.C. Smith Conference IGES; Dublin, CA; 2003/09/01 Published IGES, 2003 DOI Not Provided Check for DOI availability: http://crossref.org Citation S.C. Smith. 2003. Thermally Speciated Mercury in Mineral Exploration. In: Programs & Abstracts: Soil and Regolith Geochemistry in the Search for Mineral Deposits. IGES; 2003/09/01; Dublin, CA. Dublin, CA: IGES; p. 78 Retrieved from "http://en.openei.org/w/index.php?title=Thermally_Speciated_Mercury_in_Mineral_Exploration&oldid=681717" Categories: References Geothermal References

85

Direct and semi-direct radiative effects of anthropogenic aerosols in the Western United States: Seasonal  

E-Print Network (OSTI)

a regional climate model (RCM) in conjunction with the aerosol fields from a GEOS-Chem chemical- transport emissions and the seasonal low-level winds. The RCM-simulated anthropogenic aerosol radiative effects vary, respectively, following the seasonal AOD. In Arizona-New Mexico (AZNM), the effect of anthropogenic sulfates

Liou, K. N.

86

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

SciTech Connect

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

87

A two-dimensional volatility basis set – Part 2: Diagnostics of organic-aerosol evolution  

E-Print Network (OSTI)

We discuss the use of a two-dimensional volatility-oxidation space (2-D-VBS) to describe organic-aerosol chemical evolution. The space is built around two coordinates, volatility and the degree of oxidation, both of which ...

Donahue, N. M.

88

Priorities for In-situ Aerosol Measurements  

NLE Websites -- All DOE Office Websites (Extended Search)

Priorities for In-situ Priorities for In-situ Aerosol Measurements Parameters * Aerosol light absorption coefficient - spectral, including UV, vis, and IR - as f(RH), and at ambient RH * Phase function - or relevant integral properties (how many?) * Ice nuclei * Scattering vs. RH, for RH>90% * CCN, as f(S, D p ) * Size distribution * Chemical composition - for determining climate forcing, vs. radiative effect Calibration * Number concentration * Size and shape * Light absorption reference method Characterization * Accuracy and precision - need well-understood error bars * Algorithm comparisons * Closure studies * Facilities for method testing - aircraft time Methods * Inlets - shattering/splashing - location on airplane - passing efficiency - inletless analyzers/samplers * Packaging - modular/portable "pods" for multiple a/c

89

Geometrical Optics of Dense Aerosols  

SciTech Connect

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

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

2013-04-24T23:59:59.000Z

90

BNL | Aerosol, Cloud, Precipitation Interactions  

NLE Websites -- All DOE Office Websites (Extended Search)

Cloud-Aerosol-Precipitation Interactions Cloud-Aerosol-Precipitation Interactions Atmospheric aerosols exert important "indirect effects" on clouds and climate by serving as cloud condensation nuclei (CCN) and ice nuclei that affect cloud radiative and microphysical properties. For example, an increase in CCN increases the number concentration of droplets enhances cloud albedo, and suppresses precipitation that alters cloud coverage and lifetime. However, in the case of moist and strong convective clouds, increasing aerosols may increase precipitation and enhance storm development. Although aerosol-induced indirect effects on climate are believed to have a significant impact on global climate change, estimating their impact continues to be one of the most uncertain climate forcings.

91

Jankovic Aerosol Characterization.ppt  

NLE Websites -- All DOE Office Websites (Extended Search)

Characterization, Characterization, Aerosol Characterization, Interpretation, and Interpretation, and Application of Data Application of Data NSRC Symposium NSRC Symposium July 8, 2008 John Jankovic, CIH CIH Center for Nanophase Materials Sciences Center for Nanophase Materials Sciences Aerosol Characterization, Interpretation, and Aerosol Characterization, Interpretation, and Application of Data Application of Data Department of Energy (DOE) Nanoscale Science Research Centers (NSRC) developing Approach to Nanomaterial ES&H - The CNMS Approach * Establish Exposure Control Guideline (ECG) - Characterize Aerosol * Collect and interpret data * Assign Process to a Control Band Aerosol Particle Characterization * Size distribution (geometric mean and geometric standard deviation related to either mass, surface, or number)

92

Strontium Speciation during Reaction of Kaolinite with Simulated  

E-Print Network (OSTI)

Strontium Speciation during Reaction of Kaolinite with Simulated Tank-Waste Leachate: Bulk, Arizona 85721 Radioactive strontium (90Sr) is an important constituent of the complex wastes from past

Chorover, Jon

93

Genetic architecture and ecological speciation in Heliconius butterflies  

E-Print Network (OSTI)

forms (LEMMON and LEMMON 2010; NAISBIT et al. 2001; SVEDIN et al. 2008). Box 2. Secondary contact and reinforcement-like mechanisms During sympatric speciation mating traits may diverge in a process analogous to ‘reinforcement’ (and is in fact... forms (LEMMON and LEMMON 2010; NAISBIT et al. 2001; SVEDIN et al. 2008). Box 2. Secondary contact and reinforcement-like mechanisms During sympatric speciation mating traits may diverge in a process analogous to ‘reinforcement’ (and is in fact...

Merrill, Richard

2013-04-28T23:59:59.000Z

94

Aerosols in a Changing Atmosphere: From Detailed Aerosol Microphysics to  

NLE Websites -- All DOE Office Websites (Extended Search)

Aerosols in a Changing Atmosphere: From Detailed Aerosol Microphysics to Aerosols in a Changing Atmosphere: From Detailed Aerosol Microphysics to Policy Applications Speaker(s): Susanne Bauer Date: December 6, 2011 - 4:00pm Location: 90-4133 Seminar Host/Point of Contact: Surabi Menon The anthropogenic increase in aerosol concentrations since preindustrial times and its net cooling effect on the atmosphere is thought to mask some of the greenhouse gas induced warming. Although the overall effect of aerosols on solar radiation and clouds is most certainly negative, some individual forcing agents and feedbacks have positive forcing effects. Recent studies have tried to identify some of those positive forcing agents and their individual emission sectors, However, understanding the net effect of multi-source emitting sectors and the involved cloud feedbacks is

95

Sulfate aerosols and polar stratospheric cloud formation  

SciTech Connect

Before the discovery of the Antarctic ozone hole, it was generally assumed that gas-phase chemical reactions controlled the abundance of stratospheric ozone. However, the massive springtime ozone losses over Antarctica first reported by Farman et al in 1985 could not be explained on the basis of gas-phase chemistry alone. In 1986, Solomon et al suggested that chemical reactions occurring on the surfaces of polar stratospheric clouds (PSCs) could be important for the observed ozone losses. Since that time, an explosion of laboratory, field, and theoretical research in heterogeneous atmospheric chemistry has occurred. Recent work has indicated that the most important heterogeneous reaction on PSCs is ClONO[sub 2] + HCl [yields] Cl[sub 2] + HNO[sub 3]. This reaction converts inert chlorine into photochemically active Cl[sub 2]. Photolysis of Cl[sub 2] then leads to chlorine radicals capable of destroying ozone through very efficient catalytic chain reactions. New observations during the second Airborne Arctic Stratospheric Expedition found stoichiometric loss of ClONO[sub 2] and HCl in air processed by PSCs in accordance with reaction 1. Attention is turning toward understanding what kinds of aerosols form in the stratospheric, their formation mechanism, surface area, and specific chemical reactivity. Some of the latest findings, which underline the importance of aerosols, were presented at a recent National Aeronautics and Space Administration workshop in Boulder, Colorado.

Tolbert, M.A. (Univ. of Colorado, Boulder, CO (United States))

1994-04-22T23:59:59.000Z

96

Evolution of Asian aerosols during transpacific transport in INTEX-B  

SciTech Connect

Measurements of aerosol composition were made with an Aerodyne High Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) on board the NSF/NCAR C-130 aircraft as part of the Intercontinental Chemical Transport Experiment Phase B 5 (INTEX-B) field campaign over the Eastern Pacific Ocean. The HR-ToF-AMS measurements of non-refractory submicron aerosol mass are shown to compare well with other aerosol instrumentation in the INTEX-B field study. Two case studies are described for pollution layers transported across the Pacific from the Asian continent, intercepted 3–4 days and 7–10 days downwind of Asia, respectively. Aerosol chemistry is shown to 10 be a robust tracer for air masses originating in Asia, specifically the presence of sulfate dominated aerosol is a distinguishing feature of Asian pollution layers that have been transported to the Eastern Pacific. We examine the time scales of processing for sulfate and organic aerosol in the atmosphere and show that our observations confirm a conceptual model for transpacific transport from Asia proposed by Brock et al. (2004). 15 Our observations of both sulfate and organic aerosol in aged Asian pollution layers are consistent with fast formation near the Asian continent, followed by washout during lofting and subsequent transformation during transport across the Pacific. Our observations are the first atmospheric measurements to indicate that although secondary organic aerosol (SOA) formation from pollution happens on the timescale of one day, 20 the oxidation of organic aerosol continues at longer timescales in the atmosphere. Comparisons with chemical transport models of data from the entire campaign reveal an under-prediction of SOA mass in the MOZART model, but much smaller discrepancies with the GEOS-Chem model than found in previous studies over the Western Pacific. No evidence is found to support a previous hypothesis for significant secondary 25 organic aerosol formation in the free troposphere.

Dunlea, E. J.; DeCarlo, Peter; Aiken, Allison; Kimmel, Joel; Peltier, R. E.; Weber, R. J.; Tomlinson, Jason M.; Collins, Donald R.; Shinozuka, Yohei; McNaughton, C. S.; Howell, S. G.; Clarke, A. D.; Emmons, L.; Apel, Eric; Pfister, G. G.; van Donkelaar, A.; Martin, R. V.; Millet, D. B.; Heald, C. L.; Jimenez, J. L.

2009-10-01T23:59:59.000Z

97

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

98

ARM - Mobile Aerosol Observing System  

NLE Websites -- All DOE Office Websites (Extended Search)

FacilitiesMobile Aerosol Observing System FacilitiesMobile Aerosol Observing System AMF Information Science Architecture Baseline Instruments AMF1 AMF2 AMF3 Data Operations AMF Fact Sheet Images Contacts AMF Deployments Hyytiälä, Finland, 2014 Manacapuru, Brazil, 2014 Oliktok Point, Alaska, 2013 Los Angeles, California, to Honolulu, Hawaii, 2012 Cape Cod, Massachusetts, 2012 Gan Island, Maldives, 2011 Ganges Valley, India, 2011 Steamboat Springs, Colorado, 2010 Graciosa Island, Azores, 2009-2010 Shouxian, China, 2008 Black Forest, Germany, 2007 Niamey, Niger, 2006 Point Reyes, California, 2005 Mobile Aerosol Observing System Intensive aerosol observations conducted on the campus of Brookhaven National Laboratory on Long Island, New York, using the ARM Mobile Aerosol Observing System. Intensive aerosol observations conducted on the campus of Brookhaven

99

Aerosol Observing System (AOS) Handbook  

SciTech Connect

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

Jefferson, A

2011-01-17T23:59:59.000Z

100

Metal speciation in landfill leachates with a focus on the influence of organic matter  

SciTech Connect

Highlights: > This study characterises the heavy-metal content in leachates collected from eight landfills in France. > Most of the metals are concentrated in the <30 kDa fraction, while Pb, Cu and Cd are associated with larger particles. > Metal complexation with OM is not sufficient to explain apparent supersaturation of metals with sulphide minerals. - Abstract: This study characterises the heavy-metal content in leachates collected from eight landfills in France. In order to identify heavy metal occurrence in the different size fractions of leachates, a cascade filtration protocol was applied directly in the field, under a nitrogen gas atmosphere to avoid metal oxidation. The results of analyses performed on the leachates suggest that most of the metals are concentrated in the <30 kDa fraction, while lead, copper and cadmium show an association with larger particles. Initial speciation calculations, without considering metal association with organic matter, suggest that leachate concentrations in lead, copper, nickel and zinc are super-saturated with respect to sulphur phases. Speciation calculations that account for metal complexation with organic matter, considered as fulvic acids based on C1(s) NEXAFS spectroscopy, show that this mechanism is not sufficient to explain such deviation from equilibrium conditions. It is therefore hypothesized that the deviation results also from the influence of biological activity on the kinetics of mineral phase precipitation and dissolution, thus providing a dynamic system. The results of chemical analyses of sampled fluids are compared with speciation calculations and some implications for the assessment of metal mobility and natural attenuation in a context of landfill risk assessment are discussed.

Claret, Francis, E-mail: f.claret@brgm.fr [BRGM, 3 avenue C. Guillemin, BP 6009, 45060 Orleans (France); Tournassat, Christophe; Crouzet, Catherine; Gaucher, Eric C. [BRGM, 3 avenue C. Guillemin, BP 6009, 45060 Orleans (France); Schaefer, Thorsten [Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), P.O. Box 3640, 76021 Karlsruhe (Germany); Freie Universitaet Berlin, Institute of Geological Sciences, Department of Earth Sciences, Hydrogeology Group, D-12249 Berlin (Germany); Braibant, Gilles; Guyonnet, Dominique [BRGM, 3 avenue C. Guillemin, BP 6009, 45060 Orleans (France)

2011-09-15T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

Flattening coefficient of aerosols collected on treated slides  

E-Print Network (OSTI)

collected from oleic acid and DOP (dioctylphthalate) aerosols, The microscope slides were made oilphobic by immersion in a widely used fluorocarbon sur- factant (NYE BAR Type CT 2X or 3' Co. Chemical FC-721). The mean value of F f' or oleic acid... was found to be 1. 338, and for DOP, 1. 354. There is no apparent variation of F with particle diameter for aerosols in the 2. 7-29. 1 um range. The slightly lower value of F for oleic acid suggests that the contact angle of oleic acid with respect...

Olan-Figueroa, Excel

2012-06-07T23:59:59.000Z

102

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

103

EMSL: Science: Atmospheric Aerosol Systems  

NLE Websites -- All DOE Office Websites (Extended Search)

Atmospheric Aerosol Systems Atmospheric Aerosol Systems atmospheric logo Nighttime enhancement of nitrogen-containing organic compounds, or NOC Observed nighttime enhancement of nitrogen-containing organic compounds, or NOC, showed evidence of being formed by reactions that transform carbonyls into imines. The Atmospheric Aerosol Systems Science Theme focuses on understanding the chemistry, physics and molecular-scale dynamics of aerosols for model parameterization to improve the accuracy of climate model simulations and develop a predictive understanding of climate. By elucidating the role of natural and anthropogenic regional and global climate forcing mechanisms, EMSL can provide DOE and others with the ability to develop cost-effective strategies to monitor, control and mitigate them.

104

Two-Column Aerosol Project  

NLE Websites -- All DOE Office Websites (Extended Search)

help find the answer, the Department of Energy's Atmospheric Radiation Measurement (ARM) Climate Research Facility is conducting the Two-Column Aerosol Project (TCAP) at Cape Cod...

105

ARM Cloud Aerosol Precipitation Experiment  

NLE Websites -- All DOE Office Websites (Extended Search)

Satellite Observation CAS Cloud Aerosol Spectrometer CCN Cloud Condensation Nuclei CIP Cloud Imaging Probe CPC Condensation Particle Counter CSPHOT Cimel sunphotometer CVI...

106

Direct Aerosol Forcing in the Infrared at the SGP Site?  

NLE Websites -- All DOE Office Websites (Extended Search)

Direct Aerosol Forcing in the Infrared at the SGP Site? Direct Aerosol Forcing in the Infrared at the SGP Site? D. D. Turner and C. N. Long Pacific Northwest National Laboratory Richland, Washington Introduction Low level haze is often observed during the night and early morning hours in many locations. This haze is typically formed during quiescent conditions by radiative cooling of the surface, which lowers the ambient temperature and consequently increases the near-surface relative humidity (RH). Many aerosols start to deliquesce around 75% relative humidity (RH) (depending on their chemical composition), and thus if the near surface RH increases above this level, haze will form. The Atmospheric Radiation Measurement (ARM) Program's ultimate goal, stated simply, is to improve the treatment of radiative transfer in global climate models. Global climate models typically do not

107

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

108

Ganges Valley Aerosol Experiment: Science and Operations Plan  

SciTech Connect

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

109

Aerosol Data Sources and Their Roles within PARAGON  

SciTech Connect

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

110

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

SciTech Connect

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

111

4, 58315854, 2004 Fluorescing aerosol  

E-Print Network (OSTI)

released by combustion into the atmosphere absorbs radiation and therefore heats the climate counteracting such as polycyclic aromatic hydrocarbons sticking to the aerosol particles, or bioaerosol such as bacteria, spores) or by combustion processes (soot), or they form in situ by gas to particle conversion, like sulphate aerosol. While

Paris-Sud XI, Université de

112

Uranium speciation in glass corrosion layers: An XAFS study  

SciTech Connect

Uranium L{sub 3} X-ray absorption data were obtained from two borosilicate glasses, which are considered as models for radioactive wasteforms, both before and after leaching. Surface sensitivity to uranium speciation was attained by a novel application of simultaneous fluorescence and electron-yield detection. Changes in speciation are clearly discernible, from U(VI) in the bulk to (UO{sub 2}){sup 2+}-uranyl in the corrosion layer. The uranium concentrations within the corrosion layer also show variations with leaching times that can be determined from the data.

Biwer, B.M.; Soderholm, L. [Argonne National Lab., IL (United States); Greegor, R.B. [Boeing Co., Seattle, WA (United States); Lytle, F.W. [EXAFS Co., Pioche, NV (United States)

1997-12-31T23:59:59.000Z

113

XANES Identification of Plutonium Speciation in RFETS Samples  

SciTech Connect

Using primarily X-ray absorption near edge spectroscopy (XANES) with standards run in tandem with samples, probable plutonium speciation was determined for 13 samples from contaminated soil, acid-splash or fire-deposition building interior surfaces, or asphalt pads from the Rocky Flats Environmental Technology Site (RFETS). Save for extreme oxidizing situations, all other samples were found to be of Pu(IV) speciation, supporting the supposition that such contamination is less likely to show mobility off site. EXAFS analysis conducted on two of the 13 samples supported the validity of the XANES features employed as determinants of the plutonium valence.

LoPresti, V.; Conradson, S.D.; Clark, D.L.

2009-06-03T23:59:59.000Z

114

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

115

Aerosol Laboratory - Nuclear Engineering Division (Argonne)  

NLE Websites -- All DOE Office Websites (Extended Search)

Capabilities > Engineering Capabilities > Engineering Experimentation > Aerosol Laboratory Capabilities Engineering Experimentation Reactor Safety Experimentation Aerosol Experiments System Components Laser Applications Robots Applications Other Facilities Other Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Aerosol Laboratory The Aerosol Laboratory (AL) houses equipment to measure and record the physical parameters necessary to characterize the formation and transport of aerosols. Bookmark and Share The Aerosol Laboratory (AL) has extensive analytic and experimental capabilities to characterize the formation and transport of aerosols formed from the condensation of vapors. Computer codes have been developed to

116

DEVELOPMENT OF FINE PARTICULATE EMISSION FACTORS AND SPECIATION PROFILES FOR OIL AND GAS FIRED COMBUSTION SYSTEMS  

SciTech Connect

This report provides results from the second year of this three-year project to develop dilution measurement technology for characterizing PM2.5 (particles with aerodynamic diameter smaller than 2.5 micrometers) and precursor emissions from stationary combustion sources used in oil, gas and power generation operation. Detailed emission rate and chemical speciation tests results for a gas turbine, a process heater, and a commercial oil/gas fired boiler are presented. Tests were performed using a research dilution sampling apparatus and traditional EPA methods. A series of pilot tests were conducted to identify the constraints to reduce the size of current research dilution sampler for future stack emission tests. Based on the test results, a bench prototype compact dilution sampler developed and characterized in GE EER in August 2002.

Glenn England; Oliver Chang; Stephanie Wien

2002-02-14T23:59:59.000Z

117

Chapter Thirteen - Speciation Genomics of Fungal Plant Pathogens  

Science Journals Connector (OSTI)

Abstract Fungi have relatively small genomes, and many species are amendable to experimental and molecular manipulation making them excellent models to unravel the genetic, molecular and cellular aspects of speciation. Pioneering work has been conducted in the two model species Saccharomyces cerevisiae and Neurospora crassa where integrated studies using classical genetics, genomic resources and experimental approaches have shed light on mechanisms conferring reproductive isolation between diverged lineages. Experimental evolution, genetic mapping and molecular manipulation can be considerably more challenging in species of fungal plant pathogens. Yet, insight into speciation genetics is fundamental to understand the emergence of new pathogen species. Now, several fundamental questions relating to speciation genetics can be addressed using the growing resource of genome data. Population genomics and comparative genomics approaches offer the possibility of not only recapturing the evolutionary history of species but also identifying signatures of selection and genomic rearrangements associated with speciation events. Thereby, both the history of species and the underlying genetics associated with the establishment of reproductive isolation can be recovered.

Eva H. Stukenbrock

2014-01-01T23:59:59.000Z

118

Glutamate Surface Speciation on Amorphous Titanium Dioxide and  

E-Print Network (OSTI)

Glutamate Surface Speciation on Amorphous Titanium Dioxide and Hydrous Ferric Oxide D I M I T R I (HFO) and titanium dioxide exhibit similar strong attachment of many adsorbates including biomolecules on amorphous titanium dioxide. The results indicate that glutamate adsorbs on HFO as a deprotonated divalent

Sverjensky, Dimitri A.

119

ARM - Surface Aerosol Observing System  

NLE Websites -- All DOE Office Websites (Extended Search)

FacilitiesSurface Aerosol Observing System FacilitiesSurface Aerosol Observing System AMF Information Science Architecture Baseline Instruments AMF1 AMF2 AMF3 Data Operations AMF Fact Sheet Images Contacts AMF Deployments Hyytiälä, Finland, 2014 Manacapuru, Brazil, 2014 Oliktok Point, Alaska, 2013 Los Angeles, California, to Honolulu, Hawaii, 2012 Cape Cod, Massachusetts, 2012 Gan Island, Maldives, 2011 Ganges Valley, India, 2011 Steamboat Springs, Colorado, 2010 Graciosa Island, Azores, 2009-2010 Shouxian, China, 2008 Black Forest, Germany, 2007 Niamey, Niger, 2006 Point Reyes, California, 2005 Surface Aerosol Observing System The ARM Mobile Facility (AMF) is equipped to quantify the interaction between clouds and aerosol particles. A counter-flow virtual impactor (CVI) is used to selectively sample cloud drops. The CVI takes advantage of the

120

Factors affecting the indoor concentrations of carbonaceous aerosols of outdoor origin  

SciTech Connect

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

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

Aerodyne Develops an Aircraft-Deployable Precision Aerosol Analyzer | U.S.  

Office of Science (SC) Website

Aerodyne Develops an Aircraft-Deployable Precision Aerosol Aerodyne Develops an Aircraft-Deployable Precision Aerosol Analyzer Small Business Innovation Research (SBIR) and Small Business Technology Transfer (STTR) SBIR/STTR Home About Funding Opportunity Announcements (FOAs) Applicant and Awardee Resources Commercialization Assistance Other Resources Awards SBIR/STTR Highlights Reporting Fraud Contact Information Small Business Innovation Research and Small Business Technology Transfer U.S. Department of Energy SC-29/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-5707 F: (301) 903-5488 E: sbir-sttr@science.doe.gov More Information » January 2013 Aerodyne Develops an Aircraft-Deployable Precision Aerosol Analyzer Aerodyne Research Inc. develops an aerosol mass spectrometer (AMS) that fills a critical need for size-resolved, quantitative chemical composition

122

Aerosol Resuspension Model for MELCOR for Fusion and Very High Temperature Reactor Applications  

SciTech Connect

Dust is generated in fusion reactors from plasma erosion of plasma facing components within the reactor’s vacuum vessel (VV) during reactor operation. This dust collects in cooler regions on interior surfaces of the VV. Because this dust can be radioactive, toxic, and/or chemically reactive, it poses a safety concern, especially if mobilized by the process of resuspension during an accident and then transported as an aerosol though out the reactor confinement building, and possibly released to the environment. A computer code used at the Idaho National Laboratory (INL) to model aerosol transport for safety consequence analysis is the MELCOR code. A primary reason for selecting MELCOR for this application is its aerosol transport capabilities. The INL Fusion Safety Program (FSP) organization has made fusion specific modifications to MELCOR. Recent modifications include the implementation of aerosol resuspension models in MELCOR 1.8.5 for Fusion. This paper presents the resuspension models adopted and the initial benchmarking of these models.

B.J. Merrill

2011-01-01T23:59:59.000Z

123

Conclusions of the Capstone Depleted Uranium Aerosol Characterization and Risk Assessment Study  

SciTech Connect

The rationale for the Capstone Depleted Uranium (DU) Aerosol Characterization and Risk Assessment Program and its results and applications have been examined in the previous 13 articles of this special issue. This paper summarizes the results and discusses its successes and lessons learned. The robust data from the Capstone DU Aerosol Study have provided a sound basis for assessing the inhalation exposure to DU aerosols and the dose and risk to personnel in combat vehicles at the time of perforation and to those entering immediately after perforation. The Human Health Risk Assessment provided a technically sound process for evaluating chemical and radiological doses and risks from DU aerosol exposure using well-accepted biokinetic and dosimetric models innovatively applied. An independent review of the study process and results is summarized, and recommendations for possible avenues of future study by the authors and by other major reviews of DU health hazards are provided.

Parkhurst, MaryAnn; Guilmette, Raymond A.

2009-02-26T23:59:59.000Z

124

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

125

Geological and Anthropogenic Factors Influencing Mercury Speciation in Mine  

NLE Websites -- All DOE Office Websites (Extended Search)

Geological and Anthropogenic Factors Influencing Mercury Speciation Geological and Anthropogenic Factors Influencing Mercury Speciation in Mine Wastes Christopher S. Kim,1 James J. Rytuba,2 Gordon E. Brown, Jr.3 1Department of Physical Sciences, Chapman University, Orange, CA 92866 2U.S. Geological Survey, Menlo Park, CA 94025 3Department of Geological and Environmental Sciences, Stanford University, Stanford, CA 94305 Introduction Figure 1. Dr. Christopher Kim collects a mine waste sample from the Oat Hill mercury mine in Northern California. The majority of mercury mine wastes at these sites are present as loose, unconsolidated piles, facilitating the transport of mercury-bearing material downstream into local watersheds. Mercury (Hg) is a naturally occurring element that poses considerable health risks to humans, primarily through the consumption of fish which

126

Speciation of uranium(VI) sorption complexes on montmorillonite  

SciTech Connect

Environmental contaminant releases that contain uranium are among the most serious problems that must be confronted by restoration programs. To facilitate restoration, information concerning the speciation of uranium is needed. Under oxidizing conditions, dissolved uranium is predominantly in the U(VI) (uranyl) form and is quite mobile in the environment, however sorption onto soils may retard its movement. In this study, we have investigated the effects of changes in solution speciation on the nature of uranyl sorption complexes on montmorillonite, a common soil constituent. Aqueous U(VI) solutions between pH 3 to 7 were batch-equilibrated with montmorillonite for several days; specific pH values were selected such that the solutions consisted of dominantly monomeric, oligomeric, or a mix of monomeric and oligomeric aqueous uranyl species. Emission spectroscopy was used to investigate the nature of U(VI) sorbed to montmorillonite.

Chisholm-Brause, C.J.; Morris, D.E. (Los Alamos National Lab., NM (United States)); Richard, R.E. (Fort Lewis Coll., Durango, CO (United States). Dept. of Chemistry)

1992-01-01T23:59:59.000Z

127

ARM - Evaluation Product - Organic Aerosol Component VAP  

NLE Websites -- All DOE Office Websites (Extended Search)

ProductsOrganic Aerosol Component VAP ProductsOrganic Aerosol Component VAP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : Organic Aerosol Component VAP 2011.01.08 - 2012.03.24 Site(s) SGP General Description Organic aerosol (OA, i.e., the organic fraction of particles) accounts for 10-90% of the fine aerosol mass globally and is a key determinant of aerosol radiative forcing. But atmospheric OA is poorly characterized and its life cycle insufficiently represented in models. As a result, current models are unable to simulate OA concentrations and properties. This deficiency represents a large source of uncertainty in the quantification of aerosol direct and indirect effects and the prediction of future climate change. The Organic Aerosol Component (OACOMP) value-added product (VAP) uses

128

ARM - Field Campaign - Fall 1997 Aerosol IOP  

NLE Websites -- All DOE Office Websites (Extended Search)

Aerosol IOP Aerosol IOP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Fall 1997 Aerosol IOP 1997.09.15 - 1997.10.05 Lead Scientist : Stephen Schwartz For data sets, see below. Summary The Aerosol IOP was highlighted by the Gulfstream-1 aircraft flying clear-sky aerosol missions over the Central Facility to study the effect of aerosol loading on clear sky radiation fields, with weather particularly favorable for these flights during the first and third weeks of the IOP. A secondary but important goal of this IOP was to fly cloudy-sky missions over the Central Facility to study the effect of aerosol loading on cloud microphysics, and the effect of the microphysics on cloud optical properties. The Gulfstream obtained aerosol data in support of some of the

129

Antiviral therapy with small particle aerosols  

Science Journals Connector (OSTI)

The generation and use of small particle aqueous aerosols (1.23 µm aerodynamic mass median diameter, GSD=2.0 µm) containing ribavirin is described. Administered via aerosol, ribavirin will be deposited rather ...

V. Knight; B. Gilbert

1988-12-01T23:59:59.000Z

130

E-Print Network 3.0 - airborne aerosol prediction Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

profiles of aerosol extinction and optical depth Evaluate predictions from aerosol transport... aerosol measurements. Comparison of AOT ... Source: Brookhaven National...

131

NETL: Utilization Projects - Speciation and Attenuation of Arsenic and  

NLE Websites -- All DOE Office Websites (Extended Search)

Speciation and Attenuation of Arsenic and Selenium at Coal Combustion By-Product Management Facilities Speciation and Attenuation of Arsenic and Selenium at Coal Combustion By-Product Management Facilities The overall objective of this project is to evaluate the impact of key constituents captured from power plant air streams (arsenic, selenium and mercury) on the disposal and utilization of coal combustion by-products. Specific objectives of the project are: 1) to develop a comprehensive database of field leachate concentrations at a wide range of CCB management sites (about 25 sites), including speciation of arsenic and selenium, and low-detection limit analyses for mercury; and 2) to perform detailed evaluations of the release and attenuation of arsenic and selenium species at 3 CCB sites. The fundamental or mechanistic data to reliably model many of the inorganics in CCB leachate are lacking. There is a large degree of uncertainty in the initial leachate concentrations, long-term leaching characteristics of CCBs, and the attenuation coefficients typically used in groundwater transport models. As a result, the model simulations are either highly conservative, or they can be manipulated to obtain almost any desired result. This research project will develop a coherent field leachate database and soil attenuation coefficients for improved modeling and evaluation of the potential for groundwater impacts at CCB management facilities. The work is focused on speciation of four key constituents at CCB sites: arsenic, selenium, chromium, and mercury. The proposed work will help to narrow the uncertainties in the range of values of these critical inputs and improve the accuracy of the modeling results.

132

Artificial neural networks in models of specialization, guild evolution and sympatric speciation  

E-Print Network (OSTI)

Artificial neural networks in models of specialization, guild evolution and sympatric speciation artificial neural networks (ANN) as models for the host recognition system in exploiters, illustrate how

Getz, Wayne M.

133

SPECIATION OF TRACE ORGANIC LIGANDS AND INORGANIC AND ORGANOMETALLIC COMPOUNDS IN OIL SHALE PROCESS WATERS  

E-Print Network (OSTI)

with a flameless atomic absorption detector for speciationA. , "Graphite furnace atomic absorption spectrophotometerscoupled with an atomic absorption detector," in preparation,

Fish, Richard H.

2013-01-01T23:59:59.000Z

134

Speciation of trace metals in seawater by anodic stripping voltammetry: Critical analytical steps  

Science Journals Connector (OSTI)

The speciation of trace metals in seawater based on the voltammetric (DPASV) titration ... to sample contaminations during sampling, filtration and storage, displacement of complexing equilibria in freeze storage

G. Capodaglio; G. Scarponi; G. Toscano…

135

Overview of the 2010 Carbonaceous Aerosols and Radiative Effects Study (CARES)  

SciTech Connect

Substantial uncertainties still exist in the scientific understanding of the possible interactions between urban and natural (biogenic) emissions in the production and transformation of atmospheric aerosol and the resulting impact on climate change. The U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) program's Carbonaceous Aerosol and Radiative Effects Study (CARES) carried out in June 2010 in Central Valley, California, was a comprehensive effort designed to improve this understanding. The primary objective of the field study was to investigate the evolution of secondary organic and black carbon aerosols and their climate-related properties in the Sacramento urban plume as it was routinely transported into the forested Sierra Nevada foothills area. Urban aerosols and trace gases experienced significant physical and chemical transformations as they mixed with the reactive biogenic hydrocarbons emitted from the forest. Two heavily-instrumented ground sites - one within the Sacramento urban area and another about 40 km to the northeast in the foothills area - were set up to characterize the evolution of meteorological variables, trace gases, aerosol precursors, aerosol size, composition, and climate-related properties in freshly polluted and 'aged' urban air. On selected days, the DOE G-1 aircraft was deployed to make similar measurements upwind and across the evolving Sacramento plume in the morning and again in the afternoon. The NASA B-200 aircraft, carrying remote sensing instruments, was also deployed to characterize the vertical and horizontal distribution of aerosols and aerosol optical properties within and around the plume. This overview provides: a) the scientific background and motivation for the study, b) the operational and logistical information pertinent to the execution of the study, c) an overview of key observations and initial results from the aircraft and ground-based sampling platforms, and d) a roadmap of planned data analyses and focused modeling efforts that will facilitate the integration of new knowledge into improved representations of key aerosol processes in climate models.

Zaveri, Rahul A.; Shaw, William J.; Cziczo, D. J.; Schmid, Beat; Ferrare, R.; Alexander, M. L.; Alexandrov, Mikhail; Alvarez, R. J.; Arnott, W. P.; Atkinson, D.; Baidar, Sunil; Banta, Robert M.; Barnard, James C.; Beranek, Josef; Berg, Larry K.; Brechtel, Fred J.; Brewer, W. A.; Cahill, John F.; Cairns, Brian; Cappa, Christopher D.; Chand, Duli; China, Swarup; Comstock, Jennifer M.; Dubey, Manvendra K.; Easter, Richard C.; Erickson, Matthew H.; Fast, Jerome D.; Floerchinger, Cody; Flowers, B. A.; Fortner, Edward; Gaffney, Jeffrey S.; Gilles, Mary K.; Gorkowski, K.; Gustafson, William I.; Gyawali, Madhu S.; Hair, John; Hardesty, Michael; Harworth, J. W.; Herndon, Scott C.; Hiranuma, Naruki; Hostetler, Chris A.; Hubbe, John M.; Jayne, J. T.; Jeong, H.; Jobson, Bertram T.; Kassianov, Evgueni I.; Kleinman, L. I.; Kluzek, Celine D.; Knighton, B.; Kolesar, K. R.; Kuang, Chongai; Kubatova, A.; Langford, A. O.; Laskin, Alexander; Laulainen, Nels S.; Marchbanks, R. D.; Mazzoleni, Claudio; Mei, F.; Moffet, Ryan C.; Nelson, Danny A.; Obland, Michael; Oetjen, Hilke; Onasch, Timothy B.; Ortega, Ivan; Ottaviani, M.; Pekour, Mikhail S.; Prather, Kimberly A.; Radney, J. G.; Rogers, Ray; Sandberg, S. P.; Sedlacek, Art; Senff, Christoph; Senum, Gunar; Setyan, Ari; Shilling, John E.; Shrivastava, ManishKumar B.; Song, Chen; Springston, S. R.; Subramanian, R.; Suski, Kaitlyn; Tomlinson, Jason M.; Volkamer, Rainer M.; Wallace, Hoyt A.; Wang, J.; Weickmann, A. M.; Worsnop, Douglas R.; Yu, Xiao-Ying; Zelenyuk, Alla; Zhang, Qi

2012-08-22T23:59:59.000Z

136

2, 20952131, 2002 Below-cloud aerosol  

E-Print Network (OSTI)

). In addition, the understanding of wet removal processes remains crucial in local and regional pollutionACPD 2, 2095­2131, 2002 Below-cloud aerosol removal C. Andronache Title Page Abstract Introduction-cloud aerosol removal by rainfall for observed aerosol size distributions C. Andronache Boston College, Chestnut

Paris-Sud XI, Université de

137

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

138

ARM - Measurement - Aerosol optical depth  

NLE Websites -- All DOE Office Websites (Extended Search)

depth depth ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Aerosol optical depth A measure of how much light aerosols prevent from passing through a column of atmosphere. Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments HSRL : High Spectral Resolution Lidar MPL : Micropulse Lidar MFRSR : Multifilter Rotating Shadowband Radiometer NIMFR : Normal Incidence Multifilter Radiometer Field Campaign Instruments AOS-PMFOV : Acoustical Optical Spectrometer-Photometer with Multiple

139

ARM - Measurement - Aerosol optical properties  

NLE Websites -- All DOE Office Websites (Extended Search)

properties properties ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Aerosol optical properties The optical properties of aerosols, including asymmetry factor, phase-function, single-scattering albedo, refractive index, and backscatter fraction. Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments CSPHOT : Cimel Sunphotometer NEPHELOMETER : Nephelometer Field Campaign Instruments AOS-PMFOV : Acoustical Optical Spectrometer-Photometer with Multiple

140

ARM - Measurement - Aerosol backscattered radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

backscattered radiation backscattered radiation ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Aerosol backscattered radiation The scattering of radiant energy into the hemisphere of space bounded by a plane normal to the direction of the incident radiation and lying on the same side as the incident ray. Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments AOS : Aerosol Observing System MPL : Micropulse Lidar NEPHELOMETER : Nephelometer

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

Spectroscopic Approaches for Phosphorus Speciation in Soils and other Environmental Systems  

SciTech Connect

In the past decades, environmental scientists have become increasingly involved in developing novel approaches for applying emerging spectroscopic techniques to complex environmental matrices. The objective of this review is to convey the most common chemical species of phosphorus reported for soils, sediments, model systems, and waste materials based on analyses by four spectroscopic techniques: X-ray absorption near-edge structure, nuclear magnetic resonance, Fourier transform infrared spectroscopy, and Raman spectroscopy. Unique information is provided by each technique at a level of specificity that depends in part on matrix complexity. The X-ray absorption near-edge structure and nuclear magnetic resonance techniques reveal inorganic and organic P species in intact environmental matrices or in chemical extracts, whereas the Fourier transform infrared and Raman techniques can provide more specific bonding information about mineral or adsorbed P species in model analogs of matrix components. The most common P species in soils and sediments as indicated by spectroscopy are hydroxyapatite and octacalcium phosphate minerals, phosphate adsorbed on Fe- and Al-oxides, pyrophosphates and polyphosphates, phosphate mono- and di-esters, and phosphonates. Continued advancements in spectroscopic methods should improve speciation-based models of P mobilization and transformations in the environment.

F Kizewski; A Morris; Y Liu; D Hesterberg

2011-12-31T23:59:59.000Z

142

Final Report for LDRD Project ''A New Era of Research in Aerosol/Cloud/Climate Interactions at LLNL''  

SciTech Connect

Observations of global temperature records seem to show less warming than predictions of global warming brought on by increasing concentrations of CO{sub 2} and other greenhouse gases. One of the reasonable explanations for this apparent inconsistency is that the increasing concentrations of anthropogenic aerosols may be partially counteracting the effects of greenhouse gases. Aerosols can scatter or absorb the solar radiation, directly change the planetary albedo. Aerosols, unlike CO{sub 2}, may also have a significant indirect effect by serving as cloud condensation nuclei (CCN). Increases in CCN can result in clouds with more but smaller droplets, enhancing the reflection of solar radiation. Aerosol direct and indirect effects are a strong function of the distributions of all aerosol types and the size distribution of the aerosol in question. However, the large spatial and temporal variabilities in the concentration, chemical characteristics, and size distribution of aerosols have made it difficult to assess the magnitude of aerosol effects on atmospheric radiation. These variabilities in aerosol characteristics as well as their effects on clouds are the leading sources of uncertainty in predicting future climate variation. Inventory studies have shown that the present-day anthropogenic emissions contribute more than half of fine particle mass primarily due to sulfate and carbonaceous aerosols derived from fossil fuel combustion and biomass burning. Parts of our earlier studies have been focused on developing an understanding of global sulfate and carbonaceous aerosol abundances and investigating their climate effects [Chuang et al., 1997; Penner et al., 1998]. We have also modeled aerosol optical properties to account for changes in the refractive indices with relative humidity and dry aerosol composition [Grant et al., 1999]. Moreover, we have developed parameterizations of cloud response to aerosol abundance for use in global models to evaluate the importance of aerosol/cloud interactions on climate forcing [Chuang and Penner, 1995]. Our research has been recognized as one of a few studies attempting to quantify the effects of anthropogenic aerosols on climate in the IPCC Third Assessment Report [IPCC, 2001]. Our previous assessments of aerosol climate effects were based on a general circulation model (NCAR CCM1) fully coupled to a global tropospheric chemistry model (GRANTOUR). Both models, however, were developed more than a decade ago. The lack of advanced physics representation and techniques in our current models limits us from further exploring the interrelationship between aerosol, cloud, and climate variation. Our objective is to move to a new era of aerosol/cloud/climate modeling at LLNL by coupling the most advanced chemistry and climate models and by incorporating an aerosol microphysics module. This modeling capability will enable us to identify and analyze the responsible processes in aerosol/cloud/climate interactions and therefore, to improve the level of scientific understanding for aerosol climate effects. This state-of-the-art coupled models will also be used to address the relative importance of anthropogenic and natural emissions in the spatial pattern of aerosol climate forcing in order to assess the potential of human induced climate change.

Chuang, C; Bergman, D J; Dignon, J E; Connell, P S

2002-01-31T23:59:59.000Z

143

Review of models applicable to accident aerosols  

SciTech Connect

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

144

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

SciTech Connect

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

145

Hybrid speciation with external barriers: (Asteraceae: Heliantheae), a case studyEncelia  

E-Print Network (OSTI)

Hybrid speciation with external barriers: (Asteraceae: Heliantheae), a case studyEncelia Curtis, and Rancho Santa Ana Botanic Garden #12;AbstractAbstract Most well-documented cases of homoploid hybrid of hybrid speciation in Encelia (E. virginensis and E. asperifolia) appear to follow this model. In both

Clark, Curtis

146

Aluminum speciation in aqueous fluids at deep crustal pressure and temperature  

E-Print Network (OSTI)

Aluminum speciation in aqueous fluids at deep crustal pressure and temperature Mainak Mookherjee a Abstract We investigated aluminum speciation in aqueous fluids in equilibrium with corundum using in situ Raman spectroscopy in hydrothermal diamond anvil cells to 20 kbar and 1000 °C. We have studied aluminum

Manning, Craig

147

AEROSOL DIRECT RADIATIVE EFFECTS OVER THE NORTHWEST ATLANTIC, NORTHWEST PACIFIC, AND NORTH INDIAN OCEANS  

E-Print Network (OSTI)

AEROSOL DIRECT RADIATIVE EFFECTS OVER THE NORTHWEST ATLANTIC, NORTHWEST PACIFIC, AND NORTH INDIAN, NORTHWEST PACIFIC, AND NORTH INDIAN OCEANS: ESTIMATES BASED ON IN-SITU CHEMICAL AND OPTICAL MEASUREMENTS, Y.24 , Tang, Y.25 , Weber, R. J.26 , and Wu, Y.27 1 NOAA/PMEL, 7600 Sand Point Way NE, Seattle, WA

148

Tropospheric Aerosols Lead authors: Jost Heintzenberg Frank Raes Stephen E. Schwartz  

E-Print Network (OSTI)

-F.Graf · Jeremy M.Hales · Hartmut Herrmann Thorsten Hoffman · Barry Huebert · Rudolf B. Husar · Ruprecht Jaenicke advances in atmos- pheric chemistry were made in gas-phase photochem- istry, except perhaps for a brief-scale chemical transport models is essen- tial. As aerosol particles are strongly coupled with gas- phase

Schwartz, Stephen E.

149

Ocean–Atmosphere Interactions in the Emergence of Complexity in Simple Chemical Systems  

Science Journals Connector (OSTI)

Ocean–Atmosphere Interactions in the Emergence of Complexity in Simple Chemical Systems ... In this Account, we examine how water–air interfaces, namely, the surfaces of lakes, oceans, and atmospheric aerosols on ancient Earth, facilitated the emergence of complex structures necessary for life. ... Aerosols are liquid or solid suspensions in air with a broad, power law size distribution. ...

Elizabeth C. Griffith; Adrian F. Tuck; Veronica Vaida

2012-04-17T23:59:59.000Z

150

An Aerosol Condensation Model for Sulfur Trioxide  

SciTech Connect

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

151

Examination of the Effects of Sea Salt Aerosols on Southeast Texas Ozone and Secondary Organic Aerosol  

E-Print Network (OSTI)

of this research is to examine sea salt aerosols and their impact on polluted environments. Sea salt aerosols act as Cloud Condensation Nuclei (CCN) as well as providing a surface for heterogeneous reactions. Such reactions have implications for trace gases...

Benoit, Mark David

2013-02-06T23:59:59.000Z

152

Dosimeter for monitoring vapors and aerosols of organic compounds  

DOE Patents (OSTI)

A dosimeter is provided for collecting and detecting vapors and aerosols of organic compounds. The dosimeter comprises a lightweight, passive device that can be conveniently worn by a person as a badge or placed at a stationary location. The dosimeter includes a sample collector comprising a porous web treated with a chemical for inducing molecular displacement and enhancing phosphorescence. Compounds are collected onto the web by molecular diffusion. The web also serves as the sample medium for detecting the compounds by a room temperature phosphorescence technique. 7 figs.

Vo-Dinh, T.

1987-07-14T23:59:59.000Z

153

ARM - PI Product - Direct Aerosol Forcing Uncertainty  

NLE Websites -- All DOE Office Websites (Extended Search)

ProductsDirect Aerosol Forcing Uncertainty ProductsDirect Aerosol Forcing Uncertainty Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Direct Aerosol Forcing Uncertainty Site(s) NSA SGP TWP General Description 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

154

ARM - Field Campaign - Two-Column Aerosol Project (TCAP)  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsTwo-Column Aerosol Project (TCAP) govCampaignsTwo-Column Aerosol Project (TCAP) Campaign Links TCAP website Related Campaigns Two-Column Aerosol Project (TCAP): Field Evaluation of Real-time Cloud OD Sensor TWST 2013.04.15, Scott, AMF Two-Column Aerosol Project (TCAP): Winter Aerosol Effects on Cloud Formation 2013.02.04, Cziczo, AMF Two-Column Aerosol Project (TCAP): CU GMAX-DOAS Deployment 2012.07.15, Volkamer, AMF Two-Column Aerosol Project (TCAP): Aerosol Light Extinction Measurements 2012.07.15, Dubey, AMF Two-Column Aerosol Project (TCAP): Aerial Campaign 2012.07.07, Berg, AAF Two-Column Aerosol Project (TCAP): Aerodynamic Particle Sizer 2012.07.01, Berg, AMF Two-Column Aerosol Project (TCAP): KASPRR Engineering Tests 2012.07.01, Mead, AMF Two-Column Aerosol Project (TCAP): Airborne HSRL and RSP Measurements

155

Speciation and bioavailability of zinc in amended sediments  

SciTech Connect

The speciation and bioavailability of zinc (Zn) in smelter-contaminated sediments were investigated as a function of phosphate (apatite) and organic amendment loading rate. Zinc species identified in preamendment sediment were zinc hydroxide-like phases, sphalerite, and zinc sorbed to an iron oxide via X-ray adsorption near edge structure (XANES) spectroscopy. Four months after adding the amendments to the contaminated sediment, hopeite, a Zn phosphate mineral, was identified indicating phosphate was binding and sequestering available Zn and Zn pore water concentrations were decreased at levels of 90% or more. Laboratory experiments indicate organic amendments exhibit a limited effect and may hinder sequestration of pore water Zn when mixed with apatite. The acute toxicity of the sediment Zn was evaluated with Hyalella azteca, and bioaccumulation of Zn with Lumbriculus variegates. The survivability of H. azteca increased as a function of phosphate (apatite) loading rate. In contaminated sediment without apatite, no specimens of H. azteca survived. The bioaccumulation of Zn in L. variegates also followed a trend of decreased bioaccumulation with increased phosphate loading in the contaminated sediment. The research supports an association between Zn speciation and bioavailability.

Williams, Aaron G.B.; Scheckel, Kirk G.; McDermott, Gregory; Gratson, David; Neptune, Dean; Ryan, James A.

2011-12-09T23:59:59.000Z

156

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

157

Separating Cloud Forming Nuclei from Interstitial Aerosol  

SciTech Connect

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

158

Carbonaceous Aerosol Study Using Advanced Particle Instrumentation  

E-Print Network (OSTI)

particles from the combustion of biomass fuels. Environ.range transport of biomass combustion aerosols. Environ.during the open combustion of biomass in the laboratory, J.

Qi, Li

2010-01-01T23:59:59.000Z

159

Comparative Analysis of Urban Atmospheric Aerosol by Particle...  

NLE Websites -- All DOE Office Websites (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...

160

The Two-Column Aerosol Project Definitions TCAP Educational  

NLE Websites -- All DOE Office Websites (Extended Search)

What's the big deal about aerosols? The Two-Column Aerosol Project Definitions TCAP Educational Outreach Activity About ARM: The Atmospheric Radiation Measurement (ARM) Climate...

Note: This page contains sample records for the topic "aerosol chemical speciation" 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.


161

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

NLE Websites -- All DOE Office Websites (Extended Search)

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

162

The Indirect and Semi-Direct Aerosol Campaign  

SciTech Connect

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

163

Overview of the COPS Aerosol and Cloud Microphysics (ACM) Subgroup...  

NLE Websites -- All DOE Office Websites (Extended Search)

properties of orographically induced clouds and how do these depend on dynamics, thermodynamics, and aerosol microphysics? * What is the role of aerosols and changing cloud...

164

Molecular Chemistry of Organic Aerosols Through the Application...  

NLE Websites -- All DOE Office Websites (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...

165

Development of a Fast Time-Resolved Aerosol Collector (Fast TRAC)  

NLE Websites -- All DOE Office Websites (Extended Search)

Yu Yu & James Cowin PNNL Fast Time-Resolved Aerosol Collector ......Fast TRAC...... Xiao-Ying Yu, Ali Hashim, Martin Iedema, and James Cowin Atmospheric Sciences, Chemical Sciences Pacific Northwest National Laboratory Richland, WA Research is supported by NOAA & DOE. *Patent Pending Xiao-Ying Yu & James Cowin PNNL Cloud Microstructures ≤ 1 m Want to know the aerosols at this resolution Aircraft flies at 150 m/s Need time resolution 1 m/150 m/s = 6 ms (!!!!!) Xiao-Ying Yu & James Cowin PNNL What is TRAC? - Time-Resolved Aerosol Collector * Uses an impactor * ~ 600 TEM samples * Flow rate: 1 l/min * Time resolution: ≥ 1 min* * Applications: Off-line analysis: - particle hygroscopicity, morphology, composition.. (6.5 in) 3 , 7 lb, 12 V, 8 W 0% 20% 40% 60%

166

Spectro-microscopic Measurements of Carbonaceous Aerosol Aging in Central California  

NLE Websites -- All DOE Office Websites (Extended Search)

Spectro-microscopic Measurements of Carbonaceous Spectro-microscopic Measurements of Carbonaceous Aerosol Aging in Central California For original submission and image(s), see ARM Research Highlights http://www.arm.gov/science/highlights/ Research Highlight Atmospheric aerosols affect climate by scattering and absorbing sunlight and by modifying the properties of clouds. However, there are gaps in our understanding of chemical processes involving these airborne particulates, and these gaps contribute significantly to uncertainties in predicting future climate change. Developing more- accurate global climate models requires a more complete understanding of the aerosol lifecycle, from initial particle formation to loss through incorporation into precipitating clouds or dry deposition. In research published in the journal Atmospheric Chemistry and Physics, a team of

167

Active Spectral Nephelometry in Studies of the Condensational Activity of Submicron Aerosol  

NLE Websites -- All DOE Office Websites (Extended Search)

Active Spectral Nephelometry in Studies of the Active Spectral Nephelometry in Studies of the Condensational Activity of Submicron Aerosol M. V. Panchenko, S. A. Terpugova, and V. S. Kozlov Institute of Atmospheric Optics Russian Academy of Sciences Tomsk, Russia M. A. Sviridenkov A. M. Obukhov Institute of Atmospheric Physics Russian Academy of Sciences Moscow, Russia A. S. Kozlov Institute of Chemical Kinetics and Combustion Russian Academy of Sciences Novosibirsk, Russia Introduction Water vapor condensation and evaporation are among the main processes of the atmospheric aerosol transformation essentially affecting its optical and radiative characteristics. Most of the known methods for investigating the aerosol condensation activity are based on measurements of only the changes in the

168

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

SciTech Connect

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

169

Spectro-Microscopic Measurements of Carbonaceous Aerosol Aging in Central California  

SciTech Connect

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

170

Chemical and Physical Investigation of Secondary Organic Aerosol Formation  

E-Print Network (OSTI)

M. , Seinfeld, J. H. , Wallington, T. J. , Yarwood, G. : TheM. , Seinfeld, J. H. , Wallington, T. J. , Yarwood, G. : TheM. D. , Sokolov, O. , Wallington, T. J. , Takekawa, H. ,

Nakao, Shunsuke

2012-01-01T23:59:59.000Z

171

Capstone Depleted Uranium Aerosol Biokinetics, Concentrations, and Doses  

SciTech Connect

One of the principal goals of the Capstone Depleted Uranium (DU) Aerosol Study was to quantify and characterize DU aerosols generated inside armored vehicles by perforation with a DU penetrator. This study consequently produced a database in which the DU aerosol source terms were specified both physically and chemically for a variety of penetrator-impact geometries and conditions. These source terms were used to calculate radiation doses and uranium concentrations for various scenarios as part of the Capstone DU Human Health Risk Assessment (HHRA). This paper describes the scenario-related biokinetics of uranium, and summarizes intakes, chemical concentrations to the organs, and E(50) and HT(50) for organs and tissues based on exposure scenarios for personnel in vehicles at the time of perforation as well as for first responders. For a given exposure scenario (duration time and breathing rates), the range of DU intakes among the target vehicles and shots was not large, about a factor of 10, with the lowest being from a ventilated operational Abrams tank and the highest being for an unventilated Abrams with DU penetrator perforating DU armor. The ranges of committed effective doses were more scenario-dependent than were intakes. For example, the largest range, a factor of 20, was shown for scenario A, a 1-min exposure, whereas, the range was only a factor of two for the first-responder scenario (E). In general, the committed effective doses were found to be in the tens of mSv. The risks ascribed to these doses are discussed separately.

Guilmette, Raymond A.; Miller, Guthrie; Parkhurst, MaryAnn

2009-02-26T23:59:59.000Z

172

Genomic Speciation and Adaptation in Aquilegia (2011 JGI User Meeting)  

ScienceCinema (OSTI)

The U.S. Department of Energy Joint Genome Institute (JGI) invited scientists interested in the application of genomics to bioenergy and environmental issues, as well as all current and prospective users and collaborators, to attend the annual DOE JGI Genomics of Energy & Environment Meeting held March 22-24, 2011 in Walnut Creek, Calif. The emphasis of this meeting was on the genomics of renewable energy strategies, carbon cycling, environmental gene discovery, and engineering of fuel-producing organisms. The meeting features presentations by leading scientists advancing these topics. Scott Hodges of the University of California, Santa Barbara gives a presentation on "Genomic Speciation and Adaptation in Aquilegia" at the 6th annual Genomics of Energy & Environment Meeting on March 23, 2011

Hodges, Scott [University of California, Santa Barbara

2011-06-03T23:59:59.000Z

173

Technetium Inventory, Distribution, and Speciation in Hanford Tanks  

SciTech Connect

The purpose of this report is three fold: 1) assemble the available information regarding technetium (Tc) inventory, distribution between phases, and speciation in Hanford’s 177 storage tanks into a single, detailed, comprehensive assessment; 2) discuss the fate (distribution/speciation) of Tc once retrieved from the storage tanks and processed into a final waste form; and 3) discuss/document in less detail the available data on the inventory of Tc in other "pools" such as the vadose zone below inactive cribs and trenches, below single-shell tanks (SSTs) that have leaked, and in the groundwater below the Hanford Site. A thorough understanding of the inventory for mobile contaminants is key to any performance or risk assessment for Hanford Site facilities because potential groundwater and river contamination levels are proportional to the amount of contaminants disposed at the Hanford Site. Because the majority of the total 99Tc produced at Hanford (~32,600 Ci) is currently stored in Hanford’s 177 tanks (~26,500 Ci), there is a critical need for knowledge of the fate of this 99Tc as it is removed from the tanks and processed into a final solid waste form. Current flow sheets for the Hanford Waste Treatment and Immobilization Plant process show most of the 99Tc will be immobilized as low-activity waste glass that will remain on the Hanford Site and disposed at the Integrated Disposal Facility (IDF); only a small fraction will be shipped to a geologic repository with the immobilized high-level waste. Past performance assessment studies, which focused on groundwater protection, have shown that 99Tc would be the primary dose contributor to the IDF performance.

Serne, R. Jeffrey; Rapko, Brian M.

2014-05-02T23:59:59.000Z

174

Speciation-rate dependence in speciesarea relationships Simone Pigolotti a,, Massimo Cencini b,c  

E-Print Network (OSTI)

, for which we separate the effect of the speciation rate from that of the different species lifespans. We number of species (S) present in a sample area (A) of a given ecosystem and usually display a triphasic

Cencini, Massimo

175

Speciation and oxidation kinetics of arsenic in the thermal springs of Wiesbaden spa, Germany  

Science Journals Connector (OSTI)

Since 1886 arsenic has been known to be present as a trace component in the Wiesbaden thermal waters at concentrations of over 100 µg L–1. In this study for the first time molecular level speciation of arsenic w...

Susanne P. Schwenzer; Caterina E. Tommaseo…

2001-12-01T23:59:59.000Z

176

BNL | Mobile Aerosol Observing System (MAOS)  

NLE Websites -- All DOE Office Websites (Extended Search)

Mobile Aerosol Observing System (MAOS) Mobile Aerosol Observing System (MAOS) The Mobile Aerosol Observing System (MAOS) is a platform and instrument suite for Intensive Operation Periods (IOPs) to conduct in situ measurements of aerosols and their precursors. MAOS is part of the ARM Climate Research Facility. Physically MAOS is contained in two 20' SeaTainers custom adapted to provide a sheltered laboratory environment for operators and instruments even under harsh conditions. The two structures are designated MAOS-A and MAOS-C for Aerosol and Chemistry respectively. Although independent, with separate data systems, inlets and power distribution, the two structures are normally a single operating unit. The two enclosures comprising MAOS are designed for rapid deployment. All components (except for the Radar Wind Profiler) are transported internally

177

The Opposed Migration Aerosol Classifier (OMAC)  

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The Opposed Migration Aerosol Classifier (OMAC) The Opposed Migration Aerosol Classifier (OMAC) Speaker(s): Harmony Gates Date: February 22, 2007 - 12:00pm Location: 90-4133 Seminar Host/Point of Contact: Melissa Lunden A new differential mobility classifier will be described. The instrument classifies aerosol particles in a channel flow between porous (or screen) electrodes. The aerosol enters the channel parallel to the porous electrodes, while a larger, particle-free cross-flow enters through one of the porous electrode. A potential difference between electrodes causes the charged aerosol particles to migrate upstream against the cross-flow. Only particles whose upward migration velocity balances the cross flow will be transmitted along the path of the classifier. Simulations of the OMAC show that it should give the same resolution at the traditional

178

Impact of Two Water Management Systems on Arsenic Speciation and Microbial Populations in Rice Rhizosphere  

E-Print Network (OSTI)

IMPACT OF TWO WATER MANAGEMENT SYSTEMS ON ARSENIC SPECIATION AND MICROBIAL POPULATIONS IN RICE RHIZOSPHERE A Dissertation by ANIL KUMAR C. SOMENAHALLY Submitted to the Office of Graduate Studies of Texas A&M University... in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY December 2010 Major Subject: Soil Science Impact of Two Water Management Systems on Arsenic Speciation and Microbial...

Somenahally, Anil Kumar C.

2012-02-14T23:59:59.000Z

179

Mercury speciation in Galveston Bay, Texas: the importance of complexation by natural organic ligands  

E-Print Network (OSTI)

MERCURY SPECIATION IN GALVESTON BAY, TEXAS: THE IMPORTANCE OF COMPLEXATION BY NATURAL ORGANIC LIGANDS A Dissertation by SEUNGHEE HAN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of DOCTOR OF PHILOSOPHY December 2004 Major Subject: Oceanography MERCURY SPECIATION IN GALVESTON BAY, TEXAS: THE IMPORTANCE OF COMPLEXATION BY NATURAL ORGANIC LIGANDS A Dissertation by SEUNGHEE HAN...

Han, Seunghee

2005-02-17T23:59:59.000Z

180

Sorption Speciation of Nickel(II) onto Ca-Montmorillonite: Batch, EXAFS Techniques and Modeling  

E-Print Network (OSTI)

1 Sorption Speciation of Nickel(II) onto Ca-Montmorillonite: Batch, EXAFS Techniques and Modeling, 44307 Nantes cedex 03, France The sorption speciation of Ni(II) on Ca-montmorillonite was evaluated(II) sorption as well as the local atomic structure of the adsorbed Ni(II) ions. At 0.001 mol/L Ca(NO3)2 and low

Paris-Sud XI, Université de

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181

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

182

Applications of Capstone Depleted Uranium Aerosol Risk Data to Military Combat Risk Management  

SciTech Connect

Risks to personnel engaged in military operations include not only the threat of enemy firepower but also risks from exposure to other hazards such as radiation. Combatant commanders of the U. S. Army carefully weigh risks of casualties before implementing battlefield actions using an established paradigm that take these risks into consideration. As a result of the inclusion of depleted uranium (DU) anti-armor ammunition in the conventional (non-nuclear) weapons arsenal, the potential for exposure to DU aerosols and its associated chemical and radiological effects becomes an element of the commanders’ risk assessment. The Capstone DU Aerosol Study measured the range of likely DU oxide aerosol concentrations created inside a combat vehicle perforated with a DU munition, and the Capstone Human Health Risk Assessment (HHRA) estimated the associated doses and calculated risks. This paper focuses on the development of a scientific approach to adapt the risks from DU’s non uniform dose distribution within the body using the current U.S. Department of Defense (DoD) radiation risk management approach. The approach developed equates the Radiation Exposure Status (RES) categories to the estimated radiological risks of DU and makes use of the Capstone-developed Renal Effects Group (REG) as a measure of chemical risk from DU intake. Recommendations are provided for modifying Army guidance and policy in order to better encompass the potential risks from DU aerosol inhalation during military operations.

Daxon, Eric G.; Parkhurst, MaryAnn; Melanson, Mark A.; Roszell, Laurie E.

2009-03-01T23:59:59.000Z

183

Iodine-129 and Iodine-127 speciation in groundwater at the Hanford Site, U.S.: iodate incorporation into calcite  

SciTech Connect

The Hanford Site, the most contaminated nuclear site in the United States, has large radioactive waste plumes containing high 129I levels. The geochemical transport and fate of radioiodine depends largely on its chemical speciation that is greatly affected by environmental factors. This study reports, for the first time, the speciation of stable and radioactive iodine in the groundwater from the Hanford Site. Iodate was the dominant species and accounts for up to 84%, followed by organo-iodine and minimal levels of iodide. The relatively high pH and oxidizing environment may have prevented iodate reduction. Our results identified that calcite precipitation caused by degassing of CO2 during deep groundwater sampling incorporated between 7 to 40% of dissolved iodine (including 127I and 129I) that was originally in the groundwater, transforming dissolved to particulate iodate during sampling. In order to understand the mechanisms underlying iodine incorporation by calcite, laboratory experiments were carried out to replicate this iodine sequestering processes. Two methods were utilized in this study, 1) addition of sodium carbonate; 2) addition of calcium chloride followed by sodium carbonate where the pH was well controlled at ~8.2, which is close to the average pH of Hanford Site groundwater. It was demonstrated that iodate was the main species incorporated into calcite and this incorporation process could be impeded by elevated pH and decreasing ionic strength in groundwater. This study provides critical information for predicting the long-term fate and transport of 129I at the Hanford Site and reveals a potential means for improved remediation strategies of 129I.

Zhang, Saijin [Texas A and M Univ. at Galveston, TX (United States). Dept. of Marine Science; Xu, Chen [Texas A and M Univ. at Galveston, TX (United States). Dept. of Marine Science; Creeley, Danielle [Texas A and M Univ. at Galveston, TX (United States). Dept. of Marine Science; Ho, Yi-Fang [Texas A and M Univ. at Galveston, TX (United States). Dept. of Marine Science; Li, Hsiu-Ping [Texas A and M Univ. at Galveston, TX (United States). Dept. of Marine Science; Grandbois, Russell [Texas A and M Univ. at Galveston, TX (United States). Dept. of Marine Science; Schwehr, Kathy [Texas A and M Univ. at Galveston, TX (United States). Dept. of Marine Science; Kaplan, Daniel I. [Savannah River National Laboratory, Aiken, SC (United States); Yeager, Chris [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Wellman, Dawn M. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Santschi, Peter H. [Texas A and M Univ. at Galveston, TX (United States). Dept. of Marine Science

2013-07-25T23:59:59.000Z

184

Determination of the elemental distribution and chemical speciation in highly heterogeneous cementitious materials using  

E-Print Network (OSTI)

-barrier concepts developed worldwide for the safe disposal of hazardous and radioactive waste [e.g., 1 and to construct the engineered barrier systems (container, backfill and liner materials) of repositories for radioactive waste. Thus, hardened cement paste (HCP) is an important component of the engineered barrier

185

Partitioning and chemical speciation of mercury, arsenic, and selenium during inert gas oil shale retorting  

SciTech Connect

A Green River shale from Colorado and a New Albany shale from Kentucky were retorted in the Pacific Northwest Laboratory 6-kg bench-scale retort at 1 to 2C/min and at 10C/min to maximum temperatures of 500 and 750C under a nitrogen sweep gas. The product streams were analyzed using a variety of methods including Zeeman atomic aabsortion spectroscopy, microwave-induced helium plasma spectroscopy, x-ray fluorescence, instrumental neutron activation analysis, high-pressure liquid and silica gel column chromatography, and mercury cold vapor atomic absorption. The results obtained using these analytical methods indicate the the distribution of mercury, arsenic, and selenium in the product stream is a function of oil shale type, heating rates, and maximum retorting temperatures. 23 refs., 15 figs., 5 tabs.

Olsen, K.B.; Evans, J.C.; Sklarew, D.S.; Girvin, D.C.; Nelson, C.L.; Lepel, E.A.; Robertson, D.E.; Sanders, R.W.

1985-12-01T23:59:59.000Z

186

The effects of soil type and chemical treatment on nickel speciation in refinery enriched soils  

E-Print Network (OSTI)

: A multi-technique investigation David H. McNear Jr. a,*, Rufus L. Chaney b , Donald L. Sparks c of 29 km2 of land with Ni concentrations exceeding the Canadian Ministry of the Environment's remedial as a remediation strategy for this area. In this paper we use multiple techniques to directly assess the role soil

187

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

188

E-Print Network 3.0 - aerosol number distributions Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

inorganic composition PILS-IC Summary: 3563 nephelometers Aerosol number concentration CNC (TSI 3010, 3025) Aerosol size distribution DMA... and APS Non-volatile aerosol size...

189

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

NLE Websites -- All DOE Office Websites (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...

190

E-Print Network 3.0 - aerosol jet system Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

-controlled laminar aerosol jets and their application for studying aerosol combustion processes Author(s): Shoshin Y... 2002 Times Cited: 6 48. Title: Exhaust aerosol of a...

191

CARES: Carbonaceous Aerosol and Radiative Effects Study Science Plan  

SciTech Connect

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

192

Capstone Depleted Uranium Aerosols: Generation and Characterization  

SciTech Connect

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

193

MERCURY SPECIATION SAMPLING AT NEW CENTURY ENERGY'S VALMONT STATION  

SciTech Connect

The 1990 Clean Air Act Amendments required the U.S. Environmental Protection Agency (EPA) to determine whether the presence of mercury in the stack emissions from fossil fuel-fired electric utility power plants poses an unacceptable public health risk. EPA's conclusions and recommendations were presented in the ''Mercury Study Report to Congress'' and ''Study of Hazardous Air Pollutant Emissions from Electric Utility Steam Generating Units''. The first report addressed both the human health and environmental effects of anthropogenic mercury emissions, while the second addressed the risk to public health posed by the emission of mercury and other hazardous air pollutants from steam electric generating units. Although these reports did not state that mercury controls on coal-fired electric power stations would be required given the current state of the art, they did indicate that the EPA views mercury as a potential threat to human health. Therefore, it was concluded that mercury controls at some point may be necessary. EPA also indicated that additional research/information was necessary before any definitive statement could be made. In an effort to determine the amount and types of mercury being emitted into the atmosphere by coal-fired power plants, EPA in late 1998 issued an information collection request (ICR) that required all coal-fired power plants to analyze their coal and submit the results to EPA on a quarterly basis. In addition, about 85 power stations were required to measure the speciated mercury concentration in the flue gas. These plants were selected on the basis of plant configuration and coal type. The Valmont Station owned and operated by New Century Energy in Boulder, Colorado, was selected for detailed mercury speciation of the flue gas as part of the ICR process. New Century Energy, in a tailored collaboration with EPRI and the U.S. Department of Energy, contracted with the Energy & Environmental Research Center (EERC) to do a study evaluating the behavior of mercury at the Valmont Station. The activities conducted at the Valmont Station by the EERC not only included the sampling needed to meet the requirements of the ICR, but involved a much more extensive mercury research program. The following objectives for the sampling at New Century Energy's Valmont Station were accomplished: (1) Successfully complete all of the mercury sampling and reporting requirements of the ICR. (2) Determine the variability in mercury concentrations at the stack using mercury continuous emission monitors (CEMs). (3) Calculate mercury mass balances and emission rates. (4) Determine the mercury concentration in the fly ash as a function of particle size. (5) Determine the impact of a fabric filter on mercury emissions for a western bituminous coal.

Dennis L. Laudal

2000-04-01T23:59:59.000Z

194

Emissions of trace gases and aerosols during the open combustion of biomass  

NLE Websites -- All DOE Office Websites (Extended Search)

Emissions of trace gases and aerosols during the open combustion of biomass Emissions of trace gases and aerosols during the open combustion of biomass in the laboratory Title Emissions of trace gases and aerosols during the open combustion of biomass in the laboratory Publication Type Journal Article Year of Publication 2009 Authors McMeeking, Gavin R., Sonia M. Kreidenweis, Stephen Baker, Christian M. Carrico, Judith C. Chow, Jeffrey Collett L. Jr., Wei Min Hao, Amanda S. Holden, Thomas W. Kirchstetter, William C. Malm, Hans Moosmuller, Amy P. Sullivan, and Cyle E. Wold Journal Journal of Geophysical Research Volume 114 Abstract We characterized the gas- and speciated aerosol-phase emissions from the open combustion of 33 different plant species during a series of 255 controlled laboratory burns during the Fire Laboratory at Missoula Experiments (FLAME). The plant species we tested were chosen to improve the existing database for U.S. domestic fuels: laboratory-based emission factors have not previously been reported for many commonly burned species that are frequently consumed by fires near populated regions and protected scenic areas. The plants we tested included the chaparral species chamise, manzanita, and ceanothus, and species common to the southeastern United States (common reed, hickory, kudzu, needlegrass rush, rhododendron, cord grass, sawgrass, titi, and wax myrtle). Fire-integrated emission factors for gas-phase CO2, CO, CH4, C2-4 hydrocarbons, NH3, SO2, NO, NO2, HNO3, and particle-phase organic carbon (OC), elemental carbon (EC), SO4 2, NO3, Cl, Na+, K+, and NH4 + generally varied with both fuel type and with the fire-integrated modified combustion efficiency (MCE), a measure of the relative importance of flaming- and smoldering-phase combustion to the total emissions during the burn. Chaparral fuels tended to emit less particulate OC per unit mass of dry fuel than did other fuel types, whereas southeastern species had some of the largest observed emission factors for total fine particulate matter. Our measurements spanned a larger range of MCE than prior studies, and thus help to improve estimates of the variation of emissions with combustion conditions for individual fuels.

195

Atmospheric Aerosols Aging Involving Organic Compounds and Impacts on Particle Properties  

E-Print Network (OSTI)

) and chemical reactions (oxidation of particles by gas-phase oxidants and heterogeneous reactions between gas molecules and particles).5 For example, when initially formed, soot particles are hydrophobic and fractal in morphology, with low effective density... particles have a ? value of 1.0; whereas fractal ones will have ? > 1.0. Measurements of Aerosol Optical Properties The optical system consisted of a commercial integrating Nephelometer (Model 3563, TSI) and a CRDS connected in series.20 The particles...

Qiu, Chong

2013-02-01T23:59:59.000Z

196

Southern hemisphere tropospheric aerosol microphysics  

SciTech Connect

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

197

ARM - Measurement - Aerosol particle size distribution  

NLE Websites -- All DOE Office Websites (Extended Search)

particle size distribution particle size distribution ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Aerosol particle size distribution The number of aerosol particles present in any given volume of air within a specificied size range Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments SMPS : Scanning mobility particle sizer TDMA : Tandem Differential Mobility Analyzer UHSAS : Ultra-High Sensitivity Aerosol Spectrometer Field Campaign Instruments

198

NASA's Aerosol-Cloud-Ecosystems (ACE) Mission  

Science Journals Connector (OSTI)

Plans for NASA’s Aerosol-Cloud-Ecosystem (ACE) mission is described. Recommended by Earth Science Decadal Survey in 2007, ACE is nominally planned for a 2021 launch. ACE is...

Starr, David O'C

199

Aerosol Best Estimate Value-Added Product  

SciTech Connect

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

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

2012-07-19T23:59:59.000Z

200

ARM - Publications: Science Team Meeting Documents: A decade long aerosol  

NLE Websites -- All DOE Office Websites (Extended Search)

A decade long aerosol and cloud statistics and aerosol indirect effect at A decade long aerosol and cloud statistics and aerosol indirect effect at the ARM SGP site Min, Qilong State University of New York at Albany Duan, Minzheng State University of New York at Albany Harrison, Lee State University of New York Joseph, Everette Howard University Twelve-year data of MFRSR and MWR have been used to derive aerosol and cloud optical properties at the ARM SGP. Diurnal, monthly, seasonal and interannual variability of aerosol (optical depth and Angstrom coefficient) and cloud (optical depth and effective radius) have been analyzed. We specially focused on aerosol-cloud interactions. We found a signature of indirect aerosol effect for summer data: increased aerosol index has a statistically-significant anti-correlation with mean effective radius. No

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

DETERMINATION OF RADIAL MOMENTS OF AN AEROSOL  

NLE Websites -- All DOE Office Websites (Extended Search)

DETERMINATION OF RADIAL MOMENTS OF AN AEROSOL DETERMINATION OF RADIAL MOMENTS OF AN AEROSOL SIZE DISTRIBUTION FROM MEASUREMENTS OF LIGHT TRANSMITTANCE AND SCATTERING Ernie R. Lewis and Stephen E. Schwartz Brookhaven National Laboratory, Upton, NY 11933 ses@bnl.gov elewis@bnl.gov MOMENTS FROM MEASUREMENTS As each of the measured quantities is linear in the size distribution dn/dr, it is possible to construct linear combinations of measurements that yield

202

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

203

Electrically Driven Technologies for Radioactive Aerosol Abatement  

SciTech Connect

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

204

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

205

Aerosol analysis for the regional air pollution study. Final report  

SciTech Connect

The design and operation of an aerosol sampling and analysis program implemented during the 1975 to 1977 St. Louis Regional Air Pollution Study is described. A network of ten samplers were operated at selected sites in the St. Louis area and the total mass and elemental composition of the collected particulates were determined. Sampling periods of 2 to 24 hours were employed. The samplers were capable of collecting aerosol particles in two distinct size ranges corresponding to fine (< 2.4 ..mu..m diameter) and coarse (> 2.4 ..mu..m diameter) particles. This unique feature allowed the separation of the particulate samples into two distinct fractions with differing chemical origins and health effects. The analysis methods were also newly developed for use in the St. Louis RAPS study. Total particulate mass was measured by a beta-particle attenuation method in which a precision of +- 5 ..mu..m/cm/sup 2/ could be obtained in a one minute measurement time. Elemental compositions of the samples were determined using an energy dispersive x-ray fluorescence method in which detectable limits of 5 ng/cm/sup 2/ or less were routinely achieved for elements ranging in atomic number from Al to Pb. The advantages of these analytical methods over more conventional techniques arise from the ability to automate the measurements. During the course of the two year study, a total of more than 35,000 individual samples were processed and a total of 28 concentrations measured for each sample.

Jaklevic, J.M.; Gatti, R.C.; Goulding, F.S.; Loo, B.W.; Thompson, A.C.

1980-05-01T23:59:59.000Z

206

Atmospheric Aerosol Chemistry Analyzer: Demonstration of feasibility  

SciTech Connect

This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project objective was to demonstrate the technical feasibility of an Atmospheric Aerosol Chemistry Analyzer (AACA) that will provide a continuous, real-time analysis of the elemental (major, minor and trace) composition of atmospheric aerosols. The AACA concept is based on sampling the atmospheric aerosol through a wet cyclone scrubber that produces an aqueous suspension of the particles. This suspension can then be analyzed for elemental composition by ICP/MS or collected for subsequent analysis by other methods. The key technical challenge was to develop a wet cyclone aerosol sampler suitable for respirable particles found in ambient aerosols. We adapted an ultrasonic nebulizer to a conventional, commercially available, cyclone aerosol sampler and completed collection efficiency tests for the unit, which was shown to efficiently collect particles as small as 0.2 microns. We have completed the necessary basic research and have demonstrated the feasibility of the AACA concept.

Mroz, E.J.; Olivares, J.; Kok, G.

1996-04-01T23:59:59.000Z

207

E-Print Network 3.0 - aerosol microphysical characteristics Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

new particle formation, aerosol microphysical evolution, three-dimensional transport, and wet... of aerosol microphysical properties. Some of ... Source: Brookhaven...

208

Na, Mg, Ni and Cs distribution and speciation after long-term alteration of a simulated nuclear waste glass  

E-Print Network (OSTI)

distribution and speciation of Na, Mg, Ni and Cs in a simulated (inactive) nuclear waste glass were studied and Cs represent dose determining long-lived radionuclides (59 Ni, 135 Cs) in vitrified nuclear wasteNa, Mg, Ni and Cs distribution and speciation after long-term alteration of a simulated nuclear

209

Chemical deposition methods using supercritical fluid solutions  

DOE Patents (OSTI)

A method for depositing a film of a desired material on a substrate comprises dissolving at least one reagent in a supercritical fluid comprising at least one solvent. Either the reagent is capable of reacting with or is a precursor of a compound capable of reacting with the solvent to form the desired product, or at least one additional reagent is included in the supercritical solution and is capable of reacting with or is a precursor of a compound capable of reacting with the first reagent or with a compound derived from the first reagent to form the desired material. The supercritical solution is expanded to produce a vapor or aerosol and a chemical reaction is induced in the vapor or aerosol so that a film of the desired material resulting from the chemical reaction is deposited on the substrate surface. In an alternate embodiment, the supercritical solution containing at least one reagent is expanded to produce a vapor or aerosol which is then mixed with a gas containing at least one additional reagent. A chemical reaction is induced in the resulting mixture so that a film of the desired material is deposited.

Sievers, Robert E. (Boulder, CO); Hansen, Brian N. (Boulder, CO)

1990-01-01T23:59:59.000Z

210

Small-Scale Spray Releases: Initial Aerosol Test Results  

SciTech Connect

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

211

Small-Scale Spray Releases: Initial Aerosol Test Results  

SciTech Connect

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

212

Large-Scale Spray Releases: Initial Aerosol Test Results  

SciTech Connect

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

213

Source Attribution of Light Absorbing Aerosol in Arctic Snow  

NLE Websites -- All DOE Office Websites (Extended Search)

Source Attribution of Light Absorbing Source Attribution of Light Absorbing Aerosol in Arctic Snow (Preliminary analysis of 2008-2009 data) Outline * Receptor modeling overview * Results from 2007 data set * New goals arising from analysis of 2007 data * New data for 2008 * New data for 2009 * Tentative conclusions * Future analysis i Factor profiles from 2007 analysis Source attribution of Black Carbon from 2007 analysis Goals/Issues suggested by the analysis of the 2007 data set * Are there seasonal differences in the source strengths? * Are there other LAA chemical components besides black carbon. What are their sources? * Can the various data sets available (e.g., 2007, 2008, 2009) be combined in a single large PMF analysis 2008 Data Set For Receptor Analysis * 42 samples from Eastern Siberia including 4 depth profiles

214

Canadian House Dust Study: Lead Bioaccessibility and Speciation  

SciTech Connect

Vacuum samples were collected from 1025 randomly selected urban Canadian homes to investigate bioaccessible Pb (Pb{sub S}) concentrations in settled house dust. Results indicate a polymodal frequency distribution, consisting of three lognormally distributed subpopulations defined as 'urban background' (geomean 58 {micro}g g{sup -1}), 'elevated' (geomean 447 {micro}g g{sup -1}), and 'anomalous' (geomean 1730 {micro}g g{sup -1}). Dust Pb{sub S} concentrations in 924 homes (90%) fall into the 'urban background' category. The elevated and anomalous subpopulations predominantly consist of older homes located in central core areas of cities. The influence of house age is evidenced by a moderate correlation between house age and dust Pb{sub S} content (R{sup 2} = 0.34; n = 1025; p < 0.01), but it is notable that more than 10% of homes in the elevated/anomalous category were built after 1980. Conversely, the benefit of home remediation is evidenced by the large number of homes (33%) in the background category that were built before 1960. The dominant dust Pb species determined using X-ray Absorption Spectroscopy were as follows: Pb carbonate, Pb hydroxyl carbonate, Pb sulfate, Pb chromate, Pb oxide, Pb citrate, Pb metal, Pb adsorbed to Fe- and Al-oxyhydroxides, and Pb adsorbed to humate. Pb bioaccessibility estimated from solid phase speciation predicts Pb bioaccessibility measured using a simulated gastric extraction (R{sup 2} = 0.85; n = 12; p < 0.0001). The trend toward increased Pb bioaccessibility in the elevated and anomalous subpopulations (75% {+-} 18% and 81% {+-} 8%, respectively) compared to background (63% {+-} 18%) is explained by the higher proportion of bioaccessible compounds used as pigments in older paints (Pb carbonate and Pb hydroxyl carbonate). This population-based study provides a nationally representative urban baseline for applications in human health risk assessment and risk management.

P Rasmussen; S Beauchemin; M Chenier; C Levesque; L MacLean; L Marrow; H Jones-Otazo; S Petrovic; L McDonald; H Gardner

2011-12-31T23:59:59.000Z

215

Factors Controlling Redox Speciation of Plutonium and Neptunium in Extraction Separation Processes  

SciTech Connect

The objective of the project was to examine the factors controlling redox speciation of plutonium and neptunium in UREX+ extraction in terms of redox potentials, redox mechanism, kinetics and thermodynamics. Researchers employed redox-speciation extractions schemes in parallel to the spectroscopic experiments. The resulting distribution of redox species w studied uring spectroscopic, electrochemical, and spectro-electrochemical methods. This work reulted in collection of data on redox stability and distribution of redox couples in the nitric acid/nitrate electrolyte and the development of redox buffers to stabilize the desired oxidation state of separated radionuclides. The effects of temperature and concentrations on the redox behavior of neptunium were evaluated.

Paulenova, Alena [Principal Investigator; Vandegrift, III, George F. [Collaborator

2013-09-24T23:59:59.000Z

216

Atmospheric Radiation Measurement (ARM) Data from Shouxian, China for the Study of Aerosol Indirect Effects in China  

DOE Data Explorer (OSTI)

In a complex ARM Mobile Facility (AMF) deployment, monitoring data was collected at four locations in China during 2008. The various sites are located in regions with different climate regimes and with high aerosol loadings of different optical, physical, and chemical properties. Measurements obtained at all the AMF sites during the 8-month deployment in China will help scientists to validate satellite-based findings, understand the mechanisms of the aerosol indirect effects in the region, and examine the roles of aerosols in affecting regional climate and atmospheric circulation, with a special focus on the impact of the East Asian monsoon system. As with other collections from the ARM Mobile Facility, the datasets are available from the ARM Archive. The ARM Archive physically resides at the Oak Ridge National Laboratory.

217

DOE research on atmospheric aerosols  

SciTech Connect

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

218

ARM Aerosol Working Group Meeting  

NLE Websites -- All DOE Office Websites (Extended Search)

and MFRSR Measurements ARM STM 2008 Norfolk, VA Connor Flynn 1 , Annette Koontz 1 , Anne Jefferson 2 , Jim Barnard 1 , Sally McFarlane 1 1 Pacific Northwest National Laboratory 2 CIRES, University of Colorado, Boulder Progress towards ARM DOE 2008 Performance Metric 3 & 4 * Produce and make available new continuous time series of aerosol total column depth, based on results from the AMF deployment in Niger, Africa. * Produce and make available new continuous time series of retrieved dust properties, based on results from the AMF deployment in Niger, Africa. 0 100 200 300 400 0 20 40 60 80 100 ITF movement and surface RH % RH day of year (2006) 0 100 200 300 400 0 50 100 150 200 250 300 350 day of year wind direction (N = 0, E = 90) 2 4 6 8 10 12 14 Wind speed m/s 0 100 200 300 1.4 1.6 1.8 2 MFRSR Vo for filter2, Niamey

219

ARM - Field Campaign - Carbonaceous Aerosol and Radiative Effects Study  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsCarbonaceous Aerosol and Radiative Effects Study (CARES) govCampaignsCarbonaceous Aerosol and Radiative Effects Study (CARES) Campaign Links CARES Website Related Campaigns Carbonaceous Aerosol and Radiation Effects Study (CARES) - Surface Meteorological Sounding 2010.05.26, Zaveri, OSC Carbonaceous Aerosol and Radiation Effects Study (CARES) Photo-Acoustic Aerosol Light Absorption and Scattering 2010.05.26, Arnott, OSC Carbonaceous Aerosol and Radiative Effects Study (CARES): SMPS & CCN counter deployment during CARES/Cal-NEx 2010.05.04, Wang, OSC Carbonaceous Aerosol and Radiative Effects Study (CARES) Ground Based Instruments 2010.04.01, Cziczo, OSC Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Carbonaceous Aerosol and Radiative Effects Study (CARES)

220

Distinguishing Aerosol Impacts on Climate over the Past Century  

Science Journals Connector (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 ...

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

2009-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol chemical speciation" 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.


221

Atmospheric Aerosol Optical Properties in the Persian Gulf  

Science Journals Connector (OSTI)

Aerosol optical depth measurements over Bahrain acquired through the ground-based Aerosol Robotic Network (AERONET) are analyzed. Optical depths obtained from ground-based sun/sky radiometers showed a pronounced temporal trend, with a maximum ...

Alexander Smirnov; Brent N. Holben; Oleg Dubovik; Norm T. O'Neill; Thomas F. Eck; Douglas L. Westphal; Andreas K. Goroch; Christophe Pietras; Ilya Slutsker

2002-02-01T23:59:59.000Z

222

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

SciTech Connect

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

223

Emission-Induced Nonlinearities in the Global Aerosol System: Results from the ECHAM5-HAM Aerosol-Climate Model  

Science Journals Connector (OSTI)

In a series of simulations with the global ECHAM5-HAM aerosol-climate model, the response to changes in anthropogenic emissions is analyzed. Traditionally, additivity is assumed in the assessment of the aerosol climate impact, as the underlying ...

Philip Stier; Johann Feichter; Silvia Kloster; Elisabetta Vignati; Julian Wilson

2006-08-01T23:59:59.000Z

224

Toward a Minimal Representation of Aerosols in Climate Models: Comparative Decomposition of Aerosol Direct, Semidirect, and Indirect Radiative Forcing  

Science Journals Connector (OSTI)

The authors have decomposed the anthropogenic aerosol radiative forcing into direct contributions from each aerosol species to the planetary energy balance through absorption and scattering of solar radiation, indirect effects of anthropogenic ...

S. J. Ghan; X. Liu; R. C. Easter; R. Zaveri; P. J. Rasch; J.-H. Yoon; B. Eaton

2012-10-01T23:59:59.000Z

225

Nonequilibrium atmospheric secondary organic aerosol formation and growth  

Science Journals Connector (OSTI)

...Mexico City area are shown...inorganic atmospheric aerosols...2005 ) A large organic aerosol source...photochemical and thermal studies of...Characteristic Group Frequencies—Tables and...particle thermal speed...phase-equilibrium in the atmospheric system: Aerosol...Support, Non-U.S...Determination by plasma-based...implications for atmospheric chemistry...2002) A thermal disso-ciation...

Véronique Perraud; Emily A. Bruns; Michael J. Ezell; Stanley N. Johnson; Yong Yu; M. Lizabeth Alexander; Alla Zelenyuk; Dan Imre; Wayne L. Chang; Donald Dabdub; James F. Pankow; Barbara J. Finlayson-Pitts

2012-01-01T23:59:59.000Z

226

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

227

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.

228

DO AEROSOLS CHANGE CLOUD COVER AND AFFECT CLIMATE?  

E-Print Network (OSTI)

AS SEEN FROM SPACE Fire plumes from southern Mexico transported north into Gulf of Mexico. #12;CLOUD IPCC AR4 (2007) 3210-1-2 Forcing, W m-2 CO2 CH4 CFCs N2O Long Lived Greenhouse Gases Tropospheric;AEROSOL INFLUENCES ON CLIMATE AND CLIMATE CHANGE #12;DMS #12;AEROSOL IN MEXICO CITY BASIN #12;AEROSOL

Schwartz, Stephen E.

229

Indirect and Semi-Direct Aerosol Campaign  

NLE Websites -- All DOE Office Websites (Extended Search)

Campaign Campaign For the month of April, researchers are descending on and above Barrow, Alaska, to obtain data from the atmosphere that will help them understand the impacts that aerosols have on Arctic clouds and climate. Scientists sponsored by the U.S. Department of Energy's Atmospheric Radiation Measurement (ARM) Climate Research Facility are using a heavily instrumented aircraft to collect data from the sky, while instruments based at surface sites in Barrow and Atqasuk, Alaska, are obtaining measurements from the ground. Information obtained during the Indirect and Semi-Direct Aerosol Campaign, or ISDAC, will help scientists analyze the role of aerosols in climate, and represents a key contribution to Arctic climate research during International Polar Year.

230

Researchers Model Impact of Aerosols Over California  

NLE Websites -- All DOE Office Websites (Extended Search)

Researchers Model Researchers Model Impact of Aerosols Over California Researchers Model Impact of Aerosols Over California Research may clarify the effectiveness of regional pollution controls May 28, 2013 | Tags: Climate Research, Hopper Contact: Linda Vu, lvu@lbl.gov, (510) 495-2404 LosAngelesSmogv1.jpg Smog over downtown Los Angeles. Aerosols are microscopic particles-like dust, pollen and soot-that ubiquitously float around in our atmosphere. Despite their tiny stature, these particles can have a huge impact on human health, climate and the environment. So scientists from the Pacific Northwest National Laboratory (PNNL), Colorado State University and the California Air Resources Board have set out to characterize the roles of various particles as atmospheric change agents on a regional scale.

231

Characterizing the formation of secondary organic aerosols  

SciTech Connect

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

232

Recent speciation of Capsella rubella from Capsella grandiflora, associated with loss of  

E-Print Network (OSTI)

Recent speciation of Capsella rubella from Capsella grandiflora, associated with loss of self-incompatibility) Flowering plants often prevent selfing through mechanisms of self-incompatibility (S.I.). The loss of S of closely related diploid species, the self-incompatible Capsella grandiflora and the self

Weigel, Detlef

233

Artificial neural networks in models of specialisation, guild evolution and sympatric speciation  

E-Print Network (OSTI)

11 Artificial neural networks in models of specialisation, guild evolution and sympatric speciation 1/12/10 6:05:26pm page 236 Modelling Perception in Artificial Neural Networks, ed. C. R. Tosh and G artificial neural networks as models for the plant recognition mechanism in insects (Holmgren & Getz,

Getz, Wayne M.

234

Kinetic effects of temperature on rates of genetic divergence and speciation  

E-Print Network (OSTI)

in speciation rates caused by some independent variable, such as earth surface area or solar energy input (5; and ¶Department of Biology, University of New Mexico, Albuquerque, NM 87131 Contributed by James H. Brown, May 2 understood. We derive a model that quantifies the role of kinetic energy in generating biodiver- sity

Brown, James H.

235

In-situ metal speciation in soils using synchrotron based techniques David McNear1  

E-Print Network (OSTI)

become phytotoxic. In the topsoil around former Zn smelters and on sewage sludge sites, weight percent on the application of !-EXAS and !-SXRF techniques at beamline 10.3.2 to investigate the speciation of zinc (Zn were obtained from a former zinc smelter (Belgium), where 135 ha of land were heavily contaminated

Sparks, Donald L.

236

Speciation of heavy metals in cement-stabilized waste forms: A micro-spectroscopic study  

E-Print Network (OSTI)

Assuring safe disposal and long-term storage of haz- ardous and radioactive wastes represents a primary en- vironmental task of industrial societies. The long-term disposal of the hazardous wastes is associatedSpeciation of heavy metals in cement-stabilized waste forms: A micro-spectroscopic study M. Vespa

237

Speciation of adsorbed yttrium and rare earth elements on oxide surfaces  

E-Print Network (OSTI)

Speciation of adsorbed yttrium and rare earth elements on oxide surfaces Wojciech Piasecki, Dimitri 10 June 2008 Abstract The distribution of yttrium and the rare earth elements (YREE) between natural investigate the applicability of the X-ray results to rare earth elements and to several oxides in addition

Sverjensky, Dimitri A.

238

Assessing the effect of metal speciation on lead toxicity to Vicia faba pigment contents  

Science Journals Connector (OSTI)

Abstract Lead is a highly toxic heavy metal, but its putative toxicity with respect to its speciation remains to unveil. In this study, Pb-induced toxicity to Vicia faba pigment contents was assessed against Pb speciation and accumulation. After a culture period of three weeks, V. faba seedlings were exposed to 5 ?M of lead nitrate alone or chelated by citric acid (CA) or ethylenediaminetetraacetic acid (EDTA). The plants were treated for 1, 4, 8, 12 and 24 h in nutrient solution. Exposure to Pb-5 caused increased production of reactive oxygen species, lipid peroxidation and decrease in V. faba chlorophyll contents during 24 h. Lead-induced oxidative stress and toxicity to chlorophyll contents varied with the speciation of Pb. Addition of EDTA to Pb solution alleviated Pb-induced oxidative stress and toxicity to V. faba pigments by decreasing Pb accumulation in V. faba leaves. However, addition of citric acid to Pb did not affect Pb accumulation or toxicity to V. faba leaves. It is proposed that metal speciation plays an important role in Pb toxicity to V. faba pigment. Moreover, organic ligands vary greatly in terms of their ability to modify Pb phytoaccumulation and toxicity.

Muhammad Shahid; Camille Dumat; Bertrand Pourrut; Muhammad Sabir; Eric Pinelli

2014-01-01T23:59:59.000Z

239

A genomic view of introgression and hybrid speciation Eric J Baack1  

E-Print Network (OSTI)

A genomic view of introgression and hybrid speciation Eric J Baack1 and Loren H Rieseberg1,2 Hybridization in plants and animals is more common and has more complex outcomes than previously realized that a substantial fraction of their genomes are permeable to alleles from related species. Hybridization can lead

Rieseberg, Loren

240

Aerodynamic Focusing Of High-Density Aerosols  

SciTech Connect

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

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

Near real time vapor detection and enhancement using aerosol adsorption  

SciTech Connect

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

242

Technical Note: Estimating Aerosol Effects on Cloud Radiative Forcing  

SciTech Connect

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

243

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

244

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

245

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

246

A balloon-borne aerosol spectrometer for high altitude low aerosol concentration measurements  

SciTech Connect

Funded by Air Force Wright Aeronautical Laboratory, a new balloon-borne high altitude aerosol spectrometer, for the measurement of cirrus cloud ice crystals, has been developed and successfully flown by Sandia National Laboratories and Radiance Research. This report (1) details the aerosol spectrometer design and construction, (2) discusses data transmission and decoding, (3) presents data collected on three Florida flights in tables and plots. 2 refs., 11 figs., 3 tabs.

Brown, G.S. (Sandia National Labs., Albuquerque, NM (USA)); Weiss, R.E. (Radiance Research, Seattle, WA (USA))

1990-08-01T23:59:59.000Z

247

Understanding Brown Carbon Aerosols and Their Role in Climate Change  

NLE Websites -- All DOE Office Websites (Extended Search)

Brown Carbon Aerosols Brown Carbon Aerosols Tiny aerosol particles in the atmosphere are a possible cause of climate change. Among the many contributors to climate change are aerosols in the atmosphere. These tiny particles suspended in the air come from many sources, some natural and some man-made. Some aerosols are organic (containing carbon), while others are inorganic (such as sea salt and sulfates). Most aerosols reflect sunlight, and some also absorb it. Many of these nanoparticles have severe health effects in addition to climate effects. Human activities that produce aerosols include transportation, industry, and agriculture. Black carbon particles (a component of soot) originating from combustion processes have been known for some time to absorb sunlight and warm the

248

Response of California temperature to regional anthropogenic aerosol  

NLE Websites -- All DOE Office Websites (Extended Search)

Response of California temperature to regional anthropogenic aerosol Response of California temperature to regional anthropogenic aerosol changes Title Response of California temperature to regional anthropogenic aerosol changes Publication Type Journal Article Year of Publication 2008 Authors Novakov, Tihomir, Thomas W. Kirchstetter, Surabi Menon, and Jeffery Aguiar Journal Geophysical Research Letters Volume 35 Issue 19 Abstract In this paper, we compare constructed records of concentrations of black carbon (BC) - an indicator of anthropogenic aerosols - with observed surface temperature trends in California. Annual average BC concentrations in major air basins in California significantly decreased after about 1990, coincident with an observed statewide surface temperature increase. Seasonal aerosol concentration trends are consistent with observed seasonal temperature trends. These data suggest that the reduction in anthropogenic aerosol concentrations contributed to the observed surface temperature increase. Conversely, high aerosol concentrations may lower surface temperature and partially offset the temperature increase of greenhouse gases.

249

LABORATORY REPORT ON IODINE ({sup 129}I AND {sup 127}I) SPECIATION, TRANSFORMATION AND MOBILITY IN HANFORD GROUNDWATER, SUSPENDED PARTICLES AND SEDIMENTS  

SciTech Connect

The Hanford Site in eastern Washington produced plutonium for several decades and in the process generated billions of gallons of radioactive waste. Included in this complex mixture of waste was 50 Ci of iodine-129 ({sup 129}I). Iodine-129’s high abundance, due to its high fission yield, and extreme toxicity result in iodine-129 becoming a key risk driver at many Department of Energy (DOE) sites. The mobility of radioiodine in arid environments, such as the Hanford Site, depends largely on its chemical speciation and is also greatly affected by many other environmental factors, especially natural sediment organic matter (SOM). Groundwater radioiodine speciation has not been measured in arid regions with major plumes or large disposed {sup 129}I inventories, including the Hanford Site, Idaho National Laboratory, and Nevada Test Site. In this study, stable iodine-127 and radioiodine-129 speciation, pH, and dissolved organic carbon (DOC) of groundwater samples collected from seven wells located in the 200-West Area of the Hanford site were investigated. The most striking finding was that iodate (IO{sub 3}{sup -}) was the most abundant species. Unexpectedly, iodide (I{sup -}), which was likely the form of iodine in the source materials and the expected dominant groundwater species based on thermodynamic considerations, only accounted for 1-2% of the total iodine concentration. It is likely that the relatively high pH and the low abundance of sedimentary organic matter (SOM) that is present at the site slowed down or even inhibited the reduction of iodate, as SOM abiotically reduce iodate into iodide. Moreover, a study on the kinetics of iodide and iodate uptake and aqueous speciation transformation by three representative subsurface Hanford sediments was performed over a period of about one month. This study was carried out by using iodide-125 or iodate-125 at the ambient iodine-127concentration found at the site. Iodate K{sub d} values were on average 89% greater than iodide K{sub d} values, and the K{sub d} values for both species tended to increase with the amount of organic carbon (OC) present in the sediment. It is especially noteworthy that this trend existed at the very low OC concentrations that naturally exist in the Hanford sediments. Iodine and OC can form essentially irreversible covalent bonds, thereby providing a yet unstudied {sup 129}I retardation reaction at the Hanford Site. In addition to the transformation of iodine species, the sediment collected from the vadose zone also released stable iodide into the aqueous phase. It was found that the three sediments all took up the ambient iodate from the groundwater and slowly transformed it into iodide under the laboratory conditions, likely dependent on the abundance of reducing agents such as organic matter and Fe{sup 2+}. Therefore two competitive iodine processes were identified, the tendency for the sediment to reduce iodate to iodide, and the groundwater chemistry to maintain the iodine as iodate, presumably it is largely the result of natural pH and dissolved O{sub 2}/Eh levels. Suspended carbonate (and silica) particles collected from Hanford groundwater contained elevated amounts of iodine (142 ± 8 ?g/g iodine), consisting mainly of iodate (>99%). Iodate was likely incorporated into the carbonate structure during calcite precipitation upon degasing of CO{sub 2} as the groundwater samples were removed from the subsurface. This concentration of groundwater iodate in precipitated carbonate has implication to long-term fate and transport of 129I and on active in-situ {sup 129}I groundwater remediation. This study provides some of the first groundwater radioiodine speciation studies conducted in arid environments and provides much needed mechanistic descriptions to permit making informed decisions about low-cost/high intellectual input remediation options, such as monitored natural attenuation, or long-term stewardship of nuclear waste disposal sites.

Kaplan, D.; Santschi, P.; Xu, C.; Zhang, S.; Ho, Y.; Li, H.; Schwehr, K.

2012-09-30T23:59:59.000Z

250

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

SciTech Connect

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

251

Detailed chemical characterization of unresolved complex mixtures in  

NLE Websites -- All DOE Office Websites (Extended Search)

Detailed chemical characterization of unresolved complex mixtures in Detailed chemical characterization of unresolved complex mixtures in atmospheric organics: Insights into emission sources, atmospheric processing, and secondary organic aerosol formation Title Detailed chemical characterization of unresolved complex mixtures in atmospheric organics: Insights into emission sources, atmospheric processing, and secondary organic aerosol formation Publication Type Journal Article Year of Publication 2013 Authors Chan, Arthur W. H., Gabriel Isaacman, Kevin R. Wilson, David R. Worton, Christopher R. Ruehl, Theodora Nah, Drew R. Gentner, Timothy R. Dallmann, Thomas W. Kirchstetter, Robert A. Harley, Jessica B. Gilman, William C. Kuster, Joost A. de Gouw, John H. Offenberg, Tadeusz E. Kleindienst, Ying H. Lin, Caitlin L. Rubitschun, Jason D. Surratt, Patrick L. Hayes, Jose L. Jimenez, and Allen H. Goldstein

252

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

253

Photophoretic levitation of engineered aerosols for geoengineering  

Science Journals Connector (OSTI)

...W. Keith Energy and Environmental...space-based solar scattering...The salient advantage of sulfate aerosols...instrument. Disadvantages of sulfates...concentrating solar power systems...higher energy than molecules...solving the energy balance equation...ratio of solar-spectrum to thermal-spectrum...two of the disadvantages of stratospheric...

David W. Keith

2010-01-01T23:59:59.000Z

254

Modeling Semivolatile Organic Aerosol Mass Emissions from  

E-Print Network (OSTI)

in diluted diesel and wood combustion exhaust are interpreted using a two-component absorptive with dilution of both wood smoke and diesel exhaust can be described by two lumped compounds in roughly equal. Introduction Sources of organic aerosol such as diesel engines and wood stoves emit semivolatile organic

Stanier, Charlie

255

ADEPT. aerosol deposition in cylindrical pipes  

SciTech Connect

ADEPT calculates the deposition of aerosols in straight cylindrical pipes during turbulent air flow. Aerosol deposition is calculated in a time-dependent manner based on empirical correlations for turbulent flow in pipes. The calculated deposition during a single time interval is cumulative with that of previous time intervals and results in a decreasing inner diameter of the pipe. The calculated deposition is assumed uniform over the length of the pipe. The entering aerosol distribution is specified by the user in the form of a log-normal distribution of accumulated mass versus particle size and may be time dependent. Entering flow conditions are also specified by the user and may also be time dependent. For simplicity and generality, the geometry implicit in the program is that of a cylindrical pipe with no bends or fittings. The flow is turbulent and monodirectional; only one set of inlet conditions may be applied at a given time. The flow parameters are not calculated along the length of pipe; therefore, the dynamic behavior of the aerosol within the pipe as well as the effects of reentrainment cannot be determined explicitly. A typical problem requires 2 minutes of CPU time.

Fazekas, P.; Tewarson, S.C (Burns and Roe, Oradell, NJ (United States))

1985-01-01T23:59:59.000Z

256

ADEPT. Aerosol Deposition in Cylindrical Pipes  

SciTech Connect

ADEPT calculates the deposition of aerosols in straight cylindrical pipes during turbulent air flow. Aerosol deposition is calculated in a time-dependent manner based on empirical correlations for turbulent flow in pipes. The calculated deposition during a single time interval is cumulative with that of previous time intervals and results in a decreasing inner diameter of the pipe. The calculated deposition is assumed uniform over the length of the pipe. The entering aerosol distribution is specified by the user in the form of a log-normal distribution of accumulated mass versus particle size and may be time dependent. Entering flow conditions are also specified by the user and may also be time dependent. For simplicity and generality, the geometry implicit in the program is that of a cylindrical pipe with no bends or fittings. The flow is turbulent and monodirectional; only one set of inlet conditions may be applied at a given time. The flow parameters are not calculated along the length of pipe; therefore, the dynamic behavior of the aerosol within the pipe as well as the effects of reentrainment cannot be determined explicitly. A typical problem requires 2 minutes of CPU time.

Fazekas, P.; Tewarson, S.C [Burns and Roe, Oradell, NJ (United States)

1985-01-01T23:59:59.000Z

257

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

258

Does species diversity really drive speciation? Henrique M. Pereira, Va^nia M. Proenca and Luis Vicente  

E-Print Network (OSTI)

Does species diversity really drive speciation? Henrique M. Pereira, Va^nia M. Proenc¸a and Luis Vicente H. M. Pereira (hpereira@stanfordalumni.org), CEHIDRO, Dept Civil Engineering, Inst. Superior Te

Pereira, Henrique Miguel

259

Effect of Bromide Ion on Haloacetic Acid Speciation Resulting from Chlorination and Chloramination of Aquatic Humic Substances  

Science Journals Connector (OSTI)

In addition to studying the effect of bromide ion on HAA speciation, this work included investigation of the effect of pH on HAA formation and speciation, comparison of the effect of chlorination and chloramination on HAA formation and speciation, and comparison of two different sources of natural organic material with respect to HAA formation and speciation. ... The ether layer was separated and derivatized with diazomethane, and the samples were then analyzed on an HP-5890 Series II gas chromatograph with electron capture detector (Hewlett-Packard, San Fernando, CA). ... The results of these analyses are given in Table 1 for finished waters from the Philadelphia (PA) Suburban Water Co. (PSWC), the Metropolitan Water District of Southern California (MWD), and the cities of Houston, TX, and Corpus Christi, TX. ...

Gretchen A. Cowman; Philip C. Singer

1995-12-27T23:59:59.000Z

260

Direct and semidirect aerosol effects of Southern African biomass burning aerosol  

SciTech Connect

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

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

UNDERSTANDING THE INFLUENCES OF ATMOSPHERIC AEROSOLS ON CLIMATE AND CLIMATE CHANGE  

E-Print Network (OSTI)

.ecd.bnl.gov/steve BOB BRAWDY / AP #12;OVERVIEW Aerosol influences on climate and climate change Earth's energy balance remarks #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 AS SEEN FROM SPACE Fire plumes from southern

Schwartz, Stephen E.

262

CHEMICAL MARKETING  

Science Journals Connector (OSTI)

CHEMICAL MARKETING ... The reason, I believe, is that the chemical industry has been blind (until very recently) to the need for paying attention to marketing. ... Its marketing needs are now like those of a mature—no longer a growing—industry. ...

1960-12-19T23:59:59.000Z

263

Inter-annual Tropospheric Aerosol Variability in Late Twentieth Century and its Impact on Tropical Atlantic and West African Climate by Direct and Semi-direct Effects  

SciTech Connect

A new high-resolution (0.9$^{\\circ}$x1.25$^{\\circ}$ in the horizontal) global tropospheric aerosol dataset with monthly resolution is generated using the finite-volume configuration of Community Atmosphere Model (CAM4) coupled to a bulk aerosol model and forced with recent estimates of surface emissions for the latter part of twentieth century. The surface emissions dataset is constructed from Coupled Model Inter-comparison Project (CMIP5) decadal-resolution surface emissions dataset to include REanalysis of TROpospheric chemical composition (RETRO) wildfire monthly emissions dataset. Experiments forced with the new tropospheric aerosol dataset and conducted using the spectral configuration of CAM4 with a T85 truncation (1.4$^{\\circ}$x1.4$^{\\circ}$) with prescribed twentieth century observed sea surface temperature, sea-ice and greenhouse gases reveal that variations in tropospheric aerosol levels can induce significant regional climate variability on the inter-annual timescales. Regression analyses over tropical Atlantic and Africa reveal that increasing dust aerosols can cool the North African landmass and shift convection southwards from West Africa into the Gulf of Guinea in the spring season in the simulations. Further, we find that increasing carbonaceous aerosols emanating from the southwestern African savannas can cool the region significantly and increase the marine stratocumulus cloud cover over the southeast tropical Atlantic ocean by aerosol-induced diabatic heating of the free troposphere above the low clouds. Experiments conducted with CAM4 coupled to a slab ocean model suggest that present day aerosols can shift the ITCZ southwards over the tropical Atlantic and can reduce the ocean mixed layer temperature beneath the increased marine stratocumulus clouds in the southeastern tropical Atlantic.

Evans, Katherine J [ORNL; Hack, James J [ORNL; Truesdale, John [National Center for Atmospheric Research (NCAR); Mahajan, Salil [ORNL; Lamarque, J-F [University Center for Atmospheric Research

2012-01-01T23:59:59.000Z

264

Direct Surface Analysis of Time-Resolved Aerosol Impactor Samples with Ultrahigh-Resolution Mass Spectrometry  

E-Print Network (OSTI)

.; Pan, Y.; Mitloehner, F. M. Atmos. Environ. 2012, Submitted. (21) Lundgren, D. A. Journal of the Air Pollution Control Association 1967, 17, 225-9. (22) Schultz, G. A.; Corso, T. N.; Prosser, S. J.; Zhang, S. Anal. Chem. 2000, 72, 4058-4063. 19... in negative health effects caused by air pollution and are linked to increases in respiratory and cardio-vascular diseases2,3. All these particle effects are influenced by the chemical composition of the aerosol particles. A major fraction, often more than 50...

Fuller, Stephen J.; Zhao, Yongjing; Cliff, Steven S.; Wexler, Anthony S.; Kalberer, Markus

2012-10-18T23:59:59.000Z

265

Aerosol Mass Spectrometry via Laser-Induced Incandescence Particle Vaporization Final Report  

SciTech Connect

We have successfully developed and commercialized a soot particle aerosol mass spectrometer (SP-AMS) instrument to measure mass, size, and chemical information of soot particles in ambient environments. The SP-AMS instrument has been calibrated and extensively tested in the laboratory and during initial field studies. The first instrument paper describing the SP-AMS has been submitted for publication in a peer reviewed journal and there are several related papers covering initial field studies and laboratory studies that are in preparation. We have currently sold 5 SP-AMS instruments (either as complete systems or as SP modules to existing AMS instrument operators).

Timothy B. Onasch

2011-10-20T23:59:59.000Z

266

Aerosol Modeling at LLNL - Our capability, results, and perspective  

NLE Websites -- All DOE Office Websites (Extended Search)

Aerosol Indirect Effects to Cloud Aerosol Indirect Effects to Cloud Parameterizations in Short-Range Weather Forecasts with CAM3 Over the Southern Great Plains during May 2003 IOP Lawrence Livermore National Laboratory This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344 Catherine Chuang, James Boyle Shaocheng Xie and James Kelly LLNL-POST-401948 March 11, 2008 Why are aerosol/cloud interactions important? The greatest uncertainty in the assessment of radiative forcing arises from the interactions of aerosols with clouds. Radiative forcing of climate between 1750 and 2005 (IPCC, 2007) Sources of uncertainty Emissions Gas to particle conversion Aerosol size distribution Linkage between aerosols

267

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

NLE Websites -- All DOE Office Websites (Extended Search)

7 Cumulus Humilis Aerosol Process Study (CHAPS) 7 Cumulus Humilis Aerosol Process Study (CHAPS) Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : 2007 Cumulus Humilis Aerosol Process Study (CHAPS) 2007.06.04 - 2007.06.25 Lead Scientist : Carl Berkowitz For data sets, see below. Description The primary goal of this campaign was to characterize and contrast freshly emitted aerosols above, within and below fields of cumulus humilis (or fair-weather cumulus, FWC) and to use these observations to address how below-cloud and above-cloud aerosol optical and cloud nucleating properties differ downwind of a mid-size city relative to similar aerosols in air less affected by emissions. The observations from this campaign can also be used to aid in the development and evaluation of parameterizations of the

268

AEROgui: A graphical user interface for the optical properties of aerosols  

Science Journals Connector (OSTI)

Atmospheric aerosols have an uncertain effect on climate, and serious impact on human health. The uncertainty in the aerosols role on climate has several sources. First, aerosols present a great spatial and temporal variability. The spatial variability ...

R. Pedrós; J.L. Gómez-Amo; C.R. Marcos; M.P. Utrillas; S. Gandía; F. Tena; J.A. Martinez Lozano

269

Tropospheric Aerosol Optical Thickness from the GOCART Model and Comparisons with Satellite and Sun Photometer Measurements  

Science Journals Connector (OSTI)

The Georgia Institute of Technology–Goddard Global Ozone Chemistry Aerosol Radiation and Transport (GOCART) model is used to simulate the aerosol optical thickness ? for major types of tropospheric aerosols including sulfate, dust, organic carbon ...

Mian Chin; Paul Ginoux; Stefan Kinne; Omar Torres; Brent N. Holben; Bryan N. Duncan; Randall V. Martin; Jennifer A. Logan; Akiko Higurashi; Teruyuki Nakajima

2002-02-01T23:59:59.000Z

270

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

271

Aerosol climate effects and air quality impacts from 1980 to 2030  

E-Print Network (OSTI)

Aerosol climate e?ects and air quality impacts from 1980 toAerosol climate e?ects and air quality impacts from 1980 toAerosol climate e?ects and air quality impacts from 1980 to

Menon, Surabi

2008-01-01T23:59:59.000Z

272

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.

273

Speciation within bonneted bats (genus Eumops): The complexity of morphological, mitochondrial, and nuclear datasets in systematics  

E-Print Network (OSTI)

SPECIATION WITHIN BONNETED BATS (GENUS EUMOPS): THE COMPLEXITY OF MORPHOLOGICAL, MITOCHONDRIAL, AND NUCLEAR DATA SETS IN SYSTEMATICS MOLLY M. MCDONOUGH,* LOREN K. AMMERMAN,ROBERT M. TIMM,HUGH H. GENOWAYS, PETER A. LARSEN, AND ROBERT J. BAKER... rates of genetic markers, and nuclear–mitochondrial translocations have the potential to create disparity among data sets (Avise 1994; Cathey et al. 1998; Triant and DeWoody 2007). A critically evaluated, holistic approach to resolving phylogenetic...

McDonough, Molly M.; Ammerman, Loren K.; Timm, Robert M.; Genoways, Hugh H.; Larsen, Peter A.; Baker, Robert J.

2008-10-01T23:59:59.000Z

274

Aerosol and graphitic carbon content of snow  

SciTech Connect

Snow samples from southern New Mexico, west Texas, Antarctica, and Greenland were analyzed for aerosol and graphitic carbon. Graphitic carbon contents were found to be between 2.2 and 25 ..mu..g L/sup -1/ of snow meltwater; water-insoluble aerosol content varied between 0.62 and 8.5 mg L/sup -1/. For comparison, two samples of Camp Century, Greenland, ice core, having approximate ages of 4,000 and 6,000 years, were also analyzed. Ice core graphitic carbon contents were found to be 2.5 and 1.1 ..mu..g L/sup -1/. copyrightAmerican Geophysical Union 1987

Chy-acute-accentlek, P.; Srivastava, V.; Cahenzli, L.; Pinnick, R.G.; Dod, R.L.; Novakov, T.; Cook, T.L.; Hinds, B.D.

1987-08-20T23:59:59.000Z

275

Exploiting Diversity of Neural Ensembles with Speciated Evolution Seung-Ik Lee, Joon-Hyun Ahn, and Sung-Bae Cho  

E-Print Network (OSTI)

and is mod- ified using speciation technique. All fitnesses calculated, selection is conducted. Genetic operators, crossover and mutation, are applied to the selected individuals to produce next generation

Cho, Sung-Bae

276

Influence of plant species and phosphorus amendments on metal speciation and bioavailability in a smelter impacted soil: a case study of food-chain contamination  

Science Journals Connector (OSTI)

The present research aimed to assess the influence of two phosphorous (P) amendments on metal speciation in rhizosphere soil and the soil–plant transfer of metals.

Muhammad Shahid; Tiantian Xiong; Nasir Masood…

2014-04-01T23:59:59.000Z

277

Impact of solid fuel combustion technology on valence speciation of chromium in fly ash  

Science Journals Connector (OSTI)

Abstract Fly ash (FA) generated in real furnaces was used to evaluate the impact of the kind of the solid fuel burnt and combustion technology on chromium speciation, particularly the presence of Cr(III) and Cr(VI) forms as well as readily and hardly leachable chromium(VI) species in FAs. The \\{FAs\\} originated from a pulverized coal combustion boiler (PCC boiler), a fluidized bed combustion boiler (FBC boiler), a stoker-fired boiler (SF boiler), a municipal solid waste incinerator (MSWI), a cement rotary kiln (CRK) and a modern domestic boiler (DB). The speciation analysis of chromium was carried out by means of extraction followed by catalytic cathodic stripping voltammetry with adsorption of Cr(III)-DTPA complexes (CCSV-DTPA) for determination of Cr(VI) and AAS was used for determination of Cr content. It has been revealed that the antagonistic action of alkali metal compounds and iron oxides plays a crucial role in shaping valence speciation of chromium. According to the proposed transformation path of oxidation of Cr(III) to Cr(VI), hard coal combustion in an SF boiler, an FBC boiler or a domestic boiler will generate \\{FAs\\} with a low Cr(VI) level. Replacing fuel with biomass should create favorable conditions for generating FA enriched with Cr(VI). Relatively high concentrations of Cr(VI) can also be expected in FA generated in the process of high-temperature combustion of coal in PCC boilers.

Ryszard ?wietlik; Marzena Trojanowska; Monika ?o?y?ska; Artur Molik

2014-01-01T23:59:59.000Z

278

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

279

ARM AOS Processing Status and Aerosol Intensive Properties VAP  

NLE Websites -- All DOE Office Websites (Extended Search)

Andrews, and P. J. Sheridan National Oceanic and Atmospheric Administration Boulder, Colorado Abstract The Atmospheric Radiation Measurement (ARM) Aerosol Observing System (AOS)...

280

Method of Preparing Super-Concentrated Jets From Dense Aerosol...  

NLE Websites -- All DOE Office Websites (Extended Search)

Michael J. Hay, Ernest J. Valeo, and Nathaniel J. Fisch This is improvement in aerodynamic focusing of dilute aerosol suspensions. All previous work on this subject has...

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

ARM - Field Campaign - Pajarito Aerosol Coupling to Ecosystems...  

NLE Websites -- All DOE Office Websites (Extended Search)

properties during the winter-spring transition. Opportunity to investigate fire and automobile emission interactions with biogenic aerosols will also harnessed MAOS will be...

282

Heavy Duty Diesel Engine Exhaust Aerosol Particle and Ion Measurements  

Science Journals Connector (OSTI)

Heavy Duty Diesel Engine Exhaust Aerosol Particle and Ion Measurements ... diesel engines have received increasing attention due to their potential health effects. ...

Tero Lähde; Topi Rönkkö; Annele Virtanen; Tanja J. Schuck; Liisa Pirjola; Kaarle Hämeri; Markku Kulmala; Frank Arnold; Dieter Rothe; Jorma Keskinen

2008-12-09T23:59:59.000Z

283

Raman Lidar Measurements of Aerosols and Water Vapor During the...  

NLE Websites -- All DOE Office Websites (Extended Search)

modifications reduced but could not eliminate these adverse effects. The Raman lidar water vapor (aerosol extinction) measurements produced by these modified algorithms were,...

284

aerosol influenza transmission: Topics by E-print Network  

NLE Websites -- All DOE Office Websites (Extended Search)

and Information Sciences Websites Summary: . In preliminary work, we used artificial neural networks (ANNs) to construct global aerosol predictors by learningIntegration...

285

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

NLE Websites -- All DOE Office Websites (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...

286

E-Print Network 3.0 - aerosol modeling decadal Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

Geosciences 8 Absorbing aerosols and pre-summer monsoon hydroclimate variability over the Indian subcontinent: The challenge in investigating links Summary: in the aerosol-monsoon...

287

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

NLE Websites -- All DOE Office Websites (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,...

288

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

NLE Websites -- All DOE Office Websites (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......

289

E-Print Network 3.0 - aerosol lung inhalation Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

aerosolized by means... is aerosolized upon inhalation by utilizing the ... Source: Groningen, Rijksuniversiteit - Centre for Ecological and Evolutionary Studies, Department of...

290

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

NLE Websites -- All DOE Office Websites (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...

291

E-Print Network 3.0 - aerosol code comparisons Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

and Ecology 4 Estimates of global radiative forcing derived from the GlobAEROSOL dataset Summary: -sky direct aerosol radiative forcing. The Edwards and Slingo (1996)...

292

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

293

E-Print Network 3.0 - aerosols harbor diverse Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

Cloud & Aerosol Process Group CSDESRLNOAA Presented at: NIST... Aerosol Metrology for Climate Workshop 15th March, 2011 12;Deposition Snow Darkens and Warms BC...

294

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

NLE Websites -- All DOE Office Websites (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...

295

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...

296

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

NLE Websites -- All DOE Office Websites (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 <>...

297

E-Print Network 3.0 - alkali sulfate aerosol Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

Aerosol Formation during... " and "Mechanism of Alkali Sulfate Aerosols Formation during Biomass Combustion" describe the development... the ... Source: Ris National Laboratory...

298

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

NLE Websites -- All DOE Office Websites (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...

299

Development of Aerosol Models for Radiative Flux Calculations at ARM Sites: Utility of Trajectory Clustering for Characterizing Aerosol Climatology  

NLE Websites -- All DOE Office Websites (Extended Search)

Development of Aerosol Models for Radiative Flux Development of Aerosol Models for Radiative Flux Calculations at ARM Sites: Utility of Trajectory Clustering for Characterizing Aerosol Climatology E. Andrews Cooperative Institute for Research in the Environment University of Colorado Boulder, Colorado E. Andrews, J. A. Ogren, P. J. Sheridan, and J. M. Harris Climate Monitoring and Diagnostics Laboratory National Oceanic and Atmospheric Administration Boulder, Colorado P. K. Quinn Pacific Marine Environmental Laboratory National Oceanic and Atmospheric Administration Seattle, Washington Abstract The uncertainties associated with assumptions of generic aerosol properties in radiative transfer codes are unknown, which means that these uncertainties are frequently invoked when models and

300

Towards controlling PCDD/F production in a multi-fuel fired BFB boiler using two sulfur addition strategies. Part III: Cu speciation in the fly ash  

Science Journals Connector (OSTI)

Abstract PCDD/F abatement strategies – sulfur pellet addition and peat co-combustion – were tested for a BFB boiler facility utilizing SRF-bark-sludge as fuel. In this paper chemical and physical analyses of electrostatic precipitator (ESP) fly ashes were used to explain the differences in the performance of these strategies. These analyses revealed a difference between the coarse and fine fly ashes collected in the ESP. Chemical analysis of the fine fly ashes revealed high concentration of easily volatilized elements while the SEM micrographs showed that fine ash are composed of clusters of spherical particles, thereby leading to a conclusion that fine ashes were originally in a gas phase in the high temperature zones of the boiler. Variation in the distribution of active and passive forms of Cu in fly ashes was revealed using X-ray absorption spectroscopy (XANES mode). It was also found that peat co-combustion led to increased formation of Cu oxides that may act as active catalysts in de novo synthesis. Furthermore, XANES revealed the formation of CuSO4 for all the test cases. By applying the empirical ratio between mole fractions of the active and passive species of Cu, the role of Cu speciation to PCDD/F production was emphasized. It is concluded that sulfur pellet addition is more effective than peat addition as a PCDD/F abatement strategy for the BFB facility understudy.

Cyril Jose E. Bajamundi; Pasi Vainikka; Irina Hyytiäinen; Kirsi Korpijärvi; Manu Lahtinen; Wantana Klysubun; Jukka Konttinen

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol chemical speciation" 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.


301

Characterization of atmospheric aerosols using Synchroton radiation total reflection X-ray fluorescence and Fe K-edge total reflection X-ray fluorescence-X-ray absorption near-edge structure  

Science Journals Connector (OSTI)

In this study a new procedure using Synchrotron total reflection X-ray fluorescence (SR-TXRF) to characterize elemental amounts in atmospheric aerosols down to particle sizes of 0.015 um is presented. The procedure was thoroughly evaluated regarding bounce off effects and blank values. Additionally the potential of total reflection X-ray fluorescence–X-ray absorption near edge structure (SR-TXRF-XANES) for speciation of FeII/III down to amounts of 34 pg in aerosols which were collected for 1 h is shown. The aerosols were collected in the city of Hamburg with a low pressure Berner impactor on Si carriers covered with silicone over time periods of 60 and 20 min each. The particles were collected in four and ten size fractions of 10.0–8.0 ?m, 8.0–2.0 ?m, 2.0–0.13 ?m 0.13–0.015 ?m (aerodynamic particle size) and 15–30 nm, 30–60 nm, 60–130 nm, 130–250 nm, 250–500 nm, 0.5–1 ?m, 1–2 ?m, 2–4 ?m, 4–8 ?m, 8–16 ?m. Prior to the sampling “bounce off” effects on Silicone and Vaseline coated Si carriers were studied with total reflection X-ray fluorescence. According to the results silicone coated carriers were chosen for the analysis. Additionally, blank levels originating from the sampling device and the calibration procedure were studied. Blank levels of Fe corresponded to 1–10% of Fe in the aerosol samples. Blank levels stemming from the internal standard were found to be negligible. The results from the Synchroton radiation total reflection X-ray fluorescence analysis of the aerosols showed that 20 min of sampling time gave still enough sample material for elemental determination of most elements. For the determination of the oxidation state of Fe in the aerosols different Fe salts were prepared as a reference from suspensions in isopropanol. The results from the Fe K-edge Synchroton radiation total reflection X-ray fluorescence-X-ray absorption near-edge structure analysis of the aerosol samples showed that mainly Fe(III) was present in all particle size fractions.

U.E.A. Fittschen; F. Meirer; C. Streli; P. Wobrauschek; J. Thiele; G. Falkenberg; G. Pepponi

2008-01-01T23:59:59.000Z

302

Basic research for assessment of geologic nuclear waste repositories: What solubility and speciation studies of transuranium elements can tell us  

SciTech Connect

Solubility and speciation data are important in understanding aqueous radionuclide transport through the geosphere. They define the source term for transport retardation processes such as sorption and colloid formation. Solubility and speciation data are useful in verifying the validity of geochemical codes that are part of predictive transport models. Results from solubility and speciation experiments of {sup 237}NpO{sub 2} {sup +}, {sup 239}Pu{sup 4+}, and {sup 241}Am{sup 3+}/Nd{sup 3+} in J-13 groundwater (from the Yucca Mountain region, Nevada, which is being investigated as a candidate high-level nuclear waste disposal site) at three different temperatures (25{degrees}, 60{degrees}, and 90{degrees}C) and pH values (6, 7, and 8.5) are presented and compared with published modeling calculations. The comparison results indicate that there is a great need for experimental data on the solubility and speciation of transuranium elements under a wide range of conditions, for example, pH, Eh, temperature, and composition of groundwaters. Additionally, the influence of alpha radiation and the radiolysis of the secondary transuranium solids on solubility and speciation should be studies. Solubility studies and model calculations should be extended to other important long-lived nuclear waste radionuclides such as nickel, zirconium, cadmium, radium, and thorium. 14 refs., 13 figs., 5 tabs.

Nitsche, H.

1990-12-01T23:59:59.000Z

303

Physicochemical Characterization of Capstone Depleted Uranium Aerosols I: Uranium Concentration in Aerosols as a Function of Time and Particle Size  

SciTech Connect

During the Capstone Depleted Uranium (DU) Aerosol Study, aerosols containing depleted uranium were produced inside unventilated armored vehicles (i.e., Abrams tanks and Bradley Fighting Vehicles) by perforation with large-caliber DU penetrators. These aerosols were collected and characterized, and the data were subsequently used to assess human health risks to personnel exposed to DU aerosols. The DU content of each aerosol sample was first quantified by radioanalytical methods, and selected samples, primarily those from the cyclone separator grit chambers, were analyzed radiochemically. Deposition occurred inside the vehicles as particles settled on interior surfaces. Settling rates of uranium from the aerosols were evaluated using filter cassette samples that collected aerosol as total mass over eight sequential time intervals. A moving filter was used to collect aerosol samples over time particularly within the first minute after the shot. The results demonstrate that the peak uranium concentration in the aerosol occurred in the first 10 s, and the concentration decreased in the Abrams tank shots to about 50% within 1 min and to less than 2% 30 min after perforation. In the Bradley vehicle, the initial (and maximum) uranium concentration was lower than those observed in the Abrams tank and decreased more slowly. Uranium mass concentrations in the aerosols as a function of particle size were evaluated using samples collected in the cyclone samplers, which collected aerosol continuously for 2 h post perforation. The percentages of uranium mass in the cyclone separator stages from the Abrams tank tests ranged from 38% to 72% and, in most cases, varied with particle size, typically with less uranium associated with the smaller particle sizes. Results with the Bradley vehicle ranged from 18% to 29% and were not specifically correlated with particle size.

Parkhurst, MaryAnn; Cheng, Yung-Sung; Kenoyer, Judson L.; Traub, Richard J.

2009-03-01T23:59:59.000Z

304

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

E-Print Network (OSTI)

, New Mexico, USA Michael Mishchenko Goddard Institute for Space Studies, NASA, New York, New York, USA between t = 0.1 and t = 0.8. The Department of Energy research satellite instrument, the Multispectral [Hobbs et al., 1997]. The aerosols' direct effect involves their interaction with solar and terrestrial

305

Chemical Occurrences  

Energy.gov (U.S. Department of Energy (DOE))

Classification of Chemical Occurrence Reports into the following four classes: Occurrences characterized by serious energy release, injury or exposure requiring medical treatment, or severe environmental damage, Occurrences characterized by minor injury or exposure, or reportable environmental release, Occurrences that were near misses including notable safety violations and Minor occurrences.

306

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

307

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

308

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

309

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

SciTech Connect

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

310

Determination of vertical profiles of aerosol extinction, single scatter  

NLE Websites -- All DOE Office Websites (Extended Search)

Determination of vertical profiles of aerosol extinction, single scatter Determination of vertical profiles of aerosol extinction, single scatter albedo and asymmetry parameter at Barrow. Sivaraman, Chitra Pacific Northwest National Laboratory Flynn, Connor Pacific Northwest National Laboratory Turner, David University of Wisconsin-Madison Category: Aerosols Efforts are currently underway to run and evaluate the Broadband Heating Rate Profile project at the ARM North Slope of Alaska (NSA) Barrow site for the time period March 2004 - February 2005. The Aerosol Best-Estimate (ABE) Value-Added Procedure (VAP) is to provide continuous estimates of vertical profiles of aerosol extinction, single-scatter albedo, and asymmetry parameter above the Northern Slopes of Alaska (NSA) facility. In the interest of temporal continuity, we have developed an algorithm that

311

ARM - Field Campaign - MArine Stratus Radiation Aerosol and Drizzle  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsMArine Stratus Radiation Aerosol and Drizzle (MASRAD) IOP govCampaignsMArine Stratus Radiation Aerosol and Drizzle (MASRAD) IOP Campaign Links Science Plan AMF Point Reyes Website AMF Point Reyes Data Plots Related Campaigns MASRAD: Pt. Reyes Stratus Cloud and Drizzle Study 2005.07.07, Coulter, AMF MASRAD: Cloud Condensate Nuclei Chemistry Measurements 2005.07.01, Berkowitz, AMF MASRAD - Aerosol Optical Properties 2005.06.29, Strawa, AMF MASRAD:Sub-Micron Aerosol Measurements 2005.06.20, Wang, AMF MASRAD: Cloud Study from the 2NFOV at Pt. Reyes Field Campaign 2005.06.02, Wiscombe, AMF Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : MArine Stratus Radiation Aerosol and Drizzle (MASRAD) IOP 2005.03.14 - 2005.09.14 Website : http://www.arm.gov/sites/amf/pye/ Lead Scientist : Mark Miller

312

Aerosol Retrievals under Partly Cloudy Conditions: Challenges and Perspectives  

SciTech Connect

There are lots of interesting and intriguing features of aerosols near clouds – many of which can be quite engaging, as well being useful and climate-related. Exploring aerosol with the aid of the remote sensing, in situ observations and numerical modeling has piqued our curiosity and led to improve insights into the nature of aerosol and clouds and their complex relationship. This chapter conveys the outstanding issues of cloudy-sky aerosol retrievals of important climate properties and outlines their fruitful connections to other research areas such as in situ measurements and model simulations. The chapter focuses mostly on treating the inverse problems in the context of the passive satellite remote sensing and how they can improve our understanding of the cloud-aerosol interactions. The presentation includes a basis in the inverse problem theory, reviews available approaches and discusses their applications to partly cloudy situations. Potential synergy of observations and model simulations is described as well.

Kassianov, Evgueni I.; Ovchinnikov, Mikhail; Berg, Larry K.; Flynn, Connor J.

2011-06-01T23:59:59.000Z

313

Do Diurnal Aerosol Changes Affect Daily Average Radiative Forcing?  

SciTech Connect

Strong diurnal variability of aerosol has been observed frequently for many urban/industrial regions. How this variability may alter the direct aerosol radiative forcing (DARF), however, is largely unknown. To quantify changes in the time-averaged DARF, we perform an assessment of 29 days of high temporal resolution ground-based data collected during the Two-Column Aerosol Project (TCAP) on Cape Cod, which is downwind of metropolitan areas. We demonstrate that strong diurnal changes of aerosol loading (about 20% on average) have a negligible impact on the 24-h average DARF, when daily averaged optical properties are used to find this quantity. However, when there is a sparse temporal sampling of aerosol properties, which may preclude the calculation of daily averaged optical properties, large errors (up to 100%) in the computed DARF may occur. We describe a simple way of reducing these errors, which suggests the minimal temporal sampling needed to accurately find the forcing.

Kassianov, Evgueni I.; Barnard, James C.; Pekour, Mikhail S.; Berg, Larry K.; Michalsky, Joseph J.; Lantz, K.; Hodges, G. B.

2013-06-17T23:59:59.000Z

314

Atmospheric aerosol monitoring at the Pierre Auger Observatory  

SciTech Connect

For a ground based cosmic-ray observatory the atmosphere is an integral part of the detector. Air fluorescence detectors (FDs) are particularly sensitive to the presence of aerosols in the atmosphere. These aerosols, consisting mainly of clouds and dust, can strongly affect the propagation of fluorescence and Cherenkov light from cosmic-ray induced extensive air showers. The Pierre Auger Observatory has a comprehensive program to monitor the aerosols within the atmospheric volume of the detector. In this paper the aerosol parameters that affect FD reconstruction will be discussed. The aerosol monitoring systems that have been deployed at the Pierre Auger Observatory will be briefly described along with some measurements from these systems.

Cester, R.; Chiosso, M.; Chirin, J.; Clay, R.; Dawson, B.; Fick, B.; Filipcic, A.; Garcia, B.; Grillo, A.; Horvat, M.; Iarlori, M.; Malek, M.; Matthews, J.; Matthews,; Melo, D.; Meyhandan, R.; Mostafa, M.; Mussa, R.; Prouza, M.; Raefert, B.; Rizi, V.

2005-07-01T23:59:59.000Z

315

Experiments related to the resuspension of aerosols during hydrogen burns  

SciTech Connect

We have performed seven ''add-on'' experiments in two large combustion facilities to investigate the capability of hydrogen burns to remove simulated structural and fission product aerosols previously deposited on small metal discs that have surfaces prototypical of those found in nuclear reactor containments. Our results suggest that hydrogen combustion provides an especially effective mechanism for removal (and, presumably, resuspension) of sedimented aerosols produced in a hypothetical nuclear reactor core-degradation or core-melting accident. The presence of condensing steam does not seem to assure adhesion of sedimented aerosols during hydrogen burns. Differences are exhibited between different surfaces as well as between types of aerosol. In-depth studies will be required to assess the impact exposure of sedimented aerosols to hydrogen burns might have on the radiological source term.

Nelson, L.S.; Guay, K.P.

1987-01-01T23:59:59.000Z

316

Colorimetric Au Nanoparticle Probe for Speciation Test of Arsenite and Arsenate Inspired by Selective Interaction between Phosphonium Ionic Liquid and Arsenite  

Science Journals Connector (OSTI)

Colorimetric Au Nanoparticle Probe for Speciation Test of Arsenite and Arsenate Inspired by Selective Interaction between Phosphonium Ionic Liquid and Arsenite ... With the colorimetric probe, we developed a protocol for naked eye speciation test of AsIII and AsV at levels below the World Health Organization (WHO) guideline of 10 µg L?1. ...

Zhiqiang Tan; Jingfu Liu; Yongguang Yin; Qiantao Shi; Chuanyong Jing; Guibin Jiang

2014-10-21T23:59:59.000Z

317

Optimization of aerosol penetration through transport lines  

E-Print Network (OSTI)

, F is the numerical reading from the fluorometer , L is the liquid volume of the measured (23) solution, 8 is the testing time for each filter, and V is the filter flow rate during the sample period. Penetration, P, of aerosol through... defined maxima on the penetration versus Reynolds number (or flow rate, since the diameter is constant for a given tube) curves for each tube size. Also, in order to observe an optimum tube diameter , a (10) fixed flow rate of 86 L/min was tested for a...

Wong Luque, Fermin Samuel

2012-06-07T23:59:59.000Z

318

A shrouded probe aerosol sampling cyclone  

E-Print Network (OSTI)

the air stream. In the present design, three concentric shrouds and a probe will be attached to the entrance of the cyclone. The shroud concept was first used in an aircraft-horne sampling device for collecting tropospheric aerosol particles... by A. R. McFarland and S. A. Batterman. College Station, Texas: 1989. 5. Strauss, W. and S. J. Nainwaring: Air Pollution. London, Baltimore, Maryland: Edward Arnold, 1984. pp. 95-96. 6. Moore, N. E. , and A. R. NcFarland: Stairmand-Type Sampling...

Little, Stewart Craig

2012-06-07T23:59:59.000Z

319

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

SciTech Connect

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

320

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

E-Print Network (OSTI)

;Carnegie Mellon University Smog Chamber Air supply Computer Temperature control Clean air 10 m3 Teflon spectrometer Aerosol mass spectrometerOzone monitor Air supply Computer Temperature control Clean air 10 m3 on temperature Hevap also needed Assumes no interactions among organic aerosol species or with inorganics. #12

Einat, Aharonov

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

Beryllium Carcinogenesis. I. Inhalation Exposure of Rats to Beryllium Sulfate Aerosol  

Science Journals Connector (OSTI)

...aerosol at a mean atmospheric concentration of...aerosol at a mean atmospheric concentration of...in the drinking water) for 2 weeks...a glass aerosol generator, with an airflow...chamber, distilled water was disseminated...aerosol generation, atmospheric concentration control...

Andrew L. Reeves; Daniel Deitch; and Arthur J. Vorwald

1967-03-01T23:59:59.000Z

322

Improving aerosol distributions below clouds by assimilating satellite-retrieved cloud droplet number  

Science Journals Connector (OSTI)

...remainder of the map to the...distributions for mass, number, composition...such as vertical velocity and aerosol composition...updated aerosol mass for each compound...aerosols in trade wind cumulus observed by...spectrum of updraft velocities and the internally...Starting from aerosol mass (M) and number...

Pablo E. Saide; Gregory R. Carmichael; Scott N. Spak; Patrick Minnis; J. Kirk Ayers

2012-01-01T23:59:59.000Z

323

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.

324

Influence of uranyl speciation and iron oxides on uranium biogeochemical redox reactions  

SciTech Connect

Uranium is a pollutant of concern to both human and ecosystem health. Uranium's redox state often dictates its partitioning between the aqueous- and solid-phases, and thus controls its dissolved concentration and, coupled with groundwater flow, its migration within the environment. In anaerobic environments, the more oxidized and mobile form of uranium (UO{sub 2}{sup 2+} and associated species) may be reduced, directly or indirectly, by microorganisms to U(IV) with subsequent precipitation of UO{sub 2}. However, various factors within soils and sediments may limit biological reduction of U(VI), inclusive of alterations in U(VI) speciation and competitive electron acceptors. Here we elucidate the impact of U(VI) speciation on the extent and rate of reduction with specific emphasis on speciation changes induced by dissolved Ca, and we examine the impact of Fe(III) (hydr)oxides (ferrihydrite, goethite and hematite) varying in free energies of formation on U reduction. The amount of uranium removed from solution during 100 h of incubation with S. putrefaciens was 77% with no Ca or ferrihydrite present but only 24% (with ferrihydrite) and 14% (no ferrihydrite) were removed for systems with 0.8 mM Ca. Imparting an important criterion on uranium reduction, goethite and hematite decrease the dissolved concentration of calcium through adsorption and thus tend to diminish the effect of calcium on uranium reduction. Dissimilatory reduction of Fe(III) and U(VI) can proceed through different enzyme pathways, even within a single organism, thus providing a potential second means by which Fe(III) bearing minerals may impact U(VI) reduction. We quantify rate coefficients for simultaneous dissimilatory reduction of Fe(III) and U(VI) in systems varying in Ca concentration (0 to 0.8 mM), and using a mathematical construct implemented with the reactive transport code MIN3P, we reveal the predominant influence of uranyl speciation, specifically the formation of uranyl-calcium-carbonato complexes, and ferrihydrite on the rate and extent of uranium reduction in complex geochemical systems.

Stewart, B.D.; Amos, R.T.; Nico, P.S.; Fendorf, S.

2010-03-15T23:59:59.000Z

325

Chemical Accelerators The phrase "chemical accelerators"  

E-Print Network (OSTI)

Meetings Chemical Accelerators The phrase "chemical accelerators" is scarcely older than for one or two dozen people grew to include nearly a hundred. Chemical accelerators is a name sug- gested-volt region. Thus chemical accelerators can provide the same type of information for elemen- tary chemical

Zare, Richard N.

326

Hyperspectral Aerosol Optical Depths from TCAP Flights  

SciTech Connect

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

327

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

328

Chemical Speciation of Sr, Am and Cm in high Level Waste: predictive modeling of phase partitioning during tank processing  

SciTech Connect

During this contract period, a number of papers were published. The papers prior to this report have been reported in earlier annual reports. This final report covers the 2005 & 2006 publications which have been published as well as the last few which have been submitted, but are still under review for acceptance for publication. The titles and abstracts of the papers are presented in section A, and the full published papers in Section B.

Choppin, Gregory R.

2006-12-20T23:59:59.000Z

329

The Two-Column Aerosol Project (TCAP) Science Plan  

SciTech Connect

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

330

Detection and speciation of transuranium elements in synthetic groundwater via pulsed-laser excitation  

SciTech Connect

High sensitivity methods for detection and speciation of complexed transuranium ions in synthetic basalt groundwater, and simplified analogs, are being developed which exploit advances in pulsed laser technology. The first demonstration of high sensitivity detection of a transuranium ion at temperatures significantly above ambient is reported using laser photoacoustic spectroscopy (LPAS). The existence of enhanced LPAS signal amplitudes with increasing temperature in aqueous solution is confirmed in LPAS spectra recorded at 30 C, 60 C and 90 C using micromolar concentrations of /sup 241/Am/sup 3+/. A detection sensitivity of 8.5 parts per trillion (weight basis) of /sup 244/Cm/sup 3+/ in a simplified basalt groundwater at 22 C has been achieved using laser-induced fluorescence spectroscopy (LIF). This corresponds to 1 x 10/sup 8/ Cm/sup 3+/ ions in the laser beam. The detailed spectroscopic information obtained by this method points to the existence of previously unobserved Cm/sup 3+/ species. A brief assessment of the applicability and sensitivity of LPAS and LIF methods for speciating transuranium ions in near-neutral pH aqueous solution, such as the groundwater expected in a basalt nuclear waste repository, is presented. 27 refs., 3 figs.

Beitz, J.V.; Bowers, D.L.; Doxtader, M.M.; Maroni, V.A.; Reed, D.T.

1987-01-01T23:59:59.000Z

331

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

SciTech Connect

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

332

Chemical Science  

NLE Websites -- All DOE Office Websites (Extended Search)

Chemical Science Chemical Science Compton double ionization of helium in the region of the cross-section maximum B. Krässig, R.W. Dunford, D.S. Gemmell, S. Hasegawa, E.P. Kanter, H. Schmidt-Böcking, W. Schmitt, S.H. Southworth, Th. Weber, and L. Young Crystal structure analysis of microporous Na16Nb12.8Ti3.2O44.8(OH)3.2l8H2O and Na/Nb/Zr/O/H2O phases A. Tripathi, J. Parise, M. Nyman, T.M. Nenoff, and W. Harrison Double K-photoionization of heavy atoms R.W. Dunford, D.S. Gemmell, E.P. Kanter, B. Krässig, and S.H. Southworth Forward-backward asymmetries of atomic photoelectrons S.H. Southworth, B. Krässig, E.P. Kanter, J.C. Bilheux, R.W. Dunford, D.S. Gemmell, S. Hasegawa, and L. Young In situreduction of various iron oxides to form high-surface-area Fe-metal catalysts as studied by high-resolution powder diffraction

333

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

SciTech Connect

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

334

PII S0016-7037(98)00209-9 Gold solubility and speciation in hydrothermal solutions: Experimental study of the  

E-Print Network (OSTI)

and deposition of gold in ore-forming processes. The most important ligands in hydrothermal gold-bearing soPII S0016-7037(98)00209-9 Gold solubility and speciation in hydrothermal solutions: Experimental Science Ltd 1. INTRODUCTION Field and mineralogical studies of hydrothermal gold deposits demonstrate

Paris-Sud XI, Université de

335

Evaluating the role of contracting and expanding rainforest in initiating cycles of speciation across the Isthmus of Panama  

Science Journals Connector (OSTI)

...cycles of speciation across the Isthmus of Panama Brian Tilston Smith 1 2 * Amei Amei 3...species diversity|neotropics|Isthmus of Panama|refuge model| 1. Introduction The...dispersal events across the Isthmus of Panama during alternating periods of suitable...

2012-01-01T23:59:59.000Z

336

Genomics of homoploid hybrid speciation: diversity and transcriptional activity of long terminal repeat retrotransposons in hybrid sunflowers  

Science Journals Connector (OSTI)

...Pamela S. Soltis and Jonathan F. Wendel Genomics of homoploid hybrid speciation: diversity...broad regulatory compatibility. BMC Genomics 14, 342. ( doi:10.1096/fj.10-170639...transposable elements in maize. BMC Genomics 11, 601. ( doi:10.1186/1471-2164-11-601...

2014-01-01T23:59:59.000Z

337

Lead Speciation in House Dust from Canadian Urban Homes Using EXAFS, Micro-XRF, and Micro-XRD  

Science Journals Connector (OSTI)

Lead Speciation in House Dust from Canadian Urban Homes Using EXAFS, Micro-XRF, and Micro-XRD ... As lead carbonate and basic lead carbonates were common ingredients in lead-based paints,(23) lead paint appears as the most probable source of the lead carbonates in the oldest home (CHDS-020). ...

Lachlan C. W. MacLean; Suzanne Beauchemin; Pat E. Rasmussen

2011-05-18T23:59:59.000Z

338

Aerosol-Based Duct Sealing Technology  

NLE Websites -- All DOE Office Websites (Extended Search)

8 8 Aerosol-Based Duct Sealing Technology During the past five years, research has quantified the impacts of residential duct system leakage on HVAC energy consumption and peak electricity demand. A typical house with ducts located in the attic or crawlspace wastes approximately 20% of heating and cooling energy through duct leaks and draws approximately 0.5 KW more electricity during peak cooling periods. A 1991 study indicated that sealing leaks could save close to one Quadrillion Btus per year. (see also Commercializing a New Technology) Because the major cost of sealing leaks in existing air distribution systems is the labor for the location and sealing process, reducing the labor could greatly improve the cost-effectiveness of such a retrofit. Field studies of duct sealing programs performed by HVAC contractors show

339

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

340

ARM - Datastreams - aosacsm  

NLE Websites -- All DOE Office Websites (Extended Search)

Datastreamsaosacsm Datastreamsaosacsm Documentation Data Quality Plots Citation DOI: 10.5439/1046180 [ What is this? ] Generate Citation Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Datastream : AOSACSM AOS: aerosol chemical speciation monitor Active Dates 2010.11.20 - 2014.01.02 Measurement Categories Aerosols Originating Instrument Aerosol Chemical Speciation Monitor (ACSM) Measurements Only measurements considered scientifically relevant are shown below by default. Show all measurements Measurement Units Variable Altitude above mean sea level m alt Inorganic chemical composition Mass concentration of ammonium, ambient aerosol in air. ug/m^3 ammonium ( time ) Mass to charge ratios of ion fragments m/z amus ( amus ) Base time in Epoch seconds since 1970-1-1 0:00:00 0:00 base_time

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

Discrimination between thin cirrus and and tropospheric aerosol using  

NLE Websites -- All DOE Office Websites (Extended Search)

Discrimination between thin cirrus and and tropospheric aerosol using Discrimination between thin cirrus and and tropospheric aerosol using multiple measurements from Darwin ARCS Mitchell, Ross CSIRO Category: Aerosols Thin cirrus cloud occurs frequently in the tropics, and is often difficult to distinguish from tropospheric aerosol on the basis of temporal variations in ground based measurements, since both can be rather spatially uniform. In this study we investigate their discrimination by combining data from three instruments at the Darwin Atmospheric Radiation and Cloud Station (ARCS): the Cimel sun photometer (CSP), the micropulse lidar (MPL), and the total sky imager (TSI). The study was carried out over the dry season of 2005, with the usual widespread burning of tropical savanna leading to extensive smoke plumes. It is shown that the locus of data in

342

Mobile Climate Observatory for Atmospheric Aerosols in India  

NLE Websites -- All DOE Office Websites (Extended Search)

Atmospheric Aerosols in India Atmospheric Aerosols in India Nainital, India, was the site chosen for deployment of a portable climate research laboratory to study how aerosols impact clouds and energy transfer in the atmosphere. The well-being of hundreds of millions of residents in northeastern India depends on the fertile land around the Ganges River, which is fed by monsoon rains and runoff from the nearby Himalayan Mountains. Any disturbance to the monsoon rains could threaten the population. In the same region, increased industrial activities due to economic growth are releasing small aerosol particles, such as soot and dust, that absorb and scatter sunlight and thus can change cloud formation processes and the heat distribution in the atmosphere. Such changes could greatly increase or

343

ARM - Field Campaign - Biogenic Aerosols - Effects on Clouds and Climate:  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsBiogenic Aerosols - Effects on Clouds and Climate: Snowfall govCampaignsBiogenic Aerosols - Effects on Clouds and Climate: Snowfall Experiment Related Campaigns Biogenic Aerosols- Effects on Clouds and Climate 2014.02.01, Petäjä, AMF Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Biogenic Aerosols - Effects on Clouds and Climate: Snowfall Experiment 2014.02.01 - 2014.04.30 Lead Scientist : Dmitri Moisseev Description The snowfall measurement campaign, which will take place during AMF2 deployment in Finland, will focus on understanding snowfall microphysics and characterizing performance of surface based snowfall measurement instruments. This will be achieved by combining triple frequency (X, Ka, W -band) radar observations of vertical structure of the precipitation,

344

PNNL-MILAGRO Aerosol Modeling in Mexico | Open Energy Information  

Open Energy Info (EERE)

PNNL-MILAGRO Aerosol Modeling in Mexico PNNL-MILAGRO Aerosol Modeling in Mexico Jump to: navigation, search Name PNNL-MILAGRO Aerosol Modeling in Mexico Agency/Company /Organization Pacific Northwest National Laboratory Topics Co-benefits assessment Resource Type Dataset, Maps Website http://www.pnl.gov/atmospheric Country Mexico UN Region Latin America and the Caribbean References PNNL-MILAGRO Aerosol Modeling in Mexico[1] "MILGARO surface data includes measurements from Supersites, RAMA (Red Automatica de Monitoreo Atmosferico), Mobile, and Other sites. A description of each site type follows along with a plot of the site locations. Supersites Supersites provide detailed atmospheric chemistry and meteorological measurements; these sites included: T0 (located at the Instituto Mexicano

345

A New Assessment of the Aerosol First Indirect Effect  

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New Assessment of the Aerosol First Indirect Effect New Assessment of the Aerosol First Indirect Effect Shao, Hongfei Florida State University Liu, Guosheng Florida State University Category: Aerosols The aerosol first indirect effect is known to cool the Earth radiatively. However, its magnitude is very uncertain; large discrepancies exist among the observed values published in the literature. In this study, we first survey the published values of those parameters used for describing the first indirect effect. By analyzing the discrepancies among these values, we show that the first indirect effect has been overestimated by many investigators due to an improper parameter being used. Therefore, we introduce a more meaningful parameter to measure this effect. We estimated the first indirect effect using the new parameter based on observational

346

Effects of operating conditions on a heat transfer fluid aerosol  

E-Print Network (OSTI)

are made over ranges of temperature, pressure and orifice diameters. Aerosol drop size distributions of a HTF are measured by a non-intrusive method of analysis using a Malvern Laser Diffraction Particle Analyzer (Malvern laser). The Malvern laser employs...

Sukmarg, Passaporn

2012-06-07T23:59:59.000Z

347

ARM - Field Campaign - Two-Column Aerosol Project (TCAP): Ground...  

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Discovery Browse Data Related Campaigns Two-Column Aerosol Project (TCAP) 2012.07.01, Berg, AMF Comments? We would love to hear from you Send us a note below or call us at...

348

ARM - Field Campaign - Two-Column Aerosol Project (TCAP): Winter...  

NLE Websites -- All DOE Office Websites (Extended Search)

Discovery Browse Data Related Campaigns Two-Column Aerosol Project (TCAP) 2012.07.01, Berg, AMF Comments? We would love to hear from you Send us a note below or call us at...

349

ARM - Field Campaign - Two-Column Aerosol Project (TCAP): Aerial...  

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Discovery Browse Data Related Campaigns Two-Column Aerosol Project (TCAP) 2012.07.01, Berg, AMF Comments? We would love to hear from you Send us a note below or call us at...

350

ARM - Field Campaign - Two-Column Aerosol Project (TCAP): Airborne...  

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Discovery Browse Data Related Campaigns Two-Column Aerosol Project (TCAP) 2012.07.01, Berg, AMF Comments? We would love to hear from you Send us a note below or call us at...

351

Application of computational fluid dynamics to aerosol sampling and concentration  

E-Print Network (OSTI)

, FLUENT 6 is used to analyze the performance of aerosol sampling and concentration devices including inlet components (impactors), cyclones, and virtual impactors. The ? ? k model was used to predict particle behavior in Inline Cone Impactor (ICI) and Jet...

Hu, Shishan

2009-05-15T23:59:59.000Z

352

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

353

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

SciTech Connect

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

354

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

355

Linearity of Climate Response to Increases in Black Carbon Aerosols  

Science Journals Connector (OSTI)

The impacts of absorbing aerosols on global climate are not completely understood. This paper presents the results of idealized experiments conducted with the Community Atmosphere Model, version 4 (CAM4), coupled to a slab ocean model (CAM4–SOM) ...

Salil Mahajan; Katherine J. Evans; James J. Hack; John E. Truesdale

2013-10-01T23:59:59.000Z

356

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

357

Impact of aerosols on convective clouds and precipitation  

E-Print Network (OSTI)

: Massachusetts Institute of Technology 77 Massachusetts Avenue, E19-411 Cambridge, MA 02139 (USA) Location to form and a significant attenuator of solar radiation, aerosols affect climate in several ways. Current

358

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

359

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

360

Atmospheric Aerosol Chemistry, Climate Change, and Air Quality  

NLE Websites -- All DOE Office Websites (Extended Search)

607 Atmospheric Aerosol Chemistry, Climate Change, and Air Quality An EMSL Science Theme Advisory Panel Workshop Workshop Date: January 30, 2013 Prepared for the U.S. Department of...

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

ARM - Field Campaign - Shortwave Radiation and Aerosol Intensive  

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govCampaignsShortwave Radiation and Aerosol Intensive Observation govCampaignsShortwave Radiation and Aerosol Intensive Observation Periods Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Shortwave Radiation and Aerosol Intensive Observation Periods 1998.08.03 - 1998.08.28 Lead Scientist : Warren Wiscombe For data sets, see below. Summary Wednesday, August 5, 1998: IOP Opening Activities: The IOP updates for the Shortwave/Aerosol/BDRF will be composed from notes taken during briefing sessions lead by Don Cahoon and company each night at the Marland Mansion in Ponca City. IOP Status as of 8/4/98 Weather forecasts indicate that cloudy conditions will prevail for the next few days. The Helicopter is on standby for clear sky conditions. Model output indicates clear sky's may move in later this week.

362

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

SciTech Connect

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

363

A Numerical Sensitivity Study of Aerosol Influence on Immersion Freezing  

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Numerical Sensitivity Study of Aerosol Influence on Immersion Freezing Numerical Sensitivity Study of Aerosol Influence on Immersion Freezing in Mixed-Phase Stratiform Clouds Gijs de Boer, Tempei Hashino, Edwin W. Eloranta and Gregory J. Tripoli The University of Wisconsin - Madison (1) Introduction (1) Introduction Mixed-phase stratiform clouds are commonly observed at high latitudes (Shupe et al., 2006; de Boer et al., 2009a). These clouds significaly impact the atmospheric radiative

364

Representing Cloud Processing of Aerosol in Numerical Models  

SciTech Connect

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

365

Non-intrusive characterization of heat transfer fluid aerosol formation  

E-Print Network (OSTI)

providing an ignition source for the fine aerosol droplets. TI&e Malvern Laser Diffraction Particle Analyzer RING DIODE ARRAY DETECTOR BEAM EXPANDER/ SPATIAL FILTER HE- NE LASER FOURIER TRANSFORM LENS Figure II-Z. Diffraction particle analyzer... providing an ignition source for the fine aerosol droplets. TI&e Malvern Laser Diffraction Particle Analyzer RING DIODE ARRAY DETECTOR BEAM EXPANDER/ SPATIAL FILTER HE- NE LASER FOURIER TRANSFORM LENS Figure II-Z. Diffraction particle analyzer...

Krishna, Kiran

2012-06-07T23:59:59.000Z

366

On modification of global warming by sulfate aerosols  

SciTech Connect

There is increasing evidence that the response of climate to increasing greenhouse gases may be modified by accompanying increases in sulfate aerosols. In this study, the patterns of response in the surface climatology of a coupled ocean-atmosphere general circulation model forced by increases in carbon dioxide alone is compared with those obtained by increasing carbon dioxide and aerosol forcing. The simulations are run from early industrial times using the estimated historical forcing and continued to the end of the twenty-first century assuming a nonintervention emissions scenario for greenhouse gases and aerosols. The comparison is made for the period 2030-2050 when the aerosol forcing is a maximum. In winter, the cooling due to aerosols merely tends to reduce the response to carbon dioxide, whereas in summer, it weakens the monsoon circulations and reverses some of the changes in the hydrological cycle on increasing carbon dioxide. This response is in some respects similar to that found in simulations with changed orbital parameters, as between today and the middle Holocene. The hydrological response in the palaeosimulations is supported by palaeoclimatic reconstructions. The results of changes in aerosol concentrations of the magnetic projected in the scenarios would have a major effect on regional climate, especially over Europe and Southeast Asia. 74 refs., 12 figs., 6 tabs.

Mitchell, J.F.B.; Johns, T.C. [Hadley Centre for Climate Prediction and Research, Berkshire (United Kingdom)] [Hadley Centre for Climate Prediction and Research, Berkshire (United Kingdom)

1997-02-01T23:59:59.000Z

367

Characterisation and dissolution of depleted uranium aerosols produced during impacts of kinetic energy penetrators against a tank  

Science Journals Connector (OSTI)

......Characterisation and dissolution of depleted uranium aerosols produced during impacts...Aerosols produced during impacts of depleted uranium (DU) penetrators against the...Characterisation and dissolution of depleted uranium aerosols produced during impacts......

V. Chazel; P. Gerasimo; V. Debouis; P. Laroche; F. Paquet

2003-07-01T23:59:59.000Z

368

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

SciTech Connect

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

369

Importance of Speciation in Understanding Mercury Bioaccumulation in Tilapia Controlled by Salinity and Dissolved Organic Matter  

Science Journals Connector (OSTI)

As we expected, the changes in Hg(II) uptake rates were consistent with the HgCl2 speciation (Figure 2), i.e., initially increased and then decreased with the salinity gradient (0, 2, and 6 psu) and topped out at 2 psu, again indicating the important role of the neutral species. ... MeHgCl and MeHgOH are the most important MeHg species, with MeHgCl dominating in all saline waters (pCl salinity higher than 0.06 psu; (13)). ... The water uptake of gills after 2-h exposure was significantly higher at lower salinities, and exhibited a good negative correlation with salinity (r2 = 92%). ...

Rui Wang; Wen-Xiong Wang

2010-09-17T23:59:59.000Z

370

Lead exposures and biological responses in military weapons systems: Aerosol characteristics and acute lead effects among US Army artillerymen: Final report  

SciTech Connect

This study was to determine the concentration and chemical nature of lead (Pb) aerosols produced during the firing of artillery and to determine the exposures and biological responses of crew members exposed to lead aerosols during such firing. The concentrations of lead-containing aerosols at crew positions depended on wind conditions, with higher concentrations when firing into a head wind. Aerosol concentrations were highest in the muzzle blast zone. Concentrations of lead in the blood of crew members rose during the first 12 days of exposure to elevated airborne lead concentrations and then leveled off. There was no rapid decrease in blood lead concentrations after completion of firing. Small decreases in hematocrit and small increases in free erythrocyte porphyrin were correlated with increasing exposure to airborne lead. These changes were reversed by seven weeks after firing. Changes in nerve conduction velocity had borderline statistical significance to airborne lead exposure. In measuring nerve conduction velocity, differences in skin temperature must be taken into account.

Bhattacharyya, M.H.; Stebbings, J.H.; Peterson, D.P.; Johnson, S.A.; Kumar, R.; Goun, B.D.; Janssen, I.; Trier, J.E.

1993-03-01T23:59:59.000Z

371

Speciation of Selenium, Arsenic, and Zinc in Class C Fly Ash  

SciTech Connect

A major environmental concern associated with coal fly ash is the mobilization of trace elements that may contaminate water. To better evaluate proper use of fly ash, determine appropriate disposal methods, and monitor postdisposal conditions, it is important to understand the speciation of trace elements in fly ash and their possible environmental impact. The speciation of selenium, arsenic, and zinc was determined in five representative Class C fly ash samples from combustion of sub-bituminous Powder River Basin coal using synchrotron-based X-ray absorption spectroscopy to provide an improved understanding of the mechanisms of trace element association with the fly ash. Selenium in all fly ash samples occurs predominantly as Se(IV), with the exception of one sample, in which there was a minor amount of Se(0). Se(0) is likely associated with the high content of unburned coal in the sample. Arsenic exists in the fly ash as a single phase most consistent with calcium pyroarsenate. In contrast, zinc occurs as two distinct species in the silicate glass matrix of the fly ash. This work demonstrates that residual carbon in fly ash may reduce potential Se mobility in the environment by retaining it as less soluble elemental Se instead of Se(IV). Further, this work suggests that As and Zn in Class C fly ash will display substantially different release and mobilization behaviors in aquatic environments. While As release will primarily depend upon the dissolution and hydrolysis of calcium pyroarsenate, Zn release will be controlled by the dissolution of alkaline aluminosilicate glass in the ash.

Luo, Yun; Giammar, Daniel E.; Huhmann, Brittany L.; Catalano, Jeffrey G. (WU)

2011-11-17T23:59:59.000Z

372

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

E-Print Network (OSTI)

from a low-speed marine diesel engine, Aerosol Sci. Tech. ,from a low-speed marine diesel engine, Aerosol Sci. Tech. ,

Gaston, Cassandra Jayne

2012-01-01T23:59:59.000Z

373

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

SciTech Connect

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

374

Organic Particles Kevin Wilson Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA  

NLE Websites -- All DOE Office Websites (Extended Search)

for Studying the Chemical Transformations of for Studying the Chemical Transformations of Organic Particles Kevin Wilson Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA Molecular weight growth and decomposition chemistries play important roles in the transformation of particles from soot formation to atmospheric aerosol oxidation. Understanding these complex reaction pathways requires novel methods of analyzing particle phase hydrocarbons. We are developing a suite of synchrotron-based tools to provide better insights into the molecular composition, isomer distribution, and elemental composition of complex hydrocarbon mixtures, aimed at developing simple yet realistic descriptions of molecular weight growth and decomposition that occur during a heterogeneous reaction.

375

Chemical structure and dynamics. Annual report 1994  

SciTech Connect

The Chemical Structure and Dynamics program was organized as a major component of Pacific Northwest Laboratory`s Environmental and Molecular Sciences Laboratory (EMSL), a state-of-the-art collaborative facility for studies of chemical structure and dynamics. Our program responds to the need for a fundamental, molecular-level understanding of chemistry at the wide variety of environmentally important interfaces by (1) extending the experimental characterization and theoretical description of chemical reactions to encompass the effects of condensed media and interfaces, and (2) developing a multidisciplinary capability for describing interfacial chemical processes within which the new knowledge generated can be brought to bear on complex phenomena in environmental chemistry and in nuclear waste processing and storage. This research effort was initiated in 1989 and will continue to evolve over the next few years into a program of rigorous studies of fundamental molecular processes in model systems, such as well-characterized surfaces, single-component solutions, clusters, and biological molecules; and studies of complex systems found in the environment (multispecies, multiphase solutions; solid/liquid, liquid/liquid, and gas/surface interfaces; colloidal dispersions; ultrafine aerosols; and functioning biological systems). The success of this program will result in the achievement of a quantitative understanding of chemical reactions at interfaces, and more generally in condensed media, that is comparable to that currently available for gas-phase reactions. This understanding will form the basis for the development of a priori theories for predictions of macroscopic chemical behavior in condensed and heterogeneous media, adding significantly to the value of field-scale environmental models, the prediction of short- and long-term nuclear waste storage stabilities, and other problems related to the primary missions of the DOE.

Colson, S.D.

1995-07-01T23:59:59.000Z

376

High-Resolution Mass Spectroscopic Analysis of Secondary Organic Aerosol Generated by Ozonolysis of Isoprene  

SciTech Connect

The chemical composition of secondary organic aerosol (SOA) generated from the ozonolysis of isoprene (C5H8) in the presence of an OH scavenger was examined using high-resolution electrospray ionization mass spectrometry (ESI-MS). The chemical composition of SOA is complex, with more than 1000 assigned peaks observed in the positive and negative ion mode spectra. Only a small fraction of peaks corresponds to known products of isoprene oxidation, such as pyruvic acid, glycolic acid, methylglyoxal, etc. The absolute majority of the detected peaks correspond to highly oxidized oligomeric constituents of SOA, with an average O:C molar ratio of ~0.6. The corresponding organic mass (OM) to organic oxygen (OO) ratio is OM/OO?2.4. Approximately 8% of oxygen atoms in SOA are in the form of peroxides as quantified with an iodide test. Double bond equivalency (DBE) factors, representing the sum of all double bonds and rings, increase by 1 for every 2-3 additional carbon atoms in the molecule. The prevalent oligomer building blocks are therefore carbonyls or carboxylic acids with a C2-C3 skeleton. Kendrick analysis suggests that simple aldehydes, specifically formaldehyde, acetaldehyde, and methylglyoxal can serve as monomeric building blocks in the observed oligomers. The large number of reactive functional groups, especially organic peroxides and carbonyls, suggests that isoprene/O3 SOA should be prone to chemical and photochemical aging.

Nguyen, Tran B.; Bateman, Adam P.; Bones, David L.; Nizkorodov, Serguei; Laskin, Julia; Laskin, Alexander

2010-02-01T23:59:59.000Z

377

Measurements of NO2 and Analysis of Submicron Aerosol Composition in the ARM-Related Experiment at Zvenigorod in March-April 2002 and During Forest and Peatbog Fires in July-September 2002  

NLE Websites -- All DOE Office Websites (Extended Search)

Measurements of NO Measurements of NO 2 and Analysis of Submicron Aerosol Composition in the ARM-Related Experiment at Zvenigorod in March-April 2002 and During Forest and Peatbog Fires in July-September 2002 L. M. Shukurova, A. S. Elokhov, K. A. Shukurov, A. N. Gruzdev, and G. S. Golitsyn A.M. Obukhov Institute of Atmospheric Physics Russian Academy of Sciences Moscow, Russia Introduction One insufficiently explored problem is the effect of pollution of the lower troposphere by nitrogen oxides on the chemical composition and microphysical properties of atmospheric aerosol. Earlier experimental studies showed that submicron aerosol collected during anthropogenic pollution episodes in winter could contain the nitric acid component (Shukurova et al. 2001). In this study, we present

378

E-Print Network 3.0 - aerosols apports du Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

Summary: Regional Impact of Inter-Continental Aerosol Transport Leona Charles*a,b , Barry Grossa, Fred... to study the interaction of aerosols in the PBL with long range...

379

Organic Aerosol Formation from Photochemical Oxidation of Diesel Exhaust in a Smog Chamber  

Science Journals Connector (OSTI)

Diluted exhaust from a diesel engine was photo-oxidized in a smog chamber to investigate secondary organic aerosol (SOA) production. Photochemical aging rapidly produces significant SOA, almost doubling the organic aerosol contribution of primary ...

Emily A. Weitkamp; Amy M. Sage; Jeffrey R. Pierce; Neil M. Donahue; Allen L. Robinson

2007-09-11T23:59:59.000Z

380

Comparison of Carbonaceous Aerosols in Tokyo before and after Implementation of Diesel Exhaust Restrictions  

Science Journals Connector (OSTI)

Comparison of Carbonaceous Aerosols in Tokyo before and after Implementation of Diesel Exhaust Restrictions ... (5)?Albert, R. E. Comparative carcinogenic potencies of particulates from diesel engine exhausts, coke oven emissions, roofing tar aerosols and cigarette smoke. ...

Naomichi Yamamoto; Atsushi Muramoto; Jun Yoshinaga; Ken Shibata; Michio Endo; Osamu Endo; Motohiro Hirabayashi; Kiyoshi Tanabe; Sumio Goto; Minoru Yoneda; Yasuyuki Shibata

2007-08-15T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

E-Print Network 3.0 - aerosol lidar profilometer Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

CLASIC Summary: Lidar RH Changes in aerosol properties and RH near clouds Airborne NASA LaRC HSRL, ARM SGP ground... ) RamanLidar RelativeHumidityRamanLidar Aerosol Extensive...

382

The Evolution of the Physicochemical Properties of Aerosols in the Atmosphere  

E-Print Network (OSTI)

campaign investigated the evolution of the physicochemical properties of the Asian aerosol plume after 3 to 7 days of transport. The Asian aerosol within the free troposphere exhibited a bimodal growth distribution roughly 50 percent of the time. The more...

Tomlinson, Jason

2011-02-22T23:59:59.000Z

383

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

384

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

385

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

386

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

NLE Websites -- All DOE Office Websites (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...

387

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

388

Estimating the lung burden from exposure to aerosols of depleted uranium  

Science Journals Connector (OSTI)

......from exposure to aerosols of depleted uranium Marcelo Valdes * * Corresponding...Following exposure to aerosols of depleted uranium (DU), biological samples...uranyl phosphates. INTRODUCTION Depleted uranium (DU) is a waste product of......

Marcelo Valdés

2009-02-01T23:59:59.000Z

389

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

390

Investigation of the aerosol-cloud interaction using the WRF framework  

E-Print Network (OSTI)

In this dissertation, a two-moment bulk microphysical scheme with aerosol effects is developed and implemented into the Weather Research and Forecasting (WRF) model to investigate the aerosol-cloud interaction. Sensitivities of cloud properties...

Li, Guohui

2009-05-15T23:59:59.000Z

391

E-Print Network 3.0 - aerosol flame deposition Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

search results for: aerosol flame deposition Page: << < 1 2 3 4 5 > >> 1 Flame aerosol nano-technology has been developed to preparation of thin and defect-free porous membrane...

392

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

393

The Sensitivity of a Numerically Simulated Idealized Squall Line to the Vertical Distribution of Aerosols  

Science Journals Connector (OSTI)

Changes in the aerosol number concentration are reflected by changes in raindrop size and number concentration that ultimately affect the strength of cold pools via evaporation. Therefore, aerosol perturbations can potentially alter the balance ...

Zachary J. Lebo

2014-12-01T23:59:59.000Z

394

ARM - Site Instruments  

NLE Websites -- All DOE Office Websites (Extended Search)

Central FacilityInstruments Central FacilityInstruments SGP Related Links Facilities and Instruments Central Facility Boundary Facility Extended Facility Intermediate Facility Radiometric Calibration Facility Geographic Information ES&H Guidance Statement Operations Science Field Campaigns Visiting the Site Fact Sheet Images Information for Guest Scientists Contacts Instruments : Central Facility [ Single installation ] ACSM Aerosol Chemical Speciation Monitor Aerosols Browse Data [ Single installation ] AERI Atmospheric Emitted Radiance Interferometer Radiometric Browse Plots Browse Data [ Single installation ] AOS Aerosol Observing System Aerosols Browse Plots Browse Data [ Single installation ] BRS Broadband Radiometer Station Radiometric Browse Plots Browse Data [ Single installation ] BSRN Baseline Solar Radiation Network

395

ARM - Site Instruments  

NLE Websites -- All DOE Office Websites (Extended Search)

PlainsInstruments PlainsInstruments SGP Related Links Facilities and Instruments Central Facility Boundary Facility Extended Facility Intermediate Facility Radiometric Calibration Facility Geographic Information ES&H Guidance Statement Operations Science Field Campaigns Visiting the Site Fact Sheet Images Information for Guest Scientists Contacts Instruments : Southern Great Plains [ Single installation ] ACSM Aerosol Chemical Speciation Monitor Aerosols Browse Data [ Installed at 5 facilities ] AERI Atmospheric Emitted Radiance Interferometer Radiometric Browse Plots Browse Data [ Single installation ] AOS Aerosol Observing System Aerosols Browse Plots Browse Data [ Single installation ] BRS Broadband Radiometer Station Radiometric Browse Plots Browse Data [ Single installation ] BSRN Baseline Solar Radiation Network

396

Parameterizations of Cloud Microphysics and Indirect Aerosol Effects  

SciTech Connect

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

397

CARES: Carbonaceous Aerosol and Radiative Effects Study Operations Plan  

SciTech Connect

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

398

Calculating Capstone Depleted Uranium Aerosol Concentrations from Beta Activity Measurements  

SciTech Connect

Beta activity measurements were used as surrogate measurements of uranium mass in aerosol samples collected during the field testing phase of the Capstone Depleted Uranium (DU) Aerosol Study. These aerosol samples generated by the perforation of armored combat vehicles were used to characterize the depleted uranium (DU) source term for the subsequent human health risk assessment (HHRA) of Capstone aerosols. Establishing a calibration curve between beta activity measurements and uranium mass measurements is straightforward if the uranium isotopes are in equilibrium with their immediate short-lived, beta-emitting progeny. For DU samples collected during the Capstone study, it was determined that the equilibrium between the uranium isotopes and their immediate short lived, beta-emitting progeny had been disrupted when penetrators had perforated target vehicles. Adjustments were made to account for the disrupted equilibrium and for wall losses in the aerosol samplers. Correction factors for the disrupted equilibrium ranged from 0.16 to 1, and the wall loss correction factors ranged from 1 to 1.92.

Szrom, Fran; Falo, Gerald A.; Parkhurst, MaryAnn; Whicker, Jeffrey J.; Alberth, David P.

2009-03-01T23:59:59.000Z

399

Electrohydrodynamic atomization (EHDA) assisted wet chemical synthesis of nickel nanoparticles  

SciTech Connect

Highlights: ? Electrohydrodynamic atomization (EHDA) assisted chemical synthesis of nickel nanoparticles is reported. ? Substituting water with non-aqueous media prevents the formation of nickel hydroxide. ? Size of particles decreased from 10 to 20 nm down to 2–4 nm by using multi-jet mode. ? Synthesized nanoparticles have diffraction patterns similar to amorphous materials. -- Abstract: In this study nickel nanoparticles were prepared via chemical reduction of nickel acetate using sodium borohydride using electrohydrodynamic atomization (EHDA) technique. This technique was used to spray a finely dispersed aerosol of nickel precursor solution into the reductive bath. Obtained particles were characterized by means of X-ray diffraction (XRD), UV–Visible spectroscopy, and transmission electron microscopy (TEM). Results confirmed the formation of nickel nanoparticles and showed that applying EHDA technique to chemical reduction method results in producing smaller particles with narrower size distribution in comparison with conventional reductive precipitation method.

Barzegar Vishlaghi, M. [Department of Mechanical Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of)] [Department of Mechanical Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of); Farzalipour Tabriz, M., E-mail: meisam.fa@gmail.com [Department of Mechanical Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of); Mohammad Moradi, O. [Department of Mechanical Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of)] [Department of Mechanical Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of)

2012-07-15T23:59:59.000Z

400

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

NLE Websites -- All DOE Office Websites (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 chemical speciation" 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

E-Print Network 3.0 - aerosol generation characterization Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

Summary: , Brookhaven National Laboratory: "Characterization of Aerosol Organic Matter: Detection, Formation and Optical... : "Atmospheric Formation, Transformation, and...

402

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

NLE Websites -- All DOE Office Websites (Extended Search)

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

403

Characterization of Pre-Commercial Gasoline Engine Particulates Through Advanced Aerosol Methods  

Energy.gov (U.S. Department of Energy (DOE))

Advanced aerosol analysis methods were used to examine particulates from single cylinder test engines running on gasoline and ethanol blends.

404

CAMD Cleanroom Chemical List  

NLE Websites -- All DOE Office Websites (Extended Search)

CAMD Cleanroom Chemical List Chemicals on this list are routine use chemicals in the CAMD Cleanroom and are available to users for general use. All others (*) are approved for use...

405

Coordination chemistry of two heavy metals: I, Ligand preferences in lead(II) complexation, toward the development of therapeutic agents for lead poisoning: II, Plutonium solubility and speciation relevant to the environment  

SciTech Connect

The coordination chemistry and solution behavior of the toxic ions lead(II) and plutonium(IV, V, VI) have been investigated. The ligand pK{sub a}s and ligand-lead(II) stability constants of one hydroxamic acid and four thiohydroaxamic acids were determined. Solution thermodynamic results indicate that thiohydroxamic acids are more acidic and slightly better lead chelators than hydroxamates, e.g., N-methylthioaceto-hydroxamic acid, pK{sub a} = 5.94, log{beta}{sub 120} = 10.92; acetohydroxamic acid, pK{sub a} = 9.34, log{beta}{sub l20} = 9.52. The syntheses of lead complexes of two bulky hydroxamate ligands are presented. The X-ray crystal structures show the lead hydroxamates are di-bridged dimers with irregular five-coordinate geometry about the metal atom and a stereochemically active lone pair of electrons. Molecular orbital calculations of a lead hydroxamate and a highly symmetric pseudo octahedral lead complex were performed. The thermodynamic stability of plutonium(IV) complexes of the siderophore, desferrioxamine B (DFO), and two octadentate derivatives of DFO were investigated using competition spectrophotometric titrations. The stability constant measured for the plutonium(IV) complex of DFO-methylterephthalamide is log{beta}{sub 110} = 41.7. The solubility limited speciation of {sup 242}Pu as a function of time in near neutral carbonate solution was measured. Individual solutions of plutonium in a single oxidation state were added to individual solutions at pH = 6.0, T = 30.0, 1.93 mM dissolved carbonate, and sampled over intervals up to 150 days. Plutonium solubility was measured, and speciation was investigated using laser photoacoustic spectroscopy and chemical methods.

Neu, M.P. [Lawrence Berkeley Lab., CA (United States)

1993-11-01T23:59:59.000Z

406

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

407

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

408

chemical analysis | EMSL  

NLE Websites -- All DOE Office Websites (Extended Search)

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

409

TRENDS in Chemical Marketing  

Science Journals Connector (OSTI)

TRENDS in Chemical Marketing ... BEFORE any chemical sales organization, can meet or establish new trends in marketing, it must be completely aware of the problem it faces. ...

W. M. RUSSELL

1955-08-29T23:59:59.000Z

410

Genetic evaluation of the role of cryptic structural differences as a mechanism of speciation in Gossypium hirsutum and Gossypium barbadense  

E-Print Network (OSTI)

GENETIC EVALUATION OF THE ROLE OF CRYPTIC STRUCTURAL DIFFERENCES AS A MECHANISM OF SFECIATION IN GOSSYPIUM HIRSUTUM AND GOSSYPIUM BARBADENSE A Dissertation By Harold Dickson Loden Major Subject: Genetics Approved as to style and content... by Chairman of Committee June, 1951 GENETIC EVALUATION OF THE ROLE OF CRYPTIC STRUCTURAL DIFFERENCES AS A MECHANISM OF SPECIATION IN GOSSYPIUM HIRSUTUM AND GOSSYPIUM BARBADENSE By Harold Dickson Loden A Dissertation Submitted to the Graduate School...

Loden, Harold Dickson

1951-01-01T23:59:59.000Z

411

Surface based remote sensing of aerosol-cloud interactions  

NLE Websites -- All DOE Office Websites (Extended Search)

Surface based remote sensing of aerosol-cloud interactions Surface based remote sensing of aerosol-cloud interactions Feingold, Graham NOAA/Environmental Technology Laboratory Frisch, Shelby NOAA/Environmental Technology Laboratory Min, Qilong State University of New York at Albany Category: Cloud Properties We will present an analysis of the effect of aerosol on clouds at the Southern Great Plains ARM site. New methods for retrieving cloud droplet effective radius with radar (MMCR), multifilter rotating shadowband radiometer (MFRSR), and microwave radiometer (MWR) will be discussed. Relationships based on adiabatic clouds will be used to constrain retrievals. We will investigate the use of a range of proxies for cloud condensation nuclei, ranging from surface measurements of light scattering and accumulation mode number concentration, to lidar-measured extinction or

412

ARM - Publications: Science Team Meeting Documents: Effects of Aerosol Size  

NLE Websites -- All DOE Office Websites (Extended Search)

Effects of Aerosol Size Distribution and Vertical Profile on the Effects of Aerosol Size Distribution and Vertical Profile on the Polarization in the Oxygen A-Band Duan, Minzheng State University of New York at Albany Min, Qilong State University of New York at Albany A vector radiative transfer code with successive order of scattering method was used to simulate the high-resolution polarization spectra in the oxygen A-band. The effects of aerosol size distribution and vertical profile on the radiance and polarization at the top and bottom of the atmosphere were analyzed. The impacts of instrument specification on information content are also analyzed. Polarized radiances were dominated (>95%) by the first and second orders of scattering. The contributions of scattering from different levels to the TOA and surface observation are analyzed. The

413

ARM - Evaluation Product - Aerosol Optical Depths from SASHE  

NLE Websites -- All DOE Office Websites (Extended Search)

ProductsAerosol Optical Depths from SASHE ProductsAerosol Optical Depths from SASHE Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : Aerosol Optical Depths from SASHE Site(s) PVC SGP General Description The Shortwave Array Spectroradiometer Hemispheric (SASHE) is a ground-based instrument that measures both direct and diffuse shortwave irradiance. In this regard, the instrument is similar to the multifilter rotating shadowband radiometer (MFRSR)-an instrument that has been in the ARM Facility stable for more than 15 years. However, the two instruments differ significantly in wavelength resolution and range. In particular, the SASHE provides hyperspectral measurements from about 350 nm to 1700 nm at a wavelength resolution from 1 to several nanometers, while the MFRSR only

414

Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant Particles  

NLE Websites -- All DOE Office Websites (Extended Search)

2414 2414 1 Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant Particles M. P. Modera, O. Brzozowski ** , F. R. Carrié * , D. J. Dickerhoff, W. W. Delp, W. J. Fisk, R. Levinson, D. Wang Abstract Electricity energy savings potential by eliminating air leakage from ducts in large commercial buildings is on the order of 10 kWh/m 2 per year (1 kWh/ft 2 ). We have tested, in two large commercial buildings, a new technology that simultaneously seals duct leaks and measures effective leakage area of ducts. The technology is based upon injecting a fog of aerosolized sealant particles into a pressurized duct system. In brief, this process involves blocking all of the intentional openings in a duct system (e.g., diffusers). Therefore, when the system is pressurized, the only place for the air carrying the aerosol

415

ARM - Field Campaign - Ganges Valley Aerosol Experiment (GVAX)  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsGanges Valley Aerosol Experiment (GVAX) govCampaignsGanges Valley Aerosol Experiment (GVAX) Campaign Links Science Plan AMF India Deployment Website Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Ganges Valley Aerosol Experiment (GVAX) 2011.06.13 - 2012.03.31 Website : http://www.arm.gov/sites/amf/pgh/ Lead Scientist : V. Rao Kotamarthi Description 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 monsoon. Impacts of changes in precipitation patterns, temperature, and the flow of the snow-fed rivers could be immense. Recent satellite-based measurements have indicated that

416

Lognormal Size Distribution Theory for Deposition of Polydisperse Aerosol Particles  

SciTech Connect

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

417

ARM - PI Product - Aerosol Retrievals from ARM SGP MFRSR Data  

NLE Websites -- All DOE Office Websites (Extended Search)

ProductsAerosol Retrievals from ARM SGP MFRSR Data ProductsAerosol Retrievals from ARM SGP MFRSR Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Aerosol Retrievals from ARM SGP MFRSR Data 2000.01.01 - 2000.12.31 Site(s) SGP General Description 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

418

Speciation study of the heavy metals in commercially available recharge cards coatings in Nigeria and the health implication  

Science Journals Connector (OSTI)

Abstract This work assessed levels of heavy metals exposure from silver coatings of mobile phones recharge cards of three major companies (designated as A, B and C) with price denominations 100, 200 and 400 from companies A, B and C respectively, which were carefully scratched using a plastic scraper into a glass tube. The coatings were acid digested for total metal concentration, while speciation experiment for Mn, Cu, Cd and Pb was carried out. Total metals and speciation analysis were done using AAS and XRF techniques. The total metal concentration from XRF analysis was in the range: Ca (70–2140 ?g/g), K (20–4930 ?g/g), Sc (80–270 ?g/g), Ti (1530–12,580 ?g/g), Fe (50–6660 ?g/g), Ni (20–2040 ?g/g), Cu (20–850 ?g/g) and Zn (40–460 ?g/g). Cr had the lowest concentration (10 ?g/g) in A ( 400) while Ti had the highest concentration (12,580 ?g/g) in C ( 500) for all the coatings analyzed. AAS and XRF results agreed closely except for Fe with higher concentration. A ( 100) contained high concentration of the metals compared with others. Speciation study identified Mn as the most mobile element when present in the environment.

Abolanle S. Adekunle; John A.O. Oyekunle; Suliat O. Baruwa; Aderemi O. Ogunfowokan; Eno E. Ebenso

2014-01-01T23:59:59.000Z

419

Lead Speciation in House Dust from Canadian Urban Homes Using EXAFS Micro-XRF and Micro-XRD  

SciTech Connect

X-ray absorption fine-structure (XAFS) spectroscopy, micro-X-ray fluorescence ({mu}XRF), and micro-X-ray diffraction ({mu}XRD) were used to determine the speciation of Pb in house dust samples from four Canadian urban homes having elevated Pb concentrations (>1000 mg Pb kg{sup -1}). Linear combination fitting of the XAFS data, supported by {mu}XRF and {mu}XRD, shows that Pb is complexed in a variety of molecular environments, associated with both the inorganic and organic fractions of the dust samples. The inorganic species of lead identified were as follows: Pb metal, Pb carbonate, Pb hydroxyl carbonate, Pb oxide, and Pb adsorbed to iron oxyhydroxides. Pb carbonate and/or Pb hydroxyl carbonate occurred in all four dust samples and accounted for 28 to 75% of total Pb. Pb citrate and Pb bound to humate were the organic species identified. The results of this study demonstrate the ability of XAFS to identify Pb speciation in house dust and show the potential to identify Pb sources from new homes versus older homes. Understanding Pb speciation and how it influences bioaccessibility is important for human health risk assessment and risk management decisions which aim to improve indoor environmental health.

L MacLean; S Beauchemin; P Rasmussen

2011-12-31T23:59:59.000Z

420

Airborne measurements of carbonaceous aerosols in southern Africa during  

NLE Websites -- All DOE Office Websites (Extended Search)

Airborne measurements of carbonaceous aerosols in southern Africa during Airborne measurements of carbonaceous aerosols in southern Africa during the dry, biomass burning season Title Airborne measurements of carbonaceous aerosols in southern Africa during the dry, biomass burning season Publication Type Journal Article LBNL Report Number LBNL-50880 Year of Publication 2003 Authors Kirchstetter, Thomas W., Tihomir Novakov, and Peter V. Hobbs Journal Journal of Geophysical Research - Atmospheres Keywords black carbon, evolved gas analysis, light absorption, organic carbon, positive sampling artifact, SAFARI Abstract Particulate matter collected aboard the University of Washington's Convair-580 research aircraft over southern Africa during the dry, biomass burning season was analyzed for total carbon, organic carbon, and black carbon contents using thermal and optical methods. Samples were collected in smoke plumes of burning savanna and in regional haze. A known artifact, produced by the adsorption of organic gases on the quartz filter substrates used to collect the particulate matter samples, comprised a significant portion of the total carbon collected. Consequently, conclusions derived from the data are greatly dependent on whether or not organic carbon concentrations are corrected for this artifact. For example, the estimated aerosol co-albedo (1 - single scattering albedo), which is a measure of aerosol absorption, of the biomass smoke samples is 60% larger using corrected organic carbon concentrations. Thus, the corrected data imply that the biomass smoke is 60% more absorbing than do the uncorrected data. The black carbon to (corrected) organic carbon mass ratio (BC/OC) of smoke plume samples (0.18±0.06) is lower than that of samples collected in the regional haze (0.25±0.08). The difference may be due to mixing of biomass smoke with background air characterized by a higher BC/OC ratio. A simple source apportionment indicates that biomass smoke contributes about three-quarters of the aerosol burden in the regional haze, while other sources (e.g., fossil fuel burning) contribute the remainder.

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

Distinguishing Aerosol Impacts on Climate Over the Past Century  

SciTech Connect

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

422

On surface temperature, greenhouse gases, and aerosols: models and observations  

SciTech Connect

The effect of changes in atmospheric carbon dioxide concentrations and sulphate aerosols on near-surface temperature is investigated using a version of the Hadley Centre atmospheric model coupled to a mixed layer ocean. The scattering of sunlight by sulphate aerosols is represented by appropriately enhancing the surface albedo. On doubling atmospheric carbon dioxide concentrations, the global mean temperature increases by 5.2 K. An integration with a 39% increase in CO{sub 2}, giving the estimated change in radiative heating due to increases in greenhouse gases since 1900, produced an equilibrium warming of 2.3 K, which, even allowing for oceanic inertia, is significantly higher than the observed warming over the same period. Furthermore, the simulation suggests a substantial warming everywhere, whereas the observations indicate isolated regions of cooling, including parts of the northern midlatitude continents. The addition of an estimate of the effect of scattering by current industrial aerosols (uncertain by a factor of at least 3) leads to improved agreement with the observed pattern of changes over the northern continents and reduces the global mean warming by about 30%. Doubling the aerosol forcing produces patterns that are still compatible with the observations, but further increase leads to unrealistically extensive cooling in the midlatitudes. The diurnal range of surface temperature decreases over most of the northern extratropics on increasing CO{sub 2}, in agreement with recent observations. The addition of the current industrial aerosol had little detectable effect on the diurnal range in the model because the direct effect of reduced solar heating at the surface is approximately balanced by the indirect effects of cooling. Thus, the ratio of the reduction in diurnal range to the mean warming is increased, in closer agreement with observations. Results from further sensitivity experiments with larger increases in aerosol and CO{sub 2} are presented.

Mitchell, J.F.B.; Davis, R.A.; Ingram, W.J.; Senior, C.A. [Hadley Centre for Climate Prediction and Research, Berkshire (United Kingdom)] [Hadley Centre for Climate Prediction and Research, Berkshire (United Kingdom)

1995-10-01T23:59:59.000Z

423

Chemical Safety Program  

NLE Websites -- All DOE Office Websites (Extended Search)

Program Program Home Chemical Safety Topical Committee Library Program Contacts Related Links Site Map Tools 2013 Chemical Safety Workshop Archived Workshops Contact Us Health and Safety HSS Logo Chemical Safety Program logo The Department of Energy's (DOE's) Chemical Safety web pages provide a forum for the exchange of best practices, lessons learned, and guidance in the area of chemical management. This page is supported by the Chemical Safety Topical Committee which was formed to identify chemical safety-related issues of concern to the DOE and pursue solutions to issues identified. Noteworthy products are the Chemical Management Handbooks and the Chemical Lifecycle Cost Analysis Tool, found under the TOOLS menu. Chemical Management Handbook Vol (1) Chemical Management Handbook Vol (2)

424

Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant  

NLE Websites -- All DOE Office Websites (Extended Search)

Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant Particles Title Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant Particles Publication Type Journal Article LBNL Report Number LBNL-42414 Year of Publication 2001 Authors Modera, Mark P., Olivier Brzozowski, François Rémi Carrié, Darryl J. Dickerhoff, William W. Delp, William J. Fisk, Ronnen M. Levinson, and Duo Wang Journal Energy & Buildings Volume 34 Start Page Chapter Pagination 705-714 Abstract Electricity energy savings potential by eliminating air leakage from ducts in large commercial buildings is on the order of 10 kWh/m2 per year (1 kWh/ft2). We have tested, in two large commercial buildings, a new technology that simultaneously seals duct leaks and measures effective leakage area of ducts. The technology is based upon injecting a fog of aerosolized sealant particles into a pressurized duct system. In brief, this process involves blocking all of the intentional openings in a duct system (e.g., diffusers). Therefore, when the system is pressurized, the only place for the air carrying the aerosol particles to exit the system is through the leaks. The key to the technology is to keep the particles suspended within the airstream until they reach the leaks, and then to have them leave the airstream and deposit on the leak sites. The principal finding from this field study was that the aerosol technology is capable of sealing the leaks in a large commercial building duct system within a reasonable time frame. In the first building, 66% of the leakage area was sealed within 2.5 hours of injection, and in the second building 86% of the leakage area was sealed within 5 hours. We also found that the aerosol could be blown through the VAV boxes in the second building without impacting their calibrations or performance. Some remaining questions are (1) how to achieve sealing rates comparable to those experienced in smaller residential systems; and (2) what tightness level these ducts systems can be brought to by means of aerosol sealing.

425

Thermophoretic separation of aerosol particles from a sampled gas stream  

DOE Patents (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

426

Final Project Report - ARM CLASIC CIRPAS Twin Otter Aerosol  

SciTech Connect

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

427

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

428

Chemical Management Contacts  

Energy.gov (U.S. Department of Energy (DOE))

Contacts for additional information on Chemical Management and brief description on Energy Facility Contractors Group

429

About Chemical Hazards  

NLE Websites -- All DOE Office Websites (Extended Search)

Chemical Hazards Chemical Hazards What Is a Chemical Hazard? chemical hazards.jpg A chemical hazard is any substance that can cause harm, primarily to people. Chemicals of all kinds are stored in our homes and can result in serious injuries if not properly handled. Household items such as bleach can result in harmful chlorine gas or hydrochloric acid if carelessly used. Gasoline fumes from containers for lawnmowers or boats can result in major health hazards if inhaled. DOE Oak Ridge uses thousands of chemicals in its varied research and other operations. New chemicals are or can be created as a result of the research or other activities. DOE follows national safety requirements in storing and handling these chemicals to minimize the risk of injuries from its chemical usage. However, accidents can occur despite careful attention to proper handling and storage procedures.

430

Long-term Statistics of Continental Cumuli: Does Aerosol Trigger Cumulus Variability?  

SciTech Connect

Atmospheric aerosols may control the formation, maintenance, and dissipation of cumuli by changing their microphysics. Recent observational and modeling results exist both in support and against strong potential impacts of aerosol [1-3]. Typically, the aerosol impact on water clouds has been investigated for regions with high aerosol loading and/or large atmospheric moisture [4]. Can we provide observational evidence of the aerosol-cloud relationship for a relatively dry continental region with low/moderate aerosol burden? To address this question, we revisit the aerosol-cloud relationship at the Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) Southern Great Plains (SGP) site. In comparison with highly polluted regions, the SGP site is characterized by relatively small-to-moderate aerosol loading. Also, moisture content is small-to-moderate (compared to marine and coastal regions) for the SGP site. Because cumulus clouds have important impacts on climate forcing estimations [5] and are susceptible to aerosol effects [6], we focus on fair-weather cumuli (FWC) and their association with aerosol concentration and other potentially important factors. This association is investigated using a new 8-year aerosol and cloud climatology (2000-2007) developed with collocated and coincident surface and satellite observations.

Kassianov, Evgueni I.; Berg, Larry K.; McFarlane, Sally A.; Flynn, Connor J.; Turner, David D.

2009-02-01T23:59:59.000Z

431

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

E-Print Network (OSTI)

, troposphere · Modification of cloud physical properties - hydrology and climate · Modification of fog, cloud

Schwartz, Stephen E.

432

Chemical Analysis and Ecohydrological Effects of Aerosols in a Costa Rican Tropical Forest  

E-Print Network (OSTI)

frequency and duration. They are less abundant at lower elevations where water deficiency is a limiting (La Bastille and Poole, 1978; Stadmuller, 1987; Hemp, 2010; Zadroga, 1981). This altitudinal Conservation Monitoring Centre (UNEP-WCMC), there are 477 cloud forest sites found in 62 countries. Costa Rica

433

The impact of meteorological conditions and variation in chemical composition of aerosols on regional cloud formation  

E-Print Network (OSTI)

Snyder, J.J. Schauer, R.E. Peltier, R.J. Weber, S.M. Murphy,Hecobian, O. Vargas, R.E. Peltier, A.T.C. Hanks, L.G. Huey,A.M. Middlebrook, R.E. Peltier, A. Sullivan, D.S. Thomson,

Creamean, Jessie Marie

2012-01-01T23:59:59.000Z

434

Toward a new chemical mechanism in WRF/Chem for direct and indirect aerosol  

E-Print Network (OSTI)

, University of Colorado at Boulder, Boulder, Colorado, USA. 3 Earth System Research Laboratory, National Oceanic and Atmospheric administration, Boulder, Colorado, USA. e-mail: paolo to the coarse resolution of the inventory and by the missing of wildfire emissions. The modeled concentration

Curci, Gabriele

435

Bringing the ocean into the laboratory to probe the chemical complexity of sea spray aerosol  

Science Journals Connector (OSTI)

...dDepartment of Atmospheric Science, Colorado State University, Fort Collins...anddDepartment of Atmospheric Science, Colorado State University, Fort Collins...the oceans, deserts, and wildfires, contribute 90% (mass/mass) to atmospheric...measurements were made using the Colorado State University continuous...

Kimberly A. Prather; Timothy H. Bertram; Vicki H. Grassian; Grant B. Deane; M. Dale Stokes; Paul J. DeMott; Lihini I. Aluwihare; Brian P. Palenik; Farooq Azam; John H. Seinfeld; Ryan C. Moffet; Mario J. Molina; Christopher D. Cappa; Franz M. Geiger; Gregory C. Roberts; Lynn M. Russell; Andrew P. Ault; Jonas Baltrusaitis; Douglas B. Collins; Craig E. Corrigan; Luis A. Cuadra-Rodriguez; Carlena J. Ebben; Sara D. Forestieri; Timothy L. Guasco; Scott P. Hersey; Michelle J. Kim; William F. Lambert; Robin L. Modini; Wilton Mui; Byron E. Pedler; Matthew J. Ruppel; Olivia S. Ryder; Nathan G. Schoepp; Ryan C. Sullivan; Defeng Zhao

2013-01-01T23:59:59.000Z

436

X-RAY ABSORPTION SPECTROSCOPY FOR THE CHEMICAL CHARACTERIZATION OF ATMOSPHERIC AEROSOLS  

E-Print Network (OSTI)

November 11-16 9 1979 X-RAY ABSORPTION SPECTROSCOPY FOR THEUniversity of California. ABSORPTION SPECTROSCOPY FOR THEand x-ray emission and absorption spectroscopy. The first

Jaklevic, J. M.

2011-01-01T23:59:59.000Z

437

Chemical Bonding and Structural Information of Black Carbon Reference Materials and Individual Carbonaceous Atmospheric Aerosols  

E-Print Network (OSTI)

anthropogenic combustion and biomass burns, thus allowingAnthropogenic combustion and biomass burn particles can befrom anthropogenic combustion and biomass burn sources are

Hopkins, Rebecca J.; Tivanski, Alexei V.; Marten, Bryan D.; Gilles, Mary K.

2007-01-01T23:59:59.000Z

438

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

E-Print Network (OSTI)

of potassium in biomass combustion, Proceedings of thethan those from biomass combustion. In Figure 3, ? ap valuesspectral dependence for the biomass combustion particulates.

2008-01-01T23:59:59.000Z

439

Atmospheric aerosols as prebiotic chemical reactors Christopher M. Dobson*, G. Barney Ellison  

E-Print Network (OSTI)

). It was long ago recognized that hot water or steam would have reacted with metal carbides to form hydrocarbons as prebiotic constituents by such means (7). Moreover, molecules of this type, including hydrocarbons

Ellison, Barney

440

Ground-truth aerosol lidar observations: can the Klett solutions obtained from ground and space be equal for the same aerosol case?  

Science Journals Connector (OSTI)

Upcoming multiyear satellite lidar aerosol observations need strong support by a worldwide ground-truth lidar network. In this context the question arises as to whether the ground...

Ansmann, Albert

2006-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

Bulk solubility and speciation of plutonium(VI) in phosphate-containing solutions  

SciTech Connect

The solubility and speciation of Pu(VI) with phosphate as a function of pH was investigated to determine the ability of phosphate to act as an actinide getter. The general properties were first investigated and are reported here with the goal of performing more quantitative experiments in the future. Solubility was approached from oversaturation at initial pH = 4, 10 and 13.4. Absorption spectra were recorded, the solution filtered and the filtrate counted. Absorption spectra were obtained at varying phosphate concentrations and at pH of 2.7 to 11.9. The effect of complexation on the 833 mn Pu(VI) band was characterized. Evidence for three phosphate complexes was obtained for pH < 10 which have absorption bands at 842, 846 and 849 mn. Evidence for colloid formation was observed but is not conclusive. The possibility of colloids prevents accurate analysis of the solubility experiments. A concentration of 10[sup [minus]5] to 10[sup [minus]6] M Pu(VI) was measured in the filtrate at pH [le] 10 that were passed through a 50 mn filter. Pu(VI) complexes with phosphate over hydroxide at pH [le] 11.6, but at pH [ge] 11.9, only hydrolyzed Pu(VI) was detected. At pH = 12, the concentration of Pu(VI) was as high as 10[sup [minus]4] M.

Weger, H.T.; Okajima, S.; Cunnane, J.C.; Reed, D.T.

1992-01-01T23:59:59.000Z

442

Bulk solubility and speciation of plutonium(VI) in phosphate-containing solutions  

SciTech Connect

The solubility and speciation of Pu(VI) with phosphate as a function of pH was investigated to determine the ability of phosphate to act as an actinide getter. The general properties were first investigated and are reported here with the goal of performing more quantitative experiments in the future. Solubility was approached from oversaturation at initial pH = 4, 10 and 13.4. Absorption spectra were recorded, the solution filtered and the filtrate counted. Absorption spectra were obtained at varying phosphate concentrations and at pH of 2.7 to 11.9. The effect of complexation on the 833 mn Pu(VI) band was characterized. Evidence for three phosphate complexes was obtained for pH < 10 which have absorption bands at 842, 846 and 849 mn. Evidence for colloid formation was observed but is not conclusive. The possibility of colloids prevents accurate analysis of the solubility experiments. A concentration of 10{sup {minus}5} to 10{sup {minus}6} M Pu(VI) was measured in the filtrate at pH {le} 10 that were passed through a 50 mn filter. Pu(VI) complexes with phosphate over hydroxide at pH {le} 11.6, but at pH {ge} 11.9, only hydrolyzed Pu(VI) was detected. At pH = 12, the concentration of Pu(VI) was as high as 10{sup {minus}4} M.

Weger, H.T.; Okajima, S.; Cunnane, J.C.; Reed, D.T.

1992-12-01T23:59:59.000Z

443

A XANES study of Cu speciation in high-temperature brines using synthetic fluid inclusions  

SciTech Connect

Cu K-edge X-ray absorption near edge structure (XANES) spectra were recorded from individual synthetic brine fluid inclusions as a function of temperature up to 500 C. The inclusions serve as sample cells for high-temperature spectroscopic studies of aqueous Cu-Cl speciation. Cu{sup +} and Cu{sup 2+} can both be identified from characteristic pre-edge features. Mixed oxidation states can be deconvoluted using linear combinations of Cu{sup +} and Cu{sup 2+} spectra. This work illustrates how complex Cu XANES spectra can be interpreted successfully. Cu{sup 2+} is the stable oxidation state in solution at room temperature and Cu{sup +} at high temperatures. The change in oxidation state with temperature was completely reversible. Cu{sup +} was found to occur exclusively as the linear species [CuCl{sub 2}]{sup -} in solutions containing KCl with Cu:Cl ratios up to 1:6. In the absence of K{sup +}, there is evidence for higher order coordination of Cu{sup +}, in particular the tetrahedral complex [CuCl{sub 4}]{sup 3-}. The importance of such complexes in natural ore-forming fluids is yet to be determined, but may explain the vapor-phase partitioning of Cu as a Cl complex from a Cl-rich brine.

Berry, Andrew J.; Hack, Alistair C.; Mavrogenes, John A.; Newville, Matthew; Sutton, Stephen R. (UC); (ANU)

2010-12-03T23:59:59.000Z

444

Release of aged contaminants from weathered sediments: Effects of sorbate speciation on scaling of reactive transport  

SciTech Connect

Hanford sediments impacted by hyperalkaline high level radioactive waste have undergone incongruent silicate mineral weathering concurrent with contaminant uptake. In this project, we studied the impact of background pore water (BPW) on strontium, cesium and iodine desorption and transport in Hanford sediments that were experimentally weathered by contact with simulated hyperalkaline tank waste leachate (STWL) solutions. Using those lab-weathered Hanford sediments (HS) and model precipitates formed during nucleation from homogeneous STWL solutions (HN), we (i) provided thorough characterization of reaction products over a matrix of field-relevant gradients in contaminant concentration, partial pressure of carbon dioxide, and reaction time; (ii) improved molecular-scale understanding of how sorbate speciation controls contaminant desorption from weathered sediments upon removal of caustic sources; and (iii) developed a mechanistic, predictive model of meso- to field-scale contaminant reactive transport under these conditions. In this final report, we provide detailed descriptions of our results from this three-year study, completed in 2012 following a one-year no cost extension.

Chorover, Jon; Perdrial, Nico; Mueller, Karl; Strepka, Caleb; OĂƒ ƒ Ă‚ Â˘Ăƒ ‚ Ă‚ € Ăƒ ‚ Ă‚ ™ Day, Peggy; Rivera, Nelson; Um, Wooyong; Chang, Hyun-Shik; Steefel, Carl; Thompson, Aaron

2012-11-05T23:59:59.000Z

445

Mn, Fe, Zn and As speciation in a fast-growing ferromanganese marine nodule  

SciTech Connect

The speciation of Mn, Fe, As and Zn in a fast-growing (0.02mm/yr), shallow-marine ferromanganese nodule has been examined by micro X-ray fluorescence, micro X-ray diffraction, and micro X-ray absorption spectroscopy. This nodule exhibits alternating Fe-rich and Mn-rich layers reflecting redox variations in water chemistry. Fe occurs as two-line ferrihydrite. The As is strictly associated with Fe and is mostly pentavalent, with an environment similar to that of As sorbed on or coprecipitated with synthetic ferrihydrite. The Mn is in the form of turbostratic birnessite with {approx} 10 percent trivalent manganese in the layers and probably {approx} 8 percent corner-sharing metal octahedra in the interlayers. The Zn is enriched on the rim of the nodule, associated with Mn. The Zn is completely (>90 percent) tetrahedrally coordinated and sorbed in the interlayers of birnessite on vacant layer Mn sites. The Zn and Mn species are similar to ones found in soils, suggesting common structural principles, despite the differing formation conditions in these systems.

Marcus, Matthew A.; Manceau, Alain; Kersten, Michael

2004-04-01T23:59:59.000Z

446

Relating Pore-Scale Uranium Aquatic Speciation to Intermediate-Scale Aquifer Heterogeneity  

SciTech Connect

The speciation and transport of uranium (VI) through porous media is highly dependent on solution conditions, the presence of complexing ligands, and the nature of the porous media. The dependency on many variables makes prediction of U transport in bench-scale experiments and in the field difficult. In particular, the identification of colloidal U phases poses a technical challenge. Transport of U in the presence and absence of natural organic matter (Suwannee River humic acid, SRHA) through silica sand and hematite coated silica sand was tested at pH 4 and 5 using static columns, where flow is controlled by gravity and residence time between advective pore volume exchanges can be strictly controlled. The column effluents were characterized by traditional techniques including ICPMS quantification of total [U] and [Fe], TOC analysis of [DOC], and pH analysis, and also by non-traditional techniques: flow field flow fractionation with online ICPMS detection (FlFFF-ICPMS) and specific UV absorbance (SUVA) characterization of effluent fractions. Key results include that the transport of U through the columns was enhanced by pre-equilibration with SRHA, and previously deposited U was remobilized by the addition of SRHA. The advanced techniques yielded important insights on the mechanisms of transport: FlFFF-ICPMS identified a U?SRHA complex as the mobile U species and directly quantified relative amounts of the complex, while specific UV absorbance (SUVA) measurements indicated a composition-based fractionation onto the porous media.

Ranville, James

2013-04-01T23:59:59.000Z

447

Sources and Composition of Submicron Organic Mass in Marine Aerosol Particles  

Recent studies have proposed a variety of interpretations of the sources and composition of atmospheric marine aerosol particles (aMAP) based on a range of physical and chemical measurements collected during open-ocean research cruises. To investigate the processes that affect marine organic particles, this study uses the characteristic functional group composition (from Fourier transform infrared (FTIR) spectroscopy) of aMAP from five ocean regions to show that: (i) The organic functional group composition of aMAP that can be identified as atmospheric primary marine (ocean-derived) aerosol (aPMA) is 65±12% hydroxyl, 21±9% alkane, 6±6% amine, and 7±8% carboxylic acid functional groups. Contributions from photochemical reactions add carboxylic acid groups (15%-25%), shipping effluent in seawater and ship emissions add additional alkane groups (up to 70%), and coastal emissions mix in alkane and carboxylic acid groups from coastal pollution sources. (ii) The organic composition of aPMA is nearly identical to model generated primary marine aerosol particles (gPMA) from bubbled seawater (55% hydroxyl, 32% alkane, and 13% amine functional groups), indicating that its overall functional group composition is the direct consequence of the organic constituents of the seawater source. (iii) While the seawater organic functional group composition was nearly invariant across all three ocean regions studied, the gPMA alkane group fraction increased with chlorophyll-a concentrations (r = 0.79). gPMA from productive seawater had a larger fraction of alkane functional groups (35%) compared to gPMA from non-productive seawater (16%), likely due to the presence of surfactants in productive seawater that stabilize the bubble film and lead to preferential drainage of the more soluble (lower alkane group fraction) organic components. gPMA has a hydroxyl group absorption peak location characteristic of monosaccharides and disaccharides, where the seawater OM hydroxyl group peak location is closer to that of polysaccharides. This may result from the larger saccharides preferentially remaining in the seawater during gPMA and aPMA production

Frossard, Amanda; Russell, Lynn; Burrows, Susannah M.; Elliott, Scott; Bates, Timothy S.; Quinn, P. K.

2014-11-27T23:59:59.000Z

448

Water content and morphology of sodium chloride aerosol particles  

E-Print Network (OSTI)

to explain the H2O content. The model in which the NaCl particles contain pockets of aqueous NaCl solution was found to be most consistent with the spectroscopic observations. The relevance of salt particle morphology and water content to atmospheric aerosol...

Weis, David D.; Ewing, George E.

1999-09-20T23:59:59.000Z

449

Soft ionization of thermally evaporated hypergolic ionic liquid aerosols  

SciTech Connect

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

450

Building America Webinar: Sealing of Home Enclosures with Aerosol Particles  

Energy.gov (U.S. Department of Energy (DOE))

This webinar was presented by research team Building Industry Research Alliance (BIRA), and provided information about a project that uses existing aerosol duct sealing technology to seal the entire building enclosure in order to achieve greater airtightness and energy and cost savings.

451

LESSONS LEARNED IN AEROSOL MONITORING WITH THE RASA  

SciTech Connect

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

452

An overview of geoengineering of climate using stratospheric sulphate aerosols  

Science Journals Connector (OSTI)

...prior to mixing with turbine bypass air, through...and infrastructure development effort needed to...sulphate aerosol strategy is imperfect. The...with greenhouse gases. Furthermore...reductions in greenhouse gas emissions must take...geoengineering mitigation strategy occurring in the...

2008-01-01T23:59:59.000Z

453

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

454

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

455

Correction to “Hyperspectral Aerosol Optical Depths from TCAP Flights”  

SciTech Connect

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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Tabulation of thermodynamic data for chemical reactions involving 58 elements common to radioactive waste package systems  

SciTech Connect

The rate of release and migration of radionuclides from a nuclear waste repository to the biosphere is dependent on chemical interactions between groundwater, the geologic host rock, and the radioactive waste package. For the purpose of this report, the waste package includes the wasteform, canister, overpack, and repository backfill. Chemical processes of interest include sorption (ion exchange), dissolution, complexation, and precipitation. Thermochemical data for complexation and precipitation calculations for 58 elements common to the radioactive waste package are presented. Standard free energies of formation of free ions, complexes, and solids are listed. Common logarithms of equilibrium constants (log K's) for speciation and precipitation reactions are listed. Unless noted otherwise, all data are for 298.15/sup 0/K and one atmosphere.

Benson, L.V.; Teague, L.S.

1980-08-01T23:59:59.000Z

457

Aerosol optical and hygroscopic properties during TexAQS-GoMACCS 2006 and their impact on aerosol  

E-Print Network (OSTI)

by diesel-fueled mobile sources and from the numerous coal- fired industries and power generation stations August thru 11 September 2006) with a number of gas and aerosol instru- ments deployed to measure air and power plants, with emissions rich in reactive volatile organic compounds (VOCs) and NOX [Ryerson et al

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Published: November 03, 2011 r 2011 American Chemical Society 1196 dx.doi.org/10.1021/ac201338x |Anal. Chem. 2012, 84, 11961201  

E-Print Network (OSTI)

) are formed from gas to particle conversion (nucleation), condensation of low volatility species, primary and secondary, is the complexity in their chemical composition. Another important feature (settling) is the sink process, whereas for small aerosols, coagulation is the major sink. An important

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Use of Micro-XANES to Speciate Chromium in Airborne Fine Particles  

E-Print Network (OSTI)

, and chemical industries, as well as combustion of fossil fuels, release both Cr(III) and Cr) in the atmosphere can lead to a wide array of negative health effects, the cause of toxicity is largely unknown. One aspect of PM that likely affects health is the chemical composition, in particular the transition metals

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

SciTech Connect

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

Note: This page contains sample records for the topic "aerosol chemical speciation" 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

Capacitive chemical sensor  

DOE Patents (OSTI)

A microfabricated capacitive chemical sensor can be used as an autonomous chemical sensor or as an analyte-sensitive chemical preconcentrator in a larger microanalytical system. The capacitive chemical sensor detects changes in sensing film dielectric properties, such as the dielectric constant, conductivity, or dimensionality. These changes result from the interaction of a target analyte with the sensing film. This capability provides a low-power, self-heating chemical sensor suitable for remote and unattended sensing applications. The capacitive chemical sensor also enables a smart, analyte-sensitive chemical preconcentrator. After sorption of the sample by the sensing film, the film can be rapidly heated to release the sample for further analysis. Therefore, the capacitive chemical sensor can optimize the sample collection time prior to release to enable the rapid and accurate analysis of analytes by a microanalytical system.

Manginell, Ronald P; Moorman, Matthew W; Wheeler, David R

2014-05-27T23:59:59.000Z

462

Chemicals from Metabolic Pathways  

Science Journals Connector (OSTI)

A few basic raw materials, petroleum, natural gas, +S from oil or natural gas, and O2 + N2 from air, generate first primary (or platform) chemicals, next secondary (commodity) chemicals, then intermediates, and f...

John Villadsen; Jens Nielsen; Gunnar Lidén

2011-01-01T23:59:59.000Z

463

Chemistry 455 Chemical Nanotechnology  

E-Print Network (OSTI)

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

Rohs, Remo

464

Chemicals and health  

Science Journals Connector (OSTI)

Chemicals and health ... I must add here that some chemicals are indeed dangerous in the environment, largely because they persist, they don't break down, and they can therefore build up in the food chain. ...

1980-11-03T23:59:59.000Z

465

Biobased Chemicals Without Biomass  

Science Journals Connector (OSTI)

Unlike most other companies using biology to make chemicals, LanzaTech does not rely on biomass feedstocks. ...

MELODY BOMGARDNER

2012-08-27T23:59:59.000Z

466

Mercury speciation driven by seasonal changes in a contaminated estuarine environment  

SciTech Connect

In this study, seasonal changes of mercury (Hg) species in the highly variable estuary of So?a/Isonzo River (northern Adriatic Sea) were investigated. Samplings were performed on a seasonal basis (September 2009, May, August and October 2010) and Hg species (total Hg, methylmercury (MeHg), dissolved gaseous Hg (DGM)) in waters, sediments and pore waters were determined. In addition, a range of ancillary parameters were measured (salinity, nutrients, organic carbon (OC), nitrogen species). Hg values were interpreted using these parameters and hydrological conditions (river flow, wave height) around the time of sampling. There were no significant changes in Hg load from river to the gulf, compared to previous studies. The load was temporarily higher in May 2010 due to higher river flow. Wave height, through changing hydrostatic pressure, was most likely to cause resuspension of already deposited Hg from the bottom (August 2010). The estuary is a net source of DGM to the atmosphere as suggested by DGM profiles, with salinity, redox potential and organic matter as the most probable controls over its production. MeHg is produced in situ in sediment or in water column, rather than transported by river, as indicated by its correlation with OC of the marine origin. Calculated fluxes for THg and MeHg showed sediment as a source for both the water column. In pore waters, OC in part affects partitioning of both THg and MeHg; however other factors (e.g. sulphide and/or oxyhydroxides precipitation and dissolution) are also probably important. -- Highlights: ? Water, sediment and pore water mercury species in front of So?a River estuary were measured. ? Seasonally variable hydrological conditions were shown to influence water column Hg speciation. ? Fluxes for total Hg and MeHg from sediment to water were calculated. ? Sediment is a source of total Hg and MeHg to the water column. ? Correlation of MeHg with organic carbon of marine origin suggests in situ formation.

Bratki?, Arne, E-mail: arne.bratkic@ijs.si [Department of Environmental Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)] [Department of Environmental Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Ogrinc, Nives, E-mail: nives.orginc@ijs.si [Department of Environmental Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)] [Department of Environmental Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Kotnik, Jože, E-mail: joze.kotnik@ijs.si [Department of Environmental Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)] [Department of Environmental Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Faganeli, Jadran, E-mail: faganeli@mbss.org [Marine Biology Station, Forna?e 41, 6330 Piran (Slovenia)] [Marine Biology Station, Forna?e 41, 6330 Piran (Slovenia); Žagar, Dušan, E-mail: dusan.zagar@fgg.uni-lj.si [Faculty of Civil and Geodetic Engineering, Jamova 2, 1000 Ljubljana (Slovenia)] [Faculty of Civil and Geodetic Engineering, Jamova 2, 1000 Ljubljana (Slovenia); Yano, Shinichiro [Faculty of Engineering, Kyushu University, Fukuoka 812-8581 (Japan)] [Faculty of Engineering, Kyushu University, Fukuoka 812-8581 (Japan); Tada, Akihide, E-mail: tada@civil.nagasaki-u.ac.jp [Faculty of Engineering, Nagasaki University, Bunkyo-machi 1-14, Nagasaki 852-8521 (Japan)] [Faculty of Engineering, Nagasaki University, Bunkyo-machi 1-14, Nagasaki 852-8521 (Japan); Horvat, Milena, E-mail: milena.horvat@ijs.si [Department of Environmental Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)] [Department of Environmental Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)

2013-08-15T23:59:59.000Z

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Correlation between speciated hydrocarbon emissions and flame ionization detector response for gasoline/alcohol blends .  

SciTech Connect

The U.S. renewable fuel standard has made it a requirement to increase the production of ethanol and advanced biofuels to 36 billion by 2022. Ethanol will be capped at 15 billion, which leaves 21 billion to come from other sources such as butanol. Butanol has a higher energy density and lower affinity for water than ethanol. Moreover, alcohol fueled engines in general have been shown to positively affect engine-out emissions of oxides of nitrogen and carbon monoxide compared with their gasoline fueled counterparts. In light of these developments, the variety and blend levels of oxygenated constituents is likely to increase in the foreseeable future. The effect on engine-out emissions for total hydrocarbons is less clear due to the relative insensitivity of the flame ionization detector (FID) toward alcohols and aldehydes. It is well documented that hydrocarbon (HC) measurement using a conventional FID in the presence of oxygenates in the engine exhaust stream can lead to a misinterpretation of HC emissions trends for alcohol fuel blends. Characterization of the exhaust stream for all expected hydrocarbon constituents is required to accurately determine the actual concentration of unburned fuel components in the exhaust. In addition to a conventional exhaust emissions bench, this characterization requires supplementary instrumentation capable of hydrocarbon speciation and response factor independent quantification. Although required for certification testing, this sort of instrumentation is not yet widely available in engine development facilities. Therefore, an attempt is made to empirically determine FID correction factors for oxygenate fuels. Exhaust emissions of an engine fueled with several blends of gasoline and ethanol, n-butanol and iso-Butanol were characterized using both a conventional FID and a Fourier transform infrared. Based on these results, a response factor predicting the actual hydrocarbon emissions based solely on FID results as a function of alcohol type and content is presented. Finally, the correlation derived from data presented in this study is compared with equations and results found in the literature.

Wallner, T. (Energy Systems)

2011-08-01T23:59:59.000Z

468

Institute of Chemical Engineering and High Temperature Chemical...  

Open Energy Info (EERE)

Chemical Processes ICEHT Jump to: navigation, search Name: Institute of Chemical Engineering and High Temperature Chemical Processes (ICEHT) Place: Hellas, Greece Zip:...

469

HARVARD UNIVERSITY CHEMICAL BIOLOGY  

E-Print Network (OSTI)

HARVARD UNIVERSITY CHEMICAL BIOLOGY PHD PROGRAM 2013-2014 Student Handbook #12;Program Contacts at the beginning of each semester. Laboratory Rotations Students in the Chemical Biology Program are expected an interest in having Chemical Biology Program Students in their labs. Students may rotate in the labs

Church, George M.

470

Computational Chemical Materials Engineering  

E-Print Network (OSTI)

: Thermal barrier coatings, wear resistance coatings, radiation resistant materials · Materials for opticalHome Computational Chemical and Materials Engineering Tahir Cagin Chemical Engineering Department to understand behavior and properties of materials as a function of ­ Chemical constitution ­ Composition

471

The AeroCom Evaluation and Intercomparison of Organic Aerosol in Global Models  

This paper evaluates the current status of global modeling of the organic aerosol (OA) occurrence in the troposphere and analyzes the differences calculated between models as well as between models and observations. Thirty-one global chemistry/transport and general circulation models have participated in this intercomparison, in the framework of AeroCom phase II. The simulation of OA varies greatly between models in terms of the magnitude of primary emissions, secondary OA (SOA) formation, the number of OA species used (2 to 62), the complexity of OA parameterizations (gas-particle partitioning, chemical aging, multiphase chemistry, aerosol microphysics), and the OA physical, chemical and optical properties. The diversity of the global OA simulation results has increased since earlier AeroCom experiments, mainly due to the increasing complexity of the SOA parameterization in models, and the implementation of new, highly uncertain, OA sources. Diversity of over an order of magnitude exists in the modeled vertical distribution of OA that deserves a dedicated future study. Furthermore, although the OA/OC ratio depends on OA sources and atmospheric processing and is important for model evaluation against OA and OC observations, it is resolved only by few global models. The median global primary OA source strength is 56 Tg a 1 (range 34 - 144 Tg a-1) and the median secondary OA source strength (natural and anthropogenic) is 19 Tg a-1 (range 13-121 Tg a-1). Among the models that take into account the semi-volatile SOA nature, the median source is calculated to be 51 Tg a-1 (range 16-121 Tg a-1), much larger than the median value of the models that calculate SOA in a more simplistic way (19 Tg a-1; range 13-20 Tg a-1, with one model at 37 Tg a-1). The median atmospheric burden of OA is 1.4 Tg (24 models in the range of 0.6-2.0 Tg and 4 between 2.4-3.8 Tg) with a median OA lifetime of 5.4 days (range 3.8-9.6 days). In models that reported both OA and sulfate burdens, the median value of the OA/sulfate burden ratio of is calculated to be 0.77; 13 models calculate a ratio lower than 1, and 9 models higher than 1. For 26 models that reported OA deposition fluxes, the median wet removal is 70 Tg a-1 (range 28-209 Tg a-1), which is on average 85% of the total OA deposition.

Tsigaridis, Kostas; Daskalakis, N.; Kanakidou, M.; Adams, P. J.; Artaxo, Paulo; Bahadur, R.; Balkanski, Y.; Bauer, S.; Bellouin, N.; Benedetti, Angela; Bergman, T.; Berntsen, T.; Beukes, J. P.; Bian, Huisheng; Carslaw, K. S.; Chin, M.; Curci, Gabriele; Diehl, Thomas; Easter, Richard C.; Ghan, Steven J.; Gong, S.; Hodzic, Alma; Hoyle, Christopher R.; Iversen, T.; Jathar, S.; Jimenez, J. L.; Kaiser, J. W.; Kirkevag, A.; Koch, Dorothy; Kokkola, H.; Lee, Y. H.; Lin, G.; Liu, Xiaohong; Luo, Gan; Ma, Xiaoyan; Mann, G. W.; Mihalopoulos, Nikos; Morcrette, J. -J.; Muller, J. F.; Myhre, G.; Myriokefalitakis, S.; Ng, Nga L.; O'Donell, D.; Penner, J. E.; Pozzoli, L.; Pringle, K. J.; Russell, Lynn; Schulz, M.; Sciare, J.; Seland, O.; Shindell, Drew; Sillman, S.; Skeie, R. B.; Spracklen, D. V.; Stavrakou, T.; Steenrod, Stephen D.; Takemura, T.; Tiitta, P.; Tilmes, S.; Tost, H.; van Noije, T.; van Zyl, P. G.; von Salzen, Knut; Yu, Fangqun; Wang, Zaizi; Wang, Zhilli; Zaveri, Rahul A.; Zhang, Hua; Zhang, Kai; Zhang, Qi; Zhang, Xiaoye

2014-10-15T23:59:59.000Z

472

An Observed Signature of Aerosol Effect on Cloud Droplet Radii from a  

NLE Websites -- All DOE Office Websites (Extended Search)

An Observed Signature of Aerosol Effect on Cloud Droplet Radii from a An Observed Signature of Aerosol Effect on Cloud Droplet Radii from a Decade of Observations at a Mid-Continental Site Min, Qilong State University of New York at Albany Duan, Minzheng State University of New York at Albany Harrison, Lee State University of New York Joseph, Everette Howard University Category: Aerosols Continuing observations of aerosol and cloud optical property have been made using MFRSR and MWR at the ARM SGP site since 1993. Diurnal, monthly, seasonal and interannual variability of aerosol (optical depth and Angstrom coefficient) and cloud (optical depth and effective radius) have been analyzed. We have correlated an "aerosol index" computed from clear-sky observations of MFRSR with cloud droplet mean effective radius to study the

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