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Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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.


1

ARM - Midlatitude Continental Convective Clouds - Ultra High Sensitivity Aerosol Spectrometer(tomlinson-uhsas)  

SciTech Connect (OSTI)

Ultra High Sensitivity Aerosol Spectrometer (UHSASA) A major component of the Mid-latitude Continental Convective Clouds Experiment (MC3E) field campaign was the deployment of an enhanced radiosonde array designed to capture the vertical profile of atmospheric state variables (pressure, temperature, humidity wind speed and wind direction) for the purpose of deriving the large-scale forcing for use in modeling studies. The radiosonde array included six sites (enhanced Central Facility [CF-1] plus five new sites) launching radiosondes at 3-6 hour sampling intervals. The network will cover an area of approximately (300)2 km2 with five outer sounding launch sites and one central launch location. The five outer sounding launch sites are: S01 Pratt, KS [ 37.7oN, 98.75oW]; S02 Chanute, KS [37.674, 95.488]; S03 Vici, Oklahoma [36.071, -99.204]; S04 Morris, Oklahoma [35.687, -95.856]; and S05 Purcell, Oklahoma [34.985, -97.522]. Soundings from the SGP Central Facility during MC3E can be retrieved from the regular ARM archive. During routine MC3E operations 4 radiosondes were launched from each of these sites (approx. 0130, 0730, 1330 and 1930 UTC). On days that were forecast to be convective up to four additional launches were launched at each site (approx. 0430, 1030, 1630, 2230 UTC). There were a total of approximately 14 of these high frequency launch days over the course of the experiment. These files contain brightness temperatures observed at Purcell during MC3E. The measurements were made with a 5 channel (22.235, 23.035, 23.835, 26.235, 30.000GHz) microwave radiometer at one minute intervals. The results have been separated into daily files and the day of observations is indicated in the file name. All observations were zenith pointing. Included in the files are the time variables base_time and time_offset. These follow the ARM time conventions. Base_time is the number seconds since January 1, 1970 at 00:00:00 for the first data point of the file and time_offset is the offset in seconds from base_time.

Tomlinson, Jason; Jensen, Mike

2012-02-28T23:59:59.000Z

2

Sensitivity of an underwater acoustic array to ultra-high energy neutrinos  

E-Print Network [OSTI]

the maximum energy of protons of cos- mological origin somewhere below 1020 eV, be- cause of the finite (%50Sensitivity of an underwater acoustic array to ultra-high energy neutrinos Nikolai G. Lehtinen the possibility of searching for ultra high energy neutrinos in cosmic rays using acoustic techniques in ocean

Buckingham, Michael

3

A Copper Crystal Lens for Ultra-High-Sensitivity Medical Imaging  

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

A Copper Crystal Lens for Ultra-High-Sensitivity Medical Imaging A Copper Crystal Lens for Ultra-High-Sensitivity Medical Imaging A copper crystal lens developed at the Advanced Photon Source represents a new and promising approach in nuclear medicine for imaging very small tumors in the human body with higher sensitivity and higher spatial resolution than the cameras now in use. Conceptual view of the 6-lens array system. This system would provide sufficient data to generate a 3-dimensional image of a tumor. Conceptual view of the 6-lens array system. This system would provide sufficient data to generate a 3-dimensional image of a tumor. The lens is designed to focus gamma-ray energies of 100 to 200 keV, which makes it ideal for focusing the 140.6-keV gamma rays from Technetium-99m typically used in radioactive tracers. This new approach to medical imaging

4

Ultra-high vacuum fabrication and electrical characterization of environmentally sensitive metal oxide semiconductor capacitors  

SciTech Connect (OSTI)

We describe an integrated, ultra-high vacuum system for metal oxide semiconductor (MOS) device fabrication and characterization. Such a system is advantageous for electrical property measurements of electronic devices consisting of environmentally sensitive materials especially as device dimensions approach the nanoscale. Without exposure to atomosphere, MOS capacitors were fabricated by evaporating gate metal on molecular-beam-epitaxy (MBE) grown dielectrics on 3 inch-diameter substrates through a shadow mask in a UHV electrode-patterning chamber. The finished device is transferred in vacuum to an in-situ, UHV electrical characterization probe station that was designed with standard UHV coaxial feedthroughs and UHV-compatible, Kapton-insulated coaxial cable. The probe station also includes a heated sample stage that allows for annealing and measurements in a controlled ambient. We obtained excellent agreement between air-ambient ex-situ and in-situ probe station measurements utilizing a capacitor standard compatible with UHV based on single crystal sapphire as the dielectric. The measurements show less than 0.3 % dispersion for frequencies from 20 Hz to 1 MHz. We have successfully measured MOS capacitors and are sensitive to a density of interface states of 1x1010 states cm-2 eV-1. These measurements also show 0.5 % dispersion for measurement frequencies from 20 Hz to 1 kHz and less than 0.1 % from 1 kHz to 1 MHz. The integrated system presented here is one where complex, MBE-grown MOS heterostructures can be synthesized and tested rapidly to elucidate new field-effect-device physics and functionality.

Billman, Curt [Oak Ridge National Laboratory (ORNL); Walker, Frederick Joseph [ORNL

2007-01-01T23:59:59.000Z

5

Vapor-deposited /sup 235/UO/sub 2/ layers for an ultra-high-sensitivity fission counter  

SciTech Connect (OSTI)

After evaluating the properties of uranium oxide coatings prepared by electrodeposition, painting and physical vapor deposition, the vapor deposition method was selected as being preferable for preparing coatings on aluminum electrodes having a total area of 5 m/sup 2/. The electrodes were used in an experimental fission chamber designed at the Oak Ridge National Laboratory for use as a neutron flux monitor the Clinch River Breeder Reactor. Initial testing of the Ultra-High Sensitivity Fission Counter (UHSFC) indicated that a tenfold increase in sensitivity was achieved as compared to commercially available fission counters. Techniques used in vapor coating and characterizing the /sup 235/UO/sub 2/ deposits on the large-area curved substrates are described.

Adair, H.L.; Byrum, B.L.; Dailey, J.M.; Gibson, J.R.

1982-01-01T23:59:59.000Z

6

Ultra high vacuum pumping system and high sensitivity helium leak detector  

DOE Patents [OSTI]

An improved helium leak detection method and apparatus are disclosed which increase the leak detection sensitivity to 10.sup.-13 atm cc s.sup.-1. The leak detection sensitivity is improved over conventional leak detectors by completely eliminating the use of o-rings, equipping the system with oil-free pumping systems, and by introducing measured flows of nitrogen at the entrances of both the turbo pump and backing pump to keep the system free of helium background. The addition of dry nitrogen flows to the system reduces backstreaming of atmospheric helium through the pumping system as a result of the limited compression ratios of the pumps for helium.

Myneni, Ganapati Rao (Yorktown, VA)

1997-01-01T23:59:59.000Z

7

Ultra high vacuum pumping system and high sensitivity helium leak detector  

DOE Patents [OSTI]

An improved helium leak detection method and apparatus are disclosed which increase the leak detection sensitivity to 10{sup {minus}13} atm cc/s. The leak detection sensitivity is improved over conventional leak detectors by completely eliminating the use of o-rings, equipping the system with oil-free pumping systems, and by introducing measured flows of nitrogen at the entrances of both the turbo pump and backing pump to keep the system free of helium background. The addition of dry nitrogen flows to the system reduces back streaming of atmospheric helium through the pumping system as a result of the limited compression ratios of the pumps for helium. 2 figs.

Myneni, G.R.

1997-12-30T23:59:59.000Z

8

Real-time, single-step bioassay using nanoplasmonic resonator with ultra-high sensitivity  

DOE Patents [OSTI]

A nanoplasmonic resonator (NPR) comprising a metallic nanodisk with alternating shielding layer(s), having a tagged biomolecule conjugated or tethered to the surface of the nanoplasmonic resonator for highly sensitive measurement of enzymatic activity. NPRs enhance Raman signals in a highly reproducible manner, enabling fast detection of protease and enzyme activity, such as Prostate Specific Antigen (paPSA), in real-time, at picomolar sensitivity levels. Experiments on extracellular fluid (ECF) from paPSA-positive cells demonstrate specific detection in a complex bio-fluid background in real-time single-step detection in very small sample volumes.

Zhang, Xiang; Ellman, Jonathan A; Chen, Fanqing Frank; Su, Kai-Hang; Wei, Qi-Huo; Sun, Cheng

2014-04-01T23:59:59.000Z

9

Singlet-Fission Sensitizers for Ultra-High Efficiency Excitonic Solar Cells: 15 August 2005 - 14 October 2008  

SciTech Connect (OSTI)

We have considered the potential benefits offered by using singlet fission sensitizers in photovoltaic cells and identified two key issues involved in the search for such sensitizers.

Michl, J.

2008-12-01T23:59:59.000Z

10

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.

11

A Numerical Sensitivity Study of Aerosol Influence on Immersion Freezing  

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

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

12

Ultra High Energy Cosmic Rays  

Science Journals Connector (OSTI)

We discuss briefly the phenomenon of the Ultra High Energy Cosmic Rays (UHECR) particles of energy approaching and exceeding 1011 GeV. The world experimental statistics contains a small number of events but their existence is a puzzle. Its solution may lead to exciting discoveries in high energy particle astrophysics as well as in particle physics and astronomy.

Todor Stanev

2004-01-01T23:59:59.000Z

13

Ultra High Temperature | Open Energy Information  

Open Energy Info (EERE)

Ultra High Temperature Ultra High Temperature Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Print PDF Sanyal Temperature Classification: Ultra High Temperature Dictionary.png Ultra High Temperature: No definition has been provided for this term. Add a Definition Sanyal Temp Classification This temperature scheme was developed by Sanyal in 2005 at the request of DOE and GEA, as reported in Classification of Geothermal Systems: A Possible Scheme. Extremely Low Temperature Very Low Temperature Low Temperature Moderate Temperature High Temperature Ultra High Temperature Steam Field Reservoir fluid greater than 300°C is considered by Sanyal to be "ultra high temperature". "Such reservoirs are characterized by rapid development of steam saturation in the reservoir and steam fraction in the mobile fluid phase upon

14

Sensitive glow discharge ion source for aerosol and gas analysis  

DOE Patents [OSTI]

A high sensitivity glow discharge ion source system for analyzing particles includes an aerodynamic lens having a plurality of constrictions for receiving an aerosol including at least one analyte particle in a carrier gas and focusing the analyte particles into a collimated particle beam. A separator separates the carrier gas from the analyte particle beam, wherein the analyte particle beam or vapors derived from the analyte particle beam are selectively transmitted out of from the separator. A glow discharge ionization source includes a discharge chamber having an entrance orifice for receiving the analyte particle beam or analyte vapors, and a target electrode and discharge electrode therein. An electric field applied between the target electrode and discharge electrode generates an analyte ion stream from the analyte vapors, which is directed out of the discharge chamber through an exit orifice, such as to a mass spectrometer. High analyte sensitivity is obtained by pumping the discharge chamber exclusively through the exit orifice and the entrance orifice.

Reilly, Peter T. A. (Knoxville, TN)

2007-08-14T23:59:59.000Z

15

Ultra-High Resolution Electron Microscopy for Catalyst Characterizatio...  

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

Ultra-High Resolution Electron Microscopy for Catalyst Characterization Ultra-High Resolution Electron Microscopy for Catalyst Characterization 2011 DOE Hydrogen and Fuel Cells...

16

Ultra High Efficiency Electric Motor Generator  

Science Journals Connector (OSTI)

The Ultra High Efficiency Electric Motor Generator is an exciting opportunity to leverage ... in green technology. Marand currently produces this motor/generator at our Moorabbin facility for application ... sola...

Jeff Brown

2012-01-01T23:59:59.000Z

17

Faculty Position in Ultra High Precision Robotics & Manufacturing  

E-Print Network [OSTI]

, manipulation and metrology systems targeting additive manufacturing; · New kinematics, quasi-perfect guidings, actuators, transmission systems, sensors and methods targeting ultra-high precision additive manufacturingFaculty Position in Ultra High Precision Robotics & Manufacturing at the Ecole Polytechnique

Candea, George

18

ARM - Measurement - Aerosol particle size distribution  

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

19

Astronomy with ultra high-energy particles  

E-Print Network [OSTI]

Recent measurements of the properties of cosmic rays above 10^17 eV are summarized and implications on our contemporary understanding of their origin are discussed. Cosmic rays with energies exceeding 10^20 eV have been measured, they are the highest-energy particles in the Universe. Particles at highest energies are expected to be only marginally deflected by magnetic fields and they should point towards their sources on the sky. Recent results of the Pierre Auger Observatory have opened a new window to the Universe - astronomy with ultra high-energy particles.

Joerg R. Hoerandel

2008-03-20T23:59:59.000Z

20

Ultra-high vacuum photoelectron linear accelerator  

DOE Patents [OSTI]

An rf linear accelerator for producing an electron beam. The outer wall of the rf cavity of said linear accelerator being perforated to allow gas inside said rf cavity to flow to a pressure chamber surrounding said rf cavity and having means of ultra high vacuum pumping of the cathode of said rf linear accelerator. Said rf linear accelerator is used to accelerate polarized or unpolarized electrons produced by a photocathode, or to accelerate thermally heated electrons produced by a thermionic cathode, or to accelerate rf heated field emission electrons produced by a field emission cathode.

Yu, David U.L.; Luo, Yan

2013-07-16T23:59:59.000Z

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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

Adjoint model sensitivities for aerosol health impacts analysis and decision support tools  

E-Print Network [OSTI]

attribution of PM2.5 related mortality From fossil fuel SO2 (25,638) From fossil fuel NOx (19,816) SourceAdjoint model sensitivities for aerosol health impacts analysis and decision support tools Daven K on impacts on human health - develop high-resolution maps of source influences - integrate results

Jacob, Daniel J.

22

The origin of ultra high energy cosmic rays  

E-Print Network [OSTI]

We briefly discuss some open problems and recent developments in the investigation of the origin and propagation of ultra high energy cosmic rays (UHECRs).

Pasquale Blasi

2005-12-16T23:59:59.000Z

23

Ultra-high Resolution Electron Microscopy for Catalyst Characterizatio...  

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

high Resolution Electron Microscopy for Catalyst Characterization Ultra-high Resolution Electron Microscopy for Catalyst Characterization 2009 DOE Hydrogen Program and Vehicle...

24

Ultra-High Resolution Electron Microscopy for Catalyst Characterizatio...  

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

High Resolution Electron Microscopy for Catalyst Characterization Ultra-High Resolution Electron Microscopy for Catalyst Characterization 2010 DOE Vehicle Technologies and Hydrogen...

25

Variable Temperature Ultra-High Vacuum Scanning Tunneling Microscope...  

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

Vacuum Scanning Tunneling Microscope The Omicron variable temperature ultra-high vacuum (UHV) scanning tunneling microscope (VTSTM) is designed to study the structure of both clean...

26

Multilayer ultra-high-temperature ceramic coatings  

DOE Patents [OSTI]

A coated carbon-carbon composite material with multiple ceramic layers to provide oxidation protection from ultra-high-temperatures, where if the carbon-carbon composite material is uninhibited with B.sub.4C particles, then the first layer on the composite material is selected from ZrB.sub.2 and HfB.sub.2, onto which is coated a layer of SiC coated and if the carbon-carbon composite material is inhibited with B.sub.4C particles, then protection can be achieved with a layer of SiC and a layer of either ZrB.sub.2 and HfB.sub.2 in any order.

Loehman, Ronald E. (Albuquerque, NM); Corral, Erica L. (Tucson, AZ)

2012-03-20T23:59:59.000Z

27

Ultra-high density diffraction grating  

SciTech Connect (OSTI)

A diffraction grating structure having ultra-high density of grooves comprises an echellette substrate having periodically repeating recessed features, and a multi-layer stack of materials disposed on the echellette substrate. The surface of the diffraction grating is planarized, such that layers of the multi-layer stack form a plurality of lines disposed on the planarized surface of the structure in a periodical fashion, wherein lines having a first property alternate with lines having a dissimilar property on the surface of the substrate. For example, in one embodiment, lines comprising high-Z and low-Z materials alternate on the planarized surface providing a structure that is suitable as a diffraction grating for EUV and soft X-rays. In some embodiments, line density of between about 10,000 lines/mm to about 100,000 lines/mm is provided.

Padmore, Howard A.; Voronov, Dmytro L.; Cambie, Rossana; Yashchuk, Valeriy V.; Gullikson, Eric M.

2012-12-11T23:59:59.000Z

28

The Pierre Auger Observatory: Perspectives on Ultra-High Energy  

E-Print Network [OSTI]

¨ue, Argentina Abstract The Pierre Auger Observatory for ultra-high energy cosmic rays is under constructionThe Pierre Auger Observatory: Perspectives on Ultra-High Energy Cosmic Rays Tiina Suomij¨arvi1 in Argentina. The Observatory will consist when completed of 1600 water Cerenkov tanks and 24 fluorescence

Paris-Sud XI, Université de

29

Sensitivity of Clear-Sky Diffuse Radiation to In Situ Aerosol Scattering Parameters  

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

Sensitivity of Clear-Sky Diffuse Radiation to In Situ Sensitivity of Clear-Sky Diffuse Radiation to In Situ Aerosol Scattering Parameters P. J. Ricchiazzi and C. Gautier University of California Santa Barbara, California Introduction Recent studies of clear-sky radiation indicate that current radiative transfer (RT) models underestimate atmospheric absorption when standard aerosol properties are used. This so-called clear-sky anomaly is manifested in predicted levels of diffuse radiation significantly below those observed at Southern Great Plains (SGP) and other sites in the continental United States (e.g., Halthore et al. 1998 GRL). Other observations at pristine sites do not show a discrepancy (Barnard and Powell 2001, 2001; Kato et al. 1997; Halthore 1998). These results may indicate that the clear-sky anomaly is only observed at sites

30

Muons of very and ultra-high energy cosmic rays  

Science Journals Connector (OSTI)

In many cosmic rays experiments at very and ultra-high energies, an excess of muons (including those of very high energy, >100 TeV) is observed that cannot ... compositions, and especially the observed excesses o...

A. G. Bogdanov; R. P. Kokoulin

2013-11-01T23:59:59.000Z

31

Design of wind turbines with Ultra-High Performance Concrete  

E-Print Network [OSTI]

Ultra-High Performance Concrete (UHPC) has proven an asset for bridge design as it significantly reduces costs. However, UHPC has not been applied yet to wind turbine technology. Design codes do not propose any recommendations ...

Jammes, Franois-Xavier

2009-01-01T23:59:59.000Z

32

Ultra-high energy cosmic rays, spiral galaxies and magnetars  

Science Journals Connector (OSTI)

......locations of the ultra-high energy Auger events with a well defined...all the 27 UHECR events with energies larger than 57 EeV detected...2004, 2008), operating in Argentina since 2004, is located at...exposure is independent of the energy of the detected events and......

G. Ghisellini; G. Ghirlanda; F. Tavecchio; F. Fraternali; G. Pareschi

2008-10-01T23:59:59.000Z

33

Retrieval of Aerosol Optical Depth in Vicinity of Broken Clouds from Reflectance Ratios: Sensitivity Study  

SciTech Connect (OSTI)

We conducted a sensitivity study to better understand the potential of a new method for retrieving aerosol optical depth (AOD) under partly cloudy conditions. This method exploits reflectance ratios in the visible spectral range and provides an effective way to avoid three-dimensional (3D) cloud effects. The sensitivity study is performed for different observational conditions and random errors in input data. The results of the sensitivity study suggest that this ratio method has the ability to detect clear pixels even in close proximity to clouds. Such detection does not require a statistical analysis of the two-dimensional (2D) horizontal distribution of reflected solar radiation, and thus it could be customized for operational retrievals. In comparison with previously suggested approaches, the ratio method has the capability to increase the "harvest" of clear pixels. Similar to the traditional Independent Pixel Approximation (IPA), the ratio method has a low computational cost for retrieving AOD. In contrast to the IPA method, the ratio method provides much more accurate estimations of the AOD values under broken cloud conditions: pixel-based and domain-averaged estimations of errors in AOD are about 25% and 10%, respectively. Finally, both the ratio-based cloud screening and the accuracy of domain-averaged ratio-based AOD values do not suffer greatly when 5% random errors are introduced in the reflectances.

Kassianov, Evgueni I.; Ovtchinnikov, Mikhail; Berg, Larry K.; McFarlane, Sally A.; Flynn, Connor J.

2009-09-01T23:59:59.000Z

34

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

35

Ultra-High Temperature Distributed Wireless Sensors  

SciTech Connect (OSTI)

Research was conducted towards the development of a passive wireless sensor for measurement of temperature in coal gasifiers and coal-fired boiler plants. Approaches investigated included metamaterial sensors based on guided mode resonance filters, and temperature-sensitive antennas that modulate the frequency of incident radio waves as they are re-radiated by the antenna. In the guided mode resonant filter metamaterial approach, temperature is encoded as changes in the sharpness of the filter response, which changes with temperature because the dielectric loss of the guided mode resonance filter is temperature-dependent. In the mechanically modulated antenna approach, the resonant frequency of a vibrating cantilever beam attached to the antenna changes with temperature. The vibration of the beam perturbs the electrical impedance of the antenna, so that incident radio waves are phase modulated at a frequency equal to the resonant frequency of the vibrating beam. Since the beam resonant frequency depends on temperature, a Doppler radar can be used to remotely measure the temperature of the antenna. Laboratory testing of the guided mode resonance filter failed to produce the spectral response predicted by simulations. It was concluded that the spectral response was dominated by spectral reflections of radio waves incident on the filter. Laboratory testing of the mechanically modulated antenna demonstrated that the device frequency shifted incident radio waves, and that the frequency of the re-radiated waves varied linearly with temperature. Radio wave propagation tests in the convection pass of a small research boiler plant identified a spectral window between 10 and 13 GHz for low loss propagation of radio waves in the interior of the boiler.

May, Russell; Rumpf, Raymond; Coggin, John; Davis, Williams; Yang, Taeyoung; O'Donnell, Alan; Bresnahan, Peter

2013-03-31T23:59:59.000Z

36

Microsoft PowerPoint - 15.1130_Jeff Baker_Final Ultra-High Efficiency...  

Office of Environmental Management (EM)

130Jeff BakerFinal Ultra-High Efficiency Commercial Buildings Microsoft PowerPoint - 15.1130Jeff BakerFinal Ultra-High Efficiency Commercial Buildings Microsoft PowerPoint -...

37

Magnetic horizons of ultra-high energy cosmic rays  

E-Print Network [OSTI]

The propagation of ultra-high energy cosmic rays in extragalactic magnetic fields can be diffusive, depending on the strength and properties of the fields. In some cases the propagation time of the particles can be comparable to the age of the universe, causing a suppression in the flux measured on Earth. In this work we use magnetic field distributions from cosmological simulations to assess the existence of a magnetic horizon at energies around 10$^{18}$ eV.

Batista, Rafael Alves

2014-01-01T23:59:59.000Z

38

Double Pair Production by Ultra High Energy Cosmic Ray Photons  

E-Print Network [OSTI]

With use of CompHEP package we've made the detailed estimate of the influence of double e+e- pair production by photons (DPP) on the propagation of ultra high energy electromagnetic cascade. We show that in the models in which cosmic ray photons energy reaches few thousand EeV refined DPP analysis may lead to substantial difference in predicted photon spectrum compared to previous rough estimates.

S. V. Demidov; O. E. Kalashev

2008-12-22T23:59:59.000Z

39

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

E-Print Network [OSTI]

geoengineering with black carbon (BC) aerosols using a general circulation model with fixed sea surface would enhance the Arctic ozone hole. Using diesel fuel to produce the aerosols is likely prohibitively. Engineered particles, such as resonant scatterers or self-levitating particles, have been proposed

40

Ultra High-Rate Germanium (UHRGe) Modeling Status Report  

SciTech Connect (OSTI)

The Ultra-High Rate Germanium (UHRGe) project at Pacific Northwest National Laboratory (PNNL) is conducting research to develop a high-purity germanium (HPGe) detector that can provide both the high resolution typical of germanium and high signal throughput. Such detectors may be beneficial for a variety of potential applications ranging from safeguards measurements of used fuel to material detection and verification using active interrogation techniques. This report describes some of the initial radiation transport modeling efforts that have been conducted to help guide the design of the detector as well as a description of the process used to generate the source spectrum for the used fuel application evaluation.

Warren, Glen A.; Rodriguez, Douglas C.

2012-06-07T23:59:59.000Z

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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

Ultra high vacuum broad band high power microwave window  

DOE Patents [OSTI]

An improved high vacuum microwave window has been developed that utilizes high density polyethylene coated on two sides with SiOx, SiNx, or a combination of the two. The resultant low dielectric and low loss tangent window creates a low outgassing, low permeation seal through which broad band, high power microwave energy may be passed. No matching device is necessary and the sealing technique is simple. The features of the window are broad band transmission, ultra-high vacuum compatibility with a simple sealing technique, low voltage standing wave ratio, high power transmission and low cost.

Nguyen-Tuong, Viet (Seaford, VA); Dylla, III, Henry Frederick (Yorktown, VA)

1997-01-01T23:59:59.000Z

42

Ultra high vacuum broad band high power microwave window  

DOE Patents [OSTI]

An improved high vacuum microwave window has been developed that utilizes high density polyethylene coated on two sides with SiOx, SiNx, or a combination of the two. The resultant low dielectric and low loss tangent window creates a low outgassing, low permeation seal through which broad band, high power microwave energy may be passed. No matching device is necessary and the sealing technique is simple. The features of the window are broad band transmission, ultra-high vacuum compatibility with a simple sealing technique, low voltage standing wave ratio, high power transmission and low cost. 5 figs.

Nguyen-Tuong, V.; Dylla, H.F. III

1997-11-04T23:59:59.000Z

43

Wide band cryogenic ultra-high vacuum microwave absorber  

DOE Patents [OSTI]

An absorber wave guide assembly for absorbing higher order modes of microwave energy under cryogenic ultra-high vacuum conditions, that absorbs wide-band multi-mode energy. The absorber is of a special triangular shape, made from flat tiles of silicon carbide and aluminum nitride. The leading sharp end of the absorber is located in a corner of the wave guide and tapers to a larger cross-sectional area whose center is located approximately in the center of the wave guide. The absorber is relatively short, being of less height than the maximum width of the wave guide.

Campisi, Isidoro E. (Newport News, VA)

1992-01-01T23:59:59.000Z

44

Wide band cryogenic ultra-high vacuum microwave absorber  

DOE Patents [OSTI]

An absorber waveguide assembly for absorbing higher order modes of microwave energy under cryogenic ultra-high vacuum conditions, that absorbs wide-band multi-mode energy. The absorber is of a special triangular shape, made from flat tiles of silicon carbide and aluminum nitride. The leading sharp end of the absorber is located in a corner of the waveguide and tapers to a larger cross-sectional area whose center is located approximately in the center of the wave guide. The absorber is relatively short, being of less height than the maximum width of the waveguide. 11 figs.

Campisi, I.E.

1992-05-12T23:59:59.000Z

45

Radiative Effects of Dust Aerosols, Natural Cirrus Clouds and Contrails: Broadband Optical Properties and Sensitivity Studies  

E-Print Network [OSTI]

This dissertation aims to study the broadband optical properties and radiative effects of dust aerosols and ice clouds. It covers three main topics: the uncertainty of dust optical properties and radiative effects from the dust particle shape...

Yi, Bingqi

2013-07-09T23:59:59.000Z

46

Ultra-high pressure water jet: Baseline report  

SciTech Connect (OSTI)

The ultra-high pressure waterjet technology was being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU`s evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The ultra-high pressure waterjet technology acts as a cutting tool for the removal of surface substrates. The Husky{trademark} pump feeds water to a lance that directs the high pressure water at the surface to be removed. The safety and health evaluation during the testing demonstration focused on two main areas of exposure. These were dust and noise. The dust exposure was found to be minimal, which would be expected due to the wet environment inherent in the technology, but noise exposure was at a significant level. Further testing for noise is recommended because of the outdoor environment where the testing demonstration took place. In addition, other areas of concern found were arm-hand vibration, ergonomics, heat stress, tripping hazards, electrical hazards, lockout/tagout, fall hazards, slipping hazards, hazards associated with the high pressure water, and hazards associated with air pressure systems.

NONE

1997-07-31T23:59:59.000Z

47

Ultra-high energy cosmic rays from Quark Novae  

E-Print Network [OSTI]

We explore acceleration of ions in the Quark Nova (QN) scenario, where a neutron star experiences an explosive phase transition into a quark star (born in the propeller regime). In this picture, two cosmic ray components are isolated: one related to the randomized pulsar wind and the other to the propelled wind, both boosted by the ultra-relativistic Quark Nova shock. The latter component acquires energies $10^{15} {\\rm eV}wind, achieves ultra-high energies $E> 10^{18.6}$ eV. The composition is dominated by ions present in the pulsar wind in the energy range above $10^{18.6}$ eV, while at energies below $10^{18}$ eV the propelled ejecta, consisting of the fall-back neutron star crust material from the explosion, is the dominant one. Added to these two components, the propeller injects relativistic particles with Lorentz factors $\\Gamma_{\\rm prop.} \\sim 1-1000$, later to be accelerated by galactic supernova shocks. The QN model appears to be able to account for the extragalactic cosmic rays above the ankle and to contribute a few percent of the galactic cosmic rays below the ankle. We predict few hundred ultra-high energy cosmic ray events above $10^{19}$ eV for the Pierre Auger detector per distant QN, while some thousands are predicted for the proposed EUSO and OWL detectors.

R. Ouyed; P. Kernen; J. Maalampi

2003-01-29T23:59:59.000Z

48

Sensitivity of global-scale climate change attribution results to inclusion of fossil fuel black carbon aerosol - article no. L14701  

SciTech Connect (OSTI)

It is likely that greenhouse gas emissions caused most of the global mean warming observed during the 20th century, and that sulphate aerosols counteracted this warming to some extent, by reflecting solar radiation to space and thereby cooling the planet. However, the importance of another aerosol, namely black carbon, could be underestimated. Here we include fossil fuel black carbon aerosol in a detection and attribution analysis with greenhouse gas and sulphate aerosols. We find that most of the warming of the 20th Century is attributable to changes in greenhouse gases offset by net aerosol cooling. However the pattern of temperature change due to black carbon is currently indistinguishable from the sulphate aerosol pattern of temperature change. The attribution of temperature change due to greenhouse gases is not sensitive to the inclusion of black carbon. We can be confident about the overall attribution of total aerosols, but less so about the contributions of black carbon emissions to 20th century climate change. This work presents no evidence that black carbon aerosol forcing outweighed the cooling due to sulphate aerosol.

Jones, G.S.; Jones, A.; Roberts, D.L.; Stott, P.A.; Williams, K.D. [Hadley Center for Climate Predictions & Research, Exeter (United Kingdom)

2005-07-16T23:59:59.000Z

49

Ultra-high energy cosmic ray investigations by means of EAS muon density measurements  

E-Print Network [OSTI]

A new approach to investigations of ultra-high energy cosmic rays based on the ground-level measurements of the spectra of local density of EAS muons at various zenith angles is considered. Basic features of the local muon density phenomenology are illustrated using a simple semi-analytical model. It is shown that muon density spectra are sensitive to the spectrum slope, primary composition, and to the features of hadronic interaction. New experimental data on muon bundles at zenith angles from 30 degrees to horizon obtained with the coordinate detector DECOR are compared with CORSIKA-based simulations. It is found that measurements of muon density spectra in inclined EAS give possibility to study characteristics of primary cosmic ray flux in a very wide energy range from 10^15 to 10^19 eV.

N. S. Barbashina; A. G. Bogdanov; D. V. Chernov; A. N. Dmitrieva; D. M. Gromushkin; V. V. Kindin; R. P. Kokoulin; K. G. Kompaniets; G. Mannocchi; A. A. Petrukhin; O. Saavedra; V. V. Shutenko; D. A. Timashkov; G. Trinchero; I. I. Yashin

2007-01-11T23:59:59.000Z

50

Instrument Series: Microscopy Ultra-High Vacuum, Low- Temperature Scanning  

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

Low- Low- Temperature Scanning Probe Microscope EMSL's ultra-high vacuum, low-temperature scanning probe microscope instrument, or UHV LT SPM, is the preeminent system dedicated to surface chemistry and physics at low temperatures down to 5 K. Operating at low temperatures provides high mechanical stability, superior vacuum conditions, and negligible drift for long-term experiments. With thermal diffusion being entirely suppressed, stable imaging becomes possible even for weakly bound species. The system is primarily used for probing single-site chemical reactivity, while the combination with a hyperthermal molecular beam allows the study of important chemical processes at energies corresponding to the operational temperatures well beyond typical UHV studies. The LT SPM provides

51

Ultra-high-speed optical and electronic distributed devices  

SciTech Connect (OSTI)

This report summarizes work on the development of ultra-high-speed semiconductor optical and electronic devices. High-speed operation is achieved by velocity matching the input stimulus to the output signal along the device`s length. Electronic devices such as field-effect transistors (FET`s), should experience significant speed increases by velocity matching the electrical input and output signals along the device. Likewise, optical devices, which are typically large, can obtain significant bandwidths by velocity matching the light being generated, detected or modulated with the electrical signal on the device`s electrodes. The devices discussed in this report utilize truly distributed electrical design based on slow-wave propagation to achieve velocity matching.

Hietala, V.M.; Plut, T.A.; Kravitz, S.H.; Vawter, G.A.; Wendt, J.R.; Armendariz, M.G.

1995-08-01T23:59:59.000Z

52

Ultra-high pressure water jet: Baseline report; Summary  

SciTech Connect (OSTI)

The Husky{trademark} is an ultra high pressure waterjet cutting tool system. The pump is mounted on a steel tube frame which includes slots for transport by a forklift. The Husky{trademark} features an automatic shutdown for several conditions such as low oil pressure and high oil temperature. Placement of the Husky{trademark} must allow for a three foot clearance on all sides for operation and service access. At maximum continuous operation, the output volume is 7.2 gallons per minute with an output pressure of 40,000 psi. A diesel engine provides power for the system. The safety and health evaluation during the human factors assessment focused on two main areas: noise and dust.

NONE

1997-07-31T23:59:59.000Z

53

Ultra-high-ohmic microstripline resistors for Coulomb blockade devices  

Science Journals Connector (OSTI)

In this paper, we report on the fabrication and low-temperature characterization of ultra-high-ohmic microstripline resistors made of a thin film of weakly oxidized titanium. Nearly linear voltagecurrent characteristics were measured at temperatures down to T~20mK for films with sheet resistivities as high as ~7k?, i.e.about an order of magnitude higher than our previous findings for weakly oxidized Cr. Our analysis indicates that such an improvement can help to create an advantageous high-impedance environment for different Coulomb blockade devices. Further properties of the Ti film addressed in this work show the promise of low-noise behavior of the resistors when applied in different realizations of the quantum standard of current.

Sergey V Lotkhov

2013-01-01T23:59:59.000Z

54

Ultra High-Resolution Global Climate Simulation Project PRINCIPAL INVESTIGATOR: James J. Hack  

E-Print Network [OSTI]

changes in the frequency and intensity of extreme events. This project is developing the scientific a terrestrial carbon modeling capabil- ity. #12;Ultra High-Resolution Global Climate Simulation Project elersUltra High-Resolution Global Climate Simulation Project PRINCIPAL INVESTIGATOR: James J. Hack

55

Polyhedral Specular Reflector Design for Ultra-High Spectrum Splitting Solar Module Efficiencies (>50%)  

E-Print Network [OSTI]

Polyhedral Specular Reflector Design for Ultra-High Spectrum Splitting Solar Module Efficiencies., Pasadena, CA, USA 95555-0345 ABSTRACT One pathway to achieving ultra-high solar efficiencies (>50, multijunction solar cell, solar concentrator 1. INTRODUCTION Solar cell efficiency is increased through

Atwater, Harry

56

17 March 2009 Do some ultra-high-energy cosmic rays originate in  

E-Print Network [OSTI]

17 March 2009 Do some ultra-high-energy cosmic rays originate in higher-dimensional space-time? Abstract I speculate that some ultra-high-energy cosmic rays may originate in another universe in flat (non have needed an initial energy of 500 EeV to arrive at earth with 320 EeV. If it originated farther out

Bryan, Ronald

57

ULTRA HIGH ENERGY COSMIC RAY SPECTRUM Baltrusaitis, R.M., Cady7  

E-Print Network [OSTI]

., Steck, D. Department of Physics, University of Utah, Salt Lake City, UT 84112 ABSTRACT Ultra-high energy and is essentially model independent. Shown in Fig. 1 is the raw energy distribution of observed events. #12;2.94 ± 0OG 5.1-2 146 ULTRA HIGH ENERGY COSMIC RAY SPECTRUM Baltrusaitis, R.M., Cady7 , R., Cassiday, G

58

RAIN AND WIND ESTIMATION FROM SEAWINDS IN HURRICANES AT ULTRA HIGH RESOLUTION  

E-Print Network [OSTI]

function (GMF) which relates wind to backscatter (0 ) is not well understood for extremely high wind speedsRAIN AND WIND ESTIMATION FROM SEAWINDS IN HURRICANES AT ULTRA HIGH RESOLUTION Brent A. Williams method for estimating wind and rain in hurricanes from SeaWinds at ultra-high resolution is developed. We

Long, David G.

59

Ultra-high-energy debris from the collisional Penrose process  

E-Print Network [OSTI]

Soon after the discovery of the Kerr metric, Penrose realized that superradiance can be exploited to extract energy from black holes. The original idea (involving the breakup of a single particle) yields only modest energy gains. A variant of the Penrose process consists of particle collisions in the ergoregion. The collisional Penrose process has been explored recently in the context of dark matter searches, with the conclusion that the ratio $\\eta$ between the energy of post-collision particles detected at infinity and the energy of the colliding particles should be modest ($\\eta \\lesssim 1.5$). Schnittman has shown that these studies underestimated the maximum efficiency by about one order of magnitude (i.e., $\\eta \\lesssim 15$). In this work we reach an even more striking conclusion: particle collisions in the vicinity of rapidly rotating black holes can result in arbitrarily high efficiencies. The astrophysical likelihood of these events deserves further scrutiny, but our study hints at the tantalizing possibility that the collisional Penrose process may power gamma rays and ultra-high-energy cosmic rays.

Emanuele Berti; Richard Brito; Vitor Cardoso

2014-10-30T23:59:59.000Z

60

Ultra-High Gradient Dielectric Wakefield Accelerator Experiments  

SciTech Connect (OSTI)

Ultra-high gradient dielectric wakefield accelerators are a potential option for a linear collider afterburner since they are immune to the ion collapse and electron/positron asymmetry problems implicit in a plasma based afterburner. The first phase of an experiment to study the performance of dielectric Cerenkov wakefield accelerating structures at extremely high gradients in the GV/m range has been completed. The experiment took advantage of the unique SLAC FFTB electron beam and its ultra-short pulse lengths and high currents (e.g., {sigma}{sub z} = 20 {micro}m at Q = 3 nC). The FFTB electron beam was successfully focused down and sent through short lengths of fused silica capillary tubing (ID = 200 {micro}m/OD = 325 {micro}m). The pulse length of the electron beam was varied to produce a range of electric fields between 2 and 20 GV/m at the inner surface of the dielectric tubes. We observed a sharp increase in optical emissions from the capillaries in the middle part of this surface field range which we believe indicates the transition between sustainable field levels and breakdown. If this initial interpretation is correct, the surfaced fields that were sustained equate to on axis accelerating field of several GV/m. In future experiments being developed for the SLAC SABER and BNL ATF we plan to use the coherent Cerenkov radiation emitted from the capillary tube as a field strength diagnostic and demonstrate GV/m range particle energy gain.

Thompson, M C; Badakov, H; Rosenzweig, J B; Travish, G; Hogan, M; Ischebeck, R; Kirby, N; Siemann, R; Walz, D; Muggli, P; Scott, A; Yoder, R

2006-08-04T23:59:59.000Z

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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

Ultra-High Gradient Dielectric Wakefield Accelerator Experiments  

SciTech Connect (OSTI)

Ultra-high gradient dielectric wakefield accelerators are a potential option for a linear collider afterburner since they are immune to the ion collapse and electron/positron asymmetry problems implicit in a plasma based afterburner. The first phase of an experiment to study the performance of dielectric Cerenkov wakefield accelerating structures at extremely high gradients in the GV/m range has been completed. The experiment took advantage of the unique SLAC FFTB electron beam and its ultra-short pulse lengths and high currents (e.g., {sigma}z = 20 {mu}m at Q = 3 nC). The FFTB electron beam was successfully focused down and sent through short lengths of fused silica capillary tubing (ID = 200 {mu}m / OD = 325 {mu}m). The pulse length of the electron beam was varied to produce a range of electric fields between 2 and 20 GV/m at the inner surface of the dielectric tubes. We observed a sharp increase in optical emissions from the capillaries in the middle part of this surface field range which we believe indicates the transition between sustainable field levels and breakdown. If this initial interpretation is correct, the surfaced fields that were sustained equate to on axis accelerating field of several GV/m. In future experiments being developed for the SLAC SABER and BNL ATF we plan to use the coherent Cerenkov radiation emitted from the capillary tube as a field strength diagnostic and demonstrate GV/m range particle energy gain.

Thompson, M. C. [Lawrence Livermore National Laboratory, Livermore, California, 90095 (United States); Badakov, H.; Rosenzweig, J. B.; Travis, G. [UCLA Department of Physics and Astronomy, Los Angeles, California, 90095 (United States); Hogan, M.; Ischebeck, R.; Kirby, N.; Siemann, R.; Walz, D. [Stanford Linear Accelerator Center, Stanford, California, 94309 (United States); Muggli, P. [University of Southern California Los Angeles, California, 90089 (United States); Scott, A. [UCSB Department of Physics, Santa Barbara, California, 93106 (United States); Yoder, R. [Manhattan College, Riverdale, New York, 10471 (United States)

2006-11-27T23:59:59.000Z

62

Ultra-high-mass mass spectrometry with charge discrimination using cryogenic detectors  

DOE Patents [OSTI]

An ultra-high-mass time-of-flight mass spectrometer using a cryogenic particle detector as an ion detector with charge discriminating capabilities. Cryogenic detectors have the potential for significantly improving the performance and sensitivity of time-of-flight mass spectrometers, and compared to ion multipliers they exhibit superior sensitivity for high-mass, slow-moving macromolecular ions and can be used as "stop" detectors in time-of-flight applications. In addition, their energy resolving capability can be used to measure the charge state of the ions. Charge discrimination is very valuable in all time-of-flight mass spectrometers. Using a cryogenically-cooled Nb-Al.sub.2 O.sub.3 -Nb superconductor-insulator-superconductor (SIS) tunnel junction (STJ) detector operating at 1.3 K as an ion detector in a time-of-flight mass spectrometer for large biomolecules it was found that the STJ detector has charge discrimination capabilities. Since the cryogenic STJ detector responds to ion energy and does not rely on secondary electron production, as in the conventionally used microchannel plate (MCP) detectors, the cryogenic detector therefore detects large molecular ions with a velocity-independent efficiency approaching 100%.

Frank, Matthias (Berkeley, CA); Mears, Carl A. (Oakland, CA); Labov, Simon E. (Berkeley, CA); Benner, W. Henry (Danville, CA)

1999-01-01T23:59:59.000Z

63

Friction and wear behavior of ultra-high molecular weight polyethylene as a function of polymer crystallinity  

E-Print Network [OSTI]

Friction and wear behavior of ultra-high molecular weight polyethylene as a function of polymer-grade ultra-high molecular weight polyethylene (UHMWPE) (GUR 1050 resin) were evaluated as a function replacements; Ultra-high molecular weight polyethylene (UHMWPE); Crystallinity; Friction; Wear 1. Introduction

Lin, Zhiqun

64

Improved performance of ultra-high molecular weight polyethylene for orthopedic applications  

E-Print Network [OSTI]

A considerable number of total-joint replacement devices used in orthopedic medicine involve articulation between a metallic alloy and ultra-high molecular weight polyethylene (UHMWPE). Though this polymer has excellent wear resistance, the wear...

Plumlee, Kevin Grant

2009-05-15T23:59:59.000Z

65

Methods for increasing the thermal conductivity of ultra-high molecular weight polyethylene (UHMWPE)  

E-Print Network [OSTI]

A two-part study was conducted to determine methods for producing ultra-high molecular weight polyethylene with high thermal conductivity by way of polymer chain orientation. The first portion of this report surveys current ...

Miler, Josef L

2006-01-01T23:59:59.000Z

66

Press and Dryer Roll Surgaces and Web Transfer Systems for Ultra High Paper Maching Speeds  

SciTech Connect (OSTI)

The objective of the project was to provide fundamental knowledge and diagnostic tools needed to design new technologies that will allow ultra high speed web transfer from press rolls and dryer cylinders.

T. F. Patterson

2004-03-15T23:59:59.000Z

67

Bimodal solar system based on a ultra-high-temperature TEC  

SciTech Connect (OSTI)

The paper considers an ecological, solar, bimodal system with ultra-high temperature thermionic energy converter (TEC). The solar bimodal Space Electric Propulsion System (SEPS) characteristics are presented. {copyright} {ital 1996 American Institute of Physics.}

Ogloblin, B.G.; Kirillov, E.Y.; Klimov, A.V.; Shalaev, A.I.; Shumov, D.P. [Central Design Bureau of Machine Building, Krasnogvardeyskaya Square 3, St. Petersburg, (Russia) 195272; Ender, A.Y.; Kuznetsov, V.I.; Sitnov, V.I. [Ioffe Physico-Technical Institute, Politekhnicheskaya St. 26, St. Petersburg, (Russia) 194021

1996-03-01T23:59:59.000Z

68

New Ultra-High Speed Network Connection for Researchers and Educators is 10  

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

Ultra-High Speed Network Connection for Researchers and Ultra-High Speed Network Connection for Researchers and Educators is 10 Times Faster Than Commercial Internet Providers New Ultra-High Speed Network Connection for Researchers and Educators is 10 Times Faster Than Commercial Internet Providers October 13, 2011 - 10:47am Addthis Washington, D.C. - U.S. Energy Secretary Steven Chu today announced the activation of an ultra-high speed network connection for scientists, researchers and educators at universities and National Laboratories that is at least ten times faster than commercial Internet providers. The project - funded with $62 million from the 2009 economic stimulus law - is intended for research use but could pave the way for widespread commercial use of similar technology. "While this breakthrough will make sharing information between our labs

69

A limit on the ultra-high-energy neutrino flux from lunar observations with the Parkes radio telescope  

E-Print Network [OSTI]

We report a limit on the ultra-high-energy neutrino flux based on a non-detection of radio pulses from neutrino-initiated particle cascades in the Moon, in observations with the Parkes radio telescope undertaken as part of the LUNASKA project. Due to the improved sensitivity of these observations, which had an effective duration of 127 hours and a frequency range of 1.2-1.5 GHz, this limit extends to lower neutrino energies than those from previous lunar radio experiments, with a detection threshold below 10^20 eV. The calculation of our limit allows for the possibility of lunar-origin pulses being misidentified as local radio interference, and includes the effect of small-scale lunar surface roughness. The targeting strategy of the observations also allows us to place a directional limit on the neutrino flux from the nearby radio galaxy Centaurus A.

Bray, J D; Roberts, P; Reynolds, J E; James, C W; Phillips, C J; Protheroe, R J; McFadden, R A; Aartsen, M G

2015-01-01T23:59:59.000Z

70

HIGH-ENERGY EMISSION INDUCED BY ULTRA-HIGH-ENERGY PHOTONS AS A PROBE OF ULTRA-HIGH-ENERGY COSMIC-RAY ACCELERATORS EMBEDDED IN THE COSMIC WEB  

SciTech Connect (OSTI)

The photomeson production in ultra-high-energy cosmic-ray (UHECR) accelerators such as {gamma}-ray bursts and active galaxies may lead to ultra-high-energy (UHE) {gamma}-ray emission. We show that the generation of UHE pairs in magnetized structured regions where the sources are embedded is inevitable, and accompanying {approx}> 0.1 TeV synchrotron emission provides an important probe of UHECR acceleration. It would especially be relevant for powerful transient sources, and synchrotron pair echoes may be detected by future CTA via coordinated search for transients of duration {approx}0.1-1 yr for the structured regions of {approx}Mpc. Detections will be useful for knowing structured extragalactic magnetic fields as well as properties of the sources.

Murase, Kohta [Department of Physics, Center for Cosmology and AstroParticle Physics, Ohio State University, Columbus, OH 43210 (United States)

2012-02-15T23:59:59.000Z

71

Sintering and properties of Ultra High Temperature Ceramics for aerospace applications J.F. Justin  

E-Print Network [OSTI]

thermal shock resistance and makes them ideal for many high-temperature thermal applications : France (2013)" #12;for example, a high thermal conductivity reduces thermal stress within the material-francois.justin@onera.fr ABSTRACT The Ultra High Temperature Ceramics (UHTCs) represent a very interesting family of materials

72

Time Variation of Ultra High Energy -Ray from SN1987A  

Science Journals Connector (OSTI)

......as well as UHE neutrinos with energy up to 1016 eV. Luminosity of...the supernova explosion with energy 1.4 1017 ergs/g is 7 Mo...to 7 1041 ergs/s at most if muons generated by the UHE neutrons...2 (1988) pp. 416-428 Energy Spectrum of Ultra High Energy......

Takashi Nakamura; Yoshiyuki Yamada; Humitaka Sato

1987-11-01T23:59:59.000Z

73

Computational performance of ultra-high-resolution capability in the Community Earth System Model  

Science Journals Connector (OSTI)

With the fourth release of the Community Climate System Model, the ability to perform ultra-high-resolution climate simulations is now possible, enabling eddy-resolving ocean and sea-ice models to be coupled to a finite-volume atmosphere model for a ... Keywords: Earth system modeling, Performance engineering, application optimization, climate modeling, high-resolution

John M. Dennis; Mariana Vertenstein; Patrick H. Worley; Arthur A. Mirin; Anthony P. Craig; Robert Jacob; Sheri Mickelson

2012-02-01T23:59:59.000Z

74

Prediction of Ultra-High Aspect Ratio Nanowires from Self-Assembly  

E-Print Network [OSTI]

Prediction of Ultra-High Aspect Ratio Nanowires from Self-Assembly Zhigang Wu and Jeffrey C to investigate the possible self-assembly of nanoscale objects into ultrahigh aspect ratio chains and wires. Self-assembly17,18 from nanosize building blocks is regarded as one of the most promising methods

Wu, Zhigang

75

KolmogorovSmirnov test as a tool to study the distribution of ultra-high energy cosmic ray sources  

Science Journals Connector (OSTI)

......distribution of ultra-high energy cosmic ray sources D. Harari...Bustillo 9500, Bariloche, 8400 Argentina We analyse in detail the two-dimensional...sources of the ultra-high energy cosmic rays. We confront...rays (CRs) is the enormous energies they can reach, which can......

D. Harari; S. Mollerach; E. Roulet

2009-04-01T23:59:59.000Z

76

A Combined Electrochemical and Ultra-High Vacuum Approach to Heterogeneous  

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

A Combined Electrochemical and Ultra-High Vacuum Approach to Heterogeneous A Combined Electrochemical and Ultra-High Vacuum Approach to Heterogeneous Electrocatalysis Friday, February 24, 2012 - 11:00am SSRL Bldg. 137-322, 3rd floor Conference Room Matthew A. Rigsby, Oak Ridge National Laboratory Improved energy conversion and storage technologies are crucial for meeting the growing energy demands of the world. Understanding the factors that are currently limiting the advancement of these technologies is vital. One must examine the fundamental properties of electrocatalyst/photoelectrocatalyst materials and the fluid-solid interfaces of which they are a part, and one of the simplest ways to do this is to study model electrocatalyst systems. In the work presented here, studies began with real nanoparticle fuel cell electrocatalysts that demonstrated the key relationship between reactivity

77

ARM - Instrument - uhsas  

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

The ultra-high sensitivity aerosol spectrometer (UHSAS) uses a relatively high-powered near infrared laser to illuminate the aerosol sample volume and collects and measures the...

78

Direct Aerosol Forcing Uncertainty  

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

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

Mccomiskey, Allison

79

Tidal disruption jets as the source of Ultra-High Energy Cosmic Rays  

E-Print Network [OSTI]

Observations of the spectacular, blazar-like tidal disruption event (TDE) candidates Swift J1644+57 and J2058+05 show that the conditions required for accelerating protons to 10^{20} eV appear to be realized in the outer jet, and possibly in the inner jet as well. Direct and indirect estimates of the rate of jetted-TDEs, and of the energy they inject, are compatible with the observed flux of ultra-high energy cosmic rays (UHECRs) and the abundance of presently contributing sources. Thus TDE-jets can be a major source of UHECRs, even compabile with a pure proton composition.

Farrar, Glennys R

2014-01-01T23:59:59.000Z

80

Simulation of Ultra High Energy Neutrino Interactions in Ice and Water  

E-Print Network [OSTI]

The CORSIKA program, usually used to simulate extensive cosmic ray air showers, has been adapted to work in a water or ice medium. The adapted CORSIKA code was used to simulate hadronic showers produced by neutrino interactions. The simulated showers have been used to study the spatial distribution of the deposited energy in the showers. This allows a more precise determination of the acoustic signals produced by ultra high energy neutrinos than has been possible previously. The properties of the acoustic signals generated by such showers are described.

S. Bevan; S. Danaher; J. Perkin; S. Ralph; C. Rhodes; L. Thompson; T. Sloan; D. Waters

2007-04-08T23:59:59.000Z

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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

Simulation of Ultra High Energy Neutrino Interactions in Ice and Water  

E-Print Network [OSTI]

The CORSIKA program, usually used to simulate extensive cosmic ray air showers, has been adapted to work in a water or ice medium. The adapted CORSIKA code was used to simulate hadronic showers produced by neutrino interactions. The simulated showers have been used to study the spatial distribution of the deposited energy in the showers. This allows a more precise determination of the acoustic signals produced by ultra high energy neutrinos than has been possible previously. The properties of the acoustic signals generated by such showers are described.

Bevan, S; Perkin, J; Ralph, S; Rhodes, C; Thompson, L; Sloan, T; Waters, D

2007-01-01T23:59:59.000Z

82

A focusable, convergent fast-electron beam from ultra-high-intensity laser-solid interactions  

E-Print Network [OSTI]

A novel scheme for the creation of a convergent, or focussing, fast-electron beam generated from ultra-high-intensity laser-solid interactions is described. Self-consistent particle-in-cell simulations are used to demonstrate the efficacy of this scheme in two dimensions. It is shown that a beam of fast-electrons of energy 500 keV - 3 MeV propagates within a solid-density plasma, focussing at depth. The depth of focus of the fast-electron beam is controlled via the target dimensions and focussing optics.

Scott, R H H

2015-01-01T23:59:59.000Z

83

Low loss hollow optical-waveguide connection from atmospheric pressure to ultra-high vacuum  

SciTech Connect (OSTI)

A technique for optically accessing ultra-high vacuum environments, via a photonic-crystal fiber with a long small hollow core, is described. The small core and the long bore enable a pressure ratio of over 10{sup 8} to be maintained between two environments, while permitting efficient and unimpeded delivery of light, including ultrashort optical pulses. This delivery can be either passive or can encompass nonlinear optical processes such as optical pulse compression, deep UV generation, supercontinuum generation, or other useful phenomena.

Ermolov, A.; Mak, K. F.; Tani, F.; Hlzer, P.; Travers, J. C. [Max Planck Institute for the Science of Light, Gnther-Scharowsky-Str. 1, 91058 Erlangen (Germany)] [Max Planck Institute for the Science of Light, Gnther-Scharowsky-Str. 1, 91058 Erlangen (Germany); Russell, P. St. J. [Max Planck Institute for the Science of Light, Gnther-Scharowsky-Str. 1, 91058 Erlangen (Germany) [Max Planck Institute for the Science of Light, Gnther-Scharowsky-Str. 1, 91058 Erlangen (Germany); Department of Physics, University of Erlangen-Nuremberg, Gnther-Scharowsky-Str. 1, 91058 Erlangen (Germany)

2013-12-23T23:59:59.000Z

84

aerosols | EMSL  

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

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

85

Fast Neutron - Mirror Neutron Oscillation and Ultra High Energy Cosmic Rays  

E-Print Network [OSTI]

If there exists the mirror world, a parallel hidden sector of particles with exactly the same microphysics as that of the observable particles, then the primordial nucleosynthesis constraints require that the temperature of the cosmic background of mirror relic photons should be smaller than that of the ordinary relic photons, T'/T neutron - mirror neutron oscillation in vacuum, with an oscillation time $\\tau \\sim 1$ s, much smaller than the neutron lifetime. We show that this could provide a very efficient mechanism for transporting ultra high energy protons at large cosmological distances. The mechanism operates as follows: a super-GZK energy proton scatters a relic photon producing a neutron that oscillates into a mirror neutron which then decays into a mirror proton. The latter undergoes a symmetric process, scattering a mirror relic photon and producing back an ordinary nucleon, but only after traveling a distance $(T/T')^{3}$ times larger than ordinary protons. This may relax or completely remove the GZK-cutoff in the cosmic ray spectrum and also explain the correlation between the observed ultra high energy protons and far distant sources as are the BL Lacs.

Zurab Berezhiani; Luis Bento

2006-02-24T23:59:59.000Z

86

Development of an Ultra High Frequency Gyrotron with a Pulsed Magnet  

SciTech Connect (OSTI)

An ultra-high frequency gyrotron is being developed as a THz radiation source by using a pulsed magnet. We have achieved the highest field intensity of 20.2 T. High frequency operation at the second harmonic will achieve 1.01 THz; the corresponding cavity mode is TE6,11,1. On the other hand, an ultra-high power gyrotron with a pulsed magnet is also being developed as a millimeter to submillimeter wave radiation source. The gyrotron is a large orbit gyrotron (LOG) using an intense relativistic electron beam (IREB). A pulsed power generator 'ETIGO-IV' is applied for generation of the IREB. A prototype relativistic LOG was constructed for fundamental operation. The output of the LOG will achieve 144 GHz and 9 MW; the corresponding cavity mode is TE1,4,1. Cavities for 2nd and 4th harmonic operations were designed by numerical simulation for achievement of higher frequency. The progress of development for prototype high frequency gyrotrons with pulsed magnets is presented.

Idehara, T.; Kamada, M.; Tsuchiya, H.; Hayashi, T.; Agusu, La; Mitsudo, S.; Ogawa, I. [Research Center for Development of Far Infrared Region, University of Fukui, Bunkyo 3-9-1, Fukui-shi 910-8507 (Japan); Manuilov, V. N. [Research Center for Development of Far Infrared Region, University of Fukui, Bunkyo 3-9-1, Fukui-shi 910-8507 (Japan); Radiophysical Department of Nizhny Novgorod State University, 690005, Gagarin av., 23, Nizhny Novgorod (Russian Federation); Naito, K.; Yuyama, T.; Jiang, W.; Yatsui, K. [Extreme Energy-Density Research Institute, Nagaoka University of Technology, Kamitomioka 1603-1, Nagaoka-shi, Niigata 940-2188 (Japan)

2006-01-03T23:59:59.000Z

87

Ultra High Energy Cosmic Rays and Gamma Ray Bursts from Axion Stars  

E-Print Network [OSTI]

We propose a model in which ultra high energy cosmic rays and gamma ray bursts are produced by collisions between neutron stars and axion stars. The acceleration of such a cosmic ray is made by the electric field, $\\sim 10^{15} (B/10^{12} {G}) {eV} {cm}^{-1}$, which is induced in an axion star by relatively strong magnetic field $B>10^{12}$ G of a neutron star. On the other hand, similar collisions generate gamma ray bursts when magnetic field is relatively small, e.g. $\\leq 10^{10}$ G. Assuming that the axion mass is $\\sim 10^{-9}$ eV, we can explain huge energies of the gamma ray bursts $\\sim 10^{54}$ erg as well as the ultra high energies of the cosmic rays $\\sim 10^{20}$ eV. We estimate rate of energy release in the collisions and we find that the rate roughly agrees with observations. In addition, we show that these axion stars are plausible candidates for MACHOs. Since the axion star induces oscillating electric current under the magnetic field, observable monochromatic radiations are emitted.

Aiichi Iwazaki

2000-08-29T23:59:59.000Z

88

Detection of internally mixed Asian dust with air pollution aerosols using a polarization optical particle counter and a polarization-sensitive two-wavelength lidar  

Science Journals Connector (OSTI)

Abstract East Asia is a unique region where mineral dust (Asian dust) sources are located near urban and industrial areas. Asian dust is often mixed with air pollution aerosols during transportation. It is important to understand the mixing states of Asian dust and other aerosols, because the effects on the environment and human health differ depending on the mixing state. We studied the mixing states of Asian dust using a polarization particle counter (POPC) that measures the forward scattering and the two polarization components of backscattering for single particles and a polarization-sensitive (532nm) two-wavelength (1064nm and 532nm) lidar. We conducted the simultaneous observations using the POPC and the lidar in Seoul from March to December 2013 and captured the characteristics of pure Asian dust and internally mixed polluted Asian dust. POPC measurements indicated that the density of large particles was lower in polluted Asian dust that transported slowly over the polluted areas than in pure Asian dust that transported quickly from the dust source region. Moreover, the backscattering depolarization ratio was smaller for all particle sizes in polluted dust. The optical characteristics measured using the lidar were consistent with the POPC measurements. The backscattering color ratio of polluted dust was comparable to that of pure dust, but the depolarization ratio was lower for polluted dust. In addition, coarse non-spherical particles (Asian dust) almost always existed in the background, and the depolarization ratio had seasonal variation with a lower depolarization ratio in the summer. These results suggest background Asian dust particles are internally mixed in the summer.

Nobuo Sugimoto; Tomoaki Nishizawa; Atsushi Shimizu; Ichiro Matsui; Hiroshi Kobayashi

2015-01-01T23:59:59.000Z

89

Constraining the fraction of primary gamma rays at ultra-high energies from the muon data of the Yakutsk extensive-air-shower array  

E-Print Network [OSTI]

By making use of the data on the total signal and on the muon component of the air showers detected by the Yakutsk array, we analyze, in the frameworks of the recently suggested event-by-event approach, how large the fraction of primary gamma-rays at ultra-high energies can be. We derive upper limits on the photon fraction in the integral flux of primary cosmic rays. At the 95% confidence level (CL), these limits are 22% for primary energies E_0>4\\cdot 10^{19}eV and 12% for E_0>2\\cdot 10^{19}eV. Despite the presence of muonless events, the data are consistent with complete absence of photons at least at 95% CL. The sensitivity of the results to systematic uncertainties, in particular to those of the energy determination for non-photon primaries, is discussed.

A. V. Glushkov; D. S. Gorbunov; I. T. Makarov; M. I. Pravdin; G. I. Rubtsov; I. E. Sleptsov; S. V. Troitsky

2007-01-09T23:59:59.000Z

90

Analog Readout and Analysis Software for the Ultra-High Rate Germanium (UHRGe) Project  

SciTech Connect (OSTI)

High-resolution high-purity germanium (HPGe) spectrometers are needed for Safeguards applications such as spent fuel assay and uranium hexafluoride cylinder verification. In addition, these spectrometers would be applicable to other high-rate applications such as non-destructive assay of nuclear materials using nuclear resonance fluorescence. Count-rate limitations of today's HPGe technologies, however, lead to concessions in their use and reduction in their efficacy. Large-volume, very high-rate HPGe spectrometers are needed to enable a new generation of nondestructive assay systems. The Ultra-High Rate Germanium (UHRGe) project is developing HPGe spectrometer systems capable of operating at unprecedented rates, 10 to 100 times those available today. This report documents current status of developments in the analog electronics and analysis software.

Fast, James E.; Aguayo Navarrete, Estanislao; Evans, Allan T.; VanDevender, Brent A.; Rodriguez, Douglas C.; Wood, Lynn S.

2011-09-01T23:59:59.000Z

91

Implications of the pseudo-Dirac scenario for ultra high energy neutrinos from GRBs  

SciTech Connect (OSTI)

The source of Ultra High Energy Cosmic Rays (UHECR) is still an unresolved mystery. Up until recently, sources of Gamma Ray Bursts (GRBs) had been considered as a suitable source for UHECR. Within the fireball model, the UHECR produced at GRBs should be accompanied with a neutrino flux detectable at the neutrino telescope such as IceCube. Recently, IceCube has set an upper bound on the neutrino flux accompanied by GRBs about 3.7 times below the prediction. We investigate whether this deficit can be explained by the oscillation of the active neutrinos to sterile neutrinos en route from the source to the detectors within the pseudo-Dirac scenario. We then discuss the implication of this scenario for diffuse supernova relic neutrinos.

Esmaili, Arman [Instituto de Fisica Gleb Wataghin UNICAMP, 13083-859, Campinas, SP (Brazil); Farzan, Yasaman, E-mail: aesmaili@ifi.unicamp.br, E-mail: yasaman@theory.ipm.ac.ir [School of Physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of)

2012-12-01T23:59:59.000Z

92

Gas and RRR distribution in high purity Niobium EB welded in Ultra-High Vacuum  

SciTech Connect (OSTI)

Electron beam (EB) welding in UHV (ultra-high vacuum, 10-5 divide 10-8 mbar) is applied in the standard fabrication of high gradient niobium superconducting radio frequency (SRF) cavities of TESLA design. The quality of EB welding is critical for cavity performance. Experimental data of gas content (H2, O2, N2) and RRR (residual resistivity ratio) measurements in niobium (Nb) welding seams are presented. EB welding in UHV conditions allow to preserve low gas content (1 divide 3 wt. ppm hydrogen and 5 divide 7 ppm oxygen and nitrogen), essential for high values of RRR - 350 divide 400 units. Gas content redistribution in the electron beam welded and heat affected region take place in the welding process. Correlation between gas solubility parameters, RRR and thermal conductivity are presented. Mechanisms of gas solubility in EB welding process are discussed.

Anakhov, S.; Singer, X.; Singer, W.; Wen, H. [RSVPU, Yekaterinburg (Russian Federation); DESY, Hamburg (Germany); IEE CAS, Beijing (China)

2006-05-24T23:59:59.000Z

93

Copper coated carbon fiber reinforced plastics for high and ultra high vacuum applications  

E-Print Network [OSTI]

We have used copper-coated carbon fiber reinforced plastic (CuCFRP) for the construction of high and ultra-high vacuum recipients. The vacuum performance is found to be comparable to typical stainless steel used for this purpose. In test recipients we have reached pressures of 2E-8 mbar and measured a desorption rate of 1E-11 mbar*liter/s/cm^2; no degradation over time (2 years) has been found. Suitability for baking has been found to depend on the CFRP production process, presumably on the temperature of the autoclave curing. Together with other unique properties of CuCFRP such as low weight and being nearly non-magnetic, this makes it an ideal material for many high-end vacuum applications.

Burri, F; Feusi, P; Henneck, R; Kirch, K; Lauss, B; Ruettimann, P; Schmidt-Wellenburg, P; Schnabel, A; Voigt, J; Zenner, J; Zsigmond, G

2013-01-01T23:59:59.000Z

94

Gamma-Ray Bursts, Ultra High Energy Cosmic Rays, and Cosmic Gamma-Ray Background  

E-Print Network [OSTI]

We argue that gamma-ray bursts (GRBs) may be the origin of the cosmic gamma-ray background radiation observed in GeV range. It has theoretically been discussed that protons may carry a much larger amount of energy than electrons in GRBs, and this large energy can be radiated in TeV range by synchrotron radiation of ultra-high-energy protons (\\sim 10^{20} eV). The possible detection of GRBs above 10 TeV suggested by the Tibet and HEGRA groups also supports this idea. If this is the case, most of TeV gamma-rays from GRBs are absorbed in intergalactic fields and eventually form GeV gamma-ray background, whose flux is in good agreement with the recent observation.

Tomonori Totani

1998-10-14T23:59:59.000Z

95

Telescope Array Radar (TARA) observatory for Ultra-High Energy Cosmic Rays  

Science Journals Connector (OSTI)

Abstract Construction was completed during summer 2013 on the Telescope Array \\{RAdar\\} (TARA) bi-static radar observatory for Ultra-High Energy Cosmic Rays (UHECR). TARA is co-located with the Telescope Array, the largest conventional cosmic ray detector in the Northern Hemisphere, in radio-quiet Western Utah. TARA employs an 8MW Effective Radiated Power (ERP) VHF transmitter and smart receiver system based on a 250MS/s data acquisition system in an effort to detect the scatter of sounding radiation by UHECR-induced atmospheric ionization. TARA seeks to demonstrate bi-static radar as a useful new remote sensing technique for UHECRs. In this report, we describe the design and performance of the TARA transmitter and receiver systems.

R. Abbasi; M. Abou Bakr Othman; C. Allen; L. Beard; J. Belz; D. Besson; M. Byrne; B. Farhang-Boroujeny; A. Gardner; W.H. Gillman; W. Hanlon; J. Hanson; C. Jayanthmurthy; S. Kunwar; S.L. Larson; I. Myers; S. Prohira; K. Ratzlaff; P. Sokolsky; H. Takai; G.B. Thomson; D. Von Maluski

2014-01-01T23:59:59.000Z

96

An Efficient, Movable Single-Particle Detector for Use in Cryogenic Ultra-High Vacuum Environments  

E-Print Network [OSTI]

A compact, highly efficient single-particle counting detector for ions of keV/u kinetic energy, movable by a long-stroke mechanical translation stage, has been developed at the Max-Planck-Institut f\\"ur Kernphysik (Max Planck Institute for Nuclear Physics, MPIK). Both, detector and translation mechanics, can operate at ambient temperatures down to $\\sim$ 10 K and consist fully of ultra-high vacuum (UHV) compatible, high-temperature bakeable and non-magnetic materials. The set-up is designed to meet the technical demands of MPIK's Cryogenic Storage Ring (CSR). We present a series of functional tests that demonstrate full suitability for this application and characterise the set-up with regard to its particle detection efficiency.

Spruck, Kaija; Fellenberger, Florian; Grieser, Manfred; von Hahn, Robert; Klinkhamer, Vincent; Novotn, Old?ich; Schippers, Stefan; Vogel, Stephen; Wolf, Andreas; Krantz, Claude

2014-01-01T23:59:59.000Z

97

Ultra-high-resolution alpha spectrometry for nuclear forensics and safeguards applications  

SciTech Connect (OSTI)

We will present our work on the development of ultra-high-resolution detectors for alpha particle spectrometry. These detectors, based on superconducting transition-edge sensors, offer energy resolution that is five to ten times better than conventional silicon detectors. Using these microcalorimeter detectors, the isotopic composition of mixed-actinide samples can be determined rapidly without the need for actinide separation chemistry to isolate each element, or mass spectrometry to separate isotopic signatures that can not be resolved using traditional alpha spectrometry (e.g. Pu-239/Pu-240, or Pu-238/Am-241). This paper will cover the detector and measurement system, actinide source preparation, and the quantitative isotopic analysis of a number of forensics- and safeguards-relevant radioactive sources.

Bacrania, Minesh K [Los Alamos National Laboratory; Croce, Mark [Los Alamos National Laboratory; Bond, Evelyn [Los Alamos National Laboratory; Dry, Donald [Los Alamos National Laboratory; Moody, W. Allen [Los Alamos National Laboratory; Lamont, Stephen [Los Alamos National Laboratory; Rabin, Michael [Los Alamos National Laboratory; Rim, Jung [Los Alamos National Laboratory; Smith, Audrey [Los Alamos National Laboratory; Beall, James [NIST-BOULDER; Bennett, Douglas [NIST-BOULDER; Kotsubo, Vincent [NIST-BOULDER; Horansky, Robert [NIST-BOULDER; Hilton, Gene [NIST-BOULDER; Schmidt, Daniel [NIST-BOULDER; Ullom, Joel [NIST-BOULDER; Cantor, Robin [STAR CRYOELECTRONICS

2010-01-01T23:59:59.000Z

98

Resistance minimum observed at Landau level filling factor ?=1/2 in ultra high magnetic fields  

Science Journals Connector (OSTI)

We study the magnetotransport near Landau level filling factor ?=1/2 in a gated GaAs-Al0.3Ga0.7As square quantum well (width 35 nm) in magnetic field up to 45 T and in a temperature (T) range between 50 mK and 1.5 K. The longitudinal resistance at ?=1/2, Rxx(?=1/2), exhibits a steep valley that is flanked by a pair of rising resistance peaks in low T. The Rxx(?=1/2) shows nonmonotonous dependence on T, with a minimum resistance reached at T?0.5?K. The concomitant Hall resistance Rxy is not strictly linear with magnetic field and its slope shows a sharp cusp at ?=1/2, indicating a nonclassical Hall effect. The data are characteristic for ultra high field magnetotransport around ?=1/2 in thick, but single-layer, quantum wells.

Jian Zhang; R. R. Du; J. A. Simmons; J. L. Reno

2010-01-21T23:59:59.000Z

99

Magnetars in the Metagalaxy: An Origin for Ultra High Energy Cosmic Rays in the Nearby Universe  

E-Print Network [OSTI]

I show that the relativistic winds of newly born magnetars with khz initial spin rates, occurring in all normal galaxies, can accelerate ultrarelativistic light ions with an E^{-1} injection spectrum, steepening to E^{-2} at higher energies, with an upper cutoff above 10^{21} eV. Interactions with the CMB yield a spectrum in good accord with the observed spectrum of Ultra-High Energy Cosmic Rays (UHECR), if ~ 5-10% of the magnetars are born with voltages sufficiently high to accelerate the UHECR. The form the spectrum spectrum takes depends on the gravitational wave losses during the magnetars' early spindown - pure electromagnetic spindown yields a flattening of the E^3 J(E) spectrum below 10^{20} eV, while a moderate GZK ``cutoff'' appears if gravitational wave losses are strong enough. I outline the physics such that the high energy particles escape with small energy losses from a magnetar's natal supernova, including Rayleigh-Taylor ``shredding'' of the supernova envelope, expansion of a relativistic blast wave into the interstellar medium, acceleration of the UHE ions through surf-riding in the electromgnetic fields of the wind, and escape of the UHE ions in the rotational equator with negligible radiation loss. The abundance of interstellar supershells and unusually large supernova remnants suggests that most of the initial spindown energy is radiated in khz gravitational waves for several hours after each supernova, with effective strains from sources at typical distances ~ 3 x 10^{-21}. Such bursts of gravitational radiation should correlate with bursts of ultra-high energy particles. The Auger experiment should see such bursts every few years.

Jonathan Arons

2002-08-23T23:59:59.000Z

100

Ultra-High Energy Cosmic Rays from Centaurus A: Jet Interaction with Gaseous Shells  

E-Print Network [OSTI]

Ultra high energy cosmic rays (UHECRs), with energies above ~6 x 10^19 eV, seem to show a weak correlation with the distribution of matter relatively near to us in the universe. It has earlier been proposed that UHECRs could be accelerated in either the nucleus or the outer lobes of the nearby radio galaxy Cen A. We show that UHECR production at a spatially intermediate location about 15 kpc northeast from the nucleus, where the jet emerging from the nucleus is observed to strike a large star-forming shell of gas, is a plausible alternative. A relativistic jet is capable of accelerating lower-energy heavy seed cosmic rays (CRs) to UHECRs on timescales comparable to the time it takes the jet to pierce the large gaseous cloud. In this model many CRs arising from a starburst, with a composition enhanced in heavy elements near the knee region around PeV, are boosted to ultra-high energies by the relativistic shock of a newly oriented jet. This model matches the overall spectrum shown by the Auger data and also makes a prediction for the chemical composition as a function of particle energy. We thus predict an observable anisotropy in the composition at high energy in the sense that lighter nuclei should preferentially be seen toward the general direction of Cen A. Taking into consideration the magnetic field models for the Galactic disk and a Galactic magnetic wind, this scenario may resolve the discrepancy between HiRes and Auger results concerning the chemical composition of UHECRs.

Gopal-Krishna; Peter L. Biermann; Vitor de Souza; Paul J. Wiita

2010-06-25T23:59:59.000Z

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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101

WO3 and HPA based system for ultra high activity and stability ofInnovation for Our Energy Future  

E-Print Network [OSTI]

Future ultra-high activity and stability of Pt catalysts in PEMFC cathodes 2010 DOE Hydrogen Program Fuel modification to approach automotive PEMFC activity (4x increase) and durability target (5000h/10y). ·· Lower-support interaction ­ lower loss in ECA ­ enhance catalyst activity · Lower costs ­ simplify & lower system cost

102

Modeling and compensation of cutting-forces generated during the EDM process for ultra high-precision robots  

E-Print Network [OSTI]

Modeling and compensation of cutting-forces generated during the EDM process for ultra high to compen- sate them during the robot usage. We have taken the micro electro-discharge machining process kinematic). Figure 2 Kinematic chain of the robot. The micro-EDM process is used for cutting complex shapes

Floreano, Dario

103

A Sensitivity Study of Radiative Fluxes at the Top of Atmosphere to Cloud-Microphysics and Aerosol Parameters in the Community Atmosphere Model CAM5  

SciTech Connect (OSTI)

In this study, we investigated the sensitivity of net radiative fluxes (FNET) at the top of atmosphere (TOA) to 16 selected uncertain parameters mainly related to the cloud microphysics and aerosol schemes in the Community Atmosphere Model version 5 (CAM5). We adopted a quasi-Monte Carlo (QMC) sampling approach to effectively explore the high dimensional parameter space. The output response variables (e.g., FNET) were simulated using CAM5 for each parameter set, and then evaluated using generalized linear model analysis. In response to the perturbations of these 16 parameters, the CAM5-simulated global annual mean FNET ranges from -9.8 to 3.5 W m-2 compared to the CAM5-simulated FNET of 1.9 W m-2 with the default parameter values. Variance-based sensitivity analysis was conducted to show the relative contributions of individual parameter perturbation to the global FNET variance. The results indicate that the changes in the global mean FNET are dominated by those of cloud forcing (CF) within the parameter ranges being investigated. The size threshold parameter related to auto-conversion of cloud ice to snow is confirmed as one of the most influential parameters for FNET in the CAM5 simulation. The strong heterogeneous geographic distribution of FNET variation shows parameters have a clear localized effect over regions where they are acting. However, some parameters also have non-local impacts on FNET variance. Although external factors, such as perturbations of anthropogenic and natural emissions, largely affect FNET variations at the regional scale, their impact is weaker than that of model internal parameters in terms of simulating global mean FNET in this study. The interactions among the 16 selected parameters contribute a relatively small portion of the total FNET variations over most regions of the globe. This study helps us better understand the CAM5 model behavior associated with parameter uncertainties, which will aid the next step of reducing model uncertainty via calibration of uncertain model parameters with the largest sensitivity.

Zhao, Chun; Liu, Xiaohong; Qian, Yun; Yoon, Jin-Ho; Hou, Zhangshuan; Lin, Guang; McFarlane, Sally A.; Wang, Hailong; Yang, Ben; Ma, Po-Lun; Yan, Huiping; Bao, Jie

2013-11-08T23:59:59.000Z

104

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

105

Discrete Alterations of Brain Network Structural Covariance in Individuals at Ultra-High Risk for Psychosis  

Science Journals Connector (OSTI)

AbstractBackground Investigation of aberrant large-scale brain networks offers novel insight into the role these networks play in diverse psychiatric disorders, such as schizophrenia. While there are studies reporting altered functional brain connectivity in participants at ultra-high risk (UHR) for psychosis, it is unclear whether these alterations extend to structural brain networks. Methods Whole-brain structural covariance patterns of 133 participants at UHR for psychosis (51 of whom subsequently developed psychosis) and 65 healthy controls (HC) were studied. Following data pre-processing (using VBM8), the mean signal in seed regions relating to specific networks (visual, auditory, motor, speech, semantic, executive, salience and default-mode) were extracted and voxel-wise analyses of covariance were conducted to compare the association between whole brain signal and each seed region for UHR and HC individuals. UHR participants who transitioned were compared to those who did not. Results Significantly reduced structural covariance was observed in the UHR sample compared to HC for the default-mode network, and increased covariance for the motor and executive control networks. When those who transitioned to psychosis were compared with those who did not, aberrant structural covariance was observed in the salience, executive-control, auditory and motor networks. Conclusions Whole-brain structural covariance analyses revealed subtle changes of connectivity of the default-mode, executive control, salience, motor and auditory networks in UHR individuals for psychosis. Although we found significant differences, these are small changes, and tend to reflect largely intact structural networks.

Kareen Heinze; Renate L.E.P. Reniers; Barnaby Nelson; Alison R. Yung; Ashleigh Lin; Ben J. Harrison; Christos Pantelis; Dennis Velakoulis; Patrick D. McGorry; Stephen J. Wood

2014-01-01T23:59:59.000Z

106

An (ultra) high-vacuum compatible sputter source for oxide thin film growth  

SciTech Connect (OSTI)

A miniaturised CF-38 mountable sputter source for oxide and metal thin film preparation with enhanced high-vacuum and ultra-high-vacuum compatibility is described. The all home-built sputtering deposition device allows a high flexibility also in oxidic sputter materials, suitable deposition rates for preparation of films in the nm- and the sub-monolayer regime and excellent reliability and enhanced cleanliness for usage in UHV chambers. For a number of technologically important yet hardly volatile materials, the described source represents a significant improvement over thermal deposition techniques like electron-beam- or thermal evaporation, as especially the latter are no adequate tool to prepare atomically clean layers of refractory oxide materials. Furthermore, it is superior to commercially available magnetron sputter devices, especially for applications, where highly reproducible sub-monolayer thin film preparation under very clean UHV conditions is required (e.g., for studying phase boundary effects in catalysis). The device in turn offers the usage of a wide selection of evaporation materials and special target preparation procedures also allow the usage of pressed oxide powder targets. To prove the performance of the sputter-source, test preparations with technologically relevant oxide components, comprising ZrO{sub 2} and yttrium-stabilized ZrO{sub 2}, have been carried out. A wide range of characterization methods (electron microscopy, X-ray photoelectron spectroscopy, low-energy ion scattering, atomic force microscopy, and catalytic testing) were applied to demonstrate the properties of the sputter-deposited thin film systems.

Mayr, Lukas; Kpfle, Norbert; Auer, Andrea; Kltzer, Bernhard; Penner, Simon [Institute for Physical Chemistry, University of Innsbruck, Innrain 52a, A-6020 Innsbruck (Austria)] [Institute for Physical Chemistry, University of Innsbruck, Innrain 52a, A-6020 Innsbruck (Austria)

2013-09-15T23:59:59.000Z

107

Are gamma-ray bursts the sources of ultra-high energy cosmic rays?  

E-Print Network [OSTI]

We reconsider the possibility that gamma-ray bursts (GRBs) are the sources of the ultra-high energy cosmic rays (UHECRs) within the internal shock model, assuming a pure proton composition of the UHECRs. For the first time, we combine the information from gamma-rays, cosmic rays, prompt neutrinos, and cosmogenic neutrinos quantitatively in a joint cosmic ray production and propagation model, and we show that the information on the cosmic energy budget can be obtained as a consequence. In addition to the neutron model, we consider alternative scenarios for the cosmic ray escape from the GRBs, i.e., that cosmic rays can leak from the sources. We find that the dip model, which describes the ankle in UHECR observations by the pair production dip, is strongly disfavored in combination with the internal shock model because a) unrealistically high baryonic loadings (energy in protons versus energy in electrons/gamma-rays) are needed for the individual GRBs and b) the prompt neutrino flux easily overshoots the corresponding neutrino bound. On the other hand, GRBs may account for the UHECRs in the ankle transition model if cosmic rays leak out from the source at the highest energies. In that case, we demonstrate that future neutrino observations can efficiently test most of the parameter space -- unless the baryonic loading is much larger than previously anticipated.

Philipp Baerwald; Mauricio Bustamante; Walter Winter

2014-07-07T23:59:59.000Z

108

Magnetized Sources of Ultra-high Energy Nuclei and Extragalactic Origin of the Ankle  

E-Print Network [OSTI]

It has recently been suggested that ultra-high energy cosmic rays could have an extragalactic origin down to the "second knee" at ~4x10^{17}eV. In this case the "ankle" or "dip" at ~5x10^{18}eV would be due to pair production of extragalactic protons on the cosmic microwave background which requires an injection spectrum of about E^{-2.6}. It has been pointed out that for injection of a mixed composition of nuclei a harder injection spectrum \\~E^{-2.2} is required to fit the spectra at the highest energies and a galactic component is required in this case to fit the spectrum below the ankle, unless the proton fraction is larger than 85%. Here we perform numerical simulations and find that for sufficiently magnetized sources, observed spectra above 10^{19}eV approach again the case of pure proton injection due to increased path-lengths and more efficient photo-disintegration of nuclei around the sources. This decreases secondary fluxes at a given energy and thus requires injection spectra ~E^{-2.6}, as steep as for pure proton injection. In addition, the ankle may again be sufficiently dominated by protons to be interpreted as a pair production dip.

Guenter Sigl; Eric Armengaud

2005-07-28T23:59:59.000Z

109

The isotropy problem of Sub-ankle Ultra-high energy cosmic rays  

E-Print Network [OSTI]

We study the time dependent propagation of sub-ankle ultra-high energy cosmic rays (UHECRs) originating from point-like Galactic sources. We show that drift in the Galactic magnetic field (GMF) may play an important role in the propagation of UHECRs and their measured anisotropy, particularly when the transport is anisotropic. To fully account for the discreteness of UHECR sources in space and time, a Monte Carlo method is used to randomly place sources in the Galaxy. The low anisotropy measured by Auger is not generally characteristic of the theoretical models, given that the sources are distributed in proportion to the star formation rate, but it can possibly be understood as a) intermittency effects due to the discrete nature of the sources or, with extreme parameters, b) a cancellation of drift current along a current sheet with the outward radial diffusive flux. We conclude that it is possible to interpret the Galactic sub-ankle CR flux as being due entirely to intermittent discrete Galactic sources dist...

Kumar, Rahul

2013-01-01T23:59:59.000Z

110

On the ultra high energy cosmic rays and the origin of the cosmic microwave background radiation  

E-Print Network [OSTI]

Some inconsistencies to the assumption of a cosmological origin of the cosmic microwave background CMB, such as the absence of gravitational lensing in the WMAP data, open the doors to some speculations such as a local origin to the CMB. We argue here that this assumption agrees with the absence of the GZK cutoff (at least according to AGASA data) in the energy spectrum of the cosmic ray due to the cosmic interaction with the CMB at $6\\times 10^{19} eV$ or above. Within 50 Mpc from Earth, the matter and light distributions are close to an anisotropic distribution, where the local cluster and local super-clusters of galaxies can be identified. In contrast, the ultra high energy comic rays data is consistent to an almost isotropic distribution, and there is no correlation between their arrival direction and astronomical sources within our local cluster. This means that the events above the GZK cutoff come from distances above 50 Mpc, without an apparent energy loss. This scenario is plausible under the assumption of the CMB concentrated only within 3-4 Mpc from Earth. In other words, the CMB has a local origin linked only to the local super-cluster of galaxies. In addition, the galactic and extragalactic energy spectra index within the energy equipartition theorem strongly constrains the dark matter and dark energy hypothesis, essential in the Big Bang cosmology.

C. E. Navia; C. R. A. Augusto; K. H. Tsui

2007-07-12T23:59:59.000Z

111

Optical analysis of an ultra-high resolution two-mirror soft x-ray microscope  

Science Journals Connector (OSTI)

Promoted by the successful application of multilayer coated optics in soft x-ray imaging experiments in solar physics and projection lithography, several groups have designed, analyzed, fabricated, and are testing Schwarzschild multilayer soft x-ray microscopes. Simulations have indicated that diffraction limited performance of a spherical Schwarzschild microscope operating near 100 will be limited to systems with a small numerical aperture of approximately 0.15 and a corresponding resolution, based on the Rayleigh criterion, of 3.3 times the wavelength of the incident radiation. In principle, a two aspherical mirror Head microscope, which satisfies the constant optical path length condition and the Abb sine condition, should achieve diffraction limited performance for very large numerical apertures. For a practical soft x-ray microscope, surface contour errors, microroughness, reflectance of multilayer coatings, and variation of the angle of incidence over the multilayer substrates become significant factors in degrading system resolution and must be controlled before an ultra-high resolution, two-mirror microscope will be realized. For a 30x reflecting microscope with a numerical aperture ranging from 0.15 to 0.35, the effects on resolution of surface contour errors, tilts, and misalignments of the optics have been studied. Graded spacing of the multilayer coatings on the mirror substrates are required of a fast, two-mirror microscope.

David L. Shealy; Cheng Wang; Richard B. Hoover

1995-01-01T23:59:59.000Z

112

Hadronic Multiparticle Production at Ultra-High Energies and Extensive Air Showers  

E-Print Network [OSTI]

Studies of the nature of cosmic ray particles at the highest energies are based on the measurement of extensive air showers. Most cosmic ray properties can therefore only be obtained from the interpretation of air shower data and are thus depending on predictions of hadronic interaction models at ultra-high energies. We discuss different scenarios of model extrapolations from accelerator data to air shower energies and investigate their impact on the corresponding air shower predictions. To explore the effect of different extrapolations by hadronic interaction models we developed an ad hoc model. This ad hoc model is based on the modification of the output of standard hadronic interaction event generators within the air shower simulation process and allows us to study the impact of changing interaction features on the air shower development. In a systematic study we demonstrate the resulting changes of important air shower observables and also discuss them in terms of the predictions of the Heitler model of air shower cascades. It is found that the results of our ad hoc modifications are, to a large extend, independent of the choice of the underlying hadronic interaction model.

Ralf Ulrich; Ralph Engel; Michael Unger

2010-10-20T23:59:59.000Z

113

IceCube-Plus: An Ultra-High Energy Neutrino Telescope  

E-Print Network [OSTI]

While the first kilometer-scale neutrino telescope, IceCube, is under constructi on, alternative plans exist to build even larger detectors that will, however, b e limited by a much higher neutrino energy threshold of 10 PeV or higher rather than 10 to 100 GeV. These future projects detect radio and acoustic pulses as w ell as air showers initiated by ultra-high energy neutrinos. As an alternative, we here propose an expansion of IceCube, using the same strings, placed on a gri d with a spacing of order 500 m. Unlike other proposals, the expanded detector uses methods that are understood and calibrated on atmospheric neutrinos. Atmosp heric neutrinos represent the only background at the energies under consideratio n and is totally negligible. Also, the cost of such a detector is understood. We conclude that supplementing the 81 IceCube strings with a modest number of addi tional strings spaced at large distances can almost double the effective volume of the detector. Doubling the number of strings on a 800 m ...

Halzen, F; Halzen, Francis; Hooper, Dan

2004-01-01T23:59:59.000Z

114

IceCube-Plus: An Ultra-High Energy Neutrino Telescope  

E-Print Network [OSTI]

While the first kilometer-scale neutrino telescope, IceCube, is under construction, alternative plans exist to build even larger detectors that will, however, b e limited by a much higher neutrino energy threshold of 10 PeV or higher rather than 10 to 100 GeV. These future projects detect radio and acoustic pulses as w ell as air showers initiated by ultra-high energy neutrinos. As an alternative, we here propose an expansion of IceCube, using the same strings, placed on a gri d with a spacing of order 500 m. Unlike other proposals, the expanded detector uses methods that are understood and calibrated on atmospheric neutrinos. Atmosp heric neutrinos represent the only background at the energies under consideratio n and is totally negligible. Also, the cost of such a detector is understood. We conclude that supplementing the 81 IceCube strings with a modest number of addi tional strings spaced at large distances can almost double the effective volume of the detector. Doubling the number of strings on a 800 m grid can deliver a d etector that this a factor of 5 larger for horizontal muons at modest cost.

Francis Halzen; Dan Hooper

2003-12-22T23:59:59.000Z

115

Are gamma-ray bursts the sources of ultra-high energy cosmic rays?  

Science Journals Connector (OSTI)

Abstract We reconsider the possibility that gamma-ray bursts (GRBs) are the sources of the ultra-high energy cosmic rays (UHECRs) within the internal shock model, assuming a pure proton composition of the UHECRs. For the first time, we combine the information from gamma-rays, cosmic rays, prompt neutrinos, and cosmogenic neutrinos quantitatively in a joint cosmic ray production and propagation model, and we show that the information on the cosmic energy budget can be obtained as a consequence. In addition to the neutron model, we consider alternative scenarios for the cosmic ray escape from the GRBs, i.e., that cosmic rays can leak from the sources. We find that the dip model, which describes the ankle in UHECR observations by the pair production dip, is strongly disfavored in combination with the internal shock model because (a) unrealistically high baryonic loadings (energy in protons versus energy in electrons/gamma-rays) are needed for the individual \\{GRBs\\} and (b) the prompt neutrino flux easily overshoots the corresponding neutrino bound. On the other hand, \\{GRBs\\} may account for the \\{UHECRs\\} in the ankle transition model if cosmic rays leak out from the source at the highest energies. In that case, we demonstrate that future neutrino observations can efficiently test most of the parameter space unless the baryonic loading is much larger than previously anticipated.

Philipp Baerwald; Mauricio Bustamante; Walter Winter

2015-01-01T23:59:59.000Z

116

The First Limits on the Ultra-high Energy Neutrino Fluence from Gamma-Ray Bursts  

Science Journals Connector (OSTI)

We set the first limits on the ultra-high energy (UHE) neutrino fluence at energies greater than 109?GeV from gamma-ray bursts (GRBs) based on data from the second flight of the Antarctic Impulsive Transient Antenna (ANITA). During the 31 day flight of ANITA-II, 26 GRBs were recorded by Swift or Fermi. Of these, we analyzed the 12 GRBs which occurred during quiet periods when the payload was away from anthropogenic activity. In a blind analysis, we observe 0 events on a total background of 0.0044 events in the combined prompt window for all 12 low-background bursts. We also observe 0 events from the remaining 14 bursts. We place a 90% confidence level limit on the E ?4 prompt neutrino fluence between 108?GeV E 12?GeV of E 4? = 2.5 ? 1017?GeV3?cm?2 from GRB090107A. This is the first reported limit on the UHE neutrino fluence from GRBs above 109?GeV, and the strongest limit above 108?GeV.

A. G. Vieregg; K. Palladino; P. Allison; B. M. Baughman; J. J. Beatty; K. Belov; D. Z. Besson; S. Bevan; W. R. Binns; C. Chen; P. Chen; J. M. Clem; A. Connolly; M. Detrixhe; D. De Marco; P. F. Dowkontt; M. DuVernois; P. W. Gorham; E. W. Grashorn; B. Hill; S. Hoover; M. Huang; M. H. Israel; A. Javaid; K. M. Liewer; S. Matsuno; B. C. Mercurio; C. Miki; M. Mottram; J. Nam; R. J. Nichol; A. Romero-Wolf; L. Ruckman; D. Saltzberg; D. Seckel; G. S. Varner; Y. Wang

2011-01-01T23:59:59.000Z

117

Constraints on the flux of Ultra-High Energy neutrinos from WSRT observations  

SciTech Connect (OSTI)

Context. Ultra-high energy (UHE) neutrinos and cosmic rays initiate particle cascades underneath theMoon?s surface. These cascades have a negative charge excess and radiate Cherenkov radio emission in a process known as the Askaryan effect. The optimal frequencywindow for observation of these pulses with radio telescopes on the Earth is around 150 MHz. Aims. By observing the Moon with the Westerbork Synthesis Radio Telescope array we are able to set a new limit on the UHEneutrino flux. Methods. The PuMa II backend is used to monitor the Moon in 4 frequency bands between 113 and 175 MHz with a samplingfrequency of 40 MHz. The narrowband radio interference is digitally filtered out and the dispersive effect of the Earth?s ionosphere is compensated for. A trigger system is implemented to search for short pulses. By inserting simulated pulses in the raw data, thedetection efficiency for pulses of various strength is calculated. Results. With 47.6 hours of observation time, we are able to set a limit onthe UHE neutrino flux. This new limit is an order of magnitude lower than existing limits. In the near future, the digital radio array LOFAR will be used to achieve an even lower limit.

Scholten, O.; Bacelar, J.; Braun, R.; de Bruyn, A.G.; Falcke, H.; Singh, K.; Stappers, B.; Strom, R.G.; al Yahyaoui, R.

2010-04-02T23:59:59.000Z

118

Development of Ultra High Gradient and High Q{sub 0} Superconducting Radio Frequency Cavities  

SciTech Connect (OSTI)

We report on the recent progress at Jefferson Lab in developing ultra high gradient and high Q{sub 0} superconducting radio frequency (SRF) cavities for future SRF based machines. A new 1300 MHz 9-cell prototype cavity is being fabricated. This cavity has an optimized shape in terms of the ratio of the peak surface field (both magnetic and electric) to the acceleration gradient, hence the name low surface field (LSF) shape. The goal of the effort is to demonstrate an acceleration gradient of 50 MV/m with Q{sub 0} of 10{sup 10} at 2 K in a 9-cell SRF cavity. Fine-grain niobium material is used. Conventional forming, machining and electron beam welding method are used for cavity fabrication. New techniques are adopted to ensure repeatable, accurate and inexpensive fabrication of components and the full assembly. The completed cavity is to be first mechanically polished to a mirror-finish, a newly acquired in-house capability at JLab, followed by the proven ILC-style processing recipe established already at JLab. In parallel, new single-cell cavities made from large-grain niobium material are made to further advance the cavity treatment and processing procedures, aiming for the demonstration of an acceleration gradient of 50 MV/m with Q{sub 0} of 2?10{sup 10} at 2K.

Geng, Rongli [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Clemens, William A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Follkie, James E. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Harris, Teena M. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Kushnick, Peter W. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Machie, Danny [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Martin, Robert E. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Palczewski, Ari D. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Perry, Era A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Slack, Gary L. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Williams, R. S. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Adolphsen, C. [SLAC, Menlo Park, California, (United States); Li, Z. [SLAC, Menlo Park, California, (United States); Hao, J. K. [Peking University, Beijing (China); Li, Y. M. [Peking University, Beijing (China); Liu, K. X. [Peking University, Beijing (China)

2013-06-01T23:59:59.000Z

119

TeV Burst of Gamma-Ray Bursts and Ultra High Energy Cosmic Rays  

E-Print Network [OSTI]

Some recent experiments detecting very high energy (VHE) gamma-rays above 10-20 TeV independently reported VHE bursts for some of bright gamma-ray bursts (GRBs). If these signals are truly from GRBs, these GRBs must emit a much larger amount of energy as VHE gamma-rays than in the ordinary photon energy range of GRBs (keV-MeV). We show that such extreme phenomena can be reasonably explained by synchrotron radiation of protons accelerated to \\sim 10^{20-21} eV, which has been predicted by Totani (1998a). Protons seem to carry about (m_p/m_e) times larger energy than electrons, and hence the total energy liberated by one GRB becomes as large as \\sim 10^{56} (\\Delta \\Omega / 4 \\pi) ergs. Therefore a strong beaming of GRB emission is highly likely. Extension of the VHE spectrum beyond 20 TeV gives a nearly model-independent lower limit of the Lorentz factor of GRBs, as $\\gamma \\gtilde 500$. Furthermore, our model gives the correct energy range and time variability of ordinary keV-MeV gamma-rays of GRBs by synchrotron radiation of electrons. Therefore the VHE bursts of GRBs strongly support the hypothesis that ultra high energy cosmic rays observed on the Earth are produced by GRBs.

Tomonori Totani

1998-10-14T23:59:59.000Z

120

Search for Ultra High-Energy Neutrinos with AMANDA-II  

SciTech Connect (OSTI)

A search for diffuse neutrinos with energies in excess of 10{sup 5} GeV is conducted with AMANDA-II data recorded between 2000 and 2002. Above 10{sup 7} GeV, the Earth is essentially opaque to neutrinos. This fact, combined with the limited overburden of the AMANDA-II detector (roughly 1.5 km), concentrates these ultra high-energy neutrinos at the horizon. The primary background for this analysis is bundles of downgoing, high-energy muons from the interaction of cosmic rays in the atmosphere. No statistically significant excess above the expected background is seen in the data, and an upper limit is set on the diffuse all-flavor neutrino flux of E{sup 2} {Phi}{sub 90%CL} < 2.7 x 10{sup -7} GeV cm{sup -2}s{sup -1} sr{sup -1} valid over the energy range of 2 x 10{sup 5} GeV to 10{sup 9} GeV. A number of models which predict neutrino fluxes from active galactic nuclei are excluded at the 90% confidence level.

IceCube Collaboration; Klein, Spencer; Ackermann, M.

2007-11-19T23:59:59.000Z

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121

Diffusive Propagation of Ultra-High-Energy Cosmic Rays and the Propagation Theorem  

Science Journals Connector (OSTI)

We present a detailed analytical study of the propagation of ultra-high-energy (UHE) particles in extragalactic magnetic fields. The crucial parameter that affects the diffuse spectrum is the separation between sources. In the case of a uniform distribution of sources with a separation between them much smaller than all characteristic propagation lengths, the diffuse spectrum of UHE particles has a universal form, independent of the mode of propagation. This statement has the status of theorem. The proof is obtained using the particle number conservation during propagation and also using the kinetic equation for the propagation of UHE particles. This theorem can be also proved with the help of the diffusion equation. In particular, it is shown numerically how the diffuse fluxes converge to this universal spectrum, when the separation between sources diminishes. We study also the analytic solution of the diffusion equation in weak and strong magnetic fields with energy losses taken into account. In the case of strong magnetic fields and for a separation between sources large enough, the GZK cutoff can practically disappear, as it has been found early in numerical simulations. In practice, however, the source luminosities required are too large for this possibility.

R. Aloisio; V. Berezinsky

2004-01-01T23:59:59.000Z

122

The Role and Detectability of the Charm Contribution to Ultra High Energy Neutrino Fluxes  

E-Print Network [OSTI]

It is widely believed that charm meson production and decay may play an important role in high energy astrophysical sources of neutrinos, especially those that are baryon-rich, providing an environment conducive to pp interactions. Using slow-jet supernovae (SJS) as an example of such a source, we study the detectability of high-energy neutrinos, paying particular attention to those produced from charmed-mesons. We highlight important distinguishing features in the ultra-high energy neutrino flux which would act as markers for the role of charm in the source. In particular, charm leads to significant event rates at higher energies, after the conventional (pi, K) neutrino fluxes fall off. We calculate event rates both for a nearby single source and for diffuse SJS fluxes for an IceCube-like detector. By comparing muon event rates for the conventional and prompt fluxes in different energy bins, we demonstrate the striking energy dependence in the rates induced by the presence of charm. We also show that it lead...

Gandhi, Raj; Watanabe, Atsushi

2009-01-01T23:59:59.000Z

123

Atcitty_Ultra-HighSIC_RD100v8.2.indd  

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

R R & D 1 0 0 * 2 0 1 1 * E N T R Y S U B M I S S I O N 1. DEVELOPER INFORMATION A. Primary submitting organization GeneSiC Semiconductor Inc. Contact Name: Dr. Ranbir Singh Address: 43670 Trade Center Place, Suite 155 City/State: Dulles, VA Zip/Postal Code: 20166 Country: USA Phone: 703-996-8200 x105 Fax: 703-373-6918 Email: ranbir.singh@genesicsemi.com Web URL: www.genesicsemi.com B. Joint submitters Sandia National Laboratories Describe role of joint submitter in development of technology: Reviewing/Mentoring Address: PO Box 5800 MS 0614 City: Albuquerque State: NM Zip/Postal: 87185 Country: USA Web URL: www.sandia.gov Contact Name: Dr. Stanley Atcitty Phone: 505-284-2701 Fax: 505-844-6972 Email: satcitt@sandia.gov ULTRA HIGH VOLTAGE SILICON CARBIDE THYRISTOR 3 S A N D I A N A T I O N A L L

124

HOW MANY ULTRA-HIGH ENERGY COSMIC RAYS COULD WE EXPECT FROM CENTAURUS A?  

SciTech Connect (OSTI)

The Pierre Auger Observatory has associated a few ultra-high energy cosmic rays (UHECRs) with the direction of Centaurus A. This source has been deeply studied in radio, infrared, X-ray, and {gamma}-rays (MeV-TeV) because it is the nearest radio-loud active galactic nucleus. Its spectral energy distribution or spectrum shows two main peaks, the low-energy peak, at an energy of 10{sup -2} eV, and the high-energy peak, at about 150 keV. There is also a faint very high energy (VHE; E {>=} 100 GeV) {gamma}-ray emission fully detected by the High Energy Stereoscopic System experiment. In this work, we describe the entire spectrum: the two main peaks with a synchrotron/synchrotron self-Compton model, and the VHE emission with a hadronic model. We consider p{gamma} and pp interactions. For the p{gamma} interaction, we assume that the target photons are those produced at 150 keV in leptonic processes. On the other hand, for the pp interaction we consider as targets the thermal particle densities in the lobes. Requiring a satisfactory description of the spectra at very high energies with p{gamma} interaction, we obtain an excessive luminosity in UHECRs (even exceeding the Eddington luminosity). However, when considering the pp interaction to describe the {gamma}-spectrum, the number of UHECRs obtained is in agreement with Pierre Auger observations. We also calculate the possible neutrino signal from pp interactions on a Km{sup 3} neutrino telescope using Monte Carlo simulations.

Fraija, N.; Gonzalez, M. M.; Perez, M. [Instituto de Astronomia, Universidad Nacional Autonoma de Mexico, Circuito Exterior, C.U., A. Postal 70-264, 04510 Mexico D.F. (Mexico); Marinelli, A., E-mail: nifraija@astro.unam.mx, E-mail: magda@astro.unam.mx, E-mail: jguillen@astro.unam.mx, E-mail: antonio.marinelli@fisica.unam.mx [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Circuito Exterior, C.U., A. Postal 70-264, 04510 Mexico D.F. (Mexico)

2012-07-01T23:59:59.000Z

125

Surface characterization of ordered intermetallic PtBi(001) surfaces by ultra-high vacuumelectrochemistry (UHVEC)  

Science Journals Connector (OSTI)

Surface preparation and characterization of an ordered intermetallic PtBi(001) single crystal was performed by a combination of surface-sensitive electron spectroscopic techniques under ultra-high vacuum (UHV) conditions and conventional electrochemistry (EC). The atomic concentration of the clean surface was estimated (quantitative Auger analysis) as 54at% Pt and 46at% Bi; the LEED pattern exhibited a (1נ1) structure. These results are in good agreement with expectations for a Pt-terminated PtBi(001) crystal surface. The electrochemical studies of the clean, well-ordered and smooth PtBi(001) single crystal were carried out in an H2SO4 supporting electrolyte and indicated that the electrode surface is Pt-terminated with a behavior similar to that of a pure Pt electrode. However, the intermetallic phase was found to be more prone to surface oxidation in the studied potential window (?0.30V to +1.25V vs. Ag/AgCl (satd NaCl)). Chemisorption of SO 4 2 - / HSO 4 - species was observed at potentials positive of the open circuit potential (OCP). Cycling in a supporting electrolyte gave rise to roughening of the electrode surface. This change is due to the presence of the chemisorbed species on the electrode surface.

Jean Sanabria-Chinchilla; Hideki Abe; Francis J. DiSalvo; Hctor D. Abrua

2008-01-01T23:59:59.000Z

126

Analysis of different modes of low temperature combustion by ultra-high EGR and modulated kinetics in a heavy duty diesel engine  

Science Journals Connector (OSTI)

Abstract Simulation is performed to analyze the characteristics of different modes of low temperature combustion (LTC), by ultra-high exhaust gas recirculation (EGR) (UHE) and modulated kinetics (MK) in a CI engine. The physical models and numerical methods in KIVA-CMC are validated against measured pressure traces and NOx, CO and PM emissions for selected test cases. It is shown that the two LTC modes involve different fuel evaporation histories and turbulent flame structures in the tested ranges of EGR rates and injection timings. LTC is confirmed with simultaneous reduction of \\{NOx\\} and PM above the critical EGR rate and SOI timing in the UHE and the MK mode respectively. The UHE mode at the EGR rate 68% shows conditional temperature between 1000K and 1600K, while the MK mode at the EGR rate 48% shows conditional temperature distribution between 1000K and 2200K. It is shown that the temperature is the most sensitive parameter to suppress \\{NOx\\} in the UHE mode, while a longer ignition delay leads to more homogeneous mixture to result in reduced CO and PM in the MK mode.

Youngjae Lee; Kang Y. Huh

2014-01-01T23:59:59.000Z

127

Point-like gamma ray sources as signatures of distant accelerators of ultra high energy cosmic rays  

E-Print Network [OSTI]

We discuss the possibility of observing distant accelerators of ultra high energy cosmic rays in synchrotron gamma rays. Protons propagating away from their acceleration sites produce extremely energetic electrons during photo-pion interactions with cosmic microwave background photons. If the accelerator is embedded in a magnetized region, these electrons will emit high energy synchrotron radiation. The resulting synchrotron source is expected to be point-like and detectable in the GeV-TeV energy range if the magnetic field is at the nanoGauss level.

S. Gabici; F. A. Aharonian

2005-05-22T23:59:59.000Z

128

Smaller Footprint Drilling System for Deep and Hard Rock Environments; Feasibility of Ultra-High-Speed Diamond Drilling  

SciTech Connect (OSTI)

The two phase program addresses long-term developments in deep well and hard rock drilling. TerraTek believes that significant improvements in drilling deep hard rock will be obtained by applying ultra-high rotational speeds (greater than 10,000 rpm). The work includes a feasibility of concept research effort aimed at development that will ultimately result in the ability to reliably drill ''faster and deeper'' possibly with smaller, more mobile rigs. The principle focus is on demonstration testing of diamond bits rotating at speeds in excess of 10,000 rpm to achieve high rate of penetration (ROP) rock cutting with substantially lower inputs of energy and loads. The significance of the ultra-high rotary speed drilling system is the ability to drill into rock at very low weights on bit and possibly lower energy levels. The drilling and coring industry today does not practice this technology. The highest rotary speed systems in oil field and mining drilling and coring today run less than 10,000 rpm--usually well below 5,000 rpm. This document details the progress to date on the program entitled ''Smaller Footprint Drilling System for Deep and Hard Rock Environments: Feasibility of Ultra-High-Speed Diamond Drilling'' for the period starting 1 October 2004 through 30 September 2005. Additionally, research activity from 1 October 2005 through 28 February 2006 is included in this report: (1) TerraTek reviewed applicable literature and documentation and convened a project kick-off meeting with Industry Advisors in attendance. (2) TerraTek designed and planned Phase I bench scale experiments. Some difficulties continue in obtaining ultra-high speed motors. Improvements have been made to the loading mechanism and the rotational speed monitoring instrumentation. New drill bit designs have been provided to vendors for production. A more consistent product is required to minimize the differences in bit performance. A test matrix for the final core bit testing program has been completed. (3) TerraTek is progressing through Task 3 ''Small-scale cutting performance tests''. (4) Significant testing has been performed on nine different rocks. (5) Bit balling has been observed on some rock and seems to be more pronounces at higher rotational speeds. (6) Preliminary analysis of data has been completed and indicates that decreased specific energy is required as the rotational speed increases (Task 4). This data analysis has been used to direct the efforts of the final testing for Phase I (Task 5). (7) Technology transfer (Task 6) has begun with technical presentations to the industry (see Judzis).

Arnis Judzis; Alan Black; Homer Robertson

2006-03-01T23:59:59.000Z

129

Bounds on the density of sources of ultra-high energy cosmic rays from the Pierre Auger Observatory  

SciTech Connect (OSTI)

We derive lower bounds on the density of sources of ultra-high energy cosmic rays from the lack of significant clustering in the arrival directions of the highest energy events detected at the Pierre Auger Observatory. The density of uniformly distributed sources of equal intrinsic intensity was found to be larger than ? (0.06?5) 10{sup ?4} Mpc{sup ?3} at 95% CL, depending on the magnitude of the magnetic deflections. Similar bounds, in the range (0.2?7) 10{sup ?4} Mpc{sup ?3}, were obtained for sources following the local matter distribution.

Collaboration: Pierre Auger Collaboration

2013-05-01T23:59:59.000Z

130

Ultra-High Efficiency and Low-Emissions Combustion Technology for Manufacturing Industries  

SciTech Connect (OSTI)

The purpose of this research was to develop and test a transformational combustion technology for high temperature furnaces to reduce the energy intensity and carbon footprint of U.S. manufacturing industries such as steel, aluminum, glass, metal casting, and petroleum refining. A new technology based on internal and/or external Flue Gas Recirculation (FGR) along with significant enhancement in flame radiation was developed. It produces "Radiative Flameless Combustion (RFC)" and offers tremendous energy efficiency and pollutant reduction benefits over and above the now popular "flameless combustion." It will reduce the energy intensity (or fuel consumption per unit system output) by more than 50% and double the furnace productivity while significantly reducing pollutants and greenhouse gas emissions (10^3 times reduction in NOx and 10 times reduction in CO & hydrocarbons and 3 times reduction in CO2). Product quality improvements are also expected due to uniform radiation, as well as, reduction in scale/dross formation is expected because of non-oxidative atmosphere. RFC is inexpensive, easy to implement, and it was successfully tested in a laboratory-scale furnace at the University of Michigan during the course of this work. A first-ever theory with gas and particulate radiation was also developed. Numerical programs were also written to design an industrial-scale furnace. Nine papers were published (or are in the process of publication). We believe that this early stage research adequately proves the concept through laboratory experiments, modeling and computational models. All this work is presented in the published papers. Important conclusions of this work are: (1) It was proved through experimental measurements that RFC is not only feasible but a very beneficial technology. (2) Theoretical analysis of RFC was done in (a) spatially uniform strain field and (b) a planar momentum jet where the strain rate is neither prescribed nor uniform. Four important non-dimensional parameters controlling RFC in furnaces were identified. These are: (i) The Boltzmann number; (ii) The Damkohler number, (iii) The dimensionless Arrhenius number, and (iv) The equivalence ratio. Together they define the parameter space where RFC is possible. It was also found that the Damkohler number must be small for RFC to exist and that the Boltzmann number expands the RFC domain. The experimental data obtained during the course of this work agrees well with the predictions made by the theoretical analysis. Interestingly, the equivalence ratio dependence shows that it is easier to establish RFC for rich mixtures than for lean mixtures. This was also experimentally observed. Identifying the parameter space for RFC is necessary for controlling the RFC furnace operation. It is hoped that future work will enable the methodology developed here to be applied to the operation of real furnaces, with consequent improvement in efficiency and pollutant reduction. To reiterate, the new furnace combustion technology developed enables intense radiation from combustion products and has many benefits: (i) Ultra-High Efficiency and Low-Emissions; (ii) Uniform and intense radiation to substantially increase productivity; (iii) Oxygen-free atmosphere to reduce dross/scale formation; (iv) Provides multi-fuel capability; and (v) Enables carbon sequestration if pure oxygen is used for combustion.

Atreya, Arvind

2013-04-15T23:59:59.000Z

131

Surface Anchoring of Nematic Phase on Carbon Nanotubes: Nanostructure of Ultra-High Temperature Materials  

SciTech Connect (OSTI)

Nuclear energy is a dependable and economical source of electricity. Because fuel supply sources are available domestically, nuclear energy can be a strong domestic industry that can reduce dependence on foreign energy sources. Commercial nuclear power plants have extensive security measures to protect the facility from intruders [1]. However, additional research efforts are needed to increase the inherent process safety of nuclear energy plants to protect the public in the event of a reactor malfunction. The next generation nuclear plant (NGNP) is envisioned to utilize a very high temperature reactor (VHTR) design with an operating temperature of 650-1000?°C [2]. One of the most important safety design requirements for this reactor is that it must be inherently safe, i.e., the reactor must shut down safely in the event that the coolant flow is interrupted [2]. This next-generation Gen IV reactor must operate in an inherently safe mode where the off-normal temperatures may reach 1500?°C due to coolant-flow interruption. Metallic alloys used currently in reactor internals will melt at such temperatures. Structural materials that will not melt at such ultra-high temperatures are carbon/graphtic fibers and carbon-matrix composites. Graphite does not have a measurable melting point; it is known to sublime starting about 3300?°C. However, neutron radiation-damage effects on carbon fibers are poorly understood. Therefore, the goal of this project is to obtain a fundamental understanding of the role of nanotexture on the properties of resulting carbon fibers and their neutron-damage characteristics. Although polygranular graphite has been used in nuclear environment for almost fifty years, it is not suitable for structural applications because it do not possess adequate strength, stiffness, or toughness that is required of structural components such as reaction control-rods, upper plenum shroud, and lower core-support plate [2,3]. For structural purposes, composites consisting of strong carbon fibers embedded in a carbon matrix are needed. Such carbon/carbon (C/C) composites have been used in aerospace industry to produce missile nose cones, space shuttle leading edge, and aircraft brake-pads. However, radiation-tolerance of such materials is not adequately known because only limited radiation studies have been performed on C/C composites, which suggest that pitch-based carbon fibers have better dimensional stability than that of polyacrylonitrile (PAN) based fibers [4]. The thermodynamically-stable state of graphitic crystalline packing of carbon atoms derived from mesophase pitch leads to a greater stability during neutron irradiation [5]. The specific objectives of this project were: (i) to generating novel carbonaceous nanostructures, (ii) measure extent of graphitic crystallinity and the extent of anisotropy, and (iii) collaborate with the Carbon Materials group at Oak Ridge National Lab to have neutron irradiation studies and post-irradiation examinations conducted on the carbon fibers produced in this research project.

Ogale, Amod A

2012-04-27T23:59:59.000Z

132

On LiF:Mg,Cu,P and LiF:Mg,Ti phosphors high & ultra-high dose features  

E-Print Network [OSTI]

LiF:Mg,Ti and LiF:Mg,Cu,P are well known thermoluminescence (TL) dosimetry materials since many years. A few years ago their properties seemed well known and it was widely believed that they are not suitable for the measurement of doses above the saturation level of the TL signal, which for both materials occur at about 1 kGy. The high-dose high-temperature TL emission of LiF:Mg,Cu,P observed at the IFJ in 2006, which above 30 kGy takes the form of the so-called TL peak B, opened the way to use this material for measuring the dose in the high and ultra-high range, in particular for the monitoring of ionizing radiation around the essential electronic elements of high-energy accelerators, also fission and fusion facilities, as well as for emergency dosimetry. This discovery initiated studies of high and ultra-high dose characteristics of both of these phosphors, which turned out to be significantly different in many aspects. These studies not only strive to refine the method for measuring high doses based on th...

Obryk, Barbara; de Barros, Vinicius S; Guzzo, Pedro L; Bilski, Pawe?

2013-01-01T23:59:59.000Z

133

SMALLER FOOTPRINT DRILLING SYSTEM FOR DEEP AND HARD ROCK ENVIRONMENTS; FEASIBILITY OF ULTRA-HIGH SPEED DIAMOND DRILLING  

SciTech Connect (OSTI)

The two phase program addresses long-term developments in deep well and hard rock drilling. TerraTek believes that significant improvements in drilling deep hard rock will be obtained by applying ultra-high (greater than 10,000 rpm) rotational speeds. The work includes a feasibility of concept research effort aimed at development and test results that will ultimately result in the ability to reliably drill ''faster and deeper'' possibly with rigs having a smaller footprint to be more mobile. The principle focus is on demonstration testing of diamond bits rotating at speeds in excess of 10,000 rpm to achieve high rate of penetration rock cutting with substantially lower inputs of energy and loads. The project draws on TerraTek results submitted to NASA's ''Drilling on Mars'' program. The objective of that program was to demonstrate miniaturization of a robust and mobile drilling system that expends small amounts of energy. TerraTek successfully tested ultrahigh speed ({approx}40,000 rpm) small kerf diamond coring. Adaptation to the oilfield will require innovative bit designs for full hole drilling or continuous coring and the eventual development of downhole ultra-high speed drives. For domestic operations involving hard rock and deep oil and gas plays, improvements in penetration rates is an opportunity to reduce well costs and make viable certain field developments. An estimate of North American hard rock drilling costs is in excess of $1,200 MM. Thus potential savings of $200 MM to $600 MM are possible if drilling rates are doubled [assuming bit life is reasonable]. The net result for operators is improved profit margin as well as an improved position on reserves. The significance of the ''ultra-high rotary speed drilling system'' is the ability to drill into rock at very low weights on bit and possibly lower energy levels. The drilling and coring industry today does not practice this technology. The highest rotary speed systems in oil field and mining drilling and coring today run less than 10,000 rpm--usually well below 5,000 rpm. This document details the progress to date on the program entitled ''SMALLER FOOTPRINT DRILLING SYSTEM FOR DEEP AND HARD ROCK ENVIRONMENTS; FEASIBILITY OF ULTRA-HIGH SPEED DIAMOND DRILLING'' for the period starting June 23, 2003 through September 30, 2004. (1) TerraTek has reviewed applicable literature and documentation and has convened a project kick-off meeting with Industry Advisors in attendance. (2) TerraTek has designed and planned Phase I bench scale experiments. Some difficulties in obtaining ultra-high speed motors for this feasibility work were encountered though they were sourced mid 2004. (3) TerraTek is progressing through Task 3 ''Small-scale cutting performance tests''. Some improvements over early NASA experiments have been identified.

Alan Black; Arnis Judzis

2004-10-01T23:59:59.000Z

134

SMALLER FOOTPRINT DRILLING SYSTEM FOR DEEP AND HARD ROCK ENVIRONMENTS; FEASIBILITY OF ULTRA-HIGH SPEED DIAMOND DRILLING  

SciTech Connect (OSTI)

The two phase program addresses long-term developments in deep well and hard rock drilling. TerraTek believes that significant improvements in drilling deep hard rock will be obtained by applying ultra-high (greater than 10,000 rpm) rotational speeds. The work includes a feasibility of concept research effort aimed at development and test results that will ultimately result in the ability to reliably drill ''faster and deeper'' possibly with rigs having a smaller footprint to be more mobile. The principle focus is on demonstration testing of diamond bits rotating at speeds in excess of 10,000 rpm to achieve high rate of penetration rock cutting with substantially lower inputs of energy and loads. The project draws on TerraTek results submitted to NASA's ''Drilling on Mars'' program. The objective of that program was to demonstrate miniaturization of a robust and mobile drilling system that expends small amounts of energy. TerraTek successfully tested ultrahigh speed ({approx}40,000 rpm) small kerf diamond coring. Adaptation to the oilfield will require innovative bit designs for full hole drilling or continuous coring and the eventual development of downhole ultra-high speed drives. For domestic operations involving hard rock and deep oil and gas plays, improvements in penetration rates is an opportunity to reduce well costs and make viable certain field developments. An estimate of North American hard rock drilling costs is in excess of $1,200 MM. Thus potential savings of $200 MM to $600 MM are possible if drilling rates are doubled [assuming bit life is reasonable]. The net result for operators is improved profit margin as well as an improved position on reserves. The significance of the ''ultra-high rotary speed drilling system'' is the ability to drill into rock at very low weights on bit and possibly lower energy levels. The drilling and coring industry today does not practice this technology. The highest rotary speed systems in oil field and mining drilling and coring today run less than 10,000 rpm--usually well below 5,000 rpm. This document details the progress to date on the program entitled ''SMALLER FOOTPRINT DRILLING SYSTEM FOR DEEP AND HARD ROCK ENVIRONMENTS; FEASIBILITY OF ULTRA-HIGH SPEED DIAMOND DRILLING'' for the period starting June 23, 2003 through September 30, 2004. TerraTek has reviewed applicable literature and documentation and has convened a project kick-off meeting with Industry Advisors in attendance. TerraTek has designed and planned Phase I bench scale experiments. Some difficulties in obtaining ultra-high speed motors for this feasibility work were encountered though they were sourced mid 2004. TerraTek is progressing through Task 3 ''Small-scale cutting performance tests''. Some improvements over early NASA experiments have been identified.

Alan Black; Arnis Judzis

2004-10-01T23:59:59.000Z

135

ARM - PI Product - Direct Aerosol Forcing Uncertainty  

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

136

Ultra-high quality factors in superconducting niobium cavities in ambient magnetic fields up to 190 mG  

E-Print Network [OSTI]

Ambient magnetic field, if trapped in the penetration depth, leads to the residual resistance and therefore sets the limit for the achievable quality factors in superconducting niobium resonators for particle accelerators. Here we show that a complete expulsion of the magnetic flux can be performed and leads to: 1) record quality factors $Q > 2\\times10^{11}$ up to accelerating gradient of 22 MV/m; 2) $Q\\sim3\\times10^{10}$ at 2 K and 16 MV/m in up to 190 mG magnetic fields. This is achieved by large thermal gradients at the normal/superconducting phase front during the cooldown. Our findings open up a way to ultra-high quality factors at low temperatures and show an alternative to the sophisticated magnetic shielding implemented in modern superconducting accelerators.

Romanenko, A; Crawford, A C; Sergatskov, D A; Melnychuk, O

2014-01-01T23:59:59.000Z

137

Exploration of coal-based pitch precursors for ultra-high thermal conductivity graphite fibers. Final report  

SciTech Connect (OSTI)

Goal was to explore the utility of coal-based pitch precursors for use in ultra high thermal conductivity carbon (graphite) fibers. From graphite electrode experience, it was established that coal-based pitches tend to form more highly crystalline graphite at lower temperatures. Since the funding was limited to year 1 effort of the 3 year program, the goal was only partially achieved. The coal-base pitches can form large domain mesophase in spite of high N and O contents. The mesophase reactivity test performed on one of the variants of coal-based pitch (DO84) showed that it was not a good candidate for carbon fiber processing. Optimization of WVU`s isotropic pitch process is required to tailor the pitch for carbon fiber processing. The hetero atoms in the coal pitch need to be reduced to improve mesophase formation.

Deshpande, G.V. [Amoco Performance Products, Inc., Alpharetta, GA (United States)

1996-12-27T23:59:59.000Z

138

Ultra-High Pressure Driver and Nozzle Survivability in the RDHWT/MARIAH II Hypersonic Wind Tunnel  

SciTech Connect (OSTI)

An ultra-high pressure device provides a high enthalpy (> 2500 kJ/kg), low entropy (< 5 kJ/kg-K) air source for the RDHWT/MARIAH II Program Medium Scale Hypersonic Wind Tunnel. The design uses stagnation conditions of 2300 MPa (330,000 Psi) and 750 K (900 F) in a radial configuration of intensifiers around an axial manifold to deliver pure air at 100 kg/s mass flow rates for run times suitable for aerodynamic, combustion, and test and evaluation applications. Helium injection upstream of the nozzle throat reduces the throat wall recovery temperature to about 1200 K and reduces the oxygen concentration at the nozzle wall.

Costantino, M.; Brown, G.; Raman, K.; Miles, R.; Felderman, J.

2000-06-02T23:59:59.000Z

139

From ultra-high vacuum to the electrochemical interface : x-ray scattering studies of model electrocatalysts.  

SciTech Connect (OSTI)

In-situ surface X-ray scattering (SXS) has become a powerful probe of the atomic structure at the metal-electrolyte interface. In this paper we describe an experiment in which a Pt(111) sample is prepared under ultra-high vacuum (UHV) conditions to have a p(2 x 2) oxygen layer adsorbed on the surface. The surface is then studied using SXS under UHV conditions before successive transfer to a bulk water environment and then to the electrochemical environment (0.1 M KOH solution) under an applied electrode potential. The Pt surface structure is examined in detail using crystal truncation rod (CTR) measurements under these different conditions. Finally, some suggestions for future experiments on alloy materials, using the same methodology, are proposed and discussed in relation to previous results.

Lucas, C. A.; Cormack, M.; Gallagher, M. E.; Brownrigg, A.; Thompson, P.; Fowler, B.; Grunder, Y.; Roy, J.; Stamenkovic, V.; Markovic, N. M.; Materials Science Division; Univ. of Liverpool; European Synchrotron Radiation Facility

2008-08-01T23:59:59.000Z

140

A diamond-based scanning probe spin sensor operating at low temperature in ultra-high vacuum  

SciTech Connect (OSTI)

We present the design and performance of an ultra-high vacuum (UHV) low temperature scanning probe microscope employing the nitrogen-vacancy color center in diamond as an ultrasensitive magnetic field sensor. Using this center as an atomic-size scanning probe has enabled imaging of nanoscale magnetic fields and single spins under ambient conditions. In this article we describe an experimental setup to operate this sensor in a cryogenic UHV environment. This will extend the applicability to a variety of molecular systems due to the enhanced target spin lifetimes at low temperature and the controlled sample preparation under UHV conditions. The instrument combines a tuning-fork based atomic force microscope (AFM) with a high numeric aperture confocal microscope and the facilities for application of radio-frequency (RF) fields for spin manipulation. We verify a sample temperature of <50 K even for strong laser and RF excitation and demonstrate magnetic resonance imaging with a magnetic AFM tip.

Schaefer-Nolte, E.; Wrachtrup, J. [Max-Planck Institute for Solid State Research, 70569 Stuttgart (Germany) [Max-Planck Institute for Solid State Research, 70569 Stuttgart (Germany); 3rd Institute of Physics and Research Center SCoPE, University Stuttgart, 70569 Stuttgart (Germany); Reinhard, F. [3rd Institute of Physics and Research Center SCoPE, University Stuttgart, 70569 Stuttgart (Germany)] [3rd Institute of Physics and Research Center SCoPE, University Stuttgart, 70569 Stuttgart (Germany); Ternes, M., E-mail: m.ternes@fkf.mpg.de [Max-Planck Institute for Solid State Research, 70569 Stuttgart (Germany); Kern, K. [Max-Planck Institute for Solid State Research, 70569 Stuttgart (Germany) [Max-Planck Institute for Solid State Research, 70569 Stuttgart (Germany); Institut de Physique de la Matire Condense, Ecole Polytechnique Fdrale de Lausanne, 1015 Lausanne (Switzerland)

2014-01-15T23:59:59.000Z

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" from the National Library of EnergyBeta (NLEBeta).
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to obtain the most current and comprehensive results.


141

Smaller Footprint Drilling System for Deep and Hard Rock Environments; Feasibility of Ultra-High-Speed Diamond Drilling  

SciTech Connect (OSTI)

The two phase program addresses long-term developments in deep well and hard rock drilling. TerraTek believes that significant improvements in drilling deep hard rock will be obtained by applying ultra-high rotational speeds (greater than 10,000 rpm). The work includes a feasibility of concept research effort aimed at development that will ultimately result in the ability to reliably drill ''faster and deeper'' possibly with smaller, more mobile rigs. The principle focus is on demonstration testing of diamond bits rotating at speeds in excess of 10,000 rpm to achieve high rate of penetration (ROP) rock cutting with substantially lower inputs of energy and loads. The significance of the ''ultra-high rotary speed drilling system'' is the ability to drill into rock at very low weights on bit and possibly lower energy levels. The drilling and coring industry today does not practice this technology. The highest rotary speed systems in oil field and mining drilling and coring today run less than 10,000 rpm-usually well below 5,000 rpm. This document details the progress at the end of Phase 1 on the program entitled ''Smaller Footprint Drilling System for Deep and Hard Rock Environments: Feasibility of Ultra-High-Speed Diamond Drilling'' for the period starting 1 March 2006 and concluding 30 June 2006. (Note: Results from 1 September 2005 through 28 February 2006 were included in the previous report (see Judzis, Black, and Robertson)). Summarizing the accomplished during Phase 1: {lg_bullet} TerraTek reviewed applicable literature and documentation and convened a project kickoff meeting with Industry Advisors in attendance (see Black and Judzis). {lg_bullet} TerraTek designed and planned Phase I bench scale experiments (See Black and Judzis). Some difficulties continued in obtaining ultra-high speed motors. Improvements were made to the loading mechanism and the rotational speed monitoring instrumentation. New drill bit designs were developed to provided a more consistent product with consistent performance. A test matrix for the final core bit testing program was completed. {lg_bullet} TerraTek concluded Task 3 ''Small-scale cutting performance tests.'' {sm_bullet} Significant testing was performed on nine different rocks. {sm_bullet} Five rocks were used for the final testing. The final tests were based on statistical design of experiments. {sm_bullet} Two full-faced bits, a small diameter and a large diameter, were run in Berea sandstone. {lg_bullet} Analysis of data was completed and indicates that there is decreased specific energy as the rotational speed increases (Task 4). Data analysis from early trials was used to direct the efforts of the final testing for Phase I (Task 5). {lg_bullet} Technology transfer (Task 6) was accomplished with technical presentations to the industry (see Judzis, Boucher, McCammon, and Black).

Arnis Judzis; Homer Robertson; Alan Black

2006-06-22T23:59:59.000Z

142

Coherence length of cosmic background radiation enlarges the attenuation length of the ultra-high energy proton  

E-Print Network [OSTI]

It is pointed out that an agreement of the one particle energy spectrum of the cosmic background radiation (CMBR) with Plank distribution of 2.725 [K] does not give a strong constraint on the coherence length of CMBR if the mean free path of CMBR is very long. The coherence length in this situation is estimated as a few times of $k_BT$. Due to this finite coherence length, the attenuation length of ultra-high energy cosmic rays (UHECR) is reduced in the $\\Delta $ resonance region,i.e., around $10^{20}$ [eV]. The small attenuation length makes the suppression of the flux of cosmic rays in this energy region less prominent than the naive estimation

Kenzo Ishikawa; Yutaka Tobita

2008-01-21T23:59:59.000Z

143

Reconstruction of Longitudinal Profiles of Ultra-High Energy Cosmic Ray Showers from Fluorescence and Cherenkov Light Measurements  

E-Print Network [OSTI]

We present a new method for the reconstruction of the longitudinal profile of extensive air showers induced by ultra-high energy cosmic rays. In contrast to the typically considered shower size profile, this method employs directly the ionization energy deposit of the shower particles in the atmosphere. Due to universality of the energy spectra of electrons and positrons, both fluorescence and Cherenkov light can be used simultaneously as signal to infer the shower profile from the detected light. The method is based on an analytic least-square solution for the estimation of the shower profile from the observed light signal. Furthermore, the extrapolation of the observed part of the profile with a Gaisser-Hillas function is discussed and the total statistical uncertainty of shower parameters like total energy and shower maximum is calculated.

M. Unger; B. R. Dawson; R. Engel; F. Schssler; R. Ulrich

2008-01-28T23:59:59.000Z

144

Application of slow-light photonic crystal structures for ultra-high speed all-optical analog-to-digital conversion  

E-Print Network [OSTI]

Application of slow-light photonic crystal structures for ultra-high speed all-optical analog circuits. Proposed usage of such controlled light speed devices includes buffers, synchronizer with the reduction of light speed), and slow-light all-optical nonlinear devices [9, 10] taking advantage

Park, Namkyoo

145

Smaller Footprint Drilling System for Deep and Hard Rock Environments; Feasibility of Ultra-High-Speed Diamond Drilling  

SciTech Connect (OSTI)

The two phase program addresses long-term developments in deep well and hard rock drilling. TerraTek believes that significant improvements in drilling deep hard rock will be obtained by applying ultra-high rotational speeds (greater than 10,000 rpm). The work includes a feasibility of concept research effort aimed at development that will ultimately result in the ability to reliably drill 'faster and deeper' possibly with smaller, more mobile rigs. The principle focus is on demonstration testing of diamond bits rotating at speeds in excess of 10,000 rpm to achieve high rate of penetration (ROP) rock cutting with substantially lower inputs of energy and loads. The significance of the 'ultra-high rotary speed drilling system' is the ability to drill into rock at very low weights on bit and possibly lower energy levels. The drilling and coring industry today does not practice this technology. The highest rotary speed systems in oil field and mining drilling and coring today run less than 10,000 rpm - usually well below 5,000 rpm. This document provides the progress through two phases of the program entitled 'Smaller Footprint Drilling System for Deep and Hard Rock Environments: Feasibility of Ultra-High-Speed Diamond Drilling' for the period starting 30 June 2003 and concluding 31 March 2009. The accomplishments of Phases 1 and 2 are summarized as follows: (1) TerraTek reviewed applicable literature and documentation and convened a project kick-off meeting with Industry Advisors in attendance (see Black and Judzis); (2) TerraTek designed and planned Phase I bench scale experiments (See Black and Judzis). Improvements were made to the loading mechanism and the rotational speed monitoring instrumentation. New drill bit designs were developed to provided a more consistent product with consistent performance. A test matrix for the final core bit testing program was completed; (3) TerraTek concluded small-scale cutting performance tests; (4) Analysis of Phase 1 data indicated that there is decreased specific energy as the rotational speed increases; (5) Technology transfer, as part of Phase 1, was accomplished with technical presentations to the industry (see Judzis, Boucher, McCammon, and Black); (6) TerraTek prepared a design concept for the high speed drilling test stand, which was planned around the proposed high speed mud motor concept. Alternative drives for the test stand were explored; a high speed hydraulic motor concept was finally used; (7) The high speed system was modified to accommodate larger drill bits than originally planned; (8) Prototype mud turbine motors and the high speed test stand were used to drive the drill bits at high speed; (9) Three different rock types were used during the testing: Sierra White granite, Crab Orchard sandstone, and Colton sandstone. The drill bits used included diamond impregnated bits, a polycrystalline diamond compact (PDC) bit, a thermally stable PDC (TSP) bit, and a hybrid TSP and natural diamond bit; and (10) The drill bits were run at rotary speeds up to 5500 rpm and weight on bit (WOB) to 8000 lbf. During Phase 2, the ROP as measured in depth of cut per bit revolution generally increased with increased WOB. The performance was mixed with increased rotary speed, with the depth cut with the impregnated drill bit generally increasing and the TSP and hybrid TSP drill bits generally decreasing. The ROP in ft/hr generally increased with all bits with increased WOB and rotary speed. The mechanical specific energy generally improved (decreased) with increased WOB and was mixed with increased rotary speed.

TerraTek, A Schlumberger Company

2008-12-31T23:59:59.000Z

146

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

147

Demonstration and Performance Monitoring of Foundation Heat Exchangers (FHX) in Ultra-High Energy Efficient Research Homes  

SciTech Connect (OSTI)

The more widespread use of Ground Source Heat Pump (GSHP) systems has been hindered by their high first cost, which is mainly driven by the cost of the drilling and excavation for installation of ground heat exchangers (GHXs). A new foundation heat exchanger (FHX) technology was proposed to reduce first cost by placing the heat exchanger into the excavations made during the course of construction (e.g., the overcut for the basement and/or foundation and run-outs for water supply and the septic field). Since they reduce or eliminate the need for additional drilling or excavation, foundation heat exchangers have the potential to significantly reduce or eliminate the first cost premium associated with GSHPs. Since December 2009, this FHX technology has been demonstrated in two ultra-high energy efficient new research houses in the Tennessee Valley, and the performance data has been closely monitored as well. This paper introduces the FHX technology with the design, construction and demonstration of the FHX and presents performance monitoring results of the FHX after one year of monitoring. The performance monitoring includes hourly maximum and minimum entering water temperature (EWT) in the FHX compared with the typical design range, temperature difference (i.e., T) across the FHX, and hourly heat transfer rate to/from the surrounding soil.

Im, Piljae [ORNL] [ORNL; Hughes, Patrick [ORNL] [ORNL; Liu, Xiaobing [ORNL] [ORNL

2012-01-01T23:59:59.000Z

148

Ultra-high energy cosmic rays, cascade gamma-rays, and high-energy neutrinos from gamma-ray bursts  

E-Print Network [OSTI]

Gamma-ray bursts (GRBs) are sources of energetic, highly variable fluxes of gamma rays, which demonstrates that they are powerful particle accelerators. Besides relativistic electrons, GRBs should also accelerate high-energy hadrons, some of which could escape cooling to produce ultra-high energy cosmic rays (UHECRs). Acceleration of high-energy hadrons in GRB blast waves will be established if high-energy neutrinos produced through photopion interactions in the blast wave are detected from GRBs. Limitations on the energy in nonthermal hadrons and the number of expected neutrinos are imposed by the fluxes from pair-photon cascades initiated in the same processes that produce neutrinos. Only the most powerful bursts at fluence levels >~ 3e-4 erg/cm^2 offer a realistic prospect for detection of >> TeV neutrinos. Detection of high-energy neutrinos is likely if GRB blast waves have large baryon loads and Doppler factors <~ 200. Cascade gamma rays will accompany neutrino production and might already have been detected as anomalous emission components in the spectra of some GRBs. Prospects for detection of GRBs in the Milky Way are also considered.

Charles D. Dermer; Armen Atoyan

2006-06-26T23:59:59.000Z

149

Anomalies in Ultra-High-Field Magnetic Superconductors (Eu1-xSnx)Mo6S8  

Science Journals Connector (OSTI)

Resistive behavior of three series of Chevrel phase, (Eu1-xSnx)Mo6S7, (Eu1-xSnx)Mo6S6.75 and (Eu1-xSnx)0.9Mo6S6.75, is studied in magnetic fields up to 90 kOe at temperatures down to 50 mK. Compounds with x>0.4 are usual ultra-high-field superconductors, while (Eu0.9Sn0.1)0.9Mo6S6.75 is a simple magnetic superconductor. Resistive behavior of the compounds between the above mentioned two sides is complicated, varying with the composition. For example, in (Eu0.8Sn0.2)Mo6S7 the resistance at high fields keeps roughly constant and the temperature dependence of Hc2 defined as a half of the resistance in the normal state is quite different with that defined at the appearance of the resistance. In (Eu0.85Sn0.15)Mo6S7 the superconductivity (=zero resistance) seems to reappear at high fields and at low temperatures.

Masahiro Isino; Norio Kobayashi; Yoshio Muto

1980-01-01T23:59:59.000Z

150

Performance analysis of AlGaAs/GaAs tunnel junctions for ultra-high concentration photovoltaics  

Science Journals Connector (OSTI)

An n++-GaAs/p++-AlGaAs tunnel junction with a peak current density of 10?100Acm?2 is developed. This device is a tunnel junction for multijunction solar cells, grown lattice-matched on standard GaAs or Ge substrates, with the highest peak current density ever reported. The voltage drop for a current density equivalent to the operation of the multijunction solar cell up to 10?000suns is below 5mV. Trap-assisted tunnelling is proposed to be behind this performance, which cannot be justified by simple band-to-band tunnelling. The metal-organic vapour-phase epitaxy growth conditions, which are in the limits of the transport-limited regime, and the heavy tellurium doping levels are the proposed origins of the defects enabling trap-assisted tunnelling. The hypothesis of trap-assisted tunnelling is supported by the observed annealing behaviour of the tunnel junctions, which cannot be explained in terms of dopant diffusion or passivation. For the integration of these tunnel junctions into a triple-junction solar cell, AlGaAs barrier layers are introduced to suppress the formation of parasitic junctions, but this is found to significantly degrade the performance of the tunnel junctions. However, the annealed tunnel junctions with barrier layers still exhibit a peak current density higher than 2500Acm?2 and a voltage drop at 10?000suns of around 20mV, which are excellent properties for tunnel junctions and mean they can serve as low-loss interconnections in multijunction solar cells working at ultra-high concentrations.

I Garca; I Rey-Stolle; C Algora

2012-01-01T23:59:59.000Z

151

Ultra High Energy Cosmic Rays, Z-Shower and Neutrino Astronomy by Horizontal-Upward Tau Air-Showers  

E-Print Network [OSTI]

Ultra High Cosmic Rays (UHECR) Astronomy may be correlated to a primary parental Neutrino Astronomy: indeed any far BL Lac Jet or GRB, sources of UHECR, located at cosmic edges, may send its signal, overcoming the severe GZK cut-off, by help of UHE ZeV energetic neutrino primary. These UHE neutrino scattering on relic light ones (spread on wide Hot Local Groups Halos) maybe fine-tuned : E_(nu) =(M_Z)^2/m_(nu) = 4 10^(22) eV *((0.1eV)/m_(nu)), to combine at once the observed light neutrino masses and the UHECR spectra, leading to a relativistic Z-Shower in Hot Dark Halos (e few tens Mpc wide) whose final nuclear component traces the UHECR event on Earth. Therefore UHECR (with no longer volme GZK constrains) may point to far BL Lac sources. This Z-Burst (Z-Shower) model calls for large neutrino fluxes. Even if Nature do not follow the present Z-model, UHECR while being cut-off by Big Bang Radiation, must produce a minimal UHE neutrino flux, the GZK neutrino secondaries. For both reasons such UHE Neutrino Astronomy must be tested on Earth. Lowest High Energy Astronomy is searched by AMANDA, ANTARES underground deterctors by muons tracks. We suggest a complementary higher energy Neutrino Tau Astronomy inducing Horizontal and Upward Tau AirShowers. Possible early evidence of such a New Neutrino UPTAUs (Upward Tau Showers at PeVs energies) Astronomy may be in BATSE records of Upward Terrestrial Gamma Flashes. Future signals must be found in detectors as EUSO, seeking Upward-Horizontal events: indeed even minimal, guaranteed, GZK neutrino fluxes may be better observed if EUSO threshold reaches 10^(19) eV by enlarging its telescope size.

D. Fargion

2003-06-24T23:59:59.000Z

152

Comparison of high and low intensity contact between secondary and primary care to detect people at ultra-high risk for psychosis: study protocol for a theory-based, cluster randomized controlled trial  

E-Print Network [OSTI]

Abstract Background The early detection and referral to specialized services of young people at ultra-high risk (UHR) for psychosis may reduce the duration of untreated psychosis and, therefore, improve prognosis. General practitioners (GPs...

Perez, Jesus; Russo, Debra A; Stochl, Jan; Byford, Sarah; Zimbron, Jorge; Graffy, Jonathan P; Painter, Michelle; Croudace, Tim J; Jones, Peter B

2013-07-17T23:59:59.000Z

153

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

154

Thermal properties of La2O3-doped ZrB2- and HfB2-based ultra-high temperature ceramics  

Science Journals Connector (OSTI)

Abstract Thermal properties of La2O3-doped ZrB2- and HfB2-based ultra high temperature ceramics (UHTCs) have been measured at temperatures from room temperature to 2000C and compared with SiC-doped ZrB2- and HfB2-based \\{UHTCs\\} and monolithic ZrB2 and HfB2. Thermal conductivities of La2O3-doped \\{UHTCs\\} remain constant around 5560W/mK from 1500C to 1900C while SiC-doped \\{UHTCs\\} showed a trend to decreasing values over this range.

E. Zapata-Solvas; D.D. Jayaseelan; P.M. Brown; W.E. Lee

2013-01-01T23:59:59.000Z

155

PV Conversion Technologies, Session: OPV, Sensitized, Seed (Presentation)  

SciTech Connect (OSTI)

The NREL Sensitized Solar Cell (SSC) Core Program supports the Solar America Initiative by: (1) targeting new devices and processes for commercialization by 2015 that are less expensive, more efficient, highly reliable, and environmentally benign; (2) collaborating with DOE OS/BES to conduct basic research targeting breakthroughs in key areas, such as ultra-high efficiency and/or ultra-low cost materials and devices.

Frank, A. J.

2008-04-01T23:59:59.000Z

156

Atomic and molecular interstellar absorption lines toward the high galactic latitude stars HD~141569 and HD~157841 at ultra-high resolution  

E-Print Network [OSTI]

We present ultra-high resolution (0.32 km/s) spectra obtained with the 3.9m Anglo-Australian Telescope (AAT) and Ultra-High-Resolution Facility (UHRF), of interstellar NaI D1, D2, Ca II K, K I and CH absorption toward two high galactic latitude stars HD141569 and HD157841. We have compared our data with 21-cm observations obtained from the Leiden/Dwingeloo HI survey. We derive the velocity structure, column densities of the clouds represented by the various components and identify the clouds with ISM structures seen in the region at other wavelengths. We further derive abundances, linear depletions and H2 fractional abundances for these clouds, wherever possible. Toward HD141569, we detect two components in our UHRF spectra : a weak, broad component at - 15 km/s, seen only in CaII K absorption and another component at 0 km/s, seen in NaI D1, D2, Ca II K, KI and CH absorption. In the case of the HD157841 sightline, a total of 6 components are seen on our UHRF spectra in NaI D1, D2 Ca II K, K I and CH absorption. 2 of these 6 components are seen only in a single species.

M. S. Sahu; J. C. Blades; L. He; D. Hartmann; M. J. Barlow; I. A. Crawford

1998-03-31T23:59:59.000Z

157

ARM - Measurement - Aerosol absorption  

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

158

ARM - Measurement - Aerosol concentration  

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

159

Carbonaceous Aerosols and Radiative...  

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

160

Atmospheric aerosol monitoring at the Pierre Auger Observatory  

SciTech Connect (OSTI)

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

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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

BNL | Aerosol Lifecycle IOP  

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

162

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

163

ARM - Measurement - Aerosol particle size  

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

164

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

165

Polarization-dependent all-optical modulator with ultra-high modulation depth based on a stereo graphene-microfiber structure  

E-Print Network [OSTI]

We report an in-line polarization-dependent all-optical fiber modulator based on a stereo graphene-microfiber structure (GMF) by utilizing the lab-on-rod technique. Owing to the unique spring-like geometry, an ultra-long GMF interaction length can be achieved, and an ultra-high modulation depth (MD) of ~7.5 dB and a high modulation efficiency (ME) of ~0.2 dB/mW were demonstrated for one polarization state. The MD and ME are more than one order larger than those of other graphene-waveguide hybrid all-optical modulators. By further optimizing the transferring and cleaning process, the modulator can quickly switch between transparent and opaque states for both the two polarization states with a maximized MD of tens of decibels. This modulator is compatible with current fiber-optic communication systems and may be applied in the near future to meet the impending need for ultrafast optical signal processing.

Xu, Fei; Zheng, Bi-cai; Shao, Guang-hao; Ge, Shi-jun; Lu, Yan-qing

2015-01-01T23:59:59.000Z

166

Super-Penrose collisions are inefficient - a Comment on: Black hole fireworks: ultra-high-energy debris from super-Penrose collisions  

E-Print Network [OSTI]

In a paper posted on the arXiv a few weeks ago Berti, Brito and Cardoso \\cite{Berti+14} suggest that ultra-high-energy particles can emerge from collisions in a black hole's ergosphere. This can happen if the process involves a particle on an outgoing trajectory very close to the black hole. Clearly such a particle cannot emerge from the black hole. It is argued \\cite{Berti+14} that this particle can arise in another collision. Thus the process involves two collisions: one in which an outgoing particle is produced extremely close to the horizon, and a second one in which energy is gained. The real efficiency of this process should take into account, therefore, the energy needed to produce the first particle. We show here that while this process is kinematically possible, it requires a deposition of energy that is divergently large compared with the energy of the escaping particle. Thus, in contradiction to claims of infinitely high efficiencies, the efficiency of the combined process is in fact extremely smal...

Leiderschneider, Elly

2015-01-01T23:59:59.000Z

167

CORRELATIONS OF THE ARRIVAL DIRECTIONS OF ULTRA-HIGH ENERGY COSMIC RAYS WITH EXTRAGALACTIC OBJECTS AS OBSERVED BY THE TELESCOPE ARRAY EXPERIMENT  

SciTech Connect (OSTI)

We search for correlations between the positions of extragalactic objects and the arrival directions of ultra-high energy cosmic rays (UHECRs) with primary energy E ? 40 EeV as observed by the surface detector array of the Telescope Array (TA) experiment during the first 40 months of operation. We examine several public astronomical object catalogs, including the Veron-Cetty and Veron catalog of active galactic nuclei. We count the number of TA events correlated with objects in each catalog as a function of three parameters: the maximum angular separation between a TA event and an object, the minimum energy of the events, and the maximum redshift of the objects. We determine the combination of these parameters that maximizes the correlations, and we calculate the probability of having the same levels of correlations from an isotropic distribution of UHECR arrival directions. No statistically significant correlations are found when penalties for scanning over the above parameters and for searching in several catalogs are taken into account.

Abu-Zayyad, T.; Allen, M.; Anderson, R.; Barcikowski, E.; Belz, J. W.; Bergman, D. R.; Blake, S. A.; Cady, R.; Hanlon, W. [High Energy Astrophysics Institute and Department of Physics and Astronomy, University of Utah, Salt Lake City, UT (United States); Aida, R. [Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Kofu, Yamanashi (Japan); Azuma, R.; Fukuda, T. [Graduate School of Science and Engineering, Tokyo Institute of Technology, Meguro, Tokyo (Japan); Cheon, B. G.; Cho, E. J. [Department of Physics and The Research Institute of Natural Science, Hanyang University, Seongdong-gu, Seoul (Korea, Republic of); Chiba, J. [Department of Physics, Tokyo University of Science, Noda, Chiba (Japan); Chikawa, M. [Department of Physics, Kinki University, Higashi Osaka, Osaka (Japan); Cho, W. R. [Department of Physics, Yonsei University, Seodaemun-gu, Seoul (Korea, Republic of); Fujii, H. [Institute of Particle and Nuclear Studies, KEK, Tsukuba, Ibaraki (Japan); Fujii, T. [Graduate School of Science, Osaka City University, Osaka (Japan); Fukushima, M. [Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba (Japan); and others

2013-11-10T23:59:59.000Z

168

The PLATO End-to-End CCD Simulator -- Modelling space-based ultra-high precision CCD photometry for the assessment study of the PLATO Mission  

E-Print Network [OSTI]

The PLATO satellite mission project is a next generation ESA Cosmic Vision satellite project dedicated to the detection of exo-planets and to asteroseismology of their host-stars using ultra-high precision photometry. The main goal of the PLATO mission is to provide a full statistical analysis of exo-planetary systems around stars that are bright and close enough for detailed follow-up studies. Many aspects concerning the design trade-off of a space-based instrument and its performance can best be tackled through realistic simulations of the expected observations. The complex interplay of various noise sources in the course of the observations made such simulations an indispensable part of the assessment study of the PLATO Payload Consortium. We created an end-to-end CCD simulation software-tool, dubbed PLATOSim, which simulates photometric time-series of CCD images by including realistic models of the CCD and its electronics, the telescope optics, the stellar field, the pointing uncertainty of the satellite ...

Zima, W; De Ridder, J; Salmon, S; Catala, C; Kjeldsen, H; Aerts, C

2010-01-01T23:59:59.000Z

169

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

SciTech Connect (OSTI)

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

Kmetyk, L.N.

1991-09-01T23:59:59.000Z

170

Atmospheric aerosols and possibilities of their analysis for elemental content at the IBR-2 reactor  

Science Journals Connector (OSTI)

Possibilities of neutron activation analysis for studying the elemental content of atmospheric aerosols at the IBR-2 reactor are discussed on the bases of the ... contents on the sensitivity of NAA, the reliability

V. F. Peresedov

1997-10-01T23:59:59.000Z

171

Ultra High Energy Cosmic Rays  

Science Journals Connector (OSTI)

......tral data at energies above 1 EeV (1018eV...from the AGASA project, are very suggestive...since these low energy cosmic rays have...the outflowing solar wind plasma and...it does on the energy limit set by the solar wind. Since there......

Roger Clay

2003-05-01T23:59:59.000Z

172

Geometrical Optics of Dense Aerosols  

SciTech Connect (OSTI)

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

173

BNL | Aerosol, Cloud, Precipitation Interactions  

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

174

Jankovic Aerosol Characterization.ppt  

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

175

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

176

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

SciTech Connect (OSTI)

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

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

1994-10-01T23:59:59.000Z

177

Aerosols in a Changing Atmosphere: From Detailed Aerosol Microphysics to  

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

178

ARM - Mobile Aerosol Observing System  

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

179

Aerosol Observing System (AOS) Handbook  

SciTech Connect (OSTI)

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 earths 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

180

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

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


181

EMSL: Science: Atmospheric Aerosol Systems  

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

182

Two-Column Aerosol Project  

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

183

ARM Cloud Aerosol Precipitation Experiment  

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

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

184

Molecular Characterization of Biomass Burning Aerosols Using...  

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

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

185

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

186

Predicted change in global secondary organic aerosol concentrations in response to future climate, emissions, and land use change  

E-Print Network [OSTI]

The sensitivity of secondary organic aerosol (SOA) concentration to changes in climate and emissions is investigated using a coupled global atmosphere-land model driven by the year 2100 IPCC A1B scenario predictions. The ...

Heald, C. L.; Henze, D. K.; Horowitz, L. W.; Feddema, Johannes J.; Lamarque, J. F.; Guenther, A.; Hess, P. G.; Vitt, F.; Seinfeld, J. H.; Goldstein, A. H.; Fung, I.

2008-03-01T23:59:59.000Z

187

Aerosol Laboratory - Nuclear Engineering Division (Argonne)  

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

188

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

SciTech Connect (OSTI)

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

189

Sensitive Species  

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

Sensitive Species Sensitive Species Sensitive Species By avoiding or minimizing the impact of Laboratory activities on sensitive species, LANL can potentially reduce the possibility of these species being upgraded to federal protection. April 12, 2012 sensitive species The bald eagle is one of our sensitive species. Contact Environmental Communication & Public Involvement P.O. Box 1663 MS M996 Los Alamos, NM 87545 (505) 667-0216 Email Sensitive species are plants and animals that are protected at the state or local level. Keeping sensitive species safe We strive to minimize the impact of Laboratory operations on sensitive species, which are plants and animals not protected by the federal Endangered Species Act or the Migratory Bird Treaty Act, but are protected on state or local levels.

190

ARM - Surface Aerosol Observing System  

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

191

Global Distribution and Climate Forcing of Marine Organic Aerosol - Part 2: Effects on Cloud Properties and Radiative Forcing  

SciTech Connect (OSTI)

A series of simulations with the Community Atmosphere Model version 5 (CAM5) with a 7-mode Modal Aerosol Model were conducted to assess the changes in cloud microphysical properties and radiative forcing resulting from marine organic aerosols. Model simulations show that the anthropogenic aerosol indirect forcing (AIF) predicted by CAM5 is decreased in absolute magnitude by up to 0.09 Wm{sup -2} (7 %) when marine organic aerosols are included. Changes in the AIF from marine organic aerosols are associated with small global increases in low-level incloud droplet number concentration and liquid water path of 1.3 cm{sup -3} (1.5 %) and 0.22 gm{sup -2} (0.5 %), respectively. Areas especially sensitive to changes in cloud properties due to marine organic aerosol include the Southern Ocean, North Pacific Ocean, and North Atlantic Ocean, all of which are characterized by high marine organic emission rates. As climate models are particularly sensitive to the background aerosol concentration, this small but non-negligible change in the AIF due to marine organic aerosols provides a notable link for ocean-ecosystem marine low-level cloud interactions and may be a candidate for consideration in future earth system models.

Gantt, Brett; Xu, Jun; Meskhidze, N.; Zhang, Yang; Nenes, Athanasios; Ghan, Steven J.; Liu, Xiaohong; Easter, Richard C.; Zaveri, Rahul A.

2012-07-25T23:59:59.000Z

192

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

SciTech Connect (OSTI)

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

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

2014-09-23T23:59:59.000Z

193

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

194

ARM - Evaluation Product - Organic Aerosol Component VAP  

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

195

ARM - Field Campaign - Fall 1997 Aerosol IOP  

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

196

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

197

Antiviral therapy with small particle aerosols  

Science Journals Connector (OSTI)

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

V. Knight; B. Gilbert

1988-12-01T23:59:59.000Z

198

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

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

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

199

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

200

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

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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

ARM - Measurement - Aerosol optical depth  

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

202

ARM - Measurement - Aerosol optical properties  

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

203

ARM - Measurement - Aerosol backscattered radiation  

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

204

Versatile, high-sensitivity faraday cup array for ion implanters  

DOE Patents [OSTI]

An improved Faraday cup array for determining the dose of ions delivered to a substrate during ion implantation and for monitoring the uniformity of the dose delivered to the substrate. The improved Faraday cup array incorporates a variable size ion beam aperture by changing only an insertable plate that defines the aperture without changing the position of the Faraday cups which are positioned for the operation of the largest ion beam aperture. The design enables the dose sensitivity range, typically 10.sup.11 -10.sup.18 ions/cm.sup.2 to be extended to below 10.sup.6 ions/cm.sup.2. The insertable plate/aperture arrangement is structurally simple and enables scaling to aperture areas between <1 cm.sup.2 and >750 cm.sup.2, and enables ultra-high vacuum (UHV) applications by incorporation of UHV-compatible materials.

Musket, Ronald G. (Danville, CA); Patterson, Robert G. (Dublin, CA)

2003-01-01T23:59:59.000Z

205

Observations of the first aerosol indirect effect in shallow cumuli  

SciTech Connect (OSTI)

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

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

2011-02-08T23:59:59.000Z

206

Review of models applicable to accident aerosols  

SciTech Connect (OSTI)

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

Glissmeyer, J.A.

1983-07-01T23:59:59.000Z

207

Ultra-high CO2 capture efficiency in CFB oxyfuel power plants by calcium looping process for CO2 recovery from purification units vent gas  

Science Journals Connector (OSTI)

Abstract This work presents a new option for the recovery of the CO2 losses from CO2 purification units in oxyfuel plants, by means of the Ca-looping process. The idea is to capture the CO2 in the vent stream from purification units by reaction with CaO sorbent in a carbonator reactor, where CaCO3 is formed. Sorbent is then regenerated in a calciner reactor by oxyfuel combustion of a fraction of the coal fed to the power plant. Since the Ca-looping process requires a continuous purge of exhaust sorbent and make-up of fresh limestone, the system is best coupled with a CFB boiler, where the exhausted Ca-rich sorbent can be used for in-furnace sulfur absorption. In this work, detailed mass and energy balances of the system proposed are reported, including a preliminary sizing of the reactors of the Ca-looping unit. A sensitivity analysis was also performed, by considering two types of coal as feed (mainly differing in sulfur content), two levels of non-condensable gases in the impure CO2 stream to be purified and different behaviors of the exhausted Ca-based sorbent injected in the CFB boiler, where it can experience different levels of recarbonation. Interesting results were obtained for this new system, which can capture about 90% of the CO2 vented from the purification unit in a reasonably compact reactors system, allowing an overall CO2 avoidance of the order of 99% with respect to conventional coal-fired steam plants without capture. As far as energy penalties are concerned, they were evaluated by the specific primary energy consumption for CO2 avoided index (SPECCA). Small differences with respect to reference oxyfuel plants without CO2 recovery were obtained, with either slightly better or slightly worse performances, depending on the sulfur content of the coal used. Penalties are associated to the export of CaO in the final exhausted sulfated sorbent from the CFB boiler, which increases when a higher sulfur coal is used. However, experimental analysis on the recarbonation level which can be attained by the CaL exhaust sorbent in the CFB boiler and further process optimization are needed to correctly account for these penalties and possibly minimize them.

Matteo C. Romano

2013-01-01T23:59:59.000Z

208

Sensitive Species  

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

plants and animals not protected by the federal Endangered Species Act or the Migratory Bird Treaty Act, but are protected on state or local levels. The Sensitive Species Best...

209

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

SciTech Connect (OSTI)

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

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

2014-01-29T23:59:59.000Z

210

Study of cavity type antenna structure of large-area 915 MHz ultra-high frequency wave plasma device based on three-dimensional finite difference time-domain analysis  

SciTech Connect (OSTI)

A large-area planar plasma source with a resonant cavity type launcher driven by a 915 MHz ultra-high frequency wave was developed. Theoretical analysis with the three-dimensional finite difference time-domain simulation was carried out to determine the optimized launcher structure by analyzing the resonant transverse magnetic mode in the resonant cavity. Numerical result expects that the resonant electric field distribution inside the cavity dominantly consists of the TM{sub 410} mode. The resonant cavity type launcher having 8 holes in an octagonal geometry was designed to fit the resonant transverse magnetic mode. Adjusting 8 hole positions of the launcher to the field pattern of the resonant TM{sub 410} mode, we found that the plasma density increased about 40%?50% from 1.0?1.1 10{sup 11} cm{sup ?3} to ?1.5 10{sup 11} cm{sup ?3} at the same incident power of 2.5 kW, compared with the previous results with the launcher having 6 holes in the hexagonal geometry. It is also noted that the electron density changes almost linearly with the incident wave power without any mode jumps.

Chang, Xijiang [Department of Light Sources and Illuminating Engineering, Fudan University, 220 Handan Road, Shanghai 200433 (China) [Department of Light Sources and Illuminating Engineering, Fudan University, 220 Handan Road, Shanghai 200433 (China); Graduate School of Science and Engineering, Shizuoka University, 3-5-1 Johoku, Hamamatsu 432-8561 (Japan); Kunii, Kazuki [Graduate School of Engineering, Shizuoka University,3-5-1 Johoku, Hamamatsu 432-8561 (Japan)] [Graduate School of Engineering, Shizuoka University,3-5-1 Johoku, Hamamatsu 432-8561 (Japan); Liang, Rongqing [Department of Light Sources and Illuminating Engineering, Fudan University, 220 Handan Road, Shanghai 200433 (China)] [Department of Light Sources and Illuminating Engineering, Fudan University, 220 Handan Road, Shanghai 200433 (China); Nagatsu, Masaaki [Graduate School of Science and Engineering, Shizuoka University, 3-5-1 Johoku, Hamamatsu 432-8561 (Japan) [Graduate School of Science and Engineering, Shizuoka University, 3-5-1 Johoku, Hamamatsu 432-8561 (Japan); Graduate School of Engineering, Shizuoka University,3-5-1 Johoku, Hamamatsu 432-8561 (Japan)

2013-11-14T23:59:59.000Z

211

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

212

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

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

213

Improving Bulk Microphysics Parameterizations in Simulations of Aerosol Effects  

SciTech Connect (OSTI)

To improve the microphysical parameterizations for simulations of the aerosol indirect effect (AIE) in regional and global climate models, a double-moment bulk microphysical scheme presently implemented in the Weather Research and Forecasting (WRF) model is modified and the results are compared against atmospheric observations and simulations produced by a spectral bin microphysical scheme (SBM). Rather than using prescribed aerosols as in the original bulk scheme (Bulk-OR), a prognostic doublemoment aerosol representation is introduced to predict both the aerosol number concentration and mass mixing ratio (Bulk-2M). The impacts of the parameterizations of diffusional growth and autoconversion and the selection of the embryonic raindrop radius on the performance of the bulk microphysical scheme are also evaluated. Sensitivity modeling experiments are performed for two distinct cloud regimes, maritime warm stratocumulus clouds (SC) over southeast Pacific Ocean from the VOCALS project and continental deep convective clouds (DCC) in the southeast of China from the Department of Energy/ARM Mobile Facility (DOE/AMF) - China field campaign. The results from Bulk-2M exhibit a much better agreement in the cloud number concentration and effective droplet radius in both the SC and DCC cases with those from SBM and field measurements than those from Bulk-OR. In the SC case particularly, Bulk-2M reproduces the observed drizzle precipitation, which is largely inhibited in Bulk-OR. Bulk-2M predicts enhanced precipitation and invigorated convection with increased aerosol loading in the DCC case, consistent with the SBM simulation, while Bulk-OR predicts the opposite behaviors. Sensitivity experiments using four different types of autoconversion schemes reveal that the autoconversion parameterization is crucial in determining the raindrop number, mass concentration, and drizzle formation for warm 2 stratocumulus clouds. An embryonic raindrop size of 40 ?m is determined as a more realistic setting in the autoconversion parameterization. The saturation adjustment employed in calculating condensation/evaporation in the bulk scheme is identified as the main factor responsible for the large discrepancies in predicting cloud water in the SC case, suggesting that an explicit calculation of diffusion growth with predicted supersaturation is necessary for further improvements of the bulk microphysics scheme. Lastly, a larger rain evaporation rate below cloud is found in the bulk scheme in comparison to the SBM simulation, which could contribute to a lower surface precipitation in the bulk scheme.

Wang, Yuan; Fan, Jiwen; Zhang, Renyi; Leung, Lai-Yung R.; Franklin, Charmaine N.

2013-06-05T23:59:59.000Z

214

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

215

Separating Cloud Forming Nuclei from Interstitial Aerosol  

SciTech Connect (OSTI)

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

Kulkarni, Gourihar R.

2012-09-12T23:59:59.000Z

216

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

217

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

SciTech Connect (OSTI)

This project examined the potential large-scale influence of marine aerosol cycling on atmospheric chemistry, physics and radiative transfer. Measurements indicate that the size-dependent generation of marine aerosols by wind waves at the ocean surface and the subsequent production and cycling of halogen-radicals are important but poorly constrained processes that influence climate regionally and globally. A reliable capacity to examine the role of marine aerosol in the global-scale atmospheric system requires that the important size-resolved chemical processes be treated explicitly. But the treatment of multiphase chemistry across the breadth of chemical scenarios encountered throughout the atmosphere is sensitive to the initial conditions and the precision of the solution method. This study examined this sensitivity, constrained it using high-resolution laboratory and field measurements, and deployed it in a coupled chemical-microphysical 3-D atmosphere model. First, laboratory measurements of fresh, unreacted marine aerosol were used to formulate a sea-state based marine aerosol source parameterization that captured the initial organic, inorganic, and physical conditions of the aerosol population. Second, a multiphase chemical mechanism, solved using the Max Planck Institute for Chemistry??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 Earth??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

218

Comparative Analysis of Urban Atmospheric Aerosol by Particle...  

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

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

219

The Two-Column Aerosol Project Definitions TCAP Educational  

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

220

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

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

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

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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

The Indirect and Semi-Direct Aerosol Campaign  

SciTech Connect (OSTI)

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

Ghan, Steve

2014-03-24T23:59:59.000Z

222

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

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

223

Molecular Chemistry of Organic Aerosols Through the Application...  

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

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

224

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

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

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

225

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

SciTech Connect (OSTI)

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

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

2013-07-16T23:59:59.000Z

226

BNL | Mobile Aerosol Observing System (MAOS)  

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

227

The Opposed Migration Aerosol Classifier (OMAC)  

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

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

228

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

SciTech Connect (OSTI)

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

Phillips, Vaughan T. J.

2013-10-18T23:59:59.000Z

229

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

230

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

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

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

231

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

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

232

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

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

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

233

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

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

234

BUSINESS SENSITIVE  

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

Chairman, Subcommittee on Energy Chairman, Subcommittee on Energy and Water Development and Water Development Committee on Appropriations Committee on Appropriations U.S. House of Representatives U.S. Senate Washington, DC 20515 Washington, DC 20510 Subject: Section 311 Notification of Pending Public Announcement of Selection of Applications for Negotiation of Financial Assistance Awards Dear Chairmen Rogers, Inouye, Frelinghuysen and Feinstein: In accordance with Section 311 of P.L. 111-85, no earlier than three full business days from the date of this notification, the Department of Energy intends to announce publicly one or more selections for negotiation of financial assistance award(s) over $1,000,000. This information is market sensitive, predecisional and not public at this time. Accordingly,

235

BUSINESS SENSITIVE  

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

Chairman, Subcommittee on Energy Chairman, Subcommittee on Energy and Water Development and Water Development Committee on Appropriations Committee on Appropriations U.S. House of Representatives U.S. Senate Washington, DC 20515 Washington, DC 20510 Subject: Section 311 Notification to Make a Non-competitive Financial Assistance Award Dear Chairmen Rogers, Inouye, Frelinghuysen and Feinstein: No earlier than three full business days from the date of this notification, the Department of Energy intends to award an action over $1,000,000 in accordance with Section 311 of P.L. 111-85. This information is market sensitive, predecisional and not public at this time. Accordingly, we request that you do not further disseminate this information. If you are considering

236

CARES: Carbonaceous Aerosol and Radiative Effects Study Science Plan  

SciTech Connect (OSTI)

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

Zaveri, RA; Shaw, WJ; Cziczo, DJ

2010-05-27T23:59:59.000Z

237

Capstone Depleted Uranium Aerosols: Generation and Characterization  

SciTech Connect (OSTI)

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

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

2004-10-19T23:59:59.000Z

238

Southern hemisphere tropospheric aerosol microphysics  

SciTech Connect (OSTI)

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

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

1991-03-20T23:59:59.000Z

239

Composition and Reactions of Atmospheric Aerosol Particles  

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

240

Composition and Reactions of Atmospheric Aerosol Particles  

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

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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

BNL | Two-Column Aerosol Program (TCAP)  

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

242

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

Science Journals Connector (OSTI)

Plans for NASAs 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

243

Aerosol Best Estimate Value-Added Product  

SciTech Connect (OSTI)

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

244

Composition and Reactions of Atmospheric Aerosol Particles  

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

245

ARM - Field Campaign - Aerosol Life Cycle IOP at BNL  

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

246

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

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

247

DETERMINATION OF RADIAL MOMENTS OF AN AEROSOL  

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

248

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

249

Electrically Driven Technologies for Radioactive Aerosol Abatement  

SciTech Connect (OSTI)

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

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

2003-01-28T23:59:59.000Z

250

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

251

Atmospheric Aerosol Chemistry Analyzer: Demonstration of feasibility  

SciTech Connect (OSTI)

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

252

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

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

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

253

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

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

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

254

Clouds of short-circuited thermionic nanobatteries and promising prospects for development of nanobattery-based aerosol fusion reactors. The preliminary report  

E-Print Network [OSTI]

The physical mechanisms of periodic separation and relaxation of electric charges within aerosol particles possessing the properties the short-circuited batteries can be extremely diverse. With use of appropriate materials and dispersing methods, the electrochemical, thermoelectric, thermionic, pyroelectric, photoelectric, photo electronic emission, or even radionuclide-based emission micro and nano-batteries can be synthesized and be dispersed in the air as clouds self-assembed of the short-circuited aerosol batteries due to the inter-particle electromagnetic dipole-dipole attraction. Intense thermionic emission from ionized hot spots migrating on the relatively cold surface of charged explosive particles, can convert these particles into short-circuited thermionic batteries, turning an aerosol cloud consisting of such unipolar charged, gradually decomposing explosive particles into ball lightning. The slow exothermic decomposition of the highly sensitive explosive aerosol particles, catalyzed by excess ions on their surface, and also ion-catalyzed reactions of slow water vapor induced oxidation of charged combustible aerosol particles underlie two main classes of natural ball lightning. At the same time, the artificially generated clouds consisting of such unipolar charged aerosol nanobatteries, probably, can have some useful applications, not only military ones. In particular, it seems that high-performance pyroelectric fusion reactors could be created on the basis of such ball-shaped aerosol clouds self-assembled of pyroelectric nanocrystals - short-circuited pyroelectric nanobatteries.

Oleg Meshcheryakov

2012-04-13T23:59:59.000Z

255

Linearity of Climate Response to Increases in Black Carbon Aerosols  

SciTech Connect (OSTI)

The impact of absorbing aerosols on global climate are not completely understood. Here, we present results of idealized experiments conducted with the Community Atmosphere Model (CAM4) coupled to a slab ocean model (CAM4-SOM) to simulate the climate response to increases in tropospheric black carbon aerosols (BC) by direct and semi-direct effects. CAM4-SOM was forced with 0, 1x, 2x, 5x and 10x an estimate of the present day concentration of BC while maintaining their estimated present day global spatial and vertical distribution. The top of the atmosphere (TOA) radiative forcing of BC in these experiments is positive (warming) and increases linearly as the BC burden increases. The total semi-direct effect for the 1x experiment is positive but becomes increasingly negative for higher BC concentrations. The global average surface temperature response is found to be a linear function of the TOA radiative forcing. The climate sensitivity to BC from these experiments is estimated to be 0.42 K $\\textnormal W^{-1} m^{2}$ when the semi-direct effects are accounted for and 0.22 K $\\textnormal W^{-1} m^{2}$ with only the direct effects considered. Global average precipitation decreases linearly as BC increases, with a precipitation sensitivity to atmospheric absorption of 0.4 $\\%$ $\\textnormal W^{-1} \\textnormal m^{2}$ . The hemispheric asymmetry of BC also causes an increase in southward cross-equatorial heat transport and a resulting northward shift of the inter-tropical convergence zone in the simulations at a rate of 4$^{\\circ}$N $\\textnormal PW^{-1}$. Global average mid- and high-level clouds decrease, whereas the low-level clouds increase linearly with BC. The increase in marine stratocumulus cloud fraction over the south tropical Atlantic is caused by increased BC-induced diabatic heating of the free troposphere.

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

2013-01-01T23:59:59.000Z

256

Clouds of short-circuited thermionic nanobatteries and promising prospects for development of nanobattery-based aerosol fusion reactors. The preliminary report  

E-Print Network [OSTI]

The physical mechanisms of periodic separation and relaxation of electric charges within aerosol particles possessing the properties the short-circuited batteries can be extremely diverse. With use of appropriate materials and dispersing methods, the electrochemical, thermoelectric, thermionic, pyroelectric, photoelectric, photo electronic emission, or even radionuclide-based emission micro and nano-batteries can be synthesized and be dispersed in the air as clouds self-assembed of the short-circuited aerosol batteries due to the inter-particle electromagnetic dipole-dipole attraction. Intense thermionic emission from ionized hot spots migrating on the relatively cold surface of charged explosive particles, can convert these particles into short-circuited thermionic batteries, turning an aerosol cloud consisting of such unipolar charged, gradually decomposing explosive particles into ball lightning. The slow exothermic decomposition of the highly sensitive explosive aerosol particles, catalyzed by excess ions...

Meshcheryakov, Oleg

2012-01-01T23:59:59.000Z

257

DOE research on atmospheric aerosols  

SciTech Connect (OSTI)

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

Schwartz, S.E.

1995-11-01T23:59:59.000Z

258

ARM Aerosol Working Group Meeting  

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

259

ARM - Field Campaign - Carbonaceous Aerosol and Radiative Effects Study  

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

260

Distinguishing Aerosol Impacts on Climate over the Past Century  

Science Journals Connector (OSTI)

Aerosol direct (DE), indirect (IE), and black carbonsnow albedo (BAE) effects on climate between 1890 and 1995 are compared using equilibrium aerosolclimate 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 "ultra-high sensitivity aerosol" 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

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

262

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

SciTech Connect (OSTI)

We propose here a novel approach for retrieving in parallel the effective density and real refractive index of weakly absorbing aerosol from optical and size distribution measurements. Here we define weakly absorbing as aerosol single-scattering albedos that exceed 0.95 at 0.5 um.The required optical measurements are the scattering coefficient and the hemispheric backscatter fraction, obtained in this work from an integrating nephelometer. The required size spectra come from a Scanning Mobility Particle Sizer and an Aerodynamic Particle Sizer. The performance of this approach is first evaluated using a sensitivity study with synthetically generated but measurement-related inputs. The sensitivity study reveals that the proposed approach is robust to random noise; additionally the uncertainties of the retrieval are almost linearly proportional to the measurement errors, and these uncertainties are smaller for the real refractive index than for the effective density. Next, actual measurements are used to evaluate our approach. These measurements include the optical, microphysical, and chemical properties of weakly absorbing aerosol which are representative of a variety of coastal summertime conditions observed during the Two-Column Aerosol Project (TCAP; http://campaign.arm.gov/tcap/). The evaluation includes calculating the root mean square error (RMSE) between the aerosol characteristics retrieved by our approach, and the same quantities calculated using the conventional volume mixing rule for chemical constituents. For dry conditions (defined in this work as relative humidity less than 55%) and sub-micron particles, a very good (RMSE~3%) and reasonable (RMSE~28%) agreement is obtained for the retrieved real refractive index (1.490.02) and effective density (1.680.21), 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

263

The near future availability of photovoltaic energy in Europe and Africa in climate-aerosol modeling experiments  

Science Journals Connector (OSTI)

Abstract The near future change in productivity of photovoltaic energy (PVE) in Europe and Africa is assessed by using the climate variables simulated by the ECHAM5-HAM aerosol-climate model, and a model for the performance of photovoltaic systems. The climate simulations are forced by green-house gases emissions from the IPCC SRES B2 scenario. In addition, different scenarios for future anthropogenic aerosols emissions are applied. Thus, the sensitivity of the future PVE productivity to changes in aerosol atmospheric burdens between 2000 and 2030 is analyzed. The analysis indicates that reductions in aerosols emissions in the near future result in an increase of global warming, and a significant response in surface solar radiation and associated PVE productivity. A statistically significant reduction in PVE productivity up to 7% is observed in eastern Europe and northern Africa, while a significant increase up to 10% is observed in western Europe and eastern Mediterranean. The changes in surface solar radiation and PVE productivity are related to global effects of aerosols reduction on the large scale circulation and associated cloud cover pattern, rather than to local effects on the atmospheric optical properties. PVE assessment is then discussed in the frame of the present situation and next decades evolution of the photovoltaic market, highlighting that the effects on productivity induced by industrial and public policies, and technological development are comparable to climate related effects. The presented results encourage the improvement and further use of climate models in assessment of future renewable energies availability.

Marco Gaetani; Thomas Huld; Elisabetta Vignati; Fabio Monforti-Ferrario; Alessandro Dosio; Frank Raes

2014-01-01T23:59:59.000Z

264

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

265

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

266

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 FrequenciesTables 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...

Vronique 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

267

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

268

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.

269

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.

270

Indirect and Semi-Direct Aerosol Campaign  

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

271

Researchers Model Impact of Aerosols Over California  

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

272

Characterizing the formation of secondary organic aerosols  

SciTech Connect (OSTI)

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

Lunden, Melissa; Black, Douglas; Brown, Nancy

2004-02-01T23:59:59.000Z

273

Aerodynamic Focusing Of High-Density Aerosols  

SciTech Connect (OSTI)

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

Ruiz, D. E.; Fisch, Nathaniel

2014-02-24T23:59:59.000Z

274

Near real time vapor detection and enhancement using aerosol adsorption  

SciTech Connect (OSTI)

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

Novick, Vincent J.; Johnson, Stanley A.

1997-12-01T23:59:59.000Z

275

Technical Note: Estimating Aerosol Effects on Cloud Radiative Forcing  

SciTech Connect (OSTI)

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

Ghan, Steven J.

2013-10-09T23:59:59.000Z

276

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

277

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

278

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

279

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

SciTech Connect (OSTI)

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

280

Understanding Brown Carbon Aerosols and Their Role in Climate Change  

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

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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

Response of California temperature to regional anthropogenic aerosol  

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

282

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

SciTech Connect (OSTI)

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

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

2011-03-02T23:59:59.000Z

283

Impact of natural and anthropogenic aerosols on stratocumulus and precipitation in the Southeast Pacific: A regional modeling study using WRF-Chem  

SciTech Connect (OSTI)

Cloud-system resolving simulations with the chemistry version of the Weather Research and Forecasting (WRF-Chem) model are used to quantify the impacts of regional anthropogenic and oceanic emissions on changes in aerosol properties, cloud macro- and microphysics, and cloud radiative forcing over the Southeast Pacific (SEP) during the VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) (15 OctNov 16, 2008). The effects of oceanic aerosols on cloud properties, precipitation, and the shortwave forcing counteract those of anthropogenic aerosols. Despite the relatively small changes in Na concentrations (2-12%) from regional oceanic emissions, their net effect (direct and indirect) on the surface shortwave forcing is opposite and comparable or even larger in magnitude compared to those of regional anthropogenic emissions over the SEP. Two distinct regions are identified in the VOCALS-REx domain. The near-coast polluted region is characterized with strong droplet activation suppression of small particles by sea-salt particles, the more important role of the first than the second indirect effect, low surface precipitation rate, and low aerosol-cloud interaction strength associated with anthropogenic emissions. The relatively clean remote region is characterized with large contributions of Cloud Condensation Nuclei (CCN, number concentration denoted by NCCN) and droplet number concentrations (Nd) from non-local sources (lateral boundaries), a significant amount of surface precipitation, and high aerosol-cloud interactions under a scenario of five-fold increase in anthropogenic emissions. In the clean region, cloud properties have high sensitivity (e.g., 13% increase in cloud-top height and a 9% surface albedo increase) to the moderate increase in CCN concentration (?Nccn = 13 cm-3; 25%) produced by a five-fold increase in regional anthropogenic emissions. The increased anthropogenic aerosols reduce the precipitation amount over the relatively clean remote ocean. The reduction of precipitation (as a cloud water sink) more than doubles the wet scavenging timescale, resulting in an increased aerosol lifetime in the marine boundary layer. Therefore, the aerosol impacts on precipitation are amplified by the positive feedback of precipitation on aerosol. The positive feedback ultimately alters the cloud micro- and macro-properties, leading to strong aerosol-cloud-precipitation interactions. The higher sensitivity of clouds to anthropogenic aerosols over this region is also related to a 16% entrainment rate increase due to anthropogenic aerosols. The simulated aerosol-cloud-precipitation interactions are stronger at night over the clean marine region, while during the day, solar heating results in more frequent decoupling, thinner clouds, reduced precipitation, and reduced sensitivity to anthropogenic emissions. The simulated high sensitivity to the increased anthropogenic emissions over the clean region suggests that the perturbation of the clean marine environment with anthropogenic aerosols may have a larger effect on climate than that of already polluted marine environments.

Yang, Qing; Gustafson, William I.; Fast, Jerome D.; Wang, Hailong; Easter, Richard C.; Wang, Minghuai; Ghan, Steven J.; Berg, Larry K.; Leung, Lai-Yung R.; Morrison, H.

2012-09-28T23:59:59.000Z

284

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

285

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

286

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

287

ADEPT. aerosol deposition in cylindrical pipes  

SciTech Connect (OSTI)

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

288

ADEPT. Aerosol Deposition in Cylindrical Pipes  

SciTech Connect (OSTI)

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

289

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

290

Direct and semidirect aerosol effects of Southern African biomass burning aerosol  

SciTech Connect (OSTI)

The direct and semi-direct radiative effects of biomass burning aerosols from Southern African fires during July-October are investigated using 20 year runs of the Community Atmospheric Model (CAM) coupled to a slab ocean model. The aerosol optical depth is constrained using observations in clear skies from MODIS and for aerosol layers above clouds from CALIPSO. Over the ocean, where the absorbing biomass burning aerosol layers are primarily located above cloud, negative top of atmosphere (TOA) semi-direct radiative effects associated with increased low cloud cover dominate over a weaker positive all-sky direct radiative effect (DRE). In contrast, over the land where the aerosols are often below or within cloud layers, reductions in cloud liquid water path (LWP) lead to a positive semi-direct radiative effect that dominates over a near-zero DRE. Over the ocean, the cloud response can be understood as a response to increased lower tropospheric stability (LTS) which is caused both by aerosol absorptive warming in overlying layers and surface cooling in response to direct aerosol forcing. The ocean cloud changes are robust to changes in the cloud parameterization (removal of the hard-wired dependence of clouds on LTS), suggesting that they are physically realistic. Over land where cloud cover changes are minimal, decreased LWP is consistent with weaker convection driven by increased static stability. Over the entire region the overall TOA radiative effect from the biomass burning aerosols is almost zero due to opposing effects over the land and ocean. However, the surface forcing is strongly negative requiring a reduction in precipitation. This is primarily realized through reductions in convective precipitation on both the southern and northern flanks of the convective precipitation region spanning the equatorial rainforest and the ITCZ in the southern Sahel. The changes are consistent with the low-level aerosol forced cooling pattern. The results highlight the importance of semi-direct radiative effects and precipitation responses for determining the climatic effects of aerosols in the African region.

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

2011-06-21T23:59:59.000Z

291

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.

292

Clouds, Aerosols and Precipitation in  

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

the Marine Boundary Layer (CAP-MBL) Graciosa Island, Azores, NE Atlantic Ocean Graciosa Island, Azores, NE Atlantic Ocean May 2009-December 2010 May 2009-December 2010 Rob Wood, University of Washington Rob Wood, University of Washington AMF Deployment Team Thanks to Mark Miller: AMF Site Scientist Mark Miller: AMF Site Scientist Kim Nitschke: AMF Site Manager CAP-MBL Proposal Team Importance of Low-Clouds for Climate Imperative that we understand the processes controlling the formation, maintenance and dissipation of low clouds in order to formation, maintenance and dissipation of low clouds in order to improve their representation in climate models. Which clouds matter for climate sensitivity? Cli t F db k

293

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

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

294

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

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

295

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

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

296

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. Pedrs; J.L. Gmez-Amo; C.R. Marcos; M.P. Utrillas; S. Ganda; F. Tena; J.A. Martinez Lozano

297

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

Science Journals Connector (OSTI)

The Georgia Institute of TechnologyGoddard 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

298

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

299

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

300

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.

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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

Priorities for In-situ Aerosol Measurements  

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

302

Aerosol and graphitic carbon content of snow  

SciTech Connect (OSTI)

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

303

Focus Sensitive Coordination  

E-Print Network [OSTI]

This thesis investigates the role of the Focus Sensitive Operators (FSOs) even and also when found inside of a coordination. Coordinations of this form are called Focus Sensitive Coordinations (FSC) and include or even, ...

Hulsey, Sarah McNearney

2008-01-01T23:59:59.000Z

304

Desert dust and anthropogenic aerosol interactions in the Community Climate System Model coupled-carbon-climate model  

SciTech Connect (OSTI)

Coupled-carbon-climate simulations are an essential tool for predicting the impact of human activity onto the climate and biogeochemistry. Here we incorporate prognostic desert dust and anthropogenic aerosols into the CCSM3.1 coupled carbon-climate model and explore the resulting interactions with climate and biogeochemical dynamics through a series of transient anthropogenic simulations (20th and 21st centuries) and sensitivity studies. The inclusion of prognostic aerosols into this model has a small net global cooling effect on climate but does not significantly impact the globally averaged carbon cycle; we argue that this is likely to be because the CCSM3.1 model has a small climate feedback onto the carbon cycle. We propose a mechanism for including desert dust and anthropogenic aerosols into a simple carbon-climate feedback analysis to explain the results of our and previous studies. Inclusion of aerosols has statistically significant impacts on regional climate and biogeochemistry, in particular through the effects on the ocean nitrogen cycle and primary productivity of altered iron inputs from desert dust deposition.

Mahowald, Natalie [Cornell University; Rothenberg, D. [Cornell University; Lindsay, Keith [National Center for Atmospheric Research (NCAR); Doney, Scott C. [Woods Hole Oceanographic Institution; Moore, Jefferson Keith [University of California, Irvine; Randerson, James T. [University of California, Irvine; Thornton, Peter E [ORNL; Jones, C. D. [Hadley Center, Devon, England

2011-02-01T23:59:59.000Z

305

Safeguards over sensitive technology  

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

Safeguards Over Sensitive Technology Safeguards Over Sensitive Technology DOE/IG-0635 January 2004 Program Results and Cost Details of Finding ....................................................................... 1 Recommendations and Comments ........................................... 6 Appendices Prior Reports .............................................................................. 9 Objective, Scope, and Methodology ........................................ 11 Management Comments .......................................................... 12 SAFEGUARDS OVER SENSITIVE TECHNOLOGY TABLE OF CONTENTS Page 1 Background Aspects of sensitive technology protection, along with related impacts on national security, have been addressed in various formats by the Department of Energy and several other Federal agencies. For example:

306

On The Importance of Organic Oxygen for Understanding Organic Aerosol  

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

307

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

308

ARM AOS Processing Status and Aerosol Intensive Properties VAP  

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

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

309

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

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

310

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

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

311

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 Lhde; Topi Rnkk; Annele Virtanen; Tanja J. Schuck; Liisa Pirjola; Kaarle Hmeri; Markku Kulmala; Frank Arnold; Dieter Rothe; Jorma Keskinen

2008-12-09T23:59:59.000Z

312

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

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

313

aerosol influenza transmission: Topics by E-print Network  

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

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

314

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

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

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

315

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

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

316

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

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

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

317

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

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

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

318

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

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

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

319

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

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

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

320

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

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

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


321

Aerosol-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

322

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

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

323

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

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

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

324

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...

325

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

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

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

326

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

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

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

327

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

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

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

328

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

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

329

Development and Characterization of a Thermodenuder for Aerosol Volatility Measurements  

SciTech Connect (OSTI)

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

Dr. Timothy Onasch

2009-09-09T23:59:59.000Z

330

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

SciTech Connect (OSTI)

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

331

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

332

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

333

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

334

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

335

Determination of vertical profiles of aerosol extinction, single scatter  

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

336

ARM - Field Campaign - MArine Stratus Radiation Aerosol and Drizzle  

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

337

Aerosol Retrievals under Partly Cloudy Conditions: Challenges and Perspectives  

SciTech Connect (OSTI)

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

338

Do Diurnal Aerosol Changes Affect Daily Average Radiative Forcing?  

SciTech Connect (OSTI)

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

339

Experiments related to the resuspension of aerosols during hydrogen burns  

SciTech Connect (OSTI)

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

340

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

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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

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

342

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

343

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

SciTech Connect (OSTI)

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

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

2013-10-25T23:59:59.000Z

344

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

345

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

346

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

347

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.

348

Hyperspectral Aerosol Optical Depths from TCAP Flights  

SciTech Connect (OSTI)

4STAR (Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research), the worlds 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 4STARs 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

349

Sulfate aerosols and polar stratospheric cloud formation  

SciTech Connect (OSTI)

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

350

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

351

The Two-Column Aerosol Project (TCAP) Science Plan  

SciTech Connect (OSTI)

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

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

2011-07-27T23:59:59.000Z

352

Sensitivity study of the residue method for the detection of aerosols from space-borne sensors  

E-Print Network [OSTI]

and absorption of solar radiation, and indirectly as cloud condensation nu- clei. The large climate modification

Stoffelen, Ad

353

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

SciTech Connect (OSTI)

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

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

2010-05-01T23:59:59.000Z

354

Constrained sensitivity theory  

SciTech Connect (OSTI)

In sensitivity and uncertainty analysis of to-be-built reactors it is customary to use k-reset sensitivity functions - accounting for the combined effects of the change (or uncertainty) in the input data and of the alteration in some design variable applied to maintain criticality. Critical reactors are usually subjected to several constraints, such as power peaking factor and breeding ratio constraints, in addition to the criticality constraint. Perturbation theory formulations which can account, simultaneously, for several constraints both in critical reactors and in source driven systems (such as radiation shields and blankets of fusion devices) are presented. All the sensitivity and uncertainty analyses of source driven systems carried out so far used unconstrained sensitivity functions despite the fact that such systems can be also subjected to a variety of constraints.

Greenspan, E.; Williams, M.L.

1980-01-01T23:59:59.000Z

355

Aerosol-Based Duct Sealing Technology  

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

356

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

357

Discrimination between thin cirrus and and tropospheric aerosol using  

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

358

Mobile Climate Observatory for Atmospheric Aerosols in India  

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

359

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

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

360

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

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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

A New Assessment of the Aerosol First Indirect Effect  

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

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

362

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

363

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

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

364

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

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

365

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

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

366

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

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

367

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

368

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

369

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

370

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 (CAM4SOM) ...

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

2013-10-01T23:59:59.000Z

371

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

372

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

373

Continuous air monitor for alpha-emitting aerosol particles  

SciTech Connect (OSTI)

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

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

1990-01-01T23:59:59.000Z

374

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

375

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

376

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

377

Atmospheric Aerosol Chemistry, Climate Change, and Air Quality  

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

378

ARM - Field Campaign - Shortwave Radiation and Aerosol Intensive  

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

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.

379

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

SciTech Connect (OSTI)

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

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

1995-06-01T23:59:59.000Z

380

Representing Cloud Processing of Aerosol in Numerical Models  

SciTech Connect (OSTI)

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

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

2005-03-18T23:59:59.000Z

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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

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

382

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

SciTech Connect (OSTI)

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

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

2009-03-05T23:59:59.000Z

383

On modification of global warming by sulfate aerosols  

SciTech Connect (OSTI)

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

384

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

385

Ganges Valley Aerosol Experiment: Science and Operations Plan  

SciTech Connect (OSTI)

The Ganges Valley region is one of the largest and most rapidly developing sections of the Indian subcontinent. The Ganges River, which provides the region with water needed for sustaining life, is fed primarily by snow and rainfall associated with Indian summer monsoons. Impacts of changes in precipitation patterns, temperature, and the flow of the snow-fed rivers can be immense. Recent satellite-based measurements have indicated that the upper Ganges Valley has some of the highest persistently observed aerosol optical depth values. The aerosol layer covers a vast region, extending across the Indo-Gangetic Plain to the Bay of Bengal during the winter and early spring of each year. The persistent winter fog in the region is already a cause of much concern, and several studies have been proposed to understand the economic, scientific, and societal dimensions of this problem. During the INDian Ocean EXperiment (INDOEX) field studies, aerosols from this region were shown to affect cloud formation and monsoon activity over the Indian Ocean. This is one of the few regions showing a trend toward increasing surface dimming and enhanced mid-tropospheric warming. Increasing air pollution over this region could modify the radiative balance through direct, indirect, and semi-indirect effects associated with aerosols. The consequences of aerosols and associated pollution for surface insolation over the Ganges Valley and monsoons, in particular, are not well understood. The proposed field study is designed for use of (1) the ARM Mobile Facility (AMF) to measure relevant radiative, cloud, convection, and aerosol optical characteristics over mainland India during an extended period of 912 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 612 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 abundancein 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

386

Effect of Terrestrial and Marine Organic Aerosol on Regional and Global Climate: Model Development, Application, and Verification with Satellite Data  

SciTech Connect (OSTI)

In this DOE project the improvements to parameterization of marine primary organic matter (POM) emissions, hygroscopic properties of marine POM, marine isoprene derived secondary organic aerosol (SOA) emissions, surfactant effects, new cloud droplet activation parameterization have been implemented into Community Atmosphere Model (CAM 5.0), with a seven mode aerosol module from the Pacific Northwest National Laboratory (PNNL)???¢????????s Modal Aerosol Model (MAM7). The effects of marine aerosols derived from sea spray and ocean emitted biogenic volatile organic compounds (BVOCs) on microphysical properties of clouds were explored by conducting 10 year CAM5.0-MAM7 model simulations at a grid resolution 1.9???????°????????2.5???????° with 30 vertical layers. Model-predicted relationship between ocean physical and biological systems and the abundance of CCN in remote marine atmosphere was compared to data from the A-Train satellites (MODIS, CALIPSO, AMSR-E). Model simulations show that on average, primary and secondary organic aerosol emissions from the ocean can yield up to 20% increase in Cloud Condensation Nuclei (CCN) at 0.2% Supersaturation, and up to 5% increases in droplet number concentration of global maritime shallow clouds. Marine organics were treated as internally or externally mixed with sea salt. Changes associated with cloud properties reduced (absolute value) the model-predicted short wave cloud forcing from -1.35 Wm-2 to -0.25 Wm-2. By using different emission scenarios, and droplet activation parameterizations, this study suggests that addition of marine primary aerosols and biologically generated reactive gases makes an important difference in radiative forcing assessments. All baseline and sensitivity simulations for 2001 and 2050 using global-through-urban WRF/Chem (GU-WRF) were completed. The main objective of these simulations was to evaluate the capability of GU-WRF for an accurate representation of the global atmosphere by exploring the most accurate configuration of physics options in GWRF for global scale modeling in 2001 at a horizontal grid resolution of 1???????° x 1???????°. GU-WRF model output was evaluated using observational datasets from a variety of sources including surface based observations (NCDC and BSRN), model reanalysis (NCEP/ NCAR Reanalysis and CMAP), and remotely-sensed data (TRMM) to evaluate the ability of GU-WRF to simulate atmospheric variables at the surface as well as aloft. Explicit treatment of nanoparticles produced from new particle formation in GU-WRF/Chem-MADRID was achieved by expanding particle size sections from 8 to 12 to cover particles with the size range of 1.16 nm to 11.6 ???????µm. Simulations with two different nucleation parameterizations were conducted for August 2002 over a global domain at a 4???????º by 5???????º horizontal resolution. The results are evaluated against field measurement data from the 2002 Aerosol Nucleation and Real Time Characterization Experiment (ANARChE) in Atlanta, Georgia, as well as satellite and reanalysis data. We have also explored the relationship between ???¢????????clean marine???¢??????? aerosol optical properties and ocean surface wind speed using remotely sensed data from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) on board the CALIPSO satellite and the Advanced Microwave Scanning Radiometer (AMSR-E) on board the AQUA satellite. Detailed data analyses

Meskhidze, Nicholas; Zhang, Yang; Kamykowski, Daniel

2012-03-28T23:59:59.000Z

387

Ultra-high-energy debris from the collisional Penrose process  

E-Print Network [OSTI]

Soon after the discovery of the Kerr metric, Penrose realized that superradiance can be exploited to extract energy from black holes. The original idea (involving the breakup of a single particle) yields only modest energy gains. A variant of the Penrose process consists of particle collisions in the ergoregion. The collisional Penrose process has been explored recently in the context of dark matter searches, with the conclusion that the ratio $\\eta$ between the energy of post-collision particles detected at infinity and the energy of the colliding particles should be modest ($\\eta \\lesssim 1.5$). Schnittman has shown that these studies underestimated the maximum efficiency by about one order of magnitude (i.e., $\\eta \\lesssim 15$). In this work we reach an even more striking conclusion: particle collisions in the vicinity of rapidly rotating black holes can result in arbitrarily high efficiencies. The astrophysical likelihood of these events deserves further scrutiny, but our study hints at the tantalizing p...

Berti, Emanuele; Cardoso, Vitor

2014-01-01T23:59:59.000Z

388

On the acceleration of ultra-high-energy cosmic rays  

Science Journals Connector (OSTI)

...experiments have reported the discovery of a high-energy cut-off in the UHECR spectrum...observed. However, the discovery of the high-energy cut-off disfavours this...also black-hole physics, dark energy and the cosmological constant...

2008-01-01T23:59:59.000Z

389

Structural Engineering Seminar Series Ultra-High Performance Concrete Construction  

E-Print Network [OSTI]

performance and resistance against environmental degradation. UHPC is defined as a concrete fiber composite for Our Future Infrastructure? by Kay Wille, PhD Assistant Professor, Civil and Environmental Engineering and conference proceedings. It has been used in various forms in structural and architectural elements, as a bond

Kamat, Vineet R.

390

Ultra High Energy Cosmic Rays: origin and propagation  

E-Print Network [OSTI]

We discuss the basic difficulties in understanding the origin of the highest energy particles in the Universe - the ultrahigh energy cosmic rays (UHECR). It is difficult to imagine the sources they are accelerated in. Because of the strong attenuation of UHECR on their propagation from the sources to us these sources should be at cosmologically short distance from us but are currently not identified. We also give information of the most recent experimental results including the ones reported at this conference and compare them to models of the UHECR origin.

Todor Stanev

2007-11-14T23:59:59.000Z

391

CLINICAL SCIENCES High-Speed UltraHigh-Resolution Optical  

E-Print Network [OSTI]

in Hydroxychloroquine Retinopathy Julio A. Rodriguez-Padilla, MD; Thomas R. Hedges III, MD; Bryan Monson, BS; Vivek Srinivasan, MS; Maciej Wojtkowski, PhD; Elias Reichel, MD; Jay S. Duker, MD; Joel S. Schuman, MD; James G, Boston, Mass (Drs Rodriguez-Padilla, Hedges, Reichel, and Duker and Mr Monson); Department of Electrical

Srinivasan, Vivek J.

392

Ultra high vacuum heating and rotating specimen stage  

DOE Patents [OSTI]

A heating and rotating specimen stage provides for simultaneous specimen heating and rotating. The stage is ideally suited for operation in ultrahigh vacuum (1.times.10.sup.-9 torr or less), but is useful at atmosphere and in pressurized systems as well. A specimen is placed on a specimen holder that is attached to a heater that, in turn, is attached to a top housing. The top housing is rotated relative to a bottom housing and electrically connected thereto by electrically conductive brushes. This stage is made of materials that are compatible with UHV, able to withstand high temperatures, possess low outgassing rates, are gall and seize resistant, and are able to carry substantial electrical loading without overheating.

Coombs, III, Arthur W. (Patterson, CA)

1995-01-01T23:59:59.000Z

393

Ultra high vacuum heating and rotating specimen stage  

DOE Patents [OSTI]

A heating and rotating specimen stage provides for simultaneous specimen heating and rotating. The stage is ideally suited for operation in ultrahigh vacuum (1{times}10{sup {minus}9} torr or less), but is useful at atmosphere and in pressurized systems as well. A specimen is placed on a specimen holder that is attached to a heater that, in turn, is attached to a top housing. The top housing is rotated relative to a bottom housing and electrically connected thereto by electrically conductive brushes. This stage is made of materials that are compatible with UHV, able to withstand high temperatures, possess low outgassing rates, are gall and seize resistant, and are able to carry substantial electrical loading without overheating. 5 figs.

Coombs, A.W. III

1995-05-02T23:59:59.000Z

394

Ultra high performance connectors for power transmission applications  

DOE Patents [OSTI]

Disclosed are several examples of an apparatus for connecting the free ends of two electrical power transmission lines having conductor strands disposed around a central, reinforcing core. The examples include an inner sleeve having a body defining an inner bore passing through an axially-extending, central axis, an outer rim surface disposed radially outward from the central bore, and one or more axially-extending grooves penetrating the body at the outer rim surface. Also included is an outer splice having a tubular shaped body with a bore passing coaxially through the central axis, the bore defining an inner rim surface for accepting the inner sleeve. The inner bore of the inner sleeve accepts the reinforcement cores of the two conductors, and the grooves accept the conductor strands in an overlapping configuration so that a majority of the electrical current flows between the overlapped conductor strands when the conductors are transmitting electrical current.

Wang, Jy-An; Ren, Fei; Lee, Dominic F; Jiang, Hao

2014-03-04T23:59:59.000Z

395

New US Ultra High Efficiency R&D Programme  

E-Print Network [OSTI]

Very high efficiency is an important characteristic of the value proposition for solar to electric conversion. High efficiency is the shortest path to cost-effective commercial applications and leads to new high value applications such as portable battery charging. The Defense Advanced Research Projects Agency has initiated the Very High Efficiency Solar Cell (VHESC) program to address the critical need of the soldier for power in the field. Very High Efficiency Solar Cells for portable applications1,2 that operate at greater than 55 percent efficiency in the laboratory and 50 percent in production are being developed. We are integrating the optical design with the solar cell design, and have entered previously unoccupied design space that leads to a new architecture paradigm. An integrated team effort is now underway that requires us to invent, develop and transfer to production these new solar cells. Our approach is driven by proven quantitative models for the solar cell design, the optical design and the integration of these designs. We start with a very high performance crystalline silicon solar cell platform. Examples will be presented. Initial solar cell device results are shown for devices fabricated in geometries designed for this VHESC Program.

Allen Barnett Douglas Kirkpatrick

396

Energy spectrum of ultra high energy cosmic rays  

E-Print Network [OSTI]

The construction of the southern site of the Pierre Auger Observatory is almost completed. Three independent measurements of the flux of the cosmic rays with energies larger than 1 EeV have been performed during the construction phase. The surface detector data collected until August 2007 have been used to establish a flux suppression at the highest energies with a 6 sigma significance. The observations of cosmic rays by the fluorescence detector allowed the extension of the energy spectrum to lower energies, where the efficiency of the surface detector is less than 100% and a change in the spectral index is expected.

Ioana C. Maris; for the Pierre Auger Collaboration

2008-08-12T23:59:59.000Z

397

Precipitation kinetics in ultra-high lime softening  

E-Print Network [OSTI]

. The second model used the crystal growth rate as an alternate measure of supersaturation. The growth rate obtained from a settling procedure correlated well with values for silica removal rates for experiments grouped by pH and recycie conditions... of precipitation processes specific applications to lime soFtening and silica removal can be addressed. Mechanisms oF silica raawal. Many of the processes studied for specific removal of silica From industrial water have relied on adsorption...

Peacock, Edward Dale

1986-01-01T23:59:59.000Z

398

Ultra-High Temperature Sensors Based on Optical Property  

SciTech Connect (OSTI)

In this program, Nuonics, Inc. has studied the fundamentals of a new Silicon Carbide (SiC) materials-based optical sensor technology suited for extreme environments of coal-fired engines in power production. The program explored how SiC could be used for sensing temperature, pressure, and potential gas species in a gas turbine environment. The program successfully demonstrated the optical designs, signal processing and experimental data for enabling both temperature and pressure sensing using SiC materials. The program via its sub-contractors also explored gas species sensing using SiC, in this case, no clear commercially deployable method was proven. Extensive temperature and pressure measurement data using the proposed SiC sensors was acquired to 1000 deg-C and 40 atms, respectively. Importantly, a first time packaged all-SiC probe design was successfully operated in a Siemens industrial turbine rig facility with the probe surviving the harsh chemical, pressure, and temperature environment during 28 days of test operations. The probe also survived a 1600 deg-C thermal shock test using an industrial flame.

Nabeel Riza

2008-09-30T23:59:59.000Z

399

Acceleration of ULtra High Energy Cosmic Rays: Cosmic Zevatrons?  

E-Print Network [OSTI]

In this lecture I outline some of the underlying physics issues associated with accelerators plausibly capable of explaining the UHECRs up to ZeV energies. I concentrate on the concentrate on mechanisms and their constraints, but provide a brief background on on observations and the constraints they supply, as well.

T. W. Jones

2002-10-21T23:59:59.000Z

400

Ultra- high pulse intensity amplification and compression in plasma  

Science Journals Connector (OSTI)

This talk provides the summary of experimental research at Princeton on Raman Backscattering (RBS) amplification and compression in plasma [1]. The main subject of the talk is about...

Morozov, Anatoli; Li, Shuanglei; Turnbull, David; Suckewer, Szymon

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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

Ionization monitor with improved ultra-high megohm resistor  

DOE Patents [OSTI]

An ionization monitor measures extremely small currents using a resistor containing a beta emitter to generate ion-pairs which are collected as current when the device is used as a feedback resistor in an electrometer circuit. By varying the amount of beta emitter, the resistance of the resistor may be varied.

Burgess, Edward T. (Carlisle, OH)

1988-11-05T23:59:59.000Z

402

Ultra-High Intensity Magnetic Field Generation in Dense Plasma  

SciTech Connect (OSTI)

I. Grant Objective The main objective of this grant proposal was to explore the efficient generation of intense currents. Whereasthefficient generation of electric current in low-?energy-? density plasma has occupied the attention of the magnetic fusion community for several decades, scant attention has been paid to carrying over to high-?energy-? density plasma the ideas for steady-?state current drive developed for low-?energy-? density plasma, or, for that matter, to inventing new methodologies for generating electric current in high-?energy-?density plasma. What we proposed to do was to identify new mechanisms to accomplish current generation, and to assess the operation, physics, and engineering basis of new forms of current drive in regimes appropriate for new fusion concepts.

Fisch, Nathaniel J

2014-01-08T23:59:59.000Z

403

An Aerosol Condensation Model for Sulfur Trioxide  

SciTech Connect (OSTI)

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

Grant, K E

2008-02-07T23:59:59.000Z

404

NANOCOMPOSITE ENABLED SENSITIZED SOLAR CELL  

E-Print Network [OSTI]

by Dye-Sensitized Photovoltaic cells. Inorganic Chemistry,by Dye-Sensitized Photovoltaic Cells. Inorganic ChemistryThe characteristics of a photovoltaic cell. Generally,

Phuyal, Dibya

2012-01-01T23:59:59.000Z

405

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

406

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

SciTech Connect (OSTI)

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

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

2006-10-01T23:59:59.000Z

407

MATERIALS AND MOLECULAR RESEARCH DIVISION. ANNUAL REPORT 1980  

E-Print Network [OSTI]

ultra-high sensitive far in frared bolometric detectors to temperatures in the he neighborhood of 100 mk.

Searcy, Alan W.

2010-01-01T23:59:59.000Z

408

Phase sensitivity in electroreception  

Science Journals Connector (OSTI)

...and that pro-Electric organ discharges (EOD's) in gymnotoid electric fish show high...frequencies near that of the particular species' EOD (2, 4, 5) and very similar "tuning...Electric fish are thus most sensitive to EOD's oftheir own species and the variability...

W Heiligenberg; RA Altes

1978-03-03T23:59:59.000Z

409

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

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

410

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

411

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

412

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

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

413

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

414

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

415

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

416

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

417

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

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

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

418

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

419

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 Valds

2009-02-01T23:59:59.000Z

420

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

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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

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

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

422

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

423

NANOCOMPOSITE ENABLED SENSITIZED SOLAR CELL  

E-Print Network [OSTI]

solar cell The history of dye sensitization dates back to the photosensitization phenomenon by organic

Phuyal, Dibya

2012-01-01T23:59:59.000Z

424

Parameterizations of Cloud Microphysics and Indirect Aerosol Effects  

SciTech Connect (OSTI)

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

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

2014-05-19T23:59:59.000Z

425

CARES: Carbonaceous Aerosol and Radiative Effects Study Operations Plan  

SciTech Connect (OSTI)

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

Zaveri, RA; Shaw, WJ; Cziczo, DJ

2010-07-12T23:59:59.000Z

426

Aerosol Data Sources and Their Roles within PARAGON  

SciTech Connect (OSTI)

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

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

2004-10-01T23:59:59.000Z

427

Calculating Capstone Depleted Uranium Aerosol Concentrations from Beta Activity Measurements  

SciTech Connect (OSTI)

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

428

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

SciTech Connect (OSTI)

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

429

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

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

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

430

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

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

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

431

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

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

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

432

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

Broader source: Energy.gov [DOE]

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

433

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

434

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

435

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

436

Surface based remote sensing of aerosol-cloud interactions  

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

437

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

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

438

ARM - Evaluation Product - Aerosol Optical Depths from SASHE  

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

439

Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant Particles  

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

440

Direct Aerosol Forcing in the Infrared at the SGP Site?  

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

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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

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

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

442

Lognormal Size Distribution Theory for Deposition of Polydisperse Aerosol Particles  

SciTech Connect (OSTI)

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

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

2000-07-15T23:59:59.000Z

443

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

444

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

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

445

Airborne measurements of carbonaceous aerosols in southern Africa during  

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

446

Distinguishing Aerosol Impacts on Climate Over the Past Century  

SciTech Connect (OSTI)

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

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

2008-08-22T23:59:59.000Z

447

Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant  

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

448

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

449

Final Project Report - ARM CLASIC CIRPAS Twin Otter Aerosol  

SciTech Connect (OSTI)

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

John A. Ogren

2010-04-05T23:59:59.000Z

450

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

451

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

452

Analysis of the causes of heavy aerosol pollution in Beijing, China: A case study with the WRF-Chem model  

Science Journals Connector (OSTI)

Abstract The causes and variability of a heavy haze episode in the Beijing region was analyzed. During the episode, the PM2.5 concentration reached a peak value of 450?g/kg on January 18, 2013 and rapidly decreased to 100?g/kg on January 19, 2013, characterizing a large variability in a very short period. This strong variability provides a good opportunity to study the causes of the haze formation. The in situ measurements (including surface meteorological data and vertical structures of the winds, temperature, humidity, and planetary boundary layer (PBL)) together with a chemical/dynamical regional model (WRF-Chem) were used for the analysis. In order to understand the rapid variability of the PM2.5 concentration in the episode, the correlation between the measured meteorological data (including wind speed, PBL height, relative humidity, etc.) and the measured particle concentration (PM2.5 concentration) was studied. In addition, two sensitive model experiments were performed to study the effect of individual contribution from local emissions and regional surrounding emissions to the heavy haze formation. The results suggest that there were two major meteorological factors in controlling the variability of the PM2.5 concentration, namely, surface wind speed and PBL height. During high wind periods, the horizontal transport of aerosol particles played an important role, and the heavy haze was formed when the wind speeds were very weak (less than 1m/s). Under weak wind conditions, the horizontal transport of aerosol particles was also weak, and the vertical mixing of aerosol particles played an important role. As a result, the PBL height was a major factor in controlling the variability of the PM2.5 concentration. Under the shallow PBL height, aerosol particles were strongly confined near the surface, producing a high surface PM2.5 concentration. The sensitivity model study suggests that the local emissions (emissions from the Beijing region only) were the major cause for the heavy haze events. With only local emissions, the calculated peak value of the PM2.5 concentration was 350?g/kg, which accounted for 78% of the measured peak value (450?g/kg). In contrast, without the local emissions, the calculated peak value of the PM2.5 concentration was only 100?g/kg, which accounted for 22% of the measured peak value.

Hui He; Xuexi Tie; Qiang Zhang; Xiange Liu; Qian Gao; Xia Li; Yang Gao

2014-01-01T23:59:59.000Z

453

Surveillance metrics sensitivity study.  

SciTech Connect (OSTI)

In September of 2009, a Tri-Lab team was formed to develop a set of metrics relating to the NNSA nuclear weapon surveillance program. The purpose of the metrics was to develop a more quantitative and/or qualitative metric(s) describing the results of realized or non-realized surveillance activities on our confidence in reporting reliability and assessing the stockpile. As a part of this effort, a statistical sub-team investigated various techniques and developed a complementary set of statistical metrics that could serve as a foundation for characterizing aspects of meeting the surveillance program objectives. The metrics are a combination of tolerance limit calculations and power calculations, intending to answer level-of-confidence type questions with respect to the ability to detect certain undesirable behaviors (catastrophic defects, margin insufficiency defects, and deviations from a model). Note that the metrics are not intended to gauge product performance but instead the adequacy of surveillance. This report gives a short description of four metrics types that were explored and the results of a sensitivity study conducted to investigate their behavior for various inputs. The results of the sensitivity study can be used to set the risk parameters that specify the level of stockpile problem that the surveillance program should be addressing.

Hamada, Michael S. (Los Alamos National Laboratory); Bierbaum, Rene Lynn; Robertson, Alix A. (Lawrence Livermore Laboratory)

2011-09-01T23:59:59.000Z

454

Surveillance Metrics Sensitivity Study  

SciTech Connect (OSTI)

In September of 2009, a Tri-Lab team was formed to develop a set of metrics relating to the NNSA nuclear weapon surveillance program. The purpose of the metrics was to develop a more quantitative and/or qualitative metric(s) describing the results of realized or non-realized surveillance activities on our confidence in reporting reliability and assessing the stockpile. As a part of this effort, a statistical sub-team investigated various techniques and developed a complementary set of statistical metrics that could serve as a foundation for characterizing aspects of meeting the surveillance program objectives. The metrics are a combination of tolerance limit calculations and power calculations, intending to answer level-of-confidence type questions with respect to the ability to detect certain undesirable behaviors (catastrophic defects, margin insufficiency defects, and deviations from a model). Note that the metrics are not intended to gauge product performance but instead the adequacy of surveillance. This report gives a short description of four metrics types that were explored and the results of a sensitivity study conducted to investigate their behavior for various inputs. The results of the sensitivity study can be used to set the risk parameters that specify the level of stockpile problem that the surveillance program should be addressing.

Bierbaum, R; Hamada, M; Robertson, A

2011-11-01T23:59:59.000Z

455

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

SciTech Connect (OSTI)

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

456

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

457

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

SciTech Connect (OSTI)

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

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

2013-02-07T23:59:59.000Z

458

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

459

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.

460

Soft ionization of thermally evaporated hypergolic ionic liquid aerosols  

SciTech Connect (OSTI)

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

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

2012-03-16T23:59:59.000Z

Note: This page contains sample records for the topic "ultra-high sensitivity aerosol" 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

Building America Webinar: Sealing of Home Enclosures with Aerosol Particles  

Broader source: Energy.gov [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.

462

LESSONS LEARNED IN AEROSOL MONITORING WITH THE RASA  

SciTech Connect (OSTI)

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

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

2011-09-14T23:59:59.000Z

463

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

464

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

465

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

466

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

467

Correction to Hyperspectral Aerosol Optical Depths from TCAP Flights  

SciTech Connect (OSTI)

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

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

2014-02-16T23:59:59.000Z

468

Unattended Monitoring of HEU Production in Gaseous Centrifuge Enrichment Plants using Automated Aerosol Collection and Laser-based Enrichment Assay  

SciTech Connect (OSTI)

Nuclear power is enjoying rapid growth as government energy policies and public demand shift toward low carbon energy production. Pivotal to the global nuclear power renaissance is the development and deployment of robust safeguards instrumentation that allows the limited resources of the IAEA to keep pace with the expansion of the nuclear fuel cycle. Undeclared production of highly enriched uranium (HEU) remains a primary proliferation concern for modern gaseous centrifuge enrichment plants (GCEPs), due to their massive separative work unit (SWU) processing power and comparably short cascade equilibrium timescale. The Pacific Northwest National Laboratory is developing an unattended safeguards instrument, combining continuous aerosol particulate collection with uranium isotope assay, to provide timely detection of HEU production within a GCEP. This approach is based on laser vaporization of aerosol particulates, followed by laser spectroscopy to characterize the uranium enrichment level. Our prior investigation demonstrated single-shot detection sensitivity approaching the femtogram range and relative isotope ratio uncertainty better than 10% using gadolinium as a surrogate for uranium. In this paper we present measurement results on standard samples containing traces of depleted, natural, and low enriched uranium, as well as measurements on aerodynamic size uranium particles mixed in background materials (e.g., dust, minerals, soils). Improvements and optimizations in the detection electronics, signal timing, calibration, and laser alignment have lead to significant improvements in detection sensitivity and enrichment accuracy, contributing to an overall reduction in the false alarm probability. The sample substrate media was also found to play a significant role in facilitating laser-induced vaporization and the production of energetic plasma conditions, resulting in ablation optimization and further improvements in the isotope abundance sensitivity.

Anheier, Norman C.; Bushaw, Bruce A.

2010-08-11T23:59:59.000Z

469

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

470

Determination of free Bisphenol A (BPA) concentrations in breast milk of U.S. women using a sensitive LC/MS/MS method  

Science Journals Connector (OSTI)

Abstract Bisphenol A (BPA) is a synthetic, endocrine-disrupting compound. Free BPA has been detected in human samples indicating that humans are internally exposed to estrogenically active BPA. The purpose of this study was to develop a sensitive method to detect free BPA in human breast milk. BPA was isolated from the milk of 21 nursing mothers in the U.S. by solid-phase extraction. It was then derivatized to improve sensitivity and subsequently analyzed by ultra high performance liquid chromatographytandem mass spectrometry. Free BPA was detected in 62% of the milk samples (?0.2210.8ngmL?1, median 0.68ngmL?1, mean 3.13ngmL?1). No statistical difference in BPA concentrations was observed between women with a low or high Body Mass Index (BMI) (30 (n=10), respectively). However, there was a significant association between BPA concentration and race. Caucasian women had significantly higher levels of free BPA in their breast milk than non-Caucasian women (mean=4.44 (n=14) and 0.52 (n=7), respectively; pBPA exposure, particularly during pregnancy and lactation.

Stephanie M. Zimmers; Eva P. Browne; Patrick W. OKeefe; Douglas L. Anderton; Lawrence Kramer; David A. Reckhow; Kathleen F. Arcaro

2014-01-01T23:59:59.000Z

471

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

SciTech Connect (OSTI)

The regional-scale Weather Research and Forecasting (WRF) model is being used by a DOE Earth System Modeling (ESM) project titled Improving the Characterization of Clouds, Aerosols and the Cryosphere in Climate Models to evaluate the performance of atmospheric process modules that treat aerosols and aerosol radiative forcing in the Arctic. We are using a regional-scale modeling framework for three reasons: (1) It is easier to produce a useful comparison to observations with a high resolution model; (2) We can compare the behavior of the CAM parameterization suite with some of the more complex and computationally expensive parameterizations used in WRF; (3) we can explore the behavior of this parameterization suite at high resolution. Climate models like the Community Atmosphere Model version 5 (CAM5) being used within the Community Earth System Model (CESM) will not likely be run at mesoscale spatial resolutions (1020 km) until 510 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

472

SECURITY ANALYSIS OF PROPOSEDTRAVELTO SENSITIVE COUNTRIES | Department...  

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

SECURITY ANALYSIS OF PROPOSEDTRAVELTO SENSITIVE COUNTRIES SECURITY ANALYSIS OF PROPOSEDTRAVELTO SENSITIVE COUNTRIES Form is used to document travel to sensitive countries. SECURITY...

473

An Observed Signature of Aerosol Effect on Cloud Droplet Radii from a  

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

474