National Library of Energy BETA

Sample records for 2004-2013 equatorial guinea

  1. Lake Charles, LA Natural Gas LNG Imports from Equatorial Guinea...

    U.S. Energy Information Administration (EIA) Indexed Site

    Lake Charles, LA Natural Gas LNG Imports from Equatorial Guinea (Dollars per Thousand Cubic Feet) Lake Charles, LA Natural Gas LNG Imports from Equatorial Guinea (Dollars per ...

  2. ,"U.S. Liquefied Natural Gas Imports From Equatorial Guinea ...

    U.S. Energy Information Administration (EIA) Indexed Site

    Equatorial Guinea (MMcf)" ,"Click worksheet name or tab at bottom for data" ,"Worksheet ... Natural Gas Imports From Equatorial Guinea (MMcf)",1,"Monthly","122015" ,"Release ...

  3. ,"Price of U.S. Liquefied Natural Gas Imports From Equatorial...

    U.S. Energy Information Administration (EIA) Indexed Site

    Equatorial Guinea (Dollars per Thousand Cubic Feet)" ,"Click worksheet name or tab at ... Natural Gas Imports From Equatorial Guinea (Dollars per Thousand Cubic ...

  4. Price of Elba Island, GA Natural Gas LNG Imports from Equatorial...

    U.S. Energy Information Administration (EIA) Indexed Site

    Equatorial Guinea (Dollars per Thousand Cubic Feet) Price of Elba Island, GA Natural Gas LNG Imports from Equatorial Guinea (Dollars per Thousand Cubic Feet) Decade Year-0 Year-1 ...

  5. Equatorial Guinea: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    by building new gas-fired power stations and investing in the construction of new dams.Work is ongoing on the Djibloho hydroelectric plant project on the Wele River near...

  6. U.S. LNG Imports from Equatorial Guinea

    U.S. Energy Information Administration (EIA) Indexed Site

    2007-2015 Liquefied Natural Gas Prices -- -- -- -- -- -- 200

  7. U.S. LNG Imports from Equatorial Guinea

    U.S. Energy Information Administration (EIA) Indexed Site

    7-2015 Liquefied Natural Gas Prices -- -- -- -- -- -- 2007

  8. Central Equatorial Pacific Experiment (CEPEX)

    SciTech Connect (OSTI)

    Not Available

    1993-01-01

    The Earth's climate has varied significantly in the past, yet climate records reveal that in the tropics, sea surface temperatures seem to have been remarkably stable, varying by less than a few degrees Celsius over geologic time. Today, the large warm pool of the western Pacific shows similar characteristics. Its surface temperature always exceeds 27[degree]C, but never 31[degree]C. Heightened interest in this observation has been stimulated by questions of global climate change and the exploration of stabilizing climate feedback processes. Efforts to understand the observed weak sensitivity of tropical sea surface temperatures to climate forcing has led to a number of competing ideas about the nature of this apparent thermostat. Although there remains disagreement on the processes that regulate tropical sea surface temperature, most agree that further progress in resolving these differences requires comprehensive field observations of three-dimensional water vapor concentrations, solar and infrared radiative fluxes, surface fluxes of heat and water vapor, and cloud microphysical properties. This document describes the Central Equatorial Pacific Experiment (CEPEX) plan to collect such observations over the central equatorial Pacific Ocean during March of 1993.

  9. EQUATORIAL ZONAL JETS AND JUPITER's GRAVITY

    SciTech Connect (OSTI)

    Kong, D.; Liao, X.; Zhang, K.; Schubert, G.

    2014-08-20

    The depth of penetration of Jupiter's zonal winds into the planet's interior is unknown. A possible way to determine the depth is to measure the effects of the winds on the planet's high-order zonal gravitational coefficients, a task to be undertaken by the Juno spacecraft. It is shown here that the equatorial winds alone largely determine these coefficients which are nearly independent of the depth of the non-equatorial winds.

  10. ,"U.S. Liquefied Natural Gas Imports From Equatorial Guinea (MMcf)"

    U.S. Energy Information Administration (EIA) Indexed Site

    Annual",2015 ,"Release Date:","2/29/2016" ,"Next Release Date:","3/31/2016" ,"Excel File Name:","ngm_epg0_nus-nek_iml_mmcfa.xls" ,"Available from Web Page:","http://tonto.eia.gov/dnav/ng/hist/ngm_epg0_nus-nek_iml_mmcfa.htm" ,"Source:","Energy Information Administration" ,"For Help, Contact:","infoctr@eia.doe.gov" ,,"(202) 586-8800",,,"2/26/2016 2:52:02

  11. Price of U.S. Liquefied Natural Gas Imports From Equatorial Guinea...

    U.S. Energy Information Administration (EIA) Indexed Site

    Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 2000's 6.32 -- -- 2010's

  12. U.S. Liquefied Natural Gas Imports From Equatorial Guinea (Million...

    U.S. Energy Information Administration (EIA) Indexed Site

    Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2007 0 0 0 0 0 2,910 8,989 5,896 0 0 0 0 2008 0 0 0 0 0 0 0 0 0 0 0 0 2009 0 0 0 0 0 0 0 0 0 0 0 0 2010 0 0 0 0 0 0 0 0 0 0 0 0 ...

  13. Price of U.S. Liquefied Natural Gas Imports From Equatorial Guinea...

    U.S. Energy Information Administration (EIA) Indexed Site

    Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2007 -- -- -- -- -- 7.46 6.04 6.18 -- -- -- -- 2008 -- -- -- -- -- -- -- -- -- -- -- -- 2009 -- -- -- -- -- -- -- -- -- -- -- ...

  14. U.S. Liquefied Natural Gas Imports From Equatorial Guinea (Million...

    U.S. Energy Information Administration (EIA) Indexed Site

    Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 2000's 17,795 0 0 2010's

  15. Guinea: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Country Profile Name Guinea Population 10,628,972 GDP 5,212,000,000 Energy Consumption 0.02 Quadrillion Btu 2-letter ISO code GN 3-letter ISO code GIN Numeric ISO...

  16. Central Equatorial Pacific Experiment (CEPEX). Design document

    SciTech Connect (OSTI)

    Not Available

    1993-04-01

    The Earth`s climate has varied significantly in the past, yet climate records reveal that in the tropics, sea surface temperatures seem to have been remarkably stable, varying by less than a few degrees Celsius over geologic time. Today, the large warm pool of the western Pacific shows similar characteristics. Its surface temperature always exceeds 27{degree}C, but never 31{degree}C. Heightened interest in this observation has been stimulated by questions of global climate change and the exploration of stabilizing climate feedback processes. Efforts to understand the observed weak sensitivity of tropical sea surface temperatures to climate forcing has led to a number of competing ideas about the nature of this apparent thermostat. Although there remains disagreement on the processes that regulate tropical sea surface temperature, most agree that further progress in resolving these differences requires comprehensive field observations of three-dimensional water vapor concentrations, solar and infrared radiative fluxes, surface fluxes of heat and water vapor, and cloud microphysical properties. This document describes the Central Equatorial Pacific Experiment (CEPEX) plan to collect such observations over the central equatorial Pacific Ocean during March of 1993.

  17. Guinea-USAID Climate Activities | Open Energy Information

    Open Energy Info (EERE)

    International Development Sector Energy, Land Focus Area Renewable Energy, Forestry, Agriculture Topics Background analysis Website http:www.usaid.govourwork Country Guinea...

  18. Papua New Guinea Geothermal Region | Open Energy Information

    Open Energy Info (EERE)

    ENERGYGeothermal Home Papua New Guinea Geothermal Region Details Areas (1) Power Plants (1) Projects (0) Techniques (0) References Geothermal Region Data Area USGS Resource...

  19. Papua New Guinea Improved Energy Access for Rural Communities...

    Open Energy Info (EERE)

    Communities Location of project Papua New Guinea Energy Services Lighting, Cooking and water heating, Space heating, Cooling, Information and communications, Earning a living...

  20. Guinea-Bissau: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Country Profile Name Guinea-Bissau Population 1,345,479 GDP 870,000,000 Energy Consumption 0.01 Quadrillion Btu 2-letter ISO code GW 3-letter ISO code GNB Numeric ISO...

  1. Workbook Contents

    U.S. Energy Information Administration (EIA) Indexed Site

    Natural Gas Imports From Equatorial Guinea (MMcf)","U.S. Liquefied Natural Gas ... Natural Gas Imports From Equatorial Guinea (Dollars per Thousand Cubic Feet)","Price ...

  2. Workbook Contents

    U.S. Energy Information Administration (EIA) Indexed Site

    ... Gas Imports From Equatorial Guinea (Dollars per Thousand Cubic Feet)","Price of Elba Island, GA Natural Gas LNG Imports from Equatorial Guinea (Dollars per Thousand Cubic ...

  3. USAID West Africa Climate Program | Open Energy Information

    Open Energy Info (EERE)

    Guinea, Guinea-Bissau, Cameroon, Gabon, Equatorial Guinea, Chad, Sao Tome and Principe, Cape Verde Western Africa, Western Africa, Western Africa, Western Africa, Western...

  4. ,"Price of U.S. Liquefied Natural Gas Imports From Equatorial Guinea (Dollars per Thousand Cubic Feet)"

    U.S. Energy Information Administration (EIA) Indexed Site

    Annual",2015 ,"Release Date:","2/29/2016" ,"Next Release Date:","3/31/2016" ,"Excel File Name:","ngm_epg0_nus-nek_pml_dmcfa.xls" ,"Available from Web Page:","http://tonto.eia.gov/dnav/ng/hist/ngm_epg0_nus-nek_pml_dmcfa.htm" ,"Source:","Energy Information Administration" ,"For Help, Contact:","infoctr@eia.doe.gov" ,,"(202) 586-8800",,,"2/26/2016 2:52:03

  5. A Pilot Study of Uterine Artery Embolization with Tris-Acryl Gelatin Microspheres in Guinea Pigs

    SciTech Connect (OSTI)

    Zhuang Wenquan; Tan Guosheng; Guo Wenbo, E-mail: patrickguo2008@163.com [The First Affiliated Hospital of Sun Yat-sen University, Department of Interventional Radiology (China); Yang Jianyong [The First Affiliated Hospital of Sun Yat-sen University, Department of Radiology (China)

    2012-06-15

    Objective: This study was designed to establish guinea pigs as an animal model for uterine artery embolization (UAE) with tris-acryl gelatin microspheres (TAGM). Methods: Twenty-five female adult guinea pigs were randomly divided into two groups, including a uterine artery casting mould group (n = 10) and a UAE group (n = 15). Pelvic angiography and vascular casting mould were performed in the first group. The anatomical characters of the pelvic cavity in guinea pigs were described. In the second group, the technical feasibility of performing UAE with TAGM in guinea pigs was investigated. The histopathological slides of the uterus of guinea pigs after UAE were examined to inspect the outcomes of UAE. Results: The uterine artery springs from the internal iliac artery, ascends tortuously along the cervix, and gives off vertically 8-10 branches to the cervix uteri and uterine horns. The diameters of the trunk of the uterine artery and its first branch were 0.32 {+-} 0.027 mm and 0.14 {+-} 0.01 mm, respectively. For UAE animals, the dosages of 40-120 and 100-300 {mu}m TAGM were 0.033 {+-} 0.003 ml and 0.015 {+-} 0.002 ml, respectively. On histopathological slides, embosphere particles were found in the first branches of the uterine artery, the subserous arteries, and the intramural arteries. Inflammatory reactions in the uterus were common in guinea pigs after UAE. Local or dispersed areas of necrosis in uterus also were observed in a few guinea pigs. Conclusions: Guinea pigs are an appropriate and feasible model for UAE with TAGM.

  6. The ultraviolet photodissociation of axial and equatorial conformers of 3-pyrroline

    SciTech Connect (OSTI)

    Oliver, Thomas A. A.; King, Graeme A.; Ashfold, Michael N. R.

    2010-11-21

    Resolved sets of photoproducts arising from the photodissociation of axial and equatorial conformers of 3-pyrroline have been observed using H(Rydberg) atom photofragment translational spectroscopy following excitation in the wavelength range of 250-213 nm. 3-pyrroline (alternatively 2,5-dihydropyrrole) is a five membered partially saturated heterocycle in which the bonding around the N atom is pyramidal (sp{sup 3} hybridized) and the N-H bond can lie either axial or equatorial to the ring. Careful analysis of total kinetic energy release data derived from H atom time-of-flight measurements reveals excitation of the 3-pyrrolinyl cofragment consistent with N-H bond fission in both the axial and equatorial conformers. This allows determination of the energy difference between the ground state conformers to be 340{+-}50 cm{sup -1} and the N-H bond strength for axial and equatorial conformers as 31 610{+-}50 and 31 270{+-}50 cm{sup -1}, respectively.

  7. Sources and management of hazardous waste in Papua New Guinea

    SciTech Connect (OSTI)

    Singh, K.

    1996-12-31

    Papua New Guinea (PNG) has considerable mineral wealth, especially in gold and copper. Large-scale mining takes place, and these activities are the source of most of PNG`s hazardous waste. Most people live in small farming communities throughout the region. Those living adjacent to mining areas have experienced some negative impacts from river ecosystem damage and erosion of their lands. Industry is centered mainly in urban areas and Generates waste composed of various products. Agricultural products, pesticide residues, and chemicals used for preserving timber and other forestry products also produce hazardous waste. Most municipal waste comes from domestic and commercial premises; it consists mainly of combustibles, noncombustibles, and other wastes. Hospitals generate pathogenic organisms, radioactive materials, and chemical and pharmaceutical laboratory waste. Little is known about the actual treatment of waste before disposal in PNG. Traditional low-cost waste disposal methods are usually practiced, such as use of landfills; storage in surface impoundments; and disposal in public sewers, rivers, and the sea. Indiscriminate burning of domestic waste in backyards is also commonly practiced in urban and rural areas. 10 refs., 4 tabs.

  8. Protein A suppresses immune responses during Staphylococcus aureus bloodstream infection in guinea pigs

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

    Kim, Hwan Keun; Falugi, Fabiana; Thomer, Lena; Missiakas, Dominique M.; Schneewind, Olaf

    2015-01-06

    Staphylococcus aureus infection is not associated with the development of protective immunity, and disease relapses occur frequently. We hypothesize that protein A, a factor that binds immunoglobulin Fcγ and cross-links VH3 clan B cell receptors (IgM), is the staphylococcal determinant for host immune suppression. To test this, vertebrate IgM was examined for protein A cross-linking. High VH3 binding activity occurred with human and guinea immunoglobulin, whereas mouse and rabbit immunoglobulins displayed little and no binding, respectively. Establishing a guinea pig model of S. aureus bloodstream infection, we show that protein A functions as a virulence determinant and suppresses host Bmore » cell responses. Immunization with SpAKKAA, which cannot bind immunoglobulin, elicits neutralizing antibodies that enable guinea pigs to develop protective immunity.« less

  9. National Action Programmes on Desertification | Open Energy Informatio...

    Open Energy Info (EERE)

    Faso, Burundi, Cameroon, Cape Verde, Chad, Democratic Republic of Congo, Djibouti, Egypt, Equatorial Guinea, Eritrea, Ethiopia, Gabon, Gambia, Ghana, Guinea, Kenya, Lesotho,...

  10. Biomass resource potential for selected crops in Hawaii. [Koa haole (giant leucaena); napier and guinea grass

    SciTech Connect (OSTI)

    Seki, A.

    1982-06-01

    The biomass crops selected for review were koa haole (giant leucaena), napier and guinea grass, and eucalyptus (saligna, grandis, and globulus). The islands examined were Hawaii, Kauai, Maui, and Molokai. The potential land acreage for growing these crops was estimated grossly. As anticipated, the island of Hawaii had the largest land potential with eucalyptus having the greatest potential land acreage.

  11. POTENTIAL EVIDENCE FOR THE ONSET OF ALFVNIC TURBULENCE IN TRANS-EQUATORIAL CORONAL LOOPS

    SciTech Connect (OSTI)

    De Moortel, I.; Threlfall, J.; McIntosh, S. W.; Bethge, C.; Liu, J. E-mail: mscott@ucar.edu

    2014-02-20

    This study investigates Coronal Multi-channel Polarimeter Doppler-shift observations of a large, off-limb, trans-equatorial loop system observed on 2012 April 10-11. Doppler-shift oscillations with a broad range of frequencies are found to propagate along the loop with a speed of about 500kms{sup 1}. The power spectrum of perturbations travelling up from both loop footpoints is remarkably symmetric, probably due to the almost perfect north-south alignment of the loop system. Compared to the power spectrum at the footpoints of the loop, the Fourier power at the apex appears to be higher in the high-frequency part of the spectrum than expected from theoretical models. We suggest this excess high-frequency power could be tentative evidence for the onset of a cascade of the low-to-mid frequency waves into (Alfvnic) turbulence.

  12. Protein A suppresses immune responses during Staphylococcus aureus bloodstream infection in guinea pigs

    SciTech Connect (OSTI)

    Kim, Hwan Keun; Falugi, Fabiana; Thomer, Lena; Missiakas, Dominique M.; Schneewind, Olaf

    2015-01-06

    Staphylococcus aureus infection is not associated with the development of protective immunity, and disease relapses occur frequently. We hypothesize that protein A, a factor that binds immunoglobulin Fcγ and cross-links VH3 clan B cell receptors (IgM), is the staphylococcal determinant for host immune suppression. To test this, vertebrate IgM was examined for protein A cross-linking. High VH3 binding activity occurred with human and guinea immunoglobulin, whereas mouse and rabbit immunoglobulins displayed little and no binding, respectively. Establishing a guinea pig model of S. aureus bloodstream infection, we show that protein A functions as a virulence determinant and suppresses host B cell responses. Immunization with SpAKKAA, which cannot bind immunoglobulin, elicits neutralizing antibodies that enable guinea pigs to develop protective immunity.

  13. Potiguar basin: geologic model and habitat of oil of a Brazilian equatorial basin

    SciTech Connect (OSTI)

    Falkenhein, F.U.; Barros, R.M.; Da Costa, I.G.; Cainelli, C.

    1984-04-01

    The Potiguar basin integrates the eastern part of the Brazilian equatorial Atlantic-type margin. The rifting stage of this basin occurred during the Neocomian and Aptian. The drifting stage and sea-floor spreading began in the Late Albian. The rifting stage clearly was intracratonic during the Neocomian and is recognized as a mosaic of half-grabens trending mostly northeast-southwest and filled with syntectonic lacustrine siliciclastics. The half-graben pattern exhibits rotation of beds into the major fault zone, and the preserved uplifted margins display either paleostructures of paleogeomorphic features with hydrocarbons. A regional pre-Aptian unconformity preceded the Aptian proto-oceanic rifting stage which was characterized by syntectonic fluvio-deltaic sediments. The Aptian tectonics were represented by reactivation of former lineaments superimposed by predominant east-west normal faulting. Structural highs during this stage are so far the most prolific oil accumulations. The most important source beds and reservoir rocks are both Neocomian and Aptian sediments. Geochemistry and hydrodynamics have shown that hydrocarbon migration was driven through fracture or fault zones in both Aptian or Albian plays. Lithofacies maps support this interpretation because pools occur whenever adjacent downthrown blocks present a high shale content.

  14. Millimeter wave experiment of ITER equatorial EC launcher mock-up

    SciTech Connect (OSTI)

    Takahashi, K.; Oda, Y.; Kajiwara, K.; Kobayashi, N.; Isozaki, M.; Sakamoto, K.; Omori, T.; Henderson, M.

    2014-02-12

    The full-scale mock-up of the equatorial launcher was fabricated in basis of the baseline design to investigate the mm-wave propagation properties of the launcher, the manufacturability, the cooling line management, how to assemble the components and so on. The mock-up consists of one of three mm-wave transmission sets and one of eight waveguide lines can deliver the mm-wave power. The mock-up was connected to the ITER compatible transmission line and the 170GHz gyrotron and the high power experiment was carried out. The measured radiation pattern of the beam at the location of 2.5m away from the EL mock-up shows the successful steering capability of 20?40. It was also revealed that the radiated profile at both steering and fixed focusing mirror agreed with the calculation. The result also suggests that some unwanted modes are included in the radiated beam. Transmission of 0.5MW-0.4sec and of 0.12MW-50sec were also demonstrated.

  15. In vitro effects of fatty acids on goat, calf and guinea pig hepatic gluconeogenesis

    SciTech Connect (OSTI)

    Aiello, R.J.; Armentano, L.E.

    1986-03-05

    Isolated hepatocytes from male guinea pigs, ruminating goats and bull calves were incubated at 39 C for 1h. Fatty acids C18:1, C16, and C8 (.5, 1, 2 mM) were added as albumin complexes (3:1 molar ratio), C2 and C4 (1.25, 2.5 and 5 mM) were added as Na salts. In ruminant cells C2 had no effect on (2-/sup 14/C)-propionate (PROP) (2.5 mM) or (U-/sup 14/C)-L-lactate (LACT) (2.5 mM) metabolism. C4 (2.5 or 5 mM) decreased (/sup 14/C)-glucose (GLU) (P < .01) from PROP (48% goats, 68% calves) and decreased LACT conversion to GLU, (27% goats, 50% calves), C8, C16 and C18:1 effects depended on gluconeogenic substrate and species. In goat cells conversion of PROP to GLU was increased (P < .01) by C18:1 (30%) and C8 (52%) with C16 showing a similar trend. There were no interactions between the effects of fatty acids and lactation state (lactating does vs wethers). In goat cells C8 increased PROP conversion to GLU relative to oxidation, other fatty acids did not change relative rates. In calf cells C18:1, C16 and C8 had no effect on PROP metabolism. C8 inhibited gluconeogenesis from LACT in goats (24%) (P < .07) and calves (47%) (P < .01). In contrast fatty acids decreased (P < .01) GLU production from PROP (C18:1 90%, C8 80%) and LACT (C18:1 75%, C8 75%) in cells from guinea pigs. They have established a clear difference in the regulation of gluconeogenesis among species which contain similar intracellular distribution of P-enolpyruvate carboxykinase.

  16. Estimation of neutrophil infiltration into hairless guinea pig skin treated with 2,2' -dichlorodiethyl sulfide

    SciTech Connect (OSTI)

    Bongiovanni, R.; Millard, C.B.; Schulz, S.M.; Romano, J.M.

    1993-05-13

    Despite growing acceptance of the hairless guinea pig (HPG) for evaluating sulfur mustard (2,2'dichlorodiethylsulfide, HD) skin injury, there are presently few antivesicant drug assessment endpoints validated in vivo for this model. We measured the activity of myeloperoxidase (MPO) to characterize the dose- and time-dependence of polymorphonuclear leukocyte (PMN) infiltration during development of the HD lesion. Biopsies were obtained from the dorsal thoracic-lumbar area of HGPs at successive 3 hr time intervals for up to 24 hrs following controlled exposure to either 5, 7, 8 or 10 min HD vapor. The presence of PMNs, as judged by MPO levels, peaked at 9 hrs irrespective of total HD vapor dose. The maximum response was a 20-fold increase compared to unexposed control sites at 9 hrs following 10 min HD vapor. This time period coincides with epidermal detachment characterized previously by electron microscopy in the HGP. By 24 hrs post-exposure, the MPO levels subsided markedly (2-fold compared to controls). These results suggest that PMNs participate in the HGP cutaneous inflammatory response following exposure to HD and that MPO may be a useful biological marker for evaluating putative antivesicants.

  17. Three-dimensional structures of equatorial waves and the resulting super-rotation in the atmosphere of a tidally locked hot Jupiter

    SciTech Connect (OSTI)

    Tsai, Shang-Min; Gu, Pin-Gao; Dobbs-Dixon, Ian

    2014-10-01

    Three-dimensional (3D) equatorial trapped waves excited by stellar isolation and the resulting equatorial super-rotating jet in a vertical stratified atmosphere of a tidally locked hot Jupiter are investigated. Taking the hot Jupiter HD 189733b as a fiducial example, we analytically solve linear equations subject to stationary stellar heating with a uniform zonal-mean flow included. We also extract wave information in the final equilibrium state of the atmosphere from our radiative hydrodynamical simulation for HD 189733b. Our analytic wave solutions are able to qualitatively explain the 3D simulation results. Apart from previous wave studies, investigating the vertical structure of waves allows us to explore new wave features such as the wavefronts tilts related to the Rossby-wave resonance as well as dispersive equatorial waves. We also attempt to apply our linear wave analysis to explain some numerical features associated with the equatorial jet development seen in the general circulation model by Showman and Polvani. During the spin-up phase of the equatorial jet, the acceleration of the jet can be in principle boosted by the Rossby-wave resonance. However, we also find that as the jet speed increases, the Rossby-wave structure shifts eastward, while the Kelvin-wave structure remains approximately stationary, leading to the decline of the acceleration rate. Our analytic model of jet evolution implies that there exists only one stable equilibrium state of the atmosphere, possibly implying that the final state of the atmosphere is independent of initial conditions in the linear regime. Limitations of our linear model and future improvements are also discussed.

  18. Mast cells in citric acid-induced cough of guinea pigs

    SciTech Connect (OSTI)

    Lai, Y.-L. . E-mail: tiger@ha.mc.ntu.edu.tw; Lin, T.-Y.

    2005-01-01

    It was demonstrated previously that mast cells play an important role in citric acid (CA)-induced airway constriction. To investigate the role of mast cells in CA-induced cough, three experiments were carried out in this study. In the first experiment, 59 guinea pigs were employed and we used compound 48/80 to deplete mast cells, cromolyn sodium to stabilize mast cells, MK-886 to inhibit leukotriene synthesis, pyrilamine to antagonize histamine H{sub 1} receptor, methysergide to antagonize serotonin receptor, and indomethacin to inhibit cyclooxygenase. In the second experiment, 56 compound 48/80-pretreated animals were divided into two parts; the first one was used to test the role of exogenous leukotriene (LT) C{sub 4}, while the second one to test the role of exogenous histamine in CA-induced cough. Each animal with one of the above pretreatments was exposed sequentially to saline (baseline) and CA (0.6 M) aerosol, each for 3 min. Then, cough was recorded for 12 min using a barometric body plethysmograph. In the third experiment, the activation of mast cells upon CA inhalation was investigated by determining arterial plasma histamine concentration in 17 animals. Exposure to CA induced a marked increase in cough number. Compound 48/80, cromolyn sodium, MK-886 and pyrilamine, but not indomethacin or methysergide, significantly attenuated CA-induced cough. Injection of LTC{sub 4} or histamine caused a significant increase in CA-induced cough in compound 48/80-pretreated animals. In addition, CA inhalation caused significant increase in plasma histamine concentration, which was blocked by compound 48/80 pretreatment. These results suggest that mast cells play an important role in CA aerosol inhalation-induced cough via perhaps mediators LTs and histamine.

  19. --No Title--

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    Cyprus Czech Republic Denmark Djibouti Dominica Dominican Republic Ecuador Egypt El Salvador Equatorial Guinea Eritrea Estonia Ethiopia Falkland Islands (Islas Malvinas) Faroe...

  20. 14655 Section I

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

    Czech Republic Poland Denmark Portugal Djibouti Rwanda Equatorial Guinea Sao Tome and Principe Estonia Sierra Leone Finland Singapore France Slovak Republic Gambia Slovenia Germany...

  1. U.S.-Africa Energy Ministerial Co-Chairs' Summary from Energy...

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

    the Democratic Republic of the Congo, the Republic of Djibouti, the Arab Republic of Egypt, the Republic of Equatorial Guinea, the Gabonese Republic, the Republic of the Gambia,...

  2. Natural Gas Weekly Update, Printer-Friendly Version

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    or 75 percent of all deliveries. In recent years, several African countries, including Egypt, Equatorial Guinea, Nigeria, and Algeria, also have been suppliers of LNG to the...

  3. DOE - Fossil Energy:

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

    States. The United States imports natural gas from Canada, Mexico, Algeria, Australia, Egypt, Equatorial Guinea, Malaysia, Nigeria, Norway, Oman, Qatar, Trinidad and Tobago, and...

  4. Matt Schatzman € Houston € 22 October 2007

    U.S. Energy Information Administration (EIA) Indexed Site

    ... US as the balancing market in action 11 US as part of the global marketplace Algeria Australia Egypt Equatorial Guinea Malaysia Nigeria Trinidad & Tobago Oman Qatar Belgium Japan ...

  5. State of lithospheric stress and borehole stability at Deep Sea Drilling Project site 504B, eastern equatorial Pacific

    SciTech Connect (OSTI)

    Morin, R.H. ); Newmark, R.L. ); Barton, C.A. ); Anderson, R.N. )

    1990-06-10

    Hole 504B in the eastern equatorial Pacific is the deepest hole to penetrate oceanic basement, extending more than 1,500 m beneath the seafloor. Two borehole televiewer (BHTV) logs have been combined and processed in terms of both acoustic amplitude and travel time in order to evaluate the extent and distribution of rock failure along the borehole wall. A histogram of borehole enlargements versus azimuth depicts a dominant breakout azimuth of N122.5{degree}E which corresponds to the direction of minimum principal stress S{sub h}. Furthermore, the bimodality of this histogram, with a secondary mode orthogonal to S{sub h}, indicates that a significant number of enlargements are coalesced tensile fractures occurring along the orientation of S{sub H}, the maximum principal stress. The appearance of this orthogonal, bimodal distribution suggests that the regional horizontal stress field is highly anisotropic, a condition supported by seismic data. The frequency of borehole enlargements increases with increasing depth and depicts a systematic structural deterioration of the well bore. The tensile fractures along the S{sub H} azimuth contribute to this degradation and appear to be induced by thermal stresses due to the injection of cold water into hot rock. The frequency of these extensional features does not increase with depth. Rather, their appearances can be directly correlated with shipboard efforts at deliberately cooling the well and/or with the sudden resumption of drilling after the hole had been allowed to reequilibrate thermally for several days. These latter borehole enlargements are more pronounced than those commonly associated with hydraulic fracturing. The mechanism for fracture initiation and growth, based upon temperature contrasts between the well bore fluid and the adjacent rock may enhance rock failure.

  6. Ascorbic acid suppresses endotoxemia and NF-?B signaling cascade in alcoholic liver fibrosis in guinea pigs: A mechanistic approach

    SciTech Connect (OSTI)

    Abhilash, P.A.; Harikrishnan, R.; Indira, M.

    2014-01-15

    Alcohol consumption increases the small intestinal bacterial overgrowth (SIBO) and intestinal permeability of endotoxin. The endotoxin mediated inflammatory signaling plays a major role in alcoholic liver fibrosis. We evaluated the effect of ascorbic acid (AA), silymarin and alcohol abstention on the alcohol induced endotoxemia and NF-?B activation cascade pathway in guinea pigs (Cavia porcellus). Guinea pigs were administered ethanol at a daily dose of 4 g/kg b.wt for 90 days. After 90 days, ethanol administration was stopped. The ethanol treated animals were divided into abstention, silymarin (250 mg/kg b.wt) and AA (250 mg/kg b.wt) supplemented groups and maintained for 30 days. The SIBO, intestinal permeability and endotoxin were significantly increased in the ethanol group. The mRNA expressions of intestinal proteins claudin, occludin and zona occludens-1 were significantly decreased in ethanol group. The mRNA levels of inflammatory receptors, activity of IKK? and the protein expressions of phospho-I?B?, NF-?B, TNF-?, TGF-?{sub 1} and IL-6 were also altered in ethanol group. The expressions of fibrosis markers ?-SMA, ?{sub 1} (I) collagen and sirius red staining in the liver revealed the induction of fibrosis. But the supplementation of AA could induce greater reduction of ethanol induced SIBO, intestinal barrier defects, NF-?B activation and liver fibrosis than silymarin. The possible mechanism may be the inhibitory effect of AA on SIBO, intestinal barrier defect and IKK?, which decreased the activation of NF-?B and synthesis of cytokines. This might have led to suppression of HSCs activation and liver fibrosis. - Highlights: Alcohol increases intestinal bacterial overgrowth and permeability of endotoxin. Endotoxin mediated inflammation plays a major role in alcoholic liver fibrosis. Ascorbic acid reduces endotoxemia, NF-?B activation and proinflammatory cytokines. AA's action is by inhibition of SIBO, IKK? and alteration of intestinal permeability. This might have led to suppression of HSCs activation and liver fibrosis.

  7. Reduction of erythema in hairless guinea pigs after cutaneous sulfur mustard vapor exposure by pretreatment with niacinamide, promethazine and indomethacin

    SciTech Connect (OSTI)

    Yourick, J.J.; Dawson, J.S.; Mitcheltree, L.W.

    1995-12-31

    Erythema is the initial symptom that occurs after sulfur mustard (HD) cutaneous exposure. The time course of HD-induced erythema is similar to that observed after UV irradiation, which can be reduced by indomethacin. Sulfur mustard lethality is decreased by using promethazine, which is an antihistamine. Niacinamide can reduce microvesication after HD vapor exposure in hairless guinea pig (HGP) skin. The present study examines the effect of the combined administration of niacinamide, indomethacin and promethazine used alone or in all possible combinations on the degree of erythema and histopathologic skin damage after HD exposure in HGP. Niacinamide (750 mg kg%`, i.p.), promethazine (12.5 mg kg%1, i.m.) or indomethacin (4 mg kg%1, p.o.) used singly or in combination was given as a 30-min pretreatment before an 8-min HD vapor cup skin exposure. Using a combination pretreatment of niacinamide, promethazine and indomethacin, erythema was reduced at 4 (91%) and 6 (55%) h, but not 24 h after HD. The incidence of histopathological skin changes (microvesicles, follicular involvement, epidermal necrosis, intracellular edema and pustular epidermatitis) 24 h after HD was not reduced. This study indicates that HD (induced erythema) may result from several different mechanisms, including inflammation, histamine release and DNA damage. It is suggested that two phases of inflammation may occur: an early phase sensitive to antihistamines and non-steroidal antiinflammatory drugs and a late phase of extensive cell damage that was not sensitive to these drug pretreatments.

  8. Cutaneous uptake of 14C-HD vapor by the hairless guinea pig. Technical report, December 1992-June 1993

    SciTech Connect (OSTI)

    Logan, T.P.; Bongiovanni, R.; Millard, C.B.; Shutz, M.B.; Schultz, S.M.

    1996-10-01

    The hairless guinea pig (HGP) is used by our laboratory to model the human cutaneous response to sulfur mustard (HD) exposure. We have determined the HD content in the skin of HOP after 7-minute exposures to vapors saturated with a mixture of HD and 14C-HD. Concentration/time (C1) values in the range of 2 mg/sq cm/min were determined by counting skin 14C disintegrations per minute (dpm) in animals euthanized immediately after exposure. These values are similar to human penetration rates obtained by other investigators. A direct relationship between C1 and relative humidity was demonstrated in 5 of 6 studies. A rate curve monitoring the reduction in skin 14C dpm was developed for animals euthanized between 0 and 24 hours post exposure. This curve showed the greatest change after 1 hour. Epidermal and dermal distribution of 14C at 24 hours was measured for two animals. Site preference for HD penetration, multiple use of a vapor cap containing HD, and 14C content of adhesive tape were also investigated with radiolabeled HD to evaluate other aspects of the experimental model. These results contribute to a better understanding of the cutaneous response to HD in the HGP model.

  9. A critical evaluation of the upper ocean heat budget in the Climate Forecast System Reanalysis data for the south central equatorial Pacific

    SciTech Connect (OSTI)

    Liu H.; Lin W.; Liu, X.; Zhang, M.

    2011-08-26

    Coupled ocean-atmospheric models suffer from the common bias of a spurious rain belt south of the central equatorial Pacific throughout the year. Observational constraints on key processes responsible for this bias are scarce. The recently available reanalysis from a coupled model system for the National Centers for Environmental Prediction (NCEP) Climate Forecast System Reanalysis (CFSR) data is a potential benchmark for climate models in this region. Its suitability for model evaluation and validation, however, needs to be established. This paper examines the mixed layer heat budget and the ocean surface currents - key factors for the sea surface temperature control in the double Inter-Tropical Convergence Zone in the central Pacific - from 5{sup o}S to 10{sup o}S and 170{sup o}E to 150{sup o}W. Two independent approaches are used. The first approach is through comparison of CFSR data with collocated station observations from field experiments; the second is through the residual analysis of the heat budget of the mixed layer. We show that the CFSR overestimates the net surface flux in this region by 23 W m{sup -2}. The overestimated net surface flux is mainly due to an even larger overestimation of shortwave radiation by 44 W m{sup -2}, which is compensated by a surface latent heat flux overestimated by 14 W m{sup -2}. However, the quality of surface currents and the associated oceanic heat transport in CFSR are not compromised by the surface flux biases, and they agree with the best available estimates. The uncertainties of the observational data from field experiments are also briefly discussed in the present study.

  10. Workbook Contents

    U.S. Energy Information Administration (EIA) Indexed Site

    Natural Gas Imports From Canada (MMcf)","U.S. Liquefied Natural Gas Imports From Egypt (MMcf)","U.S. Liquefied Natural Gas Imports From Equatorial Guinea (MMcf)","U.S....

  11. User:GregZiebold/Developing Country Programs Map | Open Energy...

    Open Energy Info (EERE)

    of Congo 12 Djibouti 3 Dominica 9 Dominican Republic 12 Ecuador 7 Egypt 14 El Salvador 8 Equatorial Guinea 4 Eritrea 3 Estonia 2 Ethiopia 21 Fiji 1 Gabon 10 ... further...

  12. DOE - Fossil Energy:

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

    of Equatorial Guinea BG LNG Services, LLC 2288 FE06-05-LNG 010606 Arab Republic of Egypt BG LNG Services, LLC 2287 FE06-04-LNG 010606 Trinidad and Tobago BG LNG Services,...

  13. ,"U.S. Crude Oil Imports"

    U.S. Energy Information Administration (EIA) Indexed Site

    Imports from Denmark of Crude Oil (Thousand Barrels per Day)","U.S. Imports from Egypt of Crude Oil (Thousand Barrels per Day)","U.S. Imports from Equatorial Guinea of Crude...

  14. U.S. Crude Oil Imports

    U.S. Energy Information Administration (EIA) Indexed Site

    (Brazzaville) 24 8 13 20 12 15 1993-2015 Congo (Kinshasa) 1993-2013 Denmark 1997-2004 Egypt 17 1993-2015 Equatorial Guinea 1996-2014 Estonia 1999-1999 Gabon 4 18 1993-2015...

  15. ,"U.S. Crude Oil Imports"

    U.S. Energy Information Administration (EIA) Indexed Site

    Imports from Denmark of Crude Oil (Thousand Barrels)","U.S. Imports from Egypt of Crude Oil (Thousand Barrels)","U.S. Imports from Equatorial Guinea of Crude Oil...

  16. Workbook Contents

    U.S. Energy Information Administration (EIA) Indexed Site

    of Crude Oil (Thousand Barrels per Day)","Weekly U.S. Imports from Equatorial Guinea of Crude Oil (Thousand Barrels per Day)","Weekly U.S. Imports from Norway of Crude Oil ...

  17. Equatorial hydrology studies by satellite telemetry

    SciTech Connect (OSTI)

    Clegg, B.; Koranda, J.; Robison, W.; Holladay, G.

    1980-12-30

    We are using a geostationary satellite functioning as a transponder to collect surface environmental data to describe the fate of soil-borne radionuclides. The remote, former atomic testing grounds at the Enewetak and Bikini Atolls present a difficult environment in which to collect continuous field data. Our land-based, solar-powered microprocessor and environmental data systems remotely measure net and total solar radiation, rain, humidity, temperature, and soil-water potentials. For the past year, our water-flux model predicted wet season plant-transpiration rates nearly equal to the 6- to 7-mm/d evaporation-pan rate, which decreases to 2 to 3 mm/d for the dry season. From the microclimate data we estimated a 1:3 and 1:20 /sup 137/Cs dry-matter concentration ratio, which was later confirmed by radioisotopic analysis. This ratio exacerbates the dose to man from intake of food plants. Nephelometer measurements of airborne particulates presently indicate a minimum respiratory radiological dose.

  18. Turmoil doesn`t dampen enthusiasm

    SciTech Connect (OSTI)

    1997-08-01

    The paper discusses the outlook for the African gas and oil industries. Though Africa remains politically and economically volatile, its vast energy potential is becoming increasingly attractive to foreign oil and gas companies. Separate evaluations are given for Algeria, Egypt, Nigeria, Angola, Libya, Congo, Gabon, Tunisia, Cameroon, Cote D`Ivoire, and briefly for South Africa, Sudan, Equatorial Guinea, Ghana, Zaire, Benin, Mozambique, Chad, Namibia, Tanzania, Eritrea, Guinea-Bissau, Senegal, Morocco, Sao Tome and Principe, Ethiopia, Niger, Madagascar, Rwanda, Mauritania, Seychelles, Uganda, and Liberia.

  19. Comparative behavior of plutonium and americium in the equatorial Pacific

    SciTech Connect (OSTI)

    Noshkin, V.E.; Wong, K.M.; Jokela, T.A.; Brunk, J.L.; Eagle, R.J.

    1983-01-01

    Inventories of /sup 239 +240/Pu and /sup 241/Am greatly in excess of global fallout levels persist in the benthic environments of Bikini and Enewetak Atolls. The amount of /sup 239 +240/Pu mobilized to solution at the atolls can be predicted from a distribution coefficient K/sub d/ of 2.3 x 10/sup 5/ and the mean sediment concentrations. The mobilized /sup 239 +240/Pu has solute-like characteristics and different valence states coexist in solution - the largest fraction of the soluble plutonium is in an oxidized form (+V,VI). The adsorption of plutonium to sediments is not completely reversible because of changes that occur in the relative amounts of the mixed oxidation states in solution with time. Characteristics of /sup 239 +240/Pu described at one location may not necessarily describe its behavior elsewhere. The relative amounts of /sup 241/Am to /sup 239 +240/Pu may be altered in future years because of mobilization and radiological decay.

  20. Papua New Guinea-Lowering Emissions in Asia's Forests (LEAF)...

    Open Energy Info (EERE)

    assessing, improving, and implementing REDD+- related forest policies; improving forest management; and encouraging equitable sharing of REDD+ benefits. The program will tailor...

  1. Papua New Guinea: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    EIA Natural Gas Reserves 226,500,000,000 Cubic Meters (cu m) 44 2010 CIA World Factbook Oil Reserves 170,000,000 Barrels (bbl) 62 2010 CIA World Factbook Energy Maps featuring...

  2. Papua New Guinea-Pilot Program for Climate Resilience (PPCR)...

    Open Energy Info (EERE)

    Development (IISD) Sector Climate, Energy, Land, Water Focus Area Renewable Energy, Agriculture, Biomass, - Waste to Energy, Economic Development, Forestry, Greenhouse...

  3. Papua New Guinea-Low Emissions Asian Development (LEAD) Program...

    Open Energy Info (EERE)

    the growth of greenhouse gas emissions. The LEAD program supports and enhances country-led development programs, plans, and policies, and complements efforts of other...

  4. Guinea-Bissau: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    0 Area(km) Class 3-7 Wind at 50m 116 1990 NREL Solar Potential 93,662,158 MWhyear 132 2008 NREL Coal Reserves Unavailable Million Short Tons NA 2008 EIA Natural Gas...

  5. Tropical Africa: Land Use, Biomass, and Carbon Estimates for 1980 (NDP-055)

    SciTech Connect (OSTI)

    Brown, S.

    2002-04-16

    This document describes the contents of a digital database containing maximum potential aboveground biomass, land use, and estimated biomass and carbon data for 1980. The biomass data and carbon estimates are associated with woody vegetation in Tropical Africa. These data were collected to reduce the uncertainty associated with estimating historical releases of carbon from land use change. Tropical Africa is defined here as encompassing 22.7 x 10{sup 6} km{sup 2} of the earth's land surface and is comprised of countries that are located in tropical Africa (Angola, Botswana, Burundi, Cameroon, Cape Verde, Central African Republic, Chad, Congo, Benin, Equatorial Guinea, Ethiopia, Djibouti, Gabon, Gambia, Ghana, Guinea, Ivory Coast, Kenya, Liberia, Madagascar, Malawi, Mali, Mauritania, Mozambique, Namibia, Niger, Nigeria, Guinea-Bissau, Zimbabwe (Rhodesia), Rwanda, Senegal, Sierra Leone, Somalia, Sudan, Tanzania, Togo, Uganda, Burkina Faso (Upper Volta), Zaire, and Zambia). The database was developed using the GRID module in the ARC/INFO{trademark} geographic information system. Source data were obtained from the Food and Agriculture Organization (FAO), the U.S. National Geophysical Data Center, and a limited number of biomass-carbon density case studies. These data were used to derive the maximum potential and actual (ca. 1980) aboveground biomass values at regional and country levels. The land-use data provided were derived from a vegetation map originally produced for the FAO by the International Institute of Vegetation Mapping, Toulouse, France.

  6. Oil and gas developments in central and southern Africa in 1987

    SciTech Connect (OSTI)

    Hartman, J.B.; Walker, T.L.

    1988-10-01

    Significant rightholding changes took place in central and southern Africa during 1987. Angola, Benin, Congo, Gabon, Ghana, Guinea, Guinea Bissau, Mauritania, Seychelles, Somali Republic, Tanzania, Zaire, and Zambia announced awards or acreage open for bidding. Decreases in exploratory rightholdings occurred in Cameroon, Congo, Cote d'Ivoire, Equatorial Guinea, Gabon, Kenya, Namibia, South Africa, and Tanzania. More wells and greater footage were drilled in 1987 than in 1986. Total wells increased by 18% as 254 wells were completed compared to 217 in 1986. Footage drilled during the year increased by 46% as about 1.9 million ft were drilled compared to about 1.3 million ft in 1986. The success rate for exploration wells in 1987 improved slightly to 36% compared to 34% in 1986. Significant discoveries were made in Nigeria, Angola, Congo, and Gabon. Seismic acquisition in 1987 was the major geophysical activity during the year. Total oil production in 1987 was 773 million bbl (about 2.1 million b/d), a decrease of 7%. The decrease is mostly due to a 14% drop in Nigerian production, which comprises 60% of total regional production. The production share of OPEC countries (Nigeria and Gabon) versus non-OPEC countries of 67% remained unchanged from 1986. 24 figs., 5 tabs.

  7. Papua New Guinea-ClimateWorks Low Carbon Growth Planning Support...

    Open Energy Info (EERE)

    Organization ClimateWorks, Project Catalyst, McKinsey and Company Sector Energy, Land Topics Background analysis, Low emission development planning, Policiesdeployment...

  8. Africa: the emphasis is exploration

    SciTech Connect (OSTI)

    Not Available

    1980-08-15

    Individual country reports on drilling, oil and gas production, and petroleum exploration and reserves are given for Africa. Nigeria was the continent's largest oil producer in 1979, averaging 2.3 million bpd, followed closely by Libya with 2.07 million bpd. Algeria cut production of crude oil in 1979 to a level of 1,194,350 bpd, and increased gas production to 2031 mmcfd. In Egypt, the return of Israeli-occupied oil fields and a surge in productive capacity enabled production averaging 524,000 bpd. Brief country reports are included for Gabon, Angola, Republic of the Congo, Cameroun, Tunisia, Morocco, Zaire, Ivory Coast, Ghana, Niger, Chad, Republic of South Africa, Sudan, Tanzania, Equatorial Guinea, Seychelles Islands, Mauritania, Republic of Mali, Benin, Kenya, Madagascar, Botswana, Gambia, Mozambique, and Senegal.

  9. U.S. Liquefied Natural Gas Imports by Point of Entry

    U.S. Energy Information Administration (EIA) Indexed Site

    7,173 11,205 5,654 8,689 7,515 5,618 1997-2015 From Canada 41 44 45 43 45 59 2013-2015 Portal, ND 1 0 2015-2015 Champlain, NY 1 2 1 2 20 2014-2015 Sumas, WA 4 4 2 1 2014-2015 Highgate Springs, VT 41 39 40 41 43 37 2013-2015 From Algeria 0 0 0 0 0 0 1973-2015 From Australia 0 0 0 0 0 0 1973-2015 From Brunei 0 0 0 0 0 0 2001-2015 From Egypt 0 0 0 0 0 0 2005-2015 Cameron, LA 2011-2011 Elba Island, GA 2011-2012 Freeport, TX 2011-2011 Gulf LNG, MS 2011-2011 From Equatorial Guinea 0 0 0 0 0 0

  10. The Gut Microbiota of Rural Papua New Guineans: Composition,...

    Office of Scientific and Technical Information (OSTI)

    regions in Papua New Guinea (PNG) with that of United States (US) residents. ... Woods Hole, MA (United States) Papua New Guinea Inst. of Medical Research, Goroka, ...

  11. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    ... sciences fecal microbiota (1) papua new guinea (1) Filter by Author Eren, A. Murat (1) ... regions in Papua New Guinea (PNG) with that of United States (US) residents. ...

  12. The evolution of 1 AU equatorial solar wind and its association with the morphology of the heliospheric current sheet from solar cycles 23 to 24

    SciTech Connect (OSTI)

    Zhao, L.; Landi, E.; Zurbuchen, T. H.; Fisk, L. A.; Lepri, S. T.

    2014-09-20

    The solar wind can be categorized into three types based on its 'freeze-in' temperature (T {sub freeze-in}) in the coronal source: low T {sub freeze-in} wind mostly from coronal holes, high T {sub freeze-in} wind mostly from regions outside of coronal holes, including streamers (helmet streamer and pseudostreamer), active regions, etc., and transient interplanetary coronal mass ejections (ICMEs) usually possessing the hottest T {sub freeze-in}. The global distribution of these three types of wind has been investigated by examining the most effective T {sub freeze-in} indicator, the O{sup 7+}/O{sup 6+} ratio, as measured by the Solar Wind Ion Composition Spectrometer on board the Advanced Composition Explorer (ACE) during 1998-2008 by Zhao et al. In this study, we extend the previous investigation to 2011 June, covering the unusual solar minimum between solar cycles 23 and 24 (2007-2010) and the beginning of solar cycle 24. We find that during the entire solar cycle, from the ascending phase of cycle 23 in 1998 to the ascending phase of cycle 24 in 2011, the average fractions of the low O{sup 7+}/O{sup 6+} ratio (LOR) wind, the high O{sup 7+}/O{sup 6+} ratio (HOR) wind, and ICMEs at 1 AU are 50.3%, 39.4%, and 10.3%, respectively; the contributions of the three types of wind evolve with time in very different ways. In addition, we compare the evolution of the HOR wind with two heliospheric current sheet (HCS) parameters, which indicate the latitudinal standard deviation (SD) and the slope (SL) of the HCS on the synoptic Carrington maps at 2.5 solar radii surface. We find that the fraction of HOR wind correlates with SD and SL very well (slightly better with SL than with SD), especially after 2005. This result verifies the link between the production of HOR wind and the morphology of the HCS, implying that at least one of the major sources of the HOR wind must be associated with the HCS.

  13. U.S. Fuel Ethanol (Renewable) Imports

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    Jul-15 Aug-15 Sep-15 Oct-15 Nov-15 Dec-15 View History All Countries 41 367 505 213 498 228 1993-2015 Ecuador 2007-2007 Non OPEC* 41 367 505 213 498 228 2004-2015 Argentina 2006-2006 Belgium 2012-2012 Brazil 32 361 498 209 492 223 2004-2015 Canada 9 6 7 4 6 5 2004-2015 China 2006-2006 Congo (Brazzaville) 2006-2006 Costa Rica 2004-2013 El Salvador 2004-2013 Guatemala 2012-2014 Jamaica 2004-2013 Netherlands 2006-2014 Nicaragua 2012-2014 Pakistan 2006-2006 Singapore 2014-2014 Trinidad and Tobago

  14. Category:Economic Community of West African States | Open Energy...

    Open Energy Info (EERE)

    15 pages are in this category, out of 15 total. B Benin Burkina Faso C Cape Verde G Gambia Ghana G cont. Guinea Guinea-Bissau I Ivory Coast L Liberia M Mali N Niger Nigeria...

  15. Alternative Fuels Data Center: Maps and Data

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    idle-reduction Go Generated_thumb20141209-960-mjqcb8 Clean Cities Petroleum Savings by Idle Reduction Generated_thumb20141209-960-mjqcb8 Trend of displacement by idle reduction policies and technologies from 2004-2013 Last update December 2014 View Graph Graph Download Data 10568_vehicle_idle_20130906 Estimated Fuel Used by Commercial Trucks While Idling 10568_vehicle_idle_20130906 Comparison of idling percentage for different commercial trucks. Last update September 2013 View Graph Graph

  16. Lihir Geothermal Power Plant | Open Energy Information

    Open Energy Info (EERE)

    Lihir Geothermal Power Plant General Information Name Lihir Geothermal Power Plant Sector Geothermal energy Location Information Location Lihir Island, Papua New Guinea Coordinates...

  17. ARM - TWP Manus Site-Inactive

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

    Western Pacific locale was established. The Manus facility was located at Momote Airport on Los Negros Island in Manus Province, Papua New Guinea (PNG). This location was...

  18. TWP Manus Site

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

    Western Pacific locale was established. The Manus facility was located at Momote Airport on Los Negros Island in Manus Province, Papua New Guinea (PNG). This location was...

  19. ARM - Facility News Article

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

    data at five ARM sites: Barrow, Alaska; Lamont, Oklahoma; Darwin, Australia; Manus, Papa New Guinea; and Nauru Island. In addition to bringing ARM the MMCR, Ken is also...

  20. --No Title--

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

    Nicaragua Niger Nigeria Niue Norway Oman Pakistan Palestine Panama Papua New Guinea Paraguay Peru Philippines Poland Portugal Puerto Rico Qatar Reunion Romania Russia Rwanda...

  1. Category:Countries | Open Energy Information

    Open Energy Info (EERE)

    Korea Northern Mariana Islands Norway O Oman P Pakistan Palau Panama Papua New Guinea Paraguay Peru Philippines Pitcairn Poland Portugal Puerto Rico Q Qatar R Republic of Macedonia...

  2. Stump the Scientist Question Form | GE Global Research

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

    Norway Northern Mariana Islands Oman Pakistan Palau Palestine Panama Papua New Guinea Paraguay Peru Philippines Poland Portugal Puerto Rico Qatar Romania Russia Rwanda Saint Kitts...

  3. Utility Rate Database | Open Energy Information

    Open Energy Info (EERE)

    Islands Norway Oman Pakistan Palau Palestinian Territories Panama Papua New Guinea Paraguay Peru Philippines Pitcairn Islands Poland Portugal Puerto Rico Qatar Romania Russia...

  4. Forest Carbon Partnership Facility | Open Energy Information

    Open Energy Info (EERE)

    Madagascar, Mexico, Moldova, Mozambique, Nepal, Nicaragua, Panama, Papua New Guinea, Paraguay, Peru, Republic of the Congo, Suriname, Tanzania, Thailand, Uganda, Vanuatu, Vietnam...

  5. Substrate-Induced Band-Gap Opening in Epitaxial Graphene

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

    Technology), D.-H. Lee (University of California, Berkeley), F. Guinea (Instituto de Ciencia de Materiales de Madrid, Spain), and A.H. Castro Neto (Boston University). Research...

  6. ARM - Publications: Science Team Meeting Documents

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

    New Guinea and Republic of Nauru, the TWP Office has developed stable power and reliable communications systems to continuously operate an extensive suite of in-situ instruments,...

  7. US ITER is a strong contributor in plan to enhance international...

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

    systems that will be installed on the ITER tokamak. Gallery: Diagram of an equatorial port plug shows the three vertical diagnostic shield modules with detachable first wall...

  8. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    ... instability that occurs can only result in equatorial mass loss. less January 1984 Grain growth in the turbulent accretion disk solar nebula Mizuno, H. The present ...

  9. Audio-Magnetotellurics | Open Energy Information

    Open Energy Info (EERE)

    natural source predominantly resulting from equatorial lightning discharge as the signal for the MT measurement. The typical period range for an AMT survey is 0.0001...

  10. SREL Reprint #3203

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

    I. Lehr Brisbin Jr.2, Mark Feinstein3, and Susan Bulmer4 1The New Guinea Singing Dog Conservation Society, 5265 Old Stage Road, Central Point, Oregon 97502, USA 2Savannah...

  11. Posters

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

    ... westward flow of the SEC, the southward Ekman drift and coastal currents off New Guinea. ... Finally, the eastern Indian Ocean (region I) receives the largest net surface heat flux ...

  12. From: Audrea Keninger To: Congestion Study Comments Subject:

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

    ... I also do not appreciate that I and my family, get to be the guinea pigs to see if this line has any health risks. It is already a safety hazard that we would have to endure even ...

  13. Bluer Skies and Brighter Days: The U.S. and India Collaborate...

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

    ... That information is plugged into the data streams from ARM's permanent field sites that are located across the globe - from Alaska and Oklahoma to Australia and Papua New Guinea. ...

  14. Evidence for a Weak Iron Core at Earth's Center

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

    Evidence for a Weak Iron Core at Earth's Center Print Seismic waves that pass through the center of the Earth travel faster going from pole to pole than along the equatorial...

  15. Research Highlight

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

    Exp and (c) CAM3 Ctrl over the central and eastern equatorial Pacific (150E-110W, 5S-5N). Each point represents a monthly mean value over a CAM3 grid point. The large red...

  16. Evidence for a Weak Iron Core at Earth's Center

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

    going from pole to pole than along the equatorial plane-why? One theory is that the grains of iron that make up most of the solid inner core could be aligned in a way that...

  17. Evidence for a Weak Iron Core at Earth's Center

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

    Iron Core at Earth's Center Print Seismic waves that pass through the center of the Earth travel faster going from pole to pole than along the equatorial plane-why? One theory...

  18. ARM MJO Investigation Experiment on

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

    ... 620-638. Masumoto, Y, H Hase, Y Kuroda, H Matsuura, and K Takeuchi. 2005. "Intraseasonal variability in the upper layer currents observed in the eastern equatorial Indian Ocean." ...

  19. Research Highlight

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

    Journal Reference: Long CN, SA McFarlane, A Del Genio, P Minnis, TP Ackerman, J Mather, J Comstock, GG Mace, M Jensen, and C Jakob. 2013. "ARM research in the equatorial western ...

  20. 1

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

    18, 1130-1143. Platt, C. M. R., S. A. Young, P. J. Manson, G. R. Patterson, S. C. Marsden, R. T. Austin, and J. Churnside, 1998: The optical properties of equatorial cirrus...

  1. ARM - Feature Stories and Releases Article

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

    January 23, 2015 [Feature Stories and Releases] Chasing Aerosols and Atmospheric Rivers Bookmark and Share ARM Cloud Aerosol Precipitation Experiment (ACAPEX) sets sail and takes flight An atmospheric river branches off an equatorial storm, stretching from Hawaii to the U.S. West Coast, transporting as much moisture as 10-20 times the flow in the Mississippi River. An atmospheric river branches off an equatorial storm, stretching from Hawaii to the U.S. West Coast, transporting as much moisture

  2. Thermal shallow water models of geostrophic turbulence in Jovian atmospheres

    SciTech Connect (OSTI)

    Warneford, Emma S. Dellar, Paul J.

    2014-01-15

    Conventional shallow water theory successfully reproduces many key features of the Jovian atmosphere: a mixture of coherent vortices and stable, large-scale, zonal jets whose amplitude decreases with distance from the equator. However, both freely decaying and forced-dissipative simulations of the shallow water equations in Jovian parameter regimes invariably yield retrograde equatorial jets, while Jupiter itself has a strong prograde equatorial jet. Simulations by Scott and Polvani [Equatorial superrotation in shallow atmospheres, Geophys. Res. Lett. 35, L24202 (2008)] have produced prograde equatorial jets through the addition of a model for radiative relaxation in the shallow water height equation. However, their model does not conserve mass or momentum in the active layer, and produces mid-latitude jets much weaker than the equatorial jet. We present the thermal shallow water equations as an alternative model for Jovian atmospheres. These equations permit horizontal variations in the thermodynamic properties of the fluid within the active layer. We incorporate a radiative relaxation term in the separate temperature equation, leaving the mass and momentum conservation equations untouched. Simulations of this model in the Jovian regime yield a strong prograde equatorial jet, and larger amplitude mid-latitude jets than the Scott and Polvani model. For both models, the slope of the non-zonal energy spectra is consistent with the classic Kolmogorov scaling, and the slope of the zonal energy spectra is consistent with the much steeper spectrum observed for Jupiter. We also perform simulations of the thermal shallow water equations for Neptunian parameter values, with a radiative relaxation time scale calculated for the same 25 mbar pressure level we used for Jupiter. These Neptunian simulations reproduce the broad, retrograde equatorial jet and prograde mid-latitude jets seen in observations. The much longer radiative time scale for the colder planet Neptune explains the transition from a prograde to a retrograde equatorial jet, while the broader jets are due to the deformation radius being a larger fraction of the planetary radius.

  3. Webinar: Overview of the Hydrogen Fueling Infrastructure Research...

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

    ... The last thing we want to do is put impure fuel into a vehicle. We don't want to use the vehicle as a guinea pig. So this is important. Sort of the two sub-tasks within this are ...

  4. Understanding the El Niño-like Oceanic Response in the Tropical Pacific to Global Warming

    SciTech Connect (OSTI)

    Luo, Yiyong; Lu, Jian; Liu, Fukai; Liu, Wei

    2015-10-10

    The enhanced central and eastern Pacific SST warming and the associated ocean processes under global warming are investigated using the ocean component of the Community Earth System Model (CESM), Parallel Ocean Program version 2 (POP2). The tropical SST warming pattern in the coupled CESM can be faithfully reproduced by the POP2 forced with surface fluxes computed using the aerodynamic bulk formula. By prescribing the wind stress and/or wind speed through the bulk formula, the effects of wind stress change and/or the wind-evaporation-SST (WES) feedback are isolated and their linearity is evaluated in this ocean-alone setting. Result shows that, although the weakening of the equatorial easterlies contributes positively to the El Niño-like SST warming, 80% of which can be simulated by the POP2 without considering the effects of wind change in both mechanical and thermodynamic fluxes. This result points to the importance of the air-sea thermal interaction and the relative feebleness of the ocean dynamical process in the El Niño-like equatorial Pacific SST response to global warming. On the other hand, the wind stress change is found to play a dominant role in the oceanic response in the tropical Pacific, accounting for most of the changes in the equatorial ocean current system and thermal structures, including the weakening of the surface westward currents, the enhancement of the near-surface stratification and the shoaling of the equatorial thermocline. Interestingly, greenhouse gas warming in the absence of wind stress change and WES feedback also contributes substantially to the changes at the subsurface equatorial Pacific. Further, this warming impact can be largely replicated by an idealized ocean experiment forced by a uniform surface heat flux, whereby, arguably, a purest form of oceanic dynamical thermostat is revealed.

  5. The problem of living in a world contaminated with chemicals

    SciTech Connect (OSTI)

    Metcalf, R.L.

    1990-12-31

    The proliferation of xenobiotic chemicals in the global environment poses living problems for each of us aboard {open_quotes}spaceship earth.{close_quotes} Seven case studies are presented that illustrate the magnitude of the problem that can result from waiting to identify toxic hazards until there have been decades of {open_quotes}human guinea pig{close_quotes} exposure. 25 refs., 5 tabs.

  6. ARM - Events Article

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

    April 8, 2013 [Events, Facility News] ARM Facility Highlights at EGU General Assembly 2013 Bookmark and Share Where do scientists get their data? The Atmospheric Radiation Measurement (ARM) Climate Research Facility provides continuous data from heavily instrumented fixed sites in the United States (Alaska and Oklahoma), the Tropical Pacific (Australia and Papua New Guinea), and soon in the Azores. These measurements are supplemented through mobile observation facilities and research aircraft at

  7. ARM - Visiting the TWP

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

    InactiveVisiting the TWP TWP Related Links Facilities and Instruments Manus Island Nauru Island Darwin, AUS ES&H Guidance Statement Operations Science Field Campaigns Year of Tropical Convection Visiting the Site TWP Fact Sheet Images Information for Guest Scientists Contacts Visiting the TWP Nauru Island from the air. Nauru Island from the air. The Tropical Western Pacific site consists of three diverse climate research facilities in Papua New Guinea, the Republic of Nauru, and Australia.

  8. ARM - Who's Teacher Turtle?

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

    Teacher Turtle? Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans Who's Teacher Turtle? Teacher Turtle lives in the toasty tropical waters, referred to as the Pacific "warm pool," off the coast of Papua New Guinea, just north of Australia. She is one of eight species of sea turtles

  9. In-service packet with pics.pmd

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

    Climate Change Into The Classroom ARM Education Program North Slope of Alaska 2002 What is ARM? What is ARM Education? The Atmospheric Radiation Measurement Program (here, "radiation" means sunlight and radiant heat) is the largest global climate change research program supported by the U.S. Department of Energy. The ARM Program has data collecting sites in three very different places in the world: the Tropical Western Pacific (Australia, Papua New Guinea, and Nauru), in the Southern

  10. Nonlinear electron acceleration by oblique whistler waves: Landau resonance vs. cyclotron resonance

    SciTech Connect (OSTI)

    Artemyev, A. V.; Agapitov, O. V.; Krasnoselskikh, V. V.; Mourenas, D.

    2013-12-15

    This paper is devoted to the study of the nonlinear interaction of relativistic electrons and high amplitude strongly oblique whistler waves in the Earth's radiation belts. We consider electron trapping into Landau and fundamental cyclotron resonances in a simplified model of dipolar magnetic field. Trapping into the Landau resonance corresponds to a decrease of electron equatorial pitch-angles, while trapping into the first cyclotron resonance increases electron equatorial pitch-angles. For 100 keV electrons, the energy gained due to trapping is similar for both resonances. For electrons with smaller energy, acceleration is more effective when considering the Landau resonance. Moreover, trapping into the Landau resonance is accessible for a wider range of initial pitch-angles and initial energies in comparison with the fundamental resonance. Thus, we can conclude that for intense and strongly oblique waves propagating in the quasi-electrostatic mode, the Landau resonance is generally more important than the fundamental one.

  11. STOIC: An Assessment of Coupled Model Climatology and Variability in Tropical Ocean Regions

    SciTech Connect (OSTI)

    Davey, M.K.; Sperber, K.R.; Huddleston, M

    2000-08-30

    The tropics are regions of strong ocean-atmosphere interaction on seasonal and interannual timescales, so a good representation of observed tropical behavior is a desirable objective for coupled ocean-atmosphere general circulation models (CGCMs). To broaden and update previous assessments (Mechoso et al. 1995, Neelin et al. 1992), two complementary projects were initiated by the CLIVAR Working Group on Seasonal to Interannual Prediction (WGSIP): the El Nino Simulation Intercomparison Project (ENSIP, by Mojib Latif) and STOIC (Study of Tropical Oceans In Coupled models). The aim was to compare models against observations to identify common weaknesses and strengths. Results from ENSIP concentrating on the equatorial Pacific have been described by Latif et al. (2000), hereafter ENSIP2000. A detailed report on STOIC is available via anonymous ftp at email.meto.gov.uk/pub/cr/ ''stoic'' and is summarized in Davey et al. (2000). The STOIC analyses extend beyond the equatorial Pacific, to examine behavior in all three tropical ocean regions.

  12. Visible wide angle view imaging system of KTM tokamak based on multielement image fiber bundle

    SciTech Connect (OSTI)

    Chektybayev, B. Shapovalov, G.; Kolodeshnikov, A.

    2015-05-15

    In the paper, new visible wide angle view imaging system of KTM tokamak is described. The system has been designed to observe processes inside of plasma and the processes occurring due to plasma-wall interactions through the long equatorial port. Imaging system is designed based on special image fiber bundle and entrance wide angle lens, which provide image of large section of the vacuum chamber, both poloidal half-section and divertor through the sufficiently long equatorial port. The system also consists of two video cameras: slow and fast with image intensifier. Commercial equipment had been used in design of the system that allowed reducing the cost and time for research and development. The paper also discusses advantages and disadvantages of the system in comparison with conventional endoscopes based on a lens system and considers its promising utilization in future tokamaks and future steady state fusion reactors.

  13. Measurements of Spatial Line Emission Profiles in the Main Scrape-Off Layer of the DIII-D Tokamak

    SciTech Connect (OSTI)

    Groth, M; Ellis, R; Brooks, N; Fenstermacher, M; Lasnier, C; Meyer, W; Moller, J

    2009-06-05

    A video camera system is described that measures the spatial distribution of visible line emission emitted from the main scrape-off layer (SOL) of plasmas in the DIII-D tokamak. A wide-angle lens installed on an equatorial port and an in-vessel mirror which intercepts part of the lens view provide simultaneous tangential views of the SOL on the low-field and high-field sides of the plasma's equatorial plane. Tomographic reconstruction techniques are used to calculate the 2-D poloidal profiles from the raw data, and 1-D poloidal profiles simulating chordal views of other optical diagnostics from the 2-D profiles. The 2-D profiles can be compared with SOL plasma simulations; the 1-D profiles with measurements from spectroscopic diagnostics. Sample results are presented which elucidate carbon transport in plasmas with toroidally uniform injection of methane and argon transport in disruption mitigation experiments with massive gas jet injection.

  14. ARM - Publications: Science Team Meeting Documents

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

    Tropical Cloud Radiative Forcing and the Large-Scale Atmospheric Energy Transport Tian, B. (a) and Ramanathan, V. (b), Scripps Institution of Oceanography, UCSD Eleventh Atmospheric Radiation Measurement (ARM) Science Team Meeting Moist static energy is exported within the atmosphere column, from equatorial latitudes to the subtropics by the Hadley circulation and from the western Pacific warm pool to the eastern Pacific cold tongue by the Walker circulation. It is the net energy fluxes into the

  15. hare-98.pdf

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

    Diurnal Variability of Turbulent Fluxes in the Equatorial Pacific J. E. Hare Cooperative Institute for Research in Environmental Sciences University of Colorado Boulder, Colorado C. W. Fairall NOAA-Environmental Technology Laboratory Boulder, Colorado Introduction During March and April of 1996, scientists from 13 national research institutions participated in the Combined Sensor Program (CSP) experiment. This program is a collaborative effort of the U.S. Department of Energy (DOE) and the

  16. The global climate for December 1990-February 1991: Strong temperature and precipitation contrasts over North America and Eurasia; mixed ENSO conditions in the tropics

    SciTech Connect (OSTI)

    Chelliah, M. )

    1993-07-01

    During most of the December 1990-February 1991 season sharp transcontinental temperature anomaly contrasts were evident in North America, Eurasia, and Australia. Large-scale atmospheric precipitations are more difficult to characterize. In the equatorial tropics there was some evidence of conditions similar to ENSO near the date line, but an almost complete failure of other ENSO components to appear in the east Pacific and in the tropical atmospheric circulation. 12 refs., 21 figs., 1 tab.

  17. Applications of pulsed EPR spectroscopy to structural studies of sulfite oxidizing enzymes

    SciTech Connect (OSTI)

    Klein, Eric L.; Astashkin, Andrei V.; Raitsimring, Arnold; Enemark, John H.

    2013-01-01

    Sulfite oxidizing enzymes (SOEs), including sulfite oxidase (SO) and bacterial sulfite dehydrogenase (SDH), catalyze the oxidation of sulfite (SO32?) to sulfate (SO42?). The active sites of SO and SDH are nearly identical, each having a 5-coordinate, pseudo-square-pyramidal Mo with an axial oxo ligand and three equatorial sulfur donor atoms. One sulfur is from a conserved Cys residue and two are from a pyranopterindithiolene (molybdopterin, MPT) cofactor. The identity of the remaining equatorial ligand, which is solvent-exposed, varies during the catalytic cycle. Numerous in vitro studies, particularly those involving electron paramagnetic resonance (EPR) spectroscopy of the Mo(V) states of SOEs, have shown that the identity and orientation of this exchangeable equatorial ligand depends on the buffer pH, the presence and concentration of certain anions in the buffer, as well as specific point mutations in the protein. Until very recently, however, EPR has not been a practical technique for directly probing specific structures in which the solvent-exposed, exchangeable ligand is an O, OH?, H2O, SO32?, or SO42? group, because the primary O and S isotopes (16O and 32S) are magnetically silent (I = 0). This review focuses on the recent advances in the use of isotopic labeling, variable-frequency high resolution pulsed EPR spectroscopy, synthetic model compounds, and DFT calculations to elucidate the roles of various anions, point mutations, and steric factors in the formation, stabilization, and transformation of SOE active site structures.

  18. Ventilatory function assessment in safety pharmacology: Optimization of rodent studies using normocapnic or hypercapnic conditions

    SciTech Connect (OSTI)

    Goineau, Sonia; Rompion, Sonia; Guillaume, Philippe; Picard, Sandra

    2010-09-15

    Although the whole body plethysmography for unrestrained animals is the most widely used method to assess the respiratory risk of new drugs in safety pharmacology, non-appropriate experimental conditions may mask deleterious side effects of some substances. If stimulant or bronchodilatory effects can be easily evidenced in rodents under standard experimental conditions, i.e. normal air breathing and diurnal phase, drug-induced respiratory depression remains more difficult to detect. This study was aimed at comparing the responsiveness of Wistar rats, Duncan Hartley guinea-pigs or BALB/c mice to the respiratory properties of theophylline (50 or 100 mg/kg p.o.) or morphine (30 mg/kg i.p.) under varying conditions (100% air versus 5% CO{sub 2}-enriched air, light versus dark day phase), in order to select the most appropriate experimental conditions to each species for safety airway investigations. Our results showed that under normocapnia the ventilatory depressant effects of morphine can be easily evidenced in mice, slightly observed in guinea-pigs and not detected in rats in any day phase. Slight hypercapnic conditions enhanced the responsiveness of rats to morphine but not that of guinea-pigs and importantly they did not blunt the airway responsiveness of rats to the stimulation and bronchodilation evoked by theophylline, the most widely used reference agent in safety pharmacology studies. In conclusion, hypercapnic conditions associated with the non-invasive whole body plethysmography should be considered for optimizing the assessment of both the ventilatory depressant potential of morphine-like substances or the respiratory stimulant effects of new drugs in the rat, the most extensively used species in rodent safety and toxicological investigations.

  19. Annual review of earth and planetary sciences. Vol. 19

    SciTech Connect (OSTI)

    Wetherill, G.W.; Albee, A.L.; Burke, K.C. (Carnegie Inst. of Washington, DC (United States) California Inst. of Tech., Pasadena (United States) National Research Council, Washington, DC (United States))

    1991-01-01

    Various review papers on earth and planetary sciences are presented. The individual topics addressed include: tectonics of the New Guinea area, interpretation of ancient Eolian and dunes, seismic tomography of the earth's mantle, shock modification and chemistry and planetary geologic processes, the significance of evaporites, the magnetosphere, untangling the effects of burial alteration and ancient soil formation. Also discussed are: pressure-temperature-time paths, fractals in rock physics, earthquake prediction, rings in the ocean, applications of Be{minus}10 to problems in the earth sciences, measurement of crustal deformation using the GPS, physics and physical mechanisms of nuclear winter, experiemental determination of bed-form stability.

  20. 1

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

    Tropical Western Pacific (TWP) site is next to the Pacific "warm pool" - off the coast of Papua New Guinea, just north of Australia. The "warm pool" is important because it gives off heat and moisture to the atmosphere above it, forming deep convective cloud systems. These cloud systems control the amount of solar energy that reaches the earth's surface and the amount of the earth's heat energy that can escape into space. The TWP site has locations in Manus, Nauru, and

  1. Options for developing countries in mining development

    SciTech Connect (OSTI)

    Walrond, G.W.; Kumar, R.

    1985-01-01

    This book is a study of the issues that developing countries face in planning and implementing mineral development, taking as case studies Botswana, Sierra Leone, Zambia, Tanzania, Malaysia, Papua New Guinea and the developed states of Quebec and Western Australia. The authors consider the major aspects of the matter including organization and administration; regulation; taxation and surplus distribution; the dynamics of such instruments as royalty, rent resource tax and capital allowances under various cost/price scenarios; and selected mining agreements and their key provisions. They stress throughout the need for foreign investment while maximizing the economic benefits reaped from exhaustible resources.

  2. mather-98.pdf

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

    3 Analyses of Measurements for the First Year of Operation of the Tropical Western Pacific Atmospheric Radiation and Cloud Station J. H. Mather and T. P. Ackerman Department of Meteorology The Pennsylvania State University University Park, Pennsylvania Introduction The first Tropical Western Pacific Atmospheric Radiation and Cloud Station (TWP ARCS) has been operating since October 1996. The TWP ARCS is located on the island of Los Negros, Manus Province, Papua New Guinea, at 2.06°S, 147.42°E.

  3. Non-OPEC oil supply continues to grow

    SciTech Connect (OSTI)

    Knapp, D.H.

    1995-12-25

    Global reserves of crude oil remain at 1 trillion bbl, according to OGJ`s annual survey of producing countries. Significant gains are in Brazil, Colombia, Congo, Egypt, Libya, Nigeria, Oman, and Papua New Guinea. Decreases were reported by Indonesia, Norway, the U.K., Iran, Canada, Mexico, and the US. Natural gas reserves slipped to 4.9 quadrillion cu ft. The major production trend is a lasting surge from outside of OPEC. This year`s Worldwide Production report begins with a detailed analysis of this crucial development by an international authority. This article discusses the OECD outlook by region and the turnaround in production in the former Soviet Union.

  4. ARM - Feature Stories and Releases Article

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

    , 2011 [Feature Stories and Releases] AMIE, What You Wanna Do? Bookmark and Share Data spanning the Maldives to Papua New Guinea will help scientists analyze far-reaching tropical weather cycle This view shows a subset of the ARM Mobile Facility instruments operating at the Gan Island airport for the AMIE campaign. To see the complete collection, see the image set in Flickr. This view shows a subset of the ARM Mobile Facility instruments operating at the Gan Island airport for the AMIE campaign.

  5. Tropical Western Pacific

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

    govSitesTropical Western Pacific TWP Related Links Facilities and Instruments Manus Island Nauru Island Darwin, AUS ES&H Guidance Statement Operations Science Field Campaigns Year of Tropical Convection Visiting the Site TWP Fact Sheet Images Information for Guest Scientists Contacts Tropical Western Pacific-Inactive Manus, Papua New Guinea: 2° 3' 39.64" S, 147° 25' 31.43" E Nauru Island: 0° 31' 15.6" S, 166° 54' 57.60" E Darwin, Australia: 12° 25' 28.56" S,

  6. Chimeric human parainfluenza virus bearing the Ebola virus glycoprotein as the sole surface protein is immunogenic and highly protective against Ebola virus challenge

    SciTech Connect (OSTI)

    Bukreyev, Alexander Marzi, Andrea; Feldmann, Friederike; Zhang Liqun; Dorward, David W.; Pickles, Raymond J.; Feldmann, Heinz; Collins, Peter L.

    2009-01-20

    We generated a new live-attenuated vaccine against Ebola virus (EBOV) based on a chimeric virus HPIV3/{delta}F-HN/EboGP that contains the EBOV glycoprotein (GP) as the sole transmembrane envelope protein combined with the internal proteins of human parainfluenza virus type 3 (HPIV3). Electron microscopy analysis of the virus particles showed that they have an envelope and surface spikes resembling those of EBOV and a particle size and shape resembling those of HPIV3. When HPIV3/{delta}F-HN/EboGP was inoculated via apical surface of an in vitro model of human ciliated airway epithelium, the virus was released from the apical surface; when applied to basolateral surface, the virus infected basolateral cells but did not spread through the tissue. Following intranasal (IN) inoculation of guinea pigs, scattered infected cells were detected in the lungs by immunohistochemistry, but infectious HPIV3/{delta}F-HN/EboGP could not be recovered from the lungs, blood, or other tissues. Despite the attenuation, the virus was highly immunogenic, and a single IN dose completely protected the animals against a highly lethal intraperitoneal challenge of guinea pig-adapted EBOV.

  7. Correlated Pc4-5 ULF waves, whistler-mode chorus, and pulsating aurora observed by the Van Allen Probes and ground-based systems

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

    Jaynes, A. N.; Lessard, M. R.; Takahashi, K.; Ali, A. F.; Malaspina, D. M.; Michell, R. G.; Spanswick, E. L.; Baker, D. N.; Blake, J. B.; Cully, C.; et al

    2015-10-28

    Theory and observations have linked equatorial VLF waves with pulsating aurora for decades, invoking the process of pitch angle scattering of tens of keV electrons in the equatorial magnetosphere. Recently published satellite studies have strengthened this argument, by showing strong correlation between pulsating auroral patches and both lower-band chorus and tens of keV electron modulation in the vicinity of geosynchronous orbit. Additionally, a previous link has been made between Pc4–5 compressional pulsations and modulation of whistler-mode chorus using Time History of Events and Macroscale Interactions during Substorms. In the current study, we present simultaneous in situ observations of structured chorusmore » waves and an apparent field line resonance (in the Pc4–5 range) as a result of a substorm injection, observed by Van Allen Probes, along with ground-based observations of pulsating aurora. We demonstrate the likely scenario being one of substorm-driven Pc4–5 ULF pulsations modulating chorus waves, and thus providing the driver for pulsating particle precipitation into the Earth's atmosphere. Interestingly, the modulated chorus wave and ULF wave periods are well correlated, with chorus occurring at half the periodicity of the ULF waves. We also show, for the first time, a particular few-Hz modulation of individual chorus elements that coincides with the same modulation in a nearby pulsating aurora patch. As a result, such modulation has been noticed as a high-frequency component in ground-based camera data of pulsating aurora for decades and may be a result of nonlinear chorus wave interactions in the equatorial region.« less

  8. String loops in the field of braneworld spherically symmetric black holes and naked singularities

    SciTech Connect (OSTI)

    Stuchlk, Z.; Kolo, M. E-mail: martin.kolos@fpf.slu.cz

    2012-10-01

    We study motion of current-carrying string loops in the field of braneworld spherically symmetric black holes and naked singularities. The spacetime is described by the Reissner-Nordstrm geometry with tidal charge b reflecting the non-local tidal effects coming from the external dimension; both positive and negative values of the spacetime parameter b are considered. We restrict attention to the axisymmetric motion of string loops when the motion can be fully governed by an appropriately defined effective potential related to the energy and angular momentum of the string loops. In dependence on these two constants of the motion, the string loops can be captured, trapped, or can escape to infinity. In close vicinity of stable equilibrium points at the centre of trapped states the motion is regular. We describe how it is transformed to chaotic motion with growing energy of the string loop. In the field of naked singularities the trapped states located off the equatorial plane of the system exist and trajectories unable to cross the equatorial plane occur, contrary to the trajectories in the field of black holes where crossing the equatorial plane is always admitted. We concentrate our attention to the so called transmutation effect when the string loops are accelerated in the deep gravitational field near the black hole or naked singularity by transforming the oscillatory energy to the energy of the transitional motion. We demonstrate that the influence of the tidal charge can be substantial especially in the naked singularity spacetimes with b > 1 where the acceleration to ultrarelativistic velocities with Lorentz factor ? ? 100 can be reached, being more than one order higher in comparison with those obtained in the black hole spacetimes.

  9. Miocene-Early Pliocene diatomaceous sedimentation patterns in the Pacific: A response to paleooceanography and paleoclimatic change

    SciTech Connect (OSTI)

    Barron, J.A. )

    1990-05-01

    Biosiliceous sediments greatly expanded their distribution in the North Pacific during the late early to early middle Miocene (18-15 Ma), at least partly due to enhanced basin-basin fractionation of deep waters between the North Atlantic and North Pacific, which began in 17 Ma. Subsequently, in the late middle and late Miocene, diatomaceous sedimentation responded to the following series of successive cooling steps. (1) High-latitude cooling between 14.9 and 12.4 Ma caused an intensification of upwelling in the marginal North Pacific as evidenced by a wider distribution of laminated sediments and a decline in carbonate preservation. (2) Cooling across the middle Miocene-late Miocene boundary (10.3-9.2 Ma and 9.0-8.3 Ma) led to further increases in upwelling and raised biogenic opal accumulation rates in upwelling regions of the eastern equatorial Pacific, California, and Peru. (3) Cooling in the latest Miocene to earliest Pliocene (6.2-4.8 114a) resulted in further regional differentiation of biosiliceous sedimentation patterns in the North Pacific, probably reflecting steeper productivity gradients in upwelling regions. Biogenic opal accumulation rates declined in the eastern equatorial Pacific, but probably increased in coastal upwelling regions off California, Peru, and in the Bering Sea. (4) A decline in diatom sedimentation in waters off southern California during the earliest Pliocene (4.5-4.0) Ma coincided with a period of warmer paleotemperatures and a decline in opal accumulation rates in the equatorial Pacific. A major increase in biosiliceous sedimentation in the Southern ocean occurred at this same time.

  10. THE DARK ENERGY SURVEY: PROSPECTS FOR RESOLVED STELLAR POPULATIONS

    SciTech Connect (OSTI)

    Rossetto, Bruno M.; Santiago, Baslio X.; Girardi, Lo; Camargo, Julio I. B.; Balbinot, Eduardo; da Costa, Luiz N.; Yanny, Brian; Maia, Marcio A. G.; Makler, Martin; Ogando, Ricardo L. C.; Pellegrini, Paulo S.; Ramos, Beatriz; de Simoni, Fernando; Armstrong, R.; Bertin, E.; Desai, S.; Kuropatkin, N.; Lin, H.; Mohr, J. J.; Tucker, D. L.

    2011-06-01

    Wide angle and deep surveys, regardless of their primary purpose, always sample a large number of stars in the Galaxy and in its satellite system. We here make a forecast of the expected stellar sample resulting from the Dark Energy Survey and the perspectives that it will open for studies of Galactic structure and resolved stellar populations in general. An estimated 1.2 x 108 stars will be sampled in DES grizY filters in the southern equatorial hemisphere. This roughly corresponds to 20% of all DES sources. Most of these stars belong to the stellar thick disk and halo of the Galaxy.

  11. THE DARK ENERGY SURVEY: PROSPECTS FOR RESOLVED STELLAR POPULATIONS

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

    Rossetto, Bruno M.; Santiago, Baslio X.; Girardi, Lo; Camargo, Julio I. B.; Balbinot, Eduardo; da Costa, Luiz N.; Yanny, Brian; Maia, Marcio A. G.; Makler, Martin; Ogando, Ricardo L. C.; et al

    2011-06-01

    Wide angle and deep surveys, regardless of their primary purpose, always sample a large number of stars in the Galaxy and in its satellite system. We here make a forecast of the expected stellar sample resulting from the Dark Energy Survey and the perspectives that it will open for studies of Galactic structure and resolved stellar populations in general. An estimated 1.2 x 108 stars will be sampled in DES grizY filters in the southern equatorial hemisphere. This roughly corresponds to 20% of all DES sources. Most of these stars belong to the stellar thick disk and halo of themoreGalaxy.less

  12. Electromagnetic Analysis For The Design Of ITER Diagnostic Port Plugs During Plasma Disruptions

    SciTech Connect (OSTI)

    Zhai, Y

    2014-03-03

    ITER diagnostic port plugs perform many functions including structural support of diagnostic systems under high electromagnetic loads while allowing for diagnostic access to plasma. The design of diagnotic equatorial port plugs (EPP) are largely driven by electromagnetic loads and associate response of EPP structure during plasma disruptions and VDEs. This paper summarizes results of transient electromagnetic analysis using Opera 3d in support of the design activities for ITER diagnostic EPP. A complete distribution of disruption loads on the Diagnostic First Walls (DFWs). Diagnostic Shield Modules (DSMs) and the EPP structure, as well as impact on the system design integration due to electrical contact among various EPP structural components are discussed.

  13. mitrescu-c revised

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

    1 LIRAD Analysis of Equatorial Cirrus at the TWP (Manus Island and Nauru) CART Sites C. Mitrescu, R. T. Austin, C.M.R. Platt, and G. L. Stephens Colorado State University Fort Collins, Colorado Introduction The purpose of this work is to obtain high-cloud emittance and optical depth over the Tropical Western Pacific (TWP) (Manus Island and Nauru) Cloud and Radiation Testbed (CART) sites on a routine basis using the lidar/radiometer (LIRAD) method. Current operation of the micropulse lidar

  14. Evidence for a Weak Iron Core at Earth's Center

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

    Evidence for a Weak Iron Core at Earth's Center Print Seismic waves that pass through the center of the Earth travel faster going from pole to pole than along the equatorial plane-why? One theory is that the grains of iron that make up most of the solid inner core could be aligned in a way that transmits waves more efficiently in one direction than the other. Recent evidence for this "texturing" of iron grains in the Earth's inner core comes from x-ray spectroscopy and diffraction

  15. Evidence for a Weak Iron Core at Earth's Center

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

    Evidence for a Weak Iron Core at Earth's Center Print Seismic waves that pass through the center of the Earth travel faster going from pole to pole than along the equatorial plane-why? One theory is that the grains of iron that make up most of the solid inner core could be aligned in a way that transmits waves more efficiently in one direction than the other. Recent evidence for this "texturing" of iron grains in the Earth's inner core comes from x-ray spectroscopy and diffraction

  16. Evidence for a Weak Iron Core at Earth's Center

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

    Evidence for a Weak Iron Core at Earth's Center Print Seismic waves that pass through the center of the Earth travel faster going from pole to pole than along the equatorial plane-why? One theory is that the grains of iron that make up most of the solid inner core could be aligned in a way that transmits waves more efficiently in one direction than the other. Recent evidence for this "texturing" of iron grains in the Earth's inner core comes from x-ray spectroscopy and diffraction

  17. Evidence for a Weak Iron Core at Earth's Center

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

    Evidence for a Weak Iron Core at Earth's Center Print Seismic waves that pass through the center of the Earth travel faster going from pole to pole than along the equatorial plane-why? One theory is that the grains of iron that make up most of the solid inner core could be aligned in a way that transmits waves more efficiently in one direction than the other. Recent evidence for this "texturing" of iron grains in the Earth's inner core comes from x-ray spectroscopy and diffraction

  18. Evidence for a Weak Iron Core at Earth's Center

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

    Evidence for a Weak Iron Core at Earth's Center Print Seismic waves that pass through the center of the Earth travel faster going from pole to pole than along the equatorial plane-why? One theory is that the grains of iron that make up most of the solid inner core could be aligned in a way that transmits waves more efficiently in one direction than the other. Recent evidence for this "texturing" of iron grains in the Earth's inner core comes from x-ray spectroscopy and diffraction

  19. Evidence for a Weak Iron Core at Earth's Center

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

    Evidence for a Weak Iron Core at Earth's Center Print Seismic waves that pass through the center of the Earth travel faster going from pole to pole than along the equatorial plane-why? One theory is that the grains of iron that make up most of the solid inner core could be aligned in a way that transmits waves more efficiently in one direction than the other. Recent evidence for this "texturing" of iron grains in the Earth's inner core comes from x-ray spectroscopy and diffraction

  20. Evidence for a Weak Iron Core at Earth's Center

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

    Evidence for a Weak Iron Core at Earth's Center Evidence for a Weak Iron Core at Earth's Center Print Wednesday, 30 April 2014 00:00 Seismic waves that pass through the center of the Earth travel faster going from pole to pole than along the equatorial plane-why? One theory is that the grains of iron that make up most of the solid inner core could be aligned in a way that transmits waves more efficiently in one direction than the other. Recent evidence for this "texturing" of iron

  1. High-pressure cells for in situ multi-anvil experiments

    SciTech Connect (OSTI)

    Leinenweber, K.; Mosenfelder, J.; Diedrich, T.; Soignard, E.; Sharp, T.G.; Tyburczy, J.A.; Wang, Y.

    2008-10-14

    A new series of high-pressure cells for in situ multi-anvil experiments is described. The cells are based on the conventional COMPRES cells, but modifications are made to improve the passage of X-rays. The modifications include cutting slits in parts of the assemblies that have very high X-ray absorption, such as lanthanum chromite and rhenium, the use of low-Z thermal insulation, such as forsterite, in place of zirconia, and the partial replacement of zirconia by MgO equatorial windows combined with a mullite octahedron. Details of the designs, thermal characterizations, and examples of the application of these cells are described.

  2. Tracers for monitoring the activity of sodium/glucose cotransporters in health and disease

    DOE Patents [OSTI]

    Wright, Ernest M; Barrio, Jorge R; Hirayama, Bruce A; Kepe, Vladimir

    2014-09-30

    Radiolabeled tracers for sodium/glucose cotransporters (SGLTs), their synthesis, and their use are provided. The tracers are methyl or ethyl pyranosides having an equatorial hydroxyl group at carbon-2 and a C 1 preferred conformation, radiolabeled with .sup.18F, .sup.123I, or .sup.124I, or free hexoses radiolabeled with .sup.18F, .sup.123I, or .sup.124. Also provided are in vivo and in vitro techniques for using these and other tracers as analytical and diagnostic tools to study glucose transport, in health and disease, and to evaluate therapeutic interventions.

  3. Electro Acceleration in a Geomagnetic Field Line Resonance

    SciTech Connect (OSTI)

    Peter Damiano and J.R. Johnson

    2012-08-17

    A hybrid MHD kinetic electron model in dipolar coordinates is used to sim- ulate the upward current region of a geomagnetic Field Line Resonance (FLR) system for a realistic ambient electron temperatures of a keV. It is found that mirror force e ects result in potential drops su#14;cient to accelerate electrons to energies in excess of a keV in support of eld aligned currents on the or- der of 0.5 #22;A/m2. The wave energy dissipated in this acceleration would com- pletely damp an undriven FLR with an equatorial width of 0.5 RE within two resonance cycles.

  4. STRESS AND FAILURE ANALYSIS OF RAPIDLY ROTATING ASTEROID (29075) 1950DA

    SciTech Connect (OSTI)

    Hirabayashi, Masatoshi; Scheeres, Daniel J.

    2015-01-01

    Rozitis et al. recently reported that near-Earth asteroid (29075) 1950DA, whose bulk density ranges from 1.0 g cm{sup 3} to 2.4g cm{sup 3}, is a rubble pile and requires a cohesive strength of at least 44-76 Pa to keep from failing due to its fast spin period. Since their technique for giving failure conditions required the averaged stress over the whole volume, it discarded information about the asteroid's failure mode and internal stress condition. This paper develops a finite element model and revisits the stress and failure analysis of 1950DA. For the modeling, we do not consider material hardening and softening. Under the assumption of an associated flow rule and uniform material distribution, we identify the deformation process of 1950DA when its constant cohesion reaches the lowest value that keeps its current shape. The results show that to avoid structural failure the internal core requires a cohesive strength of at least 75-85 Pa. It suggests that for the failure mode of this body, the internal core first fails structurally, followed by the surface region. This implies that if cohesion is constant over the whole volume, the equatorial ridge of 1950DA results from a material flow going outward along the equatorial plane in the internal core, but not from a landslide as has been hypothesized. This has additional implications for the likely density of the interior of the body.

  5. Pollen morphology of Rhizophora L. in Peninsular Malaysia

    SciTech Connect (OSTI)

    Mohd-Arrabe', A. B.; Noraini, Talip Noraini

    2013-11-27

    Rhizophora L. are common mangrove genus in Peninsular Malaysia, it contains 3 species and 1 hybrid (R. apiculata Blume, R. mucronata Lam., R. stylosa Griff., R. x lamarckii Montrouz). This genus has some unique adaptation towards extreme environment. Rhizophora has looping aerial stilt-root and uniformly viviparous. The aim of this study is to investigate the variation in the pollen morphology of Rhizophora that can be related to their habitat. Methods include in this study is pollen observation under light and acetolysis method under scanning electron microscope. Pollen type of Rhizophora species studied except hybrid species is classified tricolporate, shape spheroidal based on ratio of length polar axis/ length of equatorial axis (1.03 - 1.09). The exine ornamentation is perforate-reticulate for R. apiculata and R. mucronata, while R. stylosa is perforate. For the only hybrid in Peninsular Malaysia, R. x lamarckii (R. apiculata x R. stylosa) differs from others, tricolpate with the absence of porate, shape is subprolate and exine ornamentation is reticulate and striate in equatorial region. Pollenkitt is present due to the salty and extreme environment. This may enhance the volume of pollenkitt present surrounding the pollen grains in Rhizophora for protection and adaptation purposes. Based on these findings, it is evident that pollen morphology is somehow related to its natural habitat.

  6. IS THE LARGE CRATER ON THE ASTEROID (2867) STEINS REALLY AN IMPACT CRATER?

    SciTech Connect (OSTI)

    Morris, A. J. W.; Price, M. C.; Burchell, M. J.

    2013-09-01

    The large crater on the asteroid (2867) Steins attracted much attention when it was first observed by the Rosetta spacecraft in 2008. Initially, it was widely thought to be unusually large compared to the size of the asteroid. It was quickly realized that this was not the case and there are other examples of similar (or larger) craters on small bodies in the same size range; however, it is still widely accepted that it is a crater arising from an impact onto the body which occurred after its formation. The asteroid (2867) Steins also has an equatorial bulge, usually considered to have arisen from redistribution of mass due to spin-up of the body caused by the YORP effect. Conversely, it is shown here that, based on catastrophic disruption experiments in laboratory impact studies, a similarly shaped body to the asteroid Steins can arise from the break-up of a parent in a catastrophic disruption event; this includes the presence of a large crater-like feature and equatorial bulge. This suggests that the large crater-like feature on Steins may not be a crater from a subsequent impact, but may have arisen directly from the fragmentation process of a larger, catastrophically disrupted parent.

  7. Impacts of rotation on three-dimensional hydrodynamics of core-collapse supernovae

    SciTech Connect (OSTI)

    Nakamura, Ko; Kuroda, Takami; Kotake, Kei [Division of Theoretical Astronomy, National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Takiwaki, Tomoya [Center for Computational Astrophysics, National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)

    2014-09-20

    We perform a series of simplified numerical experiments to explore how rotation impacts the three-dimensional (3D) hydrodynamics of core-collapse supernovae. For our systematic study, we employ a light-bulb scheme to trigger explosions and a three-flavor neutrino leakage scheme to treat deleptonization effects and neutrino losses from the proto-neutron-star interior. Using a 15 M {sub ?} progenitor, we compute 30 models in 3D with a wide variety of initial angular momentum and light-bulb neutrino luminosity. We find that the rotation can help the onset of neutrino-driven explosions for the models in which the initial angular momentum is matched to that obtained in recent stellar evolutionary calculations (?0.3-3 rad s{sup 1} at the center). For the models with larger initial angular momentum, the shock surface deforms to be more oblate due to larger centrifugal force. This not only makes the gain region more concentrated around the equatorial plane, but also makes the mass larger in the gain region. As a result, buoyant bubbles tend to be coherently formed and rise in the equatorial region, which pushes the revived shock toward ever larger radii until a global explosion is triggered. We find that these are the main reasons that the preferred direction of the explosion in 3D rotating models is often perpendicular to the spin axis, which is in sharp contrast to the polar explosions around the axis that were obtained in previous two-dimensional simulations.

  8. CASSINI VIMS OBSERVATIONS SHOW ETHANE IS PRESENT IN TITAN'S RAINFALL

    SciTech Connect (OSTI)

    Dalba, Paul A.; Buratti, Bonnie J.; Baines, Kevin H.; Sotin, Christophe; Lawrence, Kenneth J.; Brown, Robert H.; Barnes, Jason W.; Clark, Roger N.; Nicholson, Philip D.

    2012-12-20

    Observations obtained over two years by the Cassini Imaging Science Subsystem suggest that rain showers fall on the surface. Using measurements obtained by the Visual Infrared Mapping Spectrometer, we identify the main component of the rain to be ethane, with methane as an additional component. We observe five or six probable rainfall events, at least one of which follows a brief equatorial cloud appearance, suggesting that frequent rainstorms occur on Titan. The rainfall evaporates, sublimates, or infiltrates on timescales of months, and in some cases it is associated with fluvial features but not with their creation or alteration. Thus, Titan exhibits frequent 'gentle rainfall' instead of, or in addition to, more catastrophic events that cut rivers and lay down large fluvial deposits. Freezing rain may also be present, and the standing liquid may exist as puddles interspersed with patches of frost. The extensive dune deposits found in the equatorial regions of Titan imply multi-season arid conditions there, which are consistent with small, but possibly frequent, amounts of rain, in analogy to terrestrial deserts.

  9. α, α', α", α'"-meso-tetrahexyltetramethyl-calix[4]pyrrole: An easy-to-prepare, isomerically pure anion extractant with enhanced solubility in organic solvents

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

    Williams, Neil J.; Bryantsev, Vyacheslav S.; Custelcean, Radu; Seipp, Charles A.; Moyer, Bruce A.

    2016-01-29

    α, α', α", α'"-meso-Tetrahexyltetramethyl-calix[4]pyrrole is easily obtained as a single diastereomer in a one-pot reaction. It exhibits enhanced solubility in organic solvents, including aliphatic solvents, relative to its parent meso-octamethylcalix[4]pyrrole (1). Somewhat surprisingly, the tetrahexyl derivative 2 complexes with tributylmethylammonium chloride in chloroform more strongly than does 1 as shown by NMR titrations. However, 1 and 2 exhibit comparable complexation strength in extraction experiments, the difference between the NMR and extraction results being attributed to the effect of organic-phase water in the extraction systems. Mass-action analysis indicates the formation of the predominant complex TBMA+(1 or 2)Cl– in both NMR andmore » extraction systems, and equilibrium constants are reported. x-Ray crystal structures were obtained for the free ligand 2 and its complex with tetramethylammonium chloride. In addition, the free ligand crystallises in the 1,3-alt conformation with equatorial hexyl arms. In the chloride complex with 2 in its cone conformation, the hexyl arms adopt an axial orientation, enveloping the anion. DFT calculations show this binding conformation to be the most stable, mostly owing to destabilising steric interactions involving the pyrrole C–H and alkyl C–H groups positioned equatorially.« less

  10. C-Band Scanning ARM Precipitation Radar (C-SAPR) Handbook

    SciTech Connect (OSTI)

    Widener, K; Bharadwaj, N

    2012-11-13

    The C-band scanning ARM precipitation radar (C-SAPR) is a scanning polarimetric Doppler radar transmitting simultaneously in both H and V polarizations. With a 350-kW magnetron transmitter, this puts 125 kW of transmitted power for each polarization. The receiver for the C-SAPR is a National Center for Atmospheric Research (NCAR) -developed Hi-Q system operating in a coherent-on-receive mode. The ARM Climate Research Facility operates two C-SAPRs; one of them is deployed near the Southern Great Plains (SGP) Central Facility near the triangular array of X-SAPRs, and the second C-SAPR is deployed at ARMs Tropical Western Pacific (TWP) site on Manus Island in Papua New Guinea.

  11. Darwin : The Third DOE ARM TWP ARCS Site /

    SciTech Connect (OSTI)

    Clements, William E.; Jones, L. A.; Baldwin, T.; Nitschke, K.

    2002-01-01

    The United States Department of Energy's (DOE) Atmospheric Radiation Measurement (ARM) Program began operations in its Tropical Western Pacific (TWP) locale in October 1996 when the first Atmospheric Radiation and Cloud Station (ARCS) began collecting data on Manus Island in Papua New Guinea (PNG). Two years later, in November 1998, a second ARCS began operations on the island of Nauru in the Central Pacific. Now a third ARCS has begun collecting data in Darwin, Australia. The Manus, Nauru, and Darwin sites are operated through collaborative agreements with the PNG National Weather Service, The Nauru Department of Industry and Economic Development (IED), and the Australian Bureau of Meteorology's (BOM) Special Services Unit (SSU) respectively. All ARM TWP activities in the region are coordinated with the South Pacific Regional Environment Programme (SPREP) based in Apia, Samoa. The Darwin ARM site and its role in the ARM TWP Program are discussed.

  12. 1-D seismic velocity model and hypocenter relocation using double difference method around West Papua region

    SciTech Connect (OSTI)

    Sabtaji, Agung E-mail: agung.sabtaji@bmkg.go.id; Nugraha, Andri Dian

    2015-04-24

    West Papua region has fairly high of seismicity activities due to tectonic setting and many inland faults. In addition, the region has a unique and complex tectonic conditions and this situation lead to high potency of seismic hazard in the region. The precise earthquake hypocenter location is very important, which could provide high quality of earthquake parameter information and the subsurface structure in this region to the society. We conducted 1-D P-wave velocity using earthquake data catalog from BMKG for April, 2009 up to March, 2014 around West Papua region. The obtained 1-D seismic velocity then was used as input for improving hypocenter location using double-difference method. The relocated hypocenter location shows fairly clearly the pattern of intraslab earthquake beneath New Guinea Trench (NGT). The relocated hypocenters related to the inland fault are also observed more focus in location around the fault.

  13. PowerPoint Presentation

    Gasoline and Diesel Fuel Update (EIA)

    LNG World LNG Imports 1964 - 2007 World LNG Imports 1964 - 2007 0 20 40 60 80 100 120 140 160 180 200 1964 1968 1972 1976 1980 1984 1988 1992 1996 2000 2004 Americas Total Europe Total Asia in mtpa 7.7%pa 2 LNG 0 4 8 12 16 1 9 6 8 1 9 7 3 1 9 7 8 1 9 8 3 1 9 8 8 1 9 9 3 1 9 9 8 2 0 0 3 Algeria Trinidad Egypt Nigeria Eq. Guinea M. East Pacific Basin in mtpa US LNG Imports by Source 1968-2007 US LNG Imports by Source 1968-2007 3 LNG Regional LNG Production 1990 - 2007 Regional LNG Production 1990

  14. The effects of repeated low-dose sarin exposure

    SciTech Connect (OSTI)

    Shih, T.-M. . E-mail: tsungming.a.shih@us.army.mil; Hulet, S.W.; McDonough, J.H.

    2006-09-01

    This project assessed the effects of repeated low-dose exposure of guinea pigs to the organophosphorus nerve agent sarin. Animals were injected once a day, 5 days per week (Monday-Friday), for 2 weeks with fractions (0.3x, 0.4x, 0.5x, or 0.6x) of the established LD{sub 5} dose of sarin (42 {mu}g/kg, s.c.). The animals were assessed for changes in body weight, red blood cell (RBC) acetylcholinesterase (AChE) levels, neurobehavioral reactions to a functional observational battery (FOB), cortical electroencephalographic (EEG) power spectrum, and intrinsic acetylcholine (ACh) neurotransmitter (NT) regulation over the 2 weeks of sarin exposure and for up to 12 days postinjection. No guinea pig receiving 0.3, 0.4 or 0.5 x LD{sub 5} of sarin showed signs of cortical EEG seizures despite decreases in RBC AChE levels to as low as 10% of baseline, while seizures were evident in animals receiving 0.6 x LD{sub 5} of sarin as early as the second day; subsequent injections led to incapacitation and death. Animals receiving 0.5 x LD{sub 5} sarin showed obvious signs of cholinergic toxicity; overall, 2 of 13 animals receiving 0.5 x LD{sub 5} sarin died before all 10 injections were given, and there was a significant increase in the angle of gait in the animals that lived. By the 10th day of injection, the animals receiving saline were significantly easier to remove from their cages and handle and significantly less responsive to an approaching pencil and touch on the rump in comparison with the first day of testing. In contrast, the animals receiving 0.4 x LD{sub 5} sarin failed to show any significant reductions in their responses to an approaching pencil and a touch on the rump as compared with the first day. The 0.5 x LD{sub 5} sarin animals also failed to show any significant changes to the approach and touch responses and did not adjust to handling or removal from the cage from the first day of injections to the last day of handling. Thus, the guinea pigs receiving the 0.4 and 0.5 x LD{sub 5} doses of sarin failed to habituate to some aspects of neurobehavioral testing. Spectral analysis of EEG data suggested that repeated sarin exposure may disrupt normal sleeping patterns (i.e., lower frequency bandwidths). While these EEG changes returned to relative normalcy 6 days after the last injection in animals receiving 0.4 x LD{sub 5} sarin, these changes were still observed in the animals that received 0.5 x LD{sub 5} sarin. Ten to twelve days after the last sarin injection (in 0.4 x LD{sub 5} group only), neurochemical data showed that striatal choline levels were reduced in comparison to the saline group. At this time, atropine sulfate (5 mg/kg, i.p.) challenge resulted in a transient elevation in striatal ACh levels in animals exposed to repeated 0.4 x LD{sub 5} sarin as well as in control animals. No evidence of brain or heart pathology was found in any guinea pig that survived all 10 sarin injections.

  15. Bioinspired design of redox-active ligands for multielectron catalysis: Effects of positioning pyrazine reservoirs on cobalt for electro- and photocatalytic generation of hydrogen from water

    SciTech Connect (OSTI)

    Jurss, Jonah W.; Khnayzer, Rony S.; Panetier, Julien A.; El Roz, Karim A.; Nichols, Eva M.; Head-Gordon, Martin; Long, Jeffrey R.; Castellano, Felix N.; Chang, Christopher J.

    2015-06-09

    Mononuclear metalloenzymes in nature can function in cooperation with precisely positioned redox-active organic cofactors in order to carry out multielectron catalysis. Inspired by the finely tuned redox management of these bioinorganic systems, we present the design, synthesis, and experimental and theoretical characterization of a homologous series of cobalt complexes bearing redox-active pyrazines. These donor moieties are locked into key positions within a pentadentate ligand scaffold in order to evaluate the effects of positioning redox non-innocent ligands on hydrogen evolution catalysis. Both metal- and ligand-centered redox features are observed in organic as well as aqueous solutions over a range of pH values, and comparison with analogs bearing redox-inactive zinc(II) allows for assignments of ligand-based redox events. Varying the geometric placement of redox non-innocent pyrazine donors on isostructural pentadentate ligand platforms results in marked effects on observed cobalt-catalyzed proton reduction activity. Electrocatalytic hydrogen evolution from weak acids in acetonitrile solution, under diffusion-limited conditions, reveals that the pyrazine donor of axial isomer 1-Co behaves as an unproductive electron sink, resulting in high overpotentials for proton reduction, whereas the equatorial pyrazine isomer complex 2-Co is significantly more active for hydrogen generation at lower voltages. Addition of a second equatorial pyrazine in complex 3-Co further minimizes overpotentials required for catalysis. The equatorial derivative 2-Co is also superior to its axial 1-Co congener for electrocatalytic and visible-light photocatalytic hydrogen generation in biologically relevant, neutral pH aqueous media. Density functional theory calculations (B3LYP-D2) indicate that the first reduction of catalyst isomers 1-Co, 2-Co, and 3-Co is largely metal-centered while the second reduction occurs at pyrazine. Taken together, the data establish that proper positioning of non-innocent pyrazine ligands on a single cobalt center is indeed critical for promoting efficient hydrogen catalysis in aqueous media, akin to optimally positioned redox-active cofactors in metalloenzymes. In a broader sense, these findings highlight the significance of electronic structure considerations in the design of effective electronhole reservoirs for multielectron transformations.

  16. Bioinspired design of redox-active ligands for multielectron catalysis: Effects of positioning pyrazine reservoirs on cobalt for electro- and photocatalytic generation of hydrogen from water

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

    Jurss, Jonah W.; Khnayzer, Rony S.; Panetier, Julien A.; El Roz, Karim A.; Nichols, Eva M.; Head-Gordon, Martin; Long, Jeffrey R.; Castellano, Felix N.; Chang, Christopher J.

    2015-06-09

    Mononuclear metalloenzymes in nature can function in cooperation with precisely positioned redox-active organic cofactors in order to carry out multielectron catalysis. Inspired by the finely tuned redox management of these bioinorganic systems, we present the design, synthesis, and experimental and theoretical characterization of a homologous series of cobalt complexes bearing redox-active pyrazines. These donor moieties are locked into key positions within a pentadentate ligand scaffold in order to evaluate the effects of positioning redox non-innocent ligands on hydrogen evolution catalysis. Both metal- and ligand-centered redox features are observed in organic as well as aqueous solutions over a range of pHmore » values, and comparison with analogs bearing redox-inactive zinc(II) allows for assignments of ligand-based redox events. Varying the geometric placement of redox non-innocent pyrazine donors on isostructural pentadentate ligand platforms results in marked effects on observed cobalt-catalyzed proton reduction activity. Electrocatalytic hydrogen evolution from weak acids in acetonitrile solution, under diffusion-limited conditions, reveals that the pyrazine donor of axial isomer 1-Co behaves as an unproductive electron sink, resulting in high overpotentials for proton reduction, whereas the equatorial pyrazine isomer complex 2-Co is significantly more active for hydrogen generation at lower voltages. Addition of a second equatorial pyrazine in complex 3-Co further minimizes overpotentials required for catalysis. The equatorial derivative 2-Co is also superior to its axial 1-Co congener for electrocatalytic and visible-light photocatalytic hydrogen generation in biologically relevant, neutral pH aqueous media. Density functional theory calculations (B3LYP-D2) indicate that the first reduction of catalyst isomers 1-Co, 2-Co, and 3-Co is largely metal-centered while the second reduction occurs at pyrazine. Taken together, the data establish that proper positioning of non-innocent pyrazine ligands on a single cobalt center is indeed critical for promoting efficient hydrogen catalysis in aqueous media, akin to optimally positioned redox-active cofactors in metalloenzymes. In a broader sense, these findings highlight the significance of electronic structure considerations in the design of effective electron–hole reservoirs for multielectron transformations.« less

  17. Tokamak reactor for treating fertile material or waste nuclear by-products

    DOE Patents [OSTI]

    Kotschenreuther, Michael T.; Mahajan, Swadesh M.; Valanju, Prashant M.

    2012-10-02

    Disclosed is a tokamak reactor. The reactor includes a first toroidal chamber, current carrying conductors, at least one divertor plate within the first toroidal chamber and a second chamber adjacent to the first toroidal chamber surrounded by a section that insulates the reactor from neutrons. The current carrying conductors are configured to confine a core plasma within enclosed walls of the first toroidal chamber such that the core plasma has an elongation of 1.5 to 4 and produce within the first toroidal chamber at least one stagnation point at a perpendicular distance from an equatorial plane through the core plasma that is greater than the plasma minor radius. The at least one divertor plate and current carrying conductors are configured relative to one another such that the current carrying conductors expand the open magnetic field lines at the divertor plate.

  18. Effects of self-heating and phase change on the thermal profile of hydrogen isotopes in confined geometries

    SciTech Connect (OSTI)

    Baxamusa, S. Field, J.; Dylla-Spears, R.; Kozioziemski, B.; Suratwala, T.; Sater, J.

    2014-03-28

    Growth of high-quality single-crystal hydrogen in confined geometries relies on the in situ formation of seed crystals. Generation of deuterium-tritium seed crystals in a confined geometry is governed by three effects: self-heating due to tritium decay, external thermal environment, and latent heat of phase change at the boundary between hydrogen liquid and vapor. A detailed computation of the temperature profile for liquid hydrogen inside a hollow shell, as is found in inertial confinement fusion research, shows that seeds are likely to form at the equatorial plane of the shell. Radioactive decay of tritium to helium slowly alters the composition of the hydrogen vapor, resulting in a modified temperature profile that encourages seed formation at the top of the shell. We show that the computed temperature profile is consistent with a variety of experimental observations.

  19. Laser irradiance scaling in polar direct drive implosions on the National Ignition Facility

    SciTech Connect (OSTI)

    Murphy, T. J.; Krasheninnikova, N. S.; Kyrala, G. A.; Bradley, P. A.; Baumgaertel, J. A.; Cobble, J. A.; Hakel, P.; Hsu, S. C.; Kline, J. L.; Montgomery, D. S.; Obrey, K. A. D.; Shah, R. C.; Tregillis, I. L.; Schmitt, M. J.; Kanzleiter, R. J.; Batha, S. H.; Wallace, R. J.; Bhandarkar, S. D.; Fitzsimmons, P.; Hoppe, M. L.; Nikroo, A.; Hohenberger, M.; McKenty, P. W.; Rinderknecht, H. G.; Rosenberg, M. J.; Petrasso, R. D.

    2015-09-17

    Polar-direct-drive experiments conducted at the National Ignition Facility [E. I. Moses, Fusion Sci. Technol. 54, 361 (2008)] performed at laser irradiance between 1 and 2×1015 W/cm2 exhibit increased hard x-ray emission, decreased neutron yield, and reduced areal density as the irradiance is increased. Experimental x-ray images at the higher irradiances show x-ray emission at the equator, as well as degraded symmetry, that is not predicted in hydrodynamic simulations using flux-limited energy transport, but that appear when non-local electron transport together with a model to account for cross beam energy transfer (CBET) is utilized. The reduction in laser power for equatorial beams required in the simulations to reproduce the effects of CBET on the observed symmetry also reproduces the yield degradation consistent with experimental data.

  20. New opportunities for quasielastic and inelastic neutron scattering at steady-state sources using mechanical selection of the incident and final neutron energy

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

    Mamantov, Eugene

    2015-06-12

    We propose a modification of the neutron wide-angle velocity selector (WAVES) device that enables inelastic (in particular, quasielastic) scattering measurements not relying on the neutron time-of-flight. The proposed device is highly suitable for a steady-state neutron source, somewhat similar to a triple-axis spectrometer, but with simultaneous selection of the incident and final neutron energy over a broad range of scattering momentum transfer. Both the incident and final neutron velocities are defined by the WAVES geometry and rotation frequency. The variable energy transfer is achieved through the natural variation of the velocity of the transmitted neutrons as a function of themore » scattering angle component out of the equatorial plane.« less

  1. Quantitative analysis of the x-ray diffraction intensities of undulated smectic phases in bent-core liquid crystals

    SciTech Connect (OSTI)

    Folcia, C. L.; Etxebarria, J.; Ortega, J.

    2007-07-15

    X-ray diffraction diagrams of undulated smectic phases in bent-core liquid crystals have been theoretically studied. The intensities of the reflections have been obtained for different layer modulations, and a general expression has been deduced for orthogonal cells in terms of the different harmonics of the distortion. The case of sinusoidal modulation is especially simple and has been studied also in oblique cells. High-quality x-ray measurements of three compounds reported in the literature have been analyzed as examples. In all cases it has been deduced that the modulation is sinusoidal and its amplitude has been easily obtained by fitting the experimental intensities. Equatorial (h0) reflections have been also considered to obtain information about the structure of defects at the maxima and minima of the undulation.

  2. Double-reconnected magnetic structures driven by Kelvin-Helmholtz vortices at the Earth's magnetosphere

    SciTech Connect (OSTI)

    Borgogno, D.; Califano, F.; Pegoraro, F.; Faganello, M.

    2015-03-15

    In an almost collisionless magnetohydrodynamic plasma in a relatively strong magnetic field, stresses can be conveyed far from the region where they are exerted, e.g., through the propagation of Alfvn waves. The forced dynamics of line-tied magnetic structures in solar and stellar coronae (see, e.g., A. F. Rappazzo and E. N. Parker, Astrophys. J. 773, L2 (2013) and references therein) is a paradigmatic case. Here, we investigate how this action at a distance develops from the equatorial region of the Kelvin-Helmholtz unstable flanks of the Earth's magnetosphere leading to the onset, at mid latitude in both hemispheres, of correlated double magnetic field line reconnection events that can allow the solar wind plasma to enter the Earth's magnetosphere.

  3. INTERNAL GRAVITY WAVES IN MASSIVE STARS: ANGULAR MOMENTUM TRANSPORT

    SciTech Connect (OSTI)

    Rogers, T. M.; Lin, D. N. C.; McElwaine, J. N.; Lau, H. H. B. E-mail: lin@ucolick.org E-mail: hblau@astro.uni-bonn.de

    2013-07-20

    We present numerical simulations of internal gravity waves (IGW) in a star with a convective core and extended radiative envelope. We report on amplitudes, spectra, dissipation, and consequent angular momentum transport by such waves. We find that these waves are generated efficiently and transport angular momentum on short timescales over large distances. We show that, as in Earth's atmosphere, IGW drive equatorial flows which change magnitude and direction on short timescales. These results have profound consequences for the observational inferences of massive stars, as well as their long term angular momentum evolution. We suggest IGW angular momentum transport may explain many observational mysteries, such as: the misalignment of hot Jupiters around hot stars, the Be class of stars, Ni enrichment anomalies in massive stars, and the non-synchronous orbits of interacting binaries.

  4. Visualization and analysis of eddies in a global ocean simulation

    SciTech Connect (OSTI)

    Williams, Sean J; Hecht, Matthew W; Petersen, Mark; Strelitz, Richard; Maltrud, Mathew E; Ahrens, James P; Hlawitschka, Mario; Hamann, Bernd

    2010-10-15

    Eddies at a scale of approximately one hundred kilometers have been shown to be surprisingly important to understanding large-scale transport of heat and nutrients in the ocean. Due to difficulties in observing the ocean directly, the behavior of eddies below the surface is not very well understood. To fill this gap, we employ a high-resolution simulation of the ocean developed at Los Alamos National Laboratory. Using large-scale parallel visualization and analysis tools, we produce three-dimensional images of ocean eddies, and also generate a census of eddy distribution and shape averaged over multiple simulation time steps, resulting in a world map of eddy characteristics. As expected from observational studies, our census reveals a higher concentration of eddies at the mid-latitudes than the equator. Our analysis further shows that mid-latitude eddies are thicker, within a range of 1000-2000m, while equatorial eddies are less than 100m thick.

  5. Synthesis, NMR spectra, and structure of rhodium hydride complexes with Rh-Sn bonds

    SciTech Connect (OSTI)

    Krut'ko, B.P.; Permin, A.B.; Petrosyan, V.S.; Reutov, O.A.

    1985-06-20

    The authors study the hydride complexes using Sn 119 and H 1 NMR spectroscopy. The spectra were taken in a pulse mode on a Varian FT-80A spectrometer equipped with a wideband system at 29.66 and 79.54 MHz. The Sn 119 and H 1 NMR spectral parameters for a solution of the complex (Bu/sub 4/N)/sub 3/ (HRh(SnCl/sub 3/)/sub 5/) in CD/sub 3/CN are shown, the spectra show that the (HRh(SnCl/sub 3/)/sub 5/)/sup 3 -/ anion has octahedral structure with four equatorial and one axial Rh-Sn bonds. New rhodium hydride complexes with general formula (R/sub 4/N)/sub 3/(HRh(SnCl/sub 3/)/sub 5/) were synthesized.

  6. Laser generated proton beam focusing and high temperature isochoric heating of solid matter

    SciTech Connect (OSTI)

    Snavely, R. A.; Hatchett, S. P.; Key, M. H.; Langdon, A. B.; Lasinski, B. F.; MacKinnon, A. J.; Patel, P.; Town, R.; Wilks, S. C.; Zhang, B.; Akli, K.; Hey, D.; King, J.; Chen, Z.; Izawa, Y.; Kitagawa, Y.; Kodama, R.; Lei, A.; Tampo, M.; Tanaka, K. A.

    2007-09-15

    The results of laser-driven proton beam focusing and heating with a high energy (170 J) short pulse are reported. Thin hemispherical aluminum shells are illuminated with the Gekko petawatt laser using 1 {mu}m light at intensities of {approx}3x10{sup 18} W/cm{sup 2} and measured heating of thin Al slabs. The heating pattern is inferred by imaging visible and extreme-ultraviolet light Planckian emission from the rear surface. When Al slabs 100 {mu}m thick were placed at distances spanning the proton focus beam waist, the highest temperatures were produced at 0.94x the hemisphere radius beyond the equatorial plane. Isochoric heating temperatures reached 81 eV in 15 {mu}m thick foils. The heating with a three-dimensional Monte Carlo model of proton transport with self-consistent heating and proton stopping in hot plasma was modeled.

  7. A tropical influence on global climate

    SciTech Connect (OSTI)

    Schneider, E.K.; Kirtman, B.P.; Lindzen, R.S.

    1997-05-15

    A potential influence of tropical sea surface temperature on the global climate response to a doubling of the CO{sub 2} concentration is tested using an atmospheric general circulation model coupled to a slab mixed layer ocean. The warming is significantly reduced when sea surface temperatures in the eastern equatorial Pacific cold tongue region between latitudes 2.25{degrees}N and 2.25{degrees}S are held at the control simulation values. Warming of the global mean temperature outside of the cold tongue region is reduced from 2.4{degrees}C in the unconstrained case to 1.9{degrees}C when the sea surface temperature constraint is applied. The decrease in the warming results from a positive net heat flux into the ocean cold tongue region and implicit heat storage in the subsurface ocean, induced by horizontal atmospheric heat fluxes. The reduced surface temperature warming outside of the cold tongue region is due to reduction in the downward longwave radiative flux at the surface, caused in turn by reduced atmospheric temperature and moisture. The global mean surface temperature responds to the heat storage in the ocean as if the global mean radiative forcing due to the doubled CO{sub 2} (approximately 4 W m{sup {minus}2}) was reduced by the value of the global mean heat flux into the ocean. This mechanism also provides a possible explanation for the observed high correlation on interannual timescales between the global mean tropospheric temperature and sea surface temperature in the eastern tropical Pacific. The results emphasize the importance of correctly modeling the dynamical processes in the ocean and atmosphere that help determine the sea surface temperature in the equatorial eastern Pacific, in addition to the thermodynamical processes, in projecting global warming. 23 refs., 8 figs.

  8. ON THE SIZE, SHAPE, AND DENSITY OF DWARF PLANET MAKEMAKE

    SciTech Connect (OSTI)

    Brown, M. E.

    2013-04-10

    A recent stellar occultation by the dwarf planet Makemake provided an excellent opportunity to measure the size and shape of one of the largest objects in the Kuiper belt. The analysis of these results provided what were reported to be precise measurements of the lengths of the projected axes, the albedo, and even the density of Makemake, but these results were, in part, derived from qualitative arguments. We reanalyzed the occultation timing data using a quantitative statistical description, and, in general, found the previously reported results on the shape of Makemake to be unjustified. In our solution, in which we use our inference from photometric data that Makemake is being viewed nearly pole-on, we find a 1{sigma} upper limit to the projected elongation of Makemake of 1.02, with measured equatorial diameter of 1434 {+-} 14 km and a projected polar diameter of 1422 {+-} 14 km, yielding an albedo of 0.81{sup +0.01}{sub -0.02}. If we remove the external constraint on the pole position of Makemake, we find instead a 1{sigma} upper limit to the elongation of 1.06, with a measured equatorial diameter of 1434{sup +48}{sub -18} km and a projected polar diameter of 1420{sup +18}{sub -24} km, yielding an albedo of 0.81{sup +0.03}{sub -0.05}. Critically, we find that the reported measurement of the density of Makemake was based on the misapplication of the volatile retention models. A corrected analysis shows that the occultation measurements provide no meaningful constraint on the density of Makemake.

  9. On the connection between continental-scale land surface processes and the tropical climate in a coupled ocean-atmosphere-land system

    SciTech Connect (OSTI)

    Ma, Hsi-Yen; Mechoso, C. R.; Xue, Yongkang; Xiao, Heng; Neelin, David; Ji, Xuan

    2013-11-15

    The impact of global tropical climate to perturbations in land surface processes (LSP) are evaluated using perturbations given by different LSP representations of continental-scale in a global climate model that includes atmosphere-ocean interactions. One representation is a simple land scheme, which specifies climatological albedos and soil moisture availability. The other representation is the more comprehensive Simplified Simple Biosphere Model, which allows for interactive soil moisture and vegetation biophysical processes. The results demonstrate that LSP processes such as interactive soil moisture and vegetation biophysical processes have strong impacts on the seasonal mean states and seasonal cycles of global precipitation, clouds, and surface air temperature. The impact is especially significant over the tropical Pacific. To explore the mechanisms for such impact, different LSP representations are confined to selected continental-scale regions where strong interactions of climate-vegetation biophysical processes are present. We find that the largest impact is mainly from LSP perturbations over the tropical African continent. The impact is through anomalous convective heating in tropical Africa due to changes in the surface heat fluxes, which in turn affect basinwide teleconnections in the Pacific through equatorial wave dynamics. The modifications in the equatorial Pacific climate are further enhanced by strong air-sea coupling between surface wind stress and upwelling, as well as effect of ocean memory. Our results further suggest that correct representations of land surface processes, land use change and the associated changes in the deep convection over tropical Africa are crucial to reducing the uncertainty when performing future climate projections under different climate change scenarios.

  10. The 4.5 ?m full-orbit phase curve of the hot Jupiter HD 209458b

    SciTech Connect (OSTI)

    Zellem, Robert T.; Griffith, Caitlin A.; Showman, Adam P.; Lewis, Nikole K.; Knutson, Heather A.; Fortney, Jonathan J.; Laughlin, Gregory; Cowan, Nicolas B.; Agol, Eric; Burrows, Adam; Charbonneau, David; Deming, Drake; Langton, Jonathan

    2014-07-20

    The hot Jupiter HD 209458b is particularly amenable to detailed study as it is among the brightest transiting exoplanet systems currently known (V-mag = 7.65; K-mag = 6.308) and has a large planet-to-star contrast ratio. HD 209458b is predicted to be in synchronous rotation about its host star with a hot spot that is shifted eastward of the substellar point by superrotating equatorial winds. Here we present the first full-orbit observations of HD 209458b, in which its 4.5 ?m emission was recorded with Spitzer/IRAC. Our study revises the previous 4.5 ?m measurement of HD 209458b's secondary eclipse emission downward by ?35% to 0.1391%{sub ?0.0069%}{sup +0.0072%}, changing our interpretation of the properties of its dayside atmosphere. We find that the hot spot on the planet's dayside is shifted eastward of the substellar point by 40.9 6.0, in agreement with circulation models predicting equatorial superrotation. HD 209458b's dayside (T{sub bright} = 1499 15 K) and nightside (T{sub bright} = 972 44 K) emission indicate a day-to-night brightness temperature contrast smaller than that observed for more highly irradiated exoplanets, suggesting that the day-to-night temperature contrast may be partially a function of the incident stellar radiation. The observed phase curve shape deviates modestly from global circulation model predictions potentially due to disequilibrium chemistry or deficiencies in the current hot CH{sub 4} line lists used in these models. Observations of the phase curve at additional wavelengths are needed in order to determine the possible presence and spatial extent of a dayside temperature inversion, as well as to improve our overall understanding of this planet's atmospheric circulation.

  11. Quantification of the epitope diversity of HIV-1-specific binding antibodies by peptide microarrays for global HIV-1 vaccine development

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

    Stephenson, Kathryn E.; Neubauer, George H.; Reimer, Ulf; Pawlowski, Nikolaus; Knaute, Tobias; Zerweck, Johannes; Korber, Bette T.; Barouch, Dan H.

    2014-11-14

    An effective vaccine against human immunodeficiency virus type 1 (HIV-1) will have to provide protection against a vast array of different HIV-1 strains. Current methods to measure HIV-1-specific binding antibodies following immunization typically focus on determining the magnitude of antibody responses, but the epitope diversity of antibody responses has remained largely unexplored. Here we describe the development of a global HIV-1 peptide microarray that contains 6564 peptides from across the HIV-1 proteome and covers the majority of HIV-1 sequences in the Los Alamos National Laboratory global HIV-1 sequence database. Using this microarray, we quantified the magnitude, breadth, and depth ofmore » IgG binding to linear HIV-1 sequences in HIV-1-infected humans and HIV-1-vaccinated humans, rhesus monkeys and guinea pigs. The microarray measured potentially important differences in antibody epitope diversity, particularly regarding the depth of epitope variants recognized at each binding site. Our data suggest that the global HIV-1 peptide microarray may be a useful tool for both preclinical and clinical HIV-1 research.« less

  12. Human radiation experiments associated with the US Department of Energy and its predecessors

    SciTech Connect (OSTI)

    1995-07-01

    This document contains a listing, description, and selected references for documented human radiation experiments sponsored, supported, or performed by the US Department of Energy (DOE) or its predecessors, including the US Energy Research and Development Administration (ERDA), the US Atomic Energy Commission (AEC), the Manhattan Engineer District (MED), and the Off ice of Scientific Research and Development (OSRD). The list represents work completed by DOE`s Off ice of Human Radiation Experiments (OHRE) through June 1995. The experiment list is available on the Internet via a Home Page on the World Wide Web (http://www.ohre.doe.gov). The Home Page also includes the full text of Human Radiation Experiments. The Department of Energy Roadmap to the Story and the Records (DOE/EH-0445), published in February 1995, to which this publication is a supplement. This list includes experiments released at Secretary O`Leary`s June 1994 press conference, as well as additional studies identified during the 12 months that followed. Cross-references are provided for experiments originally released at the press conference; for experiments released as part of The DOE Roadmap; and for experiments published in the 1986 congressional report entitled American Nuclear Guinea Pigs: Three Decades of Radiation Experiments on US Citizens. An appendix of radiation terms is also provided.

  13. Atmospheric Radiation Measurement (ARM) Data from the Tropical Western Pacific (TWP) Site.

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

    ARM maintains four major, permanent sites for data collection and deploys the ARM Mobile Facility to other sites as determined. The Tropical Western Pacific (TWP) site is one of the four fixed sites. It consists of three climate research facilities; the Manus facility on Los Negros Island in Manus, Papua New Guinea (established in 1996); the Nauru facility on Nauru Island, Republic of Nauru (1998); and the Darwin facility in Darwin, Northern Territory, Australia (2002). The operations are supported by government agencies in each host country. Covering the area roughly between 10 degrees N and 10 degrees S of the equator and from 130 degrees E to 167 degrees E, the TWP locale includes a region that plays a large role in the interannual variability observed in the global climate system. More than 250,000 TWP data sets from 1996 to the present reside in the ARM Archive. Begin at the TWP information page for links or access data directly from the ARM Archive at http://www.archive.arm.gov/. Users will need to register for a password, but all files are then free for viewing or downloading. The ARM Archive physically resides at the Oak Ridge National Laboratory.

  14. Assessing health impacts in complex eco-epidemiological settings in the humid tropics: Modular baseline health surveys

    SciTech Connect (OSTI)

    Winkler, Mirko S.; Divall, Mark J.; Krieger, Gary R.; Schmidlin, Sandro; Magassouba, Mohamed L.; Knoblauch, Astrid M.; Singer, Burton H.; Utzinger, Juerg

    2012-02-15

    The quantitative assessment of health impacts has been identified as a crucial feature for realising the full potential of health impact assessment (HIA). In settings where demographic and health data are notoriously scarce, but there is a broad range of ascertainable ecological, environmental, epidemiological and socioeconomic information, a diverse toolkit of data collection strategies becomes relevant for the mainly small-area impacts of interest. We present a modular, cross-sectional baseline health survey study design, which has been developed for HIA of industrial development projects in the humid tropics. The modular nature of our toolkit allows our methodology to be readily adapted to the prevailing eco-epidemiological characteristics of a given project setting. Central to our design is a broad set of key performance indicators, covering a multiplicity of health outcomes and determinants at different levels and scales. We present experience and key findings from our modular baseline health survey methodology employed in 14 selected sentinel sites within an iron ore mining project in the Republic of Guinea. We argue that our methodology is a generic example of rapid evidence assembly in difficult-to-reach localities, where improvement of the predictive validity of the assessment and establishment of a benchmark for longitudinal monitoring of project impacts and mitigation efforts is needed.

  15. The Gut Microbiota of Rural Papua New Guineans: Composition, Diversity Patterns, and Ecological Processes

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

    Martínez, Inés; Stegen, James C.; Maldonado-Gómez, Maria X.; Eren, A. Murat; Siba, Peter M.; Greenhill, Andrew R.; Walter, Jens

    2015-04-01

    Comparisons between the fecal microbiota of humans from industrialized and non-industrialized communities indicate a pronounced impact of westernization on the diversity and composition of the human gut microbiota. However, the exact consequences of westernization on community characteristics are still insufficiently understood, and the ecological processes that drive differences have not been elucidated. Here we have compared the fecal microbiota of adults from two non-industrialized regions in Papua New Guinea (PNG) with that of United States (US) residents. Papua New Guineans harbor communities with greater bacterial diversity but lower inter-individual variation. Although the fecal microbiota in PNG and US was largelymore » dominated by shared bacterial lineages, the relative abundance of 25 families, 45 genera, and 230 species-level OTUs differed, and 47 core OTUs in PNG were undetectable in US residents. To gain insight into the ecological mechanisms that cause the observed differences, we quantified community assembly processes in PNG and US microbiomes using a null modeling approach. This analysis demonstrated a significant higher rate of bacterial dispersal in PNG and divergent selective environments in the US. Interestingly, equivalent findings were obtained for other datasets comparing industrialized and non-industrialized microbiomes. Overall, the findings demonstrate a dominant role for microbial dispersal in shaping the human gut microbiota in non-industrialized societies, and point to differential selection pressures across individuals as a major factor shaping microbiomes associated with modern lifestyle.« less

  16. Mineral industries of Australia, Canada, and Oceania (including a discussion of Antarctica's mineral resources). Mineral perspective

    SciTech Connect (OSTI)

    Kimbell, C.L.; Lyday, T.Q.; Newman, H.H.

    1985-12-01

    The Bureau of Mines report gives the mineral industry highlights of two of the world's major mineral producing countries, Australia and Canada, and seven Pacific island nations or territories--Fiji, New Caledonia, New Zealand, Papua New Guinea, Republic of Nauru, Solomon Islands, and Vanuatu. The mineral resources of Antarctica are also discussed. Because of the size of the Australian and Canadian mineral industries, summary reviews are presented for each of the States, Provinces, or Territories. The most current information available from all nations is given on major minerals or mineral-commodity production, share of world production, and reserves. Reported also are significant mining companies, locations and capacities of their main facilities, and their share of domestic production. Other information is provided on mineral-related trade with the United States, government mineral policy, energy production-consumption and trade, the mining industry labor force, and prospects for the mineral industry. Maps show the locations of selected mineral deposits, oilfields and gasfields, mines, and processing facilities including iron and steel plants, nonferrous smelters and refineries, and cement plants, as well as infrastructure pertinent to the mineral industry.

  17. TORUS AND ACTIVE GALACTIC NUCLEUS PROPERTIES OF NEARBY SEYFERT GALAXIES: RESULTS FROM FITTING INFRARED SPECTRAL ENERGY DISTRIBUTIONS AND SPECTROSCOPY

    SciTech Connect (OSTI)

    Alonso-Herrero, Almudena; Ramos Almeida, Cristina; Mason, Rachel; Asensio Ramos, Andres; Rodriguez Espinosa, Jose Miguel; Perez-Garcia, Ana M.; Roche, Patrick F.; Levenson, Nancy A.; Elitzur, Moshe; Packham, Christopher; Young, Stuart; Diaz-Santos, Tanio

    2011-08-01

    We used the CLUMPY torus models and a Bayesian approach to fit the infrared spectral energy distributions and ground-based high angular resolution mid-infrared spectroscopy of 13 nearby Seyfert galaxies. This allowed us to put tight constraints on torus model parameters such as the viewing angle i, the radial thickness of the torus Y, the angular size of the cloud distribution {sigma}{sub torus}, and the average number of clouds along radial equatorial rays N{sub 0}. We found that the viewing angle i is not the only parameter controlling the classification of a galaxy into type 1 or type 2. In principle, type 2s could be viewed at any viewing angle i as long as there is one cloud along the line of sight. A more relevant quantity for clumpy media is the probability for an active galactic nucleus (AGN) photon to escape unabsorbed. In our sample, type 1s have relatively high escape probabilities, P{sub esc} {approx} 12%-44%, while type 2s, as expected, tend to have very low escape probabilities. Our fits also confirmed that the tori of Seyfert galaxies are compact with torus model radii in the range 1-6 pc. The scaling of the models to the data also provided the AGN bolometric luminosities L{sub bol}(AGN), which were found to be in good agreement with estimates from the literature. When we combined our sample of Seyfert galaxies with a sample of PG quasars from the literature to span a range of L{sub bol}(AGN) {approx} 10{sup 43}-10{sup 47} erg s{sup -1}, we found plausible evidence of the receding torus. That is, there is a tendency for the torus geometrical covering factor to be lower (f{sub 2} {approx} 0.1-0.3) at high AGN luminosities than at low AGN luminosities (f{sub 2} {approx} 0.9-1 at {approx}10{sup 43}-10{sup 44} erg s{sup -1}). This is because at low AGN luminosities the tori appear to have wider angular sizes (larger {sigma}{sub torus}) and more clouds along radial equatorial rays. We cannot, however, rule out the possibility that this is due to contamination by extended dust structures not associated with the dusty torus at low AGN luminosities, since most of these in our sample are hosted in highly inclined galaxies.

  18. LLE Review Quarterly Report January - March 2012. Volume 130

    SciTech Connect (OSTI)

    Shvydky, Alex

    2012-03-01

    This volume of the LLE Review, covering JanuaryMarch 2012, features OMEGA Polar-Drive Target Designs, by P. B. Radha, J. A. Marozas, F. J. Marshall, A. Shvydky, T. J. B. Collins, V. N. Goncharov, R. L. McCrory, P. W. McKenty, D. D. Meyerhofer, T. C. Sangster, and S. Skupsky. This article (p. 57) describes low-adiabat, cryogenic-deuteriumtritium, and warm-plastic-shell polar-drive (PD)implosion designs for the OMEGA laser. The designs are at two different on-target laser intensities, each at a different in-flight aspect ratio (IFAR). The first design permits one to study implosion energetics and target performance closer to ignition-relevant intensities (7 X 1014 W/cm2 at the quarter-critical surface), where nonlocal heat conduction and laserplasma interactions can play an important role, but at lower values of IFAR (~22). The second design permits one to study implosion energetics and target performance at a lower intensity (3 X 1014 W/cm2) but at higher IFAR (~32), where the shell instability can play an important role. The higher IFAR designs are accessible on the existing OMEGA Laser System only at lower intensities. Implosions at ignition-relevant intensities can be obtained only by reducing target radius, although only at smaller values of IFAR. Polar-drive geometry requires repointing the laser beams to improve shell symmetry. The higher-intensity designs optimize target performance by repointing beams to a lesser extent and compensate for the reduced equatorial drive by increasing beam energies for the repointed beams and using custom beam profiles that improve equatorial illumination at the expense of irradiation at higher latitudes. These designs will be studied when new phase plates for the OMEGA Laser System, corresponding to the smaller target radii and custom beam profiles, are obtained. Implosion results from the combined set of high-intensity and high-IFAR implosions should yield valuable data to validate models of laser-energy deposition, heat conduction, nonuniformity growth, and fuel assembly in PD geometry.

  19. Status of the design of the ITER ECE diagnostic

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

    Taylor, G.; Austin, M. E.; Beno, J. H.; Danani, S.; Ellis, R. F.; Feder, R.; Hesler, J. L.; Hubbard, A. E.; Johnson, D. W.; Kumar, R.; et al

    2015-03-12

    In this study, the baseline design for the ITER electron cyclotron emission (ECE) diagnostic has entered the detailed preliminary design phase. Two plasma views are planned, a radial view and an oblique view that is sensitive to distortions in the electron momentum distribution near the average thermal momentum. Both views provide high spatial resolution electron temperature profiles when the momentum distribution remains Maxwellian. The ECE diagnostic system consists of the front-end optics, including two 1000 K calibration sources, in equatorial port plug EP9, the 70-1000 GHz transmission system from the front-end to the diagnostics hall, and the ECE instrumentation inmore » the diagnostics hall. The baseline ECE instrumentation will include two Michelson interferometers that can simultaneously measure ordinary and extraordinary mode ECE from 70 to 1000 GHz, and two heterodyne radiometer systems, covering 122-230 GHz and 244-355 GHz. Significant design challenges include 1) developing highly-reliable 1000 K calibration sources and the associated shutters/mirrors, 2) providing compliant couplings between the front-end optics and the polarization splitter box that accommodate displacements of the vacuum vessel during plasma operations and bake out, 3) protecting components from damage due to stray ECH radiation and other intense millimeter wave emission and 4) providing the low-loss broadband transmission system.« less

  20. MHD Ballooning Instability in the Plasma Sheet

    SciTech Connect (OSTI)

    C.Z. Cheng; S. Zaharia

    2003-10-20

    Based on the ideal-MHD model the stability of ballooning modes is investigated by employing realistic 3D magnetospheric equilibria, in particular for the substorm growth phase. Previous MHD ballooning stability calculations making use of approximations on the plasma compressibility can give rise to erroneous conclusions. Our results show that without making approximations on the plasma compressibility the MHD ballooning modes are unstable for the entire plasma sheet where beta (sub)eq is greater than or equal to 1, and the most unstable modes are located in the strong cross-tail current sheet region in the near-Earth plasma sheet, which maps to the initial brightening location of the breakup arc in the ionosphere. However, the MHD beq threshold is too low in comparison with observations by AMPTE/CCE at X = -(8 - 9)R(sub)E, which show that a low-frequency instability is excited only when beq increases over 50. The difficulty is mitigated by considering the kinetic effects of ion gyrorad ii and trapped electron dynamics, which can greatly increase the stabilizing effects of field line tension and thus enhance the beta(sub)eq threshold [Cheng and Lui, 1998]. The consequence is to reduce the equatorial region of the unstable ballooning modes to the strong cross-tail current sheet region where the free energy associated with the plasma pressure gradient and magnetic field curvature is maximum.

  1. UV-visible spectroscopy of macrocyclic alkyl, nitrosyl and halide complexes of cobalt and rhodium. Experiment and calculation

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

    Hull, Emily A.; West, Aaron C.; Pestovsky, Oleg; Kristian, Kathleen E.; Ellern, Arkady; Dunne, James F.; Carraher, Jack M.; Bakac, Andreja; Windus, Theresa L.

    2015-01-22

    In this paper, transition metal complexes (NH3)5CoX2+ (X = CH3, Cl) and L(H2O)MX2+, where M = Rh or Co, X = CH3, NO, or Cl, and L is a macrocyclic N4 ligand are examined by both experiment and computation to better understand their electronic spectra and associated photochemistry. Specifically, irradiation into weak visible bands of nitrosyl and alkyl complexes (NH3)5CoCH32+ and L(H2O)MIIIX2+ (X = CH3 or NO) leads to photohomolysis that generates the divalent metal complex and ˙CH3 or ˙NO, respectively. On the other hand, when X = halide or NO2, visible light photolysis leads to dissociation of X– and/ormore » cis/trans isomerization. Computations show that visible bands for alkyl and nitrosyl complexes involve transitions from M–X bonding orbitals and/or metal d orbitals to M–X antibonding orbitals. In contrast, complexes with X = Cl or NO2 exhibit only d–d bands in the visible, so that homolytic cleavage of the M–X bond requires UV photolysis. UV-Vis spectra are not significantly dependent on the structure of the equatorial ligands, as shown by similar spectral features for (NH3)5CoCH32+ and L1(H2O)CoCH32+.« less

  2. Understanding predicted shifts in diazotroph biogeography using resource competition theory

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

    Dutkiewicz, S.; Ward, B. A.; Scott, J. R.; Follows, M. J.

    2014-05-19

    We examine the sensitivity of the biogeography of nitrogen fixers to a warming climate and increased aeolian iron deposition in the context of a global Earth System Model. We employ concepts from Resource Ratio Theory to provide a simplifying and transparent interpretation of the results. First we demonstrate that a set of clearly defined, easily diagnosed provinces are consistent with the theory. Using the framework we show that the regions most vulnerable to province shifts and changes in diazotroph biogeography are the Equatorial and South Pacific, and central Atlantic. Warmer and dustier climates favor diazotrophs due to an increase inmore » the ratio of supply rate of iron to fixed nitrogen. The analysis suggests that monitoring of real world province boundaries, indicated by transitions in surface nutrient concentrations, would provide a clear and easily interpreted indicator of ongoing global change. We suggest that the emergent provinces could be a standard diagnostic for global change models, allowing for rapid and transparent interpretation and comparison of model predictions and the underlying mechanisms.« less

  3. Understanding predicted shifts in diazotroph biogeography using resource competition theory

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

    Dutkiewicz, S.; Ward, B. A.; Scott, J. R.; Follows, M. J.

    2014-10-08

    We examine the sensitivity of the biogeography of nitrogen fixers to a warming climate and increased aeolian iron deposition in the context of a global earth system model. We employ concepts from the resource-ratio theory to provide a simplifying and transparent interpretation of the results. First we demonstrate that a set of clearly defined, easily diagnosed provinces are consistent with the theory. Using this framework we show that the regions most vulnerable to province shifts and changes in diazotroph biogeography are the equatorial and South Pacific, and central Atlantic. Warmer and dustier climates favor diazotrophs due to an increase inmore » the ratio of supply rate of iron to fixed nitrogen. We suggest that the emergent provinces could be a standard diagnostic for global change models, allowing for rapid and transparent interpretation and comparison of model predictions and the underlying mechanisms. The analysis suggests that monitoring of real world province boundaries, indicated by transitions in surface nutrient concentrations, would provide a clear and easily interpreted indicator of ongoing global change.« less

  4. Generation mechanism of the slowly drifting narrowband structure in the type IV solar radio bursts observed by AMATERAS

    SciTech Connect (OSTI)

    Katoh, Y.; Nishimura, Y.; Kumamoto, A.; Ono, T.; Iwai, K.; Misawa, H.; Tsuchiya, F.

    2014-05-20

    We investigate the type IV burst event observed by AMATERAS on 2011 June 7, and reveal that the main component of the burst was emitted from the plasmoid eruption identified in the EUV images of the Solar Dynamics Observatory (SDO)/AIA. We show that a slowly drifting narrowband structure (SDNS) appeared in the burst's spectra. Using statistical analysis, we reveal that the SDNS appeared for a duration of tens to hundreds of milliseconds and had a typical bandwidth of 3 MHz. To explain the mechanism generating the SDNS, we propose wave-wave coupling between Langmuir waves and whistler-mode chorus emissions generated in a post-flare loop, which were inferred from the similarities in the plasma environments of a post-flare loop and the equatorial region of Earth's inner magnetosphere. We assume that a chorus element with a rising tone is generated at the top of a post-flare loop. Using the magnetic field and plasma density models, we quantitatively estimate the expected duration of radio emissions generated from coupling between Langmuir waves and chorus emissions during their propagation in the post-flare loop, and we find that the observed duration and bandwidth properties of the SDNS are consistently explained by the proposed generation mechanism. While observations in the terrestrial magnetosphere show that the chorus emissions are a group of large-amplitude wave elements generated naturally and intermittently, the mechanism proposed in the present study can explain both the intermittency and the frequency drift in the observed spectra.

  5. African oil plays

    SciTech Connect (OSTI)

    Clifford, A.J. )

    1989-09-01

    The vast continent of Africa hosts over eight sedimentary basins, covering approximately half its total area. Of these basins, only 82% have entered a mature exploration phase, 9% have had little or no exploration at all. Since oil was first discovered in Africa during the mid-1950s, old play concepts continue to bear fruit, for example in Egypt and Nigeria, while new play concepts promise to become more important, such as in Algeria, Angola, Chad, Egypt, Gabon, and Sudan. The most exciting developments of recent years in African oil exploration are: (1) the Gamba/Dentale play, onshore Gabon; (2) the Pinda play, offshore Angola; (3) the Lucula/Toca play, offshore Cabinda; (4) the Metlaoui play, offshore Libya/Tunisia; (5) the mid-Cretaceous sand play, Chad/Sudan; and (6) the TAG-I/F6 play, onshore Algeria. Examples of these plays are illustrated along with some of the more traditional oil plays. Where are the future oil plays likely to develop No doubt, the Saharan basins of Algeria and Libya will feature strongly, also the presalt of Equatorial West Africa, the Central African Rift System and, more speculatively, offshore Ethiopia and Namibia, and onshore Madagascar, Mozambique, and Tanzania.

  6. A design approach for improving the performance of single-grid planar retarding potential analyzers

    SciTech Connect (OSTI)

    Davidson, R. L.; Earle, G. D. [William B. Hanson Center for Space Sciences, University of Texas at Dallas, 800 W. Campbell Rd. WT15, Richardson, Texas 75080 (United States)

    2011-01-15

    Planar retarding potential analyzers (RPAs) have a long flight history and have been included on numerous spaceflight missions including Dynamics Explorer, the Defense Meteorological Satellite Program, and the Communications/Navigation Outage Forecast System. RPAs allow for simultaneous measurement of plasma composition, density, temperature, and the component of the velocity vector normal to the aperture plane. Internal conductive grids are used to approximate ideal potential planes within the instrument, but these grids introduce perturbations to the potential map inside the RPA and cause errors in the measurement of the parameters listed above. A numerical technique is presented herein for minimizing these grid errors for a specific mission by varying the depth and spacing of the grid wires. The example mission selected concentrates on plasma dynamics near the sunset terminator in the equatorial region. The international reference ionosphere model is used to discern the average conditions expected for this mission, and a numerical model of the grid-particle interaction is used to choose a grid design that will best fulfill the mission goals.

  7. Compact planetary systems perturbed by an inclined companion. I. Vectorial representation of the secular model

    SciTech Connect (OSTI)

    Bou, Gwenal; Fabrycky, Daniel C.

    2014-07-10

    The non-resonant secular dynamics of compact planetary systems are modeled by a perturbing function that is usually expanded in eccentricity and absolute inclination with respect to the invariant plane. Here, the expressions are given in a vectorial form which naturally leads to an expansion in eccentricity and mutual inclination. The two approaches are equivalent in most cases, but the vectorial one is specially designed for those cases where an entire quasi-coplanar system tilts to a large degree. Moreover, the vectorial expressions of the Hamiltonian and of the equations of motion are slightly simpler than those given in terms of the usual elliptical elements. We also provide the secular perturbing function in vectorial form expanded in semi-major axis ratio allowing for arbitrary eccentricities and inclinations. The interaction between the equatorial bulge of a central star and its planets is also provided, as is the relativistic periapse precession of any planet induced by the central star. We illustrate the use of this representation to follow the secular oscillations of the terrestrial planets of the solar system and for Kozai cycles which may take place in exoplanetary systems.

  8. Status of the design of the ITER ECE diagnostic

    SciTech Connect (OSTI)

    Taylor, G.; Austin, M. E.; Beno, J. H.; Danani, S.; Feder, R.; Hesler, J. L.; Hubbard, A. E.; Johnson, D. W.; Kumar, R.; Pandya, H. K. B.; Roman, C.; Rowan, W. L.; Udintsev, V.; Vayakis, G.; Walsh, M.; Kubo, S.

    2015-03-12

    In this study, the baseline design for the ITER electron cyclotron emission (ECE) diagnostic has entered the detailed preliminary design phase. Two plasma views are planned, a radial view and an oblique view that is sensitive to distortions in the electron momentum distribution near the average thermal momentum. Both views provide high spatial resolution electron temperature profiles when the momentum distribution remains Maxwellian. The ECE diagnostic system consists of the front-end optics, including two 1000 K calibration sources, in equatorial port plug EP9, the 70-1000 GHz transmission system from the front-end to the diagnostics hall, and the ECE instrumentation in the diagnostics hall. The baseline ECE instrumentation will include two Michelson interferometers that can simultaneously measure ordinary and extraordinary mode ECE from 70 to 1000 GHz, and two heterodyne radiometer systems, covering 122-230 GHz and 244-355 GHz. Significant design challenges include 1) developing highly-reliable 1000 K calibration sources and the associated shutters/mirrors, 2) providing compliant couplings between the front-end optics and the polarization splitter box that accommodate displacements of the vacuum vessel during plasma operations and bake out, 3) protecting components from damage due to stray ECH radiation and other intense millimeter wave emission and 4) providing the low-loss broadband transmission system.

  9. Drake passage and central american seaway controls on the distribution of the oceanic carbon reservoir

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

    Fyke, Jeremy G.; D'Orgeville, Marc; Weaver, Andrew J.

    2015-05-01

    A coupled carbon/climate model is used to explore the impact of Drake Passage opening and Central American Seaway closure on the distribution of carbon in the global oceans. We find that gateway evolution likely played an important role in setting the modern day distribution of oceanic dissolved inorganic carbon (DIC), which is currently characterized by relatively low concentrations in the Atlantic ocean, and high concentrations in the Southern, Indian, and Pacific oceans. In agreement with previous studies, we find a closed Drake Passage in the presence of an open Central American Seaway results in suppressed Atlantic meridional overturning and enhancedmore » southern hemispheric deep convection. Opening of the Drake Passage triggers Antarctic Circumpolar Current flow and a weak Atlantic meridional overturning circulation (AMOC). Subsequent Central American Seaway closure reinforces the AMOC while also stagnating equatorial Pacific subsurface waters. These gateway-derived oceanographic changes are reflected in large shifts to the global distribution of DIC. An initially closed Drake Passage results in high DIC concentrations in the Atlantic and Arctic oceans, and lower DIC concentrations in the Pacific/Indian/Southern oceans. Opening Drake Passage reverses this gradient by lowering mid-depth Atlantic and Arctic DIC concentrations and raising deep Pacific/Indian/Southern Ocean DIC concentrations. Central American Seaway closure further reinforces this trend through additional Atlantic mid-depth DIC decreases, as well as Pacific mid-depth DIC concentration increases, with the net effect being a transition to a modern distribution of oceanic DIC.« less

  10. Frequency sweep rates of rising tone electromagnetic ion cyclotron waves: Comparison between nonlinear theory and Cluster observation

    SciTech Connect (OSTI)

    He, Zhaoguo; Zong, Qiugang Wang, Yongfu; Liu, Siqing; Lin, Ruilin; Shi, Liqin

    2014-12-15

    Resonant pitch angle scattering by electromagnetic ion cyclotron (EMIC) waves has been suggested to account for the rapid loss of ring current ions and radiation belt electrons. For the rising tone EMIC wave (classified as triggered EMIC emission), its frequency sweep rate strongly affects the efficiency of pitch-angle scattering. Based on the Cluster observations, we analyze three typical cases of rising tone EMIC waves. Two cases locate at the nightside (22.3 and 22.6 magnetic local time (MLT)) equatorial region and one case locates at the duskside (18MLT) higher magnetic latitude (??=?9.3) region. For the three cases, the time-dependent wave amplitude, cold electron density, and cold ion density ratio are derived from satellite data; while the ambient magnetic field, thermal proton perpendicular temperature, and the wave spectral can be directly provided by observation. These parameters are input into the nonlinear wave growth model to simulate the time-frequency evolutions of the rising tones. The simulated results show good agreements with the observations of the rising tones, providing further support for the previous finding that the rising tone EMIC wave is excited through the nonlinear wave growth process.

  11. A new equation of state with light nuclei and their weak interactions in core-collapse supernova simulations

    SciTech Connect (OSTI)

    Furusawa, Shun; Yamada, Shoichi [Waseda University, 3-4-1, Okubo, Shinjuku, Tokyo 169-8555 (Japan); Nagakura, Hiroki [Yukawa Institute for Theoretical Physics, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto, 606-8502 (Japan); Sumiyoshi, Kohsuke [Numazu College of Technology, Ooka 3600, Numazu, Shizuoka 410-8501 (Japan); Suzuki, Hideyuki [Faculty of Science and Technology, Tokyo University of Science, Yamazaki 2641, Noda, Chiba 278-8510 (Japan)

    2014-05-02

    We perform numerical experiments to investigate the influence of inelastic neutrino reactions with light nuclei on the standing accretion shock instability. The time evolutions of shock waves are calculated with a simple light-bulb approximation for the neutrino transport and a multi-nuclei equation of state. The neutrino absorptions and inelastic interactions with deuterons, tritons, helions and alpha particles are taken into account in the hydrodynamical simulations in addition to the ordinary charged-current interactions with nucleons. Axial symmetry is assumed but no equatorial symmetry is imposed. We show that the heating rates of deuterons reach as high as ? 10% of those of nucleons around the bottom of the gain region. On the other hands, alpha particles heat the matter near the shock wave, which is important when the shock wave expands and density and temperature of matter become low. It is also found that the models with heating by light nuclei have different evolutions from those without it in non-linear evolution phase. The matter in the gain region has various densities and temperatures and there appear regions that are locally rich in deuterons and alpha particles. These results indicate that the inelastic reactions of light nuclei, especially deuterons, should be incorporated in the simulations of core-collapse supernovae.

  12. Final Report for DOE contract DE-FG02-98ER62609

    SciTech Connect (OSTI)

    Webb, Thompson, III

    2012-08-20

    Several publications document, analyze, and map the paleoclimatic data available for the last glacial maximum (LGM) 21,000 years ago. Data coverage is fairly extensive for North America, Eurasia, and Africa. The data show much lower temperatures for that time in earth history. These data were used to check climate model simulations for the LGM. Simulations forced by the CLIMAP SST for the LGM, where the west/east SST gradient across the Pacific is reduced compared to present, produce a reduction in the strength of the trade winds and a decrease in the west/east slope of the equatorial thermocline that is incompatible with thermocline depths newly inferred from foraminiferal assemblages. Stronger than-present trade winds, and a more realistic simulation of the thermocline slope, are produced when eastern Pacific SSTs are 2oC cooler than western Pacific SSTs. Sensitivity experiments for the model simulations of the LGM were also used to show which aspects of the climate boundary conditions produced various changes in model simulations for the LGM. An experiment which has the LGM ice sheets for the Northern Hemisphere but no Eurasian ice sheet shows that the downstream cooling in Asia is largely dependent on sea-ice growth in the North Atlantic, which is a product of the Laurentide ice sheet. Weaker Asian monsoons develop as a result of this downstream cooling, which is largest for low Laurentide ice sheets of large areal extent.

  13. The Status of USITER Diagnostic Port Plug Neutronics Analysis Using Attila

    SciTech Connect (OSTI)

    Feder, Russell; Youssef, Mahamoud; Klabacha, Jonathan

    2013-11-01

    USITER is one of seven partner domestic agencies (DA) contributing components to the ITER project. Four diagnostic port plug packages (two equatorial ports and two upper ports) will be engineered and fabricated by Princeton Plasma Physics Lab (PPPL). Diagnostic port plugs as illustrated in Fig. 1 are large primarily stainless steel structures that serve several roles on ITER. The port plugs are the primary vacuum seal and tritium confinement barriers for the vessel. The port plugs also house several plasma diagnostic systems and other machine service equipment. Finally, each port plug must shield high energy neutrons and gamma photons from escaping and creating radiological problems in maintenance areas behind the port plugs. The optimization of the balance between adequate shielding and the need for high performance, high throughput diagnostics systems is the focus of this paper. Neutronics calculations are also needed for assessing nuclear heating and nuclear damage in the port plug and diagnostic components. Attila, the commercially available discrete-ordinates software package, is used for all diagnostic port plug neutronics analysis studies at PPPL.

  14. Beat excitation of whistlers in the presence of field aligned irregularities in the ionosphere

    SciTech Connect (OSTI)

    Sodha, M. S.; Bhasin, Lalita; Tripathi, V. K. [Department of Education, Lucknow University, Lucknow, UP (India)

    2008-04-15

    In equatorial ionospheric plasma, embedded with a density ripple, a low frequency whistler can be resonantly excited by the nonlinear mixing of two high frequency radio waves launched from the ground at an oblique angle. A suitable configuration is where the earth magnetic field is along z (horizontal), ripple wave number q-vector parallel y (horizontal), and high frequency wave numbers are k-vector{sub 1}=k{sub 1} cos {theta}z+k{sub 1} sin {theta}(cos {phi}x+sin {phi}y), k-vector{sub 2}=-k{sub 2} cos {theta}z+k{sub 2} sin {theta}(cos {phi}x-sin {phi}y). Phase matching conditions are satisfied for large {theta} and small {phi}. The radio waves exert a ponderomotive force on electrons at the beat frequency imparting them an oscillatory velocity with a component perpendicular to the magnetic field. This velocity, in conjunction with the density ripple, produces a current that drives the whistler. The Ohmic nonlinearity is found to be relatively weaker in comparison to ponderomotive nonlinearity at higher heights. However in the E-region, this nonlinearity reinforces with the ponderomotive nonlinearity and can improve the whistler power generation.

  15. INFLATION OF A DIPOLE FIELD IN LABORATORY EXPERIMENTS: TOWARD AN UNDERSTANDING OF MAGNETODISK FORMATION IN THE MAGNETOSPHERE OF A HOT JUPITER

    SciTech Connect (OSTI)

    Antonov, V. M.; Boyarinsev, E. L.; Boyko, A. A.; Zakharov, Yu. P.; Melekhov, A. V.; Ponomarenko, A. G.; Posukh, V. G.; Shaikhislamov, I. F.; Khodachenko, M. L.; Lammer, H.

    2013-05-20

    Giant exoplanets at close orbits, or so-called hot Jupiters, are supposed to have an intensive escape of upper atmospheric material heated and ionized by the radiation of a host star. An interaction between outflowing atmospheric plasma and the intrinsic planetary magnetic dipole field leads to the formation of a crucial feature of a hot Jupiter's magnetosphere-an equatorial current-carrying magnetodisk. The presence of a magnetodisk has been shown to influence the topology of a hot Jupiter's magnetosphere and to change a standoff distance of the magnetopause. In this paper, the basic features of the formation of a hot Jupiter's magnetodisk are studied by means of a laboratory experiment. A localized central source produces plasma that expands outward from the surface of the dipole and inflates the magnetic field. The observed structure of magnetic fields, electric currents, and plasma density indicates the formation of a relatively thin current disk extending beyond the Alfvenic point. At the edge of the current disk, an induced magnetic field was found to be several times larger than the field of the initial dipole.

  16. Perturbation analysis of trapped-particle dynamics in axisymmetric dipole geometry

    SciTech Connect (OSTI)

    Duthoit, F.-X.; Brizard, A. J.; Peysson, Y.; Decker, J.

    2010-10-15

    The bounce-action-angle coordinates (J,{zeta}) for charged particles trapped in an axisymmetric dipole magnetic field are constructed by perturbation analysis. First, the lowest-order bounce-action-angle coordinates (J{sub 0},{zeta}{sub 0}) are derived for deeply trapped particles in the harmonic-oscillator approximation. Next, the Lie-transform perturbation method is used to derive higher-order anharmonic action-angle corrections (J=J{sub 0}+{epsilon}{sub t}J{sub 1}, {zeta}={zeta}{sub 0}+{epsilon}{sub t{zeta}1}), where the dimensionless parameter {epsilon}{sub t{identical_to}}(s{sub b}/r{sub e}){sup 2}<<1 is defined as the ratio of the turning-point distance |s{sub b}| (measured from the equator) along a magnetic field line labeled by the equatorial distance r{sub e}. Explicit expressions (with anharmonic corrections) for the canonical parallel coordinates s(J,{zeta}) and p{sub ||}(J,{zeta}) are presented, which satisfy the canonical identity {l_brace}s,p{sub ||{r_brace}{identical_to}}1. Lastly, analytical expressions for the bounce and drift frequencies (which include anharmonic corrections) yield excellent agreement with exact numerical results.

  17. Optimized boundary driven flows for dynamos in a sphere

    SciTech Connect (OSTI)

    Khalzov, I. V.; Brown, B. P.; Cooper, C. M.; Weisberg, D. B.; Forest, C. B. [Center for Magnetic Self Organization in Laboratory and Astrophysical Plasmas, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706 (United States)

    2012-11-15

    We perform numerical optimization of the axisymmetric flows in a sphere to minimize the critical magnetic Reynolds number Rm{sub cr} required for dynamo onset. The optimization is done for the class of laminar incompressible flows of von Karman type satisfying the steady-state Navier-Stokes equation. Such flows are determined by equatorially antisymmetric profiles of driving azimuthal (toroidal) velocity specified at the spherical boundary. The model is relevant to the Madison plasma dynamo experiment, whose spherical boundary is capable of differential driving of plasma in the azimuthal direction. We show that the dynamo onset in this system depends strongly on details of the driving velocity profile and the fluid Reynolds number Re. It is found that the overall lowest Rm{sub cr} Almost-Equal-To 200 is achieved at Re Almost-Equal-To 240 for the flow, which is hydrodynamically marginally stable. We also show that the optimized flows can sustain dynamos only in the range Rm{sub cr}

  18. Interstellar scintillation of the double pulsar J07373039

    SciTech Connect (OSTI)

    Rickett, B. J.; Coles, W. A.; Nava, C. F.; McLaughlin, M. A.; Ransom, S. M.; Camilo, F.; Ferdman, R. D.; Kramer, M.; Lyne, A. G.; Freire, P. C. C.; Stairs, I. H.

    2014-06-01

    We report a series of observations of the interstellar scintillation (ISS) of the double pulsar J07373039 over the course of 18 months. As in earlier work, the basic phenomenon is the variation in the ISS caused by the changing transverse velocities of each pulsar, the ionized interstellar medium (IISM), and the Earth. The transverse velocity of the binary system can be determined both by very long baseline interferometry and timing observations. The orbital velocity and inclination is almost completely determined from timing observations, but the direction of the orbital angular momentum is not known. Since the Earth's velocity is known, and can be compared with the orbital velocity by its effect on the timescale of the ISS, we can determine the orientation ? of the pulsar orbit with respect to equatorial coordinates (? = 65 2). We also resolve the ambiguity (i = 88.7 or 91.3) in the inclination of the orbit deduced from the measured Shapiro delay by our estimate i = 88.1 0.5. This relies on the analysis of the ISS over both frequency and time, and provides a model for the location, anisotropy, turbulence level, and transverse phase gradient of the IISM. We find that the IISM can be well-modeled during each observation, typically of a few orbital periods, but its turbulence level and mean velocity vary significantly over the 18 months.

  19. Line-driven winds revisited in the context of Be stars: ?-slow solutions with high k values

    SciTech Connect (OSTI)

    Silaj, J.; Jones, C. E.; Cur, M.

    2014-11-01

    The standard, or fast, solutions of m-CAK line-driven wind theory cannot account for slowly outflowing disks like the ones that surround Be stars. It has been previously shown that there exists another family of solutionsthe ?-slow solutionsthat is characterized by much slower terminal velocities and higher mass-loss rates. We have solved the one-dimensional m-CAK hydrodynamical equation of rotating radiation-driven winds for this latter solution, starting from standard values of the line force parameters (?, k, and ?), and then systematically varying the values of ? and k. Terminal velocities and mass-loss rates that are in good agreement with those found in Be stars are obtained from the solutions with lower ? and higher k values. Furthermore, the equatorial densities of such solutions are comparable to those that are typically assumed in ad hoc models. For very high values of k, we find that the wind solutions exhibit a new kind of behavior.

  20. Computational Studies of Physical Properties of Boron Carbide

    SciTech Connect (OSTI)

    Lizhi Ouyang

    2011-09-30

    The overall goal is to provide valuable insight in to the mechanisms and processes that could lead to better engineering the widely used boron carbide which could play an important role in current plight towards greener energy. Carbon distribution in boron carbide, which has been difficult to retrieve from experimental methods, is critical to our understanding of its structure-properties relation. For modeling disorders in boron carbide, we implemented a first principles method based on supercell approach within our G(P,T) package. The supercell approach was applied to boron carbide to determine its carbon distribution. Our results reveal that carbon prefers to occupy the end sites of the 3-atom chain in boron carbide and further carbon atoms will distribute mainly on the equatorial sites with a small percentage on the 3-atom chains and the apex sites. Supercell approach was also applied to study mechanical properties of boron carbide under uniaxial load. We found that uniaxial load can lead to amorphization. Other physical properties of boron carbide were calculated using the G(P,T) package.

  1. A TRANSMISSION SPECTRUM OF TITAN'S NORTH POLAR ATMOSPHERE FROM A SPECULAR REFLECTION OF THE SUN

    SciTech Connect (OSTI)

    Barnes, Jason W.; Clark, Roger N.; Sotin, Christophe; Buratti, Bonnie J.; dmkovics, Mt; Appr, Thomas; Rodriguez, Sebastien; Brown, Robert H.; Baines, Kevin H.; Le Moulic, Stphane; Nicholson, Philip D.

    2013-11-10

    Cassini/VIMS T85 observations of a solar specular reflection off of Kivu Lacus (87.4N 241.1E) provide an empirical transmission spectrum of Titan's atmosphere. Because this observation was acquired from short range (33,000 km), its intensity makes it visible within the 2.0, 2.7, and 2.8 ?m atmospheric windows in addition to the 5 ?m window where all previous specular reflections have been seen. The resulting measurement of the total one-way normal atmospheric optical depth (corresponding to haze scattering plus haze and gas absorption) provides strong empirical constraints on radiative transfer models. Using those models, we find that the total haze column abundance in our observation is 20% higher than the Huygens equatorial value. Ours is the first measurement in the 2-5 ?m wavelength range that probes all the way to the surface in Titan's arctic, where the vast majority of surface liquids are located. The specular technique complements other probes of atmospheric properties such as solar occultations and the direct measurements from Huygens. In breaking the degeneracy between surface and atmospheric absorptions, our measured optical depths will help to drive future calculations of deconvolved surface albedo spectra.

  2. Improved atmosphere-ocean coupled modeling in the tropics for climate prediction

    SciTech Connect (OSTI)

    Zhang, Minghua

    2015-01-01

    We investigated the initial development of the double ITCZ in the Community Climate System Model (CCSM Version 3) in the central Pacific. Starting from a resting initial condition of the ocean in January, the model developed a warm bias of sea-surface temperature (SST) in the central Pacific from 5oS to 10oS in the first three months. We found this initial bias to be caused by excessive surface shortwave radiation that is also present in the standalone atmospheric model. The initial bias is further amplified by biases in both surface latent heat flux and horizontal heat transport in the upper ocean. These biases are caused by the responses of surface winds to SST bias and the thermocline structure to surface wind curls. We also showed that the warming biases in surface solar radiation and latent heat fluxes are seasonally offset by cooling biases from reduced solar radiation after the austral summer due to cloud responses and in the austral fall due to enhanced evaporation when the maximum SST is closest to the equator. The warming biases from the dynamic heat transport by ocean currents however stay throughout all seasons once they are developed, which are eventually balanced by enhanced energy exchange and penetration of solar radiation below the mixed layer. Our results also showed that the equatorial cold tongue develops after the warm biases in the south central Pacific, and the overestimation of surface shortwave radiation recurs in the austral summer in each year.

  3. Final Activity Report: The Effects of Iron Complexing Ligands on the Long Term Ecosystem Response to Iron Enrichment of HNLC waters

    SciTech Connect (OSTI)

    Trick, Charles Gordon

    2013-07-30

    Substantial increases in the concentrations of the stronger of two Fe(III) complexing organic ligand classes measured during the mesoscale Fe enrichment studies IronEx II and SOIREE appeared to sharply curtailed Fe availability to diatoms and thus limited the efficiency of carbon sequestration to the deep. Detailed observations during IronEx II (equatorial Pacific Ocean) and SOIREE (Southern Ocean –Pacific sector) indicate that the diatoms began re-experiencing Fe stress even though dissolved Fe concentrations remained elevated in the patch. This surprising outcome likely is related to the observed increased concentrations of strong Fe(III)-complexing ligands in seawater. Preliminary findings from other studies indicate that diatoms may not readily obtain Fe from these chemical species whereas Fe bound by strong ligands appears to support growth of cyanobacteria and nanoflagellates. The difficulty in assessing the likelihood of these changes with in-situ mesoscale experiments is the extended monitoring period needed to capture the long-term trajectory of the carbon cycle. A more detailed understanding of Fe complexing ligand effects on long-term ecosystem structure and carbon cycling is essential to ascertain not only the effect of Fe enrichment on short-term carbon sequestration in the oceans, but also the potential effect of Fe enrichment in modifying ecosystem structure and trajectory.

  4. Drake passage and central american seaway controls on the distribution of the oceanic carbon reservoir

    SciTech Connect (OSTI)

    Fyke, Jeremy G.; D'Orgeville, Marc; Weaver, Andrew J.

    2015-05-01

    A coupled carbon/climate model is used to explore the impact of Drake Passage opening and Central American Seaway closure on the distribution of carbon in the global oceans. We find that gateway evolution likely played an important role in setting the modern day distribution of oceanic dissolved inorganic carbon (DIC), which is currently characterized by relatively low concentrations in the Atlantic ocean, and high concentrations in the Southern, Indian, and Pacific oceans. In agreement with previous studies, we find a closed Drake Passage in the presence of an open Central American Seaway results in suppressed Atlantic meridional overturning and enhanced southern hemispheric deep convection. Opening of the Drake Passage triggers Antarctic Circumpolar Current flow and a weak Atlantic meridional overturning circulation (AMOC). Subsequent Central American Seaway closure reinforces the AMOC while also stagnating equatorial Pacific subsurface waters. These gateway-derived oceanographic changes are reflected in large shifts to the global distribution of DIC. An initially closed Drake Passage results in high DIC concentrations in the Atlantic and Arctic oceans, and lower DIC concentrations in the Pacific/Indian/Southern oceans. Opening Drake Passage reverses this gradient by lowering mid-depth Atlantic and Arctic DIC concentrations and raising deep Pacific/Indian/Southern Ocean DIC concentrations. Central American Seaway closure further reinforces this trend through additional Atlantic mid-depth DIC decreases, as well as Pacific mid-depth DIC concentration increases, with the net effect being a transition to a modern distribution of oceanic DIC.

  5. Characteristics of surface current flow inferred from a global ocean current data set

    SciTech Connect (OSTI)

    Meehl, G.A.

    1982-06-01

    A seasonal global ocean-current data set (OCDS) digitized on a 5/sup 0/ grid from long-term mean shipdrift-derived currents from pilot charts is presented and described. Annual zonal means of v-component currents show subtropical convergence zones which moved closest to the equator during the respective winters in each hemisphere. Net annual v-component surface flow at the equator is northward. Zonally average u-component currents have greatest seasonal variance in the tropics with strongest westward currents in the winter hemisphere. An ensemble of ocean currents measured by buoys and current meters compares favorably with OCDS data in spite of widely varying time and space scales. The OCDS currents and directly measured currents are about twice as large as computed geostrophic currents. An analysis of equatorial Pacific currents suggests that dynamic topography and sea-level change indicative of the geostrophic flow component cannot be relied on solely to infer absolute strength of surface currents which include a strong Ekman component. Comparison of OCDS v-component currents and meridional transports predicted by Ekman theory shows agreement in the sign of transports in the midlatitudes and tropics in both hemispheres. Ekman depths required to scale OCDS v-component currents to computed Ekman transports are reasonable at most latitudes with layer depths deepening closer to the equator.

  6. The annual cycle in the tropical Pacific Ocean based on assimilated ocean data from 1983 to 1992

    SciTech Connect (OSTI)

    Smith, T.M.; Chelliah, M.

    1995-06-01

    An analysis of the tropical Pacific Ocean from January 1983 to December 1992 is used to describe the annual cycle, with the main focus on subsurface temperature variations. Some analysis of ocean-current variations are also considered. Monthly mean fields are generated by assimilation of surface and subsurface temperature observations from ships and buoys. Comparisons with observations show that the analysis reasonably describes large-scale ocean thermal variations. Ocean currents are not assimilated and do not compare as well with observations. However, the ocean-current variations in the analysis are qualitatively similar to the known variations given by others. The authors use harmonic analysis to separate the mean annual cycle and estimate its contribution to total variance. The analysis shows that in most regions the annual cycle of subsurface thermal variations is larger than surface variations and that these variations are associated with changes in the depth of the thermocline. The annual cycle accounts for most of the total surface variance poleward of about 10{degrees} latitude but accounts for much less surface and subsurface total variance near the equator. Large subsurface annual cycles occur near 10{degrees}N associated with shifts of the intertropical convergence zone and along the equator associated with the annual cycle of equatorial wind stress. The hemispherically asymmetric depths of the 20{degrees}C isotherms indicate that the large Southern Hemisphere warm pool, which extends to near the equator, may play an important role in thermal variations on the equator. 51 refs., 18 figs., 1 tab.

  7. A direct link between chorus emissions and pulsating aurora on timescales from milliseconds to minutes: A case study at subauroral latitudes

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

    Ozaki, Mitsunori; Yagitani, Satoshi; Sawai, Kaoru; Shiokawa, Kazuo; Miyoshi, Yoshizumi; Kataoka, Ryuho; Ieda, Akimasa; Ebihara, Yusuke; Connors, Martin; Schofield, Ian; et al

    2015-11-27

    A correlation was observed between chorus emissions and pulsating aurora (PA) from observations at Athabasca (L ≈ 4.3) in Canada at 9:00–9:20 UT on 7 February 2013, using an electron multiplying charge-coupled device camera and a VLF loop antenna with sampling rates of 110 Hz and 100 kHz, respectively. Pulsating aurora having a quasiperiodic variation in luminosity and a few hertz modulation was observed together with chorus emissions consisting of a group of successive rising-tone elements. The repetition period and modulation frequency of the PA are in good agreement with those of the modulated chorus. After 9:11 UT, the temporalmore » features of the aurora became aperiodic PA of indistinct modulation. Simultaneously, the rising-tone chorus turned into chorus emissions consisting of numerous rising-tone elements. The equatorial geomagnetic field inhomogeneity calculated using the Tsyganenko 2002 model shows a decreasing trend during the period. This result is consistent with nonlinear wave growth theory having a small geomagnetic field inhomogeneity, which contributes to a decrease in the threshold amplitude to trigger discrete chorus elements. As a result, these observations show a close connection between chorus emissions and PA on timescales from milliseconds for generation of discrete chorus elements on the microphysics of wave-particle interaction to minutes for the variations of the geomagnetic field inhomogeneity related with the substorm activity.« less

  8. ON THE SPIN-ORBIT MISALIGNMENT OF THE XO-3 EXOPLANETARY SYSTEM

    SciTech Connect (OSTI)

    Winn, Joshua N.; Johnson, John Asher; Fabrycky, Daniel; Esquerdo, Gil; Holman, Matthew J.; Howard, Andrew W.; Marcy, Geoffrey W.; Narita, Norio; Crossfield, Ian J.; Suto, Yasushi; Turner, Edwin L.

    2009-07-20

    We present photometric and spectroscopic observations of the 2009 February 2 transit of the exoplanet XO-3b. The new data show that the planetary orbital axis and stellar rotation axis are misaligned, as reported earlier by Hebrard and coworkers. We find the angle between the sky projections of the two axes to be 37.3 {+-} 3.7 deg., as compared to the previously reported value of 70 {+-} 15 deg. The significance of this discrepancy is unclear because there are indications of systematic effects. XO-3b is the first exoplanet known to have a highly inclined orbit relative to the equatorial plane of its parent star, and as such it may fulfill the predictions of some scenarios for the migration of massive planets into close-in orbits. We revisit the statistical analysis of spin-orbit alignment in hot-Jupiter systems. Assuming the stellar obliquities to be drawn from a single Rayleigh distribution, we find the mode of the distribution to be 13{sup +5}{sub -2} deg. However, it remains the case that a model representing two different migration channels-in which some planets are drawn from a perfectly aligned distribution and the rest are drawn from an isotropic distribution-is favored over a single Rayleigh distribution.

  9. THE TRANSIT INGRESS AND THE TILTED ORBIT OF THE EXTRAORDINARILY ECCENTRIC EXOPLANET HD 80606b

    SciTech Connect (OSTI)

    Winn, Joshua N.; Howard, Andrew W.; Marcy, Geoffrey W.; Johnson, John Asher; Gazak, J. Zachary; Starkey, Donn; Ford, Eric B.; Colon, Knicole D.; Reyes, Francisco; Nortmann, Lisa; Dreizler, Stefan; Odewahn, Stephen; Welsh, William F.; Kadakia, Shimonee; Vanderbei, Robert J.; Adams, Elisabeth R.; Lockhart, Matthew; Crossfield, Ian J.; Valenti, Jeff A.; Dantowitz, Ronald

    2009-10-01

    We present the results of a transcontinental campaign to observe the 2009 June 5 transit of the exoplanet HD 80606b. We report the first detection of the transit ingress, revealing the transit duration to be 11.64 +- 0.25 hr and allowing more robust determinations of the system parameters. Keck spectra obtained at midtransit exhibit an anomalous blueshift, giving definitive evidence that the stellar spin axis and planetary orbital axis are misaligned. The Keck data show that the projected spin-orbit angle lambda is between 32 deg. and 87 deg. with 68.3% confidence and between 14 deg. and 142 deg. with 99.73% confidence. Thus, the orbit of this planet is not only highly eccentric (e = 0.93) but is also tilted away from the equatorial plane of its parent star. A large tilt had been predicted, based on the idea that the planet's eccentric orbit was caused by the Kozai mechanism. Independently of the theory, it is worth noting that all three exoplanetary systems with known spin-orbit misalignments have massive planets on eccentric orbits, suggesting that those systems migrate through a different channel than lower mass planets on circular orbits.

  10. Ocean Carbon Cycle Data from the Joint Global Ocean Flux Study (JGOFS)

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

    The U.S. JGOFS program, a component of the U.S Global Change Research Program, grew out of the recommendations of a National Academy of Sciences workshop in 1984. An ambitious goal was set to understand the controls on the concentrations and fluxes of carbon and associated nutrients in the ocean. A new field of ocean biogeochemistry emerged with an emphasis on quality measurements of carbon system parameters and interdisciplinary field studies of the biological, chemical and physical process which control the ocean carbon cycle. U.S. JGOFS, ended in 2005 with the conclusion of the Synthesis and Modeling Project (SMP). Data are available throughout the U.S. JGOFS web site at http://usjgofs.whoi.edu/ and from the U.S. JGOFS Data System at http://usjgofs.whoi.edu/jg/dir/jgofs/. Major named segments of the project are: Bermuda Atlantic Time Series (BATS) Study, Hawaii Ocean Time-series (HOT) Study, Equatorial Pacific Process Study, North Atlantic Bloom Experiment (1989), Arabian Sea Process Study, and the Southern Ocean Process Study.

  11. The Molecular Architecture for the Intermediate Filaments of Hard α -Keratin Based on the Superlattice Data Obtained from a Study of Mammals Using Synchrotron Fibre Diffraction

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

    James, Veronica

    2011-01-01

    High- and low-angle X-ray diffraction studies of hard α -keratin have been studied, and various models have been proposed over the last 70 years. Most of these studies have been confined to one or two forms of alpha keratin. This high- and low-angle synchrotron fibre diffraction study extends the study to cover all available data for all known forms of hard α -keratin including hairs, fingernails, hooves, horn, and quills from mammals, marsupials, and a monotreme, and it confirms that the model proposed is universally acceptable for all mammals. A complete Bragg analysis of the meridional diffraction patterns, includingmore » multiple-time exposures to verify any weak reflections, verified the existence of a superlattice consisting of two infinite lattices and three finite lattices. An analysis of the equatorial patterns establishes the radii of the oligomeric levels of dimers, tetramers, and intermediate filaments (IFs) together with the centre to centre distance for the IFs, thus confirming the proposed helices within helices molecular architecture for hard α -keratin. The results verify that the structure proposed by Feughelman and James meets the criteria for a valid α -keratin structure.« less

  12. YOUNG PLANETARY NEBULAE: HUBBLE SPACE TELESCOPE IMAGING AND A NEW MORPHOLOGICAL CLASSIFICATION SYSTEM

    SciTech Connect (OSTI)

    Sahai, Raghvendra; Villar, Gregory G.; Morris, Mark R.

    2011-04-15

    Using Hubble Space Telescope images of 119 young planetary nebulae (PNs), most of which have not previously been published, we have devised a comprehensive morphological classification system for these objects. This system generalizes a recently devised system for pre-planetary nebulae, which are the immediate progenitors of PNs. Unlike previous classification studies, we have focused primarily on young PNs rather than all PNs, because the former best show the influences or symmetries imposed on them by the dominant physical processes operating at the first and primary stage of the shaping process. Older PNs develop instabilities, interact with the ambient interstellar medium, and are subject to the passage of photoionization fronts, all of which obscure the underlying symmetries and geometries imposed early on. Our classification system is designed to suffer minimal prejudice regarding the underlying physical causes of the different shapes and structures seen in our PN sample, however, in many cases, physical causes are readily suggested by the geometry, along with the kinematics that have been measured in some systems. Secondary characteristics in our system, such as ansae, indicate the impact of a jet upon a slower-moving, prior wind; a waist is the signature of a strong equatorial concentration of matter, whether it be outflowing or in a bound Keplerian disk, and point symmetry indicates a secular trend, presumably precession, in the orientation of the central driver of a rapid, collimated outflow.

  13. Sloan Digital Sky Survey II (SDSS-II) Supernova Data

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

    The Sloan Digital Sky Survey (SDSS) is a series of three interlocking imaging and spectroscopic surveys, carried out over an eight-year period with a dedicated 2.5m telescope located at Apache Point Observatory in Southern New Mexico. The SDSS Supernova Survey was one of those three components of SDSS and SDSS-II, a 3-year extension of the original SDSS that operated from July 2005 to July 2008. The Supernova Survey was a time-domain survey, involving repeat imaging of the same region of sky every other night, weather permitting. The primary scientific motivation was to detect and measure light curves for several hundred supernovae through repeat scans of the SDSS Southern equatorial stripe 82 (about 2.5? wide by ~120? long). Over the course of three 3-month campaigns SDSS-II SN discovered and measured multi-band lightcurves for ~500 spectroscopically confirmed Type Ia supernovae in the redshift range z=0.05-0.4. In addition, the project harvested a few hundred light curves for SNe Ia and discovered about 80 spectroscopically confirmed core-collapse supernovae (supernova types Ib/c and II).

  14. A direct link between chorus emissions and pulsating aurora on timescales from milliseconds to minutes: A case study at subauroral latitudes

    SciTech Connect (OSTI)

    Ozaki, Mitsunori; Yagitani, Satoshi; Sawai, Kaoru; Shiokawa, Kazuo; Miyoshi, Yoshizumi; Kataoka, Ryuho; Ieda, Akimasa; Ebihara, Yusuke; Connors, Martin; Schofield, Ian; Katoh, Yuto; Otsuka, Yuichi; Sunagawa, Naoki; Jordanova, Vania K.

    2015-11-27

    A correlation was observed between chorus emissions and pulsating aurora (PA) from observations at Athabasca (L ? 4.3) in Canada at 9:009:20 UT on 7 February 2013, using an electron multiplying charge-coupled device camera and a VLF loop antenna with sampling rates of 110 Hz and 100 kHz, respectively. Pulsating aurora having a quasiperiodic variation in luminosity and a few hertz modulation was observed together with chorus emissions consisting of a group of successive rising-tone elements. The repetition period and modulation frequency of the PA are in good agreement with those of the modulated chorus. After 9:11 UT, the temporal features of the aurora became aperiodic PA of indistinct modulation. Simultaneously, the rising-tone chorus turned into chorus emissions consisting of numerous rising-tone elements. The equatorial geomagnetic field inhomogeneity calculated using the Tsyganenko 2002 model shows a decreasing trend during the period. This result is consistent with nonlinear wave growth theory having a small geomagnetic field inhomogeneity, which contributes to a decrease in the threshold amplitude to trigger discrete chorus elements. As a result, these observations show a close connection between chorus emissions and PA on timescales from milliseconds for generation of discrete chorus elements on the microphysics of wave-particle interaction to minutes for the variations of the geomagnetic field inhomogeneity related with the substorm activity.

  15. Plutonium and americium behavior in coral atoll environments

    SciTech Connect (OSTI)

    Noshkin, V.E.; Wong, K.M.; Jokela, T.A.; Brunk, J.L.; Eagle, R.J.

    1984-02-01

    Inventories of /sup 239 +240/Pu and /sup 241/Am greatly in excess of global fallout levels persist in the benthic environments of Bikini and Enewetak Atolls. Quantities of /sup 239 +240/Pu and lesser amounts of /sup 241/Am are continuously mobilizing from these sedimentary reservoirs. The amount of /sup 239 +240/Pu mobilized to solution at any time represents 0.08 to 0.09% of the sediment inventories to a depth of 16 cm. The mobilized /sup 239 +240/Pu has solute-like characteristics and different valence states coexist in solution - the largest fraction of the soluble plutonium is in an oxidized form (+V,VI). The adsorption of plutonium to sediments is not completely reversible because of changes that occur in the relative amounts of the mixed oxidation states in solution with time. Further, any characteristics of /sup 239 +240/Pu described at one location may not necessarily be relevant in describing its behavior elsewhere following mobilization and migration. The relative amounts of /sup 241/Am to /sup 239 +240/Pu in the sedimentary deposits at Enewetak and Bikini may be altered in future years because of mobilization and radiological decay. Mobilization of /sup 239 +240/Pu is not a process unique to these atolls, and quantities in solution derived from sedimentary deposits can be found at other global sites. These studies in the equatorial Pacific have significance in assessing the long-term behavior of the transuranics in any marine environment. 22 references, 1 figure, 13 tables.

  16. Spatial Variability of Surface Irradiance Measurements at the Manus ARM Site

    SciTech Connect (OSTI)

    Riihimaki, Laura D.; Long, Charles N.

    2014-05-16

    The location of the Atmospheric Radiation Measurement (ARM) site on Manus island in Papua New Guinea was chosen because it is very close the coast, in a geographically at, near-sea level area of the island, minimizing the impact of local island effects on the meteorology of the measurements [Ackerman et al., 1999]. In this study, we confirm that the Manus site is in deed less impacted by the island meteorology than slightly inland by comparing over a year of broadband surface irradiance and ceilometer measurements and derived quantities at the standard Manus site and a second location 7 km away as part of the AMIE-Manus campaign. The two sites show statistically similar distributions of irradiance and other derived quantities for all wind directions except easterly winds, when the inland site is down wind from the standard Manus site. Under easterly wind conditions, which occur 17% of the time, there is a higher occurrence of cloudiness at the down wind site likely do to land heating and orographic effects. This increased cloudiness is caused by shallow, broken clouds often with bases around 700 m in altitude. While the central Manus site consistently measures a frequency of occurrence of low clouds (cloud base height less than 1200 m) about 25+4% regardless of wind direction, the AMIE site has higher frequencies of low clouds (38%) when winds are from the east. This increase in low, locally produced clouds causes an additional -20 W/m2 shortwave surface cloud radiative effect at the AMIE site in easterly conditions than in other meteorological conditions that exhibit better agreement between the two sites.

  17. TIME-RESOLVED 1-10 keV CRYSTAL SPECTROMETER FOR THE Z MACHINE AT SANDIA NATIONAL LABORATORIES

    SciTech Connect (OSTI)

    D. V. Morgan; S. Gardner; R. Liljestrand; M. Madlener; S. Slavin; M. Wu

    2003-06-01

    We have designed, fabricated, calibrated, and fielded a fast, time-resolved 1-10 keV crystal spectrometer to observe the evolution of wire pinch spectra at the Z machine at Sandia National Laboratories. The instrument has two convex cylindrical crystals (PET and KAP). Both crystals Bragg reflect x-rays into an array of ten silicon diodes, providing continuous spectral coverage in twenty channels from 1.0 to 10 keV. The spectral response of the instrument has been calibrated from 1.0 to 6.3 keV at beamline X8A at the National Synchrotron Light Source. The time response of the 1-mm2 silicon detectors was measured with the Pulsed X-ray Source at Bechtel Nevada's Los Alamos Operations, where 2-nanosecond full-width half-maximum (FWHM) waveforms with 700-picosecond rise times typically were observed. The spectrometer has been fielded recently on several experimental runs at the Z Machine. In this paper, we present the time-resolved spectra resulting from the implosions of double-nested tungsten wire arrays onto 5-mm diameter foam cylinders. We also show the results obtained for a double-nested stainless steel wire array with no target cylinder. The spectrometer was located at the end of a 7.1-meter beamline on line-of sight (LOS)21/22, at an angle 12{sup o} above the equatorial plane, and was protected from the debris field by a customized dual-slit fast valve. The soft detector channels below 2.0 keV recorded large signals at pinch time coinciding with signals recorded on vacuum x-ray diodes (XRDs). On experiment Z993, the spectrometer channels recorded a second pulse with a hard x-ray emission spectrum several nanoseconds after pinch time.

  18. Corotating solar wind structures and recurrent trains of enhanced diurnal variation in galactic cosmic rays

    SciTech Connect (OSTI)

    Yeeram, T.; Ruffolo, D.; Siz, A.; Kamyan, N.; Nutaro, T. E-mail: david.ruf@mahidol.ac.th E-mail: p_chang24@hotmail.com

    2014-04-01

    Data from the Princess Sirindhorn Neutron Monitor at Doi Inthanon, Thailand, with a vertical cutoff rigidity of 16.8 GV, were utilized to determine the diurnal anisotropy (DA) of Galactic cosmic rays (GCRs) near Earth during solar minimum conditions between 2007 November and 2010 November. We identified trains of enhanced DA over several days, which often recur after a solar rotation period (?27 days). By investigating solar coronal holes as identified from synoptic maps and solar wind parameters, we found that the intensity and anisotropy of cosmic rays are associated with the high-speed streams (HSSs) in the solar wind, which are in turn related to the structure and evolution of coronal holes. An enhanced DA was observed after the onset of some, but not all, HSSs. During time periods of recurrent trains, the DA was often enhanced or suppressed according to the sign of the interplanetary magnetic field B, which suggests a contribution from a mechanism involving a southward gradient in the GCR density, n, and a gradient anisotropy along B ?n. In one non-recurrent and one recurrent sequence, an HSS from an equatorial coronal hole was merged with that from a trailing mid-latitude extension of a polar coronal hole, and the slanted HSS structure in space with suppressed GCR density can account for the southward GCR gradient. We conclude that the gradient anisotropy is a source of temporary changes in the GCR DA under solar minimum conditions, and that the latitudinal GCR gradient can sometimes be explained by the coronal hole morphology.

  19. Universality of the acceleration due to gravity on the surface of a rapidly rotating neutron star

    SciTech Connect (OSTI)

    AlGendy, Mohammad; Morsink, Sharon M.

    2014-08-20

    On the surface of a rapidly rotating neutron star, the effective centrifugal force decreases the effective acceleration due to gravity (as measured in the rotating frame) at the equator while increasing the acceleration at the poles due to the centrifugal flattening of the star into an oblate spheroid. We compute the effective gravitational acceleration for relativistic rapidly rotating neutron stars and show that for a star with mass M, equatorial radius R{sub e} , and angular velocity ?, the deviations of the effective acceleration due to gravity from the nonrotating case take on a universal form that depends only on the compactness ratio M/R{sub e} , the dimensionless square of the angular velocity ?{sup 2}R{sub e}{sup 3}/GM, and the latitude on the star's surface. This dependence is universal, in that it has very little dependence on the neutron star's equation of state. The effective gravity is expanded in the slow-rotation limit to show the dependence on the effective centrifugal force, oblate shape of the star, and the quadrupole moment of the gravitational field. In addition, an empirical fit and simple formula for the effective gravity is found. We find that the increase in the acceleration due to gravity at the poles is of the same order of magnitude as the decrease in the effective acceleration due to gravity at the equator for all realistic value of mass, radius, and spin. For neutron stars that spin with frequencies near 600 Hz, the difference between the effective gravity at the poles and the equator is about 20%.

  20. ANALYTICAL SOLUTION FOR WAVES IN PLANETS WITH ATMOSPHERIC SUPERROTATION. I. ACOUSTIC AND INERTIA-GRAVITY WAVES

    SciTech Connect (OSTI)

    Peralta, J.; Lpez-Valverde, M. A.; Imamura, T.; Read, P. L.; Luz, D.; Piccialli, A.

    2014-07-01

    This paper is the first of a two-part study devoted to developing tools for a systematic classification of the wide variety of atmospheric waves expected on slowly rotating planets with atmospheric superrotation. Starting with the primitive equations for a cyclostrophic regime, we have deduced the analytical solution for the possible waves, simultaneously including the effect of the metric terms for the centrifugal force and the meridional shear of the background wind. In those cases when the conditions for the method of the multiple scales in height are met, these wave solutions are also valid when vertical shear of the background wind is present. A total of six types of waves have been found and their properties were characterized in terms of the corresponding dispersion relations and wave structures. In this first part, only waves that are direct solutions of the generic dispersion relation are studiedacoustic and inertia-gravity waves. Concerning inertia-gravity waves, we found that in the cases of short horizontal wavelengths, null background wind, or propagation in the equatorial region, only pure gravity waves are possible, while for the limit of large horizontal wavelengths and/or null static stability, the waves are inertial. The correspondence between classical atmospheric approximations and wave filtering has been examined too, and we carried out a classification of the mesoscale waves found in the clouds of Venus at different vertical levels of its atmosphere. Finally, the classification of waves in exoplanets is discussed and we provide a list of possible candidates with cyclostrophic regimes.

  1. TITAN'S TRANSPORT-DRIVEN METHANE CYCLE

    SciTech Connect (OSTI)

    Mitchell, Jonathan L.

    2012-09-10

    The mechanisms behind the occurrence of large cloud outbursts and precipitation on Titan have been disputed. A global- and annual-mean estimate of surface fluxes indicated only 1% of the insolation, or {approx}0.04 W m{sup -2}, is exchanged as sensible and/or latent fluxes. Since these fluxes are responsible for driving atmospheric convection, it has been argued that moist convection should be quite rare and precipitation even rarer, even if evaporation globally dominates the surface-atmosphere energy exchange. In contrast, climate simulations indicate substantial cloud formation and/or precipitation. We argue that the top-of-atmosphere (TOA) radiative imbalance is diagnostic of horizontal heat transport by Titan's atmosphere, and thus constrains the strength of the methane cycle. Simple calculations show the TOA radiative imbalance is {approx}0.5-1 W m{sup -2} in Titan's equatorial region, which implies 2-3 MW of latitudinal heat transport by the atmosphere. Our simulation of Titan's climate suggests this transport may occur primarily as latent heat, with net evaporation at the equator and net accumulation at higher latitudes. Thus, the methane cycle could be 10-20 times previous estimates. Opposing seasonal transport at solstices, compensation by sensible heat transport, and focusing of precipitation by large-scale dynamics could further enhance the local, instantaneous strength of Titan's methane cycle by a factor of several. A limited supply of surface liquids in regions of large surface radiative imbalance may throttle the methane cycle, and if so, we predict more frequent large storms over the lakes district during Titan's northern summer.

  2. THE INFRARED PROPERTIES OF SOURCES MATCHED IN THE WISE ALL-SKY AND HERSCHEL ATLAS SURVEYS

    SciTech Connect (OSTI)

    Bond, Nicholas A.; Benford, Dominic J.; Gardner, Jonathan P.; Amblard, Alexandre; Blain, Andrew W.; Dunne, Loretta; Maddox, Steve J.; Hoyos, Carlos; Bourne, Nathan; Smith, Daniel J. B.; Bonfield, David; Baes, Maarten; Bridge, Carrie; Buttiglione, Sara; De Zotti, Gianfranco; Cava, Antonio; Clements, David; Cooray, Asantha; Dariush, Ali; and others

    2012-05-01

    We describe the infrared properties of sources detected over {approx}36 deg{sup 2} of sky in the GAMA 15 hr equatorial field, using data from both the Herschel Astrophysical Terahertz Large-Area Survey (H-ATLAS) and Wide-field Infrared Survey (WISE). With 5{sigma} point-source depths of 34 and 0.048 mJy at 250 {mu}m and 3.4 {mu}m, respectively, we are able to identify 50.6% of the H-ATLAS sources in the WISE survey, corresponding to a surface density of {approx}630 deg{sup -2}. Approximately two-thirds of these sources have measured spectroscopic or optical/near-IR photometric redshifts of z < 1. For sources with spectroscopic redshifts at z < 0.3, we find a linear correlation between the infrared luminosity at 3.4 {mu}m and that at 250 {mu}m, with {+-}50% scatter over {approx}1.5 orders of magnitude in luminosity, {approx}10{sup 9}-10{sup 10.5} L{sub Sun }. By contrast, the matched sources without previously measured redshifts (r {approx}> 20.5) have 250-350 {mu}m flux density ratios which suggest either high-redshift galaxies (z {approx}> 1.5) or optically faint low-redshift galaxies with unusually low temperatures (T {approx}< 20). Their small 3.4-250 {mu}m flux ratios favor a high-redshift galaxy population, as only the most actively star-forming galaxies at low redshift (e.g., Arp 220) exhibit comparable flux density ratios. Furthermore, we find a relatively large active galactic nucleus fraction ({approx}30%) in a 12 {mu}m flux-limited subsample of H-ATLAS sources, also consistent with there being a significant population of high-redshift sources in the no-redshift sample.

  3. Synthesis, Improved Antisense Activity and Structural Rationale for the Divergent RNA Affinities of 3;#8242;-Fluoro Hexitol Nucleic Acid (FHNA and Ara-FHNA) Modified Oligonucleotides

    SciTech Connect (OSTI)

    Egli, Martin; Pallan, Pradeep S.; Allerson, Charles R.; Prakash, Thazha P.; Berdeja, Andres; Yu, Jinghua; Lee, Sam; Watt, Andrew; Gaus, Hans; Bhat, Balkrishen; Swayze, Eric E.; Seth, Punit P.

    2012-03-16

    The synthesis, biophysical, structural, and biological properties of both isomers of 3'-fluoro hexitol nucleic acid (FHNA and Ara-FHNA) modified oligonucleotides are reported. Synthesis of the FHNA and Ara-FHNA thymine phosphoramidites was efficiently accomplished starting from known sugar precursors. Optimal RNA affinities were observed with a 3'-fluorine atom and nucleobase in a trans-diaxial orientation. The Ara-FHNA analog with an equatorial fluorine was found to be destabilizing. However, the magnitude of destabilization was sequence-dependent. Thus, the loss of stability is sharply reduced when Ara-FHNA residues were inserted at pyrimidine-purine (Py-Pu) steps compared to placement within a stretch of pyrimidines (Py-Py). Crystal structures of A-type DNA duplexes modified with either monomer provide a rationalization for the opposing stability effects and point to a steric origin of the destabilization caused by the Ara-FHNA analog. The sequence dependent effect can be explained by the formation of an internucleotide C-F {hor_ellipsis} H-C pseudo hydrogen bond between F3' of Ara-FHNA and C8-H of the nucleobase from the 3'-adjacent adenosine that is absent at Py-Py steps. In animal experiments, FHNA-modified antisense oligonucleotides formulated in saline showed a potent downregulation of gene expression in liver tissue without producing hepatotoxicity. Our data establish FHNA as a useful modification for antisense therapeutics and also confirm the stabilizing influence of F(Py) {hor_ellipsis} H-C(Pu) pseudo hydrogen bonds in nucleic acid structures.

  4. Sparkling extreme-ultraviolet bright dots observed with Hi-C

    SciTech Connect (OSTI)

    Rgnier, S.; Alexander, C. E.; Walsh, R. W.; Winebarger, A. R.; Cirtain, J.; Golub, L.; Korreck, K. E.; Weber, M.; Mitchell, N.; Platt, S.; De Pontieu, B.; Title, A.; Kobayashi, K.; Kuzin, S.; DeForest, C. E.

    2014-04-01

    Observing the Sun at high time and spatial scales is a step toward understanding the finest and fundamental scales of heating events in the solar corona. The high-resolution coronal (Hi-C) instrument has provided the highest spatial and temporal resolution images of the solar corona in the EUV wavelength range to date. Hi-C observed an active region on 2012 July 11 that exhibits several interesting features in the EUV line at 193 . One of them is the existence of short, small brightenings 'sparkling' at the edge of the active region; we call these EUV bright dots (EBDs). Individual EBDs have a characteristic duration of 25 s with a characteristic length of 680 km. These brightenings are not fully resolved by the SDO/AIA instrument at the same wavelength; however, they can be identified with respect to the Hi-C location of the EBDs. In addition, EBDs are seen in other chromospheric/coronal channels of SDO/AIA, which suggests a temperature between 0.5 and 1.5 MK. Based on their frequency in the Hi-C time series, we define four different categories of EBDs: single peak, double peak, long duration, and bursty. Based on a potential field extrapolation from an SDO/HMI magnetogram, the EBDs appear at the footpoints of large-scale, trans-equatorial coronal loops. The Hi-C observations provide the first evidence of small-scale EUV heating events at the base of these coronal loops, which have a free magnetic energy of the order of 10{sup 26} erg.

  5. Laplace plane modifications arising from solar radiation pressure

    SciTech Connect (OSTI)

    Rosengren, Aaron J.; Scheeres, Daniel J.

    2014-05-01

    The dynamical effects of solar radiation pressure (SRP) in the solar system have been rigorously studied since the early 1900s. This non-gravitational perturbation plays a significant role in the evolution of dust particles in circumplanetary orbits, as well as in the orbital motion about asteroids and comets. For gravitationally dominated orbits, SRP is negligible and the resulting motion is largely governed by the oblateness of the primary and the attraction of the Sun. The interplay between these gravitational perturbations gives rise to three mutually perpendicular planes of equilibrium for circular satellite orbits. The classical Laplace plane lies between the equatorial and orbital planes of the primary, and is the mean reference plane about whose axis the pole of a satellite's orbit precesses. From a previously derived solution for the secular motion of an orbiter about a small body in a SRP dominated environment, we find that SRP acting alone will cause an initially circular orbit to precess around the pole of the primary's heliocentric orbital plane. When the gravitational and non-gravitational perturbations act in concert, the resulting equilibrium planes turn out to be qualitatively different, in some cases, from those obtained without considering the radiation pressure. The warping of the surfaces swept out by the modified equilibria as the semi-major axis varies depends critically on the cross-sectional area of the body exposed. These results, together with an adiabatic invariance argument on Poynting-Robertson drag, provide a natural qualitative explanation for the initial albedo dichotomy of Saturn's moon, Iapetus.

  6. Multi-dimensional simulations of the expanding supernova remnant of SN 1987A

    SciTech Connect (OSTI)

    Potter, T. M.; Staveley-Smith, L. [International center for Radio Astronomy Research (ICRAR) M468, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009 (Australia); Reville, B. [Center for Plasma Physics, Queen's University Belfast, University Road, Belfast BT7 1NN (United Kingdom); Ng, C.-Y. [Department of Physics, The University of Hong Kong, Pokfulam Road (Hong Kong); Bicknell, G. V.; Sutherland, R. S. [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 0200 (Australia); Wagner, A. Y., E-mail: tobympotter@gmail.com [Center for Computational Sciences, Tsukuba University, Tsukuba, Ibaraki, 305-8577 (Japan)

    2014-10-20

    The expanding remnant from SN 1987A is an excellent laboratory for investigating the physics of supernovae explosions. There is still a large number of outstanding questions, such as the reason for the asymmetric radio morphology, the structure of the pre-supernova environment, and the efficiency of particle acceleration at the supernova shock. We explore these questions using three-dimensional simulations of the expanding remnant between days 820 and 10,000 after the supernova. We combine a hydrodynamical simulation with semi-analytic treatments of diffusive shock acceleration and magnetic field amplification to derive radio emission as part of an inverse problem. Simulations show that an asymmetric explosion, combined with magnetic field amplification at the expanding shock, is able to replicate the persistent one-sided radio morphology of the remnant. We use an asymmetric Truelove and McKee progenitor with an envelope mass of 10 M {sub ?} and an energy of 1.5 10{sup 44} J. A termination shock in the progenitor's stellar wind at a distance of 0.''43-0.''51 provides a good fit to the turn on of radio emission around day 1200. For the H II region, a minimum distance of 0.''63 0.''01 and maximum particle number density of (7.11 1.78) 10{sup 7} m{sup 3} produces a good fit to the evolving average radius and velocity of the expanding shocks from day 2000 to day 7000 after explosion. The model predicts a noticeable reduction, and possibly a temporary reversal, in the asymmetric radio morphology of the remnant after day 7000, when the forward shock left the eastern lobe of the equatorial ring.

  7. Spectral and morphological analysis of the remnant of supernova 1987A with ALMA and ATCA

    SciTech Connect (OSTI)

    Zanardo, Giovanna; Staveley-Smith, Lister [International Centre for Radio Astronomy Research (ICRAR), M468, University of Western Australia, Crawley, WA 6009 (Australia); Indebetouw, Remy; Chevalier, Roger A. [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904 (United States); Matsuura, Mikako; Barlow, Michael J. [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom); Gaensler, Bryan M. [Australian Research Council, Centre of Excellence for All-sky Astrophysics (CAASTRO) (Australia); Fransson, Claes; Lundqvist, Peter [Department of Astronomy, Oskar Klein Center, Stockholm University, AlbaNova, SE-106 91 Stockholm (Sweden); Manchester, Richard N. [CSIRO Astronomy and Space Science, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710 (Australia); Baes, Maarten [Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, B-9000 Gent (Belgium); Kamenetzky, Julia R. [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721-0065 (United States); Laki?evi?, Maa [Institute for the Environment, Physical Sciences and Applied Mathematics, Lennard-Jones Laboratories, Keele University, Staffordshire ST5 5BG (United Kingdom); Marcaide, Jon M. [Departamento de Astronoma, Universidad de Valencia, C/Dr. Moliner 50, E-46100 Burjassot (Spain); Mart-Vidal, Ivan [Department of Earth and Space Sciences, Chalmers University of Technology, Onsala Space Observatory, SE-439 92 Onsala (Sweden); Meixner, Margaret [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Ng, C.-Y. [Department of Physics, University of Hong Kong, Pokfulam Road, Hong Kong (China); Park, Sangwook, E-mail: giovanna.zanardo@gmail.com [Department of Physics, University of Texas at Arlington, 108 Science Hall, Box 19059, Arlington, TX 76019 (United States); and others

    2014-12-01

    We present a comprehensive spectral and morphological analysis of the remnant of supernova (SN) 1987A with the Australia Telescope Compact Array (ATCA) and the Atacama Large Millimeter/submillimeter Array (ALMA). The non-thermal and thermal components of the radio emission are investigated in images from 94 to 672 GHz (? 3.2 mm to 450 ?m), with the assistance of a high-resolution 44 GHz synchrotron template from the ATCA, and a dust template from ALMA observations at 672 GHz. An analysis of the emission distribution over the equatorial ring in images from 44 to 345 GHz highlights a gradual decrease of the east-to-west asymmetry ratio with frequency. We attribute this to the shorter synchrotron lifetime at high frequencies. Across the transition from radio to far infrared, both the synchrotron/dust-subtracted images and the spectral energy distribution (SED) suggest additional emission beside the main synchrotron component (S {sub ?}??{sup 0.73}) and the thermal component originating from dust grains at T ? 22 K. This excess could be due to free-free flux or emission from grains of colder dust. However, a second flat-spectrum synchrotron component appears to better fit the SED, implying that the emission could be attributed to a pulsar wind nebula (PWN). The residual emission is mainly localized west of the SN site, as the spectral analysis yields 0.4 ? ? ? 0.1 across the western regions, with ? ? 0 around the central region. If there is a PWN in the remnant interior, these data suggest that the pulsar may be offset westward from the SN position.

  8. Generation of kinetic Alfven waves in the high-latitude near-Earth magnetotail: A global hybrid simulation

    SciTech Connect (OSTI)

    Guo, Zhifang; Hong, Minghua; Du, Aimin; Lin, Yu; Wang, Xueyi; Wu, Mingyu; Lu, Quanming

    2015-02-15

    In this paper, effects of a fast flow in the tail plasma sheet on the generation of kinetic Alfven waves (KAWs) in the high-latitude of the near-Earth magnetotail are investigated by performing a two-dimensional (2-D) global-scale hybrid simulation, where the plasma flow is initialized by the EB drift near the equatorial plane due to the existence of the dawn-dusk convection electric field. It is found that firstly, the plasma sheet becomes thinned and the dipolarization of magnetic field appears around (x,z)=(?10.5R{sub E},0.3R{sub E}), where R{sub E} is the radius of the Earth. Then, shear Alfven waves are excited in the plasma sheet, and the strong earthward flow is braked by the dipole-like magnetic field. These waves propagate along the magnetic field lines toward the polar regions later. Subsequently, KAWs with k{sub ?}?k{sub ?} are generated in the high-latitude magnetotail due to the existence of the non-uniformity of the magnetic field and density in the polar regions. The ratio of the electric field to the magnetic field in these waves is found to obey the relation (?E{sub z})/(?B{sub y}?)??/k{sub ?} of KAWs. Our simulation provides a mechanism for the generation of the observed low-frequency shear Alfven waves in the plasma sheet and kinetic Alfven waves in the high-latitude near-Earth magnetotail, whose source is suggested to be the flow braking in the low-latitude plasma sheet.

  9. Bounce- and MLT-averaged diffusion coefficients in a physics-based magnetic field geometry obtained from RAM-SCB for the March 17 2013 storm

    SciTech Connect (OSTI)

    Zhao, Lei; Yu, Yiqun; Delzanno, Gian Luca; Jordanova, Vania K.

    2015-04-01

    Local acceleration via whistler wave and particle interaction plays a significant role in particle dynamics in the radiation belt. In this work we explore gyro-resonant wave-particle interaction and quasi-linear diffusion in different magnetic field configurations related to the March 17 2013 storm. We consider the Earth's magnetic dipole field as a reference and compare the results against non-dipole field configurations corresponding to quiet and stormy conditions. The latter are obtained with the ring current-atmosphere interactions model with a self-consistent magnetic field RAM-SCB, a code that models the Earth's ring current and provides a realistic modeling of the Earth's magnetic field. By applying quasi-linear theory, the bounce- and MLT-averaged electron pitch angle, mixed term, and energy diffusion coefficients are calculated for each magnetic field configuration. For radiation belt (~1 MeV) and ring current (~100 keV) electrons, it is shown that at some MLTs the bounce-averaged diffusion coefficients become rather insensitive to the details of the magnetic field configuration, while at other MLTs storm conditions can expand the range of equatorial pitch angles where gyro-resonant diffusion occurs and significantly enhance the diffusion rates. When MLT average is performed at drift shell L = 4.25 (a good approximation to drift average), the diffusion coefficients become quite independent of the magnetic field configuration for relativistic electrons, while the opposite is true for lower energy electrons. These results suggest that, at least for the March 17 2013 storm and for L ? 4.25, the commonly adopted dipole approximation of the Earth's magnetic field can be safely used for radiation belt electrons, while a realistic modeling of the magnetic field configuration is necessary to describe adequately the diffusion rates of ring current electrons.

  10. Energetic electron precipitation associated with pulsating aurora: EISCAT and Van Allen Probe observations

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

    Miyoshi, Y.; Oyama, S.; Saito, S.; Kurita, S.; Fujiwara, H.; Kataoka, R.; Ebihara, Y.; Kletzing, C.; Reeves, G.; Santolik, O.; et al

    2015-04-21

    Pulsating auroras show quasi-periodic intensity modulations caused by the precipitation of energetic electrons of the order of tens of keV. It is expected theoretically that not only these electrons but also subrelativistic/relativistic electrons precipitate simultaneously into the ionosphere owing to whistler mode wave-particle interactions. The height-resolved electron density profile was observed with the European Incoherent Scatter (EISCAT) Tromsø VHF radar on 17 November 2012. Electron density enhancements were clearly identified at altitudes >68 km in association with the pulsating aurora, suggesting precipitation of electrons with a broadband energy range from ~10 keV up to at least 200 keV. The riometermore » and network of subionospheric radio wave observations also showed the energetic electron precipitations during this period. During this period, the footprint of the Van Allen Probe-A satellite was very close to Tromsø and the satellite observed rising tone emissions of the lower band chorus (LBC) waves near the equatorial plane. Considering the observed LBC waves and electrons, we conducted a computer simulation of the wave-particle interactions. This showed simultaneous precipitation of electrons at both tens of keV and a few hundred keV, which is consistent with the energy spectrum estimated by the inversion method using the EISCAT observations. This result revealed that electrons with a wide energy range simultaneously precipitate into the ionosphere in association with the pulsating aurora, providing the evidence that pulsating auroras are caused by whistler chorus waves. We suggest that scattering by propagating whistler simultaneously causes both the precipitations of subrelativistic electrons and the pulsating aurora.« less

  11. Linearity of Climate Response to Increases in Black Carbon Aerosols

    SciTech Connect (OSTI)

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

    2013-04-19

    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 $ W^{-1} m^{2}$ when the semi-direct effects are accounted for and 0.22 K $ 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 $\\%$ $W^{-1}m^{2}$ . 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 $ 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.

  12. Bounce- and MLT-averaged diffusion coefficients in a physics-based magnetic field geometry obtained from RAM-SCB for the March 17 2013 storm

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

    Zhao, Lei; Yu, Yiqun; Delzanno, Gian Luca; Jordanova, Vania K.

    2015-04-01

    Local acceleration via whistler wave and particle interaction plays a significant role in particle dynamics in the radiation belt. In this work we explore gyro-resonant wave-particle interaction and quasi-linear diffusion in different magnetic field configurations related to the March 17 2013 storm. We consider the Earth's magnetic dipole field as a reference and compare the results against non-dipole field configurations corresponding to quiet and stormy conditions. The latter are obtained with the ring current-atmosphere interactions model with a self-consistent magnetic field RAM-SCB, a code that models the Earth's ring current and provides a realistic modeling of the Earth's magnetic field.more » By applying quasi-linear theory, the bounce- and MLT-averaged electron pitch angle, mixed term, and energy diffusion coefficients are calculated for each magnetic field configuration. For radiation belt (~1 MeV) and ring current (~100 keV) electrons, it is shown that at some MLTs the bounce-averaged diffusion coefficients become rather insensitive to the details of the magnetic field configuration, while at other MLTs storm conditions can expand the range of equatorial pitch angles where gyro-resonant diffusion occurs and significantly enhance the diffusion rates. When MLT average is performed at drift shell L = 4.25 (a good approximation to drift average), the diffusion coefficients become quite independent of the magnetic field configuration for relativistic electrons, while the opposite is true for lower energy electrons. These results suggest that, at least for the March 17 2013 storm and for L ≲ 4.25, the commonly adopted dipole approximation of the Earth's magnetic field can be safely used for radiation belt electrons, while a realistic modeling of the magnetic field configuration is necessary to describe adequately the diffusion rates of ring current electrons.« less

  13. AN OUTFLOW PERPENDICULAR TO THE RADIO JET IN THE SEYFERT NUCLEUS OF NGC5929

    SciTech Connect (OSTI)

    Riffel, Rogemar A.; Storchi-Bergmann, Thaisa; Riffel, Rogrio E-mail: thaisa@ufrgs.br

    2014-01-10

    We report the observation of an outflow perpendicular to the radio jet in near-infrared integral field spectra of the inner 250pc of the Seyfert2 galaxy NGC5929. The observations were obtained with the Gemini Near-infrared Integral Field Spectrograph at a spatial resolution of ?20pc and spectral resolution of R ? 5300 and reveal a region ?50pc wide crossing the nucleus and extending by ?300pc perpendicularly to the known radio jet in this galaxy. Along this structurewhich we call the south-east-north-west (SE-NW) stripthe emission line profiles show two velocity components, one blueshifted and the other redshifted by 150km s{sup 1} and 150km s{sup 1}, respectively, relative to the systemic velocity. We interpret these two components as being due to an outflow perpendicular to the radio jet, which is supported by low-frequency radio emission observed along the same region. We attribute this feature to the interaction of ambient gas with an ''equatorial outflow'' predicted in recent accretion disk and torus wind models. Perpendicularly to the SE-NW strip, thus approximately along the radio jet, single-component profiles show blueshifts of ? 150km s{sup 1} to the north-east and similar redshifts to the south-west, which can be attributed to gas counter-rotating relative to the stellar kinematics. More double-peaked profiles are observed in association with the two radio hot spots, attributed to interaction of the radio jet with the surrounding gas.

  14. Radiation-Hydrodynamic Simulations of Massive Star Formation with Protostellar Outflows

    SciTech Connect (OSTI)

    Cunningham, A J; Klein, R I; Krumholz, M R; McKee, C F

    2011-03-02

    We report the results of a series of AMR radiation-hydrodynamic simulations of the collapse of massive star forming clouds using the ORION code. These simulations are the first to include the feedback effects protostellar outflows, as well as protostellar radiative heating and radiation pressure exerted on the infalling, dusty gas. We find that that outflows evacuate polar cavities of reduced optical depth through the ambient core. These enhance the radiative flux in the poleward direction so that it is 1.7 to 15 times larger than that in the midplane. As a result the radiative heating and outward radiation force exerted on the protostellar disk and infalling cloud gas in the equatorial direction are greatly diminished. The simultaneously reduces the Eddington radiation pressure barrier to high-mass star formation and increases the minimum threshold surface density for radiative heating to suppress fragmentation compared to models that do not include outflows. The strength of both these effects depends on the initial core surface density. Lower surface density cores have longer free-fall times and thus massive stars formed within them undergo more Kelvin contraction as the core collapses, leading to more powerful outflows. Furthermore, in lower surface density clouds the ratio of the time required for the outflow to break out of the core to the core free-fall time is smaller, so that these clouds are consequently influenced by outflows at earlier stages of collapse. As a result, outflow effects are strongest in low surface density cores and weakest in high surface density one. We also find that radiation focusing in the direction of outflow cavities is sufficient to prevent the formation of radiation pressure-supported circumstellar gas bubbles, in contrast to models which neglect protostellar outflow feedback.

  15. University of Washington`s radioecological studies in the Marshall Islands, 1946-1977

    SciTech Connect (OSTI)

    Donaldson, L.R.; Seymour, A.H.; Nevissi, A.E.

    1997-07-01

    Since 1946, personnel from the School of Fisheries, University of Washington, have studied the effects of nuclear detonations and the ensuing radioactivity on the marine and terrestrial environments throughout the Central Pacific. A collection of reports and publications about these activities plus a collection of several thousand samples from these periods are kept at the School of Fisheries. General findings from the surveys show that (1) fission products were prevalent in organisms of the terrestrial environment whereas activation products were prevalent in marine organisms; (2) the best biological indicators of fallout radionuclides by environments were (a) terrestrial-coconuts, land crabs; (b) reef-algae, invertebrates; and (c) marine-plankton, fish. Studies of plutonium and americium in Bikini Atoll showed that during 1971-1977 the highest concentrations of {sup 241}Am, 2.85 Bq g-{close_quote} (77 pCi g{sup -1}) and {sup 239,240}Pu, 4.44 Bq g{sup -1} (120 pCi g{sup -1}), in surface sediments were found in the northwest part of the lagoon. The concentrations in the bomb craters were substantially lower than these values. Concentrations of soluble and particulate plutonium and americium in surface and deep water samples showed distributions similar to the sediment samples. That is, the highest concentration of these radionuclides in the water column were at locations with highest sediment concentration. Continuous circulation of water in the lagoon and exchange of water with open ocean resulted in removal of 111 G Bq y{sup -1} (3 Ci y{sup -1}) {sup 241}Am and 222 G Bq y{sup -1} (6 Ci y{sup -1}) {sup 239,240}Pu into the North Equatorial Current. A summary of the surveys, findings, and the historical role of the Laboratory in radioecological studies of the Marshall Islands are presented. 23 refs., 1 fig., 1 tab.

  16. Effects of turbulence on cosmic ray propagation in protostars and young star/disk systems

    SciTech Connect (OSTI)

    Fatuzzo, Marco; Adams, Fred C. E-mail: fca@umich.edu

    2014-05-20

    The magnetic fields associated with young stellar objects are expected to have an hour-glass geometry, i.e., the magnetic field lines are pinched as they thread the equatorial plane surrounding the forming star but merge smoothly onto a background field at large distances. With this field configuration, incoming cosmic rays experience both a funneling effect that acts to enhance the flux impinging on the circumstellar disk and a magnetic mirroring effect that acts to reduce that flux. To leading order, these effects nearly cancel out for simple underlying magnetic field structures. However, the environments surrounding young stellar objects are expected to be highly turbulent. This paper shows how the presence of magnetic field fluctuations affects the process of magnetic mirroring, and thereby changes the flux of cosmic rays striking circumstellar disks. Turbulence has two principle effects: (1) the (single) location of the magnetic mirror point found in the absence of turbulence is replaced with a wide distribution of values. (2) The median of the mirror point distribution moves outward for sufficiently large fluctuation amplitudes (roughly when ?B/B {sub 0} > 0.2 at the location of the turbulence-free mirror point); the distribution becomes significantly non-Gaussian in this regime as well. These results may have significant consequences for the ionization fraction of the disk, which in turn dictates the efficiency with which disk material can accrete onto the central object. A similar reduction in cosmic ray flux can occur during the earlier protostellar stages; the decrease in ionization can help alleviate the magnetic braking problem that inhibits disk formation.

  17. Energetic electron precipitation associated with pulsating aurora: EISCAT and Van Allen Probe observations

    SciTech Connect (OSTI)

    Miyoshi, Y.; Oyama, S.; Saito, S.; Kurita, S.; Fujiwara, H.; Kataoka, R.; Ebihara, Y.; Kletzing, C.; Reeves, G.; Santolik, O.; Clilverd, M.; Rodger, C. J.; Turunen, E.; Tsuchiya, F.

    2015-04-21

    Pulsating auroras show quasi-periodic intensity modulations caused by the precipitation of energetic electrons of the order of tens of keV. It is expected theoretically that not only these electrons but also subrelativistic/relativistic electrons precipitate simultaneously into the ionosphere owing to whistler mode wave-particle interactions. The height-resolved electron density profile was observed with the European Incoherent Scatter (EISCAT) Troms VHF radar on 17 November 2012. Electron density enhancements were clearly identified at altitudes >68 km in association with the pulsating aurora, suggesting precipitation of electrons with a broadband energy range from ~10 keV up to at least 200 keV. The riometer and network of subionospheric radio wave observations also showed the energetic electron precipitations during this period. During this period, the footprint of the Van Allen Probe-A satellite was very close to Troms and the satellite observed rising tone emissions of the lower band chorus (LBC) waves near the equatorial plane. Considering the observed LBC waves and electrons, we conducted a computer simulation of the wave-particle interactions. This showed simultaneous precipitation of electrons at both tens of keV and a few hundred keV, which is consistent with the energy spectrum estimated by the inversion method using the EISCAT observations. This result revealed that electrons with a wide energy range simultaneously precipitate into the ionosphere in association with the pulsating aurora, providing the evidence that pulsating auroras are caused by whistler chorus waves. We suggest that scattering by propagating whistler simultaneously causes both the precipitations of subrelativistic electrons and the pulsating aurora.

  18. Anti-addiction drug ibogaine inhibits voltage-gated ionic currents: A study to assess the drug's cardiac ion channel profile

    SciTech Connect (OSTI)

    Koenig, Xaver; Kovar, Michael; Rubi, Lena; Mike, Agnes K.; Lukacs, Peter; Gawali, Vaibhavkumar S.; Todt, Hannes; Hilber, Karlheinz; Sandtner, Walter

    2013-12-01

    The plant alkaloid ibogaine has promising anti-addictive properties. Albeit not licenced as a therapeutic drug, and despite hints that ibogaine may perturb the heart rhythm, this alkaloid is used to treat drug addicts. We have recently reported that ibogaine inhibits human ERG (hERG) potassium channels at concentrations similar to the drugs affinity for several of its known brain targets. Thereby the drug may disturb the heart's electrophysiology. Here, to assess the drug's cardiac ion channel profile in more detail, we studied the effects of ibogaine and its congener 18-Methoxycoronaridine (18-MC) on various cardiac voltage-gated ion channels. We confirmed that heterologously expressed hERG currents are reduced by ibogaine in low micromolar concentrations. Moreover, at higher concentrations, the drug also reduced human Na{sub v}1.5 sodium and Ca{sub v}1.2 calcium currents. Ion currents were as well reduced by 18-MC, yet with diminished potency. Unexpectedly, although blocking hERG channels, ibogaine did not prolong the action potential (AP) in guinea pig cardiomyocytes at low micromolar concentrations. Higher concentrations (? 10 ?M) even shortened the AP. These findings can be explained by the drug's calcium channel inhibition, which counteracts the AP-prolonging effect generated by hERG blockade. Implementation of ibogaine's inhibitory effects on human ion channels in a computer model of a ventricular cardiomyocyte, on the other hand, suggested that ibogaine does prolong the AP in the human heart. We conclude that therapeutic concentrations of ibogaine have the propensity to prolong the QT interval of the electrocardiogram in humans. In some cases this may lead to cardiac arrhythmias. - Highlights: We study effects of anti-addiction drug ibogaine on ionic currents in cardiomyocytes. We assess the cardiac ion channel profile of ibogaine. Ibogaine inhibits hERG potassium, sodium and calcium channels. Ibogaines effects on ion channels are a potential source of cardiac arrhythmias. 18-Methoxycoronaridine has a lower affinity for cardiac ion channels than ibogaine.

  19. Parameterization and analysis of 3-D radiative transfer in clouds

    SciTech Connect (OSTI)

    Varnai, Tamas

    2012-03-16

    This report provides a summary of major accomplishments from the project. The project examines the impact of radiative interactions between neighboring atmospheric columns, for example clouds scattering extra sunlight toward nearby clear areas. While most current cloud models donâ??t consider these interactions and instead treat sunlight in each atmospheric column separately, the resulting uncertainties have remained unknown. This project has provided the first estimates on the way average solar heating is affected by interactions between nearby columns. These estimates have been obtained by combining several years of cloud observations at three DOE Atmospheric Radiation Measurement (ARM) Climate Research Facility sites (in Alaska, Oklahoma, and Papua New Guinea) with simulations of solar radiation around the observed clouds. The importance of radiative interactions between atmospheric columns was evaluated by contrasting simulations that included the interactions with those that did not. This study provides lower-bound estimates for radiative interactions: It cannot consider interactions in cross-wind direction, because it uses two-dimensional vertical cross-sections through clouds that were observed by instruments looking straight up as clouds drifted aloft. Data from new DOE scanning radars will allow future radiative studies to consider the full three-dimensional nature of radiative processes. The results reveal that two-dimensional radiative interactions increase overall day-and-night average solar heating by about 0.3, 1.2, and 4.1 Watts per meter square at the three sites, respectively. This increase grows further if one considers that most large-domain cloud simulations have resolutions that cannot specify small-scale cloud variability. For example, the increases in solar heating mentioned above roughly double for a fairly typical model resolution of 1 km. The study also examined the factors that shape radiative interactions between atmospheric columns and found that local effects were often much larger than the overall values mentioned above, and were especially large for high sun and near convective clouds such as cumulus. The study also found that statistical methods such as neural networks appear promising for enabling cloud models to consider radiative interactions between nearby atmospheric columns. Finally, through collaboration with German scientists, the project found that new methods (especially one called â??stepwise krigingâ?) show great promise in filling gaps between cloud radar scans. If applied to data from the new DOE scanning cloud radars, these methods can yield large, continuous three-dimensional cloud structures for future radiative simulations.

  20. Radiative Heating of the ISCCP Upper Level Cloud Regimes and its Impact on the Large-scale Tropical Circulation

    SciTech Connect (OSTI)

    Li, Wei; Schumacher, Courtney; McFarlane, Sally A.

    2013-01-31

    Radiative heating profiles of the International Satellite Cloud Climatology Project (ISCCP) cloud regimes (or weather states) were estimated by matching ISCCP observations with radiative properties derived from cloud radar and lidar measurements from the Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) sites at Manus, Papua New Guinea, and Darwin, Australia. Focus was placed on the ISCCP cloud regimes containing the majority of upper level clouds in the tropics, i.e., mesoscale convective systems (MCSs), deep cumulonimbus with cirrus, mixed shallow and deep convection, and thin cirrus. At upper levels, these regimes have average maximum cloud occurrences ranging from 30% to 55% near 12 km with variations depending on the location and cloud regime. The resulting radiative heating profiles have maxima of approximately 1 K/day near 12 km, with equal heating contributions from the longwave and shortwave components. Upper level minima occur near 15 km, with the MCS regime showing the strongest cooling of 0.2 K/day and the thin cirrus showing no cooling. The gradient of upper level heating ranges from 0.2 to 0.4 K/(day?km), with the most convectively active regimes (i.e., MCSs and deep cumulonimbus with cirrus) having the largest gradient. When the above heating profiles were applied to the 25-year ISCCP data set, the tropics-wide average profile has a radiative heating maximum of 0.45Kday-1 near 250 hPa. Column-integrated radiative heating of upper level cloud accounts for about 20% of the latent heating estimated by the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR). The ISCCP radiative heating of tropical upper level cloud only slightly modifies the response of an idealized primitive equation model forced with the tropics-wide TRMM PR latent heating, which suggests that the impact of upper level cloud is more important to large-scale tropical circulation variations because of convective feedbacks rather than direct forcing by the cloud radiative heating profiles. However, the height of the radiative heating maxima and gradient of the heating profiles are important to determine the sign and patterns of the horizontal circulation anomaly driven by radiative heating at upper levels.

  1. [Ni(H{sub 2}O){sub 4}]{sub 3}[U(OH,H{sub 2}O)(UO{sub 2}){sub 8}O{sub 12}(OH){sub 3}], crystal structure and comparison with uranium minerals with U{sub 3}O{sub 8}-type sheets

    SciTech Connect (OSTI)

    Rivenet, Murielle; Vigier, Nicolas; Roussel, Pascal; Abraham, Francis

    2009-04-15

    The new U(VI) compound, [Ni(H{sub 2}O){sub 4}]{sub 3}[U(OH,H{sub 2}O)(UO{sub 2}){sub 8}O{sub 12}(OH){sub 3}], was synthesized by mild hydrothermal reaction of uranyl and nickel nitrates. The crystal-structure was solved in the P-1 space group, a=8.627(2), b=10.566(2), c=12.091(4) A and alpha=110.59(1), beta=102.96(2), gamma=105.50(1){sup o}, R=0.0539 and wR=0.0464 from 3441 unique observed reflections and 151 parameters. The structure of the title compound is built from sheets of uranium polyhedra closely related to that in beta-U{sub 3}O{sub 8}. Within the sheets [(UO{sub 2})(OH)O{sub 4}] pentagonal bipyramids share equatorial edges to form chains, which are cross-linked by [(UO{sub 2})O{sub 4}] and [UO{sub 4}(H{sub 2}O)(OH)] square bipyramids and through hydroxyl groups shared between [(UO{sub 2})(OH)O{sub 4}] pentagonal bipyramids. The sheets are pillared by sharing the apical oxygen atoms of the [(UO{sub 2})(OH)O{sub 4}] pentagonal bipyramids with the oxygen atoms of [NiO{sub 2}(H{sub 2}O){sub 4}] octahedral units. That builds a three-dimensional framework with water molecules pointing towards the channels. On heating [Ni(H{sub 2}O){sub 4}]{sub 3}[U(OH,H{sub 2}O)(UO{sub 2}){sub 8}O{sub 12}(OH){sub 3}] decomposes into NiU{sub 3}O{sub 10}. - Graphical abstract: The framework of [Ni(H{sub 2}O){sub 4}]{sub 3}[U(OH,H{sub 2}O)(UO{sub 2}){sub 8}O{sub 12}(OH){sub 3}] built from uranium polyhedra sheets pillared by Ni-centered octahedra.

  2. Evolution of flux ropes in the magnetotail: A three-dimensional global hybrid simulation

    SciTech Connect (OSTI)

    Lu, S.; Lin, Y.; Wang, X. Y.; Lu, Q. M. Huang, C.; Wu, M. Y.; Wang, S.; Wang, R. S.

    2015-05-15

    Flux ropes in the Earth's magnetotail are widely believed to play a crucial role in energy transport during substorms and the generation of energetic particles. Previous kinetic simulations are limited to the local-scale regime, and thus cannot be used to study the structure associated with the geomagnetic field and the global-scale evolution of the flux ropes. Here, the evolution of flux ropes in the magnetotail under a steady southward interplanetary magnetic field are studied with a newly developed three-dimensional global hybrid simulation model for dynamics ranging from the ion Larmor radius to the global convection time scales. Magnetic reconnection with multiple X-lines is found to take place in the near-tail current sheet at geocentric solar magnetospheric distances x=?30R{sub E}??15R{sub E} around the equatorial plane (z=0). The magnetotail reconnection layer is turbulent, with a nonuniform structure and unsteady evolution, and exhibits properties of typical collisionless fast reconnection with the Hall effect. A number of small-scale flux ropes are generated through the multiple X-line reconnection. The diameter of the flux ropes is several R{sub E}, and the spatial scale of the flux ropes in the dawn-dusk direction is on the order of several R{sub E} and does not extend across the entire section of the magnetotail, contrary to previous models and MHD simulation results and showing the importance of the three-dimensional effects. The nonuniform and unsteady multiple X-line reconnection with particle kinetic effects leads to various kinds of flux rope evolution: The small-scale flux ropes propagate earthward or tailward after formation, and eventually merge into the near-Earth region or the mid-/distant-tail plasmoid, respectively. During the propagation, some of the flux ropes can be tilted in the geocentric solar magnetospheric (x,y) plane with respect to the y (dawn-dusk) axis. Coalescence between flux ropes is also observed. At the same time, the evolution of the flux ropes in the multiple X-line reconnection layer can also lead to the acceleration and heating of ions.

  3. Effect of the L499M mutation of the ascomycetous Botrytis aclada laccase on redox potential and catalytic properties

    SciTech Connect (OSTI)

    Osipov, Evgeny [A. N. Bach Institute of Biochemistry, Leninsky Prospect 33/2, Moscow 119071 (Russian Federation); Polyakov, Konstantin [A. N. Bach Institute of Biochemistry, Leninsky Prospect 33/2, Moscow 119071 (Russian Federation); Engelhardt Institute of Molecular Biology, Vavilova Str. 32, Moscow 119991 (Russian Federation); Kittl, Roman [BOKU University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Wien (Austria); Shleev, Sergey [RSC Kurchatov Institute, Acad. Kurchatov Sq. 1, Moscow 123182 (Russian Federation); Malm University, 205 06 Malm (Sweden); Dorovatovsky, Pavel [RSC Kurchatov Institute, Acad. Kurchatov Sq. 1, Moscow 123182 (Russian Federation); Tikhonova, Tamara, E-mail: ttikhonova@inbi.ras.ru [A. N. Bach Institute of Biochemistry, Leninsky Prospect 33/2, Moscow 119071 (Russian Federation); Hann, Stephan; Ludwig, Roland [BOKU University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Wien (Austria); Popov, Vladimir [A. N. Bach Institute of Biochemistry, Leninsky Prospect 33/2, Moscow 119071 (Russian Federation); RSC Kurchatov Institute, Acad. Kurchatov Sq. 1, Moscow 123182 (Russian Federation)

    2014-11-01

    The structures of the ascomycetous B. aclada laccase and its L499M T1-site mutant have been solved at 1.7 resolution. The mutant enzyme shows a 140 mV lower redox potential of the type 1 copper and altered kinetic behaviour. The wild type and the mutant have very similar structures, which makes it possible to relate the changes in the redox potential to the L499M mutation Laccases are members of a large family of multicopper oxidases that catalyze the oxidation of a wide range of organic and inorganic substrates accompanied by the reduction of dioxygen to water. These enzymes contain four Cu atoms per molecule organized into three sites: T1, T2 and T3. In all laccases, the T1 copper ion is coordinated by two histidines and one cysteine in the equatorial plane and is covered by the side chains of hydrophobic residues in the axial positions. The redox potential of the T1 copper ion influences the enzymatic reaction and is determined by the nature of the axial ligands and the structure of the second coordination sphere. In this work, the laccase from the ascomycete Botrytis aclada was studied, which contains conserved Ile491 and nonconserved Leu499 residues in the axial positions. The three-dimensional structures of the wild-type enzyme and the L499M mutant were determined by X-ray crystallography at 1.7 resolution. Crystals suitable for X-ray analysis could only be grown after deglycosylation. Both structures did not contain the T2 copper ion. The catalytic properties of the enzyme were characterized and the redox potentials of both enzyme forms were determined: E{sub 0} = 720 and 580 mV for the wild-type enzyme and the mutant, respectively. Since the structures of the wild-type and mutant forms are very similar, the change in the redox potential can be related to the L499M mutation in the T1 site of the enzyme.

  4. Development of the scintillator-based probe for fast-ion losses in the HL-2A tokamak

    SciTech Connect (OSTI)

    Zhang, Y. P. Liu, Yi; Yuan, G. L.; Song, X. Y.; Yang, J. W.; Li, X.; Chen, W.; Li, Y.; Yan, L. W.; Song, X. M.; Yang, Q. W.; Duan, X. R.; Luo, X. B.; Liu, Y. Q.; Hua, Y.; Isobe, M.

    2014-05-15

    A new scintillator-based lost fast-ion probe (SLIP) has been developed and operated in the HL-2A tokamak [L. W. Yan, X. R. Duan, X. T. Ding, J. Q. Dong, Q. W. Yang, Yi Liu, X. L. Zou, D. Q. Liu, W. M. Xuan, L. Y. Chen, J. Rao, X. M. Song, Y. Huang, W. C. Mao, Q. M. Wang, Q. Li, Z. Cao, B. Li, J. Y. Cao, G. J. Lei, J. H. Zhang, X. D. Li, W. Chen, J. Chen, C. H. Cui, Z. Y. Cui, Z. C. Deng, Y. B. Dong, B. B. Feng, Q. D. Gao, X. Y. Han, W. Y. Hong, M. Huang, X. Q. Ji, Z. H. Kang, D. F. Kong, T. Lan, G. S. Li, H. J. Li, Qing Li, W. Li, Y. G. Li, A. D. Liu, Z. T. Liu, C. W. Luo, X. H. Mao, Y. D. Pan, J. F. Peng, Z. B. Shi, S. D. Song, X. Y. Song, H. J. Sun, A. K. Wang, M. X. Wang, Y. Q. Wang, W. W. Xiao, Y. F. Xie, L. H. Yao, D. L. Yu, B. S. Yuan, K. J. Zhao, G. W. Zhong, J. Zhou, J. C. Yan, C. X. Yu, C. H. Pan, Y. Liu, and the HL-2A Team , Nucl. Fusion 51, 094016 (2011)] to measure the losses of neutral beam ions. The design of the probe is based on the concept of the ?-particle detectors on Tokamak Fusion Test Reactor (TFTR) using scintillator plates. The probe is capable of traveling across an equatorial plane port and sweeping the aperture angle rotationally with respect to the axis of the probe shaft by two step motors, in order to optimize the radial position and the collimator angle. The energy and the pitch angle of the lost fast ions can be simultaneously measured if the two-dimensional image of scintillation light intensity due to the impact of the lost fast ions is detected. Measurements of the fast-ion losses using the probe have been performed during HL-2A neutral beam injection discharges. The clear experimental evidence of enhanced losses of beam ions during disruptions has been obtained by means of the SLIP system. A detailed description of the probe system and the first experimental results are reported.

  5. Physical Mechanisms for the Maintenance of GCM-Simulated Madden-Julian Oscillation over the Indian Ocean and Pacific

    SciTech Connect (OSTI)

    Deng, Liping; Wu, Xiaoqing

    2011-05-05

    The kinetic energy budget is conducted to analyze the physical processes responsible for the improved Madden-Julian Oscillation (MJO) simulated by the Iowa State University general circulation models (ISUGCM). The modified deep convection scheme that includes the revised convection closure, convection trigger condition and convective momentum transport (CMT) enhances the equatorial (10oS-10oN) MJO-related perturbation kinetic energy (PKE) in the upper troposphere and leads to more robust and coherent eastward propagating MJO signal. In the MJO source region-the Indian Ocean (45oE-120oE), the upper-tropospheric MJO PKE is maintained by the vertical convergence of wave energy flux and the barotropic conversion through the horizontal shear of mean flow. In the convectively active region-the western Pacific (120oE-180o), the upper-tropospheric MJO PKE is supported by the convergence of horizontal and vertical wave energy fluxes. Over the central-eastern Pacific (180o-120oW), where convection is suppressed, the upper-tropospheric MJO PKE is mainly due to the horizontal convergence of wave energy flux. The deep convection trigger condition produces stronger convective heating which enhances the perturbation available potential energy (PAPE) production and the upward wave energy fluxes, and leads to the increased MJO PKE over the Indian Ocean and western Pacific. The trigger condition also enhances the MJO PKE over the central-eastern Pacific through the increased convergence of meridional wave energy flux from the subtropical latitudes of both hemispheres. The revised convection closure affects the response of mean zonal wind shear to the convective heating over the Indian Ocean and leads to the enhanced upper-tropospheric MJO PKE through the barotropic conversion. The stronger eastward wave energy flux due to the increase of convective heating over the Indian Ocean and western Pacific by the revised closure is favorable to the eastward propagation of MJO and the convergence of horizontal wave energy flux over the central-eastern Pacific. The convection-induced momentum tendency tends to decelerate the upper-tropospheric wind which results in a negative work to the PKE budget in the upper troposphere. However, the convection momentum tendency accelerates the westerly wind below 800 hPa over the western Pacific, which is partially responsible for the improved MJO simulation.

  6. Sloan Digital Sky Survey II (SDSS-II), Data Release 7, including the Legacy Survey

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

    The Sloan Digital Sky Survey (SDSS) is a series of three interlocking imaging and spectroscopic surveys, carried out over an eight-year period with a dedicated 2.5m telescope located at Apache Point Observatory in Southern New Mexico. The seventh data release (DR7) from the SDSS represents a completion of the overall, original project, though SDSS-III began in 2008 and will build upon the knowledge gained already. The SDSS Legacy Survey provided a uniform, well-calibrated map of more than 7,500 square degrees of the North Galactic Cap, and three stripes in the South Galactic Cap totaling 740 square degrees. The central stripe in the South Galactic Gap, Stripe 82, was scanned multiple times to enable a deep co-addition of the data and to enable discovery of variable objects. Legacy data supported studies ranging from asteroids and nearby stars to the large-scale structure of the universe. All of the imaging data have been processed to yield calibrated astrometric and photometric parameters and classifications. These parameters are available in one or more tables in a database accessible via the Catalog Archive Server (CAS) at http://cas.sdss.org/astro. [taken and edited from the Legacy page at http://www.sdss.org/legacy/index.html] All three surveys summarized are: 1) Legacy: an imaging survey in five bands over a contiguous 7646 deg2 high-latitude elliptical region in the Northern Galactic Cap, plus an additional 750 deg2 in the Southern Galactic Cap, together with spectroscopy of complete samples of galaxies and quasars covering about 8200 square degrees. The total imaging area in the Legacy survey is 8423 square degrees; 2) SEGUE: (Sloan Extension for Galactic Understanding and Exploration): additional imaging of 3240 deg2 of sky at lower Galactic latitudes, together with spectroscopy of 240,000 stars towards 200 sight lines covering 1400 square degrees (spread throughout the Legacy and SEGUE imaging footprints), to study the structure of the Milky Way; 3) Supernova: the equivalent of about 80 repeated imaging scans of the Southern Equatorial Stripe (ra > 310 or ra < 59; -1.25 > dec < 1.25) obtained in variable weather conditions (some clouds) to search for supernovae in the redshift range 0.1 < z < 0.4. The catalog derived from the images includes more than 350 million celestial objects, and spectra of 930,000 galaxies, 120,000 quasars, and 460,000 stars. The data are fully calibrated and reduced, carefully checked for quality, and publicly accessible through efficient databases. The data have been publicly released in a series of annual data releases, culminating in the final data release, DR7.

  7. Sediment studies at Bikini Atoll part 3. Inventories of some long-lived gamma-emitting radionuclides associated with lagoon surface sediments

    SciTech Connect (OSTI)

    Noshkin, V.E.

    1997-12-01

    Surface sediment samples were collected during 1979 from 87 locations in the lagoon at Bikini Atoll. The collections were made to better define the concentrations and distribution of long-lived radionuclides associated with the bottom material and to show what modifications occurred to the composition of the surface sediment from the nuclear testing program conducted by the United States at the Atoll between 1946 and 1958. This is the last of three reports on Bikini sediment studies. In this report, we discuss the concentrations and inventories of the residual long-lived gamma-emitting radionuclides in sediments from the lagoon. The gamma-emitting radionuclides detected most frequently in sediments collected in 1979, in addition to Americium-241 ({sup 241}Am) (discussed in the second report of this series), included Cesium-137 ({sup 137}Cs), Bismuth-207 ({sup 207}Bi), Europium-155 ({sup 155}Eu), and Cobalt-60 ({sup 60}Co). Other man-made, gamma-emitting radionuclides such as Europium-152,154 ({sup 152,154}Eu), Antimony-125 ({sup 125}Sb), and Rhodium-101,102m ({sup 101,102m}Rh) were occasionally measured above detection limits in sediments near test site locations. The mean inventories for {sup 137}Cs, {sup 207}Ei, {sup 155}Eu, and {sup 60}Co in the surface 4 cm of the lagoon sediment to be 1.7, 0.56, 7.76, and 0.74 TBq, respectively. By June 1997, radioactive decay would reduce these values to 1.1, 0.38, 0.62, and 0.07 TBq, respectively. Some additional loss results from a combination of different processes that continuously mobilize and return some amount of the radionuclides to the water column. The water and dissolved constituents are removed from the lagoon through channels and exchange with the surface waters of the north equatorial Pacific Ocean. Highest levels of these radionuclides are found in surface deposits lagoonward of the Bravo Crater. Lowest concentrations and inventories are associated with sediment lagoonward of the eastern reef. The quantities in the 0-4 cm surface layer are estimated to be less than 35% of the total inventory to depth in the sediment column.

  8. SUZAKU VIEW OF THE SWIFT/BAT ACTIVE GALACTIC NUCLEI. V. TORUS STRUCTURE OF TWO LUMINOUS RADIO-LOUD ACTIVE GALACTIC NUCLEI (3C 206 AND PKS 0707-35)

    SciTech Connect (OSTI)

    Tazaki, Fumie; Ueda, Yoshihiro; Terashima, Yuichi; Mushotzky, Richard F.; Tombesi, Francesco

    2013-07-20

    We present the results from broadband X-ray spectral analysis of 3C 206 and PKS 0707-35 with Suzaku and Swift/BAT, two of the most luminous unobscured and obscured radio-loud active galactic nuclei (AGNs) with hard X-ray luminosities of 10{sup 45.5} erg s{sup -1} and 10{sup 44.9} erg s{sup -1} (14-195 keV), respectively. Based on the radio core luminosity, we estimate that the X-ray spectrum of 3C 206 contains a significant ({approx}60% in the 14-195 keV band) contribution from the jet, while it is negligible in PKS 0707-35. We can successfully model the spectra with the jet component (for 3C 206), the transmitted emission, and two reflection components from the torus and the accretion disk. The reflection strengths from the torus are found to be R{sub torus}({identical_to} {Omega}/2{pi}) = 0.29 {+-} 0.18 and 0.41 {+-} 0.18 for 3C 206 and PKS 0707-35, respectively, which are smaller than those in typical Seyfert galaxies. Utilizing the torus model by Ikeda et al., we quantify the relation between the half-opening angle of a torus ({theta}{sub oa}) and the equivalent width of an iron-K line. The observed equivalent width of 3C 206, < 71 eV, constrains the column density in the equatorial plane to N{sub H}{sup eq} <10{sup 23} cm{sup -2}, or the half-opening angle to {theta}{sub oa} > 80 Degree-Sign if N{sub H}{sup eq} =10{sup 24} cm{sup -2} is assumed. That of PKS 0707-35, 72 {+-} 36 eV, is consistent with N{sub H}{sup eq} {approx}10{sup 23} cm{sup -2}. Our results suggest that the tori in luminous radio-loud AGNs are only poorly developed. The trend is similar to that seen in radio-quiet AGNs, implying that the torus structure is not different between AGNs with jets and without jets.

  9. Oceanic Trace Gases Numeric Data Packages from the Carbon Dioxide Information Analysis Center (CDIAC)

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

    CDIAC products include numeric data packages, publications, trend data, atlases, models, etc. and can be searched for by subject area, keywords, authors, product numbers, time periods, collection sites, spatial references, etc. Most data sets or packages, many with numerous data files, are free to download from CDIAC's ftp area. CDIAC lists the following numeric data packages under the broad heading of Oceanic Trace Gases: Carbon Dioxide, Hydrographic, and Chemical Data Obtained during the R/V Ronald H. Brown Repeat Hydrography Cruise in the Atlantic Ocean: CLIVAR CO2 Section A16S_2005 ( 01/11/05 - 022405) • Determination of Carbon Dioxide, Hydrographic, and Chemical Parameters during the R/V Nathaniel B. Palmer Cruise in the Southern Indian Ocean (WOCE Section S04I, 050396 - 070496) • Inorganic Carbon, Nutrient, and Oxygen Data from the R/V Ronald H. Brown Repeat Hydrography Cruise in the Atlantic Ocean: CLIVAR CO2 Section A16N_2003a (060403 – 081103) • Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Maurice Ewing Cruise in the Atlantic Ocean (WOCE Section A17, 010494 - 032194) • Global Ocean Data Analysis Project GLODAP: Results and Data • Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Knorr Cruises in the North Atlantic Ocean on WOCE Sections AR24 (1102 – 120596) and A24, A20, and A22 (053097 – 090397) • Carbon Dioxide, Hydrographic and Chemical Data Obtained During the Nine R/V Knorr Cruises Comprising the Indian Ocean CO2 Survey (WOCE Sections I8SI9S, I9N, I8NI5E, I3, I5WI4, I7N, I1, I10, and I2; 120 194 – 012296) • Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Meteor Cruise 28/1 in the South Atlantic Ocean (WOCE Section A8, 032994 - 051294) • Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Knorr Cruise 138-3, -4, and -5 in the South Pacific Ocean (WOCE Sections P6E, P6C, and P6W, 050292 - 073092) • Global Distribution of Total Inorganic Carbon and Total Alkalinity below the deepest winter mixed layer depths • Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V John V. Vickers Cruise in the Pacific Ocean (WOCE Section P13, NOAA CGC92 Cruise, 080492 – 102192) • Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Hesperides Cruise in the Atlantic Ocean (WOCE Section A5, 071492 - 081592) • Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Thomas G. Thompson Cruise in the Pacific Ocean (WOCE Section P10, 100593 – 111093) • The International Intercomparison Exercise of Underway fCO2 Systems during the R/V Meteor Cruise 36/1 in the North Atlantic Ocean • Carbon Dioxide, Hydrographic, and Chemical Data Obtained during the R/V Meteor Cruise 22/5 in the South Atlantic Ocean (WOCE Section A10, Dec. 1992-Jan, 1993) • Carbon Dioxide, Hydrographic, and Chemical Data Obtained in the South Pacific Ocean (WOCE Sections P16A/P17A, P17E/P19S, and P19C, R/V Knorr , Oct. 1992-April 1993) • Surface Water and Atmospheric Underway Carbon Data Obtained During the World Ocean Circulation Experiment Indian Ocean Survey Cruises (R/V Knorr, Dec. 1994 – Jan, 1996) • Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Akademik Ioffe Cruise in the South Pacific Ocean (WOCE Section S4P, Feb.-April 1992) • Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Thomas Washington Cruise TUNES-1 in the Equatorial Pacific Ocean (WOCE section P17C) • Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Thomas Washington Cruise TUNES-3 in the Equatorial Pacific Ocean (WOCE section P16C) • Carbon-14 Measurements in Surface Water CO2 from the Atlantic, Indian and Pacific Oceans, 1965-1994 • Carbon Dioxide, Hydrographic, and Chemical Data Obtained During R/V Meteor Cruise 18/1 in the North Atlantic Ocean (WOCE Section A1E) • Carbon Dioxide, Hydrographic, and Chemical Data Obtained in the Central South Pacific Ocean (WOCE Sections P17S and P16S) during the TUNES-2 Expedition of the R/V Thomas Washington, July-August, 1991 • Total Carbon Dioxide, Hydrographic, and Nitrate Measurements in the Southwest Pacific during Austral Autumn, 1990: Results from NOAA/PMEL CGC-90 Cruise • Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Meteor Cruise 15/3 in the South Atlantic Ocean (WOCE Section A9, February March 1991) • Carbon Dioxide Concentrations in Surface Water and the Atmosphere During 1986-1989 NOAA/PMEL Cruises in the Pacific and Indian Oceans • Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Meteor Cruise 11/5 in the South Atlantic and Northern Weddell Sea Areas (WOCE sections A-12 and A-21) • Surface Water and Atmospheric Carbon Dioxide and Nitrous Oxide Observations by Shipboard Automated Gas Chromatography: Results from Expeditions Between 1977 and 1990 • Indian Ocean Radiocarbon: Data from the INDIGO 1, 2, and 3 Cruises • Carbonate Chemistry of the North Pacific Ocean • Carbonate Chemistry of the Weddell Sea • GEOSECS Atlantic, Pacific, Indian, and Mediterranean Radiocarbon Data •\tTransient Tracers in the Oceans (TTO) - Hydrographic Data and Carbon Dioxide Systems with Revised Carbon Chemistry Data.

  10. Oceanic Trace Gases Numeric Data Packages from the Carbon Dioxide Information Analysis Center (CDIAC)

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

    CDIAC products include numeric data packages, publications, trend data, atlases, models, etc. and can be searched for by subject area, keywords, authors, product numbers, time periods, collection sites, spatial references, etc. Most data sets or packages, many with numerous data files, are free to download from CDIAC's ftp area. CDIAC lists the following numeric data packages under the broad heading of Oceanic Trace Gases: Carbon Dioxide, Hydrographic, and Chemical Data Obtained during the R/V Ronald H. Brown Repeat Hydrography Cruise in the Atlantic Ocean: CLIVAR CO2 Section A16S_2005 ( 01/11/05 - 022405) Determination of Carbon Dioxide, Hydrographic, and Chemical Parameters during the R/V Nathaniel B. Palmer Cruise in the Southern Indian Ocean (WOCE Section S04I, 050396 - 070496) Inorganic Carbon, Nutrient, and Oxygen Data from the R/V Ronald H. Brown Repeat Hydrography Cruise in the Atlantic Ocean: CLIVAR CO2 Section A16N_2003a (060403 081103) Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Maurice Ewing Cruise in the Atlantic Ocean (WOCE Section A17, 010494 - 032194) Global Ocean Data Analysis Project GLODAP: Results and Data Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Knorr Cruises in the North Atlantic Ocean on WOCE Sections AR24 (1102 120596) and A24, A20, and A22 (053097 090397) Carbon Dioxide, Hydrographic and Chemical Data Obtained During the Nine R/V Knorr Cruises Comprising the Indian Ocean CO2 Survey (WOCE Sections I8SI9S, I9N, I8NI5E, I3, I5WI4, I7N, I1, I10, and I2; 120 194 012296) Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Meteor Cruise 28/1 in the South Atlantic Ocean (WOCE Section A8, 032994 - 051294) Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Knorr Cruise 138-3, -4, and -5 in the South Pacific Ocean (WOCE Sections P6E, P6C, and P6W, 050292 - 073092) Global Distribution of Total Inorganic Carbon and Total Alkalinity below the deepest winter mixed layer depths Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V John V. Vickers Cruise in the Pacific Ocean (WOCE Section P13, NOAA CGC92 Cruise, 080492 102192) Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Hesperides Cruise in the Atlantic Ocean (WOCE Section A5, 071492 - 081592) Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Thomas G. Thompson Cruise in the Pacific Ocean (WOCE Section P10, 100593 111093) The International Intercomparison Exercise of Underway fCO2 Systems during the R/V Meteor Cruise 36/1 in the North Atlantic Ocean Carbon Dioxide, Hydrographic, and Chemical Data Obtained during the R/V Meteor Cruise 22/5 in the South Atlantic Ocean (WOCE Section A10, Dec. 1992-Jan, 1993) Carbon Dioxide, Hydrographic, and Chemical Data Obtained in the South Pacific Ocean (WOCE Sections P16A/P17A, P17E/P19S, and P19C, R/V Knorr , Oct. 1992-April 1993) Surface Water and Atmospheric Underway Carbon Data Obtained During the World Ocean Circulation Experiment Indian Ocean Survey Cruises (R/V Knorr, Dec. 1994 Jan, 1996) Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Akademik Ioffe Cruise in the South Pacific Ocean (WOCE Section S4P, Feb.-April 1992) Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Thomas Washington Cruise TUNES-1 in the Equatorial Pacific Ocean (WOCE section P17C) Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Thomas Washington Cruise TUNES-3 in the Equatorial Pacific Ocean (WOCE section P16C) Carbon-14 Measurements in Surface Water CO2 from the Atlantic, Indian and Pacific Oceans, 1965-1994 Carbon Dioxide, Hydrographic, and Chemical Data Obtained During R/V Meteor Cruise 18/1 in the North Atlantic Ocean (WOCE Section A1E) Carbon Dioxide, Hydrographic, and Chemical Data Obtained in the Central South Pacific Ocean (WOCE Sections P17S and P16S) during the TUNES-2 Expedition of the R/V Th

  11. Final Technical Report for NSF/DOE partnership grant 1004284/ER54905/SC0004660; 2011- 2013

    SciTech Connect (OSTI)

    Stenzel, Reiner; Urrutia, Manuel

    2014-10-15

    Research has been performed on two topics: (1) Nonlinear time-dependent phenomena in the regime of electron magnetohydrodynamics (EMHD). (2) Plasma structures forming ”bubbles”. The latter are regions of localized density depletions or enhancements separated from the ambient plasma by sheaths or double layers. Three-dimensional magnetic null points can also be considered as ”magnetic bubbles”. Nonlinear EMHD fields are generated by pulsed magnetic loops. The magnetic field varies in time faster than an ion cyclotron period, hence interacts only with electrons. Space charge electric fields are created when magnetic forces try to separate electrons from ions. Electric and magnetic forces nearly balance to keep the plasma quasi neutral. This leads to rotational electron motions, i.e. Hall currents and associated magnetic perturbations. When the time scale falls between the ion and electron cyclotron period the magnetic perturbation is convected in the whistler mode. When the time-varying magnetic field exceeds the background magnetic field the whistler mode becomes highly nonlinear since its properties depend on the total magnetic field. When the time-varying magnetic field creates magnetic null points or null lines EMHD breaks down. Electrons can be accelerated in null lines which dissipated magnetic energy like in magnetic reconnection. Energized electrons with anisotropic distributions create secondary whistler instabilities. These effects have been observed in field topologies resembling spheromaks and field-reversed configurations (FRCs). The whistler mode propagation near magnetic nulls is not trivial when the field gradients and wavelength are comparable. Ray tracing is inappropriate when the WKB approximation breaks down. Experiments have been started to map wave propagation on curved field lines with null points. Initial results show that whistlers in highly nonuniform fields have highly oblique phase velocities but the energy flow remains dominantly along the field. Density bubbles are created by anode discharges, typically forming spherical ”fireballs” bounded by a double layer. In a magnetized plasma the shape becomes cylindrical, in nonuniform magnetic fields many asymmetric fireball shapes are possible. Due to electron energization the fireball plasma has higher density and temperature than the ambient plasma. The double layer can also be produced by a high transparency positively biased grid. Instabilities arise from the electron transit through the plasma bubble and the double layer. When a permanent magnet is biased positively the electrons perform ExB drifts in the equatorial plane between the poles. Electron drift modes are excited with a high spectral contents. Similarly, a negatively biased magnet produces a disk-shaped plasma bubble. The cold magnet emits secondary electrons due to the impact of energetic ions. Such magnetron discharges exhibit a variety of instabilities which affect the cross-field transport and sputtering applications. This report will summarize the main effects observed and provide references to more detailed publications.

  12. Laser- and Radar-based Mission Concepts for Suborbital and Spaceborne Monitoring of Seismic Surface Waves

    SciTech Connect (OSTI)

    Foxall, W; Schultz, C A; Tralli, D M

    2004-09-21

    The development of a suborbital or spaceborne system to monitor seismic waves poses an intriguing prospect for advancing the state of seismology. This capability would enable an unprecedented global mapping of the velocity structure of the earth's crust, understanding of earthquake rupture dynamics and wave propagation effects, and event source location, characterization and discrimination that are critical for both fundamental earthquake research and nuclear non-proliferation applications. As part of an ongoing collaboration between LLNL and JPL, an advanced mission concept study assessed architectural considerations and operational and data delivery requirements, extending two prior studies by each organization--a radar-based satellite system (JPL) for earthquake hazard assessment and a feasibility study of space- or UAV-based laser seismometer systems (LLNL) for seismic event monitoring. Seismic wave measurement requirements include lower bounds on detectability of specific seismic sources of interest and wave amplitude accuracy for different levels of analysis, such as source characterization, discrimination and tomography, with a 100 {micro}m wave amplitude resolution for waves nominally traveling 5 km/s, an upper frequency bound based on explosion and earthquake surface displacement spectra, and minimum horizontal resolution (1-5 km) and areal coverage, in general and for targeted observations. For a radar system, corresponding engineering and operational factors include: Radar frequency (dictated by required wave amplitude measurement accuracy and maximizing ranging, Doppler or interferometric sensitivity), time sampling (maximum seismic wave frequency and velocity), and overall system considerations such as mass, power and data rate. Technical challenges include characterization of, and compensation for, phase distortion resulting from atmospheric and ionospheric perturbations and turbulence, and effects of ground scattering characteristics and seismic ground motion on phase coherence over interferometric time intervals. Since the temporal sampling requirement may be finer than that possible for a high-altitude sensor to traverse a synthetic aperture length, a geostationary, real-aperture Ka-band system or constellation for equatorial and moderate-latitude global coverage is one option considered. The short wavelength would maximize interferometric sensitivity to small surface displacements and minimize required antenna area. Engineering issues include the design and deployment of a large ({approx} 100m) fixed aperture antenna; and fast electronic beam steering (entire aperture within nominal 1 s interferometric interval) with high-efficiency integrated transmit/receive modules. For a suborbital system, platform instability is an issue whereas at high earth orbit signal-to-noise and attendant power requirements dominate. Data delivery requirements include large-volume data storage and transmission; development of real-time, on-board event detection and processing algorithms, and data management structures for these very large data sets. A far-term roadmap would comprise a proof-of-concept demonstration using a laser or radar system mounted on a stratospheric balloon or UAV to image seismic wavefields from planned events (e.g. large mine blasts and/or purpose-designed explosions) and earthquake targets of opportunity. The technological challenges to developing any such seismic monitoring system, whether laser- or radar-based, are at this stage enormous. However, these concept studies suggest the long-term feasibility of such a system and drive the development of enabling technologies while fostering collaboration on meeting scientific and operational challenges of agencies such as NASA, DOE and DoD.

  13. PHYSICAL PROPERTIES OF MAIN-BELT COMET 176P/LINEAR

    SciTech Connect (OSTI)

    Hsieh, Henry H.; Ishiguro, Masateru; Lacerda, Pedro; Jewitt, David E-mail: p.lacerda@qub.ac.uk E-mail: jewitt@ucla.edu

    2011-07-15

    We present a physical characterization of comet 176P/LINEAR, the third discovered member of the new class of main-belt comets, which exhibit cometary activity but are dynamically indistinguishable from main-belt asteroids. Observations show the object exhibiting a fan-shaped tail for at least one month in late 2005, but then becoming inactive in early 2006. During this active period, we measure broadband colors of B - V = 0.63 {+-} 0.02, V - R = 0.35 {+-} 0.02, and R - I = 0.31 {+-} 0.04. Using data from when the object was observed to be inactive, we derive best-fit IAU phase function parameters of H = 15.10 {+-} 0.05 mag and G = 0.15 {+-} 0.10, and best-fit linear phase function parameters of m(1, 1, 0) = 15.35 {+-} 0.05 mag and {beta} = 0.038 {+-} 0.005 mag deg{sup -1}. From this baseline phase function, we find that 176P exhibits a mean photometric excess of {approx}30% during its active period, implying an approximate total coma dust mass of M{sub d} {approx} (7.2 {+-} 3.6) x 10{sup 4} kg. From inactive data obtained in early 2007, we find a rotation period of P{sub rot} = 22.23 {+-} 0.01 hr and a peak-to-trough photometric range of {Delta}m {approx} 0.7 mag. Phasing our photometric data from 176P's 2005 active period to this rotation period, we find that the nucleus exhibits a significantly smaller photometric range than in 2007 that cannot be accounted for by coma damping effects, and as such, are attributed by us to viewing geometry effects. A detailed analysis of these geometric effects showed that 176P is likely to be a highly elongated object with an axis ratio of 1.8 < b/a < 2.1, an orbital obliquity of {epsilon} {approx} 60{sup 0}, and a solstice position at a true anomaly of {nu}{sub o} = 20{sup 0} {+-} 20{sup 0}. Numerical modeling of 176P's dust emission found that its activity can only be reproduced by asymmetric dust emission, such as a cometary jet. We find plausible fits to our observations using models assuming {approx}10 {mu}m dust particles continuously emitted over the period during which 176P was observed to be active, and a jet direction of 180{sup 0} {approx}< {alpha}{sub jet} {approx}< 120{sup 0} and {delta}{sub jet} {approx} -60{sup 0}. We do not find good fits to our observations using models of impulsive dust emission, i.e., what would be expected if 176P's activity was an ejecta cloud resulting from an impact into non-volatile asteroid regolith. Since for a rotating body, the time-averaged direction of a non-equatorial jet is equivalent to the direction of the nearest rotation pole, we find an equivalent orbital obliquity of 50{sup 0} {approx}< {epsilon} {approx}< 75{sup 0}, consistent with the results of our light curve analysis. Furthermore, the results of both our light curve analysis and dust modeling analysis are consistent with the seasonal heating hypothesis used to explain the modulation of 176P's activity. Additional observations are highly encouraged to further characterize 176P's active behavior as the object approaches perihelion on 2011 July 1.

  14. Health, safety, and environmental risks from energy production: A year-long reality check

    SciTech Connect (OSTI)

    Oldenburg, C.M.

    2011-04-01

    Large-scale carbon dioxide capture and storage (CCS) offers the benefit of reducing CO{sub 2} emissions and thereby mitigating climate change risk, but it will also bring its own health, safety, and environmental risks. Curtis M. Oldenburg, Editor-in-Chief, considers these risks in the context of the broader picture of energy production. Over the last year, there have been major acute health, safety, and environmental (HSE) consequences related to accidents involving energy production from every major primary energy source. These are, in chronological order: (i) the Upper Big Branch (coal) Mine disaster, (ii) the Gulf of Mexico Macondo (oil) well blowout, (iii) the San Bruno (natural gas) pipeline leak and explosion, and (iv) the Fukushima (nuclear) reactor radioactivity releases. Briefly, the Upper Big Branch Mine disaster occurred in West Virginia on April 5, 2010, when natural methane in the mine ignited, causing the deaths of 29 miners, the worst coal mine disaster in the USA since 1970. Fifteen days later, the Macondo oil well in the Gulf of Mexico suffered a blowout, with a gas explosion and fire on the floating drilling platform that killed 11 people. The oil and gas continued to flow out of the well at the seafloor until July 15, 2010, spilling a total of approximately 5 million barrels of oil into the sea. On September 9, 2010, a 30-inch (76-cm) buried, steel, natural gas pipeline in San Bruno, California, leaked gas and exploded in a residential neighborhood, killing 8 people in their homes and burning a total of 38 homes. Flames were up to 1000 ft (300 m) high, and the initial explosion itself reportedly measured 1.1 on the Richter scale. Finally, on March 11, 2011, a magnitude 9.0 earthquake off the coast of Japan's main island, Honshu, caused a tsunami that crippled the backup power and associated cooling systems for six reactor cores and their spent fuel storage tanks at the Fukushima nuclear power plant. At time of writing, workers trying to bring the crisis under control have been exposed to dangerous levels of radiation, and radioactive water and particulates have been released to the sea and atmosphere. These four disasters, all of which occurred within the past 12 months, were not unprecedented; similar events differing only in detail have happened around the world before, and such events will occur again. Today, developed nations primarily use fossil fuels to create affordable energy for comforts such as lighting, heating and air-conditioning, refrigeration, transportation, education, and entertainment, as well as for powering manufacturing, which creates jobs and a wealth of material goods. In addition to the risks of the existing energy infrastructure that have become obvious through these recent disasters, there is also the ongoing risk of climate change that comes from the vast emissions of greenhouse gases, primarily CO{sub 2}, from the burning of fossil fuels. The implementation of CO{sub 2} capture and storage (CCS) will help mitigate CO{sub 2} emissions from fossil fuel energy, but it also carries with it HSE risks. In my personal interactions with the public and with students, the main concern voiced is whether CO{sub 2} could leak out of the deep reservoirs into which it is injected and rise up out of the ground, smothering people and animals at the ground surface. Another concern expressed is that CO{sub 2} pipelines could fail and cause similar gaseous plumes of CO{sub 2}. The widespread concerns about CO{sub 2} leaking out over the ground surface may be inspired by events that have happened within natural systems in equatorial Africa, in Indonesia, and in Italy. Researchers have been investigating a wide variety of HSE risks of geologic CO{sub 2} storage for some time and have determined that wells are the main potential pathways for significant leakage from the deep subsurface. I discuss the acute HSE risks of CO{sub 2} leakage through wells and from pipelines, and compare the behavior of failures in CO{sub 2} wells and pipelines with oil and gas analogues from which most of our experien