Sample records for tar sands including

  1. Treating tar sands formations with karsted zones

    DOEpatents

    Vinegar, Harold J.; Karanikas, John Michael

    2010-03-09

    Methods for treating a tar sands formation are described herein. The tar sands formation may have one or more karsted zones. Methods may include providing heat from one or more heaters to one or more karsted zones of the tar sands formation to mobilize fluids in the formation. At least some of the mobilized fluids may be produced from the formation.

  2. Treating tar sands formations with dolomite

    DOEpatents

    Vinegar, Harold J.; Karanikas, John Michael

    2010-06-08

    Methods for treating a tar sands formation are described herein. The tar sands formation may include dolomite and hydrocarbons. Methods may include providing heat at less than the decomposition temperature of dolomite from one or more heaters to at least a portion of the formation. At least some of the hydrocarbon fluids are mobilized in the formation. At least some of the hydrocarbon fluids may be produced from the formation.

  3. Method for filtering solvent and tar sand mixtures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kelterborn, J. C.; Stone, R. A.

    1985-09-03

    A method for filtering spent tar sands from a bitumen and organic solvent solution comprises separating the solution into two streams wherein the bulk of the coarser spent tar sand is in a first stream and has an average particle size of about 10 to about 100 mesh and the bulk of the finer spent tar sand is in a second stream; producing a filter cake by filtering the coarser spent tar sand from the first stream; and filtering the finer spent tar sand from the second stream with the filter cake. The method is particularly useful for filtering solutionsmore » of bitumen extracted from bitumen containing diatomite, spent diatomite and organic solvent.« less

  4. Creating fluid injectivity in tar sands formations

    DOEpatents

    Stegemeier, George Leo; Beer, Gary Lee; Zhang, Etuan

    2012-06-05

    Methods for treating a tar sands formation are described herein. Methods for treating a tar sands may include heating a portion of a hydrocarbon layer in the formation from one or more heaters located in the portion. The heat may be controlled to increase the permeability of at least part of the portion to create an injection zone in the portion with an average permeability sufficient to allow injection of a fluid through the injection zone. A drive fluid and/or an oxidizing fluid may be provided into the injection zone. At least some hydrocarbons including mobilized hydrocarbons are produced from the portion.

  5. Creating fluid injectivity in tar sands formations

    DOEpatents

    Stegemeier, George Leo; Beer, Gary Lee; Zhang, Etuan

    2010-06-08

    Methods for treating a tar sands formation are described herein. Methods for treating a tar sands may include heating a portion of a hydrocarbon layer in the formation from one or more heaters located in the portion. The heat may be controlled to increase the permeability of at least part of the portion to create an injection zone in the portion with an average permeability sufficient to allow injection of a fluid through the injection zone. A drive fluid and/or an oxidizing fluid may be provided into the injection zone. At least some hydrocarbons are produced from the portion.

  6. Method and apparatus for hydrocarbon recovery from tar sands

    DOEpatents

    Westhoff, J.D.; Harak, A.E.

    1988-05-04

    A method and apparatus for utilizing tar sands having a broad range of bitumen content is disclosed. More particularly, tar sands are pyrolyzed in a cyclone retort with high temperature gases recycled from the cyclone retort to produce oil and hydrocarbon products. The spent tar sands are then burned at 2000/degree/F in a burner to remove residual char and produce a solid waste that is easily disposable. The process and apparatus have the advantages of being able to utilize tar sands having a broad range of bitumen content and the advantage of producing product gases that are free from combustion gases and thereby have a higher heating value. Another important advantage is rapid pyrolysis of the tar sands in the cyclone so as to effectively utilize smaller sized reactor vessels for reducing capitol and operating costs. 1 fig., 1 tab.

  7. Method and apparatus for hydrocarbon recovery from tar sands

    DOEpatents

    Westhoff, James D.; Harak, Arnold E.

    1989-01-01

    A method and apparatus for utilizing tar sands having a broad range of bitumen content is disclosed. More particularly, tar sands are pyrolyzed in a cyclone retort with high temperature gases recycled from the cyclone retort to produce oil and hydrocarbon products. The spent tar sands are then burned at 2000.degree. F. in a burner to remove residual char and produce a solid waste that is easily disposable. The process and apparatus have the advantages of being able to utilize tar sands having a broad range of bitumen content and the advantage of producing product gases that are free from combustion gases and thereby have a higher heating value. Another important advantage is rapid pyrolysis of the tar sands in the cyclone so as to effectively utilize smaller sized reactor vessels for reducing capitol and operating costs.

  8. Creating and maintaining a gas cap in tar sands formations

    DOEpatents

    Vinegar, Harold J.; Karanikas, John Michael; Dinkoruk, Deniz Sumnu; Wellington, Scott Lee

    2010-03-16

    Methods for treating a tar sands formation are disclosed herein. Methods for treating a tar sands formation may include providing heat to at least part of a hydrocarbon layer in the formation from one or more heaters located in the formation. Pressure may be allowed to increase in an upper portion of the formation to provide a gas cap in the upper portion. At least some hydrocarbons are produced from a lower portion of the formation.

  9. The potential use of tar sand bitumen as paving asphalt

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Petersen, J.C.

    1988-01-01

    In this paper several research reports describing the preparation of potential paving asphalts from tar sand bitumen are reviewed and the results of the studies compared. The tar sand asphalts described in the studies were prepared from 1) hot water-recovered bitumen from deposits near San Luis Obispo, California (Edna deposits), and deposits near Vernal and Sunnyside, Utah; and 2) bitumen recovered from the Northwest Asphalt Ridge deposits near Vernal, Utah, by both in situ steamflood and in situ combustion recovery processes. Important properties of the tar sand asphalts compare favorably with those of specification petroleum asphalts. Laboratory data suggest thatmore » some tar sand asphalts may have superior aging characteristics and produce more water-resistant paving mixtures than typical petroleum asphalts.« less

  10. Supercritical-Fluid Extraction of Oil From Tar Sands

    NASA Technical Reports Server (NTRS)

    Compton, L. E.

    1982-01-01

    New supercritical solvent mixtures have been laboratory-tested for extraction of oil from tar sands. Mixture is circulated through sand at high pressure and at a temperature above critical point, dissolving organic matter into the compressed gas. Extract is recovered from sand residues. Low-temperature super-critical solvents reduce energy consumption and waste-disposal problems.

  11. In situ heat treatment of a tar sands formation after drive process treatment

    DOEpatents

    Vinegar, Harold J.; Stanecki, John

    2010-09-21

    A method for treating a tar sands formation includes providing a drive fluid to a hydrocarbon containing layer of the tar sands formation to mobilize at least some hydrocarbons in the layer. At least some first hydrocarbons from the layer are produced. Heat is provided to the layer from one or more heaters located in the formation. At least some second hydrocarbons are produced from the layer of the formation. The second hydrocarbons include at least some hydrocarbons that are upgraded compared to the first hydrocarbons produced by using the drive fluid.

  12. Aviation Turbine Fuels from Tar Sands Bitumen and Heavy Oils. Part 1. Process Analysis.

    DTIC Science & Technology

    1984-09-01

    Uinta Basin .......................too.... 11 b . Asphalt Ridge ........................ 13 c.* Tar Sand Triangle ..... to .. .. . .. .. . 15 e...Estimated ............**..* 7 3 CHARACTERISTICS OF UTAH’S MAJOR TAR SANDS ....... 12 4 UINTA BASIN DEPOSITS ................... *........ 13 *.5 UINTA ...7 UINTA BASIN , UTAH PROPERTIES -SUNNYSIDE ........ 20 8 UINTA BASIN , UTAH PROPERTIES -P. R. SPRINGS . 22 r9 ESTIMATED CALIFORNIA TAR SAND DISTRIBUTION

  13. Method of producing drive fluid in situ in tar sands formations

    DOEpatents

    Mudunuri, Ramesh Raju; Jaiswal, Namit; Vinegar, Harold J.; Karanikas, John Michael

    2010-03-23

    Methods of treating a tar sands formation are described herein. Methods for treating a tar sands may include providing heat to at least part of a hydrocarbon layer in the formation from one or more heaters located in the formation. The heat may be allowed to transfer from the heaters to at least a portion of the formation such that a drive fluid is produced in situ in the formation. The drive fluid may move at least some mobilized, visbroken, and/or pyrolyzed hydrocarbons from a first portion of the formation to a second portion of the formation. At least some of the mobilized, visbroken, and/or pyrolyzed hydrocarbons may be produced from the formation.

  14. Controlling and assessing pressure conditions during treatment of tar sands formations

    DOEpatents

    Zhang, Etuan; Beer, Gary Lee

    2015-11-10

    A method for treating a tar sands formation includes providing heat to at least part of a hydrocarbon layer in the tar sands formation from a plurality of heaters located in the formation. Heat is allowed to transfer from the heaters to at least a portion of the formation. A pressure in the portion of the formation is controlled such that the pressure remains below a fracture pressure of the formation overburden while allowing the portion of the formation to heat to a selected average temperature of at least about 280.degree. C. and at most about 300.degree. C. The pressure in the portion of the formation is reduced to a selected pressure after the portion of the formation reaches the selected average temperature.

  15. Heating tar sands formations to visbreaking temperatures

    DOEpatents

    Karanikas, John Michael [Houston, TX; Colmenares, Tulio Rafael [Houston, TX; Zhang, Etuan [Houston, TX; Marino, Marian [Houston, TX; Roes, Augustinus Wilhelmus Maria [Houston, TX; Ryan, Robert Charles [Houston, TX; Beer, Gary Lee [Houston, TX; Dombrowski, Robert James [Houston, TX; Jaiswal, Namit [Houston, TX

    2009-12-22

    Methods for treating a tar sands formation are described herein. Methods may include heating at least a section of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. The heat may be controlled so that at least a majority of the section reaches an average temperature of between 200.degree. C. and 240.degree. C., which results in visbreaking of at least some hydrocarbons in the section. At least some visbroken hydrocarbon fluids may be produced from the formation.

  16. Class I cultural resource overview for oil shale and tar sands areas in Colorado, Utah and Wyoming.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    O'Rourke, D.; Kullen, D.; Gierek, L.

    2007-11-01

    In August 2005, the U.S. Congress enacted the Energy Policy Act of 2005, Public Law 109-58. In Section 369 of this Act, also known as the 'Oil Shale, Tar Sands, and Other Strategic Unconventional Fuels Act of 2005', Congress declared that oil shale and tar sands (and other unconventional fuels) are strategically important domestic energy resources that should be developed to reduce the nation's growing dependence on oil from politically and economically unstable foreign sources. The Bureau of Land Management (BLM) is developing a Programmatic Environmental Impact Statement (PEIS) to evaluate alternatives for establishing commercial oil shale and tar sandsmore » leasing programs in Colorado, Wyoming, and Utah. This PEIS evaluates the potential impacts of alternatives identifying BLM-administered lands as available for application for commercial leasing of oil shale resources within the three states and of tar sands resources within Utah. The scope of the analysis of the PEIS also includes an assessment of the potential effects of future commercial leasing. This Class I cultural resources study is in support of the Draft Oil Shale and Tar Sands Resource Management Plan Amendments to Address Land Use Allocations in Colorado, Utah, and Wyoming and Programmatic Environmental Impact Statement and is an attempt to synthesize archaeological data covering the most geologically prospective lands for oil shale and tar sands in Colorado, Utah, and Wyoming. This report is based solely on geographic information system (GIS) data held by the Colorado, Utah, and Wyoming State Historic Preservation Offices (SHPOs). The GIS data include the information that the BLM has provided to the SHPOs. The primary purpose of the Class I cultural resources overview is to provide information on the affected environment for the PEIS. Furthermore, this report provides recommendations to support planning decisions and the management of cultural resources that could be impacted by future oil shale

  17. Heating tar sands formations while controlling pressure

    DOEpatents

    Stegemeier, George Leo [Houston, TX; Beer, Gary Lee [Houston, TX; Zhang, Etuan [Houston, TX

    2010-01-12

    Methods for treating a tar sands formation are described herein. Methods may include heating at least a section of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. A pressure in the majority of the section may be maintained below a fracture pressure of the formation. The pressure in the majority of the section may be reduced to a selected pressure after the average temperature reaches a temperature that is above 240.degree. C. and is at or below pyrolysis temperatures of hydrocarbons in the section. At least some hydrocarbon fluids may be produced from the formation.

  18. The search for a source rock for the giant Tar Sand triangle accumulation, southeastern Utah

    USGS Publications Warehouse

    Huntoon, J.E.; Hansley, P.L.; Naeser, N.D.

    1999-01-01

    for the White Rim oil. The most attractive potential sources for White Rim oil include beds within one or more of the following formations: the Proterozoic Chuar Group, which is present in the subsurface southwest of the Tar Sand triangle; the Mississippian Delle Phosphatic Member of the Deseret Limestone and equivalent formations, the Permian Kaibab Limestone, the Sinbad Limestone Member of the Triassic Moenkopi Formation, and the Jurassic Arapien Shale, Twin Creek Limestone, and Carmel Formation, which are present west of the Tar Sand triangle; the Pennsylvanian Paradox Formation in the Paradox basin east of the Tar Sand triangle; and the Permian Park City Formation northwest of the Tar Sand triangle. Each formation has a high total organic carbon content and is distributed over a wide enough geographic area to have provided a huge volume of oil. Source beds in all of the formations reached thermal maturity at times prior to or during the time that migration into the White Rim is interpreted to have occurred. Based on all available data, the most likely source for the Tar Sand triangle appears to be the Mississippian Delle Phosphatic Member of the Deseret Limestone. Secondary migration out of the Delle is interpreted to have occurred during the Cretaceous, during Sevier thrusting. Subsequent tertiary migration into the Tar Sand triangle reservoir is interpreted to have occurred later, during middle Tertiary Laramide deformation.

  19. Aspects of tar sands development in Nigeria

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Adewusi, V.A.

    1992-07-01

    Development of Nigerian massive reserves of crude bitumen and associated heavy oil is imminent in view of the impacts that the huge importation of these materials and their products have on the nation's economy, coupled with the depleting reserves of Nigeria and highlights the appropriate production technology options and their environmental implications. The utilization potentials of these resources are also enumerated, as well as the government's role in achieving accelerated, long-term tar sands development in the country.

  20. Aviation Turbine Fuels from Tar Sands Bitumen and Heavy Oils. Part 2. Laboratory Sample Production.

    DTIC Science & Technology

    1987-07-01

    tar sand bitumen from West Central Kentucky; and Sunnyside tar sand bitumen from the Uinta Basin , Utah. Each of the feedstocks had unique...fuel and about 50 volume percent heavy gas oil (600-1000°F). The Westken bitumen was overall the heaviest of the four feedstocks evaluated. K factors...was 40 weight percent and about 20 weight percent in the total crude. 3. San Ardo Heavy oil The San Ardo field is located in the Coastal basin of the

  1. Production from multiple zones of a tar sands formation

    DOEpatents

    Karanikas, John Michael; Vinegar, Harold J

    2013-02-26

    A method for treating a tar sands formation includes providing heat to at least part of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. The heat is allowed to transfer from the heaters to at least a portion of the formation. Fluids are produced from the formation through at least one production well that is located in at least two zones in the formation. The first zone has an initial permeability of at least 1 darcy. The second zone has an initial of at most 0.1 darcy. The two zones are separated by a substantially impermeable barrier.

  2. Systems and methods for producing hydrocarbons from tar sands formations

    DOEpatents

    Li, Ruijian [Katy, TX; Karanikas, John Michael [Houston, TX

    2009-07-21

    A system for treating a tar sands formation is disclosed. A plurality of heaters are located in the formation. The heaters include at least partially horizontal heating sections at least partially in a hydrocarbon layer of the formation. The heating sections are at least partially arranged in a pattern in the hydrocarbon layer. The heaters are configured to provide heat to the hydrocarbon layer. The provided heat creates a plurality of drainage paths for mobilized fluids. At least two of the drainage paths converge. A production well is located to collect and produce mobilized fluids from at least one of the converged drainage paths in the hydrocarbon layer.

  3. In situ heat treatment from multiple layers of a tar sands formation

    DOEpatents

    Vinegar, Harold J.

    2010-11-30

    A method for treating a tar sands formation is disclosed. The method includes providing a drive fluid to a first hydrocarbon containing layer of the formation to mobilize at least some hydrocarbons in the first layer. At least some of the mobilized hydrocarbons are allowed to flow into a second hydrocarbon containing layer of the formation. Heat is provided to the second layer from one or more heaters located in the second layer. At least some hydrocarbons are produced from the second layer of the formation.

  4. Laboratory studies to characterize the efficacy of sand capping a coal tar-contaminated sediment.

    PubMed

    Hyun, Seunghun; Jafvert, Chad T; Lee, Linda S; Rao, P Suresh C

    2006-06-01

    Placement of a microbial active sand cap on a coal tar-contaminated river sediment has been suggested as a cost effective remediation strategy. This approach assumes that the flux of contaminants from the sediment is sufficiently balanced by oxygen and nutrient fluxes into the sand layer such that microbial activity will reduce contaminant concentrations within the new benthic zone and reduce the contaminant flux to the water column. The dynamics of such a system were evaluated using batch and column studies with microbial communities from tar-contaminated sediment under different aeration and nutrient inputs. In a 30-d batch degradation study on aqueous extracts of coal tar sediment, oxygen and nutrient concentrations were found to be key parameters controlling the degradation rates of polycyclic aromatic hydrocarbons (PAHs). For the five PAHs monitored (naphthalene, fluorene, phenanthrene, anthracene, and pyrene), degradation rates were inversely proportional to molecular size. For the column studies, where three columns were packed with a 20-cm sand layer on the top of a 5 cm of sediment layer, flow was established to sand layers with (1) aerated water, (2) N(2) sparged water, or (3) HgCl(2)-sterilized N(2) sparged water. After steady-state conditions, PAH concentrations in effluents were the lowest in the aerated column, except for pyrene, whose concentration was invariant with all effluents. These laboratory scale studies support that if sufficient aeration can be achieved in the field through either active and passive means, the resulting microbially active sand layer can improve the water quality of the benthic zone and reduce the flux of many, but not all, PAHs to the water column.

  5. An NMR (Nuclear Magnetic Resonance) Investigation of the Chemical Association and Molecular Dynamics in Asphalt Ridge Tar Sand Ore and Bitumen

    DOE R&D Accomplishments Database

    Netzel, D. A.; Coover, P. T.

    1987-09-01

    Preliminary studies on tar sand bitumen given in this report have shown that the reassociation of tar sand bitumen to its original molecular configuration after thermal stressing is a first-order process requiring nearly a week to establish equilibrium. Studies were also conducted on the dissolution of tar sand bitumen in solvents of varying polarity. At a high-weight fraction of solute to solvent the apparent molecular weight of the bitumen molecules was greater than that of the original bitumen when dissolved in chloroform-d{sub 1} and benzene-d{sub 6}. This increase in the apparent molecular weight may be due to micellar formation or a weak solute-solvent molecular complex. Upon further dilution with any of the solvents studied, the apparent molecular weight of the tar sand bitumen decreased because of reduced van der Waals forces of interaction and/or hydrogen bonding. To define the exact nature of the interactions, it will be necessary to have viscosity measurements of the solutions.

  6. Method of condensing vaporized water in situ to treat tar sands formations

    DOEpatents

    Hsu, Chia-Fu

    2010-03-16

    Methods for treating a tar sands formation are described herein. Methods may include heating at least a section of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. Heat may be allowed to transfer from the heaters to at least a first portion of the formation. Conditions may be controlled in the formation so that water vaporized by the heaters in the first portion is selectively condensed in a second portion of the formation. At least some of the fluids may be produced from the formation.

  7. Potential impacts to perennial springs from tar sand mining, processing, and disposal on the Tavaputs Plateau, Utah, USA.

    PubMed

    Johnson, William P; Frederick, Logan E; Millington, Mallory R; Vala, David; Reese, Barbara K; Freedman, Dina R; Stenten, Christina J; Trauscht, Jacob S; Tingey, Christopher E; Kip Solomon, D; Fernandez, Diego P; Bowen, Gabriel J

    2015-11-01

    Similar to fracking, the development of tar sand mining in the U.S. has moved faster than understanding of potential water quality impacts. Potential water quality impacts of tar sand mining, processing, and disposal to springs in canyons incised approximately 200 m into the Tavaputs Plateau, at the Uinta Basin southern rim, Utah, USA, were evaluated by hydrogeochemical sampling to determine potential sources of recharge, and chemical thermodynamic estimations to determine potential changes in transfer of bitumen compounds to water. Because the ridgetops in an area of the Tavaputs Plateau named PR Spring are starting to be developed for their tar sand resource, there is concern for potential hydrologic connection between these ridgetops and perennial springs in adjacent canyons on which depend ranching families, livestock, wildlife and recreationalists. Samples were collected from perennial springs to examine possible progression with elevation of parameters such as temperature, specific conductance, pH, dissolved oxygen, isotopic tracers of phase change, water-rock interaction, and age since recharge. The groundwater age dates indicate that the springs are recharged locally. The progression of hydrogeochemical parameters with elevation, in combination with the relatively short groundwater residence times, indicate that the recharge zone for these springs includes the surrounding ridges, and thereby suggests a hydrologic connection between the mining, processing, disposal area and the springs. Estimations based on chemical thermodynamic approaches indicate that bitumen compounds will have greatly enhanced solubility in water that comes into contact with the residual bitumen-solvent mixture in disposed tailings relative to water that currently comes into contact with natural tar. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Ranking methodology for determining the relative favorability for commercial development of US tar-sand deposits

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aamodt, P.L.; Freiwald, J.G.

    1983-03-01

    As a part of the DOE's program to stimulate petroleum production from unconventional sources, the Los Alamos National Laboratory has developed a methodology to compare and rank tar sand deposits, based on their suitability for commercial development. Major categories influencing favorability were identified and evaluated to determine their individual and collective impacts. To facilitate their evaluation, deposit characteristics, extraction technologies, environmental controls, and institutional constraints were broken down into their elements. The elements were assessed singly and in interactive groups to determine their influence on favorability for commercial development. A numerical value was assigned each element to signify its estimatedmore » importance relative to the other elements. Eight tar sand deposits were evaluated using only one major category, deposit characteristics. This initial, and only partial favorability assessment, was solely a test of the methodology, and it was considered successful. Because only one of the four major categories was used for this initial favorability ranking, and also because the available deposit characteristic data were barely adequate for the test, these first results should be used only as an example of how the methodology is to be applied when more complete data are available. The eight deposits and their relative favorability rankings for commercial development, based only on the deposit characteristics, are Sunnyside, Utah; Asphalt Ridge, Utah; Edna, California; Santa Rosa, New Mexico; Tar Sand Triangle, Utah; PR Spring, Utah; Uvalde, Texas; and circle cliffs, Utah.« less

  9. Moving hydrocarbons through portions of tar sands formations with a fluid

    DOEpatents

    Stegemeier, George Leo; Mudunuri, Ramesh Raju; Vinegar, Harold J.; Karanikas, John Michael; Jaiswal, Namit; Mo, Weijian

    2010-05-18

    A method for treating a tar sands formation is disclosed. The method includes heating a first portion of a hydrocarbon layer in the formation from one or more heaters located in the first portion. The heat is controlled to increase a fluid injectivity of the first portion. A drive fluid and/or an oxidizing fluid is injected and/or created in the first portion to cause at least some hydrocarbons to move from a second portion of the hydrocarbon layer to a third portion of the hydrocarbon layer. The second portion is between the first portion and the third portion. The first, second, and third portions are horizontally displaced from each other. The third portion is heated from one or more heaters located in the third portion. Hydrocarbons are produced from the third portion of the formation. The hydrocarbons include at least some hydrocarbons from the second portion of the formation.

  10. Tar sand extraction by steam stimulation and steam drive: measurement of physical properties

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Linberg, W.R.

    The measurement of the following thermophysical properties of Utah tar sands is in progress: thermal conductivity, specific heat relative permeability, and viscosity (of the recovered bitumen). During the report period (October 1, 1978 to November 1, 1979), experimental procedures have been developed and a basic data set has been measured. Additionally, standard core analysis has been performed for four drill sites in the Asphalt Ridge, Utah area.

  11. The extraction of bitumen from western oil sands. Final report, July 1989--September 1993

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Oblad, A.G.; Bunger, J.W.; Dahlstrom, D.A.

    1994-03-01

    Research and development of surface extraction and upgrading processes of western tar sands are described. Research areas included modified hot water, fluidized bed, and rotary kiln pyrolysis of tar sands for extraction of bitumen. Bitumen upgrading included solvent extraction of bitumen, and catalytic hydrotreating of bitumen. Characterization of Utah tar sand deposits is also included.

  12. Varying properties of in situ heat treatment of a tar sands formation based on assessed viscosities

    DOEpatents

    Karanikas, John Michael; Vinegar, Harold J

    2014-03-04

    A method for treating a tar sands formation includes providing heat to at least part of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. The heat is allowed to transfer from the heaters to at least a portion of the formation. A viscosity of one or more zones of the hydrocarbon layer is assessed. The heating rates in the zones are varied based on the assessed viscosities. The heating rate in a first zone of the formation is greater than the heating rate in a second zone of the formation if the viscosity in the first zone is greater than the viscosity in the second zone. Fluids are produced from the formation through the production wells.

  13. Coal Tar and Coal-Tar Pitch

    Cancer.gov

    Learn about coal-tar products, which can raise your risk of skin cancer, lung cancer, and other types of cancer. Examples of coal-tar products include creosote, coal-tar pitch, and certain preparations used to treat skin conditions such as eczema, psoriasis, and dandruff.

  14. Modeling the impact of bubbling bed hydrodynamics on tar yield and its fluctuations during biomass fast pyrolysis

    DOE PAGES

    Xiong, Qingang; Ramirez, Emilio; Pannala, Sreekanth; ...

    2015-10-09

    The impact of bubbling bed hydrodynamics on temporal variations in the exit tar yield for biomass fast pyrolysis was investigated using computational simulations of an experimental laboratory-scale reactor. A multi-fluid computational fluid dynamics model was employed to simulate the differential conservation equations in the reactor, and this was combined with a multi-component, multi-step pyrolysis kinetics scheme for biomass to account for chemical reactions. The predicted mean tar yields at the reactor exit appear to match corresponding experimental observations. Parametric studies predicted that increasing the fluidization velocity should improve the mean tar yield but increase its temporal variations. Increases in themore » mean tar yield coincide with reducing the diameter of sand particles or increasing the initial sand bed height. However, trends in tar yield variability are more complex than the trends in mean yield. The standard deviation in tar yield reaches a maximum with changes in sand particle size. As a result, the standard deviation in tar yield increases with the increases in initial bed height in freely bubbling state, while reaches a maximum in slugging state.« less

  15. Silica removal from steamflood-produced water: South Texas tar sands pilot

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Thomas, S.A.; Yost, M.E.; Cathey, S.R.

    1987-05-01

    Steamflood-produced waters commonly contain suspended solids, oil, hardness-causing minerals, sulfide, and silica. Removal of these contaminants would make many of these waters suitable for recycling as steamer feedwater. Reuse of steamflood-produced waters increases steamer feedwater supplies and reduces water disposal requirements. This paper describes a field pilot study of silica removal from steamflood-produced water in the south Texas tar sands region. A hot-lime precipitation process was used to reduce dissolved silica (SiO/sub 2/) concentrations from 400 to less than 50 mg/L SiO/sub 2/ in Mary R. Saner Ranch produced water. Most water systems using hot-lime precipitation for silica removal requiremore » the addition of magnesium salt, as well as lime, to enhance silica removal. In this field study, however, addition of magnesium salt did not improve silica removal efficiency. Hydrated lime, CA(OH)/sub 2/, alone was sufficient to attain desired silica residual, 50 mg/L SiO/sub 2/. The dissolved silica adsorbed onto the CaCO/sub 3/ crystals formed by lime reacting with the alkalinity present in the produced water. Required lime dosage was approximately 900 mg/L Ca(OH)/sub 2/.« less

  16. Study on tar generated from downdraft gasification of oil palm fronds.

    PubMed

    Atnaw, Samson Mekbib; Kueh, Soo Chuan; Sulaiman, Shaharin Anwar

    2014-01-01

    One of the most challenging issues concerning the gasification of oil palm fronds (OPF) is the presence of tar and particulates formed during the process considering its high volatile matter content. In this study, a tar sampling train custom built based on standard tar sampling protocols was used to quantify the gravimetric concentration of tar (g/Nm3) in syngas produced from downdraft gasification of OPF. The amount of char, ash, and solid tar produced from the gasification process was measured in order to account for the mass and carbon conversion efficiency. Elemental analysis of the char and solid tar samples was done using ultimate analysis machine, while the relative concentration of the different compounds in the liquid tar was determined making use of a liquid gas chromatography (GC) unit. Average tar concentration of 4.928 g/Nm3 and 1.923 g/Nm3 was obtained for raw gas and cleaned gas samples, respectively. Tar concentration in the raw gas sample was found to be higher compared to results for other biomass materials, which could be attributed to the higher volatile matter percentage of OPF. Average cleaning efficiency of 61% which is comparable to that of sand bed filter and venturi scrubber cleaning systems reported in the literature was obtained for the cleaning system proposed in the current study.

  17. Study on Tar Generated from Downdraft Gasification of Oil Palm Fronds

    PubMed Central

    Atnaw, Samson Mekbib; Kueh, Soo Chuan; Sulaiman, Shaharin Anwar

    2014-01-01

    One of the most challenging issues concerning the gasification of oil palm fronds (OPF) is the presence of tar and particulates formed during the process considering its high volatile matter content. In this study, a tar sampling train custom built based on standard tar sampling protocols was used to quantify the gravimetric concentration of tar (g/Nm3) in syngas produced from downdraft gasification of OPF. The amount of char, ash, and solid tar produced from the gasification process was measured in order to account for the mass and carbon conversion efficiency. Elemental analysis of the char and solid tar samples was done using ultimate analysis machine, while the relative concentration of the different compounds in the liquid tar was determined making use of a liquid gas chromatography (GC) unit. Average tar concentration of 4.928 g/Nm3 and 1.923 g/Nm3 was obtained for raw gas and cleaned gas samples, respectively. Tar concentration in the raw gas sample was found to be higher compared to results for other biomass materials, which could be attributed to the higher volatile matter percentage of OPF. Average cleaning efficiency of 61% which is comparable to that of sand bed filter and venturi scrubber cleaning systems reported in the literature was obtained for the cleaning system proposed in the current study. PMID:24526899

  18. Silica removal from steamflood produced water: South Texas Tar Sands Pilot

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Thomas, S.A.; Cathey, S.R.; Yost, M.E.

    1984-09-01

    Steamflood produced waters commonly contain suspended solids, oil, hardness, sulfide, and silica. Removal of these contaminants would make many of these waters suitable candidates for recycling as steam feedwater. Reuse of steamflood produced waters will increase steamer feedwater supplies, as well as reduce water disposal requirements. This paper describes a field pilot study of silica removal from steamflood produced water in the South Texas Tar Sands region. A hot-lime precipitation process was used to reduce dissolved silica concentrations from 400 mg/l to less than 50 mg/l SiO/sub 2/ in Mary R. Saner Ranch produced water. Most water systems using hot-limemore » precipitation for silica removal call for the addition of magnesium salts, as well as lime, to enhance silica removal. In this field study, however, magnesium salt addition did not improve silica removal efficiency. Hydrated lime ((Ca(OH)/sub 2/), alone, was sufficient to attain the desired silica residual, 50 mg/l SiO/sub 2/. The dissolved silica adsorbed onto the CaCO/sub 3/ crystals formed by lime reacting with the alkalinity present in the produced water. Required lime dosage was approximately 900 mg/lCa(OH)/sub 2/. Residual silica concentrations were found to be strongly related to both precipitator pH and calcium ion concentration. Therefore, on-line pH and hardness monitoring may be used to estimate and control residual silica concentration. A 50,000-BPD (7,900 m/sup 3//d) produced water treating plant has been designed using results from this pilot study.« less

  19. Hydrocarbon accumulation in Pennsylvanian-age Ten Sleep Sandstone: the Trapper Creek tar sand deposit, Big Horn basin, Wyoming

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barrell, S.S.

    1983-03-01

    Preliminary investigations indicate a potential tar sand accumulation in the Trapper Creek deposit of more than 2.13 million tons of mineralized material with a yield of 0.92 bbl per ton of 5.2/sup 0/ API oil for an approximate resource of 1.96 million bbl of recoverable petroleum. Remote sensing data suggest that the accumulation is in part controlled by two major and four minor lineaments which traverse the area. Stratigraphic and lithologic criteria can be used to infer a Minnelusa-type mode of occurrence. Ancillary stream sediment and outcrop geochemistry data yield locally anomalous but uneconomic concentrations of Mg, Ca, Ti, Mn,more » Ag, Cu, Mo, V, K, and Si, which may have significance in the identification of similar hydrocarbon accumulations along the west flank of the Bighorn Mountains.« less

  20. Investigation of Reversing Sand Dunes at the Bruneau Dunes, Idaho, as Analogs for Features on Mars

    NASA Astrophysics Data System (ADS)

    Zimbelman, J. R.; Scheidt, S. P.

    2012-12-01

    The Bruneau Dunes in south-central Idaho include several large reversing sand dunes located within a cut-off meander of the Snake River. These dunes include the largest single-structured sand dune present in North America. Wind records from the Remote Automated Weather Station (RAWS) installation at the Mountain Home Air Force Base, which is ~21 km NW of the Bruneau Dunes, have proved to be very helpful in assessing the regional wind patterns at this section of the western Snake River Plains province; a bimodal wind regime is present, with seasonal changes of strong (sand-moving) winds blowing from either the northwest or the southeast. During April of 2011, we obtained ten precision topographic surveys across the southernmost reversing dune using a Differential Global Positioning System (DGPS). The DGPS data document the shape of the dune going from a low, broad sand ridge at the southern distal end of the dune to the symmetrically shaped 112-m-high central portion of the dune, where both flanks of the dune consist of active slopes near the angle of repose. These data will be useful in evaluating the reversing dune hypothesis proposed for enigmatic features on Mars called Transverse Aeolian Ridges (TARs), which could have formed either as large mega-ripples or small sand dunes. The symmetric profiles across TARs with heights greater than 1 m are more consistent with measured profiles of reversing sand dunes than with measured profiles of mega-ripples (whose surfaces are coated by large particles ranging from coarse sand to gravel, moved by saltation-induced creep). Using DGPS to monitor changes in the three-dimensional location of the crests of the reversing dunes at the Bruneau Dunes should provide a means for estimating the likely timescale for changes of TAR crests if the Martian features are indeed formed in the same manner as reversing sand dunes on Earth.

  1. Coal tar phototherapy for psoriasis reevaluated: erythemogenic versus suberythemogenic ultraviolet with a tar extract in oil and crude coal tar

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lowe, N.J.; Wortzman, M.S.; Breeding, J.

    1983-06-01

    Recent studies have questioned the therapeutic value of coal tar versus ultraviolet (UV) radiation and their relative necessity in phototherapy for psoriasis. In this investigation, different aspects of tar phototherapy have been studied in single-blind bilateral paired comparison studies. The effects of 1% crude coal tar were compared with those of petrolatum in conjunction with erythemogenic and suberythemogenic doses of ultraviolet light (UVB) using a FS72 sunlamp tubed cabinet. Crude coal tar was clinically superior to petrolatum with suberythemogenic ultraviolet. With the erythemogenic UVB, petrolatum was equal in efficacy to crude coal tar. Suberythemogenic UVB was also used adjunctively tomore » compare the effects of a 5% concentration of a tar extract in an oil base to 5% crude coal tar in petrolatum or the oil base without tar. The tar extract in oil plus suberythemogenic UVB produced significantly more rapid improvement than the oil base plus UVB. The direct bilateral comparison of equal concentrations of tar extract in oil base versus crude coal tar in petrolatum in a suberythemogenic UV photo regimen revealed no statistical differences between treatments. In a study comparing tar extract in oil and the oil base without ultraviolet radiation, the tar extract in oil side responded more rapidly.« less

  2. River of Sand

    NASA Image and Video Library

    2016-09-21

    A dominant driver of surface processes on Mars today is aeolian (wind) activity. In many cases, sediment from this activity is trapped in low-lying areas, such as craters. Aeolian features in the form of dunes and ripples can occur in many places on Mars depending upon regional wind regimes. The Cerberus Fossae are a series of discontinuous fissures along dusty plains in the southeastern region of Elysium Planitia. This rift zone is thought to be the result of combined volcano-tectonic processes. Dark sediment has accumulated in areas along the floor of these fissures as well as inactive ripple-like aeolian bedforms known as "transverse aeolian ridges" (TAR). Viewed through HiRISE infrared color, the basaltic sand lining the fissures' floor stands out as deep blue against the light-toned dust covering the region. This, along with the linearity of the fissures and the wave-like appearance of the TAR, give the viewer an impression of a river cutting through the Martian plains. However, this river of sand does not appear to be flowing. Analyses of annual monitoring images of this region have not detected aeolian activity in the form of ripple migration thus far. http://photojournal.jpl.nasa.gov/catalog/PIA21063

  3. Tar removal during the fluidized bed gasification of plastic waste.

    PubMed

    Arena, Umberto; Zaccariello, Lucio; Mastellone, Maria Laura

    2009-02-01

    A recycled polyethylene was fed in a pilot plant bubbling fluidized bed gasifier, having an internal diameter of 0.381 m and a maximum feeding capacity of 90 kg/h. The experimental runs were carried out under various operating conditions: the bed temperature was kept at about 850 degrees C, the equivalence ratio varied between 0.2 and 0.35, the amount of bed material was between 131 and 215 kg, the fluidizing velocity was between 0.5 and 0.7 m/s, quartz sand and olivine were used as bed material, and air and steam were used as fluidizing reactants. The results confirm that the tar removal treatments applied inside the gasifier (primary methods) can eliminate or strongly reduce the need for a further downstream cleanup of the syngas. In particular, the utilization of a natural olivine as an in situ tar reduction agent remarkably improves the quality of the product gas, in terms of both high hydrogen volumetric fraction and larger syngas yield.

  4. Low-tar and high-tar cigarettes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Holt, P.G.; Chalmer, J.E.; Roberts, L.M.

    Mice were exposed for 7 to 8 minutes on weekdays to fresh smoke from high-tar (HT) or low-tar (LT) cigarettes for varying periods of up to 36 weeks. Mice exposed to HT cigarettes exhibited more marked alterations in humoral immune responsiveness, hematological profiles, and pulmonary pathologic findings than those exposed to LT cigarettes. However, cell-mediated immune responsiveness to both bacterial and tumor-specific antigens was depressed similarly in animals exposed to HT or LT cigarettes. Furthermore, the growth rates of subcutaneously established tumors were enhanced similarly in the two groups, with respect to those in control animals.

  5. Influence of the presence of PAHs and coal tar on naphthalene sorption in soils

    NASA Astrophysics Data System (ADS)

    Bayard, Rémy; Barna, Ligia; Mahjoub, Borhane; Gourdon, Rémy

    2000-11-01

    concentrations (about 120 mg/kg) in the soil. In contrast, experiments carried out with coal tar particles revealed a significant effect. Naphthalene sorption appeared to be proportional to the amount of coal tar added to the sand or soil, and a much higher affinity of naphthalene for XOM ( Koc above 2000 cm 3/g) than SOM ( Koc around 300 cm 3/g) was observed. Naphthalene transport in the columns of sand or soil spiked with coal tar particles was simulated very satisfactorily with a dual double-domain model. Around 90% of naphthalene retention by coal tar was found to occur within the organic phase, suggesting a phase partition process which may be explained by the amorphous nature of the XOM and its extreme affinity for naphthalene. For SOM, however, which is present as porous microaggregates of clay and humic substances, with less affinity for naphthalene, only 1/3 of naphthalene retention was found to occur within the organic phase, underlining the significant role of surface adsorption in the short term behavior of naphthalene in soil. For longer contact times, the model simulations proposed in the present study should be coupled to slow sorption, aging and biodegradation models to describe long-term behavior of naphthalene in soil-tar-water systems.

  6. The extraction of bitumen from western oil sands. Annual report, July 1991--July 1992

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Oblad, A.G.; Bunger, J.W.; Dahlstrom, D.A.

    1992-08-01

    The University of Utah tar sand research and development program is concerned with research and development on Utah is extensive oil sands deposits. The program has been intended to develop a scientific and technological base required for eventual commercial recovery of the heavy oils from oil sands and processing these oils to produce synthetic crude oil and other products such as asphalt. The overall program is based on mining the oil sand, processing the mined sand to recover the heavy oils and upgrading them to products. Multiple deposits are being investigated since it is believed that a large scale (approximatelymore » 20,000 bbl/day) plant would require the use of resources from more than one deposit. The tasks or projects in the program are organized according to the following classification: Recovery technologies which includes thermal recovery methods, water extraction methods, and solvent extraction methods; upgrading and processing technologies which covers hydrotreating, hydrocracking, and hydropyrolysis; solvent extraction; production of specialty products; and environmental aspects of the production and processing technologies. These tasks are covered in this report.« less

  7. Sydney Tar Ponds Remediation: Experience to China

    ERIC Educational Resources Information Center

    Liu, Fan; Bryson, Ken A.

    2009-01-01

    The infamous "Sydney Tar Ponds" are well known as one of the largest toxic waste sites of Canada, due to almost 100 years of steelmaking in Sydney, a once beautiful and peaceful city located on the east side of Cape Breton Island, Nova Scotia. This article begins with a contextual overview of the Tar Ponds issue including a brief…

  8. The Australian tar derby: the origins and fate of a low tar harm reduction programme

    PubMed Central

    King, W; Carter, S; Borland, R; Chapman, S; Gray, N

    2003-01-01

    Objective: To document the development of the low tar harm reduction programme in Australia, including tobacco industry responses. Data sources: Tobacco industry documents, retail tobacco journals, newspapers, medical journals, and Anti-Cancer Council of Victoria (ACCV) newsletters and archival records. Study selection: Documents on the strategies and knowledge bases of the ACCV, other Australian health authorities, and the tobacco industry. Results: The ACCV built a durable system for measuring and publicising the tar and nicotine yields of Australian cigarettes and influencing their development. The tobacco industry initially sought to block the development of this system but later appeared to cooperate with it, as is evidenced by the current market dominance of low tar brands. However, behind the scenes, the industry used its substantial knowledge advantage regarding compensatory smoking and its ability to re-engineer cigarettes to gain effective control of the system and subvert the ACCV's objectives. Conclusions: Replacement of the low tar programme with new means of minimising the harms from cigarette smoking should be a policy priority for the Australian government. This will require regulation, rather than further voluntary agreements, and stringent monitoring of successor programmes will be necessary. PMID:14645950

  9. Topical tar: Back to the future

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Paghdal, K.V.; Schwartz, R.A.

    2009-08-15

    The use of medicinal tar for dermatologic disorders dates back to the ancient times. Although coal tar is utilized more frequently in modern dermatology, wood tars have also been widely employed. Tar is used mainly in the treatment of chronic stable plaque psoriasis, scalp psoriasis, atopic dermatitis, and seborrheic dermatitis, either alone or in combination therapy with other medications, phototherapy, or both. Many modifications have been made to tar preparations to increase their acceptability, as some dislike its odor, messy application, and staining of clothing. One should consider a tried and true treatment with tar that has led to clearingmore » of lesions and prolonged remission times. Occupational studies have demonstrated the carcinogenicity of tar; however, epidemiologic studies do not confirm similar outcomes when used topically. This article will review the pharmacology, formulations, efficacy, and adverse effects of crude coal tar and other tars in the treatment of selected dermatologic conditions.« less

  10. Characteristics of PAH tar oil contaminated soils-Black particles, resins and implications for treatment strategies.

    PubMed

    Trellu, Clément; Miltner, Anja; Gallo, Rosita; Huguenot, David; van Hullebusch, Eric D; Esposito, Giovanni; Oturan, Mehmet A; Kästner, Matthias

    2017-04-05

    Tar oil contamination is a major environmental concern due to health impacts of polycyclic aromatic hydrocarbons (PAH) and the difficulty of reaching acceptable remediation end-points. Six tar oil-contaminated soils with different industrial histories were compared to investigate contamination characteristics by black particles. Here we provide a simple method tested on 6 soils to visualize and identify large amounts of black particles (BP) as either solid aggregates of resinified and weathered tar oil or various wood/coke/coal-like materials derived from the contamination history. These materials contain 2-10 times higher PAH concentrations than the average soil and were dominantly found in the sand fraction containing 42-86% of the total PAH. The PAH contamination in the different granulometric fractions was directly proportional to the respective total organic carbon content, since the PAH were associated to the carbonaceous particulate materials. Significantly lower (bio)availability of PAH associated to these carbonaceous phases is widely recognized, thus limiting the efficiency of remediation techniques. We provide a conceptual model of the limited mass transfer of PAH from resinated tar oil phases to the water phase and emphasize the options to physically separate BP based on their lower bulk density and slower settling velocity. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. 29 CFR 1910.1002 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 6 2013-07-01 2013-07-01 false Coal tar pitch volatiles; interpretation of term. 1910.1002... Hazardous Substances § 1910.1002 Coal tar pitch volatiles; interpretation of term. As used in § 1910.1000 (Table Z-1), coal tar pitch volatiles include the fused polycyclic hydrocarbons which volatilize from the...

  12. 29 CFR 1910.1002 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 6 2010-07-01 2010-07-01 false Coal tar pitch volatiles; interpretation of term. 1910.1002... Hazardous Substances § 1910.1002 Coal tar pitch volatiles; interpretation of term. As used in § 1910.1000 (Table Z-1), coal tar pitch volatiles include the fused polycyclic hydrocarbons which volatilize from the...

  13. 29 CFR 1910.1002 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 6 2011-07-01 2011-07-01 false Coal tar pitch volatiles; interpretation of term. 1910.1002... Hazardous Substances § 1910.1002 Coal tar pitch volatiles; interpretation of term. As used in § 1910.1000 (Table Z-1), coal tar pitch volatiles include the fused polycyclic hydrocarbons which volatilize from the...

  14. 29 CFR 1910.1002 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 6 2012-07-01 2012-07-01 false Coal tar pitch volatiles; interpretation of term. 1910.1002... Hazardous Substances § 1910.1002 Coal tar pitch volatiles; interpretation of term. As used in § 1910.1000 (Table Z-1), coal tar pitch volatiles include the fused polycyclic hydrocarbons which volatilize from the...

  15. 29 CFR 1910.1002 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 6 2014-07-01 2013-07-01 true Coal tar pitch volatiles; interpretation of term. 1910.1002... Hazardous Substances § 1910.1002 Coal tar pitch volatiles; interpretation of term. As used in § 1910.1000 (Table Z-1), coal tar pitch volatiles include the fused polycyclic hydrocarbons which volatilize from the...

  16. The temporal relationship between advertising and sales of low-tar cigarettes.

    PubMed

    Reed, Mark B; Anderson, Christy M; Burns, David M

    2006-12-01

    To determine whether a temporal relationship exists between the advertising and sales of low-tar cigarettes. It was hypothesised that increases in the advertising of low-tar cigarettes would precede increases in sales for these cigarettes. The themes of cigarette advertisements were reviewed and coded for 20 low-tar cigarette brands advertised in 13 widely read magazines in the US between 1960 and 1996. These 20 brands represented most of the low-tar cigarette advertisements and cigarette sales from 1967 to 1996. Cigarette sales data were obtained from the 1994 Maxwell report that summarises all cigarette sales from 1925 to 1990. If the advertisement referred to the low-tar attributes of the cigarette advertised, the advertisement was coded as having a low-tar theme and was included in the analysis. Five different graphical presentations of the relationship between the advertising and sales of the 20 low-tar cigarette brands showed a temporal relationship between low-tar advertising and sales for these brands. This relationship was observed for brands that introduced a low-tar alternative into an existing brand family (eg, Marlboro Light) and for new exclusively low-tar brands (eg, Carlton). Despite large increases in the advertising for the exclusively low-tar brands, sales of these brands remained low relative to sales of the low-tar alternative brands. Increases in print advertising of 20 of the most popular low-tar cigarette brands were followed by increases in sales for these cigarettes. Despite increases in the advertising of exclusively low-tar brands in the mid-1970s and early 1980s, the sales of these brands never matched the sales of the low-tar alternative brands. This suggests that it may have been easier to get smokers to switch to low-tar brands within a brand family compared with entirely new low-tar brands. Over the past 30 years, the marketing of low-tar cigarettes as a healthier alternative to higher-tar cigarettes has resulted in these brands

  17. The temporal relationship between advertising and sales of low‐tar cigarettes

    PubMed Central

    Reed, Mark B; Anderson, Christy M; Burns, David M

    2006-01-01

    Objective and hypothesis To determine whether a temporal relationship exists between the advertising and sales of low‐tar cigarettes. It was hypothesised that increases in the advertising of low‐tar cigarettes would precede increases in sales for these cigarettes. Methods The themes of cigarette advertisements were reviewed and coded for 20 low‐tar cigarette brands advertised in 13 widely read magazines in the US between 1960 and 1996. These 20 brands represented most of the low‐tar cigarette advertisements and cigarette sales from 1967 to 1996. Cigarette sales data were obtained from the 1994 Maxwell report that summarises all cigarette sales from 1925 to 1990. If the advertisement referred to the low‐tar attributes of the cigarette advertised, the advertisement was coded as having a low‐tar theme and was included in the analysis. Results Five different graphical presentations of the relationship between the advertising and sales of the 20 low‐tar cigarette brands showed a temporal relationship between low‐tar advertising and sales for these brands. This relationship was observed for brands that introduced a low‐tar alternative into an existing brand family (eg, Marlboro Light) and for new exclusively low‐tar brands (eg, Carlton). Despite large increases in the advertising for the exclusively low‐tar brands, sales of these brands remained low relative to sales of the low‐tar alternative brands. Conclusions Increases in print advertising of 20 of the most popular low‐tar cigarette brands were followed by increases in sales for these cigarettes. Despite increases in the advertising of exclusively low‐tar brands in the mid‐1970s and early 1980s, the sales of these brands never matched the sales of the low‐tar alternative brands. This suggests that it may have been easier to get smokers to switch to low‐tar brands within a brand family compared with entirely new low‐tar brands. Over the past 30 years, the marketing of low‐tar

  18. Atmospheric tar balls from biomass burning in Mexico

    NASA Astrophysics Data System (ADS)

    Adachi, K.; Buseck, P. R.

    2009-12-01

    Tar balls are spherical, organic aerosol particles that result from biofuel or biomass burning. They absorb sunlight and cause warming of the atmosphere. Although distinctive when viewed with a transmission electron microscope (TEM) because of their spherical shape, much remains to be determined about details of their compositions, occurrences, and generation. Here we aim to characterize the occurrences of tar balls using individual-particle analyses with a TEM and to study their formation in young biomass-burning smoke. The samples were collected using the U.S. Forest Service Twin Otter aircraft during the MILAGRO (Megacity Initiative: Local and Global Research Observations) campaign conducted in March 2006. We analyzed 84 TEM grid samples from ~30 biomass-burning events near Mexico City and over Yucatan. Sixty samples were from young smoke (less than an hour old), and others were from haze that mainly occurred from biomass burning. Tar balls have neither an evident nucleus nor are they normally attached to other particles. They are almost perfectly spherical on TEM grids, indicating that they were solid when collected. It appears as if tar balls consist of lower volatility organic matter than many other organic aerosol particles. On average, 9% by number of biomass-burning aerosol particles were tar balls in samples collected between a few minutes to an hour after emission. On the other hand, samples collected within a few minutes after emission included few or no tar balls. The occurrences and abundances of atmospheric tar balls are important when evaluating the effects of smoke on local and regional climate.

  19. Natural radioactivity of the tar-sand deposits of Ondo State, Southwestern Nigeria

    NASA Astrophysics Data System (ADS)

    Fasasi, M. K.; Oyawale, A. A.; Mokobia, C. E.; Tchokossa, P.; Ajayi, T. R.; Balogun, F. A.

    2003-06-01

    A combination of gamma spectrometry and energy dispersive X-ray fluorescence was used to determine the presence and level of radioactivity of radionuclides in bituminous sand and overburden obtained from bituminous sand deposits in Ondo State Nigeria for the purpose of providing baseline data and assessing its impact on the environment. The radionuclides identified with reliable regularity belong to the decay series of naturally occurring radionuclides headed by 238U and 232Th. The non-decay series of naturally occurring 40K was found to be below the limit of detection. The average specific activity concentration values obtained for 214 Bi, 208Tl, and 226Ra in the overburden are 165.64±2.91, 150.25±2.91 and 60.97±2.27 Bq kg -1, respectively. The measured activity in the bituminous sand layer is so low that it can be said to be non-radioactive. The result of the EDXRF supports the presence of radioelements in the overburden, which are likely to be embedded in accessory minerals like zircon and tourmaline. Thus, surface exploration technique using soil-gas radon measurement will not yield the desired result. Furthermore, the level of radioelements and associated decay daughter 222Rn is not expected to cause any health hazard.

  20. Fractal-like Tar Ball Aggregates from Wildfire Smoke

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Girotto, Giulia; China, Swarup; Bhandari, Janarjan

    Tar balls are atmospheric particles abundant in slightly aged biomass burning smoke and have a significant, but highly uncertain, role on Earth's radiative balance. Tar balls are typically detected using electron microscopy; they are resistant to the electron beam, and generally, they are observed as individual spheres. Here, we report new observations of a significant fraction of tar ball aggregates (~27% by number) from samples collected in a plume of the Whitewater-Baldy Complex fire in New Mexico. The structure of these aggregates is fractal-like and follows a scale invariant power law similar to that of soot particles, despite the considerablymore » larger size and smaller number of monomers. We also present observations of tar ball aggregates from four other geographical locations, including from a remote high elevation site in the North Atlantic Ocean. Aggregation affects the particle optical properties and therefore, their climatic impact. We performed numerical simulations based on the observed morphology and estimated the effects of aggregation on the tar balls optical properties. We find that aggregation can enhance single scattering albedo by up to 41%.« less

  1. Final safety assessment of Coal Tar as used in cosmetics.

    PubMed

    2008-01-01

    were genotoxic in bacterial assays. Coal Tar was genotoxic in a mammalian genotoxicity assay and induced DNA adducts in various tissue types. Chronic exposure of mice to Coal Tar significantly decreased survival and liver neoplasms were seen in a significant dose-related trend; in other studies using mice lung tumors and perianal skin cancers were found. Coal Tar was comedogenic in three small clinical studies. Folliculitis is associated with the prolonged use of some tars. Several published reports describe cases of contact sensitivity to Coal Tar. Polycyclic aromatic hydrocarbons, which make up Coal Tar, are photosensitizers and cause phototoxicity by an oxygen-dependent mechanism. A retrospective study of the reproductive toxicity of Coal Tar in humans compared exposed women to controls and found little difference in spontaneous abortion and congenital disorders. Cancer epidemiology studies of patients who have received Coal Tar therapy of one form or other have failed to link treatment with an increase in the risk of cancer. Although the Cosmetic Ingredient Review (CIR) Expert Panel believes that Coal Tar use as an antidandruff ingredient in OTC drug preparations is adequately addressed by the FDA regulations, the Panel also believes that the appropriate concentration of use of Coal Tar in cosmetic formulations should be that level that does not have a biological effect in the user. Additional data needed to make a safety assessment include product types in which Coal Tar is used (other than as an OTC drug ingredient), use concentrations, and the maximum concentration that does not induce a biological effect in users.

  2. Process for hydrogenation of hydrocarbon tars

    DOEpatents

    Dolbear, Geoffrey E.

    1978-07-18

    Hydrocarbon tars of high asphaltene content such as tars obtained from pyrolysis of coal are dissolved in a solvent formed from the hydrogenation of the coal tars, and the resultant mixture hydrogenated in the presence of a catalyst at a pressure from about 1500 to 5000 psig at a temperature from about 500.degree. F to about the critical temperature of the solvent to form a light hydrocarbon as a solvent for the tars. Hydrogen content is at least three times the amount of hydrogen consumed.

  3. Method for treatment of tar-bearing fuel gas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Frauen, L.L.; Kasper, S.

    1986-01-07

    A process is described of producing a fuel gas which contains condensable tar vapor when it leaves a gasifier, the improvement wherein the tar-bearing gases are treated to remove tar therefrom. The process consists of: (a) continuously conducting hot fuel gas from a gasifier to and discharging it into a spray chamber where the hot tar-bearing gas is contacted with a fine spray of water thereby cooling the tar vapor and evaporating the water to produce a fog-like dispersion of tar in an atmosphere of fuel gas with the temperature in the spray chamber maintained above the dew point ofmore » water; (b) continuously transferring the fuel gas and the dispersion of tar and water to an electrostatic precipitator and precipitating therein at least most of the condensed tar as a liquid; (c) removing the liquid tar so precipitated and conducting at least most of it to a tar burner; (d) burning the tar with no more than the stoichiometric supply of oxygen provided by air to produce oxygen-free and tar-free hot combustion gases; (e) conducting the hot combustion gases directly into a mixer into which the fuel gas and water vapor flows from the precipitator, thereby adding to the fuel gas the sensible heat of the combustion gases; and (f) conducting the mixture so produced to a place of use as a hot fuel gas mixture.« less

  4. Heat-resistant agent used for control sand of steam huff and puff heavy oil well

    NASA Astrophysics Data System (ADS)

    Zhang, F. S.; Liu, G. L.; Lu, Y. J.; Xiong, X. C.; Ma, J. H.; Su, H. M.

    2018-01-01

    Heat-resistant agent containing hydroxymethyl group was synthesized from coal tar, which has similar structure with phenolic resin and could improve the heat resistance of phenolic resin sand control agent. The results showed that the heat resistance of the sand control agent was improved by adding 10% to 30% heat-resistant agent, after 280°C high temperature treatment for 7d, the compressive strength of consolidated core was increased to more than 5MPa. The compressive strength of consolidation core was not decreased after immersion in formation water, crude oil, acid or alkaline medium, which showed good resistance to medium immersion. The sand control agent had small core damage and the core permeability damage ratio of sand control agent consolidation was only 18.7%.

  5. Integrated Biomass Gasification with Catalytic Partial Oxidation for Selective Tar Conversion

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Lingzhi; Wei, Wei; Manke, Jeff

    economics analysis. Major milestones include identification of syngas cleaning requirements for proposed system design, identification and selection of tar compounds and 2 mixtures for use in CPO tests, and preparation of CPO catalysts for validation. (Q3 2009 ~ Q4 2009) - Task C: Test CPO with biomass gasification product gas. Optimize CPO performance with selected tar compounds. Optimize CPO performance with multi-component mixtures. Milestones include optimizing CPO catalysts design, collecting CPO experimental data for next stage kinetic modeling and understanding the effect of relative reactivities on ultimate tar conversion and syngas yields. (Q1 2010 ~ Q3 2010) - Task D: Develop tar CPO kinetic model with CPO kinetic model and modeling results as deliverables. (Q3 2010 ~ Q2 2011) - Task E: Project management and reporting. Milestone: Quarterly reports and presentations, final report, work presented at national technical conferences (Q1 2009 ~ Q2 2011) At the beginning of the program, IP landscaping was conducted to understand the operation of various types of biomass gasifiers, their unique syngas/tar compositions and potential tar mitigation options using the catalytic partial oxidation technology. A process simulation model was developed to quantify the system performance and economics impact of CPO tar removal technology. Biomass gasification product compositions used for performance evaluation tests were identified after literature review and system modeling. A reaction system for tar conversion tests was designed, constructed, with each individual component shaken-down in 2009. In parallel, University of Minnesota built a lab-scale unit and evaluated the tar removal performance using catalytic reforming. Benzene was used as the surrogate compound. The biomass gasification raw syngas composition was provided by GE through system studies. In 2010, GE selected different tar compounds and evaluated the tar removal effectiveness of the CPO catalyst. The catalytic

  6. Metal catalysts for steam reforming of tar derived from the gasification of lignocellulosic biomass.

    PubMed

    Li, Dalin; Tamura, Masazumi; Nakagawa, Yoshinao; Tomishige, Keiichi

    2015-02-01

    Biomass gasification is one of the most important technologies for the conversion of biomass to electricity, fuels, and chemicals. The main obstacle preventing the commercial application of this technology is the presence of tar in the product gas. Catalytic reforming of tar appears a promising approach to remove tar and supported metal catalysts are among the most effective catalysts. Nevertheless, improvement of catalytic performances including activity, stability, resistance to coke deposition and aggregation of metal particles, as well as catalyst regenerability is greatly needed. This review focuses on the design and catalysis of supported metal catalysts for the removal of tar in the gasification of biomass. The recent development of metal catalysts including Rh, Ni, Co, and their alloys for steam reforming of biomass tar and tar model compounds is introduced. The role of metal species, support materials, promoters, and their interfaces is described. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Coal tar induces AHR-dependent skin barrier repair in atopic dermatitis

    PubMed Central

    van den Bogaard, Ellen H.; Bergboer, Judith G.M.; Vonk-Bergers, Mieke; van Vlijmen-Willems, Ivonne M.J.J.; Hato, Stanleyson V.; van der Valk, Pieter G.M.; Schröder, Jens Michael; Joosten, Irma; Zeeuwen, Patrick L.J.M.; Schalkwijk, Joost

    2013-01-01

    Topical application of coal tar is one of the oldest therapies for atopic dermatitis (AD), a T helper 2 (Th2) lymphocyte–mediated skin disease associated with loss-of-function mutations in the skin barrier gene, filaggrin (FLG). Despite its longstanding clinical use and efficacy, the molecular mechanism of coal tar therapy is unknown. Using organotypic skin models with primary keratinocytes from AD patients and controls, we found that coal tar activated the aryl hydrocarbon receptor (AHR), resulting in induction of epidermal differentiation. AHR knockdown by siRNA completely abrogated this effect. Coal tar restored filaggrin expression in FLG-haploinsufficient keratinocytes to wild-type levels, and counteracted Th2 cytokine–mediated downregulation of skin barrier proteins. In AD patients, coal tar completely restored expression of major skin barrier proteins, including filaggrin. Using organotypic skin models stimulated with Th2 cytokines IL-4 and IL-13, we found coal tar to diminish spongiosis, apoptosis, and CCL26 expression, all AD hallmarks. Coal tar interfered with Th2 cytokine signaling via dephosphorylation of STAT6, most likely due to AHR-regulated activation of the NRF2 antioxidative stress pathway. The therapeutic effect of AHR activation herein described opens a new avenue to reconsider AHR as a pharmacological target and could lead to the development of mechanism-based drugs for AD. PMID:23348739

  8. Coal tar induces AHR-dependent skin barrier repair in atopic dermatitis.

    PubMed

    van den Bogaard, Ellen H; Bergboer, Judith G M; Vonk-Bergers, Mieke; van Vlijmen-Willems, Ivonne M J J; Hato, Stanleyson V; van der Valk, Pieter G M; Schröder, Jens Michael; Joosten, Irma; Zeeuwen, Patrick L J M; Schalkwijk, Joost

    2013-02-01

    Topical application of coal tar is one of the oldest therapies for atopic dermatitis (AD), a T helper 2 (Th2) lymphocyte-mediated skin disease associated with loss-of-function mutations in the skin barrier gene, filaggrin (FLG). Despite its longstanding clinical use and efficacy, the molecular mechanism of coal tar therapy is unknown. Using organotypic skin models with primary keratinocytes from AD patients and controls, we found that coal tar activated the aryl hydrocarbon receptor (AHR), resulting in induction of epidermal differentiation. AHR knockdown by siRNA completely abrogated this effect. Coal tar restored filaggrin expression in FLG-haploinsufficient keratinocytes to wild-type levels, and counteracted Th2 cytokine-mediated downregulation of skin barrier proteins. In AD patients, coal tar completely restored expression of major skin barrier proteins, including filaggrin. Using organotypic skin models stimulated with Th2 cytokines IL-4 and IL-13, we found coal tar to diminish spongiosis, apoptosis, and CCL26 expression, all AD hallmarks. Coal tar interfered with Th2 cytokine signaling via dephosphorylation of STAT6, most likely due to AHR-regulated activation of the NRF2 antioxidative stress pathway. The therapeutic effect of AHR activation herein described opens a new avenue to reconsider AHR as a pharmacological target and could lead to the development of mechanism-based drugs for AD.

  9. 40 CFR 721.10532 - Tar, brown coal.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Tar, brown coal. 721.10532 Section 721... Tar, brown coal. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as tar, brown coal (PMN P-12-167, CAS No. 101316-83-0) is subject to...

  10. 40 CFR 721.10532 - Tar, brown coal.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Tar, brown coal. 721.10532 Section 721... Tar, brown coal. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as tar, brown coal (PMN P-12-167, CAS No. 101316-83-0) is subject to...

  11. Timing and petroleum sources for the Lower Cretaceous Mannville Group oil sands of northern Alberta based on 4-D modeling

    USGS Publications Warehouse

    Higley, D.K.; Lewan, M.D.; Roberts, L.N.R.; Henry, M.

    2009-01-01

    The Lower Cretaceous Mannville Group oil sands of northern Alberta have an estimated 270.3 billion m3 (BCM) (1700 billion bbl) of in-place heavy oil and tar. Our study area includes oil sand accumulations and downdip areas that partially extend into the deformation zone in western Alberta. The oil sands are composed of highly biodegraded oil and tar, collectively referred to as bitumen, whose source remains controversial. This is addressed in our study with a four-dimensional (4-D) petroleum system model. The modeled primary trap for generated and migrated oil is subtle structures. A probable seal for the oil sands was a gradual updip removal of the lighter hydrocarbon fractions as migrated oil was progressively biodegraded. This is hypothetical because the modeling software did not include seals resulting from the biodegradation of oil. Although the 4-D model shows that source rocks ranging from the Devonian-Mississippian Exshaw Formation to the Lower Cretaceous Mannville Group coals and Ostracode-zone-contributed oil to Mannville Group reservoirs, source rocks in the Jurassic Fernie Group (Gordondale Member and Poker Chip A shale) were the initial and major contributors. Kinetics associated with the type IIS kerogen in Fernie Group source rocks resulted in the early generation and expulsion of oil, as early as 85 Ma and prior to the generation from the type II kerogen of deeper and older source rocks. The modeled 50% peak transformation to oil was reached about 75 Ma for the Gordondale Member and Poker Chip A shale near the west margin of the study area, and prior to onset about 65 Ma from other source rocks. This early petroleum generation from the Fernie Group source rocks resulted in large volumes of generated oil, and prior to the Laramide uplift and onset of erosion (???58 Ma), which curtailed oil generation from all source rocks. Oil generation from all source rocks ended by 40 Ma. Although the modeled study area did not include possible western

  12. Groundwater contamination by organic bases derived from coal-tar wastes

    USGS Publications Warehouse

    Pereira, W.E.; Rostad, C.E.; Garbarino, J.R.; Hult, M.F.

    1983-01-01

    A fluid sample from a shallow aquifer contaminated by coal-tar wastes was analyzed for organic bases. The sample consisted of a mixture of aqueous and oily-tar phases. The phases were separated by centrifugation and filtration. Organic bases were isolated from each phase by pH adjustment and solvent extraction. Organic bases in the oily-tar phase were further purified by neutral-alumina, micro-column adsorption chromatography. Separation and identification of the organic bases in each phase were achieved by using capillary gas chromatography-mass spectrometry-computer (GC-MS-COM) and probe distillation-high resolution mass spectrometry (PD-HRMS) techniques. Organic bases present in the aqueous phase included primary aromatic amines (such as aniline, alkylated anilines, and naphthylamines) as well as azaarenes (such as alkylated pyridines, quinolines, acridine, and benzoquinolines). The oily-tar phase contained acridine, benzacridines, dibenzacridines, and numerous other azaarenes, the elemental compositions of which were determined by PD-HRMS. Azaarenes in the oily-tar phase, varying in size from 6 to 12 rings, are reported for the first time. The origin and environmental significance of these compounds are discussed. ?? 1983.

  13. Mineral resources of the San Rafael Swell Wilderness Study Areas, including Muddy Creek, Crack Canyon, San Rafael Reef, Mexican Mountain, and Sids Mountain Wilderness Study Areas, Emery County, Utah

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bartsch-Winkler, S.; Dickerson, R.P.; Barton, H.W.

    1990-09-01

    This paper reports on the San Rafael Swell Wilderness Study areas, which includes the Muddy Creek, Crack Canyon, San Rafael Reef, Mexican Mountain, and Sids Mountain Wilderness Study Areas, in Emery County, south-central Utah. Within and near the Crack Canyon Wilderness Study Area are identified subeconomic uranium and vanadium resources. Within the Carmel Formation are inferred subeconomic resources of gypsum in the Muddy Creek, San Rafael Reef, and Sids Mountain Wilderness Study Areas. Other commodities evaluated include geothermal energy, gypsum, limestone, oil and gas, sand and gravel, sandstone, semiprecious gemstones, sulfur petrified wood, and tar sand.

  14. Ground-water contamination by organic bases derived from coal-tar wastes

    USGS Publications Warehouse

    Pereira, Wilfred E.; Rostad, Colleen E.; Garbarino, John R.; Hult, Marc F.

    1983-01-01

    A fluid sample from a shallow aquifer contaminated by coal-tar wastes was analyzed for organic bases. The sample consisted of a mixture of aqueous and oily-tar phases. The phases were separated by centrifugation and filtration. Organic bases were isolated from each phase by pH adjustment and solvent extraction. Organic bases in the oily-tar phase were further purified by neutral-alumina, micro-column adsorption chromatography. Separation and identification of the organic bases in each phase were achieved by using capillary gas chromatography-mass spectrometry-computer (GC-MS-COM) and probe distillation-high resolution mass spectrometry (PD-HRMS) techniques. Organic bases present in the aqueous phase included primary aromatic amines (such as aniline, alkylated anilines, and naphthylamines) as well as azaarenes (such as alkylated pyridines, quinolines, acridine, and benzoquinolines). The oily-tar phase contained acridine, benzacridines, dibenzacridines, and numerous other azaarenes, the elemental compositions of which were determined by PD-HRMS. Azaarenes in the oily-tar phase, varying in size from 6 to 12 rings, are reported for the first time. The origin and environmental significance of these compounds are discussed.

  15. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Murphey, P. C.; Daitch, D.; Environmental Science Division

    In August 2005, the U.S. Congress enacted the Energy Policy Act of 2005, Public Law 109-58. In Section 369 of this Act, also known as the ''Oil Shale, Tar Sands, and Other Strategic Unconventional Fuels Act of 2005,'' Congress declared that oil shale and tar sands (and other unconventional fuels) are strategically important domestic energy resources that should be developed to reduce the nation's growing dependence on oil from politically and economically unstable foreign sources. In addition, Congress declared that both research- and commercial-scale development of oil shale and tar sands should (1) be conducted in an environmentally sound mannermore » using management practices that will minimize potential impacts, (2) occur with an emphasis on sustainability, and (3) benefit the United States while taking into account concerns of the affected states and communities. To support this declaration of policy, Congress directed the Secretary of the Interior to undertake a series of steps, several of which are directly related to the development of a commercial leasing program for oil shale and tar sands. One of these steps was the completion of a programmatic environmental impact statement (PEIS) to analyze the impacts of a commercial leasing program for oil shale and tar sands resources on public lands, with an emphasis on the most geologically prospective lands in Colorado, Utah, and Wyoming. For oil shale, the scope of the PEIS analysis includes public lands within the Green River, Washakie, Uinta, and Piceance Creek Basins. For tar sands, the scope includes Special Tar Sand Areas (STSAs) located in Utah. This paleontological resources overview report was prepared in support of the Oil Shale and Tar Sands Resource Management Plan Amendments to Address Land Use Allocations in Colorado, Utah, and Wyoming and PEIS, and it is intended to be used by Bureau of Land Management (BLM) regional paleontologists and field office staff to support future projectspecific

  16. Tar Management and Recycling in Biomass Gasification and Syngas Purification

    NASA Astrophysics Data System (ADS)

    McCaffrey, Zach

    Removal of tars is critical to the design and operation of biomass gasification systems as most syngas utilization processing equipment (e.g. internal combustion engines, gas turbines, fuel cells, and liquid fuel synthesis reactors) have a low tolerance for tar. Capturing and disposal of tar is expensive due to equipment costs, high hazardous waste disposal costs where direct uses cannot be found, and system energy losses incurred. Water scrubbing is an existing technique commonly used in gasification plants to remove contaminants and tar; however using water as the absorbent is non-ideal as tar compounds have low or no water solubility. Hydrophobic solvents can improve scrubber performance and this study evaluated tar solubility in selected solvents using slip-streams of untreated syngas from a laboratory fluidized bed reactor operated on almond composite feedstock using both air and steam gasification. Tar solubility was compared with Hansen's solubility theory to examine the extent to which the tar removal can be predicted. As collection of tar without utilization leads to a hazardous waste problem, the study investigated the effects of recycling tars back into the gasifier for destruction. Prior to experiments conducted on tar capture and recycle, characterizations of the air and steam gasification of the almond composite mix were made. This work aims to provide a better understanding of tar collection and solvent selection for wet scrubbers, and to provide information for designing improved tar management systems for biomass gasification.

  17. 16 CFR 802.3 - Acquisitions of carbon-based mineral reserves.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... gas, shale or tar sands, or rights to reserves of oil, natural gas, shale or tar sands together with... gas, shale or tar sands, or rights to reserves of oil, natural gas, shale or tar sands and associated... pipeline and pipeline system or processing facility which transports or processes oil and gas after it...

  18. 16 CFR 802.3 - Acquisitions of carbon-based mineral reserves.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... gas, shale or tar sands, or rights to reserves of oil, natural gas, shale or tar sands together with... gas, shale or tar sands, or rights to reserves of oil, natural gas, shale or tar sands and associated... pipeline and pipeline system or processing facility which transports or processes oil and gas after it...

  19. 16 CFR 802.3 - Acquisitions of carbon-based mineral reserves.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... gas, shale or tar sands, or rights to reserves of oil, natural gas, shale or tar sands together with... gas, shale or tar sands, or rights to reserves of oil, natural gas, shale or tar sands and associated... pipeline and pipeline system or processing facility which transports or processes oil and gas after it...

  20. 16 CFR 802.3 - Acquisitions of carbon-based mineral reserves.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... gas, shale or tar sands, or rights to reserves of oil, natural gas, shale or tar sands together with... gas, shale or tar sands, or rights to reserves of oil, natural gas, shale or tar sands and associated... pipeline and pipeline system or processing facility which transports or processes oil and gas after it...

  1. 16 CFR 802.3 - Acquisitions of carbon-based mineral reserves.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... gas, shale or tar sands, or rights to reserves of oil, natural gas, shale or tar sands together with... gas, shale or tar sands, or rights to reserves of oil, natural gas, shale or tar sands and associated... pipeline and pipeline system or processing facility which transports or processes oil and gas after it...

  2. Smokers' knowledge and understanding of advertised tar numbers: health policy implications.

    PubMed

    Cohen, J B

    1996-01-01

    This article examines health policy implications of providing smokers with numerical tar yield information in cigarette advertising. Results of a national probability telephone survey regarding smokers' knowledge and understanding of numerical tar yields and deliveries are reported. Few smokers knew the tar level of their own cigarettes (the exception being smokers of 1- to 5-mg tar cigarettes), and a majority could not correctly judge the relative tar levels of cigarettes. Smokers were unsure whether switching to lower-tar cigarettes would reduce their personal health risks. Many smokers relied on absolute numbers in making trade-offs between number of cigarettes smoked and their tar levels, thus confusion machine-rated tar-yields with actual amounts ingested. The wisdom of the present method of providing tar and nicotine numbers in ads and recommendations for modifying the test protocol are now under discussion. This research indicates that these tar numbers and their implications are poorly understood. The paper recommends revisions in tar ratings to make them more useful and a required statement on cigarette packages to more explicitly relate tar levels to major health risks.

  3. 7 CFR 3201.76 - Asphalt and tar removers.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Asphalt and tar removers. 3201.76 Section 3201.76... Designated Items § 3201.76 Asphalt and tar removers. (a) Definition. Cleaning agents designed to remove asphalt or tar from equipment, roads, or other surfaces. (b) Minimum biobased content. The Federal...

  4. 7 CFR 3201.76 - Asphalt and tar removers.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Asphalt and tar removers. 3201.76 Section 3201.76... Designated Items § 3201.76 Asphalt and tar removers. (a) Definition. Cleaning agents designed to remove asphalt or tar from equipment, roads, or other surfaces. (b) Minimum biobased content. The Federal...

  5. Task 3.9 -- Catalytic tar cracking. Semi-annual report, January 1--June 30, 1995

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Young, B.C.; Timpe, R.C.

    1995-12-31

    Tar produced in the gasification of coal is deleterious to the operation of downstream equipment including fuel cells, gas turbines, hot-gas stream cleanup filters, and pressure swing adsorption systems. Catalytic cracking of tars to smaller hydrocarbons can be an effective means to remove these tars from gas streams and, in the process, generate useful products, e.g., methane gas, which is crucial to the operation of molten carbonate fuel cells. The objectives of this project are to investigate whether gasification tars can be cracked by synthetic nickel-substituted micamontmorillonite, zeolite, or dolomite material; and whether the tars can be cracked selectively bymore » these catalysts to produce a desired liquid and/or gas stream. Results to date are presented in the cited papers.« less

  6. Smokers' knowledge and understanding of advertised tar numbers: health policy implications.

    PubMed Central

    Cohen, J B

    1996-01-01

    OBJECTIVES. This article examines health policy implications of providing smokers with numerical tar yield information in cigarette advertising. METHODS. Results of a national probability telephone survey regarding smokers' knowledge and understanding of numerical tar yields and deliveries are reported. RESULTS. Few smokers knew the tar level of their own cigarettes (the exception being smokers of 1- to 5-mg tar cigarettes), and a majority could not correctly judge the relative tar levels of cigarettes. Smokers were unsure whether switching to lower-tar cigarettes would reduce their personal health risks. Many smokers relied on absolute numbers in making trade-offs between number of cigarettes smoked and their tar levels, thus confusion machine-rated tar-yields with actual amounts ingested. CONCLUSIONS. The wisdom of the present method of providing tar and nicotine numbers in ads and recommendations for modifying the test protocol are now under discussion. This research indicates that these tar numbers and their implications are poorly understood. The paper recommends revisions in tar ratings to make them more useful and a required statement on cigarette packages to more explicitly relate tar levels to major health risks. PMID:8561236

  7. Catalytic Tar Reduction for Assistance in Thermal Conversion of Space Waste for Energy Production

    NASA Technical Reports Server (NTRS)

    Caraccio, Anne Joan; Devor, Robert William; Hintze, Paul E.; Muscatello, Anthony C.; Nur, Mononita

    2014-01-01

    The Trash to Gas (TtG) project investigates technologies for converting waste generated during spaceflight into various resources. One of these technologies was gasification, which employed a downdraft reactor designed and manufactured at NASA's Kennedy Space Center (KSC) for the conversion of simulated space trash to carbon dioxide. The carbon dioxide would then be converted to methane for propulsion and water for life support systems. A minor byproduct of gasification includes large hydrocarbons, also known as tars. Tars are unwanted byproducts that add contamination to the product stream, clog the reactor and cause complications in analysis instrumentation. The objective of this research was to perform reduction studies of a mock tar using select catalysts and choose the most effective for primary treatment within the KSC downdraft gasification reactor. Because the KSC reactor is operated at temperatures below typical gasification reactors, this study evaluates catalyst performance below recommended catalytic operating temperatures. The tar reduction experimentation was observed by passing a model tar vapor stream over the catalysts at similar conditions to that of the KSC reactor. Reduction in tar was determined using gas chromatography. Tar reduction efficiency and catalyst performances were evaluated at different temperatures.

  8. Porous Carbon Nanofibers from Electrospun Biomass Tar/Polyacrylonitrile/Silver Hybrids as Antimicrobial Materials.

    PubMed

    Song, Kunlin; Wu, Qinglin; Zhang, Zhen; Ren, Suxia; Lei, Tingzhou; Negulescu, Ioan I; Zhang, Quanguo

    2015-07-15

    A novel route to fabricate low-cost porous carbon nanofibers (CNFs) using biomass tar, polyacrylonitrile (PAN), and silver nanoparticles has been demonstrated through electrospinning and subsequent stabilization and carbonization processes. The continuous electrospun nanofibers had average diameters ranging from 392 to 903 nm. The addition of biomass tar resulted in increased fiber diameters, reduced thermal stabilities, and slowed cyclization reactions of PAN in the as-spun nanofibers. After stabilization and carbonization, the resultant CNFs showed more uniformly sized and reduced average diameters (226-507 nm) compared to as-spun nanofibers. The CNFs exhibited high specific surface area (>400 m(2)/g) and microporosity, attributed to the combined effects of phase separations of the tar and PAN and thermal decompositions of tar components. These pore characteristics increased the exposures and contacts of silver nanoparticles to the bacteria including Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli, leading to excellent antimicrobial performances of as-spun nanofibers and CNFs. A new strategy is thus provided for utilizing biomass tar as a low-cost precursor to prepare functional CNFs and reduce environmental pollutions associated with direct disposal of tar as an industrial waste.

  9. A comparison of physicochemical methods for the remediation of porous medium systems contaminated with tar

    NASA Astrophysics Data System (ADS)

    Hauswirth, Scott C.; Miller, Cass T.

    2014-10-01

    The remediation of former manufactured gas plant (FMGP) sites contaminated with tar DNAPLs (dense non-aqueous phase liquids) presents a significant challenge. The tars are viscous mixtures of thousands of individual compounds, including known and suspected carcinogens. This work investigates the use of combinations of mobilization, solubilization, and chemical oxidation approaches to remove and degrade tars and tar components in porous medium systems. Column experiments were conducted using several flushing solutions, including an alkaline-polymer (AP) solution containing NaOH and xanthan gum (XG), a surfactant-polymer (SP) solution containing Triton X-100 surfactant (TX100) and XG, an alkaline-surfactant-polymer (ASP) solution containing NaOH, TX100, and XG, and base-activated sodium persulfate both with and without added TX100. The effectiveness of the flushing solutions was assessed based on both removal of polycyclic aromatic hydrocarbon (PAH) mass and on the reduction of dissolved-phase PAH concentrations. SP flushes of 6.6 to 20.9 PV removed over 99% of residual PAH mass and reduced dissolved-phase concentrations by up to two orders of magnitude. ASP flushing efficiently removed 95-96% of residual PAH mass within about 2 PV, and significantly reduced dissolved-phase concentrations of several low molar mass compounds, including naphthalene, acenaphthene, fluorene, and phenanthrene. AP flushing removed a large portion of the residual tar (77%), but was considerably less effective than SP and ASP in terms of the effect on dissolved PAH concentrations. Persulfate was shown to oxidize tar components, primarily those with low molar mass, however, the overall degradation was relatively low (30-50% in columns with low initial tar saturations), and the impact on dissolved-phase concentrations was minimal.

  10. Transverse Aeolian Ridges (TARs) on Mars II: Distributions, orientations, and ages

    NASA Astrophysics Data System (ADS)

    Berman, Daniel C.; Balme, Matthew R.; Rafkin, Scot C. R.; Zimbelman, James R.

    2011-05-01

    Transverse Aeolian Ridges (TARs), 10 m scale, ripple-like aeolian bedforms with simple morphology, are widespread on Mars but it is unknown what role they play in Mars' wider sediment cycle. We present the results of a survey of all Mars Global Surveyor Narrow angle images in a pole-to-pole study area, 45° longitude wide. Following on from the classification scheme and preliminary surveys of Balme et al. (Balme, M.R., Berman, D.C., Bourke, M.C., Zimbelman, J.R. [2008a]. Geomorphology 101, 703-720) and Wilson and Zimbelman (Wilson, S.A., Zimbelman, J.R. [2004]. J. Geophys. Res. 109 (E10). doi: 10.1029/2004JE002247) we searched more than 10,000 images, and found that over 2000 reveal at least 5% areal cover by TARs. The mean TAR areal cover in the study area is about 7% (3% in the northern hemisphere and 11% in the southern hemisphere) but TARs are not homogenously distributed - they are concentrated in the mid-low latitudes and almost absent poleward of 35°N and 55°S. We found no clear correlation between TAR distribution and any of thermal inertia, kilometer-scale roughness, or elevation. We did find that TARs are less common at extremes of elevation. We found that TARs are most common near the equator (especially in the vicinity of Meridiani Planum, in which area they have a distinctive "barchan-like" morphology) and in large southern-hemisphere impact craters. TARs in the equatorial band are usually associated with outcrops of layered terrain or steep slopes, hence their relative absence in the northern hemisphere. TARs in the southern hemisphere are most commonly associated with low albedo, intercrater dune fields. We speculate that the mid-latitude mantling terrain (e.g., Mustard, J.F., Cooper, C.D., Rifkin, M.K. [2001]. Nature 412, 411-414; Kreslavsky, M.A., Head, J.W. [2002]. J. Geophys. Res. 29 (15). doi: 10.1029/2002GL015392) could also play a role in covering TARs or inhibiting saltation. We compared TAR distribution with general circulation model (GCM

  11. Atmospheric Tar Balls: Particles from Biomass and Biofuel Burning

    NASA Technical Reports Server (NTRS)

    Posfai, Mihaly; Gelencser, Andras; Simonics, Renata; Arato, Krisztina; Li, Jia; Hobbs, Peter V.; Buseck, Peter R.

    2004-01-01

    Tar balls are amorphous, carbonaceous spherules that occur in the tropospheric aerosol as a result of biomass and biofuel burning. They form a distinct group of particles with diameters typically between 30 and 500 nm and readily identifiable with electron microscopy. Their lack of a turbostratic microstructure distinguishes them from soot, and their morphology and composition (approximately 90 mol% carbon) renders them distinct from other carbonaceous particles. Tar balls are particularly abundant in slightly aged (minutes to hours old) biomass smoke, indicating that they likely form by gas-to-particle conversion within smoke plumes. The material of tar balls is initially hygroscopic; however, the particles become largely insoluble as a result of free radical polymerization of their organic molecules. Consequently, tar balls are primarily externally mixed with other particle types, and they do not appreciably increase in size during aging. When tar balls coagulate with water-bearing particles, their material may partly dissolve and no longer be recognizable as distinct particles. Tar balls may contain organic compounds that absorb sunlight. They are an important, previously unrecognized type of carbonaceous (organic) atmospheric particle.

  12. Tar, nicotine, and carbon monoxide yields of some Nigerian cigarettes.

    PubMed Central

    Awotedu, A A; Higenbottam, T W; Onadeko, B O

    1983-01-01

    Fourteen cigarette brands manufactured in Nigeria in 1981 were analysed to determine the tar, nicotine, and carbon monoxide yields. Five of the brands belonged to the high and middle to high tar category (greater than 22 mg/cigarette) and nine to the middle tar (17-22 mg/cigarette) category. None of the cigarettes was in the low to middle and low tar (less than 17 mg/cigarette) category. The nicotine and carbon monoxide yields were similar to those of European cigarettes. Tobacco companies need to manufacture low tar cigarettes in the Third World as is the practice in the economically developed parts of the world. PMID:6619721

  13. Bitumen recovery from oil sands using deep eutectic solvent and its aqueous solutions

    NASA Astrophysics Data System (ADS)

    Pulati, Nuerxida

    Oil sands compose a significant proportion of the world's known oil reserves. Oil sands are also known as tar sands and bituminous sands, are complex mixtures of sand, clays, water and bitumen, which is "heavy" and highly viscous oil. The extraction and separation of bitumen from oil sands requires significant amount of energy and large quantities of water and poses several environmental challenges. Bitumen can be successfully separated from oil sands using imidazolium based ionic liquids and nonpolar solvents, however, ionic liquids are expensive and toxic. In this thesis, the ionic liquid alternatives- deep eutectic solvent, were investigated. Oil sands separation can be successfully achieved by using deep eutectic solvents DES (choline chloride and urea) and nonpolar solvent naphtha in different types of oil sands, including Canadian ("water-wet"), Utah ("oil-wet") and low grade Kentucky oil sands. The separation quality depends on oil sands type, including bitumen and fine content, and separation condition, such as solvent ratio, temperature, mixing time and mechanical centrifuge. This separation claims to the DES ability to form ion /charge layering on mineral surface, which results in reduction of adhesion forces between bitumen and minerals and promote their separation. Addition of water to DES can reduce DES viscosity. DES water mixture as a media, oil sands separation can be achieved. However, concentration at about 50 % or higher might be required to obtain a clear separation. And the separation efficiency is oil sands sample dependent. The highest bitumen extraction yield happened at 75% DES-water solution for Utah oil sands samples, and at 50 60% DES-water solutions for Alberta oil sands samples. Force curves were measured using Atomic Force Microscopy new technique, PeakForce Tapping Quantitative Nanomechanical Mapping (PFTQNM). The results demonstrate that, by adding DES, the adhesion force between bitumen and silica and dissipation energy will

  14. VAPOR PRESSURES AND HEATS OF VAPORIZATION OF PRIMARY COAL TARS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eric M. Suuberg; Vahur Oja

    1997-07-01

    This project had as its main focus the determination of vapor pressures of coal pyrolysis tars. It involved performing measurements of these vapor pressures and from them, developing vapor pressure correlations suitable for use in advanced pyrolysis models (those models which explicitly account for mass transport limitations). This report is divided into five main chapters. Each chapter is a relatively stand-alone section. Chapter A reviews the general nature of coal tars and gives a summary of existing vapor pressure correlations for coal tars and model compounds. Chapter B summarizes the main experimental approaches for coal tar preparation and characterization whichmore » have been used throughout the project. Chapter C is concerned with the selection of the model compounds for coal pyrolysis tars and reviews the data available to us on the vapor pressures of high boiling point aromatic compounds. This chapter also deals with the question of identifying factors that govern the vapor pressures of coal tar model materials and their mixtures. Chapter D covers the vapor pressures and heats of vaporization of primary cellulose tars. Chapter E discusses the results of the main focus of this study. In summary, this work provides improved understanding of the volatility of coal and cellulose pyrolysis tars. It has resulted in new experimentally verified vapor pressure correlations for use in pyrolysis models. Further research on this topic should aim at developing general vapor pressure correlations for all coal tars, based on their molecular weight together with certain specific chemical characteristics i.e. hydroxyl group content.« less

  15. Wet scrubbing of biomass producer gas tars using vegetable oil

    NASA Astrophysics Data System (ADS)

    Bhoi, Prakashbhai Ramabhai

    The overall aims of this research study were to generate novel design data and to develop an equilibrium stage-based thermodynamic model of a vegetable oil based wet scrubbing system for the removal of model tar compounds (benzene, toluene and ethylbenzene) found in biomass producer gas. The specific objectives were to design, fabricate and evaluate a vegetable oil based wet scrubbing system and to optimize the design and operating variables; i.e., packed bed height, vegetable oil type, solvent temperature, and solvent flow rate. The experimental wet packed bed scrubbing system includes a liquid distributor specifically designed to distribute a high viscous vegetable oil uniformly and a mixing section, which was designed to generate a desired concentration of tar compounds in a simulated air stream. A method and calibration protocol of gas chromatography/mass spectroscopy was developed to quantify tar compounds. Experimental data were analyzed statistically using analysis of variance (ANOVA) procedure. Statistical analysis showed that both soybean and canola oils are potential solvents, providing comparable removal efficiency of tar compounds. The experimental height equivalent to a theoretical plate (HETP) was determined as 0.11 m for vegetable oil based scrubbing system. Packed bed height and solvent temperature had highly significant effect (p0.05) effect on the removal of model tar compounds. The packing specific constants, Ch and CP,0, for the Billet and Schultes pressure drop correlation were determined as 2.52 and 2.93, respectively. The equilibrium stage based thermodynamic model predicted the removal efficiency of model tar compounds in the range of 1-6%, 1-4% and 1-2% of experimental data for benzene, toluene and ethylbenzene, respectively, for the solvent temperature of 30° C. The NRTL-PR property model and UNIFAC for estimating binary interaction parameters are recommended for modeling absorption of tar compounds in vegetable oils. Bench scale

  16. Ultrasound assisted, thermally activated persulfate oxidation of coal tar DNAPLs.

    PubMed

    Peng, Libin; Wang, Li; Hu, Xingting; Wu, Peihui; Wang, Xueqing; Huang, Chumei; Wang, Xiangyang; Deng, Dayi

    2016-11-15

    The feasibility of ultrasound assisted, thermally activated persulfate for effective oxidation of twenty 2-6 ringed coal tar PAHs in a biphasic tar/water system and a triphasic tar/soil/water system were investigated and established. The results indicate that ultrasonic assistance, persulfate and elevated reaction temperature are all required to achieve effective oxidation of coal tar PAHs, while the heating needed can be provided by ultrasonic induced heating as well. Further kinetic analysis reveals that the oxidation of individual PAH in the biphasic tar/water system follows the first-order kinetics, and individual PAH oxidation rate is primary determined by the mass transfer coefficients, tar/water interfacial areas, the aqueous solubility of individual PAH and its concentration in coal tar. Based on the kinetic analysis and experimental results, the contributions of ultrasound, persulfate and elevated reaction temperature to PAHs oxidation were characterized, and the effects of ultrasonic intensity and oxidant dosage on PAHs oxidation efficiency were investigated. In addition, the results indicate that individual PAH degradability is closely related to its reactivity as well, and the high reactivity of 4-6 ringed PAHs substantially improves their degradability. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Impact of genetic variants on haematopoiesis in patients with thrombocytopenia absent radii (TAR) syndrome.

    PubMed

    Manukjan, Georgi; Bösing, Hendrik; Schmugge, Markus; Strauß, Gabriele; Schulze, Harald

    2017-11-01

    Thrombocytopenia absent radii (TAR) syndrome is clearly defined by the combination of radial aplasia and reduced platelet counts. The genetics of TAR syndrome has recently been resolved and comprises a microdeletion on Chromosome 1 including the RBM8A gene and a single nucleotide polymorphism (SNP) either at the 5' untranslated region (5'UTR) or within the first intron of RBM8A. Although phenotypically readily diagnosed after birth, the genetic determination of particular SNPs in TAR syndrome harbours valuable information to evaluate disease severity and treatment decisions. Here, we present clinical data in a cohort of 38 patients and observed that platelet counts in individuals with 5'UTR SNP are significantly lower compared to patients bearing the SNP in intron 1. Moreover, elevated haemoglobin values could only be assessed in patients with 5'UTR SNP whereas white blood cell count is unaffected, indicating that frequently observed anaemia in TAR patients could also be SNP-dependent whereas leucocytosis does not correlate with genetic background. However, this report on a large cohort provides an overview of important haematological characteristics in TAR patients, facilitating evaluation of the various traits in this disease and indicating the importance of genetic validation for TAR syndrome. © 2017 John Wiley & Sons Ltd.

  18. 77 FR 5833 - Notice of Availability of the Draft Programmatic Environmental Impact Statement for Allocation of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-06

    ... of the Draft Programmatic Environmental Impact Statement for Allocation of Oil Shale and Tar Sands... of Oil Shale and Tar Sands Resources on Lands Administered by the BLM in Colorado, Utah, and Wyoming... preferred method of commenting. Mail: Addressed to: Oil Shale and Tar Sands Resources Draft Programmatic EIS...

  19. Selected constituents in the smokes of U. S. commercial cigaretts: tar, nicotine, carbon monoxide and carbon dioxide

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jenkins, R.A.; Quincy, R.B.; Guerin, M.R.

    One hundred twenty-one brands of United States commercial cigarettes were analyzed for their deliveries of tar, nicotine, carbon monoxide, and carbon dioxide under standard analytical smoking conditions. The sample included both filter and nonfilter cigarettes. Comparisons of carbon monoxide deliveries over the range of observed tar deliveries indicated a very high correlation between CO and tar for filter cigarettes, but nonfilter cigarettes tended to produce much less CO than would have been predicted from their tar deliveries. Comparison of ORNL nicotine values for specific brands with those determined by the Federal Trade Commission yield no statistically significant differences between laboratories.more » 4 figures, 6 tables.« less

  20. 76 FR 21003 - Notice of Intent To Prepare a Programmatic Environmental Impact Statement (EIS) and Possible Land...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-14

    ... Allocation of Oil Shale and Tar Sands Resources on Lands Administered by the Bureau of Land Management in... to prepare a Programmatic EIS for Allocation of Oil Shale and Tar Sands Resources on Lands... following methods: Web site: http://blm.gov/st5c . Mail: BLM Oil Shale and Tar Sands Resources Leasing...

  1. Use of mineral oil Fleet enema for the removal of a large tar burn: a case report.

    PubMed

    Carta, Tricia; Gawaziuk, Justin; Liu, Song; Logsetty, Sarvesh

    2015-03-01

    Extensive hot tar burns are relatively uncommon. Management of these burns provides a significant clinical challenge especially with respect to tar removal involving a large total body surface area (TBSA), without causing further tissue injury. We report a case of an over 40-year old male construction worker who was removing a malfunctioning cap from broken valve. This resulted in tar spraying over the anterior surface of his body including legs, feet, chest, abdomen, arms, face and oral cavity (80% TBSA covered in tar resulting in a 50% TBSA burn injury). Initially, petrolatum-based, double antibiotic ointment was used to remove the tar, based on our previous experience with small tar burns. However, this was time-consuming and ineffective. The tar was easily removed with mineral oil without irritation. In order to meet the demand for quantity of mineral oil, the pharmacy suggested using mineral oil Fleet enema (C.B. Fleet Company, Inc., Lynchburg, Virginia, USA). The squeezable bottle and catheter tip facilitated administration of oil into the patient's construction boots and under clothing that was adhered to the patient's skin. Tar removal requires an effective, non-toxic and non-irritating agent. Mineral oil is such an agent. For patients that may present with a large surface area tar burn, using mineral oil Fleet enema is a viable option that facilitates application into difficult areas. Grant Support: The Firefighters' Burn Fund (Manitoba) supported this project. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

  2. 48 CFR Appendix to Part 1252 - Tar Matrix

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Tar Matrix Appendix to Part 1252 Federal Acquisition Regulations System DEPARTMENT OF TRANSPORTATION CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Pt. 1252, App. Appendix to Part 1252—Tar Matrix ER27DE05.000...

  3. Banded TARs in Iapygia

    NASA Image and Video Library

    2014-09-10

    The tropics of Mars are commonly littered with small bright ripples that were somehow shaped by the wind. NASA Mars Reconnaissance Orbiter might provide a valuable clue to the formation of transverse aeolian ridges TARs elsewhere on Mars.

  4. Coal tar-containing asphalt - resource or hazardous waste?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Andersson-Skold, Y.; Andersson, K.; Lind, B.

    2007-09-30

    Coal tar was used in Sweden for the production of asphalt and for the drenching of stabilization gravel until 1973. The tar has high concentrations of polycyclic aromatic hydrocarbons (PAH), some of which may be strongly carcinogenic. Approximately 20 million tonnes of tar-containing asphalt is present in the public roads in Sweden. Used asphalt from rebuilding can be classified as hazardous waste according to the Swedish Waste Act. The cost of treating the material removed as hazardous waste can be very high due to the large amount that has to be treated, and the total environmental benefit is unclear. Themore » transport of used asphalt to landfill or combustion will affect other environmental targets. The present project, based on three case studies of road projects in Sweden, evaluates the consequences of four scenarios for handling the material: reuse, landfill, biological treatment, and incineration. The results show that reuse of the coal tar-containing materials in new road construction is the most favorable alternative in terms of cost, material use, land use, energy consumption, and air emissions.« less

  5. Transformation-associated recombination (TAR) cloning for genomics studies and synthetic biology

    PubMed Central

    Kouprina, Natalay; Larionov, Vladimir

    2016-01-01

    Transformation-associated recombination (TAR) cloning represents a unique tool for isolation and manipulation of large DNA molecules. The technique exploits a high level of homologous recombination in the yeast Sacharomyces cerevisiae. So far, TAR cloning is the only method available to selectively recover chromosomal segments up to 300 kb in length from complex and simple genomes. In addition, TAR cloning allows the assembly and cloning of entire microbe genomes up to several Mb as well as engineering of large metabolic pathways. In this review, we summarize applications of TAR cloning for functional/structural genomics and synthetic biology. PMID:27116033

  6. Sampling of tar from sewage sludge gasification using solid phase adsorption.

    PubMed

    Ortiz González, Isabel; Pérez Pastor, Rosa Ma; Sánchez Hervás, José Ma

    2012-06-01

    Sewage sludge is a residue from wastewater treatment plants which is considered to be harmful to the environment and all living organisms. Gasification technology is a potential source of renewable energy that converts the sewage sludge into gases that can be used to generate energy or as raw material in chemical synthesis processes. But tar produced during gasification is one of the problems for the implementation of the gasification technology. Tar can condense on pipes and filters and may cause blockage and corrosion in the engines and turbines. Consequently, to minimize tar content in syngas, the ability to quantify tar levels in process streams is essential. The aim of this work was to develop an accurate tar sampling and analysis methodology using solid phase adsorption (SPA) in order to apply it to tar sampling from sewage sludge gasification gases. Four types of commercial SPA cartridges have been tested to determine the most suitable one for the sampling of individual tar compounds in such streams. Afterwards, the capacity, breakthrough volume and sample stability of the Supelclean™ ENVI-Carb/NH(2), which is identified as the most suitable, have been determined. Basically, no significant influences from water, H(2)S or NH(3) were detected. The cartridge was used in sampling real samples, and comparable results were obtained with the present and traditional methods.

  7. Probing interaction of a fluorescent ligand with HIV TAR RNA

    NASA Astrophysics Data System (ADS)

    Qi, Liang; Zhang, Jing; He, Tian; Huo, Yuan; Zhang, Zhi-Qi

    2017-02-01

    Trans-activator of Transcription (Tat) antagonists could block the interaction between Tat protein and its target, trans-activation responsive region (TAR) RNA, to inhibit Tat function and prevent human immunodeficiency virus type 1 (HIV-1) replication. For the first time, a small fluorescence ligand, ICR 191, was found to interact with TAR RNA at the Tat binding site and compete with Tat. It was also observed that the fluorescence of ICR 191 could be quenched when binding to TAR RNA and recovered when discharged via competition with Tat peptide or a well-known Tat inhibitor, neomycin B. The binding parameters of ICR 191 to TAR RNA were determined through theoretical calculations. Mass spectrometry, circular dichroism and molecular docking were used to further confirm the interaction of ICR 191 with TAR RNA. Inspired by these discoveries, a primary fluorescence model for the discovery of Tat antagonists was built using ICR 191 as a fluorescence indicator and the feasibility of this model was evaluated. This ligand-RNA interaction could provide a new strategy for research aimed at discovering Tat antagonists.

  8. Thermocatalytic treatment of biomass tar model compounds via radio frequency.

    PubMed

    Anis, Samsudin; Zainal, Z A; Bakar, M Z A

    2013-05-01

    A new effective RF tar thermocatalytic treatment process with low energy intensive has been proposed to remove tar from biomass gasification. Toluene and naphthalene as biomass tar model compounds were removed via both thermal and catalytic treatment over a wide temperature range from 850 °C to 1200 °C and 450 °C to 900 °C, respectively at residence time of 0-0.7 s. Thermal characteristics of the new technique are also described in this paper. This study clearly clarified that toluene was much easier to be removed than naphthalene. Soot was found as the final product of thermal treatment of the tar model and completely removed during catalytic treatment. Radical reactions generated by RF non-thermal effect improve the tar removal. The study showed that Y-zeolite has better catalytic activity compared to dolomite on toluene and naphthalene removal due to its acidic nature and large surface area, even at lower reaction temperature of about 550 °C. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Assessment of tar pollution on the United Arab emirates beaches

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Abu-Hilal, A.H.; Khordagui, H.K.

    1993-01-01

    In light of the inadequate information concerning stranded tar on the southwest beaches of the Arabian Gulf and the Gulf of Oman, particularly following the massive oil releases during the Gulf War, the present investigation was designed to provide reference-integrated information on the nature, location, and levels of stranded tar balls on the beaches of the United Arab Emirates (UAE). The recorded levels appeared to be higher than expected or previously reported. The tar distribution pattern, in addition to the degree of weathering, indicates that the massive oil release during the Gulf War did not reach the UAE shorelines. Themore » highest reported levels of stranded tar ever recorded in the Arabian Gulf at Jabal Dhannah apparently originated from oil spills and tankers' ballast water at the main oil terminal at the Al-Ruwaiss oil refinery some 10 km to the east. The surprising, relatively high levels of stranded tar on the beaches of the Gulf of Oman were solely attributed to the heavy navigation traffic close to the shorelines. 19 refs., 2 figs., 3 tabs.« less

  10. Treating tar sands formations with dolomite

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vinegar, Harold J.; Karanikas, John Michael

    A method for treating a karsted formation containing heavy hydrocarbons and dolomite includes providing heat to at least part of one or more karsted layers in the formation from one or more heaters located in the karsted layers. A temperature in at least one of the karsted layers is allowed to reach a decomposition temperature of dolomite in the formation. The dolomite is allowed to decompose and at least some hydrocarbons are produced from at least one of the karsted layers of the formation.

  11. Potential contributions of asphalt and coal tar to black carbon quantification in urban dust, soils, and sediments

    USGS Publications Warehouse

    Yang, Y.; Mahler, B.J.; Van Metre, P.C.; Ligouis, B.; Werth, C.J.

    2010-01-01

    Measurements of black carbon (BC) using either chemical or thermal oxidation methods are generally thought to indicate the amount of char and/or soot present in a sample. In urban environments, however, asphalt and coal-tar particles worn from pavement are ubiquitous and, because of their pyrogenic origin, could contribute to measurements of BC. Here we explored the effect of the presence of asphalt and coal-tar particles on the quantification of BC in a range of urban environmental sample types, and evaluated biases in the different methods used for quantifying BC. Samples evaluated were pavement dust, residential and commercial area soils, lake sediments from a small urban watershed, and reference materials of asphalt and coal tar. Total BC was quantified using chemical treatment through acid dichromate (Cr2O7) oxidation and chemo-thermal oxidation at 375??C (CTO-375). BC species, including soot and char/charcoal, asphalt, and coal tar, were quantified with organic petrographic analysis. Comparison of results by the two oxidation methods and organic petrography indicates that both coal tar and asphalt contribute to BC quantified by Cr2O7 oxidation, and that coal tar contributes to BC quantified by CTO-375. These results are supported by treatment of asphalt and coal-tar reference samples with Cr2O7 oxidation and CTO-375. The reference asphalt is resistant to Cr2O7 oxidation but not to CTO-375, and the reference coal tar is resistant to both Cr2O7 oxidation and CTO-375. These results indicate that coal tar and/or asphalt can contribute to BC measurements in samples from urban areas using Cr2O7 oxidation or CTO-375, and caution is advised when interpreting BC measurements made with these methods. ?? 2010 Elsevier Ltd.

  12. Industrial sand and gravel

    USGS Publications Warehouse

    Dolley, T.P.

    2012-01-01

    Domestic production of industrial sand and gravel in 2011 was about 30 Mt (33 million st), increasing slightly compared with 2010. Some important end uses for industrial sand and gravel include abrasives, filtration, foundry, glassmaking, hydraulic fracturing sand (frac sand) and silicon metal applications.

  13. Tar Production from Biomass Pyrolysis in a Fluidized Bed Reactor: A Novel Turbulent Multiphase Flow Formulation

    NASA Technical Reports Server (NTRS)

    Bellan, J.; Lathouwers, D.

    2000-01-01

    A novel multiphase flow model is presented for describing the pyrolysis of biomass in a 'bubbling' fluidized bed reactor. The mixture of biomass and sand in a gaseous flow is conceptualized as a particulate phase composed of two classes interacting with the carrier gaseous flow. The solid biomass is composed of three initial species: cellulose, hemicellulose and lignin. From each of these initial species, two new solid species originate during pyrolysis: an 'active' species and a char, thus totaling seven solid-biomass species. The gas phase is composed of the original carrier gas (steam), tar and gas; the last two species originate from the volumetric pyrolysis reaction. The conservation equations are derived from the Boltzmann equations through ensemble averaging. Stresses in the gaseous phase are the sum of the Newtonian and Reynolds (turbulent) contributions. The particulate phase stresses are the sum of collisional and Reynolds contributions. Heat transfer between phases, and heat transfer between classes in the particulate phase is modeled, the last resulting from collisions between sand and biomass. Closure of the equations must be performed by modeling the Reynolds stresses for both phases. The results of a simplified version (first step) of the model are presented.

  14. Thermodynamic analysis of tar reforming through auto-thermal reforming process

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nurhadi, N., E-mail: nurhadi@tekmira.esdm.go.id; Diniyati, Dahlia; Efendi, M. Ade Andriansyah

    2015-12-29

    Fixed bed gasification is a simple and suitable technology for small scale power generation. One of the disadvantages of this technology is producing tar. So far, tar is not utilized yet and being waste that should be treated into a more useful product. This paper presents a thermodynamic analysis of tar conversion into gas producer through non-catalytic auto-thermal reforming technology. Tar was converted into components, C, H, O, N and S, and then reacted with oxidant such as mixture of air or pure oxygen. Thus, this reaction occurred auto-thermally and reached chemical equilibrium. The sensitivity analysis resulted that the mostmore » promising process performance occurred at flow rate of air was reached 43% of stoichiometry while temperature of process is 1100°C, the addition of pure oxygen is 40% and preheating of oxidant flow is 250°C. The yield of the most promising process performance between 11.15-11.17 kmol/h and cold gas efficiency was between 73.8-73.9%.The results of this study indicated that thermodynamically the conversion of tar into producer gas through non-catalytic auto-thermal reformingis more promising.« less

  15. Industrial sand and gravel

    USGS Publications Warehouse

    Dolley, T.P.

    2013-01-01

    Domestic production of industrial sand and gravel in 2012 was about 49.5 Mt (55 million st), increasing 13 percent compared with that of 2011. Some important end uses for industrial sand and gravel include abrasives, filtration, foundry, glassmaking, hydraulic fracturing sand (frac sand) and silicon metal applications.

  16. Deciphering structure-activity relationships in a series of Tat/TAR inhibitors.

    PubMed

    Pascale, Lise; González, Alejandro López; Di Giorgio, Audrey; Gaysinski, Marc; Teixido Closa, Jordi; Tejedor, Roger Estrada; Azoulay, Stéphane; Patino, Nadia

    2016-11-01

    A series of pentameric "Polyamide Amino Acids" (PAAs) compounds derived from the same trimeric precursor have been synthesized and investigated as HIV TAR RNA ligands, in the absence and in the presence of a Tat fragment. All PAAs bind TAR with similar sub-micromolar affinities but their ability to compete efficiently with the Tat fragment strongly differs, IC50 ranging from 35 nM to >2 μM. While NMR and CD studies reveal that all PAA interact with TAR at the same site and induce globally the same RNA conformational change upon binding, a comparative thermodynamic study of PAA/TAR equilibria highlights distinct TAR binding modes for Tat competitor and non-competitor PAAs. This led us to suggest two distinct interaction modes that have been further validated by molecular modeling studies. While the binding of Tat competitor PAAs induces a contraction at the TAR bulge region, the binding of non-competitor ones widens it. This could account for the distinct PAA ability to compete with Tat fragment. Our work illustrates how comparative thermodynamic studies of a series of RNA ligands of same chemical family are of value for understanding their binding modes and for rationalizing structure-activity relationships.

  17. Microbial Diversity in Natural Asphalts of the Rancho La Brea Tar Pits▿

    PubMed Central

    Kim, Jong-Shik; Crowley, David E.

    2007-01-01

    Bacteria commonly inhabit subsurface oil reservoirs, but almost nothing is known yet about microorganisms that live in naturally occurring terrestrial oil seeps and natural asphalts that are comprised of highly recalcitrant petroleum hydrocarbons. Here we report the first survey of microbial diversity in ca. 28,000-year-old samples of natural asphalts from the Rancho La Brea Tar Pits in Los Angeles, CA. Microbiological studies included analyses of 16S rRNA gene sequences and DNA encoding aromatic ring-hydroxylating dioxygenases from two tar pits differing in chemical composition. Our results revealed a wide range of phylogenetic groups within the Archaea and Bacteria domains, in which individual taxonomic clusters were comprised of sets of closely related species within novel genera and families. Fluorescent staining of asphalt-soil particles using phylogenetic probes for Archaea, Bacteria, and Pseudomonas showed coexistence of mixed microbial communities at high cell densities. Genes encoding dioxygenases included three novel clusters of enzymes. The discovery of life in the tar pits provides an avenue for further studies of the evolution of enzymes and catabolic pathways for bacteria that have been exposed to complex hydrocarbons for millennia. These bacteria also should have application for industrial microbiology and bioremediation. PMID:17416692

  18. Aviation Turbine Fuels from Tar Sands Bitumen and Heavy Oils. Part 3. Laboratory Sample Production.

    DTIC Science & Technology

    1987-12-01

    FILD7 ar Sands, Heavy Ois Jet Fue - - - etF IE L D G R O U P S U B -G R O U P , u e -. IT - 3 seC m ) A s h l GROUP SB-RP Fue-i-T-33-A Reduced Crude...connec- tion with processes for heavy oil cracking and related catalysts. * program which allowed processing of bitumen stocks . The overall process flow

  19. DeepMirTar: a deep-learning approach for predicting human miRNA targets.

    PubMed

    Wen, Ming; Cong, Peisheng; Zhang, Zhimin; Lu, Hongmei; Li, Tonghua

    2018-06-01

    MicroRNAs (miRNAs) are small noncoding RNAs that function in RNA silencing and post-transcriptional regulation of gene expression by targeting messenger RNAs (mRNAs). Because the underlying mechanisms associated with miRNA binding to mRNA are not fully understood, a major challenge of miRNA studies involves the identification of miRNA-target sites on mRNA. In silico prediction of miRNA-target sites can expedite costly and time-consuming experimental work by providing the most promising miRNA-target-site candidates. In this study, we reported the design and implementation of DeepMirTar, a deep-learning-based approach for accurately predicting human miRNA targets at the site level. The predicted miRNA-target sites are those having canonical or non-canonical seed, and features, including high-level expert-designed, low-level expert-designed, and raw-data-level, were used to represent the miRNA-target site. Comparison with other state-of-the-art machine-learning methods and existing miRNA-target-prediction tools indicated that DeepMirTar improved overall predictive performance. DeepMirTar is freely available at https://github.com/Bjoux2/DeepMirTar_SdA. lith@tongji.edu.cn, hongmeilu@csu.edu.cn. Supplementary data are available at Bioinformatics online.

  20. Effect of water addition in a microwave assisted thermal cracking of biomass tar gasification

    NASA Astrophysics Data System (ADS)

    Warsita, A.; Surya, I.

    2018-02-01

    Producer gas from biomass gasification is plagued by the presence of tar which causes pipe blockages. Thermal and catalytic treatments in a microwave reactor have been shown to be effective methods for removing tar from producer gas. A question arises as to the possibility of enhancing the removal mechanism by adding water into the reactor. Thermal treatment with a various amount of water was added at temperatures in the range of 800-1200°C. The tar removal efficiency obtained 96.32% at the optimum temperature of 1200°C at the water to tar ratio (W/T) of 0.3. This study shows that the removal of tar by microwave irradiation with water addition is a significant and effective method in tar cracking.

  1. The TAR effect: when the ones who dislike become the ones who are disliked.

    PubMed

    Gawronski, Bertram; Walther, Eva

    2008-09-01

    Four studies tested whether a source's evaluations of other individuals can recursively transfer to the source, such that people who like others acquire a positive valence, whereas people who dislike others acquire a negative valence (Transfer of Attitudes Recursively; TAR). Experiment 1 provides first evidence for TAR effects, showing recursive transfers of evaluations regardless of whether participants did or did not have prior knowledge about the (dis)liking source. Experiment 2 shows that previously but not subsequently acquired knowledge about targets that were (dis)liked by a source overrode TAR effects in a manner consistent with cognitive balance. Finally, Experiments 3 and 4 demonstrate that TAR effects are mediated by higher order propositional inferences (in contrast to lower order associative processes), in that TAR effects on implicit attitude measures were fully mediated by TAR effects on explicit attitude measures. Commonalities and differences between the TAR effect and previously established phenomena are discussed.

  2. Coal-tar based pavement sealant toxicity to freshwater macroinvertebrates.

    PubMed

    Bryer, Pamela J; Scoggins, Mateo; McClintock, Nancy L

    2010-05-01

    Non-point-source pollution is a major source of ecological impairment in urban stream systems. Recent work suggests that coal-tar pavement sealants, used extensively to protect parking areas, may be contributing a large portion of the polycyclic aromatic hydrocarbon (PAH) loading seen in urban stream sediments. The hypothesis that dried coal-tar pavement sealant flake could alter the macroinvertebrate communities native to streams in Austin, TX was tested using a controlled outdoor laboratory type approach. The treatment groups were: control, low, medium, and high with total PAH concentrations (TPAH = sum of 16 EPA priority pollutant PAHs) of 0.1, 7.5, 18.4, & 300 mg/kg respectively. The low, medium, and high treatments were created via the addition of dried coal-tar pavement sealant to a sterile soil. At the start of the 24-day exposure, sediment from a minimally impacted local reference site containing a community of live sediment-dwelling benthic macroinvertebrates was added to each replicate. An exposure-dependent response was found for several stream health measures and for several individual taxa. There were community differences in abundance (P = 0.0004) and richness (P < 0.0001) between treatments in addition to specific taxa responses, displaying a clear negative relationship with the amount of coal-tar sealant flake. These results support the hypothesis that coal-tar pavement sealants contain bioavailable PAHs that may harm aquatic environments. Copyright 2009 Elsevier Ltd. All rights reserved.

  3. Role of TAR RNA splicing in translational regulation of simian immunodeficiency virus from rhesus macaques.

    PubMed Central

    Viglianti, G A; Rubinstein, E P; Graves, K L

    1992-01-01

    The untranslated leader sequences of rhesus macaque simian immunodeficiency virus mRNAs form a stable secondary structure, TAR. This structure can be modified by RNA splicing. In this study, the role of TAR splicing in virus replication was investigated. The proportion of viral RNAs containing a spliced TAR structure is high early after infection and decreases at later times. Moreover, proviruses containing mutations which prevent TAR splicing are significantly delayed in replication. These mutant viruses require approximately 20 days to achieve half-maximal virus production, in contrast to wild-type viruses, which require approximately 8 days. We attribute this delay to the inefficient translation of unspliced-TAR-containing mRNAs. The molecular basis for this translational effect was examined in in vitro assays. We found that spliced-TAR-containing mRNAs were translated up to 8.5 times more efficiently than were similar mRNAs containing an unspliced TAR leader. Furthermore, these spliced-TAR-containing mRNAs were more efficiently associated with ribosomes. We postulate that the level of TAR splicing provides a balance for the optimal expression of both viral proteins and genomic RNA and therefore ultimately controls the production of infectious virions. Images PMID:1629957

  4. Selected constituents in the smoke of domestic low tar cigarettes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Griest, W. H.; Quincy, R. B.; Guerin, M. R.

    Thirty-two brands of domestic commercial low tar and nicotine cigarettes were analyzed for their production of tar, nicotine, nitrogen oxides (as nitric oxide), hydrogen cyanide, acrolein, carbon monoxide and carbon dioxide under standard analytical smoking conditions. Results are compared with published data for certain brands.

  5. The contribution of low tar cigarettes to environmental tobacco smoke

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chortyk, O.T.; Schlotzhauer, W.S.

    A series of low tar cigarettes (LTC) were smoked and the quantities of condensable mainstream (inhaled) and sidestream (between puffs) smoke compounds were determined and compared to those produced by a high tar, nonfilter cigarette. It was found that the LTC produced large quantities of sidestream smoke condensates, about equal to the high tar cigarette, and contained very high levels of toxic or cocarcinogenic phenols. On an equal weight basis, the LTC emitted more of these hazardous compounds into sidestream and environmental tobacco smoke. Higher smoke yields of a flavor additive and a sugar degradation product indicated addition of suchmore » compounds during the manufacture of LTC. It was concluded that, compared to a high tar cigarette, smoking LTC may be better for the smoker, but not for the nearby nonsmoker. Information should be developed to allow smokers to choose LTC that produce lower levels of hazardous compounds in their environmentally emitted sidestream smoke.« less

  6. 21 CFR 740.18 - Coal tar hair dyes posing a risk of cancer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 7 2012-04-01 2012-04-01 false Coal tar hair dyes posing a risk of cancer. 740.18... (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS Warning Statements § 740.18 Coal tar hair dyes... coal tar hair dye containing any ingredient listed in paragraph (b) of this section shall bear, in...

  7. TAR SANDS LEACHATE STUDY

    EPA Science Inventory

    An inhouse research project was conducted by the EPA's Industrial Environmental Research Laboratory (IERL) at the T&E Facility in Cincinnati, Ohio, to provide information concerning the potential for release of contaminants to groundwater from in-situ and above-ground processed t...

  8. Understanding the stability of pyrolysis tars from biomass in a view point of free radicals.

    PubMed

    He, Wenjing; Liu, Qingya; Shi, Lei; Liu, Zhenyu; Ci, Donghui; Lievens, Caroline; Guo, Xiaofen; Liu, Muxin

    2014-03-01

    Fast pyrolysis of biomass has attracted increasing attention worldwide to produce bio-tars that can be upgraded into liquid fuels and chemicals. However, the bio-tars are usually poor in quality and stability and are difficult to be upgraded. To better understand the nature of the bio-tars, this work reveals radical concentration of tars derived from pyrolysis of two kinds of biomass. The tars were obtained by condensing the pyrolysis volatiles in 3s. It shows that the tars contain large amounts of radicals, at a level of 10(16)spins/g, and are able to generate more radicals at temperatures of 573K or higher, reaching a level of 10(19)spins/g at 673K in less than 30min. The radical generation in the tar samples is attributed to the formation of THF insoluble matters (coke), which also contain radicals. The radical concentrations of the aqueous liquids obtained in pyrolysis are also studied. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Relationship between cigarette format and mouth-level exposure to tar and nicotine in smokers of Russian king-size cigarettes.

    PubMed

    Ashley, Madeleine; Dixon, Mike; Prasad, Krishna

    2014-10-01

    Differences in length and circumference of cigarettes may influence smoker behaviour and exposure to smoke constituents. Superslim king-size (KSSS) cigarettes (17mm circumference versus 25mm circumference of conventional king-size [KS] cigarettes), have gained popularity in several countries, including Russia. Some smoke constituents are lower in machine-smoked KSSS versus KS cigarettes, but few data exist on actual exposure in smokers. We investigated mouth-level exposure (MLE) to tar and nicotine in Russian smokers of KSSS versus KS cigarettes and measured smoke constituents under machine-smoking conditions. MLE to tar was similar for smokers of 1mg ISO tar yield products, but lower for smokers of 4mg and 7mg KSSS versus KS cigarettes. MLE to nicotine was lower in smokers of 4mg KSSS versus KS cigarettes, but not for other tar bands. No gender differences were observed for nicotine or tar MLE. Under International Organization for Standardization, Health Canada Intense and Massachusetts regimes, KSSS cigarettes tended to yield less carbon monoxide, acetaldehyde, nitric oxide, acrylonitrile, benzene, 1,3-butadiene and tobacco-specific nitrosamines, but more formaldehyde, than KS cigarettes. In summary, differences in MLE were observed between cigarette formats, but not systematically across pack tar bands. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  10. Coal-tar-based pavement sealants—a potent source of PAHs

    USGS Publications Warehouse

    Mahler, Barbara J.; Van Metre, Peter C.

    2017-01-01

    P avement sealants are applied to the asphalt pavement of many parking lots, driveways, and even playgrounds in North America (Figure 1), where, when first applied, they render the pavement glossy black and looking like new. Sealant products used commercially in the central, eastern, and northern United States typically are coal-tarbased, whereas those used in the western United States typically are asphalt-based. Although the products look similar, they are chemically different. Coal-tarbased pavement sealants typically are 25-35 percent (by weight) coal tar or coal-tar pitch, materials that are known human carcinogens and that contain high concentrations of polycyclic aromatic hydrocarbons (PAHs) and related chemicals (unless otherwise noted, all Figure 1. Pavement sealant is commonly used to seal parking lots, playgrounds, and driveways throughout the United States. Sealants used in the central, northern, eastern, and southern United States typically contain coal tar or coal-tar pitch, both of which are known human carcinogens. Photos by the U.S. Geological Survey. data in this article are from Mahler et al. 2012 and references therein).

  11. Acid Tar Lagoons: Management and Recovery

    NASA Astrophysics Data System (ADS)

    Bohers, Anna; Hroncová, Emília; Ladomerský, Juraj

    2017-04-01

    This contribution presents the issue with possibility of definitive removal of dangerous environmental burden in Slovakia - serious historical problem of two acid tar lagoons. In relation to their removal, no technology has been found so far - technologically and economically suitable, what caused problems with its management. Locality Predajná is well known in Slovakia by its character of contrasts: it is situated in the picturesque landscape of National Park buffer zone of Nízke Tatry, on the other site it is contaminated by 229 211m3 of acid tar with its characteristics of toxicity, carcinogenicity, teratogenicity, mutagenicity and toxicity especially for animals and plants. Acid tar in two landfills with depth of 1m in case of the first lagoon and 9,5m in case of the second lagoon is a waste product derived from operation of Petrochema Dubová - refinery and petrochemical plant whose activity was to process the crude oil through processes of sulfonation and adsorption technology for producing lubricating and special oils, synthetic detergents and special white oils for cosmetic and medical purposes. A part of acid tar was incinerated in two incineration plats. Concentration of SO2 in combustion gases was too high and it was not possible to decrease it under the value of 2000 mg.mn-3 [LADOMERSKÝ, J. - SAMEŠOVÁ, D.: Reduction in sulfur dioxide emissions waste gases of incineration plant. Acta facultatis ecologiae. 1999, p. 217-223]. That is why it was necessary to put them out of operation. Later, because of public opposition it was not possible to build a new incineration plat corresponding to the state of the art. Even though actual Slovak and European legislative for protection of environment against such impacts, neither of tried methods - bio or non-biologic treatment methods - was proved as suitable for processing or for recovery in the reason of different factors admission: i.e. strong aggressivity, difficulty with handling because of its sludgy and

  12. Estimating tar and nicotine exposure: human smoking versus machine generated smoke yields.

    PubMed

    St Charles, F K; Kabbani, A A; Borgerding, M F

    2010-02-01

    Determine human smoked (HS) cigarette yields of tar and nicotine for smokers using their own brand in their everyday environment. A robust, filter analysis method was used to estimate the tar and nicotine yields for 784 subjects. Seventeen brands were chosen to represent a wide range of styles: 85 and 100 mm lengths; menthol and non-menthol; 17, 23, and 25 mm circumference; with tar yields [Federal Trade Commission (FTC) method] ranging from 1 to 18 mg. Tar bands chosen corresponded to yields of 1-3 mg, 4-6 mg, 7-12 mg, and 13+ mg. A significant difference (p<0.0001) in HS yields of tar and nicotine between tar bands was found. Machine-smoked yields were reasonable predictors of the HS yields for groups of subjects, but the relationship was neither exact nor linear. Neither the FTC, the Massachusetts (MA) nor the Canadian Intensive (CI) machine-smoking methods accurately reflect the HS yields across all brands. The FTC method was closest for the 7-12 mg and 13+ mg products and the MA method was closest for the 1-3mg products. The HS yields for the 4-6 mg products were approximately midway between the FTC and the MA yields. HS nicotine yields corresponded well with published urinary and plasma nicotine biomarker studies. 2009 Elsevier Inc. All rights reserved.

  13. 29 CFR 1926.1102 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 8 2014-07-01 2014-07-01 false Coal tar pitch volatiles; interpretation of term. 1926.1102 Section 1926.1102 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH... Hazardous Substances § 1926.1102 Coal tar pitch volatiles; interpretation of term. Note: The requirements...

  14. 29 CFR 1926.1102 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 8 2011-07-01 2011-07-01 false Coal tar pitch volatiles; interpretation of term. 1926.1102 Section 1926.1102 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH... Hazardous Substances § 1926.1102 Coal tar pitch volatiles; interpretation of term. Note: The requirements...

  15. 29 CFR 1926.1102 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 8 2012-07-01 2012-07-01 false Coal tar pitch volatiles; interpretation of term. 1926.1102 Section 1926.1102 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH... Hazardous Substances § 1926.1102 Coal tar pitch volatiles; interpretation of term. Note: The requirements...

  16. 29 CFR 1926.1102 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Coal tar pitch volatiles; interpretation of term. 1926.1102 Section 1926.1102 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH... Hazardous Substances § 1926.1102 Coal tar pitch volatiles; interpretation of term. Note: The requirements...

  17. Human immunodeficiency virus type 1 LTR TATA and TAR region sequences required for transcriptional regulation.

    PubMed Central

    Garcia, J A; Harrich, D; Soultanakis, E; Wu, F; Mitsuyasu, R; Gaynor, R B

    1989-01-01

    The human immunodeficiency virus (HIV) type 1 LTR is regulated at the transcriptional level by both cellular and viral proteins. Using HeLa cell extracts, multiple regions of the HIV LTR were found to serve as binding sites for cellular proteins. An untranslated region binding protein UBP-1 has been purified and fractions containing this protein bind to both the TAR and TATA regions. To investigate the role of cellular proteins binding to both the TATA and TAR regions and their potential interaction with other HIV DNA binding proteins, oligonucleotide-directed mutagenesis of both these regions was performed followed by DNase I footprinting and transient expression assays. In the TATA region, two direct repeats TC/AAGC/AT/AGCTGC surround the TATA sequence. Mutagenesis of both of these direct repeats or of the TATA sequence interrupted binding over the TATA region on the coding strand, but only a mutation of the TATA sequence affected in vivo assays for tat-activation. In addition to TAR serving as the site of binding of cellular proteins, RNA transcribed from TAR is capable of forming a stable stem-loop structure. To determine the relative importance of DNA binding proteins as compared to secondary structure, oligonucleotide-directed mutations in the TAR region were studied. Local mutations that disrupted either the stem or loop structure were defective in gene expression. However, compensatory mutations which restored base pairing in the stem resulted in complete tat-activation. This indicated a significant role for the stem-loop structure in HIV gene expression. To determine the role of TAR binding proteins, mutations were constructed which extensively changed the primary structure of the TAR region, yet left stem base pairing, stem energy and the loop sequence intact. These mutations resulted in decreased protein binding to TAR DNA and defects in tat-activation, and revealed factor binding specifically to the loop DNA sequence. Further mutagenesis which inverted

  18. Microwave-induced cracking of pyrolytic tars coupled to microwave pyrolysis for syngas production.

    PubMed

    Beneroso, D; Bermúdez, J M; Montes-Morán, M A; Arenillas, A; Menéndez, J A

    2016-10-01

    Herein a new process is proposed to produce a syngas-rich gas fraction (>80vol% H2+CO) from biowaste based on microwave heating within two differentiated steps in order to avoid tars production. The first step consists of the microwave pyrolysis of biowaste induced by a char-based susceptor at 400-800°C; tars, char and syngas-rich gas fractions being produced. The tars are then fed into the second step where a portion of the char from the first step is used as a bed material in a 0.3:1wt% ratio. This bed is heated up by microwaves up to 800°C, allowing thermal cracking of tars and additional syngas (>90vol% H2+CO) being then produced. This new concept arises as an alternative technology to the gasification of biowastes for producing syngas with no need for catalysts or gasifying reagents to minimise tars production. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Relation Between PAHs and Coal-Tar-Based Pavement Sealant in Urban Environments (Invited)

    NASA Astrophysics Data System (ADS)

    Mahler, B. J.; van Metre, P. C.

    2010-12-01

    Since 2003, coal-tar-based sealant products have come under increased scrutiny as a source of PAHs in urban environments. Sealant (or sealcoat) is the black, shiny substance often applied to asphalt pavement, in particular parking lots and driveways, for esthetic and maintenance purposes. Coal-tar-based sealant, one of the two primary pavement sealant types on the market, typically is 20-35 percent coal-tar pitch, a known carcinogen that is more than 50 percent polycyclic aromatic hydrocarbons (PAHs). The PAH content of the coal-tar-based sealant product is about 1,000 times that of a similar, asphalt-based product, on average. This difference is reflected in regional differences in sealant use and PAH concentrations in pavement dust. In the central and eastern U.S., where the coal-tar-based formulation is prevalent, ΣPAH in mobile particles from sealed pavement have been shown to be about 1,000 times higher than in the western U.S., where the asphalt-based formulation is prevalent (the median ΣPAH concentrations are 2,200 mg/kg in the central and eastern U.S. and 2.1 mg/kg in the western U.S.). Source apportionment modeling indicates that, in the central and eastern U.S., particles from sealed pavement are contributing the majority of the PAHs in recently deposited (post-1990) lake sediment, with implications for ecological health, and that coal-tar-based sealant is the primary cause of upward trends in PAHs in U.S. urban lakes. From the standpoint of human health, research indicates that mobile particles from parking lots with coal-tar-based sealant are tracked indoors, resulting in elevated PAH concentrations in house dust. Coal-tar-based sealcoat being applied to an asphalt parking lot at the University of Texas Pickle Research Center.

  20. 29 CFR 1915.1002 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 7 2014-07-01 2014-07-01 false Coal tar pitch volatiles; interpretation of term. 1915.1002 Section 1915.1002 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH... Toxic and Hazardous Substances § 1915.1002 Coal tar pitch volatiles; interpretation of term. Note: The...

  1. 29 CFR 1915.1002 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 7 2011-07-01 2011-07-01 false Coal tar pitch volatiles; interpretation of term. 1915.1002 Section 1915.1002 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH... Toxic and Hazardous Substances § 1915.1002 Coal tar pitch volatiles; interpretation of term. Note: The...

  2. 29 CFR 1915.1002 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 7 2013-07-01 2013-07-01 false Coal tar pitch volatiles; interpretation of term. 1915.1002 Section 1915.1002 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH... Toxic and Hazardous Substances § 1915.1002 Coal tar pitch volatiles; interpretation of term. Note: The...

  3. 29 CFR 1915.1002 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 7 2012-07-01 2012-07-01 false Coal tar pitch volatiles; interpretation of term. 1915.1002 Section 1915.1002 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH... Toxic and Hazardous Substances § 1915.1002 Coal tar pitch volatiles; interpretation of term. Note: The...

  4. 29 CFR 1915.1002 - Coal tar pitch volatiles; interpretation of term.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Coal tar pitch volatiles; interpretation of term. 1915.1002 Section 1915.1002 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH... Toxic and Hazardous Substances § 1915.1002 Coal tar pitch volatiles; interpretation of term. Note: The...

  5. Coal-Tar-Based Pavement Sealcoat and PAHs: Implications for the Environment, Human Health, and Stormwater Management

    PubMed Central

    2012-01-01

    Coal-tar-based sealcoat products, widely used in the central and eastern U.S. on parking lots, driveways, and even playgrounds, are typically 20−35% coal-tar pitch, a known human carcinogen that contains about 200 polycyclic aromatic hydrocarbon (PAH) compounds. Research continues to identify environmental compartments—including stormwater runoff, lake sediment, soil, house dust, and most recently, air—contaminated by PAHs from coal-tar-based sealcoat and to demonstrate potential risks to biological communities and human health. In many cases, the levels of contamination associated with sealed pavement are striking relative to levels near unsealed pavement: PAH concentrations in air over pavement with freshly applied coal-tar-based sealcoat, for example, were hundreds to thousands of times higher than those in air over unsealed pavement. Even a small amount of sealcoated pavement can be the dominant source of PAHs to sediment in stormwater-retention ponds; proper disposal of such PAH-contaminated sediment can be extremely costly. Several local governments, the District of Columbia, and the State of Washington have banned use of these products, and several national and regional hardware and home-improvement retailers have voluntarily ceased selling them. PMID:22296333

  6. Coal-tar-based pavement sealcoat and PAHs: implications for the environment, human health, and stormwater management

    USGS Publications Warehouse

    Mahler, Barbara J.; Van Metre, Peter C.; Crane, Judy L.; Watts, Alison W.; Scoggins, Mateo; Williams, E. Spencer

    2012-01-01

    Coal-tar-based sealcoat products, widely used in the central and eastern U.S. on parking lots, driveways, and even playgrounds, are typically 20-35% coal-tar pitch, a known human carcinogen that contains about 200 polycyclic aromatic hydrocarbon (PAH) compounds. Research continues to identify environmental compartments—including stormwater runoff, lake sediment, soil, house dust, and most recently, air—contaminated by PAHs from coal-tar-based sealcoat and to demonstrate potential risks to biological communities and human health. In many cases, the levels of contamination associated with sealed pavement are striking relative to levels near unsealed pavement: PAH concentrations in air over pavement with freshly applied coal-tar-based sealcoat, for example, were hundreds to thousands of times higher than those in air over unsealed pavement. Even a small amount of sealcoated pavement can be the dominant source of PAHs to sediment in stormwater-retention ponds; proper disposal of such PAH-contaminated sediment can be extremely costly. Several local governments, the District of Columbia, and the State of Washington have banned use of these products, and several national and regional hardware and home-improvement retailers have voluntarily ceased selling them.

  7. Coal-tar-based pavement sealcoat and PAHs: implications for the environment, human health, and stormwater management.

    PubMed

    Mahler, Barbara J; Metre, Peter C Van; Crane, Judy L; Watts, Alison W; Scoggins, Mateo; Williams, E Spencer

    2012-03-20

    Coal-tar-based sealcoat products, widely used in the central and eastern U.S. on parking lots, driveways, and even playgrounds, are typically 20-35% coal-tar pitch, a known human carcinogen that contains about 200 polycyclic aromatic hydrocarbon (PAH) compounds. Research continues to identify environmental compartments-including stormwater runoff, lake sediment, soil, house dust, and most recently, air-contaminated by PAHs from coal-tar-based sealcoat and to demonstrate potential risks to biological communities and human health. In many cases, the levels of contamination associated with sealed pavement are striking relative to levels near unsealed pavement: PAH concentrations in air over pavement with freshly applied coal-tar-based sealcoat, for example, were hundreds to thousands of times higher than those in air over unsealed pavement. Even a small amount of sealcoated pavement can be the dominant source of PAHs to sediment in stormwater-retention ponds; proper disposal of such PAH-contaminated sediment can be extremely costly. Several local governments, the District of Columbia, and the State of Washington have banned use of these products, and several national and regional hardware and home-improvement retailers have voluntarily ceased selling them.

  8. Which Came First?

    NASA Image and Video Library

    2015-09-16

    The workings of the Martian winds are visible in this image of sand dunes trapped inside an unnamed crater in southern Terra Cimmeria captured by NASA Mars Reconnaissance Orbiter spacecraft. Many of the craters in the Southern highlands of Mars contain sand dunes, and HiRISE is still in the process of mapping these dunes and determining how active they are today. So far, the dunes in these craters appear to be a mixed bunch, with some dunes actively advancing while others seem to be frozen in place. This image will be compared to a previous picture, to see how these dunes have changed since 2008. The sand dunes are the large, branched ridges and dark patches that are conspicuous against the bright background, particularly in the northwest corner of our picture. There are also signs of two other wind-related processes: smaller, brighter ridges line the floor of the crater in regularly spaced rows. These are also windblown deposits, mysterious "transverse aeolian ridges" or TARs that are more common in the Martian tropics. Faint, irregular dark lines cross the dunes and the TARs, marking the tracks of dust devils that vacuum the surface during southern summer. So, which came first? We can untangle the history of these processes by looking at the picture more closely. Over most of the image, it is obvious that the dark sand dunes bury the bright TARs, meaning that the sand dunes are younger than the TARs. But this relationship is not so clear for the southernmost dune we see in this picture. Here, the TARs look like they extend into the dune and merge with ripples on the dune's surface, suggesting that the TARs might be younger than the dunes. The question can be resolved by carefully examining an enhanced color cutout. The TARs are brighter and redder than the sand dunes and this color persists on the crests of the TARs as the sand encroaches, burying the valleys first and then the slopes and finally the TAR crests. This tells us that the unusual appearance of the

  9. Risk Assessment for Children Exposed to Beach Sands Impacted by Oil Spill Chemicals.

    PubMed

    Black, Jennifer C; Welday, Jennifer N; Buckley, Brian; Ferguson, Alesia; Gurian, Patrick L; Mena, Kristina D; Yang, Ill; McCandlish, Elizabeth; Solo-Gabriele, Helena M

    2016-08-27

    Due to changes in the drilling industry, oil spills are impacting large expanses of coastlines, thereby increasing the potential for people to come in contact with oil spill chemicals. The objective of this manuscript was to evaluate the health risk to children who potentially contact beach sands impacted by oil spill chemicals from the Deepwater Horizon disaster. To identify chemicals of concern, the U.S. Environmental Protection Agency's (EPA's) monitoring data collected during and immediately after the spill were evaluated. This dataset was supplemented with measurements from beach sands and tar balls collected five years after the spill. Of interest is that metals in the sediments were observed at similar levels between the two sampling periods; some differences were observed for metals levels in tar balls. Although PAHs were not observed five years later, there is evidence of weathered-oil oxidative by-products. Comparing chemical concentration data to baseline soil risk levels, three metals (As, Ba, and V) and four PAHs (benzo[a]pyrene, benz[a]anthracene, benzo[b]fluoranthene, and dibenz[a,h]anthracene) were found to exceed guideline levels prompting a risk assessment. For acute or sub-chronic exposures, hazard quotients, computed by estimating average expected contact behavior, showed no adverse potential health effects. For cancer, computations using 95% upper confidence limits for contaminant concentrations showed extremely low increased risk in the 10(-6) range for oral and dermal exposure from arsenic in sediments and from dermal exposure from benzo[a]pyrene and benz[a]anthracene in weathered oil. Overall, results suggest that health risks are extremely low, given the limitations of available data. Limitations of this study are associated with the lack of toxicological data for dispersants and oil-spill degradation products. We also recommend studies to collect quantitative information about children's beach play habits, which are necessary to more

  10. Microbial metabolism alters pore water chemistry and increases consolidation of oil sands tailings.

    PubMed

    Arkell, Nicholas; Kuznetsov, Petr; Kuznetsova, Alsu; Foght, Julia M; Siddique, Tariq

    2015-01-01

    Tailings produced during bitumen extraction from surface-mined oil sands ores (tar sands) comprise an aqueous suspension of clay particles that remain dispersed for decades in tailings ponds. Slow consolidation of the clays hinders water recovery for reuse and retards volume reduction, thereby increasing the environmental footprint of tailings ponds. We investigated mechanisms of tailings consolidation and revealed that indigenous anaerobic microorganisms altered porewater chemistry by producing CO and CH during metabolism of acetate added as a labile carbon amendment. Entrapped biogenic CO decreased tailings pH, thereby increasing calcium (Ca) and magnesium (Mg) cations and bicarbonate (HCO) concentrations in the porewater through dissolution of carbonate minerals. Soluble ions increased the porewater ionic strength, which, with higher exchangeable Ca and Mg, decreased the diffuse double layer of clays and increased consolidation of tailings compared with unamended tailings in which little microbial activity was observed. These results are relevant to effective tailings pond management strategies. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  11. Identification of sources of tar balls deposited along the Southwest Caspian Coast, Iran using fingerprinting techniques.

    PubMed

    Shirneshan, Golshan; Bakhtiari, Alireza Riyahi; Memariani, Mahmoud

    2016-10-15

    In 2012, a significant number of tar balls occurred along the Southwest coasts of the Caspian Sea (Iran). Several oil fields of Turkmenistan, Azerbaijan and Iran might be sources of oil spills and lead to the formation of these tar balls. For source identification, 6 tar ball samples were collected from the Southwest beaches of the Caspian Sea and subjected to fingerprint analysis based on the distribution of the source-specific biomarkers of pentacyclic tri-terpanes and steranes. Comparing the diagenic ratios revealed that the tar balls were chemically similar and originated from the same source. Results of double ratio plots (e.g., C29/C30 versus ∑C31-C35/C30 and C28 αββ/(C27 αββ+C29 αββ) versus C29 αββ/(C27 αββ+C28 αββ)) in the tar balls and oils from Iran, Turkmenistan and Azerbaijan indicated that the tar balls might be the result of spills from Turkmenistan oil. Moreover, principle component analysis (PCA) using biomarker ratios on the tar balls and 20 crude oil samples from different wells of Azerbaijan, Iran and Turkmenistan oils showed that the tar balls collected at the Southwest beaches are highly similar to the Turkmenistan oil but one of the Azerbaijan oils (from Bahar field oils) was found to be also slightly close to the tar balls. The weathering characterizations based on the presence of UCM (unresolved complex mixture) and low/high molecular weight ratios (L/H) of alkanes and PAHs indicated the tar ball samples have been significantly influenced by natural weathering processes such as evaporation, photo-degradation and biodegradation. This is the first study of its kind in Iran to use fingerprinting for source identification of tar balls. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Coal-tar-based pavement sealcoat—Potential concerns for human health and aquatic life

    USGS Publications Warehouse

    Mahler, Barbara J.; Woodside, Michael D.; Van Metre, Peter C.

    2016-04-20

    Aquatic Life Concerns—Runoff from coal-tar-sealcoated pavement, even runoff collected more than 3 months after sealcoat application, is acutely toxic to fathead minnows and water fleas, two species commonly used to assess toxicity to aquatic life. Exposure to even highly diluted runoff from coal-tar-sealcoated pavement can cause DNA damage and impair DNA repair. These findings demonstrate that coal-tar-sealcoat runoff can remain a risk to aquatic life for months after application.

  13. Catalytic decomposition of tar derived from wood waste pyrolysis using Indonesian low grade iron ore as catalyst

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wicakso, Doni Rahmat; Chemical Engineering Department, Faculty of Engineering, Gadjah Mada University, Jalan Grafika No. 2 Bulaksumur, Yogyakarta, 55281; Sutijan

    Low grade iron ore can be used as an alternative catalyst for bio-tar decomposition. Compared to other catalysts, such as Ni, Rd, Ru, Pd and Pt, iron ore is cheaper. The objective of this research was to investigate the effect of using low grade iron ore as catalyst for tar catalytic decomposition in fixed bed reactor. Tar used in this experiment was pyrolysis product of wood waste while the catalyst was Indonesian low grade iron ore. The variables studied were temperatures between 500 – 600 °C and catalyst weight between 0 – 40 gram. The first step, tar was evaporatedmore » at 450 °C to produce tar vapor. Then, tar vapor was flowed to fixed bed reactor filled low grade iron ore. Gas and tar vapor from reactor was cooled, then the liquid and uncondensable gas were analyzed by GC/MS. The catalyst, after experiment, was weighed to calculate total carbon deposited into catalyst pores. The results showed that the tar components that were heavy and light hydrocarbon were decomposed and cracked within the iron ore pores to from gases, light hydrocarbon (bio-oil) and carbon, thus decreasing content tar in bio-oil and increasing the total gas product. In conclusion, the more low grade iron ore used as catalyst, the tar content in the liquid decrease, the H{sup 2} productivity increased and calorimetric value of bio-oil increased.« less

  14. Phytotoxicity and Plant Productivity Analysis of Tar-Enriched Biochars

    NASA Astrophysics Data System (ADS)

    Keller, M. L.; Masiello, C. A.; Dugan, B.; Rudgers, J. A.; Capareda, S. C.

    2008-12-01

    Biochar is one of the three by-products obtained by the pyrolysis of organic material, the other two being syngas and bio-oil. The pyrolysis of biomass has generated a great amount of interest in recent years as all three by-products can be put toward beneficial uses. As part of a larger project designed to evaluate the hydrologic impact of biochar soil amendment, we generated a biochar through fast pyrolysis (less than 2 minutes) of sorghum stock at 600°C. In the initial biochar production run, the char bin was not purged with nitrogen. This inadvertent change in pyrolysis conditions produced a fast-pyrolysis biochar enriched with tars. We chose not to discard this batch, however, and instead used it to test the impact of tar-enriched biochars on plants. A suite of phytotoxicity tests were run to assess the effects of tar-rich biochar on plant germination and plant productivity. We designed the experiment to test for negative effects, using an organic carbon and nutrient-rich, greenhouse- optimized potting medium instead of soil. We used Black Seeded Simpson lettuce (Lactuca sativa) as the test organism. We found that even when tars are present within biochar, biochar amendment up to 10% by weight caused increased lettuce germination rates and increased biomass productivity. In this presentation, we will report the statistical significance of our germination and biomass data, as well as present preliminary data on how biochar amendment affects soil hydrologic properties.

  15. Carbazole is a naturally occurring inhibitor of angiogenesis and inflammation isolated from antipsoriatic coal tar

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jack L. Arbiser; Baskaran Govindarajan; Traci E. Battle

    2006-06-15

    Coal tar is one of the oldest and an effective treatment for psoriasis. Coal tar has been directly applied to the skin, or used in combination with UV light as part of the Goeckerman treatment. The use of coal tar has caused long-term remissions in psoriasis, but has fallen out of favor because the treatment requires hospitalization and coal tar is poorly acceptable aesthetically to patients. Thus, determining the active antipsoriatic component of coal tar is of considerable therapeutic interest. We fractionated coal tar into its components, and tested them using the SVR angiogenesis inhibitor assay. Treatment of SVR endothelialmore » cells with coal tar fractions resulted in the isolation of a single fraction with antiangiogenic activity. The active antiangiogenic compound in coal tar is carbazole. In addition to antiangiogenic activity, carbazole inhibited the production of inflammatory IL-15 by human mononuclear cells. IL-15 is elevated in psoriasis and is thought to contribute to psoriatic inflammation. Carbazole treatment also reduced activity of inducible nitric oxide synthase (iNOS), which is proinflammatory and elevated in psoriasis. The effect of carbazole on upstream pathways in human psoriasis was determined, and carbazole was shown to inhibit signal transducer and activator of transcription (stat)3-mediated transcription, which has been shown to be relevant in human psoriasis. IL-15, iNOS, and stat3 activation require the activation of the small GTPase rac for optimal activity. Carbazole was found to inhibit rac activation as a mechanism for its inhibition of downstream inflammatory and angiogenic pathways. Given its antiangiogenic and anti-inflammatory activities, carbazole is likely a major component of the antipsoriatic activity of coal tar. Carbazole and derivatives may be useful in the therapy of human psoriasis.« less

  16. Reduced tar, nicotine, and carbon monoxide exposure while smoking ultralow- but not low-yield cigarettes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Benowitz, N.L.; Jacob, P. III; Yu, L.

    An unresolved public health issue is whether some modern cigarettes are less hazardous than other and whether patients who cannot stop smoking should be advised to switch to lower-yield cigarettes. The authors studied tar (estimated by urine mutagenicity), nicotine, and carbon monoxide exposure in habitual smokers switched from their usual brand to high- (15 mg of tar), low- (5 mg of tar), or ultralow-yield (1 mg of tar) cigarettes. There were no differences in exposure comparing high- or low-yield cigarettes, but tar and nicotine exposures were reduced by 49% and 56%, respectively, and carbon monoxide exposure by 36% while smokingmore » ultralow-yield cigarettes. Similarly, in 248 subjects smoking their self-selected brand, nicotine intake, estimated by blood concentrations of its metabolite continine, was 40% lower in those who smoked ultralow but no different in those smoking higher yields of cigarettes. The data indicate that ultralow-yield cigarettes do deliver substantial doses of tar, nicotine, and carbon monoxide, but that exposure are considerably less than for other cigarettes.« less

  17. Pollutant sensitivity of the endangered Tar River Spinymussel as assessed by single chemical and effluent toxicity tests

    USGS Publications Warehouse

    Augspurger, Thomas P.; Wang, Ning; Kunz, James L.; Ingersoll, Christopher G.

    2014-01-01

    The federally endangered Tar River spinymussel (Elliptio steinstansana) is endemic to the Tar River and Neuse River systems in North Carolina. The extent to which water quality limits Tar River spinymussels’ recovery is important to establish, and one aspect of that is understanding the species’ pollutant sensitivity. The primary objectives of this study were to 1) develop captive propagation and culture methods for Tar River spinymussels; 2) determine the pollutant sensitivity of captively propagated Tar River spinymussels; 3) examine the utility of the non-endangered yellow lance (Elliptio lanceolata), yellow lampmussel (Lampsilis cariosa) and notched rainbow (Villosa constricta) as surrogates for the Tar River spinymussels’ chemical sensitivity; 4) develop a 7-d method for conducting effluent toxicity tests starting with newly transformed mussels; 5) assess the toxicity of municipal wastewater effluents discharged into the Tar River spinymussels’ current and historic habitat; and, 6) evaluate the protection afforded by existing effluent toxicity test requirements.

  18. Effects of human chromosome 12 on interactions between Tat and TAR of human immunodeficiency virus type 1.

    PubMed Central

    Alonso, A; Cujec, T P; Peterlin, B M

    1994-01-01

    Rates of transcriptions of the human immunodeficiency virus are greatly increased by the viral trans activator Tat. In vitro, Tat binds to the 5' bulge of the trans-activation response (TAR) RNA stem-loop, which is present in all viral transcripts. In human cells, the central loop in TAR and its cellular RNA-binding proteins are also critical for the function of Tat. Previously, we demonstrated that in rodent cells (CHO cells), but not in those which contain the human chromosome 12 (CHO12 cells), Tat-TAR interactions are compromised. In this study, we examined the roles of the bulge and loop in TAR in Tat trans activation in these cells. Whereas low levels of trans activation depended solely on interactions between Tat and the bulge in CHO cells, high levels of trans activation depended also on interactions between Tat and the loop in CHO12 cells. Since the TAR loop binding proteins in these two cell lines were identical and different from their human counterpart, the human chromosome 12 does not encode TAR loop binding proteins. In vivo binding competition studies with TAR decoys confirmed that the binding of Tat to TAR is more efficient in CHO12 cells. Thus, the protein(s) encoded on human chromosome 12 helps to tether Tat to TAR via its loop, which results in high levels of trans activation. Images PMID:8083988

  19. Influence of cigarette filter ventilation on smokers' mouth level exposure to tar and nicotine.

    PubMed

    Caraway, John W; Ashley, Madeleine; Bowman, Sheri A; Chen, Peter; Errington, Graham; Prasad, Krishna; Nelson, Paul R; Shepperd, Christopher J; Fearon, Ian M

    2017-12-01

    Cigarette filter ventilation allows air to be drawn into the filter, diluting the cigarette smoke. Although machine smoking reveals that toxicant yields are reduced, it does not predict human yields. The objective of this study was to investigate the relationship between cigarette filter ventilation and mouth level exposure (MLE) to tar and nicotine in cigarette smokers. We collated and reviewed data from 11 studies across 9 countries, in studies performed between 2005 and 2013 which contained data on MLE from 156 products with filter ventilation between 0% and 87%. MLE among 7534 participants to tar and nicotine was estimated using the part-filter analysis method from spent filter tips. For each of the countries, MLE to tar and nicotine tended to decrease as filter ventilation increased. Across countries, per-cigarette MLE to tar and nicotine decreased as filter ventilation increased from 0% to 87%. Daily MLE to tar and nicotine also decreased across the range of increasing filter ventilation. These data suggest that on average smokers of highly ventilated cigarettes are exposed to lower amounts of nicotine and tar per cigarette and per day than smokers of cigarettes with lower levels of ventilation. Copyright © 2017 British American Tobacco. Published by Elsevier Inc. All rights reserved.

  20. Remediation of Coal Tar by STAR: Self-Sustaining Propagation Across Clean Gaps

    NASA Astrophysics Data System (ADS)

    Gerhard, J.; Brown, J.; Torero, J. L.; Grant, G.

    2016-12-01

    Self-sustaining Treatment for Active Remediation (STAR) is an emerging remediation technique which utilizes a subsurface smouldering reaction to destroy non-aqueous phase liquids (NAPL) in situ. The reaction is self-sustaining in that, once ignited, the destructive smouldering front will propagate outwards using only the energy embedded in the contaminant. However, it is known that coal tar can occur as both a continuous pool as well as in distinct seams separated by clean intervals. This study evaluated the hypothesis that the smouldering reaction can cross or `jump' clean gaps by transferring enough heat through the gap to re-ignite the reaction in the contaminated region beyond. Column and 2D box experiments were performed at two scales to determine the maximum clean gap which could be jumped vertically and horizontally. Once the maximum gap had been determined, sensitivity to various in situ and engineering control parameters were explored including: coal tar layer thickness, soil permeability, moisture content, NAPL saturation, and air injection flowrate. High resolution thermocouples informed the progress of the reaction, continuous gas emissions analysis revealed when the reaction was active and dormant, and detailed excavation mapped the extent of remediation and whether gaps were successfully jumped. The work demonstrated that substantial clean gaps, approaching the limit of the laboratory scale, can be jumped by the smouldering reaction using convective heat transfer. Also observed in some cases was the mobilization of pre-heated coal tar into the clean gaps and the reaction's ability to propagate through and destroy coal tar both adjacent to and within the gaps. This work is providing new insights into the robust nature of the technology for in situ applications, and indicating how extreme the heterogeneity has to be before the reaction is interrupted and a new ignition location would be required.

  1. Technology for the production of Zero Q.I pitch from coal tar

    NASA Astrophysics Data System (ADS)

    Karthik, K.; Kumar, K. Rajesh; Rao, C. V. Nageswara; Kumar, B. Vinod; Murty, J. V. S.

    2013-06-01

    Zero Quinoline Insolubles (Q.I) pitch is a special type of pitch obtained from pre-treatment of coal tar, which is converted into pitch. This is used for impregnation of electrodes for improving the strength, electrical properties and also used as a pre-cursor for Mesophase pitch for producing Mesophase pitch based carbon fibers, carbon foam, and Meso carbon micro beads. This paper discusses the technology of Q.I separation from Coal Tar by using decantation of Coal Tar mixed with Heavy Creosote Oil (HC Oil) at different temperatures. By this method we were able to produce the Zero Q.I pitch with a Q.I value of 0.1%.

  2. Exosomes from HIV-1-infected Cells Stimulate Production of Pro-inflammatory Cytokines through Trans-activating Response (TAR) RNA*

    PubMed Central

    Sampey, Gavin C.; Saifuddin, Mohammed; Schwab, Angela; Barclay, Robert; Punya, Shreya; Chung, Myung-Chul; Hakami, Ramin M.; Asad Zadeh, Mohammad; Lepene, Benjamin; Klase, Zachary A.; El-Hage, Nazira; Young, Mary; Iordanskiy, Sergey; Kashanchi, Fatah

    2016-01-01

    HIV-1 infection results in a chronic illness because long-term highly active antiretroviral therapy can lower viral titers to an undetectable level. However, discontinuation of therapy rapidly increases virus burden. Moreover, patients under highly active antiretroviral therapy frequently develop various metabolic disorders, neurocognitive abnormalities, and cardiovascular diseases. We have previously shown that exosomes containing trans-activating response (TAR) element RNA enhance susceptibility of undifferentiated naive cells to HIV-1 infection. This study indicates that exosomes from HIV-1-infected primary cells are highly abundant with TAR RNA as detected by RT-real time PCR. Interestingly, up to a million copies of TAR RNA/μl were also detected in the serum from HIV-1-infected humanized mice suggesting that TAR RNA may be stable in vivo. Incubation of exosomes from HIV-1-infected cells with primary macrophages resulted in a dramatic increase of proinflammatory cytokines, IL-6 and TNF-β, indicating that exosomes containing TAR RNA could play a direct role in control of cytokine gene expression. The intact TAR molecule was able to bind to PKR and TLR3 effectively, whereas the 5′ and 3′ stems (TAR microRNAs) bound best to TLR7 and -8 and none to PKR. Binding of TAR to PKR did not result in its phosphorylation, and therefore, TAR may be a dominant negative decoy molecule in cells. The TLR binding through either TAR RNA or TAR microRNA potentially can activate the NF-κB pathway and regulate cytokine expression. Collectively, these results imply that exosomes containing TAR RNA could directly affect the proinflammatory cytokine gene expression and may explain a possible mechanism of inflammation observed in HIV-1-infected patients under cART. PMID:26553869

  3. Effects of varying marijuana potency on deposition of tar and delta9-THC in the lung during smoking.

    PubMed

    Matthias, P; Tashkin, D P; Marques-Magallanes, J A; Wilkins, J N; Simmons, M S

    1997-12-01

    To determine whether smoking more, compared to less, potent marijuana (MJ) cigarettes to a desired level of intoxication ("high") reduces pulmonary exposure to noxious smoke components, in 10 habitual smokers of MJ, we measured respiratory delivery and deposition of tar and delta9-tetrahydrocannabinol (THC), carboxyhemoglobin (COHb) boost, smoking topography, including cumulative puff volume (CPV) and breathholding time, change in heart rate (deltaHR) and "high" during ad lib smoking of 0, 1.77, and 3.95% MJ cigarettes on 3 separate days. At each session, subjects had access to only a single MJ cigarette. On average, smoking topography and COHb boost did not differ across the different strengths of MJ, while THC delivery, as well as HR, were significantly greater (p < 0.01) and tar deposition significantly less (p < 0.03) for 3.95% than 1.77% MJ. Although individual adaptations in smoking topography for 3.95% compared to 1.77% MJ were highly variable, three subjects with the lowest 3.95% MJ:1.77% MJ ratios for CPV also displayed the lowest 3.95% MJ:1.77% MJ ratios for tar deposition. In vitro studies using a standardized smoking technique revealed a mean 25% lower tar yield from 3.95% than 1.77% MJ (p < 0.05), but no difference between 1.77% and 0% marijuana. Under the conditions of this study, we conclude that tar delivery is reduced relative to THC content in a minority of subjects, and this reduction appears to be due to a reduced intake of smoke (decreased CPV) and/or a reduced tar yield from the stronger MJ preparation.

  4. Physicochemical Approaches for the Remediation of Former Manufactured Gas Plant Tars

    NASA Astrophysics Data System (ADS)

    Hauswirth, S.; Miller, C. T.

    2014-12-01

    Former manufactured gas plant (FMGP) tars are one of the most challenging non-aqueous phase liquid (NAPL) contaminants to remediate due to their complex chemical composition, high viscosities, and ability to alter wettability. In this work, we investigate several in situ remediation techniques for the removal of tar from porous media. Batch and column experiments were conducted to test the effectiveness of mobilization, solubilization, and chemical oxidation remediation approaches. Alkaline (NaOH), surfactant (Triton X-100), and polymer (xanthan gum) agents were used in various combinations to reduce tar-water interfacial tension, increase flushing solution viscosity, and increase the solubilities of tar components. Base-activated sodium persulfate was used alone and in combination with surfactant to chemically oxidized tar components. The effectiveness of each method was assessed in terms of both removal of PAHs from the system and reduction of dissolved-phase effluent polycyclic aromatic hydrocarbon (PAH) concentrations. In column studies, alkaline-polymer (AP) and alkaline-surfactant-polymer (ASP) solutions efficiently mobilized 81-93% and 95-96% of residual PAHs, respectively, within two pore volumes. The impact of AP flushing on dissolved-phase PAH concentrations was relatively low; however, the concentrations of several low molar mass PAHs were significantly reduced after ASP flushing. Surfactant-polymer (SP) solutions removed over 99% of residual PAHs through a combination of mobilization and solubilization, and reduced the post-remediation, dissolved-phase total PAH concentration by 98.4-99.1%. Degradation of residual PAHs by base-activated sodium persulfate was relatively low (30-50%), and had little impact on dissolved-phase PAH concentrations.

  5. Thermal Cracking of Tars in a Continuously Fed Reactor with Steam

    DTIC Science & Technology

    2011-05-01

    Fluidized Bed using biomass 8 Tars  Mixture of organic components present in gasification product gas with high molecular weight hydrocarbons [MW...Disable sulfur removal systems FoulingPlugging [Ref. 3: Biomass Gasification – Tar and Particles in Product Gases Sampling and Analysis”, European...P., and Nussbaumer T., “Gas Cleaning Requirements for Internal Combustion Engine Applications of Fixed Bed Biomass Gasification ”, Biomass and

  6. Cold Preparation of Heroin in a Black Tar Market.

    PubMed

    Roth, Alexis M; Armenta, Richard F; Wagner, Karla D; Strathdee, Steffanie A; Goldshear, Jesse L; Cuevas-Mota, Jazmine; Garfein, Richard S

    2017-07-29

    Black tar heroin is typically prepared for injection with heat which decreases the risk of HIV transmission by inactivating the virus. We received reports that persons who inject drugs (PWID) in Tijuana, Baja California, Mexico, a black tar heroin market, were using only water to dissolve heroin. Because Tijuana abuts San Diego County, CA, United States, we undertook the present analyses to determine the prevalence of this practice among PWID in San Diego, California. PWID completed quarterly behavioral assessments and serological testing for blood-borne viruses. Bivariate and multivariable logistic regression models were constructed to assess for individual, social, and structural correlates of preparing heroin without heat within the preceding 6 months. Nearly half of black tar heroin users (149/305) reported they had prepared heroin without heat within 6 months. In multivariable analysis, cold preparation was independently associated with younger age (10 year decrease; AOR = 1.25; 95% CI 1.03, 1.53), more drug injecting acquaintances (per 5 acquaintance increase; AOR = 1.05; 95% CI 1.01, 1.09) and prefilled syringe use (injecting drugs from syringes that are already filled with drugs before purchase; AOR = 1.86; 95% CI 1.14, 3.02). Conclusions/Importance: To our knowledge, this is the first paper to report that PWID living in a black tar heroin market are preparing heroin without heat. Additional research is needed to determine whether this is an endemic practice or PWID are engaging in new forms of drug preparation in response to changes in the environment.

  7. The Auxin Biosynthetic TRYPTOPHAN AMINOTRANSFERASE RELATED TaTAR2.1-3A Increases Grain Yield of Wheat.

    PubMed

    Shao, An; Ma, Wenying; Zhao, Xueqiang; Hu, Mengyun; He, Xue; Teng, Wan; Li, Hui; Tong, Yiping

    2017-08-01

    Controlling the major auxin biosynthetic pathway to manipulate auxin content could be a target for genetic engineering of crops with desired traits, but little progress had been made because low or high auxin contents often cause developmental inhibition. Here, we performed a genome-wide analysis of bread wheat ( Triticum aestivum ) to identify the Tryptophan Aminotransferase of Arabidopsis1/Tryptophan Aminotransferase-Related (TAA1/TAR) genes that function in the tryptophan-dependent pathway of auxin biosynthesis. Sequence mining together with gene cloning identified 15 TaTAR genes, among which 12 and three genes were phylogenetically close to Arabidopsis ( Arabidopsis thaliana ) AtTAR2 and AtTAR3, respectively. TaTAR2.1 had the most abundant transcripts in the TaTAR2 genes and was expressed mainly in roots and up-regulated by low nitrogen (N) availability. Knockdown of TaTAR2.1 caused vegetative and reproductive deficiencies and impaired lateral root (LR) growth under both high- and low-N conditions. Overexpressing TaTAR2.1-3A in wheat enhanced LR branching, plant height, spike number, grain yield, and aerial N accumulation under different N supply levels. In addition, overexpressing TaTAR2.1-3A in Arabidopsis elevated auxin accumulation in the primary root tip, LR tip, LR primordia, and cotyledon and hypocotyl and increased primary root length, visible LR number, and shoot fresh weight under high- and low-N conditions. Our results indicate that TaTAR2.1 is critical for wheat growth and also shows potential for genetic engineering to reach the aim of improving the grain yield of wheat. © 2017 American Society of Plant Biologists. All Rights Reserved.

  8. Partitioning studies of coal-tar constituents in a two-phase contaminated ground-water system

    USGS Publications Warehouse

    Rostad, C.E.; Pereira, W.E.; Hult, M.F.

    1985-01-01

    Organic compounds derived from coal-tar wastes in a contaminated aquifer in St. Louis Park, Minnesota, were identified, and their partition coefficients between the tar phase and aqueous phase were determined and compared with the corresponding n-octanol/water partition coefficients. Coal tar contains numerous polycyclic aromatic compounds, many of which are suspected carcinogens or mutagens. Groundwater contamination by these toxic compounds may pose an environmental health hazard in nearby public water-supply wells. Fluid samples from this aquifer developed two phases upon settling: an upper aqueous phase, and a lower oily-tar phase. After separating the phases, polycyclic aromatic compounds in each phase were isolated using complexation with N-methyl-2-pyrrolidone and identified by fused-silica capillary gas chromatography/mass spectrometry. Thirty-one of the polycyclic aromatic compounds were chosen for further study from four different classes: 12 polycyclic aromatic hydrocarbons, 10 nitrogen heterocycles, 5 sulfur heterocycles, and 4 oxygen heterocycles. Within each compound class, the tar/water partition coefficients of these compounds were reasonably comparable with the respective n-octanol/water partition coefficient.

  9. A photographic method for estimating wear of coal tar sealcoat from parking lots

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mateo Scoggins; Tom Ennis; Nathan Parker

    2009-07-01

    Coal-tar-based sealcoat has been recognized as an important source of PAHs to the environment through wear and transport via stormwater runoff. Sealcoat removal rates have not been measured or even estimated in the literature due to the complex array of physical and chemical process involved. A photographic study was conducted that incorporates all sources of wear using 10 coal tar-sealed parking lots in Austin, Texas, with sealcoat age ranging from 0 to 5 years. Randomly located photographs from each parking lot were analyzed digitally to quantify black sealed areas versus lighter colored unsealed areas at the pixel level. The resultsmore » indicate that coal tar sealcoat wears off of the driving areas of parking lots at a rate of approximately 4.7% per year, and from the parking areas of the lots at a rate of approximately 1.4% per year. The overall annual loss of sealcoat was calculated at 2.4%. This results in an annual delivery to the environment of 0.51 g of PAHs per m{sup 2} of coal tar-sealed parking lot. These values provide a more robust and much higher estimate of loading of PAHs from coal tar sealcoated parking lots when compared to other available measures. 20 refs., 6 figs.« less

  10. Morphology of transverse aeolian ridges (TARs) on Mars from a large sample: Further evidence of a megaripple origin?

    NASA Astrophysics Data System (ADS)

    Hugenholtz, Chris H.; Barchyn, Thomas E.; Boulding, Adam

    2017-04-01

    Using HiRISE digital terrain models (DTMs), we developed a large morphological dataset to examine the three-dimensional shape, size, and scaling of Martian transverse aeolian ridges (TARs). Considerable debate exists on the characteristic morphology of TARs and the origins of these enigmatic bedforms. Some researchers suggest polygenesis or multiple classes of similar bedforms. Reliably characterizing the morphology of TARs is an essential prerequisite to developing and evaluating process-based models of TAR genesis and unraveling aeolian processes on the surface of Mars. We present measurements of TAR morphology from a large, DTM-derived dataset (n = 2295). We focused on TARs with 'simple' morphologies in order enable more defensible discretization. Histograms and cumulative log-frequency plots of morphometric parameters (length, width, height, elongation ratio, and wavelength) indicate the sample represents a continuum of bedforms from a single population. A typical TAR from our dataset is 88.5 m long (longest planview axis), 17.3 m wide (shortest planview axis), 1.3 m tall, and has a wavelength of 25.8 m. Combined with these data, the bulk of evidence presented to date suggests that interpreting TARs as megaripples is the most viable working hypothesis.

  11. Submarine sand ridges and sand waves in the eastern part of the China Sea

    NASA Astrophysics Data System (ADS)

    Wu, Ziyin; Li, Shoujun; Shang, Jihong; Zhou, Jieqiong; Zhao, Dineng; Liang, Yuyang

    2016-04-01

    Integrated with multi-beam and single-beam echo sounding data, as well as historical bathymetric data, submarine bathymetric maps of the eastern part of the China Sea, including the Bohai Sea, Huanghai Sea, and East China Sea, are constructed to systematically study submarine sand ridges and sand waves in the eastern part of the China Sea, combined with high-resolution seismic, sub-bottom profile and borehole data. Submarine sand ridges are extraordinarily developed in the eastern part of the China Sea, and 7 sand ridge areas can be divided from north to south, that is, the Laotieshan Channel sand ridge area in the Bohai Sea, the Korea Bay sand ridge area in the southern Huanghai Sea, the sand ridge area in the eastern Huanghai islands and the Huanghai Troughs, the Jianggang sand ridge area in the western Huanghai Sea, the sand ridge area in the East China Sea shelf, and the sand ridge and sand wave area in the Taiwan Strait and Taiwan Banks. The distribution area of the sand ridges and sand waves covers more than 450,000 km2, wherein ~10,000 km2 in the Bohai Bay, ~200,000 km2 in the Huanghai Sea, ~200,000 km2 in the East China Sea shelf, and ~40,000 km2 in the Taiwan Strait and Taiwan Banks, respectively. The great mass of sand ridges are distributed within water depth of 5-160 m, with a total length of over 160 km and a main width of 5-10 km. The inner structure of the sand ridges presents features of high-angle inclined beddings, with main lithology of sands, sand-mud alternations partly visible, and a small number of mud cores. Dating results indicate that the sand ridges in the eastern part of the China Sea are mainly developed in the Holocene. Sea-level variation dominates the sand ridge evolution in the eastern part of the China Sea since the LGM, and the sand ridges developed in the area of < 60m water depth are appeared in bad activity, meanwhile sand ridges with good activity are still developed in large scale.

  12. TarPmiR: a new approach for microRNA target site prediction.

    PubMed

    Ding, Jun; Li, Xiaoman; Hu, Haiyan

    2016-09-15

    The identification of microRNA (miRNA) target sites is fundamentally important for studying gene regulation. There are dozens of computational methods available for miRNA target site prediction. Despite their existence, we still cannot reliably identify miRNA target sites, partially due to our limited understanding of the characteristics of miRNA target sites. The recently published CLASH (crosslinking ligation and sequencing of hybrids) data provide an unprecedented opportunity to study the characteristics of miRNA target sites and improve miRNA target site prediction methods. Applying four different machine learning approaches to the CLASH data, we identified seven new features of miRNA target sites. Combining these new features with those commonly used by existing miRNA target prediction algorithms, we developed an approach called TarPmiR for miRNA target site prediction. Testing on two human and one mouse non-CLASH datasets, we showed that TarPmiR predicted more than 74.2% of true miRNA target sites in each dataset. Compared with three existing approaches, we demonstrated that TarPmiR is superior to these existing approaches in terms of better recall and better precision. The TarPmiR software is freely available at http://hulab.ucf.edu/research/projects/miRNA/TarPmiR/ CONTACTS: haihu@cs.ucf.edu or xiaoman@mail.ucf.edu Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.

  13. Tar analysis from biomass gasification by means of online fluorescence spectroscopy

    NASA Astrophysics Data System (ADS)

    Baumhakl, Christoph; Karellas, Sotirios

    2011-07-01

    Optical methods in gas analysis are very valuable mainly due to their non-intrusive character. That gives the possibility to use them for in-situ or online measurements with only optical intervention in the measurement volume. In processes like the gasification of biomass, it is of high importance to monitor the gas quality in order to use the product gas in proper machines for energy production following the restrictions in the gas composition but also improving its quality, which leads to high efficient systems. One of the main problems in the biomass gasification process is the formation of tars. These higher hydrocarbons can lead to problems in the operation of the energy system. Up to date, the state of the art method used widely for the determination of tars is a standardized offline measurement system, the so-called "Tar Protocol". The aim of this work is to describe an innovative, online, optical method for determining the tar content of the product gas by means of fluorescence spectroscopy. This method uses optical sources and detectors that can be found in the market at low cost and therefore it is very attractive, especially for industrial applications where cost efficiency followed by medium to high precision are of high importance.

  14. Skin cancer in patients with psoriasis treated with coal tar. A 25-year follow-up study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pittelkow, M.R.; Perry, H.O.; Muller, S.A.

    1981-08-01

    For many years, crude coal tar has been used for the treatment of psoriasis. The possible carcinogenic effect of crude coal tar and ultraviolet (UV) radiation (Goeckerman regimen), considered individually or in combination, has been of some concern to physicians. A 25-year follow-up study was completed on 280 patients with psoriasis who were hospitalized and treated with crude coal tar and UV radiation at the Mayo Clinic, Rochester, Minn, during the years 1950 through 1954. The results of this study suggest that the incidence of skin cancer is not appreciably increased above the expected incidence for the general population whenmore » patients are treated with coal tar ointments. It seems that the Goeckerman regimen (topical crude coal tar combined with UV radiation) can be used with minimal risk for skin cancer in the treatment of psoriasis.« less

  15. Volatilization of polycyclic aromatic hydrocarbons from coal-tar-sealed pavement

    USGS Publications Warehouse

    Van Metre, Peter C.; Majewski, Michael S.; Mahler, Barbara J.; Foreman, William T.; Braun, Christopher L.; Wilson, Jennifer T.; Burbank, Teresa L.

    2012-01-01

    Coal-tar-based pavement sealants, a major source of PAHs to urban water bodies, are a potential source of volatile PAHs to the atmosphere. An initial assessment of volatilization of PAHs from coal-tar-sealed pavement is presented here in which we measured summertime gas-phase PAH concentrations 0.03 m and 1.28 m above the pavement surface of seven sealed (six with coal-tar-based sealant and one with asphalt-based sealant) and three unsealed (two asphalt and one concrete) parking lots in central Texas. PAHs also were measured in parking lot dust. The geometric mean concentration of the sum of eight frequently detected PAHs (ΣPAH8) in the 0.03-m samples above sealed lots (1320 ng m-3) during the hottest part of the day was 20 times greater than that above unsealed lots (66.5 ng m-3). The geometric mean concentration in the 1.28-m samples above sealed lots (138 ng m-3) was five times greater than above unsealed lots (26.0 ng m-3). Estimated PAH flux from the sealed lots was 60 times greater than that from unsealed lots (geometric means of 88 and 1.4 μg m-2 h-1, respectively). Although the data set presented here is small, the much higher estimated fluxes from sealed pavement than from unsealed pavement indicate that coal-tar-based sealants are emitting PAHs to urban air at high rates compared to other paved surfaces.

  16. Iron(II) supramolecular helicates interfere with the HIV-1 Tat–TAR RNA interaction critical for viral replication

    PubMed Central

    Malina, Jaroslav; Hannon, Michael J.; Brabec, Viktor

    2016-01-01

    The interaction between the HIV-1 transactivator protein Tat and TAR (transactivation responsive region) RNA, plays a critical role in HIV-1 transcription. Iron(II) supramolecular helicates were evaluated for their in vitro activity to inhibit Tat–TAR RNA interaction using UV melting studies, electrophoretic mobility shift assay, and RNase A footprinting. The results demonstrate that iron(II) supramolecular helicates inhibit Tat-TAR interaction at nanomolar concentrations by binding to TAR RNA. These studies provide a new insight into the biological potential of metallosupramolecular helicates. PMID:27405089

  17. Iron(II) supramolecular helicates interfere with the HIV-1 Tat-TAR RNA interaction critical for viral replication.

    PubMed

    Malina, Jaroslav; Hannon, Michael J; Brabec, Viktor

    2016-07-12

    The interaction between the HIV-1 transactivator protein Tat and TAR (transactivation responsive region) RNA, plays a critical role in HIV-1 transcription. Iron(II) supramolecular helicates were evaluated for their in vitro activity to inhibit Tat-TAR RNA interaction using UV melting studies, electrophoretic mobility shift assay, and RNase A footprinting. The results demonstrate that iron(II) supramolecular helicates inhibit Tat-TAR interaction at nanomolar concentrations by binding to TAR RNA. These studies provide a new insight into the biological potential of metallosupramolecular helicates.

  18. Process for removing heavy metal compounds from heavy crude oil

    DOEpatents

    Cha, Chang Y.; Boysen, John E.; Branthaver, Jan F.

    1991-01-01

    A process is provided for removing heavy metal compounds from heavy crude oil by mixing the heavy crude oil with tar sand; preheating the mixture to a temperature of about 650.degree. F.; heating said mixture to up to 800.degree. F.; and separating tar sand from the light oils formed during said heating. The heavy metals removed from the heavy oils can be recovered from the spent sand for other uses.

  19. Crystallization and preliminary X-ray diffraction analysis of the periplasmic domain of the Escherichia coli aspartate receptor Tar and its complex with aspartate

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mise, Takeshi; Matsunami, Hideyuki; Samatey, Fadel A.

    The periplasmic domain of the E. coli aspartate receptor Tar was cloned, expressed, purified and crystallized with and without bound ligand. The crystals obtained diffracted to resolutions of 1.58 and 1.95 Å, respectively. The cell-surface receptor Tar mediates bacterial chemotaxis toward an attractant, aspartate (Asp), and away from a repellent, Ni{sup 2+}. To understand the molecular mechanisms underlying the induction of Tar activity by its ligands, the Escherichia coli Tar periplasmic domain with and without bound aspartate (Asp-Tar and apo-Tar, respectively) were each crystallized in two different forms. Using ammonium sulfate as a precipitant, crystals of apo-Tar1 and Asp-Tar1 weremore » grown and diffracted to resolutions of 2.10 and 2.40 Å, respectively. Alternatively, using sodium chloride as a precipitant, crystals of apo-Tar2 and Asp-Tar2 were grown and diffracted to resolutions of 1.95 and 1.58 Å, respectively. Crystals of apo-Tar1 and Asp-Tar1 adopted space group P4{sub 1}2{sub 1}2, while those of apo-Tar2 and Asp-Tar2 adopted space groups P2{sub 1}2{sub 1}2{sub 1} and C2, respectively.« less

  20. Risk Assessment for Children Exposed to Beach Sands Impacted by Oil Spill Chemicals

    PubMed Central

    Black, Jennifer C.; Welday, Jennifer N.; Buckley, Brian; Ferguson, Alesia; Gurian, Patrick L.; Mena, Kristina D.; Yang, Ill; McCandlish, Elizabeth; Solo-Gabriele, Helena M.

    2016-01-01

    Due to changes in the drilling industry, oil spills are impacting large expanses of coastlines, thereby increasing the potential for people to come in contact with oil spill chemicals. The objective of this manuscript was to evaluate the health risk to children who potentially contact beach sands impacted by oil spill chemicals from the Deepwater Horizon disaster. To identify chemicals of concern, the U.S. Environmental Protection Agency’s (EPA’s) monitoring data collected during and immediately after the spill were evaluated. This dataset was supplemented with measurements from beach sands and tar balls collected five years after the spill. Of interest is that metals in the sediments were observed at similar levels between the two sampling periods; some differences were observed for metals levels in tar balls. Although PAHs were not observed five years later, there is evidence of weathered-oil oxidative by-products. Comparing chemical concentration data to baseline soil risk levels, three metals (As, Ba, and V) and four PAHs (benzo[a]pyrene, benz[a]anthracene, benzo[b]fluoranthene, and dibenz[a,h]anthracene) were found to exceed guideline levels prompting a risk assessment. For acute or sub-chronic exposures, hazard quotients, computed by estimating average expected contact behavior, showed no adverse potential health effects. For cancer, computations using 95% upper confidence limits for contaminant concentrations showed extremely low increased risk in the 10−6 range for oral and dermal exposure from arsenic in sediments and from dermal exposure from benzo[a]pyrene and benz[a]anthracene in weathered oil. Overall, results suggest that health risks are extremely low, given the limitations of available data. Limitations of this study are associated with the lack of toxicological data for dispersants and oil-spill degradation products. We also recommend studies to collect quantitative information about children’s beach play habits, which are necessary to more

  1. High temperature thermal energy storage in moving sand

    NASA Technical Reports Server (NTRS)

    Turner, R. H.; Awaya, H. I.

    1978-01-01

    Several high-temperature (to 500 C) heat-storage systems using sand as the storage medium are described. The advantages of sand as a storage medium include low cost for sand, widespread availability, non-toxicity, non-degradation characteristics, easy containment, and safety. The systems considered include: stationary sand with closely spaced tubes throughout the volume, the use of a fluidized bed, use of conveyor belt transporter, and the use of a blower rapid transport system. For a stationary sand bed, very close spacing of heat transfer tubes throughout the volume is required, manifesting as high power related system cost. The suggestion of moving sand past or around pipes is intended to reduce the power related costs at the penalty of added system complexity. Preliminary system cost estimates are offered. These rough calculations indicate that mobile sand heat storage systems cost less than the stationary sand approach.

  2. Volatilization of polycyclic aromatic hydrocarbons from coal-tar-sealed pavement.

    PubMed

    Van Metre, Peter C; Majewski, Michael S; Mahler, Barbara J; Foreman, William T; Braun, Christopher L; Wilson, Jennifer T; Burbank, Teresa L

    2012-06-01

    Coal-tar-based pavement sealants, a major source of PAHs to urban water bodies, are a potential source of volatile PAHs to the atmosphere. An initial assessment of volatilization of PAHs from coal-tar-sealed pavement is presented here in which we measured summertime gas-phase PAH concentrations 0.03 m and 1.28 m above the pavement surface of seven sealed (six with coal-tar-based sealant and one with asphalt-based sealant) and three unsealed (two asphalt and one concrete) parking lots in central Texas. PAHs also were measured in parking lot dust. The geometric mean concentration of the sum of eight frequently detected PAHs (ΣPAH(8)) in the 0.03-m samples above sealed lots (1320 ng m(-3)) during the hottest part of the day was 20 times greater than that above unsealed lots (66.5 ng m(-3)). The geometric mean concentration in the 1.28-m samples above sealed lots (138 ng m(-3)) was five times greater than above unsealed lots (26.0 ng m(-3)). Estimated PAH flux from the sealed lots was 60 times greater than that from unsealed lots (geometric means of 88 and 1.4 μg m(-2) h(-1), respectively). Although the data set presented here is small, the much higher estimated fluxes from sealed pavement than from unsealed pavement indicate that coal-tar-based sealants are emitting PAHs to urban air at high rates compared to other paved surfaces. Published by Elsevier Ltd.

  3. Development of secondary chamber for tar cracking-improvement of wood pyrolysis performance in pre-vacuum chamber

    NASA Astrophysics Data System (ADS)

    Siahaan, S.; Homma, H.; Homma, H.

    2018-02-01

    Energy crisis and global warming, in other words, climate change are critical topics discussed in various parts of the world. Global warming primarily result from too much emission of carbon dioxide (CO2) in the atmosphere. To mitigate global warming, or climate change and improve electrification in rural areas, wood pyrolysis technology is developed in a laboratory scale, of which gases are directly applicable to the gas engine generator. Our laboratory has developed a prototype of wood pyrolysis plant with a pre-vacuum chamber. However, tar yield was around 40 wt% of feedstock. This research aims to reduce tar yield by secondary tar cracking. For the secondary tar cracking, a secondary pre-vacuum chamber is installed after primary pre-vacuum chamber. Gases generated in the primary pre-vacuum chamber are lead into the secondary chamber that is heated up to 1000 K. This paper reports performance of the secondary chamber for secondary tar cracking in homogeneous mode and heterogeneous mode with char.

  4. Polycyclic aromatic hydrocarbon (PAHs) and hopanes in stranded tar-balls on the coasts of Peninsular Malaysia: applications of biomarkers for identifying sources of oil pollution.

    PubMed

    Zakaria, M P; Okuda, T; Takada, H

    2001-12-01

    Malaysian coasts are subjected to various threats of petroleum pollution including routine and accidental oil spill from tankers, spillage of crude oils from inland and off-shore oil fields, and run-off from land-based human activities. Due to its strategic location, the Straits of Malacca serves as a major shipping lane. This paper expands the utility of biomarker compounds, hopanes, in identifying the source of tar-balls stranded on Malaysian coasts. 20 tar-ball samples collected from the east and west coast were analyzed for hopanes and polycyclic aromatic hydrocarbons (PAHs). Four of the 13 tar-ball samples collected from the west coast of Peninsular Malaysia were identified as the Middle East crude oil (MECO) based on their biomarker signatures, suggesting tanker-derived sources significantly contributing the petroleum pollution in the Straits of Malacca. The tar-balls found on the east coast seem to originate from the offshore oil platforms in the South China Sea. The presence of South East Asian crude oil (SEACO) tar-balls on the west coast carry several plausible explanations. Some of the tar-balls could have been transported via sea currents from the east coast. The tankers carrying SEACO to other countries could have accidentally spilt the oil as well. Furthermore, discharge of tank washings and ballast water from the tankers were suggested based on the abundance in higher molecular weight n-alkanes and the absence of unresolved complex mixture (UCM) in the tar-ball samples. The other possibilities are that the tar-balls may have been originated from the Sumatran oil fields and spillage of domestic oil from oil refineries in Port Dickson and Malacca. The results of PAHs analysis suggest that all the tar-ball samples have undergone various extent of weathering through evaporation, dissolution and photooxidation.

  5. A study of global sand seas

    USGS Publications Warehouse

    McKee, Edwin D.

    1979-01-01

    The birth of the idea that led to this publication on "Global Sand Seas" dates back to the late 1920's. At that time I was engaged in a study of the Coconino Sandstone of Arizona's Grand Canyon. Considerable controversy existed then as to whether this sandstone was a subaqueous deposit or was composed of wind-formed dunes. It became apparent that definitive literature was sparse or lacking on types of dunes, global distribution of these types, the mechanics of their development, the precise nature of their internal structure of cross-stratificiation, and the relation of wind systems to these sand forms. Especially lacking were data on criteria that could confidently be used in the recognition of ancient dunes. The common denominator in this publication is eolian sand bodies. Although the book is concerned primarily with desert sand seas, the subject matter is not restricted to deserts; it includes many references to deposits of coastal sand and to sand bodies in humid climates. Nor does the book deal exclusively with dunes, which, according to most definitions, involve mounds or hills. Many references are made to sand sheets, sand stringers, and other types of sand deposits that have no prominent topographic expression. All sand bodies accumulated by the action of wind are discussed. Chapters A-J of this publication are primarily topical. Chapters cover the grain texture, the color, and the structure of modern dunes and other eolian sands. Special treatment is given to the relation of wind data to dune interpretation, the evolution of form in current-deposited sand bodies as determined from experimental studies, and the discriminant analysis technique for differentiating between coastal and inland desert sands. This topical part of the publication also includes an analysis of criteria used in ancient deposits to interpret their eolian genesis and a consideration of economic application of the principles described, including a discussion of potentials and problems

  6. Social movement heterogeneity in public policy framing: A multi-stakeholder analysis of the Keystone XL pipeline

    NASA Astrophysics Data System (ADS)

    Wesley, David T. A.

    In 2011, stakeholders with differing objectives formed an alliance to oppose the Keystone XL heavy oil pipeline. The alliance, which came to be known as "Tar Sands Action," implemented various strategies, some of which were more successful than others. Tar Sands Action was a largely heterogeneous alliance that included indigenous tribes, environmentalists, ranchers, landowners, and trade unions, making it one of the more diverse social movement organizations in history. Each of these stakeholder categories had distinct demographic structures, representing an array of racial, ethnic, educational, occupational, and political backgrounds. Participants also had differing policy objectives that included combating climate change and protecting jobs, agricultural interests, water resources, wildlife, and human health. The current dissertation examines the Tar Sands Action movement to understand how heterogeneous social movement organizations mobilize supporters, maintain alliances, and create effective frames to achieve policy objectives. A multi-stakeholder analysis of the development, evolution and communication of frames concerning the Keystone XL controversy provides insight into the role of alliances, direct action, and the news media in challenging hegemonic frames. Previous research has ignored the potential value that SMO heterogeneity provides by treating social movements as culturally homogenous. However, diversity has been shown to affect performance in business organizations. The current study demonstrates that under some circumstances, diversity can also improve policy outcomes. Moreover, policy frames are shown to be more effective in sustaining news media and public interest through a process the author calls dynamic frame sequencing (DFS). DFS refers to a process implementing different stakeholder frames at strategically opportune moments. Finally, Tar Sands Action was one of the first SMOs to rely heavily on social media to build alliances, disseminate

  7. Optical, Physical and Chemical Properties of Tar Balls Observed During the Yosemite Aerosol Characterization Study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hand, Jenny L.; Malm, W. C.; Laskin, Alexander

    2005-11-09

    The Yosemite Aerosol Characterization Study of summer 2002 (YACS) occurred during an active fire season in the western U. S., and provided an opportunity to investigate many unresolved issues related to the radiative effects of biomass burning aerosols. Single particle analysis was performed on field collected aerosol samples using an array of electron microscopy techniques. Amorphous carbon spheres, or “tar balls”, were present in samples collected during episodes of high particle light scattering coefficients that occurred during the peak of a smoke/haze event. The highest concentrations of light-absorbing carbon from a dual-wavelength aethalometer (λ = 370 and 880 nm) occurredmore » during periods when the particles were predominantly tar balls, indicating they do absorb light in the UV and near-IR range of the solar spectrum. Closure experiments of mass concentrations and light scattering coefficients during periods dominated by tar balls did not require any distinct assumptions of organic carbon molecular weight correction factors, density, or refractive index compared to periods dominated by other types of organic carbon aerosols. Measurements of the hygroscopic behavior of tar balls using an environmental SEM indicate that tar balls do not exhibit deliquescence, but do uptake some water at high (~83 %) relative humidity. The ability of tar balls to efficiently scatter and absorb light, and to absorb water has important implications for their role in regional haze and climate fence.« less

  8. Methotrexate iontophoresis versus coal tar ointment in palmoplantar psoriasis: A pilot study.

    PubMed

    Haseena, K; George, Sandhya; Riyaz, Najeeba; Sasidharanpillai, Sarita; Puthussery, Paul V

    2017-01-01

    Palmoplantar psoriasis is often disabling and refractory to conventional therapy. Systemic drugs are indicated in its severe form, but side effects are a concern with their use. Methotrexate is one such systemic drug which is effective and cheap. To reduce systemic toxicity, methotrexate has been tried topically but results have been inconsistent due to poor drug penetration into the skin by passive diffusion. Iontophoresis may enhance its absorption and efficacy. To evaluate the efficacy and safety of topical methotrexate iontophoresis in comparison with coal tar ointment in the treatment of palmoplantar psoriasis. Thirty-one patients with palmar and/or plantar psoriasis were selected for the study and 28 patients completed it. The side having more severe involvement was treated while the other palm/sole served as a control. Iontophoresis using methotrexate solution was carried out on the study palm/sole with the injectable preparation of methotrexate (50 mg/2 ml) once a week for the first 4 weeks and subsequently every two weeks, for a total of six sittings. The control palm/sole was treated with coal tar ointment on other days. Erythema, scaling, induration and fissuring scores were noted in both groups before and after treatment. Both study and control groups showed decreases in scores but the reduction was more in the study group, the difference being statistically significant. Drawbacks of our study include the small sample size and the lack of follow-up. The study and control arms were not exactly matched and the study was not blinded. Methotrexate iontophoresis was safe and more effective than coal tar ointmentin palmoplantarpsoriasis.

  9. Comparative evaluation of topical calcipotriol versus coal tar and salicylic acid ointment in chronic plaque psoriasis.

    PubMed

    Singh, Preeti; Gupta, Surabhi; Abidi, Afroz; Krishna, Arvind

    2013-08-01

    Calcipotriol is a newer topical treatment option available for plaque psoriasis and coal tar being one of the oldest treatment and still in use. To evaluate and compare the differences in terms of efficacy, safety and relapse with Calcipotriol 0.005% (50 mcg/gm) and 6% coal tar and 3% salicylic ointment in patients with Plaque psoriasis. SETTING and Study conducted on 60 patients of plaque psoriasis, who attended the skin OPD in our hospital. The patients with mild to moderate plaque psoriasis were selected. 60 patients were enrolled for the study after obtaining informed consent. Subjects were asked to apply Calcipotriol 0.005% (50 mcg/gm) (Heximar Win care) twice a day on the right side plaques and on left side plaques, Petroleum jelly (Vaseline) in the morning and 6% coal tar and 3% salicylic ointment (Protar® Percos) at nighttime. PASI score was used to assess the reponse to therapy at 2nd, 4th, 6th and 8th week. After treatment subjects were observed for 6 weeks for any relapse. It was done by paired t-test and independent sample t-test. The results showed that statistically significant difference was seen in the mean percentage reduction of PASI score between both the groups, at all the assessment visits, 2, 4, 6, and 8 weeks, the mean percentage reduction at 2 weeks for calcipotriol being 21±12.06 and for coal tar being 13.44±11.19 (P=0.000), at 4 weeks for calcipotriol was 40±16.71 and for coal tar 25±99 (P=0.000), at 6 weeks for calcipotriol was 53.99+-22.43 and for coal tar 41±21.23 (P=0.002), at 8 weeks for calcipotriol was 62.73±24.04 and for coal tar was 51.53±23.27 (P=0.11). Relapse was seen in 5/60 (8.3%) of patients on calcipotriol treated side and 9/60 (15%) of patients with coal tar treated side. Thus it can be concluded that calcipotriol cream is more efficacious when compared with coal tar and does have a quick response. It is well tolerated and acceptable cosmetically.

  10. Disturbance of the inclined inserting-type sand fence to wind-sand flow fields and its sand control characteristics

    NASA Astrophysics Data System (ADS)

    Cheng, Jian-jun; Lei, Jia-qiang; Li, Sheng-yu; Wang, Hai-feng

    2016-06-01

    The inclined inserting-type sand fence is a novel sand retaining wall adopted along the Lanxin High-Speed Railway II in Xinjiang for controlling and blocking sand movement. To verify the effectiveness of the new fence structure for sand prevention, a wind tunnel test was used for flow field test simulation of the sand fence. The results indicate that the inclined inserting-type sand fence was able to deflect the flow of the sand and was able to easily form an upward slant acceleration zone on the leeward side of the sand fence. As shown by the percentage change in sand collection rates on the windward side and the leeward side of the sand fence, the sand flux per unit area at 4 m height in the slant upward direction increased on the leeward side of the inclined inserting-type sand fence. By comparing the flow fields, this site is an acceleration zone, which also reaffirms the correspondence of wind-sand flow fields with the spatial distribution characteristic of the wind-carried sand motion. The field sand collection data indicates that under the effects of the inclined inserting-type sand fence, the sandy air currents passing in front and behind the sand fence not only changed in quality, but the grain composition and particle size also significantly changed, suggesting that the inclined inserting-type sand fence has a sorting and filtering effect on the sandy air currents that passed through. The fence retained coarse particulates on the windward side and fine particulates within the shade of the wind on the leeward side.

  11. Meta-analysis of lung cancer in asphalt roofing and paving workers with external adjustment for confounding by coal tar

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fayerweather, W.E.

    2007-07-01

    The study's objectives were to update Partanen's and Boffetta's 1994 meta-analysis of lung cancer among roofing and paving asphalt workers and explore the role of coal tar in explaining the statistical heterogeneity among these studies. Information retrieval strategies and eligibility criteria were defined for identifying the epidemiologic studies to be included in the analysis. The relative risk ratio (RR) for lung cancer was selected as the effect measure of interest. Coal tar bias factors were developed and used to externally adjust each eligible study's published RR for confounding by coal tar. The meta-Relative Risk (meta-RR) and its variance were estimatedmore » by general variance-based methods. Heterogeneity of the RRs was assessed by heterogeneity chi-square and I{sup 2} tests. The results from this update were similar to those in Partanen's and Boffetta's original meta-analysis. Although the meta-RRs for the roofers and the pavers were no longer statistically significantly different from one another, significant heterogeneity remained within each of the coal tar-adjusted sectors. Meta-analysis of non-experimental epidemiologic studies is subject to significant uncertainties as is externally correcting studies for confounding. Given these uncertainties, the specific quantitative estimates in this (or any similar) analysis must be viewed with caution. Nevertheless, this analysis provides support for the hypothesis proposed by several major reviewers that confounding by coal tar-related PAH exposures may explain most or all of the lung cancer risks found in the epidemiologic literature on asphalt roofing and paving workers.« less

  12. Ligand-induced changes in 2-aminopurine fluorescence as a probe for small molecule binding to HIV-1 TAR RNA

    PubMed Central

    BRADRICK, THOMAS D.; MARINO, JOHN P.

    2004-01-01

    Replication of human immunodeficiency virus type 1 (HIV-1) is regulated in part through an interaction between the virally encoded trans-activator protein Tat and the trans-activator responsive region (TAR) of the viral RNA genome. Because TAR is highly conserved and its interaction with Tat is required for efficient viral replication, it has received much attention as an antiviral drug target. Here, we report a 2-aminopurine (2-AP) fluorescence-based assay for evaluating potential TAR inhibitors. Through selective incorporation of 2-AP within the bulge (C23 or U24) of a truncated form of the TAR sequence (Δ TAR-ap23 and Δ TAR-ap24), binding of argininamide, a 24-residue arginine-rich peptide derived from Tat, and Neomycin has been characterized using steady-state fluorescence. Binding of argininamide to the 2-AP ΔTAR constructs results in a four- to 11-fold increase in fluorescence intensity, thus providing a sensitive reporter of that interaction (KD ~ 1 mM). Similarly, binding of the Tat peptide results in an initial 14-fold increase in fluorescence (KD ~ 25 nM), but is then followed by a slight decrease that is attributed to an additional, lower-affinity association(s). Using the ΔTAR-ap23 and TAR-ap24 constructs, two classes of Neomycin binding sites are detected; the first molecule of antibiotic binds as a noncompetitive inhibitor of Tat/argininamide (KD ~ 200 nM), whereas the second, more weakly bound molecule(s) becomes associated in a presumably nonspecific manner (KD ~ 4 μM). Taken together, the results demonstrate that the 2-AP fluorescence-detected binding assays provide accurate and general methods for quantitatively assessing TAR interactions. PMID:15273324

  13. Pyrolysis of aseptic packages (tetrapak) in a laboratory screw type reactor and secondary thermal/catalytic tar decomposition.

    PubMed

    Haydary, J; Susa, D; Dudáš, J

    2013-05-01

    Pyrolysis of aseptic packages (tetrapak cartons) in a laboratory apparatus using a flow screw type reactor and a secondary catalytic reactor for tar cracking was studied. The pyrolysis experiments were realized at temperatures ranging from 650 °C to 850 °C aimed at maximizing of the amount of the gas product and reducing its tar content. Distribution of tetrapak into the product yields at different conditions was obtained. The presence of H2, CO, CH4, CO2 and light hydrocarbons, HCx, in the gas product was observed. The Aluminum foil was easily separated from the solid product. The rest part of char was characterized by proximate and elemental analysis and calorimetric measurements. The total organic carbon in the tar product was estimated by elemental analysis of tars. Two types of catalysts (dolomite and red clay marked AFRC) were used for catalytic thermal tar decomposition. Three series of experiments (without catalyst in a secondary cracking reactor, with dolomite and with AFRC) at temperatures of 650, 700, 750, 800 and 850 °C were carried out. Both types of catalysts have significantly affected the content of tars and other components in pyrolytic gases. The effect of catalyst on the tetrapack distribution into the product yield on the composition of gas and on the total organic carbon in the tar product is presented in this work. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Identification of amino acids that promote specific and rigid TAR RNA-tat protein complex formation.

    PubMed

    Edwards, Thomas E; Robinson, Bruce H; Sigurdsson, Snorri Th

    2005-03-01

    The Tat protein and the transactivation responsive (TAR) RNA form an essential complex in the HIV lifecycle, and mutations in the basic region of the Tat protein alter this RNA-protein molecular recognition. Here, EPR spectroscopy was used to identify amino acids, flanking an essential arginine of the Tat protein, which contribute to specific and rigid TAR-Tat complex formation by monitoring changes in the mobility of nitroxide spin-labeled TAR RNA nucleotides upon binding. Arginine to lysine N-terminal mutations did not affect TAR RNA interfacial dynamics. In contrast, C-terminal point mutations, R56 in particular, affected the mobility of nucleotides U23 and U38, which are involved in a base-triple interaction in the complex. This report highlights the role of dynamics in specific molecular complex formation and demonstrates the ability of EPR spectroscopy to study interfacial dynamics of macromolecular complexes.

  15. Down in the Paleochannels

    NASA Image and Video Library

    2015-11-27

    This whole area, located in Solis Planum, is an interesting, tectonic terrain south of Noctis Labrynthus which generally slopes toward the south as seen by NASA Mars Reconnaissance Orbiter spacecraft. Transverse aeolian ridges -- or TAR -- are mysterious, wind-blown features that are intermediate in size between ripples and much larger sand dunes. Ripples form from hopping sand grains, and dunes form from sand grains being blown over longer distances. One hypothesis for TAR formation is that larger grains like pebbles are rolled on top of smaller ripples; then, finer dust settles into the cracks, "inflating" the pebbles, making the TAR larger than typical ripples. Looking between the TAR, one sees a network of ancient, beaten-up channels that were carved by water, lava, or both. This whole area is located in Solis Planum, an interesting, tectonic terrain south of Noctis Labrynthus which generally slopes toward the south. http://photojournal.jpl.nasa.gov/catalog/PIA20157

  16. Machine-smoking studies of cigarette filter color to estimate tar yield by visual assessment and through the use of a colorimeter.

    PubMed

    Morton, Michael J; Williams, David L; Hjorth, Heather B; Smith, Jennifer H

    2010-04-01

    This paper explores using the intensity of the stain on the end of the filter ("filter color") as a vehicle for estimating cigarette tar yield, both by instrument reading of the filter color and by visual comparison to a template. The correlation of machine-measured tar yield to filter color measured with a colorimeter was reasonably strong and was relatively unaffected by different puff volumes or different tobacco moistures. However, the correlation of filter color to machine-measured nicotine yield was affected by the moisture content of the cigarette. Filter color, as measured by a colorimeter, was generally comparable to filter extraction of either nicotine or solanesol in its correlation to machine-smoked tar yields. It was found that the color of the tar stain changes over time. Panelists could generally correctly order the filters from machine-smoked cigarettes by tar yield using the intensity of the tar stain. However, there was considerable variation in the panelist-to-panelist tar yield estimates. The wide person-to-person variation in tar yield estimates, and other factors discussed in the text could severely limit the usefulness and practicality of this approach for visually estimating the tar yield of machine-smoked cigarettes. Copyright 2009 Elsevier Inc. All rights reserved.

  17. A case-control study of asphalt and tar exposure and lung cancer in minorities.

    PubMed

    McClean, Michael D; Kelsey, Karl T; Sison, Jennette D; Quesenberry, Charles P; Wrensch, Margaret R; Wiencke, John K

    2011-11-01

    Considerable controversy surrounds the carcinogenic potential of asphalt and tar. Since minority individuals may have had relatively high historical exposures, we investigated asphalt and tar exposure and lung cancer risk among African Americans and Latino Americans. We conducted a case-control study of lung cancer among African Americans and Latino Americans in the San Francisco Bay area (422 cases, 894 controls). A questionnaire was used to obtain detailed work histories and exposure information. Self-reported exposure to asphalt and tar as well as other factors (e.g., smoking, automobile exhaust, and asbestos) were evaluated as predictors of lung cancer risk. Potential effect modification by cytochrome P450 (CYP) 1A1 was also explored. Self-reported duration of exposure to asphalt and tar was associated with a statistically significant excess risk of lung cancer in the overall population (OR: 1.11, 95% CI: 1.01-1.22), evaluating risk per year of exposure. Years of exposure to automobile exhaust (OR: 1.02, 95% CI: 1.00-1.05) and asbestos (OR: 1.04, 95% CI: 1.02-1.06) were also associated with statistically significant elevations in risk. In Latino Americans, the lung cancer risks associated with polycyclic aromatic hydrocarbon-related exposures were consistently higher in the CYP1A1 wild-type subjects as compared to the variant genotype subjects, and the interaction was statistically significant for smoking and the CYP1A1 M2 polymorphism (P-value(interaction) = 0.02). These data are consistent with the literature suggesting that exposure to asphalt and tar may increase risk of lung cancer. However, it was not possible to separate the effects and asphalt and tar in this study. Copyright © 2011 Wiley Periodicals, Inc.

  18. A Case-Control Study of Asphalt and Tar Exposure and Lung Cancer in Minorities

    PubMed Central

    McClean, Michael D.; Kelsey, Karl T.; Sison, Jennette D; Quesenberry, Charles P; Wrensch, Margaret R; Wiencke, John K.

    2011-01-01

    Objectives Considerable controversy surrounds the carcinogenic potential of asphalt and tar. Since minority individuals may have had relatively high historical exposures, we investigated asphalt and tar exposure and lung cancer risk among African Americans and Latino Americans. Methods We conducted a case-control study of lung cancer among African Americans and Latino Americans in the San Francisco Bay area (422 cases, 894 controls). A questionnaire was used to obtain detailed work histories and exposure information. Self-reported exposure to asphalt and tar as well as other factors (eg. smoking, automobile exhaust, and asbestos) were evaluated as predictors of lung cancer risk. Potential effect modification by cytochrome P450 (CYP) 1A1 was also explored. Results Self-reported duration of exposure to asphalt and tar was associated with a statistically significant excess risk of lung cancer in the overall population (OR: 1.11, 95%CI: 1.01–1.22), evaluating risk per year of exposure. Years of exposure to automobile exhaust (OR: 1.02, 95%CI: 1.00–1.05) and asbestos (OR: 1.04, 95%CI: 1.02–1.06) were also associated with statistically significant elevations in risk. In Latino Americans, the lung cancer risks associated with polycyclic aromatic hydrocarbon-related exposures were consistently higher in the CYP1A1 wildtype subjects as compared to the variant genotype subjects, and the interaction was statistically significant for smoking and the CYP1A1 M2 polymorphism (p-valueinteraction=0.02). Conclusions These data are consistent with the literature suggesting that exposure to asphalt and tar may increase risk of lung cancer. However, it was not possible to separate the effects and asphalt and tar in this study. PMID:21882217

  19. Injection-site vein loss and soft tissue abscesses associated with black tar heroin injection: A cross-sectional study of two distinct populations in USA.

    PubMed

    Summers, Phillip J; Struve, Isabelle A; Wilkes, Michael S; Rees, Vaughan W

    2017-01-01

    Injection-site vein loss and skin abscesses impose significant morbidity on people who inject drugs (PWID). The two common forms of street heroin available in the USA include black tar and powder heroin. Little research has investigated these different forms of heroin and their potential implications for health outcomes. A multiple-choice survey was administered to a sample of 145 participants seeking services at reduction facilities in both Sacramento, CA and greater Boston, MA, USA. Multivariate regression models for reporting one or more abscesses in one year, injection-site veins lost in six months, and soft tissue injection. Participants in Sacramento exclusively used black tar (99%), while those in Boston used powder heroin (96%). Those who used black tar heroin lost more injection-site veins (β=2.34, 95% CI: 0.66-4.03) and were more likely to report abscesses (AOR=7.68, 95% CI: 3.01-19.60). Soft tissue injection was also associated with abscesses (AOR=4.68, 95% CI: 1.84-11.93). Consistent venous access (AOR: 0.088, 95% CI: 0.011-0.74) and losing more injection sites (AOR: 1.22, 95% CI: 1.03-1.45) were associated with soft tissue injection. Use of black tar heroin is associated with more frequent abscesses and more extensive vein loss. Poor venous access predisposes people who inject drugs to soft tissue injection, which may constitute a causal pathway between black tar heroin injection and abscess formation. The mechanisms by which black tar heroin contributes to vein loss and abscess formation must be further elucidated in order to develop actionable interventions for maintaining vein health and decreasing the abscess burden. Potential interventions include increased access to clean injection equipment and education, supervised injection facilities, opioid substitution therapy, and supply chain interventions targeting cutting agents. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. The linear relationship between cigarette tar and nicotine yields: regulatory implications for smoke constituent ratios.

    PubMed

    St Charles, F K; Cook, C J; Clayton, P M

    2011-02-01

    Cigarette smoke analyte yields are often expressed as ratios relative to tar or nicotine yields, usually to compare different products or to estimate human uptake of smoke in relation to nicotine uptake measurements. The method, however, can lead to distorted interpretations, especially in the case of ratios from ultra-low tar yield cigarettes. In brief, as tar yields decrease below the 5–6 mg per cigarette range, the tar-to-nicotine ratio (TNR) decreases rapidly in a non-linear fashion. If, however, the nicotine yield, rather than the ratio, is plotted versus the tar yield, the non-linearity disappears and a straight line is obtained, with a slight positive intercept for nicotine on the ordinate. Unlike the ratio, the slope appears to depend only on the concentration of the nicotine in the blend and does not appear to vary with smoking parameters such as puff volume, puff interval or length smoked or with cigarette design parameters such as length, circumference or the amount of filtration or filter ventilation. Therefore, such a slope is analogous to the TNR although, unlike that ratio, it is invariant. Even more simply, the concentration of the nicotine in the blend, at least for American blend-style cigarettes, provides a similar index.

  1. Design-Based Peptidomimetic Ligand Discovery to Target HIV TAR RNA Using Comparative Analysis of Different Docking Methods.

    PubMed

    Fu, Junjie; Xia, Amy; Dai, Yao; Qi, Xin

    2016-01-01

    Discovering molecules capable of binding to HIV trans-activation responsive region (TAR) RNA thereby disrupting its interaction with Tat protein is an attractive strategy for developing novel antiviral drugs. Computational docking is considered as a useful tool for predicting binding affinity and conducting virtual screening. Although great progress in predicting protein-ligand interactions has been achieved in the past few decades, modeling RNA-ligand interactions is still largely unexplored due to the highly flexible nature of RNA. In this work, we performed molecular docking study with HIV TAR RNA using previously identified cyclic peptide L22 and its analogues with varying affinities toward HIV-1 TAR RNA. Furthermore, sarcosine scan was conducted to generate derivatives of CGP64222, a peptide-peptoid hybrid with inhibitory activity on Tat/TAR RNA interaction. Each compound was docked using CDOCKER, Surflex-Dock and FlexiDock to compare the effectiveness of each method. It was found that FlexiDock energy values correlated well with the experimental Kd values and could be used to predict the affinity of the ligands toward HIV-1 TAR RNA with a superior accuracy. Our results based on comparative analysis of different docking methods in RNA-ligand modeling will facilitate the structure-based discovery of HIV TAR RNA ligands for antiviral therapy.

  2. Identification of sources of tar balls deposited along the Goa coast, India, using fingerprinting techniques.

    PubMed

    Suneel, V; Vethamony, P; Zakaria, M P; Naik, B G; Prasad, K V S R

    2013-05-15

    Deposition of tar balls along the coast of Goa, India is a common phenomenon during the southwest monsoon. Representative tar ball samples collected from various beaches of Goa and one Bombay High (BH) crude oil sample were subjected to fingerprint analysis based on diagnostic ratios of n-alkane, biomarkers of pentacyclic tri-terpanes and compound specific stable carbon isotope (δ¹³C) analysis to confirm the source. The results were compared with the published data of Middle East Crude Oil (MECO) and South East Asian Crude Oil (SEACO). The results revealed that the tar balls were from tanker-wash derived spills. The study also confirmed that the source is not the BH, but SEACO. The present study suggests that the biomarkers of alkanes and hopanes coupled with stable carbon isotope analysis act as a powerful tool for tracing the source of tar balls, particularly when the source specific biomarkers fail to distinguish the source. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Coupled changes in sand grain size and sand transport driven by changes in the upstream supply of sand in the Colorado River: relative importance of changes in bed-sand grain size and bed-sand area

    USGS Publications Warehouse

    Topping, D.J.; Rubin, D.M.; Melis, T.S.

    2007-01-01

    Sand transport in the Colorado River in Marble and Grand canyons was naturally limited by the upstream supply of sand. Prior to the 1963 closure of Glen Canyon Dam, the river exhibited the following four effects of sand supply limitation: (1) hysteresis in sediment concentration, (2) hysteresis in sediment grain size coupled to the hysteresis in sediment concentration, (3) production of inversely graded flood deposits, and (4) development or modification of a lag between the time of a flood peak and the time of either maximum or minimum (depending on reach geometry) bed elevation. Construction and operation of the dam has enhanced the degree to which the first two of these four effects are evident, and has not affected the degree to which the last two effects of sand supply limitation are evident in the Colorado River in Marble and Grand canyons. The first three of the effects involve coupled changes in suspended-sand concentration and grain size that are controlled by changes in the upstream supply of sand. During tributary floods, sand on the bed of the Colorado River fines; this causes the suspended sand to fine and the suspended-sand concentration to increase, even when the discharge of water remains constant. Subsequently, the bed is winnowed of finer sand, the suspended sand coarsens, and the suspended-sand concentration decreases independently of discharge. Also associated with these changes in sand supply are changes in the fraction of the bed that is covered by sand. Thus, suspended-sand concentration in the Colorado River is likely regulated by both changes in the bed-sand grain size and changes in the bed-sand area. A physically based flow and suspended-sediment transport model is developed, tested, and applied to data from the Colorado River to evaluate the relative importance of changes in the bed-sand grain size and changes in the bed-sand area in regulating suspended-sand concentration. Although the model was developed using approximations for steady

  4. Ubiquitous tar balls with a California-source signature on the shorelines of Prince William Sound, Alaska

    USGS Publications Warehouse

    Kvenvolden, K.A.; Hostettler, F.D.; Carlson, P.R.; Rapp, J.B.; Threlkeld, C.N.; Warden, A.

    1995-01-01

    Although the shorelines of Prince William Sound still bear traces of the 1989 Exxon Valdez oil spill, most of the flattened tar balls that can be found today on these shorelines are not residues of Exxon Valdez oil. Instead, the carbon-isotopic and hydrocarbon-biomarker signatures of 61 tar ball samples, collected from shorelines throughout the northern and western parts of the sound, are all remarkably similar and have characteristics consistent with those of oil products that originated from the Monterey Formation source rocks of California. The carbon-isotopic compositions of the tar balls are all closely grouped (??13CPDB = -23.7 ?? 0.2???), within the range found in crude oils from those rocks, but are distinct from isotopic compositions of 28 samples of residues from the Exxon Valdez oil spill (??13CPDB = -29.4 ?? 0.1???). Likewise, values for selected biomarker ratios in the tar balls are all similar but distinct from values of residues from the 1989 oil spill. Carbon-isotopic and biomarker signatures generally relate the tar balls to oil products used in Alaska before ???1970 for construction and pavements. How these tar balls with such similar geochemical characteristics became so widely dispersed throughout the northern and western parts of the sound is not known with certainty, but the great 1964 Alaska earthquake was undoubtedly an important trigger, causing spills from ruptured storage facilities of California-sourced asphalt and fuel oil into Prince William Sound.

  5. Microplastic and tar pollution on three Canary Islands beaches: An annual study.

    PubMed

    Herrera, A; Asensio, M; Martínez, I; Santana, A; Packard, T; Gómez, M

    2018-04-01

    Marine debris accumulation was analyzed from three exposed beaches of the Canary Islands (Lambra, Famara and Las Canteras). Large microplastics (1-5mm), mesoplastics (5-25mm) and tar pollution were assessed twice a month for a year. There was great spatial and temporal variability in the Canary Island coastal pollution. Seasonal patterns differed at each location, marine debris concentration depended mainly of local-scale wind and wave conditions. The most polluted beach was Lambra, a remote beach infrequently visited. The types of debris found were mainly preproduction resin pellets, plastic fragments and tar, evidencing that pollution was not of local origin, but it cames from the open sea. The levels of pollution were similar to those of highly industrialized and contaminated regions. This study corroborates that the Canary Islands are an area of accumulation of microplastics and tar rafted from the North Atlantic Ocean by the southward flowing Canary Current. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Numerical simulation of vortex pyrolysis reactors for condensable tar production from biomass

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miller, R.S.; Bellan, J.

    1998-08-01

    A numerical study is performed in order to evaluate the performance and optimal operating conditions of vortex pyrolysis reactors used for condensable tar production from biomass. A detailed mathematical model of porous biomass particle pyrolysis is coupled with a compressible Reynolds stress transport model for the turbulent reactor swirling flow. An initial evaluation of particle dimensionality effects is made through comparisons of single- (1D) and multi-dimensional particle simulations and reveals that the 1D particle model results in conservative estimates for total pyrolysis conversion times and tar collection. The observed deviations are due predominantly to geometry effects while directional effects frommore » thermal conductivity and permeability variations are relatively small. Rapid ablative particle heating rates are attributed to a mechanical fragmentation of the biomass particles that is modeled using a critical porosity for matrix breakup. Optimal thermal conditions for tar production are observed for 900 K. Effects of biomass identity, particle size distribution, and reactor geometry and scale are discussed.« less

  7. Understanding the fate and transport of petroleum hydrocarbons from coal tar within gasholders.

    PubMed

    Coulon, Frédéric; Orsi, Roberto; Turner, Claire; Walton, Chris; Daly, Paddy; Pollard, Simon J T

    2009-02-01

    Coal tars have been identified as posing a threat to human health due to their toxic, mutagenic and carcinogenic characteristics. Workers involved in former gasholders decommissioning are potentially exposed to relevant concentrations of volatile and semi-volatile hydrocarbons upon opening up derelict tanks and during tar excavation/removal. While information on contaminated sites air-quality and its implications on medium-long term exposure is available, acute exposure issues associated with the execution of critical tasks are less understood. Calculations indicated that the concentration of a given contaminant in the gasholder vapour phase only depends on the coal tar composition, being only barely affected by the presence of water in the gasholder and the tar volume/void space ratio. Fugacity modelling suggested that risk-critical compounds such as benzene, naphthalene and other monocyclic and polycyclic aromatic hydrocarbons may gather in the gasholder air phase at significant concentrations. Gasholder emissions were measured on-site and compared with the workplace exposure limits (WELs) currently in use in UK. While levels for most of the toxic compounds were far lower than WELs, benzene air-concentrations where found to be above the accepted threshold. In addition due to the long exposure periods involved in gasholder decommissioning and the significant contribution given by naphthalene to the total coal tar vapour concentration, the adoption of a WEL for naphthalene may need to be considered to support operators in preventing human health risk at the workplace. The Level I fugacity approach used in this study demonstrated its suitability for applications to sealed environments such as gasholders and its further refining could provide a useful tool for land remediation risk assessors.

  8. Sand Volcano Following Earthquake

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Sand boil or sand volcano measuring 2 m (6.6 ft.) in length erupted in median of Interstate Highway 80 west of the Bay Bridge toll plaza when ground shaking transformed loose water-saturated deposit of subsurface sand into a sand-water slurry (liquefaction) in the October 17, 1989, Loma Prieta earthquake. Vented sand contains marine-shell fragments. Sand and soil grains have faces that can cause friction as they roll and slide against each other, or even cause sticking and form small voids between grains. This complex behavior can cause soil to behave like a liquid under certain conditions such as earthquakes or when powders are handled in industrial processes. Mechanics of Granular Materials (MGM) experiments aboard the Space Shuttle use the microgravity of space to simulate this behavior under conditions that carnot be achieved in laboratory tests on Earth. MGM is shedding light on the behavior of fine-grain materials under low effective stresses. Applications include earthquake engineering, granular flow technologies (such as powder feed systems for pharmaceuticals and fertilizers), and terrestrial and planetary geology. Nine MGM specimens have flown on two Space Shuttle flights. Another three are scheduled to fly on STS-107. The principal investigator is Stein Sture of the University of Colorado at Boulder. (Credit: J.C. Tinsley, U.S. Geological Survey)

  9. Faecal indicator bacteria enumeration in beach sand: a comparison study of extraction methods in medium to coarse sands.

    PubMed

    Boehm, A B; Griffith, J; McGee, C; Edge, T A; Solo-Gabriele, H M; Whitman, R; Cao, Y; Getrich, M; Jay, J A; Ferguson, D; Goodwin, K D; Lee, C M; Madison, M; Weisberg, S B

    2009-11-01

    The absence of standardized methods for quantifying faecal indicator bacteria (FIB) in sand hinders comparison of results across studies. The purpose of the study was to compare methods for extraction of faecal bacteria from sands and recommend a standardized extraction technique. Twenty-two methods of extracting enterococci and Escherichia coli from sand were evaluated, including multiple permutations of hand shaking, mechanical shaking, blending, sonication, number of rinses, settling time, eluant-to-sand ratio, eluant composition, prefiltration and type of decantation. Tests were performed on sands from California, Florida and Lake Michigan. Most extraction parameters did not significantly affect bacterial enumeration. anova revealed significant effects of eluant composition and blending; with both sodium metaphosphate buffer and blending producing reduced counts. The simplest extraction method that produced the highest FIB recoveries consisted of 2 min of hand shaking in phosphate-buffered saline or deionized water, a 30-s settling time, one-rinse step and a 10 : 1 eluant volume to sand weight ratio. This result was consistent across the sand compositions tested in this study but could vary for other sand types. Method standardization will improve the understanding of how sands affect surface water quality.

  10. Ripples and Dunes in Proctor Crater

    NASA Image and Video Library

    2017-10-09

    NASA's Mars Reconnaissance Rover (MRO) has observed two types of wind (aeolian) features in Proctor Crater: large, dark features that are sand dunes, made up of basaltic particles, and smaller, light-toned ripples that we call "TAR," or "transverse aeolian ridges." The origin of the TARs is a mystery. They might be dust deposits, or perhaps coarse grained ripples that are coated in bright dust. These TARs are less than 10 meters tall, and are much smaller than the sand dunes that reach impressive heights of over 130 meters. In other places on Mars, TARs are generally older than sand dunes, but here in Proctor Crater, it is not so obvious. How can we tell which came first, the TARs or the dunes? The dunes are situated on top of the TARs, and with this information, we can say the dunes are clearly the younger formations here in Proctor Crater. Fortunately, HiRISE has a tool that can solve this riddle. By taking stereo images of the same region from two different locations, we can estimate the topography of the region by measuring the displacement of surface features from one picture to the other. The result is a quantitative estimate of the local surface topography, called a digital terrain model. The dunes are situated on top of the TARs, and with this information, we can say the dunes are clearly the younger formations here in Proctor Crater. https://photojournal.jpl.nasa.gov/catalog/PIA22040

  11. Evaluation of Durability Parameters of Concrete with Manufacture Sand and River Sand

    NASA Astrophysics Data System (ADS)

    Sangoju, Bhaskar; Ramesh, G.; Bharatkumar, B. H.; Ramanjaneyulu, K.

    2017-09-01

    Most of the states in our country have banned sand quarrying from the river beds, causing a scarcity of natural river sand for the construction sector. Manufacture sand (M-sand) is one of the alternate solutions to replace the river sand (R-sand) in concrete. The main aim of the present study is to evaluate the durability parameters of concrete with M-sand when compared to that of concrete with R-sand. Corrosion of reinforcement is one of the main deteriorating mechanisms of reinforced concrete due to the ingress of chloride ions or carbon-di-oxide. For comparative evaluation of durability parameters, accelerated tests such as Rapid Chloride Permeability Test, Rapid Chloride Migration Test and accelerated carbonation test were carried out on specimens of R-sand and M-sand. All tests were carried out after 90 days of casting. Test results reveal that the durability parameters of the concrete with M-sand in chloride induced environment is relatively better than that of concrete with R-sand and hence is recommended to use M-sand as a replacement to R-sand.

  12. Adverse effects of inhaled sand dust particles on the respiratory organs of sheep and goats exposed to severe sand storms in Mongolia.

    PubMed

    Kobayashi, Yoshimi; Shimada, Akinori; Nemoto, Mai; Morita, Takehito; Adilbish, Altanchimeg; Bayasgalan, Mungun-Ochir

    2014-01-01

    Sand storms in Mongolia have increased in frequency and scale, resulting in increased exposure of the inhabitants of Asian countries, including Japan and Korea, to Asian sand dust (ASD), which results in adverse effects on the respiratory system. However, there is no information on the health risks of severe sand storms in domestic animals in Mongolia. The aim of the study was to investigate the effects of sand dust particles on the respiratory organs, including the lungs and tracheobronchial lymph nodes, of sheep and goats exposed to severe sand storms in Mongolia. Seven adult sheep and 4 adult goats that had been exposed to sand storms and 3 sheep with no history of exposure were included in this study. Lung tissues and tracheobronchial lymph nodes were subjected to histopathological and immunohistochemical examination. The mineralogical contents of the lungs and lymph nodes were determined using inductively coupled plasma atomic emission spectroscopy. Fibrosis and granulomatous lesions comprising macrophages containing fine sand dust particles were observed exclusively in the lungs of sheep and goats exposed to sand storms. The activity of macrophages was also demonstrated by the presence of IL-6, TNF, and lysozyme. In addition, silicon, which is the major element of ASD (kosa aerosol), was detected exclusively in the lung tissues of the exposed animals. Our findings suggest that exposure to sand dust particles may affect the respiratory systems of domestic animals during their relatively short life span.

  13. Upgrading producer gas quality from rubber wood gasification in a radio frequency tar thermocatalytic treatment reactor.

    PubMed

    Anis, Samsudin; Zainal, Z A

    2013-12-01

    This study focused on improving the producer gas quality using radio frequency (RF) tar thermocatalytic treatment reactor. The producer gas containing tar, particles and water was directly passed at a particular flow rate into the RF reactor at various temperatures for catalytic and thermal treatments. Thermal treatment generates higher heating value of 5.76 MJ Nm(-3) at 1200°C. Catalytic treatments using both dolomite and Y-zeolite provide high tar and particles conversion efficiencies of about 97% on average. The result also showed that light poly-aromatic hydrocarbons especially naphthalene and aromatic compounds particularly benzene and toluene were still found even at higher reaction temperatures. Low energy intensive RF tar thermocatalytic treatment was found to be effective for upgrading the producer gas quality to meet the end user requirements and increasing its energy content. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Determination of the conformational ensemble of the TAR RNA by X-ray scattering interferometry

    PubMed Central

    Walker, Peter

    2017-01-01

    Abstract The conformational ensembles of structured RNA's are crucial for biological function, but they remain difficult to elucidate experimentally. We demonstrate with HIV-1 TAR RNA that X-ray scattering interferometry (XSI) can be used to determine RNA conformational ensembles. X-ray scattering interferometry (XSI) is based on site-specifically labeling RNA with pairs of heavy atom probes, and precisely measuring the distribution of inter-probe distances that arise from a heterogeneous mixture of RNA solution structures. We show that the XSI-based model of the TAR RNA ensemble closely resembles an independent model derived from NMR-RDC data. Further, we show how the TAR RNA ensemble changes shape at different salt concentrations. Finally, we demonstrate that a single hybrid model of the TAR RNA ensemble simultaneously fits both the XSI and NMR-RDC data set and show that XSI can be combined with NMR-RDC to further improve the quality of the determined ensemble. The results suggest that XSI-RNA will be a powerful approach for characterizing the solution conformational ensembles of RNAs and RNA-protein complexes under diverse solution conditions. PMID:28108663

  15. Determination of the conformational ensemble of the TAR RNA by X-ray scattering interferometry.

    PubMed

    Shi, Xuesong; Walker, Peter; Harbury, Pehr B; Herschlag, Daniel

    2017-05-05

    The conformational ensembles of structured RNA's are crucial for biological function, but they remain difficult to elucidate experimentally. We demonstrate with HIV-1 TAR RNA that X-ray scattering interferometry (XSI) can be used to determine RNA conformational ensembles. X-ray scattering interferometry (XSI) is based on site-specifically labeling RNA with pairs of heavy atom probes, and precisely measuring the distribution of inter-probe distances that arise from a heterogeneous mixture of RNA solution structures. We show that the XSI-based model of the TAR RNA ensemble closely resembles an independent model derived from NMR-RDC data. Further, we show how the TAR RNA ensemble changes shape at different salt concentrations. Finally, we demonstrate that a single hybrid model of the TAR RNA ensemble simultaneously fits both the XSI and NMR-RDC data set and show that XSI can be combined with NMR-RDC to further improve the quality of the determined ensemble. The results suggest that XSI-RNA will be a powerful approach for characterizing the solution conformational ensembles of RNAs and RNA-protein complexes under diverse solution conditions. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  16. Superfund Record of Decision (EPA Region 5): Reilly Tar and Chemical Corporation Site, St. Peter Aquifer, St. Louis Park, MN. (Third remedial action), September 1990

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1990-09-28

    The 80-acre Reilly Tar and Chemical (St. Louis Park) site is a former coal tar distillation and wood preserving plant in St. Louis Park, Minnesota. The site overlies a complex system of aquifers, including the St. Peter aquifer that provide drinking water to area residences. The St. Peter Aquifer contains one municipal well, which is used during periods of peak demand, however, the majority of the drinking water in St. Louis Park is obtained from deeper aquifers. From 1917 to 1972, wastewater containing creosote and coal tar was discharged to onsite surface water, and as a result, small wastewater spillsmore » occurred into onsite soil. The ROD addresses Operable Unit 4 (OU4), remediation of the St. Peter aquifer. A subsequent ROD will address any remaining site problems as OU3. The primary contaminants of concern affecting the ground water are organics including PAHs and phenols.« less

  17. Sand transportation and reverse patterns over leeward face of sand dune

    NASA Astrophysics Data System (ADS)

    Jiang, Hong; Dun, Hongchao; Tong, Ding; Huang, Ning

    2017-04-01

    Sand saltation has complex interactions with turbulent flow and dune form. Most models of wind-blown sand consider ideal circumstances such as steady wind velocity and a flat surface, and the bulk of data on wind flow and sand transport over an individual dune has focused mostly on the influence of dune shape or inter-dune space on the wind flow, neglecting the effect of morphology on sand saltation, particularly airflow and sand transportation over the leeward slope. Wind flow structures over the leeward slope of sand dunes have a fundamental influence on the organization of sand dunes. In order to understand sand dune dynamics, lee face airflow and sediment transportation should be paid more attention. Previous field observations could not measure turbulent flow structure well because of the limited observation points and the influence of experiment structure on wind field. In addition, the reverse sand particles over leeward face could not be collected by sand trap in field. Numerous field observations could not measure turbulent flow structure because of the limited observation points and the influence of experimental structures on the wind field. In addition, the reverse transport of sand particles over leeward face could not be collected by sand traps in field. Therefore, this paper aims to investigate the turbulent flow structure and sand transport pattern over the leeward slope. A numerical model of sand saltation over slope terrain is constructed, which also considers the coupling effects between air flow and sand particles. The large eddy simulation method is used to model turbulent flow. Sand transport is simulated by tracking the trajectory of each sand particle. The results show that terrain significantly alters the turbulent air flow structure and wind-blown sand movement, especially over the leeward slope. Here, mass flux increases initially and then decreases with height in the reversed flow region in the direction of wind flow, and the mass flux

  18. SULFUR TOLERANT CATALYSTS FOR BIOMASS TAR REMOVAL - PHASE I

    EPA Science Inventory

    In this Small Business Innovation Research (SBIR) project, NexTech Materials proposes a catalytic reforming approach to remove waste tar from gasified biomass on nickel-based catalysts. Biomass gasification is a potential renewable route to producing electricity, liquid fue...

  19. Sand dune tracking from satellite laser altimetry

    NASA Astrophysics Data System (ADS)

    Dabboor, Mohammed

    Substantial problems arise from sand movement in arid and semi-arid countries. Sand poses a threat to infrastructure, agricultural and urban areas. These issues are caused by the encroachment of sand on roads and railway tracks, farmland, towns and villages, and airports, to name a few. Sand movement highly depends on geomorphology including vegetation cover, shape and height of the terrain, and grain size of the sand. However, wind direction and speed are the most important factors that affect efficient sand movement. The direction of the movement depends on the main direction of the wind, but it has been shown that a minimum wind speed is required, e.g. wind gusts, to initiate sand transport. This fact prevents a simple calculation of sand transport from conventional wind data as wind records rarely contain sub-minute intervals masking out any wind gusts. An alternative of predicting sand transport is the direct observation of sand advance by in situ measurements or via satellite. Until recently, satellite imagery was the only means to compare dune shape and position for predicting dune migration over several years. In 2003, the NASA laser altimetry mission ICESat became operational and monitors elevations over all surface types including sand dunes with an accuracy of about 10-20 cm. In this study, ICESat observations from repeat tracks (tracks overlapping eachother within 50 m) are used to derive sand dune advance and direction. The method employs a correlation of the elevation profiles over several dunes and was sucessfully validated with synthetic data. The accuracy of this method is 5 meters of dune advance. One of the most active areas exhibiting sand and dune movement is the area of the Arabian Peninsula. Approximately one-third of the Arabian Peninsula is covered by sand dunes. Different wind regimes (Shamal, Kaus) cause sand dune movement in the selected study area in the eastern part of the Arabian Peninsula between 20-25 degrees North and 45-55 degrees

  20. Carbon starvation in glacial trees recovered from the La Brea tar pits, southern California

    Treesearch

    Joy K. Ward; John M. Harris; Thure E. Cerling; Alex Wiedenhoeft; Michael J. Lott; Maria-Denise Dearing; Joan B. Coltrain; James R. Ehleringer

    2005-01-01

    The Rancho La Brea tar pit fossil collection includes Juniperus (C3) wood specimens that 14C date between 7.7 and 55 thousand years (kyr) B.P., providing a constrained record of plant response for southern California during the last glacial period. Atmospheric CO2 concentration ([CO2]) ranged between 180 and 220 ppm during glacial periods, rose to 280 ppm before the...

  1. Insights into the sand fly saliva: Blood-feeding and immune interactions between sand flies, hosts, and Leishmania.

    PubMed

    Lestinova, Tereza; Rohousova, Iva; Sima, Michal; de Oliveira, Camila I; Volf, Petr

    2017-07-01

    Leishmaniases are parasitic diseases present worldwide that are transmitted to the vertebrate host by the bite of an infected sand fly during a blood feeding. Phlebotomine sand flies inoculate into the mammalian host Leishmania parasites embedded in promastigote secretory gel (PSG) with saliva, which is composed of a diverse group of molecules with pharmacological and immunomodulatory properties. In this review, we focus on 3 main aspects of sand fly salivary molecules: (1) structure and composition of salivary glands, including the properties of salivary molecules related to hemostasis and blood feeding, (2) immunomodulatory properties of salivary molecules and the diverse impacts of these molecules on leishmaniasis, ranging from disease exacerbation to vaccine development, and (3) use of salivary molecules for field applications, including monitoring host exposure to sand flies and the risk of Leishmania transmission. Studies showed interesting differences between salivary proteins of Phlebotomus and Lutzomyia species, however, no data were ever published on salivary proteins of Sergentomyia species. In the last 15 years, numerous studies have characterized sand fly salivary proteins and, in parallel, have addressed the impact of such molecules on the biology of the host-sand fly-parasite interaction. The results obtained shall pave the way for the development of field-application tools that could contribute to the management of leishmaniasis in endemic areas.

  2. Faecal indicator bacteria enumeration in beach sand: A comparison study of extraction methods in medium to coarse sands

    USGS Publications Warehouse

    Boehm, A.B.; Griffith, J.; McGee, C.; Edge, T.A.; Solo-Gabriele, H. M.; Whitman, R.; Cao, Y.; Getrich, M.; Jay, J.A.; Ferguson, D.; Goodwin, K.D.; Lee, C.M.; Madison, M.; Weisberg, S.B.

    2009-01-01

    Aims: The absence of standardized methods for quantifying faecal indicator bacteria (FIB) in sand hinders comparison of results across studies. The purpose of the study was to compare methods for extraction of faecal bacteria from sands and recommend a standardized extraction technique. Methods and Results: Twenty-two methods of extracting enterococci and Escherichia coli from sand were evaluated, including multiple permutations of hand shaking, mechanical shaking, blending, sonication, number of rinses, settling time, eluant-to-sand ratio, eluant composition, prefiltration and type of decantation. Tests were performed on sands from California, Florida and Lake Michigan. Most extraction parameters did not significantly affect bacterial enumeration. anova revealed significant effects of eluant composition and blending; with both sodium metaphosphate buffer and blending producing reduced counts. Conclusions: The simplest extraction method that produced the highest FIB recoveries consisted of 2 min of hand shaking in phosphate-buffered saline or deionized water, a 30-s settling time, one-rinse step and a 10 : 1 eluant volume to sand weight ratio. This result was consistent across the sand compositions tested in this study but could vary for other sand types. Significance and Impact of the Study: Method standardization will improve the understanding of how sands affect surface water quality. ?? 2009 The Society for Applied Microbiology.

  3. 33 CFR 165.927 - Safety Zone; St. Louis River, Duluth/Interlake Tar Remediation Site, Duluth, MN.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety Zone; St. Louis River, Duluth/Interlake Tar Remediation Site, Duluth, MN. 165.927 Section 165.927 Navigation and Navigable... Coast Guard District § 165.927 Safety Zone; St. Louis River, Duluth/Interlake Tar Remediation Site...

  4. DIANA-TarBase v7.0: indexing more than half a million experimentally supported miRNA:mRNA interactions.

    PubMed

    Vlachos, Ioannis S; Paraskevopoulou, Maria D; Karagkouni, Dimitra; Georgakilas, Georgios; Vergoulis, Thanasis; Kanellos, Ilias; Anastasopoulos, Ioannis-Laertis; Maniou, Sofia; Karathanou, Konstantina; Kalfakakou, Despina; Fevgas, Athanasios; Dalamagas, Theodore; Hatzigeorgiou, Artemis G

    2015-01-01

    microRNAs (miRNAs) are short non-coding RNA species, which act as potent gene expression regulators. Accurate identification of miRNA targets is crucial to understanding their function. Currently, hundreds of thousands of miRNA:gene interactions have been experimentally identified. However, this wealth of information is fragmented and hidden in thousands of manuscripts and raw next-generation sequencing data sets. DIANA-TarBase was initially released in 2006 and it was the first database aiming to catalog published experimentally validated miRNA:gene interactions. DIANA-TarBase v7.0 (http://www.microrna.gr/tarbase) aims to provide for the first time hundreds of thousands of high-quality manually curated experimentally validated miRNA:gene interactions, enhanced with detailed meta-data. DIANA-TarBase v7.0 enables users to easily identify positive or negative experimental results, the utilized experimental methodology, experimental conditions including cell/tissue type and treatment. The new interface provides also advanced information ranging from the binding site location, as identified experimentally as well as in silico, to the primer sequences used for cloning experiments. More than half a million miRNA:gene interactions have been curated from published experiments on 356 different cell types from 24 species, corresponding to 9- to 250-fold more entries than any other relevant database. DIANA-TarBase v7.0 is freely available. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  5. PAH volatilization following application of coal-tar-based pavement sealant

    USGS Publications Warehouse

    Van Metre, Peter C.; Majewski, Michael S.; Mahler, Barbara J.; Foreman, William T.; Braun, Christopher L.; Wilson, Jennifer T.; Burbank, Teresa L.

    2012-01-01

    Coal-tar-based pavement sealants, a major source of PAHs to urban water bodies, have recently been identified as a source of volatile PAHs to the atmosphere. We tracked the volatilization of PAHs for 1 year after application of a coal-tar-based pavement sealant by measuring gas-phase PAH concentrations above the pavement surface and solid-phase PAH concentrations in sealant scraped from the surface. Gas-phase concentrations at two heights (0.03 and 1.28 m) and wind speed were used to estimate volatilization flux. The sum of the concentrations of eight frequently detected PAHs (ΣPAH8) in the 0.03-m sample 1.6 h after application (297,000 ng m-3) was about 5000 times greater than that previously reported for the same height above unsealed parking lots (66 ng m-3). Flux at 1.6 h after application was estimated at 45,000 μg m-2 h-1 and decreased rapidly during the 45 days after application to 160 μg m-2 h-1. Loss of PAHs from the adhered sealant also was rapid, with about a 50% decrease in solid-phase ΣPAH8 concentration over the 45 days after application. There was general agreement, given the uncertainties, in the estimated mass of ΣPAH8 lost to the atmosphere on the basis of air sampling (2–3 g m-2) and adhered sealant sampling (6 g m-2) during the first 16 days after application, translating to a loss to the atmosphere of one-quarter to one-half of the PAHs in the sealcoat product. Combining the estimated mass of ΣPAH8 released to the atmosphere with a national-use estimate of coal-tar-based sealant suggests that PAH emissions from new coal-tar-based sealcoat applications each year (~1000 Mg) are larger than annual vehicle emissions of PAHs for the United States.

  6. Developing technologies for synthetic fuels

    NASA Astrophysics Data System (ADS)

    Sprow, F. B.

    1981-05-01

    After consideration of a likely timetable for the development of a synthetic fuels industry and its necessary supporting technology, the large variety of such fuels and their potential roles is assessed along with their commercialization outlook. Among the fuel production methods considered are: (1) above-ground retorting of oil shale; (2) in-situ shale retorting; (3) open pit mining of tar sands; (4) in-situ steam stimulation of tar sands; (5) coal gasification; (6) methanol synthesis from carbon monoxide and hydrogen; and (7) direct coal liquefaction by the hydrogenation of coal. It is shown that while the U.S. has very limited resource bases for tar sands and heavy crudes, the abundance of shale in the western states and the abundance and greater geographical dispersion of coal will make these the two most important resources of a future synthetic fuels industry.

  7. A randomized, investigator-masked clinical evaluation of the efficacy and safety of clobetasol propionate 0.05% shampoo and tar blend 1% shampoo in the treatment of moderate to severe scalp psoriasis.

    PubMed

    Griffiths, Christopher E M; Finlay, Andrew Y; Fleming, Colin J; Barker, Jonathan N W N; Mizzi, Fabienne; Arsonnaud, Stéphanie

    2006-01-01

    The clinical benefit of currently available tar blend shampoos for the treatment of scalp psoriasis is restricted due to their limited efficacy, low cosmetic appeal and potential for carcinogenicity. This 4-week multicentre, randomized, parallel-group, investigator-masked study included 162 subjects and aimed to compare the efficacy, safety and cosmetic acceptability of clobetasol propionate 0.05% shampoo versus a currently marketed tar blend 1% shampoo in subjects with moderate to severe scalp psoriasis. Clobetasol propionate shampoo was superior to tar blend shampoo with respect to all efficacy variables tested (p<0.001): Total and Global Severity Score; erythema; plaque thickening; desquamation; pruritus; total scalp area involved; and the subject's global assessment of clinical improvement. Both treatments were safe and well-tolerated. Furthermore, more subjects indicated that clobetasol propionate shampoo was more cosmetically acceptable than tar blend shampoo. Clobetasol propionate 0.05% shampoo is a good alternative to tar blend shampoo in the treatment of moderate to severe scalp psoriasis.

  8. Impact of Genetic Variations in HIV-1 Tat on LTR-Mediated Transcription via TAR RNA Interaction.

    PubMed

    Ronsard, Larance; Ganguli, Nilanjana; Singh, Vivek K; Mohankumar, Kumaravel; Rai, Tripti; Sridharan, Subhashree; Pajaniradje, Sankar; Kumar, Binod; Rai, Devesh; Chaudhuri, Suhnrita; Coumar, Mohane S; Ramachandran, Vishnampettai G; Banerjea, Akhil C

    2017-01-01

    HIV-1 evades host defense through mutations and recombination events, generating numerous variants in an infected patient. These variants with an undiminished virulence can multiply rapidly in order to progress to AIDS. One of the targets to intervene in HIV-1 replication is the trans -activator of transcription (Tat), a major regulatory protein that transactivates the long terminal repeat promoter through its interaction with trans -activation response (TAR) RNA. In this study, HIV-1 infected patients ( n = 120) from North India revealed Ser46Phe (20%) and Ser61Arg (2%) mutations in the Tat variants with a strong interaction toward TAR leading to enhanced transactivation activities. Molecular dynamics simulation data verified that the variants with this mutation had a higher binding affinity for TAR than both the wild-type Tat and other variants that lacked Ser46Phe and Ser61Arg. Other mutations in Tat conferred varying affinities for TAR interaction leading to differential transactivation abilities. This is the first report from North India with a clinical validation of CD4 counts to demonstrate the influence of Tat genetic variations affecting the stability of Tat and its interaction with TAR. This study highlights the co-evolution pattern of Tat and predominant nucleotides for Tat activity, facilitating the identification of genetic determinants for the attenuation of viral gene expression.

  9. Marketing 'less harmful, low-tar' cigarettes is a key strategy of the industry to counter tobacco control in China.

    PubMed

    Yang, Gonghuan

    2014-03-01

    While the 'low-tar' scheme has been widely recognised as a misleading tactic used by the tobacco industry to deceive the public about the true risks of cigarette smoking, a similar campaign using the slogan of 'less harmful, low tar' was launched by the Chinese tobacco industry, that is, State Tobacco Monopoly Administration/China National Tobacco Corporation and began to gain traction during the last decade. Despite the fact that no sufficient research evidence supports the claims made by the industry that these cigarettes are safer, the Chinese tobacco industry has continued to promote them using various health claims. As a result, the production and sales of 'less harmful, low-tar' cigarettes have increased dramatically since 2000. Recently, a tobacco industry senior researcher, whose main research area is 'less harmful, low-tar' cigarettes, was elected as an Academician to the prestigious Chinese Academy of Engineering for his contribution to developing 'less harmful, low-tar' cigarettes. The tobacco researcher's election caused an outcry from the tobacco control community and the general public in China. This paper discusses the Chinese tobacco industry's 'less harmful, low-tar' initiatives and calls for the Chinese government to stop the execution of this deceptive strategy for tobacco marketing.

  10. Streamflow, Water Quality, and Metal Loads from Chat Leachate and Mine Outflow into Tar Creek, Ottawa County, Oklahoma, 2005

    USGS Publications Warehouse

    Cope, Caleb C.; Becker, Mark F.; Andrews, William J.; DeHay, Kelli

    2008-01-01

    Picher mining district is an abandoned lead and zinc mining area located in Ottawa County, northeastern Oklahoma. During the first half of the 20th century, the area was a primary producer of lead and zinc in the United States. Large accumulations of mine tailings, locally referred to as chat, produce leachate containing cadmium, iron, lead, and zinc that enter drainages within the mining area. Metals also seep to local ground water and streams from unplugged shafts, vent holes, seeps, and abandoned mine dewatering wells. Streamflow measurements were made and water-quality samples were collected and analyzed from two locations in Picher mining district from August 16 to August 29 following a rain event beginning on August 14, 2005, to determine likely concentrations and loads of metals from tailings and mine outflows in the part of Picher mining district near Tar Creek. Locations selected for sampling included a tailings pile with an adjacent mill pond, referred to as the Western location, and a segment of Tar Creek from above the confluence with Lytle Creek to below Douthat bridge, referred to as Tar Creek Study Segment. Measured streamflow was less than 0.01 cubic foot per second at the Western location, with streamflow only being measurable at that site on August 16, 2005. Measured streamflows ranged from <0.01 to 2.62 cubic feet per second at Tar Creek Study Segment. One water-quality sample was collected from runoff at the Western location. Total metals concentrations in that sample were 95.3 micrograms per liter cadmium, 182 micrograms per liter iron, 170 micrograms per liter lead, 1,760 micrograms per liter zinc. Total mean metals concentrations in 29 water-quality samples collected from Tar Creek Study Segment from August 16-29, 2005, were 21.8 micrograms per liter cadmium, 7,924 micrograms per liter iron, 7.68 micrograms per liter lead, and 14,548 micrograms per liter zinc. No metals loading values were calculated for the Western location. Metals loading

  11. Identification and characterization of a HeLa nuclear protein that specifically binds to the trans-activation-response (TAR) element of human immunodeficiency virus.

    PubMed Central

    Marciniak, R A; Garcia-Blanco, M A; Sharp, P A

    1990-01-01

    Human immunodeficiency virus type 1 RNAs contain a sequence, trans-activation-response (TAR) element, which is required for tat protein-mediated trans-activation of viral gene expression. We have identified a nuclear protein from extracts of HeLa cells that binds to the TAR element RNA in a sequence-specific manner. The binding of this 68-kDa polypeptide was detected by UV cross-linking proteins to TAR element RNA transcribed in vitro. Competition experiments were performed by using a partially purified preparation of the protein to quantify the relative binding affinities of TAR element RNA mutants. The binding affinity of the TAR mutants paralleled the reported ability of those mutants to support tat trans-activation in vivo. We propose that this cellular protein moderates TAR activity in vivo. Images PMID:2333305

  12. Pyrolysis characteristics and kinetics of acid tar waste from crude benzol refining: A thermogravimetry-mass spectrometry analysis.

    PubMed

    Chihobo, Chido H; Chowdhury, Arindrajit; Kuipa, Pardon K; Simbi, David J

    2016-12-01

    Pyrolysis is an attractive thermochemical conversion technology that may be utilised as a safe disposal option for acid tar waste. The kinetics of acid tar pyrolysis were investigated using thermogravimetry coupled with mass spectrometry under a nitrogen atmosphere at different heating rates of 10, 15 and 20 K min -1 The thermogravimetric analysis shows three major reaction peaks centred around 178 °C, 258 °C, and 336 °C corresponding to the successive degradation of water soluble lower molecular mass sulphonic acids, sulphonated high molecular mass hydrocarbons, and high molecular mass hydrocarbons. The kinetic parameters were evaluated using the iso-conversional Kissinger-Akahira-Sunose method. A variation in the activation energy with conversion revealed that the pyrolysis of the acid tar waste progresses through complex multi-step kinetics. Mass spectrometry results revealed a predominance of gases such as hydrogen, methane and carbon monoxide, implying that the pyrolysis of acid tar waste is potentially an energy source. Thus the pyrolysis of acid tar waste may present a viable option for its environmental treatment. There are however, some limitations imposed by the co-evolution of corrosive gaseous components for which appropriate considerations must be provided in both pyrolysis reactor design and selection of construction materials. © The Author(s) 2016.

  13. Social-cognitive remediation in schizophrenia: generalization of effects of the Training of Affect Recognition (TAR).

    PubMed

    Wölwer, Wolfgang; Frommann, Nicole

    2011-09-01

    In the last decade, several social cognitive remediation programs have been developed for use in schizophrenia. Though existing evidence indicates that such programs can improve social cognition, which is essential for successful social functioning, it remains unclear whether the improvements generalize to social cognitive domains not primarily addressed by the intervention and whether the improved test performance transfers into everyday social functioning. The present study investigated whether, beyond its known effects on facial affect recognition, the Training of Affect Recognition (TAR) has effects on prosodic affect recognition, theory of mind (ToM) performance, social competence in a role-play task, and more general social and occupational functioning. Thirty-eight inpatients with a diagnosis of schizophrenia or schizoaffective disorder were randomly assigned to 6 weeks of treatment with the TAR--primarily targeted at facial affect recognition-or Cognitive Remediation Training (CRT)--primarily targeted at neurocognition. Intention-to-treat analyses found significantly larger pre-post improvements with TAR than with CRT in prosodic affect recognition, ToM, and social competence and a trend effect in global social functioning. However, the effects on ToM and social competence were no longer significant in the smaller group of patients who completed treatment according to protocol. Results suggest that TAR effects generalize to other social cognitive domains not primarily addressed. TAR may also enhance social skills and social functioning, although this has to be confirmed. Results are discussed with regard to the need to improve functional outcome in schizophrenia against the background of current evidence from other social cognitive remediation approaches.

  14. Final report on the safety assessment of Juniperus communis Extract, Juniperus oxycedrus Extract, Juniperus oxycedrus Tar, Juniperus phoenicea extract, and Juniperus virginiana Extract.

    PubMed

    2001-01-01

    derived from J. communis and J. virginiana and Juniperus Oxycedrus Tar were not skin irritants in animals. The oil from J. virginiana was not a sensitizer, and the oil from J. communis was not phototoxic in animal tests. Juniperus Oxycedrus Tar was genotoxic in several assays. No genotoxicity data were available for any of the extracts. Juniperus Communis Extract did affect fertility and was abortifacient in studies using albino rats. Clinical tests showed no evidence of irritation or sensitization with any of the tested oils, but some evidence of sensitization to the tar. These data were not considered sufficient to assess the safety of these ingredients. Additional data needs include current concentration of use data; function in cosmetics; methods of manufacturing and impurities data, especially pesticides; ultraviolet (UV) absorption data; if absorption occurs in the UVA or UVB range, photosensitization data are needed; dermal reproductive/developmental toxicity data (to include determination of a no-effect level); two genotoxicity assays (one in a mammalian system) for each extract; if positive, a 2-year dermal carcinogenicity assay performed using National Toxicology Program (NTP) methods is needed; a 2-year dermal carcinogenicity assay performed using NTP methods on Juniperus Oxycedrus Tar; and irritation and sensitization data on each extract and the tar (these data are needed because the available data on the oils cannot be extrapolated). Until these data are available, it is concluded that the available data are insufficient to support the safety of these ingredients in cosmetic formulations.

  15. Cigarettes, lung cancer, and coronary heart disease: the effects of inhalation and tar yield.

    PubMed

    Higenbottam, T; Shipley, M J; Rose, G

    1982-06-01

    Ten-year mortality rates for lung cancer and coronary heart disease have been related to cigarette smoking habits in 17 475 male civil servants aged 40-64 and in sample of 8089 male British residents aged 35-69. Both diseases were more frequent in smokers. Lung cancer rates were higher overall for "non-inhalers", particularly in heavy smokers. Tar yield correlated with the risk of lung cancer in non-inhalers but less so in inhalers. Conversely, coronary deaths were more common among inhalers, and the effect of tar/nicotine yield (such as it was) was confined to inhalers. It appears that there are subtle interactions between the amount smoked, the tar/nicotine yield of the cigarette, and the style of smoking. Thus the effects of a change in cigarette characteristics are hard to predict, and they may be different for respiratory and cardiovascular disease.

  16. Properties of gasification-derived char and its utilization for catalytic tar reforming

    NASA Astrophysics Data System (ADS)

    Qian, Kezhen

    Char is a low-value byproduct of biomass gasification and pyrolysis with many potential applications, such as soil amendment and the synthesis of activated carbon. The overall goal of the proposed research was to develop novel methods to use char derived from gasification for high-value applications in syngas conditioning. The first objective was to investigate effects of gasification condition and feedstock on properties of char derived from fluidized bed gasification. Results show that the surface areas of most of the char were 1--10 m 2/g and increased as the equivalence ratio increased. Char moisture and fixed carbon contents decreased while ash content increased as equivalence ratio increased. The next objective was to study the properties of sorghum and red cedar char derived from downdraft gasifier. Red cedar char contained more aliphatic carbon and o-alkyl carbon than sorghum char. Char derived from downdraft gasification had higher heating values and lower ash contents than char derived from fluidized bed gasification. The gasification reactivity of red cedar char was higher than that of sorghum char. Then, red cedar char based catalysts were developed with different preparation method to reform toluene and naphthalene as model tars. The catalyst prepared with nickel nitrate was found to be better than that with nickel acetate. The nickel particle size of catalyst impregnated with nickel nitrate was smaller than that of catalyst impregnated with nickel acetate. The particle size of catalyst impregnated with nickel acetate decreased by hydrazine reduction. The catalyst impregnated with nickel nitrate had the highest toluene removal efficiency, which was 70%--100% at 600--800 °C. The presence of naphthalene in tar reduced the catalyst efficiency. The toluene conversion was 36--99% and the naphthalene conversion was 37%--93% at 700--900 °C. Finally, effects of atmosphere and pressure on catalytic reforming of lignin-derived tars over the developed catalyst

  17. Characterization of alkanes, hopanes, and polycyclic aromatic hydrocarbons (PAHs) in tar-balls collected from the East Coast of Peninsular Malaysia.

    PubMed

    Chandru, Kuhan; Zakaria, Mohamad Pauzi; Anita, Sofia; Shahbazi, Azadeh; Sakari, Mahyar; Bahry, Pourya Shahpoury; Mohamed, Che Abd Rahim

    2008-05-01

    The East Coast of Peninsular Malaysia faces the South China Sea and is vulnerable to oil pollution because of intense petroleum production activities in the area. The South China Sea is also a favored route for supertankers carrying crude oil to the Far East. Consequently, oil spills can occur, causing pollution and contamination in the surrounding areas. Residual oil spills stranded on coastal beaches usually end up as tar-balls. Elucidating the sources of tar-balls using a molecular marker approach is essential in assessing environmental impacts and perhaps settling legal liabilities for affected parties. This study utilizes a multimodal molecular marker approach through the use of diagnostic ratios of alkanes, hopanes, and polycyclic aromatic hydrocarbons (PAHs) to determine the source, distribution and weathering of tar-balls. Hopane ratios (e.g., C29/C30, and summation C31-C35/C30 ratios) were used to identify the sources of tar-balls. The weathering effects were distinguished by using alkanes, namely the unresolved complex mixture (UCM) and low molecular weight/high molecular weight (L/H) ratios. Similarly, PAHs were also used for the determination of weathering processes undergone by the tar-balls. This multimodal molecular marker gave a very strong indication of the sources of tar-balls in this study. For example, 16 out of 17 samples originated from South East Asian Crude Oil (SEACO) with one sample from Merang, Terengganu originating from North Sea Oil (Troll). The TRME-2 sample may have come from a supertanker's ballast water discharge. The second possibility is that the tar-ball may have been transported via oceanographic currents. All 'weathered' sample characterizations were based on the presence of UCM and other ratios. The multimodal molecular marker approach applied in this study has enabled us to partially understand the transport behavior of tar-balls in the marine environment and has revealed insights into the weathering process of tar-balls.

  18. Microbes in Beach Sands: Integrating Environment, Ecology and Public Health

    PubMed Central

    Whitman, Richard; Harwood, Valerie J.; Edge, Thomas A.; Nevers, Meredith; Byappanahalli, Muruleedhara; Vijayavel, Kannappan; Brandão, João; Sadowsky, Michael J.; Alm, Elizabeth Wheeler; Crowe, Allan; Ferguson, Donna; Ge, Zhongfu; Halliday, Elizabeth; Kinzelman, Julie; Kleinheinz, Greg; Przybyla-Kelly, Kasia; Staley, Christopher; Staley, Zachery; Solo-Gabriele, Helena M.

    2014-01-01

    SUMMARY Beach sand is a habitat that supports many microbes, including viruses, bacteria, fungi and protozoa (micropsammon). The apparently inhospitable conditions of beach sand environments belie the thriving communities found there. Physical factors, such as water availability and protection from insolation; biological factors, such as competition, predation, and biofilm formation; and nutrient availability all contribute to the characteristics of the micropsammon. Sand microbial communities include autochthonous species/phylotypes indigenous to the environment. Allochthonous microbes, including fecal indicator bacteria (FIB) and waterborne pathogens, are deposited via waves, runoff, air, or animals. The fate of these microbes ranges from death, to transient persistence and/or replication, to establishment of thriving populations (naturalization) and integration in the autochthonous community. Transport of the micropsammon within the habitat occurs both horizontally across the beach, and vertically from the sand surface and ground water table, as well as at various scales including interstitial flow within sand pores, sediment transport for particle-associated microbes, and the large-scale processes of wave action and terrestrial runoff. The concept of beach sand as a microbial habitat and reservoir of FIB and pathogens has begun to influence our thinking about human health effects associated with sand exposure and recreational water use. A variety of pathogens have been reported from beach sands, and recent epidemiology studies have found some evidence of health risks associated with sand exposure. Persistent or replicating populations of FIB and enteric pathogens have consequences for watershed/beach management strategies and regulatory standards for safe beaches. This review summarizes our understanding of the community structure, ecology, fate, transport, and public health implications of microbes in beach sand. It concludes with recommendations for future

  19. Exploring the chemical composition of pelagic tar collected in the North Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Green, H. S.; Reddy, C. M.; Valentine, D. L.; Aeppli, C.; Swarthout, B.; Sharpless, C.; Joyce, P.; Meyer, A. W.; Fuller, S. A.; Gosselin, K.

    2016-12-01

    Pelagic tarballs have been linked to multiple sources and their abundances follow notable historical and geographic trends. An overwhelming number of studies point to operational discharges (cargo washing) as the main source of pelagic tar. In a recent review article, Warnock et al. (2015) summarized that the abundance of tar balls has decreased over the last 30 years. The decreasing trend of tarballs has been attributed to the MARPOL 73/78 Annex I legislation, which was created from conventions held in 1973 and again in 1978 to respond to several tanker accidents and other pollution-related inputs. Two of the studies supporting the "MARPOL 73/78 effect" were based on the historical record of tarballs collected in the North Atlantic Ocean by the Sea Education Association (SEA; Woods Hole, MA). To supplement the SEA record, we performed a series of geochemical analyses on 100 of the SEA samples collected from 1988 to 2014. Bulk and gas chromatographic (GC) analyses revealed that the samples were highly variable. For example, the amount of material that could be dissolved in organic solvent but not measured by gas chromatography (referred to as the % GC amenable, a proxy on the distribution of compound classes that compose the tar) ranged from 10 to 80%, although skewed to values less than 40%. Another parameter, based on the GC data, was the perecentage of the resolved relative to the unresolved signal spanned from 0.1 to 1.8. Nine of the sampes would not dissolve in organic solvents and appear to be soot or coal. This study has an operation limitation as we choose to only examine samples > 1 cm (relative to samples smaller than 1mm). Our approach was based on the assumption that these samples were the most unlikely to be weathered and hence retain the genetic features of the initially released tar. While this study does not have the capacity to test confidently the MARPOL 73/78 effect, it does show that pelagic tars are highly variable, which in turn, have

  20. Membrane curvature and the Tol-Pal complex determine polar localization of the chemoreceptor Tar in E. coli.

    PubMed

    Saaki, Terrens N V; Strahl, Henrik; Hamoen, Leendert W

    2018-02-20

    Chemoreceptors are localized at the cell poles of Escherichia coli and other rod-shaped bacteria. Over the years different mechanisms have been put forward to explain this polar localization; from stochastic clustering, membrane curvature driven localization, interactions with the Tol-Pal complex, to nucleoid exclusion. To evaluate these mechanisms, we monitored the cellular localization of the aspartate chemoreceptor Tar in different deletion mutants. We did not find any indication for either stochastic cluster formation or nucleoid exclusion. However, the presence of a functional Tol-Pal complex appeared to be essential to retain Tar at cell poles. Interestingly, Tar still accumulated at midcell in tol and in pal deletion mutants. In these mutants, the protein appears to gather at the base of division septa, a region characterised by strong membrane curvature. Chemoreceptors, like Tar, form trimer-of-dimers that bend the cell membrane due to a rigid tripod structure. The curvature approaches the curvature of the cell membrane generated during cell division, and localization of chemoreceptor tripods at curved membrane areas is therefore energetically favourable as it lowers membrane tension. Indeed, when we introduced mutations in Tar that abolish the rigid tripod structure, the protein was no longer able to accumulate at midcell or cell poles. These findings favour a model where chemoreceptor localization in E. coli is driven by strong membrane curvature and association with the Tol-Pal complex. Importance Bacteria have exquisite mechanisms to sense and to adapt to the environment they live in. One such mechanism involves the chemotaxis signal transduction pathway, in which chemoreceptors specifically bind certain attracting or repelling molecules and transduce the signals to the cell. In different rod-shaped bacteria, these chemoreceptors localize specifically to cell poles. Here, we examined the polar localization of the aspartate chemoreceptor Tar in E. coli

  1. Tar-free fuel gas production from high temperature pyrolysis of sewage sludge

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Leguan; Xiao, Bo; Hu, Zhiquan

    2014-01-15

    Highlights: • High temperature pyrolysis of sewage sludge was efficient for producing tar-free fuel gas. • Complete tar removal and volatile matter release were at elevated temperature of 1300 °C. • Sewage sludge was converted to residual solid with high ash content. • 72.60% of energy conversion efficiency for gas production in high temperature pyrolysis. • Investment and costing for tar cleaning were reduced. - Abstract: Pyrolysis of sewage sludge was studied in a free-fall reactor at 1000–1400 °C. The results showed that the volatile matter in the sludge could be completely released to gaseous product at 1300 °C. Themore » high temperature was in favor of H{sub 2} and CO in the produced gas. However, the low heating value (LHV) of the gas decreased from 15.68 MJ/N m{sup 3} to 9.10 MJ/N m{sup 3} with temperature increasing from 1000 °C to 1400 °C. The obtained residual solid was characterized by high ash content. The energy balance indicated that the most heating value in the sludge was in the gaseous product.« less

  2. Brown carbon in tar balls from smoldering biomass combustion

    Treesearch

    R. K. Chakrabarty; H. Moosmuller; L.-W. A. Chen; K. Lewis; W. P. Arnott; C. Mazzoleni; M. K. Dubey; C. E. Wold; W. M. Hao; S. M. Kreidenweis

    2010-01-01

    We report the direct observation of laboratory production of spherical, carbonaceous particles - "tar balls" - from smoldering combustion of two commonly occurring dry mid-latitude fuels. Real-time measurements of spectrally varying absorption Angstrom coefficients (AAC) indicate that a class of light absorbing organic carbon (OC) with wavelength dependent...

  3. Radiocarbon dating of extinct fauna in the Americas recovered from tar pits

    NASA Astrophysics Data System (ADS)

    Jull, A. J. T.; Iturralde-Vinent, M.; O'Malley, J. M.; MacPhee, R. D. E.; McDonald, H. G.; Martin, P. S.; Moody, J.; Rincón, A.

    2004-08-01

    We have obtained radiocarbon dates by accelerator mass spectrometry on bones of extinct large mammals from tar pits. Results on some samples of Glyptodon and Holmesina (extinct large mammals similar to armadillos) yielded ages of >25 and >21 ka, respectively. We also studied the radiocarbon ages of three different samples of bones from the extinct Cuban ground sloth, Parocnus bownii, which yielded dates ranging from 4960 ± 280 to 11 880 ± 420 yr BP. In order to remove the tar component pretreat the samples sufficiently to obtain reliable dates, we cleaned the samples by Soxhlet extraction in benzene. Resulting samples of collagenous material were often small.

  4. Industrial sand and gravel

    USGS Publications Warehouse

    Dolley, T.P.

    2011-01-01

    Domestic production of industrial sand and gravel in 2010 was about 26.5 Mt (29.2 million st), a 6-percent increased from 2009. Certain end uses of industrial sand and gravel, such as sand for container glass, golf course sand, recreational sand, specialty glass and water filtration, showed increased demand in 2010.

  5. Sand Sources Near Athabasca Valles

    NASA Image and Video Library

    2014-10-29

    This image captured by NASA Mars Reconnaissance Orbiter shows a small channel cutting into young volcanic lavas in a region where massive catastrophic flooding took place in the relatively recent past. The Athabasca Valles region includes a vast lava flow, thought to be the youngest on Mars, with even younger outflow channels that were carved by running water. The source of the water is believed to be the Cerberus Fossae valleys to the north, which may have penetrated to an over-pressurized aquifer in the subsurface. Nowadays, erosion by gravity, wind, and frost gradually wears down the rims of the outflow channels. In this scene, we see dark materials along the channel rim that were probably exposed by this erosion. The dark materials are less red than the surrounding surface and so they appear blue in this enhanced color picture. Viewed close up, the dark materials show ripples that suggest they are made up of mobile sand. It is possible that this sand originated elsewhere and simply collected where we see it today, but the fact that sand is not found elsewhere in the scene suggest to us that it is eroding out of the volcanic layers at the retreating rim of the channel. Sand sources are important because mobile sand grains have only a limited lifetime, wearing down and chipping apart each time they impact the surface. Erosion of the volcanic materials in this region may provide sands to replace those that are destroyed. Few such sand sources have so far been identified on Mars. http://photojournal.jpl.nasa.gov/catalog/PIA18889

  6. Tar Creek study, Sargent oil field, Santa Clara County, California

    USGS Publications Warehouse

    Wagner, David L.; Fedasko, Bill; Carnahan, J.R.; Brunetti, Ross; Magoon, Leslie B.; Lillis, Paul G.; Lorenson, T.D.; Stanley, Richard G.

    2002-01-01

    Field work in the Tar Creek area of Sargent oil field was performed June 26 to 28, 2000. The Santa Clara County study area is located in Sections, 30, 31, and 32, Township 11 South, Range 4 East, M.D.B&M; and in Sections 25 and 36, Township 11 South, Range 3 East, M.D.B.&M., north and south of Tar Creek, west of Highway 101. The work was a cooperative effort of the California Department of Conservation's Division of Oil, Gas, and Geothermal Resources (DOGGR), California Geological Survey (CGS), and the United States Geological Survey (USGS). The purpose of the project was to map the stratigraphy and geologic structure (David Wagner, CGS); sample oil for age dating (Les Magoon, USGS); and search for undocumented wells plus conduct a GPS survey of the area (Bill Fedasko, J.P. Carnahan, and Ross Brunetti, DOGGR)

  7. Coal-tar pavement sealants might substantially increase children's PAH exposures

    USGS Publications Warehouse

    Williams, E. Spencer; Mahler, Barbara J.; Van Metre, Peter C.

    2012-01-01

    Dietary ingestion has been identified repeatedly as the primary route of human exposure to polycyclic aromatic hydrocarbons (PAHs), seven of which are classified as probable human carcinogens (B2 PAHs) by the U.S. EPA. Humans are exposed to PAHs through ingestion of cooked and uncooked foods, incidental ingestion of soil and dust, inhalation of ambient air, and absorption through skin. Although PAH sources are ubiquitous in the environment, one recently identified PAH source stands out: Coal-tar-based pavement sealant—a product applied to many parking lots, driveways, and even playgrounds primarily in the central, southern, and eastern U.S.—has PAH concentrations 100–1000 times greater than most other PAH sources. It was reported recently that PAH concentrations in house dust in residences adjacent to parking lots with coal-tar-based sealant were 25 times higher than in residences adjacent to unsealed asphalt parking lots.

  8. Citizen science identifies the effects of nitrogen dioxide and other environmental drivers on tar spot of sycamore.

    PubMed

    Gosling, Laura; Ashmore, Mike; Sparks, Tim; Bell, Nigel

    2016-07-01

    Elevated sulphur dioxide (SO2) concentrations were the major cause of the absence of symptoms of tar spot (Rhytisma acerinum) of sycamore (Acer pseudoplatanus), in urban areas in the 1970s. The subsequent large decline in SO2 concentrations has not always been accompanied by increased tar spot symptoms, for reasons that have remained unresolved. We used a large citizen science survey, providing over 1000 records across England, to test two competing hypotheses proposed in earlier studies. We were able to demonstrate the validity of both hypotheses; tar spot symptoms were reduced where there were fewer fallen leaves as a source of inoculum, and elevated nitrogen dioxide concentrations reduced tar spot symptoms above a threshold concentration of about 20 μg m(-3). Symptom severity was also lower at sites with higher temperature and lower rainfall. Our findings demonstrate the power of citizen science to resolve competing hypotheses about the impacts of air pollution and other environmental drivers. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Effect of cavitation on the properties of coal-tar pitch as studied by gas-liquid chromatography

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    M.I. Baikenov; T.B. Omarbekov; S.K. Amerkhanova

    2008-02-15

    The applicability of the cavitation-wave effect to coal-tar pitch processing is considered. The results of the GLC analysis of the test material before and after rotor-pulsation cavitation treatment are given. The organic matter of coal-tar pitch was found to degrade upon cavitation; as a result of this, the yields of light and medium fractions considerably increased. 5 refs., 2 figs., 4 tabs.

  10. Near-infrared spectroscopy of primitive solar system objects

    NASA Technical Reports Server (NTRS)

    Luu, Jane; Jewitt, David; Cloutis, Edward

    1994-01-01

    We have obtained near-infrared (H and K band at lambda/Delta(lambda) is approximately 480 to 600) spectra of a sample of primitive objects including 2 Centaur objects (2060 Chiron and 5145 Pholus) and 16 P- and D-type asteroids. The spectra were obtained at the United Kingdom Infrared Telescope using the cooled grating spectrometer CGS4, and were used to search for chemically diagnostic vibrational features in these primitive objects. Pholus exhibits broad adsorption features at 2.07 and 2.27 micrometers, as well as a weak feature at 1.72 micrometers. The 1.72- and 2.27-micrometer features are similar to those seen in a laboratory tar sand sample. No distinct absorption features are found in other objects, including Chiron, which displays a spectrally neutral continuum. A comparison of the P- and D-type asteroid spectra with laboratory measurements of organic solids shows no compelling evidence for hydrocarbon overtones seen in terrestrial bituminous tar sands.

  11. Erosion and Deposition in Schaeberle Crater

    NASA Image and Video Library

    2016-01-14

    Schaeberle Crater is a large, heavily-infilled crater with many interesting features. This image NASA Mars Reconnaissance Orbiter spacecraft shows a window into the crater fill deposit, showcasing eroding bedrock and aeolian landforms. This pit is located near the geometric center of our image, making it a central pit crater. Central pit craters are thought to form from impact melt draining through subsurface cracks in the deepest part of the crater shortly following impact. A closeup image shows light-toned bedrock and a small cliff that appears to be weathering away. Below the cliff there are several different types of aeolian features, including ripples and transverse aeolian ridges (TAR). The sand that forms the small, bluish ripples may be weathering out of the cliff face, in contrast to the larger, light-toned TAR which are thought to be currently inactive. More of the TAR are visible in another closeup image. In this case, they are clearly covered by a dark, ripple-covered sand sheet. We have only imaged this location once, so it is impossible to determine whether or not the sand sheet is blowing in the wind. But due to repeated HiRISE imaging in other areas, active dunes are now known to be common across Mars and we can reasonably speculate that these dunes are moving, too. http://photojournal.jpl.nasa.gov/catalog/PIA20339

  12. Fecal indicators in sand, sand contact, and risk of enteric illness among beachgoers

    PubMed Central

    Heaney, Christopher D.; Sams, Elizabeth; Dufour, Alfred P.; Brenner, Kristen P.; Haugland, Richard A.; Chern, Eunice; Wing, Steve; Marshall, Stephen; Love, David C.; Serre, Marc; Noble, Rachel; Wade, Timothy J.

    2011-01-01

    Background Beach sand can harbor fecal indicator organisms and pathogens, but enteric illness risk associated with sand contact remains unclear. Methods In 2007, visitors at two recreational marine beaches were asked on the day of their visit about sand contact. Ten to 12 days later, participants answered questions about health symptoms since the visit. F+ coliphage, Enterococcus, Bacteroidales, fecal Bacteroides, and Clostridium spp. in wet sand were measured using culture and molecular methods. Results We analyzed 144 wet sand samples and completed 4,999 interviews. Adjusted odds ratios (aORs) were computed, comparing those in the highest tertile of fecal indicator exposure with those who reported no sand contact. Among those digging in sand compared with those not digging in sand, a molecular measure of Enterococcus spp. (calibrator cell equivalents/g) in sand was positively associated with gastrointestinal (GI) illness (aOR = 2.0 [95% confidence interval (CI) = 1.2–3.2]) and diarrhea (2.4 [1.4–4.2]). Among those buried in sand, point estimates were greater for GI illness (3.3 [1.3–7.9]) and diarrhea (4.9 [1.8–13]). Positive associations were also observed for culture-based Enterococcus (colony-forming units/g) with GI illness (aOR digging = 1.7 [1.1–2.7]) and diarrhea (2.1 [1.3–3.4]). Associations were not found among non-swimmers with sand exposure. Conclusions We observed a positive relationship between sand contact activities and enteric illness as a function of concentrations of fecal microbial pollution in beach sand. PMID:22157306

  13. Documenting the global impacts of beach sand mining

    NASA Astrophysics Data System (ADS)

    Young, R.; Griffith, A.

    2009-04-01

    For centuries, beach sand has been mined for use as aggregate in concrete, for heavy minerals, and for construction fill. The global extent and impact of this phenomenon has gone relatively unnoticed by academics, NGOs, and major news sources. Most reports of sand mining activities are found at the very local scale (if the mining is ever documented at all). Yet, sand mining in many localities has resulted in the complete destruction of beach (and related) ecosystems along with severe impacts to coastal protection and tourism. The Program for the Study of Developed Shorelines at Western Carolina University and Beachcare.org have initiated the construction of a global database of beach sand mining activities. The database is being built through a combination of site visits and through the data mining of media resources, peer reviewed papers, and reports from private and governmental entities. Currently, we have documented sand mining in 35 countries on 6 continents representing the removal of millions of cubic meters of sand. Problems extend from Asia where critical infrastructure has been disrupted by sand mining to the Caribbean where policy reform has swiftly followed a highly publicized theft of sand. The Program for the Study of Developed Shorelines recently observed extensive sand mining in Morocco at the regional scale. Tens of kilometers of beach have been stripped of sand and the mining continues southward reducing hope of a thriving tourism-based economy. Problems caused by beach sand mining include: destruction of natural beaches and the ecosystems they protect (e.g. dunes, wetlands), habitat loss for globally important species (e.g. turtles, shorebirds), destruction of nearshore marine ecosystems, increased shoreline erosion rates, reduced protection from storms, tsunamis, and wave events, and economic losses through tourist abandonment and loss of coastal aesthetics. The threats posed by sand mining are made even more critical given the prospect of a

  14. PAHs underfoot: Contaminated dust from coal-tar sealcoated pavement is widespread in the United States

    USGS Publications Warehouse

    Van Metre, P.C.; Mahler, B.J.; Wilson, J.T.

    2009-01-01

    We reported in 2005 that runoff from parking lots treated with coal-tar-based sealcoat was a major source of polycyclic aromatic hydrocarbons (PAHs) to streams in Austin, Texas. Here we present new data from nine U. S. cities that show nationwide patterns in concentrations of PAHs associated with sealcoat Dust was swept from parking lots in six cities in the central and eastern U. S., where coal-tar-based sealcoat dominates use, and three cities in the western U. S., where asphalt-based sealcoat dominates use. For six central and eastern cities, median ?? PAH concentrations in dust from sealcoated and unsealcoated pavement are 2200 and 27 mg/kg, respectively. For three western cities, median ?? PAH concentrations in dust from sealcoated and unsealcoated pavement are similar and very low (2. 1 and 0. 8 mg/kg, respectively). Lakes in the central and eastern cities where pavement was sampled have bottom sediments with higher PAH concentrations than do those in the western cities relative to degree of urbanization. Bottom-sediment PAH assemblages are similar to those of sealcoated pavement dust regionally, implicating coal-tar-based sealcoat as a PAH source to the central and eastern lakes. Concentrations of benzo[a]pyrene in dust from coal-tar sealcoated pavement and adjacent soils greatly exceed generic soil screening levels, suggesting that research on human-health risk is warranted.

  15. Uptake of pyrene in a breast-fed child of a mother treated with coal tar.

    PubMed

    Scheepers, Paul T J; van Houtum, Jeanette L M; Anzion, Rob B M; Harder, Rianne; Bos, Rob P; van der Valk, Pieter G M

    2009-01-01

    A woman was treated for atopic dermatitis with coal tar containing ointments. Coal tar containing ointments contain genotoxic polycyclic aromatic hydrocarbons. Over a period of 50 days the accumulated dose of different coal tar containing ointments treatments corresponded to 993 mg of pyrene and 464 mg of benz[a]pyrene. During this treatment she gave breast milk to her 3-month-old daughter. Analysis of urine samples from the breast-fed child showed elevated levels of urinary excretion of a metabolite of pyrene (1-hydroxypyrene, 1-OHP). These levels were in the same range as urinary excretion levels of this metabolite observed in the mother's urine. As no pyrene was observed in breast milk at a limit of determination of 0.0035 micromol/L, transfer of pyrene from mother to child via breast milk is not likely. Also, a low level of 1-hydroxypyrene observed in the mother's milk did not account for the observed urinary excretion levels in the child. It must therefore be assumed that pyrene was transferred from mother to child via another route, presumably direct skin-to-skin or skin-to-mouth contact. Dermatologists should inform their patients who receive treatment with coal tar containing ointments of the risk of transfer of polycyclic aromatic hydrocarbons by skin-to-skin or skin-to-mouth contact.

  16. PeaTAR1B: Characterization of a Second Type 1 Tyramine Receptor of the American Cockroach, Periplaneta americana

    PubMed Central

    Balfanz, Sabine

    2017-01-01

    The catecholamines norepinephrine and epinephrine regulate important physiological functions in vertebrates. In insects; these neuroactive substances are functionally replaced by the phenolamines octopamine and tyramine. Phenolamines activate specific guanine nucleotide-binding (G) protein-coupled receptors (GPCRs). Type 1 tyramine receptors are better activated by tyramine than by octopamine. In contrast; type 2 tyramine receptors are almost exclusively activated by tyramine. Functionally; activation of type 1 tyramine receptors leads to a decrease in the intracellular concentration of cAMP ([cAMP]i) whereas type 2 tyramine receptors can mediate Ca2+ signals or both Ca2+ signals and effects on [cAMP]i. Here; we report that the American cockroach (Periplaneta americana) expresses a second type 1 tyramine receptor (PeaTAR1B) in addition to PeaTAR1A (previously called PeaTYR1). When heterologously expressed in flpTM cells; activation of PeaTAR1B by tyramine leads to a concentration-dependent decrease in [cAMP]i. Its activity can be blocked by a series of established antagonists. The functional characterization of two type 1 tyramine receptors from P. americana; PeaTAR1A and PeaTAR1B; which respond to tyramine by changing cAMP levels; is a major step towards understanding the actions of tyramine in cockroach physiology and behavior; particularly in comparison to the effects of octopamine. PMID:29084141

  17. PeaTAR1B: Characterization of a Second Type 1 Tyramine Receptor of the American Cockroach, Periplaneta americana.

    PubMed

    Blenau, Wolfgang; Balfanz, Sabine; Baumann, Arnd

    2017-10-30

    The catecholamines norepinephrine and epinephrine regulate important physiological functions in vertebrates. In insects; these neuroactive substances are functionally replaced by the phenolamines octopamine and tyramine. Phenolamines activate specific guanine nucleotide-binding (G) protein-coupled receptors (GPCRs). Type 1 tyramine receptors are better activated by tyramine than by octopamine. In contrast; type 2 tyramine receptors are almost exclusively activated by tyramine. Functionally; activation of type 1 tyramine receptors leads to a decrease in the intracellular concentration of cAMP ([cAMP] i ) whereas type 2 tyramine receptors can mediate Ca 2+ signals or both Ca 2+ signals and effects on [cAMP] i . Here; we report that the American cockroach ( Periplaneta americana ) expresses a second type 1 tyramine receptor (PeaTAR1B) in addition to PeaTAR1A (previously called PeaTYR1). When heterologously expressed in flpTM cells; activation of PeaTAR1B by tyramine leads to a concentration-dependent decrease in [cAMP] i . Its activity can be blocked by a series of established antagonists. The functional characterization of two type 1 tyramine receptors from P. americana ; PeaTAR1A and PeaTAR1B; which respond to tyramine by changing cAMP levels; is a major step towards understanding the actions of tyramine in cockroach physiology and behavior; particularly in comparison to the effects of octopamine.

  18. False promises: the tobacco industry, "low tar" cigarettes, and older smokers.

    PubMed

    Cataldo, Janine K; Malone, Ruth E

    2008-09-01

    To investigate the role of the tobacco industry in marketing to and sustaining tobacco addiction among older smokers and aging baby boomers, We performed archival searches of electronic archives of internal tobacco company documents using a snowball sampling approach. Analysis was done using iterative and comparative review of documents, classification by themes, and a hermeneutic interpretive approach to develop a case study. Based on extensive marketing research, tobacco companies aggressively targeted older smokers and sought to prevent them from quitting. Innovative marketing approaches were used. "Low tar" cigarettes were developed in response to the health concerns of older smokers, despite industry knowledge that such products had no health advantage and did not help smokers quit. Tobacco industry activities influence the context of cessation for older smokers in several ways. Through marketing "low tar" or "light" cigarettes to older smokers "at risk" of quitting, the industry contributes to the illusion that such cigarettes are safer, although "light" cigarettes may make it harder for addicted smokers to quit. Through targeted mailings of coupons and incentives, the industry discourages older smokers from quitting. Through rhetoric aimed at convincing addicted smokers that they alone are responsible for their smoking, the industry contributes to self-blame, a documented barrier to cessation. Educating practitioners, older smokers, and families about the tobacco industry's influence may decrease the tendency to "blame the victim," thereby enhancing the likelihood of older adults receiving tobacco addiction treatment. Comprehensive tobacco control measures must include a focus on older smokers.

  19. Leishmania, microbiota and sand fly immunity.

    PubMed

    Telleria, Erich Loza; Martins-da-Silva, Andrea; Tempone, Antonio Jorge; Traub-Csekö, Yara Maria

    2018-06-20

    In this review, we explore the state-of-the-art of sand fly relationships with microbiota, viruses and Leishmania, with particular emphasis on the vector immune responses. Insect-borne diseases are a major public health problem in the world. Phlebotomine sand flies are proven vectors of several aetiological agents including viruses, bacteria and the trypanosomatid Leishmania, which are responsible for diseases such as viral encephalitis, bartonellosis and leishmaniasis, respectively. All metazoans in nature coexist intimately with a community of commensal microorganisms known as microbiota. The microbiota has a fundamental role in the induction, maturation and function of the host immune system, which can modulate host protection from pathogens and infectious diseases. We briefly review viruses of public health importance present in sand flies and revisit studies done on bacterial and fungal gut contents of these vectors. We bring this information into the context of sand fly development and immune responses. We highlight the immunity mechanisms that the insect utilizes to survive the potential threats involved in these interactions and discuss the recently discovered complex interactions among microbiota, sand fly, Leishmania and virus. Additionally, some of the alternative control strategies that could benefit from the current knowledge are considered.

  20. A CFD model for biomass fast pyrolysis in fluidized-bed reactors

    NASA Astrophysics Data System (ADS)

    Xue, Qingluan; Heindel, T. J.; Fox, R. O.

    2010-11-01

    A numerical study is conducted to evaluate the performance and optimal operating conditions of fluidized-bed reactors for fast pyrolysis of biomass to bio-oil. A comprehensive CFD model, coupling a pyrolysis kinetic model with a detailed hydrodynamics model, is developed. A lumped kinetic model is applied to describe the pyrolysis of biomass particles. Variable particle porosity is used to account for the evolution of particle physical properties. The kinetic scheme includes primary decomposition and secondary cracking of tar. Biomass is composed of reference components: cellulose, hemicellulose, and lignin. Products are categorized into groups: gaseous, tar vapor, and solid char. The particle kinetic processes and their interaction with the reactive gas phase are modeled with a multi-fluid model derived from the kinetic theory of granular flow. The gas, sand and biomass constitute three continuum phases coupled by the interphase source terms. The model is applied to investigate the effect of operating conditions on the tar yield in a fluidized-bed reactor. The influence of various parameters on tar yield, including operating temperature and others are investigated. Predicted optimal conditions for tar yield and scale-up of the reactor are discussed.

  1. Evidence that a sequence similar to TAR is important for induction of the JC virus late promoter by human immunodeficiency virus type 1 Tat.

    PubMed Central

    Chowdhury, M; Taylor, J P; Chang, C F; Rappaport, J; Khalili, K

    1992-01-01

    A specific RNA sequence located in the leader of all human immunodeficiency virus type 1 (HIV-1) mRNAs termed the transactivation response element, or TAR, is a primary target for induction of HIV-1 long terminal repeat activity by the HIV-1-derived trans-regulatory protein, Tat. Human neurotropic virus, JC virus (JCV), a causative agent of the degenerative demyelinating disease progressive multifocal leukoencephalopathy, contains sequences in the 5' end of the late RNA species with an extensive homology to HIV-1 TAR. In this study, we examined the possible role of the JCV-derived TAR-homologous sequence in Tat-mediated activation of the JCV late promoter (Tada et al., Proc. Natl. Acad. Sci. USA 87:3479-3483, 1990). Results from site-directed mutagenesis revealed that critical G residues required for the function of HIV-1 TAR that are conserved in the JCV TAR homolog play an important role in Tat activation of the JCV promoter. In addition, in vivo competition studies suggest that shared regulatory components mediate Tat activation of the JCV late and HIV-1 long terminal repeat promoters. Furthermore, we showed that the JCV-derived TAR sequence behaves in the same way as HIV-1 TAR in response to two distinct Tat mutants, one of which that has no ability to bind to HIV-1 TAR and another that lacks transcriptional activity on a responsive promoter. These results suggest that the TAR homolog of the JCV late promoter is responsive to HIV-1 Tat induction and thus may participate in the overall activation of the JCV late promoter mediated by this transactivation. Images PMID:1331525

  2. LiDAR-Derived Flood-Inundation Maps for Real-Time Flood-Mapping Applications, Tar River Basin, North Carolina

    USGS Publications Warehouse

    Bales, Jerad D.; Wagner, Chad R.; Tighe, Kirsten C.; Terziotti, Silvia

    2007-01-01

    Flood-inundation maps were created for selected streamgage sites in the North Carolina Tar River basin. Light detection and ranging (LiDAR) data with a vertical accuracy of about 20 centimeters, provided by the Floodplain Mapping Information System of the North Carolina Floodplain Mapping Program, were processed to produce topographic data for the inundation maps. Bare-earth mass point LiDAR data were reprocessed into a digital elevation model with regularly spaced 1.5-meter by 1.5-meter cells. A tool was developed as part of this project to connect flow paths, or streams, that were inappropriately disconnected in the digital elevation model by such features as a bridge or road crossing. The Hydraulic Engineering Center-River Analysis System (HEC-RAS) model, developed by the U.S. Army Corps of Engineers, was used for hydraulic modeling at each of the study sites. Eleven individual hydraulic models were developed for the Tar River basin sites. Seven models were developed for reaches with a single gage, and four models were developed for reaches of the Tar River main stem that receive flow from major gaged tributaries, or reaches in which multiple gages were near one another. Combined, the Tar River hydraulic models included 272 kilometers of streams in the basin, including about 162 kilometers on the Tar River main stem. The hydraulic models were calibrated to the most current stage-discharge relations at 11 long-term streamgages where rating curves were available. Medium- to high-flow discharge measurements were made at some of the sites without rating curves, and high-water marks from Hurricanes Fran and Floyd were available for high-stage calibration. Simulated rating curves matched measured curves over the full range of flows. Differences between measured and simulated water levels for a specified flow were no more than 0.44 meter and typically were less. The calibrated models were used to generate a set of water-surface profiles for each of the 11 modeled

  3. SU-E-T-207: Comparison of Integrated Tissue Air Ratio (ITAR) to Traditional TAR for Kilovoltage Pencil-Beams

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hanlon, J; Koruga, I; Chell, E

    2015-06-15

    Purpose: Clinically viable depth dose determination in kilovoltage pencil-beams is a great challenge that resulted in a published dosimetry method called ITAR, which involves measurement of air kerma and attenuation with a detector in a low scatter environment coupled with MCNP scatter calculations. The objective of this work is to compare ITAR to traditional TAR using inherently water-proof microchambers that have only recently become commercially available. Methods: An Exradin A26 microchamber was centered 150 mm from a 100 kVp x-ray source with 2 mm aluminum HVL. Depth dose in water from 16 to 24 mm in 2 mm increments wasmore » determined by: (1) placing blocks of Plastic Water LR near the source to minimize scatter and using previously published conversion coefficients [ITAR method] and (2) submerging the detector in a water tank with 2 mm thick Plastic Water LR walls and jogging the tank with motor controllers while keeping the detector position fixed [traditional TAR method]. Each method was repeated four to five times. For each repetition, dose was measured free in-air to normalize the data for exponential regression. Results: Traditional TAR indicated higher depth dose than ITAR; differences ranged from 2.1% at 24 mm depth to 2.5% at 16 mm depth. However, the results of traditional TAR did not include a correction for Pq,cham because it is unknown for this detector type in these conditions. It is estimated that the component of Pq,cham due to the effect of water displacement alone is ∼0.94, but Pq,cham is likely several percent larger than 0.94 due to the energy dependency of the microchamber in the presence of low energy scatter that is not present during in-air calibration. Conclusion: The ITAR method remains preferable for clinical depth dose determination in kilovoltage pencil-beams due to Pq,cham being unknown for suitable detectors in relevant conditions. All four of the authors are either current full time employees, which include stock option

  4. Broadband Scattering from Sand and Sand/Mud Sediments with Extensive Environmental Characterization

    DTIC Science & Technology

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Broadband Scattering from Sand and Sand/ Mud Sediments...TERM GOALS To model the effects of volume heterogeneities, both discrete and continuous, in scattering from sand and mud sediments. A better...IMP2 has been used extensively during TREX13 and BayEx14 to measure the porosity in both sand and mud sediments. Analysis of this recent data inspired a

  5. Comparative carcinogenic potencies of particulates from diesel engine exhausts, coke oven emissions, roofing tar aerosols and cigarette smoke.

    PubMed Central

    Albert, R E

    1983-01-01

    Mammalian cell mutagenesis, transformation and skin tumorigenesis assays show similar results in comparing the potencies of diesel, coke oven, roofing tar and cigarette smoke particulates. These assay results are reasonably consistent with the comparative carcinogenic potencies of coke oven and roofing tar emissions as determined by epidemiological studies. The bacterial mutagenesis assay tends to show disproportionately high potencies, particularly with diesel particulates. Results to date encourage the approach to the assessment for carcinogenic risks from diesel emissions based on the use of epidemiological data on cancer induced by coke oven emissions, roofing tar particulates and cigarette smoke with the comparative potencies of these materials determined by in vivo and in vitro bioassays. PMID:6186481

  6. PAHs underfoot: contaminated dust from coal-tar sealcoated pavement is widespread in the United States

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Peter C. Van Metre; Barbara J. Mahler; Jennifer T. Wilson

    We reported in 2005 that runoff from parking lots treated with coal-tar-based sealcoat was a major source of polycyclic aromatic hydrocarbons (PAHs) to streams in Austin, Texas. Here we present new data from nine U.S. cities that show nationwide patterns in concentrations of {Sigma}PAHs associated with sealcoat. Dust was swept from parking lots in six cities in the central and eastern U.S., where coal-tar-based sealcoat dominates use, and three cities in the western U.S., where asphalt-based sealcoat dominates use. For six central and eastern cities, median SPAH concentrations in dust from sealcoated and unsealcoated pavement are 2200 and 27 mg/kg,more » respectively. For three western cities, median SPAH concentrations in dust from sealcoated and unsealcoated pavement are similar and very low (2.1 and 0.8 mg/kg, respectively). Lakes in the central and eastern cities where pavement was sampled have bottom sediments with higher PAH concentrations than do those in the western cities relative to degree of urbanization. Bottom-sediment PAH assemblages are similar to those of sealcoated pavement dust regionally, implicating coal-tar-based sealcoat as a PAH source to the central and eastern lakes. Concentrations of benzo(a)pyrene in dust from coal-tar sealcoated pavement and adjacent soils greatly exceed generic soil screening levels, suggesting that research on human-health risk is warranted. 30 refs., 4 figs., 2 tabs.« less

  7. Sand impaction of the small intestine in eight dogs.

    PubMed

    Moles, A D; McGhite, A; Schaaf, O R; Read, R

    2010-01-01

    To describe signalment, clinical findings, imaging and treatment of intestinal sand impaction in the dog. Medical records of dogs with radiographic evidence of small intestinal sand impaction were reviewed. Sand impaction resulting in small intestinal obstruction was diagnosed in eight dogs. All dogs presented with signs of vomiting. Other clinical signs included anorexia, lethargy and abdominal pain. Radiographs confirmed the presence of radio-opaque material consistent with sand causing distension of the terminal small intestine in all dogs. Four dogs were treated surgically for their impaction and four dogs were managed medically. Seven of the eight dogs survived. Both medical and surgical management of intestinal sand impaction in the dog can be effective and both afford a good prognosis for recovery.

  8. Invasive plants on disturbed Korean sand dunes

    NASA Astrophysics Data System (ADS)

    Kim, Kee Dae

    2005-01-01

    The sand dunes in coastal regions of South Korea are important ecosystems because of their small size, the rare species found in this habitat, and the beautiful landscapes they create. This study investigated the current vegetative status of sand dunes on three representative coasts of the Korean peninsula, and on the coasts of Cheju Island, and assessed the conditions caused by invasive plants. The relationships between the degree of invasion and 14 environmental variables were studied. Plots of sand dunes along line transects perpendicular to the coastal lines were established to estimate vegetative species coverage. TWINSPAN (Two-Way Indicator Species Analysis), CCA (Canonical Correspondence Analysis), and DCCA (Detrended Canonical Correspondence Analysis) were performed to classify communities on sand dunes and assess species composition variation. Carex kobomugi, Elymus mollis, and Vitex rotundifolia were found to be the dominant species plotted on the east, the west, and the peripheral coasts of Cheju Island, respectively. Vegetation on the south coast was totally extinct. The 19 communities, including representative C. kobomugi, C. kobomugi- Ixeris repens, C. kobomugi- Oenothera biennis, E. mollis, Lolium multiflorum- Calystegia soldanella, and V. rotundifolia- C. kobomugi, were all classified according to TWINSPAN. Oenothera biennis and L. multiflorum were exotics observed within these native communities. CCA showed that invasive native and exotic species distribution was segregated significantly, according to disturbance level, exotic species number, gravel, sand and silt contents, as well as vegetation size. It further revealed that human disturbance can strongly favor the settlement of invasive and exotic species. Restoration options to reduce exotic plants in the South Korean sand dune areas were found to be the introduction of native plant species from one sand dune into other sand dune areas, prohibition of building and the introduction of exotic

  9. Sand Filter Technology

    DTIC Science & Technology

    2016-08-01

    Approved for public release: distribution unlimited TDS-NAVFAC-EXWC-PW-1604 Aug 2016 Sand Filter Technology This report summarizes the...findings from a demonstration of sand filter technology to determine whether the technology will save energy with a simple payback within the...EXWC) performed the evaluation at the Naval Air Station Lemoore, CA. The two year evaluation period began with one year of sand filter operation

  10. Threshold for sand mobility on Mars calibrated from seasonal variations of sand flux.

    PubMed

    Ayoub, F; Avouac, J-P; Newman, C E; Richardson, M I; Lucas, A; Leprince, S; Bridges, N T

    2014-09-30

    Coupling between surface winds and saltation is a fundamental factor governing geological activity and climate on Mars. Saltation of sand is crucial for both erosion of the surface and dust lifting into the atmosphere. Wind tunnel experiments along with measurements from surface meteorology stations and modelling of wind speeds suggest that winds should only rarely move sand on Mars. However, evidence for currently active dune migration has recently accumulated. Crucially, the frequency of sand-moving events and the implied threshold wind stresses for saltation have remained unknown. Here we present detailed measurements of Nili Patera dune field based on High Resolution Imaging Science Experiment images, demonstrating that sand motion occurs daily throughout much of the year and that the resulting sand flux is strongly seasonal. Analysis of the seasonal sand flux variation suggests an effective threshold for sand motion for application to large-scale model wind fields (1-100 km scale) of τ(s)=0.01±0.0015 N m(-2).

  11. MultiMiTar: a novel multi objective optimization based miRNA-target prediction method.

    PubMed

    Mitra, Ramkrishna; Bandyopadhyay, Sanghamitra

    2011-01-01

    Machine learning based miRNA-target prediction algorithms often fail to obtain a balanced prediction accuracy in terms of both sensitivity and specificity due to lack of the gold standard of negative examples, miRNA-targeting site context specific relevant features and efficient feature selection process. Moreover, all the sequence, structure and machine learning based algorithms are unable to distribute the true positive predictions preferentially at the top of the ranked list; hence the algorithms become unreliable to the biologists. In addition, these algorithms fail to obtain considerable combination of precision and recall for the target transcripts that are translationally repressed at protein level. In the proposed article, we introduce an efficient miRNA-target prediction system MultiMiTar, a Support Vector Machine (SVM) based classifier integrated with a multiobjective metaheuristic based feature selection technique. The robust performance of the proposed method is mainly the result of using high quality negative examples and selection of biologically relevant miRNA-targeting site context specific features. The features are selected by using a novel feature selection technique AMOSA-SVM, that integrates the multi objective optimization technique Archived Multi-Objective Simulated Annealing (AMOSA) and SVM. MultiMiTar is found to achieve much higher Matthew's correlation coefficient (MCC) of 0.583 and average class-wise accuracy (ACA) of 0.8 compared to the others target prediction methods for a completely independent test data set. The obtained MCC and ACA values of these algorithms range from -0.269 to 0.155 and 0.321 to 0.582, respectively. Moreover, it shows a more balanced result in terms of precision and sensitivity (recall) for the translationally repressed data set as compared to all the other existing methods. An important aspect is that the true positive predictions are distributed preferentially at the top of the ranked list that makes MultiMiTar

  12. Analytical Determination of Nicotine and Tar Levels in Various Dokha and Shisha Tobacco Products.

    PubMed

    Mahboub, Bassam; Mohammad, Ayesha Begum; Nahlé, Ayssar; Vats, Mayank; Al Assaf, Omar; Al-Zarooni, Hamdan

    2018-05-10

    In the Middle East, there is no precise data and literature on tobacco-based products, such as dokha and shisha. The proposed study aims to quantify the levels of nicotine and tar in different kinds of dokha and shisha products that are sold in the local marketplace. The amount of nicotine in dokha and shisha products can be quantitatively determined using a combination of the "kissling" and "silicotungstic acid" method proposed by Robert M. Chapin. The tar residue from the smoke sample was collected on a glass wool placed before the stopcock (tap) of a separatory funnel as the smoke passes through the inlet of an electronically controlled vacuum pump. The nicotine levels in dokha and shisha samples ranged from 23.83 to 52.80 mg/g and 0.80 to 20.52 mg/g, respectively. The nicotine level varies between different tobacco products. It varies from 0.5 to 19.5 mg/g in cigarettes, from 10.3 to 23.1 mg/g in snuff tobacco, from 11 to 18 mg/g in electronic cigarettes and from 2.9 to 16.6 mg/g in chewing tobacco. The tar levels in the dokha and shisha samples ranged from 21.6 to 45.02 mg/g and 1.68 to 11.87 mg/g, respectively. Smokers are at a high risk of getting lung cancer, chronic obstructive pulmonary disease, emphysema and coronary artery disease owing to the high levels of nicotine and tar present in dokha and shisha tobacco products. These findings contradict the widespread belief among teenagers that dokha and shisha tobacco products are safer alternatives to cigarettes.

  13. Saltation of Non-Spherical Sand Particles

    PubMed Central

    Wang, Zhengshi; Ren, Shan; Huang, Ning

    2014-01-01

    Saltation is an important geological process and the primary source of atmospheric mineral dust aerosols. Unfortunately, no studies to date have been able to precisely reproduce the saltation process because of the simplified theoretical models used. For example, sand particles in most of the existing wind sand movement models are considered to be spherical, the effects of the sand shape on the structure of the wind sand flow are rarely studied, and the effect of mid-air collision is usually neglected. In fact, sand grains are rarely round in natural environments. In this paper, we first analyzed the drag coefficients, drag forces, and starting friction wind speeds of sand grains with different shapes in the saltation process, then established a sand saltation model that considers the coupling effect between wind and the sand grains, the effect of the mid-air collision of sand grains, and the effect of the sand grain shape. Based on this model, the saltation process and sand transport rate of non-spherical sand particles were simulated. The results show that the sand shape has a significant impact on the saltation process; for the same wind speed, the sand transport rates varied for different shapes of sand grains by as much as several-fold. Therefore, sand shape is one of the important factors affecting wind-sand movement. PMID:25170614

  14. Selected constituents in the smokes of foreign commercial cigaretts: tar, nicotine, carbon monoxide, and carbon dioxide

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jenkins, R.A.; Quincy, R.B.; Guerin, M.R.

    The tar, nicotine, carbon monoxide, and carbon dioxide contents of the smokes of 220 brands of foreign commercial cigarettes are reported. In some instances, filter cigarettes of certain brands were found to deliver as much or more smoke constituents than their nonfilter counterparts. Also, data indicated that there can be a great variation in the tar, nicotine, or carbon monoxide content of the smoke of samples of a given brand of cigarettes, depending on the nation in which they are purchased. 24 tables.

  15. Global sand trade is paving the way for a tragedy of the sand commons

    NASA Astrophysics Data System (ADS)

    Torres, A.; Brandt, J.; Lear, K.; Liu, J.

    2016-12-01

    In the first 40 years of the 21st century, planet Earth is highly likely to experience more urban land expansion than in all of history, an increase in transportation infrastructure by more than a third, and a great variety of land reclamation projects. While scientists are beginning to quantify the deep imprint of human infrastructure on biodiversity at large scales, its off-site impacts and linkages to sand mining and trade have been largely ignored. Sand is the most widely used building material in the world. With an ever-increasing demand for this resource, sand is being extracted at rates that far exceed its replenishment, and is becoming increasingly scarce. This has already led to conflicts around the world and will likely lead to a "tragedy of the sand commons" if sustainable sand mining and trade cannot be achieved. We investigate the environmental and socioeconomic interactions over large distances (telecouplings) of infrastructure development and sand mining and trade across diverse systems through transdisciplinary research and the recently proposed telecoupling framework. Our research is generating a thorough understanding of the telecouplings driven by an increasing demand for sand. In particular, we address three main research questions: 1) Where are the conflicts related to sand mining occurring?; 2) What are the major "sending" and "receiving" systems of sand?; and 3) What are the main components (e.g. causes, effects, agents, etc.) of telecoupled systems involving sand mining and trade? Our results highlight the role of global sand trade as a driver of environmental degradation that threatens the integrity of natural systems and their capacity to deliver key ecosystem services. In addition, infrastructure development and sand mining and trade have important implications for other sustainability challenges such as over-fishing and global warming. This knowledge will help to identify opportunities and tools to better promote a more sustainable use

  16. History of energy sources and their utilization in Nigeria

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ogunsola, O.I.

    1990-01-01

    Nigeria, a major oil producer, is rich in other energy sources. These include wood, coal, gas, tar sands, and hydro power. Although oil has been the most popular, some other energy sources have a longer history. This article discusses the historical trends in the production and utilization of Nigerian energy sources. Wood has the longest history. However,its utilization was limited to domestic cooking. Imported coal was first used in 1896, but it was not discovered in Nigeria until 1909 and was first produced in 1916. Although oil exploration started in 1901, it was first discovered in commercial quantity in 1956more » and produced in 1958. Oil thereafter took over the energy scene from coal until 1969, when hydro energy was first produced. Energy consumption has been mainly from hydro. Tar sands account for about 55% of total proven non-renewable reserves.« less

  17. Fabrication method and microstructural characteristics of coal-tar-pitch-based 2D carbon/carbon composites

    NASA Astrophysics Data System (ADS)

    Esmaeeli, Mohammad; Khosravi, Hamed; Mirhabibi, Alireza

    2015-02-01

    The lignin-cellulosic texture of wood was used to produce two-dimensional (2D) carbon/carbon (C/C) composites using coal tar pitch. Ash content tests were conducted to select two samples among the different kinds of woods present in Iran, including walnut, white poplar, cherry, willow, buttonwood, apricots, berry, and blue wood. Walnut and white poplar with ash contents of 1.994wt% and 0.351wt%, respectively, were selected. The behavior of these woods during pyrolysis was investigated by differential thermal analysis (DTA) and thermo gravimetric (TG) analysis. The bulk density and open porosity were measured after carbonization and densification. The microstructural characteristics of samples were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier-transform infrared (FT-IR) spectroscopy. The results indicate that the density of both the walnut and white poplar is increased, and the open porosity is decreased with the increasing number of carbonization cycles. The XRD patterns of the wood charcoal change gradually with increasing pyrolysis temperature, possibly as a result of the ultra-structural changes in the charcoal or the presence of carbonized coal tar pitch in the composite's body.

  18. 43 CFR 3140.6 - Use of additional lands.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... facilities in a Special Tar Sand Area that are needed to support any operations necessary for the recovery of... be filed at the time a plan of operations is filed. (b) A lease for the use of additional lands shall... include, but are not limited to, reservoirs, pipelines, electrical generation systems, transmission lines...

  19. Supply-Limited Bedforms in a Gravel-Sand Transition

    NASA Astrophysics Data System (ADS)

    Venditti, J. G.; Nittrouer, J. A.; Humphries, R. P.; Allison, M. A.

    2009-12-01

    Rivers often exhibit an abrupt transition from gravel to sand-bedded conditions as river channel slopes decrease. A distinct suite of bedforms has been observed through these reaches where sand supply to the bed is limited. The suite of bedforms includes a sequence of sand ribbons, barchans, and channel spanning dunes as sediment supply increases in the downstream direction. While these bedforms have been extensively documented in laboratory channels, there are relatively few observations of this sequence of supply-limited bedforms from large natural channels. Here we examine the sequence through the gravel-sand transition of the Fraser River in Southwestern British Columbia. We mapped the bed using multi-beam swath-bathymetry (Reson 8101 Seabat) at high flow (~9,000 m3s-1) immediately following a high peak flow of 11,800 m3s-1 in June 2007 The bed material grades from >70% gravel to entirely sand through the reach. The bedforms follow the expected sequence where sand ribbons and barchanoid forms cover the bed where it is primarily gravel. Channel spanning dunes form as the sand bed coverage increases. Bedform dimensions (height and length) increase moving downstream as the sand moving on the bed increases. Supply-unlimited bedforms typically scale with the flow depth where the height is 1/5 the flow depth. The bedforms developed over the gravel are undersized by this criterion. Downstream, where the bed is dominantly sand, bedforms do scale with flow depth. These data highlight the dominant role sediment supply can play in bedform morphology and scaling, confirming patterns observed in laboratory data.

  20. Microtox(TM) characterization of foundry sand residuals

    USGS Publications Warehouse

    Bastian, K.C.; Alleman, J.E.

    1998-01-01

    Although foundry residuals, consisting mostly of waste Sands, represent a potentially attractive, high-volume resource for beneficial reuse applications (e.g. highway embankment construction), prospective end users are understandably concerned about unforeseen liabilities stemming from the use of these residuals. This paper, therefore, focuses on the innovative use of a microbial bioassay as a means of developing a characterization of environmental suitability extending beyond the analytical coverage already provided by mandated chemical-specific tests (i.e., TCLP, etc.). Microtox(TM) bioassays were conducted on leachates derived from residuals obtained at a wide range of facilities, including: 11 gray and ductile iron foundries plus one each steel and aluminum foundries. In addition, virgin sand samples were used to establish a relative 'natural' benchmark against which the waste foundry sands could then be compared in terms of their apparent quality. These bioassay tests were able to effectively 'fingerprint' those residuals whose bioassay behavior was comparable to that of virgin materials. In fact, the majority of gray and ductile iron foundry residuals tested during this reported study elicited Microtox(TM) response levels which fell within or below the virgin sand response range, consequently providing another quantifiable layer of Support for this industry's claim that their sands are 'cleaner than dirt.' However, negative Microtox(TM) responses beyond that of the virgin sands were observed with a number of foundry samples (i.e. four of the 11 gray or ductile iron sands plus both non-iron sands). Therefore, the latter results would suggest that these latter residuals be excluded from beneficial reuse for the immediate future, at least until the cause and nature of this negative response has been further identified.

  1. Laboratory colonization and mass rearing of phlebotomine sand flies (Diptera, Psychodidae)

    PubMed Central

    Lawyer, Phillip; Killick-Kendrick, Mireille; Rowland, Tobin; Rowton, Edgar; Volf, Petr

    2017-01-01

    Laboratory colonies of phlebotomine sand flies are necessary for experimental study of their biology, behaviour and mutual relations with disease agents and for testing new methods of vector control. They are indispensable in genetic studies and controlled observations on the physiology and behaviour of sand flies, neglected subjects of high priority. Colonies are of particular value for screening insecticides. Colonized sand flies are used as live vector models in a diverse array of research projects, including xenodiagnosis, that are directed toward control of leishmaniasis and other sand fly-associated diseases. Historically, labour-intensive maintenance and low productivity have limited their usefulness for research, especially for species that do not adapt well to laboratory conditions. However, with growing interest in leishmaniasis research, rearing techniques have been developed and refined, and sand fly colonies have become more common, enabling many significant breakthroughs. Today, there are at least 90 colonies representing 21 distinct phlebotomine sand fly species in 35 laboratories in 18 countries worldwide. The materials and methods used by various sand fly workers differ, dictated by the availability of resources, cost or manpower constraints rather than choice. This paper is not intended as a comprehensive review but rather a discussion of methods and techniques most commonly used by researchers to initiate, establish and maintain sand fly colonies, with emphasis on the methods proven to be most effective for the species the authors have colonized. Topics discussed include collecting sand flies for colony stock, colony initiation, maintenance and mass-rearing procedures, and control of sand fly pathogens in colonies. PMID:29139377

  2. Direct multiplex PCR (dmPCR) for the identification of six Phlebotomine sand fly species (Diptera: Psychodidae), including major Leishmania vectors of the Mediterranean

    USDA-ARS?s Scientific Manuscript database

    Sand flies (Diptera: Psychodidae, subfamily Phlebotominae) are haematophagous insects that are known to transmit several anthroponotic and zoonotic diseases. Reliable identification of sand flies at species level is crucial for their surveillance, the detection and spread of their pathogens and the ...

  3. Direct Multiplex PCR (dmPCR) for the Identification of Six Phlebotomine Sand Fly Species (Diptera: Psychodidae), Including Major Leishmania Vectors of the Mediterranean.

    PubMed

    Giantsis, Ioannis A; Chaskopoulou, Alexandra; Claude Bon, Marie

    2017-02-01

    Sand flies (Diptera: Psychodidae, subfamily Phlebotominae) are hematophagous insects that are known to transmit several anthroponotic and zoonotic diseases. Reliable identification of sand flies at species level is crucial for their surveillance, the detection and spread of their pathogens, and the implementation of targeted pest control strategies. Here, we designed a novel, time-saving, cost-effective and easy-to-apply molecular methodology, which avoids sequencing, for the identification of the following six Eastern Mediterranean sand fly species: Phebotomus perfiliewi Parrot, Phebotomus simici Theodor, Phebotomus tobbi Adler and Theodor, Phebotomus papatasi Scopoli, Sergentomyia dentata Sinton, and Sergentomyia minuta Theodor. This methodology, which is a multiplex PCR assay using one common and six diagnostic primers, is based on species-specific single-nucleotide polymorphisms of the nuclear 18S rRNA gene. Amplification products were easily and reliably separated in agarose gel yielding one single clear band of diagnostic size for each species. Further, we verified its successful application on tissue samples that were immersed directly to the PCR mix, skipping DNA extraction. The direct multiplex PCR can be completed in < 3 h, including all operating procedures, and costing no more than a simple PCR. The applicability of this methodology in the detection of hybrids is an additional considerable benefit. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Rover Track in Sand Sheet Near Martian Sand Dune

    NASA Image and Video Library

    2015-12-10

    The rippled surface of the first Martian sand dune ever studied up close fills this view of "High Dune" from the Mast Camera (Mastcam) on NASA's Curiosity rover. This site is part of the "Bagnold Dunes" field along the northwestern flank of Mount Sharp. The dunes are active, migrating up to about one yard or meter per year. The component images of this mosaic view were taken on Nov. 27, 2015, during the 1,176th Martian day, or sol, of Curiosity's work on Mars. The scene is presented with a color adjustment that approximates white balancing, to resemble how the sand would appear under daytime lighting conditions on Earth. The annotated version includes superimposed scale bars of 30 centimeters (1 foot) in the foreground and 100 centimeters (3.3 feet) in the middle distance. Malin Space Science Systems, San Diego, built and operates Curiosity's Mastcam. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, built the rover and manages the project for NASA's Science Mission Directorate, Washington. http://photojournal.jpl.nasa.gov/catalog/PIA20169

  5. 43 CFR 3141.1 - General.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... may noncompetitively lease additional lands for ancillary facilities in a Special Tar Sand Area that are shown by an applicant to be needed to support any operations necessary for the recovery of tar... lease or permit to use additional lands shall be filed under the provisions of part 2920 of this title...

  6. 43 CFR 3141.1 - General.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... may noncompetitively lease additional lands for ancillary facilities in a Special Tar Sand Area that are shown by an applicant to be needed to support any operations necessary for the recovery of tar... lease or permit to use additional lands shall be filed under the provisions of part 2920 of this title...

  7. Cancer risk from incidental ingestion exposures to PAHs associated with coal-tar-sealed pavement

    USGS Publications Warehouse

    Williams, E. Spencer; Mahler, Barbara J.; Van Metre, Peter C.

    2012-01-01

    Recent (2009-10) studies documented significantly higher concentrations of polycyclic aromatic hydrocarbons (PAHs) in settled house dust in living spaces and soil adjacent to parking lots sealed with coal-tar-based products. To date, no studies have examined the potential human health effects of PAHs from these products in dust and soil. Here we present the results of an analysis of potential cancer risk associated with incidental ingestion exposures to PAHs in settings near coal-tar-sealed pavement. Exposures to benzo[a]pyrene equivalents were characterized across five scenarios. The central tendency estimate of excess cancer risk resulting from lifetime exposures to soil and dust from nondietary ingestion in these settings exceeded 1 × 10–4, as determined using deterministic and probabilistic methods. Soil was the primary driver of risk, but according to probabilistic calculations, reasonable maximum exposure to affected house dust in the first 6 years of life was sufficient to generate an estimated excess lifetime cancer risk of 6 × 10–5. Our results indicate that the presence of coal-tar-based pavement sealants is associated with significant increases in estimated excess lifetime cancer risk for nearby residents. Much of this calculated excess risk arises from exposures to PAHs in early childhood (i.e., 0–6 years of age).

  8. Tropospheric Emission Spectrometer (TES) Satellite Validations of Ammonia, Methanol, Formic Acid, and Carbon Monoxide over the Canadian Oil Sands

    EPA Pesticide Factsheets

    The URLs link to the data archive of the Troposphere Emission Spectrometer (TES) retrievals. These include the transects included in the Canadian Tar Sands study. A brief description of TES is listed below. TES is a spectrometer that measures the infrared-light energy (radiance) emitted by Earth's surface and by gases and particles in Earth's atmosphere. Every substance warmer than absolute zero emits infrared radiation at certain signature wavelengths. Spectrometers measure this radiation as a means of identifying the substances.TES has very high spectral resolution, which gives it the ability to pinpoint the wavelengths at which the substances are emitting. This enables precise identification of the substances, and also provides information about their location in the atmosphere. Emission wavelengths can vary with temperature and pressure, so seeing the emissions with great precision enables scientists to infer the temperature and pressure of the chemicals from which they came. This, in turn, implies that the chemicals being observed are at a certain altitude where those temperatures and pressures apply. The ability to determine the altitude of the observed chemicals enables TES to distinguish radiation from the upper and lower atmosphere, and focus on the lower layer - the troposphere.Since it observes light in the infrared range of the electromagnetic spectrum, similar to night-vision goggles, TES can observe both day and night. Its spectral range overlaps t

  9. Comprehensive GC²/MS for the monitoring of aromatic tar oil constituents during biodegradation in a historically contaminated soil.

    PubMed

    Vasilieva, Viktoriya; Scherr, Kerstin E; Edelmann, Eva; Hasinger, Marion; Loibner, Andreas P

    2012-02-20

    The constituents of tar oil comprise a wide range of physico-chemically heterogeneous pollutants of environmental concern. Besides the sixteen polycyclic aromatic hydrocarbons defined as priority pollutants by the US-EPA (EPA-PAHs), a wide range of substituted (NSO-PAC) and alkylated (alkyl-PAC) aromatic tar oil compounds are gaining increased attention for their toxic, carcinogenic, mutagenic and/or teratogenic properties. Investigations on tar oil biodegradation in soil are in part hampered by the absence of an efficient analytical tool for the simultaneous analysis of this wide range of compounds with dissimilar analytical properties. Therefore, the present study sets out to explore the applicability of comprehensive two-dimensional gas chromatography (GC²/MS) for the simultaneous measurement of compounds with differing polarity or that are co-eluting in one-dimensional systems. Aerobic tar oil biodegradation in a historically contaminated soil was analyzed over 56 days in lab-scale bioslurry tests. Forty-three aromatic compounds were identified with GC²/MS in one single analysis. The number of alkyl chains on a molecule was found to prime over alkyl chain length in hampering compound biodegradation. In most cases, substitution of carbon with nitrogen and oxygen was related to increased compound degradation in comparison to unalkylated and sulphur- or unsubstituted PAH with a similar ring number.The obtained results indicate that GC²/MS can be employed for the rapid assessment of a large variety of structurally heterogeneous environmental contaminants. Its application can contribute to facilitate site assessment, development and control of microbial cleanup technologies for tar oil contaminated sites. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Experimental investigation of cephapirin adsorption to quartz filter sands and dune sands

    NASA Astrophysics Data System (ADS)

    Peterson, Jonathan W.; O'Meara, Theresa A.; Seymour, Michael D.

    2008-08-01

    Batch experiments were performed to investigate cephapirin (a widely used veterinary antibiotic) adsorption on various size sands of low total organic carbon content (0.08-0.36 wt%). In the aqueous concentration range investigated (11-112 μmol/L cephapirin), adsorption to nearly pure quartz filter sands (0.50-3.35 mm diameter) is low. Isotherms are S-shaped and most display a region of minimum adsorption, where decreased adsorption occurs with increasing solution concentration, followed by increased adsorption at higher concentrations. Cephapirin adsorption to quartz-rich, feldspar-bearing dune sands (0.06-0.35 mm diameter), and the smallest quartz filter sand investigated (0.43-0.50 mm), can be described by linear sorption isotherms over the range of concentrations investigated. Distribution coefficients ( K d) range from 0.94 to 3.45 L/kg. No systematic relationship exists between grain size and amount of adsorption for any of the sands investigated. Cephapirin adsorption is positively correlated to the feldspar ratio (K-feldspar/(albite + Ca-plagioclase). Feldspar-ratio normalization of distribution coefficients was more effective than organic carbon normalization at reducing variability of K d values in the dune sands investigated.

  11. Sand pulses and sand patches on the Colorado River in Grand Canyon

    USGS Publications Warehouse

    Grams, Paul E.; Buscombe, Daniel; Topping, David; Mueller, Erich R.

    2017-01-01

    Alluvial sandbars occur in lateral recirculation zones (eddies) along the Colorado River in Grand Canyon National Park (Schmidt, 1990). Resource managers periodically release controlled floods from the upstream Glen Canyon Dam to rebuild these bars (Grams et al., 2015), which erode during fluctuating dam releases, and by hillslope runoff and wind deflation (Hazel et al., 2010). Because the dam blocks upstream sediment, episodic floods from tributaries provide the only supply to replace eroded sand; and much of this sand originates from a single tributary (Topping et al., 2000). Here, we present new evidence for the downstream translation of the sand component of these sediment inputs as discontinuous sand pulses. Improved understanding of the behaviour of these sand pulses may be used to adjust the timing, magnitude, and duration of controlled floods to maximize potential for deposition on sandbars in different segments of the 450 km-long Grand Canyon.

  12. Changes in tar yields and cigarette design in samples of Chinese cigarettes, 2009 and 2012

    PubMed Central

    Schneller, Liane M.; Zwierzchowski, Benjamin A.; Caruso, Rosalie V.; Li, Qiang; Yuan, Jiang; Fong, Geoffrey T.; O'Connor, Richard J.

    2015-01-01

    BACKGROUND China is home to both the greatest number of smokers and the greatest number of smoking-related deaths. An active and growing market of cigarettes marketed as “light” or “low tar” may keep health-concerned smokers from quitting, wrongly believing that such brands are less harmful. OBJECTIVE This study sought to observe changes in cigarette design characteristics and reported tar, nicotine and carbon monoxide (TNCO) levels in a sample of cigarette brands obtained in seven Chinese cities from 2009 and 2012. METHODS Cigarettes were purchased and shipped to Roswell Park Cancer Institute, where 91 pairs of packs were selected for physical cigarette design characteristic testing and recording of TNCO values. Data analysis was conducted using SPSS, and was initially characterized using descriptive statistics, correlations and generalized estimating equations to observe changes in brand varieties over time. FINDINGS Reported TNCO values on packs saw mean tar, nicotine and CO levels decrease from 2009 to 2012 by 7.9%, 4.5% and 6.0%, respectively. Ventilation was the only cigarette design feature that significantly changed over time (p < 0.001), with an increase of 31.7%. Significant predictors of tar and CO yields overall were ventilation and per-cigarette tobacco weight, while for nicotine tobacco moisture was also an independent predictor of yield. CONCLUSION The use of ventilation to decrease TNCO emissions is misleading smokers to believe that they are smoking a “light/low” tar cigarette that is healthier, and is potentially forestalling the quitting behaviors that would begin to reduce the health burden of tobacco in China, and so should be prohibited. PMID:25352560

  13. Association of daily tar and nicotine intake with incident myocardial infarction: Results from the population-based MONICA/KORA Augsburg Cohort Study 1984 - 2002

    PubMed Central

    2011-01-01

    Background Cigarette smoking has been shown to be one of the most important risk factors for cardiovascular diseases. However, little is known about cumulative effects of daily tar and nicotine intake on the risk of incident myocardial infarction (MI) so far. To bridge this gap, we conducted an analysis in a large prospective study from Southern Germany investigating associations of daily tar and nicotine intake with an incident MI event. Methods The study was based on 4,099 men and 4,197 women participating in two population-based MONICA Augsburg surveys between 1984 and 1990 and followed up within the KORA framework until 2002. During a mean follow-up of 13.3 years, a number of 307 men and 80 women developed an incident MI event. Relative risks were calculated as hazard ratios (HRs) estimated by Cox proportional hazards models adjusted for cardiovascular risk factors. Results In the present study, male regular smokers consumed on average more cigarettes per day than female regular smokers (20 versus 15) and had a higher tar and nicotine intake per day. In men, the MI risk compared to never-smokers increased with higher tar intake: HRs were 2.24 (95% CI 1.40-3.56) for 1-129 mg/day, 2.12 (95% CI 1.37-3.29) for 130-259 mg/day and 3.01 (95% CI 2.08-4.36) for ≥ 260 mg/day. In women, the corresponding associations were comparable but more pronounced for high tar intake (HR 4.67, 95% CI 1.76-12.40). Similar associations were observed for nicotine intake. Conclusions The present study based on a large population-based sample adds important evidence of cumulative effects of tar and nicotine intake on the risk of incident MI. Even low or medium tar and nicotine intake revealed substantial risk increases as compared to never-smokers. Therefore, reduction of tar and nicotine contents in cigarettes cannot be seen as a suitable public health policy in preventing myocardial infarction. PMID:21542909

  14. Analysis of pure tar substances (polycyclic aromatic hydrocarbons) in the gas stream using ultraviolet visible (UV-Vis) spectroscopy and multivariate curve resolution (MCR).

    PubMed

    Weide, Tobias; Guschin, Viktor; Becker, Wolfgang; Koelle, Sabine; Maier, Simon; Seidelt, Stephan

    2015-01-01

    The analysis of tar, mostly characterized as polycyclic aromatic hydrocarbons (PAHs), describes a topic that has been researched for years. An online analysis of tar in the gas stream in particular is needed to characterize the tar conversion or formation in the biomass gasification process. The online analysis in the gas is carried out with ultraviolet-visible (UV-Vis) spectroscopy (190-720 nm). This online analysis is performed with a measuring cell developed by the Fraunhofer Institute for Chemical Technology (ICT). To this day, online tar measurements using UV-Vis spectroscopy have not been carried out in detail. Therefore, PAHs are analyzed as follows. The measurements are split into different steps. The first step to prove the online method is to vaporize single tar substances. These experiments show that a qualitative analysis of PAHs in the gas stream with the used measurement setup is possible. Furthermore, it is shown that the method provides very exact results, so that a differentiation of various PAHs is possible. The next step is to vaporize a PAH mixture. This step consists of vaporizing five pure substances almost simultaneously. The interpretation of the resulting data is made using a chemometric interpretation method, the multivariate curve resolution (MCR). The verification of the calculated results is the main aim of this experiment. It has been shown that the tar mixture can be analyzed qualitatively and quantitatively (in arbitrary units) in detail using the MCR. Finally it is the main goal of this paper to show the first steps in the applicability of the UV-Vis spectroscopy and the measurement setup on online tar analysis in view of characterizing the biomass gasification process. Due to that, the gasification plant (at the laboratory scale), developed and constructed by the Fraunhofer ICT, has been used to vaporize these substances. Using this gasification plant for the experiments enables the usage of the measurement setup also for the

  15. A combined CFD-experimental method for developing an erosion equation for both gas-sand and liquid-sand flows

    NASA Astrophysics Data System (ADS)

    Mansouri, Amir

    The surface degradation of equipment due to consecutive impacts of abrasive particles carried by fluid flow is called solid particle erosion. Solid particle erosion occurs in many industries including oil and gas. In order to prevent abrupt failures and costly repairs, it is essential to predict the erosion rate and identify the locations of the equipment that are mostly at risk. Computational Fluid Dynamics (CFD) is a powerful tool for predicting the erosion rate. Erosion prediction using CFD analysis includes three steps: (1) obtaining flow solution, (2) particle tracking and calculating the particle impact speed and angle, and (3) relating the particle impact information to mass loss of material through an erosion equation. Erosion equations are commonly generated using dry impingement jet tests (sand-air), since the particle impact speed and angle are assumed not to deviate from conditions in the jet. However, in slurry flows, a wide range of particle impact speeds and angles are produced in a single slurry jet test with liquid and sand particles. In this study, a novel and combined CFD/experimental method for developing an erosion equation in slurry flows is presented. In this method, a CFD analysis is used to characterize the particle impact speed, angle, and impact rate at specific locations on the test sample. Then, the particle impact data are related to the measured erosion depth to achieve an erosion equation from submerged testing. Traditionally, it was assumed that the erosion equation developed based on gas testing can be used for both gas-sand and liquid-sand flows. The erosion equations developed in this work were implemented in a CFD code, and CFD predictions were validated for various test conditions. It was shown that the erosion equation developed based on slurry tests can significantly improve the local thickness loss prediction in slurry flows. Finally, a generalized erosion equation is proposed which can be used to predict the erosion rate in

  16. Controls on the abruptness of gravel-sand transitions

    NASA Astrophysics Data System (ADS)

    Venditti, J. G.; Church, M. A.; Lamb, M. P.; Domarad, N.; Rennie, C. D.

    2014-12-01

    As gravel-bedded rivers fine downstream, they characteristically exhibit an abrupt transition from gravel- to sand-bed. This is the only abrupt transition in grain-size that occurs in the fluvial system and has attracted considerable attention. A number of competing theories have been proposed to account for the abruptness of the transition, including base-level control, attrition of ~10mm gravel to produce sand, and sediment sorting processes. The prevailing theory for the emergence of abrupt transitions is size selective sorting of bimodal sediment wherein gravel deposits due to downstream declining shear stress, fining the bedload until a sand-bed emerges. We explored this hypothesis by examining grain-size, shear stress, gravel mobility and sand suspension thresholds through the gravel-sand transition (GST) of the Fraser River, British Columbia. The Fraser GST is an arrested gravel wedge with patches of gravel downstream of the wedge forming a diffuse extension. There is an abrupt change in bed slope through the transition that leads to an abrupt change in shear stress. The GST, bed-slope change and backwater caused by the ocean are all coincident spatially, which enhances the sharpness of the GST. Interestingly, the bimodal reach of the river occurs downstream of the GST and exhibits no downstream gradients in shear stress, suspended sediment flux, gravel mobility or sand suspension thresholds. This calls into question the prevailing theory for the emergence of an abrupt GST by size selective sorting. We provide evidence, both empirical and theoretical, that suggests the emergence of an abrupt GST is caused by rapid deposition of sand when fine gravel deposits. We argue that the emergence of gravel-sand transitions is a consequence of gravel-bedded rivers adopting a steeper slope than sand-bedded rivers. The abruptness arises because the bed slope required to convey the gravel load fixes the distal location of a terminal gravel wedge, and once the river has

  17. Monitoring Sand Sheets and Dunes

    NASA Image and Video Library

    2017-06-12

    NASA's Mars Reconnaissance Orbiter (MRO) captured this crater featuring sand dunes and sand sheets on its floor. What are sand sheets? Snow fall on Earth is a good example of sand sheets: when it snows, the ground gets blanketed with up to a few meters of snow. The snow mantles the ground and "mimics" the underlying topography. Sand sheets likewise mantle the ground as a relatively thin deposit. This kind of environment has been monitored by HiRISE since 2007 to look for movement in the ripples covering the dunes and sheets. This is how scientists who study wind-blown sand can track the amount of sand moving through the area and possibly where the sand came from. Using the present environment is crucial to understanding the past: sand dunes, sheets, and ripples sometimes become preserved as sandstone and contain clues as to how they were deposited The map is projected here at a scale of 25 centimeters (9.8 inches) per pixel. [The original image scale is 25 centimeters (9.8 inches) per pixel (with 1 x 1 binning); objects on the order of 75 centimeters (29.5 inches) across are resolved.] North is up. https://photojournal.jpl.nasa.gov/catalog/PIA21757

  18. Relationship of respiratory symptoms and pulmonary function to tar, nicotine, and carbon monoxide yield of cigarettes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Krzyzanowski, M.; Sherrill, D.L.; Paoletti, P.

    The data from consecutive surveys of the Tucson Epidemiologic Study (1981-1988) were used to evaluate the relationship in cigarette smokers of respiratory symptoms and pulmonary function to tar, nicotine, and carbon monoxide (CO) yields of the cigarette. There were 690 subjects who reported smoking regularly in at least one survey, over age 15. After adjustment for intensity and duration of smoking and for depth of inhalation, the risk of chronic phlegm, cough, and dyspnea were not related to the tar and nicotine yields. In 414 subjects with pulmonary function tested in at least one of the three surveys the spirometricmore » indices used were significantly related to the daily dose of tar, nicotine, and CO (product of the cigarette yield and daily number of cigarettes smoked). The effects were more pronounced for past than for current doses. However, the differentiation of pulmonary function due to various yields of cigarettes was small in comparison to the difference in pulmonary function between smokers and nonsmokers.« less

  19. Adsorption of nicotine and tar from the mainstream smoke of cigarettes by oxidized carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Chen, Zhigang; Zhang, Lisha; Tang, Yiwen; Jia, Zhijie

    2006-02-01

    The adsorption of nicotine and tar from the mainstream smoke (MS) by the filter tips filled respectively with oxidized carbon nanotubes (O-CNTs), activated carbon and zeolite (NaY) has been investigated. O-CNTs show exceptional removal efficiency and their adsorption mechanism is investigated. Capillary condensation of some ingredients from MS in the inner hole of O-CNTs is observed and may be the primary reason for their superior removal efficiency. The effect of O-CNTs mass on the removal efficiencies is also studied and the results show that about 20-30 mg O-CNTs per cigarette can effectively remove most of nicotine and tar.

  20. Altitude of the top of the Sparta Sand and Memphis Sand in three areas of Arkansas

    USGS Publications Warehouse

    Pugh, Aaron L.; Westerfield, Paul W.; Gonthier, Gerard; Poynter, David T.

    1998-01-01

    The Sparta Sand and Memphis Sand form the second most productive aquifer in Arkansas. The Sparta Sand and Memphis Sand range in thick- ness from 0 to 900 feet, consisting of fine- to medium-grained sands interbedded with layers of silt, clay, shale, and minor amounts of lignite. Within the three areas of interest, the top surface of the Sparta Sand and Memphis Sand dips regionally east and southeast towards the axis of the Mississippi Embayment syncline and Desha Basin. Local variations in the top surface may be attributed to a combination of continued development of structural features, differential compaction, localized faulting, and erosion of the surface prior to subsequent inundation and deposition of younger sediments.

  1. 48 CFR 1201.301-70 - Amendment of (TAR) 48 CFR chapter 12.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Amendment of (TAR) 48 CFR chapter 12. 1201.301-70 Section 1201.301-70 Federal Acquisition Regulations System DEPARTMENT OF TRANSPORTATION GENERAL FEDERAL ACQUISITION REGULATIONS SYSTEM Agency Acquisition Regulations 1201.301-70...

  2. 48 CFR 1201.301-70 - Amendment of (TAR) 48 CFR chapter 12.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Amendment of (TAR) 48 CFR chapter 12. 1201.301-70 Section 1201.301-70 Federal Acquisition Regulations System DEPARTMENT OF TRANSPORTATION GENERAL FEDERAL ACQUISITION REGULATIONS SYSTEM Agency Acquisition Regulations 1201.301-70...

  3. 48 CFR 1201.301-70 - Amendment of (TAR) 48 CFR chapter 12.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Amendment of (TAR) 48 CFR chapter 12. 1201.301-70 Section 1201.301-70 Federal Acquisition Regulations System DEPARTMENT OF TRANSPORTATION GENERAL FEDERAL ACQUISITION REGULATIONS SYSTEM Agency Acquisition Regulations 1201.301-70...

  4. 48 CFR 1201.301-70 - Amendment of (TAR) 48 CFR chapter 12.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Amendment of (TAR) 48 CFR chapter 12. 1201.301-70 Section 1201.301-70 Federal Acquisition Regulations System DEPARTMENT OF TRANSPORTATION GENERAL FEDERAL ACQUISITION REGULATIONS SYSTEM Agency Acquisition Regulations 1201.301-70...

  5. Oxygenated Interface on Biomass Burn Tar Balls Determined bySingle Particle Scanning Transmission X-ray Microscopy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tivanski, A.V.; Hopkins, R.J.; Tyliszczak, T.

    2007-06-21

    Carbonaceous particles originating from biomass burning canaccount for a large fraction of organic aerosols in a local environment.Presently, their composition, physical and chemical properties, as wellas their environmental effects are largely unknown. Tar balls, a distincttype of highly spherical carbonaceous biomass burn particles, have beenobserved in a number of field campaigns. The Yosemite AerosolCharacterization Study that took place in summer 2002 occurred during anactive fire season in the western United States; tar balls collectedduring this field campaign are described in this article. Scanningtransmission X-ray microscopy and near-edge X-ray absorption finestructure spectroscopy are used to determine the shape, structure, andsize-dependent chemicalmore » composition of ~;150 individual sphericalparticles ranging in size from 0.15 to 1.2mu m.The elemental compositionof tar balls is ~;55 percent atomic carbon and ~;45 percent atomicoxygen. Oxygen is present primarily as carboxylic carbonyls andoxygen-substituted alkyl (O-alkyl-C) functional groups, followed bymoderate amounts of ketonic carbonyls. The observed chemical composition,density, and carbon functional groups are distinctly different from sootor black carbon and more closely resemble high molecular weight polymerichumic-like substances, which could account for their reported opticalproperties. A detailed examination of the carboxylic carbonyl andO-alkyl-C functional groups as a function of particle size reveals a thinoxygenated interface layer. The high oxygen content, as well as thepresence of water-soluble carboxylic carbonyl groups, could account forthe reported hygroscopic properties of tar balls. The presence of theoxygenated layer is attributed to atmospheric processing of biomass burnparticles.« less

  6. Coal-Tar-Based Parking Lot Sealcoat: An Unrecognized Source of PAH to Settled House Dust

    PubMed Central

    2010-01-01

    Despite much speculation, the principal factors controlling concentrations of polycyclic aromatic hydrocarbons (PAH) in settled house dust (SHD) have not yet been identified. In response to recent reports that dust from pavement with coal-tar-based sealcoat contains extremely high concentrations of PAH, we measured PAH in SHD from 23 apartments and in dust from their associated parking lots, one-half of which had coal-tar-based sealcoat (CT). The median concentration of total PAH (T-PAH) in dust from CT parking lots (4760 μg/g, n = 11) was 530 times higher than that from parking lots with other pavement surface types (asphalt-based sealcoat, unsealed asphalt, concrete [median 9.0 μg/g, n = 12]). T-PAH in SHD from apartments with CT parking lots (median 129 μg/g) was 25 times higher than that in SHD from apartments with parking lots with other pavement surface types (median 5.1 μg/g). Presence or absence of CT on a parking lot explained 48% of the variance in log-transformed T-PAH in SHD. Urban land-use intensity near the residence also had a significant but weaker relation to T-PAH. No other variables tested, including carpeting, frequency of vacuuming, and indoor burning, were significant. PMID:20063893

  7. Two-fold sustainability – Adobe with sawdust as partial sand replacement

    NASA Astrophysics Data System (ADS)

    Jokhio, Gul A.; Syed Mohsin, Sharifah M.; Gul, Yasmeen

    2018-04-01

    Adobe is a material that is economic, environment friendly, and provides better indoor air quality. The material required for the preparation of adobe include clay, sand, and sometimes straw or other organic materials. These materials do not require industrial processing or transportation, however, sand mining has been recently posing a threat to the environment. Therefore, to enhance the existing sustainability of adobe, sand can be partially or fully replaced by other waste materials. This approach will not only solve the problem of excessive sand mining, it will also address the issue of waste management. Sawdust is one such waste material that can be used to partially replace sand in Adobe. This paper presents the results of compressive and flexural test carried out on Adobe samples with partial sand replacement by sawdust. The results show that about 4% sand replacement by volume produces higher compressive strength, whereas the flexural strength reduces with the use of sawdust. However, since flexural strength is not a critical property for adobe, it is concluded that replacing sand with sawdust by about 4% of volume will be beneficial.

  8. Simultaneous recovery and desulfurization of bitumen from oil sand using ultrasound irradiation

    NASA Astrophysics Data System (ADS)

    Okawa, Hirokazu; Kamal, Wan Mohamad Ikhwan bin Wan; Akazawa, Nobuyuki; Kato, Takahiro; Sugawara, Katsuyasu

    2018-07-01

    Oil sand contains bitumen, which includes a high percentage of sulfur. Before using bitumen as a fuel, it must be recovered from oil sand and desulfurized. Currently, bitumen is recovered from oil sand using hot water (<100 °C), and sulfur is removed via hydrodesulfurization (>300 °C). Both of these processes consume significant amounts of energy. In this study, we demonstrate the simultaneous recovery and desulfurization of bitumen from oil sand using oxidative desulfurization with ultrasonic irradiation and tetrahydrofuran at 20 °C. We successfully recovered 88% of the bitumen from oil sand and removed 42% of the sulfur from the bitumen.

  9. Sydney tar ponds: some problems in quantifying toxic waste.

    PubMed

    Furimsky, Edward

    2002-12-01

    Information on the type and amount of hazardous and toxic waste is required to develop a meaningful strategy and estimate a realistic cost for clean up of the Sydney Tar Pond site which is located on Cape Breton, in the province of Nova Scotia, Canada. The site covers the area of the decommissioned Sysco (Sydney Steel Corporation) plant. The materials of concern include BTEX (benzene, toluene, ethylbenzene, and xylenes), PAH (polycyclic aromatic hydrocarbons), PCB (polychlorinated biphenyl), and particulates laden with toxic metals, such as arsenic, lead, and others. The originally nontoxic materials such as soil, blast furnace slag, and vegetation, as well as surface and ground waters, which were subsequently contaminated, must also be included if they fail tests prescribed by environmental regulations. An extensive sampling program must be undertaken to obtain data for an accurate estimate of the waste to be cleaned and disposed of. Apparently, 700,000 tons of toxic waste, which is believed to be present on the site, may represent only a fraction of the actual amount. The clean-up of the site is only part of the solution. Toxic waste has to be disposed of in accordance with environmental regulations.

  10. Non-Natural Linker Configuration in 2,6-Dipeptidyl-Anthraquinones Enhances the Inhibition of TAR RNA Binding/Annealing Activities by HIV-1 NC and Tat Proteins.

    PubMed

    Sosic, Alice; Saccone, Irene; Carraro, Caterina; Kenderdine, Thomas; Gamba, Elia; Caliendo, Giuseppe; Corvino, Angela; Di Vaio, Paola; Fiorino, Ferdinando; Magli, Elisa; Perissutti, Elisa; Santagada, Vincenzo; Severino, Beatrice; Spada, Valentina; Fabris, Dan; Frecentese, Francesco; Gatto, Barbara

    2018-06-12

    The HIV-1 nucleocapsid (NC) protein represents an excellent molecular target for the development of anti-retrovirals by virtue of its well-characterized chaperone activities, which play pivotal roles in essential steps of the viral life cycle. Our ongoing search for candidates able to impair NC binding/annealing activities led to the identification of peptidyl-anthraquinones as a promising class of nucleic acid ligands. Seeking to elucidate the inhibition determinants and increase the potency of this class of compounds, we have now explored the effects of chirality in the linker connecting the planar nucleus to the basic side chains. We show here that the non-natural linker configuration imparted unexpected TAR RNA targeting properties to the 2,6-peptidyl-anthraquinones and significantly enhanced their potency. Even if the new compounds were able to interact directly with the NC protein, they manifested a consistently higher affinity for the TAR RNA substrate and their TAR-binding properties mirrored their ability to interfere with NC-TAR interactions. Based on these findings, we propose that the viral Tat protein, sharing the same RNA substrate but acting in distinct phases of the viral life cycle, constitutes an additional druggable target for this class of peptidyl-anthraquinones. The inhibition of Tat-TAR interaction for the test compounds correlated again with their TAR-binding properties, while simultaneously failing to demonstrate any direct Tat-binding capabilities. These considerations highlighted the importance of TAR RNA in the elucidation of their inhibition mechanism, rather than direct protein inhibition. We have therefore identified anti-TAR compounds with dual in vitro inhibitory activity on different viral proteins, demonstrating that it is possible to develop multitarget compounds capable of interfering with processes mediated by the interactions of this essential RNA domain of HIV-1 genome with NC and Tat proteins.

  11. Flow resistance and suspended load in sand-bed rivers: Simplified stratification model

    USGS Publications Warehouse

    Wright, S.; Parker, G.

    2004-01-01

    New methods are presented for the prediction of the flow depth, grain-size specific near-bed concentration, and bed-material suspended sediment transport rate in sand-bed rivers. The salient improvements delineated here all relate to the need to modify existing formulations in order to encompass the full range of sand-bed rivers, and in particular large, low-slope sand-bed rivers. They can be summarized as follows: (1) the inclusion of density stratification effects in a simplified manner, which have been shown in the companion paper to be particularly relevant for large, low-slope, sand-bed rivers; (2) a new predictor for near-bed entrainment rate into suspension which extends a previous relation to the range of large, low-slope sand-bed rivers; and (3) a new predictor for form drag which again extends a previous relation to include large, low-slope sand-bed rivers. Finally, every attempt has been made to cast the relations in the simplest form possible, including the development of software, so that practicing engineers may easily use the methods. ?? ASCE.

  12. Fecal indicators in sand, sand contact, and risk of enteric illness among beach-goers

    EPA Science Inventory

    BACKGROUND: Beach sand can harbor fecal indicator organisms and pathogens, but enteric illness risk associated with sand contact remains unclear. METHODS: In 2007, visitors at 2 recreational marine beaches were asked on the day of their visit about sand contact. Ten to 12 days...

  13. Constitutive Soil Properties for Unwashed Sand and Kennedy Space Center

    NASA Technical Reports Server (NTRS)

    Thomas, Michael A.; Chitty, Daniel E.; Gildea, Martin L.; T'Kindt, Casey M.

    2008-01-01

    Accurate soil models are required for numerical simulations of land landings for the Orion Crew Exploration Vehicle. This report provides constitutive material models for one soil, unwashed sand, from NASA Langley's gantry drop test facility and three soils from Kennedy Space Center (KSC). The four soil models are based on mechanical and compressive behavior observed during geotechnical laboratory testing of remolded soil samples. The test specimens were reconstituted to measured in situ density and moisture content. Tests included: triaxial compression, hydrostatic compression, and uniaxial strain. A fit to the triaxial test results defines the strength envelope. Hydrostatic and uniaxial tests define the compressibility. The constitutive properties are presented in the format of LS-DYNA Material Model 5: Soil and Foam. However, the laboratory test data provided can be used to construct other material models. The four soil models are intended to be specific to the soil conditions discussed in the report. The unwashed sand model represents clayey sand at high density. The KSC models represent three distinct coastal sand conditions: low density dry sand, high density in-situ moisture sand, and high density flooded sand. It is possible to approximate other sands with these models, but the results would be unverified without geotechnical tests to confirm similar soil behavior.

  14. Sand Pine Symposium Proceedings

    Treesearch

    USDA Forest Service Southern Forest Experiment Station

    1973-01-01

    Sand pine, a species well suited to the excessively drained soils common to several million acres in the Southeast, was the subject of this well-attended 3-day meeting. Papers presented included a review of the literature plus results of current research related to this species. Subjects covered ranged from seeds and seedlings to final harvest and conversion...

  15. Yields of tar, nicotine, and carbon monoxide in the sidestream smoke from 15 brands of Canadian cigarettes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rickert, W.S.; Robinson, J.C.; Collishaw, N.

    Sidestream smoke yields for 15 brands of cigarettes were determined under conditions where mainstream yields were approximately equal to those used for determining the values which appear on packages of Canadian cigarettes. Sidestream yields of tar, nicotine, and carbon monoxide were much higher than mainstream yields for all brands tested. The average sidestream-to-mainstream ratios for the 15 brands were 3.5, 6.6, and 6.8 for tar, nicotine, and carbon monoxide, respectively. The highest yields of sidestream were obtained from the brands with the lowest mainstream yields.

  16. Booming Sand Dunes

    NASA Astrophysics Data System (ADS)

    Vriend, Nathalie

    "Booming" sand dunes are able to produce low-frequency sound that resembles a pure note from a music instrument. The sound has a dominant audible frequency (70-105 Hz) and several higher harmonics and may be heard from far distances away. A natural or induced avalanche from a slip face of the booming dune triggers the emission that may last for several minutes. There are various references in travel literature to the phenomenon, but to date no scientific explanation covered all field observations. This thesis introduces a new physical model that describes the phenomenon of booming dunes. The waveguide model explains the selection of the booming frequency and the amplification of the sound in terms of constructive interference in a confined geometry. The frequency of the booming is a direct function of the dimensions and velocities in the waveguide. The higher harmonics are related to the higher modes of propagation in the waveguide. The experimental validation includes quantitative field research at the booming dunes of the Mojave Desert and Death Valley National Park. Microphone and geophone recordings of the acoustic and seismic emission show a variation of booming frequency in space and time. The analysis of the sensor data quantifies wave propagation characteristics such as speed, dispersion, and nonlinear effects and allows the distinction between the source mechanism of the booming and the booming itself. The migration of sand dunes results from a complicated interplay between dune building, wind regime, and precipitation. The morphological and morphodynamical characteristics of two field locations are analyzed with various geophysical techniques. Ground-penetrating radar images the subsurface structure of the dunes and reveal a natural, internal layering that is directly related to the history of dune migration. The seismic velocity increases abruptly with depth and gradually increases with downhill position due to compaction. Sand sampling shows local

  17. The impact of steam and current density on carbon formation from biomass gasification tar on Ni/YSZ, and Ni/CGO solid oxide fuel cell anodes

    NASA Astrophysics Data System (ADS)

    Mermelstein, Joshua; Millan, Marcos; Brandon, Nigel

    The combination of solid oxide fuel cells (SOFCs) and biomass gasification has the potential to become an attractive technology for the production of clean renewable energy. However the impact of tars, formed during biomass gasification, on the performance and durability of SOFC anodes has not been well established experimentally. This paper reports an experimental study on the mitigation of carbon formation arising from the exposure of the commonly used Ni/YSZ (yttria stabilized zirconia) and Ni/CGO (gadolinium-doped ceria) SOFC anodes to biomass gasification tars. Carbon formation and cell degradation was reduced through means of steam reforming of the tar over the nickel anode, and partial oxidation of benzene model tar via the transport of oxygen ions to the anode while operating the fuel cell under load. Thermodynamic calculations suggest that a threshold current density of 365 mA cm -2 was required to suppress carbon formation in dry conditions, which was consistent with the results of experiments conducted in this study. The importance of both anode microstructure and composition towards carbon deposition was seen in the comparison of Ni/YSZ and Ni/CGO anodes exposed to the biomass gasification tar. Under steam concentrations greater than the thermodynamic threshold for carbon deposition, Ni/YSZ anodes still exhibited cell degradation, as shown by increased polarization resistances, and carbon formation was seen using SEM imaging. Ni/CGO anodes were found to be more resilient to carbon formation than Ni/YSZ anodes, and displayed increased performance after each subsequent exposure to tar, likely due to continued reforming of condensed tar on the anode.

  18. Provenance and recycling of Arabian desert sand

    NASA Astrophysics Data System (ADS)

    Garzanti, Eduardo; Vermeesch, Pieter; Andò, Sergio; Vezzoli, Giovanni; Valagussa, Manuel; Allen, Kate; Kadi, Khalid; Al-Juboury, Ali

    2013-04-01

    This study seeks to determine the ultimate origin of aeolian sand in Arabian deserts by high-resolution petrographic and heavy-mineral techniques combined with zircon U-Pb geochronology. Point-counting is used here as the sole method by which unbiased volume percentages of heavy minerals can be obtained. A comprehensive analysis of river and wadi sands from the Red Sea to the Bitlis-Zagros orogen allowed us to characterize all potential sediment sources, and thus to quantitatively constrain provenance of Arabian dune fields. Two main types of aeolian sand can be distinguished. Quartzose sands with very poor heavy-mineral suites including zircon occupy most of the region comprising the Great Nafud and Rub' al-Khali Sand Seas, and are largely recycled from thick Lower Palaeozoic quartzarenites with very minor first-cycle contributions from Precambrian basement, Mesozoic carbonate rocks, or Neogene basalts. Instead, carbonaticlastic sands with richer lithic and heavy-mineral populations characterize coastal dunes bordering the Arabian Gulf from the Jafurah Sand Sea of Saudi Arabia to the United Arab Emirates. The similarity with detritus carried by the axial Tigris-Euphrates system and by transverse rivers draining carbonate rocks of the Zagros indicates that Arabian coastal dunes largely consist of far-travelled sand, deposited on the exposed floor of the Gulf during Pleistocene lowstands and blown inland by dominant Shamal northerly winds. A dataset of detrital zircon U-Pb ages measured on twelve dune samples and two Lower Palaeozoic sandstones yielded fourteen identical age spectra. The age distributions all show a major Neoproterozoic peak corresponding to the Pan-African magmatic and tectonic events by which the Arabian Shield was assembled, with minor late Palaeoproterozoic and Neoarchean peaks. A similar U-Pb signature characterizes also Jafurah dune sands, suggesting that zircons are dominantly derived from interior Arabia, possibly deflated from the Wadi al

  19. Provenance and recycling of Arabian desert sand

    NASA Astrophysics Data System (ADS)

    Garzanti, Eduardo; Vermeesch, Pieter; Andò, Sergio; Vezzoli, Giovanni; Valagussa, Manuel; Allen, Kate; Kadi, Khalid A.; Al-Juboury, Ali I. A.

    2013-05-01

    This study seeks to determine the ultimate origin of aeolian sand in Arabian deserts by high-resolution petrographic and heavy-mineral techniques combined with zircon U-Pb geochronology. Point-counting is used here as the sole method by which unbiased volume percentages of heavy minerals can be obtained. A comprehensive analysis of river and wadi sands from the Red Sea to the Bitlis-Zagros orogen allowed us to characterize all potential sediment sources, and thus to quantitatively constrain provenance of Arabian dune fields. Two main types of aeolian sand can be distinguished. Quartzose sands with very poor heavy-mineral suites including zircon occupy most of the region comprising the Great Nafud and Rub' al-Khali Sand Seas, and are largely recycled from thick Lower Palaeozoic quartzarenites with very minor first-cycle contributions from Precambrian basement, Mesozoic carbonate rocks, or Neogene basalts. Instead, carbonaticlastic sands with richer lithic and heavy-mineral populations characterize coastal dunes bordering the Arabian Gulf from the Jafurah Sand Sea of Saudi Arabia to the United Arab Emirates. The similarity with detritus carried by the axial Tigris-Euphrates system and by transverse rivers draining carbonate rocks of the Zagros indicates that Arabian coastal dunes largely consist of far-travelled sand, deposited on the exposed floor of the Gulf during Pleistocene lowstands and blown inland by dominant Shamal northerly winds. A dataset of detrital zircon U-Pb ages measured on twelve dune samples and two Lower Palaeozoic sandstones yielded fourteen identical age spectra. The age distributions all show a major Neoproterozoic peak corresponding to the Pan-African magmatic and tectonic events by which the Arabian Shield was assembled, with minor late Palaeoproterozoic and Neoarchean peaks. A similar U-Pb signature characterizes also Jafurah dune sands, suggesting that zircons are dominantly derived from interior Arabia, possibly deflated from the Wadi al

  20. Industrial sand and gravel

    USGS Publications Warehouse

    Dolley, T.P.

    2006-01-01

    In 2005, domestic production of industrial sand and gravel was about 31 Mt, a 5% increase from 2004. This increase was bouyed by robust construction and petroleum sectors of the US economy. Based on estimated world production figures, the United States was the world's leading producer and consumer of industrial sand and gravel. In the short term, local shortages of industrial sand and gravel will continue to increase.

  1. Geologic map of Great Sand Dunes National Park, Colorado

    USGS Publications Warehouse

    Madole, Richard F.; VanSistine, D. Paco; Romig, Joseph H.

    2016-10-20

    Geologic mapping was begun after a range fire swept the area of what is now the Great Sand Dunes National Park in April 2000. The park spans an area of 437 square kilometers (or about 169 square miles), of which 98 percent is blanketed by sediment of Quaternary age, the Holocene and Pleistocene Epochs; hence, this geologic map of the Great Sand Dunes National Park is essentially a surficial geologic map. These surficial deposits are diverse and include sediment of eolian (windblown), alluvial (stream and sheetwash), palustrine (wetlands and marshes), lacustrine (lake), and mass-wasting (landslides) origin. Sediment of middle and late Holocene age, from about 8,000 years ago to the present, covers about 80 percent of the park.Fluctuations in groundwater level during Holocene time caused wetlands on the nearby lowland that bounds the park on the west to alternately expand and contract. These fluctuations controlled the stability or instability of eolian sand deposits on the downwind (eastern) side of the lowland. When groundwater level rose, playas became lakes, and wet or marshy areas formed in many places. When the water table rose, spring-fed streams filled their channels and valley floors with sediment. Conversely, when groundwater level fell, spring-fed streams incised their valley floors, and lakes, ponds, and marshes dried up and became sources of windblown sand.Discharge in streams draining the west flank of the Sangre de Cristo Range is controlled primarily by snowmelt and flow is perennial until it reaches the mountain front, beyond which streams begin losing water at a high rate as the water soaks into the creek beds. Even streams originating in the larger drainage basins, such as Sand and Medano Creeks, generally do not extend much more than 4 km (about 2.5 miles) beyond where they exit the mountains.The Great Sand Dunes contain the tallest dunes (maximum height about 750 feet, or 230 m) in North America. These dunes cover an area of 72 square kilometers

  2. [Environmental toxicity of waste foundry sand].

    PubMed

    Zhang, Hai-Feng; Wang, Yu-Jue; Wang, Jin-Lin; Huang, Tian-You; Xiong, Ying

    2013-03-01

    The metal leaching characteristics and volatile organic compounds (VOCs) of five different types of waste foundry sands were analyzed with the toxicity characteristic leaching procedure (TCLP) and head space-gas chromatography (HS-GC). Microtox and soil dehydrogenase activity (DHA) tests were then used to evaluate the bio-effects of these waste sands. The results showed that due to the different metals poured and casting materials used to make the sand molds, there was significant difference among the five waste foundry sands in the compositions and concentrations of metal and organic pollutants. The concentrations of Fe in the leachates of iron and steel casting waste foundry sand exceeded the maximal allowable concentrations specified in the National Standard of Drinking Water Quality, whereas the As concentration in the leachate of aluminum casting waste foundry sand exceeded the standard. The five waste foundry sands had quite different compositions and levels of VOCs, which resulted in different levels of inhibition effects on the luminescent bacteria (30% and 95%). Additionally, the soil DHA tests suggested that metal pollutants in waste foundry sands may inhibit the soil microbial activity, whereas organics in the sands may slightly promote the microbial activity. The results of this study indicated that the waste foundry sands may pose considerable threat to the environment when improperly disposed.

  3. Compressive behavior of fine sand.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Martin, Bradley E.; Kabir, Md. E.; Song, Bo

    2010-04-01

    The compressive mechanical response of fine sand is experimentally investigated. The strain rate, initial density, stress state, and moisture level are systematically varied. A Kolsky bar was modified to obtain uniaxial and triaxial compressive response at high strain rates. A controlled loading pulse allows the specimen to acquire stress equilibrium and constant strain-rates. The results show that the compressive response of the fine sand is not sensitive to strain rate under the loading conditions in this study, but significantly dependent on the moisture content, initial density and lateral confinement. Partially saturated sand is more compliant than dry sand. Similar trendsmore » were reported in the quasi-static regime for experiments conducted at comparable specimen conditions. The sand becomes stiffer as initial density and/or confinement pressure increases. The sand particle size become smaller after hydrostatic pressure and further smaller after dynamic axial loading.« less

  4. Overview of the technology and status of oil sands development

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Detamore, R.J.

    1981-01-01

    In conjunction with the increasing emphasis upon alternate energy sources, interest in the oil sands resource is discussed. This paper reviews the primary established oil sands recovery techniques including surface mining, surface retorting, in situ thermal and nonthermal in situ, and presents an overview of their application in specific projects.

  5. Bilaterally cleft lip, limb defects, and haematological manifestations: Roberts syndrome versus TAR syndrome.

    PubMed

    Urban, M; Opitz, C; Bommer, C; Enders, H; Tinschert, S; Witkowski, R

    1998-09-23

    We report on a 13-year-old patient followed since birth. He is the only offspring of young, non-consanguineous German parents. His mother has an isolated left cleft of lip and a cleft palate. At birth, our patient presented with bilaterally cleft lip/cleft palate, phocomelia of upper limbs with normal hands, and mild symmetrical deficiencies of the long bones of the lower limbs. Haematological evaluation demonstrated a leukaemoid reaction during a urinary tract infection as well as intermittent thrombocytopenia and episodes of marked eosinophilia during the first two years of life. Intellectual development has been normal. Comparison with two similar cases from the literature suggests a non-random phenotypic overlap of Roberts syndrome (MIM 268300) and TAR syndrome (MIM 274000). Such clinical constellations may be key observations to understand the genetic relationship of Roberts syndrome and TAR syndrome in future phenotype-genotype correlations.

  6. Simulation of groundwater flow in the "1,500-foot" sand and "2,000-foot" sand and movement of saltwater in the "2,000-foot" sand of the Baton Rouge area, Louisiana

    USGS Publications Warehouse

    Heywood, Charles E.; Griffith, Jason M.

    2013-01-01

    Groundwater withdrawals have caused saltwater to encroach into freshwater-bearing aquifers beneath Baton Rouge, Louisiana. Groundwater investigations in the 1960s identified a freshwater-saltwater interface located at the Baton Rouge Fault, across which abrupt changes in water levels occur. Aquifers south of the fault generally contain saltwater, and aquifers north of the fault contain freshwater, though limited saltwater encroachment has been detected within 7 of the 10 aquifers north of the fault. The 10 aquifers beneath the Baton Rouge area, which includes East and West Baton Rouge Parishes, Pointe Coupee Parish, and East and West Feliciana Parishes, provided about 167 million gallons per day (Mgal/day) for public supply and industrial use in 2010. Groundwater withdrawals from an aquifer that is 2,000-feet (ft) deep in East Baton Rouge Parish (the “2,000-foot” sand of the Baton Rouge area) have caused water-level drawdown up to 356 ft and induced saltwater movement northward across the fault. Groundwater withdrawals from the “2,000-foot” sand averaged 23.9 Mgal/d during 2010. Saltwater encroachment threatens wells that are located about 3 miles north of the fault, where industrial withdrawals account for about 66 percent of the water withdrawn from the “2,000-foot” sand in East Baton Rouge Parish. Constant and variable-density groundwater models were developed with the MODFLOW and SEAWAT groundwater modeling codes to evaluate strategies to control saltwater migration, including changes in the distribution of groundwater withdrawals and installation of “scavenger” wells to intercept saltwater before it reaches existing production wells. Five hypothetical scenarios simulated the effects of different groundwater withdrawal options on groundwater levels within the “1,500-foot” sand and the “2,000-foot” sand and the transport of saltwater within the “2,000-foot” sand. Scenario 1 is considered a base case for comparison to the other four

  7. Windblown Sand in Ganges Chasma

    NASA Image and Video Library

    2017-04-25

    Dark, windblown sand covers intricate sedimentary rock layers in this image captured by NASA's Mars Reconnaissance Orbiter (MRO) from Ganges Chasma, a canyon in the Valles Marineris system. These features are at once familiar and unusual to those familiar with Earth's beaches and deserts. Most sand dunes on Earth are made of silica-rich sand, giving them a light color; these Martian dunes owe their dark color to the iron and magnesium-rich sand found in the region. https://photojournal.jpl.nasa.gov/catalog/PIA21600

  8. Epoxy-borax-coal tar composition for a radiation protective, burn resistant drum liner and centrifugal casting method

    DOEpatents

    Taylor, Robert S.; Boyer, Norman W.

    1980-01-01

    A boron containing burn resistant, low level radiation protection material useful, for example, as a liner for radioactive waste disposal and storage, a component for neutron absorber, and a shield for a neutron source. The material is basically composed of Borax in the range of 25-50%, coal tar in the range of 25-37.5%, with the remainder being an epoxy resin mix. A preferred composition is 50% Borax, 25% coal tar and 25% epoxy resin. The material is not susceptible to burning and is about 1/5 the cost of existing radiation protection material utilized in similar applications.

  9. Epoxy-borax-coal tar composition for a radiation protective, burn resistant drum liner and centrifugal casting method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Boyer, N.W.; Taylor, R.S.

    1980-10-28

    A boron containing burn resistant, low level radiation protection material useful, for example, as a liner for radioactive waste disposal and storage, a component for neutron absorber, and a shield for a neutron source. The material is basically composed of borax in the range of 25-50%, coal tar in the range of 25-37.5%, with the remainder being an epoxy resin mix. A preferred composition is 50% borax, 25% coal tar and 25% epoxy resin. The material is not susceptible to burning and is about 1/5 the cost of existing radiation protection material utilized in similar applications.

  10. Pesticides in streams in the Tar-Pamlico drainage basin, North Carolina, 1992-94

    USGS Publications Warehouse

    Woodside, Michael D.; Ruhl, Kelly E.

    2001-01-01

    From 1992 to 1994, 147 water samples were collected at 5 sites in the Tar-Pamlico drainage basin in North Carolina and analyzed for 46 herbicides, insecticides, and pesticide metabolites as part of the U.S. Geological Survey's National Water-Quality Assessment Program. Based on a common adjusted detection limit of 0.01 microgram per liter, the most frequently detected herbicides were metolachlor (84 percent), atrazine (78 percent), alachlor (72 percent), and prometon (57 percent). The insecticides detected most frequently were carbaryl (12 percent), carbofuran (7 percent), and diazinon (4 percent). Although the pesticides with the highest estimated uses generally were the compounds detected most frequently, there was not a strong correlation between estimated use and detection frequency. The development of statistical correlations between pesticide use and detection frequency was limited by the lack of information on pesticides commonly applied in urban and agricultural areas, such as prometon, chlorpyrifos, and diazinon, and the small number of basins included in this study. For example, prometon had the fourth highest detection frequency, but use information was not available. Nevertheless, the high detection frequency of prometon indicates that nonagricultural uses also contribute to pesticide levels in streams in the Tar-Pamlico drainage basin.Concentrations of the herbicides atrazine, alachlor, and trifluralin varied seasonally, with elevated concentrations generally occurring in the spring, during and immediately following application periods, and in the summer. Seasonal concentration patterns were less evident for prometon, diazinon, and chlorpyrifos. Alachlor is the only pesticide detected in concentrations that exceeded current (2000) drinking-water standards.

  11. Industrial sand and gravel

    USGS Publications Warehouse

    Dolley, T.P.

    2010-01-01

    Domestic production of industrial sand and gravel in 2009 was about 27 Mt (30 million st), declining by 10 percent compared with 2008. Certain end uses of industrial sand and gravel, such as foundry and glassmaking sand, may have declined by a factor greater than 10 percent in 2009. U.S. apparent consumption was 24.7 Mt (27.2 million st) in 2009, down by 10 percent from the previous year, and imports declined to 83 kt (91,000 st).

  12. A High Resolution Look at Black Sand Particles from Sand Dunes of Saudi Arabia Using Electron Microscopy

    NASA Astrophysics Data System (ADS)

    Hussain, M. M.; Aburizaiza, O. S.; Siddique, A.; Hershey, D. L.; Guerrieri, D. A.; Qurashi, J.; Abbass, M.; Blake, D. R.; Khwaja, H. A.

    2013-12-01

    Particulate air pollution is a problem of health concern. The microscopic make-up of different varieties of sand particles found and collected at a sand dune site in Badr, Saudi Arabia has been determined. Primary emphasis is given to the use of multiple high resolution electron microscopy (viz., Scanning Electron Microscopy with Energy Dispersive X-ray spectrometry (SEM/EDS) and Laser Scanning Microscopy (LSM)) to study the morphologies, emission source types, size, and elemental composition of the particles, and to evaluate the presence of ';coatings or contaminants' adsorbed or carried on by the black sand particles. White sand contains natural coarse particles associated with wind-blown releases from crustal surfaces, weathering of an igneous/metamorphic rock source, and volcanic activities. Silicates (alumino-silicates) and quartz (clear, milky, rose) dominate white sand and rest appears to contain calcite, olivine, feldspar, and magnetite. Black sand particles exhibit very different morphologies and microstructures (surface roughness) compared with white sand and volcanic ash. Morphological analyses have shown that the black sand contain ultrafine particles. Black sand is strongly magnetic, which indicates the mineral magnetite (strongly magnetic) or elemental iron. Iron, C, O, Ti, Si, V, and S particles dominate the black sand. Natural and anthropogenic sources have been implicated for the observed particles. Analysis revealed that the surface of white sand particles is mainly covered with the fine particles. It is known that emissions from combustion contain carbon soot and other contaminants that are easily absorbed by soil particles during a long-range transport.

  13. The Geodiversity in Drift Sand Landscapes of The Netherlands

    NASA Astrophysics Data System (ADS)

    van den Ancker, Hanneke; Jungerius, Pieter Dirk; Riksen, Michel

    2015-04-01

    metres high. They are common near villages. They originated through sand blown from fallow agricultural fields and local overgrazing. They vary in age from prehistoric to modern time and are now mostly planted with forests. Third are the linear drift sand areas with one to three metre high ridges that align old roads and originated through dust whirled up by horses and carriages over many centuries. They also occurs within drift sands of the first system. In the re-stabilization of reactivated drift sands, differences in geodiversity on a still more detailed scale are important (Ancker, Jungerius et al. 2013). Even a small change in slope can cause primary dunes to develop and stop wind erosion. Gradually the geodiversity aspects are recognized as relevant for the management of active and fossil drift sands, and also is becoming a management issue in itself. An important future research issue is the completion of the Drift Sand Atlas, a project that describes the geodiversity aspects of all drift sand areas of The Netherlands. This project has been retarded by lack of means. Knowledge of the geodiversity also is important for correct sampling of C14 and luminescence data. Other future research includes the processes that caused the formation of 'randwallen' (rim walls), rates of water and wind erosion and soil formation and links between flora, fauna and Natura 2000 species. References

  14. Structural determinants of HIV-1 nucleocapsid protein for cTAR DNA binding and destabilization, and correlation with inhibition of self-primed DNA synthesis.

    PubMed

    Beltz, Hervé; Clauss, Céline; Piémont, Etienne; Ficheux, Damien; Gorelick, Robert J; Roques, Bernard; Gabus, Caroline; Darlix, Jean-Luc; de Rocquigny, Hugues; Mély, Yves

    2005-05-20

    The nucleocapsid protein (NC) of human immunodeficiency virus type 1 (HIV-1) is formed of two highly conserved CCHC zinc fingers flanked by small basic domains. NC is required for the two obligatory strand transfers in viral DNA synthesis through its nucleic acid chaperoning properties. The first DNA strand transfer relies on NC's ability to bind and destabilize the secondary structure of complementary transactivation response region (cTAR) DNA, to inhibit self-priming, and to promote the annealing of cTAR to TAR RNA. To further investigate NC chaperone properties, our aim was to identify by fluorescence spectroscopy and gel electrophoresis, the NC structural determinants for cTAR binding and destabilization, and for the inhibition of self-primed DNA synthesis on a model system using a series of NC mutants and HIV-1 reverse transcriptase. NC destabilization and self-priming inhibition properties were found to be supported by the two fingers in their proper context and the basic (29)RAPRKKG(35) linker. The strict requirement of the native proximal finger suggests that its hydrophobic platform (Val13, Phe16, Thr24 and Ala25) is crucial for binding, destabilization and inhibition of self-priming. In contrast, only partial folding of the distal finger is required, probably for presenting the Trp37 residue in an appropriate orientation. Also, Trp37 and the hydrophobic residues of the proximal finger appear to be essential for the propagation of the melting from the cTAR ends up to the middle of the stem. Finally, both N-terminal and C-terminal basic domains contribute to cTAR binding but not to its destabilization.

  15. Risk factors for faecal sand excretion in Icelandic horses.

    PubMed

    Husted, L; Andersen, M S; Borggaard, O K; Houe, H; Olsen, S N

    2005-07-01

    Sandy soil is often mentioned as a risk factor in the development of sand-related gastrointestinal disease (SGID) in the horse. There are other variables, but few studies confirm any of these. To investigate soil type, pasture quality, feeding practice in the paddock, age, sex and body condition score as risk factors for sand intake in the horse. Faeces were collected from 211 Icelandic horses on 19 different studs in Denmark together with soil samples and other potential risk factors. Sand content in faeces determined by a sand sedimentation test was interpreted as evidence of sand intake. Soil types were identified by soil analysis and significance of the data was tested using logistic analysis. Of horses included in the study, 56.4% showed sand in the faeces and 5.7% had more than 5 mm sand as quantified by the rectal sleeve sedimentation test. Soil type had no significant effect when tested as main effect, but there was interaction between soil type and pasture quality. Significant interactions were also found between paddock feeding practice and pasture quality. To evaluate the risk of sand intake it is important to consider 3 variables: soil type, pasture quality and feeding practice. Pasture quality was identified as a risk factor of both short and long grass in combination with sandy soil, while clay soil had the lowest risk in these combinations. Feeding practice in the paddock revealed feeding directly on the ground to be a risk factor when there was short (1-5 cm) or no grass. Also, no feeding outdoors increased the risk on pastures with short grass, while this had no effect in paddocks with no grass. More than 50% of all horses investigated in this study had sand in the faeces. The identification of risk factors is an important step towards prevention of SGID. Further research is necessary to determine why some horses exhibit more than 5 mm sand in the sedimentation test and whether this is correlated with geophagic behaviour.

  16. The region preceding the C-terminal NWETF pentapeptide modulates baseline activity and aspartate inhibition of Escherichia coli Tar.

    PubMed

    Lai, Run-Zhi; Bormans, Arjan F; Draheim, Roger R; Wright, Gus A; Manson, Michael D

    2008-12-16

    The Tar chemoreceptor-CheA-CheW ternary complex of Escherichia coli is a transmembrane allosteric enzyme in which binding of ligands to the periplasmic domain modulates the activity of CheA kinase. Kinase activity is also affected by reversible methylation of four glutamyl residues in the cytoplasmic domain of the receptor. E. coli Tar contains 553 residues. Residues 549-553 comprise the NWETF pentapeptide that binds the CheR methyltransferase and CheB methylesterase. The crystal structure of the similar Tsr chemoreceptor predicts that residues 263-289 and 490-515 of Tar form the most membrane-proximal portion of the extended CD1-CD2 four-helix bundle of the cytoplasmic domain. The last methylation site, Glu-491, is in the C19 heptad, and the N22-19 and C22-19 heptads are present in all classes of bacterial transmembrane chemoreceptors. Residues 516-548 probably serve as a flexible tether for the NWETF pentapeptide. Here, we present a mutational analysis of residues 505-548. The more of this region that is deleted, the less sensitive Tar is to inhibition by aspartate. Tar deleted from residue 505 through the NWETF sequence stimulates CheA in vitro but is not inhibited by aspartate. Thus, interaction of the last two heptads (C21 and C22) of CD2 with the first two heptads (N22 and N21) of CD1 must be important for transmitting an inhibitory signal from the HAMP domain to the four-helix bundle. The R514A, K523A, R529A, R540A, and R542A substitutions, singly or together, increase the level of activation of CheA in vitro, whereas the R505A substitution decreases the level of CheA stimulation by 40% and lowers the aspartate K(i) 7-fold. The R505E substitution completely abolishes stimulation of CheA in vitro. Glu-505 may interact electrostatically with Asp-273 to destabilize the "on" signaling state by loosening the four-helix bundle.

  17. Coal-tar-based sealcoated pavement: a major PAH source to urban stream sediments.

    PubMed

    Witter, Amy E; Nguyen, Minh H; Baidar, Sunil; Sak, Peter B

    2014-02-01

    We used land-use analysis, PAH concentrations and assemblages, and multivariate statistics to identify sediment PAH sources in a small (~1303 km(2)) urbanizing watershed located in South-Central, Pennsylvania, USA. A geographic information system (GIS) was employed to quantify land-use features that may serve as PAH sources. Urban PAH concentrations were three times higher than rural levels, and were significantly and highly correlated with combined residential/commercial/industrial land use. Principal components analysis (PCA) was used to group sediments with similar PAH assemblages, and correlation analysis compared PAH sediment assemblages to common PAH sources. The strongest correlations were observed between rural sediments (n = 7) and coke-oven emissions sources (r = 0.69-0.78, n = 5), and between urban sediments (n = 22) and coal-tar-based sealcoat dust (r = 0.94, n = 47) suggesting that coal-tar-based sealcoat is an important urban PAH source in this watershed linked to residential and commercial/industrial land use. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Microbial strengthening of loose sand.

    PubMed

    Banagan, B L; Wertheim, B M; Roth, M J S; Caslake, L F

    2010-08-01

    To test whether the addition of Flavobacterium johnsoniae could increase the strength of saturated Ottawa 30 sand. A box model was built that simulates groundwater-like flow through a main sand compartment. Strength tests were performed at seven locations and at two depths, 10.8 and 20.3 cm below the top of the tank, using a vane shear device before and after the addition of bacteria. After the addition of Fl. johnsoniae, sand samples were obtained from multiple sampling ports on the vertical sides of the box model. The presence of a bacterial biofilm was confirmed by staining these sand samples with SYTO-9 and Alexa Fluor 633 and viewing with a confocal microscope. The average shear strength increases after the addition of Fl. johnsoniae were 15.2-87.5%, depending on the experimental conditions. Flavobacterium johnsoniae caused a statistically significant increase in the strength of saturated Ottawa 30 sand. Biofilm-forming bacteria can increase the shear strength of saturated sand. The addition of biofilm-forming bacteria to a building site may be an alternate method to mitigate the effects of liquefaction.

  19. Biomass waste gasification - Can be the two stage process suitable for tar reduction and power generation?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sulc, Jindrich; Stojdl, Jiri; Richter, Miroslav

    2012-04-15

    Highlights: Black-Right-Pointing-Pointer Comparison of one stage (co-current) and two stage gasification of wood pellets. Black-Right-Pointing-Pointer Original arrangement with grate-less reactor and upward moving bed of the pellets. Black-Right-Pointing-Pointer Two stage gasification leads to drastic reduction of tar content in gas. Black-Right-Pointing-Pointer One stage gasification produces gas with higher LHV at lower overall ER. Black-Right-Pointing-Pointer Content of ammonia in gas is lower in two stage moving bed gasification. - Abstract: A pilot scale gasification unit with novel co-current, updraft arrangement in the first stage and counter-current downdraft in the second stage was developed and exploited for studying effects of two stagemore » gasification in comparison with one stage gasification of biomass (wood pellets) on fuel gas composition and attainable gas purity. Significant producer gas parameters (gas composition, heating value, content of tar compounds, content of inorganic gas impurities) were compared for the two stage and the one stage method of the gasification arrangement with only the upward moving bed (co-current updraft). The main novel features of the gasifier conception include grate-less reactor, upward moving bed of biomass particles (e.g. pellets) by means of a screw elevator with changeable rotational speed and gradual expanding diameter of the cylindrical reactor in the part above the upper end of the screw. The gasifier concept and arrangement are considered convenient for thermal power range 100-350 kW{sub th}. The second stage of the gasifier served mainly for tar compounds destruction/reforming by increased temperature (around 950 Degree-Sign C) and for gasification reaction of the fuel gas with char. The second stage used additional combustion of the fuel gas by preheated secondary air for attaining higher temperature and faster gasification of the remaining char from the first stage. The measurements of gas composition

  20. PAHs underfoot: contaminated dust from coal-tar sealcoated pavement is widespread in the United States.

    PubMed

    Van Metre, Peter C; Mahler, Barbara J; Wilson, Jennifer T

    2009-01-01

    We reported in 2005 that runoff from parking lots treated with coal-tar-based sealcoat was a major source of polycyclic aromatic hydrocarbons (PAHs) to streams in Austin, Texas. Here we present new data from nine U.S. cities that show nationwide patterns in concentrations of PAHs associated with sealcoat. Dust was swept from parking lots in six cities in the central and eastern U.S., where coal-tar-based sealcoat dominates use, and three cities in the western U.S., where asphalt-based sealcoat dominates use. For six central and eastern cities, median SigmaPAH concentrations in dust from sealcoated and unsealcoated pavement are 2200 and 27 mg/kg, respectively. For three western cities, median SigmaPAH concentrations in dust from sealcoated and unsealcoated pavement are similar and very low (2.1 and 0.8 mg/kg, respectively). Lakes in the central and eastern cities where pavement was sampled have bottom sediments with higher PAH concentrations than do those in the western cities relative to degree of urbanization. Bottom-sediment PAH assemblages are similar to those of sealcoated pavement dust regionally, implicating coal-tar-based sealcoat as a PAH source to the central and eastern lakes. Concentrations of benzo[a]pyrene in dustfrom coal-tarsealcoated pavement and adjacent soils greatly exceed generic soil screening levels, suggesting that research on human-health risk is warranted.

  1. Coal-tar-based pavement sealcoat, polycyclic aromatic Hydrocarbons (PAHs), and environmental health

    USGS Publications Warehouse

    Mahler, B.J.; Van Metre, P.C.

    2011-01-01

    Studies by the U.S. Geological Survey (USGS) have identified coal-tar-based sealcoat-the black, viscous liquid sprayed or painted on asphalt pavement such as parking lots-as a major source of polycyclic aromatic hydrocarbon (PAH) contamination in urban areas for large parts of the Nation. Several PAHs are suspected human carcinogens and are toxic to aquatic life.

  2. Biomass waste gasification - can be the two stage process suitable for tar reduction and power generation?

    PubMed

    Sulc, Jindřich; Stojdl, Jiří; Richter, Miroslav; Popelka, Jan; Svoboda, Karel; Smetana, Jiří; Vacek, Jiří; Skoblja, Siarhei; Buryan, Petr

    2012-04-01

    A pilot scale gasification unit with novel co-current, updraft arrangement in the first stage and counter-current downdraft in the second stage was developed and exploited for studying effects of two stage gasification in comparison with one stage gasification of biomass (wood pellets) on fuel gas composition and attainable gas purity. Significant producer gas parameters (gas composition, heating value, content of tar compounds, content of inorganic gas impurities) were compared for the two stage and the one stage method of the gasification arrangement with only the upward moving bed (co-current updraft). The main novel features of the gasifier conception include grate-less reactor, upward moving bed of biomass particles (e.g. pellets) by means of a screw elevator with changeable rotational speed and gradual expanding diameter of the cylindrical reactor in the part above the upper end of the screw. The gasifier concept and arrangement are considered convenient for thermal power range 100-350 kW(th). The second stage of the gasifier served mainly for tar compounds destruction/reforming by increased temperature (around 950°C) and for gasification reaction of the fuel gas with char. The second stage used additional combustion of the fuel gas by preheated secondary air for attaining higher temperature and faster gasification of the remaining char from the first stage. The measurements of gas composition and tar compound contents confirmed superiority of the two stage gasification system, drastic decrease of aromatic compounds with two and higher number of benzene rings by 1-2 orders. On the other hand the two stage gasification (with overall ER=0.71) led to substantial reduction of gas heating value (LHV=3.15 MJ/Nm(3)), elevation of gas volume and increase of nitrogen content in fuel gas. The increased temperature (>950°C) at the entrance to the char bed caused also substantial decrease of ammonia content in fuel gas. The char with higher content of ash leaving the

  3. Inhibition of HIV Replication by Cyclic and Hairpin PNAs Targeting the HIV-1 TAR RNA Loop

    PubMed Central

    Upert, Gregory; Di Giorgio, Audrey; Upadhyay, Alok; Manvar, Dinesh; Pandey, Nootan; Pandey, Virendra N.; Patino, Nadia

    2012-01-01

    Human immunodeficiency virus-1 (HIV-1) replication and gene expression entails specific interaction of the viral protein Tat with its transactivation responsive element (TAR), to form a highly stable stem-bulge-loop structure. Previously, we described triphenylphosphonium (TPP) cation-based vectors that efficiently deliver nucleotide analogs (PNAs) into the cytoplasm of cells. In particular, we showed that the TPP conjugate of a linear 16-mer PNA targeting the apical stem-loop region of TAR impedes Tat-mediated transactivation of the HIV-1 LTR in vitro and also in cell culture systems. In this communication, we conjugated TPP to cyclic and hairpin PNAs targeting the loop region of HIV-1 TAR and evaluated their antiviral efficacy in a cell culture system. We found that TPP-cyclic PNAs containing only 8 residues, showed higher antiviral potency compared to hairpin PNAs of 12 or 16 residues. We further noted that the TPP-conjugates of the 8-mer cyclic PNA as well as the 16-mer linear PNA displayed similar antiviral efficacy. However, cyclic PNAs were shown to be highly specific to their target sequences. This communication emphasizes on the importance of small constrained cyclic PNAs over both linear and hairpin structures for targeting biologically relevant RNA hairpins. PMID:23029603

  4. Which processes form the volcanic sands on Mars?

    NASA Astrophysics Data System (ADS)

    Grégoire, M.; Baratoux, D.; Mangold, N.; Arnalds, O.; Platvoet, B.; Bardinzeff, J.; Pinet, P.

    2007-12-01

    Volcanic sands are common at the surface of Mars. They are usually of basaltic composition. Occurrence of sands, mostly recognized as dark dune fields include numerous impact craters in the southern hemisphere [1], several volcanic provinces such as Cerberus and Syrtis Major[2], several impact craters in the northern hemisphere, the large basins (Hellas and Argyre), Valles Marineris, and the poles [3]. In most cases, the sands are of basaltic composition [2,4], at the exception of the polar dunes which are made of sulfates [3]. It is interesting to note that dunes have been found on the Hesperian volcanic plateau of Systis Major, while they are not reported on Tyrrhena Terra, a volcanic province similar in age and morphology to Syrtis. It seems thus that the formation of sand from volcanic material is not systematic and thus requires particular conditions. These different situations which will be presented raise the following questions. When did these volcanic sands form in the Martian history? Did they result from a long-standing and slow process operating in the present cold conditions or did they result from several episodes associated for instant to climate changes? We review several mechanisms which could account for the formation of volcanic sand on Mars from the volcanic material. In particular, we focus on the role of cold-climate processes from an analysis of terrestrial analogs in Iceland. In this case, the advance and retreat of glaciers over a recent erupted shield volcano associated with the strong catabatic winds have resulted in the rapid formation (less than few thousands years) of large volumes of sands. [1] Fenton, L. K. (2005), Potential sand sources for the dune fields in Noachis Terra, Mars, J. Geophys. Res. 110, E11004, doi :10.1029/2005JE002436. [2] Vaucher et. al, in revision for Icarus [3] Langevin et. al, (2005), Science, 307, 1584-1586 [4] Poulet F., Mangold N. and Erard S. (2003), Astron. & Astrophys. 412, L19-L23.

  5. Sand Waves in Tidal Channels

    DTIC Science & Technology

    2007-01-01

    sincerely thank Steven Borgeld, from Humboldt State University, for providing the grain size data for the Humboldt Entrance Channel. iv SAND...Wave Characteristics at Moriches Inlet... 182 APPENDIX VII – Sediment Data , Humboldt Entrance Channel, CA ........................... 186 References...waves may be limited by wave action, sand supply, and dredging activity. Bathymetric data collected at Humboldt Inlet, California, show sand waves

  6. PM 2.5 Airborne Particulates Near Frac Sand Operations.

    PubMed

    Walters, Kristin; Jacobson, Jeron; Kroening, Zachary; Pierce, Crispin

    2015-11-01

    The rapid growth of hydraulic fracturing for oil and gas extraction in the U.S. has led to 135 active "frac" sand mines, processing plants, and rail transfer stations in Wisconsin. Potential environmental health risks include increased truck traffic, noise, ecosystem loss, and groundwater, light, and air pollution. Emitted air contaminants include fine particulate matter (PM2.5) and respirable crystalline silica. Inhalation of fine dust particles causes increased mortality, cardiovascular disease, lung disease, and lung cancer. In the authors' pilot study, use of a filter-based ambient particulate monitor found PM2.5 levels of 5.82-50.8 µg/m3 in six 24-hour samples around frac sand mines and processing sites. Enforcement of the existing U.S. Environmental Protection Agency annual PM2.5 standard of 12 µg/m3 is likely to protect the public from silica exposure risks as well. PM2.5 monitoring around frac sand sites is needed to ensure regulatory compliance, inform nearby communities, and protect public health.

  7. Evaluation of sand fills.

    DOT National Transportation Integrated Search

    1973-11-01

    A popular construction technique in south Louisiana for many years has been the use of river sand to establish foundations for highways. The abundance of river sand and the need for it in excavation backfill operations across Louisiana's marshlands h...

  8. China Dust and Sand

    Atmospheric Science Data Center

    2013-04-16

    ... article title:  Dust and Sand Sweep Over Northeast China     View Larger Image ... these views of the dust and sand that swept over northeast China on March 10, 2004. Information on the height of the dust and an ...

  9. Comparisons of Unconsolidated Sediments Analyzed by APXS (MSL-Curiosity) within Gale Crater, Mars: Soils, Sands of the Barchan and Linear Dunes of the Active Bagnold Dune Field, and Ripple-field Sands.

    NASA Astrophysics Data System (ADS)

    Thompson, L. M.; O'Connell-Cooper, C.; Spray, J. G.; Gellert, R.; Boyd, N. I.; Desouza, E.

    2017-12-01

    The MSL-APXS has analyzed a variety of unconsolidated sediments within the Gale impact crater, including soils, sands from barchan [High, Namib dunes], and linear dunes [Nathan Bridges, Mount Desert dunes], within the active Bagnold dune field, and sands from two smaller ripple fields ("mega-ripples"). The Gale "soils" (unsorted, unconsolidated sediments, ranging from fine-grained particles (including dust) to coarser "pebbly" material [>2 mm]), are, to a large degree, similar to Martian basaltic soils quantified by APXS, at Gusev crater (MER-A_Spirit) and Meridiani Planum (MER-B_Opportunity). Some local contributions are indicated by, for example, the enriched K levels (relative to a martian average basaltic soil [ABS]) within coarser Gale soil samples, and a Cr, Mn, Fe enrichment within finer-grained samples. Sands (grain size 62 µm to 2 mm) of the Bagnold dunes, generally, exhibit elevated Mg and Ni, indicating enrichment from olivine and pyroxene, but depleted S, Cl and Zn, indicating high activity levels and low dust. Compositional differences, related both to position within a dune (i.e., crest versus off-crest sand), and type of dune (linear versus barchan), are identified. Off-crest sands have Na, Al, Si, K, P contents similar to (or slightly depleted, relative to) the ABS, enrichment in Mg, and low dust content, whilst crest sands contain very high Mg and Ni (relative to the ABS), low felsic elemental concentrations and very low dust content. Cr is significantly enriched (and, to a lesser degree, Mn, Fe, Ti) in the off-crest sands of the linear dunes. In contrast, barchan dunes off-crest sands have Cr, Mn, Fe, and Ti abundances similar to those in the Gale soils. Additionally, Ni concentrations in barchan dunes off-crest sands are enriched relative to the linear dunes. Analyses from a small, isolated "mega-ripple" reveal a composition similar to that of the Gale soils, including a high dust content. The second mega-ripple, within a larger ripple field, is

  10. 43 CFR 3141.6-5 - Fair market value for combined hydrocarbon leases.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Fair market value for combined hydrocarbon leases. 3141.6-5 Section 3141.6-5 Public Lands: Interior Regulations Relating to Public Lands (Continued... SAND AREAS Leasing in Special Tar Sand Areas § 3141.6-5 Fair market value for combined hydrocarbon...

  11. Simulation of groundwater flow in the "1,500-foot" sand and "2,000-foot" sand, with scenarios to mitigate saltwater migration in the "2,000-foot" sand of the Baton Rouge area, Louisiana

    USGS Publications Warehouse

    Heywood, Charles E.; Griffith, Jason M.; Lovelace, John K.

    2014-01-01

    Groundwater withdrawals have caused saltwater to encroach into freshwater-bearing aquifers beneath Baton Rouge, Louisiana. Groundwater investigations in the 1960s identified a freshwater-saltwater interface located at the Baton Rouge Fault, across which abrupt changes in water levels occur. Aquifers south of the fault generally contain saltwater, and aquifers north of the fault contain freshwater, though limited saltwater encroachment has been detected within 7 of the 10 aquifers north of the fault. The 10 aquifers beneath the Baton Rouge area, which includes East and West Baton Rouge Parishes, Pointe Coupee Parish, and East and West Feliciana Parishes, provided about 167 million gallons per day (Mgal/d) for public supply and industrial use in 2010. Groundwater withdrawals from the “2,000-foot” sand in East Baton Rouge Parish have caused water-level drawdown as great as 356 feet (ft) and induced saltwater movement northward across the fault. Saltwater encroachment threatens industrial wells that are located about 3 miles north of the fault. Constant and variable-density groundwater models were developed with the MODFLOW and SEAWAT groundwater modeling codes to evaluate strategies to control saltwater migration, including changes in the distribution of groundwater withdrawals and installation of “scavenger” wells to intercept saltwater before it reaches existing production wells. Six hypothetical scenarios simulated the effects of different groundwater withdrawal options on groundwater levels within the “1,500-foot” sand and the “2,000-foot” sand and the transport of saltwater within the “2,000-foot” sand during 2008–47. Scenario 1 is considered a base case for comparison to the other five scenarios and simulates continuation of 2007 reported groundwater withdrawals. Scenario 2 simulates discontinuation of withdrawals from seven selected industrial wells located in the northwest corner of East Baton Rouge Parish and predicts that water levels

  12. Early Childhood: Discovery through Sand Play.

    ERIC Educational Resources Information Center

    McIntyre, Margaret

    1982-01-01

    Suggestions are given for using sand play to teach science related vocabulary and concepts to preschool and primary age children by using dry sand, wet sand, different sizes and shapes of spoons and containers, sieves, and funnels. (DC)

  13. Connecting onshore and offshore near-surface geology: Delaware's sand inventory project

    USGS Publications Warehouse

    Ramsey, K.W.; Jordan, R.R.; Talley, J.H.

    1999-01-01

    Beginning in 1988, the Delaware Geological Survey began a program to inventory on-land sand resources suitable for beach nourishment. The inventory included an assessment of the native beach textures using existing data and developing parameters of what would be considered suitable sand textures for Delaware's Atlantic beaches. An assessment of the economics of on-land sand resources was also conducted, and it was determined that the cost of the sand was competitive with offshore dredging costs. In addition, the sand resources were put into a geologic context for purposes of predicting which depositional environments and lithostratigraphic units were most likely to produce suitable sand resources. The results of the work identified several suitable on-land sand resource areas in the Omar and Beaverdam formations that were deposited in barrier-tidal delta and fluvial-estuarine environments, respectively. The identified on-land resources areas have not been utilized due to difficulties of truck transport and development pressures in the resource areas. The Delaware Geological Survey's participation in years 8, 9, and 10 of the Continental Margins Program was developed to extend the known resource areas onshore to offshore Delaware in order to determine potential offshore sand resources for beach nourishment. Years 8 and 9 involved primarily the collection of all available data on the offshore geology. These data included all seismic lines, surface grab samples, and cores. The data were filtered for those that had reliable locations and geologic information that could be used for geologic investigations. Year 10 completed the investigations onshore by construction of a geologic cross-section from data along the coast of Delaware from Cape Henlopen to Fenwick. This cross section identified the geologic units and potential sand resource bodies as found immediately along the coast. These units and resources are currently being extended offshore and tied to known and

  14. Asbestos in play sand

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Langer, A.M.; Nolan, R.P.

    1987-04-02

    A letter in the New England Journal of Medicine (Oct. 2 issue) stated that a carbonate sand marketed in New Jersey was contaminated with 2 to 4 percent tremolite asbestos. The authors were called on by one of the federal agencies to repeat the analysis of this sand, specifically for its asbestos content. The sand was pulverized and immersed in oils with known refractive indexes, and the predominant amphibole was characterized by polarized light microscopy. The optical characteristics were noted, and the indexes of refraction were measured and found to be consistent with tremolite. On the basis of optical characterization,more » the authors concluded that all the tremolite visualized with light microscopy consisted of large, single cleavage fragments and was not asbestiform. They used the technique of x-ray diffraction, as did the author of the original report, which showed the presence of an amphibole mineral (probably tremolite) in the carbonate sand. The technique was not used, and cannot be used, to distinguish between the tremolite habits (asbestiform or nonasbestiform). An acid-insoluble residue, recovered from the carbonate sand, was examined by analytic electron microscopy. The tremolite grains were observed to consist of single untwinned, crystalline fragments. Few defects were noted. Selected area electron diffraction nets were indicative of fragments lying near or at the common amphibole cleavage plane. These characteristics are consistent with cleavage fragments and not asbestos. Aspect ratios reflected short particles (less than 5.1). On the basis of their examination of the carbonate play sand, they conclude that it did not contain tremolite asbestos.« less

  15. Comparison of buried sand ridges and regressive sand ridges on the outer shelf of the East China Sea

    NASA Astrophysics Data System (ADS)

    Wu, Ziyin; Jin, Xianglong; Zhou, Jieqiong; Zhao, Dineng; Shang, Jihong; Li, Shoujun; Cao, Zhenyi; Liang, Yuyang

    2017-06-01

    Based on multi-beam echo soundings and high-resolution single-channel seismic profiles, linear sand ridges in U14 and U2 on the East China Sea (ECS) shelf are identified and compared in detail. Linear sand ridges in U14 are buried sand ridges, which are 90 m below the seafloor. It is presumed that these buried sand ridges belong to the transgressive systems tract (TST) formed 320-200 ka ago and that their top interface is the maximal flooding surface (MFS). Linear sand ridges in U2 are regressive sand ridges. It is presumed that these buried sand ridges belong to the TST of the last glacial maximum (LGM) and that their top interface is the MFS of the LGM. Four sub-stage sand ridges of U2 are discerned from the high-resolution single-channel seismic profile and four strikes of regressive sand ridges are distinguished from the submarine topographic map based on the multi-beam echo soundings. These multi-stage and multi-strike linear sand ridges are the response of, and evidence for, the evolution of submarine topography with respect to sea-level fluctuations since the LGM. Although the difference in the age of formation between U14 and U2 is 200 ka and their sequences are 90 m apart, the general strikes of the sand ridges are similar. This indicates that the basic configuration of tidal waves on the ECS shelf has been stable for the last 200 ka. A basic evolutionary model of the strata of the ECS shelf is proposed, in which sea-level change is the controlling factor. During the sea-level change of about 100 ka, five to six strata are developed and the sand ridges develop in the TST. A similar story of the evolution of paleo-topography on the ECS shelf has been repeated during the last 300 ka.

  16. The use of Papuan iron sand and river sand for fine aggregate in mortar for nuclear radiation shield application

    NASA Astrophysics Data System (ADS)

    Dahlan, K.; Haryati, E.; Aninam, Y. S.

    2018-03-01

    This study explores the effect of fine aggregate on mortar properties and its application as a nuclear shield. This study was based on a hypothesis that the types of aggregate applied as radiation shield determined the level of its effectiveness on preventing nuclear radiation. There are two types and sources of fine aggregate that was used as main ingredients for mortar production in this research, namely iron sand and river sand. Both types of sand were derived from the respective regions of Sarmi and Jayapura, Papua. The results showed that the mortar materials that were produced with the iron sand provided better results in dispelling radiation than that of river sand. The compressive strength of fine aggregate from the iron sand was 21.62 MPa, while the compressive strength of the river sand was 16.8 MPa. Measuring the attenuation coefficient of material, we found that the largest aggregated value of mortar with fine iron sand reached 0.0863 / cm. On the other hand, the smallest HVT (Half Value Thickness) was obtained from the iron sand mortar, at 8.03 cm.

  17. Constitutive Soil Properties for Mason Sand and Kennedy Space Center

    NASA Technical Reports Server (NTRS)

    Thomas, Michael A.; Chitty, Daniel E.

    2011-01-01

    Accurate soil models are required for numerical simulations of land landings for the Orion Crew Exploration Vehicle (CEV). This report provides constitutive material models for two soil conditions at Kennedy Space Center (KSC) and four conditions of Mason Sand. The Mason Sand is the test sand for LaRC s drop tests and swing tests of the Orion. The soil models are based on mechanical and compressive behavior observed during geotechnical laboratory testing of remolded soil samples. The test specimens were reconstituted to measured in situ density and moisture content. Tests included: triaxial compression, hydrostatic compression, and uniaxial strain. A fit to the triaxial test results defines the strength envelope. Hydrostatic and uniaxial tests define the compressibility. The constitutive properties are presented in the format of LSDYNA Material Model 5: Soil and Foam. However, the laboratory test data provided can be used to construct other material models. The soil models are intended to be specific to the soil conditions they were tested at. The two KSC models represent two conditions at KSC: low density dry sand and high density in-situ moisture sand. The Mason Sand model was tested at four conditions which encompass measured conditions at LaRC s drop test site.

  18. Lack of effect of menthol level and type on smokers' estimated mouth level exposures to tar and nicotine and perceived sensory characteristics of cigarette smoke.

    PubMed

    Ashley, Madeleine; Dixon, Mike; Sisodiya, Ajit; Prasad, Krishna

    2012-08-01

    Menthol can reduce sensory irritation and it has been hypothesised that this could result in smokers of mentholated cigarettes taking larger puffs and deeper post-puff inhalations thereby obtaining higher exposures to smoke constituents than smokers of non-mentholated cigarettes. The aim of our study was to use part-filter analysis methodology to assess the effects of cigarette menthol loading on regular and occasional smokers of mentholated cigarettes. We measured mouth level exposure to tar and nicotine and investigated the effects of mentholation on smokers' sensory perceptions such as cooling and irritation. Test cigarettes were produced containing no menthol and different loadings of synthetic and natural l-menthol at 1 and 4mg ISO tar yields. A target of 100 smokers of menthol cigarettes and 100 smokers who predominantly smoked non-menthol cigarettes from both 1 and 4mg ISO tar yield categories were recruited in Poland and Japan. Each subject was required to smoke the test cigarette types of their usual ISO tar yield. There were positive relationships between menthol loading and the perceived 'strength of menthol taste' and 'cooling' effect. However, we did not see marked menthol-induced reductions in perceived irritation or menthol-induced increases in mouth level exposure to tar and nicotine. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Land and water impacts of oil sands production in Alberta.

    PubMed

    Jordaan, Sarah M

    2012-04-03

    Expansion of oil sands development results not only in the release of greenhouse gas emissions, but also impacts land and water resources. Though less discussed internationally due to to their inherently local nature, land and water impacts can be severe. Research in key areas is needed to manage oil sands operations effectively; including improved monitoring of ground and surface water quality. The resulting information gap means that such impacts are not well understood. Improved analyses of oil sands products are required that compare land and water use with other transportation fuel pathways and use a regional perspective so local effects can be considered and mitigated.

  20. Sand-wave movement on Little Georges Bank

    USGS Publications Warehouse

    Twichell, David C.

    1983-01-01

    A 1-x-1.5-km area on Little Georges Bank (centered at 41?08?N., 68?04?W.) was mapped three times during a ten-month period by sidescan sonar and echo-sounding techniques to assess the morphology and mobility of sand waves on Georges Bank. Sand-wave amplitudes in the survey area ranged from 1-11 m although most were 5-7 m. Wavelengths were not constant as the crests were sinuous and in places, even bifurcated. The sand waves are asymmetrical with their steepest sides facing northwest; however, gradients of their steep sides mostly are 4?-10? which is well below the angle of repose for sand in water. Sand waves tended to have greater relief and a sharper asymmetry during the survey in September than during those in June or April. During the survey period the sand waves moved but the direction and rate of motion was variable. Even along an individual sand wave some parts moved as much as 60 m between surveys while other parts apparently remained stationary. The sand waves were asymmetrical, but movement was not consistently in the direction that the steep sides faced. Along the same sand wave, parts moved to the northwest while other parts moved to the southeast. Despite the complex pattern of sand motion, the mean displacement of the sand waves was below the resolution of the survey technique; to resolve it, a longer survey is needed.

  1. 43 CFR 3140.0-5 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... for the removal of gas and nongaseous hydrocarbon substances other than coal, oil shale or gilsonite... Existing Oil and Gas Leases and Valid Claims Based on Mineral Locations § 3140.0-5 Definitions. As used in... Sand Areas, as containing substantial deposits of tar sand. (d) Owner of an oil and gas lease means all...

  2. 43 CFR 3140.0-5 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... for the removal of gas and nongaseous hydrocarbon substances other than coal, oil shale or gilsonite... Existing Oil and Gas Leases and Valid Claims Based on Mineral Locations § 3140.0-5 Definitions. As used in... Sand Areas, as containing substantial deposits of tar sand. (d) Owner of an oil and gas lease means all...

  3. 43 CFR 3140.0-5 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... for the removal of gas and nongaseous hydrocarbon substances other than coal, oil shale or gilsonite... Existing Oil and Gas Leases and Valid Claims Based on Mineral Locations § 3140.0-5 Definitions. As used in... Sand Areas, as containing substantial deposits of tar sand. (d) Owner of an oil and gas lease means all...

  4. 43 CFR 3140.0-5 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... for the removal of gas and nongaseous hydrocarbon substances other than coal, oil shale or gilsonite... Existing Oil and Gas Leases and Valid Claims Based on Mineral Locations § 3140.0-5 Definitions. As used in... Sand Areas, as containing substantial deposits of tar sand. (d) Owner of an oil and gas lease means all...

  5. METHOD OF PROCESSING MONAZITE SAND

    DOEpatents

    Calkins, G.D.

    1957-10-29

    A method is given for the pretreatment of monazite sand with sodium hydroxide. When momazite sand is reacted with sodium hydroxide, the thorium, uranium, and rare earths are converted to water-insoluble hydrous oxides; but in the case of uranium, the precipitate compound may at least partly consist of a slightly soluble uranate. According to the patent, monazite sand is treated with an excess of aqueous sodium hydroxide solution, and the insoluble compounds of thorium, uranium, and the rare earths are separated from the aqueous solution. This solution is then concentrated causing sodium phosphate to crystallize out. The crystals are removed from the remaining solution, and the solution is recycled for reaction with a mew supply of momazite sand.

  6. Implications of Use of Coal-Tar-Based Pavement Sealcoat on Urban Water Quality

    NASA Astrophysics Data System (ADS)

    Van Metre, P. C.

    2015-12-01

    Coal-tar-based (CT) sealcoat is used to protect and improve the appearance of asphalt pavement of driveways and parking lots primarily in the central and eastern U.S. and in Canada. CT sealcoat typically is 20 to 35% crude coal tar or coal-tar pitch and contains from 50,000 to 100,000 mg/kg polycyclic aromatic hydrocarbons (PAH), about 1,000 times more than asphalt-based (AS) sealcoat or asphalt itself. Tires and snowplows abrade the friable sealcoat surface into fine particles—median total PAH concentrations in dust from CT-sealcoated pavement are 2,200 mg/kg compared to a median concentration of 11 mg/kg for dust from unsealed pavement. Use of CT sealcoat has several implications for urban streams and lakes. Source apportionment modeling has indicated that, in regions where CT sealcoat is prevalent, particles from sealcoated pavement are contributing the majority of the PAHs to recently deposited lake sediment, often resulting in sediment concentrations above toxicity thresholds based on effects-based sediment quality guidelines. Acute 2-day laboratory toxicity testing of simulated runoff from CT-sealcoated pavement to a cladoceran (Ceriodaphnia dubia) and fathead minnows (Pimephales promelas) demonstrated that toxicity continues for samples collected for weeks or months following sealcoat application and that toxicity is enhanced by exposure to UV light. Using the fish-liver cell line RTL-W1, runoff collected as much as 36 days following CT-sealcoat application has been demonstrated to cause DNA damage and impair DNA repair capacity. These results demonstrate that CT runoff is a potential hazard to aquatic ecosystems and that exposure to sunlight can enhance toxicity and genetic damage. Recent research has provided direct evidence that restricting use of CT sealcoat in a watershed can lead to a substantial reduction in PAH concentrations in receiving water bodies.

  7. Tar yields from low-temperature carbonization of coal facies from the Powder River Basin, Wyoming, USA

    USGS Publications Warehouse

    Stanton, Ronald W.; Warwick, Peter D.; Swanson, Sharon M.

    2005-01-01

    Tar yields from low-temperature carbonization correlate with the amount of crypto-eugelinite in samples selected to represent petrographically distinct coal facies of the Wyodak-Anderson coal zone. Tar yields from Fischer Assay range from <1 to 11 wt.% on a dry basis and correspond (r = 0.72) to crypto-eugelinite contents of the coal that range from 15 to 60 vol.%. Core and highwall samples were obtained from active surface mines in the Gillette field, Powder River Basin, Wyoming. Because the rank of the samples is essentially the same, differences in low-temperature carbonization yields are interpreted from compositional differences, particularly the crypto-eugelinite content. In the Wyodak-Anderson coal zone, crypto-eugelinite probably was derived from degraded humic matter which absorbed decomposition products from algae, fungi, bacteria, and liptinitic plant parts (materials possibly high in hydrogen). Previous modeling of the distribution of crypto-eugelinite in the discontinuous Wyodak-Anderson coal zone indicated that tar yields should be greater from coal composing the upper part and interior areas than from coal composing the lower parts and margins of the individual coal bodies. It is possible that hydrocarbon yields from natural coalification processes would be similar to yields obtained from laboratory pyrolysis. If so, the amount of crypto-eugelinite may also be an important characteristic when evaluating coal as source rock for migrated hydrocarbons.

  8. Effect of Transport and Aging Processes on Metal Speciation in Iron Oxyhydroxide Aggregates, Tar Creek Superfund Site, Oklahoma

    NASA Astrophysics Data System (ADS)

    Estes, E. R.; Schaider, L. A.; Shine, J. P.; Brabander, D. J.

    2010-12-01

    Following the cessation of mining activity in the late 20th century, Tar Creek Superfund Site was left highly contaminated by Pb, Zn, and Cd. Tar Creek, which flows through the site and into the Neosho River, has been studied extensively because of its potential to transport metals from the mining site to downstream communities. Previous research identified aggregated iron oxyhydroxide material, which forms when mine seepage mixes with Tar Creek surface water, as a major transport vector of metals. Frequent flooding in Tar Creek deposits aggregates on downstream floodplains, where wetting and drying processes alter the speciation of iron and other metals. This study seeks to better quantify those changes and to determine how transport and aging affects the human and ecological health risk. Sequential extractions of aggregate samples collected from the creek demonstrate that Fe is present in both amorphous (10-35% of Fe extracted) and more crystalline (8-23% of Fe extracted) phases. Substantial portions of heavy metals sorb to amorphous iron oxyhydroxide phases (accounting for 10-30% of Pb and Zn extracted) but are not associated with more crystalline iron oxide phases (representing only 1% or less of the Pb and Zn extracted). Samples have a high organic matter content (18-25% mass loss on ignition), but only Fe was significantly extracted by the oxidizing step targeting organic matter (1-2% of Pb and Zn extracted, but 10-26% of Fe extracted). The majority of metals were extracted by the soluble or residual steps. If metals and organic matter inhibit transformation of amorphous iron oxyhydroxide material to nano and crystalline iron oxides, then a steady-state volume of amorphous iron oxyhydroxide material with a high total sorption capacity may exist within Tar Creek, enhancing the metal flux accommodated by this transport mechanism. Once transported downstream and deposited on floodplains, however, it is hypothesized that repeated changes in soil matrix

  9. The chimeric VirA-tar receptor protein is locked into a highly responsive state.

    PubMed Central

    Turk, S C; van Lange, R P; Sonneveld, E; Hooykaas, P J

    1993-01-01

    The wild-type VirA protein is known to be responsive not only to phenolic compounds but also to sugars via the ChvE protein (G. A. Cangelosi, R. G. Ankenbauer, and E. W. Nester, Proc. Natl. Acad. Sci. USA 87:6708-6712, 1990, and N. Shimoda, A. Toyoda-Yamamoto, J. Nagamine, S. Usami, M. Katayama, Y. Sakagami, and Y. Machida, Proc. Natl. Acad. Sci. USA 87:6684-6688, 1990). It is shown here that the mutant VirA(Ser-44, Arg-45) protein and the chimeric VirA-Tar protein are no longer responsive to sugars and the ChvE protein. However, whereas the chimeric VirA-Tar protein was found to be locked in a highly responsive state, the VirA(Ser-44, Arg-45) mutant protein appeared to be locked in a low responsive state. This difference turned out to be important for tumorigenicity of the host strains in virulence assays on Kalanchoë daigremontiana. Images PMID:8366057

  10. Satellite Monitoring Over the Canadian Oil Sands: Highlights from Aura OMI and TES

    NASA Technical Reports Server (NTRS)

    Shephard, Mark W.; McLinden, Chris; Fioletov, Vitali; Cady-Pereira, Karen E.; Krotkov, Nick A.; Boersma, Folkert; Li, Can; Luo, Ming; Bhartia, P. K.; Joiner, Joanna

    2014-01-01

    Satellite remote sensing provides a unique perspective for air quality monitoring in and around the Canadian Oil Sands as a result of its spatial and temporal coverage. Presented are Aura satellite observations of key pollutants including nitrogen dioxide (NO2), sulfur dioxide (SO2), carbon monoxide (CO), ammonia (NH3), methanol (CH3OH), and formic acid (HCOOH) over the Canadian Oil Sands. Some of the highlights include: (i) the evolution of NO2 and SO2 from the Ozone Monitoring Instrument (OMI), including comparisons with other nearby sources, (ii) two years of ammonia, carbon monoxide, methanol, and formic acid observations from 240 km North-South Tropospheric Emission Spectrometer (TES) transects through the oils sands, and (iii) preliminary insights into emissions derived from these observations.

  11. Do increases in cigarette prices lead to increases in sales of cigarettes with high tar and nicotine yields?

    PubMed

    Farrelly, Matthew C; Loomis, Brett R; Mann, Nathan H

    2007-10-01

    We used scanner data on cigarette prices and sales collected from supermarkets across the United States from 1994 to 2004 to test the hypothesis that cigarette prices are positively correlated with sales of cigarettes with higher tar and nicotine content. During this period the average inflation-adjusted price for menthol cigarettes increased 55.8%. Price elasticities from multivariate regression models suggest that this price increase led to an increase of 1.73% in sales-weighted average tar yields and a 1.28% increase in sales-weighted average nicotine yields for menthol cigarettes. The 50.5% price increase of nonmenthol varieties over the same period yielded an estimated increase of 1% in tar per cigarette but no statistically significant increase in nicotine yields. An ordered probit model of the impact of cigarette prices on cigarette strength (ultra-light, light, full flavor, unfiltered) offers an explanation: As cigarette prices increase, the probability that stronger cigarette types will be sold increases. This effect is larger for menthol than for nonmenthol cigarettes. Our results are consistent with earlier population-based cross-sectional and longitudinal studies showing that higher cigarette prices and taxes are associated with increasing consumption of higher-yield cigarettes by smokers.

  12. Numerical simulation of wind-sand movement in the reversed flow region of a sand dune with a bridge built downstream.

    PubMed

    He, Wei; Huang, Ning; Xu, Bin; Wang, Wenbo

    2018-04-23

    A bridge built inside the reversed flow region of a sand dune will change the characteristics of wind-sand movement in this region. The Reynolds-averaged Navier-Stokes simulation and discrete particle tracing are used to simulate the wind-sand movement around a sand dune with a bridge built inside the reversed region. Three cases with different bridge positions are studied. The results show that 1) compared with the isolated dune case, a tall bridge built at the leeward toe leads to an increase in the deposition rate on the leeward slope and a longer reversed flow region downstream of the sand dune; meanwhile, the high speed of crosswind on the bridge indicates that some measures should be taken to protect trains from strong crosswind; 2) a low bridge at the leeward toe has little effect on the sand deposition and reversed flow region of the dune; however, low sand transport rate and crosswind speed on the bridge show that anti-crosswind/sand measures should be taken according to the actual situation and 3) a low bridge on the leeward slope has little effect on the length of reversed flow region, however, high crosswind speed and sand flux on the bridge reveal the need of anti-crosswind/sand measures on the bridge. Moreover, the bridges in the reversed flow region increase the sand flux near the leeward crest; as a result, the moving patterns of the sand dune are changed.

  13. Fungal alteration of organic coatings on sand grains

    NASA Astrophysics Data System (ADS)

    Rothhardt, S.; Gleixner, G.; Benzerara, K.; Fischer, C.; Gaupp, R.

    2012-04-01

    We studied the fungal alteration of organically coated sand particles, sampled in Eocene sediments in the open cast mining Profen, near Leipzig (Germany). These organic coatings were formed on sand grains after their sedimentation owing to mobilization of organic matter from younger coal layers. The organic coatings formed non-continuous layers on quartz grains, measuring few micrometers up to 30 µm in thickness. It has been shown that organic coatings on sand grains retain efficiently dissolved metals by adsorption from groundwaters. They consequently might be used as adsorbent to purify low heavy metal contaminated water. However, their stability has not been assessed yet especially in the oxic environment and, more specifically, in the presence of microorganisms. This is important in order to evaluate whether coated sands could act as a reliable tool in remediation. In order to address this question we characterized the fungal alteration of organic coatings on sand grains using several techniques, including scanning electron microscopy (SEM), scanning transmission X-ray microscopy (STXM) and vertical scanning interferometry (VSI). Sand grains coated with organics were incubated on complex yeast medium with and without Schizophyllum commune to estimate changes in heavy metal retention. Formation of biominerals and etch pits is induced by fungal colonization as shown by SEM. Surface topography analysis was performed using VSI technique. Etch pit depth ranges from 0.5 to 1 µm. Pit formation is limited to the organic coating; dissolution of quartz grains was not detected. Using STXM we measured near-edge X-ray absorption fine structure (NEXAFS) spectra at the C K-edge, N-edge, and O K-edge to characterize the different organic compartments (fungi, genuine organic coatings, altered organic coatings) down to the 25-nm scale. We observed in the spectra measured at the C K-edge on the altered organic coatings a decrease in aromatic and phenolic groups as well as an

  14. Identifying the source of tar balls deposited along the beaches of Goa in 2013 and comparing with historical data collected along the West Coast of India.

    PubMed

    Suneel, V; Vethamony, P; Naik, B G; Krishna, M S; Jadhav, Lakshmikant

    2015-09-15

    Deposition of oil residues, also known as tar balls, is a seasonal phenomenon, and it occurs only in the southwest monsoon season along the west coast of India. This has become a serious environmental issue, as Goa is a global tourist destination. The present work aims at identifying the source oil of the tar balls that consistently depositing along the Goa coast using multi-marker fingerprint technique. In this context, the tar ball samples collected in May 2013 from 9 beaches of Goa coast and crude oils from different oil fields and grounded ship were subject to multi-marker analyses such as n-alkanes, pentacyclic terpanes, regular steranes, compound specific isotope analysis (CSIA) and principle component analysis (PCA). The n-alkane weathering index shows that samples have been weathered to various degrees, and the status of weathering is moderate. Since the international tanker route passes closer to the west coast of India (WCI), it is generally presumed that tanker wash is the source of the tar balls. We found that 2010/2011 tar balls are as tanker wash, but the present study demonstrates that the Bombay High (BH) oil fields can also contribute to oil contamination (tar balls) along ≈ 650 km stretch of the WCI, running from Gujarat in the north to Goa in the south. The simulated trajectories show that all the particles released in April traveled in the southeast direction, and by May, they reached the Goa coast with the influence of circulation of Indian monsoon system. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Thermodynamic studies of a series of homologous HIV-1 TAR RNA ligands reveal that loose binders are stronger Tat competitors than tight ones.

    PubMed

    Pascale, Lise; Azoulay, Stéphane; Di Giorgio, Audrey; Zenacker, Laura; Gaysinski, Marc; Clayette, Pascal; Patino, Nadia

    2013-06-01

    RNA is a major drug target, but the design of small molecules that modulate RNA function remains a great challenge. In this context, a series of structurally homologous 'polyamide amino acids' (PAA) was studied as HIV-1 trans-activating response (TAR) RNA ligands. An extensive thermodynamic study revealed the occurence of an enthalpy-entropy compensation phenomenon resulting in very close TAR affinities for all PAA. However, their binding modes and their ability to compete with the Tat fragment strongly differ according to their structure. Surprisingly, PAA that form loose complexes with TAR were shown to be stronger Tat competitors than those forming tight ones, and thermal denaturation studies demonstrated that loose complexes are more stable than tight ones. This could be correlated to the fact that loose and tight ligands induce distinct RNA conformational changes as revealed by circular dichroism experiments, although nuclear magnetic resonance (NMR) experiments showed that the TAR binding site is the same in all cases. Finally, some loose PAA also display promising inhibitory activities on HIV-infected cells. Altogether, these results lead to a better understanding of RNA interaction modes that could be very useful for devising new ligands of relevant RNA targets.

  16. 21 CFR 740.18 - Coal tar hair dyes posing a risk of cancer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Coal tar hair dyes posing a risk of cancer. 740.18... posing a risk of cancer. (a) The principal display panel of the label and any labeling accompanying a... your skin and has been determined to cause cancer in laboratory animals. (b) Hair dyes containing any...

  17. 21 CFR 740.18 - Coal tar hair dyes posing a risk of cancer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 7 2011-04-01 2010-04-01 true Coal tar hair dyes posing a risk of cancer. 740.18... posing a risk of cancer. (a) The principal display panel of the label and any labeling accompanying a... your skin and has been determined to cause cancer in laboratory animals. (b) Hair dyes containing any...

  18. 21 CFR 740.18 - Coal tar hair dyes posing a risk of cancer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 7 2014-04-01 2014-04-01 false Coal tar hair dyes posing a risk of cancer. 740.18... posing a risk of cancer. (a) The principal display panel of the label and any labeling accompanying a... your skin and has been determined to cause cancer in laboratory animals. (b) Hair dyes containing any...

  19. 21 CFR 740.18 - Coal tar hair dyes posing a risk of cancer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 7 2013-04-01 2013-04-01 false Coal tar hair dyes posing a risk of cancer. 740.18... posing a risk of cancer. (a) The principal display panel of the label and any labeling accompanying a... your skin and has been determined to cause cancer in laboratory animals. (b) Hair dyes containing any...

  20. Critical state of sand matrix soils.

    PubMed

    Marto, Aminaton; Tan, Choy Soon; Makhtar, Ahmad Mahir; Kung Leong, Tiong

    2014-01-01

    The Critical State Soil Mechanic (CSSM) is a globally recognised framework while the critical states for sand and clay are both well established. Nevertheless, the development of the critical state of sand matrix soils is lacking. This paper discusses the development of critical state lines and corresponding critical state parameters for the investigated material, sand matrix soils using sand-kaolin mixtures. The output of this paper can be used as an interpretation framework for the research on liquefaction susceptibility of sand matrix soils in the future. The strain controlled triaxial test apparatus was used to provide the monotonic loading onto the reconstituted soil specimens. All tested soils were subjected to isotropic consolidation and sheared under undrained condition until critical state was ascertain. Based on the results of 32 test specimens, the critical state lines for eight different sand matrix soils were developed together with the corresponding values of critical state parameters, M, λ, and Γ. The range of the value of M, λ, and Γ is 0.803-0.998, 0.144-0.248, and 1.727-2.279, respectively. These values are comparable to the critical state parameters of river sand and kaolin clay. However, the relationship between fines percentages and these critical state parameters is too scattered to be correlated.

  1. Formation and evolution of Tar Balls from Northwestern US wildfires

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sedlacek III, Arthur J.; Buseck, Peter R.; Adachi, Kouji

    Biomass burning is a major source of light-absorbing black and brown carbonaceous particles. Brown carbon is a poorly characterized mixture that includes tar balls (TBs), a type of carbonaceous particle apparently unique to biomass burning. Here we describe the first atmospheric observations of the formation and evolution of TBs from forest fires. Aerosol particles were collected on TEM grids during aircraft transects at various downwind distances from the Colockum Tarp wildland fire. TB mass fractions, derived from TEM and in-situ measurements, increased from < 1 % near the fire to 31–45 % downwind, with little change in TB diameter. Single-scatteringmore » albedo determined from scattering and absorption measurements increased slightly with downwind distance. Similar TEM and SSA results were observed sampling multiple wildfires. Mie calculations are consistent with weak light absorbance by TBs (m = 1.56–0.02i) but not consistent with order-of-magnitude stronger absorption observed in different settings. The field-derived TB mass fractions reported here indicate that this particle type should be accounted for in biomass-burn emission inventories.« less

  2. Formation and evolution of Tar Balls from Northwestern US wildfires

    DOE PAGES

    Sedlacek III, Arthur J.; Buseck, Peter R.; Adachi, Kouji; ...

    2018-01-30

    Biomass burning is a major source of light-absorbing black and brown carbonaceous particles. Brown carbon is a poorly characterized mixture that includes tar balls (TBs), a type of carbonaceous particle apparently unique to biomass burning. Here we describe the first atmospheric observations of the formation and evolution of TBs from forest fires. Aerosol particles were collected on TEM grids during aircraft transects at various downwind distances from the Colockum Tarp wildland fire. TB mass fractions, derived from TEM and in-situ measurements, increased from < 1 % near the fire to 31–45 % downwind, with little change in TB diameter. Single-scatteringmore » albedo determined from scattering and absorption measurements increased slightly with downwind distance. Similar TEM and SSA results were observed sampling multiple wildfires. Mie calculations are consistent with weak light absorbance by TBs (m = 1.56–0.02i) but not consistent with order-of-magnitude stronger absorption observed in different settings. The field-derived TB mass fractions reported here indicate that this particle type should be accounted for in biomass-burn emission inventories.« less

  3. Field observations of artificial sand and oil agglomerates

    USGS Publications Warehouse

    Dalyander, Patricia (Soupy); Long, Joseph W.; Plant, Nathaniel G.; McLaughlin, Molly R.; Mickey, Rangley C.

    2015-01-01

    Oil that comes into the surf zone following spills, such as occurred during the 2010 Deepwater Horizon (DWH) blowout, can mix with local sediment to form heavier-than-water sand and oil agglomerates (SOAs), at times in the form of mats a few centimeters thick and tens of meters long. Smaller agglomerates that form in situ or pieces that break off of larger mats, sometimes referred to as surface residual balls (SRBs), range in size from sand-sized grains to patty-shaped pieces several centimeters (cm) in diameter. These mobile SOAs can cause beach oiling for extended periods following the spill, on the scale of years as in the case of DWH. Limited research, including a prior effort by the U.S. Geological Survey (USGS) investigating SOA mobility, alongshore transport, and seafloor interaction using numerical model output, focused on the physical dynamics of SOAs. To address this data gap, we constructed artificial sand and oil agglomerates (aSOAs) with sand and paraffin wax to mimic the size and density of genuine SOAs. These aSOAs were deployed in the nearshore off the coast of St. Petersburg, Florida, during a field experiment to investigate their movement and seafloor interaction. This report presents the methodology for constructing aSOAs and describes the field experiment. Data acquired during the field campaign, including videos and images of aSOA movement in the nearshore (1.5-meter and 0.5-meter water depth) and in the swash zone, are also presented in this report.

  4. Class III Mid-Term Project, "Increasing Heavy Oil Reserves in the Wilmington Oil Field Through Advanced Reservoir Characterization and Thermal Production Technologies"

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Scott Hara

    2007-03-31

    The overall objective of this project was to increase heavy oil reserves in slope and basin clastic (SBC) reservoirs through the application of advanced reservoir characterization and thermal production technologies. The project involved improving thermal recovery techniques in the Tar Zone of Fault Blocks II-A and V (Tar II-A and Tar V) of the Wilmington Field in Los Angeles County, near Long Beach, California. A primary objective has been to transfer technology that can be applied in other heavy oil formations of the Wilmington Field and other SBC reservoirs, including those under waterflood. The first budget period addressed several producibilitymore » problems in the Tar II-A and Tar V thermal recovery operations that are common in SBC reservoirs. A few of the advanced technologies developed include a three-dimensional (3-D) deterministic geologic model, a 3-D deterministic thermal reservoir simulation model to aid in reservoir management and subsequent post-steamflood development work, and a detailed study on the geochemical interactions between the steam and the formation rocks and fluids. State of the art operational work included drilling and performing a pilot steam injection and production project via four new horizontal wells (2 producers and 2 injectors), implementing a hot water alternating steam (WAS) drive pilot in the existing steamflood area to improve thermal efficiency, installing a 2400-foot insulated, subsurface harbor channel crossing to supply steam to an island location, testing a novel alkaline steam completion technique to control well sanding problems, and starting on an advanced reservoir management system through computer-aided access to production and geologic data to integrate reservoir characterization, engineering, monitoring, and evaluation. The second budget period phase (BP2) continued to implement state-of-the-art operational work to optimize thermal recovery processes, improve well drilling and completion practices, and

  5. AmTAR2: Functional characterization of a honeybee tyramine receptor stimulating adenylyl cyclase activity.

    PubMed

    Reim, Tina; Balfanz, Sabine; Baumann, Arnd; Blenau, Wolfgang; Thamm, Markus; Scheiner, Ricarda

    2017-01-01

    The biogenic monoamines norepinephrine and epinephrine regulate important physiological functions in vertebrates. Insects such as honeybees do not synthesize these neuroactive substances. Instead, they employ octopamine and tyramine for comparable physiological functions. These biogenic amines activate specific guanine nucleotide-binding (G) protein-coupled receptors (GPCRs). Based on pharmacological data obtained on heterologously expressed receptors, α- and β-adrenergic-like octopamine receptors are better activated by octopamine than by tyramine. Conversely, GPCRs forming the type 1 tyramine receptor clade (synonymous to octopamine/tyramine receptors) are better activated by tyramine than by octopamine. More recently, receptors were characterized which are almost exclusively activated by tyramine, thus forming an independent type 2 tyramine receptor clade. Functionally, type 1 tyramine receptors inhibit adenylyl cyclase activity, leading to a decrease in intracellular cAMP concentration ([cAMP] i ). Type 2 tyramine receptors can mediate Ca 2+ signals or both Ca 2+ signals and effects on [cAMP] i . We here provide evidence that the honeybee tyramine receptor 2 (AmTAR2), when heterologously expressed in flpTM cells, exclusively causes an increase in [cAMP] i . The receptor displays a pronounced preference for tyramine over octopamine. Its activity can be blocked by a series of established antagonists, of which mianserin and yohimbine are most efficient. The functional characterization of two tyramine receptors from the honeybee, AmTAR1 (previously named AmTYR1) and AmTAR2, which respond to tyramine by changing cAMP levels in opposite direction, is an important step towards understanding the actions of tyramine in honeybee behavior and physiology, particularly in comparison to the effects of octopamine. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. The role of water content in triboelectric charging of wind-blown sand.

    PubMed

    Gu, Zhaolin; Wei, Wei; Su, Junwei; Yu, Chuck Wah

    2013-01-01

    Triboelectric charging is common in desert sandstorms and dust devils on Earth; however, it remains poorly understood. Here we show a charging mechanism of sands with the adsorbed water on micro-porous surface in wind-blown sand based on the fact that water content is universal but usually a minor component in most particle systems. The triboelectric charging could be resulted due to the different mobility of H(+)/OH(-) between the contacting sands with a temperature difference. Computational fluid dynamics (CFD) and discrete element method (DEM) were used to demonstrate the dynamics of the sand charging. The numerically simulated charge-to-mass ratios of sands and electric field strength established in wind tunnel agreed well with the experimental data. The charging mechanism could provide an explanation for the charging process of all identical granular systems with water content, including Martian dust devils, wind-blown snow, even powder electrification in industrial processes.

  7. Earth-like sand fluxes on Mars.

    PubMed

    Bridges, N T; Ayoub, F; Avouac, J-P; Leprince, S; Lucas, A; Mattson, S

    2012-05-09

    Strong and sustained winds on Mars have been considered rare, on the basis of surface meteorology measurements and global circulation models, raising the question of whether the abundant dunes and evidence for wind erosion seen on the planet are a current process. Recent studies showed sand activity, but could not determine whether entire dunes were moving--implying large sand fluxes--or whether more localized and surficial changes had occurred. Here we present measurements of the migration rate of sand ripples and dune lee fronts at the Nili Patera dune field. We show that the dunes are near steady state, with their entire volumes composed of mobile sand. The dunes have unexpectedly high sand fluxes, similar, for example, to those in Victoria Valley, Antarctica, implying that rates of landscape modification on Mars and Earth are similar.

  8. Design and initial testing of a piezoelectric sensor to quantify aeolian sand transport

    NASA Astrophysics Data System (ADS)

    Raygosa-Barahona, Ruben; Ruiz-Martinez, Gabriel; Mariño-Tapia, Ismael; Heyser-Ojeda, Emilio

    2016-09-01

    This paper describes a sensor for measuring the mass flux of aeolian sand transport based on a low-cost piezo-electric transducer. The device is able to measure time series of aeolian sand transport. Maximum fluxes of 27 mg per second can be achieved. The design includes a sand trap, an electronic amplifier circuit and an embedded system for data collection. A field test was performed, where the basis for signal interpretation and the corresponding measurements of aeolian sand transport are presented. The sensor successfully measures fluxes driven by sea breezes of 10 ms-1, showing the importance of this process for dune-building in the region.

  9. Chemical characterization of the smokes of selected US commercial cigarettes: tar, nicotine, carbon monoxide, oxides of nitrogen, hydrogen cyanide, and acrolein. [32 brands

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jenkins, R.A.; White, S.K.; Griest, W.H.

    Thirty-two brands of US commercial cigarettes were analyzed for their deliveries of tar, nicotine, CO, CO/sub 2/, HCN, NO/sub x/, and acrolein under standard smoking conditions. Per cigarette and per puff deliveries were calculated. The sample suite contained filtered and non-filtered varieties, and relatively popular high, low, and medium tar delivery cigarettes. The range of deliveries of these constituents was considerable. Statistical analysis indicated that the deliveries of nicotine, CO, NO/sub x/, and HCN could usually be estimated to within 50% of their actual delivery if the tar delivery was known. However, brand to brand variation in the constituent ratiosmore » was sufficient so as to preclude the exact calculation of the delivery of one component from that of another.« less

  10. Modeling surficial sand and gravel deposits

    USGS Publications Warehouse

    Bliss, J.D.; Page, N.J.

    1994-01-01

    Mineral-deposit models are an integral part of quantitative mineral-resource assessment. As the focus of mineral-deposit modeling has moved from metals to industrial minerals, procedure has been modified and may be sufficient to model surficial sand and gravel deposits. Sand and gravel models are needed to assess resource-supply analyses for planning future development and renewal of infrastructure. Successful modeling of sand and gravel deposits must address (1) deposit volumes and geometries, (2) sizes of fragments within the deposits, (3) physical characteristics of the material, and (4) chemical composition and chemical reactivity of the material. Several models of sand and gravel volumes and geometries have been prepared and suggest the following: Sand and gravel deposits in alluvial fans have a median volume of 35 million m3. Deposits in all other geologic settings have a median volume of 5.4 million m3, a median area of 120 ha, and a median thickness of 4 m. The area of a sand and gravel deposit can be predicted from volume using a regression model (log [area (ha)] =1.47+0.79 log [volume (million m3)]). In similar fashion, the volume of a sand and gravel deposit can be predicted from area using the regression (log [volume (million m3)]=-1.45+1.07 log [area (ha)]). Classifying deposits by fragment size can be done using models of the percentage of sand, gravel, and silt within deposits. A classification scheme based on fragment size is sufficiently general to be applied anywhere. ?? 1994 Oxford University Press.

  11. The Diversity of Yellow-Related Proteins in Sand Flies (Diptera: Psychodidae)

    PubMed Central

    Sima, Michal; Novotny, Marian; Pravda, Lukas; Sumova, Petra; Rohousova, Iva; Volf, Petr

    2016-01-01

    Yellow-related proteins (YRPs) present in sand fly saliva act as affinity binders of bioamines, and help the fly to complete a bloodmeal by scavenging the physiological signals of damaged cells. They are also the main antigens in sand fly saliva and their recombinant form is used as a marker of host exposure to sand flies. Moreover, several salivary proteins and plasmids coding these proteins induce strong immune response in hosts bitten by sand flies and are being used to design protecting vaccines against Leishmania parasites. In this study, thirty two 3D models of different yellow-related proteins from thirteen sand fly species of two genera were constructed based on the known protein structure from Lutzomyia longipalpis. We also studied evolutionary relationships among species based on protein sequences as well as sequence and structural variability of their ligand-binding site. All of these 33 sand fly YRPs shared a similar structure, including a unique tunnel that connects the ligand-binding site with the solvent by two independent paths. However, intraspecific modifications found among these proteins affects the charges of the entrances to the tunnel, the length of the tunnel and its hydrophobicity. We suggest that these structural and sequential differences influence the ligand-binding abilities of these proteins and provide sand flies with a greater number of YRP paralogs with more nuanced answers to bioamines. All these characteristics allow us to better evaluate these proteins with respect to their potential use as part of anti-Leishmania vaccines or as an antigen to measure host exposure to sand flies. PMID:27812196

  12. The effects of higher cigarette prices on tar and nicotine consumption in a cohort of adult smokers.

    PubMed

    Farrelly, M C; Nimsch, C T; Hyland, A; Cummings, M

    2004-01-01

    The objective of this paper is to estimate the demand for tar and nicotine in cigarettes as a function of cigarette prices in a cohort of cigarette 11,966 smokers followed for 5 years. Data for the analysis come from a longitudinal telephone survey of 11,966 smokers who were interviewed in 1988 and 1993 as part of the Community Intervention Trial for Smoking Cessation (COMMIT). Separate models are estimated for three age groups to account for differences in levels of addiction and brand loyalty across age. We found that smokers respond to higher cigarette prices by reducing the number of cigarettes smoked per day but also by switching to cigarettes that are higher in tar and nicotine per cigarette. Copyright 2003 John Wiley & Sons, Ltd.

  13. Ocean Sand, Bahamas

    NASA Image and Video Library

    2011-04-20

    NASA image acquired January 17, 2001 Though the above image may resemble a new age painting straight out of an art gallery in Venice Beach, California, it is in fact a satellite image of the sands and seaweed in the Bahamas. The image was taken by the Enhanced Thematic Mapper plus (ETM+) instrument aboard the Landsat 7 satellite. Tides and ocean currents in the Bahamas sculpted the sand and seaweed beds into these multicolored, fluted patterns in much the same way that winds sculpted the vast sand dunes in the Sahara Desert. Image courtesy Serge Andrefouet, University of South Florida Instrument: Landsat 7 - ETM+ Credit: NASA/GSFC/Landsat NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Join us on Facebook

  14. Critical State of Sand Matrix Soils

    PubMed Central

    Marto, Aminaton; Tan, Choy Soon; Makhtar, Ahmad Mahir; Kung Leong, Tiong

    2014-01-01

    The Critical State Soil Mechanic (CSSM) is a globally recognised framework while the critical states for sand and clay are both well established. Nevertheless, the development of the critical state of sand matrix soils is lacking. This paper discusses the development of critical state lines and corresponding critical state parameters for the investigated material, sand matrix soils using sand-kaolin mixtures. The output of this paper can be used as an interpretation framework for the research on liquefaction susceptibility of sand matrix soils in the future. The strain controlled triaxial test apparatus was used to provide the monotonic loading onto the reconstituted soil specimens. All tested soils were subjected to isotropic consolidation and sheared under undrained condition until critical state was ascertain. Based on the results of 32 test specimens, the critical state lines for eight different sand matrix soils were developed together with the corresponding values of critical state parameters, M, λ, and Γ. The range of the value of M, λ, and Γ is 0.803–0.998, 0.144–0.248, and 1.727–2.279, respectively. These values are comparable to the critical state parameters of river sand and kaolin clay. However, the relationship between fines percentages and these critical state parameters is too scattered to be correlated. PMID:24757417

  15. Sand Type Filters for Swimming Pools. Standard No. 10, Revised October, 1966.

    ERIC Educational Resources Information Center

    National Sanitation Foundation, Ann Arbor, MI.

    Sand type filters are covered in this standard. The filters described are intended to be designed and used specifically for swimming pool water filtration, both public and residential. Included are the basic components which are a necessary part of the sand type filter such as filter housing, upper and lower distribution systems filter media,…

  16. You're standing on it! Coal-tar-based pavement sealcoat and environmental and human health

    USGS Publications Warehouse

    Mahler, Barbara J.; Van Metre, Peter C.

    2013-01-01

    Results from a new study by researchers from Baylor University and the USGS indicate that living adjacent to a coal-tar-sealed pavement is associated with significant increases in estimated excess lifetime cancer risk, and that much of the increased risk occurs during early childhood.

  17. The role of water content in triboelectric charging of wind-blown sand

    PubMed Central

    Gu, Zhaolin; Wei, Wei; Su, Junwei; Yu, Chuck Wah

    2013-01-01

    Triboelectric charging is common in desert sandstorms and dust devils on Earth; however, it remains poorly understood. Here we show a charging mechanism of sands with the adsorbed water on micro-porous surface in wind-blown sand based on the fact that water content is universal but usually a minor component in most particle systems. The triboelectric charging could be resulted due to the different mobility of H+/OH− between the contacting sands with a temperature difference. Computational fluid dynamics (CFD) and discrete element method (DEM) were used to demonstrate the dynamics of the sand charging. The numerically simulated charge-to-mass ratios of sands and electric field strength established in wind tunnel agreed well with the experimental data. The charging mechanism could provide an explanation for the charging process of all identical granular systems with water content, including Martian dust devils, wind-blown snow, even powder electrification in industrial processes. PMID:23434920

  18. Load capacity, failure mode and design criteria investigation of sand jacks : full scale load testing of sand jacks.

    DOT National Transportation Integrated Search

    2008-12-01

    A sand-jack is a sand filled container used as a component of cast-in-place bridge false-work. The sand filler facilitates the removal of the false-work by allowing slow and controlled lowering of the bracing that has become wedged beneath the new br...

  19. Simple stochastic cellular automaton model for starved beds and implications about formation of sand topographic features in terms of sand flux

    NASA Astrophysics Data System (ADS)

    Endo, Noritaka

    2016-12-01

    A simple stochastic cellular automaton model is proposed for simulating bedload transport, especially for cases with a low transport rate and where available sediments are very sparse on substrates in a subaqueous system. Numerical simulations show that the bed type changes from sheet flow through sand patches to ripples as the amount of sand increases; this is consistent with observations in flume experiments and in the field. Without changes in external conditions, the sand flux calculated for a given amount of sand decreases over time as bedforms develop from a flat bed. This appears to be inconsistent with the general understanding that sand flux remains unchanged under the constant-fluid condition, but it is consistent with the previous experimental data. For areas of low sand abundance, the sand flux versus sand amount (flux-density relation) in the simulation shows a single peak with an abrupt decrease, followed by a long tail; this is very similar to the flux-density relation seen in automobile traffic flow. This pattern (the relation between segments of the curve and the corresponding bed states) suggests that sand sheets, sand patches, and sand ripples correspond respectively to the free-flow phase, congested phase, and jam phase of traffic flows. This implies that sand topographic features on starved beds are determined by the degree of interference between sand particles. Although the present study deals with simple cases only, this can provide a simplified but effective modeling of the more complicated sediment transport processes controlled by interference due to contact between grains, such as the pulsatory migration of grain-size bimodal mixtures with repetition of clustering and scattering.

  20. TAR-independent transactivation by Tat in cells derived from the CNS: a novel mechanism of HIV-1 gene regulation.

    PubMed Central

    Taylor, J P; Pomerantz, R; Bagasra, O; Chowdhury, M; Rappaport, J; Khalili, K; Amini, S

    1992-01-01

    The Tat protein of human immunodeficiency virus type 1 (HIV-1) is essential for productive infection and is a potential target for antiviral therapy. Tat, a potent activator of HIV-1 gene expression, serves to greatly increase the rate of transcription directed by the viral promoter. This induction, which seems to be an important component in the progression of acquired immune deficiency syndrome (AIDS), may be due to increased transcriptional initiation, increased transcriptional elongation, or a combination of these processes. Much attention has been focused on the interaction of Tat with a specific RNA target termed TAR (transactivation responsive) which is present in the leader sequence of all HIV-1 mRNAs. This interaction is believed to be an important component of the mechanism of transactivation. In this report we demonstrate that in certain CNS-derived cells Tat is capable of activating HIV-1 through a TAR-independent pathway. A Tat-responsive element is found upstream within the viral promoter that in glial-derived cell lines allows transactivation in the absence of TAR. Deletion mapping and hybrid promoter constructs demonstrate that the newly identified Tat-responsive element corresponds to a sequence within the viral long terminal repeat (LTR) previously identified as the HIV-1 enhancer, or NF-kappa B domain. DNA band-shift analysis reveals NF-kappa B binding activity in glial cells that differs from that present in T lymphoid cells. Further, we observe that TAR-deleted mutants of HIV-1 demonstrate normal late gene expression in glial cells as evidenced by syncytia formation and production of viral p24 antigen.(ABSTRACT TRUNCATED AT 250 WORDS) Images PMID:1505523

  1. 78 FR 19518 - Notice of Availability of Approved Land Use Plan Amendments/Record of Decision for Allocation of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-01

    ...) may call the Federal Information Relay Service (FIRS) at 1-800-877-8339 to contact the above... and development of tar sands. The Environmental Protection Agency published a Notice of Availability...

  2. Cytotoxicity of yellow sand in lung epithelial cells.

    PubMed

    Kim, Y H; Kim, K S; Kwak, N J; Lee, K H; Kweon, S A; Lim, Y

    2003-02-01

    The present study was carried out to observe the cytotoxicity of yellow sand in comparison with silica and titanium dioxide in a rat alveolar type II cell line (RLE-6TN). Yellow sand (China Loess) was obtained from the loess layer in the Gunsu Province of China. The mean particle diameter of yellow sand was about 0.003 +/- 0.001 mm. Major elements of yellow sand were Si(27.7 +/- 0.6%), Al(6.01 +/- 0.17%), and Ca(5.83 +/- 0.23%) in that order. Silica and yellow sand significantly decreased cell viability and increased [Ca2+]i. All three particles increased the generation of H2O2. TiO2 did not change Fenton activity, while silica induced a slight increase of Fenton activity. In contrast, yellow sand induced a significant increase of Fenton activity. Silica, yellow sand and TiO2 induced significant nitrite formations in RLE-6TN cells. Silica showed the highest increase in nitrite formation, while yellow sand induced the least formation of nitrite. Silica and yellow sand increased the release of TNF-a. Based on these results, we suggest that yellow sand can induce cytotoxicity in RLE-6TN cells and reactive oxygen species, Fenton activity and reactive nitrogen species might be involved in this toxicity.

  3. Sand lance: a review of biology and predator relations and annotated bibliography.

    Treesearch

    Martin D. Robards; Mary F. Willson; Robert H. Armstrong; John F. Piatt

    2000-01-01

    Sand lance (Ammodytes) constitute a major prey for at least some populations of over 100 species of consumer, including 40 species of birds, 12 species of marine mammals, 45 species of fishes, and some invertebrates. Variation in the availability of sand lance (and other forage fishes) can have major effects on the breeding success and survival of...

  4. Thermodynamic studies of a series of homologous HIV-1 TAR RNA ligands reveal that loose binders are stronger Tat competitors than tight ones

    PubMed Central

    Pascale, Lise; Azoulay, Stéphane; Di Giorgio, Audrey; Zenacker, Laura; Gaysinski, Marc; Clayette, Pascal; Patino, Nadia

    2013-01-01

    RNA is a major drug target, but the design of small molecules that modulate RNA function remains a great challenge. In this context, a series of structurally homologous ‘polyamide amino acids’ (PAA) was studied as HIV-1 trans-activating response (TAR) RNA ligands. An extensive thermodynamic study revealed the occurence of an enthalpy–entropy compensation phenomenon resulting in very close TAR affinities for all PAA. However, their binding modes and their ability to compete with the Tat fragment strongly differ according to their structure. Surprisingly, PAA that form loose complexes with TAR were shown to be stronger Tat competitors than those forming tight ones, and thermal denaturation studies demonstrated that loose complexes are more stable than tight ones. This could be correlated to the fact that loose and tight ligands induce distinct RNA conformational changes as revealed by circular dichroism experiments, although nuclear magnetic resonance (NMR) experiments showed that the TAR binding site is the same in all cases. Finally, some loose PAA also display promising inhibitory activities on HIV-infected cells. Altogether, these results lead to a better understanding of RNA interaction modes that could be very useful for devising new ligands of relevant RNA targets. PMID:23605042

  5. Rebound of a coal tar creosote plume following partial source zone treatment with permanganate.

    PubMed

    Thomson, N R; Fraser, M J; Lamarche, C; Barker, J F; Forsey, S P

    2008-11-14

    The long-term management of dissolved plumes originating from a coal tar creosote source is a technical challenge. For some sites stabilization of the source may be the best practical solution to decrease the contaminant mass loading to the plume and associated off-site migration. At the bench-scale, the deposition of manganese oxides, a permanganate reaction byproduct, has been shown to cause pore plugging and the formation of a manganese oxide layer adjacent to the non-aqueous phase liquid creosote which reduces post-treatment mass transfer and hence mass loading from the source. The objective of this study was to investigate the potential of partial permanganate treatment to reduce the ability of a coal tar creosote source zone to generate a multi-component plume at the pilot-scale over both the short-term (weeks to months) and the long-term (years) at a site where there is >10 years of comprehensive synoptic plume baseline data available. A series of preliminary bench-scale experiments were conducted to support this pilot-scale investigation. The results from the bench-scale experiments indicated that if sufficient mass removal of the reactive compounds is achieved then the effective solubility, aqueous concentration and rate of mass removal of the more abundant non-reactive coal tar creosote compounds such as biphenyl and dibenzofuran can be increased. Manganese oxide formation and deposition caused an order-of-magnitude decrease in hydraulic conductivity. Approximately 125 kg of permanganate were delivered into the pilot-scale source zone over 35 days, and based on mass balance estimates <10% of the initial reactive coal tar creosote mass in the source zone was oxidized. Mass discharge estimated at a down-gradient fence line indicated >35% reduction for all monitored compounds except for biphenyl, dibenzofuran and fluoranthene 150 days after treatment, which is consistent with the bench-scale experimental results. Pre- and post-treatment soil core data

  6. Identification of Algerian Field-Caught Phlebotomine Sand Fly Vectors by MALDI-TOF MS

    PubMed Central

    Lafri, Ismail; Almeras, Lionel; Bitam, Idir; Caputo, Aurelia; Yssouf, Amina; Forestier, Claire-Lise; Izri, Arezki; Raoult, Didier; Parola, Philippe

    2016-01-01

    Background Phlebotomine sand flies are known to transmit Leishmania parasites, bacteria and viruses that affect humans and animals in many countries worldwide. Precise sand fly identification is essential to prevent phlebotomine-borne diseases. Over the past two decades, progress in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has emerged as an accurate tool for arthropod identification. The objective of the present study was to investigate the usefulness of MALDI-TOF MS as a tool for identifying field-caught phlebotomine. Methodology/Principal Findings Sand flies were captured in four sites in north Algeria. A subset was morphologically and genetically identified. Six species were found in these areas and a total of 28 stored frozen specimens were used for the creation of the reference spectrum database. The relevance of this original method for sand fly identification was validated by two successive blind tests including the morphological identification of 80 new specimens which were stored at -80°C, and 292 unknown specimens, including engorged specimens, which were preserved under different conditions. Intra-species reproducibility and inter-species specificity of the protein profiles were obtained, allowing us to distinguish specimens at the gender level. Querying of the sand fly database using the MS spectra from the blind test groups revealed concordant results between morphological and MALDI-TOF MS identification. However, MS identification results were less efficient for specimens which were engorged or stored in alcohol. Identification of 362 phlebotomine sand flies, captured at four Algerian sites, by MALDI-TOF MS, revealed that the subgenus Larroussius was predominant at all the study sites, except for in M’sila where P. (Phlebotomus) papatasi was the only sand fly species detected. Conclusion The present study highlights the application of MALDI-TOF MS for monitoring sand fly fauna captured in the field

  7. Identification of Algerian Field-Caught Phlebotomine Sand Fly Vectors by MALDI-TOF MS.

    PubMed

    Lafri, Ismail; Almeras, Lionel; Bitam, Idir; Caputo, Aurelia; Yssouf, Amina; Forestier, Claire-Lise; Izri, Arezki; Raoult, Didier; Parola, Philippe

    2016-01-01

    Phlebotomine sand flies are known to transmit Leishmania parasites, bacteria and viruses that affect humans and animals in many countries worldwide. Precise sand fly identification is essential to prevent phlebotomine-borne diseases. Over the past two decades, progress in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has emerged as an accurate tool for arthropod identification. The objective of the present study was to investigate the usefulness of MALDI-TOF MS as a tool for identifying field-caught phlebotomine. Sand flies were captured in four sites in north Algeria. A subset was morphologically and genetically identified. Six species were found in these areas and a total of 28 stored frozen specimens were used for the creation of the reference spectrum database. The relevance of this original method for sand fly identification was validated by two successive blind tests including the morphological identification of 80 new specimens which were stored at -80°C, and 292 unknown specimens, including engorged specimens, which were preserved under different conditions. Intra-species reproducibility and inter-species specificity of the protein profiles were obtained, allowing us to distinguish specimens at the gender level. Querying of the sand fly database using the MS spectra from the blind test groups revealed concordant results between morphological and MALDI-TOF MS identification. However, MS identification results were less efficient for specimens which were engorged or stored in alcohol. Identification of 362 phlebotomine sand flies, captured at four Algerian sites, by MALDI-TOF MS, revealed that the subgenus Larroussius was predominant at all the study sites, except for in M'sila where P. (Phlebotomus) papatasi was the only sand fly species detected. The present study highlights the application of MALDI-TOF MS for monitoring sand fly fauna captured in the field. The low cost, reliability and rapidity of MALDI

  8. Evaluation of ocular irritancy of coal-tar dyes used in cosmetics employing reconstructed human cornea-like epithelium and short time exposure tests.

    PubMed

    Lee, Miri; Nam, Ki Taek; Kim, Jungah; Lim, Song E; Yeon, Sang Hyeon; Lee, Buhyun; Lee, Joo Young; Lim, Kyung-Min

    2017-10-01

    Coal-tar dyes in cosmetics may elicit adverse effects in the skin and eyes. Countries, like the US, have banned the use of coal-tar dyes in cosmetics for the eye area due to the potential for ocular irritation. We evaluated the eye irritation potential of 15 coal-tar dyes permitted as cosmetic ingredients in reconstructed human cornea-like epithelium (RhCEs [EpiOcular™ and MCTT HCE™]) tests and the short time exposure (STE) test. Eosin YS, phloxine B, tetrachlorotetrabromofluorescein, and tetrabromofluorescein were identified as irritants in RhCEs; dibromofluorescein and uranine yielded discrepant results. STE enabled further classification in accordance with the UN Globally Harmonized System of Classification and Labelling of Chemicals, as follows: eosin YS as Cat 2; phloxine B, Cat 1; and tetrachlorotetrabromofluorescein and tetrabromofluorescein, Cat 1/2. STE indicated dibromofluorescein (irritant in EpiOcular™) and uranine (irritant in MCTT HCE™) as No Cat, resulting in the classification of "No prediction can be made." based on bottom-up approach with each model. These results demonstrated that in vitro eye irritation tests can be utilized to evaluate the potential ocular irritancy of cosmetic ingredients and provide significant evidence with which to determine whether precautions should be given for the use of coal-tar dyes in cosmetics or other substances applied to the eye area. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Analysis of wind-blown sand movement over transverse dunes.

    PubMed

    Jiang, Hong; Huang, Ning; Zhu, Yuanjian

    2014-12-01

    Wind-blown sand movement often occurs in a very complicated desert environment where sand dunes and ripples are the basic forms. However, most current studies on the theoretic and numerical models of wind-blown sand movement only consider ideal conditions such as steady wind velocity, flat sand surface, etc. In fact, the windward slope gradient plays a great role in the lift-off and sand particle saltation. In this paper, we propose a numerical model for the coupling effect between wind flow and saltating sand particles to simulate wind-blown sand movement over the slope surface and use the SIMPLE algorithm to calculate wind flow and simulate sands transport by tracking sand particle trajectories. We furthermore compare the result of numerical simulation with wind tunnel experiments. These results prove that sand particles have obvious effect on wind flow, especially that over the leeward slope. This study is a preliminary study on windblown sand movement in a complex terrain, and is of significance in the control of dust storms and land desertification.

  10. Analysis of Wind-blown Sand Movement over Transverse Dunes

    PubMed Central

    Jiang, Hong; Huang, Ning; Zhu, Yuanjian

    2014-01-01

    Wind-blown sand movement often occurs in a very complicated desert environment where sand dunes and ripples are the basic forms. However, most current studies on the theoretic and numerical models of wind-blown sand movement only consider ideal conditions such as steady wind velocity, flat sand surface, etc. In fact, the windward slope gradient plays a great role in the lift-off and sand particle saltation. In this paper, we propose a numerical model for the coupling effect between wind flow and saltating sand particles to simulate wind-blown sand movement over the slope surface and use the SIMPLE algorithm to calculate wind flow and simulate sands transport by tracking sand particle trajectories. We furthermore compare the result of numerical simulation with wind tunnel experiments. These results prove that sand particles have obvious effect on wind flow, especially that over the leeward slope. This study is a preliminary study on windblown sand movement in a complex terrain, and is of significance in the control of dust storms and land desertification. PMID:25434372

  11. Influence of a Reclaimed Sand Addition to Moulding Sand with Furan Resin on Its Impact on the Environment.

    PubMed

    Holtzer, Mariusz; Dańko, Rafał; Kmita, Angelika

    Metalcasting involves having a molten metal poured in a hollow mould to produce metal objects. These moulds are generally made of sand and are chemically bonded, clay-bonded, or even unbounded. There are many binder systems used. Binders based on furfuryl resins constitute currently the highest fraction in the binders no-bake group. Moulding sand, after knocking out the cast, is partially reclaimed, and the remaining part, known as waste foundry sand is used or stored outside the foundry. In this case, the environment hazardous organic compounds and metals can be leached from the moulding sand, thus causing pollution of water and soil. Also during the casting moulds with molten metal, they emit pyrolysis gases containing many different compounds, often dangerous from the BTEX and PAH group, which has adverse impacts on the environment and workers. The article presents the results of research on the impact of the regenerate addition to the moulding sand matrix on emitted gases and the degree of threat to the environment due to leaching of hazardous components. Therefore, for the total assessment of the moulding sands harmfulness, it is necessary to perform investigations concerning the dangerous substances elution into the environment during their management and storage, as well as investigations concerning emissions of hazardous substances (especially from the BTEX and PAHs group) during moulds pouring, cooling, and casting knocking out. Both kinds of investigations indicated that reclaimed sand additions to moulding sands have significantly negative influence on the environment and working conditions.

  12. Smokers' sensory beliefs mediate the relation between smoking a light/low tar cigarette and perceptions of harm.

    PubMed

    Elton-Marshall, Tara; Fong, Geoffrey T; Yong, Hua-Hie; Borland, Ron; Xu, Steve Shaowei; Quah, Anne C K; Feng, Guoze; Jiang, Yuan

    2015-11-01

    The sensory belief that 'light/low tar' cigarettes are smoother can also influence the belief that 'light/low tar' cigarettes are less harmful. However, the 'light' concept is one of several factors influencing beliefs. No studies have examined the impact of the sensory belief about one's own brand of cigarettes on perceptions of harm. The current study examines whether a smoker's sensory belief that their brand is smoother is associated with the belief that their brand is less harmful and whether sensory beliefs mediate the relation between smoking a 'light/low tar' cigarette and relative perceptions of harm among smokers in China. Data are from 5209 smokers who were recruited using a stratified multistage sampling design and participated in Wave 3 of the International Tobacco Control (ITC) China Survey, a face-to-face survey of adult smokers and non-smokers in seven cities. Smokers who agreed that their brand of cigarettes was smoother were significantly more likely to say that their brand of cigarettes was less harmful (p<0.001, OR=6.86, 95% CI 5.64 to 8.33). Mediational analyses using the bootstrapping procedure indicated that both the direct effect of 'light/low tar' cigarette smokers on the belief that their cigarettes are less harmful (b=0.24, bootstrapped bias corrected 95% CI 0.13 to 0.34, p<0.001) and the indirect effect via their belief that their cigarettes are smoother were significant (b=0.32, bootstrapped bias-corrected 95% CI 0.28 to 0.37, p<0.001), suggesting that the mediation was partial. These results demonstrate the importance of implementing tobacco control policies that address the impact that cigarette design and marketing can have in capitalising on the smoker's natural associations between smoother sensations and lowered perceptions of harm. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  13. Northern Sand Sea

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    Our topic for the weeks of April 4 and April 11 is dunes on Mars. We will look at the north polar sand sea and at isolated dune fields at lower latitudes. Sand seas on Earth are often called 'ergs,' an Arabic name for dune field. A sand sea differs from a dune field in two ways: 1) a sand sea has a large regional extent, and 2) the individual dunes are large in size and complex in form.

    This VIS image was taken at 82 degrees North latitude during Northern spring. The image is completely dominated by dunes. In sand seas, it is very common for a single type of dune to occur, and for a single predominate wind to control the alignment of the dunes.

    Image information: VIS instrument. Latitude 82.2, Longitude 152.5 East (207.5 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  14. An annotated list of the mayflies, stoneflies, and caddisflies of the Sand Creek basin, Great Sand Dunes National Park and Preserve, Colorado, 2004 and 2005

    USGS Publications Warehouse

    Zuellig, Robert E.; Kondratieff, Boris C.; Ruiter, David E.; Thorp, Richard A.

    2006-01-01

    The U.S. Geological Survey, in conjunction with the Great Sand Dunes National Park and Preserve and its cooperators, did an extensive inventory of certain targeted aquatic-insect groups in the Sand Creek Basin, Great Sand Dunes National Park and Preserve, to establish a species list for future monitoring efforts. Study sites were established to monitor these groups following disturbance events. Such potential disturbances may include, but are not limited to, chemical treatment of perennial stream reaches to remove nonnative fishes and the subsequent reintroduction of native fish species, increased public use of backcountry habitat (such as hiking and fishing), and natural disturbances such as fire. This report is an annotated list of the mayflies, stoneflies, and caddisflies found in the Sand Creek Basin, Great Sand Dunes National Park and Preserve, 2004 and 2005. The primary objective of the study was to qualitatively inventory target aquatic-insect groups in perennial streams, and selected unique standing-water habitats, such as springs, and wetlands associated with the Sand Creek Basin. Efforts focused on documenting the presence of aquatic-insect species within the following taxonomic groups: Ephemeroptera (mayflies), Plecoptera (stoneflies), and Trichoptera (caddisflies). These insect orders were chosen because published species accounts, geographic distribution, and identification keys exist for many Colorado species. Given the extent of available information for these groups, there existed a potential for identifying new species and documenting range extensions of known species.

  15. Ganges Chasma Sand Sheet

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    Our topic for the weeks of April 4 and April 11 is dunes on Mars. We will look at the north polar sand sea and at isolated dune fields at lower latitudes. Sand seas on Earth are often called 'ergs,' an Arabic name for dune field. A sand sea differs from a dune field in two ways: 1) a sand sea has a large regional extent, and 2) the individual dunes are large in size and complex in form.

    Today's sand sheet is located in the Ganges Chasma portion of Valles Marineris. As with yesterday's image, note that the dune forms are seen only at the margin and that the interior of the sand sheet at this resolution appears to completely lack dune forms.

    Image information: VIS instrument. Latitude -6.4, Longitude 310.7 East (49.3 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  16. 40 CFR 60.101a - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... suspended in a fluidized bed to improve feedstock quality for additional processing and the catalyst or... the oils derived from tar sands, shale, and coal. Petroleum refinery means any facility engaged in...

  17. Sands at Gusev Crater, Mars

    NASA Astrophysics Data System (ADS)

    Cabrol, Nathalie A.; Herkenhoff, Kenneth; Knoll, Andrew H.; Farmer, Jack; Arvidson, Raymond; Grin, Edmond; Li, Ronxing; Fenton, Lori; Cohen, Barbara; Bell, James F.; Aileen Yingst, R.

    2014-05-01

    Processes, environments, and the energy associated with the transport and deposition of sand at Gusev Crater are characterized at the microscopic scale through the comparison of statistical moments for particle size and shape distributions. Bivariate and factor analyses define distinct textural groups at 51 sites along the traverse completed by the Spirit rover as it crossed the plains and went into the Columbia Hills. Fine-to-medium sand is ubiquitous in ripples and wind drifts. Most distributions show excess fine material, consistent with a predominance of wind erosion over the last 3.8 billion years. Negative skewness at West Valley is explained by the removal of fine sand during active erosion, or alternatively, by excess accumulation of coarse sand from a local source. The coarse to very coarse sand particles of ripple armors in the basaltic plains have a unique combination of size and shape. Their distribution display significant changes in their statistical moments within the ~400 m that separate the Columbia Memorial Station from Bonneville Crater. Results are consistent with aeolian and/or impact deposition, while the elongated and rounded shape of the grains forming the ripples, as well as their direction of origin, could point to Ma'adim Vallis as a possible source. For smaller particles on the traverse, our findings confirm that aeolian processes have dominated over impact and other processes to produce sands with the observed size and shape patterns across a spectrum of geologic (e.g., ripples and plains soils) and aerographic settings (e.g., wind shadows).

  18. Sands at Gusev Crater, Mars

    USGS Publications Warehouse

    Cabrol, Nathalie A.; Herkenhoff, Kenneth E.; Knoll, Andrew H.; Farmer, Jack D.; Arvidson, Raymond E.; Grin, E.A.; Li, Ron; Fenton, Lori; Cohen, B.; Bell, J.F.; Yingst, R. Aileen

    2014-01-01

    Processes, environments, and the energy associated with the transport and deposition of sand at Gusev Crater are characterized at the microscopic scale through the comparison of statistical moments for particle size and shape distributions. Bivariate and factor analyses define distinct textural groups at 51 sites along the traverse completed by the Spirit rover as it crossed the plains and went into the Columbia Hills. Fine-to-medium sand is ubiquitous in ripples and wind drifts. Most distributions show excess fine material, consistent with a predominance of wind erosion over the last 3.8 billion years. Negative skewness at West Valley is explained by the removal of fine sand during active erosion, or alternatively, by excess accumulation of coarse sand from a local source. The coarse to very coarse sand particles of ripple armors in the basaltic plains have a unique combination of size and shape. Their distribution display significant changes in their statistical moments within the ~400 m that separate the Columbia Memorial Station from Bonneville Crater. Results are consistent with aeolian and/or impact deposition, while the elongated and rounded shape of the grains forming the ripples, as well as their direction of origin, could point to Ma'adim Vallis as a possible source. For smaller particles on the traverse, our findings confirm that aeolian processes have dominated over impact and other processes to produce sands with the observed size and shape patterns across a spectrum of geologic (e.g., ripples and plains soils) and aerographic settings (e.g., wind shadows).

  19. Mineral resource of the month: industrial sand and gravel

    USGS Publications Warehouse

    Dolley, Thomas

    2007-01-01

    With many diverse uses, industrial sand and gravel, also known as silica sand, is one of the most important nonmetallic minerals in the world. Industrial sand and gravel is a mining industry term used for sands that have a very high percentage of silicon dioxide, or greater than 95 percent quartz. Deposits of industrial sand and gravel can be found virtually everywhere on Earth, but are less widespread than deposits of common construction sand and gravel. Industrial sand and gravel is distinctive in grain size, hardness, inertness and resistance to high temperature and chemical action. Beverage containers, fiberglass insulation, fiber-optic cables and light bulbs are just some of today’s many products produced from industrial sand and gravel.

  20. DNA barcoding for the identification of sand fly species (Diptera, Psychodidae, Phlebotominae) in Colombia.

    PubMed

    Contreras Gutiérrez, María Angélica; Vivero, Rafael J; Vélez, Iván D; Porter, Charles H; Uribe, Sandra

    2014-01-01

    Sand flies include a group of insects that are of medical importance and that vary in geographic distribution, ecology, and pathogen transmission. Approximately 163 species of sand flies have been reported in Colombia. Surveillance of the presence of sand fly species and the actualization of species distribution are important for predicting risks for and monitoring the expansion of diseases which sand flies can transmit. Currently, the identification of phlebotomine sand flies is based on morphological characters. However, morphological identification requires considerable skills and taxonomic expertise. In addition, significant morphological similarity between some species, especially among females, may cause difficulties during the identification process. DNA-based approaches have become increasingly useful and promising tools for estimating sand fly diversity and for ensuring the rapid and accurate identification of species. A partial sequence of the mitochondrial cytochrome oxidase gene subunit I (COI) is currently being used to differentiate species in different animal taxa, including insects, and it is referred as a barcoding sequence. The present study explored the utility of the DNA barcode approach for the identification of phlebotomine sand flies in Colombia. We sequenced 700 bp of the COI gene from 36 species collected from different geographic localities. The COI barcode sequence divergence within a single species was <2% in most cases, whereas this divergence ranged from 9% to 26.6% among different species. These results indicated that the barcoding gene correctly discriminated among the previously morphologically identified species with an efficacy of nearly 100%. Analyses of the generated sequences indicated that the observed species groupings were consistent with the morphological identifications. In conclusion, the barcoding gene was useful for species discrimination in sand flies from Colombia.

  1. DNA Barcoding for the Identification of Sand Fly Species (Diptera, Psychodidae, Phlebotominae) in Colombia

    PubMed Central

    Contreras Gutiérrez, María Angélica; Vivero, Rafael J.; Vélez, Iván D.; Porter, Charles H.; Uribe, Sandra

    2014-01-01

    Sand flies include a group of insects that are of medical importance and that vary in geographic distribution, ecology, and pathogen transmission. Approximately 163 species of sand flies have been reported in Colombia. Surveillance of the presence of sand fly species and the actualization of species distribution are important for predicting risks for and monitoring the expansion of diseases which sand flies can transmit. Currently, the identification of phlebotomine sand flies is based on morphological characters. However, morphological identification requires considerable skills and taxonomic expertise. In addition, significant morphological similarity between some species, especially among females, may cause difficulties during the identification process. DNA-based approaches have become increasingly useful and promising tools for estimating sand fly diversity and for ensuring the rapid and accurate identification of species. A partial sequence of the mitochondrial cytochrome oxidase gene subunit I (COI) is currently being used to differentiate species in different animal taxa, including insects, and it is referred as a barcoding sequence. The present study explored the utility of the DNA barcode approach for the identification of phlebotomine sand flies in Colombia. We sequenced 700 bp of the COI gene from 36 species collected from different geographic localities. The COI barcode sequence divergence within a single species was <2% in most cases, whereas this divergence ranged from 9% to 26.6% among different species. These results indicated that the barcoding gene correctly discriminated among the previously morphologically identified species with an efficacy of nearly 100%. Analyses of the generated sequences indicated that the observed species groupings were consistent with the morphological identifications. In conclusion, the barcoding gene was useful for species discrimination in sand flies from Colombia. PMID:24454877

  2. A preliminary source-to-sink sediment budget for aeolian sands

    NASA Astrophysics Data System (ADS)

    Sebe, Krisztina; Csillag, Gábor; Timár, Gábor; Jámbor, Áron

    2015-04-01

    constituted dominantly by the Upper Miocene sediments, subordinately by older clastics. The final amount of sand possibly eroded by the wind from the area was calculated by reducing this volume through estimating the portion of sand in the lacustrine succession and the ratio of aeolian and fluvial erosion. Aeolian sand volumes of the sink were calculated using borehole data from publications and original borehole documentations. This approach contains several error sources, including uncertainties in the position of the envelope surface, varying quality of borehole documentations or the distribution of sampling points. As a result, the estimated error margin of the missing volume computation is up to 50% and the provided value is rather a minimum estimation. A similar value can be valid for the sink area. The calculations showed that sand volumes of the source and sink areas are comparable, with the eroded material being about one third to a half of that of the deposited amount (somewhere below 150 km3 and between 300-400 km3, respectively). This result supports the idea that Transdanubia is an important source area of the Kiskunság blown sand field. The portion of sand in the sink not accounted for by the present estimation can be derived from two sources. Probably more blown sand had been delivered to the sink from areas even more upwind from the Transdanubian Range (Danube Basin), now not included in the calculations. The floodplain of the Danube may have also provided sediments, but mostly only in the Late Pleistocene, when the river had already occupied its modern course upwind of the Kiskunság area. Work has been supported by the OTKA projects K 106197 and NK83400.

  3. Full scale load testing of sand-jacks.

    DOT National Transportation Integrated Search

    2006-06-01

    A sand-jack is a sand filled container used as a component of cast-in-place bridge false-work. The sand filler facilitates the removal of the false-work by allowing slow and controlled lowering of the bracing that has become wedged beneath the new br...

  4. Study on sand particles creep model and open pit mine landslide mechanism caused by sand fatigue liquefaction

    NASA Astrophysics Data System (ADS)

    Du, Dong-Ning; Wang, Lai-Gui; Zhang, Xiang-Dong; Zhang, Shu-Kun

    2017-06-01

    The sand particles in the sand - rock composite slope of the open pit mine occurs creep deformation and fatigue liquefaction under the action of vehicle load vibration and hydraulic gradient, which causes landslide geological disasters and it destroys the surface environment. To reveal the mechanism, a mechanics model based on the model considering the soil structural change with a new “plastic hinge” element is developed, to improve its constitutive and creep curve equations. Data from sand creep experiments are used to identify the parameters in the model and to validate the model. The results show that the mechanical model can describe the rotation progress between the sand particles, disclose the negative acceleration creep deformation stage during the third phase, and require fewer parameters while maintaining accuracy. It provides a new creep model considering rotation to analyze sand creep mechanism, which provides a theoretical basis for revealing the open pit mine landslide mechanism induced by creep deformation and fatigue liquefaction of sandy soil.

  5. Characterisation of dense non-aqueous phase liquids of coal tar using comprehensive two-dimensional gas chromatography coupled with time of flight mass spectrometry.

    NASA Astrophysics Data System (ADS)

    Gauchotte-Lindsay, Caroline; McGregor, Laura; Richards, Phil; Kerr, Stephanie; Glenn, Aliyssa; Thomas, Russell; Kalin, Robert

    2013-04-01

    Comprehensive two-dimensional gas chromatography (GCxGC) is a recently developed analytical technique in which two capillary columns with different stationary phases are placed in series enabling planar resolution of the analytes. The resolution power of GCxGC is one order of magnitude higher than that of one dimension gas chromatography. Because of its high resolution capacity, the use of GCxGC for complex environmental samples such as crude oils, petroleum derivatives and polychlorinated biphenyls mixtures has rapidly grown in recent years. We developed a one-step method for the forensic analysis of coal tar dense non-aqueous phase liquids (DNAPLs) from former manufactured gas plant (FMGP) sites. Coal tar is the by-product of the gasification of coal for heating and lighting and it is composed of thousands of organic and inorganic compounds. Before the boom of natural gases and oils, most towns and cities had one or several manufactured gas plants that have, in many cases, left a devastating environmental print due to coal tar contamination. The fate of coal tar DNAPLs, which can persist in the environment for more than a hundred years, is therefore of crucial interest. The presented analytical method consists of a unique clean-up/ extraction stage by pressurized liquid extraction and a single analysis of its organic chemical composition using GCxGC coupled with time of flight mass spectrometry (TOFMS). The chemical fingerprinting is further improved by derivatisation by N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) of the tar compounds containing -OH functions such as alcohols and carboxylic acids. We present here how, using the logical order of elution in GCxGC-TOFMS system, 1) the identification of never before observed -OH containing compounds is possible and 2) the isomeric selectivity of an oxidation reaction on a DNAPL sample can be revealed. Using samples collected at various FMGP sites, we demonstrate how this GCxGC method enables the simultaneous

  6. Use of sand wave habitats by silver hake

    USGS Publications Warehouse

    Auster, P.J.; Lindholm, J.; Schaub, S.; Funnell, G.; Kaufman, L.S.; Valentine, P.C.

    2003-01-01

    Silver hake Merluccius bilinearis are common members of fish communities in sand wave habitats on Georges Bank and on Stellwagen Bank in the Gulf of Maine. Observations of fish size v. sand wave period showed that silver hake are not randomly distributed within sand wave landscapes. Regression analyses showed a significant positive relationship between sand wave period and fish length. Correlation coefficients, however, were low, suggesting other interactions with sand wave morphology, the range of current velocities, and available prey may also influence their distribution. Direct contact with sand wave habitats varied over diel periods, with more fish resting on the seafloor during daytime than at night. Social foraging, in the form of polarized groups of fish swimming in linear formations during crepuscular and daytime periods, was also observed. Sand wave habitats may provide shelter from current flows and mediate fish-prey interactions. ?? 2003 The Fisheries Society of the British Isles.

  7. Blending foundry sands with soil: Effect on dehydrogenase activity.

    PubMed

    Dungan, Robert S; Kukier, Urzsula; Lee, Brad

    2006-03-15

    Each year U.S. foundries landfill several million tons of sand that can no longer be used to make metalcasting molds and cores. A possible use for these materials is as an ingredient in manufactured soils; however, potentially harmful metals and resin binders (used to make cores) may adversely impact the soil microbial community. In this study, the dehydrogenase activity (DHA) of soil amended with molding sand (clay-coated sand known as "green sand") or core sands at 10%, 30%, and 50% (dry wt.) was determined. The green sands were obtained from iron, aluminum, and brass foundries; the core sands were made with phenol-formaldehyde or furfuryl alcohol based resins. Overall, incremental additions of these sands resulted in a decrease in the DHA which lasted throughout the 12-week experimental period. A brass green sand, which contained high concentrations of Cu, Pb, and Zn, severely impacted the DHA. By week 12 no DHA was detected in the 30% and 50% treatments. In contrast, the DHA in soil amended with an aluminum green sand was 2.1 times higher (all blending ratios), on average, at week 4 and 1.4 times greater (30% and 50% treatments only) than the controls by week 12. In core sand-amended soil, the DHA results were similar to soils amended with aluminum and iron green sands. Increased activity in some treatments may be a result of the soil microorganisms utilizing the core resins as a carbon source. The DHA assay is a sensitive indicator of environmental stress caused by foundry sand constituents and may be useful to assess which foundry sands are suitable for beneficial use in the environment.

  8. Design and application of BIM based digital sand table for construction management

    NASA Astrophysics Data System (ADS)

    Fuquan, JI; Jianqiang, LI; Weijia, LIU

    2018-05-01

    This paper explores the design and application of BIM based digital sand table for construction management. Aiming at the demands and features of construction management plan for bridge and tunnel engineering, the key functional features of digital sand table should include three-dimensional GIS, model navigation, virtual simulation, information layers, and data exchange, etc. That involving the technology of 3D visualization and 4D virtual simulation of BIM, breakdown structure of BIM model and project data, multi-dimensional information layers, and multi-source data acquisition and interaction. Totally, the digital sand table is a visual and virtual engineering information integrated terminal, under the unified data standard system. Also, the applications shall contain visual constructing scheme, virtual constructing schedule, and monitoring of construction, etc. Finally, the applicability of several basic software to the digital sand table is analyzed.

  9. Mineralization Of PAHs In Coal-Tar Impacted Aquifer Sediments And Associated Microbial Community Structure Investigated With FISH

    EPA Science Inventory

    The microbial community structure and mineralization of polycyclic aromatic hydrocarbons (PAHs) in a coal-tar contaminated aquifer were investigated spatially using fluorescence in situ hybridization (FISH) and in laboratory-scale incubations of the aquifer sediments. DAPI-detect...

  10. Structural insights into the cTAR DNA recognition by the HIV-1 nucleocapsid protein: role of sugar deoxyriboses in the binding polarity of NC

    PubMed Central

    Bazzi, Ali; Zargarian, Loussiné; Chaminade, Françoise; Boudier, Christian; De Rocquigny, Hughes; René, Brigitte; Mély, Yves; Fossé, Philippe; Mauffret, Olivier

    2011-01-01

    An essential step of the reverse transcription of the HIV-1 genome is the first strand transfer that requires the annealing of the TAR RNA hairpin to the cTAR DNA hairpin. HIV-1 nucleocapsid protein (NC) plays a crucial role by facilitating annealing of the complementary hairpins. Using nuclear magnetic resonance and gel retardation assays, we investigated the interaction between NC and the top half of the cTAR DNA (mini-cTAR). We show that NC(11-55) binds the TGG sequence in the lower stem that is destabilized by the adjacent internal loop. The 5′ thymine interacts with residues of the N-terminal zinc knuckle and the 3′ guanine is inserted in the hydrophobic plateau of the C-terminal zinc knuckle. The TGG sequence is preferred relative to the apical and internal loops containing unpaired guanines. Investigation of the DNA–protein contacts shows the major role of hydrophobic interactions involving nucleobases and deoxyribose sugars. A similar network of hydrophobic contacts is observed in the published NC:DNA complexes, whereas NC contacts ribose differently in NC:RNA complexes. We propose that the binding polarity of NC is related to these contacts that could be responsible for the preferential binding to single-stranded nucleic acids. PMID:21227929

  11. Water quality and bathymetry of Sand Lake, Anchorage, Alaska

    USGS Publications Warehouse

    Donaldson, Donald E.

    1976-01-01

    Sand Lake, a dimictic lowland lake in Anchorage, Alaska, has recently become as urban lake. Analyses indicate that the lake is oligotrophic, having low dissolved solids and nutrient concentrations. Snowmelt runoff from an adjacent residential area, however, has a dissolved-solids concentration 10 times that of the main body of Sand Lake. Lead concentrations in the runoff exceed known values from other water in the ANchorage area, including water samples taken beneath landfills. The volume of the snowmelt runoff has not been measured. The data presented can be used as a baseline for water-resource management. (Woodard-USGS)

  12. Complexity confers stability: Climate variability, vegetation response and sand transport on longitudinal sand dunes in Australia's deserts

    NASA Astrophysics Data System (ADS)

    Hesse, Paul P.; Telfer, Matt W.; Farebrother, Will

    2017-04-01

    The relationship between antecedent precipitation, vegetation cover and sand movement on sand dunes in the Simpson and Strzelecki Deserts was investigated by repeated (up to four) surveys of dune crest plots (≈25 × 25 m) over a drought cycle (2002-2012) in both winter (low wind) and spring (high wind). Vegetation varied dramatically between surveys on vegetated and active dune crests. Indices of sand movement had significant correlations with vegetation cover: the depth of loose sand has a strong inverse relationship with crust (cyanobacterial and/or physical) while the area covered by ripples has a strong inverse relationship with the areal cover of vascular plants. However, the relationship between antecedent rainfall and vegetation cover was found to be complex. We tentatively identify two thresholds; (1) >10 mm of rainfall in the preceding 90 days leads to rapid and near total cover of crust and/or small plants <50 cm tall, and (2) >400 mm of rainfall in the preceding three years leads to higher cover of persistent and longer-lived plants >50 cm tall. These thresholds were used to predict days of low vegetation cover on dune crests. The combination of seasonality of predicted bare-crest days, potential sand drift and resultant sand drift direction explains observed patterns of sand drift on these dunes. The complex vegetation and highly variable rainfall regime confer meta-stability on the dunes through the range of responses to different intervals of antecedent rainfall and non-linear growth responses. This suggests that the geomorphic response of dunes to climate variation is complex and non-linear.

  13. Sand wave fields beneath the Loop Current, Gulf of Mexico: Reworking of fan sands

    USGS Publications Warehouse

    Kenyon, Neil H.; Akhmetzhanov, A.M.; Twichell, D.C.

    2002-01-01

    Extensive fields of large barchan-like sand waves and longitudinal sand ribbons have been mapped by deep-towed SeaMARC IA sidescan sonar on part of the middle and lower Mississippi Fan that lies in about 3200 m of water. The area is beneath the strongly flowing Loop Current. The bedforms have not been adequately sampled but probably consist of winnowed siliciclastic-foraminiferal sands. The size (about 200 m from wingtip to wingtip) and shape of the large barchans is consistent with a previously observed peak current speed of 30 cm/s, measured 25 m above the seabed. The types of small-scale bedforms and the scoured surfaces of chemical crusts, seen on nearby bottom photographs, indicate that near-bed currents in excess of 30 cm/s may sometimes occur. At the time of the survey the sand transport direction was to the northwest, in the opposite direction to the Loop Current but consistent with there being a deep boundary current along the foot of the Florida Escarpment. Some reworking of the underlying sandy turbidites and debris flow deposits is apparent on the sidescan sonar records. Reworking by deep-sea currents, resulting in erosion and in deposits characterised by coarsening upwards structures and cross-bedding, is a process that has been proposed for sand found in cores in shallower parts of the Gulf of Mexico. This process is more widespread than hitherto supposed. 

  14. Experimental study of optimal self compacting concrete with spent foundry sand as partial replacement for M-sand using Taguchi approach

    NASA Astrophysics Data System (ADS)

    Nirmala, D. B.; Raviraj, S.

    2016-06-01

    This paper presents the application of Taguchi approach to obtain optimal mix proportion for Self Compacting Concrete (SCC) containing spent foundry sand and M-sand. Spent foundry sand is used as a partial replacement for M-sand. The SCC mix has seven control factors namely, Coarse aggregate, M-sand with Spent Foundry sand, Cement, Fly ash, Water, Super plasticizer and Viscosity modifying agent. Modified Nan Su method is used to proportion the initial SCC mix. L18 (21×37) Orthogonal Arrays (OA) with the seven control factors having 3 levels is used in Taguchi approach which resulted in 18 SCC mix proportions. All mixtures are extensively tested both in fresh and hardened states to verify whether they meet the practical and technical requirements of SCC. The quality characteristics considering "Nominal the better" situation is applied to the test results to arrive at the optimal SCC mix proportion. Test results indicate that the optimal mix satisfies the requirements of fresh and hardened properties of SCC. The study reveals the feasibility of using spent foundry sand as a partial replacement of M-sand in SCC and also that Taguchi method is a reliable tool to arrive at optimal mix proportion of SCC.

  15. Hydrocarbon recovery from diatomite

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Scinta, J.

    1984-05-15

    Supercritical extraction of diatomaceous earth results in a much more significant improvement in hydrocarbon recovery over Fischer retorting than achievable with tar sands. Process and apparatus for supercritical extraction of diatomaceous earth are disclosed.

  16. Sand lance: A review of biology and predator relations and annotated bibliography

    USGS Publications Warehouse

    Robards, Martin D.; Willson, Mary F.; Armstrong, Robert H.; Piatt, John F.

    1999-01-01

    Six species of sand lance (Ammodytes) in temperate and boreal regions are currently recognized. Sand lance can occupy a wide range of environmental conditions, but all appear to be dormant predominantly in winter, and one species is in summer also. They lack a swim bladder and spend much of their time buried in specific substrates. Copepods are the primary food. Spawning usually occurs in fall or winter (although some species also spawn in spring), eggs are demersal, and larvae may hatch at times of low food abundance. Sand lance usually occur in schools and are regarded as a relatively high-quality forage fish.Sand lance constitute a major prey for at least some populations of over 100 species of consumer, including 40 species of birds, 12 species of marine mammals, 45 species of fishes, and some invertebrates. Variation in the availability of sand lance (and other forage fishes) can have major effects on the breeding success and survival of their predators. Commercial fishing and other pressures on sand lance populations potentially have ramifying effects on many species of wildlife.The bibliography contains over 1,700 references on the family Ammodytidae, with an emphasis on the genus Ammodytes. Keywords are provided for each reference and have been further organized into taxonomic, geographic, subject, and predator indexes.

  17. Dandruff, seborrheic dermatitis, and psoriasis drug products containing coal tar and menthol for over-the-counter human use; amendment to the monograph. Final rule

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    2006-03-15

    The Food and Drug Administration (FDA) is issuing a final rule amending the final monograph (FM) for over-the-counter (OTC) dandruff, seborrheic dermatitis, and psoriasis drug products to include the combination of 1.8 percent coal tar solution and 1.5 percent menthol in a shampoo drug product to control dandruff. FDA did not receive any comments or data in response to its previously proposed rule to include this combination. This final rule is part of FDA's ongoing review of OTC drug products.

  18. Shortening the HIV-1 TAR RNA Bulge by a Single Nucleotide Preserves Motional Modes over a Broad Range of Time Scales.

    PubMed

    Merriman, Dawn K; Xue, Yi; Yang, Shan; Kimsey, Isaac J; Shakya, Anisha; Clay, Mary; Al-Hashimi, Hashim M

    2016-08-16

    Helix-junction-helix (HJH) motifs are flexible building blocks of RNA architecture that help define the orientation and dynamics of helical domains. They are also frequently involved in adaptive recognition of proteins and small molecules and in the formation of tertiary contacts. Here, we use a battery of nuclear magnetic resonance techniques to examine how deleting a single bulge residue (C24) from the human immunodeficiency virus type 1 (HIV-1) transactivation response element (TAR) trinucleotide bulge (U23-C24-U25) affects dynamics over a broad range of time scales. Shortening the bulge has an effect on picosecond-to-nanosecond interhelical and local bulge dynamics similar to that casued by increasing the Mg(2+) and Na(+) concentration, whereby a preexisting two-state equilibrium in TAR is shifted away from a bent flexible conformation toward a coaxial conformation, in which all three bulge residues are flipped out and flexible. Surprisingly, the point deletion minimally affects microsecond-to-millisecond conformational exchange directed toward two low-populated and short-lived excited conformational states that form through reshuffling of bases pairs throughout TAR. The mutant does, however, adopt a slightly different excited conformational state on the millisecond time scale, in which U23 is intrahelical, mimicking the expected conformation of residue C24 in the excited conformational state of wild-type TAR. Thus, minor changes in HJH topology preserve motional modes in RNA occurring over the picosecond-to-millisecond time scales but alter the relative populations of the sampled states or cause subtle changes in their conformational features.

  19. Murzuk Sand Sea, Sahara Desert, Libya, Africa

    NASA Image and Video Library

    1993-01-19

    STS054-152-189 (13-19 Jan. 1993) --- This near-vertical color photograph shows the very diverse landscape that is part of the great Sahara Desert of north Africa. Specifically, the vast expanse of sand dunes, located in the extreme southwestern corner of Libya, is known as the Murzuk Sand Sea. Close inspection of this photograph shows the agricultural village of Murzuk as evidenced by the numerous center pivot irrigation patterns at the edge of the Murzuk Sand Sea. The very rugged, dissected terrain to the west of this sand sea is the eastern tip of the Tassili N'ajjer Mountains and the Tadrart Plateau that are in neighboring Algeria. Several smaller areas of sand dunes are interspersed between the major areas of rock outcrops. The photograph was taken with a Linhof camera.

  20. Functional analysis of a Wheat Homeodomain protein, TaR1, reveals that host chromatin remodelling influences the dynamics of the switch to necrotrophic growth in the phytopathogenic fungus Zymoseptoria tritici.

    PubMed

    Lee, Jack; Orosa, Beatriz; Millyard, Linda; Edwards, Martin; Kanyuka, Kostya; Gatehouse, Angharad; Rudd, Jason; Hammond-Kosack, Kim; Pain, Naomi; Sadanandom, Ari

    2015-04-01

    A distinguishing feature of Septoria leaf blotch disease in wheat is the long symptomless growth of the fungus amongst host cells followed by a rapid transition to necrotrophic growth resulting in disease lesions. Global reprogramming of host transcription marks this switch to necrotrophic growth. However no information exists on the components that bring about host transcriptional reprogramming. Gene-silencing, confocal-imaging and protein-protein interaction assays where employed to identify a plant homeodomain (PHD) protein, TaR1 in wheat that plays a critical role during the transition from symptomless to necrotrophic growth of Septoria. TaR1-silenced wheat show earlier symptom development upon Septoria infection but reduced fungal sporulation indicating that TaR1 is key for prolonging the symptomless phase and facilitating Septoria asexual reproduction. TaR1 is localized to the nucleus and binds to wheat Histone 3. Trimethylation of Histone 3 at lysine 4 (H3K4) and lysine 36 (H3K36) are found on open chromatin with actively transcribed genes, whereas methylation of H3K27 and H3K9 are associated with repressed loci. TaR1 specifically recognizes dimethylated and trimethylated H3K4 peptides suggesting that it regulates transcriptional activation at open chromatin. We conclude that TaR1 is an important component for the pathogen life cycle in wheat that promotes successful colonization by Septoria. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  1. Investigation of guided wave propagation and attenuation in pipe buried in sand

    NASA Astrophysics Data System (ADS)

    Leinov, Eli; Lowe, Michael J. S.; Cawley, Peter

    2015-07-01

    Long-range guided wave testing is a well-established method for detection of corrosion defects in pipelines. The method is currently used routinely for above ground pipelines in a variety of industries, e.g. petrochemical and energy. When the method is applied to pipes buried in soil, test ranges tend to be significantly compromised and unpredictable due to attenuation of the guided wave resulting from energy leakage into the embedding soil. The attenuation characteristics of guided wave propagation in an 8 in. pipe buried in sand are investigated using a laboratory full-scale experimental rig and model predictions. We report measurements of attenuation of the T(0,1) and L(0,2) guided wave modes over a range of sand conditions, including loose, compacted, mechanically compacted, water saturated and drained. Attenuation values are found to be in the range of 1.65-5.5 dB/m and 0.98-3.2 dB/m for the torsional and longitudinal modes, respectively, over the frequency of 11-34 kHz. The application of overburden pressure modifies the compaction of the sand and increases the attenuation. Mechanical compaction of the sand yields similar attenuation values to those obtained with applied overburden pressure. The attenuation decreases in the fully water-saturated sand, and increases in drained sand to values comparable with those obtained for compacted sand. Attenuation measurements are compared with Disperse software model predictions and confirm that the attenuation phenomenon in buried pipes is essentially governed by the bulk shear velocity in the sand. The attenuation behaviour of the torsional guided wave mode is found not to be captured by a uniform soil model; comparison with predictions obtained with the Disperse software suggest that this is likely to be due to a layer of sand adhering to the surface of the pipe.

  2. Characteristics of SCC with Fly Ash and Manufactured Sand

    NASA Astrophysics Data System (ADS)

    Praveen Kumar, K.; Radhakrishna

    2016-09-01

    Self compacting concrete (SCC) of M40 grade was designed. The binder in SCC consists of OPC and fly ash in the ratio of 65:35. River sand was replaced by manufactured sand (M-sand) at replacement levels of 20,40,60,80 and 100%. An attempt was made to evaluate the workability and strength characteristics of self compacting concrete with river sand and manufactured sand as fine aggregates. For each replacement level, constant workability was maintained by varying the dosage of superplasticizer. T50 flow time, V Funnel time, V-funnel T5 time as well as compressive, split tensile and flexural strength of SCC were found at each replacement level of M-sand. They were compared to SCC with river sand. Results indicate favourable use of M-sand in preparation of Self Compacting Concrete.

  3. Science Learning in the Sand.

    ERIC Educational Resources Information Center

    Sexton, Ursula

    1997-01-01

    Presents activities that allow students to think about the Earth in a contextual manner and become familiar with constructive and destructive processes as they relate to sand - its origins, cyclical processes, and yielding of new products. Explores the bigger idea with a developmentally appropriate study of water, rocks, sand, physical phenomena,…

  4. Australian Red Dune Sand: A Potential Martian Regolith Analog

    NASA Technical Reports Server (NTRS)

    Kuhlman, K. R.; Marshall, J.; Evans, N. D.; Luttge, A.

    2001-01-01

    To demonstrate the potential scientific and technical merits of in situ microscopy on Mars, we analyzed a possible Martian regolith analog - an acolian red dune sand from the central Australian desert (near Mt. Olga). This sand was chosen for its ubiquitous red coating and the desert environment in which is it found. Grains of this sand were analyzed using a variety of microanalytical techniques. A database of detailed studies of such terrestrial analogs would assist the study of geological and astrobiological specimens in future missions to Mars. Potential instrument concepts for in situ deployment on Mars include local electrode atom probe nanoanalysis (LEAP), vertical scanning white light interferometry (VSWLI), scanning electron microscopies, energy dispersive x-ray microanalysis (EDX), atomic force microscopy (AFM) and X-ray diffraction (XRD). While in situ deployment of these techniques is many years away, ground-based studies using these analytical techniques extend our understanding of the data obtained from instruments to be flown in the near future.

  5. Advanced Techniques for Simulating the Behavior of Sand

    NASA Astrophysics Data System (ADS)

    Clothier, M.; Bailey, M.

    2009-12-01

    Computer graphics and visualization techniques continue to provide untapped research opportunities, particularly when working with earth science disciplines. Through collaboration with the Oregon Space Grant and IGERT Ecosystem Informatics programs we are developing new techniques for simulating sand. In addition, through collaboration with the Oregon Space Grant, we’ve been communicating with the Jet Propulsion Laboratory (JPL) to exchange ideas and gain feedback on our work. More specifically, JPL’s DARTS Laboratory specializes in planetary vehicle simulation, such as the Mars rovers. This simulation utilizes a virtual "sand box" to test how planetary rovers respond to different terrains while traversing them. Unfortunately, this simulation is unable to fully mimic the harsh, sandy environments of those found on Mars. Ideally, these simulations should allow a rover to interact with the sand beneath it, particularly for different sand granularities and densities. In particular, there may be situations where a rover may become stuck in sand due to lack of friction between the sand and wheels. In fact, in May 2009, the Spirit rover became stuck in the Martian sand and has provided additional motivation for this research. In order to develop a new sand simulation model, high performance computing will play a very important role in this work. More specifically, graphics processing units (GPUs) are useful due to their ability to run general purpose algorithms and ability to perform massively parallel computations. In prior research, simulating vast quantities of sand has been difficult to compute in real-time due to the computational complexity of many colliding particles. With the use of GPUs however, each particle collision will be parallelized, allowing for a dramatic performance increase. In addition, spatial partitioning will also provide a speed boost as this will help limit the number of particle collision calculations. However, since the goal of this

  6. 40 CFR 60.101 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... crude oil removed from the earth and the oils derived from tar sands, shale, and coal. (c) Process gas..., or react with a contact material suspended in a fluidized bed to improve feedstock quality for...

  7. Effects of Full-Scale Beach Renovation on Fecal Indicator Levels in Shoreline Sand and Water

    PubMed Central

    Hernandez, Rafael J.; Hernandez, Yasiel; Jimenez, Nasly H.; Piggot, Alan M.; Klaus, James S.; Feng, Zhixuan; Reniers, Ad; Solo-Gabriele, Helena M.

    2013-01-01

    Recolonization of enterococci, at a non-point source beach known to contain high background levels of bacteria, was studied after a full-scale beach renovation project. The renovation involved importation of new exogenous sand, in addition to infrastructure improvements. The study's objectives were to document changes in sand and water quality and to evaluate the relative contribution of different renovation activities towards these changes. These objectives were addressed: by measuring enterococci levels in the sand and fecal indicator bacteria levels (enterococci and fecal coliform) in the water, by documenting sediment characteristics (mineralogy and biofilm levels), and by estimating changes in observable enterococci loads. Analysis of enterococci levels on surface sand and within sediment depth cores were significantly higher prior to beach renovation (6.3 to 72 CFU/g for each sampling day) when compared to levels during and after beach renovation (0.8 CFU/g to 12 CFU/g) (p<0.01). During the renovation process, sand enterococci levels were frequently below detection limits (<0.1 CFU/g). For water, exceedances in the regulatory thresholds that would trigger a beach advisory decreased by 40% for enterococci and by 90% for fecal coliform. Factors that did not change significantly between pre- and post- renovation included the enterococci loads from animals (approx. 3 × 1011 CFU per month). Factors that were observed to change between pre- and post- renovation activities included: the composition of the beach sand (64% versus 98% quartz, and a significant decrease in biofilm levels) and loads from direct stormwater inputs (reduction of 3 × 1011 CFU per month). Overall, this study supports that beach renovation activities contributed to improved sand and water quality resulting in a 50% decrease of observable enterococci loads due to upgrades to the stormwater infrastructure. Of interest was that the change in the sand mineralogy also coincided with changes in

  8. Effects of full-scale beach renovation on fecal indicator levels in shoreline sand and water.

    PubMed

    Hernandez, Rafael J; Hernandez, Yasiel; Jimenez, Nasly H; Piggot, Alan M; Klaus, James S; Feng, Zhixuan; Reniers, Ad; Solo-Gabriele, Helena M

    2014-01-01

    Recolonization of enterococci, at a non-point source beach known to contain high background levels of bacteria, was studied after a full-scale beach renovation project. The renovation involved importation of new exogenous sand, in addition to infrastructure improvements. The study's objectives were to document changes in sand and water quality and to evaluate the relative contribution of different renovation activities towards these changes. These objectives were addressed: by measuring enterococci levels in the sand and fecal indicator bacteria levels (enterococci and fecal coliform) in the water, by documenting sediment characteristics (mineralogy and biofilm levels), and by estimating changes in observable enterococci loads. Analysis of enterococci levels on surface sand and within sediment depth cores were significantly higher prior to beach renovation (6.3-72 CFU/g for each sampling day) when compared to levels during and after beach renovation (0.8-12 CFU/g) (P < 0.01). During the renovation process, sand enterococci levels were frequently below detection limits (<0.1 CFU/g). For water, exceedances in the regulatory thresholds that would trigger a beach advisory decreased by 40% for enterococci and by 90% for fecal coliform. Factors that did not change significantly between pre- and post- renovation included the enterococci loads from animals (approx. 3 × 10(11) CFU per month). Factors that were observed to change between pre- and post- renovation activities included: the composition of the beach sand (64% versus 98% quartz, and a significant decrease in biofilm levels) and loads from direct stormwater inputs (reduction of 3 × 10(11) CFU per month). Overall, this study supports that beach renovation activities contributed to improved sand and water quality resulting in a 50% decrease of observable enterococci loads due to upgrades to the stormwater infrastructure. Of interest was that the change in the sand mineralogy also coincided with changes in biofilm

  9. Effects of sand fences on coastal dune vegetation distribution

    NASA Astrophysics Data System (ADS)

    Grafals-Soto, Rosana

    2012-04-01

    Sand fences are important human adjustments modifying the morphology of developed shores. The effects of sand fences on sediment transport and deposition in their initial stages have been well studied, but little is known about the effect of deteriorated sand fences that have become partially buried low scale barriers within the dune, potentially benefiting vegetation growth by protecting it from onshore stress. Data on vegetation, topography and fence characteristics were gathered at three dune sites in Ocean City, New Jersey on September 2007 and March 2008 to evaluate the effect of fences within the dune on vegetation distribution. Variables include: distance landward of dune toe, degree of sheltering from onshore stressors, net change in surface elevation (deposition or erosion), vegetation diversity and density, presence of remnant fence, and distance landward of fence. Results for the studied environment reveal that 1) vegetation diversity or density does not increase near remnant fences because most remnants are lower than average vegetation height and can not provide shelter; but 2) vegetation distribution is related to topographic variables, such as degree of sheltering, that are most likely the result of sand accretion caused by fence deployment. Fence deployment that prioritizes the creation of topographically diverse dunes within a restricted space may increase the diversity and density of the vegetation, and the resilience and value of developed dunes. Managers should consider the benefits of using sand fences on appropriately wide beaches to create a protective dune that is also diverse, functional and better able to adapt to change.

  10. Behavior of plastic sand confinement grids

    DOT National Transportation Integrated Search

    1986-01-01

    The concept of improving the load carrying ability of unbound aggregates, particularly sand, by lateral confinement has been investigated for some time. Extensive full-scale testing of the trafficability of confined beach sand pavement layers has bee...

  11. Efficient management of marine resources in conflict: an empirical study of marine sand mining, Korea.

    PubMed

    Kim, Tae-Goun

    2009-10-01

    This article develops a dynamic model of efficient use of exhaustible marine sand resources in the context of marine mining externalities. The classical Hotelling extraction model is applied to sand mining in Ongjin, Korea and extended to include the estimated marginal external costs that mining imposes on marine fisheries. The socially efficient sand extraction plan is compared with the extraction paths suggested by scientific research. If marginal environmental costs are correctly estimated, the developed efficient extraction plan considering the resource rent may increase the social welfare and reduce the conflicts among the marine sand resource users. The empirical results are interpreted with an emphasis on guidelines for coastal resource management policy.

  12. The physics of wind-blown sand and dust

    NASA Astrophysics Data System (ADS)

    Kok, Jasper F.; Parteli, Eric J. R.; Michaels, Timothy I.; Karam, Diana Bou

    2012-10-01

    The transport of sand and dust by wind is a potent erosional force, creates sand dunes and ripples, and loads the atmosphere with suspended dust aerosols. This paper presents an extensive review of the physics of wind-blown sand and dust on Earth and Mars. Specifically, we review the physics of aeolian saltation, the formation and development of sand dunes and ripples, the physics of dust aerosol emission, the weather phenomena that trigger dust storms, and the lifting of dust by dust devils and other small-scale vortices. We also discuss the physics of wind-blown sand and dune formation on Venus and Titan.

  13. The physics of wind-blown sand and dust.

    PubMed

    Kok, Jasper F; Parteli, Eric J R; Michaels, Timothy I; Karam, Diana Bou

    2012-10-01

    The transport of sand and dust by wind is a potent erosional force, creates sand dunes and ripples, and loads the atmosphere with suspended dust aerosols. This paper presents an extensive review of the physics of wind-blown sand and dust on Earth and Mars. Specifically, we review the physics of aeolian saltation, the formation and development of sand dunes and ripples, the physics of dust aerosol emission, the weather phenomena that trigger dust storms, and the lifting of dust by dust devils and other small-scale vortices. We also discuss the physics of wind-blown sand and dune formation on Venus and Titan.

  14. Gas emissions, minerals, and tars associated with three coal fires, Powder River Basin, USA.

    PubMed

    Engle, Mark A; Radke, Lawrence F; Heffern, Edward L; O'Keefe, Jennifer M K; Hower, James C; Smeltzer, Charles D; Hower, Judith M; Olea, Ricardo A; Eatwell, Robert J; Blake, Donald R; Emsbo-Mattingly, Stephen D; Stout, Scott A; Queen, Gerald; Aggen, Kerry L; Kolker, Allan; Prakash, Anupma; Henke, Kevin R; Stracher, Glenn B; Schroeder, Paul A; Román-Colón, Yomayra; ter Schure, Arnout

    2012-03-15

    Ground-based surveys of three coal fires and airborne surveys of two of the fires were conducted near Sheridan, Wyoming. The fires occur in natural outcrops and in abandoned mines, all containing Paleocene-age subbituminous coals. Diffuse (carbon dioxide (CO(2)) only) and vent (CO(2), carbon monoxide (CO), methane, hydrogen sulfide (H(2)S), and elemental mercury) emission estimates were made for each of the fires. Additionally, gas samples were collected for volatile organic compound (VOC) analysis and showed a large range in variation between vents. The fires produce locally dangerous levels of CO, CO(2), H(2)S, and benzene, among other gases. At one fire in an abandoned coal mine, trends in gas and tar composition followed a change in topography. Total CO(2) fluxes for the fires from airborne, ground-based, and rate of fire advancement estimates ranged from 0.9 to 780mg/s/m(2) and are comparable to other coal fires worldwide. Samples of tar and coal-fire minerals collected from the mouth of vents provided insight into the behavior and formation of the coal fires. Published by Elsevier B.V.

  15. Pore space analysis of NAPL distribution in sand-clay media

    USGS Publications Warehouse

    Matmon, D.; Hayden, N.J.

    2003-01-01

    This paper introduces a conceptual model of clays and non-aqueous phase liquids (NAPLs) at the pore scale that has been developed from a mathematical unit cell model, and direct micromodel observation and measurement of clay-containing porous media. The mathematical model uses a unit cell concept with uniform spherical grains for simulating the sand in the sand-clay matrix (???10% clay). Micromodels made with glass slides and including different clay-containing porous media were used to investigate the two clays (kaolinite and montmorillonite) and NAPL distribution within the pore space. The results were used to understand the distribution of NAPL advancing into initially saturated sand and sand-clay media, and provided a detailed analysis of the pore-scale geometry, pore size distribution, NAPL entry pressures, and the effect of clay on this geometry. Interesting NAPL saturation profiles were observed as a result of the complexity of the pore space geometry with the different packing angles and the presence of clays. The unit cell approach has applications for enhancing the mechanistic understanding and conceptualization, both visually and mathematically, of pore-scale processes such as NAPL and clay distribution. ?? 2003 Elsevier Science Ltd. All rights reserved.

  16. Investigation of guided waves propagation in pipe buried in sand

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Leinov, Eli; Cawley, Peter; Lowe, Michael J.S.

    The inspection of pipelines by guided wave testing is a well-established method for the detection of corrosion defects in pipelines, and is currently used routinely in a variety of industries, e.g. petrochemical and energy. When the method is applied to pipes buried in soil, test ranges tend to be significantly compromised because of attenuation of the waves caused by energy radiating into the soil. Moreover, the variability of soil conditions dictates different attenuation characteristics, which in-turn results in different, unpredictable, test ranges. We investigate experimentally the propagation and attenuation characteristics of guided waves in pipes buried in fine sand usingmore » a well characterized full scale experimental apparatus. The apparatus consists of an 8 inch-diameter, 5.6-meters long steel pipe embedded over 3 meters of its length in a rectangular container filled with fine sand, and an air-bladder for the application of overburden pressure. Longitudinal and torsional guided waves are excited in the pipe and recorded using a transducer ring (Guided Ultrasonics Ltd). Acoustic properties of the sand are measured independently in-situ and used to make model predictions of wave behavior in the buried pipe. We present the methodology and the systematic measurements of the guided waves under a range of conditions, including loose and compacted sand. It is found that the application of overburden pressure modifies the compaction of the sand and increases the attenuation, and that the measurement of the acoustic properties of sand allows model prediction of the attenuation of guided waves in buried pipes with a high level of confidence.« less

  17. Sand Dunes with Frost

    NASA Technical Reports Server (NTRS)

    2004-01-01

    9 May 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a suite of frost-covered sand dunes in the north polar region of Mars in early spring, 2004. The dunes indicate wind transport of sand from left to right (west to east). These landforms are located near 78.1oN, 220.8oW. This picture is illuminated by sunlight from the lower left and covers an area about 3 km (1.9 mi) across.

  18. Relationships Between Sand and Water Quality at Recreational Beaches

    PubMed Central

    Phillips, Matthew C.; Solo-Gabriele, Helena M.; Piggot, Alan M.; Klaus, James S.; Zhang, Yifan

    2011-01-01

    Enterococci are used to assess the risk of negative human health impacts from recreational waters. Studies have shown sustained populations of enterococci within sediments of beaches but comprehensive surveys of multiple tidal zones on beaches in a regional area and their relationship to beach management decisions are limited. We sampled three tidal zones on eight South Florida beaches in Miami-Dade and Broward counties and found that enterococci were ubiquitous within South Florida beach sands although their levels varied greatly both among the beaches and between the supratidal, intertidal and subtidal zones. The supratidal sands consistently had significantly higher (p<0.003) levels of enterococci (average 40 CFU/g dry sand) than the other two zones. Levels of enterococci within the subtidal sand correlated with the average level of enterococci in the water (CFU/100mL) for the season during which samples were collected (rs= 0.73). The average sand enterococci content over all the zones on each beach correlated with the average water enterococci levels of the year prior to sand samplings (rs=0.64) as well as the average water enterococci levels for the month after sand samplings (rs=0.54). Results indicate a connection between levels of enterococci in beach water and sands throughout South Florida’s beaches and suggest that the sands are one of the predominant reservoirs of enterococci impacting beach water quality. As a result, beaches with lower levels of enterococci in the sand had fewer exceedences relative to beaches with higher levels of sand enterococci. More research should focus on evaluating beach sand quality as a means to predict and regulate marine recreational water quality. PMID:22071324

  19. White Sands, Carrizozo Lava Beds, NM

    NASA Image and Video Library

    1982-03-30

    STS003-10-613 (22-30 March 1982) --- A truly remarkable view of White Sands and the nearby Carrizozo Lava Beds in southeast NM (33.5N, 106.5W). White Sands, site of the WW II atomic bomb development and testing facility and later post war nuclear weapons testing that can still be seen in the cleared circular patterns on the ground. Space shuttle Columbia (STS-3), this mission, landed at the White Sands alternate landing site because of bad weather at Edwards AFB, CA. Photo credit: NASA

  20. Mineralogy of Eolian Sands at Gale Crater

    NASA Technical Reports Server (NTRS)

    Achilles, C. N.; Vaniman, D. T.; Blake, D. F.; Bristow, T. F.; Rampe, E. B.; Ming, D. W.; Chipera, S. J.; Morris, R. V.; Morrison, S. M.; Downs, R. T.; hide

    2016-01-01

    The Mars Science Laboratory rover Curiosity has been exploring outcrop and regolith in Gale crater since August 6, 2012. During this exploration, the mission has collected 10 samples for mineralogical analysis by X-ray diffraction (XRD), using the CheMin instrument. The CheMin (Chemistry and Mineralogy) instrument on the Mars Science Laboratory rover Curiosity uses a CCD detector and a Co-anode tube source to acquire both mineralogy (from the pat-tern of Co diffraction) and chemical information (from energies of fluoresced X-rays). A detailed description of CheMin is provided in [1]. As part of the rover checkout after landing, the first sample selected for analysis was an eolian sand deposit (the Rocknest "sand shadow"). This sample was selected in part to characterize unconsolidated eolian regolith, but primarily to prove performance of the scoop collection system on the rover. The focus of the mission after Rocknest was on the consolidated sediments of Gale crater, so all of the nine subsequent samples were collected by drilling into bedrock com-posed of lithified sedimentary materials, including mudstone and sandstone. No scoop samples have been collected since Rocknest, but at the time this abstract was written the mission stands poised to use the scoop again, to collect active dune sands from the Bagnold dune field. Several abstracts at this conference outline the Bagnold dune campaign and summarize preliminary results from analyses on approach to the Namib dune sampling site. In this abstract we review the mineralogy of Rocknest, contrast that with the mineralogy of local sediments, and anticipate what will be learned by XRD analysis of Bagnold dune sands.

  1. Environmental consequences of oil production from oil sands

    NASA Astrophysics Data System (ADS)

    Rosa, Lorenzo; Davis, Kyle F.; Rulli, Maria C.; D'Odorico, Paolo

    2017-02-01

    Crude oil from oil sands will constitute a substantial share of future global oil demand. Oil sands deposits account for a third of globally proven oil reserves, underlie large natural forested areas, and have extraction methods requiring large volumes of freshwater. Yet little work has been done to quantify some of the main environmental impacts of oil sands operations. Here we examine forest loss and water use for the world's major oil sands deposits. We calculate actual and potential rates of water use and forest loss both in Canadian deposits, where oil sands extraction is already taking place, and in other major deposits worldwide. We estimated that their exploitation, given projected production trends, could result in 1.31 km3 yr-1 of freshwater demand and 8700 km2 of forest loss. The expected escalation in oil sands extraction thus portends extensive environmental impacts.

  2. A Minimal Chimera of Human Cyclin T1 and Tat Binds TAR and Activates Human Immunodeficiency Virus Transcription in Murine Cells

    PubMed Central

    Fujinaga, Koh; Irwin, Dan; Taube, Ran; Zhang, Fan; Geyer, Matthias; Peterlin, B. Matija

    2002-01-01

    The transcriptional elongation of human immunodeficiency virus type 1 (HIV-1) is mediated by the virally encoded transactivator Tat and its cellular cofactor, positive transcription elongation factor b (P-TEFb). The human cyclin T1 (hCycT1) subunit of P-TEFb forms a stable complex with Tat and the transactivation response element (TAR) RNA located at the 5′ end of all viral transcripts. Previous studies have demonstrated that hCycT1 binds Tat in a Zn2+-dependent manner via the cysteine at position 261, which is a tyrosine in murine cyclin T1. In the present study, we mutated all other cysteines and histidines that could be involved in this Zn2+-dependent interaction. Because all of these mutant proteins except hCycT1(C261Y) activated viral transcription in murine cells, no other cysteine or histidine in hCycT1 is responsible for this interaction. Next, we fused the N-terminal 280 residues in hCycT1 with Tat. Not only the full-length chimera but also the mutant hCycT1 with an N-terminal deletion to position 249, which retained the Tat-TAR recognition motif, activated HIV-1 transcription in murine cells. This minimal hybrid mutant hCycT1-Tat protein bound TAR RNA as well as human and murine P-TEFb in vitro. We conclude that this minimal chimera not only reproduces the high-affinity binding among P-TEFb, Tat, and TAR but also will be invaluable for determining the three-dimensional structure of this RNA-protein complex. PMID:12438619

  3. Guide to preparing SAND reports. Revised

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Locke, T.K.

    1996-04-01

    This guide contains basic information needed to produce a SAND report. Its guidelines reflect DOE regulation and Sandia policy. The guide includes basic writing instructions in an annotated sample report; guidance for organization, format, and layout of reports produced by line organizations; and information about conference papers, journal articles, and brochures. The appendixes contain sections on Sandia`s preferred usage, equations, references, copyrights and permissions, and publishing terms.

  4. Sand and Dust on Mars

    NASA Technical Reports Server (NTRS)

    Greeley, Ronald; Haberle, Robert M.

    1991-01-01

    Mars is a planet of high scientific interest. Various studies are currently being made that involve vehicles that have landed on Mars. Because Mars is known to experience frequent wind storms, mission planners and engineers require knowledge of the physical and chemical properties of Martian windblown sand and dust, and the processes involved in the origin and evolution of sand and dust storms.

  5. Hydrate morphology: Physical properties of sands with patchy hydrate saturation

    USGS Publications Warehouse

    Dai, S.; Santamarina, J.C.; Waite, William F.; Kneafsey, T.J.

    2012-01-01

    The physical properties of gas hydrate-bearing sediments depend on the volume fraction and spatial distribution of the hydrate phase. The host sediment grain size and the state of effective stress determine the hydrate morphology in sediments; this information can be used to significantly constrain estimates of the physical properties of hydrate-bearing sediments, including the coarse-grained sands subjected to high effective stress that are of interest as potential energy resources. Reported data and physical analyses suggest hydrate-bearing sands contain a heterogeneous, patchy hydrate distribution, whereby zones with 100% pore-space hydrate saturation are embedded in hydrate-free sand. Accounting for patchy rather than homogeneous hydrate distribution yields more tightly constrained estimates of physical properties in hydrate-bearing sands and captures observed physical-property dependencies on hydrate saturation. For example, numerical modeling results of sands with patchy saturation agree with experimental observation, showing a transition in stiffness starting near the series bound at low hydrate saturations but moving toward the parallel bound at high hydrate saturations. The hydrate-patch size itself impacts the physical properties of hydrate-bearing sediments; for example, at constant hydrate saturation, we find that conductivity (electrical, hydraulic and thermal) increases as the number of hydrate-saturated patches increases. This increase reflects the larger number of conductive flow paths that exist in specimens with many small hydrate-saturated patches in comparison to specimens in which a few large hydrate saturated patches can block flow over a significant cross-section of the specimen.

  6. Laboratory simulation studies of steady-state and potential catalytic effects in the ROPE{trademark} process

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Guffey, F.D.; Holper, P.A.

    The Western Research Institute is currently developing a process for the recovery of distillable liquid products from alternate fossil fuel sources such as tar sand and oil shale. The processing concept is based on recycling a fraction of the produced oil back into the reactor with the raw resource. This concept is termed the recycle oil pyrolysis and extraction (ROPE{sup TM}) process. The conversion of the alternate resource to a liquid fuel is performed in two stages. The first recovery stage is performed at moderate temperatures (325--420{degrees}C [617--788{degrees}F]) in the presence of product oil recycle. The second stage is performedmore » at higher temperatures (450--540{degrees}C [842--1004{degrees}F]) in the absence of product oil. The experiments reported here were performed Asphalt Ridge tar sand in the all-glass laboratory simulation reactor to simulate (1) the recycling of SAE 50 weight oil in the recycle oil pyrolysis zone and (2) to evaluate the potential catalytic effects of the sand matrix.« less

  7. Laboratory simulation studies of steady-state and potential catalytic effects in the ROPE trademark process

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Guffey, F.D.; Holper, P.A.

    The Western Research Institute is currently developing a process for the recovery of distillable liquid products from alternate fossil fuel sources such as tar sand and oil shale. The processing concept is based on recycling a fraction of the produced oil back into the reactor with the raw resource. This concept is termed the recycle oil pyrolysis and extraction (ROPE{sup TM}) process. The conversion of the alternate resource to a liquid fuel is performed in two stages. The first recovery stage is performed at moderate temperatures (325--420{degrees}C (617--788{degrees}F)) in the presence of product oil recycle. The second stage is performedmore » at higher temperatures (450--540{degrees}C (842--1004{degrees}F)) in the absence of product oil. The experiments reported here were performed Asphalt Ridge tar sand in the all-glass laboratory simulation reactor to simulate (1) the recycling of SAE 50 weight oil in the recycle oil pyrolysis zone and (2) to evaluate the potential catalytic effects of the sand matrix.« less

  8. PAH concentrations in lake sediment decline following ban on coal-tar-based pavement sealants in Austin, Texas

    USGS Publications Warehouse

    Van Metre, Peter C.; Mahler, Barbara J.

    2013-01-01

    Recent studies have concluded that coal-tar-based pavement sealants are a major source of polycyclic aromatic hydrocarbons (PAHs) in urban settings in large parts of the United States. In 2006, Austin, TX, became the first jurisdiction in the U.S. to ban the use of coal-tar sealants. We evaluated the effect of Austin’s ban by analyzing PAHs in sediment cores and bottom-sediment samples collected in 1998, 2000, 2001, 2012, and 2014 from Lady Bird Lake, the principal receiving water body for Austin urban runoff. The sum concentration of the 16 EPA Priority Pollutant PAHs (∑PAH16) in dated core intervals and surficial bottom-sediment samples collected from sites in the lower lake declined about 44% from 1998–2005 to 2006–2014 (means of 7980 and 4500 μg kg–1, respectively), and by 2012–2014, the decline was about 58% (mean of 3320 μg kg–1). Concentrations of ∑PAH16 in bottom sediment from two of three mid-lake sites decreased by about 71 and 35% from 2001 to 2014. Concentrations at a third site increased by about 14% from 2001 to 2014. The decreases since 2006 reverse a 40-year (1959–1998) upward trend. Despite declines in PAH concentrations, PAH profiles and source-receptor modeling results indicate that coal-tar sealants remain the largest PAH source to the lake, implying that PAH concentrations likely will continue to decline as stocks of previously applied sealant gradually become depleted.

  9. Transport of colloidal silica in unsaturated sand: Effect of charging properties of sand and silica particles.

    PubMed

    Fujita, Yosuke; Kobayashi, Motoyoshi

    2016-07-01

    We have studied the transport of colloidal silica in various degrees of a water-saturated Toyoura sand column, because silica particles are widely used as catalyst carriers and abrasive agents, and their toxicity is reported recently. Since water-silica, water-sand, and air-water interfaces have pH-dependent negative charges, the magnitude of surface charge was controlled by changing the solution pH. The results show that, at high pH conditions (pH 7.4), the deposition of colloidal silica to the sand surface is interrupted and the silica concentration at the column outlet immediately reaches the input concentration in saturated conditions. In addition, the relative concentration of silica at the column outlet only slightly decreases to 0.9 with decreasing degrees of water saturation to 38%, because silica particles are trapped in straining regions in the soil pore and air-water interface. On the other hand, at pH 5 conditions (low pH), where sand and colloid have less charge, reduced repulsive forces result in colloidal silica attaching onto the sand in saturated conditions. The deposition amount of silica particles remarkably increases with decreasing degrees of water saturation to 37%, which is explained by more particles being retained in the sand column associated with the air-water interface. In conclusion, at higher pH, the mobility of silica particles is high, and the air-water interface is inactive for the deposition of silica. On the other hand, at low pH, the deposition amount increases with decreasing water saturation, and the particle transport is inhibited. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Relationships between sand and water quality at recreational beaches.

    PubMed

    Phillips, Matthew C; Solo-Gabriele, Helena M; Piggot, Alan M; Klaus, James S; Zhang, Yifan

    2011-12-15

    Enterococci are used to assess the risk of negative human health impacts from recreational waters. Studies have shown sustained populations of enterococci within sediments of beaches but comprehensive surveys of multiple tidal zones on beaches in a regional area and their relationship to beach management decisions are limited. We sampled three tidal zones on eight South Florida beaches in Miami-Dade and Broward counties and found that enterococci were ubiquitous within South Florida beach sands although their levels varied greatly both among the beaches and between the supratidal, intertidal and subtidal zones. The supratidal sands consistently had significantly higher (p < 0.003) levels of enterococci (average 40 CFU/g dry sand) than the other two zones. Levels of enterococci within the subtidal sand correlated with the average level of enterococci in the water (CFU/100mL) for the season during which samples were collected (r(s) = 0.73). The average sand enterococci content over all the zones on each beach correlated with the average water enterococci levels of the year prior to sand samplings (r(s) = 0.64) as well as the average water enterococci levels for the month after sand samplings (r(s) = 0.54). Results indicate a connection between levels of enterococci in beach water and sands throughout South Florida's beaches and suggest that the sands are one of the predominant reservoirs of enterococci impacting beach water quality. As a result, beaches with lower levels of enterococci in the sand had fewer exceedences relative to beaches with higher levels of sand enterococci. More research should focus on evaluating beach sand quality as a means to predict and regulate marine recreational water quality. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Mechanics and energetics of human locomotion on sand.

    PubMed

    Lejeune, T M; Willems, P A; Heglund, N C

    1998-07-01

    Moving about in nature often involves walking or running on a soft yielding substratum such as sand, which has a profound effect on the mechanics and energetics of locomotion. Force platform and cinematographic analyses were used to determine the mechanical work performed by human subjects during walking and running on sand and on a hard surface. Oxygen consumption was used to determine the energetic cost of walking and running under the same conditions. Walking on sand requires 1.6-2.5 times more mechanical work than does walking on a hard surface at the same speed. In contrast, running on sand requires only 1.15 times more mechanical work than does running on a hard surface at the same speed. Walking on sand requires 2.1-2.7 times more energy expenditure than does walking on a hard surface at the same speed; while running on sand requires 1.6 times more energy expenditure than does running on a hard surface. The increase in energy cost is due primarily to two effects: the mechanical work done on the sand, and a decrease in the efficiency of positive work done by the muscles and tendons.

  12. Experimental Study of Sand Production and Mud Erosion Phenomena for Sand Mud Alternate Layer

    NASA Astrophysics Data System (ADS)

    Oyama, H.; Sato, T.

    2014-12-01

    Methane hydrates are crystalline, ice-like compounds under specific thermodynamic conditions. The existence of methane hydrates is confirmed in the Nankai Trough, an offshore area of Japan. Japan's Methane Hydrate Research and Development Program (MH21) has been under way at this area. In the early 2013, the world's first intentional gas production attempt from marine gas hydrate deposits was tried and accomplished in the Daini Atumi Knoll area of the Eastern Nankai Trough. For gas production, depressurization method has been considered as a promising gas production technique from methane hydrate reservoirs. However, considering of continuous gas production over a long period, there is still something to clarify. The methane hydrate crystals are very small and existed in the intergranular pores of sandy layer of turbidite sediments. When the intergranular methane hydrates will be dissociated, it is considered that dissociated gas and water flow will cause sand production and mud erosion phenomena of turbidite sediments. The production of framework sands into a well is one of the problems plaguing the gas because of its adverse effects on well productivity and equipment. If the eroded mud is accumulated in the pore space of sand, skin is generated and permeability becomes lower. In addition, mud erosion has a negative effect for the well stability. This research presents an experimental study to understand sand production and mud erosion phenomena for sand mud alternate layer. The aims of this study are to understand these phenomena and clarify driving forces. In our experiments, we used an artificial sedimentary core and performed experiments under various conditions. As the results, the driving forces of these phenomena are not dissociation gas flow but water flow through pore.

  13. Observations of transport of bacterial-like microspheres through beach sand

    NASA Astrophysics Data System (ADS)

    Gast, Rebecca J.; Elgar, Steve; Raubenheimer, Britt

    2015-04-01

    Often, there is an order of magnitude more fecal indicator bacteria (enterococci) in beach sand than in nearby water. Consequently, sand is considered a reservoir for these bacteria, potentially contributing to poor water quality, and raising questions regarding the human health risks associated with sand exposure. An integral aspect of the distribution and persistence of sand-associated enterococci is the transport of bacteria introduced into the beach environment. Here, plastic microspheres are used as a proxy to examine the wave-induced movement of bacterial-like particles through sand on an ocean beach. Laboratory tests suggest microspheres and bacteria move similarly through sand columns, and have qualitatively similar short-term adsorption-to-sand behavior. Microspheres buried ~0.05 m below the sand surface on an ocean beach moved rapidly [O(10-3) m/s] away from their initial location, both vertically into the ground water below the sand and horizontally seaward within the sediment matrix in response to waves running up the beach face and percolating through the sand.

  14. Geologic and paleoecologic studies of the Nebraska Sand Hills

    USGS Publications Warehouse

    Ahlbrandt, Thomas S.; Fryberger, S.G.; Hanley, John H.; Bradbury, J. Platt

    1980-01-01

    PART A: The Nebraska Sand Hills are an inactive, late Quaternary, most probably Holocene, dune field (covering 57,000 km 2 ) that have been eroded along streams and in blowouts, resulting in excellent lateral and vertical exposures of the stratification of dune and interdune sediments. This paper presents new data on the geometry, primary sedimentary structures, modification of sedimentary structures, direction of sand movement, and petrography of these eolian deposits. Eolian deposits of the Sand Hills occur as relatively thin (9-24 m) 'blanket' sands, composed of a complex of dune and discontinuous, diachronous interdune deposits unconformably overlying fluviolacustrine sediments. The internal stratification of large dunes in the Sand Hills (as high as 100 m), is similar to the internal stratification of smaller dunes of the same type in the Sand Hills, differing only in scale. Studies of laminae orientation in the Sand Hills indicate that transverse, barchan, and blowout dunes can be differentiated in rocks of eolian origin using both the mean dip angle of laminae and the mean angular deviation of dip direction. A variety of secondary structures modify or replace primary eolian stratification in the Sand Hills, the more common of which are dissipation structures and bioturbation. Dissipation structures in the Sand Hills may develop when infiltrating water deposits clay adjacent to less permeable layers in the sand, or along the upper margins of frozen layers that form in the sands during winter. Cross-bed measurements from dunes of the Nebraska Sand Hills necessitate a new interpretation of the past sand transport directions. The data from these measurements indicate a general northwest-to-southeast drift of sand, with a more southerly drift in the southeast part of the Sand Hills. A large area of small dunes < 100 m high) described by Smith (1965) as linear or seif in the central part of the Sand Hills was interpreted by him on the basis of morphology only. We

  15. Bacteria in beach sands: an emerging challenge in protecting coastal water quality and bather health

    PubMed Central

    Gast, Rebecca J.

    2011-01-01

    To protect bather health at recreational beaches, fecal indicator bacterial standards are used to monitor water quality, and waters exceeding the standards are subsequently closed to bathers. However beachgoers are also in contact with beach sands, the sanitary quality of which is not included within beach monitoring programs. In fact, sands and sediments provide habitat where fecal bacterial populations may persist, and in some cases grow, in the coastal zone. Specific pathogens are less well studied in beach sands and sediments, but there is a body of evidence that they too may persist in these environments. This paper reviews the current state of knowledge regarding the abundance and distribution of fecal indicator bacteria and pathogens in beach sands of diverse climatological regions, and at beaches subjected to varied levels of anthropogenic impact. In all regions fecal indicator bacteria are nearly ubiquitous in beach sands, and similar relationships emerge between fecal indicator abundance in dry sand, submerged sands, and water. Taken together, these studies contextualize a potential public health issue and identify research questions that must be addressed in order to support future policy decisions. PMID:21162561

  16. Smoldering Remediation of Coal-Tar-Contaminated Soil: Pilot Field Tests of STAR.

    PubMed

    Scholes, Grant C; Gerhard, Jason I; Grant, Gavin P; Major, David W; Vidumsky, John E; Switzer, Christine; Torero, Jose L

    2015-12-15

    Self-sustaining treatment for active remediation (STAR) is an emerging, smoldering-based technology for nonaqueous-phase liquid (NAPL) remediation. This work presents the first in situ field evaluation of STAR. Pilot field tests were performed at 3.0 m (shallow test) and 7.9 m (deep test) below ground surface within distinct lithological units contaminated with coal tar at a former industrial facility. Self-sustained smoldering (i.e., after the in-well ignition heater was terminated) was demonstrated below the water table for the first time. The outward propagation of a NAPL smoldering front was mapped, and the NAPL destruction rate was quantified in real time. A total of 3700 kg of coal tar over 12 days in the shallow test and 860 kg over 11 days in the deep test was destroyed; less than 2% of total mass removed was volatilized. Self-sustaining propagation was relatively uniform radially outward in the deep test, achieving a radius of influence of 3.7 m; strong permeability contrasts and installed barriers influenced the front propagation geometry in the shallow test. Reductions in soil hydrocarbon concentrations of 99.3% and 97.3% were achieved in the shallow and deep tests, respectively. Overall, this provides the first field evaluation of STAR and demonstrates that it is effective in situ and under a variety of conditions and provides the information necessary for designing the full-scale site treatment.

  17. Improved Sand-Compaction Method for Lost-Foam Metal Casting

    NASA Technical Reports Server (NTRS)

    Bakhtiyarov, Sayavur I.; Overfelt, Ruel A.

    2008-01-01

    An improved method of filling a molding flask with sand and compacting the sand around a refractory-coated foam mold pattern has been developed for incorporation into the lost-foam metal-casting process. In comparison with the conventional method of sand filling and compaction, this method affords more nearly complete filling of the space around the refractory-coated foam mold pattern and more thorough compaction of the sand. In so doing, this method enables the sand to better support the refractory coat under metallostatic pressure during filling of the mold with molten metal.

  18. Effect of substrate size on sympatric sand darter benthic habitat preferences

    USGS Publications Warehouse

    Thompson, Patricia A.; Welsh, Stuart A.; Rizzo, Austin A.; Smith, Dustin M.

    2017-01-01

    The western sand darter, Ammocrypta clara, and the eastern sand darter, A. pellucida, are sand-dwelling fishes that have undergone range-wide population declines, presumably owing to habitat loss. Habitat use studies have been conducted for the eastern sand darter, but literature on the western sand darter remains sparse. To evaluate substrate selection and preference, western and eastern sand darters were collected from the Elk River, West Virginia, one of the few remaining rivers where both species occur sympatrically. In the laboratory, individuals were given the choice to bury into five equally available and randomly positioned substrates ranging from fine sand to granule gravel (0.12–4.0 mm). The western sand darter selected for coarse and medium sand, while the eastern sand darter was more of a generalist selecting for fine, medium, and coarse sand. Substrate selection was significantly different (p = 0.02) between species in the same environment, where the western sand darter preferred coarser substrate more often compared to the eastern sand darter. Habitat degradation is often a limiting factor for many species of rare freshwater fish, and results from this study suggest that western and eastern sand darters may respond differently to variations in benthic substrate composition.

  19. Windblown Sand in West Candor

    NASA Technical Reports Server (NTRS)

    2004-01-01

    23 December 2003

    West Candor Chasma, a part of the vast Valles Marineris trough system, is known for its layered sedimentary rock outcrops. It is less known for dark fields of windblown sand, but that is what occurs in the north-central part of the chasm. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image, obtained in December 2003, shows the interplay of dark, wind-blown sand with buttes and mesas of layered rock in west Candor Chasma. Dark streamers of sand point toward the east/southeast (right/lower right), indicating that dominant winds blow from the west. This picture is located near 5.2oS, 75.7oW, and covers an area 3 km (1.9 mi) wide. Sunlight illuminates the scene from the lower left.

  20. Aerolian erosion, transport, and deposition of volcaniclastic sands among the shifting sand dunes, Christmas Lake Valley, Oregon: TIMS image analysis

    NASA Technical Reports Server (NTRS)

    Edgett, Kenneth S.; Ramsey, Michael S.; Christensen, Philip R.

    1995-01-01

    Remote sensing is a tool that, in the context of aeolian studies, offers a synoptic view of a dune field, sand sea, or entire desert region. Blount et al. (1990) presented one of the first studies demonstrating the power of multispectral images for interpreting the dynamic history of an aeolian sand sea. Blount's work on the Gran Desierto of Mexico used a Landsat TM scene and a linear spectral mixing model to show where different sand populations occur and along what paths these sands may have traveled before becoming incorporated into dunes. Interpretation of sand transport paths and sources in the Gran Desierto led to an improved understanding of the origin and Holocene history of the dunes. With the anticipated advent of the EOS-A platform and ASTER thermal infrared capability in 1998, it will become possible to look at continental sand seas and map sand transport paths using 8-12 mu m bands that are well-suited to tracking silicate sediments. A logical extension of Blount's work is to attempt a similar study using thermal infrared images. One such study has already begun by looking at feldspar, quartz, magnetite, and clay distributions in the Kelso Dunes of southern California. This paper describes the geology and application of TIMS image analysis of a less-well known Holocene dune field in south central Oregon using TIMS data obtained in 1991.

  1. Juniper tar (cade oil) poisoning in new born after a cutaneous application

    PubMed Central

    Achour, Sanae; Abourazzak, Sana; Mokhtari, Abdelrhani; Soulaymani, Abdelmjid; Soulaymani, Rachida; Hida, Moustapha

    2011-01-01

    Juniper tar (cade oil) is distilled from the branches and wood of Juniperus oxycedrus. It contains etheric oils, triterpene and phenols, used for many purposes in folk medicine. The authors report a case of a previously healthy new born treated with a topical application of Juniperus oxycedrus for atopic dermatosis The poisoning caused convulsions, collapsus, acute pulmonary oedema, renal failure and hepatotoxicity. The newborn survived after supportive and symptomatic treatment, and discharged in a good condition on the eleventh day of hospitalisation in intensive care unit. PMID:22675090

  2. The provenance of Taklamakan desert sand

    NASA Astrophysics Data System (ADS)

    Rittner, Martin; Vermeesch, Pieter; Carter, Andrew; Bird, Anna; Stevens, Thomas; Garzanti, Eduardo; Andò, Sergio; Vezzoli, Giovanni; Dutt, Ripul; Xu, Zhiwei; Lu, Huayu

    2016-03-01

    Sand migration in the vast Taklamakan desert within the Tarim Basin (Xinjiang Uyghur Autonomous region, PR China) is governed by two competing transport agents: wind and water, which work in diametrically opposed directions. Net aeolian transport is from northeast to south, while fluvial transport occurs from the south to the north and then west to east at the northern rim, due to a gradual northward slope of the underlying topography. We here present the first comprehensive provenance study of Taklamakan desert sand with the aim to characterise the interplay of these two transport mechanisms and their roles in the formation of the sand sea, and to consider the potential of the Tarim Basin as a contributing source to the Chinese Loess Plateau (CLP). Our dataset comprises 39 aeolian and fluvial samples, which were characterised by detrital-zircon U-Pb geochronology, heavy-mineral, and bulk-petrography analyses. Although the inter-sample differences of all three datasets are subtle, a multivariate statistical analysis using multidimensional scaling (MDS) clearly shows that Tarim desert sand is most similar in composition to rivers draining the Kunlun Shan (south) and the Pamirs (west), and is distinctly different from sediment sources in the Tian Shan (north). A small set of samples from the Junggar Basin (north of the Tian Shan) yields different detrital compositions and age spectra than anywhere in the Tarim Basin, indicating that aeolian sediment exchange between the two basins is minimal. Although river transport dominates delivery of sand into the Tarim Basin, wind remobilises and reworks the sediment in the central sand sea. Characteristic signatures of main rivers can be traced from entrance into the basin to the terminus of the Tarim River, and those crossing the desert from the south to north can seasonally bypass sediment through the sand sea. Smaller ephemeral rivers from the Kunlun Shan end in the desert and discharge their sediment there. Both river run

  3. Sand dollar: a weight belt for the juvenile.

    PubMed

    Chia, F S

    1973-07-06

    Juvenile sand dollars (Dendraster excentricus) selectively ingest heavy sand grains from the substrate and store them in an intestinal diverticulum which may function as a weight belt, assisting the young animal to remain in the shifting sandy environment. The sand disappears from the diverticulum when the animal reaches the length of 30 millimeters.

  4. Where Do the Sand-Dust Storms Come From?: Conversations with Specialists from the Exploring Sand-Dust Storms Scientific Expedition Team

    ERIC Educational Resources Information Center

    Shixin, Liu

    2004-01-01

    This article relates the different views from specialists of the scientific expedition team for the exploration of the origin of sand-dust storms. They observed and examined on-site the ecological environment of places of origin for sand-dust storms, and tried to find out causes of sand-dust storm and what harm it can cause in the hope of…

  5. Concentrations of polycyclic aromatic hydrocarbons (PAHs) and azaarenes in runoff from coal-tar- and asphalt-sealcoated pavement

    USGS Publications Warehouse

    Mahler, Barbara J.; Van Metre, Peter C.; Foreman, William T.

    2014-01-01

    Coal-tar-based sealcoat, used extensively on parking lots and driveways in North America, is a potent source of PAHs. We investigated how concentrations and assemblages of PAHs and azaarenes in runoff from pavement newly sealed with coal-tar-based (CT) or asphalt-based (AS) sealcoat changed over time. Samples of simulated runoff were collected from pavement 5 h to 111 d following application of AS or CT sealcoat. Concentrations of the sum of 16 PAHs (median concentrations of 328 and 35 μg/L for CT and AS runoff, respectively) in runoff varied relatively little, but rapid decreases in concentrations of azaarenes and low molecular weight PAHs were offset by increases in high molecular weight PAHs. The results demonstrate that runoff from CT-sealcoated pavement, in particular, continues to contain elevated concentrations of PAHs long after a 24-h curing time, with implications for the fate, transport, and ecotoxicological effects of contaminants in runoff from CT-sealcoated pavement.

  6. Concentrations of polycyclic aromatic hydrocarbons (PAHs) and azaarenes in runoff from coal-tar- and asphalt-sealcoated pavement.

    PubMed

    Mahler, Barbara J; Van Metre, Peter C; Foreman, William T

    2014-05-01

    Coal-tar-based sealcoat, used extensively on parking lots and driveways in North America, is a potent source of PAHs. We investigated how concentrations and assemblages of PAHs and azaarenes in runoff from pavement newly sealed with coal-tar-based (CT) or asphalt-based (AS) sealcoat changed over time. Samples of simulated runoff were collected from pavement 5 h to 111 d following application of AS or CT sealcoat. Concentrations of the sum of 16 PAHs (median concentrations of 328 and 35 μg/L for CT and AS runoff, respectively) in runoff varied relatively little, but rapid decreases in concentrations of azaarenes and low molecular weight PAHs were offset by increases in high molecular weight PAHs. The results demonstrate that runoff from CT-sealcoated pavement, in particular, continues to contain elevated concentrations of PAHs long after a 24-h curing time, with implications for the fate, transport, and ecotoxicological effects of contaminants in runoff from CT-sealcoated pavement. Published by Elsevier Ltd.

  7. Mass Transfer Coefficientin Stirred Tank for p-Cresol Extraction Process from Coal Tar

    NASA Astrophysics Data System (ADS)

    Fardhyanti, D. S.; Tyaningsih, D. S.; Afifah, S. N.

    2017-04-01

    Indonesia is a country that has a lot of coal resources. The Indonesian coal has a low caloric value. Pyrolysis is one of the process to increase the caloric value. One of the by-product of the pyrolysis process is coal tar. It contains a lot of aliphatic or aromatic compounds such asp-cresol (11% v/v). It is widely used as a disinfectant. Extractionof p-Cresol increases the economic value of waste of coal. The aim of this research isto study about mass tranfer coefficient in the baffled stirred tank for p-Cresolextraction from coal tar. Mass transfer coefficient is useful for design and scale up of industrial equipment. Extraction is conducted inthe baffled stirred tank equipped with a four-bladed axial impeller placed vertically in the vessel. Sample for each time processing (5, 10, 15, 20, 25 and 30minutes) was poured into a separating funnel, settled for an hour and separated into two phases. Then the two phases were weighed. The extract phases and raffinate phases were analyzed by Spectronic UV-Vis. The result showed that mixing speed of p-Cresol extraction increasesthe yield of p-Cresol and the mass transfer coefficient. The highest yield of p-Cresol is 49.32% and the highest mass transfer coefficient is 4.757 x 10-6kg/m2s.

  8. List of Publications of the US Army Engineer Waterways Experiment Station. Volume 1.

    DTIC Science & Technology

    1986-12-01

    Leo R 3-06 Feb 1960 Factors Affectin6 Beach Nourishment Requirements, AD 631 520 Presque Isle Peninsula, Erie , Pennsylvania , by D. W. Berg H 4-66 Jun...962 Pressures TM 3-377 Jan 1954 Heat and Blast Effects on Tar and Tar-Rubber Pavements, AD 030 247 Presque Isle Air Force Base, Maine TM 3-379...G. Aubrev, and J. Karpen MR 80-10 Nov 1980 Sand Resources of Southern Lake Erie , Conneaut to AD A097 984 Toledo, Ohio - A Seismic Reflection and

  9. Potential of iron sand from Betaf beach, Sarmi regency and river sand from Doyo, Jayapura regency, Papua as basic materials of mortar as nuclear radiation shielding

    NASA Astrophysics Data System (ADS)

    Haryati, E.; Dahlan, K.

    2018-03-01

    According to the SNI, the type of concrete for use as nuclear radiation shielding is concrete or mortar that contains hematite, ilmenite, magnetite, barite, or ferrophosphorus synthesis. This study is focused on the characterization of iron sand from and river sand from Papua. The purpose of this research was to determine the specific content of gravity and minerals in iron sand and river sand from Papua. The specific gravities of the sands were measured by manual experiment in a laboratory, while their mineral content were calculated using XRF and SEM - EDS method. The result showed that the specific gravities of iron sand and river sand were 2.66 and 2.50, respectively. The XRF method revealed that the iron sand contained 41.68% Silica, 33.84% Iron, and 24.48% other minerals. The river sand on the other hand contained 58.98% Silica (Si), 26.87% Iron (Fe), and 14.15% other minerals. The SEM -EDS method showed that the iron sand was composed of 39.99 % SiO2, 21.67 % FeO, and, and 38.34 % others; while the river sand contained 39.28% SiO2, 17.45 % FeO, and 43.27 % others. The result showed that both sands have the potentials to be isolated from hematite minerals or magnetite.

  10. Three dimensional fabric evolution of sheared sand

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hasan, Alsidqi; Alshibli, Khalid

    2012-10-24

    Granular particles undergo translation and rolling when they are sheared. This paper presents a three-dimensional (3D) experimental assessment of fabric evolution of sheared sand at the particle level. F-75 Ottawa sand specimen was tested under an axisymmetric triaxial loading condition. It measured 9.5 mm in diameter and 20 mm in height. The quantitative evaluation was conducted by analyzing 3D high-resolution x-ray synchrotron micro-tomography images of the specimen at eight axial strain levels. The analyses included visualization of particle translation and rotation, and quantification of fabric orientation as shearing continued. Representative individual particles were successfully tracked and visualized to assess themore » mode of interaction between them. This paper discusses fabric evolution and compares the evolution of particles within and outside the shear band as shearing continues. Changes in particle orientation distributions are presented using fabric histograms and fabric tensor.« less

  11. Advanced characterisation of organic matter in oil sands and tailings sands used for land reclamation by Fourier transform-ion cyclotron resonance-mass spectrometry (FT-ICR-MS)

    NASA Astrophysics Data System (ADS)

    Noah, M.; Vieth-Hillebrand, A.; Wilkes, H.

    2012-04-01

    The Athabasca region of northern Alberta, Canada, is home to deposits of oil sands containing vast amounts (~ 173 billion barrels) of heavily biodegraded petroleum. Oil sands are recovered by surface mining or by in situ steam injection. The extraction of bitumen from oil sands by caustic hot water processing results in large volumes of fluid tailings, which are stored in on-site settling basins. There the tailings undergo a compaction and dewatering process, producing a slowly densifying suspension. The released water is recycled for extraction. The fine tailings will be reclaimed as either dry or wet landscapes. [1] To produce 1 barrel of crude oil, 2 tons of oil sand and 2 - 3 tons of water (including recycled water) are required. [2] Open pit mining and the extraction of the bitumen from the oil sands create large and intense disturbances of different landscapes. The area currently disturbed by mining operations covers about 530 km2 and the area of tailing ponds surpasses 130 km2. An issue of increasing importance is the land remediation and reclamation of oil sand areas in Canada and the reconstruction of these disturbed landscapes back to working ecosystems similar to those existing prior to mining operations. An important issue in this context is the identification of oil sand-derived organic compounds in the tailings, their environmental behaviour and the resulting chances and limitations with respect to land reclamation. Furthermore the biodegradation processes that occur in the tailings and that could lead to a decrease in hazardous organic compounds are important challenges, which need to be investigated. This presentation will give a detailed overview of our compositional and quantitative characterisation of the organic matter in oil sand, unprocessed and processed mature fine tailings samples as well as in tailings sands used as part of land reclamation. The analytical characterisation is based on the extraction of the soluble organic matter, its

  12. Dual leakoff beehavior in hydraulic fracturing of tight, lenticular gas sands

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Warpinski, N.R.

    Stimulation experiments conducted in anisotropic, naturally fractured, tight, lenticular, gas sandstones have shown the existence of a dual leakoff phenomenon. Below a threshold, leakoff increases by a factor of 50, slurries dehydrate rapidly, and screenouts occur in minutes. The leakoff has been shown to be controllable to some extent with 100-mesh sand. Results of three stimulation experiments are presented; three include a treatment that screened out, a minifrac experiment that showed the effectiveness of 100-mesh sand, and a final successful stimulation. 30 refs., 14 figs., 6 tabs.

  13. Augmenting Sand Simulation Environments through Subdivision and Particle Refinement

    NASA Astrophysics Data System (ADS)

    Clothier, M.; Bailey, M.

    2012-12-01

    Recent advances in computer graphics and parallel processing hardware have provided disciplines with new methods to evaluate and visualize data. These advances have proven useful for earth and planetary scientists as many researchers are using this hardware to process large amounts of data for analysis. As such, this has provided opportunities for collaboration between computer graphics and the earth sciences. Through collaboration with the Oregon Space Grant and IGERT Ecosystem Informatics programs, we are investigating techniques for simulating the behavior of sand. We are also collaborating with the Jet Propulsion Laboratory's (JPL) DARTS Lab to exchange ideas and gain feedback on our research. The DARTS Lab specializes in simulation of planetary vehicles, such as the Mars rovers. Their simulations utilize a virtual "sand box" to test how a planetary vehicle responds to different environments. Our research builds upon this idea to create a sand simulation framework so that planetary environments, such as the harsh, sandy regions on Mars, are more fully realized. More specifically, we are focusing our research on the interaction between a planetary vehicle, such as a rover, and the sand beneath it, providing further insight into its performance. Unfortunately, this can be a computationally complex problem, especially if trying to represent the enormous quantities of sand particles interacting with each other. However, through the use of high-performance computing, we have developed a technique to subdivide areas of actively participating sand regions across a large landscape. Similar to a Level of Detail (LOD) technique, we only subdivide regions of a landscape where sand particles are actively participating with another object. While the sand is within this subdivision window and moves closer to the surface of the interacting object, the sand region subdivides into smaller regions until individual sand particles are left at the surface. As an example, let's say

  14. Unloading Characteristics of Sand-drift in Wind-shallow Areas along Railway and the Effect of Sand Removal by Force of Wind

    PubMed Central

    Cheng, Jian-jun; Xin, Guo-Wei; Zhi, Ling-yan; Jiang, Fu-qiang

    2017-01-01

    Wind-shield walls decrease the velocity of wind-drift sand flow in transit. This results in sand accumulating in the wind-shadow zone of both windshield wall and track line, causing severe sand sediment hazard. This study reveals the characteristics of sand accumulation and the laws of wind-blown sand removal in the wind-shadow areas of three different types of windshield walls, utilizing three-dimensional numerical simulations and wind tunnel experiments and on-site sand sediment tests. The results revealed the formation of apparent vortex and acceleration zones on the leeward side of solid windshield walls. For uniform openings, the vortex area moved back and narrowed. When bottom-opening windshield walls were adopted, the track-supporting layer at the step became a conflux acceleration zone, forming a low velocity vortex zone near the track line. At high wind speeds, windshield walls with bottom-openings achieved improved sand dredging. Considering hydrodynamic mechanisms, the flow field structure on the leeward side of different types of windshield structures is a result of convergence and diffusion of fluids caused by an obstacle. This convergence and diffusion effect of air fluid is more apparent at high wind velocities, but not obvious at low wind velocities. PMID:28120915

  15. TESTING OF TMR SAND MANTIS FINAL REPORT

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Krementz, D; William Daugherty, W

    2007-06-12

    Screening tests of Sand Mantis candidate materials selected for erosion resistance have been completed. The results of this testing identified that over a relatively short period of operation (<1 hour), measurable erosion will occur in each of the candidate zoom tube materials given equal operating exposure. Additionally, this testing has shown that erosion of the rubber discharge hose directly downstream of the vehicle could be expected to limit the service life of the discharge hose. On the basis of these test results, SRNL recommends the following; {lg_bullet} redesign of critical system components (e.g., zoom tube, discharge hose) should be conductedmore » to improve system characteristics relative to erosion and capitalize on the results of this testing, {lg_bullet} continued efforts to deploy the Sand Mantis should include testing to better define and optimize operating parameters, and gain an understanding of system dynamics, {lg_bullet} discontinue wear testing with the selected materials pending redesign of critical system components (1st recommendation) and inclusion of other candidate materials. The final selection of additional candidate materials should be made following design changes, but might include a Stellite alloy or zirconia.« less

  16. Case history of Yakin Field: its development and sand control

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sawolo, N.; Krueger, R.F.; Maly, G.P.

    1982-01-01

    This study deals with the development of the Yakin Field in E. Kalimantan, Indonesia, with emphasis on the sand control methods used. Implementation of an effective sand control program insured the successful development of this field. Gravel packed wells had substantially lower production decline rates than the initial completions without gravel packs. Control of sand production also has been demonstrated by the lack of sand problems during the 4-1/2 yr since the sand control program was initiated. During this time there have been no failures of submersible pumps that were associated with sand production. The successful sand control program wasmore » achieved by a well coordinated and cooperative effort of drilling, reservoir engineering, production research, and service company personnel.« less

  17. Robotic Transversus Abdominis Release (TAR): is it possible to offer minimally invasive surgery for abdominal wall complex defects?

    PubMed

    Amaral, Maria Vitória França DO; Guimarães, José Ricardo; Volpe, Paula; Oliveira, Flávio Malcher Martins DE; Domene, Carlos Eduardo; Roll, Sérgio; Cavazzola, Leandro Totti

    2017-01-01

    We describe the preliminary national experience and the early results of the use of robotic surgery to perform the posterior separation of abdominal wall components by the Transversus Abdominis Release (TAR) technique for the correction of complex defects of the abdominal wall. We performed the procedures between 04/2/2015 and 06/15/2015 and the follow-up time was up to six months, with a minimum of two months. The mean surgical time was five hours and 40 minutes. Two patients required laparoscopic re-intervention, since one developed hernia by peritoneal migration of the mesh and one had mesh extrusion. The procedure proved to be technically feasible, with a still long surgical time. Considering the potential advantages of robotic surgery and those related to TAR and the results obtained when these two techniques are associated, we conclude that they seem to be a good option for the correction of complex abdominal wall defects. RESUMO Descrevemos a experiência preliminar nacional na utilização da cirurgia robótica para realizar a separação posterior de componentes da parede abdominal pela técnica transversus abdominis release (TAR) na correção de defeitos complexos da parede abdominal e seus resultados precoces. As cirurgias foram realizadas entre 02/04/2015 e 15/06/2015 e o tempo de acompanhamento dos resultados foi de até seis meses, com tempo mínimo de dois meses. O tempo cirúrgico médio foi de cinco horas e 40 minutos. Dois pacientes necessitaram reintervenção por laparoscopia, pois um desenvolveu hérnia por migração peritoneal da tela e um teve escape da tela. A cirurgia provou ser factível do ponto de vista técnico, com um tempo cirúrgico ainda elevado. Tendo em vista as vantagens potenciais da cirurgia robótica e aquelas relacionadas ao TAR e os resultados obtidos ao se associar essas duas técnicas, conclui-se que elas parecem ser uma boa opção para a correção de defeitos complexos da parede abdominal.

  18. Investigation of re-use options for used traction sand.

    DOT National Transportation Integrated Search

    2010-06-01

    The Colorado Department of Transportation (CDOT) uses approximately 24,000 tons of traction sand annually, : especially in mountain locations. Once traction sand is applied, street sweepers reclaim approximately 50% of the : sand, which is either sto...

  19. Petrography, mineralogy, and geochemistry of deep gravelly sands in the Eyreville B core, Chesapeake Bay impact structure

    USGS Publications Warehouse

    Bartosova, Katerina; Gier, Susanne; Horton, J. Wright; Koeberl, Christian; Mader, Dieter; Dypvik, Henning

    2010-01-01

    The ICDP–USGS Eyreville drill cores in the Chesapeake Bay impact structure reached a total depth of 1766 m and comprise (from the bottom upwards) basement-derived schists and granites/pegmatites, impact breccias, mostly poorly lithified gravelly sand and crystalline blocks, a granitic slab, sedimentary breccias, and postimpact sediments. The gravelly sand and crystalline block section forms an approximately 26 m thick interval that includes an amphibolite block and boulders of cataclastic gneiss and suevite. Three gravelly sands (basal, middle, and upper) are distinguished within this interval. The gravelly sands are poorly sorted, clast supported, and generally massive, but crude size-sorting and subtle, discontinuous layers occur locally. Quartz and K-feldspar are the main sand-size minerals and smectite and kaolinite are the principal clay minerals. Other mineral grains occur only in accessory amounts and lithic clasts are sparse (only a few vol%). The gravelly sands are silica rich (~80 wt% SiO2). Trends with depth include a slight decrease in SiO2 and slight increase in Fe2O3. The basal gravelly sand (below the cataclasite boulder) has a lower SiO2 content, less K-feldspar, and more mica than the higher sands, and it contains more lithic clasts and melt particles that are probably reworked from the underlying suevite. The middle gravelly sand (below the amphibolite block) is finer-grained, contains more abundant clay minerals, and displays more variable chemical compositions than upper gravelly sand (above the block). Our mineralogical and geochemical results suggest that the gravelly sands are avalanche deposits derived probably from the nonmarine Potomac Formation in the lower part of the target sediment layer, in contrast to polymict diamictons higher in the core that have been interpreted as ocean-resurge debris flows, which is in agreement with previous interpretations. The mineralogy and geochemistry of the gravelly sands are typical for a passive

  20. Are PAHS the Right Metric for Assessing Toxicity Related to Oils, Tars, Creosote and Similar Contaminants in Sediments?

    EPA Science Inventory

    Oils, tars, and other non-aqueous phase hydrocarbon liquids (NAPLs) are common sources of contamination in aquatic sediments, and the toxicity of such contamination has generally been attributed to component chemicals, particularly PAHs. While there is no doubt PAHs can be toxic ...