Heating tar sands formations to visbreaking temperatures

Science.gov (United States)

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.

Heating tar sands formations while controlling pressure

Science.gov (United States)

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.

A cost comparison of nuclear and fossil power for the Alberta tar sands

International Nuclear Information System (INIS)

Sochaski, R.O.; Smith, D.W.

1977-04-01

One technique envisaged for commercial development of the Alberta tar sands is in-situ removal of bitumen by injection of steam into the formation at high temperature and pressure. The 3000 MW of thermal power required for a typical 20 Gg/d plant could be supplied by a nuclear reactor. Accordingly, an economic comparison was made between a CANDU organic-cooled reactor and a conventional coal-fired station, using a variety of financial ground rules. This analysis shows that for debt-financed cases, nuclear power has essentially no economic competition from coal. For equity cases, the competitive position of a coal-fired station is heavily dependent on the cost of coal delivered to the tar sands area, discount rate, amortization period and inflation rate. (author)

Revegetation and management of tailings sand slopes from tar sand extraction: 1978 results

Energy Technology Data Exchange (ETDEWEB)

Rowell, M J

1979-01-01

The results are reported of research into the revegetation of two areas on a steeply sloping dike composed of tailings sand from tar sand extraction at the Great Canadian Oil Sand Limited plant at Fort McMurray, Alberta. One area was seeded with three pasture grasses and two legumes in 1971 after the slope surface had been mixed with peat to a depth of 15 cm. A second area had been amended with peat or peat and overburden and differing rates of fertilizer added. A mix containing nine grasses, four legumes, and oats, as a companion crop, was seeded in July 1976. The objectives of the research were to study methods for the establishment of a stable vegetative cover that would prevent erosion of the slope and, in time, might become a self maintaining unit. Tillage of soil amendments to a depth of 15 cm and 30 cm were compared in promoting deeper rooting and stabilizing of the slope.

Trace metals in heavy crude oils and tar sand bitumens

Energy Technology Data Exchange (ETDEWEB)

Reynolds, J.G.

1990-11-28

Fe, Ni, and V are considered trace impurities in heavy crude oils and tar sand bitumens. In order to understand the importance of these metals, we have examined several properties: (1) bulk metals levels, (2) distribution in separated fractions, (3) size behavior in feeds and during processing, (4) speciation as a function of size, and (5) correlations with rheological properties. Some of the results of these studies show: (1) V and Ni have roughly bimodal size distributions, (2) groupings were seen based on location, size distribution, and Ni/V ratio of the sample, (3) Fe profiles are distinctively different, having a unimodal distribution with a maximum at relatively large molecular size, (4) Fe concentrations in the tar sand bitumens suggest possible fines solubilization in some cases, (5) SARA separated fractions show possible correlations of metals with asphaltene properties suggesting secondary and tertiary structure interactions, and (6) ICP-MS examination for soluble ultra-trace metal impurities show the possibility of unexpected elements such as U, Th, Mo, and others at concentrations in the ppB to ppM range. 39 refs., 13 figs., 5 tabs.

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

International Nuclear Information System (INIS)

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.

2015-01-01

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. - Highlights: • The potential water quality impacts of the first US tar sand development are considered. • Analyses of perennial springs in adjacent canyons indicate hydrologic

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

Energy Technology Data Exchange (ETDEWEB)

Johnson, William P.; Frederick, Logan E.; Millington, Mallory R. [University of Utah, Department of Geology & Geophysics, Salt lake City, UT 84112 (United States); Vala, David [Murray High School, Murray, UT 84107 (United States); Reese, Barbara K. [Butler Middle School, Cottonwood Heights, UT 84121 (United States); Freedman, Dina R. [Hillside Middle School, Salt Lake City, UT 84108 (United States); Stenten, Christina J. [Draper Park Middle School, Draper, UT 84020 (United States); Trauscht, Jacob S.; Tingey, Christopher E.; Kip Solomon, D.; Fernandez, Diego P.; Bowen, Gabriel J. [University of Utah, Department of Geology & Geophysics, Salt lake City, UT 84112 (United States)

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. - Highlights: • The potential water quality impacts of the first US tar sand development are considered. • Analyses of perennial springs in adjacent canyons indicate hydrologic

Pan Am tar sand bid revealed

Energy Technology Data Exchange (ETDEWEB)

Gray, E

1968-12-16

Muskeg Oil Co., wholly-owned subsidiary of Pan American Canada Oil Co. Ltd., hopes to expand its proposed initial 8,000 bpd in situ Athabasca tar sand production scheme to an ultimate rate of 60,000 bpd. The Muskeg recovery process involves an in situ combustion technique developed by Pan American and applied successfully in experimental work in the Athabasca area. The underground burning process develops heat in the formation, reduces crude bitumen viscosity, and displaces the bitumen to the producing wells. Core analyses have been used to determine bitumen in place, wherever possible. Values for uncored wells were based on logs, through development of an empirical relationship between formation resistivity measured by focused logging devices and bitumen content determined by core analysis. The proposed recovery process is a 10-acre well spacing with 9-spot configuration. The McMurray Formation will be fractured hydraulically and preheated by a combustion process. The bitumen will be recovered by a combustion displacement process utilizing air and water.

Economic and environmental effects of the FQD on crude oil production from tar sands

Energy Technology Data Exchange (ETDEWEB)

Kampman, B.; De Buck, A.; Afman, M. [CE Delft, Delft (Netherlands); Van den Berg, J.; Otten, G.J. [Carbon Matters, Den Haag (Netherlands)

2013-05-15

The production of unconventional crudes in Canada and Venezuela and exports of these crudes to the EU are investigated. In addition the potential economic and environmental impact of the proposed EU FQD measures (Fuel Quality Directive) on the production of crudes from tar sands and on new tar sand exploration projects are examined. CE Delft has analysed the impact by using a dedicated cost model. For existing projects, the model determines the effect on the basis of marginal production costs. For planned projects the model used the net present value (NPV) of proposed investments. The impacts were determined for a range of crude oil prices and FQD price effects. Combined, for existing and new projects together, the maximum effect would be at a price level at 60 USD/bbl, with savings of up to 19 Mt CO2/y at an FQD price differential of 3 euro/bbl. This overall effect would be substantial and come on top of the total emission reduction effect of the FQD of 60 Mt CO2/y, which will be achieved mostly by the blending of low-carbon fuels and reduced flaring and venting. As part of the reduction of transport greenhouse gas (GHG) emissions, the revised FQD obliges fuel suppliers to reduce these emissions by 6% by 2020 on a well-to-wheel basis. The EU is currently developing a methodology to differentiate fossil fuels on the basis of feedstock and GHG emissions. In the proposal, diesel produced from tar sands, has been given a default emission value of 108.5 gCO2 eq/MJ, while diesel from conventional crude was set at 89.1 gCO2 eq/MJ. The Commission's proposal is currently undergoing an impact assessment and is expected to be resubmitted to the Council later this year (2013)

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

Energy Technology Data Exchange (ETDEWEB)

Linberg, W.R.

1980-09-10

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.

Cashing in on Tar Sands. RBS, UK banks and Canada's 'blood oil'

Energy Technology Data Exchange (ETDEWEB)

Evans, M.; Howarth, C.; Kellay, A.; Laboucan, B.J.; Mercredi, M.; Minio-Paluelo, M.; Schling, H.; Smith, K.; Thomas-Muller, C.; Wood, A.

2010-03-15

Tar sands extraction in Canada is devastating Indigenous communities, wildlife and vast areas of boreal forests, as well as being many times more carbon-intensive to produce than 'conventional' oil. The higher oil prices in recent years have meant that it's become a more attractive prospect for oil companies to expand their operations in the costly process of obtaining and processing the thick bitumen into a usable form. It's estimated that the industry is looking for a capital investment of 120-220 billion USD over the next 20 years to build the new pipelines, mines, refineries and upgraders that are necessary to sustain the boom. This report looks at the role that UK banks are playing in providing the necessary capital, and how RBS (Royal Bank of Scotland), which is 84% owned by the UK public, has been the bank the most heavily involved in underwriting loans to companies engaging in tar sands extraction.

1170-MW(t) HTGR-PS/C plant application study report: tar sands oil recovery application

International Nuclear Information System (INIS)

Rao, R.; McMain, A.T. Jr.

1981-05-01

This report summarizes a study to apply an 1170-MW(t) high-temperature gas-cooled reactor - process steam/cogeneration (HTGR-PS/C) to tar sands oil recovery and upgrading. The raw product recovered from the sands is a heavy, sour bitumen; upgrading, which involves coking and hydrodesulfurization, produces a synthetic crude (refinable by current technology) and petroleum coke. Steam and electric power are required for the recovery and upgrading process. Proposed and commercial plants would purchase electric power from local utilities and obtain from boilers fired with coal and with by-product fuels produced by the upgrading. This study shows that an HTGR-PS/C represents a more economical source of steam and electric power

Environmental survey - tar sands in situ processing research program (Vernal, Uintah County, Utah). [Reverse-forward combustion; steam injection

Energy Technology Data Exchange (ETDEWEB)

Skinner, Q.

1980-03-01

Research will be done on the reverse-forward combustion and steam injection for the in-situ recovery of oil from tar sands. This environmental survey will serve as a guideline for the consideration of environmental consequences of such research. It covers the construction phase, operational phase, description of the environment, potential impacts and mitigations, coordination, and alternatives. (DLC)

Retorting of bituminous sands

Energy Technology Data Exchange (ETDEWEB)

Chaney, P E; Ince, R W; Mason, C M

1872-09-26

This method of recovering oil from mined tar sands involves forming compacted tar sands pieces by special conditioning treatment that provides low internal permeability. The compacted pieces are then retorted in fixed bed form. The conditioning treatment can involve rolling of preformed pellets, compaction in a mold or pressure extrusion. Substantial collapsing of the bed during retorting is avoided. (9 claims) (Abstract only - original article not available from T.U.)

Chemical modification of a bitumen and its non-fuel uses. [Reactions of tar sand asphaltenes in synthesis of non-fuel products

Energy Technology Data Exchange (ETDEWEB)

Moschopedis, S.E.; Speight, J.G.

1974-01-01

Simple reactions are described whereby tar sand bitumen can be converted to a whole range of materials. Examples are given to illustrate the non-fuel uses of the products. The following reactions of Athabasca asphaltenes are considered: oxidation, halogenation, sulfonation and sulfomethylation, phosphorylation, hydrogenation, reactions with S and O, reactions with metal salts, and miscellaneous chemical conversions. (JGB)

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

Energy Technology Data Exchange (ETDEWEB)

Oblad, A.G.; Bunger, J.W.; Dahlstrom, D.A.; Deo, M.D.; Fletcher, J.V.; Hanson, F.V.; Miller, J.D.; Seader, J.D.

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.

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

Energy Technology Data Exchange (ETDEWEB)

Oblad, A.G.; Bunger, J.W.; Dahlstrom, D.A.; Deo, M.D.; Hanson, F.V.; Miller, J.D.; Seader, J.D.

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 (approximately 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.

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

Science.gov (United States)

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.

Study on Tar Generated from Downdraft Gasification of Oil Palm Fronds

Directory of Open Access Journals (Sweden)

Samson Mekbib Atnaw

2014-01-01

Full Text Available 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.

Study on Tar Generated from Downdraft Gasification of Oil Palm Fronds

Science.gov (United States)

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

Coal Tar and Coal-Tar Pitch

Science.gov (United States)

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.

A Critical Review of the Oil and Tar Sands of the Dahomey Basin

International Nuclear Information System (INIS)

Osundina, A.; Mustapha, A.; Nzewi, T.

2002-01-01

The Benin Basin previously referred to as the Dahomey embayment has been designated as a frontier basin within Nigeria due to its potentially high prospects, but comparatively low exploitation campaign to date. The basin offers a promising opportunity for heavy oil exploration in a narrow belt extending westward from Edo State to the republic of Benin; while offshore, there are high prospects for finding more conventional hydrocarbon.The eastern Dahomey embayment is known to have an extensive reserve of hydrocarbons (bitumen and tar sands). The sediments occur in a 5 8 km belt stretching 120km from the fringes of Lagos State through Ogun, Ondo and Edo States. The estimated reserve potentials exceed 30 billion barrels of oil equivalent.Recently acquired seismic data in OPL 309 and 310, and subsequent drilling of 2 wells on the narrow continental shelf, have shown the presence of closed structures over Basement Highs and other related structural styles in the basin and confirm that conventional light oils and condensates hydrocarbons occur in commercial quantity. These hydrocarbons are reservoired in stratigraphic sequences of Albian Cenomanian age.This paper hopes to expose the hidden riches of this Basin and hopefully get the attention of the big players in refocusing their interests in the basin that attracted attention of the early petroleum explorers to Nigeria approximately 100 years ago

Reports on 1974 result of Sunshine Project. Research on tar sand and oil shale; 1974 nendo tar sand oyobi oil shale ni kansuru chosa kenkyu seika hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1975-04-04

The purpose of this research is to grasp the policy of the oil sand resource countries, the properties and existing conditions of the resources, effects of the oil sand resources on a long term energy supply/demand, etc., and to clarify the meaning and position of the researches on the development of oil sand resources in the future energy policy of Japan. The quantities of oil sand resources are mostly in the process of investigation except Alberta province of Canada and are estimated to be two trillion barrels. The quantity for which strip mining is possible is about 90 billion barrels, which are mostly located in the Athabasca region. The oil sand holding countries take a policy of positively developing oil sand. No barriers are particularly provided against the introduction of foreign technology and capital. Where the prospects are possible for the development of oil sand are Canada and Venezuela. R and D should be emphasized on the refining of bitumen and the extraction method within the oil reservoir. The investment per b/d is about 15-20 thousand dollars, which is likely to be more than twice as much as for the North Sea oilfields. The properties and quality of the synthetic crude oil are superior while the risk of exploitation is small; therefore, oil sand will be competitive with crude oil in the future. (NEDO)

Canada's oil sands: nuclear power in an integrated energy economy

Energy Technology Data Exchange (ETDEWEB)

Isaacs, E. [Alberta Energy Research Inst., Calgary, Alberta (Canada)

2008-07-01

This paper discusses the role of nuclear power in Canada's oil sands industry. It outlines the oil sands resource in Alberta and the various industrial projects to recover the oil from the tar sands. It points to continuing innovation in technology since the 1930's. The hydrogen required for upgrading bitumen is made from natural gas. Finally, it discusses the next wave of oil sands production technologies.

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

International Nuclear Information System (INIS)

Lowe, N.J.; Wortzman, M.S.; Breeding, J.; Koudsi, H.; Taylor, L.

1983-01-01

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 to 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

A DEVICE AND METHOD FOR MEASURING TAR IN A TAR-ENVIRONMENT

DEFF Research Database (Denmark)

2017-01-01

The present disclosure describes a device and corresponding method for measuring tar in a tar environment, e.g., a tar producing environment such as a stove or a combustion engine, based on UV absorption spectroscopy. A first measurement along an optical path in the tar environment is performed...

Western Research Institute: Annual technical progress report, October 1987--September 1988

Energy Technology Data Exchange (ETDEWEB)

1988-12-01

This report describes the technical progress made by the Western Research Institute of the University of Wyoming Research Institute of the University of Wyoming Research Corporation on work performed for the period October 1, 1987 through September 30, 1988. This research involves five resource areas: oil shale, tar sand, underground coal gasification, advanced process technology, and advanced fuels research. Under the terms of the cooperative agreement, an annual project plan has been approved by DOE. The work reported herein reflects the implementation of the research in the plan and follows the structure used therein. 49 refs., 32 figs., 87 tabs.

Centennial review-forecast--oil sands, shales spar for markets

Energy Technology Data Exchange (ETDEWEB)

Pamenter, C B

1967-09-01

The relationship between possible developments of tar sands and oil shale deposits to the future of the oil and gas industry is examined. The Athabasca tar sands are estimated to contain 85 billion bbl of synthetic crude oil which can be exploited using currently available mining equipment and proven techniques. Another 240 billion bbl of synthetic crude are potentially available through in-situ extraction methods. Great Canadian Oil Sands Ltd. is using an extraction procedure which involves a surface mining operation, extraction and processing of the bitumen, and product shipments via a 266-mile pipeline. This procedure will be used to produce 45,000 bpd of synthetic crude and 300 ton per day of sulfur. Syncrude Canada Ltd. and Shell Canada Ltd. both have applied to the Alberta government for permission to operate 100,000-bpd operations. Syncrudes is a mining operation and Shell plans to use in-situ extraction. A number of companies have conducted research projects concerning shale oil recovery. The majority of these projects have been aimed at improving mining operations. In-situ retorting of kerogen and extraction of oil has also received consideration.

Coal tar in dermatology

Energy Technology Data Exchange (ETDEWEB)

Roelofzen, J.H.J.; Aben, K.K.H.; Van Der Valk, P.G.M.; Van Houtum, J.L.M.; Van De Kerkhof, P.C.M.; Kiemeney, L.A.L.M. [Radboud University Nijmegen Medical Center, Nijmegen (Netherlands). Dept. of Dermatology

2007-07-01

Coal tar is one of the oldest treatments for psoriasis and eczema. It has anti-inflammatory, antibacterial, antipruritic and antimitotic effects. The short-term side effects are folliculitis, irritation and contact allergy. Coal tar contains carcinogens. The carcinogenicity of coal tar has been shown in animal studies and studies in occupational settings. There is no clear evidence of an increased risk of skin tumors or internal tumors. Until now, most studies have been fairly small and they did not investigate the risk of coal tar alone, but the risk of coal tar combined with other therapies. New, well-designed, epidemiological studies are necessary to assess the risk of skin tumors and other malignancies after dermatological use of coal tar.

Sedimentological and Scanning Electron Miscroscopic Descriptions of Afowo Oil Sand Deposits, South Western Nigeria

Directory of Open Access Journals (Sweden)

Akinmosin A

2017-12-01

Full Text Available Sedimentological and scanning electron microscopic analyses of some shallow reservoir tar sand samples in parts of Southwestern Nigeria were carried out with the aim of characterizing the reservoir properties in relation to bitumen saturation and recovery efficiency. The production of impregnated tar from the sands requires the reservoir to be of good quality. A total of thirty samples were collected at different localities within the tar sand belt (ten out of these samples were selected for various reservoir quality analyses based on their textural homogeneity. The result of particle size distribution study showed that bulk of the sands is medium – coarse grained and moderately sorted. The grain morphologies are of low to high sphericity with shapes generally sub-angular to sub-rounded, implying that the sands have undergone a fairly long transportation history with depositional energy having a moderate to high velocity. The quartz content was made up of about 96% of the total mineralogical components; the sediments of the Afowo Formation can be described to be mineralogically and texturally stable. The result of the scanning electron microscopy (SEM analysis revealed that the oil sands contained minerals which had been precipitated and occurred as pore filling cement; these minerals include sheet kaolinite, block kaolinite, vermiform kaolinite, pyrite crystals and quartz. The SEM images also showed micro-pores ranging from 0.057µm to 0.446µm and fractures. The study showed that the clay minerals contained in the Afowo reservoir rocks were mainly kaolinite. Kaoline unlike some other clays (e.g Montimorillonite does not swell with water, hence it is not expected to have any negative effects on the reservoir quality, especially during enhanced oil recovery operations.

Oil sands to the rescue: oil sand microbial communities can degrade recalcitrant alkyl phenyl alkanoic acids

Energy Technology Data Exchange (ETDEWEB)

Whitby, Corinne [University of Essex (Canada)], email: cwhitby@essex.ac.uk

2011-07-01

Almost half of all global oil reserves are found as biodegraded heavy oils found in vast tar sand deposits located in North and South America and these account for 47% of Canadian oil production. Oil sand extraction generates large amounts of toxic waste water, known as oil sand process waters (OSPW), that are stored in large tailing ponds that contain toxic compounds like naphthenic acids (NAs). The presence of NAs creates problems like toxicity, corrosion, and the formation of calcium napthenate deposits which block pipelines and other infrastructure and need to be removed. This paper presents oil sand microbial communities that can degrade these NAs. The approach is to apply new aliphatic and aromatic NAs as substrates to supplement and identify NA degrading microbes and also to identify the metabolites produced and explain NA degradation pathways and the functional genes involved. The chemistry and the processes involved are explained. From the results, it is suggested that pure cultures of P. putida KT2440 be used against NAs.

Characterization and utilization of hydrotreated products produced from the Whiterocks (Utah) tar sand bitumen-derived liquid

Energy Technology Data Exchange (ETDEWEB)

Tsai, C.H.; Longstaff, D.C.; Deo, M.D.; Hanson, F.V.; Oblad, A.G.

1991-12-31

The bitumen-derived liquid produced in a 4-inch diameter fluidized-bed reactor from the mined and crushed ore from the Whiterocks tar sand deposit has been hydrotreated in a fixed-bed reactor. The purpose was to determine the extent of upgrading as a function of process operating variable. A sulfided nickel-molybendum on alumina hydrodenitrogenation catalyst was used in all experiments. Moderately severe operating conditions were employed; that is, high reaction temperature (617--680 K) high reactor pressure (11.0--17.1 MPa) and low liquid feed rate (0.18--0.77 HSV); to achieve the desired reduction in heteroatom content. Detailed chemical structures of the bitumen-derived liquid feedstock and the hydrotreated total liquid products were determined by high resolution gas chromatography - mass spectrometry analyses. The compounds identified in the native bitumen included isoprenoids; bicyclic, tricycle, and tetracyclic terpenoids; steranes; hopanes; and perhydro-{beta}-carotenes. In addition, normal and branched alkanes and alkenes and partially dehydrogenated hydroaromatics were identified in the bitumen-derived liquid. The dominant pyrolysis reactions were: (1) the dealkylation of long alkyl side chains to form {alpha} - and isoolefins; and (2) the cleavage of alkyl chains linking aromatic and hydroaromatic clusters. Olefinic bonds were not observed in the hydrotreated product and monoaromatic hydrocarbons were the predominant aromatic species. The properties of the jet fuel fractions from the hydrotreated products met most of the jet fuel specifications. The cetane indices indicated these fractions would be suitable for use as diesel fuels.

Characterization and utilization of hydrotreated products produced from the Whiterocks (Utah) tar sand bitumen-derived liquid

Energy Technology Data Exchange (ETDEWEB)

Tsai, C.H.; Longstaff, D.C.; Deo, M.D.; Hanson, F.V.; Oblad, A.G.

1991-01-01

The bitumen-derived liquid produced in a 4-inch diameter fluidized-bed reactor from the mined and crushed ore from the Whiterocks tar sand deposit has been hydrotreated in a fixed-bed reactor. The purpose was to determine the extent of upgrading as a function of process operating variable. A sulfided nickel-molybendum on alumina hydrodenitrogenation catalyst was used in all experiments. Moderately severe operating conditions were employed; that is, high reaction temperature (617--680 K) high reactor pressure (11.0--17.1 MPa) and low liquid feed rate (0.18--0.77 HSV); to achieve the desired reduction in heteroatom content. Detailed chemical structures of the bitumen-derived liquid feedstock and the hydrotreated total liquid products were determined by high resolution gas chromatography - mass spectrometry analyses. The compounds identified in the native bitumen included isoprenoids; bicyclic, tricycle, and tetracyclic terpenoids; steranes; hopanes; and perhydro-{beta}-carotenes. In addition, normal and branched alkanes and alkenes and partially dehydrogenated hydroaromatics were identified in the bitumen-derived liquid. The dominant pyrolysis reactions were: (1) the dealkylation of long alkyl side chains to form {alpha} - and isoolefins; and (2) the cleavage of alkyl chains linking aromatic and hydroaromatic clusters. Olefinic bonds were not observed in the hydrotreated product and monoaromatic hydrocarbons were the predominant aromatic species. The properties of the jet fuel fractions from the hydrotreated products met most of the jet fuel specifications. The cetane indices indicated these fractions would be suitable for use as diesel fuels.

Treatment of lignite tars, etc

Energy Technology Data Exchange (ETDEWEB)

1936-08-07

A process is described for treating tars such as lignite tar, shale tar, or peat tar, and similar tars, characterized by the fact that the tar is rectified to about 240/sup 0/C and the residue brought to a temperature above 50/sup 0/C after diluting with a product of the type of gasoline or ligroin at about 30/sup 0/C and treated with selective solvents preferably low-boiling phenols and eventually with water.

Indian coal tars. II

Energy Technology Data Exchange (ETDEWEB)

Basu, A N; Bhatnagar, J N; Roy, A K

1954-01-01

Laboratory experiments were carried out on these efforts: (1) rank and specific-gravity fractions on tar yield; (2) addition of water to the coal charge, or steam during carbonization, on yield of tar and tar acids; (3) the presence of a cracking agent (shale) with and without steam addition on the yield of tar and tar acids (the particular shale used without steam reduced the yield, and the restricted use of steam brought the yield to the former noncatalyzed level); and (4) catalytic effect of three different samples of shale, firebrick, quartz, coke, and silica-alumina on the cracking of tar acids (the most active were two of the shales, a freshly-prepared coke, and the Al/sub 2/O/sub 3/-SiO/sub 2/ catalysts that gave conversion up to 98%). The products were mainly carbon, aromatic hydrocarbons of the naphthalene series and gases (CO and H/sub 2/). The yield of the tar becomes less as coal of lower specific gravity is used or when higher temperatures are used for carbonization. The mineral matter associated with Indian coals acts as a decomposition catalyst for tar acids, as shown by experiments on the decomposition of PhOH at temperatures above 800/sup 0/.

Tar bases in low-temperature coal tar

Energy Technology Data Exchange (ETDEWEB)

Sugiura, S; Ueno, H; Yokoyama, H

1951-01-01

Tar bases were extracted from three fractions, that boil below 260/sup 0/ at 260/sup 0/ to 280/sup 0/, and 280/sup 0/ to 330/sup 0/, respectively, of the low-temperature tar obtained by the carbonization of Ube coal in a Koppers' vertical retort at approximately 750/sup 0/. These were divided, respectively, into three groups, acetate-forming amine, HCl salt-forming bases (I), and CHCl/sub 3/-soluble bases (II), and further fractionally distilled. From the physical and chemical properties of the fractions thus obtained, it was concluded that low-temperature coal tar contained no low boiling pyridine homologues and that, besides higher homologues of pyridine, nonaromatic, more saturated, and less basic compounds of larger atomic weight and smaller refractive index, such as derivatives of pyrrole and indole, also existed as in crude petroleum.

Process of treating tars

Energy Technology Data Exchange (ETDEWEB)

Hansen, C; Hempel, H; Weissenburger, H

1955-05-05

A process is described for treating tars or tar oils, especially carbonization tars, characterized in that the tars or tar oils are mixed with benzene or light oils which contain no aromatic material or only slight amounts, or with gas oil in such amounts that the asphalt precipitates, and after separation of the precipitated material the mixture is treated with caustic solution for separation of the phenols, and after separation of the phenolate liquor the mixture is subjected to heating for removal of the dilution medium, then the remaining oil can be used as heating oil or it is submitted to distillation for the purpose of recovering a fuel suitable for diesel motors, while the phenolate liquor is worked up into phenols.

Topical tar: Back to the future

Energy Technology Data Exchange (ETDEWEB)

Paghdal, K.V.; Schwartz, R.A. [University of Medicine & Dentistry of New Jersey, Newark, NJ (United States)

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 clearing 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.

Removing tar information from cigarette packages may reduce South Korean smokers' misconceptions about low-tar cigarettes

Directory of Open Access Journals (Sweden)

Hye-Jin Paek

2018-03-01

Full Text Available Background Many smokers still have misconceptions about “light” or “low tar” cigarettes. In South Korea, low-tar (< 3 mg cigarette sales have increased sharply from 1.8% in 2002 to 49.2% in 2015. Although government regulations forbid cigarette packages from displaying messages such as “mild,” “low-tar,” and “light,” numbers indicating tar amounts are still permitted. This study examines whether removing tar information from packaging altogether reduces people's misconceptions about low tar cigarettes. Methods An online experiment was conducted among 531 smokers who were randomly assigned to one of two conditions. In the “tar” condition, 271 participants were shown in random order three cigarette packages for three major brands (Esse, The One, Marlboro with different tar amounts. In the “no-tar” condition, 260 participants were shown the same packages without tar information. Next, participants evaluated which type of cigarette was mildest, least harmful, easier for nonsmokers to start smoking, and easier for smokers to quit. After descriptive statistics were checked, twelve sets of chi-square tests were performed. Results Average age of the participants was 26.22 (14 - 62 years; 53.5% were male. All 12 chi-square tests were statistically significant. Participants in the tar condition judged the lowest-tar cigarette to be mildest, least harmful, easier to start, and easier to quit. In the no-tar condition, for the Korean brands Esse and The One, most respondents evaluated all cigarette types to be the same only for harm, ease of starting, and ease of quitting; for Marlboro, judgments were the same as those in the tar condition except that “easier to quit” was judged to be the same across the three types. Conclusions Banning tar information from cigarette packages may help reduce smokers' misconceptions about low-tar cigarettes. People have inconsistent judgments about differently packaged cigarettes when tar

Distilling tar; distillation, destructive

Energy Technology Data Exchange (ETDEWEB)

Brash, P; Young, W

1866-09-17

The tarry residue, which separates on treating crude shale oil with sulfuric acid, is redistilled, in the manner described in Specification No. 1278, A.D. 1866, together with shale. Previous to the distillation, the acid is neutralized with lime, or may be separated by blowing steam into the tar and adding salt. The purified tar thus obtained is absorbed by ashes, or is mixed with lime or other alkaline matter, or the shale may be mixed with lime and distilled with the tar, which is allowed to flow over and through the shale during the process. The tar obtained in the purification of natural paraffin may be similarly utilized.

Summary of research and information needs for the management of selected onshore energy minerals: oil shale, tar sands, arctic oil and gas, and uranium. Final report 1982-83

Energy Technology Data Exchange (ETDEWEB)

1983-11-01

The report assesses research needs for the management, regulation, reclamation, and conservation of oil shale, tar sands, arctic oil and gas, and uranium deposits currently under federal jurisdiction and concludes that additional research is required to achieve the goals of good management, including conservation, protection of life and property, and minimization of environmental degradation. The report recommends (1) establishment of a standing advisory scientific and engineering committee on onshore minerals management research to influence future research directions and implementation; (2) development of a comprehensive library and data center for research results; and (3) encouragement of the operation of demonstration-scale production facilities where they are lacking. More detailed summaries of current knowledge and perceived research needs are to be found in the four interim reports of the committee.

The extraction of bitumen from western oil sands

International Nuclear Information System (INIS)

Oblad, A.G.; Bunger, J.W.; Dahlstrom, D.A.; Deo, M.D.; Hanson, F.V.; Miller, J.D.; Seader, J.D.

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 (approximately 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

Effect of Carbon and Nitrogen Sources on Polygalacturonase Production by Trichoderma viride (BITRS-1001 Isolated from Tar Sand in Ondo State, Nigeria

Directory of Open Access Journals (Sweden)

Ogunmolu, F. E.

2011-01-01

Full Text Available The effects of the various carbon and nitrogen substrates on the growth and polygalacturonase activity of Trichoderma viride (BITRS-1001 isolated from the tar sand deposit in Gbelejuloda-Irele Ondo State, Nigeria were investigated in submerged cultivation at 30 °C ± 2 °C. The commercial carbon and nitrogen substrates included sucrose, fructose, starch, maltose, lactose and peptone, sodium nitrate, urea and casein respectively. All the carbon substrates used supported the growth of T. viride (0.566 to 0.156 g/50 mL of culture medium with starch supporting the highest biomass yield and sucrose the least biomass yield. Maximum polygalacturonase activity of 3033 U/mL was recorded in maltose medium. Maximum biomass yield on the nitrogen sources was observed in the organic nitrogen namely peptone and casein with values not significantly different from each other at p ≤ 0.05. In the determination of the crude enzyme activity on the nitrogen sources, maximum polygalacturonase activity of 12,400 U/mL was recorded in peptone medium. Hence, a careful manipulation of these nutrient substrates could help to optimise the production of this enzyme on a large scale.

Upgrading of hydropyrolysis coal tar by hydroprocessing

Energy Technology Data Exchange (ETDEWEB)

Haglund, R.; Otterstedt, J.E.; Sterte, J. (Chalmers Univ. of Tech., Goeteborg (Sweden). 1. Dept. of Engineering Chemistry)

1991-05-01

Upgrading of a hydropyrolysis coal tar by hydroprocessing was investigated using different process conditions. The response of the hydropyrolysis tar to hydroprocessing was compared to those of a conventional coal tar and two heavy oil fractions. At comparable conditions, the removal of heteroatoms from the hydropyrolysis tar was more effective than from the conventional tar and, in particular, than from the oil fractions. Using conditions typical for hydroprocessing of heavy oil fractions, the contents of N, O as well as S in the hydropyrolysis tar were reduced by more than 90%. Hydroprocessing also resulted in a considerable increase in the gasoline fraction of the tar. (orig.).

Athabasca tar sands as a source of crude oil

Energy Technology Data Exchange (ETDEWEB)

Montgomery, D S

1964-01-01

A general review is presented of the variable nature of the Athabasca bituminous sand resource, and the chemical composition of the bitumen is given at various stages during the refining from raw material to finished products. The research conducted at the Mines Branch, Ottawa, on vapor-phase hydrogenation of coker distillates is described, emphasizing the effect of hydrogen pressure on the rate of catalyst deactivation. The quality of the hydrogenated products is described in general terms and some observations are made on the reasons why large-scale operation is essential if an economical process is to be achieved.

Providing floating capabilities in latest-generation sand screens

Energy Technology Data Exchange (ETDEWEB)

Bowen, E.G.; Coronado, M.P. [Society of Petroleum Engineers, Richardson, TX (United States)]|[Baker Hughes, Houston, TX (United States)

2008-10-15

Alternative production methods are needed for the massive reserves located in the bitumen region of Canada's tar sands. The area has over 100 installations of sand screens/slotted liners in both injection and production legs using steam-assisted gravity drainage (SAGD) technology. Multiple wells must be drilled from a single pad because of the sensitive nature of the environment. With significant depths of these wells, a floating sand screen provides assurance that the sand screen will reach the desired depth. Paraffin is generally used to plug the flow access of the screen during installation. This paper discussed a new technology that has been developed to allow for sand screen installations without relying on paraffin wax to withstand differential pressure. The new technology uses a hydro-mechanical valving system incorporated into the screen design to temporarily close off the screen while being run in the hole. The paper described how the technology could provide a reliable, time-saving solution for SAGD installations when floating sand control screens are needed. The paper discussed current technology and its limitations, sand screen installation, screen design for floating applications, and additional applications. It was concluded that this technology solution provides a unique alternative to the methods currently used to install sand screens with SAGD technology in the fast growing Canadian market for bitumen recovery. 2 refs., 5 figs.

Preparation of pure phenols from tars

Energy Technology Data Exchange (ETDEWEB)

Meyer, J

1933-02-07

A process is disclosed for the preparation of pure phenols from brown coal tar, shale tar, or primary tar, characterized in that the raw oil obtained from the tar is carefully fractionated, in a suitable way without or with a slight pressure decrease, or before the fractionation the raw oil is heated to free the prepared phenolate solution from impurities after successful oxidation by passing in steam at a temperature between 100 and 120/sup 0/C.

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

Data.gov (United States)

U.S. Environmental Protection Agency — 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...

Analysis of tars produced in biomass gasification

Energy Technology Data Exchange (ETDEWEB)

Zhou, J.; Wang, Y.; Kinoshita, C.M. [Univ. of Hawaii, Honolulu, HI (United States)

1993-12-31

Parametric tests on tar formation, varying temperature, equivalence ratio, and residence time, are performed on a bench-scale, indirectly-heated fluidized bed gasifier. Prepared tar samples are analyzed in a gas chromatograph (GC) with a flame ionization detector, using a capillary column. Standards containing dominant tar species have been prepared for GC calibration. The identified peaks include single-ring hydrocarbons, such as benzene, to five-ring hydrocarbons, such as perylene; depending on the gasification conditions, the identified species represent about 70 to 90% (mass basis) of the tar constituents. Under all conditions tested, benzene and naphthalene were the most dominant species. Temperature and equivalence ratio have significant effect on tar yield and tar composition. Tar yield decreases with increasing temperature or equivalence ratio. The test results suggest that lower temperature favors the formation of more aromatic tar species with diversified substituent groups, while higher temperature favors the formation of fewer aromatic tar species without substituent groups. Higher temperature or equivalence ratio favors the formation of polyaromatic compounds. Oxygen-containing compounds exist in significant quantities only at temperature below 800{degrees}C and decrease with increasing temperature, equivalence ratio, or residence time.

Determination of phenol in tar

Energy Technology Data Exchange (ETDEWEB)

Dierichs, A; Heinichen, G

1955-01-01

During low-temperature carbonization of lignite, the phenols and other oxygenated compounds appear both in the aqueous-process liquor and in the tar. Measurements of these oxygenated components resulting from low-temperature carbonization may serve as a parameter for the classification of lignites. However, such measurements are complicated by the instability of the tar and the complex nature of some of the acidic substances. Difficulties with the previous methods of analysis are reviewed. The present method outlines separation of aqueous-process liquor from lignite tar in a Fischer retort, followed by determination of phenols and fatty acids in the tar phase. The jacketed tar receiver is washed with 300 milliliter xylol and treated with aqueous caustic washes. Neutral oils are separated from the aqueous alkali solution. It is then extracted with ether and finally acidified with HCl. Solids are filtered off, and phenols and fatty acids are separated by Na/sub 2/CO/sub 3/ solution.

Hydroconversion of coal tars: effect of the temperature of pyrolysis on the reactivity of tars

Energy Technology Data Exchange (ETDEWEB)

Lemberton, J.L.; Touzeyidio, M.; Guisnet, M.

1988-12-01

The hydroconversion of a low-temperature and of a high-temperature tar was carried out in the presence of a sulfided Ni and Mo on alumina catalyst - pure or mixed with an acid catalyst (HY zeolite). Significant amounts of light products can be obtained from low temperature tar, formed however through a non-catalytic process. On the contrary, there is a slight catalytic effect during the hydroprocessing of high temperature tar, but the yield in light products is very low. These results can be explained by an extensive poisoning of the NiMo on alumina catalyst by coke which is initiated by the O- and N-containing compounds of the tars. 10 refs., 1 fig., 3 tabs.

Dehydration of hydrated low-temperature tar

Energy Technology Data Exchange (ETDEWEB)

Yoshida, T

1949-01-01

Yoshida examined the mechanism of the dehydration of hydrated low-temperature tar with a microscope. The tar containing free carbon and coal dust is so stable that the removal of the above substances and water by a physical method is very difficult. Addition of light oil produced by fractionation of low-temperature tar facilitates the operations. Yoshida tried using the separate acid, neutral, and basic components of the light oil; the acid oil proved to be most effective. For many reasons it is convenient to use light oil as it is. In this method the quantity of light oil required is 2 to 3 times that of tar. But in supplementing the centrifugal method, the quantity of light oil needed might be only half the amount of tar.

Separating cresote from tars, mineral oils, etc

Energy Technology Data Exchange (ETDEWEB)

Erdmann, E

1921-01-07

Phenolic bodies are extracted from tars such as lignite, shale, peat, coal, producer and low temperature tars, and from tar distillates and residues and from mineral oils and distillates by washing with a mixture of acetone and water. Acetone extracts of the tars etc., may be mixed with water or aqueous acetone to cause the separation of the oils, while the creosote remains in solution.

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

Science.gov (United States)

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%.

Bioremediation potential of coal-tar-oil-contaminated soil

International Nuclear Information System (INIS)

Lajoie, C.A.

1991-01-01

The bioremediation of coal tar oil contaminated soil was investigated in 90 day laboratory simulation experiments. The effect of soil moisture, humic acid amendment, and coal tar oil concentration on the rate of disappearance of individual coal tar oil constituents (PAHs and related compounds) was determined by methylene chloride extraction and gas chromatography. Mass balance experiments determined the fate of both the individual 14 C-labeled PAHs phenanthrene, pyrene, and benzo(a)pyrene, and the total coal tar oil carbon. Mineralization, volatilization, incorporation into microbial biomass, disappearance of individual coal tar oil constitutents, and the distribution of residual 14 C-activity in different soil fractions were measured. The rate of disappearance of coal tar oil constituents increased with increasing soil moisture over the experimental range. Humic acid amendment initially enhanced the rate of disappearance, but decreased the extent of disappearance. The amount of contamination removed decreased at higher coal tar oil concentrations. The practical limit for biodegradation in the system tested appeared to be between 1.0 and 2.5% coal tar oil. Mineralization accounted for 40 to 50% of the applied coal tar oil. Volatilization was a minor pathway of disappearance

Literature search on the environmental impacts of tar sands operations

International Nuclear Information System (INIS)

Birkholz, D.; Prendergast, S.

1990-09-01

An extensive review is presented of the literature on the chemistry and biological impacts of current and potential effluents and discharges from oil sands plants on the Athabasca River. The pollutant compounds of interest included polycyclic aromatic hydrocarbons, methyl homologues and metabolites, polycyclic aromatic sulfur heterocycles, polycyclic aromatic nitrogen heterocycles, and naphthenic acids. Topics of interest include chemical methods for identifying and quantitating the above compounds and their metabolites, their sources and release rates, their toxicity to native fish of the Athabasca system, and their degradation in the natural environment. 376 refs., 4 figs., 26 tabs

Process and apparatus for recovering of oil, bitumen, tar, resins, etc

Energy Technology Data Exchange (ETDEWEB)

1921-11-06

A process for recovering oil, bitumen, tar, and resins from oil shale, oil sands, Fuller's earth, peat, brown coal, mineral coal, and wood, through direct action of superheated steam on the material, is characterized by the fact that superheated steam with or without mixing of inert gases at a temperature, which lies below the decomposition temperature of the material being treated, is passed through the material with a high velocity. It leaves through nozzles, used in steam turbines. A method of carrying out the process in which solution medium is used for action on the material is characterized by the fact that solvents such as benzine and benzol are mixed with steam in different quantities.

Centrifuge treatment of coal tar

Energy Technology Data Exchange (ETDEWEB)

L.A. Kazak; V.Z. Kaidalov; L.F. Syrova; O.S. Miroshnichenko; A.S. Minakov [Giprokoks, the State Institute for the Design of Coke-Industry Enterprises, Kharkov (Ukraine)

2009-07-15

New technology is required for the removal of water and heavy fractions from regular coal tar. Centrifuges offer the best option. Purification of coal tar by means of centrifuges at OAO NLMK permits the production of pitch coke or electrode pitch that complies with current standards.

Gasification of oil sand coke: review

Energy Technology Data Exchange (ETDEWEB)

Furimsky, E. [IMAF Group, Ottawa, ON (Canada)

1998-08-01

The production of synthetic crude from the tar sands in Western Canada has been steadily increasing. Most of the delayed coke produced by Suncor is combusted on site, whereas all fluid coke produced by Syncrude is stockpiled.The database on the chemical and physical properties of the oil sand coke, including the composition and fusion properties of the mineral matter, has been established. The reactivity of the coke was determined by oxygen chemisorption, fixed bed and fluid bed bench scale gasification and pilot plant gasification. The reactivity of the oil sand coke for gasification is rather low and comparable to high rank coals, such as anthracite. Slurrability tests revealed that a solid concentration in water, approaching 70 wt%, can be achieved. Gasification is the front runner among clean technologies for the conversion of carbonaceous solids to useful products. Several commercial gasifiers are available to cover the wide range of severity. Because of the low reactivity of oil sands coke, high severity conditions are required to achieve high gasification conversion. Such conditions can be attained in entrained bed gasifiers. Gasifiers employing both dry and slurry feeding systems are suitable. A high efficiency, low SO{sub x} and NO{sub x} emissions, as well as a low solid waste production are among the key advantages of the gasification technology compared with thecompeting technologies. Commercial gasification of oil sands coke is delayed because of the availability of natural gas on the site of the upgrading plants. Potential for the transportation of the oil sand coke to USA for electricity generation using the integrated gasification combined-cycle (IGCC) technology was evaluated. 27 refs., 17 figs., 9 tabs.

Coal tar pitch. Interrelations between properties and utilization of coal tar pitch

Energy Technology Data Exchange (ETDEWEB)

Collin, G; Koehler, H [Ruetgerswerke A.G., Duisburg (Germany, F.R.)

1977-06-01

Coal tar pitch is won as a highly aromatic, thermoplastic residue by destillating coal tar. In this paper the structure as well as the chemical and physical data of this pitch are introduced. In addition to this the actual as well as possible applications are indicated. For example, the pitch can be used for the production of binders, e.g. for electrodes and road construction as well as in combination with plastics for the production of insulating material and corrosion protection material.

Coal tar: past, present and future

Energy Technology Data Exchange (ETDEWEB)

Thami, G.P.; Sarkar, R. [Government Medical College & Hospital, Chandigarh (India). Dept. of Dermatology & Venerology

2002-03-01

Crude coal tar has been used in the treatment of dermatoses for many decades. In the last few years its use has been limited to skin diseases such as psoriasis and chronic dermatitis. Newer topical modalities for psoriasis are being used increasingly for treatment, but have failed to replace crude coal tar as a first-line treatment of psoriasis. The authors review the pharmacology, chemistry and use of crude coal tar in order to reappraise its role as a therapeutic agent in dermatology.

Distillation of tar and tar fractions in the presence of surface-active coke

Energy Technology Data Exchange (ETDEWEB)

Jaeppelt, A; Klaus, J

1943-01-01

The tar obtained by low-temperature carbonization of Upper Silesian gas coke and fractions from this tar were distilled in the presence of different grades of coke dust with varying surface activity; the coke had been activated by steam in the course of its production by low-temperature carbonization. The surface activity of the coke dusts was measured by determining the heat of wetting with C/sub 6/H/sub 6/. Tar and coke dust, both anhydrous, were mixed in a kneading machine in such proportions that the capillaries of the dust were saturated and enough ''externally'' bound tar was present to permit briquetting. The briquets were distilled without cracking and with steam as heating medium. The yield and quality of the distillate depended on the magnitude of the internal surface of the coke dust used; a mixture of a very active coke from brown coal and tar yielded a distillate with Conradson carbon residue of 1.34 percent, asphalt content 6.1 percent and eta/sub 20/ 5.4/sup 0/ E. as compared with C residue of 10.95 percent, asphalt content 33.5 percent and eta/sub 20/ 123.6/sup 0/ E. of the distillate obtained in the absence of surface-active coke. Even higher-boiling fractions can be improved by this treatment, although it is preferable to use oils with an initial boiling point below 300/sup 0/. The ratio of oil to adsorbent is not critical, but better results were obtained with higher percentages of added coke dust. The process in its present form is not suited for the conversion of crude creosote to useful phenols.

Flash hydropyrolysis of bituminous coal . III. Research on flash hydropyrolysis tar

Energy Technology Data Exchange (ETDEWEB)

Dong, M.; Zhu, Z.; He, Y.; Ding, N.; Tang, L. [East China University of Science and Technology, Shanghai (China)

2000-02-01

Tar sample obtained by flash hydropyrolysis (FHP) from Dongshen coal at high pressure entrained reactor was investigated. An effect of flash hydropyrolysis temperature on the main components in tar was studied and the quality of the tar was compared with high temperature coke oven tar. The results showed that: the yields of liquid hydrocarbon in FHP tar were more than 15%, which is twofold of that in coke oven tar; the FHP tar has high oil fraction and low pitch; high phenol components and pure condensed polycyclic aromatic hydrocarbon, and low aliphatic hydrocarbon. The components of the FHP tar were simpler than that of high temperature coke oven tar. Therefore, FHP has improved the quantity and quality of tar. 11 refs., 3 figs., 5 tabs.

Physical and performance properties of coal tar urethanes - pipe

International Nuclear Information System (INIS)

Hickney, J.; Hendry, M.

1984-01-01

The purpose of this paper is to review certain physical properties of coal tar extended urethane coatings designed specifically for use in the pipe coatings market. The blend of coal tar and urethane resins provides a novel finished product with properties cumulatively inherent in its constituents. Typically, coal tar and coal tar pitch offer exceptional water resistance and cathodic alkali resistance when blended with other resins. An example is the standard coal tar epoxies used for many years in the marine markets for shipbottoms

Characterization of acid tar waste from benzol purification | Danha ...

African Journals Online (AJOL)

The use of concentrated sulphuric acid to purify benzene, toluene and xylene produces acidic waste known as acid tar. The characterization of the acid tar to determine the composition and physical properties to device a way to use the waste was done. There were three acid tars two from benzene (B acid tar), toluene and ...

Pacific Northwest Laboratory Annual Report for 1979 to the DOE Assistant Secretary for Environment Part 4 Physical Sciences

Energy Technology Data Exchange (ETDEWEB)

Nielsen, J. M.

1980-02-01

This volume contains 63 articles on physical science activities in diverse areas, including coal, fission, radiation physics, geothermal resource development, oil shale and tar sand research, and multitechnology development.

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

Science.gov (United States)

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

Cancer fear over coal tar products

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-01-01

Discusses a report by Dutch researchers which suggests that the regular use of coal tar shampoos may significantly increase the risk of cancer due to the high levels of polynuclear aromatic hydrocarbons (PAHs) in the products. The PAH exposure of volunteers using a coal tar anti-dandruff shampoo was studied by measuring the amount of hydroxypyrene, a PAH breakdown product in their urine. Volunteers who had used the shampoo excreted high levels of hydroxypyrene the day after exposure. Excretion by the control group using a non-coal tar anti-dandruff shampoo remained constant. 1 ref., 1 fig.

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

Science.gov (United States)

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

Structure and Mechanism of Staphylococcus aureus TarS, the Wall Teichoic Acid β-glycosyltransferase Involved in Methicillin Resistance.

Directory of Open Access Journals (Sweden)

Solmaz Sobhanifar

2016-12-01

Full Text Available In recent years, there has been a growing interest in teichoic acids as targets for antibiotic drug design against major clinical pathogens such as Staphylococcus aureus, reflecting the disquieting increase in antibiotic resistance and the historical success of bacterial cell wall components as drug targets. It is now becoming clear that β-O-GlcNAcylation of S. aureus wall teichoic acids plays a major role in both pathogenicity and antibiotic resistance. Here we present the first structure of S. aureus TarS, the enzyme responsible for polyribitol phosphate β-O-GlcNAcylation. Using a divide and conquer strategy, we obtained crystal structures of various TarS constructs, mapping high resolution overlapping N-terminal and C-terminal structures onto a lower resolution full-length structure that resulted in a high resolution view of the entire enzyme. Using the N-terminal structure that encapsulates the catalytic domain, we furthermore captured several snapshots of TarS, including the native structure, the UDP-GlcNAc donor complex, and the UDP product complex. These structures along with structure-guided mutants allowed us to elucidate various catalytic features and identify key active site residues and catalytic loop rearrangements that provide a valuable platform for anti-MRSA drug design. We furthermore observed for the first time the presence of a trimerization domain composed of stacked carbohydrate binding modules, commonly observed in starch active enzymes, but adapted here for a poly sugar-phosphate glycosyltransferase.

Characterization of Tar Deposits, Extraction and Sorption Properties

Directory of Open Access Journals (Sweden)

Pryszcz Adrian

2016-06-01

Full Text Available The main goal of this paper was to characterize and find a useful solution for the decomposition of tar deposits. For the experimental part, tar deposits, formed by polymerization and condensation reactions, were chosen from a storage tank for tars. At first the initial analyses of tar deposits (elemental, thermogravimetric, and calorimetric analyses were performed. After the characterization, the tar deposits were extracted in the Soxhlet extractor by acetone, toluene, and quinolone and activated with potassium hydroxide. As the final step of this work, the sorption characterization on the 3Flex Surface Characterization Analyzer (Micromeritics was performed. The specific surface area of the samples was evaluated using two methods - a single point measurement at p/p0=0.2 and BET method. Micropore and external surface areas were calculated based on a t-plot analysis (carbon black model.

Preparation of pure phenols from tars

Energy Technology Data Exchange (ETDEWEB)

Meyer, J

1929-06-18

A process is disclosed for preparing pure phenols from brown coal and shale tar, characterized in that the alkaline extract obtained from the tar is oxidized and concurrently the alkaline solution is separated from the existing impurities by heating with steam at high temperature, which finally reaches at least 150/sup 0/C.

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

Science.gov (United States)

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.

New method for the exact determination of phenols in low-temperature tar and tar oils

Energy Technology Data Exchange (ETDEWEB)

Lambris, G; Haferkorn, H

1949-01-01

A 3-gram sample of water-free tar or tar oil containing approximately 50% phenols is dissolved in a mixture of benzene and xylene and a known excess of a 20% KOH solution of known normality saturated with benzene and xylene is added. Weight of the KOH is determined by difference. This mixture is shaken repeatedly in a 300-milliliter separatory funnel. After standing for 0.5 h, the dark or almost black phenolate solution containing the major portion is separated and weighed. Care must be taken to prevent the induction of solids. The phenolate in the residue is extracted with hot water and titrated with 0.2N HCl and 1 ml. Congo red (1:100). If water is present in the tar or tar oil, 100 ml of xylene is added immediately after weighing and the water separated by distillation the weight of which must be determined. Any phenols carried over are dissolved in the small quantity of xylene in the distillate. This quantity is added to the bulk of the xylene. After any remaining phenols are extracted from the tar residue with boiling benzene, the benzene-xylene mixture is treated with KOH as above. The accuracy of the method is estimated to be +-1% as shown by experiments with phenol; o-, m-, and p-cresol; cresol mixture; and pyrocatechol. The weight of the dissolved phenols X is determined by X = c - a + cd/(ab - d) where a = weight of KOH, b = HCl used per gram of KOH, C = weight of major portion of phenolate solution, which is formed by shaking the phenol solution with KOH, d = HCl used for titration of phenolate residue.

Infrared absorption characteristics of hydroxyl groups in coal tars

Energy Technology Data Exchange (ETDEWEB)

Cannon, S A; Chu, C J; Hange, R H; Margrave, J L

1987-01-01

Tar evolution was observed over a temperature range of 150-600 C for four coals. Pittsburgh bituminous, Illinois No.6, Rawhide subbituminous, and Texas lignite. Isolation of the evolved tars in a nitrogen matrix at 15 degrees K produced better resolved infrared spectra than those in a coal matrix, thus enhancing structural characterization of the tar molecules. Two distinct hydroxyl functional groups in the tar molecules free of hydrogen bonding were identified for the first time without interference from H/sub 2/O absorptions. These absorptions at 3626.5 cm/sup -1/ have been assigned to phenolic hydroxyls. It is suggested that carboxylic and aliphatic hydroxyl groups do not survive the vaporization process. Tars from Illinois No.6 were found to contain the largest amount of phenolic hydroxyl; Pittsburgh No. 8 tar contains approximately half of that for Illinois No.6 while Rawhide and Texas lignite contain much less phenolic than either of the other coals. 10 references, 6 figures, 1 table.

Sunflower oil in the treatment of hot tar burns.

Science.gov (United States)

Türegün, M; Oztürk, S; Selmanpakoğlu, N

1997-08-01

Hot tar burns compose a unique class of thermal injury, because removal of this highly sticky compound may be very difficult without inflicting additional tissue damage. Early removal of tar facilitates assessment of the burn and improves patient comfort. Although the use of many substances for the painless removal of tar has been described, we used sunflower oil effectively in the treatment of four tar burn patients. This first report describes the practical and successful use of sunflower oil which was easily obtained from the hospital kitchen.

Tar dew point analyser as a tool in biomass gasification

Energy Technology Data Exchange (ETDEWEB)

Vreugdenhil, B.J.; Kuipers, J. [ECN Biomass, Coal and Environmental Research, Petten (Netherlands)

2008-08-15

Application of the Tar Dew point Analyzer (TDA) in different biomass based gasification systems and subsequent gas cleaning setups has been proven feasible. Such systems include BFB gasifiers, CFB gasifier and fixed bed gasifiers, with tar crackers or different scrubbers for tar removal. Tar dew points obtained with the TDA give direct insight in the performance of the gas cleaning section and help prevent any tar related problems due to condensation. The current TDA is capable of measuring tar dew points between -20 to 200C. This manuscript will present results from 4 different gasification setups. The range of measured tar dew points is -7 to 164C with comparable results from the calculated dew points based on the SPA measurements. Further detail will be presented on the differences between TDA and SPA results and explanations will be given for deviations that occurred. Improvements for the TDA regarding future work will be presented.

The catalytic cracking mechanism of lignite pyrolysis char on tar

International Nuclear Information System (INIS)

Lei, Z.; Huibin, H.; Xiangling, S.; Zhenhua, M.; Lei, Z.

2017-01-01

The influence of different pyrolysis conditions for tar catalytic cracking will be analyzed according to the lignite pyrolysis char as catalyst on pyrolytic tar in this paper. The pyrolysis char what is the by-product of the cracking of coal has an abundant of pore structure and it has good catalytic activity. On this basis, making the modified catalyst when the pyrolysis char is activation and loads Fe by impregnation method. The cracking mechanism of lignite pyrolytic tar is explored by applying gas chromatograph to analyze splitting products of tar. The experimental results showed that: (1) The effect of tar cracking as the pyrolysis temperature, the heating rate, the volatilization of pyrolysis char and particle size increasing is better and better. The effect of the catalytic and cracking of lignite pyrolysis char in tar is best when the heating rate, the pyrolysis temperature, the volatiles of pyrolysis char, particle size is in specific conditions.(2) The activation of pyrolysis char can improve the catalytic effect of pyrolysis char on the tar cracking. But it reduces the effect of the tar cracking when the pyrolysis char is activation loading Fe. (author)

Low-temperature tar and oil: properties and applications

Energy Technology Data Exchange (ETDEWEB)

Heinze, R

1942-01-01

In Germany the value of low-temperature tar is largely dependent on its fuel fractions; these vary with the coal and the method of carbonization (external heating or recirculated gases). Brown-coal tars can be processed by distillation, cracking under pressure, hydrogenation under pressure (largest volume of tar is processed by this method) and by solvent extraction, with EtOH, SO/sub 2/, or phenol. Each of these processes is discussed in detail. In the pressure-hydrogenation process, 1.25 kilogram of brown-coal tar yields approximately 1 kilogram of gasoline with an octane number of 60 to 70. Low-temperature tars from bituminous coals can be hydrogenated readily but are not well adapted to solvent extraction. Attempts should be made to produce tar approximating the desired characteristics for fuel directly from the carbonizing apparatus. For laboratory carbonization tests, an approximation to results secured by externally heated retorts is secured by using an insert consisting of a series of perforated trays in the 200-gram Fischer aluminum retort; this reduces the capacity to 100 gram. Fractional condensation is used to separate heavy oil, middle oil, and liquor; low-boiling products are condensed at -20/sup 0/ by solid CO/sub 2/.

Chemical-composition studies of low-temperature-carbonization coal tar

Energy Technology Data Exchange (ETDEWEB)

Edel' shtein, N G; Lanin, V A

1955-01-01

Pintsch-oven low-temperature tar was separated into its constituents by conventional methods, and the average of 2 results was neutral asphaltenes 12.56, basic asphaltenes 2.61, acid asphaltenes 18.82, phenols 13.23, bases 2.31, neutral oil 17.66, crystalline paraffins 7.34, silica-gel tars (I) (benzene extract) 15.40, I (acetone extract) 2.47, carbenes 0.45, and carbides and dust 1.44%. The low-temperature-tar asphaltenes and tars differ from shale-oil tars by being lower in C and higher in H, with a considerably higher C:H ratio. Their specific gravity is somewhat higher, and they are cyclic in structure. The asphaltenes and silica-gel tars of coal tar and shale oil were hydrogenated, molecular weights d/sub 4//sup 20/ and n/sub 4//sup 20/ of the separated compounds were determined, and empirical formulas of the hydrogenated compounds calculated. The neutral oil was separated into saturated, intermediate (iodine number 23), unsaturated (iodine number 51), a small quantity of a mixture of unsaturated and aromatic hydrocarbons, and 44.9% aromatic hydrocarbons. While naphthenes seem to be predominantly present in the neutral-oil fraction of shale oil, aromatic hydrocarbons are predominant in coal oil.

Process of transforming tars, etc

Energy Technology Data Exchange (ETDEWEB)

1929-04-11

A process is described for treating tars obtained by carbonization, at high or low temperature, of coals, lignites, shales, and other carbonaceous materials or fractions of these tars, for obtaining products of greater value, consisting of polymerizing or saturating the unstable hydrocarbons in the presence of catalyzers by the progressing action particularly of halogenated metals, such as titanium tetrachloride, iron chloride, etc. and applying a known process of recovery, the disclosed process leading to an important reduction of final losses.

Mineral oils, tars. [British patent

Energy Technology Data Exchange (ETDEWEB)

O' Brien, A M; Handmarch, E

1933-08-11

Hydrocarbon materials such as mineral oils and tars from coal, shale, lignite, or peat are freed from phenols and like oxy-bodies by heating under pressure in a closed vessel to a temperature and for a time sufficient to effect reduction of the oxy-bodies, and then removing the water formed by the reaction. 350/sup 0/ to 400/sup 0/C. for 30 to 60 minutes is suitable. Any wax-like constituents are converted to liquids of lower viscosity and settling point. The product may be fractionated to give light oils and a residue of aviation Diesel fuel. In an example, oil from the low-temperature distillation of coal and having a tar acid content of 30 per cent is treated in a tubular converter at 380/sup 0/C. and 400 lb. per sq. in for 40 min., and the benzine toluol, and xylol distilled; the residue has a tar acid content of only 7.6 per cent.

Oil sands tax expenditures

International Nuclear Information System (INIS)

Ketchum, K; Lavigne, R.; Plummer, R.

2001-01-01

The oil sands are a strategic Canadian resource for which federal and provincial governments provide financial incentives to develop and exploit. This report describes the Oil Sands Tax Expenditure Model (OSTEM) developed to estimate the size of the federal income tax expenditure attributed to the oil sands industry. Tax expenditures are tax concessions which are used as alternatives to direct government spending for achieving government policy objectives. The OSTEM was developed within the business Income Tax Division of Canada's Department of Finance. Data inputs for the model were obtained from oil sands developers and Natural Resources Canada. OSTEM calculates annual revenues, royalties and federal taxes at project levels using project-level projections of capital investment, operating expenses and production. OSTEM calculates tax expenditures by comparing taxes paid under different tax regimes. The model also estimates the foregone revenue as a percentage of capital investment. Total tax expenditures associated with investment in the oil sands are projected to total $820 million for the period from 1986 to 2030, representing 4.6 per cent of the total investment. 10 refs., 2 tabs., 7 figs

Reaction Mechanism of Tar Evolution in Biomass Steam Gasification for Hydrogen Production

International Nuclear Information System (INIS)

Shingo Katayama; Masahiro Suzuki; Atsushi Tsutsumi

2006-01-01

Reaction mechanism of tar evolution in steam gasification of biomass was investigated with a continuous cross-flow moving bed type differential reactor, in which tar and gases can be fractionated according to reaction time. We estimated that time profile of tar and gas evolution in the gasification of cellulose, xylan, and lignin, and compared it with experimental product time profile of real biomass gasification. The experimental tar evolution rate is different from estimated tar evolution rate. The estimated tar evolution rate has a peak at 20 s. On the other hand, the experimental tar evolution rate at 20 s is little, and tar at initial stage includes more water-soluble and water-insoluble compounds. It can be concluded that in the real biomass steam gasification the evolution of tar from cellulose and lignin component was found to be precipitated by that from hemi-cellulose component. (authors)

DECOMPOSITION OF TARS IN MICROWAVE PLASMA – PRELIMINARY RESULTS

Directory of Open Access Journals (Sweden)

Mateusz Wnukowski

2014-07-01

Full Text Available The paper refers to the main problem connected with biomass gasification - a presence of tar in a product gas. This paper presents preliminary results of tar decomposition in a microwave plasma reactor. It gives a basic insight into the construction and work of the plasma reactor. During the experiment, researches were carried out on toluene as a tar surrogate. As a carrier gas for toluene and as a plasma agent, nitrogen was used. Flow rates of the gases and the microwave generator’s power were constant during the whole experiment. Results of the experiment showed that the decomposition process of toluene was effective because the decomposition efficiency attained above 95%. The main products of tar decomposition were light hydrocarbons and soot. The article also gives plans for further research in a matter of tar removal from the product gas.

Recovery of very viscous lubricating oils from shale-tar, etc

Energy Technology Data Exchange (ETDEWEB)

Erdmann, E

1918-01-22

A process is disclosed for the recovery of very viscous lubricating oils from brown-coal tar and shale tar, consisting in driving off from the crude tar or the tar freed from volatile constituents after removal of paraffin by precipitation with a volatile solvent such as acetone or one of its homologs, the light oils more or less completely with superheated steam from about 200 to 250/sup 0/C without any outside heating over a free flame.

VAPOR PRESSURES AND HEATS OF VAPORIZATION OF PRIMARY COAL TARS

Energy Technology Data Exchange (ETDEWEB)

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 which 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.

Microstructure and properties of lignite tar and pitch. Part II

Energy Technology Data Exchange (ETDEWEB)

Walther, H

1954-01-01

Photomicrographs reveal the presence of crystalline wax which affects the working properties in lignite tars and pitch. The crystals are large needles after slow cooling and small after rapid cooling. The crystals are paraffinic in character. All samples were nonhomogeneous. Thus the properties of lignite tar and pitch are varied by the source of the lignite and history of the specimen, neither softening point nor dropping point seems to satisfactorily characterize these tars. The samples exhibit thixotropic behavior characteristic of a structural viscosity and show hysteresis loops on varying the working rate. The variations have hindered use of lignite tars and pitches except where solubility in a solvent such as coal tar oil can be used to advantage.

Catalytic destruction of tar in biomass derived producer gas

International Nuclear Information System (INIS)

Zhang Ruiqin; Brown, Robert C.; Suby, Andrew; Cummer, Keith

2004-01-01

The purpose of this study is to investigate catalytic destruction of tar formed during gasification of biomass, with the goal of improving the quality of the producer gas. This work focuses on nickel based catalysts treated with alkali in an effort to promote steam gasification of the coke that deposits on catalyst surfaces. A tar conversion system consisting of a guard bed and catalytic reactor was designed to treat the producer gas from an air blown, fluidized bed biomass gasifier. The guard bed used dolomite to crack the heavy tars. The catalytic reactor was used to evaluate three commercial steam reforming catalysts. These were the ICI46-1 catalyst from Imperial Chemical Industry and Z409 and RZ409 catalysts from Qilu Petrochemical Corp. in China. A 0.5-3 l/min slipstream from a 5 tpd biomass gasifier was used to test the tar conversion system. Gas and tar were sampled before and after the tar conversion system to evaluate the effectiveness of the system. Changes in gas composition as functions of catalytic bed temperature, space velocity and steam/TOC (total organic carbon) ratio are presented. Structural changes in the catalysts during the tests are also described

Characterization of acid tars

Energy Technology Data Exchange (ETDEWEB)

Leonard, Sunday A., E-mail: sunday.leonard@ucl.ac.uk [Department of Civil Environmental and Geomatic Engineering, University College London, Chadwick Building, Gower Street, London, WC1E 6BT (United Kingdom); Stegemann, Julia A. [Department of Civil Environmental and Geomatic Engineering, University College London, Chadwick Building, Gower Street, London, WC1E 6BT (United Kingdom); Roy, Amitava [J. Bennett Johnston, Sr., Centre for Advance Microstructures and Devices (CAMD), 6980 Jefferson Highway, Louisiana State University, Baton Rouge, LA, 70806 (United States)

2010-03-15

Acid tars from the processing of petroleum and petrochemicals using sulfuric acid were characterized by gas chromatography/mass spectrometry (GC/MS), inductively coupled plasma/optical emission spectrometry (ICP/OES), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectrometry, and scanning electron microscopy/energy dispersive X-ray (SEM/EDX) micro-analysis. Leaching of contaminants from the acid tars in 48 h batch tests with distilled water at a liquid-to-solid ratio 10:1 was also studied. GC/MS results show that the samples contained aliphatic hydrocarbons, cyclic hydrocarbons, up to 12 of the 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs), and numerous other organic groups, including organic acids (sulfonic acids, carboxylic acids and aromatic acids), phenyl, nitrile, amide, furans, thiophenes, pyrroles, and phthalates, many of which are toxic. Metals analysis shows that Pb was present in significant concentration. DSC results show different transition peaks in the studied samples, demonstrating their complexity and variability. FTIR analysis further confirmed the presence of the organic groups detected by GC/MS. The SEM/EDX micro-analysis results provided insight on the surface characteristics of the samples and show that contaminants distribution was heterogeneous. The results provide useful data on the composition, complexity, and variability of acid tars; information which hitherto have been scarce in public domain.

Characterization of acid tars

International Nuclear Information System (INIS)

Leonard, Sunday A.; Stegemann, Julia A.; Roy, Amitava

2010-01-01

Acid tars from the processing of petroleum and petrochemicals using sulfuric acid were characterized by gas chromatography/mass spectrometry (GC/MS), inductively coupled plasma/optical emission spectrometry (ICP/OES), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectrometry, and scanning electron microscopy/energy dispersive X-ray (SEM/EDX) micro-analysis. Leaching of contaminants from the acid tars in 48 h batch tests with distilled water at a liquid-to-solid ratio 10:1 was also studied. GC/MS results show that the samples contained aliphatic hydrocarbons, cyclic hydrocarbons, up to 12 of the 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs), and numerous other organic groups, including organic acids (sulfonic acids, carboxylic acids and aromatic acids), phenyl, nitrile, amide, furans, thiophenes, pyrroles, and phthalates, many of which are toxic. Metals analysis shows that Pb was present in significant concentration. DSC results show different transition peaks in the studied samples, demonstrating their complexity and variability. FTIR analysis further confirmed the presence of the organic groups detected by GC/MS. The SEM/EDX micro-analysis results provided insight on the surface characteristics of the samples and show that contaminants distribution was heterogeneous. The results provide useful data on the composition, complexity, and variability of acid tars; information which hitherto have been scarce in public domain.

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

Science.gov (United States)

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.

Application of organic geochemistry to coastal tar residues from central California

Energy Technology Data Exchange (ETDEWEB)

Kvenvolden, K.A.; Rosenbauer, R.J.; Hostettler, F.D.; Lorenson, T.D.

2000-01-01

Tar residues are common on the Monterey Bay National Marine Sanctuary. These coastal tar residues have been washed ashore and usually occur on headlands near the high-tide line. In this study, 18 coastal tar residues were collected and analyzed to determine their carbon isotopic compositions and values of selected biomarker ratios. All of the residues have very heavy ({sup 13}C-enriched) carbon isotopic compositions spanning a narrow range ({delta}{sup 13}C = {minus}22.2 to {minus}23.4{per{underscore}thousand}), and 28,30-bisnorhopane is present in all samples. These same geochemical characteristics are found in Monterey Formation oils from which the coastal tar residues were likely derived. These coastal residues could result from natural seeps or from accidental spills. Statistically the coastal tar residues can be organized into three groups, each of which may represent different spill or seep events. Seven samples of potential local representative sources for the tar residues were examined, but none could account for the coastal tars.

Final Safety Assessment of Coal Tar as Used in Cosmetics

Energy Technology Data Exchange (ETDEWEB)

NONE

2008-07-01

Coal Tar is a semisolid by-product obtained in the destructive distillation of bituminous coal, which functions in cosmetic products as a cosmetic biocide and denaturant-antidandruff agent is also listed as a function, but this is considered an over-the-counter (OTC) drug use. In 2002, Coal Tar was reported to the Food and Drug Administration (FDA) to be used in four formulations, all of which appear to be OTC drug products. Coal Tar is monographed by the FDA as Category I (safe and effective) OTC drug ingredient for use in the treatment of dandruff, seborrhoea, and psoriasis. Coal Tar is absorbed through the skin of animals and humans and is systemically distributed. 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.

UTILIZATION OF AQUEOUS-TAR CONDENSATES FORMED DURING GASIFICATION

Directory of Open Access Journals (Sweden)

Anna Kwiecińska

2016-11-01

Full Text Available Gasification of solid fuels is an alternative process for energy production using conventional and renewable fuels. Apart from desired compounds, i.e. carbon oxide, hydrogen and methane, the produced gas contains complex organic (tars and inorganic (carbonizate, ammonia contaminants. Those substances, together with water vapor, condensate during cooling of the process gas, what results in the formation of aqueous-tar condensate, which requires proper methods of utilization. The management of this stream is crucial for commercialization and application of the gasification technology. In the paper the treatment of aqueous-tar condensates formed during biomass gasification process is discussed. The removal of tars from the stream was based on their spontaneous separation. The aqueous stream was subjected to ultrafiltration operated at different pressures. Such a treatment configuration enabled to obtain highly concentrated retentate, which could be recycled to the gasifier, and filtrate, which could be subjected to further treatment.

Evaluation of lignite tar

Energy Technology Data Exchange (ETDEWEB)

Gossedin, A

1946-01-01

Tar from the low-temperature (450/sup 0/) carbonization of lignite from Bouches-du-Rhone was hydrogenated in the presence of a catalyst based on MoS/sub 2/ with a 3:1 H:N mixture. Processing (at 470/sup 0/ and 400 atmospheres) for maximum production of gasoline yielded 86 wt % of a product of boiling 55 to 186/sup 0/ and motor octane number 75. An alternative is to hydrogenate with a view to producing solvents and lubricants. For this purpose the tar was separated by distillation (at 20 millimeters, cutting at 220/sup 0/) into two fractions of equal volume. On hydrogenation (at 300/sup 0/ and 400 atmospheres) the light part yields a gasoline H/sub 2/O-soluble cut, a highly aromatic solvent fraction, a heavier cut (280/sup 0/ to 320/sup 0/) suitable as a plasticizer, and a phenol fraction. The heavier part of the tar is hydrogenated (at 380/sup 0/ and 400 atmospheres) to give spindle oil and lubricating oil of medium eta (11.2 centistokes at 98.2/sup 0/), moderate eta index (64), good pour point (-7/sup 0/), and good oxidizing characteristics. The overall yield of products from the two portions is 86.9% (gasoline and solvent 32, light phenols 9.7, spindle oil 14.2, medium lubricating oil 25.7, wax, 5.3%).

Modeling Tar Recirculation in Biomass Fluidized Bed Gasification

NARCIS (Netherlands)

Heineken, Wolfram; De la Cuesta de Cal, Daniel; Zobel, Nico

2016-01-01

A biomass gasification model is proposed and applied to investigate the benefits of tar recirculation within a gasification plant. In the model, tar is represented by the four species phenol, toluene, naphthalene, and benzene. The model is spatially one-dimensional, assuming plug flow for the

Alberta Oil Sands Equity annual report, 1992-93. Partnership and progress in Alberta's oil sands development

International Nuclear Information System (INIS)

1993-01-01

Alberta Oil Sands Equity (AOSE) manages the Alberta government's equity investments in oil sands and heavy oil projects. AOSE is a 16.74% participant in the Syncrude Project, a 10% participant in the OSLO (Other Six Leases Operation) Commercial Project and the OSLO New Ventures project, and a 24.17% participant in the Lloydminster Bi-Provincial Upgrader. Syncrude produces ca 12% of Canadian crude oil requirements, and AOSE's share yielded $44 million profit for 1992/93, slightly higher than the the $43.3 million the previous year. The OSLO Commercial Project is a proposed commercial oil sands plant with a mine site and extraction plant to be located north of Fort McMurray, and an upgrading facility to be situated north of Edmonton. Work on this project was suspended in early 1992. The OSLO New Ventures project will handle the exploration and development of the remaining five oil sands leases plus the southern portion of Lease 31. As of March 31, 1993, the project owners were considering a commercial demonstration project utilizing dredging and cold-water extraction processes. Two of the owners are unable to provide funding and discussions are under way to resolve the matter and move the program forward. The Lloydminster Bi-Provincial Upgrader opened Noveber 20, 1992, and production has reached 41,000 bbl/d, or 89% of design capacity. The upgrader will increase the value of heavy crude oil and thereby increase its demand. 5 figs., 3 tabs

Composition of coal tar from pyrolysis and hydropyrolysis of Shenmu coal macerals

Energy Technology Data Exchange (ETDEWEB)

Sun, Q.; Li, W.; Chen, H.; Li, B. [Shandong Academy of Sciences, Jinan (China)

2005-08-15

To understand the relationship of the tar compositions and the coal macerals, the tars obtained from the pyrolysis and hydropyrolysis of Shenmu coal macerals in a fixed-bed reactor were analysed using GC-MS. And the effects of petrographic component, atmosphere and pressure on the yield of aromatic hydrocarbon, phenols, hydrocarbons, oxygen-containing heterocycle and PAHs were systematically investigated. The results show that there is great difference in the composition and the relative content of long chain hydrocarbons, aromatic hydrocarbons, phenols, oxygen-containing heterocycle and PAHs in tars from vitrinite and inertinite pyrolysis. Vitrinite tar contains high content of hydrocarbon with long chain, and inertinite tar contains high content of aromatic hydrocarbons, phenols, oxygen-containing heterocycle and PAHs. It suggests that vitrinite has lower aromaticity and longer chain in its structure than inertinite, which is in well agreement with the result from {sup 13}C NMR and FT-IR test. The tar yield of hydropyrolysis is higher than that of pyrolysis. With increasing the hydrogen pressure, the yield of tar increases greatly. The content of phenols and naphthalene in vitrinite tar form hydropyrolysis under 0.1 MPa is much lower than that form pyrolysis, while that of inertinite tar changes a little. The difference of tar compositions and relative content during pyrolysis and hydropyrolysis reflects the effect of hydrogenation and hydrocracking reactions and the structure characteristics of the macerals. 12 refs., 3 figs.

48 CFR Appendix to Part 1252 - Tar Matrix

Science.gov (United States)

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...

Low-temperature tar from bituminous coal and its further treatment

Energy Technology Data Exchange (ETDEWEB)

Hansen, C J

1950-01-01

High-temperature carbonization of bituminous coal yields only 3 to 4 percent tar, as compared with 8 to 10 percent or even more for low-temperature carbonization. The yield of phenols is 20 to 30 times as great from the low-temperature tar. Five conditions that must be met by a satisfactory low-temperature carbonization process are listed. The only method that satisfies all of these conditions is the Brennstoff-Technik (BT) process, in which iron retorts with movable walls are used. One disadvantage of most of the other processes is the high-pitch content of the tar. These tars are processed further to a neutral oil and a phenol-containing oil which are good diesel fuels with high-cetane numbers; the neutral oil can be fractionated to give oils of high-, medium-, and low-cetane number. Attempts to fractionate the tar oil by solvents have not proved commercially useful. However, the tar can be diluted with low-temperature light oil and phenols extracted with NaOH solution without distillation. Some difficulty is found, owing to the simultaneous extraction of viscous resins and other products that are readily removed from the phenols by distillation.

Alberta Oil Sands Equity annual report, 1991-92. Partnership and progress in Alberta's oil sands development

International Nuclear Information System (INIS)

1992-01-01

Alberta Oil Sands Equity (AOSE) manages the Alberta government's equity investments in oil sands and heavy oil projects. AOSE is a 16.74% participant in the Syncrude Project, a 10% participant in the OSLO (Other Six Leases Operation) Commercial Project and the OSLO New Ventures project, and a 24.17% participant in the Lloydminster Bi-Provincial Upgrader. Syncrude produces over 11% of Canadian crude oil requirements, and AOSE's share yielded $43.3 million profit for 1991/92, down significantly from the $82.1 million the previous year due to lower oil prices. The OSLO Commercial Project is a proposed commercial oil sands plant with a mine site and extraction plant to be located north of Fort McMurray, and an upgrading facility to be situated north of Edmonton. Work on this project was suspended in early 1992. The OSLO New Ventures project will handle the exploration and development of the remaining five oil sands leases plus the southern portion of Lease 31. As of March 31, 1992, the project owners were considering a commercial demonstration project utilizing dredging and cold-water extraction processes. Two of the owners are unable to provide funding and discussions are under way to resolve the matter and move the program forward. The Lloydminster Bi-Provincial Upgrader was nearly 90% complete in March 1992 and full startup is expected in November 1992; engineering work was completed in March 1991. The upgrader will increase the value of heavy crude oil and thereby increase its demand. 4 figs., 4 tabs

Evaluation of Gravimetric Tar Determination in Particle Samples

DEFF Research Database (Denmark)

Hindsgaul, Claus; Henriksen, Ulrik B.; Bentzen, Jens Dall

2000-01-01

A comparison of tar determination of particles from a down-draft gasifier using soxhlet extractions (with anisole, dichloromethane and acetone) and pyrolysis of the particles.......A comparison of tar determination of particles from a down-draft gasifier using soxhlet extractions (with anisole, dichloromethane and acetone) and pyrolysis of the particles....

Research investigations in oil shale, tar sand, coal research, advanced exploratory process technology, and advanced fuels research: Volume 1 -- Base program. Final report, October 1986--September 1993

Energy Technology Data Exchange (ETDEWEB)

Smith, V.E.

1994-05-01

Numerous studies have been conducted in five principal areas: oil shale, tar sand, underground coal gasification, advanced process technology, and advanced fuels research. In subsequent years, underground coal gasification was broadened to be coal research, under which several research activities were conducted that related to coal processing. The most significant change occurred in 1989 when the agreement was redefined as a Base Program and a Jointly Sponsored Research Program (JSRP). Investigations were conducted under the Base Program to determine the physical and chemical properties of materials suitable for conversion to liquid and gaseous fuels, to test and evaluate processes and innovative concepts for such conversions, to monitor and determine environmental impacts related to development of commercial-sized operations, and to evaluate methods for mitigation of potential environmental impacts. This report is divided into two volumes: Volume 1 consists of 28 summaries that describe the principal research efforts conducted under the Base Program in five topic areas. Volume 2 describes tasks performed within the JSRP. Research conducted under this agreement has resulted in technology transfer of a variety of energy-related research information. A listing of related publications and presentations is given at the end of each research topic summary. More specific and detailed information is provided in the topical reports referenced in the related publications listings.

Experimental comparison of biomass chars with other catalysts for tar reduction

NARCIS (Netherlands)

Abu El-Rub, Ziad; Bramer, Eduard A.; Brem, Gerrit

2008-01-01

In this paper the potential of using biomass char as a catalyst for tar reduction is discussed. Biomass char is compared with other known catalysts used for tar conversion. Model tar compounds, phenol and naphthalene, were used to test char and other catalysts. Tests were carried out in a fixed bed

Coal-tar based pavement sealant toxicity to freshwater macroinvertebrates

International Nuclear Information System (INIS)

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

2010-01-01

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, and 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. - Coal-tar pavement sealants degrade stream invertebrate communities.

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

Science.gov (United States)

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...

Corrosion test by low-temperature coal tar

Energy Technology Data Exchange (ETDEWEB)

Ando, S; Yamamoto, S

1952-01-01

Corrosive actions of various fractions of low-temperature coal tar against mild steel or Cr 13-steel were compared at their boiling states. Corrosions became severe when the boiling points exceeded 240/sup 0/. The acidic fractions were more corrosive. In all instances, corrosion was excessive at the beginning of immersion testing and then gradually became mild; boiling accelerated the corrosion. Cr 13-steel was corrosion-resistant to low-temperature coal-tar fractions.

Effect of water addition in a microwave assisted thermal cracking of biomass tar models

International Nuclear Information System (INIS)

Warsita, Aris; Al-attab, K.A.; Zainal, Z.A.

2017-01-01

Highlights: • Effective tar thermal treatment with water addition using microwave is proposed. • The reactor temperature of 1200 °C can be reached quickly at bed height 120 mm. • The optimum water to tar ratio W/T was 0.3 for tar models. • Temperature greatly effect tar removal at various W/T rates. - Abstract: 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 in removing tar from producer gas. A question arises as to the possibility of enhancing the removal mechanism by adding water into the reactor. Toluene and naphthalene were used as tar models in the present study with N_2 as the carrier gas followed by the use of simulated producer gas. Thermal treatment with various amount of water was added at temperatures in the range of 800–1200 °C. The tar removal efficiency obtained 95.83% at the optimum temperature of 1200 °C for naphthalene in for toluene 96.32% at 1050 °C at 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.

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

Science.gov (United States)

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.

Occupational coal tar dermatitis

Energy Technology Data Exchange (ETDEWEB)

Conde-Salazar, L; Guimaraens, D; Romero, L V; Gonzalez, M A

1987-04-01

The paper describes the allergic reaction to coal tar of a man handling it in a factory. The reaction appeared in the form of eczema on his trunk, arms and legs, but his hands were not affected as he had been wearing gloves. 1 ref.

179 Extraction of Coal-tar Pitch by Supercritical Carbon Dioxide ...

African Journals Online (AJOL)

Meyer

Several extractions of coal-tar pitch were performed using supercritical fluid ..... pressure and temperature, unlike exhaustive extraction, which involves a change in ... mechanism that is operative on extracting coal-tar pitch components with.

Contact sensitivity to newsprint: a rare manifestation of coal tar allergy

Energy Technology Data Exchange (ETDEWEB)

Illchyshyn, A; Cartwright, P H; Smith, A G

1987-07-01

Contact dermatitis due to coal tar is infrequently reported in spite of the fact that it consists of a mixture of 10,000 constituents, and is still often used to treat both eczema and psoriasis. Discusses patient with coal tar sensitivity in whom the source of exacerbation of her dermatitis is shown to be newsprint, a common product containing coal tar-derived material. 6 refs.

Coal tar phototoxicity: characteristics of the smarting reaction

International Nuclear Information System (INIS)

Diette, K.M.; Gange, R.W.; Stern, R.S.; Arndt, K.A.; Parrish, J.A.

1985-01-01

The properties and ultraviolet exposure parameters of tar smarts were examined in an effort to elucidate the mechanisms involved. It was show that irradiation with 1 minimal smarting dose (MSD) of UVA immediately following tar removal lowered the MSD for 6 h, demonstrated by subsequent challenge with UVA. Following 3 MSDs this memory effect was demonstrable for 24 h. The smarting reaction was area dependent--smaller areas of exposure require higher doses of UVA to induce smarting. Smarting followed reciprocity over a 6-fold range of irradiances (2-12.5 mW/cm2) but higher irradiances required higher doses of UVA, perhaps due to a delay in the recognition and reporting of smarting. The smarting reaction and delayed erythema due to UVA and tar were equally blocked by sunscreen

Coal-tar based pavement sealant toxicity to freshwater macroinvertebrates

Energy Technology Data Exchange (ETDEWEB)

Bryer, P.J.; Scoggins, M.; McClintock, N.L. [Lamar University, Beaumont, TX (United States). Dept. of Biology

2010-05-15

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.

Chemical and physical characteristics of tar samples from selected Manufactured Gas Plant (MGP) sites

International Nuclear Information System (INIS)

Ripp, J.; Taylor, B.; Mauro, D.; Young, M.

1993-05-01

A multiyear, multidisciplinary project concerning the toxicity of former Manufactured Gas Plant (MGP) tarry residues was initiated by EPRI under the Environmental Behavior of Organic Substances (EBOS) Program. This report concerns one portion of that work -- the collection and chemical characterization of tar samples from several former MGP sites. META Environmental, Inc. and Atlantic Environmental Services, Inc. were contracted by EPRI to collect several samples of tarry residues from former MGP sites with varied historical gas production processes and from several parts of the country. The eight tars collected during this program were physically very different. Some tars were fluid and easily pumped from existing wells, while other tars were thicker, semi-solid, or solid. Although care was taken to collect only tar, the nature of the residues at several sites made it impossible not to collect other material, such as soil, gravel, and plant matter. After the samples were collected, they were analyzed for 37 organic compounds, 8 metals, and cyanide. In addition, elemental analysis was performed on the tar samples for carbon, hydrogen, oxygen, sulfur and nitrogen content and several physical/chemical properties were determined for each tar. The tars were mixed together in different batches and distributed to researchers for use in animal toxicity studies. The results of this work show that, although the tars were produced from different processes and stored in different manners, they had some chemical similarities. All of the tars, with the exception of one unusual solid tar, contained similar relative abundances of polycyclic aromatic hydrocarbons (PAHs)

Thermodynamic analysis of tar reforming through auto-thermal reforming process

Energy Technology Data Exchange (ETDEWEB)

Nurhadi, N., E-mail: nurhadi@tekmira.esdm.go.id; Diniyati, Dahlia; Efendi, M. Ade Andriansyah [R& D Centre for Mineral and Coal Technology, Jln. Jend.Sudirman no. 623, Bandung. Telp. 022-6030483 (Malaysia); Istadi, I. [Department of Chemical Engineering, Diponegoro University, Jln. Jl. Prof. Soedarto, SH, Semarang (Malaysia)

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 most 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.

Pelagic tar and plastic in the Gulf of Alaska and Bering Sea: 1975

Energy Technology Data Exchange (ETDEWEB)

Shaw, D G

1977-07-01

Seventy-one tows of 740 m/sup 2/ each were made in search of pelagic tar and plastics in the Gulf of Alaska and Bering Sea during the period October 1974 to October 1975. Tar was observed on nine occasions while plastics were found six times. The arithmetic mean value of tar abundance, 3.3 x 10/sup -3/ mg/m/sup 2/, is considerably lower than most other oceanic areas for which values have been reported. Gas chromatographic analysis of this tar indicates that it is more extensively weathered than tar from the north Atlantic. An estimate of the abundance of tar lumps too small to be sampled by net tows is made based on the assumption that there are equal weights of particles in logarithmetically equal size intervals. The abundance of pelagic plastics is also low.

Extraction of low-temperature tar by various alcohols

Energy Technology Data Exchange (ETDEWEB)

Hara, N; Osawa, M; Azuma, H

1948-01-01

MeOH was the most effective of the alcohols tested (MeOH to pentanol) in extracting acid components from low-temperature tar. The optimum concentrations of MeOH were 70 to 80% for 1 extraction and 70 to 75% for repeated or continuous extractions when the solvent-tar ratio was 1:1. By 2 to 3 extractions neutral oil could be separated in about 90% yield including > 3% acidic oil.

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

Science.gov (United States)

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.

Investing for the future : Athabasca Oil Sands Trust 1998 annual report

International Nuclear Information System (INIS)

1999-01-01

The Athabasca Oil Sand Trust was created in 1995 when a subsidiary of the Trust, Athabasca Oil Sands Investment Inc., acquired Alberta's 11.74 per cent working interest in the Syncrude Project, which is a joint venture involved in the mining and upgrading of bitumen from the Athabasca oil sands. The Trust is a closed-end investment trust which was created to provide an opportunity for direct public investment in Syncrude and oil sands development in northern Alberta. Syncrude, produced a record 76.7 million barrels of Syncrude Sweet Blend (SSB), and shipped its one billionth barrel on April 16, 1998. Another key achievement in 1998 was the investment the Syncrude Joint Venture Partners of almost half a billion dollars to maintain Syncrude's operations and pursue the Business Plan growth targets outlined in last year's report. By aggressively pursuing this capital investment program despite the current low oil prices, the Syncrude Joint Venture Partners expect to double SSB production to 155 million barrels per year by 2007. The Athabasca Trust's share of these capital expenditures to fuel the projected growth in production is about $ 70 million this year and the next. The report provides operating statistics on production, financial highlights and consolidated balance sheets for 1998, including operating expenditures, capital expenditures, and the usual notes to the consolidated financial statement. 10 tabs., 2 figs

Dermal uptake of polycyclic aromatic hydrocarbons after hairwash with coal-tar shampoo

Energy Technology Data Exchange (ETDEWEB)

Schooten, F.-J. van; Moonen, E.J.C.; Rhijnsburger, E.; Agen, B. van; Thijssen, H.H.W.; Kleinjans, J.C.S. [University of Limburg, Maastricht (Netherlands). Dept. of Health Risk Analysis and Toxicology

1994-11-26

Describes an experiment to assess the dermal uptake of polycyclic aromatic hydrocarbons (PAHs) after hairwashing with coal tar antidandruff shampoo. The urinary excretion of 1-hydroxypyrene (1-OH-P), a PAH metabolile was used to assess internal dose of PAH. A single use of coal tar shampoo resulted in increased 1-OH-P excretion in all members of the experimental group compared with the control group using a non-coal tar antidandruff shampoo. It is suggested that repeated use of coal tar shampoo would result in a high internal dose of carcinogenic PAH. 5 refs., 1 fig.

Iron-based materials as tar cracking catalyst in waste gasification

Energy Technology Data Exchange (ETDEWEB)

Nordgreen, Thomas

2011-07-01

The treatment of municipal solid waste (MSW) in Sweden has changed during the past decades due to national legislation and European Union directives. The former landfills have more or less been abandoned in favour of material recycling and waste incineration. On a yearly basis approximately 2.2 million tonnes waste are incinerated in Sweden with heat recovery and to some extent also with electricity generation, though at a low efficiency. It is desirable to alter this utilisation and instead employ MSW as fuel in a fluid bed gasification process. Then electrical energy may be produced at a much higher efficiency. However, MSW contain about 1 % chlorine in the form of ordinary table salt (NaCl) from food scraps. This implies that the tar cracking catalyst, dolomite, which is normally employed in gasification, will suffer from poisoning if applied under such conditions. Then the tar cracking capacity will be reduced or vanish completely with time. Consequently, an alternative catalyst, more resistant to chlorine, is needed. Preliminary research at KTH has indicated that iron in its metallic state may possess tar cracking ability. With this information at hand and participating in the project 'Energy from Waste' an experimental campaign was launched. Numerous experiments were conducted using iron as tar cracking catalyst. First iron sinter pellets from LKAB were employed. They were reduced in situ with a stream of hydrogen before they were applied. Later iron-based granules from Hoeganaes AB were tested. These materials were delivered in the metallic state. In all tests the KTH atmospheric fluidised bed gasifier with a secondary catalytic reactor housing the catalytic material was deployed. Mostly, the applied fuel was birch. The results show that metallic iron possesses an intrinsic ability, almost in the range of dolomite, to crack tars. Calculations indicate that iron may be more resistant to chlorine than dolomite. The exploration of metallic iron

Secondary reactions of tar during thermochemical biomass conversion[Dissertation 14341

Energy Technology Data Exchange (ETDEWEB)

Morf, P.O.

2001-07-01

This dissertation submitted to the Swiss Federal Institute of Technology in Zurich presents and discusses the results obtained during the examination of the processes involved in the formation and conversion of tar in biomass gasification plant. Details are given on the laboratory reactor system used to provide separated tar production and conversion for the purposes of the experiments carried out. The results of analyses made of the tar and the gaseous products obtained after its conversion at various temperatures are presented. The development of kinetic models using the results of the experiments that were carried out is described. The results of the experiments and modelling are compared with the corresponding results obtained using a full-scale down-draft, fixed-bed gasifier. The author is of the opinion that the reaction conditions found in full-scale gasifiers can be well simulated using heterogeneous tar conversion experiments using the lab reactor system.

Tar loads on Omani beaches

International Nuclear Information System (INIS)

Badawy, M.I.; Al-Harthy, F.T.

1991-01-01

Owing to Oman's geographic position and long coastal line, the coastal areas of Oman are particularly vulnerable to oil pollution from normal tanker operations, illegal discharges, and accidental spills as well as local sources of oil input. UNEP carried out a survey on the coasts of Oman to determine the major sources of oil pollution and concluded that the major shoreline pollution problems in Oman arose from operational discharges of oil from passing vessels traffic. The oil, because of the high sea and air temperatures in the area, was subjected to relatively high rates of evaporation and photo-oxidation and tended to arrive at the coast as heavy petroleum particulate residues (tar balls). The aim of the present study was to measure the loads of tar balls in Omani coastal areas and to identify the source of oil pollutants on beaches

Decomposition of tar in gas from updraft gasifier by thermal cracking

DEFF Research Database (Denmark)

Brandt, Peder; Henriksen, Ulrik Birk

2000-01-01

Continuing earlier work with tar reduction by partial oxidation of pyrolysis gas [1] thermal cracking has been evaluated as a gas cleaning process. The work has been focusing on cleaning gas from updraft gasifiers, and the long term purpose is to develop a tar cleaning unit based on thermal...... cracking. An experimental set-up has been built, in which a flow of contaminated gas can be heated up to 1290°C in a reactor made of pure Al2O3. Four measurements were made. Three with gas from a pyrolysis unit simulating updraft gasifier, and one with gas from an updraft gasifier. Cracking temperatures...... was 1200, 1250 and 1290°C, and the residence time at this temperature was 0.5 second. The measurements show that at the selected residence time of 0.5 second, the gas flow in a thermal tar cracking unit has to be heated to at least 1250°C to achieve sufficient tar cleaning. At 1290°C, a tar content as low...

Athabasca--special report No. 2, sand behavior key to operation size

Energy Technology Data Exchange (ETDEWEB)

Daly, W J

1966-09-01

Before production of the crude oil from the Athabasca tar sands could be initiated, a feasibility and economic study based on field test work was made. It was concluded that the project was technically feasible and a plant could be constructed for approximately $137 million, but that the engineering design must be preceded by a field test program, laboratory work, and by ground surveys. A test program, using the hot water recovery process and sized to handle 3 tons of sand per hour, was begun in Oct. 1963. As the test program proceeded, the unit was frequently renovated as capacity was increased from 3 tons to finally 10 tons per hour. Included in the tests was the determination of the effect that raw bitumen pools (indicated by the government coring program) would have on production operations. It was determined that no problems would arise from this situation because no such pools could be found and were considered not to be in existence. The test model was successful in clearly illustrating the principles to use in the overall layout, which is approximately 50% complete.

Reuse of waste cutting sand at Lawrence Livermore National Laboratory

International Nuclear Information System (INIS)

Mathews, S.; Wilson, K.

1998-01-01

Lawrence Livermore National Laboratory (LLNL) examined the waste stream from a water jet cutting operation, to evaluate the possible reuse of waste garnet sand. The sand is a cutting agent used to shape a variety of materials, including metals. Nearly 70,000 pounds of waste sand is generated annually by the cutting operation. The Environmental Protection Department evaluated two potential reuses for the spent garnet sand: backfill in utility trenches; and as a concrete constituent. In both applications, garnet waste would replace the sand formerly purchased by LLNL for these purposes. Findings supported the reuse of waste garnet sand in concrete, but disqualified its proposed application as trench backfill. Waste sand stabilized in a concrete matrix appeared to present no metals-leaching hazard; however, unconsolidated sand in trenches could potentially leach metals in concentrations high enough to threaten ground water quality. A technical report submitted to the San Francisco Bay Regional Water Quality Control Board was reviewed and accepted by that body. Reuse of waste garnet cutting sand as a constituent in concrete poured to form walkways and patios at LLNL was approved

Monitoring of tar contents in gases. Final report

Energy Technology Data Exchange (ETDEWEB)

Petersen, Finn [ChimneyLab Europe ApS, Hadsten (Denmark); Houmann Jakobsen, H. [BioSynergi Proces ApS, Hoersholm (Denmark)

2012-08-15

The purpose of this project is to develop and test a relative cheap and simple online tar measuring method, which can monitor the tar content in product gas from thermal gasification. The measuring principle is absorption of tar from sample gas in Isopropanol (IPA), and measuring on this solution by UV-spectrophotometer. Continuous sampling of tar containing producer gas turned out to be a larger problem than earlier foreseen. The best solution was decided to be sampling with higher flows, and afterwards cleaning the IPA in activated carbon. The ambitions for continuous sampling had to be decreased to 1 week, where the IPA and the activated carbon is contaminated by tar and has to be replaced. However this requires larger amounts of IPA and activated carbon. For IPA the weekly consumption was 12-15 Litres and for activated carbon 10 Litres. The whole analyzer unit turned out to be more complex than first projected, mainly because of the increased amounts of IPA. The best mist filter, with respect to pressure drop, efficiency and retention time is a combination of glass wool and quarts wool. The unit has been tested on gas; 20 kW pellets burner for 116 hours. Harbooere updraft gasifier for 519 hours. Skive fluid bed gasifier for 879 hours. There have during the project period been several simple practical problems such as bubbles in the IPA, increasing pressure drop over the activated carbon bed, dropout of UV data acquisition program and increasing baseline. The principle showed from the beginning some good results, with the limitation of 1 week continuous operation, but at the 5. period in Skive the baseline was increasing all the time, and it was not possible to solve this problem. (LN)

Modelling the low-tar BIG gasification concept[Biomass Integrated gasification

Energy Technology Data Exchange (ETDEWEB)

Andersen, Lars; Elmegaard, B.; Qvale, B.; Henriksen, Ulrrik [Technical univ. of Denmark (Denmark); Bentzen, J.D.; Hummelshoej, R. [COWI A/S (Denmark)

2007-07-01

A low-tar, high-efficient biomass gasification concept for medium- to large-scale power plants has been designed. The concept is named 'Low-Tar BIG' (BIG = Biomass Integrated Gasification). The concept is based on separate pyrolysis and gasification units. The volatile gases from the pyrolysis (containing tar) are partially oxidised in a separate chamber, and hereby the tar content is dramatically reduced. Thus, the investment, and running cost of a gas cleaning system can be reduced, and the reliability can be increased. Both pyrolysis and gasification chamber are bubbling fluid beds, fluidised with steam. For moist fuels, the gasifier can be integrated with a steam drying process, where the produced steam is used in the pyrolysis/gasification chamber. In this paper, mathematical models and results from initial tests of a laboratory Low-Tar BIG gasifier are presented. Two types of models are presented: 1. The gasifier-dryer applied in different power plant systems: Gas engine, Simple cycle gas turbine, Recuperated gas turbine and Integrated Gasification and Combined Cycle (IGCC). The paper determines the differences in efficiency of these systems and shows that the gasifier will be applicable for very different fuels with different moisture contents, depending on the system. 2. A thermodynamic Low-Tar BIG model. This model is based on mass and heat balance between four reactors: Pyrolysis, partial oxidation, gasification, gas-solid mixer. The paper describes the results from this study and compares the results to actual laboratory tests. The study shows, that the Low-Tar BIG process can use very wet fuels (up to 65-70% moist) and still produce heat and power with a remarkable high electric efficiency. Hereby the process offers the unique combination of large scale gasification and low-cost gas cleaning and use of low-cost fuels which very likely is the necessary combination that will lead to a breakthrough of gasification technology. (au)

Structural and dynamic characterization of the upper part of the HIV-1 cTAR DNA hairpin

OpenAIRE

Zargarian, Loussin?; Kanevsky, Igor; Bazzi, Ali; Boynard, Jonathan; Chaminade, Fran?oise; Foss?, Philippe; Mauffret, Olivier

2009-01-01

First strand transfer is essential for HIV-1 reverse transcription. During this step, the TAR RNA hairpin anneals to the cTAR DNA hairpin; this annealing reaction is promoted by the nucleocapsid protein and involves an initial loop?loop interaction between the apical loops of TAR and cTAR. Using NMR and probing methods, we investigated the structural and dynamic properties of the top half of the cTAR DNA (mini-cTAR). We show that the upper stem located between the apical and the internal loop...

The separate effects of tar and nicotine on the cigarette smoking manoeuvre

International Nuclear Information System (INIS)

Woodman, G.; Newman, S.P.; Paiva, D.; Clarke, S.W.

1987-01-01

The separate effects of tar and nicotine on the cigarette smoking manoeuvre were investigated. Each of ten asymptomatic habitual smokers smoked three different commercially available cigarettes in a randomised order. The brands were chosen such that two had the same tar yield (10 mg) and two had the same nicotine yield (1.4 mg). The volume of smoke inhaled into the lungs was measured by tracing the smoke with the inert gas 81 Kr m . Puffing indices were recorded using an electronic smoking analyser and flowhead/cigarette holder. There was no difference in the total volume of smoke puffed from each of the cigarette brands. With cigarettes of the samme tar level, the total inhaled smoke volume was lower with the higher nicotine cigarette (P<0.05): by contrast, with cigarettes of the same nicotine level, the toal inhaled smoke volume was lower with the lower tar cigarette (P<0.02). Tar and nicotine appear to exercise independent control over the volume of smoke inhaled. (author)

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

Science.gov (United States)

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... (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...

Gasification of municipal solid waste in a downdraft gasifier: Analysis of tar formation

Directory of Open Access Journals (Sweden)

Tabitha Geoffrey Etutu

2016-04-01

Full Text Available In this study, municipal solid waste (MSW from a dumpsite was converted into refuse derived fuel (RDF and used as feedstock for an air-blown gasification process. The gasification process was conducted in a 10 kg.hr -1 downdraft gasifier at different air flow rates of 300, 350, 400, 450 and 550 NL.min1 at atmospheric pressure in order to investigate the quantity and quality of tar formed. It was shown that the increase in the air flow rate from 300 NL.min1 to 550 NL.min1 led to an increase in the oxidation temperature from 719°C to 870°C and an increase in the reduction temperature from 585°C to 750°C, respectively. Tar was reduced from 15 g.Nm3 to 4.7 g.Nm3 respectively. Heavy tar compounds (>C17 e.g. pyrene and phenathrene, decreased with the increase in the light tar compounds (tar reduction through a tar cracking process.

Recovery of very viscous lubricating oils from shale-tar, etc

Energy Technology Data Exchange (ETDEWEB)

Erdmann, E

1919-09-10

Modification of the process covered by German Patent 335,190 for recovering very viscous lubricating oils, consisting, in place of brown-coal tar, deparafinned peat tar being subjected to the treatment with superheated steam from about 200 to 250/sup 0/C or to heating in vacuum at a temperature below 250/sup 0/C.

Technological changes illustrated by the coal tar and tar dye industry; Die Wandlung der Technik am Beispiel der Steinkohlenteer- und Teerfarben-Chemie

Energy Technology Data Exchange (ETDEWEB)

Collin, G. [Deutsche Gesellschaft fuer Chemisches Apparatewesen, Chemische Technik und Biotechnologie e.V. (DECHEMA), Frankfurt am Main (Germany)

2001-05-01

Coal tar was detected in the 17th century in laboratory experiments based on empirical knowledge. In the 18th century industrial revolution, coal tar was an undesired by-product of iron production and coking plants. It was first used in the 19th century for impregnating railway sleepers. Later developments in atomic theory, new chemical symbols and organic element analysis provided the basis for discovering and chemical characterisation of coal tar constituents. Laboratory experiments with these tar constituents resulted in the first synthetic dyes, the postulation of tetravalent carbon and the resulting structural theory in organic chemistry for systematic synthesis of many tar dyes to substitute natural dyes in the textile industry. The technical application of these syntheses was part 2 of the industrial revolution and the foundation of the chemical industry in Germany, which developed rapidly in the 2nd half of the 19th century. Tar dye chemistry has made a significant contribution to Germany's economic growth and the change from an agricultural to an industrialized country. [German] Die Entdeckung des Steinkohlenteers im 17. Jahrhundert basiert auf durch Erfahrungswissen gepraegten Laboratoriumsexperimenten. Im Verlauf der 'Industriellen Revolution' des 18. Jahrhunderts ist der Steinkohlenteer zunaechst ein laestiges Abfallprodukt der Eisengewinnung im Kokshochofen und der Leuchtgasherstellung durch Kohlenverkokung. Erste technische Applikation finden Steinkohlenteeroele im 19. Jahrhundert durch den Eisenbahnbau zur Langzeit-Konservierung der dafuer benoetigten Holzschwellen. Die wissenschaftlichen Erfkenntnisse zur Atomtheorie, eine neue chemische Zeichensprache und die organische Elementaranalyse werden Voraussetzungen zur Entdeckung und chemischen Charakterisierung der Hauptinhaltsstoffe des Steinkohlenteers. Laboratoriumsexperimente mit den entdeckten Teerinhaltsstoffen fuehren zur Erfindung der ersten synthetischen Farbstoffe, die

Shaft-retort for treating waste materials, like washery waste, bituminous shale, oil-bearing sands and the like

Energy Technology Data Exchange (ETDEWEB)

Koppers, H

1916-10-29

A shaft-retort for converting waste materials, like washery waste, bituminous shale, oil-bearing sands, brown coal and non-coking mineral coal to oil and tar by supplying heat through the shaft wall formed of an iron-sheet to the material, which is forced through a feeding member perforated for the removal of gases and vapors, and moved downward in a thin layer on the shaft wall; that is characterized by the fact that the iron heating sheet is made rotatable for the purpose of equalizing overheating of itself and the material to be treated.

Inhaled smoke volume and puff indices with cigarettes of different tar and nicotine levels

International Nuclear Information System (INIS)

Woodman, G.; Newman, S.P.; Pavia, D.; Clarke, S.W.

1987-01-01

Ten asymptomatic smokers each smoked a low, low-to-middle and a middle tar cigarette with approximately the same tar-to-nicotine ratio, in a randomised order. The inhaled smoke volume was measured by tracing the smoke with the inert gas 81 Kr m . Puffing indices were recorded using an electronic smoking analyser and flowhead/cigarette holder. Throughout the study neither the mean inhaled smoke volume per puff nor the total inhaled smoke volume per cigarette changed significantly; however, the mean and total puff volumes were largest with the low tar cigarette and decreased with the higher tar brands. Puff volume was related to puff work (r s =0.83,P s =0.10,P>0.1). It is concluded that when switched between brands with the same tar-to-nicotine ratio, smokers increase their puff volumes with a lower tar cigarette but do not change the volume of smoke inhaled. Puff work and puff resistance were significantly correlated (r s =0.45,P<0.02). (author)

Analysis of low-temperature tar fractions

Energy Technology Data Exchange (ETDEWEB)

Kikkawa, S; Yamada, F

1952-01-01

A preliminary comparative study was made on the applicability of the methods commonly used for the type analysis of petroleum products to the low-temperature tar fractions. The usability of chromatography was also studied.

Restoring sand shinnery oak prairies with herbicide and grazing in New Mexico

Science.gov (United States)

Zavaleta, Jennifer C.; Haukos, David A.; Grisham, Blake A.; Boal, Clint W.; Dixon, Charles

2016-01-01

Sand shinnery oak (Quercus havardii) prairies are increasingly disappearing and increasingly degraded in the Southern High Plains of Texas and New Mexico. Restoring and managing sand shinnery oak prairie can support biodiversity, specific species of conservation concern, and livestock production. We measured vegetation response to four treatment combinations of herbicide (tebuthiuron applied at 0.60 kg/ha) and moderate-intensity grazing (50% removal of annual herbaceous production) over a 10-year period in a sand shinnery oak prairie of eastern New Mexico. We compared the annual vegetation response to the historical climax plant community (HCPC) as outlined by the U.S. Department of Agriculture Ecological Site Description. From 2 to 10 years postapplication, tebuthiuron-treated plots had reduced shrub cover with twice as much forb and grass cover as untreated plots. Tebuthiuron-treated plots, regardless of the presence of grazing, most frequently met HCPC. Tebuthiuron and moderate-intensity grazing increased vegetation heterogeneity and, based on comparison of the HCPC, successfully restored sand shinnery oak prairie to a vegetation composition similar to presettlement.

Acid Tar Lagoons: Management and Recovery

Science.gov (United States)

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

Assessment of ground-water contamination by coal-tar derivatives, St. Louis Park area, Minnesota

Science.gov (United States)

Hult, M.F.

1984-01-01

Operation of a coal-tar distillation and wood-preserving facility in St. Louis Park, Minnesota, during 1918-72 contaminated ground water with coal-tar derivatives and inorganic chemicals. Coal-tar derivatives entered the groundwater system through three major paths: (1) Spills and drippings that percolated to the water table, (2) surface runoff and plant process water that was discharged to wetlands south of the former plant site, and (3) movement of coal tar directly into bedrock aquifers through a multiaquifer well on the site.

Simulation of Trajectories of Tar Ball Transport to the Goa Coast

Digital Repository Service at National Institute of Oceanography (India)

Suneel, V.; Vethamony, P.; VinodKumar, K.; Babu, M.T.; Prasad, V.S.R.

Arrival of tar balls to the Goa coast during pre- and southwest monsoon seasons has been a regular phenomenon in the past few years. In one such event, we observed tar ball deposits along the Goa coast during August 2010, April 2011 and May 2011...

The Legend of Hot Tar or Pitch as a Defensive Weapon

DEFF Research Database (Denmark)

Atzbach, Rainer

2015-01-01

research. In reality, this way of fighting can only be seen as a legend, i.e. a story with only a relative truth at its core. This paper will examine the origin of this historical tradition and its archaeological and architectural sources. The chemical and physical properties of tar pitch and its...... production and use during the Middle Ages will be discussed with special focus on the application of tar pitch as an ingredient in medieval and post-medieval thermal weapons (especially Greek Fire, the firebomb and the fire arrow). The punishment of tarring and feathering will also be considered...

Ensamblajes urbanos: la TAR y el examen de la ciudad

Directory of Open Access Journals (Sweden)

Ignacio Farías

2011-03-01

Full Text Available Este artículo presenta nuevas perspectivas de investigación y desafíos analíticos que la teoría del actor-red (TAR abre para los estudios urbanos. En primer lugar, se revisan cómo los principios de relacionalidad híbrida y asociatividad plana de la TAR están siendo adoptados en los estudios urbanos para ampliar simétricamente la ecología urbana a no-humanos e impugnar concepciones escalares del espacio y economías urbanas. A continuación, se propone que la TAR trae consigo un desafío más fundamental relativo a la concepción de la ciudad como objeto de estudio. Mientras su comprensión habitual como objeto espacial, entidad político-económica y/o forma sociocultural subraya su carácter singular, estable y delimitado, la TAR permite pensar la ciudad como un objeto múltiple y decentrado. La noción de ensamblajes urbanos se introduce entonces para dar cuenta de la circulación y devenir de la ciudad en múltiples redes híbridas y translocales. El artículo concluye sopesando algunas de las consecuencias de este exámen de la ciudad, especialmente el reposicionamiento del problema de la complejidad, urbana en este caso, como punto, si no de partida, entonces al menos de llegada para la TAR.

Copyrolysis of coal with coke-oven gas. III. Analysis of tar

Energy Technology Data Exchange (ETDEWEB)

Liao, H.; Sun, C.; Li, B.; Liu, Z. [Chinese Academy of Sciences, Taiyuan (China). State Key Laboratory of Coal Conversion, Institute of Coal Chemistry

1998-02-01

Tars from copyrolysis of Xianfeng lignite with coke-oven gas (COG) at different pressures (0.1-5 MPa) and heating rates (5-25{degree}C/min) to a final temperature of 650{degree}C were analyzed and compared with hydropyrolysis under the same H{sub 2} partial pressure. The results indicated that high contents of BTX, PCX and naphthalene were found in the tar from copyrolysis of Xianfeng lignite with COG. Pressure and heating rate have important effects on tar yields and the contents of BTX, PCX and naphthalene in oil. Increasing pressure and decreasing heating rate enhance the tar yields and result in high yields of BTX and PCX. When compared with hydropyrolysis under the same H{sub 2} partial pressure, the tar yield increases by 1.2 times and the yields of BTX, PCX and naphthalene by about 1.6, 1.3 and 1.6 times, respectively. At the same total pressure (3MPa), the yields of BTX and naphthalene from copyrolysis are equal to those from hydropyrolysis. The results reveal that other components in COG, such as methane, carbon monoxide etc., are of importance for pyrolysis behaviour of coal under COG and improvement of oil qualities. 5 refs., 5 figs., 2 tabs.

Relevance of carbon structure to formation of tar and liquid alkane during coal pyrolysis

International Nuclear Information System (INIS)

Liu, Peng; Le, Jiawei; Wang, Lanlan; Pan, Tieying; Lu, Xilan; Zhang, Dexiang

2016-01-01

Highlights: • Curve-fitting method was used to quantify the accurate contents of structural carbon. • Effect of carbon structure in coal with different rank on formation of pyrolysis tar was studied. • Numerical interrelation between carbon types in coal structure and tar yield is elaborated. • Effect of carbon structure on formation of liquid alkane during coal pyrolysis is discussed. - Abstract: The relevance of carbon structure to formation of tar and liquid alkane during coal pyrolysis were discussed extensively. The pyrolysis tests were carried out in a tube reactor at 873 K and keep 15 min. The carbon distribution in coals was investigated by solid state "1"3C nuclear magnetic resonance (N.M.R.). The curve-fitting method was used to quantify the accurate contents of structural carbon. The alkanes in coal tar were analyzed by Gas Chromatograph–Mass Spectrometer (GC–MS). The results show that oxygen-linked aromatic carbon decreases with the increasing of coal rank. The aliphatic carbon contents of Huainan (HN) coal are 44.20%, the highest among the four coals. The carbon types in coal structure have a significant influence on the formation of tar and liquid alkane. The coal tar yields are related to the aliphatic substituted aromatic carbon, CH_2/CH_3 ratio and oxygen-linked carbon in coal so that the increasing order of tar yield is Inner Mongolia lignite (IM, 6.30 wt.%) < Sinkiang coal (SK, 7.55 wt.%) < Shenmu coal (SM, 12.84 wt.%) < HN (16.29 wt.%). The highest contents of oxygen-linked aromatic carbon in IM lead to phenolic compound of 41.06% in IM-tar. The contents of alkane in SM-tar are the highest because the appropriate CH_2/CH_3 ratio and the highest aliphatic side chains on aromatic rings in SM leading to generate aliphatic hydrocarbon with medium molecular weight easily. The mechanism on formation of tar and liquid alkane plays an important role in guiding the industrialization of pyrolysis-based poly-generation producing tar with high

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

International Nuclear Information System (INIS)

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

2013-01-01

Highlights: ► This is first fingerprinting study in India on identification of source of tar balls. ► Tar balls were formed from tanker-wash spills and they resemble floating tar ball. ► δ 13 C values of Bombay High crude oil and the present tar balls do not match. ► Compound specific stable carbon isotope analysis confirmed the source of tar balls. ► Source is confirmed as the South East Asian Crude Oil and not the Bombay High crude. -- Abstract: 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 (δ 13 C) 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

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

Science.gov (United States)

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...

A review of the primary measures for tar elimination in biomass gasification processes

International Nuclear Information System (INIS)

Devi, Lopamudra; Ptasinski, K.J.; Janssen, F.J.J.G.

2003-01-01

Tar formation is one of the major problems to deal with during biomass gasification. Tar condenses at reduced temperature, thus blocking and fouling process equipments such as engines and turbines. Considerable efforts have been directed on tar removal from fuel gas. Tar removal technologies can broadly be divided into two approaches; hot gas cleaning after the gasifier (secondary methods), and treatments inside the gasifier (primary methods). Although secondary methods are proven to be effective, treatments inside the gasifier are gaining much attention as these may eliminate the need for downstream cleanup. In primary treatment, the gasifier is optimized to produce a fuel gas with minimum tar concentration. The different approaches of primary treatment are (a) proper selection of operating parameters, (b) use of bed additive/catalyst, and (c) gasifier modifications. The operating parameters such as temperature, gasifying agent, equivalence ratio, residence time, etc. play an important role in formation and decomposition of tar. There is a potential of using some active bed additives such as dolomite, olivine, char, etc. inside the gasifier. Ni-based catalyst are reported to be very effective not only for tar reduction, but also for decreasing the amount of nitrogenous compounds such as ammonia. Also, reactor modification can improve the quality of the product gas. The concepts of two-stage gasification and secondary air injection in the gasifier are of prime importance. Some aspects of primary methods and the research and development in this area are reviewed and cited in the present paper

Solid state 13 C NMR quantitative study of wood tar pitches

International Nuclear Information System (INIS)

Prauchner, Marcos Juliano; Pasa, Vanya Marcia Duarte; Menezes, Sonia Maria Cabral de

1999-01-01

In this work, solid-state 13 C NMR is used with other techniques to characterize Eucalyptus tar pitches and to follow their polymerization reactions. The pitches are the residues of distillation (about 50% m;m) of the tar generated in Eucalyptus slow pyrolysis for charcoal production in metal industry

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

Science.gov (United States)

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...

Avoiding tar formation in biocoke production from waste biomass

International Nuclear Information System (INIS)

Adrados, A.; De Marco, I.; Lopez-Urionabarrenechea, A.; Solar, J.; Caballero, B.

2015-01-01

This paper focuses in avoiding tar formation and in optimizing pyrolysis gas (maximizing H 2 and CO) in the production of biocoke from waste lignocellulosic biomass. In order to obtain metallurgical grade biochar (biocoke) slow heating rate and high temperature are required. Under such conditions useless pyrolysis liquids, mainly composed of water together with some heavy-sticky tars, are obtained. In order to make biocoke a cost-effective process it is necessary to optimize pyrolysis vapors avoiding tar formation and maximizing the amount and quality of both coke and gases. With this objective, in this work different heating rates (3–20 °C min −1 ) and catalysts (zeolite, Ni/CeO 2 –Al 2 O 3 ) have been tested in a two step pyrolysis process. Olive tree cuttings have been pyrolyzed in a 3.5 L batch reactor at 750 °C and the vapors generated have been thermally and catalytically treated at 900 °C in a second tubular reactor. About 25 wt.% biocoke useful as reducing agent in certain metallurgical processes, ≈57 wt.% gases with near 50 vol.% H 2 , and no tar production has been achieved when a heating rate of 3 °C min −1 and the homemade Ni/CeO 2 –Al 2 O 3 catalyst were used. - Highlights: • Metallurgical grade biochar was obtained by olive waste pyrolysis. • Low heating rates avoid tar formation and increase gas and biochar yields. • Ni/CeO 2 –Al 2 O 3 was better than HZSM5 zeolite for vapor upgrading in a second step. • Ni/CeO 2 –Al 2 O 3 and 3 °C min −1 gave the maximum H 2 , gas and biochar yields

Cancer risk estimation for mixtures of coal tars and benzo(a)pyrene

International Nuclear Information System (INIS)

Gaylor, D.W.; Culp, S.J.; Goldstein, L.S.; Beland, F.A.

2000-01-01

Two-year chronic bioassays were conducted by using B6C3F1 female mice fed several concentrations of two different mixtures of coal tars from manufactured gas waste sites or benzo(a)pyrene (BaP). The purpose of the study was to obtain estimates of cancer potency of coal tar mixtures, by using conventional regulatory methods, for use in manufactured gas waste site remediation. A secondary purpose was to investigate the validity of using the concentration of a single potent carcinogen, in this case benzo(a)pyrene, to estimate the relative risk for a coal tar mixture. The study has shown that BaP dominates the cancer risk when its concentration is greater than 6,300 ppm in the coal tar mixture. In this case the most sensitive tissue site is the forestomach. Using low-dose linear extrapolation, the lifetime cancer risk for humans is estimated to be: Risk -4 (ppm coal tar in total diet) + 240 x 10 -4 (ppm BaP in total diet), based on forestomach tumors. If the BaP concentration in the coal tar mixture is less than 6,300 ppm, the more likely case, then lung tumors provide the largest estimated upper limit of risk, Risk -4 (ppm coal tar in total diet), with no contribution of BaP to lung tumors. The upper limit of the cancer potency (slope factor) for lifetime oral exposure to benzo(a)pyrene is 1.2 x 10 -3 per microg per kg body weight per day from this Good Laboratory Practice (GLP) study compared with the current value of 7.3 x 10 -3 per microg per kg body weight per day listed in the US EPA Integrated Risk Information System

Experimental and theoretical evaluation of the performance of a tar solar water heater

International Nuclear Information System (INIS)

Ammari, H.D.; Nimir, Y.L.

2003-01-01

The paper presents an experimental and theoretical evaluation of the performance of a tar solar water heater and comparison with that of a conventional type collector. The performance of both collectors is assessed under the same conditions. Both of the collectors have the same surface area and are glazed. The conventional type has the water tubes welded to the absorber plate, whereas in the tar type, the tar acts as an absorber plate that covers the water tubes. The theoretical model for each collector type, with the transient effects taken into account, is based on a control volume and a time base in the related energy equations. By considering a small element of the collector in each case, three partial differential equations were developed for each collector and were solved numerically by the Runge-Kutta method of the fifth order. A good agreement was achieved between the numerical and experimental results for both the conventional and tar collectors, indicating the feasibility of employing the theoretical model in the design of flat plate solar collectors. The results also showed that the conventional collector is more efficient than the tar type during most of the daylight, but the tar collector had the added advantage of better conservation of energy in late afternoon and evening

Estimating release of polycyclic aromatic hydrocarbons from coal tar at manufactured-gas plant sites

International Nuclear Information System (INIS)

Loehr, R.C.; Rao, P.S.C.; Lee, L.S.; Okuda, I.

1992-08-01

One component of the EPRI's research on Envirorunental Behavior of Organic Substances (EBOS) consists of developing information and models to predict releases of monocyclic and polycyclic aromatic hydrocarbons (MAHs and PAHs) to groundwater from coal tars and contaminated soils at MGP sites. The results of this report focus primarily on release of PAHs from coal tars. There are at least two approaches to predicting the release of organic chemicals from coal tar to water. The simplest method to estimate aqueous concentrations is to assume that water solubility of a PAH compound released from the tar can be defined by equilibrium precipitation-dissolution reactions. Application of Raoult's law is another method to predict aqueous concentrations, which requires the assumption of ''ideal'' behavior for partitioning of PAHs between the tar and water phases. To evaluate the applicability of these two methods for predicting PAH releases, laboratory experiments were conducted with eight coal tar samples from former MGP sites across the country. Migration of chemicals in the environment and resulting contaminant plumes in groundwater are determined by leachate concentrations of the chemicals. The use of equilibrium precipitation-dissolution reactions will usually result in an overestimation of PAH concentrations in the leachate from a coal tar source, and thus the resulting PAH concentrations in groundwater. Raoult's law appears to be a more accurate approach to predicting the release of several PAHs from coal tars. Furthermore, if nonequilibrium conditions prevail, aqueous-phase PAH concentrations will be even lower than those predicted using Raoult's law

Release of polyaromatic hydrocarbons from coal tar contaminated soils

International Nuclear Information System (INIS)

Priddy, N.D.; Lee, L.S.

1996-01-01

A variety of process wastes generated from manufactured gas production (MGP) have contaminated soils and groundwater at production and disposal sites. Coal tar, consisting of a complex mixture of hydrocarbons present as a nonaqueous phase liquid, makes up a large portion of MGP wastes. Of the compounds in coal tar, polyaromatic hydrocarbons (PAHs) are the major constituents of environmental concern due to their potential mutagenic and carcinogenic hazards. Characterization of the release of PAHs from the waste-soil matrix is essential to quantifying long-term environmental impacts in soils and groundwater. Currently, conservative estimates for the release of PAHs to the groundwater are made assuming equilibrium conditions and using relationships derived from artificially contaminated soils. Preliminary work suggests that aged coal tar contaminated soils have much lower rates of desorption and a greater affinity for retaining organic contaminants. To obtain better estimates of desorption rates, the release of PAHs from a coal tar soil was investigated using a flow-interruption, miscible displacement technique. Methanol/water solutions were employed to enhance PAH concentrations above limits of detection. For each methanol/water solution employed, a series of flow interrupts of varying times was invoked. Release rates from each methanol/water solution were estimated from the increase in concentration with duration of flow interruption. Aqueous-phase release rates were then estimated by extrapolation using a log-linear cosolvency model

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

Science.gov (United States)

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.

Extraction of tar acids with methanol from low-temperature tar

Energy Technology Data Exchange (ETDEWEB)

Funasaka, W; Yokogawa, C; Suga, S

1948-01-01

From 20 grams crude middle oil, boiling at 200/sup 0/ to 250/sup 0/, acid content 40%, tar acids were extracted at 20/sup 0/ to 30/sup 0/ with MeOH for comparison with EtOH, NMe/sub 3/, and ethylene glycol. When 80% MeOH is used, the oil extracted amounts to 61%, including 9% acids, if the ratio of crude oil and solvent is kept at 1:2. EtOH is inferior to MeOH. The properties of the crude oil and the purified oil extracted with 80% MeOH are described.

Tar Removal from Biomass Producer Gas by Using Biochar

DEFF Research Database (Denmark)

Ravenni, Giulia; Henriksen, Ulrik Birk; Ahrenfeldt, Jesper

2017-01-01

The biomass-derived char (biochar) produced in the gasifier as a residue, is a potential solution for removing tars from producer gas. This work investigates the interaction between tar compounds and biochar. Residual biochar from a TwoStage gasifier was tested as bed material in a laboratory setup....... Phenol and naphthalene were chosen as model tars, and entrained in a nitrogen flow. The gaseous stream was sampled before and after the biochar bed to evaluate the extent of conversion. The biochar bed (30g) was tested at 250°C, 500°C and 600°C, with for 3 consecutive hours. The compounds concentration...... in the gas phase was quantified by stable isotope dilution analysis, using Gas Chromatography-Mass Spectrometry (GC-MS). Results showed a significant effect of biochar on the removal of phenol, at all temperatures. Naphthalene was removed less efficiently at higher temperature, and this trend was even more...

Solvent refining of low-temperature tar with liquid ammonia

Energy Technology Data Exchange (ETDEWEB)

Ishida, K

1953-01-01

The middle fractions of low-temperature tar were treated with mixed solutions of H/sub 2/O and liquid NH/sub 3/ at 0/sup 0/ and 20/sup 0/, and with liquid NH/sub 3/ at -10, 0, + 10, and 20/sup 0/, and phase equilibrium between tar acids, neutral oil, and solvents were studied. The distribution ratio ranged from less than 1 to greater than 1 when the solvent contained about 20 percent (by weight) H/sub 2/O. When the solvent contained less than 85 percent (by weight) NH/sub 3/, the yield of extract was small but the purity of phenols in the extracted oil was above 90 percent. Solvent containing about 85 percent NH/sub 3/ (by weight) is considered optimum for separating tar acids from oils. A novel definition is proposed for solvent selectivity as the difference between the concentration of the solute in the extract layer, on a solvent-free basis, and the concentration in the raffinate layer.

A Life Cycle Assessment of Silica Sand: Comparing the Beneficiation Processes

Directory of Open Access Journals (Sweden)

Anamarija Grbeš

2015-12-01

Full Text Available Silica sand or quartz sand is a mineral resource with a wide variety of application; glass industry, construction and foundry are the most common examples thereof. The Republic of Croatia has reserves of 40 million tons of silica sand and a long tradition of surface mining and processing. The average annual production of raw silica sand in Croatia in the period from 2006 to 2011 amounted to 150 thousand tons. This paper presents cradle to gate LCA results of three different types of beneficiation techniques: electrostatic separation; flotation; gravity concentration. The aim of this research is to identify and quantify the environmental impacts of the silica sand production, to learn the range of the impacts for different processing methods, as well as to identify the major contributors and focus for further process design development.

Reef community structure, Sand Island, Oahu HI, (NODC Accession 0000177)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — These reports provide the results of nine years (1990-98) of an annual quantitative monitoring of shallow marine communities inshore of the Sand Island Ocean...

Ukrainian brown-coal tars recovered at low-temperature carbonization with solid heating medium

Energy Technology Data Exchange (ETDEWEB)

Kuznetsov, V I; Govorova, R P; Fadeicheva, A G; Kigel, T B; Chernykh, M K

1955-01-01

Three samples of tar were recovered in the laboratory from brown coals carbonized at 375/sup 0/ to 456/sup 0/ +- 25/sup 0/ in a retort with inner heating by solid circulating medium, namely, semicoke (ratio: 4 or 3:1) first heated to 700/sup 0/. One comparative (parallel) experiment was carried out in a retort with inner heating by inert gases entering the retort at 580/sup 0/ to 600/sup 0/ and leaving it at 115/sup 0/ to 120/sup 0/. The tars that were recovered from the retort with the solid heating medium contained a high percentage of coal dust and moisture, which were separated from the tars in supercentrifuges (15,000 rpm). Four samples of cleaned tars were fractionated in a Cu flask with a 2-ball fractional column. The tars from the retort with the solid-heating medium are characterized by increased yield of the petroleum-ether fraction (16.3 or 19.3%) and decreased yield of the paraffin fraction (15.1 to 21.2%) in comparison with those of tar from the retort with gas heating (5.9% of the petroleum ether fraction and 36.5% of paraffin fraction). The yield of paraffin from the paraffin fraction also decreased from 90.6% to 62.6-74.3%. This result shows that in the first case the carbonized products were cracked to a higher degree than those from the retort with gas heating. In raw phenols recovered from fractions of investigated tars, the yield of the phenol-cresol fraction (182/sup 0/ to 204/sup 0/) decreased from 25.9% to 13.0-18.9%.

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

Energy Technology Data Exchange (ETDEWEB)

Wicakso, Doni Rahmat [Chemical Engineering Department, Faculty of Engineering, Lambung Mangkurat University, Jalan A. Yani KM. 36 Banjarbaru, 70714, South Kalimantan (Indonesia); Chemical Engineering Department, Faculty of Engineering, Gadjah Mada University, Jalan Grafika No. 2 Bulaksumur, Yogyakarta, 55281 (Indonesia); Sutijan; Rochmadi [Chemical Engineering Department, Faculty of Engineering, Gadjah Mada University, Jalan Grafika No. 2 Bulaksumur, Yogyakarta, 55281 (Indonesia); Budiman, Arief, E-mail: abudiman@ugm.ac.id [Chemical Engineering Department, Faculty of Engineering, Gadjah Mada University, Jalan Grafika No. 2 Bulaksumur, Yogyakarta, 55281 (Indonesia); Center for Energy Studies, Gadjah Mada University, Sekip K1A, Yogyakarta, 55281 (Indonesia)

2016-06-03

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 evaporated 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.

Influence green sand system by core sand additions

Directory of Open Access Journals (Sweden)

N. Špirutová

2012-01-01

Full Text Available Today, about two thirds of iron alloys casting (especially for graphitizing alloys of iron are produced into green sand systems with usually organically bonded cores. Separation of core sands from the green sand mixture is very difficult, after pouring. The core sand concentration increase due to circulation of green sand mixture in a closed circulation system. Furthermore in some foundries, core sands have been adding to green sand systems as a replacement for new sands. The goal of this contribution is: “How the green sand systems are influenced by core sands?”This effect is considered by determination of selected technological properties and degree of green sand system re-bonding. From the studies, which have been published yet, there is not consistent opinion on influence of core sand dilution on green sand system properties. In order to simulation of the effect of core sands on the technological properties of green sands, there were applied the most common used technologies of cores production, which are based on bonding with phenolic resin. Core sand concentration added to green sand system, was up to 50 %. Influence of core sand dilution on basic properties of green sand systems was determined by evaluation of basic industrial properties: moisture, green compression strength and splitting strength, wet tensile strength, mixture stability against staling and physical-chemistry properties (pH, conductivity, and loss of ignition. Ratio of active betonite by Methylene blue test was also determined.

Phytotoxicity and Plant Productivity Analysis of Tar-Enriched Biochars

Science.gov (United States)

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.

Carbon materials for syngas conditioning and tar removal

International Nuclear Information System (INIS)

Romero Millán, Lina María; Sierra Vargas, Fabio Emiro

2017-01-01

Within the framework of worldwide energy context, the development of technologies and processes for energy production form renewable and non-conventional sources is a priority. According to this, gasification is an interesting process that converts different kinds of organic materials in fuel gases. The main issue related with this process is the fact that the producer gas contains also contaminants and tars that are undesirable for the gas usage in internal combustion motors or turbines. The present work aims to analyze the actual state of the existing methods to remove tars form gasification fuel gases, emphasizing the use of different kinds of carbon materials. (author)

Process from removing benzine, toluene, etc. , from petroleum residues, coal tar, and shale tar, etc

Energy Technology Data Exchange (ETDEWEB)

Hlawaty, F

1888-08-11

A process is described for the preparation of ligroin and its homologs as well as naphthalene and anthracene consisting in leading superheated water vapor into a mixture of petroleum residues (or mineral coal tar, etc.) heated to about 400/sup 0/C with cellulosic substances as sage shreds, sea grass, or straw, with addition of caustic alkali.

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

Energy Technology Data Exchange (ETDEWEB)

Jack L. Arbiser; Baskaran Govindarajan; Traci E. Battle; Rebecca Lynch; David A. Frank; Masuko Ushio-Fukai; Betsy N. Perry; David F. Stern; G. Tim Bowden; Anquan Liu; Eva Klein; Pawel J. Kolodziejski; N. Tony Eissa; Chowdhury F. Hossain; Dale G. Nagle [Emory University School of Medicine, Atlanta, GA (United States). Department of Dermatology

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 endothelial 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.

Comprehensive database of Manufactured Gas Plant tars. Part C. Heterocyclic and hydroxylated polycyclic aromatic hydrocarbons.

Science.gov (United States)

Gallacher, Christopher; Thomas, Russell; Lord, Richard; Kalin, Robert M; Taylor, Chris

2017-08-15

Coal tars are a mixture of organic and inorganic compounds that were by-products from the manufactured gas and coke making industries. The tar compositions varied depending on many factors such as the temperature of production and the type of retort used. For this reason a comprehensive database of the compounds found in different tar types is of value to understand both how their compositions differ and what potential chemical hazards are present. This study focuses on the heterocyclic and hydroxylated compounds present in a database produced from 16 different tars from five different production processes. Samples of coal tar were extracted using accelerated solvent extraction (ASE) and derivatized post-extraction using N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) with 1% trimethylchlorosilane (TMCS). The derivatized samples were analysed using two-dimensional gas chromatography combined with time-of-flight mass spectrometry (GCxGC/TOFMS). A total of 865 heterocyclic compounds and 359 hydroxylated polycyclic aromatic hydrocarbons (PAHs) were detected in 16 tar samples produced by five different processes. The contents of both heterocyclic and hydroxylated PAHs varied greatly with the production process used, with the heterocyclic compounds giving information about the feedstock used. Of the 359 hydroxylated PAHs detected the majority would not have been be detected without the use of derivatization. Coal tars produced using different production processes and feedstocks yielded tars with significantly different heterocyclic and hydroxylated contents. The concentrations of the individual heterocyclic compounds varied greatly even within the different production processes and provided information about the feedstock used to produce the tars. The hydroxylated PAH content of the samples provided important analytical information that would otherwise not have been obtained without the use of derivatization and GCxGC/TOFMS. Copyright © 2017 John Wiley & Sons, Ltd.

Tar removal from biosyngas in the biomass gasification process. (Liquid + liquid) equilibrium {water + solvent (paraxylene and methyl hexadecanoate) + model molecules of tar (benzene, toluene, phenol)}

International Nuclear Information System (INIS)

Bassil, Georgio; Mokbel, Ilham; Abou Naccoul, Ramy; Stephan, Juliette; Jose, Jacques; Goutaudier, Christelle

2012-01-01

Highlights: ► (Liquid + liquid) equilibria at atmospheric pressure. ► Solubility of benzene (or toluene or phenol) in paraxylene at (303 to 343) K. ► Solubility of benzene (or toluene or phenol) in methyl palmitate or methyl hexadecanoate at (303 to 343) K. ► Correlation of LLE using NRTL model. - Abstract: Tar is generated in the process by the condensation of the gas resulting from biomass gasification. The objective of this work is a contribution to the database on thermodynamic quantity which will be useful at the operation of tar removal from aqueous medium. With this aim, (liquid + liquid) equilibrium of {water + solvent (paraxylene and methyl hexadecanoate) + model molecules of tar (benzene, toluene, phenol)} was studied at temperatures (303.2, 323.2, and 343.2) K. The data obtained were correlated with the non-random two-liquid (NRTL) model.

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

Science.gov (United States)

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.

Changes in active eolian sand at northern Coachella Valley, California

Science.gov (United States)

Katra, Itzhak; Scheidt, Stephen; Lancaster, Nicholas

2009-04-01

Climate variability and rapid urbanization have influenced the sand environments in the northern Coachella Valley throughout the late 20th century. This paper addresses changes in the spatial relationships among different sand deposits at northern Coachella Valley between two recent time periods by using satellite data acquired from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER). The approach employed here, involving multispectral thermal infrared (TIR) data and spectral mixture analysis, has shown that the major sand deposits can be spatially modeled at northern Coachella Valley. The "coarse-grained (quartz-rich) sand" deposit is associated with active eolian sand, and the "mixed sandy soil" and "fine-grained (quartz-rich) sand" deposits are associated with inactive eolian sand. The fractional abundance images showed a significant decrease between 2000 and 2006 in the percentage of active sand in the major depositional area for fluvial sediment, the Whitewater River, but also in two downwind areas: the Whitewater and Willow Hole Reserves. The pattern of the active sand appears to be related to variations in annual precipitation (wet and dry years) and river discharge in the northern Coachella Valley. We suggest here that recent human modifications to the major watercourses that supply sand affect the capability of fluvial deposition areas to restore sediments over time and consequently the responses of the sand transport system to climate change, becoming more sensitive to dry years where areas of active sand may shrink, degrade, and/or stabilize faster. The approach utilized in this study can be advantageous for future monitoring of sand in the northern Coachella Valley for management of these and similar environments.

Longshore sediment transport at Golden Sands (Bulgaria

Directory of Open Access Journals (Sweden)

Hristo Nikolov

2006-09-01

Full Text Available The paper presents the results of studies on the qualitative and quantitative features of the littoral drift at Golden Sands (Bulgaria, carried out jointly by Polish and Bulgarian researchers. The mathematical modelling of physical coastal processes took wave transformation (wave diffraction and refraction; the effects of shoaling and wave breaking and longshore sediment transport into account. The computations were carried out for the mean statistical annual wave climate, determined on the basis of IO BAS wave data, simulated using the WAM method from long-term Black Sea wind data. The results of sediment transport computations clearly show that its direction off the Golden Sands shore is from north to south.

The documentation of tar balls on oiled shorelines : lessons from the New Carissa, Oregon

International Nuclear Information System (INIS)

Owens, E.H.; Zimlicki-Owens, L.M.; Lamarche, A.; Reimer, P.D.; Martin, C.A.

2000-01-01

The New Carissa, carrying approximately 400,000 gallons of fuel oils ran aground on the outer shore of North Spit, in the vicinity of Coos Bay, Oregon, on February 4, 1999. The oil was released directly into the nearshore surf zone. Following the spill, a stretch of approximately 300 km of the coast of Oregon was surveyed and monitored. The need for the documentation of stranded tar balls in the neighbourhood of the spill site prompted the implementation of a long-term observation program. Initially, Shoreline Clean-up and Assessment Technique (SCAT) reporting procedures were required. Heavy oiling was followed by stranded oil taking the form of tar balls. The amount of oil on the shoreline decreased and the SCAT procedures alone were no longer adequate. They provided estimations of oil quantities that were too high and failed to provide any discrimination between amounts of oil observed on the beaches. A new reporting technique called Beach Assessment Reporting was designed to overcome the difficulties and record adequately the character and frequency of stranded tar balls. Maps, tables and histograms of stranded tar ball volumes and concentrations were discussed. Since the data spanned nine orders of magnitude at times, the semi-logarithmic scale time series plots of the concentration of the tar balls was used in order to identify trends. Conventional histograms only identified large values and camouflaged smaller trends in the time series. A direct method for describing tar ball concentrations geographically proved to be the use of weekly maximum tar ball concentration maps by segment. 10 refs., 2 tabs., 9 figs

Comparative assessment of coal tars obtained from 10 former manufactured gas plant sites in the eastern United States

Energy Technology Data Exchange (ETDEWEB)

Brown, D.G.; Gupta, L.; Kim, T.H.; Moo-Young, H.K.; Coleman, A.J. [Lehigh University, Bethlehem, PA (United States). Dept. of Civil & Environmental Engineering

2006-11-15

A comparative analysis was performed on eleven coal tars obtained from former manufactured gas plant sites in the eastern United States. Bulk properties analyzed included percent ash, Karl Fisher water content, viscosity and average molecular weight. Chemical properties included monocyclic- and polycyclic-aromatic hydrocarbon (PAH) concentrations, alkylated aromatic concentrations, and concentrations of aliphatic and aromatic fractions. It was found that there was at least an order-of-magnitude variation in all properties measured between the eleven coal tars. Additionally, two coal tars obtained from the same manufactured gas plant site had very different properties, highlighting that there can be wide variations in coal tar properties from different samples obtained from the same site. Similarities were also observed between the coal tars. The relative chemical distributions were similar for all coal tars, and the coal tars predominantly consisted of PAHs, with naphthalene being the single-most prevalent compound. The C{sub 9-22} aromatic fraction, an indicator of all PAHs up to a molecular weight of approximately 276 g mole{sup -1}, showed a strong power-law relationship with the coal tar average molecular weight (MWct). And the concentrations of individual PAHs decreased linearly as MWct increased up to ca. 1000 g mole{sup -1}, above which they remained low and variable. Implications of these properties and their variation with MWct on groundwater quality are discussed. Ultimately, while these similarities do allow generalities to be made about coal tars, the wide range of coal tar bulk and chemical properties reported here highlights the complex nature of coal tars.

Physicochemical Approaches for the Remediation of Former Manufactured Gas Plant Tars

Science.gov (United States)

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.

Cold Preparation of Heroin in a Black Tar Market.

Science.gov (United States)

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.

The purification of coal tar by the addition of quinoline and Zn(oh)/sub 2/

International Nuclear Information System (INIS)

Zhou, P.; Chen, Q.L.; Ao, X.Q.; Kang, C

2017-01-01

The coal tar was purified by the addition of quinoline and Zn(OH)2, in order to decrease the content of carbon and inorganic oxide particles. The effect on the viscosity and ash content of the coal tar were investigated by altering temperature, time, and the amount of quinolone and Zn(OH)2 . When the volume ratio between quinolone and coal tar was 20:1 and the static time was 24 h. The viscosity of three layers decreased with rising temperature. When the static temperature and time was 45 °C and 24 h, respectively. The viscosity of three layers decreased with the arising amount of quinoline. And when the volume ratio between quinolone and coal tar was 20:1 and the temperature was 45 °C. The viscosity of three layers decreased first and then increased with the prolonging of static time. And when the static time of coal tar was 24 h, the viscosity of coal tar is the lowest. Because of the lower viscosity of coal tar, decreasing the content of carbon and ash particles in upper and middle layer, the ash content decreased from 0.168% to 0.092%. The addition of Zn(OH)2 can lead ash content in middle layer decrease to 0.058%. Zn2SiO4 and ZnAl2O4 may be produced due to the reaction between Zn (OH) 2 and SiO2 or Al2O3, which can settle down easily. The results show that the content of carbon and inorganic oxide particles in upper-middle-class (the middle 4/5 of the whole volume) decreased with the addition of quinolone and Zn(OH)2 . When the volume ratio between quinolone and coal tar was 50:2, quality ratio between coal tar and Zn(OH)2 was 20000:1, the mixture were heated up to 45 °C at atmospheric pressure and keeping this constant temperature for 24 h, the ash content in upper-middle-class can decreased to 0.058%. (author)

Opening of the TAR hairpin in the HIV-1 genome causes aberrant RNA dimerization and packaging

Directory of Open Access Journals (Sweden)

Das Atze T

2012-07-01

Full Text Available Abstract Background The TAR hairpin is present at both the 5′ and 3′ end of the HIV-1 RNA genome. The 5′ element binds the viral Tat protein and is essential for Tat-mediated activation of transcription. We recently observed that complete TAR deletion is allowed in the context of an HIV-1 variant that does not depend on this Tat-TAR axis for transcription. Mutations that open the 5′ stem-loop structure did however affect the leader RNA conformation and resulted in a severe replication defect. In this study, we set out to analyze which step of the HIV-1 replication cycle is affected by this conformational change of the leader RNA. Results We demonstrate that opening the 5′ TAR structure through a deletion in either side of the stem region caused aberrant dimerization and reduced packaging of the unspliced viral RNA genome. In contrast, truncation of the TAR hairpin through deletions in both sides of the stem did not affect RNA dimer formation and packaging. Conclusions These results demonstrate that, although the TAR hairpin is not essential for RNA dimerization and packaging, mutations in TAR can significantly affect these processes through misfolding of the relevant RNA signals.

Material Properties and Characteristics for Development of an Expert System for Coal-Tar Sealers

National Research Council Canada - National Science Library

Shoenberger, James

2001-01-01

.... Several coal-tar mixtures that varied with source of the coal-tar emulsion, amount of aggregate, and amount of polymer used in the mixtures were evaluated for their field performance and material properties...

Biomass Gasifier ''Tars'': Their Nature, Formation, and Conversion

Energy Technology Data Exchange (ETDEWEB)

Milne, T. A.; Evans, R. J. (National Renewable Energy Laboratory); Abatzaglou, N. (Kemestrie, Inc.)

1998-11-01

The main purpose of this review is to update the information on gasification tar, the most cumbersome and problematic parameter in any gasification commercialization effort. The work aims to present to the community the scientific and practical aspects of tar formation and conversion (removal) during gasification as a function of the various technological and technical parameters and variables.

Gravel Mobility in a High Sand Content Riverbed

Science.gov (United States)

Haschenburger, J. K.

2017-12-01

In sand-gravel channels, sand may modify gravel transport by changing conditions of entrainment and promoting longer displacements or gravel may inhibit sand transport if concentrated into distinct deposits, which restrict sand supply with consequences for migrating bedform size or form. This study reports on gravel mobility in the lower San Antonio River, Texas, where gravel content in the bed material ranges from about 1% to more than 20%. Sediment transport observations were collected at three U.S. Geological Survey gauging stations by deploying a Helley-Smith sampler with a 0.2 mm mesh bag from which transport rates and mobile grain sizes were determined. The flow rates sampled translate into an annual exceedance expectation from 0.2% to 98%. Gravel transport rates are generally two orders of magnitude smaller than the rates of sand transport. However, the finest gravels are transported at rates on the same order of magnitude as the coarsest sands. At all sites, the 2 and 2.8 mm fractions are transported at the lowest flow rate sampled, suggesting mobility for at least 38% to as much as 98% of the year. Fractions as large as 8 mm are mobilized at flow rates that are expected between 25% and 53% of the year. The largest fractions captured in the sampling (16 to 32 mm) require flows closer to bankfull conditions that occur no more than 0.8% of the year. Results document that some gravel sizes can be frequently transported in low gradient riverbeds with high sand content.

78 FR 29379 - BLM Director's Response to the Appeal by the Governors of Utah and Wyoming of the BLM Assistant...

Science.gov (United States)

2013-05-20

... Shale and Tar Sands Resources on Lands Administered by the Bureau of Land Management (BLM) in Colorado... Shale and Tar Sands Resources on Lands Administered by the BLM in Colorado, Utah, and Wyoming, which..., Lakewood, CO 80215 or Mitchell Leverette, BLM Division Chief, Solid Minerals, 202-912-7113, ( [email protected

Dual vapor extraction on acidic sludge tar at a former refinery

International Nuclear Information System (INIS)

Lear, P.R.; Beall, P.; Townsend, S.

1996-01-01

OHM Remediation Services Corp conducted a pilot-scale demonstration for a novel application of dual vapor extraction technology for the pretreatment of the acid tar sludge material. The acid tar sludge comprised of approximately 60% asphaltene hydrocarbon material, 20% clay, and up to 20% sulfuric acid (H 2 SO 4 ). The liquid layer in the bottom of the pits has a low pH ( 2 ) gas which is released with the sludge material is excavated or handled. The objective of the dual vapor extraction was to remove the SO 2 vapors and liquid layer containing sulfuric acid prior to any further treatment. The dual vapor extraction would reduce the amount of alkaline reagent required for neutralization while eliminating the health and safety concerns. Overall, the DVE pilot demonstration successfully showed that both liquids and vapors could be removed from the acid tar sludge material. The liquid present in the lower portions of the pits will have pH values of 1.0 or less and acidities on the order of 5% H 2 SO 4 . The liquid removed from the acid tar sludge material by a DVE system will have slightly higher pH (∼1.5) and lower alkalinities (∼3% H 2 SO 4 ). The SO 2 concentration in the vapors removed by the DVE system will be variable with initial levels approaching 1,200 ppmv SO 2 . The SO 2 concentration in the vapor phase should decrease with time. A caustic scrubber solution will remove any SO 2 from the vapor phase. After DVE treatment, the acid tar sludge material would have a slightly increased pH and a decreased SO 2 concentration

Toxicity of coal-tar and asphalt sealants to eastern newts, Notophthalmus viridescens

Energy Technology Data Exchange (ETDEWEB)

Bommarito, T.; Sparling, D.W.; Halbrook, R.S. [South Illinois University, Carbondale, IL (United States). Cooperative Wildlife Research Laboratory

2010-09-15

Between 1970 and 2000 the concentration of total polycyclic aromatic hydrocarbons (TPAH) in several lakes across the country increased whereas those of other persistent organic pollutants (POPs) tended to remain stable or declined. Urbanized watersheds experienced greater rises in TPAH concentration compared to non-urban lakes. Sources for urban PAHs include industrial wastes, vehicular exhausts and oil leaks and sealants from pavement surfaces. Both coal-tar and asphalt sealants are used to protect surfaces but runoff from surfaces coated with coal-tar can have mean concentrations of 3500 mg TPAHs kg{sup -1}, much higher than runoff from asphalt-sealed or cement surfaces. Unaltered parent compounds of PAHs can have many lethal and sublethal toxic effects, but oxidation and UV radiation can alter the toxicity of these compounds, sometimes creating degradates that are many times more toxic than parent compounds. The purposes of this study were to determine if coal-tar sealants can be toxic to adult eastern newts (Notophthalmus viridescens) and to compare the toxicity of coal-tar sealant to that of asphalt sealant. Newts were exposed to sediments containing dried sealants ranging from 0 mg kg{sup -1} to 1500 mg kg{sup -1} under simultaneous exposure to UV radiation and visible light to determine concentration/response relationships. No significant mortality occurred with any treatment. Significant effects due to sealants included decreased righting ability and diminished liver enzyme activities. Coal-tar sealant was more effective in inducing these changes than was asphalt sealant.

Tar analysis from biomass gasification by means of online fluorescence spectroscopy

Science.gov (United States)

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.

Tar ball concentrations in the ocean around the Cape of Good Hope before and after a major oil spill

Energy Technology Data Exchange (ETDEWEB)

Eagle, G A; Green, A; Williams, J

1979-11-01

From August 1977 to August 1978, tar ball concentrations around the southwestern coast of South Africa were sampled. Prior to a tanker collision on December 16, 1977, the area was relatively free of floating tar. Following the collision, tar ball concentrations increased; tar was transported by wind and currents, at average speeds of about 1 km/hr. In areas of slack currents, tar was observed for as long as 8 months after the spill. Results provided information about surface current trends.

Determination of oxygen, nitrogen, and silicon in Nigerian fossil fuels by 14 MeV neutron activation analysis

International Nuclear Information System (INIS)

Hannan, M.A.; Oluwole, A.F.; Kehinde, L.O.; Borisade, A.B.

2003-01-01

Classification, assessment, and utilization of coal and crude oil extracts are enhanced by analysis of their oxygen content. Values of oxygen obtained 'by difference' from chemical analysis have proved inaccurate. The oxygen, nitrogen, and silicon content of Nigerian coal samples, crude oils, bitumen extracts, and tar sand samples were measured directly using instrumental fast neutron activation analysis (FNAA). The total oxygen in the coal ranges from 5.20% to 23.3%, in the oil and extracts from 0.14% to 1.08%, and in the tar sands from 38% to 47%. The nitrogen content in the coal ranges from 0.54% to 1.35%, in the crude oil and bitumen extracts from ≤ 0.014% to 0.490%, and in the tar sands from 0.082% to 0.611%. The silicon content in the coal ranges from 1.50% to 8.86%; in the oil and the bitumen extracts it is <1%, and in the tar sands between 25.1% and 37.5%. The results show that Nigerian coals are mostly sub-bituminous. However, one of the samples showed bituminous properties as evidenced by the dry ash-free (daf) percent of carbon obtained. This same sample indicated a higher ash content resulting in a comparatively high percentage of silicon. In oils and tar sands from various locations, a comparison of elements is made. (author)

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

International Nuclear Information System (INIS)

Pittelkow, M.R.; Perry, H.O.; Muller, S.A.; Maughan, W.Z.; O'Brien, P.C.

1981-01-01

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 when 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

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

Science.gov (United States)

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.

Detailed grouping and functional composition of neutral substances in low-temperature tar

Energy Technology Data Exchange (ETDEWEB)

Kalechits, I V; Salimgareeva, F G; Popova, N I; Kurbangaleeva, D K; Klykova, G G

1955-01-01

The grouping and the functional composition of the neutral substances in coal tar were characterized by means of adsorption on silica gel with subsequent chemical analysis of each fraction. The neutral materials were obtained by consecutive treatment of a C/sub 6/H/sub 6/ solution of coal tar with 10 percent alkali and 5 percent H/sub 2/SO/sub 4/ to remove the phenols and the bases. The data show that of the neutral substances (only 75% were identified) 40.5% were aromatic hydrocarbons. Based on a study of all of the data, it was proposed that 90% of the composition of coal tars is aromatic. The physical constants of the separated fractions were determined and are presented in tabular form.

Process for removing heavy metal compounds from heavy crude oil

Science.gov (United States)

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.

Investigation of sulfur-polycyclic aromatic hydrocarbon in coal derived tars of pyrolysis and hydropyrolysis

Energy Technology Data Exchange (ETDEWEB)

Chen, H.; Li, B.; Zhang, B. [Chinese Academy of Sciences, Taiyuan (China). State Key Laboratory of Coal Conversion

1999-07-01

A study was undertaken to characterize sulphur forms in coal derived tars from pyrolysis and hydropyrolysis of bituminous coal and lignite. The pyrolysis tars were analyzed for content of polycyclic aromatic sulfur hydrocarbons (PASH). 5 refs., 3 figs., 3 tabs.

Beta dose due to monazite sands of Kerala

International Nuclear Information System (INIS)

Massand, O.P.; Venkataraman, G.; Dhairyawan, M.P.

1977-01-01

The heavy black mineral sands of the sea coast of Kerala in India contain patches of monazite in concentrations varying between 0.5 to 5%. Monazite contains about 9.5% of thorium oxide (ThO 2 ) and 0.35% of uranium oxide (U 3 O 8 ). The high natural background radiation of this area had been a matter of concern and reports on the measured gamma radiation levels have appeared. The dose contribution due to beta rays emitted by the materials in the sand has been calculated using Loevinger's formula. The annual beta dose is of the order of 4200 mrad and 740 mrad at a height of 5 and 200 cm respectively from ground level. (author)

A look at one of the world`s largest apron feeder drives - Alberta Oil Sands Project

Energy Technology Data Exchange (ETDEWEB)

Persson, O. [Hagglunds Drives Canada Inc., Vancouver, BC (Canada)

1999-10-01

Various types of equipment to transport tar sands to processing plants are discussed, with special attention to the advantages of hydraulic direct drives over conventional electro-mechanical drives. A hydraulic direct drive such as the Hagglund Drive has exceptional starting torque capacity due to the high torque capability of the hydraulic motor. As such, it can be particularly useful in applications where shock loads occur with some frequency, or where many starts and stops are needed. Application of the Hagglund drive to power one of the world`s largest apron feeders in the Alberta Oil Sands is described as an illustration of the exceptional reliability, productivity and performance of this equipment. It has about one five-hundredth of the inertia of an equivalent high speed drive with gear reducer, a feature which is particularly significant in the case of feeders which are known to suffer much downtime due to chain related problems. These types of drives have also been used to great advantage in the process industries like pulp and paper, chemical, rubber and plastics, recycling and steel. 1 tab., 1 fig.

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

Energy Technology Data Exchange (ETDEWEB)

Mise, Takeshi; Matsunami, Hideyuki; Samatey, Fadel A.; Maruyama, Ichiro N., E-mail: ichi@oist.jp [Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami, Okinawa 904-0495 (Japan)

2014-08-27

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 were 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.

Community structure of fish and macrobenthos at selected sites fronting Sand Island, Oahu, Hawaii in relation to the Sand Island Deep Ocean Sewage Outfall, 1990 - 1998 (NODC Accession 0000177)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This report provides the results of nine years of an annual quantitative monitoring of shallow marine communities inshore of the Sand Island Ocean Outfall, Oahu,...

The role of char and tar in determining the gas-phase partitioning of nitrogen during biomass gasification

International Nuclear Information System (INIS)

Broer, Karl M.; Brown, Robert C.

2015-01-01

Highlights: • Switchgrass was gasified at an equivalence ratio of zero and 650–850 °C. • Short residence times were employed to minimize secondary reactions. • Char- and tar-bound nitrogen, NH_3, HCN, and N_2 were all significant products. • Increasing temperature leads to increased release of gaseous nitrogen compounds. • Kinetic models of gasification should include nitrogen release from char and tar. - Abstract: Gasification is an attractive option for converting biomass into fuels and chemicals. Most biomass contains significant amounts of fuel-bound nitrogen (FBN), which partially converts into ammonia (NH_3) and hydrogen cyanide (HCN) during gasification. These nitrogen compounds are problematic as they can lead to NO_X emissions or catalyst poisoning in downstream applications of syngas. FBN can convert to other products as well, including diatomic nitrogen (N_2), char-bound nitrogen (char-N), and tar-bound nitrogen (tar-N). Efforts to predict concentrations of NH_3 and HCN have been hindered by a lack of accurate, comprehensive measurements of nitrogen partitioning among gasification products. The present study gasified switchgrass under allothermal, short residence time conditions and measured NH_3, HCN, char-N, and tar-N as a function of temperature in the range of 650–850 °C with diatomic nitrogen determined by difference. It was found that a major portion of FBN was retained in the char and tar products. As temperature was increased, char and tar were consumed, releasing nitrogen as gaseous NH_3 and HCN. This increase in undesirable nitrogen compounds is contrary to the predictions of most gasification models, which overlook the presence of significant nitrogen in char and tar even if they include tar cracking and char gasification reactions. The results of this study demonstrate that gas-phase reactions alone are not sufficient to predict the fate of nitrogen during gasification. In order for modeling efforts to obtain more accurate

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

Energy Technology Data Exchange (ETDEWEB)

Yang, Y.; Mahler, B.J.; Van Metre, P.C.; Ligouis, B.; Werth, C.J. [University of Illinois Urbana Champaign, Urbana, IL (USA). Dept. of Civil & Environmental Engineering

2010-12-01

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 (Cr{sub 2}O{sub 7}) oxidation and chemo-thermal oxidation at 375{sup o}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 Cr{sub 2}O{sub 7} 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 Cr{sub 2}O{sub 7} 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 Cr{sub 2}O{sub 7} oxidation or CTO-375, and caution is advised when interpreting BC measurements made with these methods.

[Carbon sequestration in soil particle-sized fractions during reversion of desertification at Mu Us Sand land.

Science.gov (United States)

Ma, Jian Ye; Tong, Xiao Gang; Li, Zhan Bin; Fu, Guang Jun; Li, Jiao; Hasier

2016-11-18

The aim of this study was to investigate the effects of carbon sequestration in soil particle-sized fractions during reversion of desertification at Mu Us Sand Land, soil samples were collected from quicksand land, semifixed sand and fixed sand lands that were established by the shrub for 20-55 year-old and the arbor for 20-50 year-old at sand control region of Yulin in Northern Shaanxi Province. The dynamics and sequestration rate of soil organic carbon (SOC) associated with sand, silt and clay were measured by physical fractionation method. The results indicated that, compared with quicksand area, the carbon content in total SOC and all soil particle-sized fractions at bothsand-fixing sand forest lands showed a significant increasing trend, and the maximum carbon content was observed in the top layer of soils. From quicksand to fixed sand land with 55-year-old shrub and 50-year-old arbor, the annual sequestration rate of carbon stock in 0-5 cm soil depth was same in silt by 0.05 Mg·hm -2 ·a -1 . The increase rate of carbon sequestration in sand was 0.05 and 0.08 Mg·hm -2 ·a -1 , and in clay was 0.02 and 0.03 Mg·hm -2 ·a -1 at shrubs and arbors land, respectively. The increase rate of carbon sequestration in 0-20 cm soil layer for all the soil particles was averagely 2.1 times as that of 0-5 cm. At the annual increase rate of carbon, the stock of carbon in sand, silt and clay at the two fixed sand lands were increased by 6.7, 18.1 and 4.4 times after 50-55 year-old reversion of quicksand land to fixed sand. In addition, the average percentages that contributed to accumulation of total SOC by different particles in 0-20 cm soil were in the order of silt carbon (39.7%)≈sand carbon (34.6%) > clay carbon (25.6%). Generally, the soil particle-sized fractions had great carbon sequestration potential during reversion of desertification in Mu Us Sand Land, and the slit and sand were the main fractions for carbon sequestration at both fixed sand lands.

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

Science.gov (United States)

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.

UTILIZATION OF ACTIVATED ZEOLITE AS MOLECULAR SIEVE IN CHROMATOGRAPHIC COLUMN FOR SEPARATION OF COAL TAR COMPOUNDS

Directory of Open Access Journals (Sweden)

Dwi Retno Nurotul Wahidiyah

2010-06-01

Full Text Available Application of activated zeolite (ZAA as molecular sieve to separate compounds of coal tar from vaccum fractional distillation, have been done. The size of zeolite was 10-20 mesh and used as solid phase in column chromatography with length of 30 cm. The first step of the research was coal pyrolisis and the product (tar was distillated by fractional column and vaccum system at reduced pressure 44 cmHg and maximum temperature at 200 oC. The distillate from this procedure was flowed to the column chromatography of zeolite (ZAA. The compound absorbed by zeolite was eluted with varying solvents, i.e: CCl4, acetone and ethanol. Each fraction was then analyzed by gas chromatography. The results showed, zeolite have a capability to separate the compounds of tar and it tends to absorb medium hydrocarbon. The nonpolar eluent [CCl4] gives the better result in eluting tar compound than polar (ethanol or medium polar eluents (acetone.   Keywords: zeolite, coal tar, column chromatography

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

Science.gov (United States)

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.

IDENTIFICATION OF SOME CARCINOGENIC POLYCYCLIC AROMATIC HYDROCARBONS IN BANGLADESHI VEHICLES EXHAUST TAR BY GAS CHROMATOGRAPHY-MASS SPECTROPHOTOMETER

Directory of Open Access Journals (Sweden)

M. Amzad Hossain

2010-06-01

Full Text Available A more sensitive GC-MS method has been established for the determination of some carcinogenic polycyclic aromatic hydrocarbons (PAHs in vehicles exhaust tar samples. The tar samples were extracted using dichloromethane (DMC: n-hexane solvent mixture. A multi-layer clean-up (silica gel/sodium sulphate column was used, followed by glass fiber filter (GFF paper. The method was successfully applied to determine a number of PAHs present in exhaust tar sample of different vehicles of the Atomic Energy Centre, Dhaka, Bangladesh.   Keywords: Carcinogenic polycyclic aromatic hydrocarbons, vehicles tar samples, identification, GC-MS/MS

Coal-tar based pavement sealant toxicity to freshwater macroinvertebrates.

Science.gov (United States)

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 pavement sealants contain bioavailable PAHs that may harm aquatic environments. Copyright 2009 Elsevier Ltd. All rights reserved.

Pelagic tar, dissolved/dispersed petroleum hydrocarbons and plastic distribution in the Cretan Sea, Greece

Energy Technology Data Exchange (ETDEWEB)

Kornilios, S.; Drakopoulos, P.G.; Dounas, C. [Institute of Marine Biology of Crete, Iraklio (Greece). Environmental Dept.

1998-12-01

During the first cruise of R/V `Philia` in July 1997 within the framework of the TALOS programme supported by the Greek Ministry of Physical Planning and Public Works, the sampling of floating tar, litter and sea water for dissolved/dispersed petroleum hydrocarbons (DDPH) was carried out in the Cretan Sea. Analysis of these data has allowed a first assessment of the status of floating marine pollution in the region. DDPH measurements showed a mean concentration of 0.145 {mu}g/l of chrysene equivalents (n = 24). Tar and plastics concentrations were in the range of 1-4280 and 0-1160 {mu}g/m{sup 2}, respectively. Mean pelagic tar concentration was 318 {mu}g/m{sup 2}, more than two times higher than what was reported for the area in previous studies. Based on in situ hydrographic observations there is strong evidence that most of the floating tar enters the Cretan Sea through the Ionian Sea. (author)

Pelagic tar, dissolved/dispersed petroleum hydrocarbons and plastic distribution in the Cretan Sea, Greece

Energy Technology Data Exchange (ETDEWEB)

Kornilios, S.; Drakopoulos, P.G.; Dounas, C. [Institute of Marine Biology of Crete, Iraklio (Greece). Environmental Dept.

1998-12-01

During the first cruise of R/V 'Philia' in July 1997 within the framework of the TALOS programme supported by the Greek Ministry of Physical Planning and Public Works, the sampling of floating tar, litter and sea water for dissolved/dispersed petroleum hydrocarbons (DDPH) was carried out in the Cretan Sea. Analysis of these data has allowed a first assessment of the status of floating marine pollution in the region. DDPH measurements showed a mean concentration of 0.145 {mu}g/l of chrysene equivalents (n = 24). Tar and plastics concentrations were in the range of 1-4280 and 0-1160 {mu}g/m{sup 2}, respectively. Mean pelagic tar concentration was 318 {mu}g/m{sup 2}, more than two times higher than what was reported for the area in previous studies. Based on in situ hydrographic observations there is strong evidence that most of the floating tar enters the Cretan Sea through the Ionian Sea. (author)

Pelagic tar, dissolved/dispersed petroleum hydrocarbons and plastic distribution in the Cretan Sea, Greece

International Nuclear Information System (INIS)

Kornilios, S.; Drakopoulos, P.G.; Dounas, C.

1998-01-01

During the first cruise of R/V 'Philia' in July 1997 within the framework of the TALOS programme supported by the Greek Ministry of Physical Planning and Public Works, the sampling of floating tar, litter and sea water for dissolved/dispersed petroleum hydrocarbons (DDPH) was carried out in the Cretan Sea. Analysis of these data has allowed a first assessment of the status of floating marine pollution in the region. DDPH measurements showed a mean concentration of 0.145 μg/l of chrysene equivalents (n = 24). Tar and plastics concentrations were in the range of 1-4280 and 0-1160 μg/m 2 , respectively. Mean pelagic tar concentration was 318 μg/m 2 , more than two times higher than what was reported for the area in previous studies. Based on in situ hydrographic observations there is strong evidence that most of the floating tar enters the Cretan Sea through the Ionian Sea. (author)

A look at one of the world's largest apron feeder drives - Alberta Oil Sands Project

Energy Technology Data Exchange (ETDEWEB)

Persson, O. (Hagglunds Drives Canada Inc., Vancouver, BC (Canada))

1999-01-01

Various types of equipment to transport tar sands to processing plants are discussed, with special attention to the advantages of hydraulic direct drives over conventional electro-mechanical drives. A hydraulic direct drive such as the Hagglund Drive has exceptional starting torque capacity due to the high torque capability of the hydraulic motor. As such, it can be particularly useful in applications where shock loads occur with some frequency, or where many starts and stops are needed. Application of the Hagglund drive to power one of the world's largest apron feeders in the Alberta Oil Sands is described as an illustration of the exceptional reliability, productivity and performance of this equipment. It has about one five-hundredth of the inertia of an equivalent high speed drive with gear reducer, a feature which is particularly significant in the case of feeders which are known to suffer much downtime due to chain related problems. These types of drives have also been used to great advantage in the process industries like pulp and paper, chemical, rubber and plastics, recycling and steel. 1 tab., 1 fig.

77 FR 48431 - Safety Zone for Fireworks Display, Pamlico and Tar Rivers; Washington, NC

Science.gov (United States)

2012-08-14

... near the Pamlico and Tar Rivers to commemorate Beaufort County's 300th anniversary. The temporary... 1625-AA00 Safety Zone for Fireworks Display, Pamlico and Tar Rivers; Washington, NC AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone on...

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

Energy Technology Data Exchange (ETDEWEB)

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

1979-05-01

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. 4 figures, 6 tables.

Some studies on tar pillets at Veraval coast (Gujarat)

Digital Repository Service at National Institute of Oceanography (India)

Kadam, A.N.

Infrared spectroscopic (IR) analysis indicated that the tar pillets contain saturated hydrocarbons particularly higher homologues of n-paraffins, unsaturated and carbonyl type of polar compounds. Gas chromatographic (GLC) fingerprint pattern...

Syncrude Canada Ltd. 1998 annual report

International Nuclear Information System (INIS)

1999-01-01

Syncrude Canada Ltd. operates the Syncrude Project which is a joint venture of 10 partners responsible for operating the largest crude oil-producing oil sands facility in the world. The facility provides more than 13 per cent of Canada's annual oil requirements. Syncrude's product is Syncrude Sweet Blend (SSB) which is a high quality, light, sweet crude oil. SSB is produced through an integrated process that begins with the surface mining of the oil sands. Annual SSB shipments for 1998 were 76.7 million barrels, the 17th annual record in 20 years of operation. In 1998, construction also began on the second ore train of the North Mine and its associated hydrotransport facilities. The report presents an overview of financial highlights and operating results for 1998, paying appropriate tribute to innovation that has been responsible for the continuous improvements made by the Consortium. The report also expresses the Joint Venture Partners' long-term commitment to applying the latest technology, improving workforce productivity, environmental performance, an even higher quality product, and more cost-effective ways to do business. 2 tabs

Hydrogen production from biomass tar by catalytic steam reforming

International Nuclear Information System (INIS)

Yoon, Sang Jun; Choi, Young-Chan; Lee, Jae-Goo

2010-01-01

The catalytic steam reforming of model biomass tar, toluene being a major component, was performed at various conditions of temperature, steam injection rate, catalyst size, and space time. Two kinds of nickel-based commercial catalyst, the Katalco 46-3Q and the Katalco 46-6Q, were evaluated and compared with dolomite catalyst. Production of hydrogen generally increased with reaction temperature, steam injection rate and space time and decreased with catalyst size. In particular, zirconia-promoted nickel-based catalyst, Katalco 46-6Q, showed a higher tar conversion efficiency and shows 100% conversion even relatively lower temperature conditions of 600 deg. C. Apparent activation energy was estimated to 94 and 57 kJ/mol for dolomite and nickel-based catalyst respectively.

Environmental Impacts of Sand Exploitation. Analysis of Sand Market

Directory of Open Access Journals (Sweden)

Marius Dan Gavriletea

2017-06-01

Full Text Available Sand is an indispensable natural resource for any society. Despite society’s increasing dependence on sand, there are major challenges that this industry needs to deal with: limited sand resources, illegal mining, and environmental impact of sand mining. The purpose of this paper is twofold: to present an overview of the sand market, highlighting the main trends and actors for production, export and import, and to review the main environmental impacts associated with sand exploitation process. Based on these findings, we recommend different measures to be followed to reduce negative impacts. Sand mining should be done in a way that limits environmental damage during exploitation and restores the land after mining operations are completed.

Luminescence monitoring of oil or tar contamination for industrial hygiene

International Nuclear Information System (INIS)

Gammage, R.B.; Vo-Dinh, T.

1980-01-01

Synfuel plants produce potentially carcinogenic oils and tars. Exposure of workers to these tars and oils is difficult to avoid completely and occurs via direct contact with dirty surfaces or condensation of escaped fumes onto or within the body. Surface skin, measurements are made directly with a near-ultraviolet luminoscope employing a fiber optics lightguide and a stethoscopic cap pressed against the skin. This instrument is especially suitable for measuring ng to μg/cm 2 amounts of residual contamination remaining on the surface of the skin after washing. To minimize the potential for carcinogenicity, the excitating ultraviolet light intensity is only 1/100th that of sunlight. (orig.)

Effects of electric current upon catalytic steam reforming of biomass gasification tar model compounds to syngas

International Nuclear Information System (INIS)

Tao, Jun; Lu, Qiang; Dong, Changqing; Du, Xiaoze; Dahlquist, Erik

2015-01-01

Highlights: • ECR technique was proposed to convert biomass gasification tar model compounds. • Electric current enhanced the reforming efficiency remarkably. • The highest toluene conversion reached 99.9%. • Ni–CeO 2 /γ-Al 2 O 3 exhibited good stability during the ECR performance. - Abstract: Electrochemical catalytic reforming (ECR) technique, known as electric current enhanced catalytic reforming technique, was proposed to convert the biomass gasification tar into syngas. In this study, Ni–CeO 2 /γ-Al 2 O 3 catalyst was prepared, and toluene was employed as the major feedstock for ECR experiments using a fixed-bed lab-scale setup where thermal electrons could be generated and provided to the catalyst. Several factors, including the electric current intensity, reaction temperature and steam/carbon (S/C) ratio, were investigated to reveal their effects on the conversion of toluene as well as the composition of the gas products. Moreover, toluene, two other tar model compounds (benzene and 1-methylnaphthalene) and real tar (tar-containing wastewater) were subjected to the long period catalytic stability tests. All the used catalysts were analyzed to determine their carbon contents. The results indicated that the presence of electric current enhanced the catalytic performance remarkably. The toluene conversion reached 99.9% under the electric current of 4 A, catalytic temperature of 800 °C and S/C ratio of 3. Stable conversion performances of benzene, 1-methylnaphthalene and tar-containing wastewater were also observed in the ECR process. H 2 and CO were the major gas products, while CO 2 and CH 4 were the minor ones. Due to the promising capability, the ECR technique deserves further investigation and application for efficient tar conversion

Pyrolysis kinetics of phenols from lignite semicoking tar

Energy Technology Data Exchange (ETDEWEB)

Platonov, V.V.; Polovetskaya, O.S.; Proskuryakov, V.A.; Shavyrina, O.A. [Leo Tolstoy Tula State Pedag University, Tula (Russian Federation)

2002-11-01

The features of pyrolysis of phenols from lignite semicoking tar were studied. The activation energy and order of the reactions of accumulation of methane, hydrogen, carbon monoxide and dioxide, naphthalene and its methyl homologs, phenols, and isomeric cresols and dimethylphenols were determined.

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

Energy Technology Data Exchange (ETDEWEB)

Haydary, J., E-mail: juma.haydary@stuba.sk [Institute of Chemical and Environmental Engineering, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, 812 37 Bratislava (Slovakia); Susa, D.; Dudáš, J. [Institute of Chemical and Environmental Engineering, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, 812 37 Bratislava (Slovakia)

2013-05-15

Highlights: ► Pyrolysis of aseptic packages was carried out in a laboratory flow reactor. ► Distribution of tetrapak into the product yields was obtained. ► Composition of the pyrolysis products was estimated. ► Secondary thermal and catalytic decomposition of tars was studied. ► Two types of catalysts (dolomite and red clay marked AFRC) were used. - Abstract: 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 H{sub 2}, CO, CH{sub 4}, CO{sub 2} 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.

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

Science.gov (United States)

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.

Fungal cultures of tar bush and creosote bush for production of two phenolic antioxidants (pyrocatechol and gallic acid).

Science.gov (United States)

Ventura, J; Gutiérrez-Sanchez, G; Rodríguez-Herrera, R; Aguilar, C N

2009-01-01

'Tar bush' and 'creosote bush' were substrates of fungal cultivation for tannase production and gallic acid and pyrocatechol accumulation. Aspergillus niger GH1 grew similarly on both plant materials under solid state culture conditions, reaching maximal levels after 4 d. Fungal strain degraded all tannin content of creosote bush after 4 d of fermentation and >75 % of tar bush after 5 d. Higher level of tannase activity was detected in tar bush fermentation. Biotransformation of tannins to gallic acid was high (93 % in creosote bush and 89 % in tar bush). Pyrocatechol was released poorly. Kinetic parameters of tannin conversion were calculated.

Family physicians and youth tobacco-free education: outcomes of the Colorado Tar Wars program.

Science.gov (United States)

Cain, Jeffrey J; Dickinson, W Perry; Fernald, Douglas; Bublitz, Caroline; Dickinson, L Miriam; West, David

2006-01-01

Tar Wars is a national school-based tobacco-free education program operated by the American Academy of Family Physicians. The Tar Wars lesson uses an interactive 45-min session taught by volunteer family physicians in 4th- and 5th-grade classrooms and focuses on the short-term image-based consequences of tobacco use. In this study, we evaluated the effectiveness of the Tar Wars program in Colorado with both quantitative and qualitative measures. Students participating in the quantitative evaluation were tested before and after a Tar Wars teaching session using a 14-question test covering the short-term and image-based consequences of tobacco use, cost of smoking, tobacco advertising, and social norms of tobacco use. Qualitative evaluation of the program included guided telephone interviews and focus groups with participating students, teachers, and presenters. Quantitative evaluation showed statistically significant improvement in correct responses for the 14 questions measured with an average increase in correct responses from 8.95 to 10.23. Three areas recommended by the Centers for Disease Control (CDC) for youth tobacco prevention showed greater change in correct responses, including cost of smoking, truth of tobacco advertising, and peer norms of tobacco use. Qualitative evaluation found that the overall message of the session was well received, that previously known tobacco information was reinforced by its presentation in a novel format, and that new information learned included cost of smoking, truth of tobacco advertising, and peer norms of tobacco use. The Tar Wars lesson plan is effective in increasing students' understanding about the short-term consequences of tobacco use, cost of tobacco use, truth of tobacco advertising, and peer norms. Tar Wars meets the CDC guidelines as one component of effective comprehensive youth tobacco prevention.

No Increased Risk of Cancer after Coal Tar Treatment in Patients with Psoriasis or Eczema

NARCIS (Netherlands)

Roelofzen, Judith H. J.; Aben, Katja K. H.; Oldenhof, Ursula T. H.; Coenraads, Pieter-Jan; Alkemade, Hans A.; van de Kerkhof, Peter C. M.; van der Valk, Pieter G. M.; Kiemeney, Lambertus A. L. M.

Coal tar is an effective treatment for psoriasis and eczema, but it contains several carcinogenic compounds. Occupational and animal studies have shown an increased risk of cancer after exposure to coal tar. Many dermatologists have abandoned this treatment for safety reasons, although the risk of

Tar removal from biomass derived fuel gas by pulsed corona discharges: chemical kinetic study II

NARCIS (Netherlands)

Nair, S.A.; Yan, K.; Pemen, A.J.M.; Heesch, van E.J.M.; Ptasinski, K.J.; Drinkenburg, A.A.H.

2005-01-01

Tar (heavy hydrocarbon or poly aromatic hydrocarbon (PAH)) removal from biomass derived fuel gas is one of the biggest obstacles in its utilization for power generation. We have investigated pulsed corona as a method for tar removal. Our previous experimental results indicate the energy consumption

Abating coal tar seepage into surface water bodies using sheet piles with sealed interlocks

International Nuclear Information System (INIS)

Collingwood, B.I.; Boscardin, M.D.; Murdock, R.F.

1995-01-01

A former coal tar processing facility processed crude coal tar supplied from manufactured gas plants in the area. Coal-tar-contaminated ground water from the site was observed seeping through an existing timber bulkhead along a tidal river and producing a multicolored sheen on the surface of the river. As part of a short-term measure to abate the seepage into the river, 64-m long anchored sheet pile wall with sheet pile wing walls at each end was constructed inland of the of the timber bulkhead. The sheet piles extended to low-permeability soils at depth and the interlocks of the sheet piles were provided with polyurethane rubber seals. Based on postconstruction observations for leakage and sheens related to leakage, the steel sheet piles with polyurethane rubber interlock seals appeared to provide a successful seal and abate coal-tar-contaminated ground water seepage into the river. The tie rod penetration sealing proved to be a more problematic detail, but through several postconstruction grouting episodes, an effective seal was produced

Effect of the rate of heating on the quality of the primary tar in low-temperature coal-carbonization process

Energy Technology Data Exchange (ETDEWEB)

Turskii, Y I

1956-01-01

Two stages are observed. The first stage yields products of the primary and partial decomposition of coal, mainly water, CO/sub 2/, and CO as decomposition products of functional groups (-COOH, > CO, - OH, and so forth). No tar is formed in this stage. The structural decomposition and tar formation occur in the second stage. The rate of heating is important for the quality of the tar obtained. The slow rate of heating with both stages following each other yields a good-quality tar, richer in C and H, with lower O content. In case of high rate of heating both stages overlap. The tar is of poorer quality with higher specific gravity, and contains more O and asphaltenes. The complete experimental data are given in detail.

BTX production by in-situ contact reforming of low-temperature tar from coal with zeolite-derived catalysts; Zeolite kei shokubai wo mochiita sekitan teion tar no sesshoku kaishitsu ni yoru BTX no seisei

Energy Technology Data Exchange (ETDEWEB)

Matsunaga, T.; Fuda, K.; Murakami, K.; Kyo, M.; Hosoya, S.; Kobayashi, S. [Akita University, Akita (Japan). Mining College

1996-10-28

On BTX production process from low-temperature tar obtained by pyrolysis of coal, the effect of exchanged metallic species and reaction temperature were studied using metallic ion-exchanged Y-zeolite as catalyst. In experiment, three kinds of coals with different produced tar structures such as Taiheiyo and PSOC-830 sub-bituminous coals and Loy Yang brown coal were used. Y-zeolite ion-exchanged with metal chloride aqueous solution was used as catalyst. Zn{sup 2+}, Ni{sup 2+} and In{sup 3+} were used as metal ions to be exchanged. The experiment was conducted by heating a pyrolysis section up to 600{degree}C for one hour after preheating a contact reforming section up to a certain proper temperature. As a result, the Ni system catalyst was effective for BTX production from aromatic-abundant tar, while the Zn system one from lower aromatic tar. In general, relatively high yields of toluene and xylene were obtained at lower temperature, while those of benzene at higher temperature. 4 figs., 1 tab.

Evidence for conformational flexibility in the Tat-TAR recognition motif of cyclin T1

International Nuclear Information System (INIS)

Das, Chandreyee; Edgcomb, Stephen P.; Peteranderl, Ralph; Chen, Lily; Frankel, Alan D.

2004-01-01

Cyclin T1 (CycT1) is a cellular transcription elongation factor that also participates in Tat-mediated activation of several lentiviral promoters. In human immunodeficiency virus (HIV), CycT1 is required for Tat to bind tightly to TAR and interacts in the ternary complex via its Tat-TAR recognition motif (TRM). In the related bovine immunodeficiency virus (BIV), Tat recognizes its cognate TAR element with high affinity and specificity in the absence of CycT1. At both promoters, CycT1 recruits the Cdk9 kinase, which phosphorylates RNA polymerase II to generate processive transcription complexes. To examine the physical properties of CycT1, we purified a functional domain corresponding to residues 1-272 and found that it possesses a stably folded core, as judged by partial proteolysis and circular dichroism experiments. Interestingly, the C-terminal 20 residues corresponding to the TRM appear conformationally flexible or disordered. The TRM of the bovine CycT1 (bCycT1) is similarly sensitive to proteolysis yet differs in sequence from the human protein. In particular, bCycT1 lacks a cysteine at residue 261 known to be critical for HIV but not BIV ternary complex formation, and mutagenesis data are consistent with a proposed role for this cysteine in metal binding. The apparent flexibility of the TRM suggests that conformational rearrangements may accompany formation of CycT1-Tat-TAR ternary complexes and may contribute to different TAR recognition strategies in different lentiviruses

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

Energy Technology Data Exchange (ETDEWEB)

Miller, R.S.; Bellan, J. [California Inst. of Tech., Pasadena, CA (United States). Jet Propulsion Lab.

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 from 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.

Analysis of the use of coal tar as a binder in bituminous mixtures, using Marshall and Ramcodes methodologies

International Nuclear Information System (INIS)

Ochoa-Díaz, R

2013-01-01

This paper presents an alternative use of coal tar, a by-product of the steel industry, given the problems of accumulation and negative environmental impact. Therefore, it is necessary to analyze the incorporation of coal tar as a binder in paving mixtures. First, this paper presents the origin, description of the main characteristics, and properties of tar. Then, this paper evaluates the mix of coal tar by means of the RAMCODES and Marshall methodologies to determine its resistance. The results of the tests explain the physical and mechanical properties of the mix. Taking into account the results of both methods, this paper makes a comparison to determine the suitability of the RAMCODES methodology in the mix design. Finally, it analyzes the alternatives to coal tar that can be used as binders in bituminous mixes for pavement and the advantages of their uses under some specific conditions

Quantitative analysis of phenol and alkylphenols in Brazilian coal tar

Directory of Open Access Journals (Sweden)

Elina Bastos Caramão

2004-04-01

Full Text Available The main purpose of this work is the identification and quantification of phenolic compounds in coal tar samples from a ceramics factory in Cocal (SC, Brazil. The samples were subjected to preparative scale liquid chromatography, using Amberlyst A-27TM ion-exchange resin as stationary phase. The fractions obtained were classified as "acids" and "BN" (bases and neutrals. The identification and quantification of phenols, in the acid fraction, was made by gas chromatography coupled to mass spectrometry (GC/MS. Nearly twenty-five phenols were identified in the samples and nine of them were also quantified. The results showed that coal tar has large quantities of phenolic compounds of industrial interest.

Shoreline erosion and decadal sediment accumulation in the Tar-Pamlico estuary, North Carolina, USA: A source-to-sink analysis

Science.gov (United States)

Eulie, Devon O.; Corbett, D. Reide; Walsh, J. P.

2018-03-01

Estuaries contain vital habitats and it is important to understand how these areas respond to human activities and natural processes such as sea-level rise and wave attack. As estuarine shorelines erode or become modified with hard structures, there is potential for significantly altering the availability of sediment and the filling of coastal systems. This study used a source-to-sink approach and quantified rates of shoreline erosion in the Tar-Pamlico sub-estuary, a tributary of the larger Albemarle-Pamlico Estuarine System (APES). The average shoreline change rate (SCR) determined using an end-point method was -0.5 ± 0.9 m yr-1 for the Tar-Pamlico. Incorporating bulk density estimates, this contributes 0.6 × 105 tons of fine sediment to the system annually, or after accounting for fluvial input, about 40% of the total sediment supply to the sub-estuary. The role of the Tar-Pamlico as a sink for these sediments was addressed using the radionuclide tracers 210Pb and 137Cs. Radionuclide activities and sediment accumulation rates identified several depositional regions, in particular in the middle of the estuary. Linear sediment accumulation rates ranged from 0.10 ± 0.02 to 0.38 ± 0.02 g cm-2 yr-1, and total storage of fine sediment in the system was 1.6 × 105 t yr-1. It was not possible to confidently discern a change in the rate of shoreline erosion or seabed accumulation. A preliminary budget for fine sediments (grain-size <63 μm) was then calculated to compare erosional sources with sedimentary sinks. Almost all (∼93.0%) of the fine sediment entering the system was accumulated and stored, while only about 7.0% was exported to Pamlico Sound.

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

Science.gov (United States)

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.

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

Science.gov (United States)

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.

Source identification of a tar residue from Mumbai Beach

Digital Repository Service at National Institute of Oceanography (India)

Kadam, A; Rokade, M.A

A tar residue from Mumbai Beach, Maharashtra, India was matched with the suspected source sample from a tanker using UV, IR and GLC techniques. Negligible differences in several ratios of UV absorbances and ratios of infrared transmittances...

Anomalous capillary flow of coal tar pitches

Energy Technology Data Exchange (ETDEWEB)

Saint Romain, J.L.; Lahaye, J.; Ehrburger, P.; Couderc, P.

1986-06-01

Capillary flow of liquid coal tar pitch into a coke bed was studied. Anomalies in the flow could not be attributed to a plugging effect for mesophase content lower than 20 wt%. The flow behaviour of small pitch droplets can be correlated with the change in physicochemical properties, as measured by the glass transition temperature, on penetration into the coke bed. 4 references.

Sand transportation and reverse patterns over leeward face of sand dune

Science.gov (United States)

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

HuMiTar: A sequence-based method for prediction of human microRNA targets

Directory of Open Access Journals (Sweden)

Chen Ke

2008-12-01

Full Text Available Abstract Background MicroRNAs (miRs are small noncoding RNAs that bind to complementary/partially complementary sites in the 3' untranslated regions of target genes to regulate protein production of the target transcript and to induce mRNA degradation or mRNA cleavage. The ability to perform accurate, high-throughput identification of physiologically active miR targets would enable functional characterization of individual miRs. Current target prediction methods include traditional approaches that are based on specific base-pairing rules in the miR's seed region and implementation of cross-species conservation of the target site, and machine learning (ML methods that explore patterns that contrast true and false miR-mRNA duplexes. However, in the case of the traditional methods research shows that some seed region matches that are conserved are false positives and that some of the experimentally validated target sites are not conserved. Results We present HuMiTar, a computational method for identifying common targets of miRs, which is based on a scoring function that considers base-pairing for both seed and non-seed positions for human miR-mRNA duplexes. Our design shows that certain non-seed miR nucleotides, such as 14, 18, 13, 11, and 17, are characterized by a strong bias towards formation of Watson-Crick pairing. We contrasted HuMiTar with several representative competing methods on two sets of human miR targets and a set of ten glioblastoma oncogenes. Comparison with the two best performing traditional methods, PicTar and TargetScanS, and a representative ML method that considers the non-seed positions, NBmiRTar, shows that HuMiTar predictions include majority of the predictions of the other three methods. At the same time, the proposed method is also capable of finding more true positive targets as a trade-off for an increased number of predictions. Genome-wide predictions show that the proposed method is characterized by 1.99 signal

Environmental isotopes in North African groundwaters; and the Dahna sand-dune study, Saudi Arabia

International Nuclear Information System (INIS)

Sonntag, C.; Thoma, G.; Muennich, K.O.; Dincer, T.; Klitzsch, E.

1980-01-01

I. North Saharian palaeowaters were mainly formed during a long humid period between 50,000 and 20,000 years BP., which was followed by a cool dry period from 20,000 to 14,000 years BP. These palaeowaters show a significant west-east decrease in deuterium and 18 O because of past groundwater formation by local rainfall from the western drift. Sahel zone groundwaters seem to show meridional variation of deuterium and 18 O due to a tropical convective influence. II. A computer model estimate of the alternate play between rainwater infiltration and evaporation in the Dahna sand-dune (near Riyadh, Saudi Arabia) yields a mean annual groundwater recharge of 20 mm annually which agrees with that obtained from bomb tritium vertical profiles of the sand moisture. The model also describes the deuterium and 18 O profiles. (author)

Assessment of Suspended Sand Availability under Different Flow Conditions of the Lowermost Mississippi River at Tarbert Landing during 1973–2013

Directory of Open Access Journals (Sweden)

Sanjeev Joshi

2015-12-01

Full Text Available Rapid land loss in the Mississippi River Delta Plain has led to intensive efforts by state and federal agencies for finding solutions in coastal land restoration in the past decade. One of the proposed solutions includes diversion of the Mississippi River water into drowning wetland areas. Although a few recent studies have investigated flow-sediment relationships in the Lowermost Mississippi River (LmMR, defined as the 500 km reach from the Old River Control Structure to the river’s Gulf outlet, it is unclear how individual sediment fractions behave under varying flow conditions of the river. The information can be especially pertinent because the quantity of coarse sands plays a critical role for the Mississippi-Atchafalaya River deltaic development. In this study, we utilized long-term (1973–2013 records on discharge and sediments at Tarbert Landing of the LmMR to assess sand behavior and availability under different river flow regimes, and extreme sand transport events and their recurrence. We found an average annual sand load (SL of 27.2 megatonnes (MT during 1973 and 2013, varying largely from 3.37 to 52.30 MT. For the entire 41-year study period, a total of approximately 1115 MT sand were discharged at Tarbert Landing, half of which occurred during the peak 20% flow events. A combination of intermediate, high and peak flow stages (i.e., river discharge was ≥18,000 cubic meter per second produced about 71% of the total annual SL within approximately 120 days of a year. Based on the long-term sediment assessment, we predict that the LmMR has a high likelihood to transport 4 to 446 thousand tonnes of sand every day over the next 40 years, during which annual sand loads could reach a maximum of 51.68 MT. Currently, no effective plan is in place to utilize this considerably high sand quantity and we suggest that river engineering and sediment management in the LmMR consider practices of hydrograph-based approach for maximally capturing

Recovery of naphthalene, anthracene, etc. , from tar

Energy Technology Data Exchange (ETDEWEB)

1920-12-25

A process is described for the recovery of naphthalene, anthracene, and the like from tar oils and similar liquors, characterized in that the oil is treated in a rapidly rotating hammer mill, such as a colloid mill, with water sufficient, in the presence or absence of suitable solvents, for the only portion preferably in the presence of emulsifiers; and is filtered through a filter with fine pores.

Lab-scale pyrolysis of the Automotive Shredder Residue light fraction and characterization of tar and solid products.

Science.gov (United States)

Anzano, Manuela; Collina, Elena; Piccinelli, Elsa; Lasagni, Marina

2017-06-01

The general aim of this study is the recovery of Automotive Shredder Residue (ASR). The ASR light fraction, or car fluff, that was collected at an Italian shredding plant was pyrolysed at various temperatures (500-800°C) in a lab-scale reactor. The condensable gases (tar) and solid residue yields increased with decreasing temperature, and these products were characterized to suggest a potential use to reclaim them. The higher heating value (HHV) of tar was 34-37MJ/kg, which is comparable with those of fossil fuels. Furthermore, the ash content was low (0.06-4.98%). Thus, tar can be used as an alternative fuel. With this prospect, the concentrations of polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in tar were determined. The toxicity of tar changes with temperature (1-5ng I-TEQ/g), and the PCDFs significantly contribute to tar toxicity, which was 75-100% with a maximum of 99.6% at 700°C. Regarding the characterization of the solid residue, the low HHV (2.4-3.3MJ/kg) does not make it suitable for energy recovery. Regarding material recovery, we considered its use as a filler in construction materials or a secondary source for metals. It shows a high metal concentration (280,000-395,000mg/kg), which is similar at different pyrolysis temperatures. At 500°C, polycyclic aromatic hydrocarbons (PAHs) were not detected in the solid residue, whereas the maximum total PAH concentration (19.41ng/g, 700°C) was lower than that in fly ash from MSWI. In conclusion, 500°C is a suitable pyrolysis temperature to obtain valuable tar and solid residue. Copyright © 2017 Elsevier Ltd. All rights reserved.

Concentrations of polycyclic aromatic hydrocarbons (PAHs) and azaarenes in runoff from coal-tar- and asphalt-sealcoated pavement

International Nuclear Information System (INIS)

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. - Highlights: • We compare PAH and azaarene concentrations in runoff from coal-tar- and asphalt-sealed pavement. • Concentrations in coal-tar-sealcoat runoff greatly exceeded those in asphalt-sealcoat runoff. • Decreases in azaarenes and LMW PAHs were offset by increases in HMW PAHs. • PAH concentrations in coal-tar-sealcoat runoff remained high for months after application. - Concentrations of PAHs in runoff from pavement with coal-tar-based sealcoat continue to be elevated for at least 3 months following sealcoat application

Papers of the Canadian Institute's 3. annual conference : oil sands supply and infrastructure : labour supply, upgraders, transportation, pipelines

International Nuclear Information System (INIS)

2005-01-01

The focus of this conference was on the development of the oil sands industry, with specific reference to issues concerning supply and infrastructure. Energy source development and transmission issues were discussed, as well as transportation systems. The impact of increased oil sands development on pipelines was also examined. Various fuel options were discussed, including the use of hydrogen, natural gas and alternate fuels in manufacturing and processing plants. Economic drivers and the creation of new markets were examined, and various export opportunities were reviewed. The environmental impact of increased oil sands activity was discussed, with specific reference to the Boreal regions. Management challenges in the oil sands industry were also discussed along with issues concerning human resources, labour supply, training and education. The conference featured 15 presentations, of which 13 have been catalogued separately for inclusion in this database. refs., tabs., figs

The influence of groundwater depth on coastal dune development at sand flats close to inlets

Science.gov (United States)

Silva, Filipe Galiforni; Wijnberg, Kathelijne M.; de Groot, Alma V.; Hulscher, Suzanne J. M. H.

2018-05-01

A cellular automata model is used to analyze the effects of groundwater levels and sediment supply on aeolian dune development occurring on sand flats close to inlets. The model considers, in a schematized and probabilistic way, aeolian transport processes, groundwater influence, vegetation development, and combined effects of waves and tides that can both erode and accrete the sand flat. Next to three idealized cases, a sand flat adjoining the barrier island of Texel, the Netherlands, was chosen as a case study. Elevation data from 18 annual LIDAR surveys was used to characterize sand flat and dune development. Additionally, a field survey was carried out to map the spatial variation in capillary fringe depth across the sand flat. Results show that for high groundwater situations, sediment supply became limited inducing formation of Coppice-like dunes, even though aeolian losses were regularly replenished by marine import during sand flat flooding. Long dune rows developed for high sediment supply scenarios which occurred for deep groundwater levels. Furthermore, a threshold depth appears to exist at which the groundwater level starts to affect dune development on the inlet sand flat. The threshold can vary spatially depending on external conditions such as topography. On sand flats close to inlets, groundwater is capable of introducing spatial variability in dune growth, which is consistent with dune development patterns found on the Texel sand flat.

Site-selective probing of cTAR destabilization highlights the necessary plasticity of the HIV-1 nucleocapsid protein to chaperone the first strand transfer

Science.gov (United States)

Godet, Julien; Kenfack, Cyril; Przybilla, Frédéric; Richert, Ludovic; Duportail, Guy; Mély, Yves

2013-01-01

The HIV-1 nucleocapsid protein (NCp7) is a nucleic acid chaperone required during reverse transcription. During the first strand transfer, NCp7 is thought to destabilize cTAR, the (−)DNA copy of the TAR RNA hairpin, and subsequently direct the TAR/cTAR annealing through the zipping of their destabilized stem ends. To further characterize the destabilizing activity of NCp7, we locally probe the structure and dynamics of cTAR by steady-state and time resolved fluorescence spectroscopy. NC(11–55), a truncated NCp7 version corresponding to its zinc-finger domain, was found to bind all over the sequence and to preferentially destabilize the penultimate double-stranded segment in the lower part of the cTAR stem. This destabilization is achieved through zinc-finger–dependent binding of NC to the G10 and G50 residues. Sequence comparison further revealed that C•A mismatches close to the two G residues were critical for fine tuning the stability of the lower part of the cTAR stem and conferring to G10 and G50 the appropriate mobility and accessibility for specific recognition by NC. Our data also highlight the necessary plasticity of NCp7 to adapt to the sequence and structure variability of cTAR to chaperone its annealing with TAR through a specific pathway. PMID:23511968

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

Science.gov (United States)

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.

Reclaimability of the spent sand mixture – sand with bentonite – sand with furfuryl resin

Directory of Open Access Journals (Sweden)

J. Dańko

2011-04-01

Full Text Available Introduction of new binding materials and new technologies of their hardening in casting moulds and cores production requires theapplication of reclamation methods adequate to their properties as well as special devices realizing tasks. The spent sands circulationsystem containing the same kind of moulding and core sands is optimal from the point of view of the expected reclamation results.However, in the face of a significant variability of applied technologies and related to them various reclamation methods, the need - of theobtained reclamation products assessment on the grounds of systematic criteria and uniform bases – arises, with a tendency of indicatingwhich criteria are the most important for the given sand system. The reclaimability results of the mixture of the spent moulding sand withGeko S bentonite and the spent core sand with the Kaltharz 404U resin hardened by acidic hardener 100 T3, are presented in the paper.Investigations were performed with regard to the estimation of an influence of core sands additions (10 –25% on the reclaimed materialquality. Dusts and clay content in the reclaim, its chemical reaction (pH and ignition loss were estimated. The verification of the reclaiminstrumental assessment was performed on the basis of the technological properties estimation of moulding sand with bentonite, where the reclaimed material was used as a matrix.

Quantitative determination of acid oils in low-temperature coal tar by means of fractional distillation

Energy Technology Data Exchange (ETDEWEB)

Jaeger, A

1950-01-01

The aromatic hydroxy compounds in low-temperature tar were separated, and 75 compounds in the boiling range 180/sup 0/ to 320/sup 0/ isolated by means of fractional distillation in packed columns of at least 45 theoretical plates. Mixtures not separable by fractionation were separated by means of other physicochemical or chemical methods. Hydroxy compounds with boiling point up to 230/sup 0/C were detemined quantitatively, as were the phenols present in low-temperature carbonization liquors. With the Krupp-Lurgi process of low-temperature carbonization, 1.8% phenol, 1.8% o-cresol, and 3.6% m-p-cresols were formed. The tar contained up to 1.3% 1:3:5-xylenol and up to 0.9% 1:2:4-xylenol. Of the 12.1% v/v of phenol, cresols, and xylenols present in tar, 11.2% were determined quantitatively, and 9 hydroxy compounds were identified in the remaining 0.9%. On the basis of these investigations, a technical plant that permitted the recovery of pure low-temperature tar phenols and the preparation of a number of different phenol resins from the mixtures was erected.

Studies estimating the dermal bioavailability of polynuclear aromatic hydrocarbons from manufactured plant tar-contaminated soils

International Nuclear Information System (INIS)

Roy, T.A.; Krueger, A.J.; Taylor, B.B.; Mauro, D.M.; Goldstein, L.S.

1998-01-01

In vitro percutaneous absorption studies were performed with contaminated soils or organic extracts of contaminated soils collected at manufactured gas plant (MGP) sites. The MGP tar contaminated soils were found to contain a group of targeted polynuclear aromatic hydrocarbons (PAH) at levels ranging from 10 to 2400 mg/kg. The soil extracts contained target PAH at levels ranging from 12 000 - 34 000 mg/kg. Dermal penetration rates of target PAH from the MGP tar-contaminated soils/soil extracts were determined experimentally through human skin using 3 H-benzo(a)pyrene (BaP) as a surrogate. Results from three MGP sites showed reductions of 2-3 orders of magnitude in PAH absorption through human skin from the most contaminated soils in comparison to the soil extracts. Reduction in PAH penetration can be attributed to PAH concentration and (soil) matrix properties. PAH dermal flux values are used to determine site-specific dermally absorbed dose (DAD) and chronic daily intake (CDI) which are essential terms required to estimate risk associated with human exposure to MGP tar and MGP tar-contaminated soils. 21 refs., 4 figs., 3 tabs

Tar removal from biomass gasification streams: processes and catalysts; Remocao do alcatrao de correntes de gaseificacao de biomassa: processos e catalisadores

Energy Technology Data Exchange (ETDEWEB)

Quitete, Cristina P.B. [Centro de Pesquisa e Desenvolvimento Leopoldo Americo Miguez de Mello (CENPES/PETROBRAS), Rio de Janeiro, RJ (Brazil). Processos de Conversao de Biomassa; Souza, Mariana M.V.M., E-mail: mmattos@eq.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Centro de Tecnologia. Escola de Quimica

2014-07-01

Biomass gasification is a technology that has attracted great interest in synthesis of biofuels and oxo alcohols. However, this gas contains several contaminants, including tar, which need to be removed. Removal of tar is particularly critical because it can lead to operational problems. This review discusses the major pathways to remove tar, with a particular focus on the catalytic steam reforming of tar. Few catalysts have shown promising results; however, long-term studies in the context of real biomass gasification streams are required to realize their potential. (author)

A Primer on Alberta’s Oil sands Royalties

Directory of Open Access Journals (Sweden)

Sarah Dobson

2015-12-01

Full Text Available Fulfilling its campaign promise, the new NDP government announced a review of Alberta’s royalty framework in June 2015. The province receives royalty revenue from three main sources – natural gas, crude oil, and oil sands. Since the 2009-10 fiscal year the largest contributor to Alberta’s royalty revenues has been the oil sands. If you want a sense of how important oil sands royalties have been for Alberta’s finances, consider this: In the 2014–15 fiscal year, the government collected just over $5 billion from oil sands royalties. These royalties covered over 10 per cent of the province’s operational expenses of $48.6 billion in the same fiscal year. Over the last six fiscal years the oil sands have contributed an average of 10 per cent of revenues to provincial coffers. This makes oil sands royalties the fourth largest contributor behind personal income taxes (23 per cent, federal transfers (13 per cent and corporate income taxes (11 per cent. But how many Albertans really understand how the royalty system works? What do we mean when we say “royalty”? How does the Alberta Government calculate royalties on oil sands producers? If the system is going to change, it’s important that Albertans understand how the current system works. That is what this paper is designed to do. For Albertans to properly judge the impact of new policy, they need a solid understanding of the current policy environment. We all know that oil prices have dropped and oil sands producers are losing profitability. As such, changes to the royalty system could have a deep and profound impact on the sector. Here are some of the issues this primer will study: • Pre-payout projects vs. post-payout projects, in other words, the classification of projects for royalty purposes based on whether the cumulative costs of a project exceed its cumulative revenues • Monthly payment of royalties vs. annual payment • Understanding the unit price of bitumen and how that

Human papillomavirus and tar hypothesis for squamous cell cervical ...

Indian Academy of Sciences (India)

2010-08-09

Aug 9, 2010 ... Keywords. Cervical cancer; co-factors; human papillomavirus; tar-based vaginal douche; tobacco smoke; wood smoke. Author Affiliations. Christina Bennett1 Allen E Kuhn2 Harry W Haverkos3. Indiana University School of Medicine, Indianapolis, Indiana 46202-5149, USA; Suite 300, Hamilton Mason Road ...

Coal-tar-based sealcoated pavement: A major PAH source to urban stream sediments

International Nuclear Information System (INIS)

Witter, Amy E.; Nguyen, Minh H.; Baidar, Sunil; Sak, Peter B.

2014-01-01

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. -- Highlights: • Total PAH concentrations were measured at 35 sites along an urbanizing land-use gradient. • PAH concentrations increased with increasing urban land-use. • Urban land-use metrics were measured at three spatial scales using GIS. • PAH assemblages indicate coal-tar-based sealcoat is a major urban PAH source. • PAH assemblages indicate coke-oven emissions are an important rural PAH source. -- Coal-tar-based sealcoated pavement is a major PAH source to urban freshwater stream sediments in south-central Pennsylvania, USA

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

Science.gov (United States)

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.

Gc/ms analysis of coal tar composition produced from coal

African Journals Online (AJOL)

Coal pyrolysis is one of the significant approaches for the comprehensive utilization ... planigraphy-GC/MS; therefore a satisfactory analytical result obtained, which .... Among the aliphatic group of the coal tar, the proportion of alkene is larger ...

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

Science.gov (United States)

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.

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

Science.gov (United States)

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

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

Science.gov (United States)

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.

Characterisation and catalytic upgrading of tars from coal-tyre hydropyrolysis

Energy Technology Data Exchange (ETDEWEB)

Mastral, A.M.; Murillo, R.; Callen, M.S.; Garcia, T. [Instituto de Carboquimica, Zaragoza (Spain)

1999-07-01

Tars from coal-tyre hydropyrolysis obtained in a swept fixed bed reactor were upgraded with catalysts. Upgraded oils were characterized, and naphtha, kerosene, gas oil, heavy gas oil and vacuum residue percentages were quantified. 7 refs., 3 tabs.

Guideline for Sampling and Analysis of Tar and Particles in Biomass Producer Gases. Version 3.3

Energy Technology Data Exchange (ETDEWEB)

Neeft, J.P.A.; Knoef, H.A.M.; Zielke, U.; Sjoestroem, K.; Hasler, P.; Simell, P.A.; Dorrington, M.A.; Thomas, L.; Abatzoglou, N.; Deutch, S.; Greil, C.; Buffinga, G.J.; Brage, C.; Suomalainen, M.

2002-07-01

This Guideline provides a set of procedures for the measurement of organic contaminants and particles in producer gases from biomass gasifiers. The procedures are designed to cover different gasifier types (updraft or downdraft fixed bed or fluidised bed gasifiers), operating conditions (0 - 900C and 0.6-60 bars) and concentration ranges (1 mg/m{sub n}{sup 3} to 300 g/m{sub n}{sup 3}). The Guideline describes a modular sampling train, and a set of procedures, which include: planning and preparation of the sampling, sampling and post-sampling, analysis, calculations, error analysis and reporting. The modular sampling train consists of 4 modules. Module 1 is a preconditioning module for isokinetic sampling and gas cooling. Module 2 is a particle collection module including a heated filter. Module 3 is a tar collection module with a gas quench (optionally by circulating a liquid), impinger bottles and a backup adsorber. Module 4 is a volume-sampling module consisting of a pump, a rotameter, a gas flow meter and pressure and temperature indicators. The equipment and materials that are required for procuring this modular sampling train are given in the Guideline. The sampling procedures consist of a description for isokinetic sampling, a leakage test prior to sampling, the actual sampling and its duration, how the equipment is cleaned after the sampling, and how the samples are prepared and stored. Analysis of the samples is performed via three procedures. Prior to these procedures, the sample is prepared by Soxhlet extraction of the tars on the particle filter and by collection of all tars in one bulk solution. The first procedure describes the weighing of the particle filter to obtain the concentration of particles in the biomass producer gas. The bulk tar solution is used for two purposes: for determination of gravimetric tar and for analysis of individual compounds. The second procedure describes how to determine the gravimetric tar mass from the bulk solution. The

Treatment of low-temperature tar-gas mixtures

Energy Technology Data Exchange (ETDEWEB)

Schick, F

1928-07-04

Process for the treating and conversion of low-temperature tar-vapor and gas mixtures in the presence of metals or metal oxides as well as bodies of large surface, without previous condensation of the liquid material to be treated, characterized by the treatment taking place with a mixture of desulfurizing metals and metal oxides which, if necessary, are precipitated on carriers and large surface nonmetal cracking catalysts, such as active carbon and silica gel.

Receiving demulsifying agent from the acid tar

Energy Technology Data Exchange (ETDEWEB)

Nikitina, A.A.; Belyaeva, A.S.; Kunakova, R.V. [FGBIHE ' Ufa State Academy of Economics and Services' , Ufa (Russian Federation); Movsumzade, E.M. [FGBIHE ' Ufa State Petroleum Technological Univ.' , Ufa (Russian Federation); Lapidus, A.L. [Russian Academy of Sciences, Moscow (Russian Federation). N.D. Zelinsky Institute of Organic Chemistry

2012-07-01

The processing of wastes of petrochemical production makes it possible to reduce the price of produced commodity of petroleum products substantially. Bitumen, fuel oils, tars and other mixture of heavy organic compounds are widely used in road construction, in paint and cable industries, manufacture of roofing materials, are used as boiler and furnace fuel, fuel for marine diesel engines, raw material for the production of modifying additives, fillers, surfaceactive substances, etc. (orig.)

Brown carbon in tar balls from smoldering biomass combustion

Science.gov (United States)

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...

Eastern Scheldt Sand, Baskarp Sand No. 15

DEFF Research Database (Denmark)

Andersen, A. T; Madsen, E. B.; Schaarup-Jensen, A. L.

The present data report contains data from 13 drained triaxial tests, performed on two different sand types in the Soil Mechanics Laboratory at Aalborg University in March, 1997. Two tests have been performed on Baskarp Sand No. 15, which has already ken extensively tested in the Soil Mechanics...... Laboratory. The remaining 11 triaxial tests have ben performed on Eastern Scheldt Sand, which is a material not yet investigated at the Soil Mechanics Laboratory. In the first pari of this data report, the characteristics of the two sand types in question will be presented. Next, a description...... will described. In this connection, the procedure for preparation of the soil specimens will be presented, and the actual performance of the tests will be briefly outlined. Finally, the procedure for processing of the measurements from the laboratory in order to obtain usable data will be described. The final...

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

International Nuclear Information System (INIS)

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

2004-01-01

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

Projections of energy requirements and their implications

International Nuclear Information System (INIS)

Hogroian, P.

1978-01-01

The subject is covered in sections, entitled as shown. Numerical data are indicated in parenthesis. The record of nuclear power forecasting (estimates of the growth of world nuclear power, penetration of the electric power market by nuclear power); brief review of energy forecasting techniques and problems; some views of future world energy demand (estimates of world primary energy requirements); possible allocations of energy resources to needs (allocation of resources (oil, oil from tar sands, shale, natural gas, coal, coal to gasification, hydroelectricity, renewable resources, nuclear) to the world's primary energy needs in the year 2000); observations on the adequacy of energy resources; implications for nuclear energy (postulated growth of world nuclear power, annual fuel cycle requirements of the world, annual uranium requirements of the world). (U.K.)

Modelling and design of undercarriage components of large-scale earthmoving equipment in tar sand operations

Energy Technology Data Exchange (ETDEWEB)

Szymanski, J.; Frimpong, S.; Sobieski, R. [Alberta Univ., Edmonton, AB (Canada). Centre for Advanced Energy and Minerals Research

2004-07-01

This presentation described the fundamental and applied research work which has been carried out at the University of Alberta's Centre for Advanced Energy and Minerals Research to improve the undercarriage elements of large scale earthmoving equipment used in oil sands mining operations. A new method has been developed to predict the optimum curvature and blade geometry of earth moving equipment such as bulldozers and motor graders. A mathematical relationship has been found to approximate the optimum blade shape for reducing cutting resistance and fill resistance. The equation is a function of blade geometry and soil properties. It is the first model that can mathematically optimize the shape of a blade on earth moving equipment. A significant saving in undercarriage components can be achieved from reducing the amount of cutting and filling resistance for this type of equipment working on different soils. A Sprocket Carrier Roller for a Tracked Vehicle was also invented to replace the conventional cylindrical carrier roller. The new sprocket type carrier roller offers greater support for the drive track and other components of the undercarriage assembly. A unique retaining pin assembly has also been designed to detach connecting disposable wear parts from earthmoving equipment. The retaining pin assembly is easy to assemble and disassemble and includes reusable parts. 13 figs.

Sand Needs and Resources Offshore New York

Science.gov (United States)

Lashley, J. M.; Flood, R. D.; White, M.; Bokuniewicz, H.; Hinrichs, C.; Wilson, R. E.

2016-02-01

"Superstorm" Sandy (October, 2012) accentuated the persistent problem of coastal erosion on New York's ocean coast. The New York state Department of State in cooperation with the Bureau of Ocean Energy Management has initiated further identification and assessment of marine sand reserves required to improve the resiliency of coastal communities and the maintenance of coastal habitats. The historical demand for beach nourishment has been about 1.5 million cubic meters per year, but sea level rise and the occurrence of extreme conditions may increase the demand to over 5 million cubic meters annually. Forty-four historical and proposed borrow sites have been delineated. This inner shelf is both sand rich and data rich. Geophysical and geological data has been compiled and reassessed to support identification, characterization, and delineation of sand resources for potential use in future coastal restoration, beach nourishment, and/or wetland restoration efforts. The South Shore of Long Island is composed in part by the Fire Island National Seashore. Holocene sand ridges extending at an oblique angle to the cross shore in the seaward direction. Borrow pits among the sand ridges, excavated were apparent in the most recent surveys and it appears that natural replenishment of offshore borrow areas has been occurring although the rates need to be determined in order to assess their sustainability. Not only is the area one of intense societal attention, but the use of this resource for coastal resilience must fit into a diverse framework marine spatial planning including not only traditional components, like commercial fishing, but also new factors like the siting of offshore wind-farms. To extend this assessment will include a recent survey, sponsored by the Bureau of Ocean Energy Management and the New York Department of State, providing approximately 700 km of geophysical survey lines located between 3 and 9 nautical miles offshore, and 46 geotechnical samples

ANALYSIS OF MEASURED AND MODELED SOLAR RADIATION AT THE TARS SOLAR HEATING PLANT IN DENMARK

DEFF Research Database (Denmark)

Tian, Zhiyong; Perers, Bengt; Furbo, Simon

2017-01-01

, such as solar radiation, inlet and outlet temperature for the solar collector field, flow rate and pressure, ambient temperature, Wind speed and wind direction were measured. Global horizontal radiation, direct normal irradiation (DNI) and total radiation on the tilted collector plane of the flat plate...... collector field have been measured in Tars solar heating plant. To determine the accuracy of modeled and measured solar radiation in Tars solar heating plant, monthly comparisons of measured and calculated radiation using 6 empirical models have been carried out. Comparisons of measured and modeled total......A novel combined solar heating plant with tracking parabolic trough collectors (PTC) and flat plate collectors (FPC) has been constructed and put into operation in Tars, 30 km north of Aalborg, Denmark in August 2015. To assess the operation performance of the plant, detailed parameters...

Seasonal geomorphic processes and rates of sand movement at Mount Baldy dune in Indiana, USA

Science.gov (United States)

Kilibarda, Zoran; Kilibarda, Vesna

2016-12-01

Winds are very strong, frequent, and have high energy (annual DP ∼800 VU) along the southern shores of Lake Michigan, allowing the coexistence of fixed and active dunes. Six years (2007-13) of monitoring Mount Baldy in the Indiana Dunes National Lakeshore reveals that this is the most active coastal dune in the Great Lakes region. This paper documents aeolian processes and changes in the dune's morphology that occur temporarily, following storms, or seasonally, due to weather (climate) variations. Most of the sand transport in this area takes place during strong storms with gale force (>17.5 m/s) winds, which occur in the autumn and winter months. A single storm, such as the October 28-31, 2013 event, can contribute 25% of the annual sand transport and dune movement inland. In its most active year (June 1, 2011 through May 31, 2012), Mount Baldy moved inland on average 4.34 m, with a maximum of 6.52 m along the blowout's axis (155° azimuth). During this particularly active season, there were six storms with sustained gale force winds, winter air temperatures were warmer than average, and shelf ice on Lake Michigan lasted only one day. The dune is least active during the summer season, when the winds are weakest. The late fall and winter winds are the strongest. But in a typical year, most of the dune's advance inland takes place during the spring thaw when sand is released from over-steepened and lumpy slip face, allowing it to avalanche to the toe of the slip face. However, with a warming air temperatures, a reduction in the duration of winter shelf ice, and rising Lake Michigan levels, the annual rates of sand transport and dune movement may increase. The recent Mount Baldy management strategy, which includes planting vegetation and installing wind barriers on the dune's stoss side in an effort to fix the dune and stop its further movement inland, may potentially cause the destruction of the mobile sand, open dune habitat, resulting in the extinction of rare

Parallels between playbacks and Pleistocene tar seeps suggest sociality in an extinct sabretooth cat, Smilodon

OpenAIRE

Carbone, Chris; Maddox, Tom; Funston, Paul J.; Mills, Michael G.L.; Grether, Gregory F.; Van Valkenburgh, Blaire

2008-01-01

Inferences concerning the lives of extinct animals are difficult to obtain from the fossil record. Here we present a novel approach to the study of extinct carnivores, using a comparison between fossil records (n=3324) found in Late Pleistocene tar seeps at Rancho La Brea in North America and counts (n=4491) from playback experiments used to estimate carnivore abundance in Africa. Playbacks and tar seep deposits represent competitive, potentially dangerous encounters where multiple predators ...

Traditional African Religions (TARs): on HIV/AIDS, health and ...

African Journals Online (AJOL)

This is because the moral guidance put forward by. African religions is underestimated; hence making HIV/AIDS more of a moral problem. Rethinking the dialogue with TARs, will help in setting appropriate means of enhancing health in a broad sense and living in human dignity in Africa. Mtafiti Mwafrika Vol. 15 2005: pp.

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

Science.gov (United States)

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.

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

Science.gov (United States)

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.

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

Science.gov (United States)

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.

Sulfur biogeochemistry of oil sands composite tailings

Energy Technology Data Exchange (ETDEWEB)

Warren, Lesley; Stephenson, Kate [Earth Sciences, McMaster University (Canada)], email: warrenl@mcmaster.ca; Penner, Tara [Syncrude Environmental Research (Canada)

2011-07-01

This paper discusses the sulfur biogeochemistry of oil sands composite tailings (CT). The Government of Alberta is accelerating reclamation activities on composite tailings. As a CT pilot reclamation operation, Syncrude is currently constructing the first freshwater fen. Minor unpredicted incidents with H2S gas released from the dewatering process associated with these reclamations have been reported. The objective of this study is to ascertain the connection between microbial activity and H2S generation within CT and to assess the sulfur biogeochemistry of untreated and treated (fen) CT over seasonal and annual timescales. The microbial geochemical interactions taking place are shown using a flow chart. CT is composed of gypsum, sand, clay and organics like naphthenic acids and bitumen. Sulfur and Fe cycling in mining systems and their microbial activities are presented. The chemistry and the processes involved within CT are also given along with the results. It can be said that the diverse Fe and S metabolizing microorganisms confirm the ecology involved in H2S dynamics.

How do different cigarette design features influence the standard tar yields of popular cigarette brands sold in different countries?

Science.gov (United States)

O'Connor, R J; Hammond, D; McNeill, A; King, B; Kozlowski, L T; Giovino, G A; Cummings, K M

2008-09-01

To examine the associations among cigarette design features and tar yields of leading cigarette brands sold in the United States, Canada, Australia and the United Kingdom. Government reports and numbers listed on packs were used to obtain data on International Organization for Standardization (ISO)/Federal Trade Commission (FTC) yields for the tar of 172 cigarette varieties sold in the United States, Canada, Australia and the United Kingdom. We used standardised methods to measure the following 11 cigarette design parameters: filter ventilation, cigarette pressure drop, filter pressure drop, tobacco rod length, filter length, cigarette diameter, tipping paper length, tobacco weight, filter weight, rod density and filter density. Filter ventilation was found to be the predominant design feature accounting for the variations between brands in ISO/FTC tar yields in each of the four countries. After accounting for filter ventilation, design parameters such as overwrap length, tobacco weight and rod density played comparatively minor roles in determining tar yields. Variation in ISO/FTC tar yields are predicted by a limited set of cigarette design features, especially filter ventilation, suggesting that governments should consider mandatory disclosure of cigarette design parameters as part of comprehensive tobacco product regulations.

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

Science.gov (United States)

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.

The tar sands of the USA : with permits now in hand, a Calgary company is a cash injection away from producing oil from America's first oilsands mine

Energy Technology Data Exchange (ETDEWEB)

Jaremko, D.

2010-06-15

A Canadian company has recently received approval to develop large oil sands mining operations in Utah. Earth Energy Resources is now raising the finances required to commercialize its operations in the state. Utah's oil sands reserves are currently estimated at between 20 to 32 billion barrels. However, the impacts of oil sands operations are of concern to some environmental groups, who worry that Utah will become a duplicate of Alberta's Athabasca region. The planned project is a 2000 barrel-per-day pilot project. Regulators in Utah have received negative responses from the public after advertising the potential project in local newspapers, and demonstrations have been held in the state's capital. Oil sands are already being developed at 2 installations in Utah, with the bitumen currently being sold as asphalt products. The state is also home to significant oil shale reserves. Operators in the region plan to design compact, well-contained mines in order to maintain transportability. 3 figs.

Fresh tar (from biomass gasification) destruction with downstream catalysts: comparison of their intrinsic activity with a realistic kinetic model

Energy Technology Data Exchange (ETDEWEB)

Corella, J.; Narvaez, I.; Orio, A. [Complutense Univ. of Madrid (Spain). Dept. of Chemical Engineering

1996-12-31

A model for fresh tar destruction over catalysts placed downstream a biomass gasifier is presented. It includes the stoichio-metry and the calculation of the kinetic constants for the tar destruction. Catalysts studied include commercial Ni steam reforming catalysts and calcinated dolomites. Kinetic constants for tar destruction are calculated for several particle sizes, times- on-stream and temperatures of the catalyst and equivalence ratios in the gasifier. Such intrinsic kinetic constants allow a rigorous or scientific comparison of solids and conditions to be used in an advanced gasification process. (orig.) 4 refs.

Fresh tar (from biomass gasification) destruction with downstream catalysts: comparison of their intrinsic activity with a realistic kinetic model

Energy Technology Data Exchange (ETDEWEB)

Corella, J; Narvaez, I; Orio, A [Complutense Univ. of Madrid (Spain). Dept. of Chemical Engineering

1997-12-31

A model for fresh tar destruction over catalysts placed downstream a biomass gasifier is presented. It includes the stoichio-metry and the calculation of the kinetic constants for the tar destruction. Catalysts studied include commercial Ni steam reforming catalysts and calcinated dolomites. Kinetic constants for tar destruction are calculated for several particle sizes, times- on-stream and temperatures of the catalyst and equivalence ratios in the gasifier. Such intrinsic kinetic constants allow a rigorous or scientific comparison of solids and conditions to be used in an advanced gasification process. (orig.) 4 refs.

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

Science.gov (United States)

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

2015-11-01

China is home to the greatest number of smokers as well as 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. 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 to 2012. 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 characterised using descriptive statistics, correlations and generalised estimating equations to observe changes in brand varieties over time. 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 yield overall were ventilation and per-cigarette tobacco weight, while for nicotine tobacco moisture was also an independent predictor of yield. 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 behaviours that would begin to reduce the health burden of tobacco in China, and so should be prohibited. 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/

Contemporary sand wedge development in seasonally frozen ground and paleoenvironmental implications

Science.gov (United States)

Wolfe, Stephen A.; Morse, Peter D.; Neudorf, Christina M.; Kokelj, Steven V.; Lian, Olav B.; O'Neill, H. Brendan

2018-05-01

Contemporary sand wedges and sand veins are active in seasonally frozen ground within the extensive discontinuous permafrost zone in Northwest Territories, Canada. The region has a subarctic continental climate with 291 mm a-1 precipitation, -4.1 °C mean annual air temperature, warm summers (July mean 17.0 °C), and cold winters (January mean -26.6 °C). Five years of continuous observations indicate that interannual variation of the ground thermal regime is dominantly controlled by winter air temperature and snow cover conditions. At sandy sites, thin snow cover and high thermal conductivity promote rapid freezing, high rates of ground cooling, and low near-surface ground temperatures (-15 to -25 °C), resulting in thermal contraction cracking to depths of 1.2 m. Cracking potentials are high in sandy soils when air temperatures are air temperatures are ≤-17 °C, and snow cover is conditions in peatlands maintain permafrost, but thermal contraction cracking does not occur because thicker snow cover and the thermal properties of peat prolong freezeback and maintain higher winter ground temperatures. A combination of radiocarbon dating, optical dating, and stratigraphic observations were used to differentiate sand wedge types and formation histories. Thermal contraction cracks that develop in the sandy terrain are filled by surface (allochthonous) and/or host (autochthonous) material during the thaw season. Epigenetic sand wedges infilled with allochthonous sand develop within former beach sediments beneath an active eolian sand sheet. Narrower and deeper syngenetic wedges developed within aggrading eolian sand sheets, whereas wider and shallower antisyngenetic wedges developed in areas of active erosion. Thermal contraction cracking beneath vegetation-stabilized surfaces leads to crack infilling by autochthonous host and overlying organic material, with resultant downturning and subsidence of adjacent strata. Sand wedge development in seasonally frozen ground

Annual Report 1999

International Nuclear Information System (INIS)

1999-01-01

Suncor is a Canada-based integrated oil company with over $ 5.2 billion in assets. It produces 142,800 barrels of oil equivalent per day. There are four major business areas within Suncor: (1) oil sands - produces and markets custom-blended refinery stocks and transportation fuel from its oil sands mining and upgrading facilities at Fort McMurray, Alberta; (2) the Exploration and Production arm which explores, acquires, develops and produces oil and natural gas in western Canada and markets its production throughout North America; (3) Sunoco, Suncor's refining and marketing operation, with a major refinery in Sarnia, Ontario, and a network of more than 500 retail gasoline outlets throughout the province; and (4) International oil and In-situ operations, which focus on developing heavy oil and oil shale technologies that provide unique strategic advantages to Suncor on a global basis. This report records the company's progress during the 1999 fiscal year in terms of the company's priorities for long-term growth , i.e. to expand the oil sands, transfer expertise and technology from oil sands to new businesses, integrate downstream and upstream businesses, and focus on natural gas and alternative and renewable energy. The company is fully aware of the need for sustainable development and in its oil sands operations has in place a comprehensive Greenhouse Gas Management Plan that in fact affects the entire company. The goal is to remove one tonne of carbon dioxide for every tonne of carbon dioxide released into the atmosphere through management of own emissions, pursuing greenhouse gas offsets and supporting education and research. The company has scored some notable successes in all of the target areas, details of which are provided in this annual report. A statement of the company's financial state is also included, along with the company's goals for 2000

Perversities of Extreme Dependence and Unequal Growth in the TAR

NARCIS (Netherlands)

A.M. Fischer (Andrew Martín)

2007-01-01

textabstractThe official Chinese press recently came out with a series of articles reporting the latest statistics on the phenomenally rapid economic growth that has been taking place in the Tibet Autonomous Region (TAR) since the mid-1990s through sheer force of Central Government subsidies.

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

Science.gov (United States)

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.

Laboratory studies of dune sand for the use of construction industry in Sri Lanka

Science.gov (United States)

de Silva Jayawardena, Upali; Wijesuriya, Roshan; Abayaweera, Gayan; Viduranga, Tharaka

2015-04-01

With the increase of the annual sand demand for the construction industry the excessive excavation of river sand is becoming a serious environmental problem in Sri Lanka. Therefore, it is necessary to explore the possibility for an alternative to stop or at least to minimize river sand mining activities. Dune sand is one of the available alternative materials to be considered instead of river sand in the country. Large quantities of sand dunes occur mainly along the NW and SE coastal belt which belong to very low rainfall Dry Zone coasts. The height of dune deposits, vary from 1m to about 30 meters above sea level. The objective of this paper is to indicate some studies and facts on the dune sand deposits of Sri Lanka. Laboratory studies were carried out for visual observations and physical properties at the initial stage and then a number of tests were carried out according to ASTM standards to obtain the compressive strength of concrete cylinders and mortar cubes mixing dune sand and river sand in different percentages keeping a constant water cement ratio. Next the water cement ratio was changed for constant dune sand and river sand proportion. Microscopic analysis shows that the dune sand consist of 95 % of quartz and 5 % of garnet, feldspar, illmenite and other heavy minerals with clay, fine dust, fine shell fragments and organic matters. Grains are sub-rounded to angular and tabular shapes. The grain sizes vary from fine to medium size of sand with silt. The degree of sorting and particle size observed with dune sands are more suited with the requirement of fine aggregates in the construction industry. The test result indicates that dune sand could be effectively used in construction work without sieving and it is ideal for wall plastering due to its'-uniformity. It could also be effectively used in concrete and in mortars mixing with river sand. The best mixing ratio is 75% dune sand and 25% river sand as the fine aggregate of concrete. For mortar the mixing

Sand mining impacts on long-term dune erosion in southern Monterey Bay

Science.gov (United States)

Thornton, E.B.; Sallenger, Abby; Sesto, Juan Conforto; Egley, L.; McGee, Timothy; Parsons, Rost

2006-01-01

Southern Monterey Bay was the most intensively mined shoreline (with sand removed directly from the surf zone) in the U.S. during the period from 1906 until 1990, when the mines were closed following hypotheses that the mining caused coastal erosion. It is estimated that the yearly averaged amount of mined sand between 1940 and 1984 was 128,000 m3/yr, which is approximately 50% of the yearly average dune volume loss during this period. To assess the impact of sand mining, erosion rates along an 18 km range of shoreline during the times of intensive sand mining (1940–1990) are compared with the rates after sand mining ceased (1990–2004). Most of the shoreline is composed of unconsolidated sand with extensive sand dunes rising up to a height of 46 m, vulnerable to the erosive forces of storm waves. Erosion is defined here as a recession of the top edge of the dune. Recession was determined using stereo-photogrammetry, and LIDAR and GPS surveys. Long-term erosion rates vary from about 0.5 m/yr at Monterey to 1.5 m/yr in the middle of the range, and then decrease northward. Erosion events are episodic and occur when storm waves and high tides coincide, allowing swash to undercut the dune and resulting in permanent recession. Erosion appears to be correlated with the occurrence of El Niños. The calculated volume loss of the dune in southern Monterey Bay during the 1997–98 El Niño winter was 1,820,000 m3, which is almost seven times the historical annual mean dune erosion of 270,000 m3/yr. The alongshore variation in recession rates appears to be a function of the alongshore gradient in mean wave energy and depletions by sand mining. After cessation of sand mining in 1990, the erosion rates decreased at locations in the southern end of the bay but have not significantly changed at other locations.

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

Science.gov (United States)

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.

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

Directory of Open Access Journals (Sweden)

Wolfgang Blenau

2017-10-01

Full Text Available 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.

Natural radioactivity measurements in beach sand along the South East coast of Tamil Nadu, India

International Nuclear Information System (INIS)

Selvi, B.S.; Vijayakumar, B.; Ravi, P.M.

2017-01-01

Measurement of natural radioactivity in beach sand was carried out along the south east coast of Tamil Nadu, India, The activity concentrations of "2"3"8U, "2"3"2Th and "4"0K in beach sand ranged from 2 to 2,762 Bqkg"-"1 with a mean value of 236 Bq.kg"-"1, 7 to 30,872 Bqkg"-"1 with a mean value of 2,300 Bqkg"-"1 and 6.0 to 890 Bqkg"-"1 with a mean value of 85 Bqkg"-"1, respectively. The Radium Equivalent Activity, the external hazard index, the absorbed dose rate and the annual effective dose were assessed and compared with world average values. The results indicate that the absorbed dose rates range from 10 to 20506 nGyh"-"1 with mean value of 1545 nGy.h"-"1. The annual effective dose range between 0.01 and 25.15 mSvy"-"1, with the mean value of 1.90 mSvy"-"1. (author)

Assessing the effects of oil sands related ozone precursor emissions on ambient ozone levels in the Alberta oil sands region, Canada

Science.gov (United States)

Cho, Sunny; Vijayaraghavan, Krish; Spink, David; Cosic, Biljana; Davies, Mervyn; Jung, Jaegun

2017-11-01

A study was undertaken to determine whether, and the extent to which, increased ground-level ozone (O3) precursor emissions from oil sands development have impacted ambient air quality in the north-eastern Alberta, Canada, over the period 1998 to 2012. Temporal trends in emissions of O3 precursors (NOx and VOC) and ambient air concentrations of O3 precursors, and O3 were examined using the Theil-Sen statistical analysis method. Statistically significant correlations between NOx emissions and ambient NOx concentrations were found mainly near surface (open-pit) mining areas where mine fleets are a large source of NOx emissions. No statistically significant trends in the 4th highest daily maximum 8-hr average O3 at any of the continuous and passive ambient air monitoring stations were found. A significant long-term decrease in monthly averaged O3 is observed at some ambient monitoring sites in summer. A visual examination of long-term variations in annual NOx and VOC emissions and annual 4th highest daily maximum 8-hr O3 concentrations does not reveal any indication of a correlation between O3 concentrations and O3 precursor emissions or ambient levels in the study area. Despite a significant increase in oil sands NOx emissions (8%/yr), there is no statistically significant increase in long-term O3 concentrations at any of monitoring stations considered. This suggests that there is surplus NOx available in the environment which results in a titration of ambient O3 in the areas that have ambient monitoring. The limited ambient O3 monitoring data distant from NOx emission sources makes it impossible to assess the impact of these increased O3 precursor levels on O3 levels on a regional scale. As a precautionary measure, the increasing oil sands development O3 precursor emissions would require that priority be given to the management of these emissions to prevent possible future O3 ambient air quality issues.

Fontainebleau Sand

DEFF Research Database (Denmark)

Leth, Caspar Thrane

2006-01-01

The report is a summary of results from laboratory tests in the geotechncial research group on Fontainebleau sand.......The report is a summary of results from laboratory tests in the geotechncial research group on Fontainebleau sand....

Calcipotriol versus coal tar: a prospective randomized study in stable plaque psoriasis

Energy Technology Data Exchange (ETDEWEB)

Sharma, V.; Kaur, I.; Kumar, B. [Postgraduate Institute of Medicinal Education & Research, Chandigarh (India)

2003-10-01

Topical therapies are the first line of treatment for patients with stable plaque psoriasis (SPP) affecting a limited body surface area. Very few trials comparing newer agents, such as 0.005% topical calcipotriol, with conventional modes of therapy, such as coal tar ointment, have been reported. A prospective, right-left randomized, investigator-blinded study with a 12-week treatment period and an 8-week follow-up period was performed. It was found that 0.005% calcipotriol ointment produced a faster initial response and had better cosmetic acceptability in patients, although after a long period of treatment, i.e. 12 weeks, 5% coal tar ointment had comparable efficacy. There was no statistically significant difference in the relapse rates between the two modalities.

Use of advanced chemical fingerprinting in PAH source identification and allocation at a coal tar processing site

International Nuclear Information System (INIS)

Brown, J.S.; Boehm, P.D.; Douglas, G.S.

1995-01-01

Advanced chemical fingerprinting analyses were used to determine source allocation at a former coal tar processing facility which had been converted to a petroleum recycling site. Soil samples from the site had high petroleum hydrocarbon concentrations and elevated levels of polynuclear aromatic hydrocarbons (PAH). Comparisons of PAH distributions were used to differentiate the coal tar hydrocarbons from the petroleum hydrocarbons in soil samples. A more specific technique was needed to accurately allocate the contribution of the two sources to the observed PAH contamination in the soil. Petroleum biomarkers (steranes and triterpanes) which are present in crude oils and many refined petroleum products but are absent in coal tar were used to quantitatively allocate the source of the PAH contamination based on the relative ratio of the PAH to the biomarkers in soil samples. Using the resulting coal tar/petroleum source ratio the contribution of petroleum to the overall PAH contamination at the site was calculated. A multivariate statistical technique (principal component analysis or PCA) was used to provide an independent validation of the source allocation. The results of the source allocation provided a foundation for the site clean-up and remediation costs

The Karakum and Kyzylkum sand seas dynamics; mapping and palaeoclimatic interpretations

Science.gov (United States)

Maman, Shimrit; Blumberg, Dan G.; Tsoar, Haim; Porat, Naomi

2015-04-01

Sand seas are large basins in deserts that are mantled by wind-swept sand and that exhibit varying degrees of vegetation cover. Wilson (1973) was the first to globally map and classify sand seas. Beyond Wilson's maps, however, little research has been published regarding the Karakum and Kyzylkum sand seas of Central Asia. Wilson's maps delineate active ergs from inactive ergs based solely on precipitation. His assumption of annual average rainfall as a factor determining mobility vs. stability of sand seas is too simplistic and does not take into consideration other factors such as biogenic soil crusts and wind power, both of which are known to have major effects on the dynamics of sand dunes. Literature related to mapping and classifying the Central Asian ergs by remote sensing or sand sea classification state (stable/active) is lacking. Moreover, the palaeoclimatic significance of dunes in Central Asia is difficult to assess, as there has been few studies of dune stratigraphy and numerical ages are lacking. Optically stimulated luminescence (OSL) is a firm optical dating method that is used to determine the elapsed time since quartz grains were last exposed to sunlight, thus, their burial. Yet, absolute ages indicating mobilization and stabilization of these sands, are still inadequately known and are here under discussion. The broad concern of this research was to determine the dynamics of the Central Asian sand seas and study the palaeoclimatic changes that brought to their stabilization. As there are no reliable maps or aeolian discussion of these sands, establishment of a digital data base was initially conducted, focusing on identifying and mapping these sand seas. The vast area and inaccessibility make traditional mapping methods virtually impossible. A variety of space-borne imagery both optical and radar, with varying spectral and spatial resolutions was used. These images provided the basis for mapping sand distribution, dune forms, and vegetation cover

Topical coal tar alone and in combination with oral methotrexate in management of psoriasis : a retrospective analysis

Directory of Open Access Journals (Sweden)

Prasad PVS

1997-01-01

Full Text Available Thirty five patients admitted with psoriasis were analysed. 16 patients received 20% crude coal tar and 19 patients received 20% crude coal tar along with methotrexate in a weekly oral schedule (15mg/wk. After 4 weeks of therapy there was total clearence in 52.6% of the patients with combination therapy, whereas only 12.5% of the patients with conventional therapy achieved this.

Study of Black Sand Particles from Sand Dunes in Badr, Saudi Arabia Using Electron Microscopy

Directory of Open Access Journals (Sweden)

Haider Abbas Khwaja

2015-08-01

Full Text Available Particulate air pollution is a health concern. This study determines the microscopic make-up of different varieties of sand particles collected at a sand dune site in Badr, Saudi Arabia in 2012. Three categories of sand were studied: black sand, white sand, and volcanic sand. The study used multiple high resolution electron microscopies to study the morphologies, emission source types, size, and elemental composition of the particles, and to evaluate the presence of surface “coatings or contaminants” deposited or transported by the black sand particles. White sand was comprised of natural coarse particles linked to wind-blown releases from crustal surfaces, weathering of igneous/metamorphic rock sources, and volcanic activities. Black sand particles exhibited different morphologies and microstructures (surface roughness compared with the white sand and volcanic sand. Morphological Scanning Electron Microscopy (SEM and Laser Scanning Microscopy (LSM analyses revealed that the black sand contained fine and ultrafine particles (50 to 500 nm ranges and was strongly magnetic, indicating the mineral magnetite or elemental iron. Aqueous extracts of black sands were acidic (pH = 5.0. Fe, C, O, Ti, Si, V, and S dominated the composition of black sand. Results suggest that carbon and other contaminant fine particles were produced by fossil-fuel combustion and industrial emissions in heavily industrialized areas of Haifa and Yanbu, and transported as cloud condensation nuclei to Douf Mountain. The suite of techniques used in this study has yielded an in-depth characterization of sand particles. Such information will be needed in future environmental, toxicological, epidemiological, and source apportionment studies.

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

Energy Technology Data Exchange (ETDEWEB)

Peter C. Van Metre; Barbara J. Mahler; Jennifer T. Wilson [U.S. Geological Survey, Austin, TX (USA)

2009-01-15

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, 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.

Out on the tar sands mainline : mapping Enbridge's web of pipelines : a corporate profile of pipeline company Enbridge

Energy Technology Data Exchange (ETDEWEB)

Girard, R.; Davis, T.R. [Polaris Institute, Ottawa, ON (Canada)

2010-05-15

This document described Enbridge's operations, economic situation, political connections, and its social and environmental track record. It explored the social cost of operating refineries and pipelines in First Nations communities and the environment. It also raised concerns regarding future plans to open up Asian markets to oil sand crude via the Gateway pipeline. This profile included specific details on recurring pipeline leaks that have caused environmental damage; the ongoing expropriation of First Nations land; widespread political lobbying and influence in Canada and the United States; and interference in local community decision-making through financial contributions and projects. refs., tabs., figs.

Criteria for selection of dolomites and catalysts for tar elimination from biomass gasification gas. Kinetic constants

Energy Technology Data Exchange (ETDEWEB)

Corella, J; Narvaez, I; Orio, A [Madrid Univ. (Spain). Dept. of Chem. Eng.

1997-12-31

Calcined dolomites and commercial steam reforming catalysts are used downstream biomass gasifiers for hot catalytic raw gas cleaning. To further compare these solids under a rigorous basis, a reaction network and a kinetic model are presented. The apparent kinetic constant for the tar reduction is here proposed as a basis of comparison. Tar sampling and analysis, and the units used for the space-time in the catalytic reactor affect the kinetic constants observed. (author) (2 refs.)

Criteria for selection of dolomites and catalysts for tar elimination from biomass gasification gas. Kinetic constants

Energy Technology Data Exchange (ETDEWEB)

Corella, J.; Narvaez, I.; Orio, A. [Madrid Univ. (Spain). Dept. of Chem. Eng.

1996-12-31

Calcined dolomites and commercial steam reforming catalysts are used downstream biomass gasifiers for hot catalytic raw gas cleaning. To further compare these solids under a rigorous basis, a reaction network and a kinetic model are presented. The apparent kinetic constant for the tar reduction is here proposed as a basis of comparison. Tar sampling and analysis, and the units used for the space-time in the catalytic reactor affect the kinetic constants observed. (author) (2 refs.)

A proteomic study of TAR-RNA binding protein (TRBP-associated factors

Directory of Open Access Journals (Sweden)

Chi Ya-Hui

2011-02-01

Full Text Available Abstract Background The human TAR RNA-binding protein, TRBP, was first identified and cloned based on its high affinity binding to the small hairpin trans-activation responsive (TAR RNA of HIV-1. TRBP has more recently been found to be a constituent of the RNA-induced silencing complex (RISC serving as a Dicer co-factor in the processing of the ~70 nucleotide pre-microRNAs(miRNAs to 21-25 nucleotide mature miRNAs. Findings Using co-immunoprecipitation and protein-identification by mass spectrometry, we characterized intracellular proteins that complex with TRBP. These interacting proteins include those that have been described to act in protein synthesis, RNA modifications and processing, DNA transcription, and cell proliferation. Conclusions Our findings provide a proteome of factors that may cooperate with TRBP in activities such as miRNA processing and in RNA interference by the RISC complex.

Colorado River sediment transport: 2. Systematic bed‐elevation and grain‐size effects of sand supply limitation

Science.gov (United States)

Topping, David J.; Rubin, David M.; Nelson, Jonathan M.; Kinzel, Paul J.; Corson, Ingrid C.

2000-01-01

The Colorado River in Marble and Grand Canyons displays evidence of annual supply limitation with respect to sand both prior to [Topping et al, this issue] and after the closure of Glen Canyon Dam in 1963. Systematic changes in bed elevation and systematic coupled changes in suspended‐sand concentration and grain size result from this supply limitation. During floods, sand supply limitation either causes or modifies a lag between the time of maximum discharge and the time of either maximum or minimum (depending on reach geometry) bed elevation. If, at a cross section where the bed aggrades with increasing flow, the maximum bed elevation is observed to lead the peak or the receding limb of a flood, then this observed response of the bed is due to sand supply limitation. Sand supply limitation also leads to the systematic evolution of sand grain size (both on the bed and in suspension) in the Colorado River. Sand input during a tributary flood travels down the Colorado River as an elongating sediment wave, with the finest sizes (because of their lower settling velocities) traveling the fastest. As the fine front of a sediment wave arrives at a given location, the bed fines and suspended‐sand concentrations increase in response to the enhanced upstream supply of finer sand. Then, as the front of the sediment wave passes that location, the bed is winnowed and suspended‐sand concentrations decrease in response to the depletion of the upstream supply of finer sand. The grain‐size effects of depletion of the upstream sand supply are most obvious during periods of higher dam releases (e.g., the 1996 flood experiment and the 1997 test flow). Because of substantial changes in the grain‐size distribution of the bed, stable relationships between the discharge of water and sand‐transport rates (i.e., stable sand rating curves) are precluded. Sand budgets in a supply‐limited river like the Colorado River can only be constructed through inclusion of the physical

Isolation of biosurfactant-producing bacteria from the Rancho La Brea Tar Pits.

Science.gov (United States)

Belcher, Richard W; Huynh, Kelvin V; Hoang, Timothy V; Crowley, David E

2012-12-01

This research was conducted to identify culturable surfactant-producing bacterial species that inhabit the 40,000-year-old natural asphalt seep at the Rancho La Brea Tar Pits in Los Angeles, CA. Using phenanthrene, monocyclic aromatic hydrocarbons, and tryptic soy broth as growth substrates, culturable bacteria from the tar pits yielded ten isolates, of which three species of gamma-proteobacteria produced biosurfactants that accumulated in spent culture medium. Partially purified biosurfactants produced by these strains lowered the surface tension of water from 70 to 35-55 mN/m and two of the biosurfactants produced 'dark halos' with the atomized oil assay, a phenomenon previously observed only with synthetic surfactants. Key findings include the isolation of culturable biosurfactant-producing bacteria that comprise a relatively small fraction of the petroleum-degrading community in the asphalt.

Tritium profiles in Kalahari sands as a measure of rain water recharge

International Nuclear Information System (INIS)

Verhagen, B.T.; Smith, P.E.; McGeorge, I.; Dziembowski, Z.

1978-01-01

This paper attempts to relate recharge measurements in the Kalahari by tritium profiles in the unsaturated zone to isotopic, hydrochemical and hydrologic data from an underlying, semi-confined aquifer. Auger holes into the sand cover were drilled along a line of experimental deeper holes penetrating the saturated zone. A further line of auger holes was drilled into the dune sand cover of a control area. Variable moisture contents, apparently indepent of grain size distribution and indicating transients are observed in the different profiles. 3 H and 18 O measurements on the moisture contents allow for the identification of the 1962/63 bomb tritium rise and successive drier and wetter periods. Infiltration, or potential recharge as percentage of infiltration was found to be strongly dependent on the annual rainfall. The distribution of 14 C, 13 C, 3 H and chemistry in the shallower of two underlying aquifers leads to the consideration of three possible mechanisms of recharge. Arguments favouring vertical recharge are presented, which lead to possible extrapolations into the sand covered areas of the Kalahari in general. (orig.) [de

New generation expandable sand screens

OpenAIRE

Syltøy, Christer

2014-01-01

Master's thesis in Petroleum engineering This thesis aims to give a general insight into sand control and various sorts of sand control measures and applications of sand control tools. Special focus will be given to expandable sand screens – a technology which came about in the late 1990’s through the use of flexible, expandable tubulars as base pipe in sand screens. More specifically Darcy’s Hydraulic Endurance Screens, a compliant sand screen system using hydraulic activation, and the fu...

Phase-equilibria for design of coal-gasification processes: dew points of hot gases containing condensible tars. Final report

Energy Technology Data Exchange (ETDEWEB)

Prausnitz, J.M.

1980-05-01

This research is concerned with the fundamental physical chemistry and thermodynamics of condensation of tars (dew points) from the vapor phase at advanced temperatures and pressures. Fundamental quantitative understanding of dew points is important for rational design of heat exchangers to recover sensible heat from hot, tar-containing gases that are produced in coal gasification. This report includes essentially six contributions toward establishing the desired understanding: (1) Characterization of Coal Tars for Dew-Point Calculations; (2) Fugacity Coefficients for Dew-Point Calculations in Coal-Gasification Process Design; (3) Vapor Pressures of High-Molecular-Weight Hydrocarbons; (4) Estimation of Vapor Pressures of High-Boiling Fractions in Liquefied Fossil Fuels Containing Heteroatoms Nitrogen or Sulfur; and (5) Vapor Pressures of Heavy Liquid Hydrocarbons by a Group-Contribution Method.

Saltation of non-spherical sand particles.

Directory of Open Access Journals (Sweden)

Zhengshi Wang

Full Text Available 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.

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

Energy Technology Data Exchange (ETDEWEB)

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

1979-05-01

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.

Long vigil in Athabasca oil sands culminates in rapid expansion plans

Energy Technology Data Exchange (ETDEWEB)

1974-05-01

Great Canadian Oil Sands Ltd. needs to earn $40 million or more per year to get a reasonable return on the investment, vice president and general manager R.D. Humphreys told delegates at the Petroleum Accountants Society of W. Canada annual conference at Jasper Park Lodge. The conference then was ''the Alberta Oil Sands.'' Sun Oil Co. has taken no return yet, but has paid off the loans and taken shares in return so it owns nearly all the equity capital. The operation is not really breaking even at present, but should improve because GCOS is getting the full effect of the oil price increase under the original royalty agreement with the Alberta government. It is hoped that this will enable the company to recoup an accumulated deficit of more than $90 million. Money is the biggest problem for the current expansion designed to raise production to the authorized 65,000 bpd. Manpower is second and delivery of materials third. There is a lead time of 15 to 18 mo. on critical materials. Over the long term, tailings disposal is the greatest single problem facing all oil sands operators.

Assessment of natural radioactivity levels and identification of minerals in Brahmaputra (Jamuna) river sand and sediment, Bangladesh

International Nuclear Information System (INIS)

Khalil, Md. Ibrahim; Majumder, Ratan Kumar; Kabir, Md. Zafrul; Deeba, Farah; Khan, Md. Nazrul Islam; Ali, Md. Idris; Paul, Debasish; Haydar, Md. Abu; Islam, Syed Mohammad Azharul

2016-01-01

Distribution of the natural radionuclides ( 238 U, 232 Th, and 40 K) and their specific activities in sands and sediments of the Brahmaputra (Jamuna) river of Bangladesh together with mineral characteristics has been studied to assess the radiation levels as well as to develop a baseline database for comparison in the future in case of any change in the area under study due to anthropogenic activities. The radiological parameters of natural radioactivity were assessed calculating the radium equivalent activity, hazard index, the absorbed dose rate, and annual effective dose. The average activity concentrations of 226 Ra ( 238 U), 232 Th, and 40 K in sand and sediment were found to be 59 ± 2 and 60 ± 2 Bq/kg, 113 ± 5 and 135 ± 5 Bq/kg, and 983 ± 42 and 1002 ± 43 Bq/kg, respectively. The calculated average absorbed dose rate and annual effective dose were found to be 150 nGy/h and 0.18 mSv/year respectively. These high values are associated with mineral content of the sediment. X-ray diffraction peaks of sand and sediment samples identify quartz, feldspar, rutile, zircon, monazite, uranium fluoride, hematite, kyanite, and uranium arsenide minerals to be present in the samples. (author)

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

Science.gov (United States)

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 studies using a standardized smoking technique revealed a mean 25% lower tar yield from 3.95% than 1.77% MJ (p 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.

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

NARCIS (Netherlands)

Bogaard, E.H. van den; Bergboer, J.G.M.; Vonk-Bergers, M.; Vlijmen-Willems, I.M. van; Hato, S.V.; Valk, P.G. van der; Schroder, J.M.; Joosten, I.; Zeeuwen, P.L.J.M.; Schalkwijk, J.

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

Assessment of source material (U and Th) in exploration, mining, processing of zircon sand in Central Kalimantan

International Nuclear Information System (INIS)

Dedi Hermawan; Pandu Dewanto; Sudarto

2011-01-01

From 2004 to 2008, according to data released by the Commerce Department, the volume of zircon sand and concentrates exports has increased highly. One of many locations in Indonesia that widely available zircon sand is Kalimantan island. For example, Central Kalimantan Province in 2007 to 2008 exports about 51,000 tones up to 79,000 tones of zircon sand annually. The concentration of source material in the zircon sand is important to be known because the presence of natural radioactive U and Th in zircon sand has the potential radiation hazard. Therefore it is necessary to conduct an assessment the potential reserves related to the source material contained in the zircon sand and radiation safety that are applied in the process of mining or processing of zircon sand. In this paper the location of mining and processing of zircon sand is restricted to the province of Central Kalimantan. From the assessment obtained that source material which is carried by zircon sand export form the province of Central Kalimantan have the potential to exceed the limits set by the BAPETEN Chairman Decree No.9 of 2006 About the Implementation of the Additional Protocol to the Accountability System and Control of Nuclear Materials. In terms of compliance with radiation safety, required increased surveillance of K3 during mining, process / processing by the worker, supervisor / supervisors and regional management company to be able the achievement of compliance with the provisions of the management of materials and the safety of radiation sources based on national regulations (BAPETEN) and international. (author)

Sandscape - engaging people in Met Office science through sand sculpture

Science.gov (United States)

Liggins, Felicity; Dowell, Ellen; Wardley, Jamie; Jamieson, Claire

2017-04-01

In 2015, the Met Office's award-winning outreach programme, designed to inspire the next generation of scientists and engineers, delivered one of its most ambitious and creative activities to date. It explored how scientists and artists can come together to create an engaging experience for young people and families. This activity was called Sandscape. Sandscape is an interactive sand sculpture workshop exploring how weather and climate affect our health. Budding sand sculptors are shown how to fashion elaborate structures from sand and water - creating a landscape with bridges, skyscrapers, forests and factories. As they work, participants are encouraged by the scientists delivering the activity to reflect on what makes a healthy city, considering how the natural and built environments influence air quality and circulation and how this impacts our health. Topics discussed include urban heat islands, air pollution and dispersion modelling, pollen forecasting and predicting the wind-borne spread of animal diseases. Each hour long workshop culminates in a dramatic demonstration that uses dry ice to represent clean air circulating from mountains, along rivers and into cities. Here we present an overview of Sandscape, identify the strengths and challenges of such a collaborative, innovative and playful approach to public engagement and share the results of our evaluation. Sandscape was originally supported by the Met Office and the Wellcome Trust, and produced by Einstein's Garden in collaboration with the Met Office, scientists from the University of Exeter and sand sculptors from Sand in Your Eye. It was first presented in Einstein's Garden at Green Man festival 2015, an independent music and arts festival held annually in Wales, and has since been invited to run at the 2015 Bournemouth Arts By the Sea Festival and Teignmouth's TRAIL Sculpture Festival in the summer of 2016.

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

International Nuclear Information System (INIS)

Zakaria, Mohamad Pauzi; Okuba, Tomoaki; Takada, Hideshige

2001-01-01

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 offshore 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 analysed for hopanes and polycylic 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 cost 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 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 photo-oxidation. (Author)

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.

Science.gov (United States)

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.

Dissolution and transport of coal tar compounds in fractured clay-rich residuum

DEFF Research Database (Denmark)

Vulava, Vijay M.; McKay, Larry D.; Broholm, Mette Martina

2012-01-01

the importance of rapid dissolution and transport through the fracture networks. The concentrations continued to rise but did not reach the corresponding effective solubility limit in most cases. Compounds that were less soluble and those that were more susceptible to sorption or matrix diffusion eluted...... at a much slower rate. Analysis of contaminant concentrations in microcore residuum samples indicated that all 10 compounds had spread throughout the entire monolith and had diffused into the fine-grained matrix between fractures. These data suggest that the predominantly fine pore structure did not appear......We investigated the dissolution and transport of organic contaminants from a crude coal tar mixture in a monolith of fractured clay-rich residuum. An electrolyte solution was eluted through the residuum monolith containing a small emplaced source of coal tar under biologically inhibited and mildly...

A source mixing model to apportion PAHs from coal tar and asphalt binders in street pavements and urban aquatic sediments

Energy Technology Data Exchange (ETDEWEB)

Ahrens, M.J.; Depree, C.V. [National Institute of Water & Atmospheric Research, Hamilton (New Zealand)

2010-12-15

Present-day and more than 30 years old road and footpath pavements from Auckland, New Zealand were analysed for PAHs to test the hypothesis that coal tar based pavement binders contribute to unusually high PAH concentrations in adjacent stream and estuarine sediments Total PAH ({Sigma}{sub 28}PAH) concentrations in the dichloromethane-soluble fraction ('binder'), comprising 5-10% of pavement mass, were as high as 200 000 mg kg{sup -1}(10 000 mg kg{sup -1} in binder + aggregate) Older and deeper pavement layers were strongly pyrogenic, whereas pavement layers from recently sealed roads had a more petrogenic composition and more than 1000 times lower Sigma(28)PAH concentrations. Source identification analysis using three PAH isomer ratio pairs (benz(a)anthracene/(benz(a)anthracene + chrysene), benzo(a)pyrene/(benzo(a)pyrene + benzo(e)pyrene)), and indeno(1,2,3-cd)pyrene/(indeno(1,2,3-cd)pyrene + benzo(g,h,i)perylene) revealed low PAH (bitumen) pavements to have consistently lower isomer ratios than high PAH (coal tar) samples. A concentration-weighted mixing model, with coal tar and bitumen as source materials, explained more than 80% of the variance in isomer ratios and enveloped the entire PAH compositional and concentration range encountered PAH composition and concentrations in adjacent stream sediments ({gt} 15 mg kg{sup -1} dry weight) were consistent with diluted coal tar material as a principal PAH source. Due to the very high PAH concentrations of coal tar, a coal tar content of as little as 0.01% of total sediment mass can account for more than 90% of PAH concentrations in adjacent stream sediments.

Liquefaction resistance of calcareous sands

International Nuclear Information System (INIS)

Sandoval Vallejo, Eimar

2012-01-01

Calcareous sands are unique in terms of their origin, mineralogy, shape, fragility and intra particle porosity. This article presents results from an experimental program carried out to study the liquefaction resistance of a calcareous sand retrieved from Cabo Rojo at Puerto Rico. The experimental program included mineralogical characterization, index properties, and undrained cyclic triaxial tests on isotropically consolidated reconstituted samples. Due to the large variation in the calcareous sand properties, results are compared with previous researches carried out on other calcareous sands around the world. Results showed a wide range in the liquefaction resistance of the studied calcareous sands. Cabo Rojo sand experienced greater liquefaction resistance than most of the calcareous sands used for comparison. Important differences in the excess pore pressure generation characteristics were also found.

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

Science.gov (United States)

2010-10-01

...) 48 CFR chapter 12 is maintained by the SPE through the TAR/TAM change process. This process consists... (C) To issue guidance which may be effective for a period of 1 year or less. (ii) Each TN will expire...

GC/MS analysis of coal tar composition produced from coal pyrolysis

African Journals Online (AJOL)

Coal tar is a significant product generated from coal pyrolysis. A detailed analytical study on its composition and chemical structure will be of great advantage to its further processing and utilization. Using a combined method of planigraphy-gas chromatograph/mass spectroscopy (GC/MS), this work presents a composition ...

Low Temperature Particle Filtration of Wood Gas with Low Tar Content

DEFF Research Database (Denmark)

Hindsgaul, Claus; Henriksen, Ulrik Birk; Bentzen, Jens Dall

2002-01-01

Baghouse filters and cartridge filters were tested online with wood gas from a two stage down draft gasifier. The gas contained soot and very low levels (10-30 mg/Nm³) of tar. Particle collection efficiencies were above 95%. Continuous operation with cheap self cleaning baghouse filters were test...

Western Gas Sands Project status report

Energy Technology Data Exchange (ETDEWEB)

Atkinson, C.H.

1978-11-30

Progress of government-sponsored projects directed toward increasing gas production from the low-permeability gas sands of the western United States is summarized. A Technology Implementation Plan (TIP) meeting was held at the CER office in Las Vegas, Nevada, October 16--19 to initiate the implementation phase of the Enhanced Gas Recovery (EGR) working group activities. A WGSP Logging Program meeting was conducted on October 24, 1978, at CER offices to define the problems associated with logs in tight gas sands. CER personnel and the project manager attended a two-day course on the fundamentals of core and reservoir analysis in Denver, Colorado, and met with USGS personnel to discuss USGS work on the WGSP. A meeting was held to discuss a contract for coring a Twin Arrow well on the Douglas Creek Arch, Colorado. CER Corporation personnel attended the Geological Society of America Annual Meeting held in Toronto, Canada, October 23--27 and a Gas Stimulation Workshop at Sandia Laboratories in Albuquerque, New Mexico, October 11 and 12 to discuss recent mineback experiments conducted at the Nevada Test Site. Fiscal year 1979 projects initiated by USGS and the Energy Technology Centers and National Laboratories are progressing as scheduled. Mobil Research and Development Corporation fractured zone 8 of the F-31-13G well in Rio Blanco County, Colorado. Colorado Interstate Gas Company poured the concrete pad for the compresser expected to be delivered in December and were laying pipeline between the wells at month end. The Mitchell Energy well, Muse Duke No. 1 was flowing on test at a rate of 2,100 Mcfd and preparations proceeded to fracture the well on November 15 with approximately 1,000,000 gal of fluid and 3,000,000 lb of sand. Terra Tek completed laboratory analyses of cores taken from the Mitchell Energy well.

Acute toxicity of birch tar oil on aquatic organisms

Directory of Open Access Journals (Sweden)

M. HAGNER

2008-12-01

Full Text Available Birch tar oil (BTO is a by-product of processing birch wood in a pyrolysis system. Accumulating evidence suggests the suitability of BTO as a biocide or repellent in terrestrial environments for the control of weeds, insects, molluscs and rodents. Once applied as biocide, BTO may end up, either through run-off or leaching, in aquatic systems and may have adverse effects on non-target organisms. As very little is known about the toxicity of BTO to aquatic organisms, the present study investigated acute toxicity (LC50/EC50 of BTO for eight aquatic organisms. Bioassays with the Asellus aquaticus (crustacean, Lumbriculus variegatus (oligochaeta worm, Daphnia magna (crustacean, Lymnea sp. (mollusc, Lemna minor (vascular plant, Danio rerio (fish, Scenedesmus gracilis (algae, and Vibrio fischeri (bacterium were performed according to ISO, OECD or USEPA-guidelines. The results indicated that BTO was practically nontoxic to most aquatic organisms as the median effective BTO concentrations against most organisms were >150 mg L-1. In conclusion, our toxicity tests showed that aquatic organisms are to some extent, invariably sensitive to birch tar oil, but suggest that BTO does not pose a severe hazard to aquatic biota. We deduce that, unless BTOs are not applied in the immediate vicinity of water bodies, no special precaution is required.;

Annual energy reviews-1995

International Nuclear Information System (INIS)

Anon.

1996-01-01

The general demand and supply of energy in the world, and the circumstances of electric power, iron and steel, and transportation industries in Japan are reported. Regarding coal, the fundamentals and the trend of research and development related to coal, the trends of coal mining industry and coke, aromatic compound, tar, carbon and coal ash industries are reported. Regarding petroleum, the fundamentals and the trend of research and development related to petroleum, the trends of petroleum industry and petroleum refining and petrochemical industries are reported. Regarding gases, the trends of developing natural gas and liquefied natural gas, town gas and the production of synthetic gases are reported. Regarding nuclear power, the state of nuclear power stations, the establishment of nuclear fuel cycle and the research and development of the utilization of nuclear power are reported. Regarding natural energy, the state of utilizing solar energy, geothermal energy, wind energy and ocean energy is reported. The uses of oil sand and oil shale, biomass and waste, hydrogen and alcohol are reported. The theory of combustion, the trends of cogeneration and heat pumps, the trends of boilers, industrial furnaces, engines, and high efficiency electric power generation technologies are reported. The trends of environmental problems and waste problems and the preservation of atmospheric environment are reported. (K.I.)

MECHANICAL REGENERATION OF SAND WASTE

Directory of Open Access Journals (Sweden)

D. I. Gnir

2005-01-01

Full Text Available The experimental activation of the sand regenerator of the firm SINTO is carried out at ОАО “MZOO". It is shown that sand grains are cleared from films of binding agents, that allows to use the treated sand for preparation of agglutinant and core sands.

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

Energy Technology Data Exchange (ETDEWEB)

Suneel, V., E-mail: vasimallas@nio.org [CSIR-National Institute of Oceanography, Dona Paula, Goa 403004 (India); Vethamony, P., E-mail: mony@nio.org [CSIR-National Institute of Oceanography, Dona Paula, Goa 403004 (India); Naik, B.G., E-mail: bgnaik@nio.org [CSIR-National Institute of Oceanography, Dona Paula, Goa 403004 (India); Krishna, M.S., E-mail: moturi@nio.org [CSIR-National Institute of Oceanography, Regional Centre, Visakhapatnam, 530 017 (India); Jadhav, Lakshmikant, E-mail: lakshya87.0@gmail.com [CSIR-National Institute of Oceanography, Dona Paula, Goa 403004 (India)

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. - Highlights: • Multi-marker approach was effective in identifying the source of tar balls. • n-Alkane DRs show weathering effects even within the core of the tar ball. • Tar balls of the west coast of India since 2012 were derived from Bombay High crude. • Tanker-wash is not the only source of tar balls deposited on the beaches of Goa.

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

International Nuclear Information System (INIS)

Suneel, V.; Vethamony, P.; Naik, B.G.; Krishna, M.S.; Jadhav, Lakshmikant

2015-01-01

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. - Highlights: • Multi-marker approach was effective in identifying the source of tar balls. • n-Alkane DRs show weathering effects even within the core of the tar ball. • Tar balls of the west coast of India since 2012 were derived from Bombay High crude. • Tanker-wash is not the only source of tar balls deposited on the beaches of Goa

Population dynamics of the sand shiner (notropis stramineus) in non-wadeable rivers of Iowa

Science.gov (United States)

Smith, C.D.; Neebling, T.E.; Quist, M.C.

2010-01-01

The sand shiner (Notropis stramineus) is a common cyprinid found throughout the Great Plains region of North America that plays an important ecological role in aquatic systems. This study was conducted to describe population dynamics of sand shiners including age structure, growth, mortality, and recruitment variability in 15 non-wadeable rivers in Iowa. Fish were collected during June-August (2007-2008) using a modified Missouri trawl, a seine, and boat-mounted electrofishing. Scales were removed for age and growth analysis. A total of 3,443 fish was sampled from 15 populations across Iowa, of which 676 were aged. Iowa's sand shiner populations consisted primarily of age-1 fish (53% of all fish sampled), followed by age-2 fish (30%), age-0 fish (15%), and age-3 fish (2%). Sand shiners grew an average of 38.5 mm (SE = 5.7) during their first year, 13.8 mm (4.5) during their second year, and 9.0 mm (6.9) during their third year. Total annual mortality varied from 35.0% to 92.3% among populations with a mean of 77.9% (0.2). Incremental mortality rates were 84.5% (0.2) between age 1 and age 2, and 92.0% (0.1) between age 2 and age 3. Recruitment was highly variable, as indicated by a mean recruitment variation index of-0.12 (0.54). Overall, the sand shiner was characterized by relatively low mean age, fast growth, high mortality, and high recruitment variability. Indices of sand shiner population dynamics were poorly correlated with habitat characteristics.

Evaluation of different oxygen carriers for biomass tar reforming

DEFF Research Database (Denmark)

Mendiara, Teresa; Johansen, Joakim Myung; Utrilla, Rubén

2011-01-01

, in a concentration of 600–2000ppmv, was chosen as a tar model compound. Experiments were performed in a TGA apparatus and a fixed bed reactor. Four oxygen carriers (60% NiO/MgAl2O4 (Ni60), 40% NiO/NiAl2O4 (Ni40), 40% Mn3O4/Mg–ZrO2 (Mn40) and FeTiO3 (Fe)) were tested under alternating reducing/oxidizing cycles...

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

Science.gov (United States)

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).

Crushed rock sand – An economical and ecological alternative to natural sand to optimize concrete mix

Directory of Open Access Journals (Sweden)

Sanjay Mundra

2016-09-01

Full Text Available The study investigates the use of crushed rock sand as viable alternative to Natural River sand that is being conventionally used as fine aggregate in cement concrete. Various mix designs were developed for different grades of concrete based on IS, ACI and British codes using Natural River sand and crushed rock sand. In each case, the cube compressive strength test, and beam flexure tests were conducted. The results of the study show that, the strength properties of concrete using crushed rock sand are nearly similar to the conventional concrete. The study has shown that crushed stone sand can be used as economic and readily available alternative to river sand and can therefore help to arrest the detrimental effects on the environment caused due to excessive mining of river sand.

1999 Annual report -- Generating results

International Nuclear Information System (INIS)

2000-01-01

The Athabasca Oil Sands Trust was created in 1995 by Athabasca Oil Sand Investments Inc. acquiring the Province of Alberta's 11.74 per cent working interest in the Syncrude Project, providing the first modern day opportunity for direct public investment in Syncrude and oil sands development in northern Alberta. Syncrude operates major oil sands mines, a utilities plant and bitumen extraction and upgrading facilities at Mildred Lake, near Fort McMurray. In 1999, Syncrude produced a record 81.4 million barrels of Syncrude Sweet Blend (SSB), a light 32 degree API sweet crude oil, meeting about 12 per cent of Canada's crude oil requirements. The average 1999 price received by the Trust for Syncrude Sweet Blend was $ 26.04 ber barrel. More robust oil prices, record annual volumes of production averaging 26,000 barrels per day (The Trust's share of Syncrude production) and the lowest ever operating costs ($ 12.55 per barrel) combined to produce record earnings for the Trust of $ 82.6 million, or 60 cents per unit for the year. In 1997, Syncrude owners announced a $ 6.0 billion expansion plan that would double production to more than 150 million barrels per year by 2007. In October 1999, the owners reaffirmed their commitment to continue working toward the four-stage expansion plan and propose to increase production in 2000 to 92 million barrels per year and to 165 million barrels per year by 2008. With the anticipated start-up of the Aurora Mine in late May of 2000, the Trust expects Syncrude volumes in excess of 90 million barrels at an average cost of $12.25 per barrel in 2000. The Trust's share of the projected volume is 10.6 million barrels or 29,000 barrels per day. Based on commitment to continuing the expansion, and assuming that oil prices remain buoyant, the Trust expects to maintain distributions at or above 1999 levels. The annual report contains a detailed discussion of the expansion plans, management's discussion and analysis of operational and financial

Catalytic decomposition of biomass tars: Use of dolomite and untreated olivine

NARCIS (Netherlands)

Devi, L.; Ptasinski, K.J.; Janssen, F.J.J.G.; Paasen, van S.V.B.; Bergman, P.C.A.; Kiel, J.H.A.

2005-01-01

Although biomass is getting increased attention as a renewable energy source, one of the remaining problems still to be solved is the reduction of the high level of tar present in the product gas from gasification of biomass. The purpose of the present work is to study the activity of olivine and

Low Temperature Particle Filtration of Producer Gas with Low Tar Content

DEFF Research Database (Denmark)

Hindsgaul, Claus

This report describes the tests of different techniques for removing the particulates from producer gas from the 100 kW two-stage down-draft gasifier at DTU1 . The goal of the tests was to identify and implement methods to remove soot particles from producer gas with low tar content. During the f...

Fourth annual report 1991

International Nuclear Information System (INIS)

1991-01-01

The Independent Radiation Monitoring Scheme for Clwyd began its monitoring programme in Clwyd in 1988. This is the fourth report on the results of the radiation monitoring carried out within Clwyd. The historical reasons for the conception of the Radiation Monitoring Scheme are given in the First Annual Report together with the protocol of operation and detailed sampling and monitoring information. The fourth Annual Report identifies any changes in techniques that have occurred in the last twelve months together with the latest monitoring and analytical data. Samples of air, beach materials, coastal sand and silt, seaweed, meat, fish and milk were taken from various locations within the county. No significant charges in radiation levels were found when compared with data from previous years. The values have remained within the range currently being expected throughout the United Kingdom. (author)

Polycyclic aromatic hydrocarbons (PAHs) in a coal tar standard reference material - SRM 1597a updated

Energy Technology Data Exchange (ETDEWEB)

Wise, Stephen A.; Poster, Dianne L.; Rimmer, Catherine A.; Schubert, Patricia; Sander, Lane C.; Schantz, Michele M. [National Institute of Standards and Technology (NIST), Analytical Chemistry Division, Gaithersburg, MD (United States); Leigh, Stefan D. [National Institute of Standards and Technology (NIST), Statistical Engineering Division, Gaithersburg, MD (United States); Moessner, Stephanie [National Institute of Standards and Technology (NIST), Analytical Chemistry Division, Gaithersburg, MD (United States); GMP/Comparator Labs, Werthenstein Chemie AG, Industrie Nord, Schachen (Switzerland)

2010-09-15

SRM 1597 Complex Mixture of Polycyclic Aromatic Hydrocarbons from Coal Tar, originally issued in 1987, was recently reanalyzed and reissued as SRM 1597a with 34 certified, 46 reference, and 12 information concentrations (as mass fractions) for polycyclic aromatic hydrocarbons (PAHs) and polycyclic aromatic sulfur heterocycles (PASHs) including methyl-substituted PAHs and PASHs. The certified and reference concentrations (as mass fractions) were based on results of analyses of the coal tar material using multiple analytical techniques including gas chromatography/mass spectrometry on four different stationary phases and reversed-phase liquid chromatography. SRM 1597a is currently the most extensively characterized SRM for PAHs and PASHs. (orig.)

Durability and regeneration of catalysts of the iron family in hydrogenation of low-temperature tar

Energy Technology Data Exchange (ETDEWEB)

Funasaka, W; Yokogawa, C; Hayashi, K; Kawamura, T; Fujita, H; Suga, S

1949-01-01

The low-temperature tar consisting of neutral and acidic oils has been reduced under atmospheric pressure between 400/sup 0/ and 500/sup 0/ by using catalysts prepared from Fe-Cr-kieselguhr, yellow ocher, and other material. When the reduction was performed at 480/sup 0/ with the yellow ocher from Niwasaka, Fukushima Prefacture, Japan, the low-temperature tar was easily converted to neutral and light oils and the catalysts could be regenerated by repeated baking and reduction. It is concluded that the commercialization of this reduction process is possible by using a cycle (each takes 20 minutes) composed of catalytic reaction, baking, and reduction of the catalysts.

Rheological Characterization of Green Sand Flow

DEFF Research Database (Denmark)

Jabbaribehnam, Mirmasoud; Spangenberg, Jon; Hovad, Emil

2016-01-01

The main aim of this paper is to characterize experimentally the flow behaviour of the green sand that is used for casting of sand moulds. After the sand casting process is performed, the sand moulds are used for metal castings. The rheological properties of the green sand is important to quantif...

Main component analysis of nuclear magnetic resonance /sup 1/H and /sup 13/C quantitative spectra of hydrogenation products of tars from Kansk-Achinsk Achinsk and Cheremkhovsk coals

Energy Technology Data Exchange (ETDEWEB)

Kushnarev, D.F.; Polonov, V.M.; Donskikh, V.I.; Rokhina, E.F.; Kalabin, G.A.

1986-03-01

Possibility is discussed of examining nuclear magnetic resonance /sup 1/H and /sup 13/C quantitative spectra of coal tar hydrogenation products using main component factorial analysis and applying special mathematical methods of processing experimental data. Nuclear magnetic resonance spectra of hydrogenation products of low temperature Cheremkhovsk coal carbonization tar and rapid pyrolysis Kansk-Achinsk coal tar were obtained on a WP-200SY (Bruker) spectrometer at 50.3 and 200.1 MHz, respectively. Data processing was carried out on an ODRA-1304 computer. Comparative correlation of parameters are given of tars and hydrogenation products which consist of hydrogenation of aromatic cycles and destruction of alkyl substituents, and factorial loads on structural parameters of tar hydrogenation products. 11 references.

Natural radioactivity in sand beaches of Guarapari, Espirito Santo state, Brazil: a comparative study

International Nuclear Information System (INIS)

Vasconcelos, Danilo C.; Pereira, Claubia; Oliveira, Arno H.; Santos, Talita O.; Reis, Patricia L.

2011-01-01

Using gamma ray spectrometry, the activity concentration of naturally occurring radionuclides 226 Ra, 232 Th, and 40 K was determined in sand beaches samples from different areas in Guarapari, Espirito Santo state, from Brazil. The absorbed dose rates and annual effective dose were calculated and the results are compared with the internationally accepted values as well as others high background radiation areas (HBRAs).The activity concentration of the 232 Th in Areia Preta as well as the absorbed dose rates and annual effective dose were higher than the others regions compared. The results show that Areia Preta in Guarapari has higher background found in beaches in world. (author)

The Alberta oil sands story

Energy Technology Data Exchange (ETDEWEB)

1974-01-01

This report serves as a detailed introduction to the Alberta oil sands and their development. It includes a description of the oil sands deposits, an outline of crude bitumen recovery and upgrading processes, the role of Alberta Energy Company in oil sands development, environmental aspects, manpower requirements for oil sands development, research needs, and further oil sands projects. Presently proven recoverable reserves in the oil sands amount to 26.5 billion bbl of synthetic crude. Production from the Syncrude plant (125,000 bbl/d capacity) is expected to begin in 1977, followed by a Shell Canada operation around 1980. The provincial government will participate in the oil sand industry through its joint venture participation in Syncrude and its 50% share in Alberta Energy Company; the latter company participates in related aspects of the Syncrude project, such as pipelines. The result of Alberta's participation in the industry will mean that, directly or indirectly, the province will realize 60% of the total profits. The job creation potential of oil sands projects is estimated to be extensive, with a direct and indirect work force supported by oil sands activities possibly reaching 180,000 persons by the year 2000. Research needs have been identified, particularly in the area of in-situ thermal recovery technology, and the creation of the Alberta Oil Sands Technology and Research Authority has been authorized in order to meet these needs. Although current reserves are sufficient to support 20-30 synthetic crude plants, a number of factors will limit expansion of the industry. 8 figs., 5 tabs.

Easing the capacity crunch : infrastructure requirements to support rapidly developing oil sands

International Nuclear Information System (INIS)

Zupan, L.

2003-01-01

Through annual consultation with its customers, Enbridge develops a supply and demand forecast which forms the basis for the company's development. It is complex to develop the appropriate pipeline infrastructure to support resource development, based on the significant forecast growth in supply in Alberta from oil sands and the limited traditional markets. The largest crude oil pipeline serving the oil sands industry in Alberta is owned and operated by Enbridge. The first customer was Suncor, followed by PetroCanada and EnCana. In 2002, a pipeline concept was developed by Enbridge to provide a link to Edmonton via a new large diameter pipeline. The mainline system which originates in Edmonton is expected to evolve and grow as oil sands production comes on line. The completion of Terrace Phase III expansion is one of the priorities for Enbridge in 2003. Other projects involve the extension of one of its lines from Mokena to Chicago, the segregation of batches on the system to improve quality of its deliveries, and extension and expansion into new markets. Shipper support will determine the scale of these developments. The Canadian Association of Petroleum Producers (CAPP) has undergone a market study, as has Enbridge (Oil Sands Markets Study) in an effort to better understand markets and potential markets. It will assist in the determination of which pipeline infrastructure requires expansion, as well as the extent of infrastructure required to support new markets. tabs., figs

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

Science.gov (United States)

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.

Compressive behavior of fine sand.

Energy Technology Data Exchange (ETDEWEB)

Martin, Bradley E. (Air Force Research Laboratory, Eglin, FL); Kabir, Md. E. (Purdue University, West Lafayette, IN); Song, Bo; Chen, Wayne (Purdue University, West Lafayette, IN)

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 trends 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.

Suncor Energy annual report 2003

International Nuclear Information System (INIS)

2004-01-01

Suncor Energy Inc. is an integrated Canadian energy company with three operating segments: (1) oil sands production of light sweet and light sour crude oil, diesel fuel and other custom blends from oil sands mined in the Athabasca region of northeastern Alberta, (2) natural gas exploration, acquisition development, production, transportation and marketing of natural gas and crude oil in Canada and the United States, and (3) Sunoco, the marketing of petroleum and petrochemical products, mostly in Ontario and Quebec. This annual report includes the customary consolidated financial statements including the accounts of Suncor Energy Inc. and its subsidiaries and the company's proportionate share of the assets, liabilities, revenues, expenses and cash flows of joint ventures. The report states that the steady increase of Suncor's share price over the last decade reflects the company's growing oil production and expanding earnings and cash flow. It also reflects investor confidence in Suncor's ability to generate high returns. tabs., figs

Studies of environmental radioactivity in Cumbria. Pt. 8. Plutonium and americium in the intertidal sands of North-West England

Energy Technology Data Exchange (ETDEWEB)

Eakins, J.D.; Morgan, A.; Baston, G.M.N.; Pratley, F.A.; Yarnold, L.P.; Burton, P.J.

1988-03-01

Sand cores and surface sand samples have been collected from the sea-facing intertidal regions of West Cumbria, between Silloth and Walney Island. Sand cores were also taken from the Duddon estuary and Morecambe Bay. The samples were collected between June 1983 and March 1984 and have been analysed for /sup 238/Pu, /sup 239+240/Pu and /sup 241/Am. The integrated deposits of /sup 239+240/Pu and /sup 241/Am in intertidal sand between Silloth and Walney Island were about 4.2 and 7 TBq respectively. Combined, this represents about 1% of the total alpha-emitting actinide activity discharged from Sellafield to sea up to 1982; the corresponding value for the Duddon Estuary is about 0.3%. The actinide levels observed are compared to those of natural alpha emitters in intertidal sand. Only on beaches close to Sellafield did levels of discharged alpha emitters exceed those of natural alpha-emitting nuclides. In the vicinity of Sellafield, the annual dose to man from the inhalation of resuspended intertidal material is certainly less than 50 ..mu..Sv (committed effective dose equivalent) and may be substantially lower.

Composition of phenols in the primary tar of bituminous brown coal of the Ukrainian S. S. R

Energy Technology Data Exchange (ETDEWEB)

Karavaev, N M; Fadeicheva, A G; Kuznetsov, V I

1957-01-01

The phenol content in the low-temperature carbonizatin tar of brown coal is higher than in high-temperature coking tar, and the tar obtained in the carbonization of briquets in the Pintsch ovens was investigated after its separation at the carbonization plant. The phenol-containing fraction was extracted with 13 percent NaOH. The phenols were fractionated into narrow fractions at 8- to 9-millimeter pressure, and the fractions were identified by their melting point, n, OH content, analysis, and the melting point of their arylglycolic acids. Lower phenols (44 percent) wre found in the crude-phenol fraction, including 6 percent of crystalline PhOH, melting point 34/sup 0/; o-C/sub 6/H/sub 4/(Me)OH, melting point 27/sup 0/; 9.25 percent m- and o-cresols, with 32 percent m-cresol in the mixture EtC/sub 6/H/sub 4/OH formed 4.5 percent of the crude phenols, and consisted of o-, m-, and p-ethylphenols, 1,4,2-, 1,3,4-, 1,3,5-, and 1,2,4-xylenols.

Syncrude annual report 1994

International Nuclear Information System (INIS)

1994-01-01

Syncrude Canada Ltd. is the world's largest producer of custom made crude oil from the oil sands, and the largest single source of oil in Canada. This annual report claimed many outstanding achievements for 1994. A new production record resulted in higher revenue, lower unit operating costs, increased cash flow, improved productivity, and higher net income. With a focus on technology development and continuous improvement in operations, including environment, health and safety performance, operating results are projected to improve further. The formation of the Canadian Oil Sands Network for Research and Development (CONRAD) early in 1994 was a major step assuring maximum leverage from every dollar expended to realize this objective. Production of Syncrude Sweet Blend is expected to rise by over 10 million barrels to 81 million barrels a year at an average cash operating expenditure of Can$12.00/ barrel by the year 2000. The Corporation's business plans include capital investments for major projects, such as the North Mine hydrotransport, product quality enhancements, and upgrading facilities expansion. 4 tabs., 1 fig

Gasification of Rice Husk in a Downdraft Gasifier: The Effect of Equivalence Ratio on the Gasification Performance, Properties, and Utilization Analysis of Byproducts of Char and Tar

Directory of Open Access Journals (Sweden)

Zhongqing Ma

2015-03-01

Full Text Available Rice husks (RH are a potential biomass source for bio-energy production in China, such as bio-gas production by gasification technology. In this paper, a bench-scale downdraft fixed bed gasifier (DFBG and a tar sampling system were designed. The effect of equivalence ratio (ER on gasification performance in terms of the temperature in the gasifier, the composition distribution of the producer gas, and the tar content in the producer gas was studied. The maximum lower heating value of 4.44 MJ/Nm3, minimum tar content of 1.34 g/Nm3, and maximum cold gas efficiency of 50.85% were obtained at ER of 0.211. In addition, the characteristics of gasification byproducts, namely bio-char and bio-tar, were analyzed. The proximate and ultimate analysis (especially of the alkali metal, the surface morphology, the surface area, and the pore size distribution of the rice husk char (RHC were obtained by the use of X-ray fluorescence (XRF and scanning electron microscopy (SEM, as well as by using the Brunauer-Emmett-Teller (BET method. The components of light tar and heavy tar were obtained by using gas chromatography-mass spectrometry (GC-MS.

On Pluvial Compaction of Sand

DEFF Research Database (Denmark)

Jacobsen, Moust

At the Institute of Civil Engineering in Aalborg model tests on dry sand specimens have been carried out during the last five years. To reduce deviations in test results, the sand laying technique has been carefully studied, and the sand mass spreader constructed. Preliminary results have been...

MORPHOMETRIC CHARACTERIZATION OF THE SAND FRACTION IN A SAND GRAIN IMAGE CAPTURE SYSTEM1

Directory of Open Access Journals (Sweden)

Lucimar Arruda Viana

Full Text Available ABSTRACT Morphology studies assume significant importance in analysis of phenomena of granular systems packaging, in particular with a view to the use of the technique of soil stabilization named particle size correction in forest roads. In this context, this study aimed to develop and operationalize a Sand Grain Image Capture System and, hereby, determine the morphological indices of the sand fractions of two sandy soils called João Pinheiro (JP and Cachoeira da Prata (CP. Soil samples, air-dried, were sieved (2.0 mm nominal mesh size for removal of gravels. The materials that passed through the sieve were subjected to dispersion, washing in 0.053 mm nominal mesh size sieve, removal of organic matter and iron oxides to obtain the clean sand fractions. Subsequently, each soil sample was sieved for separation into twelve classes, between the diameters of 0.149 mm and 1.190 mm, using a Rotap shaker. Next, tests were carried out to characterize the morphometric attributes of the twelve classes of sand fractions of the soils studied. For validation of the performance of the Sand Grain Image Capture System, the results were compared to those obtained using a standard procedure for image analysis. The analysis of the results led to the following conclusions: (i the sand fraction of the JP soil presented higher values for the morphometric indices roundness, elongation and compactness compared to sand fraction of the CP soil; and (ii the Sand Grain Image Capture System worked properly, with practicality.

Proceedings of the Canadian Institute's 4. annual oil sands supply and infrastructure conference : maximizing opportunity and mitigating risks in a rapidly growing market

International Nuclear Information System (INIS)

2006-01-01

This conference addressed the challenges facing oil sands development, with particular reference to supply and infrastructure issues. Updates on oil sands markets and opportunities were presented along with strategies for mitigating risks in a rapidly growing market. The best practices for supplying a demanding market through supply shortages and high prices were identified along with policies that should be implemented to help overcome labour shortages. Some presentations expressed how commodities pricing and trends can impact business. Others showed how markets in China and the United States are prepared for oilsands products. The views of other international companies on oil sands was also discussed along with proposed plans to eliminate the infrastructure congestion and risks caused by expanding oil sands development. The challenges and benefits of investing in Alberta's oil sands were reviewed along with strategies to enhance upgrading and refining capacity in the province. Economic drivers and the creation of new markets were examined, and various export opportunities were reviewed along with industry management challenges concerning human resources, labour supply, training and education. The conference featured 10 presentations, of which 3 have been catalogued separately for inclusion in this database. refs., tabs., figs

Catalytic Pyrolysis of Tar Model Compound with Various Bio-Char Catalysts to Recycle Char from Biomass Pyrolysis

Directory of Open Access Journals (Sweden)

Jinmiao Liu

2016-03-01

Full Text Available Tar and char can be regarded as unwanted byproducts during the gasification process. In this study, three types of catalyst, i.e., biomass char (bio-char, nickel supported on biomass (Ni+bio-char, and nickel supported on bio-char (bio-char+Ni, were studied to compare the catalytic effects of different preparation methods on tar model compound removal. The structural characteristics of the three catalysts were also investigated by X-ray diffraction (XRD, scanning electron microscopy (SEM, and Brunauer-Emmett-Teller (BET methods. The results revealed that Ni+bio-char catalyst showed much higher activity for the reformation of toluene (C7H8 as a tar model compound than the other two catalysts. Toluene could be completely converted to small gas molecules at a conversion rate of 99.92% at 800 °C, and the maximum yield of gas was 432 mL/(mL C7H8. In particular, the H2 and CH4 yields were 339 and 85 mL/(mL C7H8 at 850 °C, respectively. An N2 absorption-desorption experiment demonstrated that the specific surface area of Ni+bio-char was 32.87 times that of bio-char and 8.39 times that of bio-char+Ni. Moreover, metallic nickel (Ni0 particles could be generated in the carbon matrix of Ni+bio-char catalyst. SEM analysis confirmed that the Ni+bio-char catalyst had a more porous structure. Nickel supported on biomass might be a promising catalyst for tar reformation because of its excellent catalytic activities.

Epoxy-borax-coal tar composition for a radiation protective, burn resistant drum liner and centrifugal casting method

International Nuclear Information System (INIS)

Boyer, N.W.; Taylor, R.S.

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

Bituminous sands : tax issues

International Nuclear Information System (INIS)

Patel, B.

2004-01-01

This paper examined some of the tax issues associated with the production of bitumen or synthetic crude oil from oil sands. The oil sands deposits in Alberta are gaining more attention as the supplies of conventional oil in Canada decline. The oil sands reserves located in the Athabasca, Cold Lake and Peace River areas contain about 2.5 trillion barrels of highly viscous hydrocarbons called bitumen, of which nearly 315 billion barrels are recoverable with current technology. The extraction method varies for each geographic area, and even within zones and reservoirs. The two most common extraction methods are surface mining and in-situ extraction such as cyclic steam stimulation (CSS); low pressure steam flood; pressure cycle steam drive; steam assisted gravity drainage (SAGD); hot water flooding; and, fire flood. This paper also discussed the following general tax issues: bituminous sands definition; bituminous sands leases and Canadian development expense versus Canadian oil and gas property expense (COGPE); Canadian exploration expense (CEE) for surface mining versus in-situ methods; additional capital cost allowance; and, scientific research and experimental development (SR and ED). 15 refs

Síndrome de TAR y estado de heterocigosis para anemia falciforme

Directory of Open Access Journals (Sweden)

Pilar Garavito

2004-01-01

Full Text Available Presentación de un paciente con el cuadro clínico del síndrome de TAR, quien presenta además un estado de heterocigosis para anemia falciforme. El síndrome de TAR, descrito por primera vez en 1959 por Shaw y Oliver, es un trastorno genético no común que ocurre con una prevalencia aproximada de 1: 500.000 a 1: 1.000.000 de nacidos vivos. En 1969 Hall y col. delinearon los criterios diagnósticos de este síndrome que incluyen ausencia bilateral del radio con presencia de ambos pulgares y trombocitopenia. Otras anomalías descritas en menor frecuencia son: Alteraciones óseas del húmero y cúbito, en los casos severos, focomelia, malformaciones de expresión variable en extremidades inferiores, malformaciones cardiacas e intolerancia a la leche de vaca (1, 2. Los hallazgos encontrados en este caso se comparan con los de la literatura y se discute su posible etiología, además de resaltar la importancia de realizar un diagnóstico y tratamiento precoz y preciso especialmente de la trombocitopenia

Morphological description and DNA barcoding study of sand rice (Agriophyllum squarrosum, Chenopodiaceae) collected in Kazakhstan.

Science.gov (United States)

Genievskaya, Yuliya; Abugalieva, Saule; Zhubanysheva, Aibatsha; Turuspekov, Yerlan

2017-11-14

Sand rice (Agriophyllum squarrosum (L.) Moq.) is an annual shrub-like plant adapted to the mobile sand dunes in desert and semi-desert regions of Asia. It has a balanced nutrient composition with relatively high concentration of lipids and proteins, which results in its nutrition being similar to legumes. Sand rice's proteins contain the full range of essential amino acids. However, calories content is more similar to wheat. These features together with desert stress resistance make sand rice a potential food crop resilient to ongoing climate change. It is also an important fodder crop (on young stages of growth) for cattle in arid regions of Kazakhstan. In our work, sand rice samples were collected from two distant regions of Kazakhstan as a part of the nation-wide project to determine genetic variation of the native flora. Samples were collected in western and southeastern parts of Kazakhstan separated by distances of up to 1300 km. Sequences of the nuclear ribosomal DNA ITS1-5.8S-ITS2 region and the chloroplast matK gene confirmed the identity of species defined by morphological traits. Comparison with GenBank sequences revealed polymorphic sequence positions among Kazakh populations and GenBank references, and suggested a distinction among local populations of sand rice. The phylogenetic analysis of nucleotide sequences showed a clear partition of A. squarrosum (L.) Moq. from Agriophyllum minus Fisch. & C.A. Mey, which grows in the same sand dunes environment. DNA barcoding analyses of ITS and matK sequences showed a segregation of A. squarrosum from A. minus into separate clades in Maximum-Likelhood dendrograms. ITS analysis can be successfully used to characterize A. squarrosum populations growing quite distant from each other. The data obtained in this work provide the basis for further investigations on A. squarrosum population structure and may play a role in the screening of sand rice plants growing in desert and semi-desert environments of Central Asia

Seasonal Dynamics of Phlebotomine Sand Fly Species Proven Vectors of Mediterranean Leishmaniasis Caused by Leishmania infantum.

Directory of Open Access Journals (Sweden)

Bulent Alten

2016-02-01

Full Text Available The recent geographical expansion of phlebotomine vectors of Leishmania infantum in the Mediterranean subregion has been attributed to ongoing climate changes. At these latitudes, the activity of sand flies is typically seasonal; because seasonal phenomena are also sensitive to general variations in climate, current phenological data sets can provide a baseline for continuing investigations on sand fly population dynamics that may impact on future scenarios of leishmaniasis transmission. With this aim, in 2011-2013 a consortium of partners from eight Mediterranean countries carried out entomological investigations in sites where L. infantum transmission was recently reported.A common protocol for sand fly collection included monthly captures by CDC light traps, complemented by sticky traps in most of the sites. Collections were replicated for more than one season in order to reduce the effects of local weather events. In each site, the trapping effort was left unchanged throughout the survey to legitimate inter-seasonal comparisons. Data from 99,000 collected specimens were analyzed, resulting in the description of seasonal dynamics of 56,000 sand flies belonging to L. infantum vector species throughout a wide geographical area, namely P. perniciosus (Portugal, Spain and Italy, P. ariasi (France, P. neglectus (Greece, P. tobbi (Cyprus and Turkey, P. balcanicus and P. kandelakii (Georgia. Time of sand fly appearance/disappearance in collections differed between sites, and seasonal densities showed variations in each site. Significant correlations were found between latitude/mean annual temperature of sites and i the first month of sand fly appearance, that ranged from early April to the first half of June; ii the type of density trend, varying from a single peak in July/August to multiple peaks increasing in magnitude from May through September. A 3-modal trend, recorded for P. tobbi in Cyprus, represents a novel finding for a L. infantum vector

Seasonal Dynamics of Phlebotomine Sand Fly Species Proven Vectors of Mediterranean Leishmaniasis Caused by Leishmania infantum.

Science.gov (United States)

Alten, Bulent; Maia, Carla; Afonso, Maria Odete; Campino, Lenea; Jiménez, Maribel; González, Estela; Molina, Ricardo; Bañuls, Anne Laure; Prudhomme, Jorian; Vergnes, Baptiste; Toty, Celine; Cassan, Cécile; Rahola, Nil; Thierry, Magali; Sereno, Denis; Bongiorno, Gioia; Bianchi, Riccardo; Khoury, Cristina; Tsirigotakis, Nikolaos; Dokianakis, Emmanouil; Antoniou, Maria; Christodoulou, Vasiliki; Mazeris, Apostolos; Karakus, Mehmet; Ozbel, Yusuf; Arserim, Suha K; Erisoz Kasap, Ozge; Gunay, Filiz; Oguz, Gizem; Kaynas, Sinan; Tsertsvadze, Nikoloz; Tskhvaradze, Lamzira; Giorgobiani, Ekaterina; Gramiccia, Marina; Volf, Petr; Gradoni, Luigi

2016-02-01

The recent geographical expansion of phlebotomine vectors of Leishmania infantum in the Mediterranean subregion has been attributed to ongoing climate changes. At these latitudes, the activity of sand flies is typically seasonal; because seasonal phenomena are also sensitive to general variations in climate, current phenological data sets can provide a baseline for continuing investigations on sand fly population dynamics that may impact on future scenarios of leishmaniasis transmission. With this aim, in 2011-2013 a consortium of partners from eight Mediterranean countries carried out entomological investigations in sites where L. infantum transmission was recently reported. A common protocol for sand fly collection included monthly captures by CDC light traps, complemented by sticky traps in most of the sites. Collections were replicated for more than one season in order to reduce the effects of local weather events. In each site, the trapping effort was left unchanged throughout the survey to legitimate inter-seasonal comparisons. Data from 99,000 collected specimens were analyzed, resulting in the description of seasonal dynamics of 56,000 sand flies belonging to L. infantum vector species throughout a wide geographical area, namely P. perniciosus (Portugal, Spain and Italy), P. ariasi (France), P. neglectus (Greece), P. tobbi (Cyprus and Turkey), P. balcanicus and P. kandelakii (Georgia). Time of sand fly appearance/disappearance in collections differed between sites, and seasonal densities showed variations in each site. Significant correlations were found between latitude/mean annual temperature of sites and i) the first month of sand fly appearance, that ranged from early April to the first half of June; ii) the type of density trend, varying from a single peak in July/August to multiple peaks increasing in magnitude from May through September. A 3-modal trend, recorded for P. tobbi in Cyprus, represents a novel finding for a L. infantum vector. Adults

Singing Sand Dunes

Indian Academy of Sciences (India)

ble low-frequency (s. 75–105 Hz), that can some- times be heard up to 10 km away. Scientific in- vestigations suggest that the sustained low fre- quency sound of sand dunes that resembles a pure note from a musical instrument, is due to the synchronized motion of well-sorted dry sand grains when they spontaneously ...

Physical properties and component contents of brown coal tars obtained in semicoking with a solid heat transfer semicoke

Energy Technology Data Exchange (ETDEWEB)

Kuznetsov, V I; Bobrova, A A

1955-01-01

Tar obtained in low-temperature carbonization of brown coals with brown-coal semicoke as a heat-transfer medium contains more water and dust, has a lower drop point, and a higher specific gravity, and contains more asphaltene and less paraffin than does tar from the same coal produced in rotating retorts or in shaft kilns. The brown-coal semicoke used as a heat-transfer medium produces partial thermal cracking of the fuel and polymerization of the products of secondary decompositions. The yield of asphaltenes is lowered when the carbonization temperature is raised.

Structural determinants of HIV-1 nucleocapsid protein for cTAR DNA binding and destabilization, and correlation with inhibition of self-primed DNA synthesis.

Science.gov (United States)

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.

Co-carcinogenesis: Human Papillomaviruses, Coal Tar Derivatives, and Squamous Cell Cervical Cancer

Directory of Open Access Journals (Sweden)

Harry W. Haverkos

2017-11-01

Full Text Available Cervical cancer (CC is the fourth most common cancers among women worldwide. Human papillomaviruses (HPVs play a major role in the etiology of CC, with several lines of epidemiologic and experimental evidence supporting a role for non-viral (co-carcinogens and host genetic factors in controlling the risk for progression to neoplasia among HPV-infected individuals. The role of co-carcinogens in the development of CC is significant in the developing world where poor sanitation and other socio-economic conditions increase the infectious cancer burden. Here, we discuss how exposure to environmental factors such as coal tar derivatives from cigarette smoking, tar-based sanitary products, and inhaled smoke from biomass-burning stoves, could activate host pathways involved in development of HPV-associated squamous cell cancers in resource-limited settings. Understanding interactions between these pathways with certain oncogenic HPV genotypes may guide implementation of strategies for control and treatment of HPV-associated cancers that develop in populations at high risk of exposure to various co-carcinogens.

The migration and monitoring of viscous NAPLs (coal tar and creosote) in the subsurface

Energy Technology Data Exchange (ETDEWEB)

Jackson, R. [Intera Engineering Ltd., Heidelberg, ON (Canada)

2009-07-01

The high viscosity of nonaqueous phase liquids (NAPLs) such as creosote and coal tar complicates efforts to monitor their mobility at contaminated sites. Viscous NAPLs can remain mobile for many decades after their application as a wood preservative, or after the closure of the facilities in which they were generated. NAPL-wet pathways in the subsurface can also lead to errors in residual saturation measurements. This abstract discussed issues related to creeping flow and the low seepage rates that are not accounted for using traditional measuring methods. Examples of creeping flow and the monitoring techniques used to assess it were presented for sites in British Columbia and Florida. The drainage of viscous NAPLs during water table declines was also considered, and a case study of a coal tar-removal procedures using polymer surfactant flooding was presented.

Forensic assessment of polycyclic aromatic hydrocarbons at the former Sydney Tar Ponds and surrounding environment using fingerprint techniques

International Nuclear Information System (INIS)

MacAskill, N. Devin; Walker, Tony R.; Oakes, Ken; Walsh, Margaret

2016-01-01

Polycyclic aromatic hydrocarbons (PAHs) were assessed spatially and temporally within and adjacent to a former coking and steel manufacturing facility in Sydney, Nova Scotia, Canada. Concentrations of PAHs were measured in surface soils, marine and estuary sediments prior to and during remediation of the Sydney Tar Ponds (STPs) site which was contaminated by nearly a century of coking and steel production. Previous studies identified PAHs in surficial marine sediments within Sydney Harbour, which were considered to be derived from STP discharges. Numerous PAH fingerprint techniques (diagnostic ratios, principal component analysis, quantitative and qualitative analysis) were applied to soil and sediment samples from the STPs and surrounding area to identify common source apportionment of PAHs. Results indicate coal combustion (from historical residential, commercial and industrial uses) and coal handling (from historic on-site stockpiling and current coal transfer and shipment facilities) are likely the principal source of PAHs found in urban soils and marine sediments, consistent with current and historical activities near these sites. However, PAH fingerprints associated with STP sediments correlated poorly with those of urban soils and marine sediments, but were similar to coal tar, historically consistent with by-products produced by the former coking operations. This study suggests PAH contamination of Sydney Harbour sediments and urban soils is largely unrelated to historic coking operations or recent remediation of the STPs site, but rather a legacy of extensive use of coal for a variety of activities. - Highlights: • PAHs were measured in soils and sediments near a former coking and steel facility. • Previous studies identified tar residues as main source of PAHs in marine sediments. • PAH fingerprint techniques were used to identify common source apportionment. • Fingerprint techniques indicated common sources derived from coal, not tar residues

Microscopic charcoal and tar (CHAT particles in peat: a 6500-year record of palaeo-fires in southern Sweden

Directory of Open Access Journals (Sweden)

B.A. Malmgren

2012-01-01

Full Text Available Peat stratigraphies of eleven raised bogs in southern Sweden were investigated. Measurements included the occurrence of charcoal and various tar particles. Most of the particles found were microscopic, i.e. 5–100 µm in diameter. Two distinctly different groups of particles were distinguished: (A charred fragments of plant tissue and (B objects formed from tar, which were classified into five sub-groups on the basis of morphology. Both charcoal and tar are indicative of mire and forest fires. We suggest that it is possible to use the different groups of particles as fire regime indicators. Hence, the high frequency of charcoal and tar (CHAT in the lower parts of the stratigraphies, i.e. in the lower strongly decomposed fen and carr peats that were formed before ca. 4000 cal 14C BP, could be indicative of intense and frequent local fires. The decreasing abundance of CHAT and the lower relative share of Type A particles within the lower strongly decomposed Sphagnum peat ca. 4000–2500 cal 14C BP signify a transition from local to regional fires. With a few exceptions, the uppermost weakly decomposed ombrotrophic peats formed after ca. 2500 cal 14C BP, in which both charcoal and tar are rare, indicate a period of low fire frequency at both local and regional scales. There is no regional variation in the lower material, and it seems that wildfires were common phenomena throughout southern Sweden during the first few thousand years after peat formation began 6–8000 years ago. From a climatological point of view, the mass occurrence of CHAT in the lower parts of the profiles indicates a warm and dry Mid Holocene with frequent and widespread wildfires, and a moist and cool Late Holocene with more sporadic fires. Spectral analysis of the entire dataset shows significant periodicities of 610, 70, 30, 21, 17 and 14 years, the two most significant being 14 and 70 years.

Formulation of Pine Tar Antidandruff Shampoo Assessment and Comparison With Some Commercial Formulations

Directory of Open Access Journals (Sweden)

M. Gharavi

1990-07-01

Full Text Available In this study a pine tar shampoo as a new antidandruff formulation is presented. Assessment of antidandruff preparations has been hampered by the lack of standardized schedules, and reliable methods of evaluation.Some antidandruff agents such as : Zinc pyri-thione pine tar, selenium sulphide and (sulfure were used in shampoos. Samples were coded as numbers 1,2 formulated by us and 3,4 formulated commercially. The grading scheme based on 10 point scale, and corneocyte count was carried out on 50 selected volunte¬ers. Corneocyte count and fungal study proved that pine tor shampoo is effective against pityrosporum ovale. Draize lest was used for determination of the irritancy potential of the samples. Results showed that samples numbered 1,2 were relatively innocous in comparison with the others. I urthermore,s kin sensitination test on rabbit also confirmed the results obtained by Draize test. Consumer judgments proved that all formulations were acceptable.

Coal-tar-based sealcoated pavement: a major PAH source to urban stream sediments.

Science.gov (United States)

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.

Coal-tar-based pavement sealcoat, polycyclic aromatic Hydrocarbons (PAHs), and environmental health

Science.gov (United States)

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.

The influence of partial oxidation mechanisms on tar destruction in TwoStage biomass gasification

DEFF Research Database (Denmark)

Ahrenfeldt, Jesper; Egsgaard, Helge; Stelte, Wolfgang

2013-01-01

adsorption and determined by stable isotope dilution analysis. The results have shown that partial oxidation reduces and converts primary tars into low molecular weight, polycyclic aromatic hydrocarbons (PAHs), primarily naphthalene. At temperatures above 950°C practically all phenol is converted...

Inhibition of HIV Replication by Cyclic and Hairpin PNAs Targeting the HIV-1 TAR RNA Loop

Science.gov (United States)

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

Inhibition of HIV Replication by Cyclic and Hairpin PNAs Targeting the HIV-1 TAR RNA Loop

Directory of Open Access Journals (Sweden)

Gregory Upert

2012-01-01

Full Text Available 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.

A real-time view of the TAR:Tat:P-TEFb complex at HIV-1 transcription sites

Directory of Open Access Journals (Sweden)

Knezevich Anna

2007-05-01

Full Text Available Abstract HIV-1 transcription is tightly regulated: silent in long-term latency and highly active in acutely-infected cells. Transcription is activated by the viral protein Tat, which recruits the elongation factor P-TEFb by binding the TAR sequence present in nascent HIV-1 RNAs. In this study, we analyzed the dynamic of the TAR:Tat:P-TEFb complex in living cells, by performing FRAP experiments at HIV-1 transcription sites. Our results indicate that a large fraction of Tat present at these sites is recruited by Cyclin T1. We found that in the presence of Tat, Cdk9 remained bound to nascent HIV-1 RNAs for 71s. In contrast, when transcription was activated by PMA/ionomycin, in the absence of Tat, Cdk9 turned-over rapidly and resided on the HIV-1 promoter for only 11s. Thus, the mechanism of trans-activation determines the residency time of P-TEFb at the HIV-1 gene, possibly explaining why Tat is such a potent transcriptional activator. In addition, we observed that Tat occupied HIV-1 transcription sites for 55s, suggesting that the TAR:Tat:P-TEFb complex dissociates from the polymerase following transcription initiation, and undergoes subsequent cycles of association/dissociation.

Structural evolution of Eucalyptus tar pitch-based carbons during carbonization

International Nuclear Information System (INIS)

Prauchner, Marcos J.; Pasa, Vanya M.D.; Molhallem, Nelcy D.S.; Otani, Choyu; Otani, Satika; Pardini, Luiz C.

2005-01-01

Wood tar pitches are generated as by-products by the charcoal manufacturing industry. They have a macromolecular structure constituted mainly by phenolic, guaiacylic, and siringylic units common to lignin. Due to their characteristics, biopitches are been investigated as precursors of carbon materials such as carbon fibers, bioelectrodes and activated carbons. In the present work the structural evolution of Eucalyptus tar pitches under carbonization is investigated, which is important for the improvement of planning and control of pitch processing and end-product properties during carbon material production. The studies involve X-ray diffraction and infrared analyses, besides helium density, BET surface area and BJH pore volume measurements. The results showed that the conversion of pitch into carbon basically involves three steps: (1) Up to around 600 deg C the material has an highly disordered structure, being the release of aliphatic side chains and volatiles the main events taking place. (2) Between 600 deg C and 800 deg C, condensation of aromatic rings occurs to form bi-dimensional hexagonal networks so that micro- and mesoporosity are developed. The 800 deg C-coke is constituted by two phases: one highly disordered and another more crystalline. (3) Over 800 deg C, both phases are gradually ordered. As defects are gradually removed, surface area and porosity decrease, approaching zero for the 2100 deg C-coke

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

Science.gov (United States)

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

Aromatic oxygen compounds boiling from 180/sup 0/ to 225/sup 0/ from acid oils in low-temperature tar

Energy Technology Data Exchange (ETDEWEB)

Jaeger, A; Kattwinkel, G

1950-01-01

To determine the composition of the Krupp-Lurgi low-temperature coal tar and to develop methods for isolating the various compounds, a quantitative investigation was made of the dry tar acid mixture. The aromatic O compounds boiling up to 225/sup 0/ were secured by fractionation with one of the several columns that are described. Large volumes of tar were fractionated under vacuum in an apparatus with a 10-liter flask, electrically heated, and provided with a fractionating column (packed) with a jacket supplied by recirculated oil, externally heated. Large volumes were fractionated to give sufficient quantities of the O compounds. The method of fractional extraction, not described herein, made the separation of the acid oils by fractional distillation much easier. The aromatic O compounds present in greatest proportion are relatively easily isolated; those present in small quantities and more difficult to separate can be removed as a mixture, which can be hydrogenated directly to solvents. Phenols and cresols are formed in about equal fractions in low-temperature carbonization. Of the various xylenols, the sym-xylenol is present to the greatest extent. O compounds with longer side chains than C/sub 2/ were present only to a very slight extent. At the temperature of formation of these tars, side chains of three or more C atoms formed closed ring compounds (indan derivatives, etc.). Little change appears to occur up to 225/sup 0/ in the fractionation of these acid oils.

Field test on sand compaction pile method with copper slag sand; Dosuisai slag wo mochiita SCP koho no shiken seko

Energy Technology Data Exchange (ETDEWEB)

Minami, K.; Matsui, H.; Naruse, E.; Kitazume, M. [Port and Harbour Research Inst., Kanagawa (Japan)

1997-09-20

This paper describes the sand compaction pile (SCP) method using copper slag sand. The SCP method is a method by which sand compaction piles are constructed in the ground, and improvement can be obtained in a short period. This method has been widely used even in the port areas for enhancing the bearing power of soft clay ground and the lateral resistance of sheet pile. A great deal of sand is required as a material. The sand requires high permeability, proper size distribution with less fine particle fraction content, easy compaction property with enough strength, and easy discharging property from the casing of construction machines as required properties. Recently, it becomes hard to secure proper sand materials. The copper slag sand is obtained from refining process of copper as a by-product which is quenched in water flow and crushed in water. The copper slag sand has higher particle density than that of sand, excellent permeability, and similar size distribution to that of sand. From compaction drainage triaxial compression test and permeability test, it was found that the mechanical properties of copper slag sand did not change by the crushing of grains with keeping excellent permeability. Through the test construction, applicability of the copper slag sand to the SCP method could be confirmed as an alternate material of sand. 17 refs., 9 figs., 4 tabs.

The effects of topical corticosteroids and a coal tar preparation on dithranol-induced irritation in patients with psoriasis

Energy Technology Data Exchange (ETDEWEB)

Swinkels, O.Q.J.; Kucharekova, M.; Prins, M.; Gerritsen, M.J.P.; van der Valk, P.G.M.; van de Kerkhof, P.C.M. [University of Nijmegen, Nijmegen (Netherlands). Medical Center

2003-02-01

Dithranol has been a mainstay in the treatment of psoriasis for more than 80 years. Although a safe approach, the irritation of the clinically uninvolved perilesional skin remains a major limitation of this treatment. Corticosteroids and coal tar solution have an anti-inflammatory potential. The aim of the present study was to investigate the clinical and cell-biological effects of two topical corticosteroids and a coal tar preparation on dithranol-irritated skin. The expression of epidermal proliferation, differentiation and inflammation markers and the clinical irritation scores indicate that the application of a high potency corticosteroid is the best approach to minimise dithranol irritation.

Catalytic steam reforming of tar derived from steam gasification of sunflower stalk over ethylene glycol assisting prepared Ni/MCM-41

International Nuclear Information System (INIS)

Karnjanakom, Surachai; Guan, Guoqing; Asep, Bayu; Du, Xiao; Hao, Xiaogang; Samart, Chanatip; Abudula, Abuliti

2015-01-01

Highlights: • Ni/MCM-41 was prepared by EG-assisted co-impregnation method. • EG-assisted co-impregnation method resulted in Ni particles well dispersed on MCM-41. • Ni/MCM-41-EG catalyst had high catalytic activity for tar reforming. • The highest H 2 gas yield was obtained when using 20 wt.% Ni/MCM-41-EG. • The catalysts were reused up to 5 cycles without any serious deactivation. - Abstract: Ethylene glycol (EG) assisted impregnation of nickel catalyst on MCM-41 (Ni/MCM-41-EG) was performed and applied for steam reforming of tar derived from biomass. The catalyst was characterized by SEM–EDX, BET, XRD, and TPR. It is found that smaller nickel particles were well dispersed on MCM-41 and better catalytic activity was shown for the Ni/MCM-41-EG when compared with the catalyst of Ni/MCM-41 prepared by using the conventional impregnation method. H 2 yield increased approximately 8% when using 20 wt.% Ni/MCM-41-EG instead of 20 wt.% Ni/MCM-41 for the steam reforming of tar derived from sunflower stalk. The catalyst reusability was also tested up to five cycles, and no obvious activity reduction was observed. It indicates that EG assisted impregnation method is a good way to prepare metal loaded porous catalyst with high catalytic activity, high loading amount and long-term stability for the tar reforming

Tar in road system wastes - bibliographic study - quick characterization methods; Le goudron dans les dechets du reseau routier - etude bibliographique - methodes de caracterisation rapides

Energy Technology Data Exchange (ETDEWEB)

Brazillet, C.; Domas, J.; Pepin, G.

2001-12-15

In the framework of the european regulations on the wastes management, the road structure wastes present a particularly problem because of the tar content and of the toxic associated polycyclic aromatic hydrocarbons. In order to chose the elimination or the valorization of these roads wastes, it is necessary to measure the tar content. After a presentation of the study objectives, a bibliographic study of the context, the challenges, the hydrocarbons, the tar characterization and the today situation of the french road network, the author presents the methods of PAH detection with a special attention on the well known methods: the PAK marker, the TSE and the toluene spot. (A.L.B.)

Biogeochemical gradients above a coal tar DNAPL

Energy Technology Data Exchange (ETDEWEB)

Scherr, Kerstin E., E-mail: kerstin.brandstaetter-scherr@boku.ac.at [University of Natural Resources and Life Sciences Vienna (BOKU), Department IFA-Tulln, Institute for Environmental Biotechnology, Konrad Lorenz Strasse 20, 3430 Tulln (Austria); Backes, Diana [University of Natural Resources and Life Sciences Vienna (BOKU), Department IFA-Tulln, Institute for Environmental Biotechnology, Konrad Lorenz Strasse 20, 3430 Tulln (Austria); Scarlett, Alan G. [University of Plymouth, Petroleum and Environmental Geochemistry Group, Biogeochemistry Research Centre, Drake Circus, Plymouth, Devon PL4 8AA (United Kingdom); Lantschbauer, Wolfgang [Government of Upper Austria, Directorate for Environment and Water Management, Division for Environmental Protection, Kärntner Strasse 10-12, 4021 Linz (Austria); Nahold, Manfred [GUT Gruppe Umwelt und Technik GmbH, Ingenieurbüro für Technischen Umweltschutz, Plesching 15, 4040 Linz (Austria)

2016-09-01

Naturally occurring distribution and attenuation processes can keep hydrocarbon emissions from dense non aqueous phase liquids (DNAPL) into the adjacent groundwater at a minimum. In a historically coal tar DNAPL-impacted site, the de facto absence of a plume sparked investigations regarding the character of natural attenuation and DNAPL resolubilization processes at the site. Steep vertical gradients of polycyclic aromatic hydrocarbons, microbial community composition, secondary water quality and redox-parameters were found to occur between the DNAPL-proximal and shallow waters. While methanogenic and mixed-electron acceptor conditions prevailed close to the DNAPL, aerobic conditions and very low dissolved contaminant concentrations were identified in three meters vertical distance from the phase. Comprehensive two-dimensional gas chromatography–mass spectrometry (GC × GC–MS) proved to be an efficient tool to characterize the behavior of the present complex contaminant mixture. Medium to low bioavailability of ferric iron and manganese oxides of aquifer samples was detected via incubation with Shewanella alga and evidence for iron and manganese reduction was collected. In contrast, 16S rDNA phylogenetic analysis revealed the absence of common iron reducing bacteria. Aerobic hydrocarbon degraders were abundant in shallow horizons, while nitrate reducers were dominating in deeper aquifer regions, in addition to a low relative abundance of methanogenic archaea. Partial Least Squares – Canonical Correspondence Analysis (PLS-CCA) suggested that nitrate and oxygen concentrations had the greatest impact on aquifer community structure in on- and offsite wells, which had a similarly high biodiversity (H’ and Chao1). Overall, slow hydrocarbon dissolution from the DNAPL appears to dominate natural attenuation processes. This site may serve as a model for developing legal and technical strategies for the treatment of DNAPL-impacted sites where contaminant plumes are

Galveston Island, Texas, Sand Management Strategies

Science.gov (United States)

2016-07-01

billion m3 of beach quality sand . However, Texas projects to date have not utilized these sources because of transportation costs. The lack of nearby...estimate that the San Luis Pass flood shoal contains approximately 11.8 million yd3 of beach quality sand . However, it is expected that if permits...a source of beach- quality sand . 2. Sand could be intercepted before it reaches the present dry beach. ERDC/CHL TR-16-13 55 3. The volume of

Is annual recharge coefficient a valid concept in arid and semi-arid regions?

Directory of Open Access Journals (Sweden)

Y. Cheng

2017-10-01

Full Text Available Deep soil recharge (DSR (at depth greater than 200 cm is an important part of water circulation in arid and semi-arid regions. Quantitative monitoring of DSR is of great importance to assess water resources and to study water balance in arid and semi-arid regions. This study used a typical bare land on the eastern margin of Mu Us Sandy Land in the Ordos Basin of China as an example to illustrate a new lysimeter method of measuring DSR to examine if the annual recharge coefficient is valid or not in the study site, where the annual recharge efficient is the ratio of annual DSR over annual total precipitation. Positioning monitoring was done on precipitation and DSR measurements underneath mobile sand dunes from 2013 to 2015 in the study area. Results showed that use of an annual recharge coefficient for estimating DSR in bare sand land in arid and semi-arid regions is questionable and could lead to considerable errors. It appeared that DSR in those regions was influenced by precipitation pattern and was closely correlated with spontaneous strong precipitation events (with precipitation greater than 10 mm other than the total precipitation. This study showed that as much as 42 % of precipitation in a single strong precipitation event can be transformed into DSR. During the observation period, the maximum annual DSR could make up 24.33 % of the annual precipitation. This study provided a reliable method of estimating DSR in sandy areas of arid and semi-arid regions, which is valuable for managing groundwater resources and ecological restoration in those regions. It also provided strong evidence that the annual recharge coefficient was invalid for calculating DSR in arid and semi-arid regions. This study shows that DSR is closely related to the strong precipitation events, rather than to the average annual precipitation, as well as the precipitation patterns.

Oil Sands Regional Aquatics Monitoring Program (RAMP) 5 year report

International Nuclear Information System (INIS)

Fawcett, K.

2003-05-01

This 5 year report outlined and examined the activities of the Regional Aquatics Monitoring Program (RAMP) from its introduction in 1997 up to 2001. The RAMP is a multi-stakeholder program comprised of industry and government representatives as well as members of aboriginal groups and environmental organizations. The objectives of RAMP are to monitor aquatic environments in the oil sands region in order to allow for assessment of regional trends and cumulative effects, as well as to provide baseline data against which impact predictions of recent environmental impact assessments can be verified. Scientific programs conducted as part of RAMP during the 5-year period included water quality and sediment quality analyses; fish monitoring; benthic communities monitoring; water quality and aquatic vegetation analyses of wetlands; and hydrology and climate monitoring. RAMP's programs have expanded annually in scope as a result of increased oil sands development in the region. This report provided outlines of RAMP's individual program objectives and organizational structures, as well as details of all studies conducted for each year. Data were collected for all major study areas were presented, and program methodologies for assessing and identifying trends were outlined. refs., tabs., figs

Fifth DOE symposium on enhanced oil and gas recovery and improved drilling technology. Volume 2. Oil

Energy Technology Data Exchange (ETDEWEB)

Linville, B. [ed.

1979-01-01

Volume 2 contains papers from the following sessions: residual oil determination; thermal methods; heavy oil-tar sands; technology transfer; and carbon dioxide flooding. Individual papers were processed.

Numerical simulation of aeolian sand ripples

International Nuclear Information System (INIS)

Kang Liqiang; Guo Liejin

2004-01-01

With a new horizontal saltation displacement vector, a model is implemented to simulate the initiation and evolution of aeolian sand ripples. In the model, saltation distance considers the effects of surface height and slope. A linear stability analysis is also carried out for formation of sand ripples. The results show that, the model can be able to successfully reproduce sand ripples which can increase in scale by merging of small ripples. The linear stability analysis indicates that sand ripples appear when the relaxation rate parameter is below a threshold value and wind strength parameter is larger than a critical value. The results also verified that the formation of sand ripples is a self-organization process

Preparation, Characterization, and Activation of Co-Mo/Y Zeolite Catalyst for Coal Tar Conversion to Liquid Fuel

Directory of Open Access Journals (Sweden)

Didi Dwi Anggoro

2017-05-01

Full Text Available One of many efforts to convert coal tar into alternative liquid fuel is by hydrocracking. This research aims to determine the impregnation of Co-Mo/Y zeolite, its characteristics, the effect of impregnation temperature and time, and also the best Co-Mo/Y zeolite impregnation condition for the conversion of coal tar. This research was conducted in several steps, impregnating Co from Co(NO32.6H2O and Mo from (NH46Mo7O24.4H2O into Zeolite Y in liquid media, drying at 100 °C for 24 hours, and calcination at 550 °C for 3 hours. Coal tar was then reacted with hydrogen gas (as a reactant, and Co-Mo/Zeolite Y (as a catalyst was conducted at 350 °C. Characteristic analysis showed that Co and Mo had impregnated into the Y zeolite, as well as it made no change of catalyst’s structure and increased the total acidity. The higher of impregnation temperature was increased the catalyst crystallinity, total acidity, and yield of gasoline. The longer impregnation time was reduced crystallinity value, but total acidity and yield were increased. GC analysis showed that products included into the gasoline product (C8, C9, and C10. Copyright © 2017 BCREC Group. All rights reserved Received: 13rd November 2016; Revised: 12nd February 2017; Accepted: 16th February 2017 How to Cite: Anggoro, D.D., Buchori, L., Silaen, G.C., Utami, R.N. (2017. Preparation, Characterization, and Activation of Co-Mo/Y Zeolite Catalyst for Coal Tar Conversion to Liquid Fuel. Bulletin of Chemical Reaction Engineering & Catalysis, 12 (2: 219-226 (doi:10.9767/bcrec.12.2.768.219-226 Permalink/DOI: http://dx.doi.org/10.9767/bcrec.12.2.768.219-226

Japan's involvement in oil sands development

International Nuclear Information System (INIS)

Sugiura, T.

1994-01-01

According to Japanese national policy, exploration and development by Japanese companies in overseas countries are promoted in order to ensure stable oil supplies. Japan Canada Oil Sands Limited (JACOS), part of the JAPEX group, was established during the 1978 world oil crisis to explore and develop Canadian oil sand resources in accordance with Japan's national policy. The JAPEX group, including JACOS, has invested $123 million in oil sands projects in Alberta. JAPEX's first involvement in oil sands was in the Primrose Project operated by Norcen in the Cold Lake area. Five years of cyclic steam stimulation pilot tests did not produce sufficiently good results to justify further operation. The second involvement was the PCEJ Project, a joint effort by four companies that are participating in a bitumen recovery test project in the Athabasca Deposit. JACOS holds 2,452 km 2 of oil sands leases in Alberta. Tests conducted since 1978 in the PCEJ Project include multiwell steam injection pilot tests, some of which showed promise. JACOS is also participating in steam assisted gravity drainage projects and in federal/provincial research programs. Obstacles identified in developing Alberta oil sands are the lack of a bitumen pipeline to Edmonton and the insufficient length of oil sands leases (currently 10 years), given the difficulties of oil sand development. 10 figs

MouldingSandDB – a modern database storing moulding sands properties research results

Directory of Open Access Journals (Sweden)

J. Jakubski

2011-01-01

Full Text Available The complexity of foundry processes requires the use of modern, advanced IT tools for optimization, storage and analysis of t echnicaldata. Properties of moulding and core sands that are collected in research laboratories, manufacturers, and finally in the foundries, are not in use later on. It seems important to create a database that will allow to use the results stored, along with the possibility of searching according to set criteria, adjusted to casting practice. This paper presents part of the database named „MouldingSandDB”, which allows to collect and search data for synthetic moulding sands.

Policy Analysis of the Canadian Oil Sands Experience

Energy Technology Data Exchange (ETDEWEB)

None, None

2013-09-01

For those who support U.S. oil sands development, the Canadian oil sands industry is often identified as a model the U.S. might emulate, yielding financial and energy security benefits. For opponents of domestic oil sands development, the Canadian oil sands experience illustrates the risks that opponents of development believe should deter domestic policymakers from incenting U.S. oil sands development. This report does not seek to evaluate the particular underpinnings of either side of this policy argument, but rather attempts to delve into the question of whether the Canadian experience has relevance as a foundational model for U.S. oil sands development. More specifically, this report seeks to assess whether and how the Canadian oil sands experience might be predictive or instructive in the context of fashioning a framework for a U.S. oil sands industry. In evaluating the implications of these underpinnings for a prospective U.S. oil sands industry, this report concentrates on prospective development of the oil sands deposits found in Utah.

How confident is Fort McKay that industry can reclaim oil sand development

Energy Technology Data Exchange (ETDEWEB)

Fitzpatrick, C. [Fort McKay First Nations, AB (Canada)

2004-02-05

This presentation described how traditional environmental knowledge (TEK) can provide valuable information for both the reclamation design and assessment of oil sand development in Fort McKay. Conservation is valued by the Fort McKay First Nations communities who claim that current reclamation methods are too slow, and that the land is not being brought back to its original use with the uniqueness of the boreal landscape. Elders have noted that each year the water level in the Athabasca River is lower. The blowing tailings and coke dust are causing trees to dye and driving animals away. There is concern that the animals that remain may not be safe to eat. The Fort McKay First Nation community has stated that it will view reclamation as a success only when it functions with proof over many generations. The major concerns include: salt in the water draining from reclaimed areas; salt in the soils of reclaimed area; muskeg cannot be recreated; and, the issue of whether cranberry, blueberry and streambank forest areas can be recreated, along with traditional medicinal plants. Other concerns include the loss of rivers such as the Beaver Creek and Tar River, and that the water in reclaimed areas may not be suitable for animals to live in or to drink. tabs., figs.

How confident is Fort McKay that industry can reclaim oil sand development

International Nuclear Information System (INIS)

Fitzpatrick, C.

2004-01-01

This presentation described how traditional environmental knowledge (TEK) can provide valuable information for both the reclamation design and assessment of oil sand development in Fort McKay. Conservation is valued by the Fort McKay First Nations communities who claim that current reclamation methods are too slow, and that the land is not being brought back to its original use with the uniqueness of the boreal landscape. Elders have noted that each year the water level in the Athabasca River is lower. The blowing tailings and coke dust are causing trees to dye and driving animals away. There is concern that the animals that remain may not be safe to eat. The Fort McKay First Nation community has stated that it will view reclamation as a success only when it functions with proof over many generations. The major concerns include: salt in the water draining from reclaimed areas; salt in the soils of reclaimed area; muskeg cannot be recreated; and, the issue of whether cranberry, blueberry and streambank forest areas can be recreated, along with traditional medicinal plants. Other concerns include the loss of rivers such as the Beaver Creek and Tar River, and that the water in reclaimed areas may not be suitable for animals to live in or to drink. tabs., figs

A study of global sand seas

Science.gov (United States)

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

You're standing on it! Coal-tar-based pavement sealcoat and environmental and human health

Science.gov (United States)

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

2013-01-01

Coal-tar-based sealcoat—a product marketed to protect and beautify asphalt pavement—is a potent source of polycyclic aromatic hydrocarbons (PAHs) to air, soils, streams and lakes, and homes. Does its use present a risk to human health?

Do increases in cigarette prices lead to increases in sales of cigarettes with high tar and nicotine yields?

Science.gov (United States)

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.

Numerical simulation of wind-sand movement in the reversed flow region of a sand dune with a bridge built downstream.

Science.gov (United States)

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.

The Holocene evolution of the beach and inland aeolian sand of the north-central Mediterranean coast of Israel

Science.gov (United States)

Roskin, Joel; Sivan, Dorit; Bookman, Revital; Shteinberg, Gilad

2015-04-01

distance and age and did not significantly differ from the values of beach sand. The spatial distribution and temporal clustering of the 1.2-1.1 ka ages does not seem stochastic. However, this age range does not coincide with any local or regional climate change or anthropogenic anomaly that could explain the enhanced sand mobility. Assuming no late Holocene change in coastal sand supply and availability, sand transport may have been due to short term climate (multi-annual) episodes of increased windiness that may have followed short-term or cumulative removal of stabilizing dune vegetation by man, a hypothesis that requires further investigation.

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.

Science.gov (United States)

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.

Sand dune tracking from satellite laser altimetry

Science.gov (United States)

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

Thermodynamic studies of a series of homologous HIV-1 TAR RNA ligands reveal that loose binders are stronger Tat competitors than tight ones.

Science.gov (United States)

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.

Composition and Dissolution of a Migratory, Weathered Coal Tar Creosote DNAPL

Directory of Open Access Journals (Sweden)

Kerstin E. Scherr

2016-09-01

Full Text Available Opaque, viscous tars derived from the carbonization of fossile carbon feedstocks, such coal tars and creosote, are long-term sources of groundwater contamination, predominantly with poly- and heterocyclic aromatic hydrocarbons (PAH. The dissolution, ageing and migratory behavior of dense, non aqueous phase liquid (DNAPL coal tar blobs and pools forming at the aquitard is not sufficiently understood to estimate the risk and adequately design groundwater treatment measures at a contaminated site. In this study, we investigate the composition and dissolution of a migrated, aged creosote DNAPL and corresponding experimental and groundwater profiles using comprehensive two-dimensional gas chromatography (GCxGC-MS. GC-FID unresolved compounds were attributed to methylated homocyclic species using GCxGC-MS in the Methylanthracene weight range. Equilibrium concentrations were estimated using Raoult’s law, assuming non-ideal behavior. Low molecular weight compounds were found to be prevalent even after decades of weathering, with Naphthalene (8% by mass representing the most abundant identified compound, contrary to the expected preferential depletion of hydrophilic compounds. Morevoer, dimethylnaphthalenes were relatively more abundant in the aqueous boundary layer than in the DNAPL. DNAPL migration over 400m with the groundwater flow effected lower viscosity and specific gravity of the migrated phase body in a superposition of weathering, transport and aquifer chromatography effects. Based on a decomposition of analysed and estimated constituents using the group contribution approach, reference DNAPL values for activity coefficients γi were used to model aqueous solubilities for selected compounds. Anthracene was close to its theoretical precipitation limit in the bulk DNAPL. While laboratory and modelled DNAPL dissolution behavior agree well, field data imply the presence of specific interfacial in situ processes significantly impacting dissolution

Sequential Subterranean Transport of Excavated Sand and Foraged Seeds in Nests of the Harvester Ant, Pogonomyrmex badius.

Directory of Open Access Journals (Sweden)

Walter R Tschinkel

Full Text Available During their approximately annual nest relocations, Florida harvester ants (Pogonomyrmex badius excavate large and architecturally-distinct subterranean nests. Aspects of this process were studied by planting a harvester ant colony in the field in a soil column composed of layers of 12 different colors of sand. Quantifying the colors of excavated sand dumped on the surface by the ants revealed the progress of nest deepening to 2 m and enlargement to 8 L in volume. Most of the excavation was completed within about 2 weeks, but the nest was doubled in volume after a winter lull. After 7 months, we excavated the nest and mapped its structure, revealing colored sand deposited in non-host colored layers, especially in the upper 30 to 40 cm of the nest. In all, about 2.5% of the excavated sediment was deposited below ground, a fact of importance to sediment dating by optically-stimulated luminescence (OSL. Upward transport of excavated sand is carried out in stages, probably by different groups of ants, through deposition, re-transport, incorporation into the nest walls and floors and remobilization from these. This results in considerable mixing of sand from different depths, as indicated in the multiple sand colors even within single sand pellets brought to the surface. Just as sand is transported upward by stages, incoming seeds are transported downward to seed chambers. Foragers collect seeds and deposit them only in the topmost nest chambers from which a separate group of workers rapidly transports them downward in increments detectable as a "wave" of seeds that eventually ends in the seed chambers, 20 to 80 cm below the surface. The upward and downward transport is an example of task-partitioning in a series-parallel organization of work carried out by a highly redundant work force in which each worker usually completes only part of a multi-step process.

AmTAR2: Functional characterization of a honeybee tyramine receptor stimulating adenylyl cyclase activity.

Science.gov (United States)

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.

General toxic effects of shale tars on the human body

Energy Technology Data Exchange (ETDEWEB)

Kahn, H; Sillam, A

1972-01-01

Of 115 workers in close contact with oil shale tars, 80 percent complained of headache, fatigue, and stomach aches. Vegetative dystonia, asthenovegetative, or asthenic syndromes were diagnosed in 32 percent of the cases. An excessive excretion of free phenols was found in the urine of 13 percent of the patients and an excess of sulfates and coproporphyrin in 27 and 29 percent, respectively. The statistical analysis of clinical data indicates a relation to biochemical changes. The immunological reactivity studies showed that in 60 percent of the cases the immunological resistance decreased markedly.

Determination of Natural Radioactivity in the North East Beach Sands of Madagascar

International Nuclear Information System (INIS)

Randriamora, T.H.; Razafindramiandra, H.A.; Raoelina Andraimbololona; Ravelomanantsoa, S.D.; Ralaivelo, M.A.L.; Rasolonirina, M.; Zafimanjato, J. L. R.; Randriantseheno, H.F.

2017-01-01

Exploration and exploitation of radioactive ores (ilmenite, zircon and monazite) are considered as the main source of exposure to ionizing radiation of the population living in the coast of Analanjorofo Region (Fenerive-Est Districts, Rural municipality Ampasimbe Manantsatrana). Radioactivity measurements have been performed in this region. The distribution of natural radionuclide gamma-emitters ( 238 U, 232 Th and 40 K) and their respective annual effective dose rates have been determined for sand(s), water and air. The samples have been collected along and around the coast of the region. The radiation emitted from the natural radionuclide containing in the environmental samples has been determined by gamma spectrometry system and Radon meter (SARAD). Exposure dose rates at 1 m above the ground have been measured along the coast and in the villages around the exploitation sites. Dose rate measurements have been performed by Dosimeter Graetz X5DE, equipped of Geiger Muller Counter. Results have been compared with the reference values provided by IAEA (BSS 115) and UNSCEAR 2000.

Distribution of natural radionuclides in soils and beach sands of Abana-Çatalzeytin (Kastamonu)

Energy Technology Data Exchange (ETDEWEB)

Kurnaz, Aslı, E-mail: akurnaz@kastamonu.edu.tr; Özcan, Murat, E-mail: murat-ozcan@kastamonu.edu.tr; Çetiner, M. Atıf, E-mail: macetiner@kastamonu.edu.tr [Kastamonu University, Arts and Sciences Faculty, Department of Physics, Kastamonu (Turkey)

2016-03-25

A gamma spectrometric study of distribution of natural radionuclides in soil and beach sand samples collected from the terrestrial and coastal environment of Abana and Çatalzeytin counties of Kastamonu Province in Turkey was performed with the aim of estimating the radiation hazard of the tourist area and the concentrations of {sup 238}U, {sup 232}Th and {sup 40}K were determined. The activity concentrations of {sup 238}U, {sup 232}Th and {sup 40}K were determined in the ranges 14.95–56.0, 46.5–99.4 and 357.5–871.3 Bqkg{sup −1} for soil samples and the mean concentrations were ascertained as 42.34, 71.24 and 624.18 Bqkg{sup −1}, respectively. In sand samples, {sup 238}U, {sup 232}Th and {sup 40}K contents were varied in the ranges of 13.35-41.6, 30.9-53.4 and 275.5-601.3 Bqkg{sup −1} and the mean concentrations were ascertained as 20.57, 45.05 and 411.71 Bqkg{sup −1}, respectively. The mean annual effective doses were calculated as 113.08 and 69.16 µSvy{sup −1} for the soil and sand samples, respectively.

The effects of higher cigarette prices on tar and nicotine consumption in a cohort of adult smokers.

Science.gov (United States)

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.

Protection Performance Simulation of Coal Tar-Coated Pipes Buried in a Domestic Nuclear Power Plant Using Cathodic Protection and FEM Method

Energy Technology Data Exchange (ETDEWEB)

Chang, H. Y.; Lim, B. T.; Kim, K. S.; Kim, J. W.; Park, H. B. [KEPCO Engineering and Construction Company, Gimcheon (Korea, Republic of); Kim, Y. S.; Kim, K. T. [Andong National University, Andong (Korea, Republic of)

2017-06-15

Coal tar-coated pipes buried in a domestic nuclear power plant have operated under the cathodic protection. This work conducted the simulation of the coating performance of these pipes using a FEM method. The pipes, being ductile cast iron have been suffered under considerably high cathodic protection condition beyond the appropriate condition. However, cathodic potential measured at the site revealed non-protected status. Converting from 3D CAD data of the power plant to appropriate type for a FEM simulation was conducted and cathodic potential under the applied voltage and current was calculated using primary and secondary current distribution and physical conditions. FEM simulation for coal tar-coated pipe without defects revealed over-protection condition if the pipes were well-coated. However, the simulation for coal tar-coated pipes with many defects predict that the coated pipes may be severely degraded. Therefore, for high risk pipes, direct examination and repair or renewal of pipes are strongly recommended.

bentonite-sand mixture as new backfill/buffer material

International Nuclear Information System (INIS)

Cui Suli; Liu Jisheng; Zhang Huyuan; Liang Jian

2008-01-01

The mixture of bentonite and quartz sand is suggested as a new backfill/buffer material for geological disposal of HLW. To improve the further design of underground laboratory and in-situ industrial construction test, the optimization of sand addition to bentonite is focused at present research stage. Based on summarizing the research results abroad, laboratory tests were conducted on the mixture of GMZ001 bentonite and quartz sand, such as compaction test and swelling tests etc. Test data shows that GMZ bentonite-sand mixture exhibits a favorite compaction with a 30% sand addition, a highest swelling pressure with a 20% sand addition, and a decreasing plasticity with increases in sand addition and pore liquid concentration. (authors)

Comparison between predicted and observed sand waves and sand banks in the North Sea

NARCIS (Netherlands)

Hulscher, Suzanne J.M.H.; van den Brink, G.M.

2001-01-01

For the first time a prediction model of regular morphological patterns on the seabed was tested against observations of sand wave and sand bank occurrence in the entire North Sea. The model, which originates from first physical principles, predicts this occurrence via two dimensionless parameters

Corrosão de parafusos fixados à madeira tratada com soluções de creosoto vegetal Corrosion of screws fixed into wood treated with wood tar creosote solutions

Directory of Open Access Journals (Sweden)

Juarez Benigno Paes

2002-05-01

Full Text Available O objetivo desta pesquisa foi avaliar a corrosão de parafusos auto-rosqueáveis fixados à madeira tratada com soluções preservativas preparadas com creosoto vegetal, em condições de campo. Obteve-se o creosoto vegetal bruto por meio da destilação à temperatura de 110 - 255ºC do alcatrão vegetal. Uma fração dos destilados foi lavada com solução a 9% de bicarbonato de sódio, obtendo-se o creosoto vegetal purificado. Ambas as frações foram enriquecidas com 3% de naftenato de cobre; 3% de naftenato de zinco; 3% naftenato de cobalto; 2% de TBTO; 2% de tribromofenato de tubutil-estanho; 2% de pentaclorofenol; ou 0,4% de trióxido de arsênico. Foram preparadas 16 soluções, sendo 14 enriquecidas, além do creosoto vegetal bruto e do creosoto vegetal purificado. Estacas confeccionadas com madeira de alburno de Eucalyptus grandis foram tratadas pelo processo de célula- cheia (processo Bethell. Após o tratamento, parafusos auto-rosquéaveis de ferro zincado foram fixados às estacas. O ensaio foi instalado em três localidades da Zona da Mata de Minas Gerais (Viçosa, Ponte Nova e Leopoldina. A corrosividade das soluções de creosoto vegetal foi comparada à causada pelo creosoto mineral. As soluções preparadas com creosoto vegetal purificado foram menos corrosivas que suas similares preparadas com creosoto vegetal bruto, assemelhando-se ao creosoto mineral.The objective of this research was to evaluate the corrosion of screws fixed into wood treated with preservative solutions of wood tar creosote. The crude wood tar creosote was obtained through distillation of wood tar at 110 - 255ºC. A fraction of this product was washed with a solution of sodium bicarbonate at 9%, resulting in purified wood tar creosote. Both fractions were enriched with 3% of copper naphtenate, 3% of zinc naphtenate, 3% of cobalt naphtenate, 2% of TBTO, 2% of tributhyl-tin tribromophenate, 2% of pentachlorophenol, or with 0.4% of arsenic trioxide. A total

Critical State of Sand Matrix Soils

Science.gov (United States)

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

Production and global transport of Titan's sand particles

Science.gov (United States)

Barnes, Jason W.; Lorenz, Ralph D.; Radebaugh, Jani; Hayes, Alexander G.; Arnold, Karl; Chandler, Clayton

2015-06-01

Previous authors have suggested that Titan's individual sand particles form by either sintering or by lithification and erosion. We suggest two new mechanisms for the production of Titan's organic sand particles that would occur within bodies of liquid: flocculation and evaporitic precipitation. Such production mechanisms would suggest discrete sand sources in dry lakebeds. We search for such sources, but find no convincing candidates with the present Cassini Visual and Infrared Mapping Spectrometer coverage. As a result we propose that Titan's equatorial dunes may represent a single, global sand sea with west-to-east transport providing sources and sinks for sand in each interconnected basin. The sand might then be transported around Xanadu by fast-moving Barchan dune chains and/or fluvial transport in transient riverbeds. A river at the Xanadu/Shangri-La border could explain the sharp edge of the sand sea there, much like the Kuiseb River stops the Namib Sand Sea in southwest Africa on Earth. Future missions could use the composition of Titan's sands to constrain the global hydrocarbon cycle.

Production of gas and volatile materials by distillation of tars, etc

Energy Technology Data Exchange (ETDEWEB)

Arson, M

1860-04-25

The principle of this production is in the treating of heavy oils with heat, their transformation occurring nearly completely by the action of this agent. The apparatus used consists of a retort of such a form that it has openings at the two ends immediately opposed to each other. One serves to introduce the oil and the other to remove the tar and gas produced. At the exit of the apparatus the gas passes into coolers like those used for coal gas.

High temperature thermal energy storage in moving sand

Science.gov (United States)

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.

Sand to Root Transfer of PAHs and PCBs by Carrots Grown on Sand with Pure Substances and Biosolids Amended Sand

OpenAIRE

Sablayrolles, Caroline; Montréjaud-Vignoles, Mireille; Silvestre, Jérôme; Patria, Lucie

2006-01-01

A study on behaviour of trace organic compounds (Polycyclic Aromatic Hydrocarbons, PAH, and Polychlorinated Biphenyls, PCB) in a sand-plant system has been carried out, with the reclamation of wastewater treatment plant biosolids for agriculture in mind. Carrot plants (Daucus carota) were grown on soilless culture (sand), to provide optimal transfer conditions, in plant containers inside a temperature regulated greenhouse. There were two types of experiment. The trace organic compounds have i...

Synthesis Of 2- (1- Naphthyl) Ethanoic Acid ( Plant Growth Regulator ) From Coal Tar And Its Application

International Nuclear Information System (INIS)

Khin Mooh Theint; Tin Myint Htwe

2011-12-01

Plant growth regulators, which are commonly called as plant hormones, naturally produced non-nutrient chemical compounds involved in growth and development. Among the various kinds of plant growth regulators, 2- (1- Naphthyl ) ethanoic acid especially encourages the root development of the plant. In this work, NAA was successfuly synthesized from naphthalene which was extracted from coal tar. The purity of naphthalene, -Chloromethyl naphthalene, -Naphthyl acetonitrile, - Naphthyl acetic acid or 2 - ( 1-Naphthyl ) ethanoic acid were also confirmed by Thin Layer Chromatography, and by spectroscopy methods. The yield percent of NAA based on naphthalene was found to be 2.1%. The yield percent of naphthaleneFrom coal tar is found to be 4.09%. The effect of NAA on root development was also studied in different concentrations of soy bean (Glycine max)and cow pea (Vigna catjang walp).

Smokers' sensory beliefs mediate the relation between smoking a light/low tar cigarette and perceptions of harm.

Science.gov (United States)

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 (pmarketing 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/

Inhibition of both HIV-1 reverse transcription and gene expression by a cyclic peptide that binds the Tat-transactivating response element (TAR RNA.

Directory of Open Access Journals (Sweden)

Matthew S Lalonde

2011-05-01

Full Text Available The RNA response element TAR plays a critical role in HIV replication by providing a binding site for the recruitment of the viral transactivator protein Tat. Using a structure-guided approach, we have developed a series of conformationally-constrained cyclic peptides that act as structural mimics of the Tat RNA binding region and block Tat-TAR interactions at nanomolar concentrations in vitro. Here we show that these compounds block Tat-dependent transcription in cell-free systems and in cell-based reporter assays. The compounds are also cell permeable, have low toxicity, and inhibit replication of diverse HIV-1 strains, including both CXCR4-tropic and CCR5-tropic primary HIV-1 isolates of the divergent subtypes A, B, C, D and CRF01_AE. In human peripheral blood mononuclear cells, the cyclic peptidomimetic L50 exhibited an IC(50 ∼250 nM. Surprisingly, inhibition of LTR-driven HIV-1 transcription could not account for the full antiviral activity. Timed drug-addition experiments revealed that L-50 has a bi-phasic inhibition curve with the first phase occurring after HIV-1 entry into the host cell and during the initiation of HIV-1 reverse transcription. The second phase coincides with inhibition of HIV-1 transcription. Reconstituted reverse transcription assays confirm that HIV-1 (- strand strong stop DNA synthesis is blocked by L50-TAR RNA interactions in-vitro. These findings are consistent with genetic evidence that TAR plays critical roles both during reverse transcription and during HIV gene expression. Our results suggest that antiviral drugs targeting TAR RNA might be highly effective due to a dual inhibitory mechanism.

Radiation hazards evaluation for selected sand samples from Camburi beach, Vitoria, Espirito Santo, Brazil

International Nuclear Information System (INIS)

Barros, Livia F.; Pecequilo, Brigitte R.S.

2013-01-01

In this work, a single location at Camburi beach, known to be a naturally high background region, was studied. Radiation hazards indexes and annual effective dose were evaluated from the 226 Ra, 232 Th and 40 K sands activities concentrations. Sand samples were monthly collected during 2011, dried, sealed in standard 100 mL HPDE polyethylene flasks and measured by high resolution gamma spectrometry after a 4 weeks in-growth period. The 226 Ra concentration was determined from the weighted average concentrations of 214 Pb and 214 Bi. The 232 Th concentration was determined from the weighted average concentrations of 228 Ac, 212 Pb and 212 Bi and the 4 0K from its single gamma transition. The results, considering samples gamma-rays self-attenuation, show activities concentrations in the range from 6 Bq kg -1 to 39 Bq kg -1 for 226 Ra, 13 Bq kg -1 to 161 Bq kg -1 for 232 Th, and 7 Bq kg -1 to 65 Bq kg -1 for 40 K. The radium equivalent activity for the studied samples ranged from 26 Bq kg -1 to 274 Bq kg - '1. The external and internal hazard indexes varied, respectively, from 0.07 to 0.74 and from 0.09 to 0.85. The annual effective dose values laid from 0.07 mSv.y -1 to 0.72 mSv.y - '1. All values obtained in this work are below the radiological protection recommended limits. (author)

Exposure to Phlebotomus argentipes (Diptera, Psychodidae, Phlebotominae sand flies in rural areas of Bihar, India: the role of housing conditions.

Directory of Open Access Journals (Sweden)

Paritosh Malaviya

Full Text Available Visceral Leishmaniasis (VL is a vector-borne infectious disease, caused by the protozoan Leishmania donovani, which is transmitted by phlebotomine sand flies. In an earlier study in Bihar, India, we found an association between incidence of VL and housing conditions. In the current study we investigated the influence of housing structure and conditions in and around the house on the indoor abundance of Phlebotomus argentipes, the vector of VL in this area.In each of 50 study villages in Muzaffarpur district, we randomly selected 10 houses. Light traps were installed in each house for one night during three annual peaks of sand fly density over two successive years. Sand flies captured were morphologically identified and segregated by species, sex and feeding status. Data on housing conditions and socio-economic status were also collected. We fitted a linear mixed-effects regression model with log-transformed P. argentipes counts as outcome variable and village as random effect.P. argentipes was found in all but four of the 500 households. There was considerable variability between the years and the seasons. On bivariate analysis, housing structure, dampness of the floor, keeping animals inside, presence of animal dung around the house, and socio-economic status were all significantly associated with sand fly density. Highest sand fly densities were observed in thatched houses. In the multivariate model only the housing structure and socio-economic status remained significant.Better housing conditions are associated with lower sand fly densities, independent of other socio-economic conditions. However, in this area in Bihar even in the better-built houses sand flies are present.

The pentane- and toluene-soluble fractions of a petroleum residue and three coal tars by size exclusion chromatography and UV-fluorescence spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Karaca, F.; Millan-Agorio, M.; Morgan, T.J.; Bull, I.D.; Herod, A.A.; Kandiyoti, R. [University of London Imperial College Science Technology & Medicine, London (United Kingdom). Dept. of Chemical Engineering

2008-01-15

A petroleum atmospheric pressure distillate residue and three tars derived from different coals using different severities of thermal treatment were separated into seven fractions using column chromatography on silica and sequential elution by the solvent sequence pentane, toluene, acetonitrile, pyridine, 1-methyl-2-pyrrolidinone (NMP) and water. The fractions from the four extractions have been compared using size exclusion chromatography (SEC) in NMP as eluent and by synchronous ultra-violet-fluorescence (UV-F). This paper concerns the pentane and toluene soluble fractions only since these are the least polar fractions. By SEC, the size of the aromatic molecules increased from the first pentane soluble fractions to the toluene-soluble fractions, with the petroleum residue fractions of larger size than the equivalent fractions from coal liquids. The three coal tars showed significant differences, indicating that temperature of pyrolysis had a significant effect on the molecular size. Synchronous UV-F spectra of the four sets of fractions, in solution in NMP, again showed significant differences between the petroleum residue and the coal tars, as well as amongst the three coal tars. In general, the petroleum residue fractions contained smaller aromatic clusters than the coal liquid fractions. These low-polarity fractions contained material excluded from the column porosity in SEC that was unlikely to consist of aggregates of polar molecules.

Analysis of wind-blown sand movement over transverse dunes.

Science.gov (United States)

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.

Investigating Efficient Tar Management from Biomass and Waste to Energy Gasification Processes

Science.gov (United States)

2015-04-01

internal combustion engine (ICE) can mean spark ignition or diesel ( compression ignition ). It is likely that the light tars could be made to burn in...filled with methyl chloroform to allow rapid acquisition and analysis via an auto handler on the gas chromatography machine. An additional test...flare and venturi are lost. If the venturi were lost air can draw back into the process pipe creating an air fuel mixture that may ignite . PLASMA

Sand consolidation

Energy Technology Data Exchange (ETDEWEB)

Spain, H H

1965-01-21

In a sand consolidation method in which there is injected a mixture of resin-forming liquids comprising an aryl-hydroxy low molecular weight compound, a water- soluble aldehyde, and a catalyst, an improvement is claimed which comprises diluting the resin-forming liquids with a diluent and with water so that the yield of the resin is sufficient to consolidate the sand particles with the minimum desirable pressure. The diluent may be mutually soluble in water and in the resin-forming liquids, and does not affect the setting time of the polymer. The aldehyde and the aryl-hydroxy compound may be in ratio of 5:1, and the diluent, methyl alcohol, is present in a ratio of 2:1 with reference to the water.

Sands at Gusev Crater, Mars

Science.gov (United States)

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).

Direct Chlorination of Zircon Sand

International Nuclear Information System (INIS)

Dwiretnani Sudjoko; Budi Sulistyo; Pristi Hartati; Sunardjo

2002-01-01

It was investigated the direct chlorination of zircon sand in a unit chlorination equipment. The process was in semi batch. The product gas was scrubbed in aqueous NaOH. It was search the influence of time, ratio of reactant and size of particle sand to the concentration of Zr and Si in the product. From these research it was found that as the times, ratio of reactant increased, the concentration of Zr increased, but the concentration of Si decreased, while as grain size of zircon sand decreased the concentration of Zr decreased, but the concentration of Si increased. (author)

Continued studies of soil improvement and revegetation of tailings sand slopes. Environmental Research Monograph 1977-4

Energy Technology Data Exchange (ETDEWEB)

Rowell, M J

1977-01-01

Fertilizer studies continued on a 5-year old revegetated area on a tailings sand dike in the Athabasca Tar Sands area. In June 1976 levels of available N, P, K, and S were adequate for plant growth. However, even where fertilizers were added levels of mineral N had dropped to low levels by September. Plant top production early in the 1976 season was increased by application of nitrogen fertilizer during the previous August. Erosion of the area was negligible in 1976. In the new revegetation experiments on steep tailings and slopes, erosion could be minimized by the rapid establishment of a plant cover. Nutrient losses in surface water runoff amounted to a maximum of only 2.6 kg N, 0.4 kg P, 4.1 kg K and 3.4 kg S/ha in the treatments studied. Water infiltration into the dike was rapid and varied between 24.0 and 30.5 cm/h. Estimates suggested that between 13 and 34% of the intercepted rainfall leached below the 30 cm depth while plants were being established during the first year of growth. Estimates of nutrient losses below the root zone (30 cm) ranged between 1.3 and 31.2 kg N/ha; <0.1 kg P/ha; 1.1 and 10.1 kg K/ha and 4.8 to 38.1 kg S/ha in the different treatments studied. The seed mix used contained oats as a nurse crop and 9 grass and 4 legume species. Plant growth was adequate to protect the soil surface from serious erosion. The dry weight production by the oats was considerably greater than for either the grasses or legumes. The cover produced by grasses and legumes alone would have been adequate in terms of erosion control except in those treatments involving heavy applications of mine overburdens. The dry weight production of root and shoot tissues was about the same. Root growth was largely restricted to the surface 15 cm. Total numbers of bacteria, fungi and actinomycetes as well as total soil respiration was considerably greater in soils from the revegetation experiments in comparison to samples of fresh or weathered tailings sand.

Plasma Gasification of Wood and Production of Gas with Low Content of Tar

Czech Academy of Sciences Publication Activity Database

Hlína, Michal; Hrabovský, Milan; Kopecký, Vladimír; Konrád, Miloš; Kavka, Tetyana; Skoblja, S.

2006-01-01

Roč. 56, suppl. B (2006), s. 1179-1184 ISSN 0011-4626. [Symposium on Plasma Physics and Technology/22nd./. Praha, 26.6.2006-29.6.2006] R&D Projects: GA ČR GA202/05/0669 Institutional research plan: CEZ:AV0Z20430508 Keywords : tar * plasma * biomass gasification Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.568, year: 2006

PFB air gasification of biomass. Investigation of product formation and problematic issues related to ammonia, tar and alkali

Energy Technology Data Exchange (ETDEWEB)

Padban, Nader

2000-09-01

Fluidised bed thermal gasification of biomass is an effective route that results in 100 % conversion of the fuel. In contrast to chemical, enzymatic or anaerobic methods of biomass treatment, the thermal conversion leaves no contaminated residue after the process. The product gas evolved within thermal conversion can be used in several applications such as: fuel for gas turbines, combustion engines and fuel cells, and raw material for production of chemicals and synthetic liquid fuels. This thesis treats a part of the experimental data from two different gasifiers: a 90 kW{sub th} pressurised fluidised bubbling bed gasifier at Lund University and a 18 MW{sub th} circulating fluidised bed gasifier integrated with gas turbine (IGCC) in Vaernamo. A series of parallel and consecutive chemical reactions is involved in thermal gasification, giving origin to formation of a variety of products. These products can be classified within three major groups: gases, tars and oils, and char. The proportion of these categories of species in the final product is a matter of the gasifier design and the process parameters. The thesis addresses the technical and theoretical aspects of the biomass thermochemical conversion and presents a new approach in describing the gasification reactions. There is an evidence of fuel effect on the characteristics of the final products: a mixture of plastic waste (polyethylene) and biomass results in higher concentration of linear hydrocarbons in the gas than gasification of pure biomass. Mixing the biomass with textile waste (containing aromatic structure) results in a high degree of formation of aromatic compounds and light tars. Three topic questions within biomass gasification, namely: tar, NO{sub x} and alkali are discussed in the thesis. The experimental results show that gasification at high ER or high temperature decreases the total amount of the tars and simultaneously reduces the contents of the oxygenated and alkyl-substituted poly

Effects of aqueous effluents from in situ fossil fuel processing technologies on aquatic systems. Annual progress report, January 1-December 31, 1979

Energy Technology Data Exchange (ETDEWEB)

Bergman, H.L.

1980-01-04

This is the third annual progress report for a continuing EPA-DOE jointly funded project to evaluate the effects of aqueous effluents from in situ fossil-fuel processing technologies on aquatic biota. The project is organized into four project tasks: (1) literature review; (2) process water screening; (3) methods development; and (4) recommendations. Our Bibliography of aquatic ecosystem effects, analytical methods and treatment technologies for organic compounds in advanced fossil-fuel processing effluents was submitted to the EPA for publication. The bibliography contains 1314 citations indexed by chemicals, keywords, taxa and authors. We estimate that the second bibliography volume will contain approximately 1500 citations and be completed in February. We compiled results from several laboratories of inorganic characterizations of 19 process waters: 55 simulated in situ oil-shale retort waters; and Hanna-3, Hanna-4B 01W and Lawrence Livermore Hoe Creek underground coal gasification condenser waters. These process waters were then compared to a published summary of the analyses from 18 simulated in situ oil-shale retort waters. We completed this year 96-h flow-through toxicity bioassays with fathead minnows and rainbow trout and 48-h flow-through bioassays with Daphnia pulicaria exposed to 5 oil-shale process waters, 1 tar-sand process water, 2 underground coal gasification condenser waters, 1 post-gasification backflood condenser water, as well as 2 bioassays with fossil-fuel process water constituents. The LC/sub 50/ toxicity values for these respective species when exposed to these waters are given in detail. (LTN)

Thermal Conductivity of Polymer Composite poypropilene-Sand

International Nuclear Information System (INIS)

Betha; Mashuri; Sudirman; Karo Karo, Aloma

2001-01-01

Thermal conductivity composite materials polypropylene (PP)-sand have been investigated. PP composite with sand to increase thermal conductivity from the polymer. The composite in this observation is done by mixing matrix (PP melt flow 2/10)and filler sand)by means tool labo plastomil. The result of thermal conductivity is composite of PP-sand which is obtained increase and followed by the raising of filler particle volume fraction. The analysis of thermal conductivity based on the model Cheng and Vachon, model Lewis and Nielsen where this model has the function to support experiment finding. It is proved that Lewis' and Nielsen's model almost approach experiment result. And then thermal conductivity raising will be analyzed by the model of pararel-series conductive with the two (2)phases system. It is showed that sand in PP MF 2 composite have the big role to increase the thermal conductivity than sand in PP MF 10 composition, but it is not easy to shape conductive medium

Final report on Thermally Modified Sand demonstration project

Energy Technology Data Exchange (ETDEWEB)

1994-09-23

The use of salt and salt/sand mixtures on icy roadway surfaces has dramatically increased during the past 30 years. Despite extensive documentation on salt related damage to the roadway improvements, vehicles and the environment, road maintenance departments have continued to rely on this practice. Road maintenance departments in northern climate areas have long recognized the safety benefits for public mobility on icy roadways from the use of sand. As an abrasive material, the sand improves the surface traction that results in more drivable and less hazardous road conditions during the winter months. Stockpiles of pure sand stored during the winter months oftentimes freeze into large unworkable, monolithic piles. To maintain a free-flowing condition, it has been found to be necessary to add salt to the sand. The addition of salt in amounts ranging from 5 to 10 percent to that of sand, is usually sufficient to provide relatively free-flowing abrasive material that could be stored in stockpiles and applied to icy road surfaces with conventional sand spreading trucks. Another alternative for winter storage of pure sand to maintain a free-flowing condition is in humidity-controlled, heated buildings. As would be expected, this method has high capital and operating costs. and not cost effective for general highway maintenance use. The invention demonstrated herein is a method of thermally modifying pure sand that will remain in a free-flowing state throughout the winter season without the need for the salt additive. The thermally modified sand provides an abrasive material that when applied to icy roads does not cause environmental and corrosive damage as done by the application of sand with salt. By employing a very simple process of freezing screened sand particles by forced air convection under subfreezing conditions, the invention creates a product that has significant value in terms of economic and environmental benefits.

Evaluate of head loss, sediment value and copper removal in sand media (rapid sand filter

Directory of Open Access Journals (Sweden)

Daneshi Navab

2014-06-01

Full Text Available Along with the technology development and increasing consumption of water resources, we are experiencing low qualities in the mentioned resources. Copper brings about serious environment al pollution, threatening human health and ecosystem. This metal found variously in water resources and industrial activities. Therefore, it needs to treat the water resources from these excessive amounts. Different methods have used for this reason but the most used method during recent years has been the absorption by economic absorbers such as sand. Rapid sand filters usually used in water and wastewater treatment plants for water clarification. In this research, a single layer gravity rapid sand filter has used to reduce different concentrations of copper. sediment value and head loss arising in filter media is simulated by using combination of Carman-Kozeny, Rose and Gregory models in different discharges of rapid sand filter. Results have shown that with increasing in discharge and decreasing in input copper concentration, arriving time to given head loss, is increasing. In addition, results demonstrated that with increasing in copper concentration in influent, removal efficiency is decreasing somewhat. Results of this research can applied in an appropriate design of rapid sand filter to copper removal, a prediction of rapid sand filter ability to copper removal and an estimation of arising head loss during filter work thus evaluating of time interval backwash. DOI: http://dx.doi.org/10.3126/ije.v3i2.10641 International Journal of the Environment Vol.3(2 2014: 276-286

Study on sand particles creep model and open pit mine landslide mechanism caused by sand fatigue liquefaction

Science.gov (United States)

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.

40 CFR 60.591 - Definitions.

Science.gov (United States)

2010-07-01

....593(c). Petroleum means the crude oil removed from the earth and the oils derived from tar sands..., distillate fuel oils, residual fuel oils, lubricants, or other products through the distillation of petroleum...

Use of sand wave habitats by silver hake

Science.gov (United States)

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.